JP3788940B2 - Coloring composition for image recording and image recording agent - Google Patents

Description

（但し、式中の、Ａはベンゼン環、Ｘは−ＣＯＮＨＲ基（Ｒは水素、アルキル基、またはアリール基を表し、アリール基はハロゲン、ニトロ基およびアルキル基から選ばれる少なくとも１種の置換基で置換されていても良い。）、Ｙは水素、またはハロゲン、アルキル基、アルコキシ基、およびニトロ基から選ばれる少なくとも１種の置換基である。）
【０００９】
【発明の実施の形態】
以下に本発明を更に詳細に説明する。
本発明の顔料および樹脂とからなる画像記録用着色組成物は、顔料として、ｐ−トルイジン−ｍ−スルホン酸のジアゾニウム塩とβ−オキシナフトエ酸とをカップリングし、カップリング後、またはカップリングと同時にカルシウムにてレーキ化してＣ. Ｉ. ピグメントレッド５７：１を合成する際に、ｐ−トルイジン−ｍ−スルホン酸の一部を前記の一般式（１）で表される極性基を有するベンゼン系アミンで置換して得られるアゾレーキ顔料組成物を使用することを特徴としている。
【００１０】
本発明で使用されるアゾレーキ顔料組成物は、Ｃ. Ｉ. ピグメントレッド５７：１を合成するに当たり、それと色や物性は類似しているが、構造の異なるアゾ顔料化合物を同時に合成することにより、生成した複数種の顔料粒子が混晶ないしは微結晶混合物あるいは局部的な無定形物の混在といった様な状態となって結晶の成長を抑制する効果をもたらし、その結果、上記で述べた様な加熱条件下での耐熱性が向上し、このアゾ顔料組成物を用いた画像記録剤により、色相の鮮明な、冴え、透明性を有する優れた画像が得られるものと考えられる。
【００１１】
Ｃ. Ｉ. ピグメントレッド５７：１およびその製造方法自体は周知であり、本発明では、ｐ−トルイジン−ｍ−スルホン酸の好ましくは０．１〜３０モル％を前記の一般式（１）で表される極性基を有するベンゼン系アミンにより置換して混合ジアゾ成分とし、これを常法によりジアゾ化し、得られるジアゾ化物とβ−オキシナフトエ酸とをカップリングして染料を合成し、該染料をカルシウムでレーキ化するか、またはジアゾ化液に予めカルシウムを添加してカップリングと同時にレーキ化して得られるアゾレーキ顔料組成物を使用することを特徴としている。上記の極性基を有するベンゼン系アミンの使用量が０．１モル％未満である場合には、本発明の目的とする効果が十分でなく、一方、３０モル％を越える使用量になると、アゾレーキ顔料の本来の優れた性質が低下するので好ましくない。特に効果的な該ベンゼン系アミンの使用量は、全ジアゾ成分中で０．１〜１０モル％を占める量である。
【００１２】
本発明で使用されるアゾレーキ顔料組成物は、その製造時におけるジアゾ液、下漬液、染料あるいは顔料スラリーの適当な段階で、各種の脂肪族アミン、水溶性樹脂、界面活性剤、その他の添加剤を本発明の目的を妨げない程度の量で加えて顔料組成物の更なる処理を行うこともできる。
【００１３】
本発明で使用される下記の一般式（１）で表される極性基を有するベンゼン系アミン（以下では極性ベンゼン系アミンと称することがある。）において、Ａはベンゼン環、Ｘは−ＣＯＮＨＲ基（Ｒは水素、メチル基、エチル基、プロピル基等のアルキル基またはアリール基を表し、アリール基は塩素、臭素、沃素等のハロゲン、ニトロ基およびメチル基、エチル基、プロピル基等のアルキル基から選ばれる少なくとも１種の置換基で置換されていても良い。）、Ｙは、水素、塩素、臭素、沃素等のハロゲン、メチル基、エチル基、プロピル基等のアルキル基、メトキシ基、エトキシ基、ブトキシ基等のアルコキシ基およびニトロ基から選択される少なくとも１種の置換基である。

【００１４】
極性ベンゼン系アミンとしては、例えば、４−アミノ−ベンズアミド、３−アミノ−４−クロロ−ベンズアミド、３−アミノ−４−メチル−ベンズアミド、３−アミノ−４−メトキシ−ベンズアミド、４−アミノ−ベンズアニリド、３−アミノ−４−メトキシ−ベンズアニリド、３−アミノ−２′−クロロ−４−メトキシ−ベンズアニリド、３−アミノ−３′−クロロ−４−メトキシ−２′−メチル−ベンズアニリド等が挙げられる。これらはいずれも工業的に入手しやすく且つ効果的なものである。勿論、これらの極性基を有するベンゼン系アミンは一種を用いても、併用しても良い。
【００１５】
