JP3761478B2 - Lithographic printing plate support and lithographic printing plate precursor - Google Patents

Description

【０３０９】
（ｊ）感熱層の形成
ついで、下記組成の感熱層塗布液１を調製し、下塗りしたアルミニウム支持体に、この感熱層塗布液１を乾燥後の塗布量（感熱層塗布量）が１．０ｇ／ｍ² になるよう塗布し、乾燥して感熱層（サーマルポジタイプの画像記録層）を形成させ、実施例１の平版印刷版原版を得た。
【０３１０】
＜感熱層塗布液１組成＞
・カプリン酸 ０．０３ｇ
・後述する特定の共重合体１ ０．７５ｇ
・ｍ，ｐ−クレゾールノボラック（ｍ／ｐ比＝６／４、重量平均分子量３，５００、未反応クレゾール０．５質量％含有） ０．２５ｇ
・ｐ−トルエンスルホン酸 ０．００３ｇ
・テトラヒドロ無水フタル酸 ０．０３ ｇ
・下記式で表されるシアニン染料Ａ ０．０１７ｇ
【０３１１】
【化２】

【０３１２】
・ビクトリアピュアブルーＢＯＨの対イオンを１−ナフタレンスルホン酸アニオンにした染料 ０．０１５ｇ
・フッ素系界面活性剤（メガファックＦ−１７７、大日本インキ化学工業社製） ０．０５ｇ
・γ−ブチルラクトン １０ｇ
・メチルエチルケトン １０ｇ
・１−メトキシ−２−プロパノール １ｇ
【０３１３】
＜特定の共重合体１＞
かくはん機、冷却管および滴下ロートを備えた５００ｍＬ容の三つ口フラスコに、メタクリル酸３１．０ｇ（０．３６ｍｏｌ）、クロロギ酸エチル３９．ｌｇ（０．３６ｍｏｌ）およびアセトニトリル２００ｍＬを入れ、氷水浴で冷却しながら混合物をかくはんした。この混合物にトリエチルアミン３６．４ｇ（０．３６ｍｏｌ）を約１時間かけて滴下ロートにより滴下した。滴下終了後、氷水浴を取り去り、室温下で３０分間混合物をかくはんした。
【０３１４】
この反応混合物に、ｐ−アミノベンゼンスルホンアミド５１．７ｇ（０．３０ｍｏｌ）を加え、油浴にて７０℃に温めながら混合物を１時間かくはんした。反応終了後、この混合物を水１Ｌにこの水をかくはんしながら投入し、３０分間得られた混合物をかくはんした。この混合物をろ過して析出物を取り出し、これを水５００ｍＬでスラリーにした後、このスラリーをろ過し、得られた固体を乾燥することによりＮ−（ｐ−アミノスルホニルフェニル）メタクリルアミドの白色固体が得られた（収量４６．９ｇ）。
【０３１５】
つぎに、かくはん機、冷却管および滴下ロートを備えた２０ｍＬ容の三つ口フラスコに、Ｎ−（ｐ−アミノスルホニルフェニル）メタクリルアミド４．６１ｇ（０．０１９２ｍｏｌ）、メタクリル酸エチル２．９４ｇ（０．０２５８ｍｏｌ）、アクリロニトリル０．８０ｇ（０．０１５ｍｏｌ）およびＮ，Ｎ−ジメチルアセトアミド２０ｇを入れ、湯水浴により６５℃に加熱しながら混合物をかくはんした。この混合物に「Ｖ−６５」（和光純薬社製）０．１５ｇを加え、６５℃に保ちながら窒素気流下で、混合物を２時間かくはんした。この反応混合物に更にＮ−（ｐ−アミノスルホニルフェニル）メタクリルアミド４．６１ｇ、メタクリル酸エチル２．９４ｇ、アクリロニトリル０．８０ｇ、Ｎ，Ｎ−ジメチルアセトアミドおよび「Ｖ−６５」０．１５ｇの混合物を２時間かけて滴下ロートにより滴下した。滴下終了後、更に、得られた混合物を６５℃で２時間かくはんした。反応終了後、メタノール４０ｇを混合物に加え、冷却し、得られた混合物を水２Ｌにこの水をかくはんしながら投入し、３０分混合物をかくはんした後、析出物をろ過により取り出し、乾燥することにより１５ｇの白色固体の特定の共重合体１を得た。
得られた特定の共重合体１の重量平均分子量をゲルパーミエーションクロマトグラフィーにより測定したところ、５３，０００（ポリスチレン標準）であった。
【０３１６】
（実施例２）
上記（ｇ）陽極酸化処理において、電解液として、４質量％のホウ酸アンモニウム水溶液を用い、第一電解部６３ａおよび第二電解部６３ｂにおける電流密度をともに０．１Ａ／ｄｍ² として低電流電解とした以外は、実施例１と同様の方法により、実施例２の平版印刷版原版を得た。
【０３１７】
（実施例３）
上記（ｄ）電気化学的粗面化処理において、電解液を塩酸７．５ｇ／Ｌ水溶液（アルミニウムイオンを５ｇ／Ｌ含む。）とし、電流密度を電流のピーク値で２５Ａ／ｄｍ² とし、電気量をアルミニウム板が陽極時の電気量の総和で５０Ｃ／ｄｍ² とした以外は、実施例１と同様の方法により、実施例３の平版印刷版原版を得た。
【０３１８】
（実施例４）
用いたアルミニウム板におけるＣｕ含有量を０．０１７質量％とした以外は、実施例１と同様の方法により、実施例４の平版印刷版原版を得た。
【０３１９】
（実施例５）
（ｇ）陽極酸化処理後、（ｈ）アルカリ金属ケイ酸塩処理前に、下記のようにして加圧水蒸気を用いて封孔処理を行った以外は、実施例１と同様の方法により、実施例５の平版印刷版原版を得た。
封孔処理は、１００℃、１気圧において飽和した蒸気チャンバーの中で１０秒間処理することにより行った。
【０３２０】
（実施例６）
上記（ｄ）電気化学的粗面化処理において、電解液として、硝酸１０ｇ／Ｌ水溶液（アルミニウムイオンを５ｇ／Ｌ、アンモニウムイオンを０．００７質量％含む。）を用い、電解液の温度を８０℃とし、ＴＰを０ｍｓｅｃとし、電気量をアルミニウム板が陽極時の電気量の総和で１３０Ｃ／ｄｍ² とした以外は、実施例１と同様の方法により、実施例６の平版印刷版原版を得た。
【０３２１】
（比較例１）
上記（ａ）機械的粗面化処理を行わなかった以外は、実施例１と同様の方法により、比較例１の平版印刷版原版を得た。
【０３２２】
（比較例２）
上記（ｄ）電気化学的粗面化処理において、用いた交流電圧の周波数を３Ｈｚとし、電解液の温度を３５℃とし、電気量をアルミニウム板が陽極時の電気量の総和で４００Ｃ／ｄｍ² とした以外は、実施例１と同様の方法により、比較例２の平版印刷版原版を得た。
【０３２３】
（比較例３）
上記（ｇ）陽極酸化処理において、電解液の硫酸濃度を２５０ｇ／Ｌ（アルミニウムイオンを０．５質量％含む。）とし、電解液の温度を５０℃とした以外は、実施例１と同様の方法により、比較例３の平版印刷版原版を得た。
【０３２４】
（比較例４）
上記（ｇ）陽極酸化処理において、電解液として、５０ｇ／Ｌのリン酸水溶液を用い、第一電解部６３ａおよび第二電解部６３ｂにおける電流密度をともに２０Ａ／ｄｍ² とした以外は、実施例１と同様の方法により、比較例４の平版印刷版原版を得た。
【０３２５】
（比較例５）
上記（ｅ）アルカリエッチング処理において、液温を調整してアルミニウム板の溶解量を１．０ｇ／ｍ² とした以外は、実施例１と同様の方法により、比較例５の平版印刷版原版を得た。
【０３２６】
２．平版印刷版用支持体のピット（中波構造）の平均直径の測定およびピット内部の微細な凹凸（小波構造）の観察
平版印刷版用支持体の表面を、支持体に垂直な方向から、走査型電子顕微鏡（ＳＥＭ）を用いて倍率１００００倍のＳＥＭ写真を撮影した。ＳＥＭ写真において、３０個のピットについて直径を測定し、ピットの平均直径を求めた。また、ＳＥＭ写真において、ピット内部に微細な凹凸があるか否かを観察した。
結果を第１表に示す。
【０３２７】
３．平版印刷版用支持体の表面の大波構造の波長の測定
平版印刷版原版の感熱層をγ−ブチロラクトンで溶解除去した後、日本電子社製のＴ−２０型走査型電子顕微鏡を用いて、法線方向から３０℃の方向から、露出した表面を倍率２０００倍で観察し、２μｍより大きい波長成分を水平方向に３０点測定して、その平均波長を求めた。
結果を第１表に示す。なお、第１表中、「−」は、該当する波長の凹部がなかったことを示す。
【０３２８】
４．マイクロポアの平均ポア径および平均ポア密度の測定
平版印刷版原版の感熱層をγ−ブチルラクトンで溶解除去し、更に、γ−ブチルラクトン中で３０分間超音波洗浄した後、露出した表面をＦＥ−ＳＥＭ（Ｓ−９００、日立製作所社製）により蒸着せずに倍率１５万倍でＳＥＭ写真を撮影した。ＳＥＭ写真で３視野観察し、１００個のポアについてポア径を測定し、その平均値を平均ポア径とした。
また、前記ＳＥＭ写真から、３００ｎｍ四方の部分を３視野抜き取り、その中のポア数を数えてポア密度の平均値を求め、平均ポア密度とした。
結果を第１表に示す。
【０３２９】
５．平版印刷版原版の傷付きにくさの評価
上記のようにして得られた平版印刷版原版について、傷付きにくさの評価を行った。
平版印刷版原版の感熱層表面に合紙を置き、その上下を段ボール紙で挟み、２５℃、５０％ＲＨの環境下で３日間放置した。その後、平版印刷版原版の感熱層表面を木綿製の手袋で５往復擦り、富士写真フイルム（株）製のＰＳ版用現像液ＤＴ−１を標準使用条件で用いて、自動現像機９００ＮＰにより現像した。擦った部分が傷付いて白く抜けている程度を目視で観察して評価した。
現像前と全く変化なかったものを○、ほぼ支持体が見えてしまい感熱層の色がほとんど見えなかったものを×、その中間レベルを○△、△、△×で表した。
結果を第１表に示す。
【０３３０】
６．平版印刷版原版の感度の評価
平版印刷版原版をＣＲＥＯ社製のＴｒｅｎｄＳｅｔｔｅｒ３２４４を用いて版面エネルギー量を変更して全面露光した後、富士写真フイルム（株）製のＰＳ版用現像液ＤＴ−１を標準使用条件で用いて、自動現像機９００ＮＰにより現像した。感熱層が完全に除去されたと目視で観察されたときの版面エネルギー量により感度を評価した。
結果を第１表に示す。
【０３３１】
７．平版印刷版原版の耐汚れ性の評価
平版印刷版原版を出力５００ｍＷ、波長８３０ｎｍビーム径１７μｍ（１／ｅ² ）の半導体レーザーを装備したＣＲＥＯ社製ＴｒｅｎｎｄＳｅｔｔｅｒ３２４４を用いて主走査速度５ｍ／秒、版面エネルギー量１４０ｍＪ／ｃｍ² で像様露光した。
その後、非還元糖と塩基とを組み合わせたＤ−ソルビット／酸化カリウムＫ₂ Ｏよりなるカリウム塩５．０質量％およびオルフィンＡＫ−０２（日信化学社製）０．０１５質量％を含有する水溶液１ＬにＣ₁₂Ｈ₂₅Ｎ（ＣＨ₂ ＣＨ₂ ＣＯＯＮａ）₂ を１ｇ添加したアルカリ現像液を用いて現像処理を行った。現像処理は、上記アルカリ現像液を満たした自動現像機ＰＳ９００ＮＰ（富士写真フイルム（株）製）を用いて、現像温度２５℃、１２秒の条件で行った。現像処理が終了した後、水洗工程を経て、ガム（ＧＵ−７（１：１））等で処理して、製版が完了した平版印刷版を得た。
このようにして得られた平版印刷版を用いて、三菱ダイヤ型Ｆ２印刷機（三菱重工業社製）で、ＤＩＣ−ＧＥＯＳ（ｓ）紅のインキを用いて印刷し、１万枚印刷した後におけるブランケットの汚れを目視で評価した。
【０３３２】
８．平版印刷版原版の耐刷性の評価
耐汚れ性の評価と同様の方法で得られた平版印刷版を用いて、小森コーポレーション社製のリスロン印刷機で、大日本インキ化学工業社製のＤＩＣ−ＧＥＯＳ（Ｎ）墨のインキを用いて印刷し、ベタ画像の濃度が薄くなり始めたと目視で認められた時点の印刷枚数により、耐刷性を評価した。
【０３３３】
本発明の平版印刷版用支持体を用いた本発明の平版印刷版原版は、傷付きにくく、かつ、感度に優れることが分かる（実施例１〜６）。特に、用いたアルミニウム板におけるＣｕ含有量が０．００５質量％である場合（実施例１〜３、５および６）は、中波構造を構成するピットの平均直径が小さく均一になりやすく、特に傷付きにくい。
これに対して、比較例１〜５は、実施例１〜６と同様に、感熱層表面の凹凸を少なくして滑らかにしたものであるが、以下のような欠点がある。即ち、平版印刷版用支持体の表面に大波構造がない場合（比較例１）および大波構造の波長が長すぎる場合（比較例２）は、感熱層と支持体との間ではく離を起こし、傷付きやすい。また、陽極酸化皮膜のマイクロポアの平均ポア密度が高すぎる場合（比較例３）および平均ポア径が大きすぎる場合（比較例４）は、感度に劣る。更に、ピット内部に微細な凹凸を有しない場合（比較例５）は、感熱層と支持体との間ではく離を起こし、傷付きやすい。
また、本発明の平版印刷版用支持体を用いた本発明の平版印刷版原版は、比較例１〜５の平版印刷版原版に比べて、耐汚れ性および耐刷性にも優れていた。
【０３３４】
【表１】

【０３３５】
＜サーマルネガタイプの平版印刷版原版についての実施例＞
１．平版印刷版原版の作成
（実施例７〜１２および比較例６）
上記（ｈ）、（ｉ）および（ｊ）を行わず、下記（ｋ）、（ｌ）および（ｍ）を行った以外は、実施例１〜６および比較例５と同様の方法により、各平版印刷版原版を得た。
【０３３６】
（ｋ）アルカリ金属ケイ酸塩処理
陽極酸化処理により得られた各アルミニウム支持体（本発明の平版印刷版用支持体）を温度２５℃のケイ酸ソーダの２質量％水溶液の処理層中へ、１５秒間、浸せきすることでアルカリ金属ケイ酸塩処理（シリケート処理）を行った。その後、スプレーによる水洗を行った。
【０３３７】
（ｌ）中間層（下塗り層）の形成
上記のようにして得られたアルカリ金属ケイ酸塩処理後のアルミニウム支持体（本発明の平版印刷版用支持体）上に、後述する下塗り液を塗布し、支持体上のＳｉ量が３ｍｇ／ｍ² となるように塗設した。
【０３３８】
下塗り液は、以下のようにして調製した。
まず、下記の各化合物を混合し、かくはんした。約５分で発熱が認められた。６０分間反応させた後、内容物を別の容器へ移し、メタノール３０００ｇを加えることにより、ＳＧ法の液状組成物（ゾル液）を得た。得られたゾル液をメタノール／エチレングリコール＝９／１（質量比）で希釈して、下塗り液を得た。
【０３３９】
＜ゾル液組成＞
・メタノール １３０ｇ
・水 ２０ｇ
・８５質量％リン酸 １６ｇ
・テトラエトキシシラン ５０ｇ
・３−メタクリロキシプロピルトリメトキシシラン ６０ｇ
【０３４０】
（ｍ）感熱層の形成
ついで、中間層を設けた各アルミニウム支持体に、下記組成の感熱層塗布液［ＮＬ−１］をワイヤーバーを用いて、乾燥後の塗布量（感熱層塗布量）が１．３ｇ／ｍ² となるように塗布し、１１５℃で４５秒間乾燥させて、感熱層（サーマルネガタイプの画像記録層）を形成させ、平版印刷版原版［Ｎ−１］を得た。
【０３４１】
＜感熱層塗布液［ＮＬ−１］組成＞
・下記式で表される赤外線吸収剤 ０．１０ｇ
・下記式で表される重合開始剤（ラジカル発生剤） ０．３０ｇ
・ジペンタエリスリトールヘキサアクリレート １．００ｇ
・アリルメタクリレートとメタクリル酸との共重合体（モル比８０：２０、重量平均分子量１２万） １．００ｇ
・ビクトリアピュアブルーのナフタレンスルホン酸塩 ０．０４ｇ
・フッ素系界面活性剤（メガファックＦ−１７６、大日本インキ化学工業社製） ０．０１ｇ
・メチルエチルケトン ９．０ｇ
・メタノール １０．０ｇ
・１−メトキシ−２−プロパノール ８．０ｇ
【０３４２】
【化３】

【０３４３】
（実施例１３〜１８および比較例７）
上記（ｍ）において、感熱層塗布液［ＮＬ−１］の変わりに、下記組成の感熱層塗布液［ＮＬ−２］を用いた以外は、実施例７〜１２および比較例６と同様の方法により、平版印刷版原版［ＮＬ−２］を得た。
【０３４４】
＜感熱層塗布液［ＮＬ−２］組成＞
・上記［ＮＬ−１］で用いた赤外線吸収剤 ０．１０ｇ
・下記式で表される酸発生剤（Ｘ） ０．１５ｇ
・フェノールとホルムアルデヒドとから得られるノボラック樹脂（重量平均分子量１００００） １．５ｇ
・下記式で表される架橋剤ＭＭ−１ ０．５０ｇ
・フッ素系界面活性剤（メガファックＦ−１７７、大日本インキ化学工業社製） ０．０３ｇ
・メチルエチルケトン １５ｇ
・１−メトキシ−２−プロパノール １０ｇ
・メタノール ５ｇ
【０３４５】
【化４】

【０３４６】
２．平版印刷版原版の傷付きにくさの評価
上述したようにして各支持体から得られた平版印刷版原版［Ｎ−１］および［Ｎ−２］について、傷付きにくさの評価を行った。
平版印刷版原版の感熱層表面に合紙を置き、その上下を段ボール紙で挟み、２５℃、５０％ＲＨの環境下で３日間放置した。その後、平版印刷版原版の感熱層表面を木綿製の手袋で５往復擦り、後述する耐汚れ性および耐刷性の評価と同様の方法で、露光および現像処理を行って画像形成した。擦った部分が傷付いて白く抜けている程度を目視で観察して評価した。
【０３４７】
３．平版印刷版原版の感度の評価
上述したようにして各支持体から得られた平版印刷版原版［Ｎ−１］および［Ｎ−２］を、版面エネルギー量を変化させて露光した以外は、後述する耐汚れ性および耐刷性の評価と同様の方法で、露光および現像処理を行った。画像を形成することができた版面エネルギー量により感度を評価した。
【０３４８】
４．平版印刷版原版の耐汚れ性および耐刷性の評価
上述したようにして各支持体から得られた平版印刷版原版［Ｎ−１］および［Ｎ−２］を、版材供給装置（ＳＡ−Ｌ８０００）、露光装置（Ｌｕｘｅｌ Ｔ−９０００ＣＴＰ）、コンベア（Ｔ−９０００ Ｃｏｎｖｅｙｏｒ）、自動現像機（ＬＰ−１３１０Ｈ）およびストッカー（ＳＴ−１１６０）を具備する富士写真フイルム（株）製のＣＴＰ出力システムを用いて露光および現像処理を行って画像形成し、平版印刷版を得た。ここで、自動現像機の現像処理槽の第一浴には、ケイ酸アルカリを主成分とする現像液（富士写真フイルム（株）製ＤＰ−４の水希釈液（１：７））を仕込み、３０℃に保温した。第二浴には、水道水を仕込んだ。第三浴には、フィニッシングガム液（富士写真フイルム（株）製ＦＰ−２Ｗの水希釈液（１：１）を仕込んだ。
得られた平版印刷版を用いて、サーマルポジタイプの平版印刷版原版についての実施例と同様の方法で、印刷し、耐汚れ性および耐刷性の評価を行った。
【０３４９】
本発明の平版印刷版用支持体を用いた本発明の平版印刷版原版（実施例７〜１８）は、比較例６および７の平版印刷版原版に比べて、傷付きにくく、かつ、感度に優れていた。
また、実施例７〜１８の平版印刷版原版［Ｎ−１］および［Ｎ−２］は、いずれも耐汚れ性が良好であり、かつ、耐刷性が５万枚以上と優れていた。これは、サーマルネガタイプの平版印刷版原版においては、加熱または放射線の照射により画像記録層が硬化して画像部となるが、この際に、支持体の表面形状が本発明の平版印刷版用支持体のような特定の表面形状であると、画像記録層と支持体との密着性が高くなり、耐刷性が優れたものになるからであると考えられる。
【０３５０】
＜無処理タイプの平版印刷版原版についての実施例＞
１．平版印刷版原版の作成
上記（ｈ）、（ｉ）および（ｊ）を行わず、下記（ｎ）を行った以外は、実施例１〜６と同様の方法により、平版印刷版原版を得た。
【０３５１】
（ｎ）感熱層の形成
陽極酸化処理により得られた各アルミニウム支持体（本発明の平版印刷版用支持体）に、下記組成の感熱層用塗布液［ＭＬ］を乾燥後の塗布量（感熱層塗布量）が０．８ｇ／ｍ² になるようワイヤーバーで塗布し、９０℃で２分間乾燥させて、感熱層（無処理タイプの画像記録層）を形成させ、平版印刷版原版を得た。
【０３５２】
＜感熱層用塗布液［ＭＬ］組成＞
・水 ７０ｇ
・後述する合成例（１）で得られた、熱で外壁が破れるマイクロカプセル ５ｇ（固形分換算）
・ポリヒドロキシエチルアクリレート ０．５ｇ
・ｐ−ジアゾジフェニルアミン硫酸塩 ０．３ｇ
・下記式Ｆ１で表されるε−フタロシアニン（赤外線吸収剤）の分散物 ０．３ｇ
【０３５３】
【化５】

【０３５４】
＜合成例（１）＞
油相成分として、キシリレンジイソシアネート４０ｇ、トリメチロールプロパンジアクリレート１０ｇ、アリルメタクリレートとブチルメタクリレートとの共重合体（モル比６０／４０）１０ｇおよびパイオニンＡ４１Ｃ（竹本油脂社製）１０ｇを酢酸エチル６０ｇに溶解した。水相成分として、ＰＶＡ２０５（クラレ（株）製）の４％水溶液１２０ｇを調製した。油相成分と水相成分とをホモジナイザーを用いて１００００ｒｐｍで乳化した。その後、水を４０ｇ添加し、室温で３０分、更に４０℃で３時間かくはんした。このようにして得られたマイクロカプセル分散液の固形分濃度は２０質量％であり、マイクロカプセルの平均粒径は０．５μｍであった。
【０３５５】
２．平版印刷版原版の耐汚れ性および耐刷性の評価
上述したようにして各支持体から得られた平版印刷版原版を、水冷式４０Ｗ赤外線半導体レーザを搭載したＣｒｅｏ社製Ｔｒｅｎｄｓｅｔｔｅｒ ３２４４ＶＦＳを用いて、出力９Ｗ、外面ドラム回転数２１０ｒｐｍ、版面エネルギー１００ｍＪ／ｃｍ² 、解像度２４００ｄｐｉの条件で露光した後、何ら処理することなく、ハイデルベルグ社製印刷機ＳＯＲ−Ｍのシリンダーに取り付け、湿し水を供給した後、インキを供給し、更に紙を供給して印刷を行った。
各平版印刷版原版について、このようにして、問題なく機上現像をすることができ、印刷することができた。印刷１０枚目の印刷物を２０倍のルーペを用いて評価したところ、地汚れはなく、ベタ画像部の濃度の均一性は極めて良好であった。更に印刷を継続したところ、細線や細文字の欠落およびベタ画像濃度のムラはなく、非画像部の汚れも発生せず、良好な印刷物が２万枚以上得られた。
これは、無処理タイプのネガ型の平版印刷版原版においては、加熱または放射線の照射により画像記録層の有するマイクロカプセルが破れて内包物が流出した後に硬化するなどの機構で画像部となるが、この際に、支持体の表面形状が本発明の平版印刷版用支持体のような特定の表面形状であると、流出した内包物等が支持体表面の微細な凹凸にひっかかった状態で硬化し、画像記録層と支持体との密着性が高くなり、耐刷性が優れたものになるからであると考えられる。
【０３５６】
【発明の効果】
本発明の平版印刷版原版は、耐汚れ性および耐刷性に優れ、好ましくは、更に、傷付きにくく、感度が高く、印刷性能に優れ、通常作業での取り扱いが容易である。本発明の平版印刷版用支持体は、本発明の平版印刷版原版に好適に用いられる。
【図面の簡単な説明】
【図１】 本発明の平版印刷版用支持体の作成における機械粗面化処理に用いられるブラシグレイニングの工程の概念を示す側面図である。
【図２】 本発明の平版印刷版用支持体の作成における電気化学的な粗面化処理に用いられる交番波形電流波形図の一例を示すグラフである。
【図３】 本発明の平版印刷版用支持体の作成における電気化学的な粗面化処理に用いられる二つ以上のラジアルドラムローラを連結した装置の概略構成図である。
【図４】 本発明の平版印刷版用支持体の作成における陽極酸化処理に用いられる二段給電電解法の陽極酸化処理装置の概略図である。
【符号の説明】
１ アルミニウム板
２、４ ローラ状ブラシ
３ 研磨スラリー液
５、６、７、８ 支持ローラ
１１ アルミニウム板
１２ ラジアルドラムローラ
１３ａ、１３ｂ 主極
１４ 電解処理液
１５ 電解液供給口
１６ スリット
１７ 電解液通路
１８ 補助陽極
１９ａ、１９ｂ サイリスタ
２０ 交流電源
４０、４１ 主電解槽
５０、５１ 補助陽極槽
６２ａ 第一給電部
６２ｂ 第二給電部
６３ａ 第一電解部
６３ｂ 第二電解部
６４ａ、６４ｂ ニップローラ
６５ａ 第一給電電極
６５ｂ 第二給電電極
６６ａ、６６ｂ、６６ｃ、６６ｄ 電解電極
６７ａ、６７ｂ、６７ｃ、６７ｄ 電源[0001]
BACKGROUND OF THE INVENTION
  The present inventionPlanographic printing plate precursorSpecifically, when a lithographic printing plate is used, the support for a lithographic printing plate having an optimum surface shape capable of achieving both stain resistance and printing durabilityBodyIt relates to the lithographic printing plate precursor used. In addition, the present invention is excellent in stain resistance and printing durability, and also has excellent scratch resistance and sensitivity.BodyIt relates to the lithographic printing plate precursor used.
