JP2005010264A - Method for processing photosensitive lithographic printing plate and method for decreasing deterioration of developing solution - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for processing a photosensitive lithographic printing plate and a method for decreasing deterioration in a developing solution, by which the development stability of the developing solution is maintained and problems relating to the increase in the cost due to increase in the amount of use of a replenisher liquid or the increase in a waste liquid are simultaneously solved, ink contamination in a non-image part is improved, and production of sludge is suppressed. <P>SOLUTION: The method for decreasing deterioration in the developing solution is carried out by replacing air which is forcibly brought into contact with the waste liquid of an aqueous alkaline developing solution containing substantially no silicate by the air in a developing tank which houses an aqueous alkali developing solution containing substantially no silicate. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００４２】
好ましくは、２−ヒドロキシエチルメタクリレート、２−ヒドロキシエチルアクリレート、４−ヒドロキシブチルアクリレート、２−ヒドロキシプロピレン−１，３−ジメタクリレート、２−ヒドロキシプロピレン−１−メタクリレート−３−アクリレート等が挙げられる。
【００４３】
これらの反応は、通常のジオール化合物、ジイソシアネート化合物、ヒドロキシル基含有アクリレート化合物の反応で、ウレタンアクリレートを合成する方法と同様に行うことが出来る。
【００４４】
また、これらの分子内に三級アミノ基を含有する多価アルコール、ジイソシアネート化合物、および分子内にヒドロキシル基と付加重合可能なエチレン性二重結合を含有する化合物の反応生成物において具体例を以下に示す。
【００４５】
Ｍ−１：トリエタノールアミン（１モル）、ヘキサン−１，６−ジイソシアネート（３モル）、２−ヒドロキシエチルメタクリレート（３モル）の反応生成物Ｍ−２：トリエタノールアミン（１モル）、イソホロンジイソシアネート（３モル）、２−ヒドロキシエチルアクリレート（３モル）の反応生成物
Ｍ−３：Ｎ−ｎ−ブチルジエタノ−ルアミン（１モル）、１，３−ビス（１−イソシアナート−１−メチルエチル）ベンゼン（２モル）、２−ヒドロキシプロピレン−１−メタクリレート−３−アクリレート（２モル）の反応生成物
Ｍ−４：Ｎ−ｎ−ブチルジエタノ−ルアミン（１モル）、１，３−ジ（イソシアナートメチル）ベンゼン（２モル）、２−ヒドロキシプロピレン−１−メタクリレート−３−アクリレート（２モル）の反応生成物
Ｍ−５：Ｎ−メチルジエタノールアミン（１モル）、トリレン−２，４−ジイソシアネート（２モル）、２−ヒドロキシプロピレン−１，３−ジメタクリレート（２モル）の反応生成物
この他にも、特開平１−１０５２３８号公報、特開平２−１２７４０４号公報記載のアクリレートまたはアルキルアクリレートが用いることが出来る。
【００４６】
〈光重合開始剤〉
本発明においては、好ましい光重合開始剤として下記一般式（１）又は（２）で表される構造の臭素化合物、チタノセン化合物、モノアルキルトリアリールボレート化合物及び鉄アレーン錯体化合物等が挙げられる。
【００４７】
一般式（１） Ｒ_１−ＣＢｒ_２−（Ｃ＝Ｏ）−Ｒ_２
式中、Ｒ_１は、水素原子、臭素原子、アルキル基、アリール基、アシル基、アルキルスルホニル基、アリールスルホニル基、シアノ基を表す。Ｒ_２は、一価の置換基を表す。Ｒ_１とＲ_２が結合して環を形成してもかまわない。
【００４８】
一般式（２） ＣＢｒ_３−（Ｃ＝Ｏ）−Ｘ−Ｒ_３
Ｒ_３は、一価の置換基を表す。Ｘは、−Ｏ−、−ＮＲ_４−を表す。Ｒ_４は、水素原子、アルキル基を表す。Ｒ_３とＲ_４が結合して環を形成してもかまわない。
【００４９】
チタノセン化合物としては、特開昭６３−４１４８３号公報、特開平２−２９１号公報に記載される化合物等が挙げられる。好ましい具体例としては、ビス（シクロペンタジエニル）−Ｔｉ−ジ−クロライド、ビス（シクロペンタジエニル）−Ｔｉ−ビス−フェニル、ビス（シクロペンタジエニル）−Ｔｉ−ビス−２，３，４，５，６−ペンタフルオロフェニル、ビス（シクロペンタジエニル）−Ｔｉ−ビス−２，３，５，６−テトラフルオロフェニル、ビス（シクロペンタジエニル）−Ｔｉ−ビス−２，４，６−トリフルオロフェニル、ビス（シクロペンタジエニル）−Ｔｉ−ビス−２，６−ジフルオロフェニル、ビス（シクロペンタジエニル）−Ｔｉ−ビス−２，４−ジフルオロフェニル、ビス（メチルシクロペンタジエニル）−Ｔｉ−ビス−２，３，４，５，６−ペンタフルオロフェニル、ビス（メチルシクロペンタジエニル）−Ｔｉ−ビス−２，３，５，６−テトラフルオロフェニル、ビス（メチルシクロペンタジエニル）−Ｔｉ−ビス−２，６−ジフルオロフェニル（ＩＲＵＧＡＣＵＲＥ７２７Ｌ：チバスペシャリティーケミカルズ社製）、ビス（シクロペンタジエニル）−ビス（２，６−ジフルオロ−３−（ピリ−１−イル）フェニル）チタニウム（ＩＲＵＧＡＣＵＲＥ７８４：チバスペシャリティーケミカルズ社製）、ビス（シクロペンタジエニル）−ビス（２，４，６−トリフルオロ−３−（ピリ−１−イル）フェニル）チタニウムビス（シクロペンタジエニル）−ビス（２，４，６−トリフルオロ−３−（２−５−ジメチルピリ−１−イル）フェニル）チタニウム等が挙げられる。
【００５０】
モノアルキルトリアリールボレート化合物としては、特開昭６２−１５０２４２号公報、特開昭６２−１４３０４４号公報に記載される化合物等挙げられる。好ましい具体例としては、テトラ−ｎ−ブチルアンモニウム ｎ−ブチルートリナフタレン−１−イル−ボレート、テトラ−ｎ−ブチルアンモニウム ｎ−ブチルートリフェニル−ボレート、テトラ−ｎ−ブチルアンモニウム ｎ−ブチルートリ−（４−ｔｅｒｔ−ブチルフェニル）−ボレート、テトラ−ｎ−ブチルアンモニウム ｎ−ヘキシルートリ−（３−クロロ−４−メチルフェニル）−ボレート、テトラ−ｎ−ブチルアンモニウム ｎ−ヘキシルートリ−（３−フルオロフェニル）−ボレート等が挙げられる。
【００５１】
鉄アレーン錯体化合物としては、特開昭５９−２１９３０７号公報に記載される化合物等挙げられる。好ましい具体例としては、η−ベンゼン−（η−シクロペンタジエニル）鉄 ヘキサフルオロホスフェート、η−クメン−（η−シクロペンタジエニル）鉄 ヘキサフルオロホスフェート、η−フルオレン−（η−シクロペンタジエニル）鉄 ヘキサフルオロホスフェート、η−ナフタレン−（η−シクロペンタジエニル）鉄 ヘキサフルオロホスフェート、η−キシレン−（η−シクロペンタジエニル）鉄 ヘキサフルオロホスフェート、η−ベンゼン−（η−シクロペンタジエニル）鉄 テトラフルオロボレート等が挙げられる。
【００５２】
その他に任意の光重合開始剤の併用が可能である。例えばＪ．コーサー（Ｊ．Ｋｏｓａｒ）著「ライト・センシテイブ・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号明細書に開示されている。
【００５３】
即ち、併用が可能な光重合開始剤としては、次のようなものを使用することができる。
【００５４】
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号公報、同６１−９６２１号公報ならびに特開昭６０−６０１０４号記載のトリアジン誘導体；特開昭５９−１５０４号、同６１−２４３８０７号公報記載の有機過酸化物；特公昭４３−２３６８４号公報、同４４−６４１３号公報、同４４−６４１３号公報、同４７−１６０４号公報ならびに米国特許３，５６７，４５３号明細書記載のジアゾニウム化合物；米国特許２，８４８，３２８号明細書、同２，８５２，３７９号明細書ならびに同２，９４０，８５３号明細書記載の有機アジド化合物；特公昭３６−２２０６２号公報、同３７−１３１０９号公報、同３８−１８０１５号公報ならびに同４５−９６１０号公報記載のｏ−キノンジアジド類；特公昭５５−３９１６２号公報、特開昭５９−１４０２３号公報ならびに「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号公報記載のアゾ化合物；特開平１−５４４４０号公報、ヨーロッパ特許１０９，８５１号明細書、同１２６，７１２号明細書ならびに「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号公報及び同５−２５５３４７号公報記載の（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）ならびに特開平２−１８２７０１号公報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号公報記載の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号公報記載の有機ハロゲン化合物等。
【００５５】
光源にレーザー光を用いる場合、好ましくは感光層に増感色素を添加する。光源の波長付近に吸収極大波長を有する色素を用いることが好ましい。
【００５６】
可視光から近赤外まで波長増感させる化合物としては、例えばシアニン、フタロシアニン、メロシアニン、ポルフィリン、スピロ化合物、フェロセン、フルオレン、フルギド、イミダゾール、ペリレン、フェナジン、フェノチアジン、ポリエン、アゾ化合物、ジフェニルメタン、トリフェニルメタン、ポリメチンアクリジン、クマリン、クマリン誘導体、ケトクマリン、キナクリドン、インジゴ、スチリル、ピリリウム化合物、ピロメテン化合物、ピラゾロトリアゾール化合物、ベンゾチアゾール化合物、バルビツール酸誘導体、チオバルビツール酸誘導体等、ケトアルコールボレート錯体が挙げられ、更に欧州特許５６８，９９３号明細書、米国特許４，５０８，８１１号明細書、同５，２２７，２２７号明細書、特開２００１−１２５２５５号公報、特開平１１−２７１９６９号公報等に記載の化合物も用いられる。
【００５７】
上記の光重合開始剤と増感色素の組合せの具体例としては、特開２００１−１２５２５５号公報、特開平１１−２７１９６９号公報に記載のある組合せが挙げられる。
【００５８】
これら重合開始剤の配合量は特に限定されないが、好ましくは、付加重合可能なエチレン性不飽和結合を有する化合物１００質量部に対して０．１〜２０質量部である。光重合開始剤と増感色素の配合比率は、モル比で１：１００〜１００：１の範囲が好ましい。
【００５９】
〈高分子結合材〉
高分子結合材としては、アクリル系重合体、ポリビニルブチラール樹脂、ポリウレタン樹脂、ポリアミド樹脂、ポリエステル樹脂、エポキシ樹脂、フェノール樹脂、ポリカーボネート樹脂、ポリビニルブチラール樹脂、ポリビニルホルマール樹脂、シェラック、その他の天然樹脂等が使用出来る。また、これらを２種以上併用してもよい。
【００６０】
好ましくはアクリル系のモノマーの共重合によって得られるビニル系共重合である。高分子結合材の共重合組成として、（ａ）カルボキシル基含有モノマー、（ｂ）メタクリル酸アルキルエステル、またはアクリル酸アルキルエステルの共重合体であることが好ましい。
【００６１】
カルボキシル基含有モノマーの具体例としては、α，β−不飽和カルボン酸類、例えばアクリル酸、メタクリル酸、マレイン酸、無水マレイン酸、イタコン酸、無水イタコン酸等が挙げられる。その他、フタル酸と２−ヒドロキシメタクリレートのハーフエステル等のカルボン酸も好ましい。メタクリル酸アルキルエステル、アクリル酸アルキルエステルの具体例としては、メタクリル酸メチル、メタクリル酸エチル、メタクリル酸プロピル、メタクリル酸ブチル、メタクリル酸アミル、メタクリル酸ヘキシル、メタクリル酸ヘプチル、メタクリル酸オクチル、メタクリル酸ノニル、メタクリル酸デシル、メタクリル酸ウンデシル、メタクリル酸ドデシル、アクリル酸メチル、アクリル酸エチル、アクリル酸プロピル、アクリル酸ブチル、アクリル酸アミル、アクリル酸ヘキシル、アクリル酸ヘプチル、アクリル酸オクチル、アクリル酸ノニル、アクリル酸デシル、アクリル酸ウンデシル、アクリル酸ドデシル等の無置換アルキルエステルの他、メタクリル酸シクロヘキシル、アクリル酸シクロヘキシル等の環状アルキルエステルや、メタクリル酸ベンジル、メタクリル酸−２−クロロエチル、Ｎ，Ｎ−ジメチルアミノエチルメタクリレート、グリシジルメタクリレート、アクリル酸ベンジル、アクリル酸−２−クロロエチル、Ｎ，Ｎ−ジメチルアミノエチルアクリレート、グリシジルアクリレート等の置換アルキルエステルも挙げられる。
【００６２】
さらに、本発明の高分子結合材は、他の共重合モノマーとして、下記１）〜１４）に記載のモノマー等を用いる事が出来る。
【００６３】
１）芳香族水酸基を有するモノマー、例えばｏ−（又はｐ−，ｍ−）ヒドロキシスチレン、ｏ−（又はｐ−，ｍ−）ヒドロキシフェニルアクリレート等。
【００６４】
２）脂肪族水酸基を有するモノマー、例えば２−ヒドロキシエチルアクリレート、２−ヒドロキシエチルメタクリレート、Ｎ−メチロールアクリルアミド、Ｎ−メチロールメタクリルアミド、４−ヒドロキシブチルメタクリレート、５−ヒドロキシペンチルアクリレート、５−ヒドロキシペンチルメタクリレート、６−ヒドロキシヘキシルアクリレート、６−ヒドロキシヘキシルメタクリレート、Ｎ−（２−ヒドロキシエチル）アクリルアミド、Ｎ−（２−ヒドロキシエチル）メタクリルアミド、ヒドロキシエチルビニルエーテル等。
【００６５】
３）アミノスルホニル基を有するモノマー、例えばｍ−（又はｐ−）アミノスルホニルフェニルメタクリレート、ｍ−（又はｐ−）アミノスルホニルフェニルアクリレート、Ｎ−（ｐ−アミノスルホニルフェニル）メタクリルアミド、Ｎ−（ｐ−アミノスルホニルフェニル）アクリルアミド等。
【００６６】
４）スルホンアミド基を有するモノマー、例えばＮ−（ｐ−トルエンスルホニル）アクリルアミド、Ｎ−（ｐ−トルエンスルホニル）メタクリルアミド等。
【００６７】
５）アクリルアミド又はメタクリルアミド類、例えばアクリルアミド、メタクリルアミド、Ｎ−エチルアクリルアミド、Ｎ−ヘキシルアクリルアミド、Ｎ−シクロヘキシルアクリルアミド、Ｎ−フェニルアクリルアミド、Ｎ−（４−ニトロフェニル）アクリルアミド、Ｎ−エチル−Ｎ−フェニルアクリルアミド、Ｎ−（４−ヒドロキシフェニル）アクリルアミド、Ｎ−（４−ヒドロキシフェニル）メタクリルアミド等。