本発明の画像記録用着色組成物において使用される樹脂は、固体状態の該着色組成物にあっては、顔料の分散媒体であり、液体の状態の該着色組成物にあっては顔料の分散助剤として機能するものであり、また、実際に記録剤として使用されたときは被記録媒体への顔料の固着剤として作用するものである。この様な目的で使用される樹脂としては、電子写真、電子印刷、静電印刷、静電記録等の乾式現像剤及び湿式現像剤、熱転写インクリボンおよびフィルム、油性および水性インクジェットインク等の画像記録剤に従来から使用されている樹脂がいずれも使用でき、特に制限されない。また、必要に応じ、画像記録用着色組成物の用途に合わせて、各用途で従来から用いられている種々の添加剤、例えば、帯電制御剤、流動化剤等、あるいは媒体として溶剤、水系媒体等が使用される。
また、本発明の画像記録用着色組成物には前記のアゾレーキ顔料組成物を高濃度で含む高濃度着色組成物も含まれる。その目的は、顔料を高濃度に含み、予め充分に練肉して分散させたり、調色を行なっておくことにより、後の工程を容易にするためのものであり、粗粒、粗粉、微粉、シート状、小塊状等の固体状、あるいはペースト状または液状のいずれの形状にても使用される。
【００１６】
本発明の画像記録用着色組成物中におけるＣ. Ｉ. ピグメントレッド５７：１を含む前記のアゾレーキ顔料組成物の含有量は、その使用する目的によって異なり、特に限定されない。前記のアゾレーキ顔料組成物を高濃度に含有する固体状、ペースト状あるいは液状の画像記録用着色組成物では、その含有量はおよそ１５〜６０重量％、好ましくは２０〜５０重量％程度であり、電子写真現像剤等の着色剤として使用される場合には、１〜１０重量％、好ましくは２〜８重量％程度であり、熱転写インクリボンやフィルムの着色剤として使用される場合には、２〜２０重量％、好ましくは４〜１５重量％程度であり、使用する目的に応じて最も好ましい含有量で使用される。
【００１７】
【実施例】
次に実施例および比較例を挙げて本発明を更に具体的に説明する。尚、文中、部または％とあるのは特に断りの無い限り重量基準である。
【００１８】
実施例１
１−アミノ−４−メチルベンゼン−２−スルホン酸１７．８部と水酸化ナトリウム３．８部とを水３６０部に加え、常温で撹拌溶解する。この溶液に３５％塩酸２５部を加えて溶液を酸性とした後、次いで、４−アミノ−ベンズアミド０．６８部（全ジアゾ成分の５モル％）を加えて溶解し、氷を投入して５℃とする。
次に、上記の溶液に、亜硝酸ソーダ６部を水２０部に溶解した溶液を一気に加えてジアゾ化し、５〜８℃で３０分間撹拌してジアゾ液とする。
一方、水８００部にβ−オキシナフトエ酸１８．８部と水酸化ナトリウム１０．０部とを加えて撹拌溶解し、水量を１０００部に、温度を１０℃に調整して下漬液とする。
【００１９】
上記ジアゾ液を、この下漬液に２０分間で滴下してカップリング反応させて染料を合成した後、１時間撹拌する。次いで、反応液のｐＨを１０〜１１に調整し、ロジンソープ（ガムロジン３．２部（顔料に対し７％）と水酸化ナトリウム０．４部とを水６０部に溶解した溶液）を添加した後、塩化カルシウム（２水塩）１９部（染料１モルに対し１．３モルの割合）を加えてレーキ化する。１時間撹拌した後、８０℃に昇温し、濾過および水洗してプレスケーキとし、また、その一部を乾燥および粉砕して粉末とし、本発明の赤色アゾレーキ顔料組成物（乾燥収量４５．６部）を得た。
【００２０】
上記で得たアゾレーキ顔料組成物３０部を、スチレン−メタクリレート系共重合樹脂（軟化点約１１０℃、ガラス転移点約５６℃、ＧＰＣで測定した重量平均分子量（標準ポリスチレン換算の）約９万）７０部と三本ロールにて充分混練し、顔料を分散させた。冷却後粗砕して、赤色顔料を３０％の濃度で含有する高濃度着色組成物の粗粉を得た。
【００２１】
次に、この様にして得た赤色顔料を含む高濃度着色組成物１４．７部およびクロム錯塩系負帯電制御剤３部を上記で使用したスチレン−メタクリレート系共重合樹脂８２．３部と常法に従って混練し、冷却後粗砕した後、ジェットミルで微粉砕し、更に分級して５〜３０μｍの赤色樹脂組成物の微粉末を得た。この微粉末に、常法に従い流動化剤としてコロイダルシリカを添加し、充分混合し、赤色（マゼンタ色）電子写真乾式現像剤とした。これをキャリアの磁性鉄粉と混合し、負電荷フルカラー現像用電子写真複写機にて複写用紙に単色の複写をした結果、鮮明な赤色画像が得られた。画像は鮮明で冴えた赤色を呈し、耐光性等の諸物性に優れた堅牢性を示した。また、同様にしてオーバーヘッドプロジェクター用のポリエステルシートに複写すると透明な画像を呈し、オーバーヘッドプロジェクタースクリーンに鮮明な赤色の映像を示した。
【００２２】
また、シアン顔料として銅フタロシアニンブルー顔料、イエロー顔料としてモノアゾイエロー顔料、ブラック顔料としてカーボンブラック顔料を用いて上記と同様にして各々シアン色現像剤、イエロー色現像剤、ブラック色現像剤を調製し、上記で得たマゼンタ色と共に四色フルカラー複写を行い、鮮明なフルカラー画像を得た。同様にしてオーバーヘッドプロジェクターシートに複写した結果、スクリーンに鮮明なフルカラー映像を映すフルカラー画像を得た。
