JP3660461B2 - Pressure-sensitive adhesive printing sheet - Google Patents

Description

（式中のＲは、式
【化２】

で示される基であり、ｎは重合度を示す数である）
で表わされる末端アクリル変性イソプレンゴム又はブタジエンゴムのようなゴム系プレポリマーも好ましいプレポリマーである。
【００１０】
これらのプレポリマーは、重量平均分子量２０００〜３００００の範囲のものが適当である。これよりも分子量が小さいものを用いると粘着性が大きくブロッキングなどを生じるため取り扱いが困難になるし、またこれよりも分子量の大きいものを用いると、硬化後の感圧接着性が低下する上、いったん接着した後で剥離しにくくなるので再剥離性接着用としては、利用できなくなる。
【００１１】
次に、末端不飽和基を有するプレポリマーと組み合わせて用いられる光重合性モノマーとしては、トリメチロールプロパンのプロピレンオキシド付加物のトリアクリレート又はトリメタクリレートあるいはそれと他の光重合性モノマーとの混合物を用いることが必要である。
このトリメチロールプロパンのプロピレンオキシド付加物のトリアクリレートは公知であり、例えば東亜合成株式会社から製品名「Ｍ−１２０」として市販されている。
場合により、このトリメチロールプロパンのプロピレンオキシド付加物のトリアクリレート又はトリメタクリレートと混合して用いる他の光重合性モノマーは、通常光重合性モノマーとして用いられている化合物の中から任意に選ぶことができる。
このような化合物としては、例えばアクリル酸やメタクリル酸などの不飽和カルボン酸又はそのエステル、例えばアルキル‐、シクロアルキル‐、ハロゲン化アルキル‐、アルコキシアルキル‐、ヒドロキシアルキル‐、アミノアルキル‐、テトラヒドロフルフリル‐、アリル‐、グリシジル‐、ベンジル‐、フェノキシ‐アクリレート及びメタクリレート、アルキレングリコール、ポリオキシアルキレングリコールのモノ又はジアクリレート及びメタクリレート、トリメチロールプロパントリアクリレート及びメタクリレート、ペンタエリトリットテトラアクリレート及びメタクリレートなど、アクリルアミド、メタクリルアミド又はその誘導体、例えばアルキル基やヒドロキシアルキル基でモノ置換又はジ置換されたアクリルアミド及びメタクリルアミド、ジアセトンアクリルアミド及びメタクリルアミド、Ｎ，Ｎ′‐アルキレンビスアクリルアミド及びメタクリルアミドなど、アリル化合物、例えばアリルアルコール、アリルイソシアネート、ジアリルフタレート、トリアリルイソシアヌレートなど、マレイン酸、無水マレイン酸、フマル酸又はそのエステル、例えばアルキル、ハロゲン化アルキル、アルコキシアルキルのモノ又はジマレエート及びフマレートなど、その他の不飽和化合物、例えばスチレン、ビニルトルエン、ジビニルベンゼン、Ｎ‐ビニルカルバゾール、Ｎ‐ビニルピロリドンなどが用いられる。
【００１２】
また、硬化収縮が支障となる用途の場合には、このモノマーとして、例えばイソボルニルアクリレート又はメタクリレート、ノルボルニルアクリレート又はメタクリレート、ジシクロペンテノキシエチルアクリレート又はメタクリレート、ジシクロペンテノキシプロピルアクリレート又はメタクリレートなど、ジエチレングリコールジシクロペンテニルモノエーテルのアクリル酸エステル又はメタクリル酸エステル、ポリオキシエチレン若しくはポリプロピレングリコールジシクロペンテニルモノエーテルのアクリル酸エステル又はメタクリル酸エステルなど、ジシクロペンテニルシンナメート、ジシクロペンテノキシエチルシンナメート、ジシクロペンテノキシエチルモノフマレート又はジフマレートなど、３，９‐ビス（１，１‐ビスメチル‐２‐オキシエチル）‐スピロ［５，５］ウンデカン、３，９‐ビス（１，１‐ビスメチル‐２‐オキシエチル）‐２，４，８，１０‐テトラオキサスピロ［５，５］ウンデカン、３，９‐ビス（２‐オキシエチル）‐スピロ［５，５］ウンデカン、３，９‐ビス（２‐オキシエチル）‐２，４，８，１０‐テトラオキサスピロ［５，５］ウンデカンなどのモノ‐、ジアクリレート又はモノ‐、ジメタアクリレート、あるいはこれらのスピログリコールのエチレンオキシド又はプロピレンオキシド付加重合体のモノ‐、ジアクリレート、又はモノ‐、ジメタアクリレート、あるいは前記モノアクリレート又はメタクリレートのメチルエーテル、１‐アザビシクロ［２，２，２］‐３‐オクテニルアクリレート又はメタクリレート、ビシクロ［２，２，１］‐５‐ヘプテン‐２，３‐ジカルボキシルモノアリルエステルなど、ジシクロペンタジエニルアクリレート又はメタクリレート、ジシクロペンタジエニルオキシエチルアクリレート又はメタクリレート、ジヒドロジシクロペンタジエニルアクリレート又はメタクリレートを用いることができる。
これらの光重合性モノマーは単独又は２種以上組み合わせて用いることができる。その使用量は、末端不飽和基を有するプレポリマーの重量に基づき、２倍以下、好ましくは０．５〜１．５倍の範囲内で選ばれる。
【００１３】
また、前記のプレポリマー及び光重合性モノマーとともに用いられる光重合開始剤としては、通常の感光性樹脂組成物における公知の光重合開始剤の中から任意のものを選択して用いることができる。このような光重合開始剤としては、例えばベンゾインやベンゾインエチルエーテル、ベンゾイン‐ｎ‐プロピルエーテル、ベンゾイン‐イソプロピルエーテル、ベンゾインイソブチル‐エーテルなどのベンゾインアルキルエーテル類、２，２‐ジメトキシ‐２‐フェニルアセトフェノン、ベンゾフェノン、ベンジル、ジアセチル、ジフェニルスルフィド、エオシン、チオニン、９，１０‐アントラキノン、２‐エチル‐９，１０‐アントラキノンなどが挙げられる。
これらの光重合開始剤は、それぞれ単独で用いてもよいし、２種以上を組み合わせて用いてもよい。その含有量は、通常前記プレポリマーと光重合性モノマーの合計量１００重量部当り、０．１〜１０重量部の範囲で選ばれる。
【００１４】
本発明で用いる放射線硬化型感圧接着剤には、所望に応じ、重ね合わせたのち経時的に接着力が増加して剥離しにくくなるのを抑制したり、ブロッキングを防止するために微粒子充填剤を含有させることができる。このような微粒子充填剤としては、前記した３成分との親和力が小さいものであって、接着層が透明性を阻害しないようにする必要から、粒子形状が規則的に整ったものを用いるのがよい。このようなものとしては、例えば、各種デンプン系、合成ゼオライト、微球状アクリル樹脂、微球状メタクリル樹脂、微球状ポリエチレン、球状アルミナ、ガラス粉末、シラスバルーン、活性白土などが挙げられる。これらの充填剤は、単独で用いてもよいし、２種以上組み合わせて用いてもよい。しかしながら、従来からこの種の接着剤組成物の充填剤として使用されているシリカ、酸化チタン、酸化亜鉛などは、その粒子形状が不規則なため、接着層に光の乱反射作用を促して透明性を損なうおそれがあるので、これらは添加しない方が好ましいが、添加する場合には、その添加量を１０重量％以下にするのがよい。なお、これらの微粒子充填剤は、その平均粒子径が１〜２０μｍ、好ましくは２〜５μｍの範囲にあるものが好適である。
【００１５】
