JP2004093591A - Photosensitive composition, planographic printing plate, method for processing planographic printing plate and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive composition and a planographic printing plate having high sensitivity and excellent printing durability, storage stability, stain-proofing property and yielding a reduced amount of sludge, and to provide a method for processing the planographic printing plate and an image forming method. <P>SOLUTION: The photosensitive composition comprises a borate compound represented by formula (1), a cationic dye and a compound having an ethylenically unsaturated group, wherein 10 to 90 mass% of the compound having an ethylenically unsaturated group has a weight average molecular weight of 15,000 to 200,000 and an acid value of 30 to 200 mg/KOH. In a combination with a tertiary amine monomer being a preferred implementation of this invention, sensitivity, storage stability and printing durability are remarkably improved. <P>COPYRIGHT: (C)2004,JPO

Description

【００９７】
【化８】

【００９８】
【化９】

【００９９】
次に、本発明に好ましく用いられる前記一般式（３）で表されるエチレン性二重結合含有単量体について説明する。
【０１００】
前記一般式（３）において、Ｒ^８は（ｇ−ｆ）が２以上の場合は、互いに異なってもよい。ｇとｆが同じ値である化合物が好ましい。Ｒ^８がアルキル基、ヒドロキシアルキル基の場合は、炭素数２〜８が好ましく、２〜４がより好ましい。Ｒ^８がアリール基の場合は、単環または２環が好ましく、単環がより好ましく、かつ炭素数５個までのアルキル基、アルコキシアルキル基またはハロゲン原子で置換されてもよい。
【０１０１】
Ｒ^５及びＲ^６がアルキル基またはアルコキシアルキル基の場合は、炭素数１〜５が好ましい。
【０１０２】
Ｒ^７はメチル基が好ましい。
Ｄ^３及びＤ^４は同一または異なってもよく、かつ２個の窒素原子を含む６員の飽和複素環が好ましい。
【０１０３】
Ｆが飽和炭化水素基の場合は２〜６個の炭素原子を有することが好ましく、Ｆがアリーレン基の場合はフェニレン基が好ましく、環状脂肪族基の場合はシクロヘキシレン基が好ましく、複素環芳香族基の場合は窒素原子または硫黄原子を含む５〜６員環が好ましい。
【０１０４】
一般式（３）で表される化合物を得るには、Ｑ^２がＮであり、ｎとｍが同じ値の場合は、グリシジルアクリレートまたはアルキルアクリレートをヒドロキシアルキルアミンと反応させる。他の化合物も同様にして得ることができる。
【０１０５】
本発明の一般式（３）で表される化合物の具体例を以下に示す。
【０１０６】
【化１０】

【０１０７】
本発明の感光性平版印刷版材料及び本発明の画像形成方法で用いる感光性平版印刷版材料の光重合性感光層には、上記したエチレン性不飽和基を含有する化合物を総量として、５〜９９質量％の範囲で含有することが好ましく、１０〜９８質量％の範囲がより好ましく、２０〜９７質量％の範囲が特に好ましい。
【０１０８】
（ホウ素塩化合物）
有機系ボレート塩化合物としては、特開昭６２−１４３０４４号、特開平９−１８８６８５号、同９−１８８６８６号、同９−１８８７１０号等に記載の有機ボレート化合物（以下、「ボレート化合物」という場合がある。）、又はカチオン性色素から得られる分光増感色素系ボレート化合物等が挙げられる。本発明の一般式（１）で示される化合物の具体例を以下に挙げるが、本発明はこれらに限定されるものではない。
【０１０９】
【化１１】

【０１１０】
【化１２】

【０１１１】
【化１３】

【０１１２】
【化１４】

【０１１３】
【化１５】

【０１１４】
【化１６】

【０１１５】
【化１７】

【０１１６】
本発明では、特に嵩高い置換基を有するホウ素塩が好ましい。
本明細書において使用される「嵩高い置換基」という用語は、例えば、多環、すなわち多環式アリール基、または単なる置換されたアリール基を意味する。これらの例は異原子、好ましくはＳ、ＯまたはＮを含むか、または含まない縮合された炭化水素環であり、その例は１−および２−ナフチル基、ビナフチル基、アントラシル基、フェナントリル基、ピレニル基、キノリル基およびイソキノリル基である。しかしながら、「嵩高い置換基」という用語は環配列、すなわち単結合で結合されたアリール環をも意味する。これらの例はビフェニル基、ｏ−、ｍ−またはｐ−ターフェニル基またはトリフェニルフェニル基である。
【０１１７】
炭素原子数１ないし２０のアルキル基は線状または枝分かれ基であり、例えば炭素原子数１ないし１２のアルキル基、炭素原子数１ないし８のアルキル基、炭素原子数１ないし６のアルキル基または炭素原子数１ないし４のアルキル基である。例えばメチル基、エチル基、プロピル基、イソプロピル基、ｎ−ブチル基、第二−ブチル基、イソ−ブチル基、第三−ブチル基、ペンチル基、ヘキシル基、ヘプチル基、２，４，４−トリメチル−フェニル基、２−エチルヘキシル基、オクチル基、ノニル基、デシル基、ウンデシル基、ドデシル基、テトラデシル基、ペンタデシル基、ヘキサデシル基、ヘプタデシル基、オクタデシル基、ノナデシル基またはエイコシル基である。
【０１１８】
−Ｏ−、−Ｓ（Ｏ）ｐ−または−ＮＲ_５−で１回またはそれよりも多く中断された炭素原子数２ないし２０のアルキル基は、例えば１ないし９回、例えば１ないし７回または１回もしくは２回、−Ｏ−、−Ｓ（Ｏ）ｐ−または−ＮＲ_５−で中断されている。（Ｒ_５は水素原子、炭素原子数１〜１２のアルキル基、フェニル−炭素原子数１〜６のアルキル基またはフェニル基を表し、上記フェニル−炭素原子数１〜６のアルキル基またはフェニル基は置換されていないか、または炭素原子数１〜６のアルキル基、炭素原子数１〜１２のアルコキシ基またはハロゲン原子により１〜５回置換されている基を表す。）これにより、例えば以下のような構造単位：−ＣＨ_２−Ｏ−ＣＨ_３、−ＣＨ_２ＣＨ_２−Ｏ−ＣＨ_２ＣＨ_３、−［ＣＨ_２ＣＨ_２Ｏ］ｙ−ＣＨ_３（式中、ｙは１ないし９を表す）、−（ＣＨ_２ＣＨ_２Ｏ）_７ＣＨ_２ＣＨ_３、−ＣＨ_２−ＣＨ（ＣＨ_３）−Ｏ−ＣＨ_２ＣＨ_２ＣＨ_３、−ＣＨ_２−ＣＨ（ＣＨ_３）−Ｏ−ＣＨ_２ＣＨ_２、−ＣＨ_２ＳＣＨ_３または−ＣＨ_２−Ｎ（ＣＨ_３）_２を形成する。
【０１１９】
炭素原子数３ないし１２のシクロアルキル基は、例えばシクロプロピル基、シクロペンチル基、シクロヘキシル基、シクロオクチル基、シクロドデシル基、特にシクロペンチル基およびシクロヘキシル基、好ましくはシクロヘキシル基である。１ないし多置換され得る炭素原子数２ないし８のアルケニル基は、例えばアリル基、メタリル基、１，１−ジメチルアリル基、１−ブテニル基、３−ブテニル基、２−ブテニル基、１，３−ペンタジエニル基、５−ヘキセニル基または７−オクテニル基、特にアリル基である。炭素原子数２ないし８のアルケニル基としてのＲ_４は、例えば炭素原子数２ないし６のアルケニル基、特に炭素原子数２ないし４のアルケニル基である。
【０１２０】
フェニル−炭素原子数１ないし６のアルキル基は、例えばベンジル基、フェニルエチル基、α−メチルベンジル基、フェニルペンチル基、フェニルヘキシル基またはα、α−ジメチルベンジル基、特にベンジル基である。好ましいものは、フェニル−炭素原子数１ないし４のアルキル基、特にフェニル−炭素原子数１または２のアルキル基である。置換されたフェニル−炭素原子数１ないし６のアルキル基は１ないし４回、例えば１回、２回または３回、特に１回または２回フェニル環上で置換されている。
【０１２１】
フェニル−炭素原子数１ないし６のアルキレン基は２つの遊離結合を有し、その一方はフェニル環上にあり、そして他方はアルキレン基にある。すなわち次式
【０１２２】
【化１８】

【０１２３】
（式中、ｘは１ないし６を表す）で表される。
置換されたフェニル基は１ないし５回、例えば１回、２回または３回、特に１回または２回フェニル環上で置換されている。置換基は例えばフェニル環の２位と６位、２位と４位または２位、４位および６位にあり、好ましくは２位と６位または２位、４位および６位にある。ナフチル−炭素原子数１ないし３のアルキル基は、例えばナフチルメチル基、ナフチルエチル基、ナフチルプロピル基またはナフチル−１−メチルエチル基、特にナフチルメチル基である。アルキル単位はナフチル環系の１位または２位のいずれかに有り得る。置換されたナフチル−炭素原子数１ないし３のアルキル基は１ないし４回、例えば１回、２回または３回、特に１回または２回芳香環上で置換されている。
【０１２４】
炭素原子数１ないし１２のアルコキシ基は線状または枝分かれ基であり、例えばメトキシ基、エトキシ基、プロポキシ基、イソプロポキシ基、ｎ−ブチルオキシ基、第二ブチルオキシ基、イソブチルオキシ基、第三ブチルオキシ基、ペンチルオキシ基、ヘキシルオキシ基、ヘプチルオキシ基、２，４，４−トリメチルペンチルオキシ基、２−エチルヘキシルオキシ基、オクチルオキシ基、ノニルオキシ基、デシルオキシ基またはドデシルオキシ基、特にメトキシ基、エトキシ基、プロポキシ基、イソプロポキシ基、ｎ−ブチルオキシ基、第二ブチルオキシ基、イソブチルオキシ基、第三ブチルオキシ基、好ましくはメトキシ基である。
【０１２５】
ハロゲン原子はフッ素原子、塩素原子、臭素原子およびヨウ素原子、特に塩素原子、臭素原子およびフッ素原子、好ましくは塩素原子およびフッ素原子である。１またはそれ以上のハロゲン原子で置換された炭素原子数１ないし２０のアルキル基は、例えばアルキル基上で１ないし３または１もしくは２個のハロゲン置換基により置換されている。
【０１２６】
２価の芳香族炭化水素基の例はフェニレン基、スチルベニレン基、ビフェニレン基、ｏ−、ｍ−またはｐ−ターフェニレン基、トリフェニルフェニレン基、ナフチレン基、ビナフチレン基、アントラセニレン基、フェナントリレン基、ピレニレン基、フェロセニレン基、フラニレン基、チオフェニレン基、ピリジニレン基、キノリニレン基またはイソキノニレン基である。
【０１２７】
ナフチレン基は、
【０１２８】
【化１９】

【０１２９】
特に
【０１３０】
【化２０】

【０１３１】
である。スチルベニレン基は、
【０１３２】
【化２１】

【０１３３】
である。ビフェニレン基は、
【０１３４】
【化２２】

【０１３５】
である。ｏ−、ｍ−またはｐ−ターフェニレン基は、
【０１３６】
【化２３】

【０１３７】
である。トリフェニルフェニレン基は、
【０１３８】
【化２４】

【０１３９】
である。ビナフチレン基は、
【０１４０】
【化２５】

【０１４１】
特に、
【０１４２】
【化２６】

【０１４３】
である。アントラセニレン基は、
【０１４４】
【化２７】

【０１４５】
である。フェナントリレン基は、
【０１４６】
【化２８】

【０１４７】
である。ピレニレン基は、
【０１４８】
【化２９】

【０１４９】
である。フラニレン基は、
【０１５０】
【化３０】

【０１５１】
である。チオフェニレン基は、
【０１５２】
【化３１】

【０１５３】
である。ピリジニレン基は、
【０１５４】
【化３２】

【０１５５】
である。キノリニレン基は、
【０１５６】
【化３３】

【０１５７】
である。イソキノニレン基は、
【０１５８】
【化３４】

【０１５９】
である。１，４−ドゥリル基は、
【０１６０】
【化３５】

【０１６１】
である。
置換されたフェニレン基、スチルベニレン基、ビフェニレン基、ｏ−、ｍ−またはｐ−ターフェニレン基、トリフェニルフェニレン基、ナフチレン基、ビナフチレン基、アントラセニレン基、フェナントリレン基、ピレニレン基、フェロセニレン基、フラニレン基、チオフェニレン基、ピリジニレン基、キノリニレン基またはイソキノニレン基は、１ないし４回、例えば１、２または３回、特に１または２回置換されている。１，４−フェニレン環上の置換基はフェニル環上の２、３、５または６位、特に２または３位にある。１，３−フェニレン環上の置換基はフェニル環上の２、４、５または６位、特に４または５位にある。
【０１６２】
特に、本発明に於いては、アリール基に導入される置換基は、以下の何れかの態様であることが好ましい。これらは各々別々の技術として効果があるが、組み合わせて用いることは、より好ましい態様である。
【０１６３】
１）ホウ素と結合するアリール基のオルト位に少なくとも置換基を有することが好ましい。
【０１６４】
２）アリール基に電子吸引性基を導入することが好ましい。
本発明で言う、電子吸引性基とはハメット則によるパラ位の置換基効果で得られるσ値が正であるものを言う。具体的には、ニトロ基、ニトロソ基、カルボニル基、カルボキシル基、シアノ基、フルオロアルキル基、フェニル基、アルキルスルホニル基、ハロゲン等を挙げることができる。本発明の特に好ましい電子吸引性置換基はフェニル基、アルキル基、ハロゲン類である。
【０１６５】
本発明の好ましい態様は、アリール基のオルト位に少なくとも置換基を有することであるが、オルト位に加え更に他の置換基を有することも、好ましい態様である。また、オルト位以外の位置に置換基を有することも本発明の態様である。
【０１６６】
又、ホウ素塩のカウンターカチオンを米国特許３，２５９，０６０号のようにリン化合物とすることも好ましい態様である。
【０１６７】
本発明で特に好ましく用いられるホウ素塩化合物は、酸化電位が０〜１．０Ｖであることが好ましく、より好ましくは、０．３〜０．７Ｖ、特に好ましくは０．４〜０．６５Ｖであることが好ましい。ホウ素塩の酸化電位が高いと感度が低く、逆に酸化電位が低いと保存性が劣化するという従来の技術と異なり、本発明においては上記の好ましい電子吸引性基の種類と付加数を調整し、上記範囲に酸化電位を保ち、且つ同時にオルト位に置換基を導入することにより、従来に比べより感度が高く、同時に保存性も良好な傾向となることを見出した。またこの様な改良に伴い、新たな課題として平版印刷版用のアルカリ現像液に対する溶解性が劣化し、現像カスによる汚れ、現像液寿命の短命化という課題が出てきたが、後述の現像液を用いることにより、良好な現像性が得られることを見出し、全ての観点で良好な結果を得るに至った。
【０１６８】
尚、酸化還元電位の測定方法は以下の通りである。
本発明では、ＢＡＳ社製ＢＡＳ１００Ｂエレクトロケミカルアナライザーを用い、作用電極：白金、比較電極：Ａｇ／ＡｇＣｌ、カウンター電極：白金ワイヤーを用いた。支持電解質は、過塩素酸テトラブチルアンモニウムを用い、測定溶剤はアセトニトリル中に、測定物質を溶解し求めた。尚、昇電条件酸化還元電位のピークが得られる条件を探しながら、個々の試料別に設定するため、条件の記載は割愛する。
【０１６９】
（カチオン性色素）
本発明に於いては、特にインドール型シアニン色素、特定構造のローダミン色素、特定構造のサフラニン色素が好ましい。特定構造とは、酸基いわゆるカルボン酸基、スルフオン酸基、燐酸基等の構造を有さないものが好ましい。
【０１７０】
補助開始剤として添加され得る電子受容体として適当な染料の例は米国特許第５，１５１，５２０号に記載されている。例えば、トリアリールメタン、例としてマラカイトグリーン、インドリン、チアジン、例としてメチレンブルー、キサントン、チオキサントン、オキサジン、アクリジンまたはフェナジン、例としてサフラニンである。補助開始剤として、上記遷移貴金属錯体化合物またはオニウムイオン化合物を使用することも可能である。カチオン、中性またはアニオン染料は新規化合物の補助開始剤として使用され得る。特に適当なカチオン染料はマラカイトグリーン、メチレンブルー、サフラニンＯ、一般式（４）で表される化合物、
【０１７１】
【化３６】

【０１７２】
（式中、Ｒ_２およびＲ′はアルキル基またはアリール基を表し、例としてローダミンＢ、ローダミン６ＧまたはバイオラミンＲ等）のローダミン、そしてスルホローダミンＢまたはスルホローダミンＧである。
【０１７３】
その他の適当な染料は、例えばＮｅｃｋｅｒｓ等によりＪ．Ｐｏｌｙｍ．Ｓｃｉ．，Ｐａｒｔ　Ａ，Ｐｏｌｙ．Ｃｈｅｍ．，１９９５，３３，１６９１〜１７０３に記載されているようなフルオロンである。
【０１７４】
【化３７】

【０１７５】
が特に有利である。
その他の適当な染料の例は、一般式（５）で表される化合物、
【０１７６】
【化３８】

【０１７７】
（式中、Ｒ＝アルキル基；ｎ＝０、１、２、３または４、そしてＹ_１＝ＣＨ＝ＣＨ、Ｎ−ＣＨ_３、Ｃ（ＣＨ_３）２、Ｏ、ＳまたはＳｅ）のシアニンである。好ましいシアニンは上記式中Ｙ_１がＣ（ＣＨ_３）_２またはＳのものである。
【０１７８】
以下の染料化合物も補助開始剤として適している。
【０１７９】
【化３９】

【０１８０】
（式中、ＺはＰ、ＳまたはＮを表し、そしてＲ_３はアルキル基またはアリール基を表す）上記式の中の好ましい化合物は、式中Ｚ^＋Ｒ_３がＮ（ＣＨ_３）_３、Ｎ（Ｃ_２Ｈ_５）_３またはＰ（Ｃ_６Ｈ_５）_３であるものである。
【０１８１】
例えばＹａｇｃｉ等によりＪ．Ｐｏｌｙｍ．Ｓｃｉ．Ｐａｒｔ　Ａ：Ｐｏｌｙｍｅｒ　Ｃｈｅｍ．１９９２，３０，１９８７およびＰｏｌｙｍｅｒ　１９９３，３４（６），１１３０に記載されるような、
【０１８２】
【化４０】