[0002]
[Prior art]
The lithographic printing method is a printing method that utilizes the fact that water and oil are not essentially mixed. The printing plate surface of the lithographic printing plate used for this is a region that accepts water and repels oil-based ink (hereinafter referred to as “removal”). This region is referred to as a “non-image portion”) and a region that repels water and receives oil-based ink (hereinafter, this region is referred to as “image portion”).
[0003]
An aluminum support for a lithographic printing plate used for a lithographic printing plate (hereinafter simply referred to as a “support for a lithographic printing plate”) is used so that its surface bears a non-image portion, and therefore has hydrophilicity and water retention. Are required to have various performances which are contradictory to each other, for example, excellent adhesion, and excellent adhesion to an image recording layer provided thereon.
If the hydrophilicity of the support is too low, ink will adhere to the non-image area during printing, and the blanket cylinder will be soiled, and so-called background soiling will occur. On the other hand, if the water holding capacity of the support is too low, the shadow portion is clogged unless dampening water is increased during printing. Therefore, the so-called water width is narrowed.
[0004]
In order to obtain a lithographic printing plate support having good performance, it is common to make the surface of an aluminum plate grained (roughening treatment) to give irregularities. Various shapes have been proposed for the unevenness as described below. JP-A-8-300844 describes a triple structure having a large wave, a medium wave, and a small wave that define the opening diameters of the medium wave and the small wave. Japanese Patent Application Laid-Open No. 11-99758 and Japanese Patent Application Laid-Open No. 11-208138 describe that the diameter of a small wave is defined in a large and small double structure. Japanese Patent Application Laid-Open No. 11-167207 describes a technique for providing further minute protrusions in addition to large and small double recesses (pits). Japanese Patent No. 2023476 describes a double structure that defines an opening diameter. JP-A-8-300843 describes a double structure that defines a factor a30 indicating the smoothness of the surface. Japanese Patent Application Laid-Open No. 10-35133 describes a structure that defines a ratio of pit diameters to be overlapped during a plurality of electrochemical surface roughening treatments (hereinafter also referred to as “electrolytic surface roughening treatment”).
[0005]
This graining includes mechanical graining methods such as ball graining, brush graining, wire graining, and blast graining, and an electrolytic grained surface for electrolytic etching of an aluminum plate in an electrolyte containing hydrochloric acid and / or nitric acid. And a composite surface roughening method combining a mechanical surface roughening method and an electrolytic surface roughening method described in US Pat. No. 4,476,006 are used.
[0006]
[Problems to be solved by the invention]
  However, in the above prior art, the stain resistance and the printing durability are in a trade-off relationship, and it is impossible to achieve both the stain resistance and the printing durability.
  Therefore, the present invention solves this problem and provides a planographic printing plate precursor that can achieve both excellent stain resistance and high printing durability.EditionThe purpose is to provide.
[0007]
In recent years, with the development of image forming technology, a laser beam with a narrow beam is scanned on the plate surface to form a character document, an image document, etc. directly on the plate surface, and directly plate-making without using a film document. Is becoming possible.
In the so-called thermal positive type lithographic printing plate precursor, which causes photo-thermal conversion in the image recording layer by laser light irradiation to cause alkali solubilization of the image recording layer and forms a positive image, an image formed by laser exposure is used as an image forming principle. Since a subtle change in the intermolecular interaction of the binder in the recording layer is used, the difference in the degree of on / off of alkali solubilization in the exposed / unexposed portion is reduced. For this reason, for the purpose of obtaining a clear discrimination that can withstand practical use, an image recording layer structure in which a poorly surface-solubilized layer with respect to a developer is provided as the uppermost layer of the image recording layer to suppress development solubility in unexposed areas is formed. Is used.
[0008]
However, when the surface-solubilized layer is damaged for some reason, even the portion that originally becomes the image portion is likely to be dissolved in the developer. In other words, it has become a printing plate that is very easily damaged. For this reason, scratch-like image loss may occur due to slight contact such as bumping during handling of the printing plate, slight rubbing on the interleaf, and finger contact with the plate surface. The current situation is difficult. In order to improve the susceptibility to scratches, attempts have been made to lower the coefficient of friction by providing a fluorosurfactant or wax agent layer on the surface of the image recording layer, but this is still not a sufficient measure. Absent.
[0009]
In addition, scratch-like image loss due to contact as described above is also a problem in thermal positive type lithographic printing plate precursors in which the image recording layer does not have a surface poorly soluble layer, and in thermal negative type lithographic printing plate precursors. It has become.
[0010]
In recent years, attempts have been made to smooth the surface of the image recording layer for the purpose of improving the above-described scratch resistance. This is in view of the fact that when the irregularities on the surface of the image recording layer are deformed, the surface-solubilized layer is destroyed and the developer is likely to penetrate. In order to realize a flat image recording layer surface, it is effective to make the surface shape of the support as flat as possible. However, if the surface shape of the support is simply flattened, the image recording layer and the support are separated from each other. On the other hand, in order to secure the adhesion between the image recording layer and the support, simply increasing the contact area between the image recording layer and the support by a method such as mechanical roughening treatment, Unevenness is formed on the surface of the recording layer, and the image recording layer is easily damaged.
Therefore, it is extremely difficult to achieve both the prevention of scratches by flattening the surface of the image recording layer and ensuring sufficient printing performance with excellent adhesion between the image recording layer and the support. there were.
[0011]
In addition, by providing irregularities with a wavelength of about 0.4 μm or less on the rough surface, it is possible to improve the adhesion between the image recording layer and the support without causing a change in the shape of the surface of the image recording layer. However, since the image recording layer is difficult to be removed during development, there is a problem that the amount of exposure necessary for development increases, that is, the sensitivity decreases.
[0012]
  Therefore, the present invention is a lithographic printing plate precursor that is not easily scratched, has high sensitivity, has excellent printing performance, and is easy to handle in normal operations.EditionThe purpose is to provide.
[0013]
[Means for Solving the Problems]
  As a result of intensive studies to achieve the above object, the present inventor completed the present invention.
  That is, the present invention relates to a support for a lithographic printing plate obtained by subjecting an aluminum plate to roughening treatment, alkali etching treatment and anodizing treatment.A lithographic printing plate precursor provided with an image recording layer thereonBecause
  Of the lithographic printing plate supportOn the surface, a large wave structure with a wavelength of 2 to 10 μm, a medium wave structure consisting of pits with an average diameter of 0.1 to 1.5 μm,The equivalent circle diameter (area equivalent circle diameter) is 0.005 to 0.1 μm.In the anodized film having a small wave structure composed of irregularities and generated by the anodizing treatment, the average pore diameter of micropores is 0 to 15 nm, and the average pore density is 0 to 400 / μm.²InThe
The lithographic printing plate precursor wherein the image recording layer is a thermal positive layer of any one of a thermal positive type, a thermal negative type and an untreated typeI will provide a.
[0014]
As a result of intensive studies on the surface shape of a lithographic printing plate support to solve the above-mentioned problems, the present inventor is able to maintain a high balance between stain resistance and printing durability due to the surface shape. The present invention has been completed by finding out what can be done.
[0015]
Further, the surface of the image recording layer of the planographic printing plate precursor has unevenness due to the unevenness of the support surface. When an object or the like comes into contact with a thermal positive type image recording layer, if the surface of the image recording layer is rubbed by the object or the like, the top portion of the convex portion is slightly scraped off, and the surface hardly soluble layer is destroyed, sometimes supporting. The body is partially exposed. At the time of development, the developer tends to permeate into the interface between the support and the image recording layer from the portion where the surface hardly soluble layer is broken, so that the image recording layer starts to dissolve from the vicinity of the interface with the support. That is, it is preferentially developed from the rubbed place. Therefore, when viewed macroscopically, the scratch portion is observed as a white line.
[0016]
  The present inventor has obtained the above findings as a result of earnest research. Then, in order to increase the surface area of the support and ensure the adhesion between the image recording layer and the support while reducing the unevenness on the surface of the image recording layer and smoothing, the surface of the support has a wavelength of 2 to 2. A 10 μm large wave structure, a medium wave structure consisting of pits with an average diameter of 0.1 to 1.5 μm,The equivalent circle diameter (area equivalent circle diameter) is 0.005 to 0.1 μm.It has been found that scratches are less likely to occur by forming a large, medium and small triple structure having a small wave structure made up of irregularities.
[0017]
Furthermore, since the image recording layer that has entered the fine irregularities inside the pits constituting the small wave structure is difficult to be removed only by using the above structure, it is necessary to improve developability (sensitivity) to compensate for it.
The present inventor entered the micropores by setting the average pore diameter and the average pore density of the micropores in the anodized film to a specific range smaller than usual on the surface of the support having the shape of the large, medium, and small triple structures. It has been found that the amount of the image recording layer can be reduced and that the developing solution can be prevented from penetrating the inside of the micropore and the permeation rate of the entire image recording layer from being lowered, thereby preventing damage and sensitivity. The present invention was completed by finding that a lithographic printing plate precursor having a high printing performance and high printing performance can be realized.
[0018]
It is preferable that the content of Cu in the aluminum plate is 0 to 0.005 mass%. That is, it is preferable that either Cu is not included at all or 0.005% by mass or less is included. When the Cu content in the aluminum plate is 0 to 0.005% by mass, the pits constituting the medium wave structure are more uniformly formed, so that the adhesion between the image recording layer and the support becomes higher.
[0019]
BookThe planographic printing plate precursor of the invention isHaving the above-mentioned surfaceSince the lithographic printing plate support is used, the balance between the stain resistance and the printing durability that could not be removed from the conventional trade-off relationship can be maintained at a high level.
[0020]
  Furthermore, the present invention relates to a lithographic printing plate precursor comprising an image recording layer which is alkali-solubilized by heating or radiation irradiation on the lithographic printing plate support, and image recording cured by heating or radiation irradiation. A lithographic printing plate precursor provided with a layer is provided. The planographic printing plate precursor of the present invention isHaving the above-mentioned surfaceBecause a lithographic printing plate support is used, it is less likely to be scratched, has higher sensitivity, has better printing performance, and is easier to handle in normal operations than conventional thermal positive and thermal negative lithographic printing plate precursors. . According to the present invention, the susceptibility to scratches, which is an essential problem particularly in a thermal positive type lithographic printing plate precursor, can be greatly improved.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
  The present invention is described in detail below.
[Support for lithographic printing plate]
  <Aluminum plate (rolled aluminum)>
  Of the present inventionUsed for lithographic printing plate precursorsSupport for lithographic printing plate(Hereinafter referred to as “support for lithographic printing plate of the present invention”.)The aluminum plate used for is a metal whose main component is dimensionally stable aluminum, and is made of aluminum or an aluminum alloy. In addition to a pure aluminum plate, an alloy plate containing aluminum as a main component and containing a trace amount of foreign elements, or a plastic film or paper on which aluminum or an aluminum alloy is laminated or vapor-deposited can also be used. Furthermore, a composite sheet in which an aluminum sheet is bonded to a polyethylene terephthalate film as described in Japanese Patent Publication No. 48-18327 can also be used.
[0022]
In the following description, various substrates made of aluminum or an aluminum alloy listed above are collectively used as an aluminum plate. The foreign elements that may be contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, titanium, and the content of the foreign elements in the alloy is 10% by mass or less. It is. In particular, the copper content is preferably 0 to 0.005 mass%.
[0023]
In the present invention, it is preferable to use a pure aluminum plate. However, it is difficult to produce completely pure aluminum in terms of refining technology, so it may contain a slightly different foreign element. Thus, the composition of the aluminum plate used in the present invention is not specified, and conventionally known and used materials such as JIS A1050, JIS A1100, JIS A3005, JIS A3004, internationally registered alloy 3103A, etc. These aluminum alloy plates can be used as appropriate. Further, the aluminum plate may be manufactured by either a continuous casting method or a DC casting method, and an aluminum plate in which DC casting method intermediate annealing or soaking treatment is omitted can also be used. In the final rolling, it is possible to use an aluminum plate provided with irregularities by lamination rolling or transfer. Moreover, the thickness of the aluminum plate used for this invention is about 0.1-0.6 mm. This thickness can be appropriately changed according to the size of the printing press, the size of the printing plate, and the user's desire.
[0024]
The lithographic printing plate support of the present invention is obtained by subjecting the aluminum plate to a surface roughening treatment, an alkali etching treatment and an anodizing treatment. Various processes other than the etching process and the anodizing process may be included.
[0025]
<Roughening treatment (graining treatment)>
The aluminum plate is grained to a more preferable shape. Examples of the graining method include mechanical graining (mechanical surface roughening), chemical etching, and electrolytic grain as disclosed in JP-A-56-28893. In addition, electrochemical graining (electrochemical roughening, electrolytic graining), which is electrochemically grained in hydrochloric acid electrolyte or nitric acid electrolyte, or the aluminum surface is scratched with metal wire Mechanical graining methods (mechanical roughening treatment) such as brush grain method, ball grain method to grain the aluminum surface with abrasive balls and abrasives, brush grain method to grain the surface with nylon brush and abrasives, etc. Can be used. These graining methods can be used alone or in combination. For example, a combination of a mechanical surface roughening treatment with a nylon brush and an abrasive and an electrolytic surface roughening treatment with a hydrochloric acid electrolytic solution or a nitric acid electrolytic solution, or a combination of a plurality of electrolytic surface roughening treatments may be mentioned.
In particular, it is preferable to perform an electrolytic surface roughening treatment after performing a mechanical surface roughening treatment because the surface of the obtained lithographic printing plate support is likely to have a double structure of a large wave structure and a medium wave structure described later.
[0026]
In the case of the brush grain method, the long wavelength of the surface of the aluminum support is selected by appropriately selecting the conditions such as the average particle size, maximum particle size, bristle diameter of the brush used, density, indentation pressure, etc. The average depth of the concave portion of the component (large wave) can be controlled. The recesses obtained by the brush grain method preferably have an average wavelength of 2 to 10 μm and an average depth of 0.2 to 1 μm.
[0027]
As the electrochemical surface roughening method, an electrochemical method in which graining is chemically performed in a hydrochloric acid electrolytic solution or a nitric acid electrolytic solution is preferable. The preferred current density is 50 to 400 C / dm in terms of electricity at the time of anode.²It is. More specifically, for example, in an electrolytic solution containing 0.1 to 50% by mass of hydrochloric acid or nitric acid, the temperature is 20 to 100 ° C., the time is 1 second to 30 minutes, and the current density is 100 to 400 C / dm.²It is performed using direct current or alternating current under the following conditions. According to the electrolytic surface-roughening treatment, it is easy to impart pits to the surface, so that the adhesion between the image recording layer and the support can be increased.
[0028]
By electrolytic surface roughening after mechanical surface roughening, crater-like or honeycomb-like pits having an average diameter of 0.1 to 1.5 μm and an average depth of 0.05 to 0.4 μm (wavelength shorter than the above large wave) ) (Wavelength component (medium wave) recesses) of the surface of the aluminum plate is generated at an area ratio of 90 to 100%, and a double structure of a large wave structure and a medium wave structure can be formed. That is, a large wave having an average wavelength of 2 to 10 μm is formed by the mechanical surface roughening treatment, and a pit, that is, a medium wave is formed by the electrolytic surface roughening treatment.
In the case where only the electrolytic surface roughening treatment is performed without performing the mechanical surface roughening treatment, the average depth of the pits is preferably less than 0.3 μm. For example, by performing the electrolytic surface-roughening treatment twice or more preferably under different conditions without performing mechanical surface-roughening treatment, a large wave structure with an average wavelength of 2 to 10 μm and an average pit diameter of 0.1 to 1 are performed. It is also possible to form a double structure having a medium wave structure of .5 μm.
The provided pits have the effect of improving the resistance to contamination of the non-image area of the printing plate and the printing durability. In the electrolytic surface roughening treatment, an amount of electricity necessary for providing sufficient pits on the surface, that is, the product of the current and the time during which the current flows is an important condition. From the viewpoint of energy saving, it is desirable that sufficient pits can be formed with a smaller amount of electricity.
The surface roughness after the roughening treatment is an arithmetic average roughness (R) measured at a cutoff value of 0.8 mm and an evaluation length of 3.0 mm in accordance with JIS B0601-1994._a) Is preferably 0.2 to 0.5 μm.
[0029]
<Alkaline etching treatment>
The grained aluminum plate is chemically etched with alkali.
The alkali agent suitably used in the present invention is not particularly limited, and examples thereof include caustic soda, sodium carbonate, sodium aluminate, sodium metasilicate, sodium phosphate, potassium hydroxide, and lithium hydroxide.
The conditions for the alkali etching treatment are such that the dissolved amount of Al is 0.05 to 30 g / m.²It is preferable to carry out under such conditions. The other conditions are not particularly limited, but the alkali concentration is preferably 1 to 50% by mass, more preferably 5 to 30% by mass, and the alkali temperature is 20 to 100 ° C. It is preferable that it is, and it is more preferable that it is 30-50 degreeC.
The alkali etching treatment is not limited to one method, and a plurality of steps can be combined.
The alkali etching process is not limited to a one-stage process. For example, after performing a mechanical surface roughening treatment, an alkali etching treatment is performed, followed by a desmut treatment (pickling to remove smut described later), an electrolytic surface roughening treatment, and then an alkali etching again. The alkali etching treatment and the desmut treatment can be combined and performed a plurality of times, for example, by performing the treatment and subsequently performing the desmut treatment.
[0030]
  By this alkali etching treatment, the average diameter of the pits can be controlled to 0.1 to 1.5 μm, and at the same time, a small wave structure composed of fine irregularities can be formed inside the pits. The fine irregularities are irregular,Area equivalent circle diameterCan be, for example, 0.005 to 0.1 μm.
  Therefore, since a double structure of a large wave structure and a medium wave structure is formed by the roughening treatment, a large, medium, and small triple structure can be formed by forming the small wave structure by the alkali etching treatment. Therefore, it is necessary to select the conditions for the alkali etching treatment so as to form a large, medium, and small triple structure.
[0031]
After performing the alkali etching treatment, pickling (desmut treatment) is performed in order to remove dirt (smut) remaining on the surface. Examples of the acid used include nitric acid, sulfuric acid, phosphoric acid, chromic acid, hydrofluoric acid, and borohydrofluoric acid. In particular, as a method for removing smut after the electrolytic surface-roughening treatment, it is preferably brought into contact with 15 to 65 mass% sulfuric acid at a temperature of 50 to 90 ° C. as described in JP-A-53-12739. A method is mentioned.
[0032]
<Anodizing treatment>
The aluminum plate treated as described above is further subjected to anodizing treatment. At this time, in order to suppress the sensitivity decrease due to the micropores, the average pore diameter of the micropores in the anodized film is set to 0 to 15 nm, and the average pore density is set to 0 to 400 / μm.²Is necessary. That is, in the lithographic printing plate support of the present invention, the anodic oxide coating may or may not have micropores, and in the case of having micropores, the average pore diameter is 15 nm or less. The average pore density is 400 / μm.²It is as follows. Among these, it is preferable that the anodized film does not have micropores from the viewpoint of excellent sensitivity.
The anodizing treatment can be performed by a method conventionally used in this field. Specifically, when direct current or alternating current is applied to an aluminum plate in an aqueous solution containing sulfuric acid as a main component and, if necessary, combined with phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, etc., aluminum An anodized film can be formed on the surface of the plate.
[0033]
Under the present circumstances, the component normally contained at least by Al alloy plate, an electrode, tap water, groundwater, etc. may be contained in electrolyte solution. Furthermore, the 2nd, 3rd component may be added. Examples of the second and third components herein include metal ions such as Na, K, Mg, Li, Ca, Ti, Al, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn; Cation such as ammonium ion; anion such as nitrate ion, carbonate ion, chloride ion, phosphate ion, fluoride ion, sulfite ion, titanate ion, silicate ion, borate ion, etc., 0 to 10,000 ppm It may be contained at a concentration of about.
[0034]
The conditions for anodizing treatment vary depending on the electrolyte used, and thus cannot be determined unconditionally. In general, the electrolyte concentration is 1 to 15% by mass, the solution temperature is -5 to 40 ° C., and the current density is 5 to 5. 60A / dm²A voltage of 1 to 20 V and an electrolysis time of 10 to 200 seconds are appropriate.
[0035]
In the present invention, the amount of the anodized film is 1 to 5 g / m.²Is preferred. 1g / m²If it is less than 5%, the plate is likely to be damaged, while 5 g / m.²Exceeding this requires a large amount of power for production, which is economically disadvantageous. The amount of anodized film is 1.5-4 g / m²It is more preferable that
[0036]
<Alkali metal silicate treatment>
The aluminum support on which the anodic oxide film obtained by the treatment as described above is formed is dipped using an aqueous solution of an alkali metal silicate as necessary. The treatment conditions are not particularly limited. For example, the treatment conditions are immersed in an aqueous solution having a concentration of 0.01 to 5.0 mass% at a temperature of 5 to 40 ° C. for 1 to 60 seconds, and then washed with running water. A more preferable immersion treatment temperature is 10 to 40 ° C., and a more preferable immersion time is 2 to 20 seconds.
[0037]
Examples of the alkali metal silicate used in the present invention include sodium silicate, potassium silicate, and lithium silicate.
The aqueous solution of alkali metal silicate may contain an appropriate amount of sodium hydroxide, potassium hydroxide, lithium hydroxide or the like.
The aqueous solution of alkali metal silicate may contain an alkaline earth metal salt or a Group 4 (Group IVA) metal salt. Examples of the alkaline earth metal salt include nitrates such as calcium nitrate, strontium nitrate, magnesium nitrate, and barium nitrate; sulfates; hydrochlorides; phosphates; acetates; oxalates; Examples of the Group 4 (Group IVA) metal salt include titanium tetrachloride, titanium trichloride, potassium fluoride titanium, potassium oxalate, titanium sulfate, titanium tetraiodide, zirconium chloride, zirconium dioxide, zirconium oxychloride. And zirconium tetrachloride. These alkaline earth metal salts and Group 4 (Group IVA) metal salts are used alone or in combination of two or more.