この微粒子充填剤を含有させる場合には、その配合割合を適切に選ぶことが必要である。微粒子充填剤の配合量が少なすぎると、耐ブロッキング性が低下したり、また、接着力が強すぎて剥離しにくくなるし、また、多すぎると接着力が低くなりすぎ、十分な粘着性を示さなくなる。したがって、微粒子充填剤の配合割合は、放射線硬化型感圧接着剤全量を１００重量部としたとき、微粒子充填剤が１００〜３００重量部、好ましくは１３０〜２５０重量部、より好ましくは１５０〜２００重量部になる範囲で選ぶのがよい。
【００１６】
本発明における放射線硬化型感圧接着剤層を構成する感光性組成物には、前記した４成分に加えてさらに、所望に応じて一般の感光性樹脂組成物において慣用されている添加成分、例えば熱重合禁止剤、粘着付与剤、粘度調整剤、老化防止剤、安定剤、着色剤、微粒子充填剤などを含有させることができる。この熱重合禁止剤としては、例えばヒドロキノン、モノ第三ブチルヒドロキノン、ベンゾキノン、２，５‐ジフェニル‐ｐ‐ベンゾキノン、ピクリン酸、ジ‐ｐ‐フルオロフェニルアミン、ジ‐ｐ‐メトキシフェノール、２，６‐ジ第三ブチル‐ｐ‐クレゾールなどを挙げることができる。これらの熱重合禁止剤は、熱重合反応を防止するためのものであり、したがって、該熱重合禁止剤の含有量は、通常レジン基剤１００重量部当り、０．０１〜５重量部の範囲で選ばれる。
【００１７】
本発明の感圧接着性プリント用シートは、例えば次のようにして製造することができる。
すなわち、所定の基体シートを、二つ折り、三つ折り、切り重ね、あるいは別体同士の重ね合わせなどにより対向する部分に、グラビアコーター、フレキソ、エアナイフコーター、バーコーターなどの塗布手段により、前記した放射線硬化型感圧接着剤を塗布し、次いで乾燥することにより接着剤層を形成させる。この際の塗布は、基体シート表面の全面にわたって行ってもよいし、一部分の表面のみに行ってもよい。この基体シート表面には、あらかじめ所要の情報を印刷しておいてもよいし、接着剤層を塗布したのち、情報を印刷してもよい。この際、印刷に紫外線硬化型インキを用いて、一般的に使用されている印刷機により情報を印刷する場合には、この印刷工程と放射線硬化型感圧接着剤の塗布、定着と同時に行うことができるので有利である。
【００１８】
本発明において、基体シートとして、ポリエチレン、ポリプロピレン、ポリエチレンテレフタレート、ポリ塩化ビニルなどの合成フィルムを用いる場合には、基体シートの表面をマット処理、コロナ処理などの表面処理を施すのが好ましい。また、基体シート面への接着剤の塗布量は、接着層の接着性、剥離性、あるいは透明性の維持のため、１〜３０ｇ／ｍ²、好ましくは３〜２０ｇ／ｍ²、さらに好ましくは５〜１５ｇ／ｍ²の範囲内になるように選ばれる。
【００１９】
このようにして製造された感圧接着性プリント用シートは、紫外線、電子線、Ｘ線、ｉ線、ｇ線などの放射線を照射させて、接着剤層を適度に硬化させたのち、各面の硬化した接着剤層を重ね合わせ、例えば加圧ローラによって約１〜１００ｋｇ／ｃｍ²の圧力下で接着させる。
【００２０】
本発明における放射線硬化型感圧接着剤の硬化層の永久接着性や再剥離接着性は、末端に不飽和性基を有するプレポリマーと光重合性モノマーの種類、両者の使用割合、光重合性モノマーの官能基数、接着時のローラ圧などを変えることによって調整することができる。一般に、光重合性モノマーの官能基が多いほど接着面が硬くなり、接着力が低下するし、また接着時のローラ圧が大きくなるほど接着力が増大する。
【００２１】
次に、本発明の感圧接着性プリント用シートの構成例について添付図面に従って詳細に説明するが、本発明はこれらの構成例によって限定されるものではない。なお、ここにおいて、図１は本発明の第一の構成例である、線状に放射線硬化型接着剤の硬化層が施されてなる三つ折り感圧接着性プリント用シートの平面図、図２は図１の感圧接着性プリント用シートの裏面図、図３は図１の感圧接着性プリント用シートの重ね合わせ状態説明図、図４は本発明の第二の構成例である、部分的に放射線硬化型接着剤の硬化層が施されてなる切り重ね感圧接着性プリント用シートの平面図、図５は図４のＸ−Ｘ線断面図、図６は図４の感圧接着性プリント用シートの重ね合わせ状態説明図、図７は本発明の第三の構成例である、重ね合わせ面全面に放射線硬化型接着剤の硬化層が施されてなる二つ折り感圧接着性プリント用シートの平面図、図８は図７のＸ−Ｘ線断面図、図９は図７の感圧接着性プリント用シートの重ね合わせ状態説明図、図１０は本発明の第四の構成例である、重ね合わせ面全面に放射線硬化型接着剤の硬化層が施されてなる三つ折り感圧接着性プリント用シートの平面図、図１１は図１０の感圧接着性プリント用シートの裏面図、図１２は図１０の感圧接着性プリント用シートの重ね合わせ状態説明図、図１３は本発明の第五の構成例である、再剥離接着性と永久接着性の放射線硬化型接着剤の硬化層が表裏それぞれの重ね合わせ面に施されてなる三つ折り感圧接着性プリント用シートの平面図、図１４は図１３の感圧接着性プリント用シートの裏面図、図１５は図１３の感圧接着性プリント用シートの重ね合わせ状態説明図、図１６は接着後の重ね合わせ面の各種剥離容易化手段の説明図、図１７はインキ被膜による放射線硬化型接着剤の硬化層の接着力調整方法を示す説明図である。
【００２２】
先ず、図１ないし図３に示す本発明の第一の構成例は、「三つ折り封書」として構成された、線状に放射線硬化型接着剤の硬化層４が施されてなる三つ折り感圧接着性プリント用シート１である。これは、基体シート２が二本の折り用ミシン線Ｍｆ，Ｍｆによって上紙片Ａ、中紙片Ｂ、下紙片Ｃに区画され、図３に示す如く、Ｚ字型に三つ折りに折り畳まれた状態で隠蔽情報を担持するものである。図１及び図２に示すように、基体シート２の表裏面に郵便番号記入欄、可変情報記入欄、説明文などの一般印刷５が施され、かつＺ字型に折り畳まれた際の重ね合わせ面３となるその周縁部に、折り畳まれた際に対接するようなパターンにて線状に放射線硬化型接着剤の硬化層４が施されている。なお、本構成例における放射線硬化型接着剤の硬化層４は永久接着性としても再剥離接着性としてもよく、再剥離接着性の場合は、図中における線状の該硬化層４に沿った切り用ミシン線は必要ない。
【００２３】
図４ないし図６に示す本発明の第二の構成例は「切り重ね伝票」として構成された、部分的に放射線硬化型接着剤の硬化層４が施されてなる切り重ね感圧接着性プリント用シート１である。これは、基体シート２が切り用ミシン線Ｍｃによって「納品書」たる上紙片Ａと「受領書」たる下紙片Ｃに区画され、図６に示す如く、二つ折りに折り畳まれた状態で隠蔽情報を担持するものである。そして、図４及び図５に示すように、基体シート２の表面に物品情報記入欄や社名などの一般印刷５が施されていると共に、折り畳まれた際の重ね合わせ面３、すなわち上紙片Ａの裏面と下紙片Ｃの表面に、折り畳まれた際に対接する短冊形態で放射線硬化型接着剤の硬化層４が施されている。なお、本構成例における放射線硬化型接着剤の硬化層４も永久接着性としても再剥離接着性としてもよく、再剥離接着性の場合は、図中における短冊形態の該硬化層４に沿った切り用ミシン線は必要ない。
【００２４】