【００６８】
６）弗化アルキル基を含有するモノマー、例えばトリフルオロエチルアクリレート、トリフルオロエチルメタクリレート、テトラフルオロプロピルメタクリレート、ヘキサフルオロプロピルメタクリレート、オクタフルオロペンチルアクリレート、オクタフルオロペンチルメタクリレート、ヘプタデカフルオロデシルメタクリレート、Ｎ−ブチル−Ｎ−（２−アクリロキシエチル）ヘプタデカフルオロオクチルスルホンアミド等。
【００６９】
７）ビニルエーテル類、例えば、エチルビニルエーテル、２−クロロエチルビニルエーテル、プロピルビニルエーテル、ブチルビニルエーテル、オクチルビニルエーテル、フェニルビニルエーテル等。
【００７０】
８）ビニルエステル類、例えばビニルアセテート、ビニルクロロアセテート、ビニルブチレート、安息香酸ビニル等。
【００７１】
９）スチレン類、例えばスチレン、メチルスチレン、クロロメチルスチレン等。
【００７２】
１０）ビニルケトン類、例えばメチルビニルケトン、エチルビニルケトン、プロピルビニルケトン、フェニルビニルケトン等。
【００７３】
１１）オレフィン類、例えばエチレン、プロピレン、ｉ−ブチレン、ブタジエン、イソプレン等。
【００７４】
１２）Ｎ−ビニルピロリドン、Ｎ−ビニルカルバゾール、４−ビニルピリジン等。
【００７５】
１３）シアノ基を有するモノマー、例えばアクリロニトリル、メタクリロニトリル、２−ペンテンニトリル、２−メチル−３−ブテンニトリル、２−シアノエチルアクリレート、ｏ−（又はｍ−，ｐ−）シアノスチレン等。
【００７６】
１４）アミノ基を有するモノマー、例えばＮ，Ｎ−ジエチルアミノエチルメタクリレート、Ｎ，Ｎ−ジメチルアミノエチルアクリレート、Ｎ，Ｎ−ジメチルアミノエチルメタクリレート、ポリブタジエンウレタンアクリレート、Ｎ，Ｎ−ジメチルアミノプロピルアクリルアミド、Ｎ，Ｎ−ジメチルアクリルアミド、アクリロイルモルホリン、Ｎ−ｉ−プロピルアクリルアミド、Ｎ，Ｎ−ジエチルアクリルアミド等。
【００７７】
これらのモノマーと共重合し得る他のモノマーを共重合してもよい。さらに、上記ビニル系共重合体の分子内に存在するカルボキシル基に、分子内に（メタ）アクリロイル基とエポキシ基を有する化合物を付加反応させる事によって得られる、不飽和結合含有ビニル系共重合体も高分子結合材として好ましい。分子内に不飽和結合とエポキシ基を共に含有する化合物としては、具体的にはグリシジルアクリレート、グリシジルメタクリレート、特開平１１−２７１９６９号公報に記載のあるエポキシ基含有不飽和化合物等が挙げられる。
【００７８】
これらの共重合体は、ゲルパーミエーションクロマトグラフィー（ＧＰＣ）によって測定された重量平均分子量が１〜２０万であるものが好ましいが、この範囲に限定されるものではない。
【００７９】
光重合型感光層における高分子結合材の含有量は、１０〜９０質量％の範囲が好ましく、１５〜７０質量％の範囲が更に好ましく、２０〜５０質量％の範囲で使用することが感度の面から特に好ましい。
【００８０】
高分子結合材の酸価については１０〜１５０の範囲で使用するのが好ましく、３０〜１２０の範囲がより好ましく、５０〜９０の範囲で使用することが、光重合型感光層全体の極性のバランスをとる観点から特に好ましい。これにより光重合型感光層塗布液に顔料を含有させる場合、顔料の凝集を防ぐことができる。
【００８１】
〈支持体〉
支持体としては、感光性平版印刷版賭して用いることのできる任意の支持体を用いることができるが、本発明においてはアルミニウム板が好ましい。
【００８２】
アルミニウム支持体は、純アルミニウムを用いたアルミニウム板材料又はアルミニウム合金を用いたアルミニウム支持体材料から得られる。アルミニウム合金を用いたアルミニウム板材料には、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との合金が用いられ、アルミニウム板の表面は大きなうねりに小ピットが重畳された二重構造の粗面形状を有している。
【００８３】
アルミニウム板は、通常その表面に存在する圧延・巻取り時に使用されたオイルを除去するためにアルカリ、酸、溶剤等で脱脂した後に使用される。脱脂処理としては特にアルカリ水溶液による脱脂が好ましい。また、塗布層との接着性を向上させるために、塗布面に易接着処理や下塗り層塗布を行うことが好ましい。例えば、シランカップリング剤等のカップリング剤を含有する液に浸漬するか、液を塗布した後、十分な乾燥を行う方法が挙げられる。陽極酸化処理も易接着処理の一種と考えられ、使用することができる。また、陽極酸化処理と上記浸漬または塗布処理を組合わせて使用することもできる。また、公知の方法で粗面化されたアルミニウム板を使用することもできる。
【００８４】
〈感光性平版印刷版としてのその他の構成〉
本発明に係る感光性平版印刷版は酸素遮断層を設けることができる。酸素遮断層としては、酸素透過性の低い被膜を形成しうる水溶性ポリマーを使用する。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含有する。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、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。
【００８５】
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出来る。
【００８６】
本発明に係る感光性平版印刷版はオーバーコート層を設けることができる。光重合型感光層とオーバーコート層間の剥離力が３５ｇ／１０ｍｍ以上であることが好ましく、より好ましくは５０ｇ／１０ｍｍ以上、更に好ましくは７５ｇ／１０ｍｍ以上である。剥離力は、オーバーコート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、それを感光性平版印刷版の平面に対して９０度の角度でオーバーコート層と共に剥離する時の力を測定する。
【００８７】
好ましいオーバーコート層の組成としては特開平１０−１０７４２号公報に記載されるものが挙げられる。オーバーコート層には、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。上記オーバーコート層組成物を適当な溶剤に溶解し感光層上に塗布・乾燥してオーバーコート層を形成する。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。オーバーコート層の厚みは０．１〜５．０μｍが好ましく、特に好ましくは０．５〜３．０μｍである。
【００８８】
本発明に係る現像液は、実質的に珪酸塩を含有しない水系アルカリ現像液である。本発明においては、好ましくは本発明に係る現像液はポリオキシアルキレン基を有する界面活性剤を含むことが好ましい。
【００８９】
以下に、本発明に係る現像液について説明する。
〈アルカリ剤〉
本発明に係る現像液は珪酸塩を全く含まないことが好ましい。珪酸塩を含んだとしても、現像液に含まれる珪酸塩の濃度が、ＳｉＯ_２質量換算で０．３％を超えない濃度である。
【００９０】
本発明における現像液および補充液の主成分は、燐酸、炭酸、硼酸、フェノール類、糖類、オキシム類およびフッ素化アルコール類から選ばれる少なくとも一種の化合物、又はそのアルカリ金属塩又は有機カチオンの塩を含有することが好ましい。これらの化合物は、水酸化ナトリウム、水酸化カリウム、水酸化リチウム等のアルカリ金属水酸化物と共存させることで、ｐＨは８．５より高く１３．０未満の範囲のアルカリ性水溶液にして使用することが好ましい。さらに好ましくはｐＨ８．５〜１２である。
【００９１】
これらのうちフェノール類、糖類、オキシム類およびフッ素化アルコール類の如き弱酸性物質としては、解離指数（ｐＫａ）が１０．０〜１３．２のものが好ましい。このような酸としては、ＰｅｒｇａｍｏｎＰｒｅｓｓ社発行のＩＯＮＩＳＡＴＩＯＮ ＣＯＮＳＴＡＮＴＳ ＯＦ ＯＲＧＡＮＩＣ ＡＣＩＤＳ ＩＮＡＱＵＥＯＵＳ ＳＯＬＵＴＩＯＮなどに記載されているものから選ばれ、具体的には、サリチル酸（ｐＫａ１３．０）、３−ヒドロキシ−２−ナフトエ酸（同１２．８４）、カテコール（同１２．６）、没食子酸（同１２．４）、スルホサリチル酸（同１１．７）、３，４−ジヒドロキシスルホン酸（同１２．２）、３，４−ジヒドロキシ安息香酸（同１１．９４）、１，２，４−トリヒドロキシベンゼン（同１１．８２）、ハイドロキノン（同１１．５６）、ピロガロール（同１１．３４）、ｏ−クレゾール（同１０．３３）、レゾルソノール（同１１．２７）、ｐ−クレゾール（同１０．２７）、ｍ−クレゾール（同１０．０９）などのフェノール性水酸基を有するフェノール類が挙げられる。
【００９２】
糖類としてはアルカリ中でも安定な非還元糖が好ましく用いられる。かかる非還元糖とは、遊離のアルデヒド基やケトン基を持たず、還元性を示さない糖類であり、還元基同士の結合したトレハロース型少糖類、糖類の還元基と非糖類が結合した配糖体および糖類に水素添加して還元した糖アルコールに分類され、何れも本発明に好適に用いられる。トレハロース型少糖類には、サッカロースやトレハロースがあり、配糖体としては、アルキル配糖体、フェノール配糖体、カラシ油配糖体などが挙げられる。また糖アルコールとしてはＤ，Ｌ−アラビット、リビット、キシリット、Ｄ，Ｌ−ソルビット、Ｄ，Ｌ−マンニット、Ｄ，Ｌ−イジット、Ｄ，Ｌ−タリット、ズリシットおよびアロズルシットなどが挙げられる。更に二糖類の水素添加で得られるマルチトールおよびオリゴ糖の水素添加で得られる還元体（還元水あめ）が好適に用いられる。更には、２−ブタノンオキシム（ｐＫａ１２．４５）、アセトキシム（同１２．４２）、１．２−シクロヘプタンジオンオキシム（同１２．３）、２−ヒドロキシベンズアルデヒドオキシム（同１２．１０）、ジメチルグリオキシム（同１１．９）、エタンジアミドジオキシム（同１１．３７）、アセトフェノンオキシム（同１１．３５）などのオキシム類、例えば２，２，３，３−テトラフルオロプロパノール−１（同１２．７４）、トリフルオロエタノール（同１２．３７）、トリクロロエタノール（同１２．２４）などのフッ素化アルコール類が挙げられる。他にも、ピリジン−２−アルデヒド（同１２．６８）、ピリジン−４−アルデヒド（同１２．０５）などのアルデヒド類、アデノシン（同１２．５６）、イノシン（同１２．５）、グアニン（同１２．３）、シトシン（同１２．２）、ヒポキサンチン（同１２．１）、キサンチン（同１１．９）などの核酸関連物質、他に、ジエチルアミノメチルスルホン酸（同１２．３２）、１−アミノ−３，３，３−トリフルオロ安息香酸（同１２．２９）、イソプロピリデンジスルホン酸（同１２．１０）、１，１−エチリデンジホスホン酸（同１１．５４）、１，１−エチリデンジスルホン酸１−ヒドロキシ（同１１．５２）、ベンズイミダゾール（同１２．８６）、チオベンズアミド（同１２．８）、ピコリンチオアミド（同１２．５５）、バルビツル酸（同１２．５）などの弱酸が挙げられる。これらの酸性物質は単独でも、また二種以上を組み合わせて用いてもよい。
【００９３】
これらの酸性物質の中で好ましいのは、燐酸、炭酸、スルホサリチル酸、サリチル酸及び非還元糖の糖アルコールとサッカロースであり、特にＤ−ソルビット、サッカロース、還元水あめが適度なｐＨ領域に緩衝作用があることと、低価格であることで好ましい。
【００９４】
これらの酸性物質の現像液中に占める割合は０．１〜３０質量％が好ましく、更に好ましくは、１〜２０質量％である。この範囲以下では十分な緩衝作用が得られず、またこの範囲以上の濃度では、高濃縮化し難く、また原価アップの問題が出てくる。これらの酸に組み合わせる塩基としては、水酸化ナトリウム、同アンモニウム、同カリウムおよび同リチウムが好適に用いられる。これらのアルカリ剤は単独もしくは二種以上を組み合わせて用いられる。現像液のｐＨが８．５以下の場合、このような現像液で現像可能な感光性平版印刷版から得られる印刷版の画像部は物理的に脆弱であり、印刷中の摩耗が早く十分な耐刷力が得られない。また、その画像部は化学的にも弱く、印刷中にインキ洗浄溶剤やプレートクリーナー等で拭いた部分の画像がダメージを受け、その結果、十分な耐薬品性が得られない。ｐＨが１３．０を越える様な高ｐＨの現像液は皮膚や粘膜へ付着した場合の刺激性が強く、取扱いには十分な注意を必要とし好ましくない。
【００９５】
その他として、例えば、燐酸三カリウム、燐酸三ナトリウム、燐酸三リチウム、燐酸三アンモニウム、燐酸二カリウム、燐酸二ナトリウム、燐酸二リチウム、燐酸二アンモニウム、炭酸カリウム、炭酸ナトリウム、炭酸リチウム、炭酸アンモニウム、炭酸水素カリウム、炭酸水素ナトリウム、炭酸水素リチウム、炭酸水素アンモニウム、硼酸カリウム、硼酸ナトリウム、硼酸リチウム、硼酸アンモニウム等があげられ、予め形成された塩の形で加えられてもよい。この場合も、水酸化ナトリウム、同アンモニウム、同カリウムおよび同リチウムをｐＨ調整に加えることができる。また、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、トリ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、エチレンイミン、エチレンジアミン、ピリジンなどの有機アルカリ剤も組み合わせて用いられる。
【００９６】
なお、本発明で言う現像液とは現像のスタート時に使用される未使用の液だけでなく、感光性平版印刷版の処理によって低下する現像液の活性度を補正するために補充液が補充され、活性度が保たれた液（いわゆるランニング液）を含む。補充液は従って、現像液より活性度（アルカリ濃度）が高い必要があるので補充液のｐＨは１３．０を超えていてもよい。
【００９７】
〈界面活性剤〉
本発明に係る現像液には、ポリオキシアルキレン基を有する界面活性剤を含むことが好ましい。この界面活性剤添加により、未露光部の感光層の溶解促進、露光部への現像液の浸透性の低減が可能となる。ポリオキシアルキレン基を有する界面活性剤としては、疎水基全体に占める飽和アルキル部分の割合が分子量で０〜２５％である非イオン界面活性剤（界面活性剤Ａ）、又は疎水基全体に占める飽和アルキル部分の割合が分子量で０〜２５％であるアニオン界面活性剤（界面活性剤Ｂ）、であることが好ましい。
【００９８】
（界面活性剤Ａ）
界面活性剤Ａは、疎水基全体に占める飽和アルキル部分の割合が分子量で０〜２５％（すなわち、疎水基中の飽和アルキル部の比が０〜２５％）であるポリオキシアルキレン基を有する非イオン性界面活性剤を指し、該疎水基全体の分子量の０〜５％であるものが好ましい。
【００９９】
ここで、「疎水基全体に占める飽和アルキル部分の割合が分子量で０〜２５％」とは、分子中に飽和アルキル部分を有する疎水基を、２以上有する場合には、その分子が有する全ての疎水基の元素について合計した分子量を分母として、また、その全ての疎水基が有する飽和アルキル部分の元素についての分子量を分子（飽和アルキル部）として計算した結果を％表示したものである。この場合において、幾つかの疎水基を分子が有する場合に、各疎水基が平均して「疎水基全体に占める飽和アルキル部分の割合が分子量で０〜２５％である」ことが好ましいが、各疎水基が平均して上記の範囲にないものも有用である。
【０１００】
また、疎水基の元素についての合計した分子量は、ある程度の大きさを有することが好ましく、分子量が１２０以上２０００以下程度のものが好ましい。
【０１０１】
次に、界面活性剤Ａの好ましい例を挙げるが、本発明においては、これらに限定されるものではない。なお、（）内の％は上記の疎水基全体に占める飽和アルキル部分の割合を表す。
【０１０２】
【化２】