[0038]
The amount of Si adsorbed by the alkali metal silicate treatment is measured by a fluorescent X-ray analyzer, and the amount of adsorption is about 1.0 to 15.0 mg / m.²Is preferred.
By this alkali metal silicate treatment, an effect of improving the solubility resistance of the aluminum support surface to the alkaline developer is obtained, and the dissolution of the aluminum component into the developer is suppressed. Can be reduced.
[0039]
<Sealing treatment>
After the anodizing treatment, a sealing treatment may be performed as desired. The sealing treatment is performed by a method of immersing the anodized support in hot water or a hot aqueous solution containing an inorganic salt or an organic salt, a method of exposing it to a steam bath, or the like. Specifically, for example, sealing treatment with pressurized steam or hot water described in JP-A-4-176690 and JP-A-11-301135 can be mentioned.
In the lithographic printing plate support of the present invention, when the sealing treatment is performed, the average pore diameter of the micropores in the anodic oxide film after the sealing treatment is 0 to 15 nm, and the average pore density is 0 to 400 / μm.²If so, the micropores in the anodized film before the sealing treatment may not satisfy these.
<Interface control processing>
Further, after the anodizing treatment, an interface control treatment such as a hydrophilic treatment may be performed as desired.
As the interface control treatment, in addition to the alkali metal silicate treatment described above, potassium fluoride zirconate disclosed in Japanese Patent Publication No. 36-22063, US Pat. No. 3,276,868, A method of treating with polyvinylphosphonic acid as disclosed in US Pat. Nos. 4,153,461 and 4,689,272 is used.
[0040]
For the details of each process described in the above items, known conditions can be adopted as appropriate. Further, the contents of the documents cited in this specification are cited as the contents of this specification.
[0041]
[Lithographic printing plate precursor]
The lithographic printing plate support of the present invention can be provided with an image recording layer such as a photosensitive layer and a heat-sensitive layer exemplified below to form the lithographic printing plate precursor of the present invention. The image recording layer is not particularly limited, and for example, a conventional positive type, a conventional negative type, a photopolymer type, a thermal positive type, a thermal negative type, and an on-machine developable non-processing type are preferable. Hereinafter, these suitable image recording layers will be described in detail.
[0042]
<Conventional positive type>
The positive photosensitive resin composition used in the lithographic printing plate precursor of the present invention having a conventional positive type photosensitive layer can be used as long as the solubility or swellability in a developer changes before and after exposure. As a preferable thing contained in it, an o-quinonediazide compound is mentioned. For example, in the case of a positive photosensitive resin composition containing a water-insoluble and alkali-soluble polymer compound (hereinafter referred to as “alkali-soluble polymer compound”) and an o-quinonediazide compound, the o-quinonediazide compound is at least A compound having one o-quinonediazide group that increases the solubility in an alkaline aqueous solution by actinic rays is preferable.
[0043]
As such, various structures are known. KOSAR, “Light-Sensitive Systems” (John Wiley & Sons, Inc, 1965) p. 336-352. As the o-quinonediazide compound, sulfonic acid esters using various hydroxy compounds and o-benzoquinonediazide or o-naphthoquinonediazide as raw materials are particularly suitable.
[0044]
Examples of such o-quinonediazide compounds include esters of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and phenol-formaldehyde resin or cresol-formaldehyde resin; U.S. Pat. No. 3,635,709. Esters of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and pyrogallol acetone resin described in the specification; 1,2-naphthoquinone described in JP-B-63-13528 Ester of 2-diazide-5-sulfonyl chloride and resorcin-benzaldehyde resin; 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and resorcin-pyrogallol described in JP-B-62-44,257 With acetone co-condensation resin Tel;
[0045]
A polyester having 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride esterified to a polyester having a hydroxy group at the terminal described in JP-B-56-45,127; 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride is esterified to a homopolymer of N- (4-hydroxyphenyl) methacrylamide or a copolymer with other copolymerizable monomers described in the publication Ester of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and bisphenol-formaldehyde resin described in JP-B-54-29,922; JP-B-52-36,043 P-hydroxystyrene homopolymers or other copolymerizations described in the publication 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride esterified to a copolymer with nomer; ester of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and polyhydroxybenzophenone is there.
[0046]
Other known o-quinonediazide compounds that can be used in the present invention include JP-A-63-80254, JP-A-58-5737, JP-A-57-111530, JP-A-57-111531, and JP-A-51-111531. In Japanese Patent Publication Nos. 57-114138, 57-142635, 51-36129, 62-3411, 62-51459, 51-483, etc. Can be mentioned. Content of o-quinonediazide compound is 5-60 mass% normally with respect to the total solid of the photosensitive resin composition, Preferably it is 10-40 mass%.
[0047]
As the photosensitive compound other than the o-quinonediazide compound, it is possible to use a chemically amplified photosensitive material (light irradiation sensitive mixture) comprising a combination of a compound in which an alkali-soluble group is protected with an acid-decomposable group and a photoacid generator. it can.
[0048]
As the photoacid generator used for the chemically amplified photosensitive material, known photoacid generators can be used. For example, S.M. I. Schlesinger, Photogr. Sci. Eng. , 18, 387 (1974), T.A. S. Diazonium salts described in Bal et al, Polymer, 21, 423 (1980), U.S. Pat. Nos. 4,069,055, 4,069,056, JP-A-3-140140 Ammonium salts described in the above, and the like. C. Necker et al, Macromolecules, 17, 2468 (1984), C.I. S. Wen et al, Teh, Proc. Conf. Rad. Curing ASIA, p. 478 Tokyo, Oct (1988), U.S. Pat. Nos. 4,069,055 and 4,069,056, etc. V. Crivello et al, Macromolecules, 10 (6), 1307 (1977), Chem. & Eng. News, Nov. 28, p. 31 (1988), European Patent Nos. 104,143, U.S. Pat. Nos. 339,049 and 410,201, JP-A-2-150848, JP-A-2-296514, etc. The iodonium salts described, J. V. Crivello et al, Polymer J. et al. 17, 73 (1985), J. Am. V. Crivello et al. J. et al. Org. Chem. 43, 3055 (1978); R. Wattet al, J. et al. Polymer Sci. , Polymer Chem. Ed. , 22, 1789 (1984), J. Am. V. Crivello et al, Polymer Bull. 14, 279 (1985), J. Am. V. Crivello et al, Macromolecules, 14 (5), 1141 (1981), J. MoI. V. Crivello et al, J.A. Polymer Sci. , Polymer Chem. Ed. 17, 2877 (1979), European Patent No. 370,693, US Patent No. 3,902,114, European Patent Nos. 233,567, 297,443, 297,442, US Patent No. 4 933,377, 410,201, 339,049, 4,760,013, 4,734,444, 2,833,827, German Patent 2,904, Sulfonium salts described in the specifications of No. 626, No. 3,604,580, No. 3,604,581, etc.,
[0049]
J. et al. V. Crivello et al, Macromolecules, 10 (6), 1307 (1977), J. MoI. V. Crivello et al, J.A. Polymer Sci. , Polymer Chem. Ed. , 17, 1047 (1979), etc., selenonium salts, C.I. S. Wen et al, Teh, Proc. Conf. Rad. Curing ASIA, p. 478 Onium salts such as arsonium salts described in Tokyo, Oct (1988), etc .; US Pat. No. 3,905,815, Japanese Examined Patent Publication No. 46-4605, Japanese Unexamined Patent Publication No. 48-36281, JP 55-23070, JP 60-239736, JP 61-169835, JP 61-169837, JP 62-58241, JP 62-212401, JP 63- Organic halogen compounds described in JP-A-70243, JP-A-63-298339, and the like; Meier et al, J.A. Rad. Curing, 13 (4), 26 (1986), T.A. P. Gill et al, Inorg. Chem. , 19, 3007 (1980), D.M. Astruc, Acc. Chem. Res. , 19 (12), 377 (1896), JP-A-2-161445, etc .; organometallic / organic halides; Hayase et al, J.A. Polymer Sci. 25, 753 (1987), E.I. Reichmanis et al. Polymer Sci. , Polymer Chem. Ed. , 23, 1 (1985), Q.M. Q. Zhu et al, J.A. Photochem. 36, 85, 39, 317 (1987), B.R. Amit et al, Tetrahedron Lett. , (24), 2205 (1973), D.M. H. R. Barton et al, J.A. ChemSoc. , 3571 (1965), p. M.M. Collins et al, J.A. Chem. Soc. Perkin I, 1695 (1975), M .; Rudinstein et al, Tetrahedron Lett. , (17), 1445 (1975), J. MoI. W. Walker et al. Am. Chem. Soc. 110, 7170 (1988), S.A. C. Busman et al, J.M. ImagingTechnol. 11 (4), 191 (1985), H. et al. M.M. Houlihan et al, Macormolecules, 21, 2001 (1988), P.M. M.M. Collins et al, J.A. Chem. Soc. , Chem. Commun. 532 (1972), S.A. Hayase et al, Macromolecules, 18, 1799 (1985); Reichmanis et al. Electrochem. Soc. , Solid State Sci. Technol. , 130 (6), F.M. M.M. Houlihan et al, Macromolecules, 21, 2001 (1988), European Patent Nos. 0290,750, 046,083, 156,535, 271,851, 0,388,343, US Patent No. O-Nitrobenzyl type protecting group described in each specification of 3,901,710, 4,181,531, JP-A-60-198538, JP-A-53-133022, etc. A photoacid generator having:
[0050]
M.M. Tunook et al, Polymer Preprints Japan, 35 (8), G.M. Berner et al, J.A. Rad. Curing, 13 (4), W.M. J. et al. Mijs et al, Coating Technol. , 55 (697), 45 (1983), Akzo, H .; Adachi et al, Polymer Preprints, Japan, 37 (3), European Patent Nos. 0199,672, 84515, 199,672, 044,115, 0101,122, US Pat. No. 4,618, 564, 4,371,605, 4,431,774, JP-A 64-18143, JP-A-2-245756, JP-A-4-365048, etc. Examples thereof include compounds that generate photosulfonic acid by photolysis, such as iminosulfonates, and the like; and disulfone compounds described in JP-A No. 61-166544.
[0051]
The amount of the compound (photoacid generator) that generates acid upon decomposition by irradiation with actinic rays or radiation is usually 0.001 to 40% by mass with respect to the total solid content of the photosensitive resin composition. It is preferable that it is 0.01-20 mass%, and it is more preferable that it is 0.1-5 mass%.
[0052]
A compound in which an alkali-soluble group is protected with an acid-decomposable group (a compound that can be cleaved by an acid) is a compound having a —C—O—C— bond or a —C—O—Si— bond. Can be mentioned.
(A) including at least one orthocarboxylic acid ester and a carboxylic acid amide acetal group, wherein the compound can have polymerizability, the above group as a bridging element in the main chain, or lateral substitution A compound that can occur as a group,
(B) an oligomeric or polymeric compound containing in the main chain selected from repeating acetal and ketal groups,
(C) a compound comprising at least one enol ester or N-acylamino carbonate group,
(D) β-ketoester or β-ketoamide cyclic acetal or ketal,
(E) a compound containing a silyl ether group,
(F) a compound containing a silyl enol ether group,
(G) a monoacetal or monoketal in which the aldehyde or ketone component has a solubility of 0.1 to 100 g / L with respect to the developer;
(H) Tertiary alcohol ethers,
(I) Carboxylic acid esters and carbonates of tertiary allylic or benzylic alcohols.
[0053]
The compound of the above (a), which is a compound that can be cleaved by an acid as a component of the light-sensitive mixture, is described in DE-A-2,610,842 and DE-A-2,928,636. It is described in. The mixture containing the compound (b) is described in German Patent Nos. 2,306,248 and 2,718,254. The compound (c) is described in EP-A-0,006,626 and JP-A-0,006,627. The compound (d) is described in EP 0,202,196. The compound (e) is described in German Patent Application Publication Nos. 3,544,165 and 3,601,264. The compound of (f) is described in German Patent Application Publication Nos. 3,730,785 and 3,730,783. The compound (g) is described in DE-A-3,730,783. The compound (h) is described in, for example, US Pat. No. 4,603,101. The compound of the above (i) is described in, for example, US Pat. No. 4,491,628 and J. Pat. M.M. Frechet et al. (J. Imaging Sci. 30, 59-64 (1986)).
The content of the compound in which these alkali-soluble groups are protected with an acid-decomposable group is usually 1 to 60% by mass, preferably 5 to 40% by mass, based on the total solid content of the photosensitive resin composition. .
[0054]
The photosensitive resin composition may contain an alkali-soluble polymer compound.
Examples of the alkali-soluble polymer compound include phenol / formaldehyde resin, cresol / formaldehyde resin, phenol / cresol / formaldehyde co-condensation resin, phenol-modified xylene resin, polyhydroxystyrene, polyhalogenated hydroxystyrene, N- (4-hydroxy). Phenyl) methacrylamide copolymer, hydroquinone monomethacrylate copolymer, sulfonylimide polymer described in JP-A-7-28244, carboxy group-containing polymer described in JP-A-7-36184, etc. Is mentioned. Further, acrylic resins containing phenolic hydroxy groups as described in JP-A-51-34711, acrylic resins having sulfonamide groups as described in JP-A-2-866, and urethane Various alkali-soluble polymer compounds such as resins can also be used.
These alkali-soluble polymer compounds preferably have a weight average molecular weight of 500 to 200,000 and a number average molecular weight of 200 to 60,000. The alkali-soluble polymer compound may be used alone or in combination of two or more, and is used at a content of 80% by mass or less based on the total solid content of the photosensitive resin composition.
[0055]
Furthermore, as described in US Pat. No. 4,123,279, phenol and formaldehyde having an alkyl group having 3 to 8 carbon atoms as a substituent, such as t-butylphenol formaldehyde resin and octylphenol formaldehyde resin. It is preferable to use a condensate together with the above in order to improve the oil sensitivity of the image. Such an alkali-soluble polymer compound is usually used at a content of 90% by mass or less based on the total solid content of the photosensitive resin composition.
[0056]
In the photosensitive resin composition, if necessary, a cyclic acid anhydride for increasing the sensitivity, a print-out agent for obtaining a visible image immediately after exposure, a dye as an image colorant, other fillers, etc. Can be added.
[0057]
In the photosensitive resin composition, it is preferable to add cyclic acid anhydrides, phenols and organic acids in order to increase sensitivity.
Specific examples of the cyclic acid anhydride include compounds described in US Pat. No. 4,115,128.
[0058]
Examples of organic acids include sulfonic acids, sulfinic acids, alkylsulfuric acids, phosphonic acids, phosphinic acids, phosphoric esters, and carbonic acids described in JP-A-60-88942 and JP-A-2-96755. Examples include acids.
[0059]
The total content of the cyclic acid anhydrides, phenols and organic acids is preferably 0.05 to 15% by mass with respect to the total solid content of the photosensitive resin composition, More preferably, it is 5 mass%.
[0060]
Examples of the print-out agent for obtaining a visible image immediately after exposure include a combination of a photosensitive compound that releases an acid by exposure and an organic dye that forms a salt with the acid to change the color tone.
[0061]
Examples of the photosensitive compound that releases an acid upon exposure used as a print-out agent include o-naphthoquinonediazide compounds described in JP-A-50-36209 and JP-A-55-62444; Trihalomethyl-2-bilone and trihalomethyl-s-triazine described in JP-A-53-36223; 2-trihalomethyl-5-aryl-1,3 described in JP-A-55-77742 4-oxadiazole compounds; diazonium salts and the like. These compounds can be used alone or in combination, and the content thereof is preferably 0.3 to 15% by mass with respect to the total solid content of the photosensitive resin composition.
[0062]
In the photosensitive resin composition, it is preferable to use at least one organic dye that changes its color tone by interacting with a photodecomposition product of a compound that generates an acidic substance by photolysis.
Examples of such organic dyes include diphenylmethane, triarylmethane, thiazine, oxazine, phenazine, xanthene, anthraquinone, iminonaphthoquinone, and azomethine dyes. Specifically, for example, compounds described in JP-A Nos. 50-36209 and 55-77742 are listed.
[0063]
Particularly preferred organic dyes are triarylmethane dyes. Among triarylmethane dyes, those having a sulfonic acid compound as a counter anion as described in JP-A-62-293471 and JP-A-5-313359 are particularly useful.
[0064]
These dyes can be used alone or as a mixture, and the content thereof is preferably 0.3 to 15% by mass with respect to the total solid content of the photosensitive resin composition. Further, it can be used in combination with other dyes and pigments as necessary, and the amount used is preferably 70% by mass or less, more preferably 50% by mass or less, based on the total mass of the dye and pigment. preferable.
[0065]
The lithographic printing plate precursor of the present invention is obtained by dissolving or dispersing each component of the photosensitive resin composition in a solvent and applying the solution on the lithographic printing plate support of the present invention.
Specific examples of the solvent include alcohols (methanol, ethanol, isopropanol, tetrahydrofurfuryl alcohol, diacetone alcohol, ethylene glycol, propylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 1-methoxy- 2-propanol), hydrocarbons (toluene, cyclohexane, etc.), halogenated hydrocarbons (ethylene dichloride, etc.), ketones (acetone, acetylacetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), esters (ethyl acetate, Methyl lactate, ethyl lactate, 2-methoxyethyl acetate, 1-methoxy-2-propyl acetate, etc.), ethers (ethylene glycol dimethyl ether, die Lenglycol dimethyl ether, propylene glycol diethyl ether, etc.), amides (dimethylacetamide, dimethylformamide, N-methylpyrrolidone, etc.), γ-butyrolactone, dimethyl sulfoxide, water and mixtures of these solvents Can do.
[0066]
Various methods can be used as the coating method, and examples thereof include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, and roll coating.
[0067]
<Conventional negative type>
Examples of the negative photosensitive resin composition used in the lithographic printing plate precursor of the present invention having a conventional negative type photosensitive layer include a diazo resin and an alkali-soluble or swellable polymer compound (binder). Is mentioned.
Examples of the diazo resin used in the negative photosensitive resin composition include a condensate of an aromatic diazonium salt and an active carbonyl group-containing compound such as formaldehyde. Examples of the diazo resin include organic solvent-soluble diazo resin inorganic substances which are reaction products of a condensate of p-diazophenylamines with aldehydes such as formaldehyde and acetaldehyde and hexafluorophosphate or tetrafluoroborate. Salt; the condensate as described in JP-B-47-1167 and sulfonates such as p-toluenesulfonic acid, propylnaphthalenesulfonic acid, butylnaphthalenesulfonic acid, dibutylnaphthalenesulfonic acid, dodecyl Examples include organic solvent-soluble diazo resin organic salts which are reaction products of benzenesulfonic acid and 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid. In particular, a high molecular weight diazo compound containing 20 mol% or more of a hexamer described in JP-A-59-78340 is preferable. Also, a mesitylene sulfonate salt obtained by condensing 3-methoxy-4-diazo-diphenylamine with 4,4'-bis-methoxy-methyl-diphenyl ether as described in JP-A-58-27141 Is also appropriate. Further, a co-condensed diazo resin with an aromatic compound described in JP-B-49-48001, or a co-condensed diazo resin with an aromatic compound having an acid group described in JP-A-2-29650 Are also preferably used. Further, a diazo resin condensed with an aldehyde having an acid group or an acetal compound described in JP-A-4-18559 can also be preferably used. Further, an aromatic compound having at least one organic group selected from the group consisting of a carboxy group, a sulfo group, a sulfinic acid group, a phosphorus oxyacid group and a hydroxy group, and a diazonium compound, preferably an aromatic diazonium compound. Cocondensates containing as units are also preferred.
These diazo resins may be used alone or as a mixture of two or more. The content of the diazo resin is preferably 1 to 70% by mass and more preferably 3 to 60% by mass with respect to the total solid content of the photosensitive layer.
[0068]
The alkali-soluble or swellable polymer compound used in the negative photosensitive resin composition preferably has an acid content of 0.1 to 5.0 meq / g, more preferably 0.2 to 3.0 meq / g. An organic polymer compound that is substantially water-insoluble (ie, insoluble in a neutral or acidic aqueous solution) and has film-forming properties, can be dissolved or swelled in an alkaline developer, and Those that are photocured in the presence of the above-mentioned diazo resin and insolubilized or non-swelled in the developer are preferred. If the acid content is less than 0.1 meq / g, development may be difficult, and if it exceeds 5.0 meq / g, the image strength during development may be significantly weakened.
[0069]
Particularly suitable binders include multi-component copolymers containing acrylic acid, methacrylic acid, crotonic acid or maleic acid as essential components. Examples thereof include multi-component copolymers described in JP-A-50-118802, JP-A-53-120903, JP-A-54-98614 and JP-A-56-4144.
[0070]
As the binder, acidic polyvinyl alcohol derivatives and acidic cellulose derivatives are also useful.
Further, it is described in JP-B-54-19773, JP-A-57-94747, JP-A-60-182437, JP-A-62-58242 and JP-A-62-123453 in which polyvinyl acetal and polyurethane are solubilized with alkali. Also useful are binders.
[0071]
The molecular weight of the binder is preferably 0.5 to 200,000, and more preferably 2 to 150,000.
These binders may be used alone or in combination of two or more.
[0072]
The content of the diazo resin and the binder in the photosensitive layer is suitably 3 to 60% by mass of the diazo resin and 97 to 40% by mass of the binder based on the total amount of both. The smaller the diazo resin content, the higher the sensitivity. However, if it is less than 3% by mass, it is insufficient for photocuring the binder, and the photocured film is swollen by the developer during development, and the film is become weak. On the other hand, when the content of the diazo resin exceeds 60% by mass, the sensitivity is lowered and practically difficult points appear. Preferably, the diazo resin is 5 to 40% by mass and the binder is 95 to 60% by mass.
[0073]
The lithographic printing plate precursor of the present invention is obtained by dissolving each component of the photosensitive resin composition in a solvent that dissolves it and applying the solution onto the lithographic printing plate support of the present invention. As the solvent, when an intermediate layer containing an alkali-soluble polymer compound is provided, a solvent that does not dissolve the alkali-soluble polymer compound is selected. Specifically, for example, the same solvent as in the case of the conventional positive type photosensitive layer described above can be used. As a coating method, various methods similar to those in the case of the conventional positive type photosensitive layer described above can be used.
[0074]
The concentration (solid content) of the above components is suitably 2 to 50% by mass. The coating amount (solid content) is 0.5 to 4.0 g / m.²Is preferred. 0.5g / m²If it is less, the printing durability may deteriorate. 4.0 g / m²If the amount is more than 1, the printing durability is improved, but the sensitivity may be lowered.
[0075]
In the photosensitive resin composition, a surfactant for improving the coating property, for example, a fluorine-based surfactant described in JP-A No. 62-170950 can be added. The addition amount of the fluorosurfactant is preferably 0.01 to 1% by mass, more preferably 0.05 to 0.5% by mass, based on the total solid content of the photosensitive resin composition. preferable.
[0076]
An arbitrary layer may be provided below the conventional negative photosensitive layer. Examples thereof include an intermediate layer containing a polymer compound having a component having an acid group and a component having an onium group, as described in JP-A 2000-105462.
[0077]
<Photopolymer type>
(Photosensitive layer)
The photopolymerizable photosensitive composition (hereinafter referred to as “photopolymerizable composition”) used in the lithographic printing plate precursor of the present invention having a photopolymer type photosensitive layer is an addition-polymerizable compound containing an ethylenically unsaturated bond. (Hereinafter referred to simply as “ethylenically unsaturated bond-containing compound”), a photopolymerization initiator, and a polymer binder as essential components, and if necessary, colorants, plasticizers, and thermal polymerization are prohibited. Contains various compounds such as agents.
[0078]
The ethylenically unsaturated bond-containing compound contained in the photopolymerizable composition is such that, when the photopolymerizable composition is irradiated with actinic rays, it undergoes addition polymerization by the action of the photopolymerization initiator, crosslinks and cures. It is a compound having an ethylenically unsaturated bond. The ethylenically unsaturated bond-containing compound can be arbitrarily selected from compounds having at least one terminal ethylenically unsaturated bond, preferably two or more, such as monomers, prepolymers (ie, dimers). Trimers and oligomers), mixtures thereof, and copolymers thereof.
[0079]
Examples of monomers and copolymers thereof include esters of unsaturated carboxylic acids (eg acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid) with aliphatic polyhydric alcohol compounds, unsaturated carboxylic acids. Examples include amides of acids and aliphatic polyvalent amine compounds.