図７ないし図９に示す本発明の第三の構成例は「隠蔽はがき」として構成された、重ね合わせ面３全面に放射線硬化型接着剤の硬化層４が施されてなる二つ折り感圧接着性プリント用シート１である。これは、基体シート２が折り用ミシン線Ｍｆによって上紙片Ａと下紙片Ｃに区画され、図９に示す如く、二つ折りに折り畳まれた状態で隠蔽情報を担持するものである。そして、図７及び図９に示すように、基体シート２の表裏面に郵便番号記入欄、購入品情報記入欄や社名などの一般印刷５が施され、かつ折り畳まれた際の重ね合わせ面３全面、すなわち、上紙片Ａと下紙片Ｃの片側面全面に放射線硬化型接着剤の硬化層４が施されている。なお、本構成例における放射線硬化型接着剤の硬化層４は再剥離接着性であるため、上紙片Ａの角部に切込みＫを設け、上紙片Ａと下紙片Ｂとの間に一部段差を生じさせ、接着後の重ね合わせ面の剥離を容易にしている。このような剥離容易化手段としては、図１６に示すように、本構成例におけるような（イ）重ね合わせ面の角部に切り込みＫを入れて段差を設けたり、（ロ）重ね合わせ面の辺部に切り込みＫを入れて段差を設けたり、（ハ）一方の重ね合わせ面にフラップ片Ｆを延設させて段差を設ける、などの手法が採用できる。
【００２５】
図１０ないし図１２に示す本発明の第四の構成例は「隠蔽はがき」として構成された、重ね合わせ面３全面に放射線硬化型接着剤の硬化層４が施されてなる三つ折り感圧接着性プリント用シート１である。これは、基体シート２が二本の折り用ミシン線Ｍｆ，Ｍｆによって上紙片Ａ、中紙片Ｂ、下紙片Ｃに区画され、図１２に示す如く、Ｚ字型に三つ折りに折り畳まれた状態で隠蔽情報を担持するものである。そして、図１０及び図１１に示すように、基体シート２の表裏面に郵便番号記入欄、可変情報記入欄、説明文などの一般印刷５が施され、かつＺ字型に折り畳まれた際の重ね合わせ面３全面に放射線硬化型接着剤の硬化層４が施されている。
【００２６】
図１３ないし図１４に示す本発明の第五の構成例は「隠蔽はがき」として構成された、永久接着性と再剥離接着性の放射線硬化型接着剤の硬化層４が表裏それぞれの重ね合わせ面４に施されてなる三つ折り用の感圧接着性プリント用シート１である。これは、基体シート２が二本の折り用ミシン線Ｍｆ，Ｍｆによって上紙片Ａ、中紙片Ｂ、下紙片Ｃに区画され、図１５に示す如く、Ｚ字型に三つ折りに折り畳まれた状態で隠蔽情報を担持するものである。そして、図１０及び図１２に示すように、基体シート２の表裏面に郵便番号記入欄、可変情報記入欄、説明文などの一般印刷５が施され、かつＺ字型に折り畳まれた際の、中紙片Ｂと下紙片Ｃの重ね合わせ面３全面に再剥離接着性の放射線硬化型接着剤の硬化層４が施され、その裏面側の上紙片Ａと中紙片Ｂの重ね合わせ面３全面に永久接着性の放射線硬化型接着剤の硬化層４が施されている。
【００２７】
本発明の感圧接着性プリント用シートは、このような永久接着部と再剥離接着部が同一基体シートに存在する構成も含むものであり、処方の異なる放射線硬化型接着剤を組み合わせたり、圧力の加減を部分的に変えるなどして永久接着部と再剥離接着部を現出させるものである。なお、放射線硬化型接着剤の硬化層の接着性の構成上の調整には、図１７に示すように、放射線硬化型接着剤の硬化層４に一部にインキ被膜６を設ける場合などもある。
【００２８】
【実施例】
次に実施例により本発明をさらに詳細に説明する。なお、各例における感圧接着性プリント用シートの接着性は以下の方法により評価した。
【００２９】
接着性；各例で得たシートを、幅２５ｍｍ、長さ１００ｍｍに裁断して試料を作成し、この試料２枚を２５ｍｍの長さで重ね合わせ、５０ｋｇ／ｃｍ²又は１００ｋｇ／ｃｍ²の荷重を加えて圧着したのち、オートグラフＡＧＳ５０（島津製作所製）を用いて剥離強度を測定し、以下の基準で評価した。
８０〜１２０ｇ／２５ｍｍ Ａ
５０〜８０ｇ／２５ｍｍ又は１２０〜１５０ｇ／２５ｍｍ Ｂ
３０〜５０ｇ／２５ｍｍ又は１５０〜１８０ｇ／２５ｍｍ Ｃ
３０ｇ／２５ｍｍ未満又は１８０ｇ／２５ｍｍ超過 Ｄ
【００３０】
実施例１
末端アクリル変性ポリブタジエン系プレポリマー（日本曹達株式会社製、製品名ＴＥＡ−１０００）６０重量部に光重合性モノマーとしてトリメチロールプロパンのプロピレンオキシド付加物（ｎ≒２）のトリアクリレート（東亜合成株式会社製、製品名Ｍ−３２０）４０重量部を加え、この混合物に対し５重量％の割合で光重合開始剤（日本チバガイギー社製、登録商標名「イルガキュア」５００）を添加した。
このようにして得た接着剤組成物を連量１１０ｋｇのコート紙に、ワイヤーバーにより１０ｇ／ｃｍ²の割合で塗布したのち、アイグラフフィクス（株）製紫外線照射装置を用いて露光処理し、硬化させた。このようにして無色透明で光沢のある接着剤層を有する感圧接着性プリント用シートを製造した。
このものの接着性を評価し、表１に示す。
【００３１】
【００３２】
【００３３】
【００３４】
実施例２
光重合性モノマーとして、トリメチロールプロパンのプロピレンオキシド付加物（ｎ≒２）のトリアクリレート（東亜合成株式会社製、製品名Ｍ−３２０）２０重量部と２‐エチルヘキシルカルビトールアクリレート（東亜合成株式会社製、製品名Ｍ−１２０）１５重量部と１，６‐ヘキサンジオールジアクリレート１５重量部との混合物を用いる以外は、実施例１と同様にして感圧接着性プリント用シートを製造した。
このものの接着性を評価し、その結果を表１に示す。
【００３５】
実施例３
プレポリマーとしてアクリル変性ウレタンプレポリマー（日本合成化学工業株式会社製、製品名ＵＶ−３０００Ｂ）６０重量部を用い、かつイソプロピルアルコール２０重量部で粘度調整すること以外は実施例１と同様にして感圧接着性プリント用シートを製造した。
このものの接着性を評価し、その結果を表１に示す。
【００３６】
【００３７】
【００３８】
【００３９】
【表１】

【００４０】
この表から、実施例１、２、３は、荷重５０ｋｇ／ｃｍ²で圧着した場合、また実施例３は荷重１００ｋｇ／ｃｍ²で圧着した場合はいずれも再剥離型感圧接着性プリント用シートとして使用可能であることが分る。
【００４１】
【発明の効果】
本発明の感圧接着性プリント用シートは、使用する放射線硬化型感圧接着剤の組成を適宜変えることにより、再剥離型及び完全接着型のいずれの形状にすることもできる。
また、この接着剤は、非水型であるため、乾燥により、しわを生じることがない上に、接着剤層は光沢を有し、外観も良好であり、しかもその上に印字可能であるという利点がある。
さらに、この接着剤層を形成する塗布工程を、印刷方式、コーティング方式の両方で行うことができるためプレスオンライン生産が可能になる。
【図面の簡単な説明】
【図１】 本発明の１例の三つ折り感圧接着性プリント用シートの平面図。
【図２】 図１の感圧接着性プリント用シートの裏面図。
【図３】 図１の感圧接着性プリント用シートの重ね合わせ状態説明図。
【図４】 本発明の図１とは別の例の切り重ね感圧接着性プリント用シートの平面図。
【図５】 図４のＸ−Ｘ線断面図。
【図６】 図４の感圧接着性プリント用シートの重ね合わせ状態説明図。
【図７】 本発明の図１及び図４とは別の例の重ね合わせ面全面に放射線硬化型接着剤の硬化層が施されてなる二つ折り感圧接着性プリント用シートの平面図。