【００２３】
実施例２
４−アミノ−ベンズアミドの代わりに３−アミノ−４−クロロ−ベンズアミド０．８５部（全ジアゾ成分の５モル％）を使用した他は実施例１と同様にしてアゾレーキ顔料組成物を得た。得られたアゾレーキ顔料組成物を、実施例１で述べた方法に従って高濃度着色組成物を作り、更にそれを使用して電子写真用乾式現像剤を作成した。これをキャリアと混合し、フルカラー電子写真複写機にて単色及びフルカラーの複写をした結果、鮮明な画像が得られた。画像は鮮明で冴えた赤色及び四色フルカラー画像を示し、諸物性に優れた堅牢性を示した。
【００２４】
実施例３
４−アミノ−ベンズアミドの代わりに３−アミノ−４−メチル−ベンズアミド０．３７部（全ジアゾ成分の２．５モル％）と３−アミノ−４−メトキシ−ベンズアミド０．４１部（全ジアゾ成分の２．５モル％）を使用した他は実施例１と同様にしてアゾレーキ顔料組成物を得た。得られたアゾレーキ顔料組成物を実施例１で述べた方法に従って使用して高濃度着色組成物を作り、更にそれを使用して電子写真用乾式現像剤を作成した。これをキャリアと混合し、フルカラー電子写真複写機にて単色及びフルカラーの複写をした結果、鮮明な画像が得られた。画像は鮮明で冴えた赤色及び四色フルカラー画像を示し、諸物性に優れた堅牢性を示した。
【００２５】
実施例４
４−アミノ−ベンズアミドの代わりに３−アミノ−４−メトキシ−ベンズアミド０．８３部（全ジアゾ成分の５モル％）を使用した他は実施例１と同様にしてアゾレーキ顔料組成物を得た。得られたアゾレーキ顔料組成物１０部をエステルワックス４１部、パラフィン系ワックス４１部、スチレン−メタクリレート系共重合樹脂５部およびシリカ３部をバインダーとして含む着色組成物を作製し、常法に従てポリエチレンフィルムに塗布し、赤色（マゼンタ色）熱転写記録用インクフィルムとした。これを用いてフルカラー熱転写複写機にて紙に複写し、鮮明な赤色複写画像を得た。この画像は、耐光性等の諸物性に優れた堅牢性を示した。また、オーバーヘッドプロジェクター用のポリエステルシートに複写すると、透明な画像が得られ、スクリーンに鮮明な画像を示した。
【００２６】
さらに、銅フタロシアニンブルー顔料、モノアゾイエロー顔料、カーボンブラック顔料を用いて上記と同様にして、それぞれシアン色、イエロー色およびブラック色の熱転写インクフィルムを作製し、上記で得たマゼンタ色熱転写インクフィルムと共に、四色フルカラー複写を行い、鮮明なフルカラー複写画像を得た。同様にしてオーバーヘッドプロジェクター用のポリエステルシートに複写した結果、スクリーンに透明なフルカラー映像を映すフルカラー画像を得た。
【００２７】
実施例５
実施例４で得たアゾレーキ顔料組成物５部、水溶性スチレン−アクリレート−メタクリル酸ジエタノールアミン塩共重合体３部、エチレングリコール２２部、グリセリン８部及び水６２部の水性顔料分散液を常法に従って作り、超遠心分離機で分散し得なかった顔料粗粒子を除去し、インクジェット用水性赤色インキを得た。この赤色インキを用いてピエゾ振動子を有するオンデマンド型のインクジェットプリンターで画像情報をプリントし、鮮明な赤色画像を得た。
また、銅フタロシアニンブルー顔料、モノアゾイエロー顔料、カーボンブラック顔料を用いて、上記と同様にして調製したシアン色、イエロー色およびブラック色のインクジェットインキと共に、四色フルカラープリントを行い、鮮明なフルカラー画像を得た。
【００２８】
比較例１
１−アミノ−４−メチルベンゼン−２−スルホン酸１８．７部と水酸化ナトリウム４．０部とを水３６０部に加え、常温で撹拌溶解する。この溶液に３５％塩酸２５部を加え、氷を投入して５℃とする。次に、上記の溶液に、亜硝酸ソーダ６部を水２０部に溶解した溶液を一気に加えてジアゾ化し、５〜８℃で３０分間撹拌してジアゾ液とする。
一方、水８００部にβ−オキシナフトエ酸１８．８部と水酸化ナトリウム１０．０部とを加えて撹拌溶解し、水量を１０００部に、温度を１０℃に調整して下漬液とする。
【００２９】
上記ジアゾ液を、この下漬液に２０分間で滴下してカップリング反応させて染料を作製した後、１時間撹拌する。次いで反応液のｐＨを１０〜１１に調整し、ロジンソープ（ガムロジン３．２部（顔料に対し７％）と水酸化ナトリウム０．４部とを水６０部に溶解した溶液）を添加後、塩化カルシウム（２水塩）１９部（染料１モルに対し１．３モル）を加えてレーキ化する。１時間後、８０℃に昇温し、濾過および水洗してプレスケーキとし、その一部を乾燥及び粉砕して粉末とし、アゾレーキ顔料組成物を得た。得られたアゾレーキ顔料組成物を用いて実施例１で述べた方法に従って高濃度着色組成物を作り、更にそれを使用して電子写真用乾式現像剤を作製した。これをキャリアと混合し、フルカラー電子写真複写機にて単色の複写をした結果、鮮明度の劣る不透明な赤色画像しか得られなかった。