Specific examples of the aliphatic polyhydric alcohol compound that forms an ester monomer with an unsaturated carboxylic acid include ethylene glycol, triethylene glycol, 1,3-propanediol, 1,3-butanediol, tetramethylene glycol, and propylene glycol. , Neopentyl glycol, trimethylolpropane, trimethylolethane, hexanediol, 1,4-cyclohexanediol, pentaerythritol, dipentaerythritol, sorbitol, tri (2-hydroxyethyl) isocyanurate, bis [p- (3-hydroxy 2-hydroxypropoxy) phenyl] dimethylmethane, bis- [p- (2-hydroxyethyloxy) phenyl] dimethylmethane, and the like.
However, the trivalent or higher alcohol compound may be any as long as it contains at least two polymerizable unsaturated groups in the molecule.
In the present invention, a mixture of these ester monomers can also be used.
[0080]
Specific examples of the aliphatic polyvalent amine compound that forms an amide monomer with an unsaturated carboxylic acid include methylenediamine, ethanediamine, propanediamine, tetramethylenediamine, hexamethylenediamine, diethylenetriamine, xylylenediamine, cyclohexanediamine, and cyclohexanedimethyl. An amine etc. are mentioned.
[0081]
As another example, a polyisocyanate compound having two or more isocyanate groups in one molecule described in JP-B-48-41708 has 2 molecules per molecule in which a vinyl monomer having a hydroxy group is added. Vinyl urethane compounds having at least one polymerizable vinyl group, urethane acrylates as described in JP-A-51-37193 and JP-B-2-32293, JP-A-48-64183, Polyfunctional (meth) acrylates such as polyester acrylates and epoxy acrylates obtained by reacting an epoxy resin and (meth) acrylic acid as described in JP-B Nos. 49-43191 and 52-30490. Can be mentioned.
Furthermore, the Japan Adhesion Association Magazine Vo 1.20, No. 7, p. Those introduced as photocurable monomers and oligomers in 300-308 (1984) can also be used.
[0082]
The content of these ethylenically unsaturated bond-containing compounds is preferably 5 to 80% by mass and more preferably 30 to 70% by mass with respect to the total solid content of the photopolymerizable composition.
[0083]
As the photopolymerization initiator contained in the photopolymerizable composition, various photopolymerization initiators known in patents, literatures, etc., or a combination system of two or more photopolymerization initiators depending on the wavelength of the light source used ( The photoinitiating system) can be appropriately selected and used. Specific examples of the photopolymerization initiator are listed below, but the present invention is not limited thereto.
Various photoinitiating systems have been proposed in the case of using visible light of 400 nm or more, Ar laser, second harmonic of a semiconductor laser, and SHG-YAG laser as a light source. Specific examples of the photopolymerization initiator are listed below, but the present invention is not limited thereto.
Specific examples of the photopolymerization initiator include photoreducible dyes (described in U.S. Pat. No. 2,850,445: Rose Bengal, Eosin, Erythrosin, etc.), amines (described in Japanese Patent Publication No. 44-20189), radicals Generator (described in JP-B-45-37377, JP-A-52-112681, JP-A-58-15503, JP-A-2-17943, and JP-A-2-244050), hexaarylbiimidazole (JP-B-47) -2528 and JP-A-54-155292), cyclic cis-α-dicarbonyl compounds (described in JP-A-48-84183), cyclic triazines (described in JP-A-54-151024), Biimidazole (described in JP-A-59-140203), organic peroxides (JP-A-59-1504, 59-14020) No. 59-189340, No. 62-174203, and Japanese Patent Publication No. 62-1641, as well as US Pat. No. 4,766,055, and active halogen compounds (Japanese Patent Laid-Open No. 63-258903). And JP-A-2-63054), borate compounds (JP-A-62-143044, JP-A-62-1050242, JP-A-64-13140, JP-A-64-13141, JP-A-64-13142, JP-A-64-13143). , JP-A 64-13144, JP-A 64-17048, JP-A-1-229003, JP-A-1-298348, JP-A-1-138204 and JP-A-11-84647), thiol compounds (JP-A-11-84647) No. 59-140203), disulfone compounds (described in JP-A No. 61-166544), titanosenation Compound (Japanese Patent Laid-Open Nos. 59-152396, 61-151197, Japanese Patent Laid-Open Nos. 4-219756, 4-221958, 6-295061, 8-3-334897, Japanese Patent Laid-Open No. 2000-147663, and the like 2001-0442524), iron-arene complexes (described in JP-A-1-304453, JP-A-1-152109, etc.) and the like.
[0084]
In the present invention, a system using a titanocene compound is particularly suitable because it is excellent in sensitivity.
As the titanocene compound, various compounds can be used. For example, various titanocene compounds described in JP-A-59-152396 and JP-A-61-151197 can be appropriately selected and used. .
[0085]
In these photoinitiating systems, in order to enable exposure (photopolymerization) with light, the image recording layer preferably further contains a sensitizing dye or a sensitizing aid. By using a sensitizing dye in combination with the photopolymerization initiator, the photosensitive wavelength region of the photopolymerization initiator can be adjusted.
Preferred dyes to be combined are cyanine, merocyanine, xanthene, ketocoumarin, and benzopyran dyes.
The cyanine dyes are not particularly limited, but those described in JP-A-62-143044 and JP-B-46-42363 are preferable examples.
The merocyanine dye is not particularly limited, but those described in JP-B-61-9621, JP-A-2-17943, and the like are preferably exemplified. Further, a merocyanine dye containing a thiazolidinone ring, imidazoliquinone ring, oxazolidine ring or dithiolanone ring in the methine chain (for example, JP-A-2-244050, JP-B-59-28326, JP-A-59-89303, JP-A-8-129257, etc.) is also preferably exemplified.
The xanthene dye is not particularly limited, but rhodamine B, rhodamine 6G, ethyl eosin, alcohol-soluble eosin, pyronin Y, and pyronin B are preferably exemplified.
The ketocoumarin dyes and benzopyran dyes are not particularly limited, but preferred examples include compounds described in JP-A-8-334897.
[0086]
Furthermore, in addition to the photopolymerization initiator, the photopolymerizable composition contains a known compound having a function of further improving sensitivity or a function of suppressing polymerization inhibition by oxygen as a co-sensitizer. Also good.
Examples of such co-sensitizers include amines (for example, “Journal of Polymer Society”, Vol. 10, p. 3173 (1972) by MR Sander et al. JP-A-51-82102, JP-A-52-134692, JP-A-59-138205, JP-A-60-84305, JP-A-62-18537, and JP-A-64-33104, and , Compounds described in Research Disclosure 33825), thiols and sulfides (for example, compounds described in JP-A-53-702 and JP-B-55-500806), The thiol compound described in Japanese Patent No. 142772 and described in JP-A-56-75643 Disulfide compounds, amino acid compounds (for example, N-phenylglycine, etc.) listed, organometallic compounds (for example, tributyltin acetate, etc.) described in Japanese Patent Publication No. 48-42965, Japanese Patent Publication No. 55-34414 Hydrogen donors described, sulfur compounds described in JP-A-6-308727 (eg, trithiane, etc.), phosphorus compounds described in JP-A-6-250389 (diethylphosphite, etc.), etc. Is mentioned.
[0087]
The content of these photopolymerization initiators or photoinitiating systems is preferably 0.05 to 100 parts by mass, and 0.1 to 70 parts by mass with respect to 100 parts by mass of the ethylenically unsaturated bond-containing compound. More preferably, it is 0.2 to 50 parts by mass.
[0088]
The polymer binder contained in the photopolymerizable composition not only functions as a film-forming agent for the photopolymerizable composition, but also needs to dissolve the photosensitive layer in an alkali developer, so that it is soluble in alkaline water or Swelling organic high molecular polymers are used. As such an organic polymer, for example, when a water-soluble organic polymer is used, water development becomes possible.
Examples of such organic high molecular polymers include addition polymers having a carboxy group in the side chain, such as JP-A-59-44615, JP-B-54-34327, JP-B-58-12577, JP-B-54- 25957, JP-A-54-92723, JP-A-59-53836 and JP-A-59-71048, that is, a methacrylic acid copolymer, an acrylic acid copolymer, Itaconic acid copolymer, crotonic acid copolymer, maleic acid copolymer, partially esterified maleic acid copolymer and the like can be mentioned.
[0089]
As the polymer binder, an acidic cellulose derivative having a carboxy group in the side chain can also be used. Further, a product obtained by adding a cyclic acid anhydride to an addition polymer having a hydroxy group is also useful.
[0090]
Among them, [benzyl (meth) acrylate / (meth) acrylic acid / other addition-polymerizable vinyl monomer as required] copolymer and [allyl (meth) acrylate (meth) acrylic acid / other addition as required Polymerizable vinyl monomer] is preferred.
In addition, polyvinyl pyrrolidone, polyethylene oxide and the like are useful as the water-soluble organic polymer.
Further, in order to improve the strength of the cured film, alcohol-soluble polyamide, polyether of 2,2-bis- (4-hydroxyphenyl) -propane and epichlorohydrin; JP 7-120040, JP Nos. 7-120041, 7-120042, 8-12424, JP 63-287944, JP 63-287947, JP 1-271741 and JP 11-352691 Polyurethane resins described in the publication are also useful.
[0091]
In these organic polymer polymers, the strength of the cured film can be improved by introducing a radical reactive group into the side chain. Functional groups that can undergo addition polymerization reaction include ethylenically unsaturated bond groups, amino groups, epoxy groups, etc., and functional groups that can be converted to radicals by light irradiation, such as mercapto groups, thiol groups, halogen atoms, triazine structures, onium salt structures. And the like include a carboxy group, an imide group and the like as polar groups. As the functional group capable of addition polymerization reaction, an ethylenically unsaturated bond group such as an acryl group, a methacryl group, an allyl group, or a styryl group is particularly preferable, but an amino group, a hydroxy group, a phosphonic acid group, a phosphoric acid group, or a carbamoyl group. Also useful are functional groups selected from the group consisting of isocyanate groups, ureido groups, ureylene groups, sulfo groups and ammonio groups.
[0092]
In order to maintain the developability of the photopolymerizable composition, the polymer binder in the present invention preferably has an appropriate molecular weight and acid value. The weight average molecular weight is preferably 5,000 to 300,000, and the acid value is preferably 20 to 200.
[0093]
The polymer binder can be mixed in an arbitrary amount in the photopolymerizable composition, but is preferably 10 to 90% by mass, and preferably 30 to 80% by mass with respect to the total solid content of the photopolymerizable composition. % Is more preferred. When it exceeds 90 mass%, it is not preferable at points, such as image intensity formed.
The mass ratio between the ethylenically unsaturated bond-containing compound and the polymer binder is preferably 1/9 to 9/1, more preferably 2/8 to 8/2, and 3/7. More preferably, it is ˜7 / 3.
[0094]
In the present invention, the photopolymerizable composition may contain an infrared absorber. Specific examples of the infrared absorber include various infrared absorbers used in a thermal positive type thermosensitive layer described later.
[0095]
In addition to the above essential components, the photopolymerizable composition is prohibited from a small amount of thermal polymerization in order to prevent unnecessary thermal polymerization of the ethylenically unsaturated bond-containing compound during the production or storage of the photopolymerizable composition. It is preferable to contain an agent.
Suitable thermal polymerization inhibitors include hydroquinone, p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4-thiobis (3-methyl-6-t-butylphenol ), 2,2′-methylenebis (4-methyl-6-tert-butylphenol), N-nitrosophenylhydroxylamine cerium salt, N-nitrosophenylhydroxylamine aluminum salt, and the like.
The content of the thermal polymerization inhibitor is preferably about 0.01 to about 5% by mass with respect to the total solid content of the photopolymerizable composition.
[0096]
In addition, the photopolymerizable composition may contain a higher fatty acid derivative such as behenic acid or behenic acid amide, if necessary, in order to prevent polymerization inhibition by oxygen, and in the process of drying after coating. It may be unevenly distributed on the surface of the photosensitive layer. The content of the higher fatty acid derivative or the like is preferably about 0.5 to about 10% by mass with respect to the total solid content of the photopolymerizable composition.
[0097]
Further, the photopolymerizable composition may contain a colorant for the purpose of coloring the photosensitive layer. Examples of the colorant include dyes and pigments (for example, phthalocyanine pigments, azo pigments, carbon black) used in the above-described conventional positive type and conventional negative type photosensitive layers. The content of the colorant is preferably about 0.5 to about 20% by mass with respect to the total solid content of the photopolymerizable composition.
The photopolymerizable composition may contain an additive such as an inorganic filler; a plasticizer such as dioctyl phthalate, dimethyl phthalate, or tricresyl phosphate in order to improve the physical properties of the cured film. These contents are preferably 10% by mass or less based on the total solid content of the photopolymerizable composition.
[0098]
When the photopolymerizable composition is applied onto an adhesive layer described later, it is dissolved in various solvents and used. Examples of the solvent include the same solvents as those exemplified as the solvent used in the above-described conventional negative type photosensitive layer. These solvents can be used alone or in combination. The concentration (solid content) of the coating solution is preferably 1 to 50% by mass.
The photopolymerizable composition can contain a surfactant in order to improve the coating surface quality.
[0099]
The coating amount (solid content) of the photosensitive layer is about 0.1 to about 10 g / m²Preferably, 0.3 to 5 g / m²More preferably, 0.5-3 g / m²More preferably.
[0100]
(Oxygen barrier protective layer)
Usually, an oxygen-blocking protective layer is provided on the photosensitive layer in order to prevent an oxygen polymerization inhibiting action.
Examples of the water-soluble vinyl polymer contained in the oxygen-blocking protective layer include polyvinyl alcohol, partial esters thereof, ethers, acetals, and substantial amounts of unsubstituted vinyl alcohol units that make them necessary water-soluble. And a copolymer thereof.
Examples of polyvinyl alcohol include those that are 71-100% hydrolyzed and have a degree of polymerization of 300-2400.
Other useful polymers include polyvinyl pyrrolidone, gelatin, and gum arabic.
These may be used alone or in combination of two or more.
[0101]
The solvent used for applying the oxygen-blocking protective layer is preferably pure water, but alcohols such as methanol and ethanol; ketones such as acetone and methyl ethyl ketone may be mixed with pure water.
The concentration (solid content) of the coating solution is preferably 1 to 20% by mass.
A known additive such as a surfactant for improving the coating property and a water-soluble plasticizer for improving the physical properties of the film may be added to the oxygen-blocking protective layer.
The coating amount of the oxygen barrier protective layer is about 0.1 to about 15 g / m in terms of mass after drying.²Preferably, about 1.0 to about 5.0 g / m²It is more preferable that
[0102]
(Adhesive layer)
It is one of preferred embodiments of the present invention to provide the following adhesive layer as the lower layer of the photopolymer type photosensitive layer.
The adhesive layer contains a silicon compound having a functional group that can cause an addition reaction by a radical such as an alkenyl group or an alkynyl group (hereinafter referred to as “addition-reactive functional group”).
The adhesive layer is coated using an organic silicon compound (hereinafter referred to as “organic silicon compound (S)”) having an addition-reactive functional group and a hydrolyzable functional group such as an alkoxy group. By treating the surface of the support for use, the hydrolyzable functional group and the metal, metal oxide, hydroxide, hydroxy group, silanol group formed by the chemical conversion treatment of the support, etc. Can be reacted to form a covalent bond between the organosilicon compound and the support surface, and the addition-reactive functional group can be attached to the support surface or planted. Specific examples of the organic silicon compound (S) include trialkoxysilyl compounds (hereinafter referred to as “organic silicon compounds (S-1)”) and tetraalkoxysilane compounds (hereinafter referred to as “organic silicon compounds (S-2)”). ) And the like.
[0103]
As the organic silicon compound (S), from the viewpoint of improving stain resistance when a lithographic printing plate is used, a mixture of the organic silicon compound (S-1) and the organic silicon compound (S-2) is used. preferable.
[0104]
The above-mentioned organosilicon compound is applied to a lithographic printing plate support in a state where at least one of the 1-4 addition-reactive functional groups bonded to the central Si atom remains unhydrolyzed. . When the organosilicon compound is coated on the lithographic printing plate support, it may be used as it is, or may be diluted with an appropriate solvent.
Water and / or a catalyst can be added to bind the organosilicon compound more firmly on the lithographic printing plate support. Preferred examples of the solvent include alcohols such as methanol, ethanol, propanol, isopropanol, ethylene glycol, and hexylene glycol. Examples of the catalyst include acids such as hydrochloric acid, acetic acid, phosphoric acid, and sulfuric acid; ammonia, tetramethyl A base such as ammonium hydroxide is preferably exemplified.
[0105]
The amount of the addition-reactive functional group on the lithographic printing plate support varies depending on the kind of the addition-reactive functional group to be bonded, but is usually 10 nm.²The number is 0.01 to 1000 per unit, preferably 0.05 to 200, and more preferably 0.1 to 50. Additive functional group amount is 10nm²When the number is less than 0.01 per unit, it is difficult to obtain sufficient photoadhesive strength. 10nm thick by recoating the organosilicon compound thickly²The amount of the addition-reactive functional group can be substantially increased as much as possible, but the amount of the addition-reactive functional group that can be present in the state exposed on the outermost surface is 10 nm.²Since there are at most 10 pieces per piece, it is useless even if it is applied too thickly. In order to prevent the amount of the addition-reactive functional group from being excessively large and insufficient hydrophilicity of the non-image area,²The amount of the addition-reactive functional group is preferably 1000 or less.
[0106]
Specifically, the mixing molar ratio of the organosilicon compound (S-2) to the organosilicon compound (S-1) is preferably 0.05 to 500, more preferably 0.2 to 200. 1 to 100 is more preferable. Further, within the above range, the hydrophilicity of the non-image area increases as the amount of the hydrophilic group derived from the organic silicon compound (S-2) is increased. However, even when the density of the hydrophilic group is low, the density of the hydrophilic group can be improved by hydrophilizing the addition-reactive functional group.
[0107]
Examples of the introduction of the addition-reactive functional group on the surface of the lithographic printing plate support and the specific embodiment of the organosilane compound include the contents described in JP-A-7-159983 and 8-320551. Can be used.
[0108]
In order to avoid uneven distribution of the adhesive layer used in the present invention, it is preferable to adjust the concentration by adding a solvent before applying these treatment liquids to the support.
As the solvent used for this purpose, alcohols, particularly methanol, are suitable, but other solvents, organic compounds, inorganic additives, surfactants and the like can also be added. Examples of the other solvent include those exemplified as the solvent used in the above-described conventional negative type photosensitive layer.
Examples of organic compounds that can be added include epoxy resins, acrylic resins, butyral resins, urethane resins, novolac resins, pyrogallol-acetone resins, polyvinyl pyrrolidone, polyvinyl alcohol, polyvinyl methyl ether, and polypropylene glycol.
Examples of the inorganic additive include colloidal silica and colloidal alumina.
[0109]
Various methods such as brush coating, dip coating, atomizing, spin coating, doctor blade coating, etc. can be used as the method for applying the liquid composition (organic silicon compound or a solution or sol solution thereof) used in the present invention. It is determined in consideration of the required film thickness.
[0110]
The above-mentioned adhesive layer containing a silicon compound having an addition-reactive functional group is not only a photopolymer type, but also a conventional positive type, a conventional negative type, a thermal positive type, a thermal negative type, and an unprocessed type image recording layer. Can also be provided.
[0111]
<Thermal positive type>
(Thermosensitive layer)
The thermal positive type heat-sensitive layer used in the present invention contains an alkali-soluble polymer compound and an infrared absorber. Here, the alkali-soluble polymer compound includes a homopolymer containing an acidic group in the main chain and / or side chain in the polymer, a copolymer thereof, and a mixture thereof. Therefore, the thermal positive type heat-sensitive layer has a property of dissolving when contacted with an alkali developer.
As the alkali-soluble polymer compound, one having at least one of the following acidic groups (1) to (6) in the main chain and / or side chain of the polymer is soluble in an alkali developer. preferable.
[0112]
(1) Phenolic hydroxy group (—Ar—OH)
(2) Sulfonamide group (—SO₂NH-R)
(3) Substituted sulfonamide acid group (—SO₂NHCOR, -SO₂NHSO₂R, -CONHSO₂R) (hereinafter referred to as “active imide group”)
(4) Carboxy group (—CO₂H)
(5) Sulfo group (—SO_ThreeH)
(6) Phosphate group (-OPO_ThreeH₂)
[0113]
In the above (1) to (6), Ar represents a divalent aryl linking group which may have a substituent. R represents a hydrocarbon group which may have a substituent.
[0114]
Among the alkali-soluble polymer compounds having an acidic group selected from the above (1) to (6), (1) an alkali-soluble polymer compound having a phenol group, (2) a sulfonamide group, and (3) an active imide group. In particular, an alkali-soluble polymer compound having (1) a phenol group or (2) a sulfonamide group is most preferable from the viewpoint of sufficiently ensuring solubility in an alkali developer and film strength.
[0115]
Next, typical examples of polymerization components of these alkali-soluble polymer compounds will be described.
(1) The polymerizable monomer having a phenolic hydroxy group includes a polymerizable monomer composed of a low molecular compound having at least one phenolic hydroxy group and one polymerizable unsaturated bond, for example, phenolic Examples include acrylamides and methacrylamides having a hydroxy group; derivatives such as acrylic acid esters, methacrylic acid esters, and hydroxystyrene.
These monomers having a phenolic hydroxy group may be used in combination of two or more.
[0116]
(2) As a polymerizable monomer having a sulfonamide group, a sulfonamide group (—NH—SO) in which at least one hydrogen atom is bonded to a nitrogen atom in one molecule.₂-) And a polymerizable monomer comprising a low-molecular compound having at least one polymerizable unsaturated bond, such as an acryloyl group, an allyl group or a vinyloxy group, a mono-substituted aminosulfonyl group or a substituted sulfonylimino A low molecular weight compound having a group is preferred. Examples of such compounds include compounds represented by general formulas (I) to (V) described in JP-A-8-123029.
Among these compounds, as the polymerizable monomer having a sulfonamide group, specifically, m-aminosulfonylphenyl methacrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p-aminosulfonylphenyl) acrylamide Etc. can be used suitably.
[0117]
(3) As the polymerizable monomer having an active imide group, those having an active imide group described in JP-A No. 11-84657 are preferably contained in the molecule, and can be polymerized with the active imide group in one molecule. And polymerizable monomers composed of low molecular compounds each having one or more such unsaturated bonds.
As the polymerizable monomer having an active imide group, specifically, N- (p-toluenesulfonyl) methacrylamide, N- (p-toluenesulfonyl) acrylamide and the like can be preferably used.
[0118]
Examples of the alkali-soluble polymer compound having (4) a carboxy group, (5) a sulfo group and / or (6) a phosphoric acid group include, for example, a non-polymerizable compound with these acidic groups in one molecule. The polymer which has the minimum structural unit derived from the compound which has one or more each as a saturated group as a main structural component can be mentioned.
[0119]
The minimum structural unit having an acidic group selected from the above (1) to (6) that constitutes the alkali-soluble polymer compound used in the thermal positive-type heat-sensitive layer is not necessarily limited to one kind, and is identical. Two or more minimum structural units having an acidic group, or two or more minimum structural units having different acidic groups copolymerized may be used.
As a copolymerization method, a conventionally known graft copolymerization method, block copolymerization method, random copolymerization method, or the like can be used.
[0120]
In the copolymer, the compound having an acidic group selected from the above (1) to (6) to be copolymerized is preferably contained in an amount of 10 mol% or more, and contained in an amount of 20 mol% or more. More preferably. If it is less than 10 mol%, the development latitude tends to be insufficiently improved.
[0121]
Further, when a copolymer is formed by copolymerizing a compound, as the compound, other compounds not containing the acidic groups (1) to (6) can be used.
[0122]
As the alkali-soluble polymer compound, novolak resins having a phenolic hydroxy group described in U.S. Pat. No. 4,123,279 and the like in terms of excellent image forming property by exposure with an infrared laser or the like, Pyrogallol acetone resin is preferred.
[0123]
The weight average molecular weight of the alkali-soluble polymer compound is preferably 500 or more, and more preferably 1,000 to 700,000. The number average molecular weight is preferably 500 or more, and more preferably 750 to 650,000. The dispersity (weight average molecular weight / number average molecular weight) is preferably 1.1 to 10.