【０１８３】
または特開平７−７０２２１号に記載される、
【０１８４】
【化４１】

【０１８５】
（式中、Ｒ′は非置換または置換されたベンジル基またはフェンアシル基を表す）の化合物もまた適当である。上記ピリジニウム化合物は芳香族ピリジニウム環において置換されていてもよい。
【０１８６】
その他の適当な染料は例えば米国特許第４，９０２，６０４号明細書中に見出される。これらはアズレン染料である。新規化合物のための補助開始剤として特に適しているのは上記特許明細書の第１０および１１欄に挙げられた化合物１−１８である。その他の適当な染料の例は米国特許第４，９５０，５８１号明細書の第６欄第２０行〜第９欄第５７行に記載されている。新規化合物および組成物のための補助開始剤として、クマリン化合物を使用することも可能である。これらの例は米国特許第４，９５０，５８１号明細書の第１１欄第２０行〜第１２欄第４２行に記載されている。その他の適当な補助開始剤は例えば米国特許第４，９５０，５８１号明細書の第１２欄第４４行〜第１３欄第１５行に記載されているキサントンまたはチオキサントンである。アニオン染料化合物も、例えば補助開始剤として使用され得る。例えば、ローズベンガル、エオシンまたはフルオレセインも適している。例えばトリアリールメタン類またはアゾ類からのその他の適当な染料は例えば米国特許第５，１４３，８１８号に記載されている。
【０１８７】
（光重合開始剤）
光重合開始剤として、上述した本発明に係る前記一般式（１）で表される化合物の他に、公知の光重合開始剤を併用することができる。
【０１８８】
例えば、Ｊ．コーサー（Ｊ．Ｋｏｓａｒ）著「ライト・センシティブ・システムズ」第５章に記載されるようなカルボニル化合物、有機硫黄化合物、過硫化物、レドックス系化合物、アゾ並びにジアゾ化合物、ハロゲン化合物、光還元性色素などが挙げられる。更に、具体的な化合物は、英国特許１，４５９，５６３号に開示されている。
【０１８９】
即ち、光重合開始剤としては、ベンゾインメチルエーテル、ベンゾイン−ｉ−プロピルエーテル、α，α−ジメトキシ−α−フェニルアセトフェノン等のベンゾイン誘導体；ベンゾフェノン、２，４−ジクロロベンゾフェノン、ｏ−ベンゾイル安息香酸メチル、４，４′−ビス（ジメチルアミノ）ベンゾフェノン等のベンゾフェノン誘導体；２−クロロチオキサントン、２−ｉ−プロピルチオキサントン等のチオキサントン誘導体；２−クロロアントラキノン、２−メチルアントラキノン等のアントラキノン誘導体；Ｎ−メチルアクリドン、Ｎ−ブチルアクリドン等のアクリドン誘導体；α，α−ジエトキシアセトフェノン、ベンジル、フルオレノン、キサントン、ウラニル化合物の他、特公昭５９−１２８１号、同６１−９６２１号並びに特開昭６０−６０１０４号記載のトリアジン誘導体；特開昭５９−１５０４号、同６１−２４３８０７号記載の有機過酸化物；特公昭４３−２３６８４号、同４４−６４１３号、同４４−６４１３号、同４７−１６０４号並びに米国特許３，５６７，４５３号記載のジアゾニウム化合物；米国特許２，８４８，３２８号、同２，８５２，３７９号並びに同２，９４０，８５３号記載の有機アジド化合物；特公昭３６−２２０６２号、同３７−１３１０９号、同３８−１８０１５号並びに同４５−９６１０号記載のｏ−キノンジアジド類；特公昭５５−３９１６２号、特開昭５９−１４０２３号並びに「マクロモレキュルス（Ｍａｃｒｏｍｏｌｅｃｕｌｅｓ）」１０巻，１３０７頁（１９７７年）記載の各種オニウム化合物；特開昭５９−１４２２０５号記載のアゾ化合物；特開平１−５４４４０号、ヨーロッパ特許１０９，８５１号、同１２６，７１２号並びに「ジャーナル・オブ・イメージング・サイエンス（Ｊ．Ｉｍａｇ．Ｓｃｉ．）」３０巻，１７４頁（１９８６年）記載の金属アレン錯体；特開平５−２１３８６１号及び同５−２５５３４７号記載の（オキソ）スルホニウム有機硼素錯体；「コーディネーション・ケミストリー・レビュー（Ｃｏｏｒｄｉｎａｔｉｏｎ　Ｃｈｅｍｉｓｔｒｙ　Ｒｅｖｉｅｗ）」８４巻，８５〜２７７頁（１９８８年）並びに特開平２−１８２７０１号記載のルテニウム等の遷移金属を含有する遷移金属錯体；特開平３−２０９４７７号記載の２，４，５−トリアリールイミダゾール二量体；四臭化炭素、特開昭５９−１０７３４４号記載の有機ハロゲン化合物等を挙げることができる。
【０１９０】
（その他添加剤）
光重合開始剤に加えて、本発明の感光性組成物は、種々の添加剤を含んでもよい。
【０１９１】
増感剤としては、特開昭６４−１３１４０号に記載のトリアジン系化合物、特開昭６４−１３１４１号に記載の芳香族オニウム塩、芳香族ハロニウム塩、特開昭６４−１３１４３号に記載の有機過酸化物、特公昭４５−３７３７７号や米国特許３，６５２，２７５号に記載のビスイミダゾール化合物、チオール類等が挙げられる。増感剤の添加量は、光重合性親油性熱可塑性モノマー／プレポリマーの合計量１００質量部に対して１０質量部以下、好ましくは０．０１〜５質量部程度が添加される。
【０１９２】
早期重合の防止を意図する熱抑制剤（ｔｈｅｒｍａｌ　ｉｎｈｉｂｉｔｏｒ）は、例えばヒドロキノン、ヒドロキノン誘導体、ｐ−メトキシフェノール、β−ナフトールまたは立体障害性フェノール、例えば２，６−ジ−第三ブチル−ｐ−クレゾールである。暗所での貯蔵の安定性を増加させるため、例えば、銅化合物例えば、銅ナフテネート、ステアレートもしくはオクトエート、リン化合物例えば、トリフェニルホスフィン、トリブチルホスフィン、トリエチルホスフィット、トリフェニルホスフィットまたはトリベンジルホスフィット、第四アンモニウム化合物、例えば、塩化テトラメチルアンモニウムもしくは塩化トリメチルベンジルアンモニウム、またはヒドロキシルアミン誘導体、例えば、Ｎ−ジエチルヒドロキルアミンである。重合中に大気酸素を除くためにポリマー中で充分に溶解せず、重合の開始において表面に移動し、空気の進入を防ぐ透明な表層を形成するパラフィン、または同等のワックス様物質を加えることもできる。少量で添加できる光安定剤は紫外線吸収剤、例えば、ヒドロキシフェニルベンゾトリアゾール、ヒドロキシフェニルベンゾフェノン、オキサルアミドまたはヒドロキシフェニル−ｓ−トリアジンタイプのものである。これらの化合物は個別にまたは立体障害性アミン（ＨＡＬＳ）を含むまたは含まない混合物で使用できる。
【０１９３】
上記紫外線吸収剤の例は以下の通りである。
１．２−（２′−ヒドロキシフェニル）ベンゾトリアゾールの例：２−（２′−ヒドロキシ−５′−メチルフェニル）ベンゾトリアゾール、２−（３′，５′−ジ−第三ブチル−２′−ヒドロキシフェニル）ベンゾトリアゾール、２−（５′−第三ブチル−２′−ヒドロキシフェニル）ベンゾトリアゾール、２−（２′−ヒドロキシ−５′−（１，１，３，３−テトラメチルブチル）フェニル）ベンゾトリアゾール、２−（３′，５′−ジ−第三ブチル−２′−ヒドロキシフェニル）−５−クロロベンゾトリアゾール、２−（３′−第三ブチル−２′−ヒドロキシ−５′−メチルフェニル）−５−クロロベンゾトリアゾール、２−（３′−第二ブチル−５′−第三ブチル−２′−ヒドロキシフェニル）ベンゾトリアゾール、２−（２′−ヒドロキシ−４′−オクチルオキシフェニル）ベンゾトリアゾール、２−（３′，５′−ジ−第三アミル−２′−ヒドロキシフェニル）ベンゾトリアゾール、２−（３′，５′−ビス（α，α−ジメチルベンジル）−２′−ヒドロキシフェニル）ベンゾトリアゾール、２−（３′−第三ブチル−２′−ヒドロキシ−５′−（２−オクチルオキシカルボニルエチル）フェニル）−５−クロロベンゾトリアゾール、２−（３′−第三ブチル−５′−〔２−（２−エチルヘキシルオキシ）カルボニルエチル〕−２′−ヒドロキシフェニル）−５−クロロベンゾトリアゾール、２−（３′−第三ブチル−２′−ヒドロキシ−５′−（２−メトキシカルボニルエチル）フェニル）−５−クロロベンゾトリアゾール、２−（３′−第三ブチル−２′−ヒドロキシ−５′−（２−メトキシカルボニルエチル）フェニル）ベンゾトリアゾール、２−（３′−第三ブチル−２′−ヒドロキシ−５′−（２−オクチルオキシカルボニルエチル）フェニル）ベンゾトリアゾール、２−（３′−第三ブチル−５′−〔２−（２−エチルヘキシルオキシ）カルボニルエチル〕−２′−ヒドロキシフェニル）ベンゾトリアゾール、２−（３′−ドデシル−２′−ヒドロキシ−５′−メチルフェニル）ベンゾトリアゾールおよび２−（３′−第三ブチル−２′−ヒドロキシ−５′−（２−イソオクチルオキシカルボニルエチル））フェニルベンゾトリアゾールの混合物、２，２′−メチレンビス〔４−（１，１，３，３−テトラメチルブチル）−６−ベンゾトリアゾール−２−イルフェノール〕；２−〔３′−第三ブチル−５′−（２−メトキシカルボニルエチル）−２′−ヒドロキシフェニル〕−２Ｈ−ベンゾトリアゾールとポリエチレングリコール３００とのエステル交換体；次式：〔Ｒ−ＣＨ_２ＣＨ_２−ＣＯＯ（ＣＨ_２）_３−〕_２−（式中、Ｒは３′−第三ブチル−４′−ヒドロキシ−５′−２Ｈ−ベンゾトリアゾール−２−イルフェニル基を表す）で表される化合物。
【０１９４】
２．２−ヒドロキシ−ベンゾフェノンの例：４−ヒドロキシ−、４−メトキシ−、４−オクチルオキシ−、４−デシルオキシ−、４−ドデシルオキシ−、４−ベンジルオキシ−、４，２′，４′−トリヒドロキシ−および２′−ヒドロキシ−４，４′−ジメトキシ誘導体。
【０１９５】
３．置換されたおよび非置換安息香酸のエステルの例：４−第三ブチルフェニルサリチレート、フェニルサリチレート、オクチルフェニルサリチレート、ジベンゾイルレゾルシノール、ビス（４−第三ブチルベンゾイル）レゾルシノール、ベンゾイルレゾルシノール、２，４−ジ−第三ブチルフェニル３，５−ジ−第三ブチル−４−ヒドロキシベンゾエート、ヘキサデシル３，５−ジ−第三ブチル−４−ヒドロキシベンゾエート、オクタデシル３，５−ジ−第三ブチル−４−ヒドロキシベンゾエート、２−メチル−４，６−ジ−第三ブチルフェニル３，５−ジ−第三ブチル−４−ヒドロキシベンゾエート。
【０１９６】
４．アクリレートの例：エチルα−シアノ−β，β−ジフェニルアクリレート、イソオクチルα−シアノ−β，β−ジフェニル−アクリレート、メチルα−カルボメトキシシンナメート、メチルα−シアノ−β−メチル−ｐ−メトキシシンナメート、ブチルα−シアノ−β−メチル−ｐ−メトキシシンナメート、メチルα−カルボメトキシ−ｐ−メトキシシンナメートおよびＮ−（β−カルボメトキシ−β−シアノビニル）−２−メチルインドリン。
【０１９７】
５．立体障害性アミンの例：ビス（２，２，６，６−テトラメチルピペリジル）セバケート、ビス（２，２，６，６−テトラメチル−４−ピペリジル）スクシネート、ビス（１，２，２，６，６−ペンタメチル−４−ピペリジル）セバケート、ビス（１−オクチルオキシ−２，２，６，６−テトラメチル−４−ピペリジル）セバケート、ビス（１，２，２，６，６−ペンタメチル−４−ピペリジル）ｎ−ブチル−３，５−ジ−第三ブチル−４−ヒドロキシベンジルマロネート、１−（ヒドロキシエチル）−２，２，６，６−テトラメチル−４−ヒドロキシピペリジンとコハク酸との縮合生成物、Ｎ，Ｎ′−ビス（２，２，６，６−テトラメチル−４−ピペリジル）ヘキサメチレンジアミンと４−第三オクチルアミノ−２，６−ジクロロ−１，３，５−トリアジンとの縮合生成物、トリス（２，２，６，６−テトラメチル−４−ピペリジル）ニトリロトリアセテート、テトラキス（２，２，６，６−テトラメチル−４−ピペリジル）−１，２，３，４−ブタンテトラオエート、１，１′−（１，２−エタンジイル）−ビス（３，３，５，５−テトラメチルピペラジノン）、４−ベンゾイル−２，２，６，６−テトラメチルピペリジン、４−ステアリルオキシ−２，２，６，６−テトラメチルピペリジン、ビス（１，２，２，６，６−ペンタメチルピペリジル）−２−ｎ−ブチル−２−（２−ヒドロキシ−３，５−ジ−第三ブチルベンジル）マロネート、３−ｎ−オクチル−７，７，９，９−テトラメチル−１，３，８−トリアザスピロ〔４．５〕デカン−２，４−ジオン、ビス（１−オクチルオキシ−２，２，６，６−テトラメチルピペリジル）セバケート、ビス（１−オクチルオキシ−２，２，６，６−テトラメチルピペリジル）スクシネート、Ｎ，Ｎ′−ビス（２，２，６，６−テトラメチル−４−ピペリジル−４−ピペリジル）ヘキサメチレンジアミンと４−モルホリノ−２，６−ジクロロ−１，３，５−トリアジンとの縮合生成物、２−クロロ−４，６−ビス（４−ｎ−ブチルアミノ−２，２，６，６−テトラメチルピペリジル）−１，３，５−トリアジンと１，２−ビス（３−アミノプロピルアミノ）エタンとの縮合生成物、２−クロロ−４，６−ジ（４−ｎ−ブチルアミノ−１，２，２，６，６−ペンタメチルピペリジル）−１，３，５−トリアジンと１，２−ビス（３−アミノプロピルアミノ）エタンとの縮合生成物、８−アセチル−３−ドデシル−７，７，９，９−テトラメチル−１，３，８−トリアザスピロ〔４．５〕デカン−２，４−ジオンおよび３−ドデシル−１−（１，２，２，６，６−ペンタメチル−４−ピペリジル）ピロリジン−２，５−ジオン。
【０１９８】
６．オキサミドの例：４，４′−ジオクチルオキシオキサニリド、２，２′−ジエトキシオキサニリド、２，２′−ジオクチルオキシ−５，５′−ジ−第三ブトキサニリド、２，２′−ジドデシルオキシ−５，５′−ジ−第三ブトキサニリド、２−エトキシ−２′−エチルオキサニリド、Ｎ，Ｎ′−ビス（３−ジメチルアミノプロピル）オキサミド、２−エトキシ−５−第三ブチル−２′−エトキサニリドおよび該化合物と２−エトキシ−２′−エチル−５，４′−ジ−第三ブトキサニリドとの混合物、オルト−およびパラ−メトキシ−二置換オキサニリドの混合物およびｏ−およびｐ−エトキシ−二置換オキサニリドの混合物。
【０１９９】
７．２−（２−ヒドロキシフェニル）−１，３，５−トリアジンの例：２，４，６−トリス（２−ヒドロキシ−４−オクチルオキシフェニル）−１，３，５−トリアジン、２−（２−ヒドロキシ−４−オクチルオキシフェニル）−４，６−ビス（２，４−ジメチルフェニル）−１，３，５−トリアジン、２−（２，４−ジヒドロキシフェニル）−４，６−ビス（２，４−ジメチルフェニル）−１，３，５−トリアジン、２，４−ビス（２−ヒドロキシ−４−プロピルオキシフェニル）−６−（２，４−ジメチルフェニル）−１，３，５−トリアジン、２−（２−ヒドロキシ−４−オクチルオキシフェニル）−４，６−ビス（４−メチルフェニル）−１，３，５−トリアジン、２−（２−ヒドロキシ−４−ドデシルオキシフェニル）−４，６−ビス（２，４−ジメチルフェニル）−１，３，５−トリアジン、２−（２−ヒドロキシ−４−ドデシルオキシフェニル）−４，６−ビス（２，４−ジメチルフェニル）−１，３，５−トリアジン、２−〔２−ヒドロキシ−４−（２−ヒドロキシ−３−ブチルオキシプロポキシ）フェニル〕−４，６−ビス（２，４−ジメチルフェニル）−１，３，５−トリアジン、２−〔２−ヒドロキシ−４−（２−ヒドロキシ−３−オクチルオキシプロピルオキシ）フェニル〕−４，６−ビス（２，４−ジメチルフェニル）−１，３，５−トリアジン、２−〔４−（ドデシルオキシ／トリデシルオキシ−２−ヒドロキシプロポキシ）−２−ヒドロキシフェニル〕−４，６−ビス（２，４−ジメチルフェニル）−１，３，５−トリアジン。
【０２００】
８．ホスフィットおよびホスホナイトの例：トリフェニルホスフィット、ジフェニルアルキルホスフィット、フェニルジアルキルホスフィット、トリス（ノニルフェニル）ホスフィット、トリラウリルホスフィット、トリオクタデシルホスフィット、ジステアリルペンタエリトリトールジホスフィット、トリス（２，４−ジ−第三ブチルフェニル）ホスフィット、ジイソデシルペンタエリトリトールジホスフィット、ビス（２，４−ジ−第三ブチルフェニル）ペンタエリトリトールジホスフィット、ビス（２，６−ジ−第三ブチル−４−メチルフェニル）ペンタエリトリトールジホスフィット、ジイソデシルオキシペンタエリトリトールジホスフィット、ビス（２，４−ジ−第三ブチル−６−メチルフェニル）ペンタエリトリトールジホスフィット、ビス（２，４，６−トリス（第三ブチルフェニル））ペンタエリトリトールジホスフィット、トリステアリルソルビトールトリホスフィット、テトラキス（２，４−ジ−第三ブチルフェニル）４，４′−ビフェニレンジホスホナイト、６−イソオクチルオキシ−２，４，８，１０−テトラ第三ブチル−１２Ｈ−ジベンゾ〔ｄ，ｇ〕−１，３，２−ジオキサホスホシン、６−フルオロ−２，４，８，１０−テトラ第三ブチル−１２−メチル−ジベンゾ〔ｄ，ｇ〕−１，３，２−ジオキサホスホシン、ビス（２，４−ジ−第三ブチル−６−メチルフェニル）メチルホスフィットおよびビス（２，４−ジ−第三ブチル−６−メチルフェニル）エチルホスフィット。
【０２０１】
光重合を促進するために、アミン、例えばトリエタノールアミン、Ｎ−メチルジエタノールアミン、ｐ−ジメチルアミノベンゾエートまたはミヒラーケトンを加えることが可能である。アミンの作用はベンゾフェノンタイプの芳香族ケトンの添加により強化できる。酸素掃去剤として使用できるアミンの例はＥＰ−Ａ−３３９８４１号公開公報に記載される置換Ｎ，Ｎ−ジアルキルアニリンである。他の促進剤、補助開始剤および自動酸化剤は、例えば、ＥＰ−Ａ−４３８１２３、ＢＧ−２１８０３５８および特開平６−２６８３０９号に記載されるような、チオール、チオエーテル、ジスルフィド、ホスホニウム塩、ホスフィンオキシドまたはホスフィンである。光重合はまた、スペクトル感受性をシフトまたは拡張する他の増感剤を加えることによっても促進される。それらは特に芳香族カルボニル化合物、例えばベンゾフェノン、チオキサントン、アントラキノンおよび３−アシルクマリン誘導体であり、および、または３−（アロイルメチレン）チアゾリンでもあるが、エオシン、ローダミンおよびエリスロシン染料でもある。
【０２０２】
硬化工程は特に（例えば二酸化チタンにより）着色された組成物により、および、または加熱条件下でフリーラジカルを形成する成分、例えば２，２′−アゾビス（４−メトキシ−２，４−ジメチル）バレロニトリルのようなアゾ化合物、トリアゼン、ジアゾスルフィド、ペンタザジエン、あるいはパーオキシ化合物、例えば、ヒドロパーオキシドまたはパーオキシカーボネート、例えばＥＰ−Ａ−２４５６３９に記載されるような第三ブチルヒドロパーオキシドを加えることにより補助できる。
【０２０３】
他の慣用の添加剤は意図する用途によるが、蛍光増白剤、充填剤、顔料、染料、湿潤剤もしくは均展剤である。厚い塗膜および着色した塗膜の硬化のためには、米国特許第５，０１３，７６８号に記載されているようにガラス微小球又は粉末化したガラス繊維の添加が適当である。
【０２０４】
（保護層：酸素遮断層）
本発明に係る光重合性感光層の上側には、保護層を設けることが好ましい。該保護層（酸素遮断層）は、後述の現像液（一般にはアルカリ水溶液）への溶解性が高いことが好ましく、具体的には、ポリビニルアルコール及びポリビニルピロリドンを挙げることができる。ポリビニルアルコールは酸素の透過を抑制する効果を有し、また、ポリビニルピロリドンは隣接する感光層との接着性を確保する効果を有する。
【０２０５】
上記２種のポリマーの他に、必要に応じ、ポリサッカライド、ポリエチレングリコール、ゼラチン、膠、カゼイン、ヒドロキシエチルセルロース、カルボキシメチルセルロース、メチルセルロース、ヒドロキシエチル澱粉、アラビアゴム、サクローズオクタアセテート、アルギン酸アンモニウム、アルギン酸ナトリウム、ポリビニルアミン、ポリエチレンオキシド、ポリスチレンスルホン酸、ポリアクリル酸、水溶性ポリアミド等の水溶性ポリマーを併用することもできる。
【０２０６】
本発明に係る平版印刷版では、感光層と保護層間の剥離力が３５ｍＮ／ｍｍ以上であることが好ましく、より好ましくは５０ｍＮ／ｍｍ以上、更に好ましくは７５ｍＮ／ｍｍ以上である。好ましい保護層の組成としては特願平８−１６１６４５号に記載されるものが挙げられる。
【０２０７】
本発明における剥離力は、保護層上に十分大きい粘着力を有する所定幅の粘着テープを貼り、それを平版印刷版材料の平面に対して９０度の角度で保護層と共に剥離する時の力を測定することにより求めることができる。
【０２０８】
保護層には、更に必要に応じて界面活性剤、マット剤等を含有することができる。上記保護層組成物を適当な溶剤に溶解し感光層上に塗布・乾燥して保護層を形成する。塗布溶剤の主成分は水、あるいはメタノール、エタノール、ｉ−プロパノール等のアルコール類であることが特に好ましい。
【０２０９】
保護層の厚みは０．１〜５．０μｍが好ましく、特に好ましくは０．５〜３．０μｍである。
【０２１０】
（支持体）
本発明に係る支持体は、親水性表面を有する、例えばアルミニウム、ステンレス、クロム、ニッケル等の金属板、また、ポリエステルフィルム、ポリエチレンフィルム、ポリプロピレンフィルム等のプラスチックフィルムに前述の金属薄膜をラミネートまたは蒸着したもの等が使用でき、また、ポリエステルフィルム、塩化ビニルフィルム、ナイロンフィルム等の表面に親水化処理を施したもの等が使用できるが、アルミニウム支持体が好ましく使用され、この場合、純アルミニウムまたはアルミニウム合金であってもかまわない。
【０２１１】
支持体のアルミニウム合金としては、種々のものが使用でき、例えば、珪素、銅、マンガン、マグネシウム、クロム、亜鉛、鉛、ビスマス、ニッケル、チタン、ナトリウム、鉄等の金属とアルミニウムの合金が用いられる。
【０２１２】
本発明に係る支持体は、粗面化（砂目立て処理）するに先立って表面の圧延油を除去するために脱脂処理を施すことが好ましい。脱脂処理としては、トリクレン、シンナー等の溶剤を用いる脱脂処理、ケシロン、トリエタノール等のエマルジョンを用いたエマルジョン脱脂処理等が用いられる。又、脱脂処理には、苛性ソーダ等のアルカリの水溶液を用いることもできる。脱脂処理に苛性ソーダ等のアルカリ水溶液を用いた場合、上記脱脂処理のみでは除去できない汚れや酸化皮膜も除去することができる。脱脂処理に苛性ソーダ等のアルカリ水溶液を用いた場合、支持体の表面にはスマットが生成するので、この場合には、燐酸、硝酸、硫酸、クロム酸等の酸、或いはそれらの混酸に浸漬しデスマット処理を施すことが好ましい。粗面化の方法としては、例えば、機械的方法、電解によりエッチングする方法が挙げられる。
【０２１３】
用いられる機械的粗面化法は特に限定されるものではないが、ブラシ研磨法、ホーニング研磨法が好ましい。ブラシ研磨法による粗面化は、例えば、直径０．２〜０．８ｍｍのブラシ毛を使用した回転ブラシを回転し、支持体表面に、例えば、粒径１０〜１００μｍの火山灰の粒子を水に均一に分散させたスラリーを供給しながら、ブラシを押し付けて行うことができる。ホーニング研磨による粗面化は、例えば、粒径１０〜１００μｍの火山灰の粒子を水に均一に分散させ、ノズルより圧力をかけ射出し、支持体表面に斜めから衝突させて粗面化を行うことができる。又、例えば、支持体表面に、粒径１０〜１００μｍの研磨剤粒子を、１００〜２００μｍの間隔で、２．５×１０^３〜１０×１０^３個／ｃｍ^２の密度で存在するように塗布したシートを張り合わせ、圧力をかけてシートの粗面パターンを転写することにより粗面化を行うこともできる。
【０２１４】
上記の機械的粗面化法で粗面化した後、支持体の表面に食い込んだ研磨剤、形成されたアルミニウム屑等を取り除くため、酸又はアルカリの水溶液に浸漬することが好ましい。酸としては、例えば、硫酸、過硫酸、弗酸、燐酸、硝酸、塩酸等が用いられ、塩基としては、例えば水酸化ナトリウム、水酸化カリウム等が用いられる。これらの中でも、水酸化ナトリウム等のアルカリ水溶液を用いるのが好ましい。表面のアルミニウムの溶解量としては、０．５〜５ｇ／ｍ^２が好ましい。アルカリ水溶液で浸漬処理を行った後、燐酸、硝酸、硫酸、クロム酸等の酸或いはそれらの混酸に浸漬し中和処理を施すことが好ましい。
【０２１５】
電気化学的粗面化法も特に限定されるものではないが、酸性電解液中で電気化学的に粗面化を行う方法が好ましい。酸性電解液は、電気化学的粗面化法に通常用いられる酸性電解液を使用することができるが、塩酸系または硝酸系電解液を用いるのが好ましい。電気化学的粗面化方法については、例えば、特公昭４８−２８１２３号公報、英国特許第８９６，５６３号公報、特開昭５３−６７５０７号公報に記載されている方法を用いることができる。この粗面化法は、一般には、１〜５０ボルトの範囲の電圧を印加することによって行うことができるが、１０〜３０ボルトの範囲から選ぶのが好ましい。電流密度は、１０〜２００Ａ／ｄｍ^２の範囲を用いることが出来るが、５０〜１５０Ａ／ｄｍ^２の範囲から選ぶのが好ましい。電気量は、１００〜５０００ｃ／ｄｍ^２の範囲を用いることができるが、１００〜２０００ｃ／ｄｍ^２の範囲から選ぶのが好ましい。この粗面化法を行う温度は、１０〜５０℃の範囲を用いることが出来るが、１５〜４５℃の範囲から選ぶのが好ましい。
【０２１６】
電解液として硝酸系電解液を用いて電気化学的粗面化を行う場合、一般には、１〜５０ボルトの範囲の電圧を印加することによって行うことができるが、１０〜３０ボルトの範囲から選ぶのが好ましい。電流密度は、１０〜２００Ａ／ｄｍ^２の範囲を用いることができるが、２０〜１００Ａ／ｄｍ^２の範囲から選ぶのが好ましい。電気量は、１００〜５０００ｃ／ｄｍ^２の範囲を用いることができるが、１００〜２０００ｃ／ｄｍ^２の範囲から選ぶのが好ましい。電気化学的粗面化法を行う温度は、１０〜５０℃の範囲を用いることができるが、１５〜４５℃の範囲から選ぶのが好ましい。電解液における硝酸濃度は０．１〜５質量％が好ましい。電解液には、必要に応じて、硝酸塩、塩化物、アミン類、アルデヒド類、燐酸、クロム酸、ホウ酸、酢酸、しゅう酸等を加えることができる。
【０２１７】
電解液として塩酸系電解液を用いる場合、一般には、１〜５０ボルトの範囲の電圧を印加することによって行うことができるが、２〜３０ボルトの範囲から選ぶのが好ましい。電流密度は、１０〜２００Ａ／ｄｍ^２の範囲を用いることができるが、５０〜１５０Ａ／ｄｍ^２の範囲から選ぶのが好ましい。電気量は、１００〜５０００ｃ／ｄｍ^２の範囲を用いることができるが、１００〜２０００ｃ／ｄｍ^２、更には２００〜１０００ｃ／ｄｍ^２の範囲から選ぶのが好ましい。電気化学的粗面化法を行う温度は、１０〜５０℃の範囲を用いることができるが、１５〜４５℃の範囲から選ぶのが好ましい。電解液における塩酸濃度は０．１〜５質量％が好ましい。
【０２１８】
上記の電気化学的粗面化法で粗面化した後、表面のアルミニウム屑等を取り除くため、酸又はアルカリの水溶液に浸漬することが好ましい。酸としては、例えば、硫酸、過硫酸、弗酸、燐酸、硝酸、塩酸等が用いられ、塩基としては、例えば、水酸化ナトリウム、水酸化カリウム等が用いられる。これらの中でもアルカリの水溶液を用いるのが好ましい。表面のアルミニウムの溶解量としては、０．５〜５ｇ／ｍ^２が好ましい。又、アルカリの水溶液で浸漬処理を行った後、燐酸、硝酸、硫酸、クロム酸等の酸或いはそれらの混酸に浸漬し中和処理を施すことが好ましい。
【０２１９】
機械的粗面化処理法、電気化学的粗面化法はそれぞれ単独で用いて粗面化してもよいし、又、機械的粗面化処理法に次いで電気化学的粗面化法を行って粗面化してもよい。
【０２２０】
粗面化処理の次には、陽極酸化処理を行うことができる。本発明において用いることができる陽極酸化処理の方法には特に制限はなく、公知の方法を用いることができる。陽極酸化処理を行うことにより、支持体上には酸化皮膜が形成される。該陽極酸化処理には、硫酸及び／又は燐酸等を１０〜５０％の濃度で含む水溶液を電解液として、電流密度１〜１０Ａ／ｄｍ^２で電解する方法が好ましく用いられるが、他に、米国特許第１，４１２，７６８号公報に記載されている硫酸中で高電流密度で電解する方法や、同３，５１１，６６１号公報に記載されている燐酸を用いて電解する方法、クロム酸、シュウ酸、マロン酸等を一種又は二種以上含む溶液を用いる方法等が挙げられる。形成された陽極酸化被覆量は、１〜５０ｍｇ／ｄｍ^２が適当であり、好ましくは１０〜４０ｍｇ／ｄｍ^２である。陽極酸化被覆量は、例えばアルミニウム板を燐酸クロム酸溶液（燐酸８５％液：３５ｍｌ、酸化クロム（ＩＶ）：２０ｇを１Ｌの水に溶解して作製）に浸積し、酸化被膜を溶解し、板の被覆溶解前後の質量変化測定等から求められる。
【０２２１】
陽極酸化処理された支持体は、必要に応じ封孔処理を施してもよい。これら封孔処理は、熱水処理、沸騰水処理、水蒸気処理、珪酸ソーダ処理、重クロム酸塩水溶液処理、亜硝酸塩処理、酢酸アンモニウム処理等公知の方法を用いて行うことができる。
【０２２２】
処理後の支持体表面の中心線平均粗さ（Ｒａ）は０．２〜０．７μｍであることが好ましく、更に０．５〜０．７μｍであることが好ましい。
【０２２３】
更に、これらの処理を行った後に、水溶性の樹脂、たとえばポリビニルホスホン酸、スルホン酸基を側鎖に有する重合体および共重合体、ポリアクリル酸、水溶性金属塩（例えばホウ酸亜鉛）もしくは、黄色染料、アミン塩等を下塗りしたものも好適である。更に、特開平５−３０４３５８号公報に開示されているようなラジカルによって付加反応を起し得る官能基を共有結合させたゾル−ゲル処理基板も好適に用いられる。
【０２２４】
（塗布）
調製された感光性組成物（感光層塗布液）は、従来公知の方法で支持体上に塗布し、乾燥し、感光性平版印刷版材料を作製することが出来る。塗布液の塗布方法としては、例えばエアドクタコータ法、ブレードコータ法、ワイヤバー法、ナイフコータ法、ディップコータ法、リバースロールコータ法、グラビヤコータ法、キャストコーティング法、カーテンコータ法及び押し出しコータ法等を挙げることが出来る。
【０２２５】
感光層の乾燥温度は、低いと十分な耐刷性を得ることが出来ず、又高過ぎるとマランゴニーを生じてしまうばかりか、非画線部のカブリを生じてしまう。好ましい乾燥温度範囲としては、６０〜１６０℃の範囲が好ましく、より好ましくは８０〜１４０℃、特に好ましくは、９０〜１２０℃の範囲で乾燥することが好ましい。
【０２２６】
（画像形成方法）
本発明に係る平版印刷版に画像露光する光源としては、例えばレーザー、発光ダイオード、キセノンランプ、キセノンフラッシュランプ、ハロゲンランプ、カーボンアーク燈、メタルハライドランプ、タングステンランプ、高圧水銀ランプ、無電極光源等を挙げることができる。
【０２２７】
一括露光する場合には、光重合性感光層上に、所望の露光画像のネガパターンを遮光性材料で形成したマスク材料を重ね合わせ、露光すればよい。
【０２２８】
発光ダイオードアレイ等のアレイ型光源を使用する場合や、ハロゲンランプ、メタルハライドランプ、タングステンランプ等の光源を、液晶、ＰＬＺＴ等の光学的シャッター材料で露光制御する場合には、画像信号に応じたデジタル露光をすることが可能であり好ましい。この場合は、マスク材料を使用せず、直接書込みを行うことができる。
【０２２９】
レーザー露光の場合には、光をビーム状に絞り画像データに応じた走査露光が可能なので、マスク材料を使用せず、直接書込みを行うのに適している。又、レーザーを光源として用いる場合には、露光面積を微小サイズに絞ることが容易であり、高解像度の画像形成が可能となる。
【０２３０】
レーザー光源としては、アルゴンレーザー、Ｈｅ−Ｎｅガスレーザー、ＹＡＧレーザー、半導体レーザー等を何れも好適に用いることが可能であるが、本発明においては、ＩｎＧａＮ系やＺｎＳｅ系の材料を用い、３８０〜４３０ｎｍ域で連続発振可能な半導体レーザーを用いることが、本発明の効果をいかんなく発揮する上で、特に好ましい。
【０２３１】
レーザーの走査方法としては、円筒外面走査、円筒内面走査、平面走査などがある。円筒外面走査では、記録材料を外面に巻き付けたドラムを回転させながらレーザー露光を行い、ドラムの回転を主走査としレーザー光の移動を副走査とする。円筒内面走査では、ドラムの内面に記録材料を固定し、レーザービームを内側から照射し、光学系の一部又は全部を回転させることにより円周方向に主走査を行い、光学系の一部又は全部をドラムの軸に平行に直線移動させることにより軸方向に副走査を行う。平面走査では、ポリゴンミラーやガルバノミラーとｆθレンズ等を組み合わせてレーザー光の主走査を行い、記録媒体の移動により副走査を行う。円筒外面走査及び円筒内面走査の方が光学系の精度を高め易く、高密度記録には適している。
【０２３２】
ホウ素塩＋カチオン染料開始剤系は、光照射によるラジカル発生により、カチオン染料が分解され、消色していくことが知られている。この反応が光強度により大きく異なり、レーザー光版面強度が１０ｍＷより小さい場合、分解反応の進行が優勢で求めるような耐刷性を得られず、又、レーザー光版面強度が２００ｍＷより大きい場合、消色反応は優先しないが、同一露光量に於ける耐刷性が、何故か向上しないことを見出した。
【０２３３】
またこの現象が、露光波長が短波にシフトすることが顕著に見られることを見出した。
【０２３４】
（現像処理液）
本発明で好ましく用いられる処理液は、ｐＨ１０．０〜１２．５の従来の現像液を、特に制限無く使用できる。本発明で使用される現像液のｐＨは、１０．０〜１２．５であるが、下回ると画像形成ができなくなり、逆に範囲を超えると過現像になったり、露光部の現像でのダメージが強くなるという問題が生じる。尚、好ましいｐＨ範囲は、１０．５〜１２．５であり、特に好ましい範囲は１１．０〜１２．５である。
【０２３５】
また、本発明で使用される現像液の導電率は、３〜３０ｍＳ／ｃｍであることが好ましいが、下回ると、通常、アルミニウム板支持体表面の感光性組成物の溶出が困難となり、印刷で汚れを伴ってしまい、逆に範囲を超えると、塩濃度が高いため、感光層の溶出速度が極端に遅くなり、未露光部に残膜が生じる。導電率の範囲は、更に好ましくは５〜２０ｍＳ／ｃｍの範囲である。
【０２３６】
上述のように本発明の好ましいホウ素塩化合物は、アルカリ水溶液に対する現像性が著しく低下しており、光重合層の非画像部を溶解または膨潤でき、２０℃において水に対する溶解度が１０質量％以下の有機溶剤が好ましく使用できる。
【０２３７】
具体的な有機溶剤としては、例えば、酢酸エチル、酢酸プロピル、酢酸ブチル、酢酸アミル、酢酸ベンジル、エチレングリコールモノブチルアセテート、乳酸ブチル、レプりん酸ブチル等のカルボン酸エステル；エチルブチルケトン、メチルイソブチルケトン、シクロヘキサノン等のケトン類；エチレングリコールモノブチルエーテル、エチレングリコールベンジルエーテル、エチレングリコールモノフェニルエーテル、ベンジルアルコール、メチルフェニルカルビノール、ｎ−アミルアルコール、メチルアミルアルコール等のアルコール類；キシレン等のアルキル置換芳香族炭化水素；メチレンジクロライド、エチレンジクロライド、モノクロロベンゼン等のハロゲン化炭化水素；等が挙げられ、中でもエチレングリコールモノフェニルエーテルとベンジルアルコールが特に好ましい。現像液中の有機溶剤の含有量は、１〜２０質量％程度、好ましくは２〜１０質量％である。
【０２３８】
但し、近年現像液の有機溶剤は環境面から嫌われる傾向が強く、このような有機溶剤を用いない現像処理液が求められている。この様な観点から本発明の好ましい現像処理液は、有機溶剤を用いず、アルカリ剤と界面活性剤とを必須成分として含有するものを挙げることができる。
【０２３９】
現像液中に含有されるアルカリ剤としては、珪酸ナトリウム、珪酸カリウム、水酸化ナトリウム、水酸化カリウム、水酸化リチウム、第２または第３りん酸ナトリウムまたはアンモニウム塩、メタ珪酸ナトリウム、炭酸ナトリウム、炭酸水素ナトリウム、炭酸カリウム、アンモニア、モノメチルアミン、ジメチルアミン、トリメチルアミン、モノエチルアミン、ジエチルアミン、トリエチルアミン、モノイソプロピルアミン、ジイソプロピルアミン、ｎ−ブチルアミン、モノエタノールアミン、ジエタノールアミン、トリエタノールアミン、モノイソプロパノールアミン、ジイソプロパノールアミン、トリイソプロパノールアミン、エチレンイミン、エチレンジアミン等が挙げられ、好ましくは珪酸カリウム、珪酸ナトリウム、第２りん酸ナトリウム、炭酸ナトリウム、炭酸水素ナトリウム、炭酸カリウム、モノエタノールアミン、ジエタノールアミン、トリエタノールアミンである。現像液中のアルカリ剤の含有量は通常０．０５〜８質量％程度、好ましくは０．５〜６質量％である。
【０２４０】
界面活性剤としては、ノニオン系、アニオン系、カチオン系、両性など従来公知の化合物を特に制限なく使用可能であるが、本発明において特に好ましくは、ノニオン及びアニオン性界面活性剤である。
【０２４１】
本発明における特に好ましい活性剤は、下記一般式（６）により表される、ポリオキシアルキレンエーテル基を有するノニオン界面活性剤及びその末端ＯＨをアニオン塩に置換した化合物である。これらの界面活性剤を用いることで、良好な現像性と現像カスによる汚れ、現像液寿命を延ばすことが可能となることを見出した。
【０２４２】
【化４２】