【００３０】
【発明の効果】
本発明の画像記録用着色組成物は、その顔料成分として混合アゾ成分を用いて合成した特定のＣ. Ｉ. ピグメントレッド５７：１を使用するが、それによって従来のＣ．Ｉ．ピグメントレッド５７：１の使用では得られない、高い着色力、鮮明性、冴え、透明性が得られ、更に、耐熱性等の諸堅牢性に優れていることから、画像記録用着色組成物の製造工程における熱履歴に対しても安定であり、この画像記録用着色組成物を画像記録剤として使用した場合には鮮明で冴えた、透明感の高い画像を安定して記録することができる。また、液体記録剤として使用する際にも、長期間安定に記録することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image recording agent in image recording such as electrophotography, electronic printing, electrostatic printing, electrostatic recording, ink jet recording, and thermal transfer recording, or a coloring composition used in the production thereof. More specifically, the present invention relates to CI Pigment Red 57: 1 having high transparency and sharpness obtained by using a mixed diazo component as a pigment, which is suitable for a recording agent for image recording containing a pigment and a resin. The present invention relates to a coloring composition for image recording using a pigment composition.
[0002]
[Prior art]
Conventionally, in magenta recording agents used for image recording such as full-color or mono-color electrophotography, electronic printing, electrostatic printing, electrostatic recording, inkjet recording, and thermal transfer recording, a red oil-soluble dye as a red pigment, a dispersion Dyes, thioindigo pigments, soluble azo lake pigments, insoluble azo pigments, dimethylquinacridone pigments and the like are used.
[0003]
[Problems to be solved by the invention]
Among the red pigments used in the above-described magenta color recording agent, the soluble azo lake pigment CI Pigment Red 57: 1 is close to the standard magenta hue. However, in the production of an electrophotographic dry developer or the like, it is often heated and kneaded at a temperature of about 100 to 150 ° C. Under such heating conditions, the pigment grows particles or changes in crystals. In many cases, the color tone changes, the color becomes dull, the color density decreases, or the color becomes opaque.