【図８】 図７のＸ−Ｘ線断面図。
【図９】 図７の感圧接着性プリント用シートの重ね合わせ状態説明図。
【図１０】 本発明の図１、図４及び図７とは別の例の三つ折り感圧接着性プリント用シートの平面図。
【図１１】 図１０の感圧接着性プリント用シートの裏面図。
【図１２】 図１０の感圧接着性プリント用シートの重ね合わせ状態説明図。
【図１３】 本発明の図１、図４、図７及び図１０とは別の例の三つ折り感圧接着性プリント用シートの平面図。
【図１４】 図１３の感圧接着性プリント用シートの裏面図。
【図１５】 図１３の感圧接着性プリント用シートの重ね合わせ状態説明図。
【図１６】 接着後の重ね合わせ面の各種剥離容易化手段の説明図。
【図１７】 インキ被膜による放射線硬化型接着剤の硬化層の接着力調整法を示す説明図。
【符号の説明】
１ 感圧接着性プリント用シート
２ 基体シート
３ 重ね合わせ面
４ 放射線硬化型接着剤の硬化層
５ 一般印刷部分
Ａ 上紙片
Ｂ 中紙片
Ｃ 下紙片
Ｍｃ 切り用ミシン線
Ｍｆ 折り用ミシン線[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a folding sheet in which a surface overlapped by folding or cutting is used as an information carrying surface, a confidential information transmission sheet such as a superimposed sheet, an arrangement sheet whose dimensions can be expanded, a copy sheet, etc. The present invention relates to a pressure-sensitive adhesive printing sheet for bonding the overlapping surfaces with a special pressure-sensitive adhesive that has not been conventionally used in this type of printing sheet, such as an office sheet.
[0002]
[Prior art]
  Conventionally, in a print sheet that carries information on the overlapping surface, the entire overlapping surface is partially, in a pattern that usually comes into contact with the overlapping surface so that the overlapping surfaces adhere to each other, Alternatively, a hardened layer of pressure sensitive adhesive is linearly provided. This pressure-sensitive adhesive is also called a self-adhesive pressure-sensitive adhesive, and is a type in which each polymer is adhered by self-diffusion by applying a strong pressure with the cured layers in contact with each other. Depending on the type of composition and the degree of pressurization, permanent adhesiveness and re-peeling adhesiveness are realized.
[0003]
  Conventionally, the main component of pressure-sensitive adhesives used in this type of printing sheet is generally acrylic emulsion.ShiWater-based emulsions such as natural rubber latex and synthetic rubber latexShiIt contains an aqueous medium such as rubber or rubber latex. When such a pressure sensitive adhesive containing an aqueous medium is applied to a paper surface and dried for forming a cured layer thereof, a special dryer is required and work time is unavoidable. There are drawbacks such as paper deformation and loss of information carried.
[0004]
[Problems to be solved by the invention]
  The present invention overcomes the disadvantages of such pressure-sensitive adhesive printing sheets using conventional pressure-sensitive adhesives, shortens the work time during production, and causes troubles such as paper deformation. It was made for the purpose of obtaining a non-pressure-sensitive adhesive printing sheet.
[0005]
[Means for Solving the Problems]
  As a result of extensive research on pressure-sensitive adhesives suitable for pressure-sensitive adhesive printing sheets, the present inventors can easily apply and dry without using aqueous media when using radiation-curable adhesives. In addition, the present inventors have found that paper deformation can be suppressed, and based on this finding, the present invention has been made.