【０２４３】
（式中、Ｒ_１は置換基を有しても良い炭素数３〜１５のアルキル基、置換基を有しても良い炭素数６〜１５の芳香族炭化水素基、又は置換基を有しても良い炭素数４〜１５の複素芳香族環基（尚、置換基としては炭素数１〜２０のアルキル基、Ｂｒ、Ｃｌ、Ｉ等のハロゲン原子、炭素数６〜１５の芳香族炭化水素基、炭素数７〜１７のアラルキル基、炭素数１〜２０のアルコキシ基、炭素数２〜２０のアルコキシ−カルボニル基、炭素数２〜１５のアシル基が挙げられる。）を示し、Ｒ_２は、置換基を有しても良い炭素数１〜１００のアルキレン基（尚、置換基としては、炭素数１〜２０のアルキル基、炭素数６〜１５の芳香族炭化水素基が挙げられる。）を示し、ｎは１〜１００の整数を表す。）
また上記一般式の（Ｒ_２−Ｏ）_ｎの部分は、上記範囲であれば、２種、又は３種の基であっても良い。具体的にはエチレンオキシ基とプロピレンオキシ基、エチレンオキシ基とイソプロピルオキシ基、エチレンオキシ基とブチレンオキシ基、エチレンオキシ基とイソブチレン基等の組み合わせでランダム又はブロック状に連なったもの等が挙げられる。本発明において、ポリオキシアルキレンエーテル基を有する界面活性剤は、単独又は複合系で使用され、現像液中、１〜３０質量％、好ましくは２〜２０質量％添加することが効果的である。添加量が少ないと現像性の低下が、逆に多すぎると現像のダメージが強くなり、印刷版の耐刷性を低下させてしまう。
【０２４４】
またさらに以下に記す、その他の界面活性剤を加えてもよい。その他の界面活性剤としては、例えば、ポリオキシエチレンラウリルエーテル、ポリオキシエチレンセチルエーテル、ポリオキシエチレンステアリルエーテル等のポリオキシエチレンアルキルエーテル類、ポリオキシエチレンオクチルフェニルエーテル、ポリオキシエチレンノニルフェニルエーテル等のポリオキシエチレンアルキルアリルエーテル類、ポリオキシエチレンステアレート等のポリオキシエチレンアルキルエステル類、ソルビタンモノラウレート、ソルビタンモノステアレート、ソルビタンジステアレート、ソルビタンモノオレエート、ソルビタンセスキオレエート、ソルビタントリオレエート等のソルビタンアルキルエステル類、グリセロールモノステアレート、グリセロールモノオレート等のモノグリセリドアルキルエステル類等のノニオン界面活性剤；ドデシルベンゼンスルホン酸ナトリウム等のアルキルベンゼンスルホン酸塩類、ブチルナフタレンスルホン酸ナトリウム、ペンチルナフタレンスルホン酸ナトリウム、ヘキシルナフタレンスルホン酸ナトリウム、オクチルナフタレンスルホン酸ナトリウム等のアルキルナフタレンスルホン酸塩類、ラウリル硫酸ナトリウム等のアルキル硫酸塩類、ドデシルスルホン酸ソーダ等のアルキルスルホン酸塩類、ジラウリルスルホコハク酸ナトリウム等のスルホコハク酸エステル塩類等のアニオン界面活性剤；ラウリルベタイン、ステアリルベタイン等のアルキルベタイン類、アミノ酸類等の両性界面活性剤等が使用可能であるが、特に好ましいのはアルキルナフタレンスルホン酸塩類等のアニオン界面活性剤である。これら界面活性剤は単独、もしくは組み合わせて使用することができる。また、これら界面活性剤の現像液中における含有量は有効成分換算で０．１〜２０質量％が好ましい。
【０２４５】
また、保存安定性、耐刷性等をより高めるために、亜硫酸ナトリウム、亜硫酸カリウム、亜硫酸リチウム、亜硫酸マグネシウム等の水溶性亜硫酸塩を現像液組成の０．０５〜４質量％程度、好ましくは０．１〜１質量％現像液中に含有せしめるのが好ましい。更に、有機溶剤の水への溶解を助けるために、可溶化剤を含有させてもよい。
【０２４６】
【実施例】
以下、実施例により本発明をさらに具体的に説明するが、本発明はこれに限定されるものではない。尚、実施例における「部」は、特に断りない限り「質量部」を表す。
【０２４７】
〔実施例１〕
（本発明１〜４、比較例１〜５）
（バインダーの合成）
窒素気流下の三ツ口フラスコに、メタクリル酸メチル（下記化合物１）４６．０部（０．４６モル）、メタクリル酸（下記化合物２）４１．４部（０．４８モル）、メタクリル酸エチル（下記化合物３）６．７部（０．０６モル）、エタノール１００部及びα，α′−アゾビスイソブチロニトリル１．２３部を入れ、窒素気流中８０℃のオイルバスで６時間反応させて高分子重合体を得た。その後、該重合体に、トリエチルベンジルアンモニウムクロライド１部及びグリシジルメタクリレート（エポキシ基含有不飽和化合物：下記化合物４）４２．５部（０．３モル）を加えて、温度２５℃で３時間反応させて合成バインダーＡ（下記化合物５）を得た。ＧＰＣを用いて測定した重量平均分子量は約７０，０００であった。
【０２４８】
以下、表１に示すモノマー単位比率およびカルボキシル基に反応させるエポキシ基含有不飽和化合物の比率を、仕込量を変えることで変更し、また、重合体の反応時間を調整することで重量平均分子量を変更し、同様の操作を行って、合成バインダーＡ〜Ｇを得た。
【０２４９】
【表１】