【０１０３】
【化３】

【０１０４】
界面活性剤Ａは、現像液中に０．１〜１０質量％含有されることが好ましく、更に、０．５〜５．０質量％含有されることが好ましい。
【０１０５】
（界面活性剤Ｂ）
界面活性剤Ｂは、疎水基全体に占める飽和アルキル部分の割合が分子量で０〜２５％（すなわち、疎水基中の飽和アルキル部の比が０〜２５％）であるポリオキシアルキレン基を有するアニオン性界面活性剤を指し、該疎水基全体の分子量の０〜５％であるものが好ましい。
【０１０６】
ここで、「疎水基全体に占める飽和アルキル部分の割合が分子量で０〜２５％」とは、界面活性剤Ａと同義である。
【０１０７】
次に、界面活性剤Ｂの好ましい例を挙げるが、本発明においては、これらに限定されるものではない。なお、（）内の％は上記の疎水基全体に占める飽和アルキル部分の割合を表す。
【０１０８】
【化４】

【０１０９】
【化５】

【０１１０】
界面活性剤Ｂは、現像液中に０．１〜１０質量％含有されることが好ましく、更に、０．５〜５．０質量％含有されることが好ましい。
【０１１１】
また、上記した界面活性剤Ａおよび界面活性剤Ｂにおいて、疎水基の分子量が小さすぎると感光性平版印刷版の光重合型感光層の現像時での溶解能力が低下し、スラッジ、ヘドロの発生が抑制しにくくなり、一方、疎水基の分子量が大きすぎると、これら化合物の現像液への溶解性が悪くなり均一な現像液を作製・維持し難くなることから上記した範囲が好ましい。
【０１１２】
本発明に係る現像液は、必要に応じて公知の添加剤を含有することができる。
（界面活性剤）
本発明に用いられる現像液および補充液には、現像性の促進や現像カスの分散および印刷版画像部の親インキ性を高める目的で必要に応じて種々界面活性剤や有機溶剤を添加できる。好ましい界面活性剤としては、アニオン系、カチオン系、ノニオン系および両性界面活性剤が挙げられる。
【０１１３】
界面活性剤の好ましい例としては、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アルキルフェニルエーテル類、ポリオキシエチレンポリスチリルフェニルエーテル類、ポリオキシエチレンポリオキシプロピレンアルキルエーテル類、グリセリン脂肪酸部分エステル類、ソルビタン脂肪酸部分エステル類、ペンタエリスリトール脂肪酸部分エステル類、プロピレングリコールモノ脂肪酸エステル類、しょ糖脂肪酸部分エステル類、ポリオキシエチレンソルビタン脂肪酸部分エステル類、ポリオキシエチレンソルビトール脂肪酸部分エステル類、ポリエチレングリコール脂肪酸エステル類、ポリグリセリン脂肪酸部分エステル類、ポリオキシエチレン化ひまし油類、ポリオキシエチレングリセリン脂肪酸部分エステル類、ポリオキシエチレン−ポリオキシプロピレンブロック共重合体、エチレンジアミンのポリオキシエチレン−ポリオキシプロピレンブロック共重合体付加物、脂肪酸ジエタノールアミド類、Ｎ，Ｎ−ビス−２−ヒドロキシアルキルアミン類、ポリオキシエチレンアルキルアミン、トリエタノールアミン脂肪酸エステル、トリアルキルアミンオキシドなどの非イオン性界面活性剤、脂肪酸塩類、アビエチン酸塩類、ヒドロキシアルカンスルホン酸塩類、アルカンスルホン酸塩類、ジアルキルスルホ琥珀酸エステル塩類、直鎖アルキルベンゼンスルホン酸塩類、分岐鎖アルキルベンゼンスルホン酸塩類、アルキルナフタレンスルホン酸塩類、アルキルジフェニルエーテルスルホン酸塩類、アルキルフェノキシポリオキシエチレンプロピルスルホン酸塩類、ポリオキシエチレンアルキルスルホフェニルエーテル塩類、Ｎ−メチル−Ｎ−オレイルタウリンナトリウム塩、Ｎ−アルキルスルホ琥珀酸モノアミド二ナトリウム塩、石油スルホン酸塩類、硫酸化牛脂油、脂肪酸アルキルエステルの硫酸エステル塩類、アルキル硫酸エステル塩類、ポリオキシエチレンアルキルエーテル硫酸エステル塩類、脂肪酸モノグリセリド硫酸エステル塩類、ポリオキシエチレンアルキルフェニルエーテル硫酸エステル塩類、ポリオキシエチレンスチリルフェニルエーテル硫酸エステル塩類、アルキルリン酸エステル塩類、ポリオキシエチレンアルキルエーテルリン酸エステル塩類、ポリオキシエチレンアルキルフェニルエーテルリン酸エステル塩類、スチレン／無水マレイン酸共重合物の部分鹸化物類、オレフィン／無水マレイン酸共重合物の部分鹸化物類、ナフタレンスルホン酸塩ホルマリン縮合物類などのアニオン界面活性剤、アルキルアミン塩類、テトラブチルアンモニウムブロミド等の第四級アンモニウム塩類、ポリオキシエチレンアルキルアミン塩類、ポリエチレンポリアミン誘導体などのカチオン性界面活性剤、カルボキシベタイン類、アミノカルボン酸類、スルホベタイン類、アミノ硫酸エステル類、イミダゾリン類などの両性界面活性剤が挙げられる。以上挙げた界面活性剤の中でポリオキシエチレンとあるものは、ポリオキシメチレン、ポリオキシプロピレン、ポリオキシブチレンなどのポリオキシアルキレンに読み替えることもでき、それらの界面活性剤もまた包含される。更に好ましい界面活性剤は分子内にパーフルオロアルキル基を含有するフッ素系の界面活性剤である。係るフッ素系界面活性剤としては、パーフルオロアルキルカルボン酸塩、パーフルオロアルキルスルホン酸塩、パーフルオロアルキルリン酸エステルなどのアニオン型、パーフルオロアルキルベタインなどの両性型、パーフルオロアルキルトリメチルアンモニウム塩などのカチオン型およびパーフルオロアルキルアミンオキサイド、パーフルオロアルキルエチレンオキシド付加物、パーフルオロアルキル基および親水性基含有オリゴマー、パーフルオロアルキル基および親油性基含有オリゴマー、パーフルオロアルキル基、親水性基および親油性基含有オリゴマー、パーフルオロアルキル基および親油性基含有ウレタンなどの非イオン型が挙げられる。
【０１１４】
上記の界面活性剤は、単独もしくは２種以上を組み合わせて使用することができ、現像液中に０．００１〜１０質量％、より好ましくは０．０１〜５質量％の範囲で添加される。
【０１１５】
（現像安定化剤）
本発明に用いられる現像液および補充液には、好ましくは現像安定化剤が用いられる。それらの好ましい例として、特開平６−２８２０７９号公報記載の糖アルコールのポリエチレングリコール付加物、テトラブチルアンモニウムヒドロキシドなどのテトラアルキルアンモニウム塩、テトラブチルホスホニウムブロマイドなどのホスホニウム塩およびジフェニルヨードニウムクロライドなどのヨードニウム塩が好ましい例として挙げられる。更に、特開昭５０−５１３２４号公報記載のアニオン界面活性剤または両性界面活性剤、また特開昭５５−９５９４６号公報記載の水溶性カチオニックポリマー、特開昭５６−１４２５２８号公報に記載されている水溶性の両性高分子電解質を挙げることができる。更に、特開昭５９−８４２４１号公報のアルキレングリコールが付加された有機硼素化合物、特開昭６０−１１１２４６号公報記載のポリオキシエチレン−ポリオキシプロピレンブロック重合型の水溶性界面活性剤、特開昭６０−１２９７５０号公報のポリオキシエチレン−ポリオキシプロピレンを置換したアルキレンジアミン化合物、特開昭６１−２１５５５４号公報記載の重量平均分子量３００以上のポリエチレングリコール、特開昭６３−１７５８５８号公報のカチオン性基を有する含フッ素界面活性剤、特開平２−３９１５７号公報の酸またはアルコールに４モル以上のエチレンオキシドを付加して得られる水溶性エチレンオキシド付加化合物と、水溶性ポリアルキレン化合物などが挙げられる。
【０１１６】
（有機溶剤）
現像液および現像補充液には更に必要により有機溶剤が加えられる。係る有機溶剤としては、水に対する溶解度が約１０質量％以下のものが適しており、好ましくは５質量％以下のものから選ばれる。例えば、１−フェニルエタノール、２−フェニルエタノール、３−フェニル−１−プロパノール、４−フェニル−１−ブタノール、４−フェニル−２−ブタノール、２−フェニル−１−ブタノール、２−フェノキシエタノール、２−ベンジルオキシエタノール、ｏ−メトキシベンジルアルコール、ｍ−メトキシベンジルアルコール、ｐ−メトキシベンジルアルコール、ベンジルアルコール、シクロヘキサノール、２−メチルシクロヘキサノール、３−メチルシクロヘキサノールおよび４−メチルシクロヘキサノール、Ｎ−フェニルエタノールアミンおよびＮ−フェニルジエタノールアミンなどを挙げることができる。
【０１１７】
有機溶剤の含有量は使用液の総質量に対して０．１〜５質量％であるが、実質的に含まれないことが好ましく、全く含まれないことが特に好ましい。ここで実質的に含まれないとは１質量％以下であることを示す。
【０１１８】
（還元剤）
本発明に用いられる現像液および補充液には必要に応じて還元剤が加えられる。これは印刷版の汚れを防止するものであり、特に感光性ジアゾニウム塩化合物を含むネガ型感光性平版印刷版を現像する際に有効である。好ましい有機還元剤としては、チオサリチル酸、ハイドロキノン、メトール、メトキシキノン、レゾルシン、２−メチルレゾルシンなどのフェノール化合物、フェニレンジアミン、フェニルヒドラジンなどのアミン化合物が挙げられる。
【０１１９】
更に好ましい無機の還元剤としては、亜硫酸、亜硫酸水素酸、亜リン酸、亜リン酸水素酸、亜リン酸二水素酸、チオ硫酸および亜ジチオン酸などの無機酸のナトリウム塩、カリウム塩、アンモニウム塩などを挙げることができる。これらの還元剤のうち汚れ防止効果が特に優れているのは亜硫酸塩である。これらの還元剤は使用時の現像液に対して好ましくは、０．０５〜５質量％の範囲で含有される。
【０１２０】
（有機カルボン酸）
本発明に用いられる現像液および補充液には必要に応じて更に有機カルボン酸を加えることもできる。好ましい有機カルボン酸は炭素原子数６〜２０の脂肪族カルボン酸および芳香族カルボン酸を挙げることができる。
【０１２１】
脂肪族カルボン酸の具体的な例としては、カプロン酸、エナンチル酸、カプリル酸、ラウリン酸、ミリスチン酸、パルミチン酸およびステアリン酸などがあり、特に好ましいのは炭素数８〜１２のアルカン酸である。また炭素鎖中に二重結合を有する不飽和脂肪酸でも、枝分かれした炭素鎖のものでも良い。芳香族カルボン酸としてはベンゼン環、ナフタレン環、アントラセン環などにカルボキシル基が置換された化合物で、具体的には、ｏ−クロロ安息香酸、ｐ−クロロ安息香酸、ｏ−ヒドロキシ安息香酸、ｐ−ヒドロキシ安息香酸、ｏ−アミノ安息香酸、ｐ−アミノ安息香酸、２，４−ジヒドロキシ安息香酸、２，５−ジヒドロキシ安息香酸、２，６−ジヒドロキシ安息香酸、２，３−ジヒドロキシ安息香酸、３，５−ジヒドロキシ安息香酸、没食子酸、１−ヒドロキシ−２−ナフトエ酸、３−ヒドロキシ−２−ナフトエ酸、２−ヒドロキシ−１−ナフトエ酸、１−ナフトエ酸、２−ナフトエ酸などがあるがヒドロキシナフトエ酸は特に有効である。上記脂肪族および芳香族カルボン酸は水溶性を高めるためにナトリウム塩やカリウム塩またはアンモニウム塩として用いるのが好ましい。
【０１２２】
本発明で用いる現像液の有機カルボン酸の含有量は格別な制限はないが、０．１質量％より低いと効果が十分でない場合もあり、また１０質量％以上ではそれ以上の効果の改善が見られない場合もあり、従って、好ましい添加量は使用時の現像液に対して０．１〜１０質量％であり、より好ましくは０．５〜４質量％である。
【０１２３】
（その他添加剤）
本発明に用いられる現像液および補充液には現像性能を高めるために前記の他に以下のような添加剤を加えることができる。例えば特開昭５８−７５１５２号公報記載のＮａＣｌ、ＫＣｌ、ＫＢｒ等の中性塩、特開昭５９−１２１３３６号公報記載の［Ｃｏ（ＮＨ_３）］_６Ｃｌ_３等の錯体、特開昭５６−１４２２５８号公報記載のビニルベンジルトリメチルアンモニウムクロライドとアクリル酸ナトリウムの共重合体等の両性高分子電解質、特開昭５９−７５２５５号公報記載のＳｉ、Ｔｉ等を含む有機金属界面活性剤、特開昭５９−８４２４１号公報記載の有機硼素化合物等が挙げられる。本発明に用いられる現像液および補充液には更に必要に応じて、防腐剤、着色剤、増粘剤、消泡剤および硬水軟化剤などを含有させることもできる。消泡剤としては例えば、特開平２−２４４１４３号公報記載の鉱物油、植物油、アルコール、界面活性剤、シリコーン等が挙げられる。硬水軟化剤としては例えば、ポリ燐酸およびそのナトリウム塩、カリウム塩およびアンモニウム塩、エチレンジアミンテトラ酢酸、ジエチレントリアミンペンタ酢酸、トリエチレンテトラミンヘキサ酢酸、ヒドロキシエチルエチレンジアミントリ酢酸、ニトリロトリ酢酸、１，２−ジアミノシクロヘキサンテトラ酢酸および１，３−ジアミノ−２−プロパノールテトラ酢酸などのアミノポリカルボン酸およびそれらのナトリウム塩、カリウム塩およびアンモニウム塩、アミノトリ（メチレンホスホン酸）、エチレンジアミンテトラ（メチレンホスホン酸）、ジエチレントリアミンペンタ（メチレンホスホン酸）、トリエチレンテトラミンヘキサ（メチレンホスホン酸）、ヒドロキシエチルエチレンジアミントリ（メチレンホスホン酸）および１−ヒドロキシエタン−１，１−ジホスホン酸やそれらのナトリウム塩、カリウム塩およびアンモニウム塩を挙げることができる。
【０１２４】
このような硬水軟化剤はそのキレート化力と使用される硬水の硬度および硬水の量によって最適値が変化するが、一般的な使用量を示せば、使用時の現像液に０．０１〜５質量％、より好ましくは０．０１〜０．５質量％の範囲である。
【０１２５】
（濃縮液）
本発明に用いられる現像液および補充液は使用時よりも水の含有量を少なくした濃縮液としておき、使用時に水で希釈するようにしておくことが運搬上有利である。この場合の濃縮度は各成分が分離や析出を起こさない程度が適当であるが、必要により可溶化剤を加えることが好ましい。かかる可溶化剤としては、特開平６−３２０８１号公報記載のトルエンスルホン酸、キシレンスルホン酸およびそれらのアルカリ金属塩等のいわゆるヒドロトロープ剤が好ましく用いられる。濃縮液の水の含有量をさらに減らし、固形状もしくはペースト状にすることもできる。この場合、一旦現像液にしてから蒸発乾固しても良いが、好ましくは複数の素材を混ぜ合わせる際に水を加えず、または少量の水を加える方法で素材を混ぜ合わせることで濃縮状態とする方法が好ましい。また、この現像液濃縮物は、特開昭５１−６１８３７、特開平２−１０９０４２、特開平２−１０９０４３、特開平３−３９７３５、特開平５−１４２７８６、特開平６−２６６０６２、特開平７−１３３４１等に記載された従来よく知られた方法にて顆粒状、錠剤とすることができる。固形状もしくはペースト状の現像液濃縮物に含まれる素材は、通常の感光性平版印刷版の現像液に用いられる成分を使用することができるが、水で希釈してももとに戻らないものは含まない方が好ましい。たとえば、珪酸塩は水分が低くなると石化し水に溶けにくくなるので、珪酸塩の代わりに炭酸塩、燐酸塩、有機酸塩等を含むことが好ましい。
【０１２６】
これらの現像液の濃縮液もしくは固形状もしくはペースト状の濃縮物は、素材種や素材配合比等の異なる複数のパートに分けても良い。これらの濃縮した現像液濃縮物は、現像前に水で所定の濃度に希釈した後現像に使用することが好ましい。またこの現像液濃縮液または濃縮物を現像補充液として用いる場合は、所定の濃度に水で希釈した後、使用中の現像液に投入することが最も好ましいが、所定の濃度より濃い濃度や、所定の濃度に希釈せずそのまま使用中の現像液に投入することも可能である。所定の濃度より濃い濃度や、所定の濃度に希釈せずそのままで現像液濃縮物を使用中の現像液に投入する際は、同じタイミングまたは別のタイミングで使用中の現像液に直接別途に水を添加しても良い。
【０１２７】
〈露光〉
感光性平版印刷版における光重合型感光層を、例えば、カーボンアーク灯、高圧水銀灯、キセノンランプ、メタルハライドランプ、蛍光ランプ、タングステンランプ、ハロゲンランプ、ヘリウムカドミニウムレーザー、アルゴンイオンレーザー、ＦＤ・ＹＡＧレーザー、ヘリウムネオンレーザー、半導体レーザー（３５０ｎｍ〜６００ｎｍ）等の従来公知の活性光線で画像露光した後、現像処理することにより、支持体表面に画像を形成することができる。画像露光後、現像までの間に、光重合型感光層の硬化率を高める目的で５０℃〜１５０℃の温度で１秒、５分の時間の加熱プロセスを設けることを行っても良い。
【０１２８】
〈自動現像機〉
本発明に用いる自動現像機は、現像液を収納する現像処理漕及び該現像処理漕から排出される現像液廃液を収納する現像処理廃液漕を有することが必須である。本発明においては、現像処理廃液漕は、自動現像機内に設置されていても、自動現像機外近傍に設置されていてもよい。
【０１２９】
この必須の機構に加えて感光性平版印刷版の処理に適用する自動現像機に備わっている任意の機構を持つことができる。例えば、好ましくは現像液漕に自動的に補充液を必要量補充する機構が付与されている。また、好ましくは現像液漕に自動的に水を必要量補充する機構が付与されており、好ましくは、感光性平版印刷版の通過を検知（通版の検知）する機構が付与されており、好ましくは通版の検知をもとに版の処理面積を推定する機構が付与されており、好ましくは通版の検知および／または処理面積の推定をもとに補充しようとする補充液および／または水の補充量および／または補充タイミングを制御する機構が付与されており、好ましくは現像液の温度を制御する機構が付与されており、好ましくは現像液のｐＨおよび／または電導度を検知する機構が付与されており、好ましくは現像液のｐＨおよび／または電導度をもとに補充しようとする補充液および／または水の補充量および／または補充タイミングを制御する機構が付与されている。また、現像工程後に水洗工程がある場合、使用後の水洗水を現像濃縮液、現像補充液の濃縮液の希釈水として用いることができる。
【０１３０】
本発明に用いる自動現像機は、現像工程の前に前処理液に版を浸漬させる前処理部を有してもよい。この前処理部は、好ましくは版面に前処理液をスプレーする機構が付与されており、好ましくは前処理液の温度を２５℃〜５５℃の任意の温度に制御する機構が付与されており、好ましくは版面をローラー状のブラシにより擦る機構が付与されている。またこの前処理液としては、水などが用いられる。
【０１３１】
本発明に用いられる自動現像機は、現像液の水の蒸発分を補うため、水を補充する機能を持つことが好ましい。自動現像機に濃縮現像液を希釈する為の水供給機構があればそれを用いてもよい。水の補充量は時間あたりで決められた水を補充する方法がもっとも簡便で好ましいが、現像液のｐＨ、電動度等のセンサーからの測定値から水補充量を補正してもよい。また、外気の気温および／または湿度、現像液の温度、自動現像機内の空気の温度および／または湿度等を用いての水の補充量に補正をしてもよい。
【０１３２】
〈現像処理〉
本発明の感光性平版印刷版の処理方法の態様としては、基本的には４つ挙げられる。第一は、自動現像機内に存在する空気を現像処理廃液漕に収納された現像液廃液に強制的に接触させながら現像処理すること（請求項１記載の発明）、第二は、現像処理漕内に存在する空気を現像処理廃液漕に収納された現像液廃液に強制的に接触させ、次いで接触した空気を現像処理漕内に循環させながら現像処理すること（請求項２記載の発明）、第三は、現像液廃液を用いて脱炭酸ガス化した空気を現像処理漕内に送り込みながら現像処理すること（請求項３記載の発明）、第四は、現像液廃液を用いて脱炭酸ガス化した空気を自動現像機内に送り込みながら現像処理すること（請求項４記載の発明）である。
【０１３３】
現像処理廃液漕に収納された現像液廃液に強制的に空気を接触させる方法としては、次のような物理的手段により空気を現像液廃液中に導き現像液廃液と接触させる方法がある。
【０１３４】
１）現像処理廃液漕に収納された現像液廃液を自動現像機内に存在する空気と接触させた状態で現像液廃液側を攪拌することにより接触を促進させる。接触を促進することにより効率よく空気中の炭酸ガスを除去することができる。現像液廃液を自動現像機内に存在する空気と接触させた状態で、現像液廃液側をスクリューなどで強く攪拌することで、空気と現像液廃液との接触面積を増大させることが好ましい。この攪拌は空気が現像液廃液に泡状に引き込まれる程度に強く攪拌することでより高い効果が得られる。この方法では送液ポンプが必須でない為、現像液廃液成分がポンプに詰まる等の不具合を回避することができる。
【０１３５】
２）現像処理廃液漕に収納された現像液廃液の中に自動現像機内に存在する空気をバブリングすることにより接触を促進させる。具体的には、エアポンプを用いて自動現像機内に存在する空気を、現像液廃液中にバブリングし、空気と現像液廃液との接触面積を増大させるものである。この場合、エアポンプを使用するものの現像液廃液側には送液ポンプが必須でない為、現像液廃液成分がポンプに詰まる等の不具合を回避することができる。
【０１３６】
３）自動現像機内に存在する空気中で又は現像液を収納する現像処理漕内に存在する空気中で現像処理廃液漕に収納された現像液廃液をスプレイノズル等で霧状に吐出することにより接触を促進させる。この場合、滴下した現像液廃液側の着地点に傾斜を持たせたり、衝撃を吸収する構造を持たせることで、液滴の着地での衝撃をやわらげ、飛沫の飛び散りや発泡による不具合を回避することができる。また、空気が進入する部分に重点的に滴下することで効率のよい炭酸ガス除去を行うことができる。
【０１３７】
上記１）及び２）の方法において、現像液を収納する現像処理漕内に存在する空気を現像処理漕の外で現像液廃液と接触させる場合には、現像液廃液と接触し炭酸ガスを除去した空気を現像処理漕内に戻すことが必要である。この場合、炭酸ガスを除去した空気は、現像液の液面付近に戻すことが好ましい。
【０１３８】
また、本発明は、実質的に珪酸塩を含有しない水系アルカリ現像液が空気中に存在する炭酸ガスにより劣化するのを低減する方法に関するものであり、感光性平版印刷版を処理していないときにでも適用できるものである。
【０１３９】
基本的には４つ挙げられる。第一は、自動現像機内に存在する空気を現像処理廃液漕に収納された現像液廃液に強制的に接触させることにより自動現像機内に存在する空気中の炭酸ガスを減少させること（請求項８記載の発明）、第二は、現像処理漕内に存在する空気を現像処理廃液漕に収納された現像液廃液に強制的に接触させ、次いで接触した空気を現像処理漕内に循環させることにより現像処理漕内に存在する空気中の炭酸ガスを減少させること（請求項９記載の発明）、第三は、現像液廃液を用いて脱炭酸ガス化した空気を前記現像処理漕内に送り込むこと（請求項１０記載の発明）、第四は、現像液廃液を用いて脱炭酸ガス化した空気を自動現像機内に送り込むこと（請求項１１記載の発明）である。
【０１４０】
炭酸ガスは通常大気中に０．０３ｖｏｌ％含まれており、この１／２以下、すなわち０．０１５ｖｏｌ％に低減させることが好ましい。室内の環境では石油ストーブ等の影響で、炭酸ガス濃度が上昇するケースがあり、この場合はより顕著に本発明の効果が現れる。炭酸ガス濃度は、自動現像機のある室内空気に含まれる炭酸ガスの１／２以下の濃度に低減されることが好ましい。
【０１４１】
空気を現像処理廃液漕に収納された現像液廃液に強制的に接触させる方法は、前記した方法を採用することができる。空気を現像処理廃液漕に収納された現像液廃液に強制的に接触させることにより自動現像機内に存在する空気中の炭酸ガスを減少させる時期については、感光性平版印刷版を処理している最中でもよいことはもちろんであるが、感光性平版印刷版を処理していないときでもよい。
【０１４２】
請求項１０及び請求項１１記載の発明では、現像液廃液に強制的に接触させる空気は、自動現像機外近傍の空気であってもよい。
【０１４３】
また、請求項９記載の発明及び請求項１０記載の発明においては、脱炭酸ガス化した空気は現像液の液面付近に送ることが好ましい。
【０１４４】
〈現像後の処理工程〉
このようにして現像処理された感光性平版印刷版は特開昭５４−８００２号、同５５−１１５０４５号、同５９−５８４３１号等の各公報に記載されているように、水洗水、界面活性剤等を含有するリンス液、アラビアガムや澱粉誘導体等を含む不感脂化液で後処理される。本発明の感光性平版印刷版の後処理にはこれらの処理を種々組み合わせて用いることができる。上記の様な処理により得られた印刷版は特開２０００−８９４７８号に記載の方法による後露光処理やバーニングなどの加熱処理により、耐刷性を向上させることができる。このような処理によって得られた平版印刷版はオフセット印刷機に掛けられ、多数枚の印刷に用いられる。
【０１４５】
【実施例】
以下に、合成例、支持体作製例、実施例を具体的に示すが、本発明の実施態様は、これ等に限定されるものでない。尚、実施例における「部」は、特に断りない限り「質量部」を表す。
【０１４６】
（実施例１）
《感光性平版印刷版の作製》
〈感光性平版印刷版１の作製〉
下記支持体上に、下記組成の光重合型感光層塗工液１を乾燥時１．５ｇ／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、光重合型感光層塗布試料を得た。
【０１４７】
（高分子結合材（アクリル系共重合体１）の合成）
窒素気流下の三ツ口フラスコに、メタクリル酸３０部、メタクリル酸メチル５０部、メタクリル酸エチル２０部、イソプロピルアルコール５００部及びα、α′−アゾビスイソブチロニトリル３部を入れ、窒素気流中８０℃のオイルバスで６時間反応させた。その後、イソプロピルアルコールの沸点で１時間還流を行った後、トリエチルアンモニウムクロライド３部及びグリシジルメタクリレート２５部を加えて３時間反応させ、アクリル系共重合体１を得た。ＧＰＣを用いて測定した重量平均分子量は約３５，０００、ＤＳＣ（示差熱分析法）を用いて測定したガラス転移温度（Ｔｇ）は約８５℃であった。
【０１４８】
（支持体の作製）
厚さ０．３ｍｍ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％の硝酸水溶液中で、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１％ポリビニルホスホン酸で７５℃にて、親水化処理を行って支持体を作製した。
【０１４９】
この時、表面の中心線平均粗さ（Ｒａ）は０．６５μｍであった。
（光重合型感光層塗工液１）