[0124]
The alkali-soluble polymer compound may be used alone or in combination of two or more, and the total content thereof is 1 to 90% by mass with respect to the total solid content of the heat-sensitive layer. Is preferable, it is more preferable that it is 2-70 mass%, and it is still more preferable that it is 2-50 mass%. If the content is less than 1% by mass, the durability tends to deteriorate, and if it exceeds 90% by mass, the sensitivity and image formability tend to decrease, such being undesirable.
[0125]
The infrared absorbent used in the present invention is a substance that generates heat by absorbing light. The infrared absorber enables the interaction energy of the exposed area of the heat sensitive layer to be efficiently released by converting the exposure energy into heat.
The infrared absorber in the present invention is preferably a pigment or dye having a light absorption region in the infrared region having a wavelength of 700 to 1200 nm from the viewpoint of recording sensitivity.
[0126]
Examples of the pigment include commercially available pigments, Color Index (CI) Handbook, “Latest Pigment Handbook” (edited by the Japan Pigment Technology Association, published in 1977), “Latest Pigment Applied Technology” (published by CMC, published in 1986). And pigments described in “Printing Ink Technology” published by CMC (published in 1984) can be used.
[0127]
Examples of the pigment include black pigment, yellow pigment, orange pigment, brown pigment, red pigment, purple pigment, blue pigment, green pigment, fluorescent pigment, metal powder pigment, and polymer-bonded dye. Specifically, insoluble azo pigments, azo lake pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, anthraquinone pigments, perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments A quinophthalone pigment, a dyed lake pigment, an azine pigment, a nitroso pigment, a nitro pigment, a natural pigment, a fluorescent pigment, an inorganic pigment, or carbon black can be used.
[0128]
These pigments may be used without surface treatment, or may be used after conventionally known surface treatment.
[0129]
The particle size of the pigment is preferably in the range of 0.01 to 10 μm, more preferably in the range of 0.05 to 1 μm, and still more preferably in the range of 0.1 to 1 μm. The above range is preferable in terms of the stability of the pigment dispersion in the heat-sensitive layer coating solution and the uniformity of the heat-sensitive layer.
[0130]
As a method for dispersing the pigment, for example, a known dispersion technique used in ink production, toner production, or the like described in “Latest Pigment Application Technology” (CMC Publishing, 1986) or the like can be used.
[0131]
Examples of the dye include commercially available dyes and known dyes described in literature (for example, “Dye Handbook”, published by Kodansha (1986), “Dye Handbook”, edited by the Society of Synthetic Organic Chemistry, published in 1970). Available. Specifically, azo dyes, metal complex salt azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, azurenium dyes, quinoneimine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, metal metal complexes A dye such as a dithiol metal complex or a metal-containing phthalocyanine can be used.
[0132]
In the present invention, among these pigments or dyes, those that absorb infrared light or near infrared light are particularly preferred because they are suitable for use with lasers that emit infrared light or near infrared light.
[0133]
As such a pigment that absorbs infrared light or near infrared light, phthalocyanine (including metal-containing phthalocyanine) and carbon black are preferably used. Examples of dyes that absorb infrared light or near infrared light include cyanine dyes, merocyanine dyes, iminium dyes, oxonol dyes, pyrylium (including thiopyrylium, serenapyrylium, ternapyrylium) dyes, naphthoquinone dyes, Examples thereof include squarylium dyes, phthalocyanine (including metal-containing phthalocyanine) dyes, organometallic complexes (metal complex compounds with dithiol, diamine, etc.), and the like. Specifically, for example, compounds described in paragraphs [0020] to [0021] of JP-A-7-285275 and “Electronics-related dyes—current status and future prospects”, Chapter 16 Examples thereof include compounds described in publicly known materials such as CMC (1998).
[0134]
Further, as another preferred example of the dye, a near-infrared absorbing dye described as formula (I) or (II) in US Pat. No. 4,756,993, JP-A No. 2000-267265 An infrared absorbing dye that is soluble in an alkaline aqueous solution described in JP-A No. 11-309952, an infrared absorbing dye containing a functional group that changes hydrophilicity by heat, and JP-A 2000-2000 Examples thereof include polymethine dyes described in JP-A Nos. 160131, 2000-330271, 2001-117216, and 2001-174980, and phthalocyanine dyes described in JP-A No. 2000-352817. However, the pigment | dye as an infrared absorber used for this invention is not limited to these.
[0135]
The content of these pigments or dyes is preferably 0.01 to 50% by mass, more preferably 0.01 to 30% by mass, and still more preferably 0.1 to 10% by mass, based on the total solid content of the heat-sensitive layer. %, In the case of dyes, particularly preferably 0.5 to 10% by mass, and in the case of pigments, particularly preferably 1 to 10% by mass. When the pigment or dye content is less than 0.01% by mass, the sensitivity may be low, and when it exceeds 50% by mass, the uniformity of the heat-sensitive layer is lost and the durability of the heat-sensitive layer is deteriorated. There is.
[0136]
These dyes or pigments may be added to the same layer as other components, or a separate layer may be provided and added thereto. In the case of another layer, it is preferably added to a layer adjacent to a layer containing a substance that is thermally decomposable and substantially reduces the solubility of the alkali-soluble polymer compound in a state where it does not decompose.
[0137]
The heat-sensitive layer can further contain various additives as required. For example, in combination with a substance that is thermally decomposable and substantially reduces the solubility of the alkali-soluble polymer compound in a state where it is not decomposed, it is possible to improve the dissolution inhibition of the image area in the developer, preferable. Examples of such substances include onium salts, quinonediazides, aromatic sulfone compounds, and aromatic sulfonic acid ester compounds.
[0138]
Examples of onium salts include diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts, and arsonium salts.
Among them, preferred specific examples include those having the same contents as the compounds exemplified as the photoacid generator used in the above-described conventional positive type photosensitive layer.
[0139]
The counter ion of the onium salt is an inorganic ion or an organic ion, and specifically, those described in the above-mentioned known documents can be used.
[0140]
Suitable quinonediazides include o-quinonediazide compounds. The o-quinonediazide compound used in the present invention is a compound having at least one o-quinonediazide group, which increases alkali solubility by thermal decomposition, and compounds having various structures can be used. That is, o-quinonediazide helps the solubility of the sensitive material system by both the effect of losing the ability to suppress the dissolution of the binder due to thermal decomposition and the change of o-quinonediazide itself into an alkali-soluble substance.
[0141]
Examples of the o-quinonediazide compound used in the present invention include the same compounds as those used in the above-described conventional positive type photosensitive layer.
[0142]
The addition amount of the onium salt or the o-quinonediazide compound is preferably in the range of 1 to 50% by mass, more preferably 5 to 30% by mass, and still more preferably 10 to 30% by mass with respect to the total solid content of the heat-sensitive layer. is there.
These compounds can be used alone, but may be used as a mixture of two or more.
[0143]
As other components contained in the thermal positive type heat-sensitive layer, various components of known image recording layer materials that can be recorded with actinic radiation such as infrared rays can be appropriately selected and used.
The thermal positive type heat-sensitive layer can contain various additives as required. For example, when other onium salts, aromatic sulfone compounds, aromatic sulfonic acid ester compounds, polyfunctional amine compounds, etc. are contained, the ability to inhibit dissolution of alkali-soluble polymer compounds in a developer can be improved. preferable.
[0144]
In addition, the thermosensitive layer is used for the purpose of further improving the sensitivity, such as phenols, cyclic acid anhydrides described in US Pat. No. 4,115,128, JP-A-60-88942, and the like. Organic acids described in, for example, Kaihei 2-96755 can also be contained.
The content of cyclic acid anhydrides, phenols and organic acids is preferably 0.05 to 20% by mass, preferably 0.1 to 15% by mass, based on the total solid content of the layer to be added. Is more preferable, and it is especially preferable that it is 0.1-10 mass%.
[0145]
In addition to these, epoxy compounds, vinyl ethers, phenol compounds having a hydroxymethyl group and phenol compounds having an alkoxymethyl group described in JP-A-8-276558, JP-A-62-251740, and Nonionic surfactants as described in JP-A-3-208514, amphoteric surfactants as described in JP-A-59-121044 and JP-A-4-13149, European patents Siloxane compounds as described in Japanese Patent Application Publication No. 950,517, and fluorine-containing monomer copolymers as described in JP-A Nos. 62-170950 and 11-288093 The alkaline dissolution inhibiting action described in JP-A-11-160860 Crosslinking compound which, plasticizers (e.g., polyethylene glycol; carboxylic acids, alkyl esters such as phosphoric acid) and the like can be contained as appropriate depending on the purpose. These additives can be arbitrarily added within a range that does not deteriorate other performances of the photosensitive layer. Specifically, it is preferably 0.01 to 15% by mass and more preferably 0.1 to 5% by mass with respect to the total solid content of the layer to be added.
[0146]
The heat-sensitive layer can contain a print-out agent for obtaining a visible image immediately after heating by exposure, and a dye or pigment as an image colorant.
Examples of the printing-out agent include a combination of a compound that releases an acid by heating by exposure (photoacid releasing agent) and an organic dye that can form a salt. Specifically, JP-A-50-36209, JP-A-53-8128, JP-A-53-36223, JP-A-54-74728, JP-A-60-3626, JP-A-61- And the compounds described in JP-A Nos. 143748, 61-151644 and 63-58440, and the like.
[0147]
As the image colorant, other dyes can be used in addition to the aforementioned salt-forming organic dyes. Examples of suitable dyes including salt-forming organic dyes include oil-soluble dyes and basic dyes. The dyes described in JP-A-62-293247 and JP-A-5-313359 are particularly preferred.
The addition amount of these dyes is preferably 0.01 to 10% by mass, more preferably 0.1 to 3% by mass, based on the total solid content of the layer to be added.
[0148]
The heat-sensitive layer of the present invention may be a single layer or a two-layer structure as described in JP-A-11-218914.
[0149]
The heat-sensitive layer can be usually produced by applying a heat-sensitive layer coating solution obtained by dissolving each of the above components in a solvent onto a lithographic printing plate support.
Examples of the solvent used here include, but are not limited to, the same solvents as those used in the above-described conventional negative type photosensitive layer. These solvents are used alone or in combination.
The concentration of the above components (total solid content including additives) in the solvent is preferably 1 to 50% by mass.
As a coating method, various methods similar to those in the case of the conventional positive type photosensitive layer described above can be used.
[0150]
In addition, the coating amount (solid content) of the heat-sensitive layer varies depending on the use, but is generally 0.5 to 5.0 g / m.²Is preferred. When the coating amount is less than the above range, the apparent sensitivity increases, but the film characteristics of the heat-sensitive layer that performs the function of image recording deteriorate.
[0151]
(Undercoat layer)
An undercoat layer can be provided between the thermal positive type heat-sensitive layer and the support, if necessary.
As the component contained in the undercoat layer, various organic compounds can be mentioned. For example, carboxymethyl cellulose; dextrin; gum arabic; phosphonic acids having an amino group such as 2-aminoethylphosphonic acid, phenylphosphonic acid, naphthylphosphonic acid, alkylphosphonic acid, glycerophosphonic acid, which may have a substituent, Organic phosphonic acids such as methylene diphosphonic acid and ethylene diphosphonic acid; organic phosphoric acids such as phenyl phosphoric acid, naphthyl phosphoric acid, alkyl phosphoric acid and glycerophosphoric acid which may have a substituent; Organic phosphinic acids such as phenylphosphinic acid, naphthylphosphinic acid, alkylphosphinic acid and glycerophosphinic acid; amino acids such as glycine and β-alanine; hydrochlorides of amines having a hydroxy group such as hydrochloride of triethanolamine, etc. Is mentioned. These may be used alone or in combination of two or more.
[0152]
Further, as the undercoat layer, an intermediate layer containing a polymer compound having a component having an acid group and a component having an onium group described in JP-A-2000-105462 is also preferably used. . By providing this intermediate layer, it is possible to obtain a large number of clear printed matter having sufficient alkali developability and without causing deterioration of stain resistance and image strength during printing.
This undercoat layer can be provided not only in the thermal positive type but also in each of the conventional positive type, conventional negative type, photopolymer type, thermal negative type and non-process type image recording layers.
[0153]
The undercoat layer can be provided by the following method. That is, a method in which a solution obtained by dissolving the above organic compound in water or an organic solvent such as methanol, ethanol, methyl ethyl ketone, or a mixed solvent thereof is applied on a lithographic printing plate support and dried, and water or methanol, In this method, an aluminum plate is immersed in an organic solvent such as ethanol or methyl ethyl ketone or a mixed solvent thereof so that the compound is adsorbed, washed with water, and then dried.
In the former method, a solution having a concentration of preferably 0.005 to 10% by mass of the organic compound can be applied by various methods. In the latter method, the concentration of the solution is preferably 0.01 to 20% by mass, more preferably 0.05 to 5% by mass, and the immersion temperature is preferably 20 to 90 ° C., more preferably 25 to 50%. The immersion time is preferably 0.1 second to 20 minutes, more preferably 2 seconds to 1 minute.
The solution used in the above method can be adjusted to a pH range of 1 to 12 with a basic substance such as ammonia, triethylamine, potassium hydroxide, or an acidic substance such as hydrochloric acid or phosphoric acid. Further, a yellow dye may be contained for improving the tone reproducibility of the image recording material.
The coating amount of the undercoat layer is 2 to 200 mg / m²Appropriately, 5 to 100 mg / m²Is preferred. Covering amount is 2mg / m²If it is less than 1, sufficient printing durability may not be obtained. 200 mg / m²It is the same even if it exceeds.
[0154]
<Thermal negative type>
(Thermosensitive layer)
Any thermal negative-type heat-sensitive layer may be used as long as it contains an infrared absorber and the negative-type heat-sensitive layer forms an image part by curing the infrared laser irradiation part.
As one of such thermal negative type heat-sensitive layers, a photopolymerization layer is preferably exemplified. The photopolymerization layer contains (A) an infrared absorber, (B) a radical generator (radical polymerization initiator), and a radically polymerizable compound (C) that is cured by causing a polymerization reaction with the generated radicals. Preferably it further contains (D) a binder polymer.
In the photopolymerization layer, infrared rays absorbed by the infrared absorber are converted into heat, and the generated heat decomposes radical polymerization initiators such as onium salts to generate radicals. The radically polymerizable compound is selected from compounds having at least one ethylenically unsaturated double bond and having at least one terminal ethylenically unsaturated bond, preferably two or more, and polymerizes in a chain manner by the generated radicals. A reaction takes place and cures.
[0155]
In addition to the photopolymerization layer, an acid cross-linking layer is preferably used as one of the thermal negative type heat-sensitive layers. The acid cross-linking layer comprises (E) a compound that generates an acid by light or heat (hereinafter referred to as “acid generator”) and (F) a compound that cross-links by the generated acid (hereinafter referred to as “cross-linking agent”). And (G) an alkali-soluble polymer compound that can react with a crosslinking agent in the presence of an acid to form a layer containing these.
In the acid cross-linking layer, the acid generated by decomposition of the acid generator by light irradiation or heating promotes the action of the cross-linking agent, and strong cross-linking between the cross-linking agents or between the cross-linking agent and the binder polymer. A structure is formed, which reduces alkali solubility and makes it insoluble in the developer. At this time, in order to efficiently use the energy of the infrared laser, (A) an infrared absorber is blended in the acid crosslinking layer.
[0156]
Each compound used in the photopolymerization layer is described below.
(A) Infrared absorber
The infrared absorber has a function of converting absorbed infrared rays into heat. The heat generated by the infrared absorber decomposes the radical generator and the acid generator to generate radicals and acids. The infrared absorber used in the present invention is a dye or pigment having an absorption maximum at a wavelength of 760 to 1200 nm.
[0157]
Examples of the dye include the dyes exemplified above as the infrared absorber contained in the thermal positive type heat-sensitive layer.
Among these dyes, particularly preferred are oxonol dyes, cyanine dyes, squarylium dyes, pyrylium salts, and organometallic complexes (phthalocyanine metal salts, dithiolate metal complexes, etc.). Specifically, it is described in JP-A-11-119421, JP-A-11-95421, JP-A-2000-267265, 2000-338651, 2000-347393, and 2001-125260. Infrared absorbing dyes.
[0158]
Examples of the pigment include commercially available pigments, Color Index (CI) Handbook, “Latest Pigment Handbook” (edited by the Japan Pigment Technology Association, published in 1977), “Latest Pigment Applied Technology” (published by CMC, published in 1986). And pigments described in “Printing Ink Technology” published by CMC (published in 1984) can be used. Specifically, the pigment illustrated above is mentioned as an infrared absorber contained in a thermal positive type thermosensitive layer, for example.
The details of these pigments are the same as those used in the thermal positive type heat-sensitive layer.
[0159]
The content of the dye or pigment is preferably 0.01 to 50% by mass, more preferably 0.1 to 10% by mass, and more preferably 0.1 to 10% by mass, based on the total solid content of the heat-sensitive layer. Is more preferably 0.5 to 10% by mass, and in the case of a pigment, it is more preferably 1.0 to 10% by mass.
When the content is less than 0.01% by mass, the sensitivity may be lowered. When the content exceeds 50% by mass, stains may occur in the non-image area when a lithographic printing plate is used.
[0160]
(B) Radical generator
The radical generator is a compound that generates radicals by thermal energy and initiates and accelerates polymerization of a compound having a polymerizable unsaturated group. As the radical generator, a conventionally known thermal polymerization initiator, a compound having a bond with a small bond dissociation energy, and the like can be appropriately selected and used.
For example, onium salt compounds (specifically, onium salt compounds exemplified as the photoacid generator used in the conventional positive type photosensitive layer described above), carbonyl compounds, organic peroxides, organic halogen compounds, azo-based polymerization Examples include initiators, azide compounds, titanocene compounds, hexaarylbiimidazole compounds, organic borate compounds, and disulfone compounds. Specific examples include those exemplified as the photopolymerization initiator used in the above-described photopolymer type photosensitive layer.
[0161]
An organic boron complex can also be used as the radical generator. Examples of the organic boron complex include organic boron sulfonium complexes or organic boron oxosulfonium complexes described in JP-A-6-157623, JP-A-6-175564, and JP-A-6-175561, and JP-A-6 Organoboron iodonium complexes described in JP-A-175554 and JP-A-6-175553, organoboron phosphonium complexes described in JP-A-9-188710, JP-A-6-348011, JP-A-7- Examples thereof include organoboron transition metal coordination complexes described in JP-A-128785, JP-A-7-140589, JP-A-7-306527, JP-A-7-292014, and the like.
[0162]
Among these radical generators, onium salt compounds are particularly preferable.
Specific examples of onium salt compounds that can be suitably used in the present invention include those described in paragraph numbers [0030] to [0033] of JP-A No. 2001-133969.
The onium salt compound used in the present invention preferably has a maximum absorption wavelength of 400 nm or less, and more preferably 360 nm or less. Thus, by setting the absorption wavelength in the ultraviolet region, the planographic printing plate precursor of the present invention can be handled under white light.
[0163]
The content of these radical generators is preferably 0.1 to 50% by mass, more preferably 0.5 to 30% by mass with respect to the total solid content of the heat-sensitive layer, and 1 to 20%. More preferably, it is mass%. If the content is less than 0.1% by mass, the sensitivity is lowered, and if it exceeds 50% by mass, the non-image area may be smeared during printing. These radical generators may be used alone or in combination of two or more. Moreover, these radical generators may be added to the same layer as other components, or another layer may be provided and added thereto.
[0164]
(C) Radical polymerizable compound
The radically polymerizable compound is a radically polymerizable compound having at least one ethylenically unsaturated double bond, and is selected from compounds having at least one terminal ethylenically unsaturated bond, preferably two or more. Such compound groups are widely known in the industrial field, and these can be used without any particular limitation in the present invention. These have chemical forms such as monomers, prepolymers (that is, dimers, trimers and oligomers), mixtures thereof, and copolymers thereof.
[0165]
Examples of monomers and copolymers thereof include unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid), esters thereof, and amides. Preferably, esters of unsaturated carboxylic acid and aliphatic polyhydric alcohol compound and amides of unsaturated carboxylic acid and aliphatic polyamine compound are used.
In addition, an addition reaction product of a unsaturated carboxylic acid ester or amide having a nucleophilic substituent such as a hydroxy group, an amino group or a mercapto group with a monofunctional or polyfunctional isocyanate or epoxy, monofunctional or polyfunctional A dehydration condensation reaction product with a functional carboxylic acid is also preferably used. Further, an addition reaction product of an unsaturated carboxylic acid ester or amide having an electrophilic substituent such as an isocyanate group or an epoxy group with a monofunctional or polyfunctional alcohol, amine or thiol, and further a halogen group A substitution reaction product of an unsaturated carboxylic acid ester or amide having a leaving substituent such as a tosyloxy group and a monofunctional or polyfunctional alcohol, amine or thiol is also suitable. As another example, it is also possible to use a group of compounds substituted with unsaturated phosphonic acid, styrene or the like instead of the unsaturated carboxylic acid.
[0166]
More specific embodiments include the same contents as exemplified above as the ethylenically unsaturated bond-containing compound contained in the photopolymer type photosensitive layer.
[0167]
For these radically polymerizable compounds, details on how to use them, such as what structure to use, whether they are used singly or in combination of two or more, and how much is added, are in the performance design of the final recording material. In addition, it can be set arbitrarily. For example, it is selected from the following viewpoints.
From the viewpoint of sensitivity, a structure having a large unsaturated group content per molecule is preferable, and in many cases, a bifunctional or higher functionality is preferable. Further, in order to increase the strength of the image portion, that is, the cured film, those having three or more functionalities are preferable, and furthermore, compounds having different functional numbers or different polymerizable groups (for example, acrylic ester compounds, methacrylic acid Ester compounds, styrene compounds and the like: For example, JP-B-49-43191, JP-A-52-30490, JP-A-46-43946, JP-B-1-40337, JP-A-1-40336, JP-A-2-25493, A method of adjusting both photosensitivity and strength is also effective by using a combination of JP-A-61-22048, Japanese Journal of Adhesion, Vol. 20 (No. 7) (1984), etc. . A compound having a large molecular weight or a compound having high hydrophobicity is excellent in sensitivity and film strength, but may not be preferable in terms of development speed and precipitation in a developer. In addition, the selection and use method of the radical polymerization compound is also an important factor for the compatibility and dispersibility with other components in the heat-sensitive layer (for example, binder polymer, initiator, colorant, etc.). The compatibility may be improved by using a low-purity compound or using a combination of two or more compounds. In addition, a specific structure may be selected for the purpose of improving the adhesion of the support, overcoat layer and the like. As for the compounding ratio of the radically polymerizable compound in the image recording layer, a larger amount is advantageous in terms of sensitivity. However, when the amount is too large, undesirable phase separation may occur or the production process due to the adhesiveness of the image recording layer may occur. Problems (for example, transfer of recording layer components, manufacturing defects due to adhesion) and precipitation from the developer may occur.
[0168]
From these viewpoints, the blending ratio of the radical polymerizable compound is preferably 5 to 80% by mass and more preferably 20 to 75% by mass with respect to the total solid content of the heat-sensitive layer in many cases. . Moreover, these may be used independently and may use 2 or more types together. In addition, the usage of the radical polymerizable compound can be arbitrarily selected from the viewpoint of polymerization inhibition with respect to oxygen, resolution, fogging, refractive index change, surface tackiness, etc. Depending on the case, a layer configuration such as undercoating or topcoating and a coating method may be performed.
[0169]
(D) Binder polymer
In the present invention, it is preferable to further use a binder polymer. It is preferable to use a linear organic polymer as the binder polymer. Any linear organic polymer may be used. Preferably, a linear organic polymer that is soluble or swellable in water or weak alkaline water is selected to enable water development or weak alkaline water development. Examples of such linear organic polymers include radical polymers having a carboxy group in the side chain, such as JP-A-59-44615, JP-B-54-34327, JP-B-58-12777, and JP-B-54-25957. , JP-A-54-92723, JP-A-59-53836, JP-A-59-71048, ie, methacrylic acid copolymer, acrylic acid copolymer, itacon Examples include acid copolymers, crotonic acid copolymers, maleic acid copolymers, and partially esterified maleic acid copolymers. Similarly, an acidic cellulose derivative having a carboxy group in the side chain can be mentioned. In addition, those obtained by adding a cyclic acid anhydride to a polymer having a hydroxy group are useful.
[0170]
Of these, a (meth) acrylic resin having a benzyl group or an allyl group and a carboxy group in the side chain is particularly preferable because of its excellent balance of film strength, sensitivity, and developability.
