JP4048744B2 - Image forming apparatus and image forming method - Google Patents

Description

【０１０９】
【化２】

【０１１０】
〈離型剤の含有割合〉
本発明のトナーにおける離型剤の含有割合としては、通常１〜３０質量％とされ、好ましくは２〜２０質量％、更に好ましくは３〜１５質量％とされる。
〈結晶性ポリエステル〉
請求項１６〜請求項３０に係るトナー粒子は、結着樹脂中に結晶性ポリエステルを含有する樹脂粒子と、着色剤粒子とを塩析／融着させて得られる会合型の着色粒子（トナー粒子）からなる。
【０１１１】
ここに、樹脂粒子中に含有される結晶性ポリエステルは、当該樹脂粒子を融着させて得られるトナーに良好な定着性（画像形成支持体に対する接着性）を付与する化合物である。
〔結晶性ポリエステルの物性〕
かかる結晶性ポリエステルの融点は５０〜１３０℃であることが好ましく、更に好ましくは６０〜１２０℃とされる。
【０１１２】
５０〜１３０℃の範囲に融点を有する結晶性ポリエステルによれば、得られるトナーにおいて、その全体の溶融粘度を下げることが可能となり、紙等に対する接着性の向上を図ることができる。しかも、当該結晶性ポリエステルが存在しても、高温側の弾性率が好ましい範囲に維持されるため、良好な耐オフセット性が発揮される。結晶性ポリエステルの融点が５０℃未満の場合には、定着性自体は向上するものの、保存性が低下し実用性に問題を生じる。一方、融点が１３０℃を超える場合には、溶融開始温度が高くなるために、定着性の向上に対する寄与が低く、定着性改良の効果発揮が少なくなる。
【０１１３】
ここに、結晶性ポリエステルの融点とは、示差熱量分析装置（ＤＳＣ）にて測定された値をいう。具体的には、０℃から２００℃まで１０℃／ｍｉｎの条件で昇温（第一昇温過程）したときに測定される吸熱ピークの最大ピークを示す温度を融点とする。そして、この融点は、後述する「ＤＳＣによる第一昇温過程での吸熱ピーク（Ｐ１）」と一致する。
【０１１４】
融点の具体的な測定装置としては、パーキンエルマー社製のＤＳＣ−７等を挙げることができる。
【０１１５】
結晶性ポリエステルの数平均分子量は１，５００〜１５，０００であることが好ましく、更に好ましくは２，０００〜１０，０００とされる。
【０１１６】
１，５００〜１５，０００の範囲に数平均分子量を有する結晶性ポリエステルによれば、得られるトナーにおいて、その全体の溶融粘度低下を発揮させるための結着樹脂（無定形高分子）との溶融状態での相溶性が向上され、より低温側での定着性が向上する。この数平均分子量が１，５００未満の場合では、結晶性ポリエステルの溶融粘度が過度に低くなり、却って相溶状態が不均一になりやすく、定着性を向上することができにくくなる。一方、数平均分子量が１５，０００を超える場合には、結晶性ポリエステルの溶融に時間がかかり、この場合でも相溶状態が不均一になるために、定着性の向上効果が低くなってしまう。
【０１１７】
ここに、結晶性ポリエステルの数平均分子量とは、下記の条件に従って測定された分子量から求められる値をいう。
（条件）
・使用機種：「ＬＣ−６Ａ」（島津製作所社製）
・カラム ：「ウルトラスタイラジェルＰｌｕｓ」
・分析温度：６０℃
・溶媒 ：ｍ−クレゾール／クロロベンゼン＝３／１（体積比）
・検量線 ：標準ポリスチレン検量線
結晶性ポリエステルの溶融粘度（融点＋２０℃での溶融粘度）は１００ｄＰａ・ｓ以下であることが好ましく、更に好ましくは６０ｄＰａ・ｓ以下とされる。
【０１１８】
溶融粘度が１００ｄＰａ・ｓ以下である結晶性ポリエステルによれば、得られるトナーにおいて、結着樹脂を含めた全体の溶融粘度を下げることが可能になり、定着性が向上する。この溶融粘度が１００ｄＰａ・ｓを超える場合には、全体の溶融粘度が高くなるために、定着性の向上効果が低くなってしまう。
【０１１９】
ここに、結晶性ポリエステルの溶融粘度（融点＋２０℃での溶融粘度）とは、コーンプレート粘度計で測定された値をいう。
【０１２０】
結晶性ポリエステルのＧＰＣでのピーク分子量は６，０００〜５０，０００とされる。
【０１２１】
結晶性ポリエステルは、ＤＳＣによる第一昇温過程での吸熱ピーク（Ｐ１）が５０〜１３０℃、特に６０〜１２０℃に存在することが好ましい。
【０１２２】
また、結晶性ポリエステルは、ＤＳＣによる第一冷却過程での発熱ピーク（Ｐ２）が３０〜１１０℃、特に４０〜１２０℃に存在することが好ましい。
【０１２３】
ここに、吸熱ピーク（Ｐ１）と、発熱ピーク（Ｐ２）とは、Ｐ１≧Ｐ２の関係が成立する。温度差（Ｐ１−Ｐ２）は、特に制限されるものではないが、５０℃以下であることが好ましい。
【０１２４】
上記のような熱的特性を有する結晶性ポリエステルを含有させることにより、優れたオフセット防止効果（広い定着可能温度域）および優れた定着性（高い定着率）を発揮させることができる。
【０１２５】
本発明の効果を発揮させるためには、結着樹脂と結晶性ポリエステルとが互いに独立した状態で存在していることが好ましい。すなわち、結晶性ポリエステルはシャープに溶解し、その溶融した状態で結着樹脂を溶解する作用が働き、結果としてトナー全体の溶融粘度を下げることができ、定着性を向上することができるものである。また、互いに独立して存在することにより、高温側での弾性率の低下を抑えることが可能となるため、耐オフセット性も損なうことがない。
【０１２６】
吸熱ピーク（Ｐ１）が５０℃未満に存在する場合には、融解温度が低いために、定着性は向上するものの、耐オフセット性および保存安定性が低下する。
【０１２７】
また、吸熱ピーク（Ｐ１）が１３０℃を超える範囲に存在する場合には、融解温度が高いために、結着樹脂との溶解温度が高くなり、結果として定着性の向上を図ることができない。
【０１２８】
再結晶化の状態を示す発熱ピーク（Ｐ２）が３０℃未満に存在する場合には、かなり低い温度まで冷却しないと再結晶化することができず、そのような物質は、結晶性が低い状態でトナー中に存在することになり、定着性の向上に寄与することができない。
【０１２９】
また、発熱ピーク（Ｐ２）が１１０℃を超える範囲に存在する場合には、再結晶化する温度が高過ぎて、いわゆる溶融温度も高くなり、低温定着性が損なわれる。
【０１３０】
吸熱ピーク（Ｐ１）および発熱ピーク（Ｐ２）は、示差熱量分析装置（ＤＳＣ）により測定される。昇温・冷却条件としては、０℃にて１分間放置した後、１０℃／ｍｉｎの条件で２００℃まで昇温し、その際に測定される最大の吸熱ピークを示す温度をＰ１とする。その後、２００℃にて１分間放置後、１０℃／ｍｉｎの条件で降温し、その際に測定される最大の発熱ピークを示す温度をＰ２とする。具体的な測定装置としては、パーキンエルマー社製のＤＳＣ−７等を挙げることができる。
〔結晶性ポリエステルの構成〕
結晶性ポリエステルとしては、脂肪族ジオールと、脂肪族ジカルボン酸（酸無水物および酸塩化物を含む）とを反応させて得られるポリエステルが好ましい。
【０１３１】
結晶性ポリエステルを得るために使用されるジオールとしては、エチレングリコール、ジエチレングリコール、トリエチレングリコール、１，２−プロピレングリコール、１，３−プロピレングリコール、１，４−ブタンジオール、１，４−ブテンジオール、ネオペンチルグリコール、１，５−ペンタングリコール、１，６−ヘキサンジオール、１，４−シクロヘキサンジオール、１，４−シクロヘキサンジメタノール、ジプロピレングリコール、ポリエチレングリコール、ポリプロピレングリコール、ポリテトラメチレングリコール、ビスフェノールＡ、ビスフェノールＺ、水素添加ビスフェノールＡ等を挙げることができる。
【０１３２】
結晶性ポリエステルを得るために使用されるジカルボン酸としては、シュウ酸、マロン酸、コハク酸、グルタル酸、アジピン酸、ピメリン酸、スペリン酸、アゼライン酸、セバシン酸、マレイン酸、フマール酸、シトラコ酸、イタコン酸、グルタコ酸、ｎ−ドデシルコハク酸、ｎ−ドデセニルコハク酸、イソドデシルコハク酸、イソドデセニルコハク酸、ｎ−オクチルコハク酸、ｎ−オクテニルコハク酸、これらの酸無水物あるいは酸塩化物を挙げることができる。
【０１３３】
特に好ましい結晶性ポリエステルとしては、１，４−シクロヘキサンジメタノールとアジピン酸とを反応して得られるポリエステル、１，６−ヘキサンジオールとセバシン酸とを反応して得られるポリエステル、エチレングリコールとコハク酸とを反応して得られるポリエステル、エチレングリコールとセバシン酸とを反応して得られるポリエステル、１，４−ブタンジオールとコハク酸とを反応して得られるポリエステルを挙げることができ、これらのうち、１，４−シクロヘキサンジメタノールとアジピン酸とを反応して得られるポリエステルが最も好ましい。
〈結晶性ポリエステルの含有割合〉
本発明のトナーにおける結晶性ポリエステルの含有割合としては、通常１〜５０質量％とされ、好ましくは５〜４０質量％、更に好ましくは５〜３０質量％とされる。
〈離型剤を含有する樹脂粒子／結晶性ポリエステルを含有する樹脂粒子〉
本発明において「離型剤を含有する樹脂粒子」は、結着樹脂を得るための単量体中に離型剤を溶解させ、得られる単量体溶液を水系媒体中に分散させ、この系を重合処理することにより、ラテックス粒子として得ることができる。
【０１３４】
また、「結晶性ポリエステルを含有する樹脂粒子」は、結着樹脂を得るための単量体中に結晶性ポリエステルを溶解させ、得られる単量体溶液を水系媒体中に分散させ、この系を重合処理することにより、ラテックス粒子として得ることができる。
【０１３５】
かかる樹脂粒子の重量平均粒径は１０〜２０００ｎｍであることが好ましい。
離型剤及び／又は結晶性ポリエステルを結着樹脂中にを含有する樹脂粒子を得るための重合法としては、乳化重合法、懸濁重合法、シード重合法などの造粒重合法を挙げることができる。
【０１３６】
離型剤及び／又は結晶性ポリエステルを含有する樹脂粒子を得るための好ましい重合法としては、臨界ミセル濃度以下の濃度の界面活性剤を溶解してなる水系媒体中に、離型剤及び／又は結晶性ポリエステルを単量体中に溶解してなる単量体溶液を、機械的エネルギーを利用して油滴（１０〜１０００ｎｍ）を形成して分散液を調製し、得られた分散液に水溶性重合開始剤を添加して、ラジカル重合させる方法（以下、この明細書において「ミニエマルジョン法」という。）を挙げることができる。なお、水溶性重合開始剤を添加することに代えて、または、当該水溶性重合開始剤を添加するとともに、油溶性の重合開始剤を前記単量体溶液中に添加してもよい。
【０１３７】
ここに、機械的エネルギーによる油滴分散を行うための分散機としては、特に限定されるものではなく、高速回転するローターを備えた攪拌装置「クレアミックス（ＣＬＥＡＲＭＩＸ）」（エム・テクニック（株）製）、超音波分散機、機械式ホモジナイザー、マントンゴーリンおよび圧力式ホモジナイザーなどを挙げることができる。また、分散粒子径としては、１０〜１０００ｎｍとされ、好ましくは３０〜３００ｎｍとされる。
〈結着樹脂〉
本発明のトナーを構成する結着樹脂は、ＧＰＣにより測定される分子量分布で１５０，０００〜１，０００，０００の領域にピークまたはショルダーを有する高分子量成分と、１，０００〜２０，０００の領域にピークまたはショルダーを有する低分子量成分とを含有する樹脂であることが好ましい。さらに、５０，０００〜１４０，０００の領域にピークまたはショルダーを有する中間分子量成分を含有することが好ましい。このように、高分子量成分と低分子量成分とを併用することにより、耐オフセット性の向上と定着性（画像形成支持体に対する接着性）を両立することができる。
【０１３８】
ここに、ＧＰＣによる樹脂の分子量の測定方法としては、測定試料０．５〜５．０ｍｇ（具体的には１ｍｇ）に対してＴＨＦを１ｍｌ加え、マグネチックスターラーなどを用いて室温にて攪拌を行って十分に溶解させる。次いで、ポアサイズ０．４５〜０．５０μｍのメンブランフィルターで処理した後にＧＰＣへ注入する。
【０１３９】
ＧＰＣの測定条件としては、４０℃にてカラムを安定化させ、ＴＨＦを毎分１ｍｌの流速で流し、１ｍｇ／ｍｌの濃度の試料を約１００μｌ注入して測定する。カラムは、市販のポリスチレンジェルカラムを組み合わせて使用することが好ましい。例えば、昭和電工社製のＳｈｏｄｅｘ ＧＰＣ ＫＦ−８０１，８０２，８０３，８０４，８０５，８０６，８０７の組合せや、東ソー社製のＴＳＫｇｅｌＧ１０００Ｈ、Ｇ２０００Ｈ，Ｇ３０００Ｈ，Ｇ４０００Ｈ，Ｇ５０００Ｈ，Ｇ６０００Ｈ，Ｇ７０００Ｈ，ＴＳＫ ｇｕａｒｄ ｃｏｌｕｍｎの組合せなどを挙げることができる。また、検出器としては、屈折率検出器（ＩＲ検出器）またはＵＶ検出器を用いるとよい。試料の分子量測定では、試料の有する分子量分布を単分散のポリスチレン標準粒子を用いて作成した検量線を用いて算出する。検量線作成用のポリスチレンとしては１０点程度用いるとよい。
【０１４０】
以下、樹脂粒子の構成材料および調製方法（重合方法）について説明する。
〔単量体〕
樹脂粒子を得るために使用する重合性単量体としては、ラジカル重合性単量体を必須の構成成分とし、必要に応じて架橋剤を使用することができる。また、以下の酸性基を有するラジカル重合性単量体または塩基性基を有するラジカル重合性単量体を少なくとも１種類含有させることが好ましい。
（１）ラジカル重合性単量体：
ラジカル重合性単量体としては、特に限定されるものではなく従来公知のラジカル重合性単量体を用いることができる。また、要求される特性を満たすように、１種または２種以上のものを組み合わせて用いることができる。
【０１４１】
具体的には、芳香族系ビニル単量体、（メタ）アクリル酸エステル系単量体、ビニルエステル系単量体、ビニルエーテル系単量体、モノオレフィン系単量体、ジオレフィン系単量体、ハロゲン化オレフィン系単量体等を用いることができる。
【０１４２】
芳香族系ビニル単量体としては、例えば、スチレン、ｏ−メチルスチレン、ｍ−メチルスチレン、ｐ−メチルスチレン、ｐ−メトキシスチレン、ｐ−フェニルスチレン、ｐ−クロロスチレン、ｐ−エチルスチレン、ｐ−ｎ−ブチルスチレン、ｐ−ｔｅｒｔ−ブチルスチレン、ｐ−ｎ−ヘキシルスチレン、ｐ−ｎ−オクチルスチレン、ｐ−ｎ−ノニルスチレン、ｐ−ｎ−デシルスチレン、ｐ−ｎ−ドデシルスチレン、２，４−ジメチルスチレン、３，４−ジクロロスチレン等のスチレン系単量体およびその誘導体が挙げられる。
【０１４３】
（メタ）アクリル酸エステル系単量体としては、アクリル酸メチル、アクリル酸エチル、アクリル酸ブチル、アクリル酸−２−エチルヘキシル、アクリル酸シクロヘキシル、アクリル酸フェニル、メタクリル酸メチル、メタクリル酸エチル、メタクリル酸ブチル、メタクリル酸ヘキシル、メタクリル酸−２−エチルヘキシル、β−ヒドロキシアクリル酸エチル、γ−アミノアクリル酸プロピル、メタクリル酸ステアリル、メタクリル酸ジメチルアミノエチル、メタクリル酸ジエチルアミノエチル等が挙げられる。
【０１４４】
ビニルエステル系単量体としては、酢酸ビニル、プロピオン酸ビニル、ベンゾエ酸ビニル等が挙げられる。
【０１４５】
ビニルエーテル系単量体としては、ビニルメチルエーテル、ビニルエチルエーテル、ビニルイソブチルエーテル、ビニルフェニルエーテル等が挙げられる。
【０１４６】
モノオレフィン系単量体としては、エチレン、プロピレン、イソブチレン、１−ブテン、１−ペンテン、４−メチル−１−ペンテン等が挙げられる。
【０１４７】
ジオレフィン系単量体としては、ブタジエン、イソプレン、クロロプレン等が挙げられる。
【０１４８】
ハロゲン化オレフィン系単量体としては、塩化ビニル、塩化ビニリデン、臭化ビニル等が挙げられる。
（２）架橋剤：
架橋剤としては、トナーの特性を改良するためにラジカル重合性架橋剤を添加しても良い。ラジカル重合性架橋剤としては、ジビニルベンゼン、ジビニルナフタレン、ジビニルエーテル、ジエチレングリコールメタクリレート、エチレングリコールジメタクリレート、ポリエチレングリコールジメタクリレート、フタル酸ジアリル等の不飽和結合を２個以上有するものが挙げられる。
（３）酸性基または塩基性基を有するラジカル重合性単量体：
酸性基を有するラジカル重合性単量体または塩基性基を有するラジカル重合性単量体としては、例えば、カルボキシル基含有単量体、スルホン酸基含有単量体、第１級アミン、第２級アミン、第３級アミン、第４級アンモニウム塩等のアミン系の化合物を用いることができる。
【０１４９】
酸性基を有するラジカル重合性単量体としては、カルボン酸基含有単量体として、アクリル酸、メタクリル酸、フマール酸、マレイン酸、イタコン酸、ケイ皮酸、マレイン酸モノブチルエステル、マレイン酸モノオクチルエステル等が挙げられる。
【０１５０】
スルホン酸基含有単量体としては、スチレンスルホン酸、アリルスルホコハク酸、アリルスルホコハク酸オクチル等が挙げられる。
【０１５１】
これらは、ナトリウムやカリウム等のアルカリ金属塩あるいはカルシウムなどのアルカリ土類金属塩の構造であってもよい。
【０１５２】
塩基性基を有するラジカル重合性単量体としては、アミン系の化合物が挙げられ、ジメチルアミノエチルアクリレート、ジメチルアミノエチルメタクリレート、ジエチルアミノエチルアクリレート、ジエチルアミノエチルメタクリレート、および上記４化合物の４級アンモニウム塩、３−ジメチルアミノフェニルアクリレート、２−ヒドロキシ−３−メタクリルオキシプロピルトリメチルアンモニウム塩、アクリルアミド、Ｎ−ブチルアクリルアミド、Ｎ，Ｎ−ジブチルアクリルアミド、ピペリジルアクリルアミド、メタクリルアミド、Ｎ−ブチルメタクリルアミド、Ｎ−オクタデシルアクリルアミド；ビニルピリジン、ビニルピロリドン；ビニルＮ−メチルピリジニウムクロリド、ビニルＮ-エチルピリジニウムクロリド、Ｎ，Ｎ−ジアリルメチルアンモニウムクロリド、Ｎ，Ｎ−ジアリルエチルアンモニウムクロリド等を挙げることができる。
【０１５３】
本発明に用いられるラジカル重合性単量体としては、酸性基を有するラジカル重合性単量体または塩基性基を有するラジカル重合性単量体が単量体全体の０．１〜１５質量％使用することが好ましく、ラジカル重合性架橋剤はその特性にもよるが、全ラジカル重合性単量体に対して０．１〜１０質量％の範囲で使用することが好ましい。
〔連鎖移動剤〕
樹脂粒子の分子量を調整することを目的として、一般的に用いられる連鎖移動剤を用いることが可能である。
【０１５４】
連鎖移動剤としては、特に限定されるものではなく例えばオクチルメルカプタン、ドデシルメルカプタン、ｔｅｒｔ−ドデシルメルカプタン等のメルカプタン、ｎ−オクチル−３−メルカプトプロピオン酸エステル、ターピノーレン、四臭化炭素およびα−メチルスチレンダイマー等が使用される。
〔重合開始剤〕
本発明に用いられるラジカル重合開始剤は水溶性であれば適宜使用が可能である。例えば過硫酸塩（過硫酸カリウム、過硫酸アンモニウム等）、アゾ系化合物（４，４′−アゾビス４−シアノ吉草酸及びその塩、２，２′−アゾビス（２−アミジノプロパン）塩等）、パーオキシド化合物等が挙げられる。
【０１５５】
更に上記ラジカル性重合開始剤は、必要に応じて還元剤と組み合わせレドックス系開始剤とする事が可能である。レドックス系開始剤を用いる事で、重合活性が上昇し重合温度の低下が図れ、更に重合時間の短縮が期待できる。
【０１５６】
重合温度は、重合開始剤の最低ラジカル生成温度以上であればどの温度を選択しても良いが例えば５０℃から９０℃の範囲が用いられる。但し、常温開始の重合開始剤、例えば過酸化水素−還元剤（アスコルビン酸等）の組み合わせを用いる事で、室温またはそれ以上の温度で重合する事も可能である。
〔界面活性剤〕
前述のラジカル重合性単量体を使用して重合を行うためには、界面活性剤を使用して水系媒体中に油滴分散を行う必要がある。この際に使用することのできる界面活性剤としては特に限定されるものでは無いが、下記のイオン性界面活性剤を好適なものの例として挙げることができる。
【０１５７】
イオン性界面活性剤としては、スルホン酸塩（ドデシルベンゼンスルホン酸ナトリウム、アリールアルキルポリエーテルスルホン酸ナトリウム、３，３−ジスルホンジフェニル尿素−４，４−ジアゾ−ビス−アミノ−８−ナフトール−６−スルホン酸ナトリウム、オルト−カルボキシベンゼン−アゾ−ジメチルアニリン、２，２，５，５−テトラメチル−トリフェニルメタン−４，４−ジアゾ−ビス−β−ナフトール−６−スルホン酸ナトリウム等）、硫酸エステル塩（ドデシル硫酸ナトリウム、テトラデシル硫酸ナトリウム、ペンタデシル硫酸ナトリウム、オクチル硫酸ナトリウム等）、脂肪酸塩（オレイン酸ナトリウム、ラウリン酸ナトリウム、カプリン酸ナトリウム、カプリル酸ナトリウム、カプロン酸ナトリウム、ステアリン酸カリウム、オレイン酸カルシウム等）が挙げられる。
【０１５８】
また、ノニオン性界面活性剤も使用することができる。具体的には、ポリエチレンオキサイド、ポリプロピレンオキサイド、ポリプロピレンオキサイドとポリエチレンオキサイドの組み合わせ、ポリエチレングリコールと高級脂肪酸とのエステル、アルキルフェノールポリエチレンオキサイド、高級脂肪酸とポリエチレングリコールのエステル、高級脂肪酸とポリプロピレンオキサイドのエステル、ソルビタンエステル等を挙げることができる。
〈着色剤〉
本発明のトナーを構成する着色剤としては無機顔料、有機顔料、染料を挙げることができる。
【０１５９】
無機顔料としては、従来公知のものを用いることができる。具体的な無機顔料を以下に例示する。
【０１６０】
黒色の顔料としては、例えば、ファーネスブラック、チャンネルブラック、アセチレンブラック、サーマルブラック、ランプブラック等のカーボンブラック、更にマグネタイト、フェライト等の磁性粉も用いられる。
【０１６１】
これらの無機顔料は所望に応じて単独または複数を選択併用する事が可能である。また顔料の添加量は重合体に対して２〜２０質量％であり、好ましくは３〜１５質量％が選択される。
【０１６２】
磁性トナーとして使用する際には、前述のマグネタイトを添加することができる。この場合には所定の磁気特性を付与する観点から、トナー中に２０〜６０質量％添加することが好ましい。
【０１６３】
有機顔料及び染料としても従来公知のものを用いることができる。具体的な有機顔料及び染料を以下に例示する。
【０１６４】
マゼンタまたはレッド用の顔料としては、Ｃ．Ｉ．ピグメントレッド２、Ｃ．Ｉ．ピグメントレッド３、Ｃ．Ｉ．ピグメントレッド５、Ｃ．Ｉ．ピグメントレッド６、Ｃ．Ｉ．ピグメントレッド７、Ｃ．Ｉ．ピグメントレッド１５、Ｃ．Ｉ．ピグメントレッド１６、Ｃ．Ｉ．ピグメントレッド４８：１、Ｃ．Ｉ．ピグメントレッド５３：１、Ｃ．Ｉ．ピグメントレッド５７：１、Ｃ．Ｉ．ピグメントレッド１２２、Ｃ．Ｉ．ピグメントレッド１２３、Ｃ．Ｉ．ピグメントレッド１３９、Ｃ．Ｉ．ピグメントレッド１４４、Ｃ．Ｉ．ピグメントレッド１４９、Ｃ．Ｉ．ピグメントレッド１６６、Ｃ．Ｉ．ピグメントレッド１７７、Ｃ．Ｉ．ピグメントレッド１７８、Ｃ．Ｉ．ピグメントレッド２２２等が挙げられる。
【０１６５】
オレンジまたはイエロー用の顔料としては、Ｃ．Ｉ．ピグメントオレンジ３１、Ｃ．Ｉ．ピグメントオレンジ４３、Ｃ．Ｉ．ピグメントイエロー１２、Ｃ．Ｉ．ピグメントイエロー１３、Ｃ．Ｉ．ピグメントイエロー１４、Ｃ．Ｉ．ピグメントイエロー１５、Ｃ．Ｉ．ピグメントイエロー１７、Ｃ．Ｉ．ピグメントイエロー９３、Ｃ．Ｉ．ピグメントイエロー９４、Ｃ．Ｉ．ピグメントイエロー１３８、Ｃ．Ｉ．ピグメントイエロー１８０、Ｃ．Ｉ．ピグメントイエロー１８５、Ｃ．Ｉ．ピグメントイエロー１５５、Ｃ．Ｉ．ピグメントイエロー１５６等が挙げられる。
【０１６６】
グリーンまたはシアン用の顔料としては、Ｃ．Ｉ．ピグメントブルー１５、Ｃ．Ｉ．ピグメントブルー１５：２、Ｃ．Ｉ．ピグメントブルー１５：３、Ｃ．Ｉ．ピグメントブルー１６、Ｃ．Ｉ．ピグメントブルー６０、Ｃ．Ｉ．ピグメントグリーン７等が挙げられる。
【０１６７】
また、染料としてはＣ．Ｉ．ソルベントレッド１、同４９、同５２、同５８、同６３、同１１１、同１２２、Ｃ．Ｉ．ソルベントイエロー１９、同４４、同７７、同７９、同８１、同８２、同９３、同９８、同１０３、同１０４、同１１２、同１６２、Ｃ．Ｉ．ソルベントブルー２５、同３６、同６０、同７０、同９３、同９５等を用いる事ができ、またこれらの混合物も用いる事ができる。
【０１６８】
これらの有機顔料及び染料は所望に応じて単独または複数を選択併用する事が可能である。また顔料の添加量は重合体に対して２〜２０質量％であり、好ましくは３〜１５質量％が選択される。
【０１６９】
着色剤は表面改質して使用することもできる。その表面改質剤としては、従来公知のものを使用することができ、具体的にはシランカップリング剤、チタンカップリング剤、アルミニウムカップリング剤等が好ましく用いることができる。
〈外添剤〉
本発明のトナーには、前記した塩析／融着させて得られた着色粒子に流動性、帯電性の改良およびクリーニング性の向上などの目的で、いわゆる外添剤を添加して使用することができる。これら外添剤としては特に限定されるものでは無く、種々の無機微粒子、有機微粒子及び滑剤を使用することができる。
【０１７０】
無機微粒子としては、従来公知のものを使用することができる。具体的には、シリカ、チタン、アルミナ微粒子等が好ましく用いることができる。これら無機微粒子としては疎水性のものが好ましい。具体的には、シリカ微粒子として、例えば日本アエロジル社製の市販品Ｒ−８０５、Ｒ−９７６、Ｒ−９７４、Ｒ−９７２、Ｒ−８１２、Ｒ−８０９、ヘキスト社製のＨＶＫ−２１５０、Ｈ−２００、キャボット社製の市販品ＴＳ−７２０、ＴＳ−５３０、ＴＳ−６１０、Ｈ−５、ＭＳ−５等が挙げられる。
【０１７１】
チタン微粒子としては、例えば、日本アエロジル社製の市販品Ｔ−８０５、Ｔ−６０４、テイカ社製の市販品ＭＴ−１００Ｓ、ＭＴ−１００Ｂ、ＭＴ−５００ＢＳ、ＭＴ−６００、ＭＴ−６００ＳＳ、ＪＡ−１、富士チタン社製の市販品ＴＡ−３００ＳＩ、ＴＡ−５００、ＴＡＦ−１３０、ＴＡＦ−５１０、ＴＡＦ−５１０Ｔ、出光興産社製の市販品ＩＴ−Ｓ、ＩＴ−ＯＡ、ＩＴ−ＯＢ、ＩＴ−ＯＣ等が挙げられる。
【０１７２】