【０１５０】
【化６】

【０１５１】
上記光重合型感光層塗布試料上に、下記組成の酸素遮断層塗工液１を乾燥時１．８ｇ／ｍ^２になるようになるようアプリケーターで塗布し、７５℃で１．５分間乾燥して、感光層上に酸素遮断層を有する感光性平版印刷版１を作製した。
【０１５２】
（酸素遮断層塗工液１）
ポリビニルアルコール（ＧＬ−０５：日本合成化学社製） ８９部
水溶性ポリアミド（Ｐ−７０：東レ社製） １０部
界面活性剤（サーフィノール４６５：日信化学工業社製） ０．５部
水 ９００部
〈感光性平版印刷版２の作製〉
光重合型感光層塗工液１において、光重合開始剤をＩ−３（４．０部）、分光増感色素をＤ−３（３．０部）に代えた以外は、感光性平版印刷版１の作製と同様の方法で感光性平版印刷版２を作製した。
【０１５３】
【化７】

【０１５４】
〈感光性平版印刷版３の作製〉
光重合型感光層塗工液１において、分光増感色素をＤ−５（１．５部）、Ｄ−７（１．５部）に代えた以外は、感光性平版印刷版１の作製と同様の方法で感光性平版印刷版３を作製した。
【０１５５】
【化８】

【０１５６】
《現像液処方》

《フィニッシャー液処方》
（版面保護剤（ガム液）１Ｌ 水溶液処方）
白色デキストリン ５．０質量％
ヒドロキシプロピルエーテル化デンプン １０．０質量％
アラビアガム １．０質量％
燐酸第１アンモン ０．１質量％
ジラウリルコハク酸ナトリウム ０．１５質量％
ポリオキシエチレンナフチルエーテル ０．５質量％
ポリオキシエチレンポリオキシプロピレンのブロック共重合体
（エチレンオキシド比５０ｍｏｌ％、分子量５０００） ０．３質量％
エチレングリコール １．０質量％
エチレンジアミンテトラ酢酸２ナトリウム ０．００５質量％
エチルパラベン ０．００５質量％
《露光》
上記のようにして作製した感光性平版印刷版１及び２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２４００ｄｐｉ（ｄｐｉとは２．５４ｃｍあたりのドット数を表す）の解像度で画像露光（露光パターンは、１００％画像部と、１７５ＬＰＩ ５０％のスクエアードットを使用した）を行った。また、感光性平版印刷版３については、４０８ｎｍ、３０ｍＷ出力のレーザーを備えたプレートセッター（タイガーキャット：ＥＣＲＭ社製改造品）を用いて同様の画像露光を行った。
【０１５７】
次いで、下記のＣＴＰ自動現像機で、画像部、非画像部の面積比率が、１：９になるよう現像を５００ｍ^２実施した。約５０ｍｌ／ｍ^２となるように現像液の補充を実施した。
【０１５８】
《現像処理》
〈現像処理１〉（本発明）
現像前に酸素遮断層を除去する前水洗部、現像液を充填した現像部（現像処理漕）、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上記のガム液を備えたＣＴＰ自動現像機（ＰＨＷ３２−Ｖ：Ｔｅｃｈｎｉｇｒａｐｈ社製）を用い、現像廃液によって得られたオーバーフロー液を一時的に蓄える蓋付きの５Ｌの容器（現像処理廃液漕）を設け、初めは使用されていない現像補充液で満たした。現像処理につれて現像ランニング液のオーバーフロー液（現像液廃液）が流れ込むようにし、５Ｌ以上になった部分は廃棄することで、徐々に現像液廃液への変更を進めた。この状態で現像処理漕上の空間に存在する空気をエアポンプにて取り出して、上記の蓋付きの５Ｌの容器（現像処理廃液漕）の中に流しつつ一方で空気を抜き取り、その空気を現像処理漕内に戻した。さらに蓋付きの５Ｌの容器内の現像液廃液をスクリューにて攪拌し、この現像液廃液と空気との接触を促進した。
【０１５９】
〈現像処理２〉（本発明）
現像前に酸素遮断層を除去する前水洗部、現像液を充填した現像部（現像処理漕）、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上記のガム液を備えたＣＴＰ自動現像機（ＰＨＷ３２−Ｖ：Ｔｅｃｈｎｉｇｒａｐｈ社製）を用い、現像廃液によって得られたオーバーフロー液を一時的に蓄える蓋付きの５Ｌの容器（現像処理廃液漕）を設け、初めは使用されていない現像補充液で満たした。現像処理につれて現像ランニング液のオーバーフロー液（現像液廃液）が流れ込むようにし、５Ｌ以上になった部分は廃棄することで、徐々に現像液廃液への変更を進めた。この状態で現像処理漕上の空間に存在する空気をエアポンプにて取り出して、上記の蓋付きの５Ｌの容器（現像処理廃液漕）中の現像廃液中の底の部分からバブリングしつつ、液面から上がった空気を抜き取り、その空気を現像処理漕内に戻すことにより、この現像液廃液と空気との接触を促進した。
【０１６０】
〈現像処理３〉（本発明）
現像前に酸素遮断層を除去する前水洗部、現像液を充填した現像部（現像処理漕）、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上記のガム液を備えたＣＴＰ自動現像機（ＰＨＷ３２−Ｖ：Ｔｅｃｈｎｉｇｒａｐｈ社製）を用い、現像廃液によって得られたオーバーフロー液を一時的に蓄える蓋付きの５Ｌの容器（現像処理廃液漕）を設け、初めは使用されていない現像補充液で満たした。現像処理につれて現像ランニング液のオーバーフロー液（現像液廃液）が流れ込むようにし、５Ｌ以上になった部分は廃棄することで、徐々に現像液廃液への変更を進めた。この液を送液ポンプにて自動現像機の現像処理漕と現像部蓋の間の空気に接触するよう、シャワー状に繰り返し滴下し、滴下し終わった液は再び蓋付きの５Ｌの容器（現像処理廃液漕）に戻るようにすることにより、この現像液廃液と空気との接触を促進した。
【０１６１】
〈現像処理４〉（比較例）
現像前に酸素遮断層を除去する前水洗部、現像液を充填した現像部、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上記のガム液を備えたＣＴＰ自動現像機（ＰＨＷ３２−Ｖ：Ｔｅｃｈｎｉｇｒａｐｈ社製）を現像処理廃液漕を設けずに、通常の現像処理をした。
【０１６２】
《評価》
〈非画像部のインキ汚れ〉
上記各感光性平版印刷版を、各現像液及び現像補充液処方及び各現像処理を表１に示すような組み合わせで現像処理し、平版印刷版を作製した。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（大日本インキ化学工業社製の、大豆油インキ“ナチュラリス１００”）及び湿し水（東京インク（株）製Ｈ液ＳＧ−５１濃度１．５％）を用いて印刷を行った。
【０１６３】
５００ｍ^２印刷後の印刷物の非画像部に、１００ｃｍ^２内の斑点状のインキ汚れを目視にて評価した。
【０１６４】
◎：非画像部にインキ汚れは認められない。
○：非画像部にインキ汚れはほとんど認められない。
【０１６５】
△：非画像部にインキ汚れがわずかに認められるが、印刷物として使用可。
×：非画像部にインキ汚れが認められ、印刷物として使用不可。
【０１６６】
評価結果を表１に示す。
〈スラッジ・ヘドロの評価〉
現像処理廃液漕からのオーバーフロー廃液を自動現像機外に設置した蓋付きの５Ｌの容器に送液ポンプで送り出し、スラッジ・ヘドロの発生状況と発泡の状況を目視で確認した。
【０１６７】
○：容器内にわずかにスラッジ・ヘドロの発生が見られるが、現像される平版印刷版には付着せず実質上問題はない。
【０１６８】
△：容器内にスラッジ・ヘドロ発生が見られ、容器内の清掃作業はスポンジ・ブラシ等での擦りが必要である。
【０１６９】
×：容器内に、ゲル状のスラッジ・へドロが発生し、容器の槽内がゲル化物で流動性が悪くなり、送液ポンプや攪拌スクリューに不具合が生じる。
【０１７０】
評価結果を表１に示す。
【０１７１】
【表１】