[0004]
Conventionally, when azo pigments are used for coloring paints, plastics, synthetic fibers, etc., the emphasis is placed on the color concealment and coloration. Heat resistance is increased by reducing the rate. However, in that case, the colorant for the image recording agent lacks the clearness, hue and transparency of the hue. Since the image recording agent is used in full color or copied on a transparent PET film for an overhead projector, it is important that the hue of the hue is clear, clear, and transparent.
[0005]
In order to improve the above drawbacks, for example, use of an azo pigment composition having a specific aspect ratio, specific surface area, and average particle size has been proposed (Japanese Patent Laid-Open No. 10-73963). However, it is still insufficient for practical use.
Accordingly, an object of the present invention is to provide a coloring composition for image recording excellent in various performances including heat-resistant fastness that does not change the vividness, hue, transparency, etc. of hue due to the heat history in kneading or the like. .
[0006]
In order to solve the above-mentioned drawbacks of the conventional recording agents, the present inventors have developed C.I. Pigment Red 57: 1 in order to develop an image recording agent that is excellent in coloration and can satisfy various fastnesses and economical efficiency. As a result of various studies on the above, as a result of using a mixed diazo component obtained by substituting a part of its diazo component, p-toluidine-m-sulfonic acid, with a benzene-based amine having a polar group, C. I. Pigment Red 57: 1 has improved heat resistance, and exhibits excellent properties such as hue clarity, clarity, and transparency, and is used as a colorant for an image recording agent. The present invention has been completed.
[0007]
[Means for Solving the Problems]
The above object is achieved by the present invention described below. That is, the present invention provides a coloring composition for image recording comprising a pigment and a resin, wherein a diazonium salt of p-toluidine-m-sulfonic acid and β-oxynaphthoic acid are coupled as a pigment, after coupling, or When synthesizing CI Pigment Red 57: 1 by calcination with calcium simultaneously with coupling, a part of p-toluidine-m-sulfonic acid is represented by the following general formula (1) An azo lake pigment composition obtained by substituting with a benzene-based amine having a color composition for image recording.
[0008]

(In the formula, A represents a benzene ring, X represents a -CONHR group (R represents hydrogen, an alkyl group, or an aryl group, and the aryl group represents at least one substituent selected from a halogen, a nitro group, and an alkyl group) Y is hydrogen or at least one substituent selected from a halogen, an alkyl group, an alkoxy group, and a nitro group.)
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described in further detail below.
The coloring composition for image recording comprising the pigment and the resin of the present invention comprises a coupling of a diazonium salt of p-toluidine-m-sulfonic acid and β-oxynaphthoic acid as a pigment, after coupling, or coupling At the same time, when C.I. Pigment Red 57: 1 is synthesized by lake with calcium, a part of p-toluidine-m-sulfonic acid has a polar group represented by the above general formula (1). An azo lake pigment composition obtained by substituting with a benzene amine is used.
[0010]
In synthesizing CI Pigment Red 57: 1, the azo lake pigment composition used in the present invention is similar in color and physical properties, but simultaneously synthesizes azo pigment compounds having different structures. The resulting multiple types of pigment particles are in a mixed crystal or microcrystal mixture or a mixture of local amorphous materials, and have the effect of suppressing crystal growth. As a result, heating as described above The heat resistance under the conditions is improved, and an image recording agent using this azo pigment composition is considered to provide an excellent image having a clear hue and a clear hue.
[0011]
CI Pigment Red 57: 1 and its production method itself are well known. In the present invention, preferably 0.1 to 30 mol% of p-toluidine-m-sulfonic acid is represented by the above general formula (1). Substituting with a benzene-based amine having a polar group to give a mixed diazo component, which is diazotized by a conventional method, and coupling the resulting diazotized product with β-oxynaphthoic acid to synthesize a dye, It is characterized by using an azo lake pigment composition obtained by lake formation with calcium or by adding calcium to a diazotization solution in advance and rake formation simultaneously with coupling. When the amount of the benzene-based amine having a polar group is less than 0.1 mol%, the intended effect of the present invention is not sufficient. On the other hand, when the amount exceeds 30 mol%, the azo lake is used. This is not preferable because the original excellent properties of the pigment are deteriorated. A particularly effective amount of the benzene-based amine is 0.1 to 10 mol% in all diazo components.
[0012]
The azo lake pigment composition used in the present invention is prepared at various stages of diazo liquid, undercoating liquid, dye or pigment slurry at the time of production, and various aliphatic amines, water-soluble resins, surfactants and other additives. Can be added in an amount that does not interfere with the purpose of the present invention for further processing of the pigment composition.