アルミナ微粒子としては、例えば、日本アエロジル社製の市販品ＲＦＹ−Ｃ、Ｃ−６０４、石原産業社製の市販品ＴＴＯ−５５等が挙げられる。
【０１７３】
また、有機微粒子としては数平均一次粒子径が１０〜２０００ｎｍ程度の球形の有機微粒子を使用することができる。このものとしては、スチレンやメチルメタクリレートなどの単独重合体やこれらの共重合体を使用することができる。
【０１７４】
滑剤には、例えばステアリン酸の亜鉛、アルミニウム、銅、マグネシウム、カルシウム等の塩、オレイン酸の亜鉛、マンガン、鉄、銅、マグネシウム等の塩、パルミチン酸の亜鉛、銅、マグネシウム、カルシウム等の塩、リノール酸の亜鉛、カルシウム等の塩、リシノール酸の亜鉛、カルシウムなどの塩等の高級脂肪酸の金属塩が挙げられる。
【０１７５】
これら外添剤の添加量は、トナーに対して０．１〜５質量％が好ましい。
本発明のトナーは、離型剤及び／又は結晶性ポリエステルを含有する樹脂粒子と、着色剤粒子とを水系媒体中で塩析／融着させて得られる会合型の着色粒子を基本成分としている。
【０１７６】
このように、離型剤及び／又は結晶性ポリエステルを含有する樹脂粒子を塩析／融着させることで、離型剤及び／又は結晶性ポリエステルが微細に分散されたトナーを得ることができる。
【０１７７】
そして、本発明のトナーは、その製造時から表面に凹凸がある形状を有しており、さらに、樹脂粒子と着色剤粒子とを水系媒体中で融着して得られる会合型のトナーであるために、トナー粒子間における形状および表面性の差がきわめて小さく、結果として表面性が均一となりやすい。このためにトナー間での定着性に差異を生じにくく、定着性も良好に保つことができるものである。
〈トナーの製造工程〉
本発明のトナーを製造する方法の一例としては、
（１）離型剤及び／又は結晶性ポリエステルを単量体中に溶解して単量体溶液を調製する溶解工程、
（２）得られる単量体溶液を水系媒体中に分散する分散工程、
（３）得られる単量体溶液の水系分散系を重合処理することにより、離型剤及び／又は結晶性ポリエステルを含有する樹脂粒子の分散液（ラテックス）を調製する重合工程、
（４）得られる樹脂粒子と、前記着色剤粒子とを水系媒体中で塩析／融着させて会合着色粒子（トナー粒子）を得る塩析／融着工程、
（５）得られる会合着色粒子を水系媒体中より濾別し、当該会合着色粒子から界面活性剤などを洗浄除去する濾過・洗浄工程、
（６）洗浄処理された会合着色粒子の乾燥工程から構成され、
（７）乾燥処理された会合着色粒子に外添剤を添加する外添剤添加工程が含まれていてもよい。
〔溶解工程〕
離型剤及び／又は結晶性ポリエステルを単量体中に溶解する方法としては特に限定されるものではない。
【０１７８】
単量体への離型剤の溶解量としては、最終的に得られるトナーにおける離型剤の含有割合が１〜３０質量％、好ましくは２〜２０質量％、更に好ましくは３〜１５質量％となる量とされる。
【０１７９】
単量体への結晶性ポリエステルの溶解量としては、最終的に得られるトナーにおける結晶性ポリエステルの含有割合が１〜５０質量％、好ましくは５〜４０質量％、更に好ましくは５〜３０質量％となる量とされる。
【０１８０】
なお、この単量体溶液中に、油溶性重合開始剤および他の油溶性の成分を添加することもできる。
〔分散工程〕
単量体溶液を水系媒体中に分散させる方法としては、特に限定されるものではないが、機械的エネルギーにより分散させる方法が好ましく、特に、臨界ミセル濃度以下の濃度の界面活性剤を溶解してなる水系媒体中に、機械的エネルギーを利用して単量体溶液を油滴分散させること（ミニエマルジョン法における必須の態様）が好ましい。
【０１８１】
ここに、機械的エネルギーによる油滴分散を行うための分散機としては、特に限定されるものではないが、例えば「クレアミックス」、超音波分散機、機械式ホモジナイザー、マントンゴーリンおよび圧力式ホモジナイザーなどを挙げることができる。また、分散粒子径としては、１０〜１０００ｎｍとされ、好ましくは３０〜３００ｎｍとされる。
〔重合工程〕
重合工程においては、基本的には従来公知の重合法（乳化重合法、懸濁重合法、シード重合法などの造粒重合法）を採用することができる。
【０１８２】
好ましい重合法の一例としては、ミニエマルジョン法、すなわち、臨界ミセル濃度以下の濃度の界面活性剤を溶解してなる水系媒体中に、機械的エネルギーを利用して単量体溶液を油滴分散させて得られる分散液に水溶性重合開始剤を添加して、ラジカル重合させる方法を挙げることができる。
〔塩析／融着工程〕
塩析／融着工程においては、上記の重合工程により得られる樹脂粒子の分散液に着色剤粒子の分散液を添加し、前記樹脂粒子と、前記着色剤粒子とを水系媒体中で塩析／融着させ、着色粒子（トナー粒子）を得る。
【０１８３】
また、当該塩析／融着工程においては、樹脂粒子および着色剤粒子とともに、荷電制御剤などの内添剤粒子なども融着させることもできる。
【０１８４】
さらに、当該塩析／融着工程においては、離型剤及び／又は結晶性ポリエステルを含有する樹脂粒子とともに、これらを含有しない樹脂粒子を融着させることもできる。
【０１８５】
ここに、好適な態様として、離型剤及び／又は結晶性ポリエステルを含有する中間分子量の樹脂粒子（ＭＰ）と、低分子量の樹脂粒子（ＬＰ）と、高分子量の樹脂粒子（ＨＰ）と、着色剤粒子とを塩析／融着させ、着色粒子を得る方法を挙げることができる。
【０１８６】
離型剤及び／又は結晶性ポリエステルを中間分子量の樹脂粒子（ＭＰ）のみに含有させることにより、当該中間分子量の樹脂粒子（ＭＰ）による優れた耐オフセット性／定着性が発現されるとともに、高分子量の樹脂粒子（ＨＰ）により付与される耐オフセット性および巻き付き防止性、低分子量の樹脂粒子（ＬＰ）により付与される好適な定着性が損なわれることがない。
【０１８７】
塩析／融着工程における「水系媒体」とは、主成分（５０質量％以上）が水からなるものをいう。ここに、水以外の成分としては、水に溶解する有機溶媒を挙げることができ、例えばメタノール、エタノール、イソプロパノール、ブタノール、アセトン、メチルエチルケトン、テトラヒドロフランなどが挙げられる。これらのうち、樹脂を溶解しない有機溶媒であるメタノール、エタノール、イソプロパノール、ブタノールのようなアルコール系有機溶媒が特に好ましい。
【０１８８】
塩析／融着工程に使用される着色剤粒子は、着色剤を水系媒体中に分散することにより調製することができる。着色剤の分散処理は、水中で界面活性剤濃度を臨界ミセル濃度（ＣＭＣ）以上にした状態で行われる。
【０１８９】
着色剤の分散処理に使用する分散機は特に限定されないが、好ましくは、「クレアミックス」、超音波分散機、機械的ホモジナイザー、マントンゴーリンや圧力式ホモジナイザー等の加圧分散機、サンドグラインダー、ゲッツマンミルやダイヤモンドファインミル等の媒体型分散機が挙げられる。また、使用される界面活性剤としては、前述の界面活性剤と同様のものを挙げることができる。
【０１９０】
なお、着色剤（粒子）は表面改質されていてもよい。着色剤の表面改質法は、溶媒中に着色剤を分散させ、その分散液中に表面改質剤を添加し、この系を昇温することにより反応させる。反応終了後、着色剤を濾別し、同一の溶媒で洗浄ろ過を繰り返した後、乾燥することにより、表面改質剤で処理された着色剤（顔料）が得られる。
【０１９１】
塩析／融着法は、樹脂粒子と着色剤粒子とが存在している水中に、アルカリ金属塩および／またはアルカリ土類金属塩等からなる塩析剤を臨界凝集濃度以上の凝集剤として添加し、次いで、前記樹脂粒子のガラス転移点以上に加熱することで塩析を進行させると同時に融着を行う工程である。この工程では、水に無限溶解する有機溶媒を添加してもよい。
【０１９２】
ここで、塩析剤であるアルカリ金属塩及びアルカリ土類金属塩は、アルカリ金属として、リチウム、カリウム、ナトリウム等が挙げられ、アルカリ土類金属として、マグネシウム、カルシウム、ストロンチウム、バリウムなどが挙げられ、好ましくはカリウム、ナトリウム、マグネシウム、カルシウム、バリウムが挙げられる。また塩を構成するものとしては、塩素塩、臭素塩、沃素塩、炭酸塩、硫酸塩等が挙げられる。
【０１９３】
さらに、前記水に無限溶解する有機溶媒としては、メタノール、エタノール、１−プロパノール、２−プロパノール、エチレングリコール、グリセリン、アセトン等があげられるが、炭素数が３以下のメタノール、エタノール、１−プロパノール、２−プロパノールのアルコールが好ましく、特に、２−プロパノールが好ましい。
【０１９４】
塩析／融着工程においては、塩析剤を添加した後に放置する時間（加熱を開始するまでの時間）をできるだけ短くすることが好ましい。すなわち、塩析剤を添加した後、樹脂粒子および着色剤粒子の分散液の加熱をできるだけ速やかに開始し、樹脂粒子のガラス転移温度以上とすることが好ましい。
【０１９５】
この理由としては明確ではないが、塩析した後の放置時間によって、粒子の凝集状態が変動し、粒径分布が不安定になったり、融着させたトナーの表面性が変動したりする問題が発生する。
【０１９６】
加熱を開始するまでの時間（放置時間）は、通常３０分以内とされ、好ましくは１０分以内である。
【０１９７】
塩析剤を添加する温度は特に限定されないが、樹脂粒子のガラス転移温度以下であることが好ましい。
【０１９８】
また、塩析／融着工程においては、加熱により速やかに昇温させる必要があり、昇温速度としては、１℃／分以上とすることが好ましい。昇温速度の上限は、特に限定されないが、急速な塩析／融着の進行による粗大着色粒子の発生を抑制する観点から１５℃／分以下とすることが好ましい。
【０１９９】
さらに、樹脂粒子および着色剤粒子の分散液が前記ガラス転移温度以上の温度に到達した後、当該分散液の温度を一定時間保持することにより、塩析／融着を継続させることが肝要である。これにより、着色粒子（トナー粒子）の成長（樹脂粒子および着色剤粒子の凝集）と、融着（粒子間の界面消失）とを効果的に進行させることができ、最終的に得られるトナーの耐久性を向上することができる。
【０２００】
また、会合着色粒子の成長を停止させた後に、加熱による融着を継続させてもよい。
〔濾過・洗浄工程〕
この濾過・洗浄工程では、上記の工程で得られた着色粒子（トナー粒子）の分散液から当該着色粒子を濾別する濾過処理と、濾別された着色粒子（ケーキ状の集合物）から界面活性剤や塩析剤などの付着物を除去する洗浄処理とが施される。
【０２０１】
ここに、濾過処理方法としては、遠心分離法、ヌッチェ等を使用して行う減圧濾過法、フィルタープレス等を使用して行う濾過法など特に限定されるものではない。
〔乾燥工程〕
この工程は、洗浄処理された着色粒子（トナー粒子）を乾燥処理する工程である。
【０２０２】
この工程で使用される乾燥機としては、スプレードライヤー、真空凍結乾燥機、減圧乾燥機などを挙げることができ、静置棚乾燥機、移動式棚乾燥機、流動層乾燥機、回転式乾燥機、攪拌式乾燥機などを使用することが好ましい。
【０２０３】
乾燥処理された着色粒子（トナー粒子）の水分は、５質量％以下であることが好ましく、更に好ましくは２質量％以下とされる。
【０２０４】
なお、乾燥処理された着色粒子同士が、弱い粒子間引力で凝集している場合には、当該凝集体を解砕処理してもよい。ここに、解砕処理装置としては、ジェットミル、ヘンシェルミキサー、コーヒーミル、フードプロセッサー等の機械式の解砕装置を使用することができる。
〔外添剤の添加工程〕
この工程は、乾燥処理された着色粒子（トナー粒子）に外添剤を添加する工程である。
【０２０５】
外添剤を添加するために使用される装置としては、タービュラーミキサー、ヘンシエルミキサー、ナウターミキサー、Ｖ型混合機などの種々の公知の混合装置を挙げることができる。
【０２０６】
本発明のトナー粒子は、着色剤、離型剤、結晶性ポリエステル以外にトナー用材料として種々の機能を付与することのできる材料を加えてもよい。具体的には荷電制御剤等が挙げられる。これらの成分は前述の塩析／融着段階で樹脂粒子と着色剤粒子と同時に添加し、トナー中に包含する方法、樹脂粒子自体に添加する方法等種々の方法で添加することができる。
【０２０７】
荷電制御剤も同様に種々の公知のもので、かつ水中に分散することができるものを使用することができる。具体的には、ニグロシン系染料、ナフテン酸または高級脂肪酸の金属塩、アルコキシル化アミン、第４級アンモニウム塩化合物、アゾ系金属錯体、サリチル酸金属塩あるいはその金属錯体等が挙げられる。
【０２０８】
本発明のトナーは、セミグロス画像を形成するために好適に使用される。
ここに、「セミグロス画像」とは、標準光沢度が１７〜３７である画像をいうものとする。本発明において標準光沢度とは、画像形成材料（トナー）が画像形成支持体を９０％以上被覆している画像部分において、ＪＩＳ−Ｚ８７４１−１９８３方法２により、入射角７５°にてグロスメーターＶＧＳ−１Ｄ（日本電色工業（株）社製）により測定した値で表す。画像形成材料による画像形成支持体の被覆割合の測定は、高速カラー画像解析装置ＳＰＩＣＣＡ（日本アビオニクス社製）を用いて行った。
【０２０９】
本発明においてセミグロス画像の標準光沢度は１７〜３７とされ、好ましくは１７〜２７とされる。標準光沢度が１７未満では、画像の鮮やかさに欠け、十分な質感が得られない。一方、標準光沢度が３７を超えると、表面正反射光成分が大きすぎ、十分な質感が得られず、現実性（リアリティ）が不足する。更に、表面が平滑であると内部への入射光量が大きくなり、着色剤の劣化が生じ易く、経時的な画像劣化が生じる。着色剤の劣化に対しては、特に標準光沢度が２７以下であることが好ましい。
〈現像剤〉
本発明のトナーは、一成分現像剤でも二成分現像剤として用いてもよい。
【０２１０】
一成分現像剤として用いる場合は、非磁性一成分現像剤、あるいはトナー中に０．１〜０．５μｍ程度の磁性粒子を含有させ磁性一成分現像剤としたものがあげられ、いずれも使用することができる。
【０２１１】
また、キャリアと混合して二成分現像剤として用いることができる。この場合は、キャリアの磁性粒子として、鉄、フェライト、マグネタイト等の金属、それらの金属とアルミニウム、鉛等の金属との合金等の従来から公知の材料を用いることが出来る。特にフェライト粒子が好ましい。上記磁性粒子は、その体積平均粒径としては１５〜１００μｍ、より好ましくは２５〜８０μｍのものがよい。
【０２１２】
キャリアの体積平均粒径の測定は、代表的には湿式分散機を備えたレーザ回折式粒度分布測定装置「ヘロス（ＨＥＬＯＳ）」（シンパティック（ＳＹＭＰＡＴＥＣ）社製）により測定することができる。
【０２１３】
キャリアは、磁性粒子が更に樹脂により被覆されているもの、あるいは樹脂中に磁性粒子を分散させたいわゆる樹脂分散型キャリアが好ましい。コーティング用の樹脂組成としては、特に限定は無いが、例えば、オレフィン系樹脂、スチレン系樹脂、スチレン−アクリル系樹脂、シリコーン系樹脂、エステル系樹脂或いはフッ素含有重合体系樹脂等が用いられる。また、樹脂分散型キャリアを構成するための樹脂としては、特に限定されず公知のものを使用することができ、例えば、スチレン−アクリル系樹脂、ポリエステル樹脂、フッ素系樹脂、フェノール樹脂等を使用することができる。
【０２１４】
【実施例】
以下、本発明の実施例を説明するが、本発明はこれらの実施例に限定されるものではない。なお、以下において「部」とは「質量部」を意味する。
〔調製例ＨＰ−１〕
攪拌装置、温度センサー、冷却管、窒素導入装置を取り付けた５０００ｍｌのセパラブルフラスコに、アニオン系界面活性剤（ドデシルスルフォン酸ナトリウム：ＳＤＳ）７．０８ｇをイオン交換水２７６０ｇに溶解させた界面活性剤溶液（水系媒体）を仕込み、窒素気流下２３０ｒｐｍの攪拌速度で攪拌しながら、内温を８０℃に昇温させた。
【０２１５】
この界面活性剤溶液に、重合開始剤（過硫酸カリウム：ＫＰＳ）０．４２ｇをイオン交換水２００ｇに溶解させた開始剤溶液を添加し、温度を７５℃とした後、スチレン１１５．１ｇ、ｎ−ブチルアクリレート４２．０ｇ、メタクリル酸１０．９ｇからなる単量体混合液を１時間かけて滴下し、この系を７５℃で２時間にわたり加熱・攪拌することにより、ラテックス（高分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＨＰ−１）」とする。
【０２１６】
このラテックス（ＨＰ−１）を構成する樹脂粒子のピーク分子量は５１８，０００であった。また、この樹脂粒子の重量平均粒径は１０５ｎｍであった。
〔調製例ＨＰ−２〕
反応温度を８５℃に変更したこと以外は調製例ＨＰ−１と同様にしてラテックス（高分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＨＰ−２）」とする。
【０２１７】
このラテックス（ＨＰ−２）を構成する樹脂粒子のピーク分子量は４２１，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＨＰ−３〕
重合開始剤（ＫＰＳ）の添加量を０．８４ｇに変更したこと以外は調製例ＨＰ−１と同様にしてラテックス（高分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＨＰ−３）」とする。
【０２１８】
このラテックス（ＨＰ−３）を構成する樹脂粒子のピーク分子量は３１６，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＨＰ−４〕
過硫酸カリウム（ＫＰＳ）の添加量を０．８４ｇに変更し、反応温度を９０℃に変更したこと以外は調製例ＨＰ−１と同様にしてラテックス（高分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＨＰ−４）」とする。
【０２１９】
このラテックス（ＨＰ−４）を構成する樹脂粒子のピーク分子量は１９３，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−１〕
攪拌装置を取り付けたフラスコにて、上記式１９）で表される化合物（以下、「例示化合物（１９）」という。）７２．０ｇを、スチレン３８３．６ｇ、ｎ−ブチルアクリレート１４０．０ｇ、メタクリル酸３６．４ｇ、ドデシルメルカプタン５．６ｇからなる単量体混合液に添加し、８０℃に加温し溶解させて単量体溶液を調製した。
【０２２０】
一方、攪拌装置、温度センサー、冷却管、窒素導入装置を取り付けた５０００ｍｌのセパラブルフラスコに、アニオン系界面活性剤（ＳＤＳ）１．６ｇをイオン交換水２０００ｇに溶解させた界面活性剤溶液（水系媒体）を仕込み、内温を８０℃に昇温させた。
【０２２１】
次いで、循環経路を有する機械式分散機「クレアミックス」（エム・テクニック（株）製）により、前記界面活性剤溶液（８０℃）中に、前記単量体溶液（８０℃）を混合分散させ、均一な分散粒子径を有する乳化粒子（油滴）の分散液を調製した。
【０２２２】
次いで、この分散液に、重合開始剤（ＫＰＳ）１９．１ｇをイオン交換水２４０ｇに溶解させた開始剤溶液と、イオン交換水７５０ｇとを添加し、この系を８０℃にて３時間にわたり加熱・攪拌することにより重合を行い、ラテックス（例示化合物（１９）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−１）」とする。
【０２２３】
このラテックス（ＭＰ−１）を構成する樹脂粒子のピーク分子量は１０３，０００であった。また、この樹脂粒子の重量平均粒径は１０８ｎｍであった。
〔調製例ＭＰ−２〕
単量体混合液を構成するドデシルメルカプタンの量を８．３ｇに変更したこと以外は調製例ＭＰ−１と同様にして、ラテックス（例示化合物（１９）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−２）」とする。
【０２２４】
このラテックス（ＭＰ−２）を構成する樹脂粒子のピーク分子量は８１，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−３〕
単量体混合液への例示化合物（１９）の添加量を１４４．０ｇに変更したこと以外は調製例ＭＰ−１と同様にして、ラテックス（例示化合物（１９）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−３）」とする。
【０２２５】
このラテックス（ＭＰ−３）を構成する樹脂粒子のピーク分子量は１０３，０００であった。また、この樹脂粒子の重量平均粒径は１１５ｎｍであった。
〔調製例ＭＰ−４〕
例示化合物（１９）に代えて、上記式２１）で表される化合物（以下、「例示化合物（２１）」という。）７２．０ｇを単量体混合液へ添加したこと以外は調製例ＭＰ−１と同様にして、ラテックス（例示化合物（２１）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−４）」とする。
【０２２６】
このラテックス（ＭＰ−４）を構成する樹脂粒子のピーク分子量は１０２，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−５〕
例示化合物（１９）に代えて、上記式１８）で表される化合物（以下、「例示化合物（１８）」という。）７２．０ｇを単量体混合液へ添加したこと以外は調製例ＭＰ−１と同様にして、ラテックス（例示化合物（１８）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−５）」とする。
【０２２７】
このラテックス（ＭＰ−５）を構成する樹脂粒子のピーク分子量は１０２，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−６〕
例示化合物（１９）に代えて、下記表１に示す結晶性ポリエステル（１）８０．０ｇを単量体混合液へ添加したこと以外は調製例ＭＰ−１と同様にして、ラテックス（結晶性ポリエステル（１）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−６）」とする。
【０２２８】
このラテックス（ＭＰ−６）を構成する樹脂粒子のピーク分子量は１０５，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−７〕
単量体混合液を構成するドデシルメルカプタンの量を８．３ｇに変更したこと以外は調製例ＭＰ−６と同様にして、ラテックス（結晶性ポリエステル（１）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−７）」とする。
【０２２９】
このラテックス（ＭＰ−７）を構成する樹脂粒子のピーク分子量は７９，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−８〕
結晶性ポリエステル（１）に代えて、下記表１に示す結晶性ポリエステル（２）８０．０ｇを単量体混合液へ添加したこと以外は調製例ＭＰ−６と同様にして、ラテックス（結晶性ポリエステル（２）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−８）」とする。
【０２３０】
このラテックス（ＭＰ−８）を構成する樹脂粒子のピーク分子量は１０４，０００であった。また、この樹脂粒子の重量平均粒径は１１５ｎｍであった。
〔調製例ＭＰ−９〕
結晶性ポリエステル（１）に代えて、下記表１に示す結晶性ポリエステル（３）８０．０ｇを単量体混合液へ添加したこと以外は調製例ＭＰ−６と同様にして、ラテックス（結晶性ポリエステル（３）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−９）」とする。
【０２３１】
このラテックス（ＭＰ−９）を構成する樹脂粒子のピーク分子量は１０４，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−１０〕
結晶性ポリエステル（１）に代えて、下記表１に示す結晶性ポリエステル（４）８０．０ｇを単量体混合液へ添加したこと以外は調製例ＭＰ−６と同様にして、ラテックス（結晶性ポリエステル（４）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−１０）」とする。
【０２３２】
このラテックス（ＭＰ−１０）を構成する樹脂粒子のピーク分子量は１０１，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−１１〕
結晶性ポリエステル（１）に代えて、下記表１に示す結晶性ポリエステル（５）８０．０ｇを単量体混合液へ添加したこと以外は調製例ＭＰ−６と同様にして、ラテックス（結晶性ポリエステル（５）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−１１）」とする。
【０２３３】
このラテックス（ＭＰ−１１）を構成する樹脂粒子のピーク分子量は１００，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−１２〕
単量体混合液への結晶性ポリエステル（１）の添加量を９０．０ｇに変更したこと以外は調製例ＭＰ−６と同様にして、ラテックス（結晶性ポリエステル（１）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−１２）」とする。
【０２３４】
このラテックス（ＭＰ−１２）を構成する樹脂粒子のピーク分子量は１０３，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
〔調製例ＭＰ−１３〕
単量体混合液への結晶性ポリエステル（１）の添加量を７０．０ｇに変更したこと以外は調製例ＭＰ−６と同様にして、ラテックス（結晶性ポリエステル（１）を含有する中間分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＭＰ−１３）」とする。
【０２３５】
このラテックス（ＭＰ−１３）を構成する樹脂粒子のピーク分子量は１０７，０００であった。また、この樹脂粒子の重量平均粒径は１１０ｎｍであった。
【０２３６】
【表１】