[0171]
In addition, Japanese Patent Publication No. 7-2004, Japanese Patent Publication No. 7-120041, Japanese Patent Publication No. 7-120042, Japanese Patent Publication No. 8-12424, Japanese Patent Laid-Open No. 63-287944, Japanese Patent Laid-Open No. 63-287947, Japanese Patent Laid-Open No. Urethane-based binder polymers containing acid groups described in Japanese Patent Nos. 271741 and 11-352691 are advantageous in terms of printing durability and suitability for low exposure because of their excellent strength. .
[0172]
In addition, polyvinyl pyrrolidone, polyethylene oxide and the like are useful as the water-soluble linear organic polymer. In order to increase the strength of the cured film, alcohol-soluble nylon, polyether of 2,2-bis- (4-hydroxyphenyl) propane and epichlorohydrin are also useful.
[0173]
The weight average molecular weight of the linear organic polymer used in the present invention is preferably 5000 or more, more preferably 10,000 to 300,000, and the number average molecular weight is preferably 1000 or more, more preferably. Is 2000-250,000. The polydispersity (weight average molecular weight / number average molecular weight) is 1 or more, preferably 1.1 to 10.
[0174]
These linear organic polymers may be any of random polymers, block polymers, graft polymers and the like.
[0175]
The binder polymer may be used alone or in combination. The content of the binder polymer is preferably 20 to 95% by mass and more preferably 30 to 90% by mass with respect to the total solid content of the heat-sensitive layer. When the content is less than 20% by mass, the strength of the image area may be insufficient when an image is formed. On the other hand, if the content exceeds 95% by mass, an image may not be formed. Moreover, it is preferable that mass ratio of a radically polymerizable compound and a linear organic polymer is 1/9 to 7/3.
[0176]
Next, each compound used in the acid cross-linked layer will be described below.
(A) Infrared absorber
As the infrared absorber used for the acid crosslinking layer as necessary, the same infrared absorber as that described in the photopolymerization layer (A) can be used.
The content of the infrared absorber is preferably 0.01 to 50% by mass, more preferably 0.1 to 10% by mass, and more preferably a dye, based on the total solid content of the heat-sensitive layer. Is more preferably 0.5 to 10% by mass, and in the case of a pigment, it is more preferably 1.0 to 10% by mass.
When the content is less than 0.01% by mass, the sensitivity may be lowered. When the content exceeds 50% by mass, stains may occur in the non-image area when a planographic printing plate is used.
[0177]
(E) Acid generator
The acid generator refers to a compound that generates an acid when irradiated with light in a wavelength region of 200 to 500 nm or heated to 100 ° C. or higher.
Examples of the acid generator include a photo-initiator for photo-cationic polymerization, a photo-initiator for photo-radical polymerization, a photo-decoloring agent for dyes, a photo-discoloring agent, a known acid-generating agent used in a micro resist, etc. Examples include known compounds that can be thermally decomposed to generate an acid, and mixtures thereof.
Examples thereof include onium salt compounds, o-quinonediazide compounds, organic halogenated compounds, and disulfone compounds. Specific examples thereof are the same as those exemplified as the radical generator described above. Preferable embodiments of the onium salt compound include, for example, compounds described in paragraph numbers [0010] to [0035] of JP-A No. 10-39509.
Examples of the o-quinonediazide compound include the same compounds exemplified above as those used in the thermal positive type heat-sensitive layer.
[0178]
Other examples include the same organic acid / organic halides as those exemplified as the photoacid generator used in the above-described conventional positive type photosensitive layer, a photoacid generator having an o-nitrobenzyl type protecting group, Examples include compounds that generate a sulfonic acid by photolysis represented by iminosulfonate and the like; disulfone compounds; and compounds in which a group or a compound that generates these acids is introduced into the main chain or side chain of the polymer.
[0179]
Further, V.V. N. R. Pillai, Synthesis, (1), 1 (1980), A.M. Abad et al, Tetrahedron Lett. , (47) 4555 (1971), D.M. H. R. Barton et al, J.A. Chem. Soc. , (B), 329 (1970), U.S. Pat. No. 3,779,7798, European Patent 126,712, etc., can also be used compounds that generate an acid by light. .
[0180]
Among the acid generators described above, compounds described in paragraph numbers [0197] to [0222] of JP-A No. 2001-142230 are preferable.
[0181]
The content of the acid generator is preferably 0.01 to 50% by mass, more preferably 0.1 to 25% by mass, and more preferably 0.5 to 20% with respect to the total solid content of the heat-sensitive layer. More preferably, it is mass%.
If the content of the acid generator is less than 0.01% by mass, an image may not be obtained. If the content exceeds 50% by mass, a lithographic printing plate may have a non-image area during printing. Dirt may occur.
An acid generator may be used independently and may be used in combination of 2 or more type.
[0182]
(F) Crosslinking agent
The following are mentioned as a crosslinking agent.
(I) an aromatic compound substituted with a hydroxymethyl group or an alkoxymethyl group,
(Ii) a compound having an N-hydroxymethyl group, an N-alkoxymethyl group or an N-acyloxymethyl group,
(Iii) Epoxy compounds.
[0183]
Hereinafter, the compounds (i) to (iii) will be described in detail.
(I) As an aromatic compound substituted by the hydroxymethyl group or the alkoxymethyl group, the aromatic compound or heterocyclic compound poly-substituted by the hydroxymethyl group, an acetoxymethyl group, or the alkoxymethyl group is mentioned, for example. However, resinous compounds obtained by condensation polymerization of phenols and aldehydes known as resol resins under basic conditions are also included.
Of the aromatic compounds or heterocyclic compounds poly-substituted with a hydroxymethyl group or an alkoxymethyl group, compounds having a hydroxymethyl group or an alkoxymethyl group at a position adjacent to the hydroxy group are preferred.
Of the aromatic compounds or heterocyclic compounds poly-substituted with an alkoxymethyl group, compounds having an alkoxymethyl group with 18 or less carbon atoms are preferred. Specific examples include compounds represented by general formulas (8) to (11) described in paragraphs [0077] to [0083] of JP-A No. 2000-267265.
These crosslinking agents are preferable in that they have high crosslinking efficiency and can improve printing durability.
[0184]
(Ii) Examples of the compound having an N-hydroxymethyl group, an N-alkoxymethyl group or an N-acyloxymethyl group include European Patent Application Publication No. 0,133,216, West German Patent No. 3,634,671 and the same Monomer and oligomer-melamine-formaldehyde condensates and urea-formaldehyde condensates described in the specifications of US Pat. No. 3,711,264, described in EP 0,212,482 And alkoxy-substituted compounds.
Among them, for example, melamine-formaldehyde derivatives having at least two free N-hydroxymethyl groups, N-alkoxymethyl groups or N-acyloxymethyl groups are preferable, and N-alkoxymethyl derivatives are more preferable.
[0185]
(Iii) Examples of the epoxy compound include epoxy compounds such as monomers, dimers, oligomers, and polymers having one or more epoxy groups, such as a reaction product of bisphenol A and epichlorohydrin, and a low molecular weight phenol-formaldehyde resin. And the reaction product of epichlorohydrin.
In addition, there can be mentioned epoxy resins described in US Pat. No. 4,026,705 and British Patent 1,539,192.
[0186]
The content in the case of using the compounds (i) to (iii) as the crosslinking agent is preferably 5 to 80% by mass, more preferably 10 to 75% by mass, based on the total solid content of the heat-sensitive layer. Is more preferable, and it is still more preferable that it is 20-70 mass%.
When the addition amount of the crosslinking agent is less than 5% by mass, the durability of the heat-sensitive layer of the resulting image recording material may be reduced. When the addition amount exceeds 80% by mass, the stability during storage is reduced. Sometimes.
[0187]
In the present invention, a phenol derivative represented by the general formula (12) described in paragraphs [0088] to [0097] of JP-A No. 2000-267265 can also be suitably used as a crosslinking agent. .
[0188]
(G) Alkali-soluble polymer compound
Examples of the alkali-soluble polymer compound include novolak resins and polymers having a hydroxyaryl group in the side chain. Examples of the novolak resin include resins obtained by condensing phenols and aldehydes under acidic conditions.
[0189]
Among them, a novolak resin obtained from phenol and formaldehyde, a novolak resin obtained from m-cresol and formaldehyde, a novolak resin obtained from p-cresol and formaldehyde, a novolak resin obtained from o-cresol and formaldehyde, and octylphenol Novolak resin obtained from formaldehyde, novolak resin obtained from m- / p-mixed cresol and formaldehyde, phenol / cresol (m-, p-, o-, m- / p-mixed, m- / o-mixed And o- / p-mixture) and a novolak resin obtained from formaldehyde and phenol, and paraformaldehyde as a raw material, and obtained by reacting under high pressure in a sealed state without using a catalyst. Coupling rate High molecular weight novolak resins and the like are preferable.
The novolak resin preferably has a weight average molecular weight of 800 to 300,000 and a number average molecular weight of 400 to 60,000, which is selected according to the purpose.
[0190]
A polymer having a hydroxyaryl group in the side chain is also preferably used in the same manner as the novolak resin. Examples of the hydroxyaryl group include aryl groups in which one or more hydroxy groups are bonded. Examples of the aryl group include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, and the like. Among these, a phenyl group and a naphthyl group are preferable from the viewpoint of availability and physical properties.
Specific examples of the polymer having a hydroxyaryl group in the side chain include those described in detail in paragraph numbers [0130] to [0163] of JP-A No. 2001-142230.
An alkali-soluble high molecular compound may be used independently and may be used in combination of 2 or more type.
[0191]
The content of the alkali-soluble polymer compound is preferably 5 to 95% by mass, more preferably 10 to 95% by mass, and preferably 20 to 90% by mass with respect to the total solid content of the heat-sensitive layer. Is more preferable.
When the content of the alkali water-soluble resin is less than 5% by mass, the durability of the heat-sensitive layer may be deteriorated, and when it exceeds 95% by mass, an image may not be formed.
[0192]
As the acid cross-linking layer, in addition to the above, negative type image recording material containing a phenol derivative described in JP-A-8-276558, diazonium described in JP-A-7-306528 Negative recording material containing a compound, negative image using a crosslinking reaction by an acid catalyst using a polymer having a heterocyclic group having an unsaturated bond in the ring described in JP-A-10-203037 A forming material or the like can also be used.
[0193]
(H) Other ingredients
In addition to the above components, the thermal negative type heat-sensitive layer may further contain various compounds as necessary.
For example, the above-mentioned dyes and pigments having large absorption in the visible light region can be used as image colorants. These colorants are preferably added since it is easy to distinguish an image area from a non-image area after image formation. The content of the colorant is preferably 0.01 to 10% by mass with respect to the total solid content of the heat-sensitive layer.
[0194]
Further, when the thermosensitive layer is a photopolymerization layer, the photopolymerizable composition of the photopolymer type photosensitive layer described above is used to prevent unnecessary thermal polymerization of the radical polymerizable compound during preparation or storage of the coating solution. It is preferable to add a thermal polymerization inhibitor that can be used in products as a small amount of a thermal polymerization inhibitor.
The content of the thermal polymerization inhibitor is preferably about 0.01 to about 5% by mass with respect to the total solid content of the heat-sensitive layer.
[0195]
In addition, if necessary, higher fatty acid derivatives such as behenic acid and behenic acid amide may be added to prevent polymerization inhibition by oxygen and unevenly distributed on the surface of the heat-sensitive layer in the process of drying after coating. Good. The content of the higher fatty acid derivative is preferably about 0.1 to about 10% by mass with respect to the total solid content of the heat-sensitive layer.
[0196]
Furthermore, in a heat sensitive layer, various additives can be used together as needed. Specifically, the compound used as a component arbitrarily added to the thermal positive type thermosensitive layer mentioned above is mentioned.
[0197]
In order to obtain the lithographic printing plate precursor according to the invention by providing the heat sensitive layer, the same method as that for the thermal positive type heat sensitive layer may be used.
[0198]
The coating amount (solid content) of the heat-sensitive layer obtained by applying and drying is usually 0.5 to 5.0 g / m, although it varies depending on the application.²Is preferred. Various performances become suitable as it is the said range.
[0199]
<Non-treatment type>
As an untreated type heat-sensitive layer, for example, a polymer in which an irradiated portion generates a specific acidic group (for example, a phospho group, a sulfo group, or a carboxy group) and is solubilized by heating or irradiation with radiation, or irradiation. Examples thereof include a heat-sensitive layer containing a hydrophilic polymer matrix containing a compound (hereinafter, also referred to as “hydrophobizing precursor”) that can form a hydrophobic region.
[0200]
The polymer that generates and solubilizes a specific acidic group is preferably a sulfonic acid-generating polymer. For example, a sulfonic acid ester group, a disulfone group, or sec- or tert described in JP-A-10-282672. -The polymer etc. which have a sulfonamide group in a side chain can be mentioned.
[0201]
Examples of hydrophobizing precursors include:
(A) Hydrophobic fine particle polymer
(B) Microcapsules enclosing a hydrophobic substance
Is mentioned. These are fused to each other by heating, or the hydrophobized precursors encapsulated in the microcapsule cause a chemical reaction by heat to form an image area, that is, a hydrophobic area (parent ink area). sell. Since these hydrophobized precursors are preferably dispersed in a hydrophilic binder, after image recording (exposure), a lithographic printing plate precursor is mounted on a printing machine cylinder, dampening water and / or Alternatively, by supplying ink, on-press development can be performed without performing special development processing.
[0202]
The average particle diameter of the microcapsules enclosing the hydrophobic fine particle polymer and the hydrophobic substance is preferably 0.01 to 20 μm, and more preferably 0.05 to 5.0 μm. Within the above range, high-definition image formation is possible, and the temporal stability of the fine particle polymer is good.
[0203]
Examples of the hydrophobic fine particle polymer include a thermoplastic fine particle polymer, a thermosetting fine particle polymer, and a fine particle polymer having a thermoreactive functional group.
As the thermoplastic fine particle polymer, Research Disclosure No. 1 is used. 33303 (January 1992), JP-A-9-123387, JP-A-9-131850, JP-A-9-171249, JP-A-9-171250, and European Patent Application Publication No. 931,647. Suitable thermoplastic fine particle polymers can be mentioned.
Examples of the thermosetting fine particle polymer include a resin having a phenol skeleton, a urea resin (for example, urea or a derivatized urea derivative such as methoxymethylated urea with an aldehyde such as formaldehyde), a melamine resin (for example, Melamine or derivatives thereof formed by aldehydes such as formaldehyde), alkyd resins, unsaturated polyester resins, polyurethane resins, and epoxy resins.
[0204]
The microcapsules enclosing the hydrophobic substance include, for example, microcapsules enclosing the hydrophobic fine particle polymer, that is, thermoplastic fine particle polymer, thermosetting fine particle polymer, fine particle polymer having a thermoreactive functional group, and the like. An encapsulated microcapsule can be mentioned.
[0205]
However, particularly preferred as the hydrophobizing precursor is a microcapsule encapsulating a fine particle polymer having a thermoreactive functional group or a compound having a thermoreactive functional group.
Examples of the heat-reactive functional group commonly used for these include an ethylenically unsaturated group that undergoes a polymerization reaction (eg, acryloyl group, methacryloyl group, vinyl group, allyl group, vinyloxy group, etc.); an isocyanate group that undergoes an addition reaction, or The block, a functional group having an active hydrogen atom that is the reaction partner (for example, amino group, hydroxy group, carboxy group, etc.); an epoxy group that performs an addition reaction, an amino group, a carboxy group, or a hydroxy group that is the reaction partner Carboxy group and hydroxy group or amino group for performing condensation reaction; acid anhydride and amino group, hydroxy group or vinyloxy group for performing ring-opening addition reaction. However, any functional group capable of performing any reaction may be used as long as it has a function of forming a chemical bond by heating.
[0206]
Examples of the fine particle polymer having such a heat-reactive functional group include acryloyl group, methacryloyl group, vinyl group, allyl group, vinyloxy group, epoxy group, amino group, hydroxy group, carboxy group, isocyanate group, and acid anhydride; The thing which has the group which protected them can be mentioned. Introduction of these groups into the polymer particles may be performed at the time of polymerization, or may be performed after polymerization using a polymer reaction.
[0207]
When introduced at the time of polymerization, it is preferable to carry out emulsion polymerization or suspension polymerization of the monomer having these groups.
Specific examples of the monomer having such a group include compounds described in paragraph numbers [0018] to [0035] of JP-A No. 2001-293971, but the present invention is not limited thereto.
Examples of the monomer having no thermally reactive functional group that can be copolymerized with these monomers include styrene, alkyl acrylate, alkyl methacrylate, acrylonitrile, vinyl acetate and the like, and has a thermally reactive functional group. If it is a monomer which does not, it will not be limited to these.
Examples of the polymer reaction used when the introduction of the heat-reactive functional group is performed after polymerization include the polymer reaction described in International Publication No. 96/34316.
[0208]
The solidification temperature of the fine particle polymer having a heat-reactive functional group is preferably 70 ° C. or higher, but more preferably 100 ° C. or higher in view of stability over time.
[0209]
The content of the hydrophobic fine particle polymer is preferably 50% by mass or more, and more preferably 60% by mass or more based on the total solid content of the heat-sensitive layer.
[0210]
The microcapsule used in the present invention includes a hydrophobic substance, preferably a compound having the above-mentioned thermoreactive functional group. As the compound having a thermally reactive functional group, at least one selected from a polymerizable unsaturated group, a hydroxy group, a carboxy group, a carboxylate group, an acid anhydride, an amino group, an epoxy group, an isocyanate group, and a block form thereof. The compound which has the functional group of can be mentioned.
[0211]
As the compound having a polymerizable unsaturated group, a compound having at least one, preferably two or more ethylenically unsaturated bonds, for example, acryloyl group, methacryloyl group, vinyl group, allyl group, etc. is preferable. Groups are widely known in the industrial field, and these can be used without particular limitation in the present invention. These chemical forms include monomers, prepolymers, i.e. dimers, trimers and oligomers or mixtures thereof or copolymers thereof. Specific examples include those described in paragraph numbers [0016] to [0032] of JP-A No. 2001-277742.
[0212]
Specific examples of the compound having a polymerizable unsaturated group include unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.), esters and amides thereof. These include esters of unsaturated carboxylic acids and aliphatic polyhydric alcohols and amides of unsaturated carboxylic acids and aliphatic polyvalent amines.
Further, an addition reaction product of an unsaturated carboxylic acid ester or unsaturated carboxylic acid amide having a nucleophilic substituent such as a hydroxy group, an amino group, a mercapto group and the like with a monofunctional or polyfunctional isocyanate or epoxide, and a monofunctional Or a dehydration condensation reaction product with a polyfunctional carboxylic acid is also preferred.
In addition, addition reaction product of unsaturated carboxylic acid ester or amide having an electrophilic substituent such as isocyanate group or epoxy group with monofunctional or polyfunctional alcohol, amine and thiol, halogen group, tosyloxy group, etc. Preferred examples also include a substitution reaction product of an unsaturated carboxylic acid ester or amide having a leaving substituent with a monofunctional or polyfunctional alcohol, amine and thiol.
Another preferred example is a compound in which the unsaturated carboxylic acid is replaced with unsaturated phosphonic acid or chloromethylstyrene.
[0213]
Specific examples of the monomer of a compound having a polymerizable unsaturated group, which is an ester of an unsaturated carboxylic acid and an aliphatic polyhydric alcohol, include the ethylenically unsaturated bond-containing compound used in the photopolymer type photosensitive layer. Each acrylic acid ester, each methacrylic acid ester, each itaconic acid ester, each crotonic acid ester, each isocrotonic acid ester, and each maleic acid ester exemplified in the above. Specific examples include the compounds described in paragraph numbers [0021] to [0030] of JP-A No. 2001-293971.
[0214]
Examples of other compounds having a polymerizable unsaturated group include the same as those exemplified above as the radical polymerizable compound used in the thermal negative type heat-sensitive layer.
[0215]
Examples of the compound having an epoxy group include glycerin polyglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene diglycidyl ether, trimethylolpropane polyglycidyl ether, sorbitol polyglycidyl ether, bisphenols or polyphenols or hydrogenated polyglycidyl. Preferred examples include ether.
[0216]
Compounds having an isocyanate group include tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, xylylene diisocyanate, naphthalene diisocyanate, cyclohexanephenylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, cyclohexyl diisocyanate; blocking them with alcohol or amine Preferred examples of the compound are as follows.
[0217]
Preferable examples of the compound having an amino group include ethylenediamine, diethylenetriamine, triethylenetetramine, hexamethylenediamine, propylenediamine, and polyethyleneimine.
Preferred examples of the compound having a hydroxy group include compounds having a terminal methylol group, polyhydric alcohols such as pentaerythritol, bisphenols and polyphenols, and the like.
[0218]
Preferred examples of the compound having a carboxy group include aromatic polyvalent carboxylic acids such as pyromellitic acid, trimellitic acid and phthalic acid, and aliphatic polyvalent carboxylic acids such as adipic acid.
Preferable examples of the compound having an acid anhydride include pyromellitic acid anhydride and benzophenone tetracarboxylic acid anhydride.
Preferred examples of the compound having a vinyloxy group include compounds described in JP-A-2002-29162.
[0219]
Preferred examples of the copolymer of the compound having an ethylenically unsaturated bond include a copolymer of allyl methacrylate. Specific examples include allyl methacrylate / methacrylic acid copolymer, allyl methacrylate / ethyl methacrylate copolymer, allyl methacrylate / butyl methacrylate copolymer, and the like.
[0220]
As a method for producing a microcapsule encapsulating a hydrophobic substance, a known method such as an interfacial polymerization method for forming a capsule membrane, an in-situ method, a complex coacervate method, or a phase separation method from an organic solvent system can be used. Specifically, for example, a method described in paragraph [0036] of JP-A-2001-293971 can be used.
[0221]
It is preferable that the microcapsule wall used for the microcapsule encapsulating the hydrophobic substance has a three-dimensional cross-linking and has a property of swelling with a solvent. From this viewpoint, the wall material of the microcapsule is preferably polyurea, polyurethane, polyester, polycarbonate, polyamide, or a mixture thereof, and among them, polyurea and / or polyurethane is more preferable. You may introduce | transduce the compound which has the said thermoreactive functional group into the said microcapsule wall.
[0222]
The microcapsules encapsulating such a hydrophobic substance may be ones in which the microcapsules are combined by heat or may not be combined. In short, among the microcapsule inclusions, the one that oozes out of the capsule surface or outside the microcapsule at the time of application, or the one that penetrates into the microcapsule wall may cause a chemical reaction by heat. Moreover, you may react with the added hydrophilic resin or the added low molecular weight compound. In addition, two or more kinds of microcapsules may be reacted with each other by providing functional groups that thermally react with each other with different functional groups.
Therefore, it is preferable for image formation that the microcapsules are fused and united with heat, but it is not essential.
[0223]
The content of the microcapsules enclosing the hydrophobic substance in the heat-sensitive layer is preferably 10 to 60% by mass and more preferably 15 to 40% by mass with respect to the total solid content of the heat-sensitive layer. Within the above range, good on-press developability as well as good sensitivity and printing durability can be obtained.
[0224]
When microcapsules encapsulating a hydrophobic substance are contained in the heat-sensitive layer, a solvent that can dissolve the encapsulated substance and swell the wall material can be added to the microcapsule dispersion medium. By such a solvent, diffusion of the encapsulated compound having a thermally reactive functional group or the like outside the microcapsule is promoted. The selection of such a solvent depends on the microcapsule dispersion medium, the material of the microcapsule wall, the wall thickness, and the inclusions, but can be easily selected from many commercially available solvents. For example, in the case of a water-dispersible microcapsule comprising a crosslinked polyurea or polyurethane wall, alcohols, ethers, acetals, esters, ketones, polyhydric alcohols, amides, amines, fatty acids and the like are preferable.
[0225]
Specific examples include the same solvents as those exemplified above for the conventional positive type, but the present invention is not limited thereto. Two or more of these solvents may be used.
[0226]
A solvent that does not dissolve in the microcapsule dispersion but dissolves when the solvent is mixed can also be used. The amount added depends on the combination of materials. When the amount is less than the appropriate value, image formation is insufficient, and when the amount is large, the stability of the dispersion deteriorates. Usually, it is effective that it is 5-95 mass% of a coating liquid, it is preferable that it is 10-90 mass%, and it is more preferable that it is 15-85 mass%.