[0006]
  That is, the present invention relates to a radiation-curable pressure-sensitive adhesive that does not adhere to a predetermined portion of the overlapping surface of the base sheet in a normal state, but adheres by bringing the overlapping surfaces into contact with each other and applying a predetermined pressure. Pressure-sensitive adhesive printing sheet provided with a cured layerIn the radiation curable pressure-sensitive adhesive, a prepolymer having a terminal unsaturated group, a triacrylate or trimethacrylate of a propylene oxide adduct of trimethylolpropane, or a mixture of these with another photopolymerizable monomer, A pressure-sensitive adhesive printing sheet comprising a photosensitive composition containing a photopolymerization initiatorIs to provide.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
  The pressure-sensitive adhesive printing sheet of the present invention is formed by providing a required pressure-sensitive adhesive layer on the overlapping surface of the base sheet containing information. Arbitrary materials can be selected from materials conventionally used as substrates for pressure-sensitive adhesive printing sheets, such as coated paper, color lithographic paper, baryta paper, glossy paper, and various synthetic papers.
[0008]
  Next, as a radiation curable composition constituting the pressure-sensitive adhesive layer of the present invention,The endA photosensitive composition containing a prepolymer having an unsaturated group at the end, a photopolymerizable monomer, and a photopolymerization initiatorUsed.
  Examples of the unsaturated group bonded to the terminal of the prepolymer having an unsaturated group at the terminal include an acryloyl group, a methacryloyl group, an allyl group, and a methallyl group.
  Examples of the prepolymer having such an unsaturated group include an acrylic ester of epoxy resin, for example, diglycidyl ether diacrylate of bisphenol A, a reaction product of epoxy resin, acrylic acid and methyltetrahydrophthalic anhydride, epoxy Epoxy resin-based prepolymers such as the reaction product of resin and 2-hydroxyethyl acrylate, the reaction product of diglycidyl ether of epoxy resin and diallylamine, ring-opening copolymerization ester of glycidyl diacrylate and phthalic anhydride, Unsaturated polyester such as ester of methacrylic acid dimer and polyol, polyester obtained from acrylic acid, phthalic anhydride and propylene oxide, reaction product of polyethylene glycol, maleic anhydride and glycidyl methacrylate Prepolymers, polyvinyl alcohol and N-methylolacrylamide reaction products, polyvinyl alcohol prepolymers such as those obtained by esterifying polyvinyl alcohol with succinic anhydride and then added with glycidyl methacrylate, pyromellitic acid Polyamide-based prepolymer such as a prepolymer obtained by reacting an anhydride diallyl ester with p, p'-diaminodiphenyl, a reaction product of an ethylene-maleic anhydride copolymer and allylamine, methyl vinyl ether -A reaction product of maleic anhydride copolymer and 2-hydroxyethyl acrylate, or a polyacrylic acid or maleic acid copolymer prepolymer such as a product obtained by further reacting this with glycidyl methacrylate is used.
[0009]
  In addition, a urethane-based prepolymer having a polyoxyalkylene segment or a saturated polyester segment or both linked via a urethane bond and having an acryloyl group or a methacryloyl group at both ends, or a general formula
[Chemical 1]

  (Wherein R is a formula
[Chemical 2]

And n is a number indicating the degree of polymerization)
A rubber-based prepolymer such as terminal acrylic-modified isoprene rubber or butadiene rubber represented by the formula is also a preferred prepolymer.
[0010]
  These prepolymers suitably have a weight average molecular weight in the range of 2000 to 30000. When using a material having a molecular weight smaller than this, it is difficult to handle because it causes a large amount of tackiness and blocking, and when a material having a molecular weight larger than this is used, pressure-sensitive adhesiveness after curing is lowered. Since it becomes difficult to peel off after bonding once, it cannot be used for removable bonding.
[0011]
  Next, as a photopolymerizable monomer used in combination with a prepolymer having a terminal unsaturated group,It is necessary to use a triacrylate or trimethacrylate of a trimethylolpropane propylene oxide adduct or a mixture thereof with other photopolymerizable monomers.
  The triacrylate of the propylene oxide adduct of trimethylolpropane is known and is commercially available, for example, from Toa Gosei Co., Ltd. under the product name “M-120”.
  In some cases, the other photopolymerizable monomer used in admixture with the triacrylate or trimethacrylate of the propylene oxide adduct of trimethylolpropane can be arbitrarily selected from the compounds usually used as photopolymerizable monomers. it can.
  like thisCompoundFor example, unsaturated carboxylic acids such as acrylic acid and methacrylic acid or esters thereof such as alkyl-, cycloalkyl-, halogenated alkyl-, alkoxyalkyl-, hydroxyalkyl-, aminoalkyl-, tetrahydrofurfuryl-, allyl -, Glycidyl-, benzyl-, phenoxy-acrylate and methacrylate, alkylene glycol, polyoxyalkylene glycol mono- or diacrylate and methacrylate, trimethylolpropane triacrylate and methacrylate, pentaerythritol tetraacrylate and methacrylate, acrylamide, methacrylamide Or derivatives thereof such as acrylamide and methacrylamide mono- or di-substituted with alkyl or hydroxyalkyl groups Allyl compounds such as diacetone acrylamide and methacrylamide, N, N′-alkylenebisacrylamide and methacrylamide, such as allyl alcohol, allyl isocyanate, diallyl phthalate, triallyl isocyanurate, maleic acid, maleic anhydride, fumaric acid or the like Other unsaturated compounds such as esters such as alkyl, halogenated alkyl, alkoxyalkyl mono or dimaleates and fumarate such as styrene, vinyl toluene, divinyl benzene, N-vinyl carbazole, N-vinyl pyrrolidone and the like are used.
[0012]
  In the case where the curing shrinkage is hindered, examples of the monomer include isobornyl acrylate or methacrylate, norbornyl acrylate or methacrylate, dicyclopentenoxyethyl acrylate or methacrylate, dicyclopentenoxypropyl acrylate. Or methacrylates such as diethylene glycol dicyclopentenyl monoether acrylate or methacrylate, polyoxyethylene or polypropylene glycol dicyclopentenyl monoether acrylate or methacrylate, dicyclopentenyl cinnamate, dicyclopenteno 3,9-bis (1,1-bismethane) such as xylethylcinnamate, dicyclopentenoxyethyl monofumarate or difumarate Lu-2-oxyethyl) -spiro [5,5] undecane, 3,9-bis (1,1-bismethyl-2-oxyethyl) -2,4,8,10-tetraoxaspiro [5,5] undecane, Mono, such as 3,9-bis (2-oxyethyl) -spiro [5,5] undecane, 3,9-bis (2-oxyethyl) -2,4,8,10-tetraoxaspiro [5,5] undecane -, Diacrylate or mono-, dimethacrylate, or mono-, diacrylate, or mono-, dimethacrylate of these spiroglycol or ethylene oxide or propylene oxide addition polymers, or methyl ether of the monoacrylate or methacrylate, 1-azabicyclo [2,2,2] -3-octenyl acrylate or methacrylate, bisic [2,2,1] -5-heptene-2,3-dicarboxyl monoallyl ester, such as dicyclopentadienyl acrylate or methacrylate, dicyclopentadienyloxyethyl acrylate or methacrylate, dihydrodicyclopentadienyl acrylate Alternatively, methacrylate can be used.