【０２３７】
〔調製例ＬＰ−１〕
攪拌装置、温度センサー、冷却管、窒素導入装置を取り付けたフラスコに、アニオン系界面活性剤（ＳＤＳ）６０ｇをイオン交換水５０００ｇに溶解させた界面活性剤溶液（水系媒体）を仕込み、窒素気流下２３０ｒｐｍの攪拌速度で攪拌しながら、内温を８０℃に昇温させた。
【０２３８】
この界面活性剤溶液に、重合開始剤（ＫＰＳ）２２．８ｇをイオン交換水２００ｇに溶解させた開始剤溶液を添加し、温度を８０℃に保った状態で、スチレン８５０ｇ、ブチルアクリレート２５２ｇ、メタクリル酸９８ｇ、ｔ−ドデシルメルカプタン３２ｇからなる単量体混合液を１時間かけて滴下し、この系を８０℃で２時間にわたり加熱・攪拌することにより、ラテックス（低分子量の樹脂粒子の分散液）を調製した。これを「ラテックス（ＬＰ−１）」とする。
【０２３９】
このラテックス（ＬＰ−１）を構成する樹脂粒子のピーク分子量は１８，０００であった。また、この樹脂粒子の重量平均粒径は１０５ｎｍであった。
〔着色粒子１の製造例〕
ｎ−ドデシル硫酸ナトリウム９０ｇをイオン交換水１６００ｍｌに攪拌溶解した。この溶液を攪拌しながら、カーボンブラック「モーガルＬ」（キャボット社製）２００ｇを徐々に添加し、次いで、高速回転するローターを備えた攪拌装置「クレアミックス」（エム・テクニック（株）製）を用いて分散処理することにより、着色剤粒子の分散液（以下、「着色剤分散液」という。）を調製した。この着色剤分散液における着色剤粒子の粒子径を、電気泳動光散乱光度計「ＥＬＳ−８００」（大塚電子社製）を用いて測定したところ、重量平均粒子径で１０１ｎｍであった。
【０２４０】
調製例ＨＰ−１で得られたラテックス（ＨＰ−１）３０００ｇと、調製例ＭＰ−１で得られたラテックス（ＭＰ−１）２５００ｇと、調製例ＬＰ−１で得られたラテックス（ＬＰ−１）６０００ｇと、イオン交換水２０００ｇと、着色剤分散液１８００ｇとを、温度センサー、冷却管、窒素導入装置、攪拌装置を取り付けた反応容器に入れ攪拌した。内温を３０℃に調整した後、この溶液に５ｍｏｌ／Ｌの水酸化ナトリウム水溶液を加えてｐＨを１１．０に調整した。次いで、塩化マグネシウム６水和物５２６ｇをイオン交換水７２０ｍｌに溶解した水溶液を、攪拌下、３０℃にて１０分間かけて添加した。３分間放置した後に昇温を開始し、この系を６分間かけて９０℃まで昇温した（昇温速度＝１０℃／分）。その状態で、「コールターカウンターＴＡ−II」にて会合粒子の粒径を測定し、体積平均粒径が６．５μｍになった時点で、塩化ナトリウム１１５０ｇをイオン交換水７０００ｍｌに溶解した水溶液を添加して粒子成長を停止させ、さらに、熟成処理として液温度８５℃にて２時間にわたり加熱攪拌することにより融着を継続させた。その後、８℃／分の条件で３０℃まで冷却し、塩酸を添加してｐＨを２．０に調整し、攪拌を停止した。生成した会合粒子を濾過し、イオン交換水で繰り返し洗浄し、その後、４０℃の温風で乾燥して着色粒子を得た。このようにして得られた着色粒子を「着色粒子１」とする。
〔着色粒子２〜１０および比較着色粒子Ｃ１の製造例〕
下記表２に示す処方に従って、使用したラテックスの種類（使用量は同じ）、熟成処理温度、熟成処理時間の少なくとも１つを変更したこと以外は着色粒子１と同様にして離型剤を含有する着色粒子を得た。このようにして得られた着色粒子を「着色粒子２」〜「着色粒子１０」、「比較用着色粒子Ｃ１」とする。
〔比較着色粒子Ｃ２の製造例〕
アニオン系界面活性剤（ＳＤＳ）０．５ｇをイオン交換水４００ｇに溶解させた界面活性剤溶液（８５℃）中に、加熱溶解させた例示化合物（１９）１４０ｇを超音波分散させた。この分散液を「離型剤分散液」とする。
【０２４１】
この離型剤分散液と、調製例ＨＰ−１で得られたラテックス（ＨＰ−１）３０００ｇと、調製例ＬＰ−１で得られたラテックス（ＬＰ−１）６０００ｇと、イオン交換水２０００ｇと、着色剤分散液１３００ｇとを、温度センサー、冷却管、窒素導入装置、攪拌装置を取り付けた反応容器に入れ攪拌し、熟成処理時間を４時間に変更したこと以外は製造例１Ｂｋと同様にして離型剤を含有する着色粒子を得た。このようにして得られた着色粒子を「比較用着色粒子Ｃ２」とする。
【０２４２】
【表２】