【０２５０】
【化４３】

【０２５１】
【化４４】

【０２５２】
【化４５】

【０２５３】
【化４６】

【０２５４】
【化４７】

【０２５５】
（支持体の作製）
厚さ０．２４ｍｍのアルミニウム板（材質１０５０，調質Ｈ１６）を６５℃に保たれた５％水酸化ナトリウム水溶液に浸漬し、１分間の脱脂処理を行った後、水洗した。この脱脂アルミニウム板を、２５℃に保たれた１０％塩酸水溶液中に１分間浸漬して中和した後、水洗した。次いで、このアルミニウム板を、０．３質量％の塩酸水溶液中で、２５℃、電流密度１００Ａ／ｄｍ^２の条件下に交流電流により６０秒間、電解粗面化を行った後、６０℃に保たれた５％水酸化ナトリウム水溶液中で１０秒間のデスマット処理を行った。デスマット処理を行った粗面化アルミニウム板を、１５％硫酸溶液中で、２５℃、電流密度１０Ａ／ｄｍ^２、電圧１５Ｖの条件下に１分間陽極酸化処理を行い、更に３％硅酸ナトリウムで９０℃の封孔処理を行って支持体を作製した。この時、表面の中心線平均粗さ（Ｒａ）は０．６５μｍであった。
【０２５６】
（支持体の表面処理）
上記作製した支持体を、続けて下記溶液中で浸漬し処理を行った。
【０２５７】
溶液温度　　　　　　　　　　　　　　　　　　　　　　　　　　　８０℃
ビニルホスホン酸　　　　　　　　　　　　　　　　　　　　０．２質量％
ポリビニルホスホン酸　　　　　　　　　　　　　　　　　　１．５質量％
上記溶液中にアルミニウム板を３０秒間通し、乾燥した。
【０２５８】
（平版印刷版材料の作製）
上記表面処理済み支持体上に、下記組成の光重合性感光層塗工液を乾燥時２．０ｇ／ｍ^２になるようワイヤーバーで塗布し、９５℃で１．５分間乾燥した。その後、更に該感光層上に、下記組成のオーバーコート層塗工液を乾燥時２．０ｇ／ｍ^２になるようにアプリケーターで塗布し、７５℃で１．５分間乾燥して、感光層上にオーバーコート層を有する平版印刷版材料を作製した。
【０２５９】
感光層塗工面を金属ローラー（ＳＵＳ）にて線圧２９．４Ｎで接触させ、ＳＵＳに感光層が移行するか確認し、タック試験とした。
【０２６０】

【０２６１】
（画像形成）
このようにして作製した光重合型平版印刷版材料について、ＦＤ−ＹＡＧレーザー光源を搭載したＣＴＰ露光装置（Ｔｉｇｅｒｃａｔ：ＥＣＲＭ社製）を用いて２５４０ｄｐｉ（ｄｐｉとは１インチ即ち２．５４ｃｍ当たりのドット数を表す）の解像度で画像露光を行った。次いで、現像前に加熱装置部、オーバーコート層を除去する前水洗部、下記現像液組成を充填した現像部、版面に付着した現像液を取り除く水洗部、画線部保護のためのガム液（ＧＷ−３：三菱化学社製を２倍希釈したもの）を備えたＣＴＰ自動現像機（ＰＨＷ２３−Ｖ：Ｔｅｃｈｎｉｇｒａｐｈ社製）で現像処理を行い、本発明１〜４及び比較例１〜５の平版印刷版を得た。このとき加熱装置部は、版面温度１１５℃、版滞在時間１５秒となるように設定した。また露光終了から自現機の加熱装置部への版挿入は６０秒以内に行った。
【０２６２】
（現像液組成）
Ａケイ酸カリ（珪酸カリウム）　　　　　　　　　　　　　　８．０質量％
ペレックスＮＢＬ：花王（株）製　　　　　　　　　　　　　３．０質量％
苛性カリ　　　　　　　　　　　　　　　　　ｐＨ＝１２．３なるよう調整
（平版印刷版の評価）
上記のようにして得られた平版印刷版について、以下の評価をした。
【０２６３】
《感度》
レーザーの露光エネルギーを変化させ、１００％ベタ画像濃度を露光エネルギー毎に測定し、最高ベタ濃度から−１０％の反射濃度の点を最低画像形成エネルギー＝感度とした。
【０２６４】
《汚れ》
１０００枚連続印刷後印刷版をクリーナーでふき、１５分後に印刷を再開し、５０枚以内で汚れがなくなるかどうかを目視で判定した。
【０２６５】
《保存安定性》
光重合型平版印刷版材料を強制劣化させるため、５５℃、２０％の環境下の恒温槽に３日間保存し、保存する以前のサンプルと比較し、上記の感度評価を行い保存の影響を比較評価した。
【０２６６】
結果は、全て表２に示した。
【０２６７】
【表２】

【０２６８】
【化４８】

【０２６９】
表２の結果より、画像形成した感光性平版印刷版材料の内、本発明１〜４は、タック、感度、汚れ、並びに保存安定性が比較例に対し優れていることが分かった。
【０２７０】
〔実施例２〕
（本発明５〜１２、比較例６〜８）
支持体の作製および表面処理は、実施例１同様に作製した。バインダーは上記で作製した物から選択して使用した。
【０２７１】
（支持体への下引き層）
上記支持体上に、下記組成の下引き層塗工液を乾燥時０．２ｇ／ｍ^２になるようワイヤーバーで塗布し、１００℃で３分間の加熱処理を行って、下引き済み支持体を作製した。
【０２７２】
（下引き層塗工液）
γ−メタクリロキシプロピルトリメトキシシラン　　　　　　　　　　１部
メチルエチルケトン　　　　　　　　　　　　　　　　　　　　　　８０部
シクロヘキサノン　　　　　　　　　　　　　　　　　　　　　　　１９部
（平版印刷版材料の作製）
上記下引き済み支持体上に、下記組成の光重合性感光層塗工液に変更した以外は実施例１と同様の操作を行い、感光層上にオーバーコート層を有する平版印刷版材料を作製した。
【０２７３】

【０２７４】
実施例１と同様の操作を行い、画像形成し、平版印刷版の評価を行った。評価結果を表３に示す。表３では、以下の耐刷評価も加えて評価した。
【０２７５】
《耐刷性》
１７５線の画像を適性露光量で露光、現像して作製した平版印刷版を、印刷機（三菱重工業（株）製ＤＡＩＹＡ１Ｆ−１）で、コート紙、印刷インキ（東洋インク（株）製トーヨーキングハイエコーＭ紅）及び湿し水（東京インク（株）製Ｈ液ＳＧ−５１濃度１．５％）を用いて印刷を行い、ハイライト部の点が３％細る又は、シャドウ部の絡みが発生する印刷枚数を耐刷性の指標とした。
【０２７６】
【表３】

【０２７７】
表３の結果より、本発明例５〜１２は、タック、感度、汚れ、保存安定性並びに耐刷性が良好であり、特に３級アミンモノマーとして化合物Ａを用いた本発明９〜１２は、感度、保存安定性並びに耐刷性が著しく良好になることが分かった。
【０２７８】
〔実施例３〕
（本発明１３〜２２）
本発明５の分光増感色素１及びトリアリールモノアルキルホウ素塩（昭和電工社製：Ｎ３Ｂ）を添加するかわりに、表４の化合物（下記化合物）を表４の添加量で添加し、オーバーコートは本発明５と同様にして本発明１３〜２２を作製した。
【０２７９】
《保存安定性》
光重合型平版印刷版材料を強制劣化させるため、５５℃、２０％の環境下の恒温槽に３、５、７日間保存し、保存する以前のサンプルと比較し、上記の感度評価及び印刷汚れ評価を行い長期保存の影響を比較評価した。
【０２８０】
【表４】

【０２８１】
【化４９】

【０２８２】
【化５０】

【０２８３】
【化５１】

【０２８４】
【化５２】

【０２８５】
【化５３】

【０２８６】
表４の結果より、本発明１３〜２２はいずれの試験においても良好な特性を有するが、本発明の好ましい光重合開始剤を用いた本発明１７〜１９は特に感度、保存安定性が良好であった。
【０２８７】
〔実施例４〕
本発明１３〜２２の感材を多量に作製し、表５の各現像液でランニング処理を行い、現像液を濾過しスラッジ量を測定した。
【０２８８】
（現像液組成）
Ａケイ酸カリ　　　　　　　　　　　　　　　　　　　　　　　　　８．０部
表５に示す界面活性剤（下記化合物）　　　　　　　　　　　　　　３．０部
苛性カリ　　　　　　　　　　　　　　　　　　ｐＨ＝１２．３となる添加量
《スラッジ》
各試料を１．５ｍ^２用意し、プレヒート及びプレ水洗を上記の自動現像機にて行い、オーバーコート層を除去後、１００ｍｌの上記現像液に２８℃３０秒間浸漬し、無補充で１．５ｍ^２処理した。現像液を濾過水洗し７０℃で１日間乾燥し、残渣をスラッジ量とした。結果を表５に記載する。
【０２８９】
【表５】

【０２９０】
【化５４】

【０２９１】
【化５５】

【０２９２】
表５の結果より、本発明の好ましい界面活性剤である、活性剤１、２を用いることにより、現像液中のスラッジ量が大幅に低減できることが分かった。
【０２９３】
〔実施例５〕
（本発明２３、２４）
本発明９の分光増感色素１及びトリアリールモノアルキルホウ素塩（昭和電工社製：Ｎ３Ｂ）を添加するかわりに、表６の化合物（下記化合物）を表６の添加量で添加し、オーバーコートは実施例１と同様にして本発明２３、２４を作製した。
【０２９４】
本発明２３、２４の感材を各々多量に作製し、自作のレーザー出力機、市販レーザーを複数個並べて光ファイバーで集光することで高出力化し、高速スピンミラーで１ｌｉｎｅを形成した後、実施例１と同様の現像処理を行い、レーザー光のスポット径：３０μｍと同じ線幅を再現できる露光エネルギーをゲル化エネルギーとした。
【０２９５】
結果を図１に記載する。図１はレーザー光波長が、４０５ｎｍ、４８８ｎｍ、及び５３２ｎｍの時に、各々版面光強度を変化させた場合のゲル化エネルギーを示した図である。
【０２９６】
この結果から、本発明の版面露光エネルギー範囲が特異的に好ましい事が分かる。また４０５ｎｍにおいては、露光出力が３０〜２００ｍＷが好ましく、特に好ましくは５０〜１５０ｍＷである事が分かる。同様に、５３２ｎｍにおいては、露光出力が１０〜１５０ｍＷが好ましく、特に好ましくは１０〜１２０ｍＷであり、カチオン染料＋ホウ素塩開始剤系は、露光波長の短波化に伴い高出力短時間記録が好ましい方向であることを見出した。
【０２９７】
【表６】