[0013]
In the benzene amine having a polar group represented by the following general formula (1) used in the present invention (hereinafter sometimes referred to as polar benzene amine), A is a benzene ring, X is a -CONHR group. (R represents an alkyl group or aryl group such as hydrogen, methyl group, ethyl group or propyl group, and the aryl group represents halogen such as chlorine, bromine or iodine, nitro group and alkyl group such as methyl group, ethyl group or propyl group. And Y is a halogen such as hydrogen, chlorine, bromine and iodine, an alkyl group such as a methyl group, an ethyl group and a propyl group, a methoxy group and an ethoxy group. And at least one substituent selected from an alkoxy group such as a butoxy group and a nitro group.

[0014]
Examples of polar benzene-based amines include 4-amino-benzamide, 3-amino-4-chloro-benzamide, 3-amino-4-methyl-benzamide, 3-amino-4-methoxy-benzamide, 4-amino-benzanilide. 3-amino-4-methoxy-benzanilide, 3-amino-2'-chloro-4-methoxy-benzanilide, 3-amino-3'-chloro-4-methoxy-2'-methyl-benzanilide and the like. These are all industrially easily available and effective. Of course, benzene type amines having these polar groups may be used singly or in combination.
[0015]
The resin used in the colored composition for image recording of the present invention is a pigment dispersion medium in the colored composition in the solid state, and the pigment dispersion in the colored composition in the liquid state. It functions as an auxiliary agent, and when it is actually used as a recording agent, it acts as a pigment fixing agent to a recording medium. Resins used for such purposes include dry developers and wet developers for electrophotography, electronic printing, electrostatic printing, electrostatic recording, etc., image recording such as thermal transfer ink ribbons and films, oil-based and aqueous inkjet inks, etc. Any resin conventionally used for the agent can be used and is not particularly limited. Further, if necessary, various additives conventionally used in each application according to the use of the coloring composition for image recording, such as a charge control agent, a fluidizing agent, etc., or a solvent, an aqueous medium as a medium Etc. are used.
In addition, the coloring composition for image recording of the present invention includes a high-concentration coloring composition containing the azo lake pigment composition at a high concentration. Its purpose is to contain the pigment in a high concentration, disperse it by thoroughly kneading in advance, or toning, to facilitate the subsequent steps, coarse particles, coarse powder, It can be used in a solid form such as a fine powder, a sheet form, a small lump form, or a paste form or a liquid form.
[0016]
The content of the azo lake pigment composition containing CI Pigment Red 57: 1 in the coloring composition for image recording of the present invention varies depending on the purpose of use and is not particularly limited. In the solid, pasty or liquid colored composition for image recording containing the azo lake pigment composition at a high concentration, the content thereof is about 15 to 60% by weight, preferably about 20 to 50% by weight, When used as a colorant such as an electrophotographic developer, it is 1 to 10% by weight, preferably about 2 to 8% by weight. When used as a colorant for a thermal transfer ink ribbon or film, 2% is used. It is about -20% by weight, preferably about 4-15% by weight, and is used in the most preferable content depending on the purpose of use.
[0017]
【Example】
Next, the present invention will be described more specifically with reference to examples and comparative examples. In the text, “part” or “%” is based on weight unless otherwise specified.
[0018]
Example 1
17.8 parts of 1-amino-4-methylbenzene-2-sulfonic acid and 3.8 parts of sodium hydroxide are added to 360 parts of water, and stirred and dissolved at room temperature. To this solution was added 25 parts of 35% hydrochloric acid to make the solution acidic, then 0.68 parts of 4-amino-benzamide (5 mol% of all diazo components) was added and dissolved, and ice was added thereto to add 5 parts. ℃.
Next, a solution obtained by dissolving 6 parts of sodium nitrite in 20 parts of water is added to the above solution at once, and diazotized, and stirred at 5 to 8 ° C. for 30 minutes to obtain a diazo solution.
On the other hand, 18.8 parts of β-oxynaphthoic acid and 10.0 parts of sodium hydroxide are added to 800 parts of water and dissolved by stirring. The amount of water is adjusted to 1000 parts, and the temperature is adjusted to 10 ° C. to obtain a submerged solution.
[0019]
The diazo solution is added dropwise to the submerged solution over 20 minutes to cause a coupling reaction to synthesize a dye, followed by stirring for 1 hour. Next, after adjusting the pH of the reaction solution to 10 to 11 and adding rosin soap (a solution in which 3.2 parts of gum rosin (7% based on pigment) and 0.4 parts of sodium hydroxide were dissolved in 60 parts of water). Then, 19 parts of calcium chloride (dihydrate) (a ratio of 1.3 mol to 1 mol of the dye) is added to form a lake. After stirring for 1 hour, the temperature was raised to 80 ° C., filtered and washed with water to obtain a press cake, and a part of the cake was dried and pulverized to give a powder. The red azo lake pigment composition of the present invention (dry yield 45.6). Part).