【０２４３】
〔着色粒子１１〜２３および比較着色粒子Ｃ３の製造例〕
下記表３に示す処方に従って、使用したラテックスの種類（使用量は同じ）、熟成処理温度、熟成処理時間の少なくとも１つを変更したこと以外は着色粒子１と同様にして結晶性ポリエステルを含有する着色粒子を得た。このようにして得られた着色粒子を「着色粒子１１」〜「着色粒子２３」、「比較用着色粒子Ｃ３」とする。
〔比較着色粒子Ｃ４〕
アニオン系界面活性剤（ＳＤＳ）５．０ｇをイオン交換水４０００ｇに溶解させた界面活性剤溶液（８５℃）中に、結晶性ポリエステル（１）２００ｇを超音波分散させた。この分散液を「結晶性ポリエステル分散液」とする。
【０２４４】
この結晶性ポリエステル分散液と、調製例ＨＰ−１で得られたラテックス（ＨＰ−１）３０００ｇと、調製例ＬＰ−１で得られたラテックス（ＬＰ−１）６０００ｇと、イオン交換水２０００ｇと、着色剤分散液１３００ｇとを、温度センサー、冷却管、窒素導入装置、攪拌装置を取り付けた反応容器に入れ攪拌し、熟成処理時間を４時間に変更したこと以外は着色粒子１と同様にして結晶性ポリエステルを含有する着色粒子を得た。このようにして得られた着色粒子を「比較用着色粒子Ｃ４」とする。
【０２４５】
【表３】

【０２４６】
以上のようにして得られた着色粒子１〜１０、比較用着色粒子Ｃ１〜Ｃ２；着色粒子１１〜２３、比較用着色粒子Ｃ３〜Ｃ４の各々について、形状特性および粒度分布特性を下記表４〜表５に示す。
【０２４７】
【表４】

【０２４８】
【表５】

【０２４９】
上記の着色粒子および比較用着色粒子の各々に、疎水性シリカ（数平均一次粒子径＝１０ｎｍ、疎水化度＝６３）を１．０質量％となる割合で添加するとともに、疎水性酸化チタン（数平均一次粒子径＝２５ｎｍ、疎水化度＝６０）を１．２質量％となる割合でそれぞれ添加し、ヘンシェルミキサーにより混合し、トナー１〜１０及び比較用トナーＣ１〜Ｃ２、トナー１１〜２３及び比較用トナーＣ３〜Ｃ４を作製した。
【０２５０】
なお、これらのトナー粒子の形状及び粒径は、対応する着色粒子と同じであり、疎水性シリカおよび疎水性酸化チタンの添加によっては、その形状および粒径は変化しない。
【０２５１】
次いで、疎水性シリカおよび疎水性酸化チタンが添加された着色粒子の各々と、シリコーン樹脂を被覆した体積平均粒径６０μｍのフェライトキャリアとを混合し、トナー濃度が６質量％の現像剤を調製した。これらの現像剤を、着色粒子１〜１０、比較用着色粒子Ｃ１〜Ｃ２；着色粒子１１〜２３、比較用着色粒子Ｃ３〜Ｃ４に対応して、現像剤１〜１０、比較用現像剤Ｃ１〜Ｃ２；現像剤１１〜２３、比較用現像剤Ｃ３〜Ｃ４とする。
〔定着装置の作製〕
（定着装置１群）
図３に示す構成に従って、中央部にヒーターを内蔵するアルミ合金からなる円筒状（外径＝２７．５ｍｍ、肉厚＝０．８ｍｍ）の芯金の表面を、厚み２０μｍで４フッ化エチレン−パーフロロアルキルビニルエーテル共重合樹脂（ＰＦＡ）により被覆することにより加熱ローラを構成し、鉄からなる外径２６ｍｍの円柱状の芯金の表面を５．０ｍｍの厚みでシリコーンゴムにより被覆し、さらに４フッ化エチレン−パーフロロアルキルビニルエーテル共重合樹脂（ＰＦＡ）よりなる導電性チューブ（厚み：５０μｍ）で被覆することにより加圧ローラを構成し、当該加熱ローラと当該加圧ローラとを１２７Ｎの総荷重により当接させて３．５ｍｍ幅の定着ニップ部を形成させた。そして、下記表２に従って、加熱ローラの表面における表面粗さＳｍが変更された複数の定着装置を作製した。これらを「定着装置１群」とする。
（定着装置２群）
加熱ローラを構成する芯金の表面を被覆する離型層を形成する材料として、カーボンフィラーが含有された４フッ化エチレン−パーフロロアルキルビニルエーテル共重合樹脂（ＰＦＡ）を用い、下記表２に従って加熱ローラの表面における表面粗さＳｍを変更したことの他は定着装置１群と同様の構成の複数の定着装置を作製した。これらを「定着装置２群」とする。
〈実写テスト〉
現像剤１〜３の各々について、常温常湿環境下（温度２５℃，相対湿度４５％）で複写画像を形成する実写テストを行うことにより、▲１▼耐オフセット性、▲２▼巻き付き防止特性について評価を行った。
【０２５２】
ここに、画像形成装置としては、デジタル複写機「Ｓｉｔｉｏｓ７０２０」（コニカ株式会社製）を使用し、これに上記の定着装置を搭載したものを使用して、記録材の搬送速度を１４０ｍｍ／ｓｅｃ、定着温度は加熱ローラの表面温度で制御すると共に（設定温度１７５℃）、記録材Ｐ（転写紙）としては６４ｇ／ｍ²のコピー用紙を使用した。
〔評価方法〕
（１）耐オフセット性：
グレースケールを先端に配したＡ３原稿を連続して２０コピー行ったときのオフセットに起因する画像汚れの発生の有無（発生なし：○、発生有り：×）を目視により観察した。
（２）巻き付き防止特性：
ベタ黒画像を有するＡ３原稿を連続して１０コピー行ったときの加熱ローラに対する用紙の巻き付き現象の発生の有無（発生なし：○、発生有り：×）を確認した。
【０２５３】
以上の結果を下記表６〜１５に示す。
【０２５４】
【表６】