[0227]
If the untreated type heat-sensitive layer contains microcapsules containing a fine particle polymer having a heat-reactive functional group and / or a compound having a heat-reactive functional group, these reactions are initiated as necessary. A compound to be promoted or promoted may be added. Examples of the compound that initiates or accelerates the reaction include compounds that generate radicals or cations by heat. Examples thereof include lophine dimer, trihalomethyl compound, peroxide, azo compound, onium salt (diazonium salt, sulfonium salt, iodonium salt, etc.), acylphosphine, imide sulfonate and the like. Specifically, the compound illustrated as a radical generator used for a thermal negative type and the compound illustrated as a photo-acid generator used for a conventional positive type are mentioned, for example.
The content of these compounds is preferably 1 to 20% by mass and more preferably 3 to 10% by mass with respect to the total solid content of the heat-sensitive layer. If it is within the above range, good onset reaction reaction effect or reaction promoting effect can be obtained without impairing on-press developability.
[0228]
As the hydrophobizing precursor, it is particularly preferable to use self-water-dispersed fine particles having a hydrophilic periphery and capable of being dispersed in water. Since the self-water-dispersible fine particles have self-water dispersibility, they are easily and uniformly dispersed in the heat-sensitive layer coating used for forming the heat-sensitive layer. Even in the heat-sensitive layer (dry film) after drying, the particles are uniformly dispersed in the hydrophilic binder matrix without aggregation. Therefore, high-definition printing is possible and the dry film is stable over time.
[0229]
As self-water-dispersible fine particles, (1) a raw material resin having a lipophilic resin structural portion and a structural portion having a hydrophilic group in the molecule is disclosed in JP-A-3-221137 and JP-A-5-66600. Resin fine particles obtained by dispersing in water without an emulsifier or protective colloid by a phase inversion emulsification method as described in publications, etc., (2) having a core / shell structure, the core part being a lipophilic resin, the shell part Suitable examples include fine particles composed of a resin composed of a hydrophilic component, and (3) microcapsule fine particles obtained by encapsulating a hydrophobic substance and protecting the surface with a hydrophilic wall material.
A method for making the periphery of these fine particles hydrophilic is not particularly limited, and examples thereof include the same methods as described in paragraph numbers [0052] to [0056] of JP-A No. 2001-315552. .
[0230]
When the fine particle polymer and / or microcapsule is dispersed in a matrix made of a hydrophilic resin, the on-press development property is improved when the on-press development is performed, and the film strength of the thermosensitive layer itself is also improved. In addition, a lithographic printing plate precursor that does not require development processing can be obtained by crosslinking and curing the hydrophilic resin.
Examples of the hydrophilic resin include a hydroxy group, a carboxy group, a hydroxyethyl group, a hydroxypropyl group, an amino group, an aminoethyl group, and an aminopropyl group described in paragraph No. [0043] of JP-A-2001-293971. Those having a hydrophilic group such as a carboxymethyl group, and hydrophilic sol-gel conversion binder resins described in paragraphs [0063] to [0077] of JP-A No. 2000-335131 are preferred.
[0231]
The content of the hydrophilic resin is preferably 5 to 40% by mass and more preferably 10 to 30% by mass with respect to the total solid content of the heat-sensitive layer. Within the above range, good on-press developability can be obtained even when on-press development, and good film strength can be obtained.
[0232]
The hydrophilic resin may be used after being cured by crosslinking. Examples of the crosslinking agent that crosslinks and cures the hydrophilic resin include compounds that are usually used as crosslinking agents. Specifically, compounds described in Shinzo Yamashita, Tosuke Kaneko, “Crosslinker Handbook” published by Taiseisha (1981), “Polymer Data Handbook, Basic Shrinkage”, Baifukan (1986), etc. Can be used. Specific examples include the compounds described in paragraph No. [0053] of JP-A-2002-36745.
In addition, a crosslinking catalyst such as ammonium chloride, a silane coupling agent, a titanate coupling agent, or the like can be used in combination.
[0233]
In the non-treatment type heat-sensitive layer, it is preferable to use a sol-gel conversion binder resin among the hydrophilic resins. Details will be described below.
As a sol-gel conversion binder resin suitably used for an untreated type heat-sensitive layer, a bonding group coming out of a polyvalent element forms a network structure through an oxygen atom, and the polyvalent element is not bonded. It has a hydroxy group, an alkoxy group, etc., and is a polymer having a resinous structure in which these are mixed, and is in a sol state when there are many hydroxy groups, alkoxy groups, etc. A polymer body in which the network-like resin structure becomes stronger as it progresses can be mentioned.
[0234]
In addition to the property that the degree of hydrophilicity of the resin structure changes, the sol-gel conversion binder resin modifies the surface of the solid fine particles by binding some of the hydroxy groups to the solid fine particles, thereby changing the hydrophilicity. It also has work.
Examples of the polyvalent element having a hydroxy group, an alkoxy group and the like that perform sol-gel conversion include aluminum, silicon, titanium, and zirconium. Among these, a sol-gel conversion system using a siloxane bond using silicon is preferable. Hereinafter, a sol-gel conversion system using a siloxane bond will be described. A sol-gel conversion system using aluminum, titanium, zirconium, or the like can be implemented by replacing silicon described below with each element.
[0235]
A sol-gel conversion system based on a siloxane bond is a system including a silane compound having at least one silanol group capable of sol-gel conversion.
[0236]
The inorganic hydrophilic binder resin formed by sol-gel conversion is preferably a resin having a siloxane bond and a silanol group. An untreated type heat-sensitive layer is a sol system containing a silane compound having at least one silanol group, and is applied to a lithographic printing plate support. A structure of a siloxane skeleton is formed and gelation proceeds.
In addition, the heat-sensitive layer formed by this sol-gel conversion system contains an organic hydrophilic polymer, a cross-linking agent, and the like, which will be described later, for the purpose of improving physical performance such as film strength and flexibility, and improving coatability. You can also.
[0237]
Specific examples of the siloxane resin forming the gel structure and the silane compound having at least one silanol group include compounds described in paragraphs [0054] to [0057] of JP-A No. 2002-6504. Can be mentioned.
[0238]
For the formation of the inorganic hydrophilic binder resin, a metal compound capable of forming a film by bonding to the resin during sol-gel conversion such as Ti, Zn, Sn, Zr, Al, etc. is used together with the silane compound. it can.
As such a metal compound, for example, Ti (OR ′)_FourTiCl_FourZn (OR ')₂, Zn (CH_ThreeCOCHCOCH_Three)₂, Sn (OR ')_Four, Sn (CH_ThreeCOCHCOCH_Three)_Four, Sn (OCOR ')_Four, SnCl4, Zr (OR ')_Four, Zr (CH_ThreeCOCHCOCH_Three)_Four, Al (OR ')_Three, Al (CH_ThreeCOCHCOCH_Three)_ThreeEtc.
[0239]
Furthermore, in order to promote the hydrolysis reaction and polycondensation reaction of the above silane compound and the above metal compound that can be used in combination therewith, conventionally known acidic catalysts such as inorganic acid, carbonic acid, carboxylic acid, etc., ammonia, organic amine It is preferable to use a basic catalyst such as a catalyst together.
The catalyst can be used as it is or in a state in which the acid or basic compound is dissolved in a solvent such as water or alcohol (hereinafter referred to as an “acidic catalyst” using an acid, or using a basic compound). "Basic catalyst"). The concentration in the case of dissolving in a solvent is not particularly limited, but the higher the concentration, the faster the hydrolysis reaction and polycondensation reaction tend to be. However, when a basic catalyst having a high concentration is used, a precipitate may be generated in the sol solution. Therefore, the concentration of the basic catalyst (concentration in aqueous solution) is preferably 1 N or less.
[0240]
As described above, the non-treatment type heat-sensitive layer is preferably a heat-sensitive layer prepared by a sol-gel method (a heat-sensitive layer containing a sol-gel conversion binder resin as a hydrophilic resin). The details of the sol-gel method are as follows: Sakuo Sakuhana, "Science of Sol-Gel Method", Agne Jofusha (published) (1988), Satoshi Hirashima It is described in detail in books such as the General Technology Center (published) (1992).
[0241]
The content of the hydrophilic resin is preferably 5 to 70% by mass and more preferably 10 to 50% by mass with respect to the total solid content of the heat-sensitive layer. Within the above range, good on-press developability and film strength can be obtained.
[0242]
It is necessary to add an infrared absorber to the untreated type heat-sensitive layer. The infrared absorber may be a substance that absorbs light having a wavelength of 700 nm or more, and various pigments, dyes, and metal fine particles can be used.
[0243]
Examples of the pigment and the dye include those similar to those used in the above-described thermal positive type heat-sensitive layer.
Among these, as the pigment, carbon black whose surface is coated with a hydrophilic resin or silica sol is particularly preferable so that it can be easily dispersed with a water-soluble or hydrophilic resin and does not impair the hydrophilic property.
The particle diameter of the pigment is preferably in the range of 0.01 μm to 1 μm, and more preferably in the range of 0.01 μm to 0.5 μm.
As the dye, a water-soluble dye is particularly preferable. Specific examples include compounds described in paragraph numbers [0036] to [0041] of JP-A No. 2001-96936.
[0244]
The metal fine particles are not particularly limited as long as they are metal heat-convertible and heat-fused by light irradiation, but are described in paragraphs [0081] to [0082] of JP-A-2001-293971. In addition, it is preferably a fine particle of a simple substance or alloy of a metal belonging to Group 8 to 11 (Group VIII and IB), and it is a fine substance of a simple substance or alloy of a metal selected from Ag, Au, Cu, Pt and Pd. More preferably.
The metal fine particles are used by adding an aqueous solution of the above metal salt or complex salt to an aqueous solution containing a dispersion stabilizer, further adding a reducing agent to form a metal colloid, and then removing unnecessary salts. Specifically, for example, it is described in JP-A-2002-29165, JP-A-2000-335131, and the like.
[0245]
The average particle size of the metal colloid is preferably 1 to 500 nm, more preferably 1 to 100 nm, and still more preferably 1 to 50 nm. The degree of dispersion may be polydispersion, but monodispersion with a coefficient of variation of 30% or less is preferred.
[0246]
In the case of a pigment or a dye, the content of the infrared absorber is preferably 30% by mass or less, more preferably 5 to 25% by mass, and more preferably 7 to 20% by mass with respect to the total solid content of the heat-sensitive layer. % Is more preferable. In the case of metal fine particles, it is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably 20% by mass or more, based on the total solid content of the heat-sensitive layer. If the content of the metal fine particles is less than 5% by mass, the sensitivity may be lowered.
[0247]
In addition to the above-described components, the untreated type heat-sensitive layer can contain various compounds as required. For example, a polyfunctional monomer can be included in the matrix of the heat-sensitive layer in order to further improve the printing durability. As such a polyfunctional monomer, those exemplified as the monomer encapsulated in the microcapsule can be used. A particularly preferred monomer is trimethylolpropane triacrylate.
[0248]
In addition, a dye having a large absorption in the visible light region can be used as an image colorant in the non-process type heat-sensitive layer in order to make it easy to distinguish between an image area and a non-image area after image formation. . Specifically, the same compounds as the image colorant used in the above-described thermal positive type heat-sensitive layer are exemplified. In addition, pigments such as phthalocyanine pigments, azo pigments, and titanium oxide can also be suitably used.
These contents are preferably 0.01 to 10% by mass with respect to the total solid content of the heat-sensitive layer.
[0249]
Moreover, when a non-process type heat sensitive layer contains the compound which has an ethylenically unsaturated bond, in order to prevent the unnecessary thermal polymerization, it is preferable to add a small amount of thermal polymerization inhibitors.
Suitable thermal polymerization inhibitors include, for example, the compounds exemplified as the thermal polymerization inhibitor that can be used in the photopolymerizable composition of the above-described photopolymer type photosensitive layer.
The content of the thermal polymerization inhibitor is preferably about 0.01 to about 5% by mass with respect to the total solid content of the heat-sensitive layer.
[0250]
In addition, to the untreated type heat-sensitive layer, if necessary, a higher fatty acid derivative such as behenic acid or behenic acid amide is added to prevent polymerization inhibition by oxygen, and in the process of drying after coating. It may be unevenly distributed on the surface of the heat sensitive layer. The content of the higher fatty acid derivative is preferably about 0.1 to about 10% by mass with respect to the total solid content of the heat-sensitive layer.
[0251]
Furthermore, the non-treatment type heat-sensitive layer can contain a plasticizer in order to impart flexibility and the like of the coating film, if necessary. Examples of the plasticizer include the same compounds as those used in the above-described thermal positive type heat-sensitive layer.
[0252]
Further, the non-treatment type heat-sensitive layer can contain inorganic fine particles. Examples of the inorganic fine particles include silica, alumina, magnesium oxide, magnesium carbonate, calcium alginate and the like. Even if these are not photothermal convertible, they have effects such as strengthening of the film and strengthening of interfacial adhesion by surface roughening of the heat sensitive layer.
The content of the inorganic fine particles is preferably 1.0 to 70% by mass and more preferably 5.0 to 50% by mass with respect to the total solid content of the heat-sensitive layer. The effect expected to be 1% or less is small, and if it is 70% by mass or more, the originally required content of the infrared absorber may be restricted.
[0253]
Further, the non-treatment type heat-sensitive layer can contain hydrophilic sol-like particles. The average particle size of the hydrophilic sol-like particles is preferably 1 to 50 nm, and more preferably 1 to 40 nm. When the particle size of the hydrophilic sol-like particles is within the above range, the hydrophobized precursors such as metal fine particles contained as an infrared absorber in the hydrophilic resin and the above-described hydrophobic heat-meltable resin fine particles (It is hydrophobic in a state where it is not exposed to light and it becomes hydrophobic upon exposure) and can be stably dispersed to sufficiently maintain the film strength of the heat-sensitive layer. When printing as a lithographic printing plate, there is obtained an effect that the ink does not cause smearing of the ink on the non-image area and becomes extremely hydrophilic.
Suitable examples of the hydrophilic sol-like particles include silica sol, alumina sol, magnesium oxide sol, magnesium carbonate sol, and calcium alginate sol. Among these, silica sol, alumina sol, calcium alginate sol, or a mixture thereof is preferable.
Any of these hydrophilic sol-like particles can be easily obtained as a commercial product.
[0254]
The abundance ratio of the infrared absorber and the hydrophilic sol-like particles is preferably 100/0 to 30/70, more preferably 100/0 to 40/60, in terms of mass ratio.
The total content of the infrared absorber, the hydrophobized precursor, and the hydrophilic sol-like particles is preferably 2 to 95% by mass, and preferably 5 to 85% by mass with respect to the total solid content of the heat-sensitive layer. It is more preferable that
[0255]
The heat-sensitive layer is usually produced by applying a heat-sensitive layer coating solution obtained by dissolving the above components in a solvent onto a hydrophilic layer (an anodized film layer or an anodized film layer after hydrophilization). it can.
Examples of the solvent used here include the same solvents as those used in the above-described photopolymer type photosensitive layer, but the present invention is not limited thereto. These solvents are used alone or in combination.
The concentration of the above components (total solid content) in the solvent is preferably 1 to 50% by mass.
[0256]
As a coating method, various methods as described above can be used.
[0257]
In addition, the coating amount (solid content) of the heat-sensitive layer varies depending on the use, but is generally 0.5 to 5.0 g / m.²Is preferred. When the coating amount is less than the above range, the apparent sensitivity increases, but the film characteristics of the heat-sensitive layer that performs the function of image recording deteriorate.
[0258]
In the heat-sensitive layer in the present invention, a surfactant for improving the coating property, for example, a fluorine-based surfactant described in JP-A No. 62-170950 can be added. The addition amount of the surfactant is preferably 0.01 to 1% by mass and more preferably 0.05 to 0.5% by mass with respect to the total solid content of the heat-sensitive layer.
[0259]
<Overcoat layer>
An overcoat layer can be provided on the thermal sensitive layer of the thermal positive type, the thermal negative type, and the non-treatment type (hereinafter collectively referred to as “thermal type”).
The overcoat layer used in the present invention is a water-soluble layer and can be easily removed during development or printing. The overcoat layer has releasability in order to prevent sticking when the planographic printing plate precursors are stacked and stored.
[0260]
The main component of the overcoat layer is a water-soluble organic or inorganic polymer compound, and a film formed by applying and drying an aqueous solution thereof has film-forming ability.
Specific examples include water-soluble resins described in paragraph [0011] of JP-A No. 2001-162961, and celluloses described in JP-A No. 2002-19315.
[0261]
Moreover, the overcoat layer may contain other additives as required. For example, in order to increase releasability, it is preferable to contain a compound containing a water-soluble or water-dispersible fluorine atom and / or silicon atom.
Moreover, it is preferable to contain a photothermal conversion substance. As a photothermal conversion substance, the compound described in Unexamined-Japanese-Patent No. 2001-162961 is mentioned suitably, for example.
[0262]
The overcoat layer preferably has a surface dynamic friction coefficient (μk) of 2.5 or less, and more preferably 0.03 to 2.0. When the surface dynamic friction coefficient is within the above range, the transportability of the lithographic printing plate precursor is good, and the alkali developability or on-press developability and printing durability are also good.
Here, the “dynamic friction coefficient” of the surface is measured by a measuring method according to standard ASTM D1894. That is, the lithographic printing plate precursor is placed so that the surface of the underlying material is in contact with the back surface of the underlying material. The “back surface” means the surface on which the image recording layer and the overcoat layer are not provided on the lithographic printing plate support, and the “front surface” means the image recording layer on the lithographic printing plate support. And a surface on which an overcoat layer is provided. The dynamic friction coefficient can be obtained by stacking 3000 planographic printing plate precursors and leaving them to stand at 35 ° C. and 75% for 3 days, and then measuring the bottom sample.
[0263]
The overcoat layer of such a preferred embodiment is obtained by appropriately combining the type of water-soluble resin, surfactant, etc., the type of fluorine atom and / or compound containing silicon atom that increases releasability, and the amount of addition. Obtainable. For example, the ratio of the compound containing fluorine atoms and / or silicon atoms to the total solids of the overcoat layer is preferably 0.05 to 5.0% by mass, and preferably 0.1 to 3% by mass. Is more preferable.
[0264]
<Back coat layer>
In this way, on the back surface of the lithographic printing plate precursor of the present invention obtained by providing various image recording layers on the lithographic printing plate support of the present invention, an image in the case of being overlaid as necessary. In order to prevent the recording layer from being damaged, a coating layer made of an organic polymer compound (hereinafter referred to as “backcoat layer”) can be provided.
As the main component of the backcoat layer, at least one resin selected from the group consisting of a saturated copolymerized polyester resin, a phenoxy resin, a polyvinyl acetal resin, and a vinylidene chloride copolymer resin having a glass transition point of 20 ° C. or higher is preferably used. It is done.
The saturated copolyester resin is composed of a dicarboxylic acid unit and a diol unit. Dicarboxylic acid units include aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, tetrabromophthalic acid, tetrachlorophthalic acid; adipic acid, azelaic acid, succinic acid, oxalic acid, suberic acid, sebacic acid, malon Examples thereof include acids and saturated aliphatic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid.
[0265]
The backcoat layer further comprises dyes, pigments, etc. for coloring; silane coupling agents for improving adhesion to a lithographic printing plate support, diazo resins comprising diazonium salts, organic phosphonic acids, organic phosphoric acids , Cationic polymer, etc .; wax, higher fatty acid, higher fatty acid amide, silicone compound comprising dimethylsiloxane, modified dimethylsiloxane, polyethylene powder and the like, which are usually used as slipping agents, can be appropriately contained.
[0266]
The thickness of the backcoat layer may be basically such that the image recording layer is hardly damaged even if no interleaf is present, and is preferably 0.01 to 8 μm. When the thickness is 0.01 μm or less, it becomes difficult to prevent the image recording layer from being scratched when the planographic printing plate precursors are handled in layers. If the thickness exceeds 8 μm, the backcoat layer may swell and fluctuate due to chemicals used in the periphery of the lithographic printing plate during printing, and the printing pressure may change to deteriorate printing characteristics.
[0267]
Various methods can be applied to coat the back coat layer on the back surface of the lithographic printing plate precursor. For example, a method of applying and drying each of the above components in a suitable solvent solution or emulsified dispersion, a method of pasting a film-shaped product in advance with an adhesive or heat, a melt film using a melt extruder The method of forming and sticking is mentioned.
Among them, the method of applying the solution and drying it is preferable in securing the above-described application amount. As the solvent, an organic solvent described in JP-A-62-251739 is used alone or in combination. As the application method and conditions, many of the methods and conditions for applying the image recording layer can be used. That is, for example, a method using a coating rod, a method using an extrusion coater, and a method using a slide bead coater can be used.
The back coat layer may be provided before or after the image recording layer is provided, or may be provided simultaneously with the image recording layer.
[0268]
[Image formation and development processing]
The lithographic printing plate precursor according to the invention can be formed into a lithographic printing plate by performing conventionally known image formation (for example, exposure) and development treatment according to the type of the image recording layer.
Examples of the actinic ray light source used for image exposure include a carbon arc lamp, a mercury lamp, a metal halide lamp, a xenon lamp, a tungsten lamp, and a chemical lamp. Examples of the radiation include electron beam, X-ray, ion beam, far infrared ray, g-line, i-line, deep-UV light, and high-density energy beam (laser beam). Examples of the laser beam include a helium-neon laser (He-Ne laser), an argon laser, a krypton laser, a helium-cadmium laser, a KrF excimer laser, a semiconductor laser, a YAG laser, and a YAG-SHG laser.
In the case of a thermal type thermosensitive layer, a conventionally known thermal head system can also be used.
[0269]
Among these, photopolymer type and thermal type plate precursors exposed to laser light based on digital data and exposed to a desired image are preferably developed by a method using an alkali developer as described later.
When exposure and development are performed in this way, in the case of a positive lithographic printing plate precursor (thermal positive type), the laser beam is efficiently absorbed by the infrared absorber contained in the image recording layer in the exposed area. Only the image recording layer in the exposed area generates heat and becomes alkali-soluble due to the accumulation of absorbed energy due to exposure, and only the image recording layer in the exposed area is removed by the development process using an alkali developer to form a desired image. Is done. In the case of a negative type lithographic printing plate precursor (thermal negative type), the laser beam is efficiently absorbed by the infrared absorber contained in the image recording layer of the exposed portion, and the image of the exposed portion is accumulated by the accumulation of absorbed energy by exposure. Only the recording layer generates heat to generate an acid, and the cross-linking agent coexisting with the acid causes a cross-linking reaction, and only the image recording layer in the exposed area becomes alkali-insoluble, while the image recording layer in the unexposed area becomes an alkali developer. A desired image is formed by removing the film by development processing using the.
Similarly, when the image recording layer is a conventional positive type, an alkali developer described later can be preferably used. When the image recording layer is a conventional negative type, for example, a developer as described in JP-A-3-103857 can be used.
[0270]
Hereinafter, an alkaline developer (hereinafter also simply referred to as “developer”) used in the development processing of the above method will be described.
The alkaline developer used in the development treatment is an alkaline aqueous solution, and can be appropriately selected from conventionally known alkaline aqueous solutions. An alkaline aqueous solution containing an alkali silicate or non-reducing sugar and a base is preferable. Particularly preferred are those having a pH of 12.5 to 14.0.
[0271]
The alkali silicate exhibits alkalinity when dissolved in water, and examples thereof include alkali metal silicates such as sodium silicate, potassium silicate and lithium silicate; ammonium silicate and the like. These may be used alone or in combination of two or more.
[0272]
In alkaline aqueous solution using alkali silicate, silicon oxide SiO which is a component of silicate₂And alkali oxide M₂By adjusting the mixing ratio and concentration with O (M represents an alkali metal or ammonium group), the developability can be easily adjusted.
Among them, silicon oxide SiO₂And alkali oxide M₂Mixing ratio with O (SiO₂/ M₂O: molar ratio) of 0.5 to 3.0 is preferable, and 1.0 to 2.0 is more preferable. SiO₂/ M₂If O is less than 0.5, the alkali strength becomes stronger, so that an adverse effect of etching the aluminum plate used in the lithographic printing plate precursor may occur, and if it exceeds 3.0, Developability may be reduced.
[0273]
Moreover, it is preferable that the density | concentration of the alkali silicate in the said aqueous alkali solution is 1-10 mass%, It is more preferable that it is 3-8 mass%, It is still more preferable that it is 4-7 mass%. If the concentration is less than 1% by mass, the developability and processing ability may be reduced. If the concentration exceeds 10% by mass, precipitates and crystals are likely to be formed, and the gel is further neutralized at the time of waste liquid. This may cause trouble in waste liquid treatment.