【０２９８】
【化５６】

【０２９９】
【発明の効果】
本発明により、高感度で、且つ耐刷性、保存安定性、汚れ性、スラッジに優れた感光性組成物及び平版印刷版、並びに平版印刷版の処理方法、画像形成方法を提供できた。
【図面の簡単な説明】
【図１】レーザー光波長を変化させた時の、版面光強度とゲル化エネルギーの関係を示した図である。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a photosensitive composition and a lithographic printing plate, and a method for processing a lithographic printing plate, and an image forming method. More specifically, the present invention has high sensitivity and excellent printing durability, storage stability, stainability, and sludge. The present invention relates to a photosensitive composition, a lithographic printing plate, a method for processing a lithographic printing plate, and an image forming method.
[0002]
[Prior art]
In general, in a lithographic printing plate, after exposing an image, the exposed portion is cured, and the unexposed portion is dissolved and removed, followed by washing with water and finisher gum to obtain a lithographic printing plate. In recent years, in order to obtain high resolution and sharpness, a method of producing a lithographic printing plate by performing digital exposure with laser light based on image information and then performing development processing has been studied. For example, a system that modulates an exposure light source with an image signal transmitted by a communication line or an output signal from an electronic plate making system, an image processing system, etc., and directly scans and exposes a photosensitive material to produce a lithographic printing plate. It is.
[0003]
However, the conventional lithographic printing plate material using a diazo resin has a problem that it is difficult to increase the sensitivity and the spectral sensitization method in accordance with the oscillation wavelength of laser light by digital exposure.
[0004]
In recent years, lithographic printing plate materials having a photopolymerizable photosensitive layer containing a photopolymerization initiator have attracted attention for digital exposure with laser light because of its ability to achieve high sensitivity suitable for laser light. A plate material for CTP (Computer To Plate) for recording digital data with the laser light source is required to have higher sensitivity for the purpose of performing recording in a short time.
[0005]
As a photopolymerization initiator used in a lithographic printing plate material having a photopolymerizable photosensitive layer containing a photopolymerization initiator, a radical is generated in an image-wise manner upon exposure, and the radical is used as a starting species. It is said that radical chain polymerization is suitable for image recording with high sensitivity.
[0006]
Cationic dyes and triarylmonoalkyl boron salt type photopolymerization initiators are known, for example, from JP-A-62-1430454, and can have spectral sensitivity according to the laser wavelength by selecting a cationic dye. As such, it is a preferred initiator. However, in a system that performs an alkali development treatment such as a photopolymerization type lithographic printing plate, storage stability in a recording material composition is poor, and the recording speed is not sufficient for high-speed recording with a laser. Had issues.
[0007]
On the other hand, analysis of the electron transfer reaction of the cationic dye and borate initiator system has been performed in various fields, and it is noted that storage stability can be improved by increasing the oxidation potential of the borate initiator, which is an electron donor type initiator. It is disclosed in Japanese Unexamined Patent Publication No. Hei 9-188686.
[0008]
Japanese Patent Application Laid-Open No. 9-188710 discloses that the sensitivity can be improved by introducing a bulky aryl group by ortho-substitution of an aryl group in a triaryl monoalkyl boron salt type photopolymerization initiator.
[0009]
These techniques are preferred methods, but when a borate initiator is used as a composition for a photosensitive lithographic printing plate by short-time laser exposure, sensitivity and printing durability are still insufficient, and stability is poor. Was not enough.
[0010]
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, and has as its object a highly sensitive photosensitive composition and a lithographic printing plate having excellent printing durability, storage stability, stainability, and sludge, and lithographic printing. An object of the present invention is to provide a plate processing method and an image forming method.
[0011]
Particularly, in combination with a tertiary amine monomer which is a preferred embodiment of the present invention, sensitivity, storage stability and printing durability are remarkably improved.
[0012]
[Means for Solving the Problems]
The above object of the present invention is achieved by the following configurations.
[0013]
1. It contains a boron salt compound represented by the general formula (1), a cationic dye, and a compound having an ethylenically unsaturated group, and 10 to 90% by mass of the compound having an ethylenically unsaturated group is a weight average. A photosensitive composition having a molecular weight of 15,000 to 200,000 and an acid value of 30 to 200 mg / KOH.
[0014]
2. The compound having an ethylenically unsaturated group has a weight average molecular weight of 20,000 to 200,000, an acid value of 30 to 200 mg / KOH, and a unit ratio having a reactive group contained in a repeating unit of the binder. The photosensitive composition according to the above item 1, wherein the content is 5 to 50%.
[0015]
3. It contains a boron salt compound represented by the general formula (1), a cationic dye, and a compound having an ethylenically unsaturated group, and the compound having the ethylenically unsaturated group is represented by the general formula (2) or A photosensitive composition containing a compound having an amide bond and a secondary or tertiary amine group in one molecule represented by the formula (3).
[0016]
4. 4. The photosensitive composition according to any one of items 1 to 3, wherein the cationic dye is at least one selected from indole-type cyanine, rhodamine, and safranine.
[0017]
5. The boron salt compound represented by the general formula (1) is a triarylmonoalkylboron salt and is a compound having a bulky substituent, wherein the boron salt compound is a compound having a bulky substituent. Photosensitive composition.
[0018]
6. The boron salt compound represented by the general formula (1) has two or more substituents, and at least two or more substituents at the 2- and 6-positions, and at least one of the substituents is an electron-withdrawing group. 6. The photosensitive composition according to any one of the above items 1 to 5, wherein
[0019]
7. The photosensitive composition according to any one of Items 1 to 6, wherein an oxidation potential of the boron salt compound represented by the general formula (1) is 0.3 to 0.7 V.
[0020]
8. The method according to any one of Items 1 to 7, further comprising at least one photopolymerization initiator selected from trihalomethyl compounds, metallocene compounds, N-phenylglycine, and onium salts. Photosensitive composition.
[0021]
9. The photosensitive composition according to any one of the above items 1 to 8, comprising at least one sensitizer selected from tertiary amine compounds, thiols, and thioketones.
[0022]
10. 10. A metal support having a surface roughness (Ra) of 0.2 to 0.7 [mu] m, which is electrically roughened in an acid medium and anodized, according to any one of the above items 1 to 9, A lithographic printing plate for laser recording comprising a layer containing a photosensitive composition and an oxygen barrier layer.
[0023]
11. 11. The lithographic printing plate for laser recording according to the item 10, wherein the metal support has a surface roughness (Ra) of 0.5 to 0.7 μm.
[0024]
12. 12. The lithographic printing plate for laser recording according to the item 10 or 11, wherein the metal support uses polyvinylphosphonic acid for post-treatment.
[0025]
13. 13. A processing method for exposing a lithographic printing plate for laser recording according to any one of the above 10 to 12 to laser exposure to form an image by an alkali developing treatment, wherein the pH of the alkali developing solution is 10.0 to 12. 5. A processing method, characterized in that:
[0026]
14． The alkali developer contains an inorganic alkali agent and a nonionic surfactant having a polyoxyalkylene ether group, and has a pH of 10.0 to 12.5 and a conductivity of 3 to 30 mS / cm. 14. The processing method according to the above 13, wherein
[0027]
15. The alkali developer contains an inorganic alkali agent and an anionic surfactant having a polyoxyalkylene ether group, and has a pH of 10.0 to 12.5 and a conductivity of 3 to 30 mS / cm. 14. The processing method according to the above 13, wherein
[0028]
16. 13. The image forming method according to claim 10, wherein the lithographic printing plate according to any one of items 10 to 12, is exposed to a laser beam of 200 to 600 nm, and is sequentially subjected to pre-washing and alkali development within 15 minutes after the exposure. Method.
[0029]
17. The lithographic printing plate according to any one of Items 10 to 12, wherein the lithographic printing plate is exposed to laser light of 200 to 600 nm, heated at 80 to 130 ° C. for 1 to 30 seconds within 15 minutes after exposure, pre-washed, alkali An image forming method comprising sequentially performing a development process.
[0030]
18. 18. The image forming method according to the above item 16 or 17, wherein recording is performed at a plate surface intensity of the laser light of 10 to 200 mW and a main scanning linear velocity of 200 to 2,000 m / sec.
[0031]
Hereinafter, details of the present invention will be described.
The photosensitive composition of the present invention contains at least a boron salt compound represented by the general formula (1), a cationic dye, and a compound having an ethylenically unsaturated group. In addition, resins that do not contain an ethylenically unsaturated group, activators, polymerization inhibitors, colorants, and the like can be appropriately used.
[0032]
(Compound containing ethylenically unsaturated group)
In the present invention, a part of the compound containing an ethylenically unsaturated group is preferably in any one of the following embodiments. These are effective as separate technologies, but it is more preferable to use them in combination.
[0033]
1) A compound having a weight average molecular weight of 15,000 to 200,000 and an acid value of 30 to 200 mg / KOH is contained in an amount of 10 to 90% by mass of the total amount of the compound having an ethylenically unsaturated group.
[0034]
2) The compound containing an ethylenically unsaturated group is a compound having an amide bond and a secondary or tertiary amine group in one molecule.
[0035]
By containing these compounds in the composition, the sensitivity and physical properties after curing of a system using a boron salt can be significantly improved.
[0036]
A specific description of 1) will be described below.
One form of the compound having an ethylenically unsaturated group preferably used in the present invention is a compound having a weight average molecular weight of 15,000 to 200,000 and an acid value of 30 to 200 mg / KOH. That is, the content of the compound having an unsaturated group is 10 to 90% by mass.
[0037]
As long as it is a compound having such a high molecular weight ethylenically unsaturated group, any conventionally known resin skeleton can be used. Of these, acrylic resins, urethane resins, polyester resins, and phenolic resins are preferred, and acrylic resins are particularly preferred.
[0038]
As for the method of introducing an ethylenically unsaturated group into the acrylic resin, a known method can be used without any particular limitation. For example, a method of reacting a glycidyl group with a carboxyl group described later, a method of reacting an isocyanate group with a hydroxyl group, and the like can be mentioned.
[0039]
Specifically, for example, allyl glycidyl ether, glycidyl (meth) acrylate, α-ethyl glycidyl (meth) acrylate, glycidyl crotonate, glycidyl isocrotonate, crotonyl may be added to the copolymer having a monomer unit having a carboxyl group. Aliphatic epoxy group-containing unsaturated compounds such as glycidyl ether, monoalkyl monoglycidyl itaconate, monoalkyl monoglycidyl fumarate, monoalkyl monoglycidyl maleate, and 3,4-epoxycyclohexylmethyl (meth) acrylate And the like. This is a reaction product obtained by reacting an unsaturated compound having an alicyclic epoxy group with the carboxyl group. In the present invention, the unit percentage is defined as the molar percentage of the carboxyl group and the epoxy group-containing unsaturated compound reacted, and the reacted unit is preferably from 5 to 50 mol%, particularly preferably from 10 to 30 mol%. . If it is less than 5 mol%, the sensitivity and printing durability are insufficient, and if it is more than 50 mol%, the preservability of the material itself tends to deteriorate, which is not preferable.
[0040]
In the present invention, the weight average molecular weight is a value measured by gel permeation chromatography (GPC).
[0041]
In the present invention, the acid value is the number of mg of potassium hydroxide required to neutralize 1 g of the compound. The acid value can be measured as follows. The sample is diluted 50-fold with methyl cellosolve and titrated with 0.1 mol / L potassium hydroxide. The inflection point of the pH curve obtained using a pH meter is defined as a neutralization point. The acid value is calculated from the amount of potassium hydroxide required to reach the neutralization point.
[0042]
The reaction between the copolymer having a carboxyl group-containing monomer unit and the epoxy group-containing unsaturated compound can be performed, for example, at a temperature of about 80 to 120 ° C. for about 1 to 50 hours. As a method for synthesizing the reaction product, it can be synthesized by a generally known polymerization method. R. Sorenson, T .; W. The method can be synthesized according to a method described in a document co-authored by Campbell and the like, a method described in patents such as JP-A-10-315598 and JP-A-11-271963, and the like, and the like.
[0043]
The addition amount of the compound having a high molecular weight ethylenically unsaturated group is preferably from 10 to 90% by mass, more preferably from 20 to 80% by mass, based on the total amount of the compound having an ethylenically unsaturated group. Particularly preferably, the content is 30 to 70% by mass. If the amount is less than 10% by mass or more than 90% by mass, the sensitivity and the printing durability are undesirably deteriorated.
[0044]
As the copolymer having a monomer unit having a carboxyl group, a vinyl copolymer having a monomer unit of an α, β-unsaturated carboxylic acid described in the following (5) as a constituent element is preferable. It is also preferable to contain a vinyl copolymer comprising at least one of the monomers described in (1) to (17).
[0045]
(1) Monomers having an aromatic hydroxyl group, for example, o- (or p-, m-) hydroxystyrene, o- (or p-, m-) hydroxyphenyl acrylate and the like.
[0046]
(2) Monomers having an aliphatic hydroxyl group, for example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, N-methylol acrylamide, N-methylol methacrylamide, 4-hydroxybutyl methacrylate, 5-hydroxypentyl acrylate, 5-hydroxypentyl Methacrylate, 6-hydroxyhexyl acrylate, 6-hydroxyhexyl methacrylate, N- (2-hydroxyethyl) acrylamide, N- (2-hydroxyethyl) methacrylamide, hydroxyethyl vinyl ether and the like.
[0047]
(3) Monomers having an aminosulfonyl group, for example, m- (or p-) aminosulfonylphenyl methacrylate, m- (or p-) aminosulfonylphenyl acrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- ( p-aminosulfonylphenyl) acrylamide and the like.
[0048]
(4) Monomers having a sulfonamide group, for example, N- (p-toluenesulfonyl) acrylamide, N- (p-toluenesulfonyl) methacrylamide and the like.
[0049]
(5) α, β-unsaturated carboxylic acids, for example, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, β-methacryloyloxyethyl hydrogen phthalate, β-methacryloyloxyethyl hydrogen succinate Nate.
[0050]
(6) Substituted or unsubstituted alkyl acrylates, for example, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, acrylic acid Decyl, undecyl acrylate, dodecyl acrylate, benzyl acrylate, cyclohexyl acrylate, 2-chloroethyl acrylate, N, N-dimethylaminoethyl acrylate, glycidyl acrylate and the like.
[0051]
(7) Substituted or unsubstituted alkyl methacrylates, for example, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate, methacrylic acid Decyl, undecyl methacrylate, dodecyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate, 2-chloroethyl methacrylate, N, N-dimethylaminoethyl methacrylate, glycidyl methacrylate and the like.
[0052]
(8) acrylamide or methacrylamides, for example, acrylamide, methacrylamide, N-ethylacrylamide, N-hexylacrylamide, N-cyclohexylacrylamide, N-phenylacrylamide, N- (4-nitrophenyl) acrylamide, N-ethyl-N -Phenylacrylamide, N- (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide and the like.
[0053]
(9) Monomers containing an alkyl fluoride group, for example, trifluoroethyl acrylate, trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, hexafluoropropyl methacrylate, octafluoropentyl acrylate, octafluoropentyl methacrylate, heptadecafluorodecyl methacrylate, N -Butyl-N- (2-acryloxyethyl) heptadecafluorooctylsulfonamide and the like.
[0054]
(10) Vinyl ethers, for example, ethyl vinyl ether, 2-chloroethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether and the like.
[0055]
(11) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate, and vinyl benzoate.
[0056]
(12) Styrenes, for example, styrene, methylstyrene, chloromethylstyrene and the like.
[0057]
(13) Vinyl ketones, for example, methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, phenyl vinyl ketone and the like.
[0058]
(14) Olefins, for example, ethylene, propylene, i-butylene, butadiene, isoprene and the like.
[0059]
(15) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine and the like.
[0060]
(16) Monomers having a cyano group, for example, acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethylacrylate, o- (or m-, p-) cyanostyrene and the like.
[0061]
(17) Monomers having an amino group, for example, N, N-diethylaminoethyl methacrylate, N, N-dimethylaminoethyl acrylate, N, N-dimethylaminoethyl methacrylate, polybutadiene urethane acrylate, N, N-dimethylaminopropyl acrylamide, N , N-dimethylacrylamide, acryloylmorpholine, Ni-propylacrylamide, N, N-diethylacrylamide and the like.
[0062]
Known monomers and prepolymers having a conventionally known ethylenically unsaturated group are preferably used in combination with the compound having a high molecular weight ethylenically unsaturated group. It is a particularly preferred embodiment of the present invention to use a compound having an amide bond and a secondary or tertiary amine group in one molecule described later in combination.
[0063]
Specific compounds include, for example, 2-ethylhexyl acrylate, 2-hydroxypropyl acrylate, glycerol acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, tetrahydrofurfuryloxyethyl acrylate, tetrahydrofurfuryloxyhexanol Monoacrylates such as acrylate, acrylate of ε-caprolactone adduct of 1,3-dioxane alcohol, and 1,3-dioxolane acrylate, or methacrylic acid in which these acrylates are replaced with methacrylate, itaconate, crotonate, and maleate , Itaconic acid, crotonic acid, maleic acid ester such as ethylene glycol diacrylate, triethylene Alcohol diacrylate, pentaerythritol diacrylate, hydroquinone diacrylate, resorcinol diacrylate, hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, diacrylate of neopentyl glycol hydroxypivalate, diacrylate of neopentyl glycol adipate Acrylate, diacrylate of ε-caprolactone adduct of neopentyl glycol hydroxypivalate, 2- (2-hydroxy-1,1-dimethylethyl) -5-hydroxymethyl-5-ethyl-1,3-dioxane diacrylate, Tricyclodecane dimethylol acrylate, ε-caprolactone adduct of tricyclodecane dimethylol acrylate, 1,6-hexanedi Acrylates such as diacrylates of diglycidyl ethers of phenols, or methacrylates, itaconic acids, croconates, methacrylates, itaconic acids, crotonic acids, maleates such as trimethylolpropane. Ε of triacrylate, ditrimethylolpropane tetraacrylate, trimethylolethane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, ε of dipentaerythritol hexaacrylate -Caprolactone adduct, pyrogallol triacrylate, propionic acid Polyfunctional acrylates such as pentaerythritol triacrylate, propionic acid / dipentaerythritol tetraacrylate, hydroxypivalyl aldehyde-modified dimethylolpropane triacrylate, and their EO modified products, or acrylates of these methacrylates, itaconates, crotonates And methacrylic acid, itaconic acid, crotonic acid, and maleic acid ester instead of maleate.
[0064]
Further, a prepolymer can be used in the same manner as described above. Examples of the prepolymer include the compounds described below, and a prepolymer obtained by introducing acrylic acid or methacrylic acid into an oligomer having an appropriate molecular weight and imparting photopolymerizability can also be suitably used. One or more of these prepolymers may be used in combination, or may be used as a mixture with the above-mentioned monomer or oligomer.
[0065]
As the prepolymer, for example, adipic acid, trimellitic acid, maleic acid, phthalic acid, terephthalic acid, hymic acid, malonic acid, succinic acid, glutaric acid, itaconic acid, pyromellitic acid, fumaric acid, glutaric acid, pimelic acid, Polybasic acids such as sebacic acid, dodecanoic acid and tetrahydrophthalic acid, and ethylene glycol, propylene glycol, diethylene glycol, propylene oxide, 1,4-butanediol, triethylene glycol, tetraethylene glycol, polyethylene glycol, glycerin and trimethylol Polyester obtained by introducing (meth) acrylic acid into a polyester obtained by bonding a polyhydric alcohol such as propane, pentaerythritol, sorbitol, 1,6-hexanediol, and 1,2,6-hexanetriol. Acrylates, for example, epoxy acrylates obtained by introducing (meth) acrylic acid into an epoxy resin such as bisphenol A / epichlorohydrin / (meth) acrylic acid and phenol novolak / epichlorohydrin / (meth) acrylic acid; for example, ethylene glycol / adipin Acid ・ tolylene diisocyanate ・ 2-hydroxyethyl acrylate, polyethylene glycol ・ tolylene diisocyanate ・ 2-hydroxyethyl acrylate, hydroxyethylphthalyl methacrylate ・ xylene diisocyanate, 1,2-polybutadiene glycol ・ tolylene diisocyanate ・ 2-hydroxyethyl acrylate Of trimethylolpropane / propylene glycol / tolylene diisocyanate / 2-hydroxyethyl acrylate As described above, urethane acrylate in which (meth) acrylic acid is introduced into urethane resin, for example, polysiloxane acrylate, silicone resin acrylates such as polysiloxane / diisocyanate / 2-hydroxyethyl acrylate, and (meth) acryloyl in oil-modified alkyd resin Examples include prepolymers such as alkyd-modified acrylates having introduced groups and spirane resin acrylates.
[0066]
The photosensitive lithographic printing plate material of the present invention and the photopolymerizable photosensitive layer of the photosensitive lithographic printing plate material used in the image forming method of the present invention include a phosphazene monomer, triethylene glycol, isocyanuric acid EO (ethylene oxide) -modified diacrylate. , Isocyanuric acid EO-modified triacrylate, dimethylol tricyclodecane diacrylate, trimethylolpropane acrylate benzoate, alkylene glycol-type acrylic acid-modified, urethane-modified acrylate, etc. It may contain addition polymerizable oligomers and prepolymers having structural units.
[0067]
Further, as an ethylenic monomer used in the photosensitive lithographic printing plate material of the present invention and the photosensitive lithographic printing plate material used in the image forming method of the present invention, a phosphate ester containing at least one (meth) acryloyl group Compounds. The compound is a compound in which at least a part of the hydroxyl group of phosphoric acid is esterified, and is not particularly limited as long as it has a (meth) acryloyl group.
[0068]
In addition, JP-A-58-212994, JP-A-61-6649, JP-A-62-46688, JP-A-62-48589, JP-A-62-173295, JP-A-62-187092, and JP-A-63-187092. Compounds described in JP-A-67189, JP-A-1-244891 and the like can be mentioned, and furthermore, "11290 Chemical Products", Chemical Daily, p. 286-294, "UV / EB curing handbook (raw material edition)", Polymer Publishing Association, p. The compounds described in 11 to 65 and the like can also be suitably used in the present invention. Of these, compounds having two or more acrylic or methacrylic groups in the molecule are preferred in the present invention, and those having a molecular weight of 10,000 or less, more preferably 5,000 or less are preferred.
[0069]
Here, the ethylenic double bond-containing monomer represented by the general formula (2), which is a compound having an amide bond and a secondary or tertiary amine group in one molecule, particularly preferably used in the present invention. explain.
[0070]
In the general formula (2), R ³ Represents a hydrogen atom, a methyl group or an ethyl group.
In the general formula (2), R ⁴ As the alkyl group represented by, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, iso-pentyl group, 2-ethylhexyl group, octyl group, decyl group, n-undecyl group, n-dodecyl Groups, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-docosadecyl group and the like.
[0071]
In the general formula (2), R ⁴ Examples of the hydroxyalkyl group represented by include a hydroxymethyl group, a hydroxyethyl group, a hydroxypropyl group, and a hydroxypentyl group.
[0072]
In the general formula (2), R ⁴ Examples of the aryl group represented by include a phenyl group and a naphthyl group.
[0073]
In the general formula (2), R ¹ And R ² Is an alkyl group represented by R ⁴ Has the same meaning as the alkyl group represented by
[0074]
In the general formula (2), R ¹ And R ² Examples of the alkoxyalkyl group represented by include a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, and a propoxyethyl group.
[0075]
In the general formula (2), X ¹ Examples of the divalent group having 2 to 12 carbon atoms represented by are a saturated hydrocarbon group, an arylene group and the like.
[0076]
In the general formula (2), X ¹ As a saturated hydrocarbon group having 2 to 12 carbon atoms represented by, for example, ethylene group, trimethylene group, tetramethylene group, propylene group, ethylethylene group, pentamethylene group, hexamethylene group, heptamethylene group Octamethylene group, nonamethylene group, decamethylene group, undecamethylene group, dodecamethylene group, cyclohexylene group (eg, 1,6-cyclohexanediyl group), cyclopentylene group (eg, 1,5-cyclopentanediyl) And the like).
[0077]
In the general formula (2), X ¹ Examples of the arylene group represented by include a phenylene group and a naphthylene group.
[0078]
In the general formula (2), X ² The divalent group represented by ¹ As a divalent group having 2 to 12 carbon atoms represented by the following, a saturated hydrocarbon group, an arylene group, or the like can be used. Those in which a methylene group is substituted by an oxygen atom can be used.
[0079]
In the general formula (2), X ² Is a trivalent group represented by X ² Is a divalent group (saturated hydrocarbon group, arylene group, etc.) further provided with one bonding group. For example, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group Yl group, heptanetriyl group, octanetriyl group, nonantriyl group, decanetriyl group, undecanetriyl group, dodecanetriyl group, cyclohexanetriyl group, cyclopentanetriyl group, benzenetriyl group, naphthalenetriyl group, etc. No.
[0080]
In the general formula (2), X ² The tetravalent group represented by ² Is a trivalent group represented by the general formula (1), further having one bonding group, for example, a propanediylidene group, a 1,3-propanediyl-2-ylidene group, a butanediylidene group, a pentanedylidene group, a hexanediylidene group. Group, heptanediylidene group, octanediylidene group, nonanediylidene group, decanediylidene group, undecanediylidene group, dodecanediylidene group, cyclohexanediylidene group, cyclopentanediylidene group, benzenetetrayl group, naphthalenetetrayl group, etc. No.
[0081]
X in general formula (2) ² In the above, examples of the alkyl group represented by Z include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, an iso-pentyl group, a 2-ethylhexyl group, an octyl group, and a decyl group.
[0082]
X in general formula (2) ² In the above, examples of the alkenyl group represented by Z include 2-propenyl group, 3-butenyl group, 1-methyl-3-propenyl group, 3-pentenyl group, 1-methyl-3-butenyl group, 4-hexenyl And the like.
[0083]
X in general formula (2) ² In the above, examples of the aryl group represented by Z include a phenyl group, an m-chlorophenyl group, a p-tolyl group, and a naphthyl group.
[0084]
X in general formula (2) ² In the above, examples of the halogen atom represented by Z include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
[0085]
X in general formula (2) ² In the above, examples of the alkoxyl group represented by Z include a methoxy group, an ethoxy group, a propoxy group, a butoxy group and the like.
[0086]
X in general formula (2) ² In the above, examples of the heterocyclic group represented by Z include a pyridyl group, a pyrrolyl group, a 2-methylpyrrolyl group, an indolyl group, an imidazolyl group, a furyl group, a thiazolyl group, and a pyrimidinyl group.
[0087]
In the general formula (2), D ¹ And D ² Examples of the divalent group having 1 to 5 carbon atoms represented by include a methylene group, a trimethylene group, a tetramethylene group, a propylene group, an ethylethylene group, a pentamethylene group, and a cyclopentylene group. .
[0088]
In the general formula (2), the divalent group having 2 to 12 carbon atoms represented by E is X ¹ Has the same meaning as a divalent group having 2 to 12 carbon atoms represented by
[0089]
In the general formula (2), a 5- to 7-membered heterocyclic ring represented by E and containing one or two types of atoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom As a heterocyclic ring constituting an aliphatic group having a substituent, for example, pyridine ring, furan ring, pyrrole ring, pyrazole ring, imidazole ring, oxazole ring, thiazole ring, pyrimidine ring, pyridazine ring, pyran ring, thiophene ring , Isoxazole ring, pyrroline ring, imidazoline ring, imidazolidine ring, pyrazolidine ring, pyrazoline ring, piperidine ring, piperazine ring, morpholine ring, quinuclidine ring and the like.
[0090]
Examples of the aliphatic group include a divalent group having 2 to 12 carbon atoms having a heterocyclic ring as described above, and the divalent group is represented by X ¹ Has the same meaning as a divalent group having 2 to 12 carbon atoms represented by
[0091]
In the general formula (2), examples of the arylene group having 6 to 12 carbon atoms represented by E include a phenylene group and a naphthylene group.
[0092]
In the general formula (2), examples of the aromatic heterocyclic ring constituting the aromatic heterocyclic group having a 5- or 6-membered ring represented by E include a furan ring, a pyrrole ring, a pyrazole ring, an imidazole ring, and an oxazole ring. , Thiazole ring, 1,2,3-oxadiazole ring, 1,2,3-triazole ring, 1,2,4-triazole ring, 1,3,4-thiadiazole ring, pyridine ring, pyridazine ring, pyrimidine ring , Pyrazine ring, s-triazine ring, benzofuran ring, indole ring, benzothiophene ring, benzimidazole ring, benzothiazole ring, purine ring, quinoline ring and isoquinoline ring.
[0093]
Here, each substituent represented by the above general formula (2) may further have a substituent.
[0094]
The compound represented by the general formula (2) can be synthesized with reference to a method well known to those skilled in the art, for example, a method described in US Pat. No. 2,509,288.
[0095]
Hereinafter, specific examples of the compound represented by Formula (2) will be given, but the present invention is not limited thereto.
[0096]
Embedded image

[0097]
Embedded image

[0098]
Embedded image

[0099]
Next, the ethylenic double bond-containing monomer represented by the general formula (3), which is preferably used in the present invention, will be described.
[0100]
In the general formula (3), R ⁸ May be different from each other when (g-f) is 2 or more. Compounds in which g and f have the same value are preferred. R ⁸ Is an alkyl group or a hydroxyalkyl group, preferably has 2 to 8 carbon atoms, more preferably 2 to 4 carbon atoms. R ⁸ Is preferably a monocyclic or bicyclic ring, more preferably a monocyclic ring, and may be substituted with an alkyl group, alkoxyalkyl group or halogen atom having up to 5 carbon atoms.
[0101]
R ⁵ And R ⁶ Is an alkyl group or an alkoxyalkyl group, preferably has 1 to 5 carbon atoms.
[0102]
R ⁷ Is preferably a methyl group.
D ³ And D ⁴ May be the same or different and are preferably a 6-membered saturated heterocycle containing two nitrogen atoms.
[0103]
When F is a saturated hydrocarbon group, it preferably has 2 to 6 carbon atoms; when F is an arylene group, a phenylene group is preferable; when F is a cycloaliphatic group, a cyclohexylene group is preferable; In the case of a group, a 5- or 6-membered ring containing a nitrogen atom or a sulfur atom is preferable.
[0104]
To obtain a compound represented by the general formula (3), Q ² Is N, and when n and m are the same value, glycidyl acrylate or alkyl acrylate is reacted with hydroxyalkylamine. Other compounds can be obtained in a similar manner.
[0105]
Specific examples of the compound represented by the general formula (3) of the present invention are shown below.
[0106]
Embedded image

[0107]
In the photosensitive lithographic printing plate material of the present invention and the photopolymerizable photosensitive layer of the photosensitive lithographic printing plate material used in the image forming method of the present invention, the compound containing an ethylenically unsaturated group described above is 5 to 5 in total. The content is preferably 99% by mass, more preferably 10 to 98% by mass, and particularly preferably 20 to 97% by mass.
[0108]
(Boron salt compound)
Examples of the organic borate salt compounds include organic borate compounds described in JP-A-62-143044, JP-A-9-188865, JP-A-9-188686, and JP-A-9-188710 (hereinafter referred to as "borate compounds"). Or a spectral sensitizing dye-based borate compound obtained from a cationic dye. Specific examples of the compound represented by the general formula (1) of the present invention are shown below, but the present invention is not limited thereto.
[0109]
Embedded image