【０２５５】
【表７】

【０２５６】
【表８】

【０２５７】
【表９】

【０２５８】
【表１０】

【０２５９】
【表１１】

【０２６０】
【表１２】

【０２６１】
【表１３】

【０２６２】
【表１４】

【０２６３】
【表１５】

【０２６４】
上記表中、Ｙ＝（２８０−２０×Ｄ）
以上のように、トナーとして結着樹脂中に離型剤を含有する樹脂粒子とを、塩析／融着させて得られる本発明の特定の形状係数等を有するトナーを使用し、当該トナー粒子の個数平均粒径との関係において、加熱ローラの表面における表面粗さが特定の条件を満足する本発明の画像形成装置によれば、耐オフセット性および巻き付き防止特性に優れ、画質の高い画像を形成することができる。これに対して、トナーとして結着樹脂中に離型剤を含有する樹脂粒子とを、塩析／融着させて得られる本発明の特定の形状係数等を有するトナーを用いた場合であっても、トナー粒子の個数平均粒径との関係において、加熱ローラの表面粗さが特定の条件を満足しない画像形成装置では、耐オフセット性または巻き付き防止特性に劣り、実用上問題がある。又、形状係数等が本発明の範囲を外れたトナー（Ｃ１〜Ｃ４）を用いた場合は耐オフセット性が低下し、巻き付きが発生しない範囲も狭くなっている。
【０２６５】
【発明の効果】
本発明の画像形成装置によれば、加熱源を有する回転体に対する記録材の巻き付き現象や、オフセット現象が発生しにくく、画質の高い画像を安定して形成することができる。
【図面の簡単な説明】
【図１】表面粗さ（凹凸の平均間隔）を説明するための粗さ曲線を示す説明図である。
【図２】本発明の画像形成装置の一例における構成の概略を示す説明図である。
【図３】本発明の画像形成装置に搭載される熱ローラ方式の定着装置の一例における構成の概略を示す説明図である。
【図４】本発明の画像形成装置に搭載される熱定着ベルト方式の定着装置の一例における構成の概略を示す説明図である。
【図５】（ａ）は、角のないトナー粒子の投影像を示す説明図であり、（ｂ）および（ｃ）は、それぞれ角のあるトナー粒子の投影像を示す説明図である。
【符号の説明】
１０ 感光体
１１ 帯電装置
１２ 露光装置
１３ 現像装置
１４ 転写装置
１５ 分離装置
１６ クリーニング装置
２０、２０Ａ、２０Ｂ 定着装置
２１、４１ 加熱ローラ
２５ 加圧ローラ
２２、２６ 芯金
２３、２８、４６３ 離型層
２７、４６２ 弾性層
３０ 押圧バネ
３１、４１Ａ 加熱源
３２ 温度検出手段
３３ 元巻きローラ
３４ 巻き取りローラ
３５ ウェブ
３６ バックアップローラ
３７ クリーニング機構
４２ 温度検知手段
４３、５２ クリーニングローラ
４５ 上加圧ローラ
４５１ 弾性部材
４６ 下加圧ローラ
４６１ 熱伝導性基体
４７ スプリング
５０ 加熱定着ベルト
５１ オイル塗布ローラ
Ｎ 定着ニップ部
Ｐ 記録材
ｔ 未定着トナー像[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus using, for example, an electrophotographic system.
[0002]
[Prior art]
Currently, in image forming apparatuses such as copying machines, printers, and facsimiles, a contact heating method such as a heat roller method or a heat fixing belt method is used as a fixing device for fixing an unfixed toner image on a recording material such as transfer paper. Things are widely used.
[0003]
For example, a heat roller type fixing device has a heating roller provided with a heating source such as a halogen heater lamp inside, and a pressure arranged so as to form a fixing nip portion (fixing region) by being pressed against the heating roller. And a fixing nip portion that heats and fixes an unfixed toner image formed on the recording material.
[0004]
When the fixing process is performed by such a contact heating method using a heating rotator such as a heating roller, the toner has sufficient releasability with respect to the heating rotator and has necessary offset resistance, and heating. It is required that the recording material is prevented from being wound around the rotating body (hereinafter simply referred to as “winding preventing property”).
[0005]
Conventionally, by setting the surface roughness of the heating rotator (heating roller or the like), for example, the center line average roughness (Ra) or the ten-point average roughness (Rz) to a predetermined value or less, the surface roughness of the rotator is reduced. In order to prevent the occurrence of the offset phenomenon due to the problem.
[0006]
However, it is difficult to reliably prevent the occurrence of the offset phenomenon simply by setting the surface roughness of the heating rotator to a predetermined value or less, and eventually, a high-quality image cannot be stably formed. There is a problem.
[0007]
On the other hand, a small diameter toner that can faithfully reproduce a latent image has attracted attention today, where a digital exposure method using a laser beam, LED, or the like has become mainstream. In general, the smaller the toner particle diameter, the lower the adhesive force with the recording paper due to melting during fixing, so that there is a problem that the non-offset region, that is, the practical fixing temperature range becomes narrow.
[0008]
[Problems to be solved by the invention]
The present invention has been made based on the circumstances as described above, and an object thereof is an image forming apparatus that is excellent in offset resistance and anti-winding characteristics, and can stably form high-quality images. An object is to provide an image forming method.
[0009]
[Means for Solving the Problems]
As a result of intensive studies by the present inventors, the surface roughness of the rotating body in contact with the surface on which the unfixed toner image of the recording material is formed is specified in relation to the number average particle diameter of the toner particles used. By using toner particles having a specific shape factor and the like obtained by salting out / fusing resin particles containing a release agent in a binder resin as a toner while satisfying the relationship, The inventors have found that the fixing characteristics can be stably obtained, and have completed the present invention. That is, the object of the present invention is achieved by the following configuration.
[0010]
1. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fusion-bonding resin particles containing a release agent in a binder resin and colorant particles. An image forming apparatus comprising toner particles having the obtained colored particles as a basic component, a variation coefficient of a shape factor of 16% or less, and a number variation coefficient in a number particle size distribution of 27% or less.
[0011]
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9
2. 2. The image forming apparatus as described in 1 above, wherein the proportion of toner particles having a shape factor in the range of 1.0 to 1.6 is 65% by number or more.
[0012]
3. 2. The image forming apparatus as described in 1 above, wherein the proportion of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more.
[0013]
4). 4. The image forming apparatus according to any one of items 1 to 3, wherein the ratio of toner particles having no corners is 50% by number or more.
[0014]
5. 5. The image forming apparatus as described in any one of 1 to 4 above, wherein the toner particles have a number average particle diameter of 3 to 8 μm.
[0015]
6). When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to any one of 1 to 5 above.
[0016]
7. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fusion-bonding resin particles containing a release agent in a binder resin and colorant particles. An image forming apparatus comprising toner particles having the obtained colored particles as a basic component, a proportion of toner particles having no corners of 50% by number or more, and a number variation coefficient in a number particle size distribution of 27% or less.
[0017]
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9
8). 8. The image forming apparatus as described in 7 above, wherein the proportion of toner particles having a shape factor in the range of 1.0 to 1.6 is 65% by number or more.
[0018]
9. 8. The image forming apparatus as described in 7 above, wherein the proportion of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more.
[0019]
10. 10. The image forming apparatus as described in any one of 7 to 9, wherein the toner particles have a number average particle diameter of 3 to 8 μm.
[0020]
11. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to any one of 7 to 10 above.
[0021]
12 Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fusion-bonding resin particles containing a release agent in a binder resin and colorant particles. The obtained colored particles are used as a basic component, and the ratio of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more, and the variation coefficient of the shape factor is 16% or less. An image forming apparatus.
[0022]
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9
13. 13. The image forming apparatus as described in 12 above, wherein the ratio of toner particles having no corners is 50% by number or more.
[0023]
14 14. The image forming apparatus as described in 12 or 13 above, wherein the toner particles have a number average particle diameter of 3 to 8 μm.
[0024]
15. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to any one of 12 to 14 above.
[0025]
16. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fuseting resin particles containing a crystalline polyester in a binder resin and colorant particles. An image forming apparatus comprising toner particles having the obtained colored particles as a basic component, a variation coefficient of a shape factor of 16% or less, and a number variation coefficient in a number particle size distribution of 27% or less.
[0026]
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9
17. 17. The image forming apparatus as described in 16 above, wherein the proportion of toner particles having a shape factor in the range of 1.0 to 1.6 is 65% by number or more.
[0027]
18. 17. The image forming apparatus as described in 16 above, wherein the proportion of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more.
[0028]
19. 19. The image forming apparatus as described in any one of 16 to 18, wherein the ratio of toner particles having no corners is 50% by number or more.
[0029]
20. 20. The image forming apparatus as described in any one of 16 to 19, wherein the toner particles have a number average particle diameter of 3 to 8 [mu] m.
[0030]
21. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to any one of 16 to 20.
[0031]
22. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fuseting resin particles containing a crystalline polyester in a binder resin and colorant particles. An image forming apparatus comprising toner particles having the obtained colored particles as a basic component, a proportion of toner particles having no corners of 50% by number or more, and a number variation coefficient in a number particle size distribution of 27% or less.
[0032]
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9
23. 23. The image forming apparatus as described in 22 above, wherein the proportion of toner particles having a shape factor in the range of 1.0 to 1.6 is 65% by number or more.
[0033]
24. 23. The image forming apparatus as described in 22 above, wherein the proportion of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more.
[0034]
25. 25. The image forming apparatus as described in any one of 22 to 24, wherein the toner particles have a number average particle diameter of 3 to 8 [mu] m.
[0035]
26. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to any one of 22 to 25.
[0036]
27. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fuseting resin particles containing a crystalline polyester in a binder resin and colorant particles. The obtained colored particles are used as a basic component, and the ratio of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more, and the variation coefficient of the shape factor is 16% or less.
An image forming apparatus.
[0037]
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9
28. 28. The image forming apparatus as described in 27 above, wherein the ratio of toner particles having no corners is 50% by number or more.
[0038]
29. 29. The image forming apparatus as described in 27 or 28, wherein the toner particles have a number average particle diameter of 3 to 8 μm.
[0039]
30. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to any one of 27 to 29.
[0040]
31. 31. An image forming method using the image forming apparatus according to any one of 1 to 30 above.
[0041]
In the present invention, “surface roughness Sm” defines an average interval of unevenness according to JIS B 0601. Specifically, for example, in the roughness curve r having unevenness as shown in FIG. A portion of the reference length L is extracted from the roughness curve r in the direction of the average line m, and the sum of the lengths (Sm1 to Smn) of the average line m corresponding to one peak and one adjacent valley in the extracted portion. The arithmetic mean value of the intervals between the many irregularities is expressed in units of micrometers [μm].
[0042]
In the present invention, “salting out / fusion” means that salting out (aggregation of fine particles) and fusion (disappearance of the interface between fine particles) proceed simultaneously, or salting out and fusion are performed simultaneously. The act of proceeding. In order to perform salting out and fusion at the same time, it is necessary to agglomerate fine particles (resin particles, colorant particles) under a temperature condition equal to or higher than the glass transition temperature (Tg) of the resin constituting the resin particles.
[0043]
In the present invention, “colored particles obtained by salting-out / fusion” are used as basic components. Colored particles obtained by salting-out / fusion can be used as toners as they are. This means that the toner can be constituted by adding inorganic particles, organic particles, or other external additives.
[0044]
In the image forming apparatus of the present invention, the rotating body in the heat fixing device can be constituted by a roller or an endless belt.
[0045]
According to the present invention, the surface roughness Sm of the rotating body in contact with the surface on which the unfixed toner image of the recording material is formed is set in relation to the number average particle diameter of the toner particles used, and the toner By using the specific toner as described above, the fixing process can be executed in a state in which the rotating body and the recording material (unfixed toner image) are in an optimal contact state, and accordingly, the rotation processing is performed. It is possible to reliably prevent the recording material from being wound around the body and the offset phenomenon, and a stable fixing characteristic can be obtained. That is, fixing performance is remarkably improved by using toner particles having a uniform shape distribution and particle size distribution and finely dispersed release agent or crystalline polyester, and setting the surface roughness Sm of the rotating member of the fixing member within a specific range. To improve.
[0046]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below.
<Image forming device>
FIG. 2 is an explanatory diagram showing an outline of a configuration in an example of the image forming apparatus of the present invention.
[0047]
The image forming apparatus includes a drum-shaped photoconductor 10 that is a latent image carrier that is driven to rotate, a charging device 11 that uniformly charges the surface of the photoconductor 10, and a photosensitive that is charged by the charging device 11. An exposure device 12 that exposes the surface of the body 10 to form an electrostatic latent image, and a developing device 13 that visualizes the electrostatic latent image formed by the exposure device 12 using a developer containing toner. A transfer device 14 that transfers a toner image formed on the photoconductor 10 to a recording material P such as transfer paper in a transfer region; a separation device 15 that separates the recording material P that is in close contact with the photoconductor 10; And a fixing device 20 that thermally fixes the unfixed toner image t transferred onto the recording material P. In FIG. 2, reference numeral 16 denotes a cleaning device that removes toner on the photoconductor 10 that has passed through the transfer region.
[0048]
The fixing device 20 includes two rotating bodies that are pressed against each other to form a fixing nip portion. A heating source is provided in at least one of the rotating bodies, and the fixing device 20 is formed on the recording material P in the fixing nip portion. For fixing a non-transferred toner image t, for example, a heat roller type fixing device in which a rotating body is constituted by a roller, or a heat fixing belt type fixing device in which at least one rotating body is constituted by an endless belt. Can be used.
[0049]
FIG. 3 is an explanatory diagram showing an outline of the configuration of an example of a heat roller type fixing device. The fixing device 20A includes a heating roller 21 serving as a first rotating member disposed in contact with a surface of the recording material P on which an unfixed toner image is carried (the upper surface of the recording material P in FIG. 3). The pressure roller 25 as a second rotating body is provided so as to form a fixing nip portion (fixing region) N by being pressed against the heating roller 21 by a pressing spring 30.
[0050]
In the heating roller 21, for example, a halogen heater lamp is provided as the heating source 31, and the temperature detection means 32 is positioned downstream of the fixing nip portion N in the moving direction (clockwise) of the heating roller 21. Is provided close to the surface of the heating roller 21.
[0051]
The heating roller 21 includes a cylindrical cored bar 22 extending in the width direction (perpendicular to the paper surface) of the recording material P to be conveyed, and a separation made of, for example, fluororesin formed on the outer peripheral surface of the cored bar 22. And a mold layer 23.
[0052]
Although it does not specifically limit as a material which comprises the metal core 22, Metals, such as aluminum, iron, copper, or those alloys can be mentioned.
[0053]
Examples of the fluororesin constituting the release layer 23 include PTFE (polytetrafluoroethylene) and PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin).
[0054]
The thickness of the release layer 23 is preferably 10 to 100 μm, for example, and more preferably 15 to 30 μm.
[0055]
The pressure roller 25 includes a metal core 26 made of metal, an elastic layer 27 formed on the surface of the metal core 26, and a release layer 28 formed on the surface of the elastic layer 27.
[0056]
The metal constituting the metal core 26 is not particularly limited, and examples thereof include metals such as iron, aluminum, and copper, or alloys thereof.
[0057]
The elastic body constituting the elastic layer 27 is not particularly limited, and examples thereof include various soft rubbers such as urethane rubber and silicone rubber, and sponge rubber.
[0058]
The thickness of the elastic layer 27 is preferably 3 to 10 mm, for example, and more preferably 5 to 8 mm.
[0059]
The release layer 28 is made of, for example, a fluororesin, and can be formed of a tube made of, for example, a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin (PFA).
[0060]
The thickness of the release layer 28 is preferably 20 to 100 μm, for example, and more preferably 30 to 70 μm.
[0061]
The fixing device 20A used in the present invention may be provided with a cleaning mechanism for cleaning the toner on the heating roller 21 as necessary. In this case, a cleaning method can be used by supplying silicone oil to the heating roller 21 by a pad, roller, web, etc. impregnated with silicone oil. In the example shown, the silicone oil is A cleaning mechanism 37 for supplying the web 35 stretched by the roller 33 and the take-up roller 34 is provided. In FIG. 3, reference numeral 36 denotes a backup roller that brings the web 35 into contact with the heating roller 21.
[0062]
FIG. 4 is an explanatory diagram showing an outline of a configuration in an example of a heat fixing belt type fixing device. The fixing device 20B is attached by an endless heat fixing belt 50 as a first rotating body, which is stretched around the heating roller 41 and the upper pressure roller 45 so as to be circulated, and a spring 47 made of, for example, a coil spring. And a lower pressure roller 46 as a second rotating body that is pressed against the heat fixing belt 50 by the upper pressure roller 45 to form a fixing nip portion N. In FIG. 4, reference numeral 42 denotes a temperature detection means for detecting the temperature of the heating roller 41, 43 denotes a cleaning roller for removing the toner adhering to the heat fixing belt 50, and t denotes an unfixed image carried on the recording material P. It is a toner image.
[0063]
The heating roller 41 is made of, for example, Teflon (R), and a heating source 41A made of, for example, a halogen lamp is provided inside.
[0064]
The entire upper pressure roller 45 is constituted by an elastic member 451 having a low hardness, for example. Here, the elastic member 451 has, for example, an Asker C hardness of 50 ° or less, and specific examples thereof include silicone rubber and silicone sponge rubber.
[0065]
The lower pressure roller 46 includes, for example, a heat conductive base 461 made of aluminum, an elastic layer 462 formed on the surface of the heat conductive base 461, and a release layer 463 formed on the surface of the elastic layer 462. It is comprised by.
[0066]
The elastic body constituting the elastic layer 462 is not particularly limited, and examples thereof include various soft rubbers such as urethane rubber and silicone rubber, and sponge rubber.
[0067]
The thickness of the elastic layer 462 is preferably, for example, 0.5 to 10 mm, and more preferably 2 to 5 mm.
[0068]
The release layer 463 is made of, for example, a fluororesin, and can be composed of a tube made of, for example, a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin (PFA).
[0069]
The thickness of the release layer 463 is preferably 20 to 100 μm, for example, and more preferably 30 to 70 μm.
[0070]
The heat fixing belt 50 is formed, for example, on an endless belt-shaped metal substrate obtained by electroforming nickel or an endless belt-shaped resin substrate made of a heat-resistant polyimide resin, and formed on the surface of the substrate. An elastic layer made of silicone rubber and a release layer made of, for example, a fluororesin, formed on the surface of the elastic layer.
[0071]
The thickness of the release layer is preferably, for example, 10 to 100 μm, and more preferably 15 to 30 μm.
[0072]
An oil application roller 51 that applies oil to the heat fixing belt 50 and a cleaning roller 52 that cleans the surface of the oil application roller 51 can be provided on the heat fixing belt 50. The cleaning roller 52 is not necessary depending on the releasability of the toner to be used and the material of the release layer on the surface of the heat fixing belt 50.
[0073]
In the above configuration, a rotating body (hereinafter also referred to as a “heating rotating body”) that is in contact with the surface of the recording material P on which the unfixed toner image t is carried (the upper surface of the recording material P in FIGS. 3 and 4). That is, as the heating roller 21 or the heat fixing belt 50, the surface roughness defined by the average interval Sm [μm] of the unevenness on the surface of the release layer is the number average particle size of the toner particles constituting the unfixed toner image t. When the diameter is D [μm], those satisfying the following formula are used.
[0074]
Formula: (280-20 × D) ≦ Sm ≦ 300 [μm]
When the surface roughness Sm of the heating rotator is smaller than (280-20 × D), it is difficult to prevent the offset phenomenon due to the surface roughness of the heating rotator, whereas the surface roughness When Sm exceeds 300 μm regardless of the number average particle diameter D of the toner particles used, the adhesiveness between the heating rotator and the recording material P is increased, and therefore the recording material P is in contact with the heating rotator. The peelability is lowered, and the recording material P is easily wound around the heating rotator.
[0075]
The surface roughness Sm of the heating rotator can be measured using, for example, “Sartronic 3+” (Taylor-Hobson). However, the measurement conditions of the surface roughness Sm used in the above formula are a standard length of 0.8 mm and an evaluation length of 4 mm.
<toner>
The toner used in the present invention is composed of toner particles having a specific particle size distribution and shape distribution, which will be described later, and is produced by salting out / fusing the toner particles (colored particles) together with a release agent or crystalline polyester. Therefore, the release agent and the crystalline polyester are well dispersed in the toner particles (colored particles). Further, as in the dissolution step described later, the release agent and the crystalline polyester are dissolved and dispersed in the polymerizable monomer and then salted out simultaneously with the generation of the toner particles (colored particles). A mold release agent and a crystalline polyester can be dispersed in a size of submicron from the molecular level. By combining such toner composed of toner particles with a rotating member of a fixing member having a specific surface roughness, the fixing performance is remarkably improved.
[0076]
The toner used in the present invention has a number average particle diameter (D) of toner particles constituting the toner of 2 to 9 μm, preferably 3.5 to 6.5 μm, more preferably 4 to 6 μm. It is said. The number average particle diameter of the toner particles can be controlled by the concentration of the flocculant (salting-out agent), the amount of organic solvent added, the fusing time, or the polymer composition in the production method described in detail later.
[0077]
When the number average particle size is 2 to 9 μm, toner particles that have high adhesion force that fly and adhere to the heating rotator to generate offset in the fixing process are reduced, and transfer efficiency is increased, resulting in halftone. The image quality of the fine lines, dots, etc. is improved.
[0078]
The toner [A] of the present invention is composed of toner particles having a shape coefficient variation coefficient of 16% or less and a number variation coefficient in the number particle size distribution of 27% or less.
[0079]
The toner [B] of the present invention is composed of toner particles in which the proportion of toner particles without corners is 50% by number or more and the number variation coefficient in the number particle size distribution is 27% or less.
[0080]
The toner [C] of the present invention is composed of toner particles in which the proportion of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more and the variation coefficient of the shape factor is 16% or less. Is done.
<Toner particle shape factor>
The “shape factor” of the toner particles of the present invention is represented by the following formula and indicates the degree of roundness of the toner particles.
Shape factor = ((maximum diameter / 2)²× π) / projection area
Here, the maximum diameter refers to the width of a particle that maximizes the interval between the parallel lines when the projected image of the toner particles on the plane is sandwiched between two parallel lines. The projected area refers to the area of the projected image of the toner particles on the plane.
[0081]
In the present invention, this shape factor is obtained by taking a photograph in which the toner particles are magnified 2000 times with a scanning electron microscope, and then using “SCANNING IMAGE ANALYZER” (manufactured by JEOL Ltd.) based on this photograph. It was measured by performing analysis. At this time, the shape factor of the present invention was measured by the above formula using 100 toner particles.
[0082]
In the toner [A] and toner [B] of the present invention, the proportion of toner particles having this shape factor in the range of 1.0 to 1.6 is preferably 65% by number or more, more preferably 70%. Number% or more. More preferably, the ratio of the toner particles having the shape factor in the range of 1.2 to 1.6 is 65% by number or more, and more preferably 70% by number or more.
[0083]
When the ratio of the toner particles having the shape factor in the range of 1.0 to 1.6 is 65% by number or more, the density of toner particles in the toner layer transferred to the transfer material is increased, and the fixing property is improved. The offset is less likely to occur. In addition, the toner particles are less likely to be crushed, the contamination of the charging member is reduced, and the chargeability of the toner is stabilized.
[0084]
In the toner [C] of the present invention, the proportion of toner particles having a shape factor in the range of 1.2 to 1.6 needs to be 65% by number or more, preferably 70% by number or more. is there.
[0085]
As a method for controlling the shape factor, the structure is adjusted by the temperature, time, and stirring strength when the resin particles containing the release agent and / or the crystalline polyester and the colorant particles are salted out / fused. be able to.
<Variation coefficient of toner shape factor>
The “shape coefficient variation coefficient” of the toner of the present invention is calculated from the following equation.
[0086]
Coefficient of variation = [S₁/ K] × 100 (%)
[Where S₁Indicates the standard deviation of the shape factor of 100 toner particles, and K indicates the average value of the shape factor. ]
In the toner [A] and toner [C] of the present invention, the coefficient of variation of the shape factor of the toner particles is 16% or less, preferably 14% or less. When the variation coefficient of the shape factor of the toner particles is 16% or less, voids in the transferred toner layer (powder layer) are reduced, fixing property is improved, and offset is less likely to occur. In addition, the charge amount distribution becomes sharp and the image quality is improved.
[0087]
In order to uniformly control the shape factor of the toner particles and the coefficient of variation of the shape factor without variation in lots, resin particles (polymer particles) containing a release agent and / or crystalline polyester are fused. In the step of controlling the shape, a method of determining an appropriate process end time while monitoring the characteristics of the toner particles (colored particles) being formed is preferable.
[0088]
Monitoring means that a measuring device is incorporated in-line, and process conditions are controlled based on the measurement result. In other words, the shape of the toner particles (colored particles) can be measured while incorporating the measurement of the shape etc. in-line, and performing sampling in the fusing step when the resin particles are salted out / fused with the colorant particles in an aqueous medium. The particle size is measured and the reaction is stopped when the desired shape is achieved.
[0089]
Although it does not specifically limit as a monitoring method, The flow type particle image analyzer FPIA-2000 (made by Toa Medical Electronics Co., Ltd.) can be used. This apparatus is suitable because the shape can be monitored by performing image processing in real time while passing the sample liquid. That is, a pump or the like is used from the reaction field and is constantly monitored to measure the shape and the like, and the reaction is stopped when the desired shape is obtained.
<Toner particle number variation coefficient>
The number particle size distribution and the number variation coefficient of the toner of the present invention are measured by a Coulter Counter TA- or Coulter Multisizer (manufactured by Coulter Inc.). In the present invention, a Coulter Multisizer is used, and an interface (manufactured by Nikkaki Co., Ltd.) that outputs a particle size distribution and a personal computer are connected. The aperture used in the Coulter Multisizer was 100 μm, and the volume and number of toners of 2 μm or more were measured to calculate the particle size distribution and average particle size. The number particle size distribution represents the relative frequency of the toner particles with respect to the particle size, and the number average particle size represents the median diameter in the number particle size distribution. The “number variation coefficient in the number particle size distribution” of the toner is calculated from the following equation.
[0090]
Number variation coefficient = [S₂/ D_n] X 100 (%)
[Where S₂Indicates the standard deviation in the number particle size distribution, D_nIndicates the number average particle diameter (μm). ]
The number variation coefficient of the toner [A] and toner [B] of the present invention is 27% or less, preferably 25% or less. When the number variation coefficient is 27% or less, voids in the transferred toner layer (powder layer) are reduced, fixing properties are improved, and offset is less likely to occur. In addition, the charge amount distribution becomes sharp, the transfer efficiency is increased, and the image quality is improved.
[0091]
The method for controlling the number variation coefficient in the toner of the present invention is not particularly limited. For example, a method of classifying toner particles by wind force can be used, but classification in a liquid is effective for reducing the number variation coefficient. As a method of classifying in this liquid, there is a method of separating and collecting toner particles according to a difference in sedimentation speed caused by a difference in toner particle diameter by using a centrifuge and controlling the rotation speed.
<Percentage of toner particles without corners>
In the toner particles constituting the toner [B] of the present invention, the ratio of toner particles having no corners is required to be 50% by number or more, and this ratio is preferably 70% by number or more.
[0092]
In the toner particles constituting the toner [A] and toner [C] of the present invention, the proportion of toner particles having no corners is preferably 50 number% or more, more preferably 70 number% or more.
[0093]
When the ratio of the toner particles having no corners is 50% by number or more, voids in the transferred toner layer (powder layer) are reduced, fixing property is improved, and offset is hardly generated. In addition, toner particles that easily wear and break and toner particles having a portion where charges are concentrated are reduced, the charge amount distribution becomes sharp, the chargeability is stable, and good image quality can be formed over a long period of time.
[0094]
Here, the “toner particles having no corners” means toner particles having substantially no protrusions that concentrate electric charges or protrusions that easily wear due to stress. Specifically, the following toner particles are used. Is called toner particles having no corners. That is, as shown in FIG. 5A, when the major axis of the toner particles T is L, a circle C having a radius (L / 10) is in contact with the peripheral line of the toner particles T at one point. A case where the circle C does not substantially protrude outside the toner T when the inner side is rolled is referred to as “toner particles having no corners”. “A case where the protrusion does not substantially protrude” refers to a case where the protrusion having the protruding circle is one or less. The “major diameter of toner particles” refers to the width of a particle that maximizes the interval between the parallel lines when the projected image of the toner particles on a plane is sandwiched between two parallel lines. 5B and 5C show projection images of toner particles having corners, respectively.
[0095]
The ratio of toner particles having no corners was measured as follows. First, an enlarged photograph of the toner particles is taken with a scanning electron microscope, and further enlarged to obtain a 15,000 times photographic image. The photographic image is then measured for the presence or absence of the corners. This measurement was performed on 100 toner particles.
[0096]
In addition, the surface of the fused particles has a lot of irregularities and the surface is not smooth at the fusion stopping stage when the resin particles are salted out / fused, but the temperature in the shape control process, the number of rotations of the stirring blade, and the stirring By making appropriate conditions such as time, a toner having no corners can be obtained. These conditions vary depending on the physical properties of the resin particles. For example, by setting the rotational speed to be higher than the glass transition temperature of the resin particles, the toner can be formed with a smooth surface and no corners.
<Toner particle size>
The toner of the present invention preferably has a number average particle diameter of 3 to 8 μm. When the toner particles are formed by a polymerization method, this particle size is determined in the toner production method described in detail later, in the concentration of the aggregating agent, the amount of organic solvent added, or the fusing time, and further the composition of the polymer itself. Can be controlled by.
[0097]
When the number average particle diameter is 3 to 8 μm, toner particles having high adhesion force that fly and adhere to the heating member and generate offset in the fixing process are reduced, and transfer efficiency is increased and halftone The image quality is improved, and the image quality of fine lines and dots is improved.
[0098]
As the toner of the present invention, when the particle size of the toner particle is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the number-based particle size distribution is divided into a plurality of classes at intervals of 0.23. In the histogram shown, the sum (M) of the relative frequency (m1) of the toner particles included in the most frequent class and the relative frequency (m2) of the toner particles included in the next most frequent class after the most frequent class is 70. % Of the toner is preferable.
[0099]
When the sum (M) of the relative frequency (m1) and the relative frequency (m2) is 70% or more, the dispersion of the particle size distribution of the toner particles becomes narrow. Therefore, selective development can be performed by using the toner in the image forming process. Can be reliably suppressed.
[0100]
In the present invention, the histogram showing the particle size distribution based on the number is a natural logarithm lnD (D: particle size of individual toner particles) having a plurality of classes (0 to 0.23: 0.23) at intervals of 0.23. 0.46: 0.46-0.69: 0.69-0.92: 0.92-1.15: 1.15-1.38: 1.38-1.61: 1.61-1. 84: 1.84 to 2.07: 2.07 to 2.30: 2.30 to 2.53: 2.53 to 2.76, and so on). This histogram was created by transferring the particle size data of the sample measured by the Coulter Multisizer to the computer via the I / O unit according to the following conditions and using the particle size distribution analysis program in the computer. is there.
〔Measurement condition〕
(1) Aperture: 100 μm
(2) Sample preparation method: Electrolyte [ISOTON R-11 (manufactured by Coulter Scientific Japan)] 50-100 ml, an appropriate amount of a surfactant (neutral detergent) was added and stirred, and a measurement sample 10-20 mg was added thereto. Add This system is prepared by dispersing for 1 minute with an ultrasonic disperser.
<Release agent>
The toner particles according to claims 1 to 15 are associative colored particles (toner particles) obtained by salting out / fusing resin particles containing a release agent in a binder resin and colorant particles. ).
[0101]
The release agent constituting the toner of the present invention is not particularly limited, but is composed of a crystalline ester compound represented by the following general formula (1) (hereinafter referred to as “specific ester compound”). It is preferable.
[0102]
General formula (1): R¹(OCO-R²)_n
(Wherein R¹And R²Each represents a hydrocarbon group having 1 to 40 carbon atoms which may have a substituent, and n is an integer of 1 to 4. )
<Specific ester compounds>
In general formula (1) showing a specific ester compound, R¹And R²Each represents a hydrocarbon group which may have a substituent.
[0103]
Hydrocarbon group R¹The number of carbon atoms is 1 to 40, preferably 1 to 20, and more preferably 2 to 5.
[0104]
Hydrocarbon group R²The number of carbon atoms is from 1 to 40, preferably from 16 to 30, and more preferably from 18 to 26.
[0105]
In the general formula (1), n is an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably 4.
[0106]
The specific ester compound can be suitably synthesized by a dehydration condensation reaction between an alcohol and a carboxylic acid.
[0107]
Specific examples of the specific ester compound include compounds represented by the following formulas 1) to 22).
[0108]
[Chemical 1]

[0109]
[Chemical formula 2]