  These photopolymerizable monomers are singleOrCombine two or moreCan be used.The amount to be used is selected within the range of 2 times or less, preferably 0.5 to 1.5 times, based on the weight of the prepolymer having a terminal unsaturated group.
[0013]
  Moreover, as a photoinitiator used with the said prepolymer and a photopolymerizable monomer, arbitrary things can be selected from the well-known photoinitiators in a normal photosensitive resin composition, and can be used. Examples of such photopolymerization initiators include benzoin alkyl ethers such as benzoin, benzoin ethyl ether, benzoin-n-propyl ether, benzoin-isopropyl ether, and benzoin isobutyl ether, and 2,2-dimethoxy-2-phenylacetophenone. Benzophenone, benzyl, diacetyl, diphenyl sulfide, eosin, thionine, 9,10-anthraquinone, 2-ethyl-9,10-anthraquinone, and the like.
  These photopolymerization initiators may be used alone or in combination of two or more. The content is usually selected in the range of 0.1 to 10 parts by weight per 100 parts by weight of the total amount of the prepolymer and the photopolymerizable monomer.
[0014]
  The radiation-curing pressure-sensitive adhesive used in the present invention includes a fine particle filler for suppressing the occurrence of difficulty in peeling due to an increase in adhesive force over time after being overlapped, or to prevent blocking, if desired. Can be contained. As such a fine particle filler, one having a small affinity with the above-mentioned three components and having a particle shape regularly arranged should be used so that the adhesive layer does not hinder the transparency. Good. Examples of such materials include various starch series, synthetic zeolite, fine spherical acrylic resin, fine spherical methacrylic resin, fine spherical polyethylene, spherical alumina, glass powder, shirasu balloon, activated clay, and the like. These fillers may be used alone or in combination of two or more. However, silica, titanium oxide, zinc oxide, etc., which are conventionally used as fillers in this type of adhesive composition, are irregular in their particle shape, and thus promote the diffuse reflection of light on the adhesive layer, making it transparent. However, when these are added, the addition amount is preferably 10% by weight or less. These fine particle fillers have an average particle diameter of 1 to 20 μm, preferably 2 to 5 μm.
[0015]
  When the fine particle filler is contained, it is necessary to appropriately select the blending ratio. If the compounding amount of the fine particle filler is too small, the anti-blocking property is lowered, or the adhesive strength is too strong to be peeled off, and if it is too large, the adhesive strength is too low and sufficient tackiness is obtained. Not shown. Therefore, the mixing ratio of the fine particle filler is 100 to 300 parts by weight, preferably 130 to 250 parts by weight, more preferably 150 to 200 parts by weight, based on 100 parts by weight of the radiation curable pressure-sensitive adhesive. It is better to select it within the range of parts by weight.
[0016]
  In addition to the four components described above, the photosensitive composition constituting the radiation curable pressure-sensitive adhesive layer in the present invention may further contain additive components commonly used in general photosensitive resin compositions as desired, for example, Thermal polymerization inhibitors, tackifiers, viscosity modifiers, anti-aging agents, stabilizers, colorants, fine particle fillers, and the like can be included. Examples of the thermal polymerization inhibitor include hydroquinone, mono-tert-butylhydroquinone, benzoquinone, 2,5-diphenyl-p-benzoquinone, picric acid, di-p-fluorophenylamine, di-p-methoxyphenol, 2,6 -Di-tert-butyl-p-cresol and the like. These thermal polymerization inhibitors are for preventing thermal polymerization reaction, and therefore the content of the thermal polymerization inhibitor is usually in the range of 0.01 to 5 parts by weight per 100 parts by weight of the resin base. Chosen by
[0017]
  The pressure-sensitive adhesive printing sheet of the present invention can be produced, for example, as follows.
  That is, the above-mentioned radiation is applied to a predetermined base sheet by applying means such as a gravure coater, a flexo, an air knife coater, a bar coater, or the like on a part facing the base sheet by bi-folding, tri-folding, stacking, or overlapping each other. A curable pressure sensitive adhesive is applied and then dried to form an adhesive layer. Application | coating in this case may be performed over the whole surface of a base sheet, and may be performed only on the surface of a part. Necessary information may be printed on the surface of the base sheet in advance, or information may be printed after an adhesive layer is applied. At this time, when printing information using a commonly used printing press using UV curable ink for printing, it should be performed at the same time as the printing process and the application and fixing of the radiation curable pressure sensitive adhesive. This is advantageous.
[0018]
  In the present invention, when a synthetic film such as polyethylene, polypropylene, polyethylene terephthalate, or polyvinyl chloride is used as the substrate sheet, the surface of the substrate sheet is preferably subjected to surface treatment such as mat treatment or corona treatment. The amount of the adhesive applied to the base sheet surface is 1 to 30 g / m in order to maintain the adhesiveness, peelability or transparency of the adhesive layer.², Preferably 3-20 g / m², More preferably 5 to 15 g / m²It is chosen to be within the range.
[0019]
  The pressure-sensitive adhesive printing sheet produced in this way is irradiated with radiation such as ultraviolet rays, electron beams, X-rays, i-rays, g-rays, etc., and the adhesive layer is appropriately cured, and then each side. Of the cured adhesive layer, for example, about 1 to 100 kg / cm by a pressure roller.²Adhere under pressure of.
[0020]
  The permanent adhesion and re-peeling adhesion of the cured layer of the radiation curable pressure-sensitive adhesive in the present invention are the types of prepolymer and photopolymerizable monomer having an unsaturated group at the terminal, the use ratio of both, and photopolymerizability. It can be adjusted by changing the number of functional groups of the monomer, the roller pressure at the time of adhesion, and the like. In general, the more functional groups of the photopolymerizable monomer, the harder the adhesion surface and the lower the adhesion force, and the greater the roller pressure during adhesion, the greater the adhesion force.
[0021]
  Next, although the structural example of the pressure-sensitive-adhesive printing sheet of this invention is demonstrated in detail according to an accompanying drawing, this invention is not limited by these structural examples. Here, FIG. 1 is a plan view of a tri-fold pressure-sensitive adhesive printing sheet in which a cured layer of a radiation curable adhesive is linearly applied, which is a first configuration example of the present invention, FIG. 1 is a rear view of the pressure-sensitive adhesive printing sheet of FIG. 1, FIG. 3 is an explanatory diagram of the superimposed state of the pressure-sensitive adhesive printing sheet of FIG. 1, and FIG. 4 is a second configuration example of the present invention. FIG. 5 is a cross-sectional view taken along the line XX of FIG. 4 and FIG. 6 is a pressure-sensitive adhesive of FIG. 4. FIG. 7 shows a third example of the structure of the present invention. FIG. 7 illustrates a third example of the present invention. The folded folded pressure-sensitive adhesive print has a cured layer of a radiation curable adhesive on the entire overlapping surface. FIG. 8 is a cross-sectional view taken along line XX of FIG. 7, and FIG. 9 is for pressure-sensitive adhesive printing of FIG. FIG. 10 is a fourth configuration example of the present invention. FIG. 10 is a three-fold pressure-sensitive adhesive printing sheet in which a cured layer of a radiation curable adhesive is applied to the entire overlapping surface. 11 is a back view of the pressure-sensitive adhesive printing sheet of FIG. 10, FIG. 12 is an explanatory diagram of the superimposed state of the pressure-sensitive adhesive printing sheet of FIG. 10, and FIG. 13 is a fifth view of the present invention. FIG. 14 is a plan view of a tri-fold pressure-sensitive adhesive printing sheet in which a cured layer of a re-peeling adhesive and permanent adhesive radiation-curing adhesive, which is a structural example, is applied to the front and back overlapping surfaces, FIG. 15 is a back view of the pressure-sensitive adhesive printing sheet of FIG. 13, FIG. 15 is an explanatory diagram of the overlapping state of the pressure-sensitive adhesive printing sheet of FIG. 13, and FIG. Explanatory drawing, Fig. 17 shows radiation by ink coating Is an explanatory view showing the adhesive force adjusting method of the hardened layer of the reduction-type adhesive.