【０１７２】
表１より、本発明のものはインキ汚れはほとんどみられず、且つスラッジ・ヘドロの発生についても許容できるものであることがわかる。すなわち、本発明においては、現像液は珪酸塩を全く含有しない（ＳｉＯ_２質量換算で０．０％）ことが望ましいが、珪酸塩をＳｉＯ_２質量換算で０．１％程度であれば問題がないことがわかる。
【０１７３】
（実施例２）
実施例１において、現像処理漕上の空間に存在する空気ではなく、自動現像機の中に存在する空気とした以外は、実施例１と同様に感光性平版印刷版を現像処理したところ、実施例１と同様に本発明のものはインキ汚れはほとんどみられず、且つスラッジ・ヘドロの発生についても許容できるものであった。
【０１７４】
（実施例３）
実施例１において、現像処理廃液漕を自動現像機外近傍に設けて、現像液廃液を用いて脱炭酸ガス化した空気を現像処理漕内に送り込みながら現像処理したところ、実施例１と同様に本発明のものはインキ汚れはほとんどみられず、且つスラッジ・ヘドロの発生についても許容できるものであった。
【０１７５】
（実施例４）
実施例１において、現像処理廃液漕を自動現像機外近傍に設けて、現像液廃液を用いて脱炭酸ガス化した空気を自動現像機内に送り込みながら現像処理したところ、実施例１と同様に本発明のものはインキ汚れはほとんどみられず、且つスラッジ・ヘドロの発生についても許容できるものであった。
【０１７６】
（実施例５）
現像処理直前まで、実施例１〜４と同様な操作を行い、脱炭酸ガス化した空気を自動現像機内若しくは現像処理漕内に送り込んで現像液の劣化を評価したところ、脱炭酸ガス化した空気を送らないで放置した現像液と比べて、現像液の劣化の低減に有意差が認められた。
【０１７７】
【発明の効果】
本発明により、現像液の現像安定性を保ち、且つ、補充液の使用量増大によるコストの上昇や廃液の増大等の問題を同時に解決し、また、非画像部のインキ汚れが改良され、さらにスラッジの発生を抑えた感光性平版印刷版の処理方法及び現像液の劣化低減方法を提供することができた。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for processing a photosensitive lithographic printing plate and a method for reducing deterioration of a developer, and more specifically, a photosensitive lithographic printing plate using an aqueous alkaline developer containing substantially no silicate and having reduced deterioration. And a method for reducing deterioration of an aqueous alkaline developer containing substantially no silicate.
[0002]
[Prior art]
Conventionally, an alkali metal silicate developer has been widely used for developing a photosensitive lithographic printing plate. In the photosensitive layer of a conventional photosensitive lithographic printing plate, an orthoquinonediazide compound is used in combination with a novolac resin, and an alkaline silicate aqueous solution capable of dissolving the novolak resin is used as a developer. Since this developer can dissolve the novolak resin of the photosensitive layer at a pH of about 13, the developer contains a silicate having a good pH buffering property near pH 13, and Stability has been imparted. These developers are described on page 15 of JP-A-8-160633.
[0003]
Developer containing silicate, preferably silicate to SiO₂As a technique for reducing fatigue deterioration due to carbon dioxide gas in the air of a developer containing 0.8 to 8% by mass in terms of conversion, a photosensitive lithographic plate that automatically conveys and develops a photosensitive lithographic printing plate that has undergone image exposure In a printing plate automatic developing machine, there is known a photosensitive lithographic printing plate automatic developing machine provided with a decarbonizing gas processing means for processing a carbon dioxide gas inside the automatic developing machine or in the vicinity of the outside of the automatic developing machine. (For example, refer to Patent Document 1).
[0004]
However, when the developer containing silicate drops in pH due to the dissolution of the photosensitive layer components by development or the incorporation of carbon dioxide in the air, the silicic acid solidifies and becomes sludge and adheres to the developed plate and stains the plate. There is a problem that the burden of cleaning the developer tank increases due to accumulation in the tank. Patent Document 1 does not mention any use of an aqueous alkaline developer substantially free of silicate as a developer.
[0005]
On the other hand, since a photopolymerization type photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization represented by a photopolymer type CTP plate generally does not use a novolak resin, the pH of the developer is 12.5. Therefore, it is not necessary to use a silicate as a pH buffer solution, so that a developer containing no silicate can be designed. Such a developer is described on page 34 of JP-A-2002-251019. However, since it does not contain silicate, which is a good pH buffer, the pH stability of the developer is poor, and developability deterioration occurs due to a decrease in developer pH caused by carbon dioxide in the air. There have been problems such as non-image area contamination. For this reason, it has been dealt with by so-called replenishment over time that replenishes the developer replenisher with a high pH according to the standing time of the developer, but in this case, the increase in the amount of replenisher used increases the cost or increases the waste liquid There is a problem.
[0006]
[Patent Document 1]
JP-A-8-44081 (claims, paragraph number 0032)
[0007]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to solve the above problems, that is, to maintain the development stability of the developer and simultaneously solve the problems such as the increase in cost and increase in waste liquid due to the increase in the amount of replenisher used. Another object of the present invention is to provide a method for processing a photosensitive lithographic printing plate and a method for reducing deterioration of a developing solution in which ink stains in non-image areas are improved and sludge generation is suppressed.
[0008]
[Means for Solving the Problems]
The above object could be achieved by the following means.
[0009]
(1) A photopolymerization type photosensitive lithographic printing plate in which a photopolymerization type photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder is provided on a support, In the processing method of a photosensitive lithographic printing plate, after the exposure, the development processing bowl containing the developer and the development processing waste tank containing the developer waste liquid discharged from the development processing bowl is developed by an automatic developing machine. The developer is a water-based alkaline developer substantially free of silicate, and development processing is performed while forcibly bringing the air present in the automatic processor into contact with the developer waste liquid stored in the development processing waste tank. A method for processing a photosensitive lithographic printing plate, comprising:
[0010]
(2) A photopolymerization type photosensitive lithographic printing plate in which a photopolymerization type photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder is provided on a support, In the processing method of a photosensitive lithographic printing plate, after the exposure, the development processing bowl containing the developer and the development processing waste tank containing the developer waste liquid discharged from the development processing bowl is developed by an automatic developing machine. The developer is a water-based alkaline developer containing substantially no silicate, and the air present in the development processing tank is forcibly brought into contact with the developer waste liquid stored in the development processing tank. A method for processing a photosensitive lithographic printing plate, wherein the development process is performed while circulating the contacted air in the development processing tank.
[0011]
(3) A photopolymerization type photosensitive lithographic printing plate in which a photopolymerization type photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder is provided on a support, In the processing method of a photosensitive lithographic printing plate, after the exposure, the development processing bowl containing the developer and the development processing waste tank containing the developer waste liquid discharged from the development processing bowl is developed by an automatic developing machine. The developer is a water-based alkaline developer containing substantially no silicate, and the development treatment is performed while air decarbonized using the developer waste solution is fed into the development treatment tank. Processing method of photosensitive lithographic printing plate.
[0012]
(4) A photopolymerizable photosensitive lithographic printing plate in which a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator, and a polymer binder is provided on a support, In the processing method of a photosensitive lithographic printing plate, after the exposure, the development processing bowl containing the developer and the development processing waste tank containing the developer waste liquid discharged from the development processing bowl is developed by an automatic developing machine. The developer is a water-based alkaline developer containing substantially no silicate, and development processing is performed while air decarbonized using the developer waste solution is fed into the automatic developing machine. Processing method for sex lithographic printing plates.
[0013]
(5) The method for processing a photosensitive lithographic printing plate as described in any one of (1) to (4), wherein the developer further contains a surfactant having a polyoxyalkylene group.
[0014]
(6) The surfactant having a polyoxyalkylene group is a nonionic surfactant having a molecular weight of 0 to 25% of a saturated alkyl moiety in the entire hydrophobic group (5) Method for processing a photosensitive lithographic printing plate.
[0015]
(7) The surfactant having a polyoxyalkylene group is an anionic surfactant having a molecular weight of 0 to 25% of a saturated alkyl moiety in the entire hydrophobic group. Processing method of photosensitive lithographic printing plate.
[0016]
(8) A photopolymerizable photosensitive lithographic printing plate in which a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator, and a polymer binder is provided on a support, In the method for reducing deterioration of a developer for developing with an automatic developing machine having a developing treatment tank containing a developing solution after the exposure and a developing solution waste liquid containing the developer waste liquid discharged from the developing treatment basket, The developer is a water-based alkaline developer containing substantially no silicate, and the air present in the automatic processor is forced to contact the developer waste liquid stored in the development processing waste tank. A method for reducing deterioration of a developing solution, comprising reducing carbon dioxide in the air existing in an automatic developing machine.
[0017]
(9) A photopolymerization type photosensitive lithographic printing plate in which a photopolymerization type photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder is provided on a support, In the method for reducing deterioration of a developer for developing with an automatic developing machine having a developing treatment tank containing a developing solution after the exposure and a developing solution waste liquid containing the developer waste liquid discharged from the developing treatment basket, The developer is a water-based alkaline developer containing substantially no silicate, and the air present in the development processing tank is forcibly brought into contact with the developer waste liquid stored in the development processing tank. A method for reducing deterioration of a developing solution, characterized in that carbon dioxide in the air existing in the development processing basket is reduced by circulating the contacted air in the development processing basket.
[0018]
(10) A photopolymerization type photosensitive lithographic printing plate in which a photopolymerization type photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator, and a polymer binder is provided on a support, In the method for reducing deterioration of a developer for developing with an automatic developing machine having a developing treatment tank containing a developing solution after the exposure and a developing solution waste liquid containing the developer waste liquid discharged from the developing treatment basket, The developer is a water-based alkaline developer substantially free of silicate, and the developer is deteriorated by feeding air degassed with the developer waste solution into the developing treatment tank. Reduction method.
[0019]
(11) A photopolymerization type photosensitive lithographic printing plate in which a photopolymerization type photosensitive layer comprising a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder is provided on a support, In the method for reducing deterioration of a developer for developing with an automatic developing machine having a developing treatment tank containing a developing solution after the exposure and a developing solution waste liquid containing the developer waste liquid discharged from the developing treatment basket, The developer is a water-based alkaline developer containing substantially no silicate, and the deterioration of the developer is reduced by feeding air decarbonized using the developer waste into the automatic processor. Method.
[0020]
(12) The developer deterioration reducing method according to any one of (8) to (11), wherein the developer contains a surfactant having a polyoxyalkylene group.
[0021]
(13) The surfactant having a polyoxyalkylene group is a nonionic surfactant having a molecular weight of 0 to 25% of a saturated alkyl moiety in the entire hydrophobic group (12) Method for reducing deterioration of developer.
[0022]
(14) The surfactant according to (12), wherein the surfactant having a polyoxyalkylene group is an anionic surfactant having a molecular weight of 0 to 25% of a saturated alkyl moiety in the entire hydrophobic group. Method for reducing developer deterioration.
[0023]
(15) Replacing the air forcedly brought into contact with the aqueous alkaline developer waste solution containing substantially no silicate with the air in the development processing tank containing the aqueous alkaline developer containing substantially no silicate. To reduce the deterioration of the developer.
[0024]
The major feature of the present invention is that the developer is a water-based alkaline developer substantially free of silicate, and the developer discharged from a development processing tank containing a water-based alkaline developer substantially free of silicate. Forcibly bringing the waste liquid into contact with air, absorbing carbon dioxide in the air into the developer waste liquid, and reducing deterioration of the aqueous alkaline developer substantially free of silicate by carbon dioxide, substantially silicate For example, air is forcibly brought into contact with an aqueous alkaline developer waste solution containing no decarbonized gas to replace the decarboxylated air with the air of the developer soot. By adopting such a technology, the development stability of the developer is maintained, and problems such as an increase in cost due to an increase in the amount of replenisher used and an increase in waste liquid are solved at the same time. The present inventors have found that it is possible to provide a method for processing a photosensitive lithographic printing plate and a method for reducing deterioration of a developer which are improved and further suppress the generation of sludge.
[0025]
In the present invention, the developer “substantially does not contain silicate” means that the concentration of silicate contained in the developer is SiO 2.₂It means that the concentration does not exceed 0.3% in terms of mass.
[0026]
In the present invention, “forcibly bringing air into contact with developer waste liquid” means that the developer waste liquid and air are not brought into contact with each other in a static state, but will be described in detail later. It means to be brought into the developer waste liquid and brought into contact with the developer waste liquid.
[0027]
The deterioration of the developing solution means that the alkaline developing solution absorbs carbon dioxide in the air to lower the pH and lose the developing ability, depending on the ability of the photosensitive lithographic printing plate used and the composition of the developing solution. However, in general, there is a high possibility that developability will be adversely affected by a decrease in pH value of 0.5 or more, and stains may occur in non-image areas during printing. Further, when the pH value is decreased by 1.0 or more, insoluble matter such as sludge may be generated in the developer in addition to the stain on the non-image area during printing.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the constituent features of the present invention will be sequentially described.
[0029]
The main components of the photopolymerization type photosensitive layer according to the present invention are a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator, and a polymer binder.
[0030]
<Compound with addition-polymerizable ethylenically unsaturated bond>
Examples of compounds having addition-polymerizable ethylenically unsaturated bonds include general radical-polymerizable monomers, and many compounds having a plurality of addition-polymerizable ethylenic double bonds in a molecule generally used for UV curable resins. Functional monomers and polyfunctional oligomers can be used. Preferred examples include 2-ethylhexyl acrylate, 2-hydroxypropyl acrylate, glycerol acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, tetrahydrofurfuryloxyethyl acrylate, tetrahydrofurfuryloxyhexanolide acrylate, Monofunctional acrylic esters such as acrylate of 1,3-dioxane alcohol ε-caprolactone adduct, 1,3-dioxolane acrylate, or methacrylic acid, itaconic acid in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate , Crotonic acid, maleic acid esters such as ethylene glycol diacrylate, triethylene glycol Diacrylate, pentaerythritol diacrylate, hydroquinone diacrylate, resorcinol diacrylate, hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, hydroxypentylate neopentyl glycol diacrylate, neopentyl glycol adipate di 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-hexanediol Difunctional acrylates such as diacrylates of diglycidyl ethers, or methacrylic acid, itaconic acid, crotonic acid, maleic acid esters such as trimethylolpropane triacrylate in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate Ditrimethylolpropane tetraacrylate, trimethylolethane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexaacrylate ε-caprolactone Additives, pyrogallol triacrylate, propionic acid / dipipe Polyfunctional acrylic acid such as taerythritol triacrylate, propionic acid / dipentaerythritol tetraacrylate, hydroxypivalylaldehyde-modified dimethylolpropane triacrylate, or methacrylic acid in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate , Itaconic acid, crotonic acid, maleic acid ester and the like.
[0031]
Prepolymers can also be used as described above. Examples of the prepolymer include compounds as 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 be preferably used. These prepolymers may be used alone or in combination of two or more, and may be used by mixing with the above-mentioned monomers and / or oligomers.
[0032]
Examples of prepolymers include 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, tetrahydrophthalic acid, and ethylene glycol, propylene glycol, diethylene glycol, propylene oxide, 1,4-butanediol, triethylene glycol, tetraethylene glycol, polyethylene glycol, glycerin, trimethylol Polyester obtained by introducing (meth) acrylic acid into a polyester obtained by combining polyhydric alcohols such as propane, pentaerythritol, sorbitol, 1,6-hexanediol, 1,2,6-hexanetriol Chlorates such as bisphenol A, epichlorohydrin, (meth) acrylic acid, and epoxy acrylates in which (meth) acrylic acid is introduced into an epoxy resin such as phenol novolac, epichlorohydrin, (meth) acrylic acid, such as ethylene glycol, adipine 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 , Trimethylolpropane, propylene glycol, tolylene diisocyanate, 2-hydroxyethyl acrylate In addition, urethane acrylates in which (meth) acrylic acid is introduced into urethane resin, for example, silicone resin acrylates such as polysiloxane acrylate, polysiloxane diisocyanate, 2-hydroxyethyl acrylate, etc., and (meth) acryloyl in oil-modified alkyd resins Examples thereof include prepolymers such as alkyd-modified acrylates having introduced groups and spirane resin acrylates.
[0033]
Also, phosphazene monomer, triethylene glycol, isocyanuric acid EO (ethylene oxide) modified diacrylate, isocyanuric acid EO modified triacrylate, dimethylol tricyclodecane diacrylate, trimethylolpropane acrylic acid benzoate, alkylene glycol type acrylic acid Addition-polymerizable oligomers and prepolymers having monomers such as modified and urethane-modified acrylates and structural units formed from the monomers can be used.
[0034]
Furthermore, examples of the ethylenic monomer that can be used in combination include a phosphate ester compound containing at least one (meth) acryloyl group. The compound is not particularly limited as long as it is a compound in which at least part of the hydroxyl group of phosphoric acid is esterified and has a (meth) acryloyl group.
[0035]
In addition, JP-A-58-212994, 61-6649, 62-46688, 62-48589, 62-173295, 62-187092, 63- 67189, JP-A-1-244891, and the like. Further, “11290 Chemical Products”, Chemical Industry Daily, p. 286-p. 294, “UV / EB Curing Handbook (raw material)”, Kobunshi Publishing Co., p. The compounds described in 11 to 65 can also be suitably used in the present invention. Of these, compounds having two or more acrylic groups or methacryl 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.
[0036]
In addition, it is preferable to use an addition-polymerizable ethylenic double bond-containing monomer containing a tertiary amino group in the molecule. Although there is no particular limitation on the structure, a tertiary amine compound having a hydroxyl group modified with glycidyl methacrylate, methacrylic acid chloride, acrylic acid chloride or the like is preferably used. Specifically, collectable compounds described in JP-A-1-165613, JP-A-1-203413, and JP-A-1-197213 are preferably used.
[0037]
Furthermore, it is preferable to use a reaction product of a polyhydric alcohol containing a tertiary amino group in the molecule, a diisocyanate compound, and a compound containing an ethylenic double bond capable of addition polymerization with a hydroxyl group in the molecule.
[0038]
Examples of the polyhydric alcohol having a tertiary amino group in the molecule include triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, N-tert. -Butyldiethanolamine, N, N-di (hydroxyethyl) aniline, N, N, N ', N'-tetra-2-hydroxypropylethylenediamine, p-tolyldiethanolamine, N, N, N', N'- Tetra-2-hydroxyethylethylenediamine, N, N-bis (2-hydroxypropyl) aniline, allyldiethanolamine, 3- (dimethylamino) -1,2-propanediol, 3-diethylamino-1,2-propanediol N, N-di (n-propyl) amino-2,3-propanediol, N, N-di (iso-propyl) amino-2,3-propanediol, 3- (N-methyl-N-benzylamino) ) -1,2-propanediol and the like, but not limited thereto.
[0039]
Examples of the diisocyanate compound include butane-1,4-diisocyanate, hexane-1,6-diisocyanate, 2-methylpentane-1,5-diisocyanate, octane-1,8-diisocyanate, 1,3-diisocyanate methyl-cyclohexanone. 2,2,4-trimethylhexane-1,6-diisocyanate, isophorone diisocyanate, 1,2-phenylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene-2,4-diisocyanate, tolylene- Examples include 2,5-diisocyanate, tolylene-2,6-diisocyanate, 1,3-di (isocyanatomethyl) benzene, 1,3-bis (1-isocyanato-1-methylethyl) benzene, and the like. Limited to Not.
[0040]
Examples of the compound containing an ethylenic double bond capable of addition polymerization with a hydroxyl group in the molecule include compounds such as MH-1 to MH-13, but are not limited thereto.
[0041]
[Chemical 1]