[0110]
<Ratio of release agent>
The content of the release agent in the toner of the present invention is usually 1 to 30% by mass, preferably 2 to 20% by mass, and more preferably 3 to 15% by mass.
<Crystalline polyester>
The toner particles according to claims 16 to 30 are associative colored particles (toner particles) obtained by salting out / fusion of resin particles containing crystalline polyester in a binder resin and colorant particles. ).
[0111]
Here, the crystalline polyester contained in the resin particles is a compound that imparts good fixability (adhesiveness to the image forming support) to the toner obtained by fusing the resin particles.
[Physical properties of crystalline polyester]
The melting point of the crystalline polyester is preferably 50 to 130 ° C, more preferably 60 to 120 ° C.
[0112]
According to the crystalline polyester having a melting point in the range of 50 to 130 ° C., it is possible to lower the overall melt viscosity of the obtained toner and to improve the adhesion to paper or the like. In addition, even when the crystalline polyester is present, the high-temperature elastic modulus is maintained in a preferable range, so that excellent offset resistance is exhibited. When the melting point of the crystalline polyester is less than 50 ° C., the fixability itself is improved, but the storability is lowered, causing a problem in practical use. On the other hand, when the melting point exceeds 130 ° C., the melting start temperature becomes high, so that the contribution to the improvement of the fixability is low and the effect of improving the fixability is reduced.
[0113]
Here, melting | fusing point of crystalline polyester means the value measured with the differential calorimeter (DSC). Specifically, the temperature showing the maximum peak of the endothermic peak measured when the temperature is raised from 0 ° C. to 200 ° C. under the condition of 10 ° C./min (first temperature raising process) is defined as the melting point. And this melting | fusing point corresponds with the "endothermic peak (P1) in the 1st temperature rising process by DSC" mentioned later.
[0114]
As a specific measuring device of the melting point, DSC-7 manufactured by PerkinElmer, Inc. can be exemplified.
[0115]
The number average molecular weight of the crystalline polyester is preferably 1,500 to 15,000, more preferably 2,000 to 10,000.
[0116]
According to the crystalline polyester having a number average molecular weight in the range of 1,500 to 15,000, the resulting toner is melted with a binder resin (amorphous polymer) for exhibiting a decrease in the overall melt viscosity. The compatibility in the state is improved, and the fixability on the lower temperature side is improved. When the number average molecular weight is less than 1,500, the melt viscosity of the crystalline polyester becomes excessively low, and on the contrary, the compatible state tends to be non-uniform, and it becomes difficult to improve the fixability. On the other hand, when the number average molecular weight exceeds 15,000, it takes a long time to melt the crystalline polyester. Even in this case, the compatibility state becomes non-uniform, so that the effect of improving the fixability is lowered.
[0117]
Here, the number average molecular weight of the crystalline polyester refers to a value obtained from the molecular weight measured according to the following conditions.
(conditions)
-Model used: "LC-6A" (manufactured by Shimadzu Corporation)
・ Column: "Ultra Style Gel Plus"
・ Analysis temperature: 60 ° C
Solvent: m-cresol / chlorobenzene = 3/1 (volume ratio)
-Calibration curve: Standard polystyrene calibration curve
The melt viscosity (melting point + melt viscosity at 20 ° C.) of the crystalline polyester is preferably 100 dPa · s or less, more preferably 60 dPa · s or less.
[0118]
According to the crystalline polyester having a melt viscosity of 100 dPa · s or less, the entire melt viscosity including the binder resin can be lowered in the obtained toner, and the fixability is improved. When this melt viscosity exceeds 100 dPa · s, the overall melt viscosity becomes high, so that the effect of improving the fixability becomes low.
[0119]
Here, the melt viscosity of the crystalline polyester (melting point + melting viscosity at 20 ° C.) refers to a value measured with a cone plate viscometer.
[0120]
The peak molecular weight of the crystalline polyester by GPC is 6,000 to 50,000.
[0121]
It is preferable that the crystalline polyester has an endothermic peak (P1) in the first temperature rising process by DSC at 50 to 130 ° C, particularly 60 to 120 ° C.
[0122]
Moreover, it is preferable that crystalline polyester has the exothermic peak (P2) in the 1st cooling process by DSC in 30-110 degreeC, especially 40-120 degreeC.
[0123]
Here, the relationship of P1 ≧ P2 is established between the endothermic peak (P1) and the exothermic peak (P2). The temperature difference (P1-P2) is not particularly limited, but is preferably 50 ° C. or less.
[0124]
By including the crystalline polyester having the thermal characteristics as described above, an excellent offset prevention effect (wide fixing temperature range) and an excellent fixing property (high fixing rate) can be exhibited.
[0125]
In order to exert the effect of the present invention, it is preferable that the binder resin and the crystalline polyester exist in an independent state. That is, the crystalline polyester dissolves sharply and works to dissolve the binder resin in the melted state. As a result, the melt viscosity of the entire toner can be lowered, and the fixability can be improved. . In addition, since they can exist independently of each other, it is possible to suppress a decrease in elastic modulus on the high temperature side, so that the offset resistance is not impaired.
[0126]
When the endothermic peak (P1) is less than 50 ° C., the melting temperature is low, so that the fixability is improved, but the offset resistance and the storage stability are lowered.
[0127]
Further, when the endothermic peak (P1) is in a range exceeding 130 ° C., the melting temperature is high, so that the melting temperature with the binder resin is high, and as a result, the fixability cannot be improved.
[0128]
When the exothermic peak (P2) indicating the recrystallization state exists below 30 ° C., it cannot be recrystallized unless it is cooled to a considerably low temperature, and such a substance has a low crystallinity. Therefore, it cannot be contributed to the improvement of the fixing property.
[0129]
If the exothermic peak (P2) is in a range exceeding 110 ° C., the recrystallization temperature is too high, the so-called melting temperature is also increased, and the low-temperature fixability is impaired.
[0130]
The endothermic peak (P1) and the exothermic peak (P2) are measured by a differential calorimeter (DSC). As the temperature raising / cooling condition, the temperature is allowed to stand at 0 ° C. for 1 minute, and then the temperature is raised to 200 ° C. under a condition of 10 ° C./min. Then, after leaving at 200 ° C. for 1 minute, the temperature is lowered under the condition of 10 ° C./min, and the temperature showing the maximum exothermic peak measured at that time is defined as P2. Specific examples of the measuring apparatus include DSC-7 manufactured by Perkin Elmer.
[Composition of crystalline polyester]
As the crystalline polyester, a polyester obtained by reacting an aliphatic diol and an aliphatic dicarboxylic acid (including an acid anhydride and an acid chloride) is preferable.
[0131]
Examples of the diol used to obtain the crystalline polyester include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, and 1,4-butenediol. , Neopentyl glycol, 1,5-pentane glycol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, bisphenol Z, hydrogenated bisphenol A and the like.
[0132]
Dicarboxylic acids used to obtain crystalline polyesters include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, citraconic acid , Itaconic acid, glutamic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, acid anhydrides or acid chlorides thereof Can be mentioned.
[0133]
Particularly preferred crystalline polyesters include polyesters obtained by reacting 1,4-cyclohexanedimethanol and adipic acid, polyesters obtained by reacting 1,6-hexanediol and sebacic acid, ethylene glycol and succinic acid. And polyester obtained by reacting ethylene glycol and sebacic acid, polyester obtained by reacting 1,4-butanediol and succinic acid, among these, Most preferred is a polyester obtained by reacting 1,4-cyclohexanedimethanol with adipic acid.
<Content ratio of crystalline polyester>
The content of the crystalline polyester in the toner of the present invention is usually 1 to 50% by mass, preferably 5 to 40% by mass, and more preferably 5 to 30% by mass.
<Resin Particles Containing Release Agent / Resin Particles Containing Crystalline Polyester>
In the present invention, “resin particles containing a release agent” means that a release agent is dissolved in a monomer for obtaining a binder resin, and the resulting monomer solution is dispersed in an aqueous medium. Can be obtained as latex particles.
[0134]
In addition, “resin particles containing crystalline polyester” is obtained by dissolving crystalline polyester in a monomer for obtaining a binder resin and dispersing the resulting monomer solution in an aqueous medium. By polymerizing, it can be obtained as latex particles.
[0135]
The resin particles preferably have a weight average particle diameter of 10 to 2000 nm.
Examples of the polymerization method for obtaining resin particles containing a release agent and / or crystalline polyester in a binder resin include granulation polymerization methods such as an emulsion polymerization method, a suspension polymerization method, and a seed polymerization method. Can do.
[0136]
As a preferable polymerization method for obtaining resin particles containing a release agent and / or crystalline polyester, a release agent and / or in an aqueous medium in which a surfactant having a concentration equal to or lower than the critical micelle concentration is dissolved. A monomer solution obtained by dissolving crystalline polyester in a monomer is formed into oil droplets (10 to 1000 nm) using mechanical energy to prepare a dispersion, and the resulting dispersion is dissolved in water. And a method of radical polymerization by adding a cationic polymerization initiator (hereinafter referred to as “mini-emulsion method” in this specification). Instead of adding a water-soluble polymerization initiator, or while adding the water-soluble polymerization initiator, an oil-soluble polymerization initiator may be added to the monomer solution.
[0137]
Here, the disperser for dispersing oil droplets by mechanical energy is not particularly limited, and a stirring device “CLEARMIX” equipped with a rotor that rotates at high speed (M Technique Co., Ltd.) Product), ultrasonic dispersers, mechanical homogenizers, Manton gorin, pressure homogenizers, and the like. The dispersed particle diameter is 10 to 1000 nm, preferably 30 to 300 nm.
<Binder resin>
The binder resin constituting the toner of the present invention comprises a high molecular weight component having a peak or shoulder in the region of 150,000 to 1,000,000 in the molecular weight distribution measured by GPC, and 1,000 to 20,000. A resin containing a low molecular weight component having a peak or shoulder in the region is preferable. Furthermore, it is preferable to contain an intermediate molecular weight component having a peak or shoulder in the region of 50,000 to 140,000. Thus, by using a high molecular weight component and a low molecular weight component in combination, it is possible to achieve both improvement in offset resistance and fixability (adhesiveness to an image forming support).
[0138]
Here, as a method for measuring the molecular weight of the resin by GPC, 1 ml of THF is added to 0.5 to 5.0 mg (specifically, 1 mg) of a measurement sample, and stirring is performed at room temperature using a magnetic stirrer or the like. Go and dissolve well. Subsequently, after processing with a membrane filter having a pore size of 0.45 to 0.50 μm, the solution is injected into GPC.
[0139]
As GPC measurement conditions, the column is stabilized at 40 ° C., THF is allowed to flow at a flow rate of 1 ml / min, and about 100 μl of a sample having a concentration of 1 mg / ml is injected for measurement. The column is preferably used in combination with a commercially available polystyrene gel column. For example, a combination of Shodex GPC KF-801, 802, 803, 804, 805, 806, and 807 manufactured by Showa Denko KK and TSKgel G1000H, G2000H, G3000H, G4000H, G6000H, G7000H, T7000 guard column manufactured by Tosoh Corporation Combinations can be mentioned. As a detector, a refractive index detector (IR detector) or a UV detector may be used. In the measurement of the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodisperse polystyrene standard particles. About 10 points may be used as polystyrene for preparing a calibration curve.
[0140]
Hereinafter, the constituent material of resin particles and the preparation method (polymerization method) will be described.
(Monomer)
As a polymerizable monomer used for obtaining resin particles, a radical polymerizable monomer is an essential constituent component, and a crosslinking agent can be used as necessary. Moreover, it is preferable to contain at least one radical polymerizable monomer having the following acidic group or radical polymerizable monomer having a basic group.
(1) Radical polymerizable monomer:
The radical polymerizable monomer is not particularly limited, and a conventionally known radical polymerizable monomer can be used. Moreover, it can be used combining 1 type (s) or 2 or more types so that the required characteristic may be satisfy | filled.
[0141]
Specifically, aromatic vinyl monomers, (meth) acrylic acid ester monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers , Halogenated olefin monomers and the like can be used.
[0142]
Examples of the aromatic vinyl monomer include styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, p-methoxy styrene, p-phenyl styrene, p-chloro styrene, p-ethyl styrene, p. -N-butyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, 2, Examples thereof include styrene monomers such as 4-dimethylstyrene and 3,4-dichlorostyrene and derivatives thereof.
[0143]
Examples of (meth) acrylic acid ester monomers include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, and methacrylic acid. Examples include butyl, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and the like.
[0144]
Examples of vinyl ester monomers include vinyl acetate, vinyl propionate, and vinyl benzoate.
[0145]
Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like.
[0146]
Examples of the monoolefin monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene, 4-methyl-1-pentene and the like.
[0147]
Examples of the diolefin monomer include butadiene, isoprene, chloroprene and the like.
[0148]
Examples of the halogenated olefin monomer include vinyl chloride, vinylidene chloride, vinyl bromide and the like.
(2) Crosslinking agent:
As the crosslinking agent, a radical polymerizable crosslinking agent may be added in order to improve the properties of the toner. Examples of the radical polymerizable crosslinking agent include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate.
(3) Radical polymerizable monomer having an acidic group or a basic group:
Examples of the radical polymerizable monomer having an acidic group or the radical polymerizable monomer having a basic group include a carboxyl group-containing monomer, a sulfonic acid group-containing monomer, a primary amine, and a secondary group. Amine-based compounds such as amines, tertiary amines, and quaternary ammonium salts can be used.
[0149]
Examples of the radical polymerizable monomer having an acidic group include carboxylic acid group-containing monomers such as acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, maleic acid monobutyl ester, and maleic acid monoester. An octyl ester etc. are mentioned.
[0150]
Examples of the sulfonic acid group-containing monomer include styrene sulfonic acid, allyl sulfosuccinic acid, octyl allyl sulfosuccinate and the like.
[0151]
These may have a structure of an alkali metal salt such as sodium or potassium or an alkaline earth metal salt such as calcium.
[0152]
Examples of the radical polymerizable monomer having a basic group include amine compounds, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and quaternary ammonium salts of the above four compounds, 3-dimethylaminophenyl acrylate, 2-hydroxy-3-methacryloxypropyltrimethylammonium salt, acrylamide, N-butylacrylamide, N, N-dibutylacrylamide, piperidylacrylamide, methacrylamide, N-butylmethacrylamide, N-octadecylacrylamide Vinyl pyridine, vinyl pyrrolidone; vinyl N-methylpyridinium chloride, vinyl N-ethylpyridinium chloride, N, N-diallyl Examples thereof include methylammonium chloride and N, N-diallylethylammonium chloride.
[0153]
As the radical polymerizable monomer used in the present invention, a radical polymerizable monomer having an acidic group or a radical polymerizable monomer having a basic group is used in an amount of 0.1 to 15% by mass based on the whole monomer. The radical polymerizable crosslinking agent is preferably used in the range of 0.1 to 10% by mass with respect to the total radical polymerizable monomer, although it depends on its properties.
[Chain transfer agent]
For the purpose of adjusting the molecular weight of the resin particles, it is possible to use a commonly used chain transfer agent.
[0154]
The chain transfer agent is not particularly limited, and examples thereof include mercaptans such as octyl mercaptan, dodecyl mercaptan, tert-dodecyl mercaptan, n-octyl-3-mercaptopropionic acid ester, terpinolene, carbon tetrabromide and α-methylstyrene. Dimers etc. are used.
(Polymerization initiator)
The radical polymerization initiator used in the present invention can be appropriately used as long as it is water-soluble. For example, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4′-azobis-4-cyanovaleric acid and its salts, 2,2′-azobis (2-amidinopropane) salts, etc.), peroxides Compounds and the like.
[0155]
Furthermore, the radical polymerization initiator can be combined with a reducing agent as necessary to form a redox initiator. By using a redox initiator, the polymerization activity is increased, the polymerization temperature is lowered, and the polymerization time can be further shortened.
[0156]
The polymerization temperature may be any temperature as long as it is equal to or higher than the lowest radical generation temperature of the polymerization initiator, but for example, a range of 50 ° C. to 90 ° C. is used. However, it is possible to perform polymerization at room temperature or higher by using a polymerization initiator that starts at room temperature, for example, a combination of hydrogen peroxide and a reducing agent (ascorbic acid or the like).
[Surfactant]
In order to perform polymerization using the above-mentioned radical polymerizable monomer, it is necessary to perform oil droplet dispersion in an aqueous medium using a surfactant. Although it does not specifically limit as surfactant which can be used in this case, The following ionic surfactant can be mentioned as an example of a suitable thing.
[0157]
Examples of ionic surfactants include sulfonates (sodium dodecylbenzenesulfonate, sodium arylalkylpolyethersulfonate, 3,3-disulfonediphenylurea-4,4-diazo-bis-amino-8-naphthol-6 Sodium sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-6-sodium sulfonate, etc.), sulfuric acid Ester salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate) Beam, calcium oleate and the like).
[0158]
Nonionic surfactants can also be used. Specifically, polyethylene oxide, polypropylene oxide, combination of polypropylene oxide and polyethylene oxide, ester of polyethylene glycol and higher fatty acid, alkylphenol polyethylene oxide, ester of higher fatty acid and polyethylene glycol, ester of higher fatty acid and polypropylene oxide, sorbitan ester Etc. can be mentioned.
<Colorant>
Examples of the colorant constituting the toner of the present invention include inorganic pigments, organic pigments, and dyes.
[0159]
A conventionally well-known thing can be used as an inorganic pigment. Specific inorganic pigments are exemplified below.
[0160]
Examples of the black pigment include carbon black such as furnace black, channel black, acetylene black, thermal black, and lamp black, and magnetic powder such as magnetite and ferrite.
[0161]
These inorganic pigments can be used alone or in combination as required. Moreover, the addition amount of a pigment is 2-20 mass% with respect to a polymer, Preferably 3-15 mass% is selected.
[0162]
When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, it is preferable to add 20 to 60% by mass in the toner from the viewpoint of imparting predetermined magnetic properties.
[0163]
Conventionally known organic pigments and dyes can also be used. Specific organic pigments and dyes are exemplified below.
[0164]
Examples of pigments for magenta or red include C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. And CI Pigment Red 222.
[0165]
Examples of the orange or yellow pigment include C.I. I. Pigment orange 31, C.I. I. Pigment orange 43, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 185, C.I. I. Pigment yellow 155, C.I. I. And CI Pigment Yellow 156.
[0166]
Examples of pigments for green or cyan include C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 16, C.I. I. Pigment blue 60, C.I. I. And CI Pigment Green 7.
[0167]
As the dye, C.I. I. Solvent Red 1, 49, 52, 58, 63, 111, 122, C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93, 95 etc. can be used, and a mixture thereof can also be used.
[0168]
These organic pigments and dyes can be used alone or in combination as desired. Moreover, the addition amount of a pigment is 2-20 mass% with respect to a polymer, Preferably 3-15 mass% is selected.
[0169]
The colorant can also be used after surface modification. As the surface modifier, conventionally known ones can be used, and specifically, silane coupling agents, titanium coupling agents, aluminum coupling agents and the like can be preferably used.
<External additive>
In the toner of the present invention, a so-called external additive is added to the colored particles obtained by the salting-out / fusion described above for the purpose of improving fluidity, chargeability and cleaning properties. Can do. These external additives are not particularly limited, and various inorganic fine particles, organic fine particles and lubricants can be used.
[0170]
A conventionally well-known thing can be used as an inorganic fine particle. Specifically, silica, titanium, alumina fine particles and the like can be preferably used. These inorganic fine particles are preferably hydrophobic. Specifically, as silica fine particles, for example, commercially available products R-805, R-976, R-974, R-972, R-812, R-809 manufactured by Nippon Aerosil Co., Ltd., HVK-2150, H manufactured by Hoechst -200, commercially available products TS-720, TS-530, TS-610, H-5, MS-5 and the like manufactured by Cabot Corporation.
[0171]
Examples of the titanium fine particles include commercial products T-805 and T-604 manufactured by Nippon Aerosil Co., Ltd., commercial products MT-100S, MT-100B, MT-500BS, MT-600, MT-600SS, and JA- 1. Commercial products TA-300SI, TA-500, TAF-130, TAF-510, TAF-510T manufactured by Fuji Titanium Co., Ltd. Commercial products IT-S, IT-OA, IT-OB, IT- manufactured by Idemitsu Kosan Co., Ltd. OC etc. are mentioned.
[0172]
Examples of the alumina fine particles include commercial products RFY-C and C-604 manufactured by Nippon Aerosil Co., Ltd. and commercial products TTO-55 manufactured by Ishihara Sangyo Co., Ltd.
[0173]
As the organic fine particles, spherical organic fine particles having a number average primary particle diameter of about 10 to 2000 nm can be used. As this, a homopolymer such as styrene or methyl methacrylate or a copolymer thereof can be used.
[0174]
Examples of lubricants include, for example, zinc stearate, aluminum, copper, magnesium, calcium, etc., zinc oleate, manganese, iron, copper, magnesium, etc., zinc palmitate, copper, magnesium, calcium, etc. And salts of higher fatty acids such as zinc of linoleic acid, salts of calcium, etc., zinc of ricinoleic acid, salts of calcium, etc.
[0175]
The amount of these external additives added is preferably 0.1 to 5% by mass with respect to the toner.
The toner of the present invention contains associative colored particles obtained by salting out / fusing resin particles containing a release agent and / or crystalline polyester and colorant particles in an aqueous medium as a basic component. .
[0176]
As described above, by salting out / fusing the resin particles containing the release agent and / or crystalline polyester, a toner in which the release agent and / or crystalline polyester is finely dispersed can be obtained.
[0177]
The toner of the present invention has an irregular shape on the surface from the time of manufacture, and is an associative toner obtained by fusing resin particles and colorant particles in an aqueous medium. Therefore, the difference in shape and surface property between toner particles is extremely small, and as a result, the surface property tends to be uniform. For this reason, it is difficult to make a difference in the fixability between the toners, and the fixability can be kept good.
<Toner manufacturing process>
As an example of a method for producing the toner of the present invention,
(1) A dissolution step of preparing a monomer solution by dissolving a release agent and / or crystalline polyester in a monomer,
(2) A dispersion step of dispersing the obtained monomer solution in an aqueous medium,
(3) a polymerization step of preparing a dispersion (latex) of resin particles containing a release agent and / or crystalline polyester by polymerizing an aqueous dispersion of the resulting monomer solution;
(4) a salting-out / fusing step in which the resulting resin particles and the colorant particles are salted out / fused in an aqueous medium to obtain associated colored particles (toner particles);
(5) A filtration / washing step of filtering the associated colored particles obtained from an aqueous medium and washing away the surfactant from the associated colored particles.
(6) Consists of a drying step for the washed associated colored particles,
(7) An external additive addition step of adding an external additive to the association-colored particles subjected to the drying treatment may be included.
[Dissolution process]
The method for dissolving the release agent and / or crystalline polyester in the monomer is not particularly limited.
[0178]
The amount of the release agent dissolved in the monomer is such that the content of the release agent in the finally obtained toner is 1 to 30% by mass, preferably 2 to 20% by mass, more preferably 3 to 15% by mass. It is made an amount.
[0179]
The amount of crystalline polyester dissolved in the monomer is such that the content of the crystalline polyester in the finally obtained toner is 1 to 50% by mass, preferably 5 to 40% by mass, more preferably 5 to 30% by mass. It is made an amount.
[0180]
An oil-soluble polymerization initiator and other oil-soluble components can also be added to the monomer solution.
[Dispersing process]
The method of dispersing the monomer solution in the aqueous medium is not particularly limited, but a method of dispersing by mechanical energy is preferable, and in particular, a surfactant having a concentration equal to or lower than the critical micelle concentration is dissolved. It is preferable to disperse oil droplets of the monomer solution in the aqueous medium to be obtained (essential aspect in the miniemulsion method).
[0181]
Here, the disperser for dispersing oil droplets by mechanical energy is not particularly limited. For example, “CLEARMIX”, ultrasonic disperser, mechanical homogenizer, Manton Gorin and pressure homogenizer, etc. Can be mentioned. The dispersed particle diameter is 10 to 1000 nm, preferably 30 to 300 nm.
[Polymerization process]
In the polymerization step, a conventionally known polymerization method (granulation polymerization method such as emulsion polymerization method, suspension polymerization method, seed polymerization method, etc.) can be basically employed.
[0182]
An example of a preferred polymerization method is a mini-emulsion method, that is, a monomer solution is dispersed in oil droplets using mechanical energy in an aqueous medium in which a surfactant having a critical micelle concentration or less is dissolved. Examples of the method include radical polymerization by adding a water-soluble polymerization initiator to the resulting dispersion.
[Salting out / fusion process]
In the salting-out / fusion step, a dispersion of colorant particles is added to the dispersion of resin particles obtained by the polymerization step, and the resin particles and the colorant particles are salted out in an aqueous medium. By fusing, colored particles (toner particles) are obtained.
[0183]
In the salting-out / fusion step, internal additive particles such as a charge control agent can be fused together with the resin particles and the colorant particles.
[0184]
Further, in the salting-out / fusion process, resin particles not containing these can be fused together with the resin particles containing the release agent and / or crystalline polyester.
[0185]
Here, as a preferred embodiment, intermediate molecular weight resin particles (MP) containing a release agent and / or crystalline polyester, low molecular weight resin particles (LP), high molecular weight resin particles (HP), Examples thereof include a method of salting out / fusing colorant particles to obtain colored particles.
[0186]
By including the release agent and / or the crystalline polyester only in the intermediate molecular weight resin particles (MP), excellent offset resistance / fixing property due to the intermediate molecular weight resin particles (MP) is expressed, and high The offset resistance and anti-winding property imparted by the molecular weight resin particles (HP) and the suitable fixing property imparted by the low molecular weight resin particles (LP) are not impaired.
[0187]
The “aqueous medium” in the salting out / fusion step refers to a material in which the main component (50% by mass or more) is water. Examples of components other than water include organic solvents that dissolve in water, such as methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, and tetrahydrofuran. Among these, alcohol-based organic solvents such as methanol, ethanol, isopropanol, and butanol, which are organic solvents that do not dissolve the resin, are particularly preferable.
[0188]
The colorant particles used in the salting out / fusion process can be prepared by dispersing the colorant in an aqueous medium. The dispersion treatment of the colorant is performed in a state where the surfactant concentration is set to a critical micelle concentration (CMC) or more in water.
[0189]
The disperser used for the dispersion treatment of the colorant is not particularly limited, but preferably “CLEAMIX”, ultrasonic disperser, mechanical homogenizer, pressure disperser such as Manton Gorin and pressure homogenizer, sand grinder, Getzmann mill And medium type dispersers such as diamond fine mill. Moreover, as a surfactant used, the same thing as the above-mentioned surfactant can be mentioned.
[0190]
The colorant (particles) may be surface-modified. In the surface modification method of the colorant, the colorant is dispersed in a solvent, the surface modifier is added to the dispersion, and the system is reacted by raising the temperature. After completion of the reaction, the colorant is separated by filtration, washed and filtered with the same solvent, and dried to obtain a colorant (pigment) treated with the surface modifier.
[0191]
In the salting-out / fusion method, a salting-out agent composed of an alkali metal salt and / or an alkaline earth metal salt or the like is added as a flocculant having a critical coagulation concentration or higher in water containing resin particles and colorant particles Next, it is a step of performing fusion at the same time as salting-out proceeds by heating to the glass transition point or more of the resin particles. In this step, an organic solvent that is infinitely soluble in water may be added.
[0192]
Here, the alkali metal salt and the alkaline earth metal salt which are salting-out agents include lithium, potassium, sodium and the like as the alkali metal, and examples of the alkaline earth metal include magnesium, calcium, strontium and barium. Preferably, potassium, sodium, magnesium, calcium, and barium are used. Examples of the salt include chlorine salt, bromine salt, iodine salt, carbonate salt, sulfate salt and the like.
[0193]
Furthermore, examples of the organic solvent infinitely soluble in water include methanol, ethanol, 1-propanol, 2-propanol, ethylene glycol, glycerin, acetone, etc., but methanol, ethanol, 1-propanol having 3 or less carbon atoms. 2-propanol is preferable, and 2-propanol is particularly preferable.
[0194]
In the salting-out / fusion process, it is preferable to shorten the time for which the salting-out agent is left after adding the salting-out agent (time until heating is started) as short as possible. That is, after adding the salting-out agent, it is preferable to start heating the dispersion of the resin particles and the colorant particles as quickly as possible so that the temperature is equal to or higher than the glass transition temperature of the resin particles.
[0195]
The reason for this is not clear, but the agglomeration state of the particles fluctuates depending on the standing time after salting out, the particle size distribution becomes unstable, and the surface property of the fused toner fluctuates. Will occur.
[0196]
The time (starting time) until the heating is started is usually within 30 minutes, preferably within 10 minutes.
[0197]
Although the temperature which adds a salting-out agent is not specifically limited, It is preferable that it is below the glass transition temperature of a resin particle.
[0198]
Further, in the salting out / fusion step, it is necessary to quickly raise the temperature by heating, and the rate of temperature rise is preferably 1 ° C./min or more. The upper limit of the heating rate is not particularly limited, but is preferably 15 ° C./min or less from the viewpoint of suppressing the generation of coarse colored particles due to rapid salting out / fusion.
[0199]
Furthermore, after the dispersion of the resin particles and the colorant particles reaches a temperature equal to or higher than the glass transition temperature, it is important to keep salting out / fusion by maintaining the temperature of the dispersion for a certain time. . As a result, the growth of colored particles (toner particles) (aggregation of resin particles and colorant particles) and fusion (disappearance at the interface between particles) can be effectively advanced. Durability can be improved.
[0200]
Further, after the growth of the associated colored particles is stopped, the fusion by heating may be continued.
[Filtering and washing process]
In this filtration / washing step, a filtration treatment for filtering the colored particles from the dispersion of the colored particles (toner particles) obtained in the above step and an interface from the filtered colored particles (cake-like aggregate) are performed. A cleaning process is performed to remove deposits such as activators and salting-out agents.
[0201]
Here, the filtration method is not particularly limited, such as a centrifugal separation method, a vacuum filtration method using Nutsche or the like, a filtration method using a filter press or the like.
[Drying process]
This step is a step of drying the washed colored particles (toner particles).
[0202]
Examples of dryers used in this process include spray dryers, vacuum freeze dryers, vacuum dryers, etc., stationary shelf dryers, mobile shelf dryers, fluidized bed dryers, rotary dryers It is preferable to use a stirring dryer or the like.
[0203]
The water content of the dried colored particles (toner particles) is preferably 5% by mass or less, and more preferably 2% by mass or less.
[0204]
In addition, when the dried colored particles are aggregated with weak interparticle attractive force, the aggregate may be crushed. Here, as the crushing treatment apparatus, a mechanical crushing apparatus such as a jet mill, a Henschel mixer, a coffee mill, or a food processor can be used.
[External additive addition process]
This step is a step of adding an external additive to the dried colored particles (toner particles).
[0205]
Examples of the apparatus used for adding the external additive include various known mixing apparatuses such as a Turbuler mixer, a Henschel mixer, a Nauter mixer, and a V-type mixer.
[0206]
The toner particles of the present invention may be added with a material capable of imparting various functions as a toner material in addition to the colorant, the release agent, and the crystalline polyester. Specific examples include charge control agents. These components can be added simultaneously with the resin particles and the colorant particles in the salting out / fusion step described above, and can be added by various methods such as a method included in the toner and a method of adding to the resin particles themselves.
[0207]
Similarly, various known charge control agents and those that can be dispersed in water can be used. Specific examples include nigrosine dyes, naphthenic acid or higher fatty acid metal salts, alkoxylated amines, quaternary ammonium salt compounds, azo metal complexes, salicylic acid metal salts or metal complexes thereof.
[0208]
The toner of the present invention is suitably used for forming a semi-gloss image.
Here, the “semi-gloss image” refers to an image having a standard glossiness of 17 to 37. In the present invention, the standard glossiness refers to a gloss meter VGS at an incident angle of 75 ° according to JIS-Z8741-1983 method 2 in an image portion in which an image forming material (toner) covers 90% or more of an image forming support. It represents with the value measured by -1D (Nippon Denshoku Industries Co., Ltd. product). Measurement of the coating ratio of the image forming support with the image forming material was performed using a high-speed color image analyzer SPICCA (manufactured by Nippon Avionics).
[0209]
In the present invention, the standard glossiness of the semi-gloss image is 17 to 37, preferably 17 to 27. If the standard glossiness is less than 17, the image is not vivid and sufficient texture cannot be obtained. On the other hand, when the standard glossiness exceeds 37, the surface regular reflection light component is too large, a sufficient texture cannot be obtained, and the reality is insufficient. Furthermore, if the surface is smooth, the amount of light incident on the inside increases, the colorant is likely to deteriorate, and image deterioration over time occurs. For the deterioration of the colorant, the standard glossiness is particularly preferably 27 or less.
<Developer>
The toner of the present invention may be used as a one-component developer or a two-component developer.
[0210]
When used as a one-component developer, a non-magnetic one-component developer or a magnetic one-component developer containing about 0.1 to 0.5 μm of magnetic particles in the toner can be used. be able to.
[0211]
Further, it can be mixed with a carrier and used as a two-component developer. In this case, conventionally known materials such as metals such as iron, ferrite and magnetite, and alloys of these metals with metals such as aluminum and lead can be used as the magnetic particles of the carrier. Ferrite particles are particularly preferable. The magnetic particles preferably have a volume average particle size of 15 to 100 μm, more preferably 25 to 80 μm.
[0212]
The volume average particle diameter of the carrier can be typically measured by a laser diffraction particle size distribution measuring apparatus “HELOS” (manufactured by SYMPATEC) equipped with a wet disperser.
[0213]
The carrier is preferably a carrier in which magnetic particles are further coated with a resin, or a so-called resin dispersion type carrier in which magnetic particles are dispersed in a resin. The resin composition for coating is not particularly limited, and for example, olefin resin, styrene resin, styrene-acrylic resin, silicone resin, ester resin, or fluorine-containing polymer resin is used. In addition, the resin for constituting the resin-dispersed carrier is not particularly limited, and a known resin can be used. For example, a styrene-acrylic resin, a polyester resin, a fluorine resin, a phenol resin, or the like is used. be able to.
[0214]
【Example】
Examples of the present invention will be described below, but the present invention is not limited to these examples. In the following, “part” means “part by mass”.
[Preparation Example HP-1]
Surfactant prepared by dissolving 7.08 g of an anionic surfactant (sodium dodecyl sulfonate: SDS) in 2760 g of ion-exchanged water in a 5000 ml separable flask equipped with a stirrer, temperature sensor, condenser, and nitrogen introducing device The solution (aqueous medium) was charged, and the internal temperature was raised to 80 ° C. while stirring at a stirring speed of 230 rpm under a nitrogen stream.
[0215]
An initiator solution prepared by dissolving 0.42 g of a polymerization initiator (potassium persulfate: KPS) in 200 g of ion-exchanged water was added to this surfactant solution, and the temperature was adjusted to 75 ° C. Then, 115.1 g of styrene, n -A monomer mixture composed of 42.0 g of butyl acrylate and 10.9 g of methacrylic acid was added dropwise over 1 hour, and this system was heated and stirred at 75 ° C for 2 hours to obtain latex (high molecular weight resin particles Of dispersion) was prepared. This is referred to as “latex (HP-1)”.
[0216]
The peak molecular weight of the resin particles constituting this latex (HP-1) was 518,000. Further, the weight average particle diameter of the resin particles was 105 nm.
[Preparation Example HP-2]
A latex (a dispersion of high molecular weight resin particles) was prepared in the same manner as in Preparation Example HP-1, except that the reaction temperature was changed to 85 ° C. This is referred to as “latex (HP-2)”.
[0217]
The peak molecular weight of the resin particles constituting this latex (HP-2) was 421,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example HP-3]
A latex (a dispersion of high molecular weight resin particles) was prepared in the same manner as in Preparation Example HP-1, except that the addition amount of the polymerization initiator (KPS) was changed to 0.84 g. This is referred to as “latex (HP-3)”.
[0218]
The peak molecular weight of the resin particles constituting this latex (HP-3) was 316,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example HP-4]
A latex (a dispersion of high molecular weight resin particles) was prepared in the same manner as Preparation Example HP-1, except that the amount of potassium persulfate (KPS) added was changed to 0.84 g and the reaction temperature was changed to 90 ° C. did. This is referred to as “latex (HP-4)”.
[0219]
The peak molecular weight of the resin particles constituting this latex (HP-4) was 193,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-1]
In a flask equipped with a stirrer, 72.0 g of the compound represented by the above formula 19) (hereinafter referred to as “Exemplary Compound (19)”), 383.6 g of styrene, 140.0 g of n-butyl acrylate, methacryl It added to the monomer liquid mixture which consists of acid 36.4g and dodecyl mercaptan 5.6g, and it heated and melt | dissolved at 80 degreeC and prepared the monomer solution.
[0220]
On the other hand, a surfactant solution (aqueous system) obtained by dissolving 1.6 g of an anionic surfactant (SDS) in 2000 g of ion-exchanged water in a 5000 ml separable flask equipped with a stirrer, a temperature sensor, a condenser, and a nitrogen introducing device. Medium) and the internal temperature was raised to 80 ° C.
[0221]
Next, the monomer solution (80 ° C.) is mixed and dispersed in the surfactant solution (80 ° C.) by a mechanical disperser “CLEARMIX” (manufactured by M Technique Co., Ltd.) having a circulation path. A dispersion of emulsified particles (oil droplets) having a uniform dispersed particle size was prepared.
[0222]
Next, an initiator solution prepared by dissolving 19.1 g of a polymerization initiator (KPS) in 240 g of ion-exchanged water and 750 g of ion-exchanged water are added to this dispersion, and the system is heated at 80 ° C. for 3 hours. Polymerization was carried out by stirring to prepare a latex (a dispersion of intermediate molecular weight resin particles containing the exemplified compound (19)). This is referred to as “latex (MP-1)”.
[0223]
The peak molecular weight of the resin particles constituting this latex (MP-1) was 103,000. The weight average particle size of the resin particles was 108 nm.
[Preparation Example MP-2]
A dispersion of a latex (intermediate molecular weight resin particle containing exemplary compound (19) containing latex (Exemplary Compound (19)), except that the amount of dodecyl mercaptan constituting the monomer mixture was changed to 8.3 g. ) Was prepared. This is referred to as “latex (MP-2)”.
[0224]
The peak molecular weight of the resin particles constituting this latex (MP-2) was 81,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-3]
Latex (intermediate molecular weight resin particles containing Exemplified Compound (19), as in Preparation Example MP-1, except that the amount of Exemplified Compound (19) added to the monomer mixture was changed to 144.0 g Of dispersion) was prepared. This is referred to as “latex (MP-3)”.
[0225]
The peak molecular weight of the resin particles constituting this latex (MP-3) was 103,000. Further, the weight average particle diameter of the resin particles was 115 nm.
[Preparation Example MP-4]
Preparative Example MP- except that 72.0 g of the compound represented by the above formula 21) (hereinafter referred to as “Exemplary Compound (21)”) was added to the monomer mixture instead of Exemplified Compound (19). In the same manner as in Example 1, a latex (a dispersion of intermediate molecular weight resin particles containing the exemplary compound (21)) was prepared. This is referred to as “latex (MP-4)”.
[0226]
The peak molecular weight of the resin particles constituting this latex (MP-4) was 102,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-5]
Preparative Example MP- except that 72.0 g of the compound represented by the above formula 18) (hereinafter referred to as “exemplary compound (18)”) was added to the monomer mixture instead of the exemplary compound (19). In the same manner as in Example 1, a latex (a dispersion of intermediate molecular weight resin particles containing the exemplified compound (18)) was prepared. This is referred to as “latex (MP-5)”.
[0227]
The peak molecular weight of the resin particles constituting this latex (MP-5) was 102,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-6]
A latex (crystalline polyester) was prepared in the same manner as in Preparation Example MP-1, except that 80.0 g of the crystalline polyester (1) shown in Table 1 below was added to the monomer mixture instead of the exemplified compound (19). A dispersion of intermediate molecular weight resin particles containing (1) was prepared. This is referred to as “latex (MP-6)”.
[0228]
The peak molecular weight of the resin particles constituting this latex (MP-6) was 105,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-7]
A latex (dispersion of intermediate molecular weight resin particles containing crystalline polyester (1) was performed in the same manner as in Preparation Example MP-6 except that the amount of dodecyl mercaptan constituting the monomer mixture was changed to 8.3 g. Liquid). This is referred to as “latex (MP-7)”.
[0229]
The peak molecular weight of the resin particles constituting this latex (MP-7) was 79,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-8]
In place of crystalline polyester (1), latex (crystalline property) was prepared in the same manner as in Preparation Example MP-6 except that 80.0 g of crystalline polyester (2) shown in Table 1 below was added to the monomer mixture. An intermediate molecular weight resin particle dispersion containing polyester (2) was prepared. This is referred to as “latex (MP-8)”.
[0230]
The peak molecular weight of the resin particles constituting this latex (MP-8) was 104,000. Further, the weight average particle diameter of the resin particles was 115 nm.
[Preparation Example MP-9]
Instead of the crystalline polyester (1), a latex (crystalline property) was prepared in the same manner as in Preparation Example MP-6 except that 80.0 g of the crystalline polyester (3) shown in Table 1 below was added to the monomer mixture. A dispersion of intermediate molecular weight resin particles containing polyester (3) was prepared. This is referred to as “latex (MP-9)”.
[0231]
The peak molecular weight of the resin particles constituting this latex (MP-9) was 104,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-10]
Instead of the crystalline polyester (1), a latex (crystalline property) was prepared in the same manner as in Preparation Example MP-6 except that 80.0 g of the crystalline polyester (4) shown in Table 1 below was added to the monomer mixture. A dispersion of resin particles having an intermediate molecular weight containing polyester (4) was prepared. This is referred to as “latex (MP-10)”.
[0232]
The peak molecular weight of the resin particles constituting this latex (MP-10) was 101,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-11]
Instead of the crystalline polyester (1), a latex (crystalline property) was prepared in the same manner as in Preparation Example MP-6 except that 80.0 g of the crystalline polyester (5) shown in Table 1 below was added to the monomer mixture. A dispersion of intermediate molecular weight resin particles containing polyester (5) was prepared. This is referred to as “latex (MP-11)”.
[0233]
The peak molecular weight of the resin particles constituting this latex (MP-11) was 100,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-12]
Latex (intermediate molecular weight containing crystalline polyester (1) is the same as in Preparation Example MP-6 except that the amount of crystalline polyester (1) added to the monomer mixture is changed to 90.0 g. A dispersion of resin particles) was prepared. This is referred to as “latex (MP-12)”.
[0234]
The peak molecular weight of the resin particles constituting this latex (MP-12) was 103,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[Preparation Example MP-13]
Latex (intermediate molecular weight containing crystalline polyester (1) is the same as in Preparation Example MP-6 except that the amount of crystalline polyester (1) added to the monomer mixture is changed to 70.0 g. A dispersion of resin particles) was prepared. This is referred to as “latex (MP-13)”.
[0235]
The peak molecular weight of the resin particles constituting this latex (MP-13) was 107,000. Further, the weight average particle diameter of the resin particles was 110 nm.
[0236]
[Table 1]