[0110]
Embedded image

[0111]
Embedded image

[0112]
Embedded image

[0113]
Embedded image

[0114]
Embedded image

[0115]
Embedded image

[0116]
In the present invention, a boron salt having a particularly bulky substituent is preferable.
The term "bulky substituent" as used herein means, for example, a polycyclic, ie, a polycyclic aryl group, or simply a substituted aryl group. Examples of these are fused hydrocarbon rings, with or without heteroatoms, preferably S, O or N, such as 1- and 2-naphthyl, binaphthyl, anthracyl, phenanthryl, Pyrenyl, quinolyl and isoquinolyl groups. However, the term “bulky substituent” also means a ring arrangement, ie an aryl ring connected by a single bond. Examples are biphenyl, o-, m- or p-terphenyl or triphenylphenyl.
[0117]
The alkyl group having 1 to 20 carbon atoms is a linear or branched group, for example, an alkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 8 carbon atoms, an alkyl group having 1 to 6 carbon atoms or a carbon atom. It is an alkyl group having 1 to 4 atoms. For example, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, 2,4,4- Trimethyl-phenyl, 2-ethylhexyl, octyl, nonyl, decyl, undecyl, dodecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl or eicosyl.
[0118]
-O-, -S (O) p- or -NR ₅ A C 2 -C 20 alkyl group interrupted once or more times by-is, for example, 1 to 9 times, for example 1 to 7 times or 1 or 2 times, -O-, -S (O) p- or -NR ₅ -Has been interrupted. (R ₅ Represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a phenyl-alkyl group having 1 to 6 carbon atoms or a phenyl group, and the phenyl-alkyl group having 1 to 6 carbon atoms or the phenyl group is substituted. Represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or a group substituted 1 to 5 times by a halogen atom. This gives, for example, the following structural unit: -CH ₂ -O-CH ₃ , -CH ₂ CH ₂ -O-CH ₂ CH ₃ ,-[CH ₂ CH ₂ O] y-CH ₃ (Where y represents 1 to 9),-(CH ₂ CH ₂ O) ₇ CH ₂ CH ₃ , -CH ₂ -CH (CH ₃ ) -O-CH ₂ CH ₂ CH ₃ , -CH ₂ -CH (CH ₃ ) -O-CH ₂ CH ₂ , -CH ₂ SCH ₃ Or -CH ₂ -N (CH ₃ ) ₂ To form
[0119]
C3-C12 cycloalkyl is, for example, cyclopropyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclododecyl, especially cyclopentyl and cyclohexyl, preferably cyclohexyl. Examples of the C1-C8 alkenyl group which can be mono- or polysubstituted include, for example, allyl, methallyl, 1,1-dimethylallyl, 1-butenyl, 3-butenyl, 2-butenyl, 1,3 -A pentadienyl group, a 5-hexenyl group or a 7-octenyl group, especially an allyl group. R as an alkenyl group having 2 to 8 carbon atoms ₄ Is, for example, an alkenyl group having 2 to 6 carbon atoms, especially an alkenyl group having 2 to 4 carbon atoms.
[0120]
Phenyl-C 1 -C 6 alkyl is, for example, benzyl, phenylethyl, α-methylbenzyl, phenylpentyl, phenylhexyl or α, α-dimethylbenzyl, especially benzyl. Preference is given to phenyl-C1 -C4 alkyl, in particular phenyl -C1 -C2 alkyl. Substituted phenyl-C 1 -C 6 alkyl is substituted 1 to 4 times, for example 1, 2 or 3 times, especially 1 or 2 times on the phenyl ring.
[0121]
Phenyl-alkylene groups of 1 to 6 carbon atoms have two free bonds, one on the phenyl ring and the other on the alkylene group. That is,
[0122]
Embedded image

[0123]
(Where x represents 1 to 6).
A substituted phenyl group is substituted on the phenyl ring one to five times, for example once, twice or three times, especially once or twice. Substituents are, for example, at positions 2 and 6 of the phenyl ring, at positions 2 and 4 or at positions 2, 4 and 6, preferably at positions 2 and 6 or at positions 2, 4 and 6. Naphthyl-C1 -C3 alkyl is, for example, naphthylmethyl, naphthylethyl, naphthylpropyl or naphthyl-1-methylethyl, in particular naphthylmethyl. The alkyl unit can be at either the 1 or 2 position of the naphthyl ring system. The substituted naphthyl-C1 -C3 alkyl group is substituted on the aromatic ring one to four times, for example once, twice or three times, especially once or twice.
[0124]
The alkoxy group having 1 to 12 carbon atoms is a linear or branched group, for example, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butyloxy group, a sec-butyloxy group, an isobutyloxy group, a tert-butyloxy group. , Pentyloxy group, hexyloxy group, heptyloxy group, 2,4,4-trimethylpentyloxy group, 2-ethylhexyloxy group, octyloxy group, nonyloxy group, decyloxy group or dodecyloxy group, especially methoxy group and ethoxy group , A propoxy group, an isopropoxy group, an n-butyloxy group, a secondary butyloxy group, an isobutyloxy group, a tertiary butyloxy group, preferably a methoxy group.
[0125]
Halogen is fluorine, chlorine, bromine and iodine, especially chlorine, bromine and fluorine, preferably chlorine and fluorine. An alkyl group having 1 to 20 carbon atoms which is substituted by one or more halogen atoms is, for example, substituted on the alkyl group by 1 to 3 or 1 or 2 halogen substituents.
[0126]
Examples of divalent aromatic hydrocarbon groups include phenylene, stilbylene, biphenylene, o-, m- or p-terphenylene, triphenylphenylene, naphthylene, binaphthylene, anthracenylene, phenanthrylene, pyrenylene. Group, ferrosenylene group, furanylene group, thiophenylene group, pyridinylene group, quinolinylene group or isoquinonylene group.
[0127]
The naphthylene group is
[0128]
Embedded image

[0129]
In particular
[0130]
Embedded image

[0131]
It is. The stilbenylene group is
[0132]
Embedded image

[0133]
It is. The biphenylene group is
[0134]
Embedded image

[0135]
It is. An o-, m- or p-terphenylene group is
[0136]
Embedded image

[0137]
It is. The triphenylphenylene group is
[0138]
Embedded image

[0139]
It is. The binaphthylene group is
[0140]
Embedded image

[0141]
In particular,
[0142]
Embedded image

[0143]
It is. Anthracenylene group is
[0144]
Embedded image

[0145]
It is. The phenanthrylene group is
[0146]
Embedded image

[0147]
It is. The pyrenylene group is
[0148]
Embedded image

[0149]
It is. Furanylene group is
[0150]
Embedded image

[0151]
It is. The thiophenylene group is
[0152]
Embedded image

[0153]
It is. The pyridinylene group is
[0154]
Embedded image

[0155]
It is. The quinolinylene group is
[0156]
Embedded image

[0157]
It is. The isoquinonylene group is
[0158]
Embedded image

[0159]
It is. The 1,4-duryl group is
[0160]
Embedded image

[0161]
It is.
Substituted phenylene group, stilbenylene group, biphenylene group, o-, m- or p-terphenylene group, triphenylphenylene group, naphthylene group, binaphthylene group, anthracenylene group, phenanthrylene group, pyrenylene group, ferrosenylene group, furanylene group, The thiophenylene, pyridinylene, quinolinylene or isoquinonylene group is substituted one to four times, for example one, two or three times, especially one or two times. The substituents on the 1,4-phenylene ring are at the 2, 3, 5 or 6 positions, especially the 2 or 3 positions on the phenyl ring. Substituents on the 1,3-phenylene ring are at the 2, 4, 5 or 6 positions, especially the 4 or 5 positions on the phenyl ring.
[0162]
In particular, in the present invention, the substituent introduced into the aryl group preferably has any one of the following embodiments. Although these are effective as separate techniques, using them in combination is a more preferable embodiment.
[0163]
1) It is preferable that the aryl group bonded to boron has at least a substituent at the ortho position.
[0164]
2) It is preferable to introduce an electron-withdrawing group into the aryl group.
In the present invention, the electron-withdrawing group means a group having a positive σ value obtained by the effect of a substituent at the para-position according to the Hammett rule. Specific examples include nitro, nitroso, carbonyl, carboxyl, cyano, fluoroalkyl, phenyl, alkylsulfonyl, and halogen. Particularly preferred electron-withdrawing substituents in the present invention are phenyl, alkyl and halogens.
[0165]
A preferred embodiment of the present invention is to have at least a substituent at the ortho position of the aryl group, but it is also a preferred embodiment to have another substituent in addition to the ortho position. It is also an aspect of the present invention to have a substituent at a position other than the ortho position.
[0166]
In a preferred embodiment, the counter cation of the boron salt is a phosphorus compound as described in US Pat. No. 3,259,060.
[0167]
The boron salt compound particularly preferably used in the present invention preferably has an oxidation potential of 0 to 1.0 V, more preferably 0.3 to 0.7 V, and particularly preferably 0.4 to 0.65 V. Is preferred. Unlike the conventional technique that the sensitivity is low when the oxidation potential of the boron salt is high and the storage stability is deteriorated when the oxidation potential is low, in the present invention, the type and the number of additions of the above preferable electron-withdrawing groups are adjusted. By maintaining the oxidation potential in the above range and simultaneously introducing a substituent at the ortho position, it has been found that the sensitivity tends to be higher and the storage stability tends to be better than before. Along with such improvements, new problems such as deterioration of solubility in an alkali developing solution for a lithographic printing plate, contamination by developing scum, and shortening of the life of the developing solution have emerged. It was found that good developability was obtained by using, and good results were obtained from all viewpoints.
[0168]
The method for measuring the oxidation-reduction potential is as follows.
In the present invention, a working electrode: platinum, a comparative electrode: Ag / AgCl, and a counter electrode: platinum wire were used using a BAS100B electrochemical analyzer manufactured by BAS. As the supporting electrolyte, tetrabutylammonium perchlorate was used, and the measurement solvent was determined by dissolving the measurement substance in acetonitrile. In addition, since the conditions for obtaining the peak of the oxidation-reduction potential are obtained while setting for each sample, the description of the conditions is omitted.
[0169]
(Cationic dye)
In the present invention, an indole cyanine dye, a rhodamine dye having a specific structure, and a safranine dye having a specific structure are particularly preferable. The specific structure preferably does not have a structure such as an acid group, that is, a carboxylic acid group, a sulfonate group, and a phosphate group.
[0170]
Examples of suitable dyes as electron acceptors that can be added as co-initiators are described in U.S. Pat. No. 5,151,520. For example, a triarylmethane, such as malachite green, indoline, thiazine, such as methylene blue, xanthone, thioxanthone, oxazine, acridine or phenazine, such as safranine. As the auxiliary initiator, it is also possible to use the above-mentioned transition noble metal complex compound or onium ion compound. Cationic, neutral or anionic dyes can be used as auxiliary initiators for the new compounds. Particularly suitable cationic dyes are malachite green, methylene blue, safranin O, a compound represented by the general formula (4),
[0171]
Embedded image

[0172]
(Where R ₂ And R ′ represent an alkyl group or an aryl group, for example, rhodamine such as rhodamine B, rhodamine 6G or biolamin R), and sulforhodamine B or sulforhodamine G.
[0173]
Other suitable dyes are described, for example, by Neckers et al. Polym. Sci. , Part A, Poly. Chem. , 1995, 33, 1691-1703.
[0174]
Embedded image

[0175]
Is particularly advantageous.
Examples of other suitable dyes include compounds represented by general formula (5):
[0176]
Embedded image

[0177]
(Wherein R = alkyl group; n = 0, 1, 2, 3, or 4, and Y ₁ = CH = CH, N-CH ₃ , C (CH ₃ ) 2, O, S or Se) cyanine. Preferred cyanines are those of the above formula ₁ Is C (CH ₃ ) ₂ Or S.
[0178]
The following dye compounds are also suitable as auxiliary initiators.
[0179]
Embedded image

[0180]
Wherein Z represents P, S or N; ₃ Represents an alkyl group or an aryl group). Preferred compounds in the above formula are ⁺ R ₃ Is N (CH ₃ ) ₃ , N (C ₂ H ₅ ) ₃ Or P (C ₆ H ₅ ) ₃ It is what is.
[0181]
For example, Jag et al. Polym. Sci. Part A: Polymer Chem. 1992, 30, 1987 and Polymer 1993, 34 (6), 1130,
[0182]
Embedded image