[0022]
  First, the first configuration example of the present invention shown in FIG. 1 to FIG. 3 is a tri-fold pressure sensitivity in which a cured layer 4 of a radiation curable adhesive is applied in a linear form, which is configured as a “three-fold sealed letter”. This is an adhesive printing sheet 1. This is a state in which the base sheet 2 is divided into an upper paper piece A, an intermediate paper piece B, and a lower paper piece C by two folding sewing lines Mf and Mf, and is folded in a Z-shape as shown in FIG. It carries concealment information. As shown in FIG. 1 and FIG. 2, general printing 5 such as a postal code entry field, a variable information entry field, an explanatory note, etc. is applied to the front and back surfaces of the base sheet 2 and is overlapped when folded into a Z-shape. A cured layer 4 of a radiation curable adhesive is linearly applied to the peripheral portion of the surface 3 in a pattern that makes contact when folded. In addition, the cured layer 4 of the radiation curable adhesive in the present configuration example may be permanent adhesive or re-peelable adhesive. In the case of re-peelable adhesive, the cured layer 4 along the linear cured layer 4 in the drawing is used. No cutting machine line is required.
[0023]
  The second structural example of the present invention shown in FIG. 4 to FIG. 6 is a “ply-out slip”, which is a cut-up pressure-sensitive adhesive print partially formed with a cured layer 4 of radiation-curable adhesive. Sheet 1 for use. This is because the base sheet 2 is divided into an upper paper piece A as a “delivery note” and a lower paper piece C as a “receipt” by a cutting machine line Mc, and the concealment information is folded in two as shown in FIG. Is supported. As shown in FIGS. 4 and 5, the surface of the base sheet 2 is provided with general printing 5 such as an article information entry column and a company name, and the overlapping surface 3 when folded, that is, the upper paper piece A A cured layer 4 of a radiation curable adhesive is applied to the back surface of the sheet and the surface of the lower paper piece C in the form of a strip that comes into contact when folded. In addition, the cured layer 4 of the radiation curable adhesive in this configuration example may be either permanent adhesive or re-peelable adhesive, and in the case of the re-peelable adhesive, the strip-shaped cured layer 4 in the drawing is aligned. No cutting machine line is required.
[0024]
  The third structural example of the present invention shown in FIGS. 7 to 9 is a two-fold pressure-sensitive adhesive constructed as a concealing postcard and having a cured layer 4 of a radiation curable adhesive applied to the entire overlapping surface 3. 1 is a sheet 1 for printability. In this case, the base sheet 2 is divided into an upper paper piece A and a lower paper piece C by a folding sewing line Mf, and carries concealment information in a folded state as shown in FIG. Then, as shown in FIG. 7 and FIG. 9, general printing 5 such as a postal code entry field, a purchased product information entry field, a company name, etc. is applied to the front and back surfaces of the base sheet 2, and the overlapping surface 3 when folded. A cured layer 4 of radiation curable adhesive is applied to the entire surface, that is, the entire one side surface of the upper paper piece A and the lower paper piece C. In addition, since the cured layer 4 of the radiation curable adhesive in this configuration example has re-peeling adhesiveness, a notch K is provided at the corner of the upper paper piece A, and a part of the level difference is formed between the upper paper piece A and the lower paper piece B. This makes it easy to peel off the overlapped surface after bonding. As such a peeling facilitating means, as shown in FIG. 16, (b) a step is formed by making a cut K in the corner of the overlapping surface as in this configuration example, or (b) the overlapping surface It is possible to employ a technique such as providing a step by making a cut K on the side, or (c) providing a step by extending the flap piece F on one overlapping surface.
[0025]
  A fourth configuration example of the present invention shown in FIGS. 10 to 12 is a tri-fold pressure-sensitive adhesive, which is configured as a “concealing postcard”, and a cured layer 4 of a radiation curable adhesive is applied to the entire overlapping surface 3. 1 is a sheet 1 for printability. This is a state in which the base sheet 2 is divided into an upper paper piece A, an intermediate paper piece B, and a lower paper piece C by two folding sewing lines Mf and Mf, and is folded in a Z-shape in three as shown in FIG. It carries concealment information. Then, as shown in FIG. 10 and FIG. 11, when the front and back surfaces of the base sheet 2 are subjected to general printing 5 such as a postal code entry field, a variable information entry field, an explanatory note, etc., and when folded into a Z-shape A cured layer 4 of a radiation curable adhesive is applied to the entire overlapping surface 3.
[0026]
  The fifth structural example of the present invention shown in FIGS. 13 to 14 is a concealment layer 4 of a radiation curable adhesive of permanent adhesiveness and re-peeling adhesive, which is configured as a “hiding postcard”. 4 is a three-fold pressure-sensitive adhesive printing sheet 1. This is because the base sheet 2 is divided into an upper paper piece A, an intermediate paper piece B, and a lower paper piece C by two folding sewing lines Mf and Mf, and is folded in a Z-shape in three as shown in FIG. It carries concealment information. Then, as shown in FIG. 10 and FIG. 12, when the general printing 5 such as a postal code entry field, a variable information entry field, an explanatory text, etc. is applied to the front and back surfaces of the base sheet 2, and when folded into a Z-shape Then, a cured layer 4 of a releasable adhesive radiation curable adhesive is applied to the entire overlapping surface 3 of the middle paper piece B and the lower paper piece C, and the entire overlapping surface 3 of the upper paper piece A and the middle paper piece B on the back side thereof. Further, a hardened layer 4 of a permanent adhesive radiation curable adhesive is applied.
[0027]
  The pressure-sensitive adhesive printing sheet of the present invention includes a configuration in which such a permanent adhesive portion and a re-peeling adhesive portion are present in the same base sheet, and can be combined with radiation curable adhesives having different formulations, For example, the permanent adhesion portion and the re-peeling adhesion portion are made to appear by partially changing the amount of adjustment. In addition, as shown in FIG. 17, the adjustment of the adhesive property of the cured layer of the radiation curable adhesive may be partially provided with an ink film 6 on the cured layer 4 of the radiation curable adhesive. .