[0020]
30 parts of the azo lake pigment composition obtained above was mixed with a styrene-methacrylate copolymer resin (softening point: about 110 ° C., glass transition point: about 56 ° C., weight average molecular weight (standard polystyrene equivalent) about 90,000 measured by GPC)) 70 parts and three rolls were sufficiently kneaded to disperse the pigment. After cooling, the mixture was coarsely crushed to obtain a coarse powder of a highly concentrated colored composition containing a red pigment at a concentration of 30%.
[0021]
Next, 14.7 parts of the high-concentration coloring composition containing the red pigment thus obtained and 3 parts of the chromium complex salt-based negative charge control agent and 82.3 parts of the styrene-methacrylate copolymer resin as described above are used. The mixture was kneaded according to the method, cooled and roughly crushed, then finely pulverized with a jet mill and further classified to obtain a fine powder of a red resin composition having a size of 5 to 30 μm. To this fine powder, colloidal silica was added as a fluidizing agent according to a conventional method and mixed well to obtain a red (magenta) electrophotographic dry developer. This was mixed with the magnetic iron powder of the carrier, and a single color copy was made on a copy sheet with an electrophotographic copying machine for negative charge full color development. As a result, a clear red image was obtained. The image was clear and bright red, and showed excellent fastness with various physical properties such as light resistance. Similarly, when copied on a polyester sheet for an overhead projector, a transparent image was displayed, and a clear red image was displayed on the overhead projector screen.
[0022]
In addition, using a copper phthalocyanine blue pigment as a cyan pigment, a monoazo yellow pigment as a yellow pigment, and a carbon black pigment as a black pigment, a cyan developer, a yellow developer, and a black developer were prepared in the same manner as described above. A four-color full-color copy was performed together with the magenta color obtained above to obtain a clear full-color image. Similarly, as a result of copying on an overhead projector sheet, a full-color image showing a clear full-color image on a screen was obtained.
[0023]
Example 2
An azo lake pigment composition was obtained in the same manner as in Example 1, except that 0.85 part of 3-amino-4-chloro-benzamide (5 mol% of all diazo components) was used instead of 4-amino-benzamide. A high-concentration colored composition was prepared from the obtained azo lake pigment composition according to the method described in Example 1, and an electrophotographic dry developer was prepared using the composition. This was mixed with a carrier, and as a result of single-color and full-color copying using a full-color electrophotographic copying machine, a clear image was obtained. The images showed clear and frightening red and four-color full-color images, and showed excellent fastness with various physical properties.
[0024]
Example 3
Instead of 4-amino-benzamide, 0.37 part of 3-amino-4-methyl-benzamide (2.5 mol% of all diazo components) and 0.41 part of 3-amino-4-methoxy-benzamide (all diazo components) The azo lake pigment composition was obtained in the same manner as in Example 1, except that 2.5 mol%) was used. The resulting azo lake pigment composition was used in accordance with the method described in Example 1 to prepare a highly concentrated colored composition, which was further used to prepare an electrophotographic dry developer. This was mixed with a carrier, and as a result of single-color and full-color copying using a full-color electrophotographic copying machine, a clear image was obtained. The images showed clear and frightening red and four-color full-color images, and showed excellent fastness with various physical properties.
[0025]
Example 4
An azo lake pigment composition was obtained in the same manner as in Example 1 except that 0.83 part of 3-amino-4-methoxy-benzamide (5 mol% of all diazo components) was used instead of 4-amino-benzamide. A colored composition containing 10 parts of the obtained azo lake pigment composition, 41 parts of ester wax, 41 parts of paraffin wax, 5 parts of styrene-methacrylate copolymer resin, and 3 parts of silica as a binder was prepared. A red (magenta) thermal transfer recording ink film was applied to a polyethylene film. Using this, a full-color thermal transfer copying machine was used for copying on paper to obtain a clear red copy image. This image showed fastness excellent in various physical properties such as light resistance. When copied to a polyester sheet for an overhead projector, a transparent image was obtained and a clear image was displayed on the screen.