[0042]
Preferable examples include 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxypropylene-1,3-dimethacrylate, 2-hydroxypropylene-1-methacrylate-3-acrylate, and the like.
[0043]
These reactions can be carried out in the same manner as a method for synthesizing urethane acrylate by a reaction of a normal diol compound, diisocyanate compound, and hydroxyl group-containing acrylate compound.
[0044]
Specific examples of reaction products of polyhydric alcohols containing tertiary amino groups in the molecule, diisocyanate compounds, and compounds containing ethylenic double bonds capable of addition polymerization with hydroxyl groups in the molecule are shown below. Shown in
[0045]
M-1: reaction product of triethanolamine (1 mol), hexane-1,6-diisocyanate (3 mol), 2-hydroxyethyl methacrylate (3 mol) M-2: triethanolamine (1 mol), isophorone Reaction product of diisocyanate (3 mol) and 2-hydroxyethyl acrylate (3 mol)
M-3: Nn-butyldiethanolamine (1 mol), 1,3-bis (1-isocyanato-1-methylethyl) benzene (2 mol), 2-hydroxypropylene-1-methacrylate-3-acrylate (2 mol) of reaction product
M-4: Reaction of Nn-butyldiethanolamine (1 mol), 1,3-di (isocyanatomethyl) benzene (2 mol), 2-hydroxypropylene-1-methacrylate-3-acrylate (2 mol) Product
M-5: Reaction product of N-methyldiethanolamine (1 mol), tolylene-2,4-diisocyanate (2 mol), 2-hydroxypropylene-1,3-dimethacrylate (2 mol)
In addition, acrylates or alkyl acrylates described in JP-A-1-105238 and JP-A-2-127404 can be used.
[0046]
<Photopolymerization initiator>
In the present invention, preferred photopolymerization initiators include bromine compounds having a structure represented by the following general formula (1) or (2), titanocene compounds, monoalkyltriaryl borate compounds and iron arene complex compounds.
[0047]
General formula (1) R₁-CBr₂-(C = O) -R₂
Where R₁Represents a hydrogen atom, a bromine atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, or a cyano group. R₂Represents a monovalent substituent. R₁And R₂May combine to form a ring.
[0048]
General formula (2) CBr₃-(C = O) -XR₃
R₃Represents a monovalent substituent. X is -O-, -NR₄-Represents. R₄Represents a hydrogen atom or an alkyl group. R₃And R₄May combine to form a ring.
[0049]
Examples of the titanocene compound include compounds described in JP-A-63-41483 and JP-A-2-291. Preferred examples include bis (cyclopentadienyl) -Ti-di-chloride, bis (cyclopentadienyl) -Ti-bis-phenyl, bis (cyclopentadienyl) -Ti-bis-2,3, 4,5,6-pentafluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,3,5,6-tetrafluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4 6-trifluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,6-difluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4-difluorophenyl, bis (methylcyclopentadi) Enyl) -Ti-bis-2,3,4,5,6-pentafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis-2,3,5,6 Tetrafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis-2,6-difluorophenyl (IRUGACURE 727L: manufactured by Ciba Specialty Chemicals), bis (cyclopentadienyl) -bis (2,6-difluoro- 3- (Pyrid-1-yl) phenyl) titanium (IRUGACURE784: Ciba Specialty Chemicals), bis (cyclopentadienyl) -bis (2,4,6-trifluoro-3- (pyrid-1-yl) ) Phenyl) titanium bis (cyclopentadienyl) -bis (2,4,6-trifluoro-3- (2-5-dimethylpy-1-yl) phenyl) titanium and the like.
[0050]
Examples of the monoalkyl triaryl borate compound include compounds described in JP-A Nos. 62-150242 and 62-143044. Preferred examples include tetra-n-butylammonium n-butyl-trinaphthalen-1-yl-borate, tetra-n-butylammonium n-butyl-triphenyl-borate, tetra-n-butylammonium n-butyl-tri- (4-tert-Butylphenyl) -borate, Tetra-n-butylammonium n-hexyrootri- (3-chloro-4-methylphenyl) -borate, Tetra-n-butylammonium n-hexylutri- (3-fluorophenyl) -Borate etc. are mentioned.
[0051]
Examples of the iron arene complex compound include compounds described in JP-A-59-219307. Preferable specific examples include η-benzene- (η-cyclopentadienyl) iron hexafluorophosphate, η-cumene- (η-cyclopentadienyl) iron hexafluorophosphate, η-fluorene- (η-cyclopentadi). Enyl) iron hexafluorophosphate, η-naphthalene- (η-cyclopentadienyl) iron hexafluorophosphate, η-xylene- (η-cyclopentadienyl) iron hexafluorophosphate, η-benzene- (η-cyclopenta And dienyl) iron tetrafluoroborate.
[0052]
In addition, any photopolymerization initiator can be used in combination. For example, J. et al. Carbonyl compounds, organic sulfur compounds, persulfides, redox compounds, azo, diazo compounds, halogen compounds, and photoreductive dyes as described in Chapter 5 of “Light Sensitive Systems” by J. Kosar Etc. More specific compounds are disclosed in British Patent 1,459,563.
[0053]
That is, the following can be used as a photopolymerization initiator that can be used in combination.
[0054]
Benzoin derivatives such as benzoin methyl ether, benzoin-i-propyl ether, α, α-dimethoxy-α-phenylacetophenone; benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, 4,4′-bis (dimethyl) Benzophenone derivatives such as amino) benzophenone; thioxanthone derivatives such as 2-chlorothioxanthone and 2-i-propylthioxanthone; anthraquinone derivatives such as 2-chloroanthraquinone and 2-methylanthraquinone; N-methylacridone, N-butylacridone and the like In addition to α, α-diethoxyacetophenone, benzyl, fluorenone, xanthone and uranyl compounds, JP-B-59-1281, JP-A-61-9621 and JP-A-60-60104 Triazine derivatives described in JP-A-59-1504 and JP-A-61-243807; JP-B-43-23684, JP-A-44-6413, JP-A-44-6413, No. 47-1604 and U.S. Pat. No. 3,567,453; diazonium compounds; U.S. Pat. Nos. 2,848,328, 2,852,379 and 2,940,853 Organic azide compounds described in Japanese Patent Publication Nos. 36-22062, 37-13109, 38-18015, and 45-9610; 55-39162; JP-A-59-14023 and “Macromolecules”, Vol. 10, p. 1307 ( 977); azo compounds described in JP-A-59-142205; JP-A-1-54440, European Patents 109,851, 126,712, and “Journal Of Imaging Science (J. Imag. Sci.), Vol. 30, page 174 (1986); (oxo) sulfonium organic compounds described in JP-A-5-213861 and JP-A-5-255347 Boron complexes; transition metal complexes containing transition metals such as ruthenium described in “Coordination Chemistry Review”, 84, 85-277 (1988) and JP-A-2-182701; No. 3-209477 Roh triarylimidazole dimer; carbon tetrabromide, organic halogen compounds in JP 59-107344 JP like.
[0055]
When laser light is used as the light source, a sensitizing dye is preferably added to the photosensitive layer. It is preferable to use a dye having an absorption maximum wavelength in the vicinity of the wavelength of the light source.
[0056]
Examples of compounds for wavelength sensitization from visible light to near infrared include cyanine, phthalocyanine, merocyanine, porphyrin, spiro compound, ferrocene, fluorene, fulgide, imidazole, perylene, phenazine, phenothiazine, polyene, azo compound, diphenylmethane, triphenyl Ketone alcohol borate complexes such as methane, polymethine acridine, coumarin, coumarin derivatives, ketocoumarin, quinacridone, indigo, styryl, pyrylium compounds, pyromethene compounds, pyrazolotriazole compounds, benzothiazole compounds, barbituric acid derivatives, thiobarbituric acid derivatives, etc. Further, European Patent No. 568,993, U.S. Pat. No. 4,508,811, No. 5,227,227, JP-A-2001-1252. 5 discloses, compounds described in JP-A 11-271969 Patent Publication also used.
[0057]
Specific examples of the combination of the photopolymerization initiator and the sensitizing dye include combinations described in JP-A Nos. 2001-125255 and 11-271969.
[0058]
Although the compounding quantity of these polymerization initiators is not specifically limited, Preferably, it is 0.1-20 mass parts with respect to 100 mass parts of compounds which have an ethylenically unsaturated bond in which addition polymerization is possible. The mixing ratio of the photopolymerization initiator and the sensitizing dye is preferably in the range of 1: 100 to 100: 1 in terms of molar ratio.
[0059]
<Polymer binder>
Examples of the polymer binder include acrylic polymer, polyvinyl butyral resin, polyurethane resin, polyamide resin, polyester resin, epoxy resin, phenol resin, polycarbonate resin, polyvinyl butyral resin, polyvinyl formal resin, shellac, and other natural resins. Can be used. Two or more of these may be used in combination.
[0060]
A vinyl copolymer obtained by copolymerization of acrylic monomers is preferred. The copolymer composition of the polymer binder is preferably a copolymer of (a) carboxyl group-containing monomer, (b) methacrylic acid alkyl ester, or acrylic acid alkyl ester.
[0061]
Specific examples of the carboxyl group-containing monomer include α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride and the like. In addition, carboxylic acids such as phthalic acid and 2-hydroxymethacrylate half ester are also preferable. Specific examples of alkyl methacrylates and alkyl esters include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate. , Decyl methacrylate, undecyl methacrylate, dodecyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, acrylic In addition to unsubstituted alkyl esters such as decyl acid, undecyl acrylate and dodecyl acrylate, cyclic alkyl esters such as cyclohexyl methacrylate and cyclohexyl acrylate Substituted alkyl esters such as benzyl methacrylate, 2-chloroethyl methacrylate, N, N-dimethylaminoethyl methacrylate, glycidyl methacrylate, benzyl acrylate, 2-chloroethyl acrylate, N, N-dimethylaminoethyl acrylate, and glycidyl acrylate Also mentioned.
[0062]
Furthermore, in the polymer binder of the present invention, monomers described in the following 1) to 14) can be used as other copolymerization monomers.
[0063]
1) Monomers having an aromatic hydroxyl group, such as o- (or p-, m-) hydroxystyrene, o- (or p-, m-) hydroxyphenyl acrylate and the like.
[0064]
2) Monomers having an aliphatic hydroxyl group, such as 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.
[0065]
3) A monomer having an aminosulfonyl group, such as m- (or p-) aminosulfonylphenyl methacrylate, m- (or p-) aminosulfonylphenyl acrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p -Aminosulfonylphenyl) acrylamide and the like.
[0066]
4) Monomers having a sulfonamide group, such as N- (p-toluenesulfonyl) acrylamide, N- (p-toluenesulfonyl) methacrylamide and the like.
[0067]
5) Acrylamide or methacrylamides such as 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.
[0068]
6) Monomers containing fluorinated alkyl groups such as trifluoroethyl acrylate, trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, hexafluoropropyl methacrylate, octafluoropentyl acrylate, octafluoropentyl methacrylate, heptadecafluorodecyl methacrylate, N- Butyl-N- (2-acryloxyethyl) heptadecafluorooctylsulfonamide and the like.
[0069]
7) Vinyl ethers such as ethyl vinyl ether, 2-chloroethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether and the like.
[0070]
8) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate and the like.
[0071]
9) Styrenes such as styrene, methyl styrene, chloromethyl styrene and the like.
[0072]
10) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, and phenyl vinyl ketone.
[0073]
11) Olefins such as ethylene, propylene, i-butylene, butadiene, isoprene and the like.
[0074]
12) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine and the like.
[0075]
13) Monomers having a cyano group, such as acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, o- (or m-, p-) cyanostyrene.
[0076]
14) A monomer having an amino group, such as 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.
[0077]
Other monomers that can be copolymerized with these monomers may be copolymerized. Furthermore, an unsaturated bond-containing vinyl copolymer obtained by addition-reacting a compound having a (meth) acryloyl group and an epoxy group in the molecule to a carboxyl group present in the molecule of the vinyl copolymer. Is also preferred as a polymer binder. Specific examples of the compound containing both an unsaturated bond and an epoxy group in the molecule include glycidyl acrylate, glycidyl methacrylate, and an epoxy group-containing unsaturated compound described in JP-A No. 11-271969.
[0078]
These copolymers preferably have a weight average molecular weight of 1 to 200,000 as measured by gel permeation chromatography (GPC), but are not limited to this range.
[0079]
The content of the polymer binder in the photopolymerization type photosensitive layer is preferably in the range of 10 to 90% by mass, more preferably in the range of 15 to 70% by mass, and the sensitivity to use in the range of 20 to 50% by mass. Particularly preferred from the viewpoint.
[0080]
The acid value of the polymer binder is preferably used in the range of 10 to 150, more preferably in the range of 30 to 120, and in the range of 50 to 90, the polarity of the entire photopolymerization type photosensitive layer. This is particularly preferable from the viewpoint of balancing. Thereby, when a pigment is contained in the photopolymerization type photosensitive layer coating solution, aggregation of the pigment can be prevented.
[0081]
<Support>
As the support, any support that can be used with a photosensitive lithographic printing plate can be used. In the present invention, an aluminum plate is preferable.
[0082]
The aluminum support is obtained from an aluminum plate material using pure aluminum or an aluminum support material using an aluminum alloy. As the aluminum plate material using an aluminum alloy, for example, an alloy of aluminum and a metal such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, nickel, titanium, sodium, and iron is used. The surface has a rough surface shape of a double structure in which small pits are superimposed on large undulations.
[0083]
The aluminum plate is usually used after degreasing with an alkali, an acid, a solvent or the like in order to remove oil used during rolling and winding existing on the surface. As the degreasing treatment, degreasing with an alkaline aqueous solution is particularly preferable. Moreover, in order to improve adhesiveness with a coating layer, it is preferable to perform an easily bonding process and undercoat layer application | coating to an application surface. For example, there may be mentioned a method of immersing in a liquid containing a coupling agent such as a silane coupling agent or applying a liquid and then sufficiently drying. Anodizing treatment is also considered as a kind of easy adhesion treatment and can be used. Moreover, it can also be used combining an anodizing process and the said immersion or application | coating process. Moreover, the aluminum plate roughened by the well-known method can also be used.
[0084]
<Other configuration as photosensitive lithographic printing plate>
The photosensitive lithographic printing plate according to the present invention can be provided with an oxygen barrier layer. As the oxygen barrier layer, a water-soluble polymer capable of forming a film having low oxygen permeability is used. Specifically, it contains polyvinyl alcohol and polyvinyl pyrrolidone. Polyvinyl alcohol has an effect of suppressing permeation of oxygen, and polyvinyl pyrrolidone has an effect of ensuring adhesion with an adjacent photosensitive layer.
[0085]
In addition to the above two polymers, polysaccharides, polyethylene glycol, gelatin, glue, casein, hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose, hydroxyethyl starch, gum arabic, sucrose octaacetate, ammonium alginate, sodium alginate as required Water-soluble polymers such as polyvinylamine, polyethylene oxide, polystyrene sulfonic acid, polyacrylic acid, and water-soluble polyamide can also be used in combination.
[0086]
The photosensitive lithographic printing plate according to the present invention can be provided with an overcoat layer. The peeling force between the photopolymerization type photosensitive layer and the overcoat layer is preferably 35 g / 10 mm or more, more preferably 50 g / 10 mm or more, still more preferably 75 g / 10 mm or more. The peeling force is the force when an adhesive tape of a predetermined width having a sufficiently large adhesive force is applied on the overcoat layer and peeled off with the overcoat layer at an angle of 90 degrees with respect to the plane of the photosensitive lithographic printing plate. taking measurement.
[0087]
Preferred overcoat layer compositions include those described in JP-A-10-10742. The overcoat layer can further contain a surfactant, a matting agent and the like as required. The overcoat layer composition is dissolved in a suitable solvent, applied onto the photosensitive layer and dried to form an overcoat layer. The main component of the coating solvent is particularly preferably water or alcohols such as methanol, ethanol, i-propanol. The thickness of the overcoat layer is preferably from 0.1 to 5.0 μm, particularly preferably from 0.5 to 3.0 μm.
[0088]
The developer according to the present invention is an aqueous alkaline developer substantially free of silicate. In the present invention, the developer according to the present invention preferably contains a surfactant having a polyoxyalkylene group.
[0089]
The developer according to the present invention will be described below.
<Alkaline agent>
The developer according to the present invention preferably contains no silicate. Even if silicate is contained, the concentration of silicate contained in the developer is SiO 2₂The concentration does not exceed 0.3% in terms of mass.
[0090]
The main component of the developer and replenisher in the present invention is at least one compound selected from phosphoric acid, carbonic acid, boric acid, phenols, saccharides, oximes and fluorinated alcohols, or an alkali metal salt or organic cation salt thereof. It is preferable to contain. These compounds should be used in the form of an alkaline aqueous solution having a pH higher than 8.5 and lower than 13.0 by coexisting with an alkali metal hydroxide such as sodium hydroxide, potassium hydroxide or lithium hydroxide. Is preferred. More preferably, the pH is 8.5-12.
[0091]
Among these, as weakly acidic substances such as phenols, saccharides, oximes and fluorinated alcohols, those having a dissociation index (pKa) of 10.0 to 13.2 are preferable. Such an acid is selected from those described in IONISATION CONSTANTS OF ORGANIC ACIDS INAQUEOUS SOLUTION published by Pergamon Press, and specifically, salicylic acid (pKa13.0), 3-hydroxy-2-naphthoic acid ( 12.84), catechol (12.6), gallic acid (12.4), sulfosalicylic acid (11.7), 3,4-dihydroxysulfonic acid (12.2), 3,4- Dihydroxybenzoic acid (11.94), 1,2,4-trihydroxybenzene (11.82), hydroquinone (11.56), pyrogallol (11.34), o-cresol (10.33) ), Resorsonol (11.27), p-cresol (10. 7), m-cresol (phenol having a phenolic hydroxyl group, such as the 10.09) and the like.
[0092]
As the saccharide, a non-reducing sugar that is stable even in an alkali is preferably used. Such non-reducing sugars are saccharides that do not have a free aldehyde group or ketone group and do not exhibit reducing properties, and are trehalose-type oligosaccharides in which reducing groups are bonded to each other, and glycosides in which a reducing group of saccharides and non-saccharides are bonded. These are classified into sugar alcohols reduced by hydrogenation of the body and saccharides, both of which are preferably used in the present invention. Trehalose type oligosaccharides include saccharose and trehalose. Examples of glycosides include alkyl glycosides, phenol glycosides, mustard oil glycosides, and the like. Examples of the sugar alcohol include D, L-arabit, rebit, xylit, D, L-sorbit, D, L-mannit, D, L-exit, D, L-talit, durisit and allozulcit. Furthermore, maltitol obtained by hydrogenation of a disaccharide and a reduced form (reduced water candy) obtained by hydrogenation of an oligosaccharide are preferably used. Furthermore, 2-butanone oxime (pKa 12.45), acetoxime (12.42), 1.2-cycloheptanedione oxime (12.3), 2-hydroxybenzaldehyde oxime (12.10), dimethylglycol Oximes such as oxime (11.9), ethanediamide dioxime (11.37), acetophenone oxime (11.35), such as 2,2,3,3-tetrafluoropropanol-1 (12. 74), fluorinated alcohols such as trifluoroethanol (12.37) and trichloroethanol (12.24). In addition, aldehydes such as pyridine-2-aldehyde (12.68) and pyridine-4-aldehyde (12.05), adenosine (12.56), inosine (12.5), guanine ( 12.3), nucleic acid-related substances such as cytosine (12.2), hypoxanthine (12.1), xanthine (11.9), diethylaminomethylsulfonic acid (12.32), 1-amino-3,3,3-trifluorobenzoic acid (12.29), isopropylidenedisulfonic acid (12.10), 1,1-ethylidene diphosphonic acid (11.54), 1,1 -1-hydroxyethylidene disulfonate (11.52), benzimidazole (12.86), thiobenzamide (12.8), picolinethioamide (12.55), barbi Include weak acid, such as Le acid (same 12.5). These acidic substances may be used alone or in combination of two or more.
[0093]
Among these acidic substances, phosphoric acid, carbonic acid, sulfosalicylic acid, salicylic acid, and sugar alcohols and saccharose of non-reducing sugar are preferable, and D-sorbite, saccharose, and reduced starch candy have a buffering action in an appropriate pH range. That is preferable because of its low price.
[0094]
The proportion of these acidic substances in the developer is preferably from 0.1 to 30% by mass, and more preferably from 1 to 20% by mass. Below this range, a sufficient buffering effect cannot be obtained, and when the concentration is above this range, it is difficult to achieve high concentration, and the problem of increased costs arises. As the base to be combined with these acids, sodium hydroxide, ammonium, potassium and lithium are preferably used. These alkali agents are used alone or in combination of two or more. When the pH of the developer is 8.5 or less, the image portion of the printing plate obtained from the photosensitive lithographic printing plate that can be developed with such a developer is physically fragile, and the wear during printing is fast and sufficient. Printing durability cannot be obtained. Further, the image portion is chemically weak, and an image of a portion wiped with an ink washing solvent or a plate cleaner is damaged during printing, and as a result, sufficient chemical resistance cannot be obtained. A developer having a high pH such that the pH exceeds 13.0 is highly irritating when adhering to the skin or mucous membrane, and is not preferable because it requires sufficient care in handling.
[0095]
Other examples include tripotassium phosphate, trisodium phosphate, trilithium phosphate, triammonium phosphate, dipotassium phosphate, disodium phosphate, dilithium phosphate, diammonium phosphate, potassium carbonate, sodium carbonate, lithium carbonate, ammonium carbonate, carbonate Examples include potassium hydrogen carbonate, sodium hydrogen carbonate, lithium hydrogen carbonate, ammonium hydrogen carbonate, potassium borate, sodium borate, lithium borate, ammonium borate and the like, and may be added in the form of a preformed salt. Again, sodium hydroxide, ammonium, potassium and lithium can be added to the pH adjustment. Moreover, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, Organic alkali agents such as ethyleneimine, ethylenediamine, and pyridine are also used in combination.
[0096]
The developer referred to in the present invention is not only an unused solution that is used at the start of development, but also a replenisher that is replenished in order to correct the activity of the developer that decreases due to the processing of the photosensitive lithographic printing plate. In addition, a liquid whose activity is maintained (so-called running liquid) is included. The replenisher therefore needs to have a higher activity (alkali concentration) than the developer, so the pH of the replenisher may exceed 13.0.
[0097]
<Surfactant>
The developer according to the present invention preferably contains a surfactant having a polyoxyalkylene group. By adding this surfactant, dissolution of the photosensitive layer in the unexposed area can be promoted and the permeability of the developer into the exposed area can be reduced. As a surfactant having a polyoxyalkylene group, a nonionic surfactant (surfactant A) having a molecular weight of 0 to 25% of the saturated alkyl moiety in the entire hydrophobic group, or saturated in the entire hydrophobic group. An anionic surfactant (surfactant B) having a molecular weight ratio of 0 to 25% is preferred.
[0098]
(Surfactant A)
Surfactant A has a nonoxygen group having a polyoxyalkylene group in which the ratio of the saturated alkyl moiety in the entire hydrophobic group is 0 to 25% in molecular weight (that is, the ratio of the saturated alkyl moiety in the hydrophobic group is 0 to 25%). It refers to an ionic surfactant and is preferably 0 to 5% of the molecular weight of the entire hydrophobic group.
[0099]
Here, “the proportion of the saturated alkyl moiety in the entire hydrophobic group is 0 to 25% in molecular weight” means that when the molecule has two or more hydrophobic groups having a saturated alkyl moiety, all of the molecules possessed by the molecule The results are calculated in% as a result of calculation using the total molecular weight of the hydrophobic group elements as the denominator and the molecular weight of the saturated alkyl moiety elements of all the hydrophobic groups as the numerator (saturated alkyl part). In this case, when the molecule has several hydrophobic groups, it is preferable that each hydrophobic group averages “the ratio of the saturated alkyl moiety in the entire hydrophobic group is 0 to 25% in molecular weight”. Those having an average of hydrophobic groups not in the above range are also useful.
[0100]
The total molecular weight of the hydrophobic group elements preferably has a certain size, and preferably has a molecular weight of about 120 to 2,000.
[0101]
Next, although the preferable example of surfactant A is given, in this invention, it is not limited to these. In addition,% in () represents the ratio of the saturated alkyl part to the whole said hydrophobic group.
[0102]
[Chemical formula 2]

[0103]
[Chemical Formula 3]

[0104]
Surfactant A is preferably contained in the developer in an amount of 0.1 to 10% by mass, and more preferably 0.5 to 5.0% by mass.
[0105]
(Surfactant B)
Surfactant B is an anion having a polyoxyalkylene group in which the proportion of the saturated alkyl moiety in the entire hydrophobic group is 0 to 25% in molecular weight (that is, the ratio of the saturated alkyl moiety in the hydrophobic group is 0 to 25%). It is preferably a surfactant having a molecular weight of 0 to 5% of the entire hydrophobic group.
[0106]
Here, “the ratio of the saturated alkyl moiety in the entire hydrophobic group is 0 to 25% in terms of molecular weight” is synonymous with the surfactant A.
[0107]
Next, although the preferable example of surfactant B is given, in this invention, it is not limited to these. In addition,% in () represents the ratio of the saturated alkyl part to the whole said hydrophobic group.
[0108]
[Formula 4]

[0109]
[Chemical formula 5]