[0237]
[Preparation Example LP-1]
In a flask equipped with a stirrer, temperature sensor, condenser, and nitrogen introducing device, a surfactant solution (aqueous medium) in which 60 g of an anionic surfactant (SDS) was dissolved in 5000 g of ion-exchanged water was charged under a nitrogen stream. The internal temperature was raised to 80 ° C. while stirring at a stirring speed of 230 rpm.
[0238]
To this surfactant solution, an initiator solution in which 22.8 g of a polymerization initiator (KPS) was dissolved in 200 g of ion-exchanged water was added, and while maintaining the temperature at 80 ° C., 850 g of styrene, 252 g of butyl acrylate, A monomer mixture composed of 98 g of acid and 32 g of t-dodecyl mercaptan was added dropwise over 1 hour, and this system was heated and stirred at 80 ° C. for 2 hours to obtain a latex (dispersion of low molecular weight resin particles). Was prepared. This is referred to as “latex (LP-1)”.
[0239]
The peak molecular weight of the resin particles constituting this latex (LP-1) was 18,000. Further, the weight average particle diameter of the resin particles was 105 nm.
[Production Example of Colored Particle 1]
90 g of sodium n-dodecyl sulfate was dissolved in 1600 ml of ion-exchanged water with stirring. While stirring this solution, 200 g of carbon black “Mogal L” (manufactured by Cabot) was gradually added, and then a stirrer “Clearmix” (manufactured by M Technique Co., Ltd.) equipped with a rotor rotating at high speed was added. A dispersion liquid of colorant particles (hereinafter referred to as “colorant dispersion liquid”) was prepared by carrying out dispersion treatment. When the particle diameter of the colorant particles in this colorant dispersion was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle diameter was 101 nm.
[0240]
3000 g of latex (HP-1) obtained in Preparation Example HP-1, 2500 g of latex (MP-1) obtained in Preparation Example MP-1 and latex (LP-1) obtained in Preparation Example LP-1 ) 6000 g, ion-exchanged water 2000 g, and colorant dispersion 1800 g were stirred in a reaction vessel equipped with a temperature sensor, a cooling tube, a nitrogen introducing device, and a stirring device. After adjusting the internal temperature to 30 ° C., 5 mol / L aqueous sodium hydroxide solution was added to this solution to adjust the pH to 11.0. Next, an aqueous solution in which 526 g of magnesium chloride hexahydrate was dissolved in 720 ml of ion-exchanged water was added over 10 minutes at 30 ° C. with stirring. After standing for 3 minutes, temperature increase was started, and the system was heated to 90 ° C. over 6 minutes (temperature increase rate = 10 ° C./min). In this state, the particle size of the associated particles was measured with “Coulter Counter TA-II”, and when the volume average particle size reached 6.5 μm, an aqueous solution in which 1150 g of sodium chloride was dissolved in 7000 ml of ion-exchanged water was added. Then, the particle growth was stopped, and the fusion was continued by heating and stirring at a liquid temperature of 85 ° C. for 2 hours as an aging treatment. Then, it cooled to 30 degreeC on the conditions of 8 degreeC / min, hydrochloric acid was added, pH was adjusted to 2.0, and stirring was stopped. The produced associated particles were filtered, washed repeatedly with ion-exchanged water, and then dried with hot air at 40 ° C. to obtain colored particles. The colored particles thus obtained are referred to as “colored particles 1”.
[Production Examples of Colored Particles 2 to 10 and Comparative Colored Particle C1]
In accordance with the formulation shown in Table 2 below, a release agent is contained in the same manner as the colored particles 1 except that at least one of the type of latex used (the amount used is the same), the aging temperature, and the aging time is changed. Colored particles were obtained. The colored particles thus obtained are referred to as “colored particles 2” to “colored particles 10” and “comparative colored particles C1”.
[Production Example of Comparative Colored Particle C2]
In a surfactant solution (85 ° C.) in which 0.5 g of an anionic surfactant (SDS) was dissolved in 400 g of ion-exchanged water, 140 g of the exemplified compound (19) dissolved by heating was ultrasonically dispersed. This dispersion is referred to as “release agent dispersion”.
[0241]
This release agent dispersion, 3000 g of latex (HP-1) obtained in Preparation Example HP-1, 6000 g of latex (LP-1) obtained in Preparation Example LP-1, 2000 g of ion-exchanged water, 1300 g of the colorant dispersion was put into a reaction vessel equipped with a temperature sensor, a cooling tube, a nitrogen introducing device, and a stirring device and stirred, and separated in the same manner as in Production Example 1Bk except that the aging time was changed to 4 hours. Colored particles containing the mold were obtained. The colored particles thus obtained are referred to as “comparative colored particles C2.”
[0242]
[Table 2]