[0028]
【Example】
  Next, the present invention will be described in more detail with reference to examples. In addition, the adhesiveness of the pressure-sensitive adhesive printing sheet in each example was evaluated by the following method.
[0029]
  Adhesiveness: The sheet obtained in each example was cut to a width of 25 mm and a length of 100 mm to prepare a sample, and the two samples were overlapped to a length of 25 mm, and 50 kg / cm²Or 100 kg / cm²After applying the above load and pressure bonding, the peel strength was measured using an autograph AGS50 (manufactured by Shimadzu Corporation) and evaluated according to the following criteria.
  80-120g / 25mm A
  50-80g / 25mm or 120-150g / 25mm B
  30-50g / 25mm or 150-180g / 25mm C
  Less than 30g / 25mm or more than 180g / 25mm D
[0030]
Example 1
  Trimethylol as a photopolymerizable monomer in 60 parts by weight of a terminal acrylic-modified polybutadiene-based prepolymer (manufactured by Nippon Soda Co., Ltd., product name TEA-1000)propane40 parts by weight of a propylene oxide adduct (n≈2) of triacrylate (product name M-320, manufactured by Toagosei Co., Ltd.) was added, and a photopolymerization initiator (Nippon Ciba Geigy Co., Ltd.) at a ratio of 5% by weight to this mixture. Manufactured trade name “Irgacure” 500).
  The adhesive composition thus obtained was applied to a coated paper having a continuous weight of 110 kg, and 10 g / cm by a wire bar.²After being applied at the ratio, the film was exposed to light and cured using an ultraviolet irradiation device manufactured by IGRAPHFIX Co., Ltd. In this way, a pressure-sensitive adhesive printing sheet having a colorless, transparent and glossy adhesive layer was produced.
  The adhesive properties of this product were evaluated and are shown in Table 1.
[0031]
[0032]
[0033]
[0034]
Example2
  Trimethylol as a photopolymerizable monomerpropane20 parts by weight of a propylene oxide adduct (n≈2) (product name M-320, manufactured by Toa Gosei Co., Ltd.) and 2-ethylhexyl carbitol acrylate (product name M-120, manufactured by Toa Gosei Co., Ltd.) 15 Examples are used except that a mixture of parts by weight and 15 parts by weight of 1,6-hexanediol diacrylate is used.1In the same manner, a pressure-sensitive adhesive printing sheet was produced.
  The adhesiveness of this product was evaluated, and the results are shown in Table 1.
[0035]
Example3
  Sensitive in the same manner as in Example 1 except that 60 parts by weight of an acrylic-modified urethane prepolymer (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., product name UV-3000B) is used as the prepolymer and the viscosity is adjusted with 20 parts by weight of isopropyl alcohol. A pressure-sensitive adhesive printing sheet was produced.
  The adhesiveness of this product was evaluated, and the results are shown in Table 1.
[0036]
[0037]
[0038]
[0039]
[Table 1]

[0040]
  From this table, examples1, 2, 3, Load 50kg / cm²Crimped withAnd also Example 3Load 100kg / cm²Crimped withCaseCan be used as re-peelable pressure-sensitive adhesive printing sheetsAhI understand that.
[0041]
【The invention's effect】
  The pressure-sensitive adhesive printing sheet of the present invention can be made into either a re-peelable type or a fully-adhesive type by appropriately changing the composition of the radiation-curable pressure-sensitive adhesive used.
  In addition, since this adhesive is non-aqueous, it does not cause wrinkles due to drying, and the adhesive layer has a gloss, good appearance, and can be printed thereon. There are advantages.
  Furthermore, since the coating process for forming the adhesive layer can be performed by both a printing method and a coating method, press on-line production becomes possible.
[Brief description of the drawings]
FIG. 1 is a plan view of a tri-fold pressure-sensitive adhesive printing sheet according to an example of the present invention.
2 is a rear view of the pressure-sensitive adhesive printing sheet of FIG. 1. FIG.
FIG. 3 is an explanatory diagram of a superposition state of the pressure-sensitive adhesive printing sheet of FIG.
4 is a plan view of a pressure-sensitive adhesive print sheet according to another example of the present invention different from FIG. 1. FIG.
5 is a cross-sectional view taken along line XX in FIG.
FIG. 6 is an explanatory diagram of a superposition state of the pressure-sensitive adhesive printing sheet of FIG.
7 is a plan view of a two-fold pressure-sensitive adhesive printing sheet in which a cured layer of a radiation curable adhesive is applied to the entire overlapping surface of an example different from FIGS. 1 and 4 of the present invention. FIG.
8 is a cross-sectional view taken along line XX in FIG.
FIG. 9 is an explanatory diagram of a superposition state of the pressure-sensitive adhesive printing sheet of FIG.
FIG. 10 is a plan view of a tri-fold pressure-sensitive adhesive printing sheet of an example different from FIGS. 1, 4 and 7 of the present invention.
11 is a rear view of the pressure-sensitive adhesive printing sheet of FIG.
FIG. 12 is an explanatory diagram of an overlapping state of the pressure-sensitive adhesive printing sheet of FIG.
13 is a plan view of a tri-fold pressure-sensitive adhesive printing sheet of another example different from FIGS. 1, 4, 7 and 10 of the present invention. FIG.
14 is a rear view of the pressure-sensitive adhesive printing sheet of FIG.
FIG. 15 is an explanatory diagram of a superposition state of the pressure-sensitive adhesive printing sheet of FIG.
FIG. 16 is an explanatory diagram of various means for facilitating peeling of the overlapped surface after bonding.
FIG. 17 is an explanatory diagram showing a method for adjusting the adhesive strength of a cured layer of a radiation curable adhesive using an ink film.
[Explanation of symbols]
  1 Pressure-sensitive adhesive printing sheet
  2 Base sheet
  3 Overlapping surface
  4 Hardened layer of radiation curable adhesive
  5 General printing part
  A Top piece of paper
  B Medium paper piece
  C Lower strip
  Mc cutting machine wire
  Mf folding machine wire

Claims (2)

A predetermined layer of the overlapping surface of the base sheet is provided with a cured layer of a radiation curable pressure-sensitive adhesive that does not adhere in a normal state but adheres by bringing the overlapping surfaces into contact with each other and applying a predetermined pressure. In the pressure-sensitive adhesive printing sheet , as the radiation-curable pressure-sensitive adhesive, a prepolymer having a terminal unsaturated group, a triacrylate or trimethacrylate of a propylene oxide adduct of trimethylolpropane, or other photopolymerization thereof. A pressure-sensitive adhesive printing sheet comprising a photosensitive composition containing a mixture of a photopolymerizable monomer and a photopolymerization initiator. Pressure-sensitive adhesive printing sheet of claim 1 wherein said radiation-curable pressure-sensitive adhesive contains a particulate filler having an average particle particle 1 to 20 [mu] m.

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