[0183]
Or described in JP-A-7-70221,
[0184]
Embedded image

[0185]
Compounds of the formula wherein R 'represents an unsubstituted or substituted benzyl or phenacyl group are also suitable. The pyridinium compound may be substituted on the aromatic pyridinium ring.
[0186]
Other suitable dyes are found, for example, in U.S. Pat. No. 4,902,604. These are azulene dyes. Particularly suitable as co-initiators for the novel compounds are the compounds 1-18 listed in columns 10 and 11 of the above-mentioned patent specification. Examples of other suitable dyes are described in U.S. Pat. No. 4,950,581 at column 6, line 20 to column 9, line 57. Coumarin compounds can also be used as auxiliary initiators for new compounds and compositions. Examples of these are described in U.S. Pat. No. 4,950,581 at column 11, line 20 to column 12, line 42. Other suitable co-initiators are, for example, the xanthone or thioxanthone described in U.S. Pat. No. 4,950,581 at column 12, line 44 to column 13, line 15. Anionic dye compounds can also be used, for example, as auxiliary initiators. For example, rose bengal, eosin or fluorescein are also suitable. Other suitable dyes, for example from triarylmethanes or azos, are described, for example, in US Pat. No. 5,143,818.
[0187]
(Photopolymerization initiator)
As the photopolymerization initiator, a known photopolymerization initiator can be used in addition to the compound represented by the general formula (1) according to the present invention described above.
[0188]
For example, J. Carbonyl compounds, organic sulfur compounds, persulfides, redox compounds, azo and diazo compounds, halogen compounds, photoreducible dyes as described in Chapter 5 of "Light Sensitive Systems" by J. Kosar. And the like. Further specific compounds are disclosed in British Patent 1,459,563.
[0189]
That is, as a photopolymerization initiator, benzoin derivatives such as benzoin methyl ether, benzoin-i-propyl ether, α, α-dimethoxy-α-phenylacetophenone; benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate Benzophenone derivatives such as 4,4'-bis (dimethylamino) benzophenone; thioxanthone derivatives such as 2-chlorothioxanthone and 2-i-propylthioxanthone; anthraquinone derivatives such as 2-chloroanthraquinone and 2-methylanthraquinone; N-methyl Acridone derivatives such as acridone and N-butylacridone; α, α-diethoxyacetophenone, benzyl, fluorenone, xanthone, uranyl compounds, JP-B-59-1281, JP-B-61-9621, and JP Triazine derivatives described in JP-A-60-60104; Organic peroxides described in JP-A-59-1504 and JP-A-61-243807; JP-B-43-23684, JP-A-44-6413, JP-A-44-6413, and No. 47-1604 and diazonium compounds described in U.S. Pat. No. 3,567,453; organic azide compounds described in U.S. Pat. Nos. 2,848,328, 2,852,379 and 2,940,853; O-quinonediazides described in JP-A-36-22062, JP-A-37-13109, JP-A-38-18015, and JP-A-45-9610; JP-B-55-39162, JP-A-59-14023, and "Macromolecular ( Macromolecules) ", vol. 10, p. 1307 (1977); JP-A-59-1422. No. 5, azo compounds described in JP-A-1-54440, EP-A-109,851, EP-A-126,712, and "Journal of Imaging Science (J. Imag. Sci.)", Vol. (1986); a metal allene complex described in JP-A-5-213861 and JP-A-5-255347; an (oxo) sulfonium organoboron complex described in "Coordination Chemistry Review", Vol. 84, pp. 85-277. (1988) and a transition metal complex containing a transition metal such as ruthenium described in JP-A-2-182701; a 2,4,5-triarylimidazole dimer described in JP-A-3-209777; carbon tetrabromide And organic halo described in JP-A-59-107344. And the like.
[0190]
(Other additives)
In addition to the photopolymerization initiator, the photosensitive composition of the present invention may contain various additives.
[0191]
Examples of the sensitizer include a triazine compound described in JP-A-64-13140, an aromatic onium salt and an aromatic halonium salt described in JP-A-64-13141, and a sensitizer described in JP-A-64-13143. Organic peroxides include bisimidazole compounds and thiols described in JP-B-45-37377 and U.S. Pat. No. 3,652,275. The sensitizer is added in an amount of 10 parts by mass or less, preferably about 0.01 to 5 parts by mass, based on 100 parts by mass of the total of the photopolymerizable lipophilic thermoplastic monomer / prepolymer.
[0192]
Thermal inhibitors intended to prevent premature polymerization are, for example, hydroquinone, hydroquinone derivatives, p-methoxyphenol, β-naphthol or sterically hindered phenols, such as 2,6-di-tert-butyl-p-cresol. It is. To increase the storage stability in the dark, for example, copper compounds such as copper naphthenate, stearate or octoate, phosphorus compounds such as triphenylphosphine, tributylphosphine, triethylphosphite, triphenylphosphite or tribenzylphospho Fit, a quaternary ammonium compound, such as tetramethylammonium chloride or trimethylbenzylammonium chloride, or a hydroxylamine derivative, such as N-diethylhydroxylamine. It is also possible to add paraffin, or an equivalent wax-like substance, which does not dissolve sufficiently in the polymer to remove atmospheric oxygen during the polymerization and migrates to the surface at the beginning of the polymerization, forming a transparent surface layer which prevents air from entering. it can. Light stabilizers which can be added in small amounts are UV absorbers, for example of the hydroxyphenylbenzotriazole, hydroxyphenylbenzophenone, oxalamide or hydroxyphenyl-s-triazine type. These compounds can be used individually or in mixtures with or without sterically hindered amines (HALS).
[0193]
Examples of the ultraviolet absorber are as follows.
Examples of 1.2- (2'-hydroxyphenyl) benzotriazole: 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (3 ', 5'-di-tert-butyl-2' -Hydroxyphenyl) benzotriazole, 2- (5'-tert-butyl-2'-hydroxyphenyl) benzotriazole, 2- (2'-hydroxy-5 '-(1,1,3,3-tetramethylbutyl) Phenyl) benzotriazole, 2- (3 ', 5'-di-tert-butyl-2'-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3'-tert-butyl-2'-hydroxy-5' -Methylphenyl) -5-chlorobenzotriazole, 2- (3'-sec-butyl-5'-tert-butyl-2'-hydroxyphenyl) benzotriazole, 2- (2'-hydr Xy-4'-octyloxyphenyl) benzotriazole, 2- (3 ', 5'-di-tert-amyl-2'-hydroxyphenyl) benzotriazole, 2- (3', 5'-bis (α, α -Dimethylbenzyl) -2'-hydroxyphenyl) benzotriazole, 2- (3'-tert-butyl-2'-hydroxy-5 '-(2-octyloxycarbonylethyl) phenyl) -5-chlorobenzotriazole, -(3'-tert-butyl-5 '-[2- (2-ethylhexyloxy) carbonylethyl] -2'-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3'-tert-butyl-2' -Hydroxy-5 '-(2-methoxycarbonylethyl) phenyl) -5-chlorobenzotriazole, 2- (3'-tert-butyl-2'-hydroxy 5 '-(2-methoxycarbonylethyl) phenyl) benzotriazole, 2- (3'-tert-butyl-2'-hydroxy-5'-(2-octyloxycarbonylethyl) phenyl) benzotriazole, 2- (3 '-Tert-butyl-5'-[2- (2-ethylhexyloxy) carbonylethyl] -2'-hydroxyphenyl) benzotriazole, 2- (3'-dodecyl-2'-hydroxy-5'-methylphenyl) A mixture of benzotriazole and 2- (3'-tert-butyl-2'-hydroxy-5 '-(2-isooctyloxycarbonylethyl)) phenylbenzotriazole, 2,2'-methylenebis [4- (1,1 , 3,3-tetramethylbutyl) -6-benzotriazol-2-ylphenol]; 2- [3'-tert-butyl 5 '- (2-methoxycarbonylethyl) -2' transesterification of the hydroxyphenyl] -2H- benzotriazole with polyethylene glycol 300; following formula: [R-CH ₂ CH ₂ -COO (CH ₂ ) ₃ −] ₂ (Wherein R represents a 3'-tert-butyl-4'-hydroxy-5'-2H-benzotriazol-2-ylphenyl group).
[0194]
2.2 Examples of 2-hydroxy-benzophenones: 4-hydroxy, 4-methoxy-, 4-octyloxy-, 4-decyloxy-, 4-dodecyloxy-, 4-benzyloxy-, 4,2 ', 4' -Trihydroxy- and 2'-hydroxy-4,4'-dimethoxy derivatives.
[0195]
3. Examples of substituted and unsubstituted esters of benzoic acid: 4-tert-butylphenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoylresorcinol, bis (4-tert-butylbenzoyl) resorcinol, benzoyl Resorcinol, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl 3,5-di- Tertiary butyl-4-hydroxybenzoate, 2-methyl-4,6-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate.
[0196]
4. Examples of acrylates: ethyl α-cyano-β, β-diphenyl acrylate, isooctyl α-cyano-β, β-diphenyl-acrylate, methyl α-carbomethoxycinnamate, methyl α-cyano-β-methyl-p-methoxycinna Mate, butyl α-cyano-β-methyl-p-methoxycinnamate, methyl α-carbomethoxy-p-methoxycinnamate and N- (β-carbomethoxy-β-cyanovinyl) -2-methylindoline.
[0197]
5. Examples of sterically hindered amines: bis (2,2,6,6-tetramethylpiperidyl) sebacate, bis (2,2,6,6-tetramethyl-4-piperidyl) succinate, bis (1,2,2) 6,6-pentamethyl-4-piperidyl) sebacate, bis (1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-) 4-piperidyl) n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate, 1- (hydroxyethyl) -2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid With N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3 Condensation product with triazine, tris (2,2,6,6-tetramethyl-4-piperidyl) nitrilotriacetate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,2 3,4-butanetetraoate, 1,1 '-(1,2-ethanediyl) -bis (3,3,5,5-tetramethylpiperazinone), 4-benzoyl-2,2,6,6 -Tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, bis (1,2,2,6,6-pentamethylpiperidyl) -2-n-butyl-2- (2- (Hydroxy-3,5-di-tert-butylbenzyl) malonate, 3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro [4.5] decane-2,4- Zeon, bis (1-oct Ruoxy-2,2,6,6-tetramethylpiperidyl) sebacate, bis (1-octyloxy-2,2,6,6-tetramethylpiperidyl) succinate, N, N'-bis (2,2,6, 6-tetramethyl-4-piperidyl-4-piperidyl) condensation product of hexamethylenediamine and 4-morpholino-2,6-dichloro-1,3,5-triazine, 2-chloro-4,6-bis ( Condensation product of 4-n-butylamino-2,2,6,6-tetramethylpiperidyl) -1,3,5-triazine with 1,2-bis (3-aminopropylamino) ethane, 2-chloro -4,6-di (4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl) -1,3,5-triazine and 1,2-bis (3-aminopropylamino) ethane Condensation with 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro [4.5] decane-2,4-dione and 3-dodecyl-1- (1, 2,2,6,6-pentamethyl-4-piperidyl) pyrrolidine-2,5-dione.
[0198]
6. Examples of oxamides: 4,4'-dioctyloxyoxanilide, 2,2'-diethoxyoxanilide, 2,2'-dioctyloxy-5,5'-di-tert-butoxanilide, 2,2'- Didodecyloxy-5,5'-di-tert-butoxanilide, 2-ethoxy-2'-ethyloxanilide, N, N'-bis (3-dimethylaminopropyl) oxamide, 2-ethoxy-5-third Butyl-2'-ethoxylanide and mixtures of said compounds with 2-ethoxy-2'-ethyl-5,4'-di-tert-butoxanilide, mixtures of ortho- and para-methoxy-disubstituted oxanilides and o- and p -Mixtures of ethoxy-disubstituted oxanilides.
[0199]
7.2 Examples of 2- (2-hydroxyphenyl) -1,3,5-triazine: 2,4,6-tris (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2- (2-hydroxy-4-octyloxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- (2,4-dihydroxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2,4-bis (2-hydroxy-4-propyloxyphenyl) -6- (2,4-dimethylphenyl) -1,3,5 -Triazine, 2- (2-hydroxy-4-octyloxyphenyl) -4,6-bis (4-methylphenyl) -1,3,5-triazine, 2- (2-hydroxy-4-dodecyloxyphenyl) -4,6- (2,4-dimethylphenyl) -1,3,5-triazine, 2- (2-hydroxy-4-dodecyloxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,3 5-triazine, 2- [2-hydroxy-4- (2-hydroxy-3-butyloxypropoxy) phenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, -[2-hydroxy-4- (2-hydroxy-3-octyloxypropyloxy) phenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [4- (Dodecyloxy / tridecyloxy-2-hydroxypropoxy) -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine.
[0200]
8. Examples of phosphites and phosphonites: triphenyl phosphite, diphenylalkyl phosphite, phenyldialkyl phosphite, tris (nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris ( 2,4-di-tert-butylphenyl) phosphite, diisodecylpentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert. Butyl-4-methylphenyl) pentaerythritol diphosphite, diisodecyloxypentaerythritol diphosphite, bis (2,4-di-tert-butyl-6-methylphenyl) pentaerythritol diphosphite Bis (2,4,6-tris (tert-butylphenyl)) pentaerythritol diphosphite, tristearylsorbitol triphosphite, tetrakis (2,4-di-tert-butylphenyl) 4,4'-biphenylenediphospho Knight, 6-isooctyloxy-2,4,8,10-tetratert-butyl-12H-dibenzo [d, g] -1,3,2-dioxaphosphine, 6-fluoro-2,4,8 , 10-Tetra-tert-butyl-12-methyl-dibenzo [d, g] -1,3,2-dioxaphosphin, bis (2,4-di-tert-butyl-6-methylphenyl) methyl phosphite And bis (2,4-di-tert-butyl-6-methylphenyl) ethyl phosphite.
[0201]
To promote photopolymerization, it is possible to add amines such as triethanolamine, N-methyldiethanolamine, p-dimethylaminobenzoate or Michler's ketone. The action of amines can be enhanced by the addition of aromatic ketones of the benzophenone type. Examples of amines which can be used as oxygen scavengers are substituted N, N-dialkylanilines described in EP-A-339841. Other accelerators, co-initiators and autoxidants are, for example, thiols, thioethers, disulfides, phosphonium salts, phosphine oxides as described in EP-A-438123, BG-2180358 and JP-A-6-268309. Or phosphine. Photopolymerization is also promoted by adding other sensitizers that shift or extend the spectral sensitivity. They are in particular aromatic carbonyl compounds, such as benzophenone, thioxanthone, anthraquinone and 3-acylcoumarin derivatives, and / or 3- (aroylmethylene) thiazolines, but also eosin, rhodamine and erythrosine dyes.
[0202]
The curing step may be in particular with a colored composition (e.g. with titanium dioxide) and / or a component which forms free radicals under heating conditions, such as 2,2'-azobis (4-methoxy-2,4-dimethyl) valero By adding an azo compound such as a nitrile, a triazene, a diazosulfide, a pentazadiene or a peroxy compound, for example a hydroperoxide or a peroxycarbonate, for example tertiary butyl hydroperoxide as described in EP-A-245639. I can help.
[0203]
Other conventional additives, depending on the intended use, are optical brighteners, fillers, pigments, dyes, wetting agents or leveling agents. For curing thick and pigmented coatings, the addition of glass microspheres or powdered glass fibers as described in US Pat. No. 5,013,768 is suitable.
[0204]
(Protective layer: oxygen blocking layer)
It is preferable to provide a protective layer on the photopolymerizable photosensitive layer according to the invention. The protective layer (oxygen blocking layer) preferably has high solubility in a developing solution (generally an aqueous alkaline solution) described later, and specific examples thereof include polyvinyl alcohol and polyvinyl pyrrolidone. Polyvinyl alcohol has an effect of suppressing oxygen permeation, and polyvinyl pyrrolidone has an effect of securing adhesiveness with an adjacent photosensitive layer.
[0205]
In addition to the above two polymers, if necessary, polysaccharide, polyethylene glycol, gelatin, glue, casein, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, hydroxyethylstarch, gum arabic, saccharose octaacetate, ammonium alginate, sodium alginate And water-soluble polymers such as polyvinylamine, polyethylene oxide, polystyrenesulfonic acid, polyacrylic acid, and water-soluble polyamide.
[0206]
In the lithographic printing plate according to the present invention, the peeling force between the photosensitive layer and the protective layer is preferably at least 35 mN / mm, more preferably at least 50 mN / mm, even more preferably at least 75 mN / mm. Preferred protective layer compositions include those described in Japanese Patent Application No. 8-161645.
[0207]
The peeling force in the present invention is determined by applying an adhesive tape of a predetermined width having a sufficiently large adhesive force on the protective layer and peeling the adhesive tape together with the protective layer at an angle of 90 degrees with respect to the plane of the planographic printing plate material. It can be determined by measuring.
[0208]
The protective layer may further contain a surfactant, a matting agent, and the like, if necessary. The protective layer composition is dissolved in a suitable solvent, coated on the photosensitive layer and dried to form a protective layer. The main component of the coating solvent is particularly preferably water or alcohols such as methanol, ethanol, i-propanol and the like.
[0209]
The thickness of the protective layer is preferably from 0.1 to 5.0 μm, particularly preferably from 0.5 to 3.0 μm.
[0210]
(Support)
The support according to the present invention has a hydrophilic surface, for example, a metal plate of aluminum, stainless steel, chromium, nickel, or the like, or a plastic film such as a polyester film, a polyethylene film, or a polypropylene film laminated or deposited with the above-described metal thin film. A polyester film, a vinyl chloride film, a nylon film, etc. whose surface has been subjected to a hydrophilization treatment can be used, but an aluminum support is preferably used. In this case, pure aluminum or aluminum It may be an alloy.
[0211]
As the aluminum alloy of the support, various materials can be used, for example, an alloy of aluminum with a metal such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, nickel, titanium, sodium, or iron is used. .
[0212]
The support according to the present invention is preferably subjected to a degreasing treatment in order to remove the rolling oil on the surface prior to roughening (graining treatment). Examples of the degreasing treatment include a degreasing treatment using a solvent such as trichlene and thinner, and an emulsion degreasing treatment using an emulsion such as kesilon and triethanol. For the degreasing treatment, an aqueous solution of an alkali such as caustic soda can be used. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, dirt and oxide film that cannot be removed only by the above degreasing treatment can be removed. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, smut is formed on the surface of the support. In this case, the smut is immersed in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid, or a mixed acid thereof and desmutted. Preferably, a treatment is applied. Examples of the method of surface roughening include a mechanical method and a method of etching by electrolysis.
[0213]
The mechanical surface roughening method used is not particularly limited, but a brush polishing method and a honing polishing method are preferable. The surface roughening by the brush polishing method is performed, for example, by rotating a rotating brush using brush bristles having a diameter of 0.2 to 0.8 mm, and applying, for example, particles of volcanic ash having a particle size of 10 to 100 μm to water on the support surface. It can be performed by pressing a brush while supplying a uniformly dispersed slurry. For surface roughening by honing polishing, for example, particles of volcanic ash having a particle size of 10 to 100 μm are uniformly dispersed in water, pressure is applied from a nozzle to be ejected, and the surface is made to impinge obliquely on the support surface to perform surface roughening. Can be. Further, for example, abrasive particles having a particle size of 10 to 100 μm are formed on the surface of the support at an interval of 100 to 200 μm by 2.5 × 10 ³ -10 × 10 ³ Pieces / cm ² The sheets can be roughened by laminating the coated sheets so that the sheets are present at a density of 1 and transferring the rough surface pattern of the sheet by applying pressure.
[0214]
After the surface is roughened by the above-mentioned mechanical surface roughening method, it is preferable to immerse the substrate in an aqueous solution of an acid or an alkali in order to remove the abrasive, the formed aluminum dust and the like that have penetrated the surface of the support. As the acid, for example, sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid and the like are used, and as the base, for example, sodium hydroxide, potassium hydroxide and the like are used. Among these, it is preferable to use an aqueous alkali solution such as sodium hydroxide. The dissolution amount of aluminum on the surface is 0.5 to 5 g / m ² Is preferred. After performing the immersion treatment with an alkali aqueous solution, it is preferable to immerse in an acid such as phosphoric acid, nitric acid, sulfuric acid, and chromic acid or a mixed acid thereof to perform a neutralization treatment.
[0215]
Although the electrochemical surface roughening method is not particularly limited, a method of performing electrochemical surface roughening in an acidic electrolyte is preferable. As the acidic electrolytic solution, an acidic electrolytic solution usually used for an electrochemical surface roughening method can be used, but a hydrochloric acid-based or nitric acid-based electrolytic solution is preferably used. As the electrochemical surface roughening method, for example, the methods described in JP-B-48-28123, UK Patent 896,563, and JP-A-53-67507 can be used. This surface roughening method can be generally performed by applying a voltage in the range of 1 to 50 volts, but is preferably selected from the range of 10 to 30 volts. Current density is 10-200 A / dm ² Can be used, but 50 to 150 A / dm ² It is preferable to select from the range. Electricity is 100-5000 c / dm ² Can be used, but 100 to 2000 c / dm ² It is preferable to select from the range. The temperature for performing the surface roughening method can be in the range of 10 to 50 ° C, but is preferably selected from the range of 15 to 45 ° C.
[0216]
When performing electrochemical surface roughening using a nitric acid-based electrolyte as an electrolyte, it can be generally performed by applying a voltage in a range of 1 to 50 volts, but is selected from a range of 10 to 30 volts. Is preferred. Current density is 10-200 A / dm ² Can be used, but 20 to 100 A / dm ² It is preferable to select from the range. Electricity is 100-5000 c / dm ² Can be used, but 100 to 2000 c / dm ² It is preferable to select from the range. The temperature at which the electrochemical surface roughening method is performed can be in the range of 10 to 50 ° C, but is preferably selected from the range of 15 to 45 ° C. The nitric acid concentration in the electrolytic solution is preferably from 0.1 to 5% by mass. If necessary, nitrate, chloride, amines, aldehydes, phosphoric acid, chromic acid, boric acid, acetic acid, oxalic acid, and the like can be added to the electrolytic solution.
[0217]
When a hydrochloric acid-based electrolyte is used as the electrolyte, it can be generally applied by applying a voltage in the range of 1 to 50 volts, but is preferably selected from the range of 2 to 30 volts. Current density is 10-200 A / dm ² Can be used, but 50 to 150 A / dm ² It is preferable to select from the range. Electricity is 100-5000 c / dm ² Can be used, but 100 to 2000 c / dm ² , And 200-1000 c / dm ² It is preferable to select from the range. The temperature at which the electrochemical surface roughening method is performed can be in the range of 10 to 50 ° C, but is preferably selected from the range of 15 to 45 ° C. The concentration of hydrochloric acid in the electrolyte is preferably 0.1 to 5% by mass.
[0218]
After the surface is roughened by the above-mentioned electrochemical surface roughening method, it is preferable to immerse in an aqueous solution of an acid or alkali to remove aluminum dust and the like on the surface. As the acid, for example, sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid and the like are used, and as the base, for example, sodium hydroxide, potassium hydroxide and the like are used. Among these, it is preferable to use an aqueous alkali solution. The dissolution amount of aluminum on the surface is 0.5 to 5 g / m ² Is preferred. Further, it is preferable that after immersion treatment with an aqueous alkali solution, immersion in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof to perform neutralization treatment.
[0219]
The mechanical surface roughening method and the electrochemical surface roughening method may be used alone for roughening, or the mechanical surface roughening method may be followed by the electrochemical surface roughening method. The surface may be roughened.
[0220]
Subsequent to the roughening treatment, an anodic oxidation treatment can be performed. The method of the anodic oxidation treatment that can be used in the present invention is not particularly limited, and a known method can be used. By performing the anodic oxidation treatment, an oxide film is formed on the support. In the anodic oxidation treatment, an aqueous solution containing sulfuric acid and / or phosphoric acid at a concentration of 10 to 50% is used as an electrolytic solution, and the current density is 1 to 10 A / dm. ² A method of electrolysis at a high current density in sulfuric acid described in U.S. Pat. No. 1,412,768, and a method of electrolysis at high current density described in U.S. Pat. No. 3,511,661 are also used. And a method using a solution containing one or more of chromic acid, oxalic acid, malonic acid, and the like. The formed anodized coating amount is 1 to 50 mg / dm. ² Is suitable, and preferably 10 to 40 mg / dm. ² It is. The anodic oxidation coating amount is obtained, for example, by immersing an aluminum plate in a chromic acid phosphoric acid solution (prepared by dissolving 35 g of a 85% phosphoric acid solution and 20 g of chromium (IV) oxide in 1 L of water) to dissolve the oxide film, It can be determined by measuring the change in mass before and after dissolving the coating on the plate.
[0221]
The support subjected to the anodizing treatment may be subjected to a sealing treatment as required. These sealing treatments can be performed using a known method such as hot water treatment, boiling water treatment, steam treatment, sodium silicate treatment, dichromate aqueous solution treatment, nitrite treatment, and ammonium acetate treatment.
[0222]
The center line average roughness (Ra) of the surface of the support after the treatment is preferably 0.2 to 0.7 μm, and more preferably 0.5 to 0.7 μm.
[0223]
Furthermore, after performing these treatments, a water-soluble resin such as polyvinylphosphonic acid, a polymer and a copolymer having a sulfonic acid group in a side chain, polyacrylic acid, a water-soluble metal salt (eg, zinc borate) or Those coated with a yellow dye, an amine salt or the like are also suitable. Further, a sol-gel treated substrate having a functional group capable of causing an addition reaction by a radical covalently disclosed in JP-A-5-304358 is preferably used.
[0224]
(Application)
The prepared photosensitive composition (photosensitive layer coating solution) is applied on a support by a conventionally known method and dried to prepare a photosensitive lithographic printing plate material. Examples of the application method of the application liquid include an air doctor coater method, a blade coater method, a wire bar method, a knife coater method, a dip coater method, a reverse roll coater method, a gravure coater method, a cast coating method, a curtain coater method, an extrusion coater method, and the like. Can be mentioned.
[0225]
If the drying temperature of the photosensitive layer is too low, sufficient printing durability cannot be obtained, and if it is too high, not only Marangoni occurs but also fogging of non-image areas occurs. The preferred drying temperature range is 60 to 160 ° C, more preferably 80 to 140 ° C, and particularly preferably 90 to 120 ° C.
[0226]
(Image forming method)
Examples of the light source for imagewise exposing the lithographic printing plate according to the present invention include a laser, a light-emitting diode, a xenon lamp, a xenon flash lamp, a halogen lamp, a carbon arc lamp, a metal halide lamp, a tungsten lamp, a high-pressure mercury lamp, and an electrodeless light source. Can be mentioned.
[0227]
In the case of collective exposure, a mask material in which a negative pattern of a desired exposure image is formed of a light-shielding material may be overlaid on the photopolymerizable photosensitive layer and exposed.
[0228]
When using an array type light source such as a light emitting diode array, or when controlling the exposure of a light source such as a halogen lamp, a metal halide lamp, or a tungsten lamp with an optical shutter material such as a liquid crystal or PLZT, a digital signal corresponding to an image signal is used. Exposure is possible and preferred. In this case, writing can be performed directly without using a mask material.
[0229]
In the case of laser exposure, light can be squeezed into a beam to perform scanning exposure in accordance with image data, so that it is suitable for directly writing without using a mask material. When a laser is used as a light source, the exposure area can be easily reduced to a very small size, and high-resolution image formation is possible.
[0230]
As the laser light source, any of an argon laser, a He—Ne gas laser, a YAG laser, and a semiconductor laser can be suitably used. In the present invention, an InGaN-based or ZnSe-based material is used, It is particularly preferable to use a semiconductor laser capable of continuously oscillating in the 430 nm region in order to fully exhibit the effects of the present invention.
[0231]
Laser scanning methods include cylinder outer surface scanning, cylinder inner surface scanning, and plane scanning. In the cylindrical outer surface scanning, laser exposure is performed while rotating a drum around which a recording material is wound around the outer surface, and rotation of the drum is defined as main scanning and movement of laser light is defined as sub-scanning. In the cylindrical inner surface scanning, a recording material is fixed on the inner surface of the drum, a laser beam is irradiated from the inside, and a main scan is performed in the circumferential direction by rotating a part or all of the optical system, and a part of the optical system or Sub-scanning is performed in the axial direction by moving the whole linearly in parallel to the axis of the drum. In the planar scanning, the main scanning of the laser beam is performed by combining a polygon mirror or a galvanometer mirror with an fθ lens, and the sub-scanning is performed by moving the recording medium. The scanning of the outer surface of the cylinder and the scanning of the inner surface of the cylinder are easier to improve the precision of the optical system, and are suitable for high-density recording.
[0232]
It is known that in the boron salt + cationic dye initiator system, the cationic dye is decomposed and discolored by the generation of radicals by light irradiation. This reaction greatly differs depending on the light intensity. When the laser light plate surface intensity is less than 10 mW, the printing durability as required by the progress of the decomposition reaction is not obtained. It has been found that although the color reaction does not take precedence, the printing durability at the same exposure dose does not improve for some reason.
[0233]
It has also been found that this phenomenon is noticeable in that the exposure wavelength shifts to shorter wavelengths.
[0234]
(Development processing solution)
As the processing solution preferably used in the present invention, a conventional developer having a pH of 10.0 to 12.5 can be used without any particular limitation. The pH of the developer used in the present invention is from 10.0 to 12.5. However, if the pH is lower than the range, image formation cannot be performed. Problem arises. The preferred pH range is 10.5 to 12.5, and the particularly preferred range is 11.0 to 12.5.
[0235]
The conductivity of the developer used in the present invention is preferably from 3 to 30 mS / cm, but if it is lower, the elution of the photosensitive composition on the surface of the aluminum plate support usually becomes difficult, so that the printing is difficult. If it exceeds the range, the salt concentration is high, so that the elution rate of the photosensitive layer becomes extremely slow, and a residual film is formed in the unexposed area. The range of the conductivity is more preferably in the range of 5 to 20 mS / cm.
[0236]
As described above, the preferred boron salt compound of the present invention has remarkably reduced developability in an aqueous alkali solution, can dissolve or swell the non-image area of the photopolymerizable layer, and has a solubility in water at 20 ° C of 10% by mass or less. Organic solvents can be preferably used.
[0237]
Specific organic solvents include, for example, carboxylate esters such as ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl lactate and butyl repphosphate; ethyl butyl ketone, methyl isobutyl Ketones such as ketones and cyclohexanone; alcohols such as ethylene glycol monobutyl ether, ethylene glycol benzyl ether, ethylene glycol monophenyl ether, benzyl alcohol, methylphenylcarbinol, n-amyl alcohol and methyl amyl alcohol; alkyl substitution such as xylene Aromatic hydrocarbons; halogenated hydrocarbons such as methylene dichloride, ethylene dichloride and monochlorobenzene; and the like. Ether and benzyl alcohol are particularly preferred. The content of the organic solvent in the developer is about 1 to 20% by mass, and preferably 2 to 10% by mass.
[0238]
However, in recent years, there is a strong tendency that an organic solvent of a developer is disliked from an environmental point of view. From such a viewpoint, preferred development processing solutions of the present invention include those containing an alkali agent and a surfactant as essential components without using an organic solvent.
[0239]
Examples of the alkaline agent contained in the developer include sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium or ammonium phosphates of the second or tertiary origin, sodium metasilicate, sodium carbonate, carbonate Sodium hydrogen, potassium carbonate, ammonia, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanol Amines, triisopropanolamine, ethyleneimine, ethylenediamine and the like, preferably potassium silicate, sodium silicate, and sodium phosphate Potassium, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, monoethanolamine, diethanolamine, triethanolamine. The content of the alkali agent in the developer is usually about 0.05 to 8% by mass, preferably 0.5 to 6% by mass.
[0240]
As the surfactant, conventionally known compounds such as nonionic, anionic, cationic and amphoteric can be used without any particular limitation. In the present invention, nonionic and anionic surfactants are particularly preferred.
[0241]
Particularly preferred activators in the present invention are nonionic surfactants having a polyoxyalkylene ether group represented by the following general formula (6) and compounds in which terminal OH is substituted by an anion salt. It has been found that the use of these surfactants makes it possible to obtain good developability, stain due to developing scum, and extend the life of the developer.
[0242]
Embedded image