[0243]
[Production Example of Colored Particles 11 to 23 and Comparative Colored Particle C3]
In accordance with the formulation shown in Table 3 below, the crystalline polyester is contained in the same manner as the colored particles 1 except that at least one of the type of latex used (the same amount used), the aging temperature, and the aging time is changed. Colored particles were obtained. The colored particles thus obtained are referred to as “colored particles 11” to “colored particles 23” and “comparative colored particles C3”.
[Comparison colored particles C4]
200 g of crystalline polyester (1) was ultrasonically dispersed in a surfactant solution (85 ° C.) in which 5.0 g of an anionic surfactant (SDS) was dissolved in 4000 g of ion-exchanged water. This dispersion is referred to as “crystalline polyester dispersion”.
[0244]
This crystalline polyester dispersion, 3000 g of latex (HP-1) obtained in Preparation Example HP-1, 6000 g of latex (LP-1) obtained in Preparation Example LP-1, 2000 g of ion-exchanged water, 1300 g of the colorant dispersion is put into a reaction vessel equipped with a temperature sensor, a cooling tube, a nitrogen introducing device, and a stirring device, and stirred, and crystallized in the same manner as the colored particles 1 except that the aging time is changed to 4 hours. Colored particles containing a reactive polyester were obtained. The colored particles thus obtained are referred to as “comparative colored particles C4”.
[0245]
[Table 3]

[0246]
For each of the colored particles 1 to 10 obtained as described above, the comparative colored particles C1 to C2; the colored particles 11 to 23, and the comparative colored particles C3 to C4, the shape characteristics and the particle size distribution characteristics are shown in Tables 4 to 4 below. Table 5 shows.
[0247]
[Table 4]

[0248]
[Table 5]

[0249]
Hydrophobic silica (number average primary particle size = 10 nm, hydrophobicity = 63) is added to each of the above colored particles and comparative colored particles at a ratio of 1.0% by mass, and hydrophobic titanium oxide ( (Number average primary particle size = 25 nm, hydrophobicity = 60) are added at a ratio of 1.2% by mass, mixed by a Henschel mixer, toners 1-10, comparative toners C1-C2, and toners 11-23. Also, comparative toners C3 to C4 were prepared.
[0250]
The shape and particle size of these toner particles are the same as the corresponding colored particles, and the shape and particle size do not change depending on the addition of hydrophobic silica and hydrophobic titanium oxide.
[0251]
Next, each of the colored particles to which hydrophobic silica and hydrophobic titanium oxide were added was mixed with a ferrite carrier having a volume average particle diameter of 60 μm coated with a silicone resin to prepare a developer having a toner concentration of 6% by mass. . These developers correspond to the colored particles 1 to 10, the comparative colored particles C1 to C2; the colored particles 11 to 23, and the comparative colored particles C3 to C4. C2: Developers 11 to 23 and comparative developers C3 to C4.
[Production of fixing device]
(Fixing device 1 group)
According to the configuration shown in FIG. 3, the surface of a cylindrical metal core (outer diameter = 27.5 mm, wall thickness = 0.8 mm) made of an aluminum alloy with a heater built in the center is made of ethylene tetrafluoride with a thickness of 20 μm. A heating roller is formed by coating with a perfluoroalkyl vinyl ether copolymer resin (PFA), and the surface of a cylindrical cored bar made of iron and having an outer diameter of 26 mm is coated with silicone rubber with a thickness of 5.0 mm. A pressure roller is formed by covering with a conductive tube (thickness: 50 μm) made of a fluoroethylene-perfluoroalkyl vinyl ether copolymer resin (PFA), and the heating roller and the pressure roller are combined with a total load of 127 N To form a fixing nip portion having a width of 3.5 mm. Then, according to the following Table 2, a plurality of fixing devices in which the surface roughness Sm on the surface of the heating roller was changed were produced. These are referred to as “fixing device group 1”.
(Fixing device group 2)
Using a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin (PFA) containing a carbon filler as a material for forming a release layer that covers the surface of the cored bar constituting the heating roller, heating is performed according to Table 2 below. A plurality of fixing devices having the same configuration as that of the fixing device group 1 except that the surface roughness Sm on the roller surface was changed were produced. These are referred to as “fixing device group 2”.
<Live-action test>
For each of developers 1 to 3, by performing a live-action test in which a copy image is formed in a normal temperature and humidity environment (temperature 25 ° C., relative humidity 45%), (1) offset resistance and (2) wrapping prevention characteristics Was evaluated.
[0252]
Here, as an image forming apparatus, a digital copying machine “Sitoos 7020” (manufactured by Konica Corporation) is used, and the above-described fixing device is used, and the conveyance speed of the recording material is 140 mm / sec, The fixing temperature is controlled by the surface temperature of the heating roller (set temperature 175 ° C.), and the recording material P (transfer paper) is 64 g / m.²Used copy paper.
〔Evaluation methods〕
(1) Offset resistance:
The presence / absence of occurrence of image smear due to offset when 20 copies of A3 originals with a gray scale at the front end were continuously observed was observed visually.
(2) Anti-winding properties:
The presence or absence of occurrence of paper wrapping around the heating roller when 10 copies of an A3 original document having a solid black image were made was confirmed (no occurrence: ○, occurrence: x).
[0253]
The above results are shown in Tables 6 to 15 below.
[0254]
[Table 6]

[0255]
[Table 7]

[0256]
[Table 8]

[0257]
[Table 9]

[0258]
[Table 10]

[0259]
[Table 11]

[0260]
[Table 12]

[0261]
[Table 13]

[0262]
[Table 14]

[0263]
[Table 15]

[0264]
In the above table, Y = (280-20 × D)
As described above, the toner particles having the specific shape factor of the present invention obtained by salting out / fusion of resin particles containing a release agent in a binder resin are used as the toner. According to the image forming apparatus of the present invention in which the surface roughness of the surface of the heating roller satisfies a specific condition, the image having a high image quality is excellent in anti-offset property and anti-rolling property. Can be formed. On the other hand, when the toner having a specific shape factor of the present invention obtained by salting out / fusing resin particles containing a release agent in a binder resin as a toner is used. However, with respect to the number average particle diameter of the toner particles, an image forming apparatus in which the surface roughness of the heating roller does not satisfy a specific condition is inferior in offset resistance or anti-rolling characteristics and has a practical problem. Further, when the toner (C1 to C4) whose shape factor is out of the range of the present invention is used, the offset resistance is lowered, and the range in which the winding does not occur is narrow.
[0265]
【The invention's effect】
According to the image forming apparatus of the present invention, a recording material wrapping phenomenon or an offset phenomenon hardly occurs on a rotating body having a heating source, and an image with high image quality can be stably formed.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a roughness curve for explaining surface roughness (average interval of unevenness).
FIG. 2 is an explanatory diagram showing an outline of a configuration in an example of an image forming apparatus of the present invention.
FIG. 3 is an explanatory diagram illustrating an outline of a configuration of an example of a heat roller type fixing device mounted in the image forming apparatus of the present invention.
FIG. 4 is an explanatory diagram showing an outline of a configuration of an example of a heat fixing belt type fixing device mounted on the image forming apparatus of the present invention.
FIGS. 5A and 5B are explanatory diagrams showing projected images of toner particles having no corners, and FIGS. 5B and 5C are explanatory diagrams showing projected images of toner particles having corners. FIGS.
[Explanation of symbols]
10 photoconductor
11 Charging device
12 Exposure equipment
13 Development device
14 Transfer device
15 Separation device
16 Cleaning device
20, 20A, 20B Fixing device
21, 41 Heating roller
25 Pressure roller
22, 26 Core
23, 28, 463 Release layer
27, 462 Elastic layer
30 Pressing spring
31, 41A Heating source
32 Temperature detection means
33 Original winding roller
34 Winding roller
35 Web
36 Backup Roller
37 Cleaning mechanism
42 Temperature detection means
43, 52 Cleaning roller
45 Upper pressure roller
451 Elastic member
46 Lower pressure roller
461 Thermally conductive substrate
47 Spring
50 Heat-fixing belt
51 Oil application roller
N Fixing nip
P Recording material
t Unfixed toner image

Claims (31)

Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fusion-bonding resin particles containing a release agent in a binder resin and colorant particles. An image forming apparatus comprising toner particles having the obtained colored particles as a basic component, a variation coefficient of a shape factor of 16% or less, and a number variation coefficient in a number particle size distribution of 27% or less.
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9 2. The image forming apparatus according to claim 1, wherein a ratio of toner particles having a shape factor in a range of 1.0 to 1.6 is 65% by number or more. 2. The image forming apparatus according to claim 1, wherein a ratio of toner particles having a shape factor in a range of 1.2 to 1.6 is 65% by number or more. The image forming apparatus according to claim 1, wherein the ratio of toner particles having no corners is 50% by number or more. The image forming apparatus according to claim 1, wherein the toner particles have a number average particle diameter of 3 to 8 μm. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to claim 1. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fusion-bonding resin particles containing a release agent in a binder resin and colorant particles. An image forming apparatus comprising toner particles having the obtained colored particles as a basic component, a proportion of toner particles having no corners of 50% by number or more, and a number variation coefficient in a number particle size distribution of 27% or less.
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9 8. The image forming apparatus according to claim 7, wherein the ratio of toner particles having a shape factor in the range of 1.0 to 1.6 is 65% by number or more. 8. The image forming apparatus according to claim 7, wherein a ratio of toner particles having a shape factor in a range of 1.2 to 1.6 is 65% by number or more. The image forming apparatus according to claim 7, wherein the toner particles have a number average particle diameter of 3 to 8 μm. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to claim 7. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fusion-bonding resin particles containing a release agent in a binder resin and colorant particles. The obtained colored particles are used as a basic component, and the ratio of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more, and the variation coefficient of the shape factor is 16% or less. An image forming apparatus.
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9 The image forming apparatus according to claim 12, wherein the ratio of toner particles having no corners is 50% by number or more. 14. The image forming apparatus according to claim 12, wherein the toner particles have a number average particle diameter of 3 to 8 μm. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to claim 12. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fuseting resin particles containing a crystalline polyester in a binder resin and colorant particles. An image forming apparatus comprising toner particles having the obtained colored particles as a basic component, a variation coefficient of a shape factor of 16% or less, and a number variation coefficient in a number particle size distribution of 27% or less.
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9 The image forming apparatus according to claim 16, wherein the proportion of toner particles having a shape factor in the range of 1.0 to 1.6 is 65% by number or more. The image forming apparatus according to claim 16, wherein a ratio of toner particles having a shape factor in a range of 1.2 to 1.6 is 65% by number or more. The image forming apparatus according to claim 16, wherein a ratio of toner particles having no corners is 50% by number or more. 20. The image forming apparatus according to claim 16, wherein the number average particle diameter of the toner particles is 3 to 8 [mu] m. When the particle size of toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to any one of claims 16 to 20. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle diameter [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fuseting resin particles containing a crystalline polyester in a binder resin and colorant particles. An image forming apparatus comprising toner particles having the obtained colored particles as a basic component, a proportion of toner particles having no corners of 50% by number or more, and a number variation coefficient in a number particle size distribution of 27% or less.
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9 23. The image forming apparatus according to claim 22, wherein the proportion of toner particles having a shape factor in the range of 1.0 to 1.6 is 65% by number or more. 23. The image forming apparatus according to claim 22, wherein a ratio of toner particles having a shape factor in a range of 1.2 to 1.6 is 65% by number or more. 25. The image forming apparatus according to claim 22, wherein the toner particles have a number average particle diameter of 3 to 8 [mu] m. When the particle size of toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. The image forming apparatus according to any one of claims 22 to 25. Two rotating bodies that are pressed against each other to form a fixing nip portion are provided. A heating source is provided in at least one of the rotating bodies, and an unfixed toner image formed on the recording material is formed in the fixing nip portion. In an image forming apparatus equipped with a fixing device for heat fixing, when the number average particle size [μm] of toner particles constituting an unfixed toner image is D, the surface roughness Sm of the rotating body in contact with the unfixed toner image [Μm] has a relationship of D and the following general formula (1), and the toner is obtained by salting out / fuseting resin particles containing a crystalline polyester in a binder resin and colorant particles. The obtained colored particles are used as a basic component, and the ratio of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more, and the variation coefficient of the shape factor is 16% or less. An image forming apparatus.
General formula (1) (280-20 * D) <= Sm <= 300
However, D = 2-9 28. The image forming apparatus according to claim 27, wherein a ratio of toner particles having no corners is 50% by number or more. 29. The image forming apparatus according to claim 27 or 28, wherein the number average particle diameter of the toner particles is 3 to 8 [mu] m. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is the mode of the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. The sum (M) of the relative frequency (m1) of the toner particles contained and the relative frequency (m2) of the toner particles contained in the next most frequent class is 70% or more. 30. The image forming apparatus according to claim 27. 31. An image forming method using the image forming apparatus according to claim 1.

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