[0026]
Furthermore, cyan, yellow and black thermal transfer ink films were prepared using copper phthalocyanine blue pigment, monoazo yellow pigment and carbon black pigment in the same manner as described above, and together with the magenta thermal transfer ink film obtained above, Color full-color copying was performed to obtain a clear full-color copy image. In the same manner, as a result of copying on a polyester sheet for an overhead projector, a full-color image showing a transparent full-color image on a screen was obtained.
[0027]
Example 5
An aqueous pigment dispersion of 5 parts of the azo lake pigment composition obtained in Example 4, 3 parts of a water-soluble styrene-acrylate-methacrylic acid diethanolamine salt copolymer, 22 parts of ethylene glycol, 8 parts of glycerin and 62 parts of water was prepared according to a conventional method. The coarse pigment particles which were made and could not be dispersed by the ultracentrifuge were removed, and an aqueous red ink for inkjet was obtained. Using this red ink, image information was printed by an on-demand type ink jet printer having a piezo vibrator, and a clear red image was obtained.
Also, using copper phthalocyanine blue pigment, monoazo yellow pigment, and carbon black pigment, together with cyan, yellow, and black inkjet inks prepared in the same manner as described above, four-color full-color printing is performed to produce a clear full-color image. Obtained.
[0028]
Comparative Example 1
18.7 parts of 1-amino-4-methylbenzene-2-sulfonic acid and 4.0 parts of sodium hydroxide are added to 360 parts of water and dissolved by stirring at room temperature. To this solution is added 25 parts of 35% hydrochloric acid, and ice is added to bring the temperature to 5 ° C. Next, a solution obtained by dissolving 6 parts of sodium nitrite in 20 parts of water is added to the above solution at once, and diazotized, and stirred at 5 to 8 ° C. for 30 minutes to obtain a diazo solution.
On the other hand, 18.8 parts of β-oxynaphthoic acid and 10.0 parts of sodium hydroxide are added to 800 parts of water and dissolved by stirring.
[0029]
The above-mentioned diazo solution is dropped into this submerged solution over 20 minutes to cause a coupling reaction to produce a dye, followed by stirring for 1 hour. Next, the pH of the reaction solution was adjusted to 10 to 11, and rosin soap (a solution in which 3.2 parts of gum rosin (7% based on the pigment) and 0.4 parts of sodium hydroxide were dissolved in 60 parts of water) was added, followed by chlorination. 19 parts of calcium (dihydrate) (1.3 moles per mole of dye) is added to form a lake. After 1 hour, the temperature was raised to 80 ° C., filtered and washed with water to obtain a press cake, a part of which was dried and pulverized to obtain a powder, and an azo lake pigment composition was obtained. Using the resulting azo lake pigment composition, a highly concentrated colored composition was prepared according to the method described in Example 1, and further, an electrophotographic dry developer was prepared using the composition. When this was mixed with a carrier and copied in a single color with a full-color electrophotographic copying machine, only an opaque red image with inferior sharpness was obtained.
[0030]
【The invention's effect】
The coloring composition for image recording of the present invention uses a specific CI Pigment Red 57: 1 synthesized by using a mixed azo component as its pigment component, whereby conventional C.I. I. Pigment Red 57: 1 provides high coloring power, sharpness, clarity, transparency, and is excellent in various fastness properties such as heat resistance. It is stable against the heat history in the production process, and when this image recording coloring composition is used as an image recording agent, a clear and clear image with high transparency can be stably recorded. Further, even when used as a liquid recording agent, it is possible to record stably for a long period of time.

Claims (5)

In a coloring composition for image recording containing a pigment and a resin, as a pigment, a diazonium salt of p-toluidine-m-sulfonic acid and β-oxynaphthoic acid are coupled, and after coupling or simultaneously with coupling, calcium. When synthesizing and synthesizing CI Pigment Red 57: 1, a part of p-toluidine-m-sulfonic acid is a benzene-based amine having a polar group represented by the following general formula (1). A coloring composition for image recording, characterized by using an azo lake pigment composition obtained by substitution.

(In the formula, A represents a benzene ring, X represents a —CONHR group (R represents hydrogen, an alkyl group, or an aryl group, and the aryl group represents at least one substituent selected from a halogen, a nitro group, and an alkyl group) Y is hydrogen or at least one substituent selected from a halogen, an alkyl group, an alkoxy group, and a nitro group.) The coloring composition for image recording according to claim 1, wherein the benzene-based amine having a polar group represented by the general formula (1) accounts for 0.1 to 30 mol% of all diazo components. An image recording agent comprising the coloring composition for image recording according to claim 1. The image recording agent according to claim 3, further comprising at least one of a pigment and a dye exhibiting a magenta color. The image recording agent according to claim 3, which is an electrophotographic toner.