[0243]
(Where R ₁ Is an alkyl group having 3 to 15 carbon atoms which may have a substituent, an aromatic hydrocarbon group having 6 to 15 carbon atoms which may have a substituent, or 4 carbon atoms which may have a substituent To 15 heteroaromatic ring groups (substituents include an alkyl group having 1 to 20 carbon atoms, a halogen atom such as Br, Cl, and I; an aromatic hydrocarbon group having 6 to 15 carbon atoms; An aralkyl group having 17 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkoxy-carbonyl group having 2 to 20 carbon atoms, and an acyl group having 2 to 15 carbon atoms). ₂ Is an alkylene group having 1 to 100 carbon atoms which may have a substituent (here, examples of the substituent include an alkyl group having 1 to 20 carbon atoms and an aromatic hydrocarbon group having 6 to 15 carbon atoms). ), And n represents an integer of 1 to 100. )
Further, (R ₂ -O) _n May be two or three groups within the above range. Specific examples include those in which a combination of an ethyleneoxy group and a propyleneoxy group, an ethyleneoxy group and an isopropyloxy group, an ethyleneoxy group and a butyleneoxy group, and a combination of an ethyleneoxy group and an isobutylene group are randomly or blockwise. . In the present invention, the surfactant having a polyoxyalkylene ether group is used alone or in a complex system, and it is effective to add 1 to 30% by mass, preferably 2 to 20% by mass in a developer. If the addition amount is small, the developing property is reduced, while if it is too large, the development damage is increased, and the printing durability of the printing plate is reduced.
[0244]
Further, other surfactants described below may be added. Other surfactants include, for example, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, etc. Polyoxyethylene alkyl allyl ethers, polyoxyethylene alkyl esters such as polyoxyethylene stearate, sorbitan monolaurate, sorbitan monostearate, sorbitan distearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan triole Sorbitan alkyl esters such as ethate, monoglyceride alkyl esters such as glycerol monostearate and glycerol monooleate Nonionic surfactants such as sodium salt; alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate; alkylnaphthalene sulfonates such as sodium butylnaphthalenesulfonate, sodium pentylnaphthalenesulfonate, sodium hexylnaphthalenesulfonate, sodium octylnaphthalenesulfonate; Anionic surfactants such as alkyl sulfates such as sodium lauryl sulfate, alkyl sulfonates such as sodium dodecyl sulfonate, sulfosuccinates such as sodium dilauryl sulfosuccinate; alkyl betaines such as lauryl betaine and stearyl betaine; Amphoteric surfactants such as amino acids can be used, and particularly preferred are anionic surfactants such as alkylnaphthalene sulfonates. These surfactants can be used alone or in combination. The content of these surfactants in the developer is preferably from 0.1 to 20% by mass in terms of active ingredients.
[0245]
Further, in order to further improve the storage stability, printing durability, etc., a water-soluble sulfite such as sodium sulfite, potassium sulfite, lithium sulfite, magnesium sulfite or the like is used in an amount of about 0.05 to 4% by mass, preferably 0% by mass of the developer composition. It is preferred to incorporate it in a 0.1 to 1% by mass developer. Further, a solubilizing agent may be added to help dissolve the organic solvent in water.
[0246]
【Example】
Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited thereto. In the examples, “parts” represents “parts by mass” unless otherwise specified.
[0247]
[Example 1]
(Inventions 1 to 4, Comparative Examples 1 to 5)
(Synthesis of binder)
In a three-necked flask under a nitrogen stream, 46.0 parts (0.46 mol) of methyl methacrylate (the following compound 1), 41.4 parts (0.48 mol) of methacrylic acid (the following compound 2), and ethyl methacrylate (the following compound). Compound 3) 6.7 parts (0.06 mol), 100 parts of ethanol and 1.23 parts of α, α'-azobisisobutyronitrile were added, and reacted in an oil bath at 80 ° C. for 6 hours in a nitrogen stream. A high polymer was obtained. Thereafter, 1 part of triethylbenzylammonium chloride and 42.5 parts (0.3 mol) of glycidyl methacrylate (epoxy group-containing unsaturated compound: the following compound 4) were added to the polymer and reacted at a temperature of 25 ° C. for 3 hours. Thus, a synthetic binder A (compound 5 shown below) was obtained. The weight average molecular weight measured using GPC was about 70,000.
[0248]
Hereinafter, the monomer unit ratio and the ratio of the epoxy group-containing unsaturated compound to be reacted with the carboxyl group shown in Table 1 are changed by changing the charged amount, and the weight average molecular weight is adjusted by adjusting the reaction time of the polymer. By changing and performing the same operation, synthetic binders A to G were obtained.
[0249]
[Table 1]

[0250]
Embedded image

[0251]
Embedded image

[0252]
Embedded image

[0253]
Embedded image

[0254]
Embedded image

[0255]
(Preparation of support)
A 0.24 mm-thick aluminum plate (material 1050, tempered H16) was immersed in a 5% aqueous sodium hydroxide solution maintained at 65 ° C., subjected to a 1-minute degreasing treatment, and then washed with water. The degreased aluminum plate was immersed in a 10% hydrochloric acid aqueous solution maintained at 25 ° C. for 1 minute to neutralize, and then washed with water. Next, this aluminum plate was placed in a 0.3% by mass aqueous hydrochloric acid solution at 25 ° C. and a current density of 100 A / dm. ² After the electrolytic surface roughening was performed with an alternating current for 60 seconds under the conditions described above, a desmut treatment was performed for 10 seconds in a 5% aqueous sodium hydroxide solution kept at 60 ° C. The surface-roughened aluminum plate subjected to desmut treatment is placed in a 15% sulfuric acid solution at 25 ° C. and a current density of 10 A / dm. ² Anodizing treatment was performed for 1 minute under the conditions of a voltage of 15 V and sealing treatment was performed at 90 ° C. with 3% sodium silicate to prepare a support. At this time, the center line average roughness (Ra) of the surface was 0.65 μm.
[0256]
(Surface treatment of support)
The above-prepared support was immersed in the following solution for treatment.
[0257]
Solution temperature 80 ℃
Vinylphosphonic acid 0.2% by mass
Polyvinylphosphonic acid 1.5% by mass
An aluminum plate was passed through the above solution for 30 seconds and dried.
[0258]
(Preparation of lithographic printing plate material)
On the above-mentioned surface-treated support, a coating solution of a photopolymerizable photosensitive layer having the following composition was dried at 2.0 g / m 2. ² And dried at 95 ° C. for 1.5 minutes. Thereafter, an overcoat layer coating solution having the following composition was further dried on the photosensitive layer at a rate of 2.0 g / m 2 when dried. ² And dried at 75 ° C. for 1.5 minutes to prepare a lithographic printing plate material having an overcoat layer on the photosensitive layer.
[0259]
The coated surface of the photosensitive layer was contacted with a metal roller (SUS) at a linear pressure of 29.4 N, and it was confirmed whether the photosensitive layer was transferred to SUS.
[0260]

[0261]
(Image formation)
Using the CTP exposure apparatus (Tigercat: ECRM) equipped with an FD-YAG laser light source, the photopolymerizable lithographic printing plate material thus produced was 2540 dpi (dpi is dots per inch or 2.54 cm). (Representing a number). Next, before development, a heating unit, a washing unit for removing the overcoat layer, a developing unit filled with the following developer composition, a washing unit for removing the developing solution attached to the plate surface, a gum solution for protecting the image area ( Developing process was carried out using a CTP automatic developing machine (PHW23-V: manufactured by Technigraph) equipped with GW-3: manufactured by Mitsubishi Chemical Co., Ltd. (2 times dilution), and the lithographic plates of the inventions 1-4 and Comparative Examples 1-5. A printing plate was obtained. At this time, the heating device was set so that the plate surface temperature was 115 ° C. and the plate residence time was 15 seconds. After the exposure, the plate was inserted into the heating unit of the automatic processing machine within 60 seconds.
[0262]
(Developer composition)
A Potassium silicate (potassium silicate) 8.0% by mass
Perex NBL: 3.0% by mass manufactured by Kao Corporation
Caustic potash Adjusted to pH = 12.3
(Evaluation of lithographic printing plate)
The lithographic printing plate obtained as described above was evaluated as follows.
[0263]
"sensitivity"
The exposure energy of the laser was changed, and a 100% solid image density was measured for each exposure energy. A point at a reflection density of -10% from the highest solid density was defined as the lowest image forming energy = sensitivity.
[0264]
《Dirt》
After continuous printing of 1,000 sheets, the printing plate was wiped with a cleaner, printing was resumed after 15 minutes, and it was visually determined whether or not the stain disappeared within 50 sheets.
[0265]
《Storage stability》
In order to forcibly degrade the photopolymerizable lithographic printing plate material, store it in a thermostat at 55 ° C and 20% for 3 days, compare it with the sample before storage, evaluate the sensitivity above and compare the effect of storage evaluated.
[0266]
The results are all shown in Table 2.
[0267]
[Table 2]

[0268]
Embedded image

[0269]
From the results in Table 2, it was found that, among the photosensitive lithographic printing plate materials on which images were formed, the present inventions 1 to 4 were superior in tack, sensitivity, stain, and storage stability to the comparative examples.
[0270]
[Example 2]
(Inventions 5 to 12, Comparative Examples 6 to 8)
The preparation of the support and the surface treatment were performed in the same manner as in Example 1. The binder was selected from those prepared above and used.
[0271]
(Undercoat layer to support)
The undercoat layer coating solution having the following composition was dried on the support at a rate of 0.2 g / m2 when dried. ² Was applied with a wire bar and subjected to a heat treatment at 100 ° C. for 3 minutes to prepare a support having been undercoated.
[0272]
(Coating solution for undercoat layer)
1 part of γ-methacryloxypropyltrimethoxysilane
80 parts of methyl ethyl ketone
Cyclohexanone 19 parts
(Preparation of lithographic printing plate material)
On the undercoated support, a lithographic printing plate material having an overcoat layer on the photosensitive layer was prepared in the same manner as in Example 1 except that the coating liquid for the photopolymerizable photosensitive layer having the following composition was used. did.
[0273]

[0274]
The same operation as in Example 1 was performed to form an image, and the planographic printing plate was evaluated. Table 3 shows the evaluation results. In Table 3, the following printing durability evaluation was also evaluated.
[0275]
《Printing durability》
A lithographic printing plate prepared by exposing and developing an image of 175 lines at an appropriate exposure amount was coated on a printing press (DAIYA1F-1 manufactured by Mitsubishi Heavy Industries, Ltd.) with coated paper and printing ink (Toyo King manufactured by Toyo Ink Co., Ltd.). Printing was performed using High Echo M Red and a fountain solution (H-solution SG-51, 1.5% concentration, manufactured by Tokyo Ink Co., Ltd.). The number of generated prints was used as an index of printing durability.
[0276]
[Table 3]

[0277]
From the results in Table 3, Examples 5 to 12 of the present invention are excellent in tack, sensitivity, stain, storage stability and printing durability, and particularly, Examples 9 to 12 of the present invention using compound A as a tertiary amine monomer are: It was found that the sensitivity, storage stability and printing durability were significantly improved.
[0278]
[Example 3]
(Invention 13-22)
Instead of adding the spectral sensitizing dye 1 of the present invention 5 and a triarylmonoalkylboron salt (N3B manufactured by Showa Denko KK), the compounds shown in Table 4 (the following compounds) were added in the amounts shown in Table 4, and overcoating was performed. Prepared inventions 13 to 22 in the same manner as invention 5.
[0279]
《Storage stability》
In order to forcibly degrade the photopolymerizable lithographic printing plate material, store it in a thermostat at 55 ° C and 20% for 3, 5 and 7 days. Evaluation was performed and the effects of long-term storage were compared and evaluated.
[0280]
[Table 4]

[0281]
Embedded image

[0282]
Embedded image

[0283]
Embedded image

[0284]
Embedded image

[0285]
Embedded image

[0286]
From the results in Table 4, the inventions 13 to 22 have good properties in any of the tests, but the inventions 17 to 19 using the preferred photopolymerization initiator of the invention have particularly good sensitivity and storage stability. there were.
[0287]
[Example 4]
The photosensitive materials of the inventions 13 to 22 were prepared in a large amount, subjected to a running treatment with each of the developing solutions shown in Table 5, filtered, and the amount of sludge was measured.
[0288]
(Developer composition)
A-potassium silicate 8.0 parts
3.0 parts of a surfactant (the following compound) shown in Table 5
Caustic potash pH = 12.3
《Sludge》
1.5 m for each sample ² Prepared, pre-heated and pre-washed with the above-mentioned automatic developing machine, after removing the overcoat layer, immersed in 100 ml of the above-mentioned developer for 30 seconds at 28 ° C. ² Processed. The developer was washed with filtered water and dried at 70 ° C. for 1 day, and the residue was used as sludge amount. Table 5 shows the results.
[0289]
[Table 5]

[0290]
Embedded image

[0291]
Embedded image

[0292]
From the results in Table 5, it was found that the use of Activators 1 and 2, which are preferred surfactants of the present invention, can significantly reduce the amount of sludge in the developer.
[0293]
[Example 5]
(Invention 23, 24)
Instead of adding the spectral sensitizing dye 1 of the present invention 9 and a triarylmonoalkylboron salt (manufactured by Showa Denko KK: N3B), the compounds shown in Table 6 (the following compounds) were added in the amounts shown in Table 6 and overcoated. In the same manner as in Example 1, inventions 23 and 24 were produced.
[0294]
After producing a large amount of the photosensitive materials of the present inventions 23 and 24, a self-made laser output device, a plurality of commercially available lasers were arranged side by side and condensed by an optical fiber to increase the output, and one line was formed by a high-speed spin mirror. The same developing treatment as in No. 1 was performed, and the exposure energy capable of reproducing the same line width as the laser beam spot diameter: 30 μm was defined as the gelling energy.
[0295]
The results are shown in FIG. FIG. 1 is a diagram showing the gelation energy when the plate surface light intensity is changed when the laser light wavelength is 405 nm, 488 nm, and 532 nm.
[0296]
From these results, it can be seen that the plate exposure energy range of the present invention is specifically preferable. At 405 nm, the exposure output is preferably from 30 to 200 mW, and particularly preferably from 50 to 150 mW. Similarly, at 532 nm, the exposure output is preferably from 10 to 150 mW, particularly preferably from 10 to 120 mW. In the cationic dye + boron salt initiator system, high-output short-time recording is preferred with shortening of the exposure wavelength. Was found.
[0297]
[Table 6]

[0298]
Embedded image

[0299]
【The invention's effect】
According to the present invention, a photosensitive composition and a lithographic printing plate having high sensitivity and excellent in printing durability, storage stability, stain resistance, and sludge, a lithographic printing plate processing method, and an image forming method can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram showing a relationship between plate surface light intensity and gelling energy when a laser light wavelength is changed.

Claims (18)

It contains a boron salt compound represented by the following general formula (1), a cationic dye, and a compound having an ethylenically unsaturated group, and 10 to 90% by mass of the compound having an ethylenically unsaturated group is a weight average. A photosensitive composition having a molecular weight of 15,000 to 200,000 and an acid value of 30 to 200 mg / KOH.

(Wherein _{R 1,} R 2, _{R 3} and _{R 4} are each independently an alkyl group, an aryl group, an aralkyl group, an alkenyl group, an alkynyl group, a silyl group, a heterocyclic group, or a halogen atom, ^{Z +} is Indicates any cation.) The compound having an ethylenically unsaturated group has a weight average molecular weight of 20,000 to 200,000, an acid value of 30 to 200 mg / KOH, and a unit ratio having a reactive group contained in a repeating unit of the binder. The photosensitive composition according to claim 1, wherein the content is 5 to 50%. It contains a boron salt compound represented by the general formula (1), a cationic dye, and a compound having an ethylenically unsaturated group, and the compound having an ethylenically unsaturated group is represented by the following general formula (2) or A photosensitive composition comprising a compound having an amide bond and a secondary or tertiary amine group in one molecule represented by the formula (3).

(Where Q ¹ is

Or -S-, R ⁴ represents an alkyl group, a hydroxyalkyl group or an aryl group, R ¹ and R ² each represent a hydrogen atom, an alkyl group or an alkoxyalkyl group, and R ³ represents a hydrogen atom, a methyl group or Represents an ethyl group, X ¹ represents a divalent group having 2 to 12 carbon atoms, X ² represents a divalent group to a tetravalent group, or

And Z represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a halogen atom, an alkoxyl group, or a heterocyclic group, p represents an integer of 1 to 4, and q represents an integer of 1 to 3. D ¹ and D ² each represent a divalent group having 1 to 5 carbon atoms, and E is a divalent group having 2 to 12 carbon atoms, a 5-membered ring to a 7-membered ring. An aliphatic group having a heterocyclic ring containing one or two kinds of atoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom, an arylene group having 6 to 12 carbon atoms, or a 5-membered ring Or represents an aromatic heterocyclic group having a 6-membered ring, a represents 0 or an integer of 1 to 4, b represents 0 or 1, c represents an integer of 1 to 3, and m represents an atom of Q ¹ The valence represents an integer of 2 to 4, n represents an integer of 1 to m, and all groups having the same definition can be the same or different from each other. )

(Where Q ² is

R ⁸ represents an alkyl group, a hydroxyalkyl group or an aryl group, R ⁵ and R ⁶ each represent a hydrogen atom, an alkyl group or an alkoxyalkyl group, and R ⁷ represents a hydrogen atom, a methyl group or an ethyl group. , D ³ and D ⁴ each represent a saturated hydrocarbon group having 1 to 5 carbon atoms, F represents a saturated hydrocarbon group having 2 to 12 carbon atoms, and 5 to 7 membered rings And a cycloaliphatic group containing up to two N, O or S atoms as member rings, an arylene group having 6 to 12 carbon atoms, or a heterocyclic aromatic group having 5 to 6 member rings the stands, d and e is an integer of 1 to 4, g represents an integer of 2 to 4 by the valency of Q ^2, f represents an integer of 1-g, all groups of the same definition mutually It can be the same or different. ) The photosensitive composition according to any one of claims 1 to 3, wherein the cationic dye is at least one selected from indole-type cyanine, rhodamine, and safranine. The boron salt compound represented by the general formula (1) is a triaryl monoalkyl boron salt and is a compound having a bulky substituent. The method according to any one of claims 1 to 4, wherein the boron salt compound is a compound having a bulky substituent. Photosensitive composition. The boron salt compound represented by the general formula (1) has two or more substituents, and at least two or more substituents at positions 2, and at least one of the substituents has an electron-withdrawing group. The photosensitive composition according to any one of claims 1 to 5, wherein The photosensitive composition according to any one of claims 1 to 6, wherein an oxidation potential of the boron salt compound represented by the general formula (1) is 0.3 to 0.7 V. The composition according to claim 1, further comprising at least one photopolymerization initiator selected from a trihalomethyl compound, a metallocene compound, N-phenylglycine, and an onium salt. 9. Photosensitive composition. The photosensitive composition according to any one of claims 1 to 8, further comprising at least one sensitizer selected from a tertiary amine compound, a thiol, and a thioketone. The metal support according to any one of claims 1 to 9, wherein the metal support is electrically roughened in an acid medium and has an anodized surface roughness (Ra) of 0.2 to 0.7 µm. A lithographic printing plate for laser recording comprising a layer containing a photosensitive composition and an oxygen barrier layer. The lithographic printing plate for laser recording according to claim 10, wherein the metal support has a surface roughness (Ra) of 0.5 to 0.7 m. The lithographic printing plate for laser recording according to claim 10, wherein the metal support uses polyvinyl phosphonic acid for post-treatment. A method for forming an image by laser exposure of the lithographic printing plate for laser recording according to any one of claims 10 to 12 to form an image by an alkali development treatment, wherein the pH of the alkali developer is from 10.0 to 10. 12.5. The alkali developer contains an inorganic alkali agent and a nonionic surfactant having a polyoxyalkylene ether group, and has a pH of 10.0 to 12.5 and a conductivity of 3 to 30 mS / cm. 14. The processing method according to claim 13, wherein The alkali developer contains an inorganic alkali agent and an anionic surfactant having a polyoxyalkylene ether group, and has a pH of 10.0 to 12.5 and a conductivity of 3 to 30 mS / cm. 14. The processing method according to claim 13, wherein An image characterized in that the lithographic printing plate according to any one of claims 10 to 12 is exposed to a laser beam of 200 to 600 nm, and is sequentially subjected to pre-washing and alkali development within 15 minutes after exposure. Forming method. The lithographic printing plate according to any one of claims 10 to 12, is exposed to a laser beam of 200 to 600 nm, heated at 80 to 130 ° C for 1 to 30 seconds within 15 minutes after exposure, pre-washed, An image forming method comprising sequentially performing an alkali developing treatment. 18. The image forming method according to claim 16, wherein recording is performed at a plate surface intensity of the laser light of 10 to 200 mW and a main scanning linear velocity of 200 to 2,000 m / sec.

Images