[0110]
Surfactant B is preferably contained in the developer in an amount of 0.1 to 10% by mass, and more preferably 0.5 to 5.0% by mass.
[0111]
Further, in the surfactant A and the surfactant B described above, if the molecular weight of the hydrophobic group is too small, the dissolving ability at the time of development of the photopolymerization type photosensitive layer of the photosensitive lithographic printing plate is lowered, and sludge and sludge are generated. On the other hand, if the molecular weight of the hydrophobic group is too large, the solubility of these compounds in the developer becomes poor, and it becomes difficult to produce and maintain a uniform developer.
[0112]
The developer according to the present invention may contain known additives as necessary.
(Surfactant)
To the developer and replenisher used in the present invention, various surfactants and organic solvents can be added as necessary for the purpose of promoting developability, dispersing development residue, and improving ink affinity of the printing plate image area. Preferred surfactants include anionic, cationic, nonionic and amphoteric surfactants.
[0113]
Preferred examples of the surfactant include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene polystyryl phenyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, glycerin fatty acid partial esters, sorbitan Fatty acid partial esters, pentaerythritol fatty acid partial esters, propylene glycol mono fatty acid esters, sucrose fatty acid partial esters, polyoxyethylene sorbitan fatty acid partial esters, polyoxyethylene sorbitol fatty acid partial esters, polyethylene glycol fatty acid esters, poly Glycerin fatty acid partial esters, polyoxyethylenated castor oil, polyoxyethylene glycerin fatty acid partial esters, polio Siethylene-polyoxypropylene block copolymer, ethylenediamine polyoxyethylene-polyoxypropylene block copolymer adduct, fatty acid diethanolamides, N, N-bis-2-hydroxyalkylamines, polyoxyethylene alkylamine, Nonionic surfactants such as triethanolamine fatty acid esters and trialkylamine oxides, fatty acid salts, abietic acid salts, hydroxyalkane sulfonic acid salts, alkane sulfonic acid salts, dialkyl sulfosuccinic acid ester salts, linear alkylbenzene sulfonic acid salts Branched alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl diphenyl ether sulfonates, alkylphenoxy polyoxyethylene propyl sulfonates, Lioxyethylene alkylsulfophenyl ether salts, N-methyl-N-oleyl taurine sodium salt, N-alkylsulfosuccinic acid monoamide disodium salt, petroleum sulfonates, sulfated beef oil, sulfate esters of fatty acid alkyl esters, alkyl Sulfuric acid ester salts, polyoxyethylene alkyl ether sulfuric acid ester salts, fatty acid monoglyceride sulfuric acid ester salts, polyoxyethylene alkylphenyl ether sulfuric acid ester salts, polyoxyethylene styryl phenyl ether sulfuric acid ester salts, alkyl phosphoric acid ester salts, polyoxyethylene alkyl ether Phosphoric acid ester salts, polyoxyethylene alkylphenyl ether phosphoric acid ester salts, partially saponified products of styrene / maleic anhydride copolymer, olefin / none Anionic surfactants such as partially saponified products of water maleic acid copolymer, naphthalene sulfonate formalin condensates, alkylamine salts, quaternary ammonium salts such as tetrabutylammonium bromide, polyoxyethylene alkylamine salts, Examples include cationic surfactants such as polyethylene polyamine derivatives, and amphoteric surfactants such as carboxybetaines, aminocarboxylic acids, sulfobetaines, aminosulfuric esters, and imidazolines. Among the surfactants listed above, those having polyoxyethylene can be read as polyoxyalkylenes such as polyoxymethylene, polyoxypropylene and polyoxybutylene, and these surfactants are also included. A more preferred surfactant is a fluorosurfactant containing a perfluoroalkyl group in the molecule. Such fluorosurfactants include perfluoroalkyl carboxylates, perfluoroalkyl sulfonates, anionic types such as perfluoroalkyl phosphates, amphoteric types such as perfluoroalkyl betaines, and perfluoroalkyltrimethylammonium salts. Cationic and perfluoroalkylamine oxides, perfluoroalkyl ethylene oxide adducts, perfluoroalkyl group and hydrophilic group-containing oligomers, perfluoroalkyl group and lipophilic group-containing oligomers, perfluoroalkyl groups, hydrophilic groups and lipophilic groups Nonionic types such as group-containing oligomers, perfluoroalkyl groups, and lipophilic group-containing urethanes can be mentioned.
[0114]
Said surfactant can be used individually or in combination of 2 or more types, and is added in 0.001-10 mass% in a developing solution, More preferably, it is added in 0.01-5 mass%.
[0115]
(Development stabilizer)
A development stabilizer is preferably used for the developer and replenisher used in the present invention. Preferred examples thereof include polyethylene glycol adducts of sugar alcohols described in JP-A-6-282079, tetraalkylammonium salts such as tetrabutylammonium hydroxide, phosphonium salts such as tetrabutylphosphonium bromide, and iodonium such as diphenyliodonium chloride. A salt is a preferred example. Further, anionic surfactants or amphoteric surfactants described in JP-A-50-51324, water-soluble cationic polymers described in JP-A-55-95946, and JP-A-56-142528 are described. And water-soluble amphoteric polymer electrolytes. Further, an organoboron compound to which an alkylene glycol is added as described in JP-A-59-84241, a polyoxyethylene-polyoxypropylene block polymerization type water-soluble surfactant as described in JP-A-60-111246, An alkylenediamine compound substituted with polyoxyethylene-polyoxypropylene disclosed in JP-A-60-129750, a polyethylene glycol having a weight average molecular weight of 300 or more described in JP-A-61-215554, and a cation described in JP-A-63-175858 And a water-soluble ethylene oxide addition compound obtained by adding 4 mol or more of ethylene oxide to an acid or alcohol disclosed in JP-A-2-39157, a water-soluble polyalkylene compound, and the like.
[0116]
(Organic solvent)
If necessary, an organic solvent is added to the developer and the development replenisher. As the organic solvent, those having a solubility in water of about 10% by mass or less are suitable, and preferably selected from those having 5% by mass or less. For example, 1-phenylethanol, 2-phenylethanol, 3-phenyl-1-propanol, 4-phenyl-1-butanol, 4-phenyl-2-butanol, 2-phenyl-1-butanol, 2-phenoxyethanol, 2- Benzyloxyethanol, o-methoxybenzyl alcohol, m-methoxybenzyl alcohol, p-methoxybenzyl alcohol, benzyl alcohol, cyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol and 4-methylcyclohexanol, N-phenylethanol Examples thereof include amines and N-phenyldiethanolamine.
[0117]
The content of the organic solvent is 0.1 to 5% by mass with respect to the total mass of the liquid used, but it is preferably substantially not contained, and particularly preferably not contained at all. Here, “substantially not contained” means 1% by mass or less.
[0118]
(Reducing agent)
A reducing agent is added to the developer and replenisher used in the present invention as necessary. This prevents stains on the printing plate, and is particularly effective when developing a negative photosensitive lithographic printing plate containing a photosensitive diazonium salt compound. Preferable organic reducing agents include phenol compounds such as thiosalicylic acid, hydroquinone, metol, methoxyquinone, resorcin, and 2-methylresorcin, and amine compounds such as phenylenediamine and phenylhydrazine.
[0119]
More preferable inorganic reducing agents include sodium, potassium and ammonium salts of inorganic acids such as sulfurous acid, bisulfite, phosphorous acid, hydrogen phosphite, dihydrogen phosphite, thiosulfuric acid and dithionite. A salt etc. can be mentioned. Among these reducing agents, sulfites are particularly excellent in the antifouling effect. These reducing agents are preferably contained in the range of 0.05 to 5% by mass with respect to the developer at the time of use.
[0120]
(Organic carboxylic acid)
If necessary, an organic carboxylic acid can be further added to the developer and replenisher used in the present invention. Preferred organic carboxylic acids include aliphatic carboxylic acids and aromatic carboxylic acids having 6 to 20 carbon atoms.
[0121]
Specific examples of the aliphatic carboxylic acid include caproic acid, enanthylic acid, caprylic acid, lauric acid, myristic acid, palmitic acid and stearic acid, and particularly preferred are alkanoic acids having 8 to 12 carbon atoms. . Further, it may be an unsaturated fatty acid having a double bond in the carbon chain or a branched carbon chain. The aromatic carboxylic acid is a compound in which a carboxyl group is substituted on a benzene ring, naphthalene ring, anthracene ring or the like, and specifically includes o-chlorobenzoic acid, p-chlorobenzoic acid, o-hydroxybenzoic acid, p- Hydroxybenzoic acid, o-aminobenzoic acid, p-aminobenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 3, There are 5-dihydroxybenzoic acid, gallic acid, 1-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, 2-hydroxy-1-naphthoic acid, 1-naphthoic acid, 2-naphthoic acid and the like. Naphthoic acid is particularly effective. The aliphatic and aromatic carboxylic acids are preferably used as sodium salts, potassium salts or ammonium salts in order to enhance water solubility.
[0122]
The content of the organic carboxylic acid in the developer used in the present invention is not particularly limited, but if it is less than 0.1% by mass, the effect may not be sufficient, and if it is 10% by mass or more, the effect is further improved. In some cases, it is not observed, and therefore, the preferable addition amount is 0.1 to 10% by mass, and more preferably 0.5 to 4% by mass with respect to the developing solution in use.
[0123]
(Other additives)
In addition to the above, the following additives can be added to the developer and replenisher used in the present invention in order to improve the development performance. For example, neutral salts such as NaCl, KCl, KBr described in JP-A-58-75152, and [Co (NH₃]]₆Cl₃, Amphoteric polymer electrolytes such as a copolymer of vinylbenzyltrimethylammonium chloride and sodium acrylate described in JP-A-56-142258, Si, Ti, etc. described in JP-A-59-75255 Examples thereof include organometallic surfactants and organoboron compounds described in JP-A-59-84241. The developer and replenisher used in the present invention may further contain a preservative, a colorant, a thickener, an antifoaming agent, a hard water softener, and the like, if necessary. Examples of the antifoaming agent include mineral oil, vegetable oil, alcohol, surfactant, silicone and the like described in JP-A-2-244143. Examples of the water softener include polyphosphoric acid and its sodium salt, potassium salt and ammonium salt, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraminehexaacetic acid, hydroxyethylethylenediaminetriacetic acid, nitrilotriacetic acid, 1,2-diaminocyclohexanetetra Aminopolycarboxylic acids such as acetic acid and 1,3-diamino-2-propanoltetraacetic acid and their sodium, potassium and ammonium salts, aminotri (methylenephosphonic acid), ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylene Phosphonic acid), triethylenetetramine hexa (methylenephosphonic acid), hydroxyethylethylenediaminetri (methylenephosphonic acid) and - hydroxyethane-1,1-diphosphonic acid and their sodium salts, potassium salts and ammonium salts.
[0124]
The optimum value of such a hard water softening agent varies depending on its chelating power, the hardness of the hard water used and the amount of hard water. % By mass, more preferably in the range of 0.01 to 0.5% by mass.
[0125]
(Concentrated liquid)
It is advantageous in terms of transportation that the developer and replenisher used in the present invention are concentrated solutions in which the water content is less than in use, and diluted with water during use. The degree of concentration in this case is appropriate so that each component does not separate or precipitate, but it is preferable to add a solubilizing agent if necessary. As such a solubilizer, a so-called hydrotrope such as toluenesulfonic acid, xylenesulfonic acid and alkali metal salts thereof described in JP-A-6-32081 is preferably used. The content of water in the concentrate can be further reduced to form a solid or paste. In this case, the developer may be once evaporated and then evaporated to dryness, but it is preferable that the concentrated state is obtained by mixing the materials without adding water when adding a plurality of materials or by adding a small amount of water. Is preferred. Further, this developer concentrate is disclosed in JP-A-51-61837, JP-A-2-109042, JP-A-2-109043, JP-A-3-39735, JP-A-5-142786, JP-A-6-266062, JP-A-7-2 Granules and tablets can be obtained by a conventionally well-known method described in US Pat. The material contained in the solid or paste developer concentrate can use the components used in the developer of ordinary photosensitive lithographic printing plates, but it does not return to its original state even if diluted with water. Is preferably not included. For example, since silicate is converted into stone when it becomes low in moisture, it becomes difficult to dissolve in water. Therefore, it is preferable to contain carbonate, phosphate, organic acid salt or the like instead of silicate.
[0126]
These developer concentrates or solid or paste concentrates may be divided into a plurality of parts having different material types, material mixing ratios, and the like. These concentrated developer concentrates are preferably used for development after dilution to a predetermined concentration with water before development. In addition, when this developer concentrate or concentrate is used as a developer replenisher, it is most preferable to dilute with water to a predetermined concentration and then add it to the developer in use. It is also possible to put it in a developing solution as it is without diluting to a predetermined concentration. When adding the developer concentrate to a developing solution in use at a concentration higher than a predetermined concentration or without diluting to a predetermined concentration, water is added directly to the developing solution in use at the same timing or at another timing. May be added.
[0127]
<exposure>
For example, a carbon arc lamp, a high-pressure mercury lamp, a xenon lamp, a metal halide lamp, a fluorescent lamp, a tungsten lamp, a halogen lamp, a helium cadmium laser, an argon ion laser, an FD / YAG laser, An image can be formed on the surface of the support by image development with a conventionally known actinic ray such as a helium neon laser or a semiconductor laser (350 nm to 600 nm), followed by development. In order to increase the curing rate of the photopolymerizable photosensitive layer after image exposure and before development, a heating process may be performed at a temperature of 50 ° C. to 150 ° C. for 1 second and 5 minutes.
[0128]
<Automatic processor>
It is essential that the automatic developing machine used in the present invention has a development processing tank for storing the developer and a development processing liquid tank for storing the developer waste liquid discharged from the development processing tank. In the present invention, the development processing waste liquid tank may be installed in the automatic processor or in the vicinity of the outside of the automatic processor.
[0129]
In addition to this essential mechanism, it is possible to have an arbitrary mechanism provided in an automatic processor applied to the processing of a photosensitive lithographic printing plate. For example, a mechanism for automatically replenishing a required amount of replenisher is preferably provided in the developer tank. Further, preferably a mechanism for automatically replenishing the developer tank with a necessary amount of water is provided, and preferably a mechanism for detecting the passage of the photosensitive lithographic printing plate (detection of plate passing) is provided, Preferably, a mechanism for estimating the processing area of the plate based on the detection of the plate is provided, and preferably a replenisher to be replenished based on the detection of the plate and / or the estimation of the processing area and / or A mechanism for controlling the replenishment amount and / or replenishment timing of water is provided, preferably a mechanism for controlling the temperature of the developer is provided, and preferably a mechanism for detecting the pH and / or conductivity of the developer. Preferably, a mechanism for controlling the replenishment amount and / or replenishment timing of the replenisher and / or water to be replenished based on the pH and / or conductivity of the developer is provided. That. Moreover, when there exists a washing process after a image development process, the washing water after use can be used as a dilution water of the concentrate of a development concentrate and a development replenisher.
[0130]
The automatic processor used in the present invention may have a pretreatment unit that immerses the plate in the pretreatment liquid before the development step. The pretreatment unit is preferably provided with a mechanism for spraying the pretreatment liquid onto the plate surface, and preferably provided with a mechanism for controlling the temperature of the pretreatment liquid to an arbitrary temperature of 25 ° C to 55 ° C. Preferably, a mechanism for rubbing the plate surface with a roller-like brush is provided. Moreover, water etc. are used as this pretreatment liquid.
[0131]
The automatic processor used in the present invention preferably has a function of replenishing water in order to compensate for the evaporation of water in the developer. If the automatic processor has a water supply mechanism for diluting the concentrated developer, it may be used. A method of replenishing water determined per hour is the simplest and preferable method for replenishing water. However, the water replenishment amount may be corrected based on measured values from sensors such as pH of the developer and electric power. Further, the replenishment amount of water may be corrected using the temperature and / or humidity of the outside air, the temperature of the developer, the temperature and / or humidity of the air in the automatic developing machine, and the like.
[0132]
<Development processing>
There are basically four examples of the processing method of the photosensitive lithographic printing plate of the present invention. First, development processing is carried out while forcibly bringing the air present in the automatic developing machine into contact with the developer waste liquid stored in the development processing waste tank (second aspect of the invention), and the second is the development processing tank. Forcibly bringing the air present in the developer waste liquid contained in the development waste liquid tank into contact with the developer, and then developing while circulating the contacted air in the development waste tank (invention of claim 2), Thirdly, the development process is carried out while air decarbonized using the developer waste liquid is sent into the development tank (the invention according to claim 3), and the fourth is the decarbonation gas using the developer waste liquid. The development process is performed while feeding the converted air into the automatic developing machine (the invention according to claim 4).
[0133]
As a method for forcing air into contact with the developer waste liquid stored in the development processing waste liquid tank, there is a method of bringing air into the developer waste liquid and bringing it into contact with the developer waste liquid by the following physical means.
[0134]
1) Contact is promoted by stirring the developer waste liquid side while the developer waste liquid stored in the development processing waste liquid tank is in contact with the air present in the automatic developing machine. By promoting the contact, carbon dioxide in the air can be efficiently removed. It is preferable to increase the contact area between air and the developer waste liquid by vigorously stirring the developer waste liquid side with a screw or the like while the developer waste liquid is in contact with the air present in the automatic developing machine. This agitation is more effective when the agitation is so strong that air is drawn into the developer waste liquid in the form of bubbles. In this method, since the liquid feed pump is not essential, it is possible to avoid problems such as clogging of the developer waste liquid component.
[0135]
2) The contact is promoted by bubbling the air present in the automatic developing machine into the developer waste liquid stored in the developer waste liquid tank. Specifically, air present in the automatic developing machine is bubbled into the developer waste liquid using an air pump to increase the contact area between the air and the developer waste liquid. In this case, since a liquid feed pump is not essential on the developer waste liquid side although an air pump is used, problems such as clogging of the developer waste liquid component can be avoided.
[0136]
3) By discharging the developer waste liquid stored in the development processing waste liquid tank in the air existing in the automatic developing machine or in the development processing tank storing the developer in the form of a mist with a spray nozzle or the like. Promote contact. In this case, the landing point on the dropped developer waste liquid side has an inclination or has a structure that absorbs the impact, so that the impact on the landing of the droplet is softened, and the problem of splashing and foaming is avoided. be able to. Moreover, efficient carbon dioxide gas removal can be performed by dripping mainly on the part into which air enters.
[0137]
In the above methods 1) and 2), when the air present in the developing vessel containing the developing solution is brought into contact with the developer waste solution outside the developing treatment vessel, the carbon dioxide gas is removed by contacting the developer waste solution. It is necessary to return the air to the development processing tank. In this case, the air from which the carbon dioxide gas has been removed is preferably returned to the vicinity of the developer surface.
[0138]
The present invention also relates to a method for reducing deterioration of a water-based alkaline developer containing substantially no silicate by carbon dioxide present in the air, when the photosensitive lithographic printing plate is not processed. It can also be applied to.
[0139]
There are basically four. The first is to reduce the carbon dioxide in the air present in the automatic processor by forcing the air present in the automatic processor to contact the developer waste liquid stored in the development waste tank. The second aspect of the invention is to force the air present in the development processing tank to contact the developer waste liquid stored in the development processing tank and then circulate the contacted air in the development processing tank. The carbon dioxide gas in the air present in the development processing tank is reduced (the invention according to claim 9), and the third is to send air decarbonized using the developer waste liquid into the development processing tank. (Invention of Claim 10), the fourth is to send the air degassed with developer waste liquid into the automatic developing machine (Invention of Claim 11).
[0140]
Carbon dioxide is usually contained in the atmosphere in an amount of 0.03 vol%, and it is preferable to reduce it to 1/2 or less, that is, 0.015 vol%. In an indoor environment, there are cases where the carbon dioxide concentration increases due to the influence of an oil stove or the like. The carbon dioxide gas concentration is preferably reduced to a concentration of ½ or less of the carbon dioxide gas contained in the indoor air where the automatic processor is located.
[0141]
The method described above can be adopted as a method for forcing air into the developer waste liquid stored in the development waste liquid tank. The time when carbon dioxide in the air in the automatic processor is reduced by forcibly bringing air into contact with the developer waste liquid stored in the developer waste liquid tank is the most suitable for processing the photosensitive lithographic printing plate. Of course, it may be good, but it may be when the photosensitive lithographic printing plate is not processed.
[0142]
In the invention described in claims 10 and 11, the air forcibly brought into contact with the developer waste liquid may be air in the vicinity of the outside of the automatic processor.
[0143]
Further, in the invention described in claim 9 and claim 10, it is preferable that the decarbonized gas is sent to the vicinity of the liquid level of the developer.
[0144]
<Processing after development>
The photosensitive lithographic printing plate thus developed is washed with water, surface active as described in JP-A Nos. 54-8002, 55-1115045 and 59-58431. It is post-treated with a desensitizing solution containing a rinse solution containing an agent and the like, gum arabic and starch derivatives. These treatments can be used in various combinations for the post-treatment of the photosensitive lithographic printing plate of the present invention. The printing plate obtained by the above treatment can be improved in printing durability by post-exposure treatment or heating treatment such as burning according to the method described in JP-A-2000-89478. The planographic printing plate obtained by such processing is loaded on an offset printing machine and used for printing a large number of sheets.
[0145]
【Example】
Although a synthesis example, a support body preparation example, and an example are specifically shown below, embodiments of the present invention are not limited thereto. In the examples, “parts” represents “parts by mass” unless otherwise specified.
[0146]
(Example 1)
<< Preparation of photosensitive lithographic printing plate >>
<Preparation of photosensitive lithographic printing plate 1>
On the following support, a photopolymerization type photosensitive layer coating solution 1 having the following composition was dried at 1.5 g / m.²Then, it was coated with a wire bar and dried at 95 ° C. for 1.5 minutes to obtain a photopolymerization type photosensitive layer coated sample.
[0147]
(Synthesis of polymer binder (acrylic copolymer 1))
A three-necked flask under a nitrogen stream is charged with 30 parts of methacrylic acid, 50 parts of methyl methacrylate, 20 parts of ethyl methacrylate, 500 parts of isopropyl alcohol and 3 parts of α, α'-azobisisobutyronitrile. The reaction was carried out for 6 hours in an oil bath at 0 ° C. Then, after refluxing for 1 hour at the boiling point of isopropyl alcohol, 3 parts of triethylammonium chloride and 25 parts of glycidyl methacrylate were added and reacted for 3 hours to obtain an acrylic copolymer 1. The weight average molecular weight measured using GPC was about 35,000, and the glass transition temperature (Tg) measured using DSC (differential thermal analysis) was about 85 ° C.
[0148]
(Production of support)
An aluminum plate (material 1050, tempered H16) having a thickness of 0.3 mm was immersed in a 5% aqueous sodium hydroxide solution maintained at 65 ° C., degreased for 1 minute, and then washed with water. This degreased aluminum plate was neutralized by immersion in a 10% aqueous hydrochloric acid solution maintained at 25 ° C. for 1 minute, and then washed with water. Next, the aluminum plate was placed in a 0.3% by mass nitric acid aqueous solution at 25 ° C. and a current density of 100 A / dm.²Electrolytic surface roughening was performed for 60 seconds with an alternating current under the above conditions, followed by desmutting treatment for 10 seconds in a 5% aqueous sodium hydroxide solution maintained at 60 ° C. The surface-roughened aluminum plate subjected to the desmut treatment was subjected to a current density of 10 A / dm at 25 ° C. in a 15% sulfuric acid solution.²Then, an anodizing treatment was performed for 1 minute under the condition of a voltage of 15 V, and a hydrophilization treatment was further performed with 1% polyvinylphosphonic acid at 75 ° C. to prepare a support.
[0149]
At this time, the center line average roughness (Ra) of the surface was 0.65 μm.
(Photopolymerization type photosensitive layer coating solution 1)

[0150]
[Chemical 6]

[0151]
On the photopolymerization type photosensitive layer coating sample, an oxygen barrier layer coating solution 1 having the following composition was dried at 1.8 g / m 2.²The photosensitive lithographic printing plate 1 having an oxygen blocking layer on the photosensitive layer was prepared by applying with an applicator so as to become, and drying at 75 ° C. for 1.5 minutes.
[0152]
(Oxygen barrier layer coating solution 1)
Polyvinyl alcohol (GL-05: Nippon Synthetic Chemical Co., Ltd.) 89 parts
10 parts of water-soluble polyamide (P-70: manufactured by Toray Industries, Inc.)
Surfactant (Surfinol 465: Nissin Chemical Industry Co., Ltd.) 0.5 part
900 parts of water
<Preparation of photosensitive lithographic printing plate 2>
Photosensitive lithographic printing except that the photopolymerization initiator was changed to I-3 (4.0 parts) and the spectral sensitizing dye was changed to D-3 (3.0 parts). A photosensitive lithographic printing plate 2 was produced in the same manner as the production of the plate 1.
[0153]
[Chemical 7]

[0154]
<Preparation of photosensitive lithographic printing plate 3>
Preparation of the photosensitive lithographic printing plate 1 except that the spectral sensitizing dye was changed to D-5 (1.5 parts) and D-7 (1.5 parts) in the photopolymerization type photosensitive layer coating solution 1. A photosensitive lithographic printing plate 3 was prepared in the same manner.
[0155]
[Chemical 8]

[0156]
《Developer formulation》

《Finisher formulation》
(Plate surface protectant (gum solution) 1L aqueous formulation)
White dextrin 5.0% by mass
Hydroxypropyl etherified starch 10.0% by mass
Gum arabic 1.0% by mass
1st Ammon Phosphate 0.1% by mass
Sodium dilauryl succinate 0.15% by mass
Polyoxyethylene naphthyl ether 0.5% by mass
Polyoxyethylene polyoxypropylene block copolymer
(Ethylene oxide ratio 50 mol%, molecular weight 5000) 0.3 mass%
Ethylene glycol 1.0% by mass
Ethylenediaminetetraacetic acid disodium 0.005 mass%
Ethylparaben 0.005 mass%
"exposure"
About photosensitive lithographic printing plates 1 and 2 produced as described above, a CTP exposure apparatus (Tigercat: manufactured by ECRM) equipped with an FD-YAG laser light source was used, and the number of dots per 2.54 cm was 2400 dpi. Image exposure (exposure pattern used 100% image area and 175 LPI 50% square dots). The photosensitive lithographic printing plate 3 was subjected to the same image exposure using a plate setter (Tiger Cat: modified product manufactured by ECRM) equipped with a laser of 408 nm and 30 mW output.
[0157]
Next, with the following CTP automatic developing machine, development is performed at 500 m so that the area ratio of the image area to the non-image area is 1: 9²Carried out. About 50ml / m²The developer was replenished so that
[0158]
<Development processing>
<Development processing 1> (Invention)
It includes a pre-rinsing part that removes the oxygen blocking layer before development, a developing part filled with a developing solution (developing treatment tank), a washing part that removes the developing solution adhering to the plate surface, and the above-mentioned gum solution for protecting the image area. The CTP automatic processor (PHW32-V: manufactured by Technigraph) was used to provide a 5L container (development waste liquid tank) with a lid for temporarily storing the overflow liquid obtained from the development waste liquid. Not filled with developer replenisher. The development running solution overflow solution (developer waste solution) was allowed to flow with the development process, and the portion that became 5 L or more was discarded, so that the change to the developer waste solution was gradually advanced. In this state, the air present in the space above the development processing tank is taken out with an air pump, and while flowing into the 5 L container (development processing waste liquid tank) with the lid, the air is extracted, and the air is developed. Returned to the cage. Further, the developer waste liquid in a 5 L container with a lid was stirred with a screw to promote contact between the developer waste liquid and air.
[0159]
<Development processing 2> (Invention)
It includes a pre-rinsing part that removes the oxygen blocking layer before development, a developing part filled with a developing solution (developing treatment tank), a washing part that removes the developing solution adhering to the plate surface, and the above-mentioned gum solution for protecting the image area. The CTP automatic processor (PHW32-V: manufactured by Technigraph) was used to provide a 5L container (development waste liquid tank) with a lid for temporarily storing the overflow liquid obtained from the development waste liquid. Not filled with developer replenisher. The development running solution overflow solution (developer waste solution) was allowed to flow with the development process, and the portion that became 5 L or more was discarded, so that the change to the developer waste solution was gradually advanced. In this state, the air present in the space above the development processing tank is taken out by an air pump, and the liquid level is bubbled from the bottom part of the development waste liquid in the 5 L container (development processing liquid tank) with the lid. The air rising from the air was extracted, and the air was returned into the development processing tank to promote contact between the developer waste liquid and air.
[0160]
<Development 3> (Invention)
It includes a pre-rinsing part that removes the oxygen blocking layer before development, a developing part filled with a developing solution (developing treatment tank), a washing part that removes the developing solution adhering to the plate surface, and the above-mentioned gum solution for protecting the image area. A CTP automatic processor (PHW32-V: manufactured by Technigraph) was used to provide a 5 L container (development waste liquid tank) with a lid to temporarily store the overflow liquid obtained from the development waste liquid. Not filled with developer replenisher. The development running solution overflow solution (developer waste solution) was allowed to flow with the development process, and the portion that became 5 L or more was discarded, so that the change to the developer waste solution was gradually advanced. This solution is repeatedly dropped in a shower-like manner so as to come into contact with the air between the development processing tank of the automatic processor and the developing unit lid with a liquid feed pump, and the dropped liquid is again a 5 L container with a lid (developing) By returning to the processing waste liquid soot), the contact between the developer waste liquid and air was promoted.
[0161]
<Development 4> (Comparative example)
CTP automatic developing machine equipped with a pre-rinsing part for removing the oxygen blocking layer before development, a developing part filled with a developer, a water washing part for removing the developer adhering to the plate surface, and the above-mentioned gum solution for protecting the image line part (PHW32-V: manufactured by Technigraph) was subjected to normal development without providing a development waste liquid tank.
[0162]
<Evaluation>
<Non-image area ink smear>
Each of the above photosensitive lithographic printing plates was developed by combining each developer, developer replenisher formulation, and each developing treatment as shown in Table 1 to prepare a lithographic printing plate. The produced lithographic printing plate was coated with a printing press (DAIYA1F-1 manufactured by Mitsubishi Heavy Industries, Ltd.), printing ink (soybean oil ink “Naturalis 100” manufactured by Dainippon Ink & Chemicals, Inc.) and dampening water. Printing was performed using (Tokyo ink Co., Ltd. H liquid SG-51 concentration 1.5%).
[0163]
500m²100 cm on the non-image area of the printed material after printing²The spotted ink stains inside were visually evaluated.
[0164]
A: Ink smear is not observed in the non-image area.
○: Ink smear is hardly observed in the non-image area.
[0165]
Δ: Slight ink stains are observed in the non-image area, but can be used as printed matter.
X: Ink stains are observed in the non-image area and cannot be used as printed matter.
[0166]
The evaluation results are shown in Table 1.
<Evaluation of sludge sludge>
The overflow waste liquid from the development processing waste liquid tank was sent out to a 5 L container with a lid installed outside the automatic processor by a liquid feed pump, and the occurrence state of sludge and sludge and the state of foaming were visually confirmed.
[0167]
◯: Slight sludge is slightly generated in the container, but it does not adhere to the lithographic printing plate to be developed and there is virtually no problem.
[0168]
Δ: Sludge and sludge are observed in the container, and the cleaning operation in the container requires rubbing with a sponge, a brush, or the like.
[0169]
X: Gel sludge sludge is generated in the container, the inside of the container is gelled, the fluidity is deteriorated, and problems occur in the liquid feed pump and the stirring screw.
[0170]
The evaluation results are shown in Table 1.
[0171]
[Table 1]

[0172]
From Table 1, it can be seen that the ink-stained ink according to the present invention hardly shows ink stains and is acceptable for the generation of sludge and sludge. That is, in the present invention, the developer does not contain any silicate (SiO 2₂(0.0% in terms of mass) is desirable, but the silicate is SiO₂It turns out that there is no problem if it is about 0.1% in terms of mass.
[0173]
(Example 2)
In Example 1, the photosensitive lithographic printing plate was developed in the same manner as in Example 1 except that the air present in the automatic processor was used instead of the air present in the space above the development processing tank. As in Example 1, the ink of the present invention showed almost no ink stains and was acceptable for sludge sludge generation.
[0174]
(Example 3)
In Example 1, a development waste liquid tank was provided in the vicinity of the outside of the automatic developing machine, and the development process was carried out while air decarbonized using the developer waste liquid was sent into the development treatment tank. According to the present invention, ink stains were hardly observed, and the generation of sludge and sludge was acceptable.
[0175]
Example 4
In Example 1, a development waste liquid tank was provided in the vicinity of the outside of the automatic processor, and the development process was carried out while air decarbonized using the developer waste liquid was sent into the automatic processor. The inks of the invention showed little ink stains and were acceptable for sludge sludge generation.
[0176]
(Example 5)
The same operation as in Examples 1 to 4 was performed until immediately before the development processing, and the decarbonized gas was sent into the automatic developing machine or the development processing tank to evaluate the deterioration of the developer. There was a significant difference in the reduction of developer deterioration compared to the developer left without being fed.
[0177]
【The invention's effect】
According to the present invention, the development stability of the developing solution is maintained, and problems such as an increase in cost and an increase in waste liquid due to an increase in the amount of replenishing solution are solved at the same time. It was possible to provide a photosensitive lithographic printing plate processing method and a developer deterioration reducing method in which sludge generation was suppressed.

Claims (15)

After exposure, a photopolymerizable photosensitive lithographic printing plate provided with a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder on a support, In a processing method of a photosensitive lithographic printing plate for developing with an automatic processor having a developing processing tub that stores a developing solution and a developing processing effluent that discharges the developing solution waste discharged from the developing processing tub, the developing solution is The aqueous alkaline developer containing substantially no silicate, and developing while forcibly bringing the air present in the automatic developing machine into contact with the developer waste liquid stored in the developer waste tank. A method for processing a photosensitive lithographic printing plate characterized by After exposure, a photopolymerizable photosensitive lithographic printing plate provided with a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder on a support, In a processing method of a photosensitive lithographic printing plate for developing with an automatic processor having a developing processing tub that stores a developing solution and a developing processing effluent that discharges the developing solution waste discharged from the developing processing tub, the developing solution is A water-based alkaline developer containing substantially no silicate, and the air present in the development processing tank is forcibly brought into contact with the developer waste liquid stored in the development processing liquid tank, and then contacted. A method for processing a photosensitive lithographic printing plate, wherein the development processing is performed while circulating air in the development processing tank. After exposure, a photopolymerization type photosensitive lithographic printing plate provided with a photopolymerization type photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder on a support, In a processing method of a photosensitive lithographic printing plate for developing with an automatic processor having a developing processing tub that stores a developing solution and a developing processing effluent that discharges the developing solution waste discharged from the developing processing tub, the developing solution is A photosensitive lithographic plate, which is a water-based alkaline developer substantially free of silicate, and is developed while being fed with carbon dioxide-degassed air using the developer waste solution into the developing treatment tank. Processing method for printing plates. After exposure, a photopolymerizable photosensitive lithographic printing plate provided with a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder on a support, In a processing method of a photosensitive lithographic printing plate for developing with an automatic processor having a developing processing tub that stores a developing solution and a developing processing effluent that discharges the developing solution waste discharged from the developing processing tub, the developing solution is Photosensitive lithographic printing, which is a water-based alkaline developer substantially free of silicate, and is developed while sending air decarbonized using the developer waste solution into the automatic processor. Plate processing method. 5. The method for processing a photosensitive lithographic printing plate according to claim 1, wherein the developer further contains a surfactant having a polyoxyalkylene group. The photosensitive agent according to claim 5, wherein the surfactant having a polyoxyalkylene group is a nonionic surfactant having a molecular weight of 0 to 25% of a saturated alkyl moiety in the entire hydrophobic group. Processing method for lithographic printing plates. The photosensitive lithographic plate according to claim 5, wherein the surfactant having a polyoxyalkylene group is an anionic surfactant having a molecular weight of 0 to 25% of a saturated alkyl moiety in the entire hydrophobic group. Processing method for printing plates. After exposure, a photopolymerizable photosensitive lithographic printing plate provided with a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder on a support, In the method for reducing deterioration of a developer for developing with an automatic processor having a developing treatment tank containing the developing solution and a developing treatment waste liquid discharged from the developing treatment basket, the developer is A water-based alkaline developer substantially free of silicate, and the air present in the automatic processor is forcibly brought into contact with the developer waste liquid stored in the development processing waste tank. A method for reducing deterioration of a developing solution, comprising reducing carbon dioxide gas in the air present in the developer. After exposure, a photopolymerizable photosensitive lithographic printing plate provided with a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder on a support, In the method for reducing deterioration of a developer for developing with an automatic processor having a developing treatment tank containing the developing solution and a developing treatment waste liquid discharged from the developing treatment basket, the developer is A water-based alkaline developer containing substantially no silicate, and the air present in the development processing tank is forcibly brought into contact with the developer waste liquid stored in the development processing liquid tank, and then contacted. A method for reducing deterioration of a developing solution, characterized in that carbon dioxide gas in the air existing in the development processing tank is reduced by circulating air in the development processing tank. After exposure, a photopolymerizable photosensitive lithographic printing plate provided with a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder on a support, In the method for reducing deterioration of a developer for developing with an automatic processor having a developing treatment tank containing the developing solution and a developing treatment waste liquid discharged from the developing treatment basket, the developer is A method for reducing deterioration of a developing solution, which is a water-based alkaline developer containing substantially no silicate, and wherein air degassed with the developer waste solution is sent into the developing treatment tank. After exposure, a photopolymerizable photosensitive lithographic printing plate provided with a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated bond capable of addition polymerization, a photopolymerization initiator and a polymer binder on a support, In the method for reducing deterioration of a developer for developing with an automatic processor having a developing treatment tank containing the developing solution and a developing treatment waste liquid discharged from the developing treatment basket, the developer is A method for reducing deterioration of a developer, which is a water-based alkaline developer containing substantially no silicate and degassed gas using the developer waste solution is fed into the automatic processor. The method for reducing deterioration of a developer according to any one of claims 8 to 11, wherein the developer contains a surfactant having a polyoxyalkylene group. 13. The developer according to claim 12, wherein the surfactant having a polyoxyalkylene group is a nonionic surfactant having a molecular weight of 0 to 25% of a saturated alkyl moiety in the entire hydrophobic group. Degradation reduction method. 13. The developer according to claim 12, wherein the surfactant having a polyoxyalkylene group is an anionic surfactant having a molecular weight of 0 to 25% of a saturated alkyl moiety in the entire hydrophobic group. Degradation reduction method. The development is carried out by replacing the air forcedly brought into contact with the aqueous alkaline developer waste solution substantially free of silicate with the air in the development processing tank containing the aqueous alkaline developer substantially free of silicate. A method to reduce liquid degradation.