[0274]
In an alkaline aqueous solution containing a non-reducing sugar and a base, the term “non-reducing sugar” means a sugar that does not have a reducing property because it has no free aldehyde group or ketone group. Non-reducing sugars are classified into trehalose-type oligosaccharides in which reducing groups are bonded, glycosides in which reducing groups of saccharides and non-saccharides are bonded, and sugar alcohols reduced by hydrogenation of saccharides. Can also be suitably used. Specific examples thereof include compounds described in JP-A-8-305039 and JP-A-11-216962.
[0275]
These non-reducing sugars may be used alone or in combination of two or more.
The content of the non-reducing sugar in the alkaline aqueous solution is preferably 0.1 to 30% by mass, and more preferably 1 to 20% by mass.
[0276]
As the base used in combination with the alkali silicate or the non-reducing sugar, a conventionally known alkali agent can be appropriately selected.
Examples of the alkaline agent include compounds described in paragraph numbers [0083] to [0084] of JP-A No. 11-216962. These may be used alone or in combination of two or more.
[0277]
Of these, sodium hydroxide and potassium hydroxide are preferable. This is because when these are used, the pH can be adjusted in a wide pH range by adjusting the amount added to the non-reducing sugar.
Further, trisodium phosphate, tripotassium phosphate, sodium carbonate, potassium carbonate and the like are preferable because they themselves have a buffering action.
[0278]
The alkali developer is obtained by adding a surfactant to the alkali aqueous solution described above. Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and fluorosurfactants. Surfactant may be used independently and may be used in combination of 2 or more type.
[0279]
The nonionic surfactant used for this invention is not specifically limited, A conventionally well-known thing can be used. For example, 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, polyglycerin fatty acid partial esters, Polyoxyethylenated castor oil, polyoxyethylene glycerin fatty acid partial esters, fatty acid diethanolamides, N N- bis-2-hydroxyalkylamines, polyoxyethylene alkylamines, triethanolamine fatty acid esters, trialkylamine oxides and the like.
Preferable examples include the compounds described in paragraph numbers [0062] to [0067] of JP-A No. 11-338126.
[0280]
Specific examples of the other surfactants include compounds described in paragraph numbers [0095] to [0099] of JP-A No. 11-338126.
[0281]
The surfactant content in the developer is preferably 0.1 to 15% by mass, more preferably 0.5 to 8.0% by mass, and 1.0 to 5.0% by mass. More preferably. When the content is too small, the developability and the solubility of the photosensitive layer components are lowered. On the other hand, when the content is too large, the printing durability of the lithographic printing plate is lowered.
[0282]
The alkaline developer can contain a chelating agent. Examples of chelating agents include Na₂P₂O₇, Na_FiveP_ThreeO_Three, Na_ThreeP_ThreeO₉, Na₂O_FourP (NaO_ThreeP) PO_ThreeNa₂Polyphosphates such as Calgon (sodium polymetaphosphate); ethylenediaminetetraacetic acid, its potassium salt, its sodium salt, diethylenetriaminepentaacetic acid, its potassium salt, sodium salt, triethylenetetraminehexaacetic acid, its potassium salt, its sodium salt, Hydroxyethylethylenediaminetriacetic acid, its potassium salt, its sodium salt, nitrilotriacetic acid, its potassium salt, its sodium salt, 1,2-diaminocyclohexanetetraacetic acid, its potassium salt, its sodium salt, 1,3-diamino-2- Aminopolycarboxylic acids such as propanoltetraacetic acid, potassium salt, sodium salt thereof; 2-phosphonobutanetricarboxylic acid-1,2,4, potassium salt, sodium salt, 2-phosphonobutanone tricarl Acid-2,3,4, potassium salt, sodium salt, 1-phosphonoethanetricarboxylic acid-1,2,2, potassium salt, sodium salt, 1-hydroxyethane-1,1-diphosphonic acid Organic phosphonic acids such as potassium salt, sodium salt, aminotri (methylenephosphonic acid), potassium salt, sodium salt, and the like.
[0283]
The content of the chelating agent is determined according to the hardness of the hard water used and the amount used, but is preferably 0.001 to 5% by mass in the developer at the time of use, and 0.01 to 1 It is more preferably 0.0% by mass, and even more preferably 0.05 to 0.5% by mass.
[0284]
The following additives can be added to the alkaline developer used in the present invention for the purpose of further improving development performance.
For example, neutral salts such as NaCl, KCl and KBr described in JP-A-58-75152, chelating agents such as EDTA and NTA described in JP-A-58-190952, No. 59-121336 [Co (NH_Three)₆] Cl_ThreeCoCl₂・ 6H₂Complexes such as O, anionic or amphoteric surfactants such as sodium alkylnaphthalene sulfonate and n-tetradecyl-N, N-dihydroxyethylbetaine described in JP-A-50-51324, US Pat. No. 4,374 , 920, nonionic surfactants such as tetramethyl decyne diol, p-dimethylaminomethyl polystyrene methyl chloride quaternary compounds described in JP-A-55-95946, etc. Cationic polymers, amphoteric polymer electrolytes such as copolymers of vinylbenzyltrimethylammonium chloride and sodium acrylate described in JP-A-56-142528, and JP-A-57-192951 Reducing inorganic salts such as sodium sulfite, Japanese Patent Application Laid-Open No. 58-59444 Inorganic lithium compounds such as lithium chloride described, Organometallic surfactants containing organic Si, organic Ti, etc. described in JP-A-59-75255, described in JP-A-59-84241 Organic boron compounds that have been used.
[0285]
In addition, for the purpose of increasing the development residue dispersibility and the ink affinity of the image portion of the lithographic printing plate precursor, the alkaline developer may contain a development stabilizer, an organic solvent, a reducing agent, an organic solvent as necessary. Carboxylic acid, hard water softener, preservative, colorant, thickener, antifoaming agent and the like may be added.
Examples thereof include compounds described in paragraph numbers [0101] to [0110] of JP-A No. 11-216962, but the present invention is not limited thereto.
[0286]
The usage mode of the alkaline developer used in the present invention is not particularly limited.
In recent years, in particular, in the plate making / printing industry, automatic developing machines for printing plates have been widely used in order to rationalize and standardize plate making operations.
This automatic developing machine generally comprises a developing unit and a post-processing unit, and has an apparatus for conveying the printing plate, each processing liquid tank, and a spray device. Each processing solution pumped up is sprayed from a spray nozzle to perform development processing. In addition, recently, a method is also known in which a printing plate is immersed and conveyed by a submerged guide roll or the like in a processing liquid tank filled with the processing liquid. In such automatic processing, each processing solution can be processed while being supplemented with a replenisher according to the processing amount, operating time, and the like.
[0287]
In this case, a large amount of printing plate can be processed without replacing the developer in the developer tank for a long time by adding an aqueous solution having a higher alkali strength than the developer as a replenisher to the developer. When using the alkaline developer used in the present invention, it is preferable to employ this replenishment method.
As the replenisher, for example, the alkali developer described above having a higher alkali strength than the developer for development can be used.
[0288]
In the developer and replenisher, various surfactants other than the above, organic solvents, etc. may be added as necessary for the purpose of promoting or suppressing developability, improving the dispersion of development residue and improving the ink affinity of the image area. It can also be added. As the surfactant, an anionic surfactant, a nonionic surfactant or an amphoteric surfactant is preferable. As the organic solvent, benzyl alcohol and the like are preferable. Further, addition of polyethylene glycol or a derivative thereof, polypropylene glycol or a derivative thereof, or the like is also preferable.
Furthermore, if necessary, inorganic quinone reducing agents such as hydroquinone, resorcin, sodium sulfite or sodium sulfite, potassium sulfite, etc .; organic carboxylic acid, antifoaming agent, water softener, etc. can be added.
[0289]
The lithographic printing plate of the present invention obtained by development using the alkali developer and replenisher described above is generally a rinse solution containing washing water, a surfactant, etc., gum arabic, and a non-sensitive oil containing a starch derivative. A post-treatment is performed using the chemical solution. In this post-treatment, these treatment liquids can be combined in various ways.
Moreover, it can also be set as what is called a disposable processing system processed with a substantially unused alkali developing solution.
[0290]
Moreover, the processing method of the lithographic printing plate which develops using the developing solution which does not contain an alkali metal silicate substantially, after exposing to the lithographic printing plate precursor as shown below. When this method is used, there is a problem in developing with a developer containing an alkali metal silicate, namely SiO 2₂In the neutralization treatment when processing the waste liquid of the developer,₂Generation | occurrence | production of problems, such as the gel resulting from this, can be prevented. This method is described in detail in JP-A No. 11-109637, and in the present invention, the contents described in the publication can be used.
[0291]
(1) Exposure
In this method, image exposure is performed before development processing. As an actinic ray light source used for image exposure, those exemplified above can be used.
[0292]
(2) Development
After the exposure, it is preferable to perform development using a developer containing substantially no alkali metal silicate.
A preferred developer used in this method is not particularly limited as long as it is a developer that does not substantially contain an alkali metal silicate, but is preferably an alkaline aqueous solution that does not substantially contain an organic solvent. However, an organic solvent may be contained if necessary.
The developer preferably contains a saccharide. For example, a developer containing at least one compound selected from non-reducing sugars and at least one base as the main component and having a pH of 9.0 to 13.5 can be mentioned.
[0293]
In addition, when the image recording layer is an unprocessed type, after exposure to a plate-making original plate, the lithographic printing plate can be easily processed with water or an aqueous solution without developing with an alkali developer as described above. can do. In this case, it is preferable to use an aqueous solution containing substantially no alkali metal silicate.
For example, an alkaline aqueous solution that may contain an organic solvent may be used as necessary. This aqueous solution may further contain a compound selected from saccharides (for example, non-reducing saccharides).
Further, this unprocessed type lithographic printing plate precursor is subjected to exposure and image recording, and then attached to the plate cylinder of a printing machine without processing. For example, (1) fountain solution is applied to the lithographic printing plate precursor. Supplying and developing on-machine, then supplying ink to start printing, (2) supplying dampening water and ink to the lithographic printing plate precursor, developing on-machine, and then supplying ink Printing can be performed by a method of starting printing, and (3) a method of supplying ink to the planographic printing plate precursor, supplying dampening water, and simultaneously supplying paper to start printing.
[0294]
Further, as described in Japanese Patent No. 2938398, an unprocessed type lithographic printing plate precursor is recorded on an image by a laser or a thermal head mounted on a printing press after being mounted on a plate cylinder. Alternatively, the fountain solution and / or ink can be supplied for on-press development.
That is, the untreated type lithographic printing plate precursor can preferably be developed with water or an aqueous solution, and can be mounted on a printing machine and printed without being developed.
[0295]
【Example】
EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
<Example of thermal positive type planographic printing plate precursor>
1. Creating a lithographic printing plate precursor
(Example 1)
Si: 0.06 mass%, Fe: 0.30 mass%, Cu: 0.005 mass%, Mn: 0.001 mass%, Mg: 0.001 mass%, Zn: 0.001 mass%, Ti: It contains 0.03% by mass, and the balance is prepared using Al and an inevitable impurity aluminum alloy. After the molten metal treatment and filtration, an ingot having a thickness of 500 mm and a width of 1200 mm is obtained by a DC casting method. Created. After the surface was shaved with a chamfering machine with an average thickness of 10 mm, it was kept soaked at 550 ° C. for about 5 hours, and when the temperature dropped to 400 ° C., rolling with a thickness of 2.7 mm using a hot rolling mill A board was used. Further, after heat treatment was performed at 500 ° C. using a continuous annealing machine, an aluminum plate having a thickness of 0.24 mm was finished by cold rolling. After making this aluminum plate 1030 mm in width, the following surface treatment was continuously performed.
[0296]
(A) Mechanical roughening treatment
A roller-type nylon brush that rotates while supplying a suspension of abrasive (silica sand) having a specific gravity of 1.12 and water as a polishing slurry to the surface of the aluminum plate using the apparatus shown in FIG. The surface was mechanically roughened. The average particle size of the abrasive was 8 μm, and the maximum particle size was 50 μm. The material of the nylon brush was 6 · 10 nylon, the hair length was 50 mm, and the hair diameter was 0.3 mm. The nylon brush was planted so as to be dense by making a hole in a stainless steel tube having a diameter of 300 mm. Three rotating brushes were used. The distance between the two support rollers (φ200 mm) at the bottom of the brush was 300 mm. The brush roller was pressed until the load of the drive motor for rotating the brush became 7 kW plus with respect to the load before the brush roller was pressed against the aluminum plate. The rotating direction of the brush was the same as the moving direction of the aluminum plate. The rotation speed of the brush was 200 rpm.
[0297]
(B) Alkali etching treatment
The aluminum plate obtained above was subjected to an etching process by spraying at a caustic soda concentration of 2.6 mass%, an aluminum ion concentration of 6.5 mass%, and a temperature of 70 ° C.²Dissolved. Then, water washing by spraying was performed.
[0298]
(C) Desmut treatment
A desmut treatment was performed by spraying with a 1% by weight aqueous solution of nitric acid at a temperature of 30 ° C. (containing 0.5% by weight of aluminum ions), and then washed with water by spraying. The nitric acid aqueous solution used for the desmut was the waste liquid from the step of electrochemical surface roughening using alternating current in nitric acid aqueous solution.
[0299]
(D) Electrochemical roughening treatment
An electrochemical surface roughening treatment was continuously performed using an alternating voltage of 60 Hz. The electrolytic solution at this time was a 10.5 g / L nitric acid aqueous solution (containing 5 g / L aluminum ions and 0.007 mass% ammonium ions) at a temperature of 50 ° C. The AC power supply waveform is the waveform shown in FIG. 2, the time TP until the current value reaches the peak from zero is 0.8 msec, the duty ratio is 1: 1, the trapezoidal rectangular wave AC is used, with the carbon electrode as the counter electrode An electrochemical roughening treatment was performed. Ferrite was used for the auxiliary anode. The electrolytic cell used was the one shown in FIG.
The current density is 30 A / dm at the peak current value.²The amount of electricity is 220 C / dm in terms of the total amount of electricity when the aluminum plate is the anode.²Met. 5% of the current flowing from the power source was shunted to the auxiliary anode.
Then, water washing by spraying was performed.
[0300]
(E) Alkali etching treatment
The aluminum plate was etched at 32 ° C. with a caustic soda concentration of 26 mass% and an aluminum ion concentration of 6.5 mass%, and the aluminum plate was 0.20 g / m.²Dissolve and remove the smut component mainly composed of aluminum hydroxide that was generated when electrochemical roughening was performed using alternating current in the previous stage, and dissolve the edge part of the generated pit to produce the edge part Made smooth. Then, water washing by spraying was performed.
[0301]
(F) Desmut treatment
A desmutting treatment was performed by spraying with a 25% by weight aqueous solution of sulfuric acid having a temperature of 60 ° C. (containing 0.5% by weight of aluminum ions), and then washing with water by spraying.
[0302]
(G) Anodizing treatment
The anodizing apparatus of the two-stage feed electrolytic treatment method having the structure shown in FIG. 4 (first and second electrolysis unit length 6 m each, first and second feed unit length 3 m each, first and second feed electrode length 2.4 m each) Anodizing was performed using this. Sulfuric acid was used as the electrolytic solution supplied to the first and second electrolysis units. All electrolytes had a sulfuric acid concentration of 50 g / L (containing 0.5 mass% of aluminum ions) and a temperature of 20 ° C. Then, water washing by spraying was performed.
[0303]
In the anodizing device, currents from the power sources 67a and 67b flow to the first power supply electrode 65a provided in the first power supply portion 62a, flow to the aluminum plate 11 through the electrolytic solution, and in the first electrolysis portion 63a. An oxide film is generated on the surface of the aluminum plate 11, passes through the electrolytic electrodes 66a and 66b provided in the first electrolysis part 63a, and returns to the power sources 67a and 67b.
On the other hand, the currents from the power supplies 67c and 67d flow to the second power supply electrode 65b provided in the second power supply portion 62b, flow to the aluminum plate 11 through the electrolytic solution in the same manner as described above, and in the second electrolysis portion 63b, aluminum flows. An oxide film is formed on the surface of the plate 11.
[0304]
The amount of electricity fed from the power sources 67a and 67b to the first feeding unit 62a is equal to the amount of electricity fed from the power sources 67c and 67d to the second feeding unit 62b, and the first electrolysis unit 63a and the second electrolysis unit Both current densities at 63b are about 30 A / dm²Met. In the 2nd electric power feeding part 62b, 1.35 g / m produced | generated by the 1st electrolysis part 63a.²Power is supplied through the oxide film surface. The final oxide film amount is 2.7 g / m²Met.
[0305]
(H) Alkali metal silicate treatment
An aluminum support obtained by anodizing (the support for a lithographic printing plate of the present invention) is immersed in a treatment layer of a 1% by weight aqueous solution of sodium silicate No. 3 at a temperature of 30 ° C. for 10 seconds to obtain an alkali. Metal silicate treatment (silicate treatment) was performed. Thereafter, water was washed by spraying using well water.
[0306]
(I) Formation of intermediate layer (undercoat layer)
On the aluminum support after the alkali metal silicate treatment obtained as described above (support for lithographic printing plate of the present invention), an undercoat solution having the following composition was applied and dried at 80 ° C. for 15 seconds. A coating film was formed. The coating amount after drying is 15 mg / m²Met.
[0307]
<Undercoat liquid composition>
-Polymer compound represented by the following formula 0.3 g
・ Methanol 100g
・ Water 1g
[0308]
[Chemical 1]

[0309]
(J) Formation of heat-sensitive layer
Next, a heat-sensitive layer coating solution 1 having the following composition was prepared, and the coating amount (heat-sensitive layer coating amount) after drying the heat-sensitive layer coating solution 1 on an undercoated aluminum support was 1.0 g / m.²And dried to form a heat-sensitive layer (thermal positive type image recording layer) to obtain a planographic printing plate precursor of Example 1.
[0310]
<Thermosensitive layer coating solution 1 composition>
・ Capric acid 0.03g
-Specific copolymer 1 described later 0.75 g
-M, p-cresol novolak (m / p ratio = 6/4, weight average molecular weight 3,500, containing 0.5% by mass of unreacted cresol) 0.25 g
・ 0.003 g of p-toluenesulfonic acid
・ Tetrahydrophthalic anhydride 0.03 g
-Cyanine dye A represented by the following formula 0.017 g
[0311]
[Chemical formula 2]

[0312]
0.015 g of a dye having 1-naphthalenesulfonic acid anion as a counter ion of Victoria Pure Blue BOH
・ Fluorine-based surfactant (Megafac F-177, manufactured by Dainippon Ink & Chemicals, Inc.) 0.05 g
・ Γ-Butyllactone 10g
・ Methyl ethyl ketone 10g
1-methoxy-2-propanol 1g
[0313]
<Specific copolymer 1>
In a 500 mL three-necked flask equipped with a stirrer, a condenser, and a dropping funnel, 31.0 g (0.36 mol) of methacrylic acid and 39. 1 g (0.36 mol) and 200 mL of acetonitrile were added, and the mixture was stirred while cooling with an ice-water bath. To this mixture, 36.4 g (0.36 mol) of triethylamine was dropped with a dropping funnel over about 1 hour. After completion of the dropwise addition, the ice water bath was removed, and the mixture was stirred at room temperature for 30 minutes.
[0314]
To this reaction mixture, 51.7 g (0.30 mol) of p-aminobenzenesulfonamide was added, and the mixture was stirred for 1 hour while warming to 70 ° C. in an oil bath. After completion of the reaction, the mixture was added to 1 L of water while stirring the water, and the resulting mixture was stirred for 30 minutes. The mixture was filtered to take out a precipitate, which was slurried with 500 mL of water, and then the slurry was filtered, and the obtained solid was dried to dry a white solid of N- (p-aminosulfonylphenyl) methacrylamide. Was obtained (yield 46.9 g).
[0315]
Next, 4.61 g (0.0192 mol) of N- (p-aminosulfonylphenyl) methacrylamide and 2.94 g of ethyl methacrylate were added to a 20 mL three-necked flask equipped with a stirrer, a condenser and a dropping funnel. 0.0258 mol), 0.80 g (0.015 mol) of acrylonitrile and 20 g of N, N-dimethylacetamide were added, and the mixture was stirred while heating to 65 ° C. with a hot water bath. To this mixture, 0.15 g of “V-65” (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the mixture was stirred for 2 hours under a nitrogen stream while being kept at 65 ° C. A further mixture of 4.61 g of N- (p-aminosulfonylphenyl) methacrylamide, 2.94 g of ethyl methacrylate, 0.80 g of acrylonitrile, N, N-dimethylacetamide and 0.15 g of “V-65” was added to this reaction mixture. It dropped by the dropping funnel over 2 hours. After completion of the dropwise addition, the obtained mixture was further stirred at 65 ° C. for 2 hours. After completion of the reaction, 40 g of methanol was added to the mixture, cooled, and the resulting mixture was added to 2 L of water while stirring the water. After stirring the mixture for 30 minutes, the precipitate was removed by filtration and dried. 15 g of the specific copolymer 1 as a white solid was obtained.
It was 53,000 (polystyrene standard) when the weight average molecular weight of the obtained specific copolymer 1 was measured by the gel permeation chromatography.
[0316]
(Example 2)
In the above (g) anodic oxidation treatment, a 4% by mass ammonium borate aqueous solution is used as the electrolytic solution, and the current density in both the first electrolytic unit 63a and the second electrolytic unit 63b is 0.1 A / dm.²A lithographic printing plate precursor of Example 2 was obtained in the same manner as in Example 1 except that low current electrolysis was used.
[0317]
(Example 3)
In the above (d) electrochemical surface roughening treatment, the electrolyte is an aqueous solution of 7.5 g / L hydrochloric acid (containing 5 g / L of aluminum ions), and the current density is 25 A / dm at the peak current value.²The amount of electricity is 50 C / dm in terms of the total amount of electricity when the aluminum plate is the anode.²A lithographic printing plate precursor of Example 3 was obtained in the same manner as in Example 1 except that.
[0318]
(Example 4)
A lithographic printing plate precursor of Example 4 was obtained in the same manner as in Example 1 except that the Cu content in the aluminum plate used was 0.017% by mass.
[0319]
(Example 5)
(G) After the anodizing treatment and before the (h) alkali metal silicate treatment, the same procedure as in Example 1 was followed, except that the sealing treatment was performed using pressurized steam as described below. 5 lithographic printing plate precursors were obtained.
The sealing treatment was performed by treatment for 10 seconds in a vapor chamber saturated at 100 ° C. and 1 atm.
[0320]
(Example 6)
In the above (d) electrochemical surface roughening treatment, a 10 g / L aqueous solution of nitric acid (containing 5 g / L of aluminum ions and 0.007% by mass of ammonium ions) is used as the electrolytic solution, and the temperature of the electrolytic solution is 80. ° C, TP is 0 msec, and the amount of electricity is 130 C / dm as the total amount of electricity when the aluminum plate is the anode²A lithographic printing plate precursor of Example 6 was obtained in the same manner as in Example 1 except that.
[0321]
(Comparative Example 1)
A lithographic printing plate precursor of Comparative Example 1 was obtained in the same manner as in Example 1 except that (a) the mechanical surface roughening treatment was not performed.
[0322]
(Comparative Example 2)
In the above (d) electrochemical surface roughening treatment, the frequency of the AC voltage used is 3 Hz, the temperature of the electrolyte is 35 ° C., and the amount of electricity is 400 C / dm in terms of the total amount of electricity when the aluminum plate is the anode.²A lithographic printing plate precursor of Comparative Example 2 was obtained in the same manner as in Example 1 except that.
[0323]
(Comparative Example 3)
(G) In the anodizing treatment, the same as in Example 1 except that the sulfuric acid concentration of the electrolytic solution was 250 g / L (containing 0.5 mass% of aluminum ions) and the temperature of the electrolytic solution was 50 ° C. By the method, a planographic printing plate precursor of Comparative Example 3 was obtained.
[0324]
(Comparative Example 4)
In the above (g) anodic oxidation treatment, a 50 g / L phosphoric acid aqueous solution is used as the electrolytic solution, and the current density in the first electrolytic unit 63a and the second electrolytic unit 63b is both 20 A / dm.²A lithographic printing plate precursor of Comparative Example 4 was obtained in the same manner as in Example 1 except that.
[0325]
(Comparative Example 5)
In the above (e) alkali etching treatment, the temperature of the aluminum plate is adjusted to 1.0 g / m by adjusting the liquid temperature.²A planographic printing plate precursor of Comparative Example 5 was obtained in the same manner as in Example 1 except that.
[0326]
2. Measurement of average diameter of pits (medium wave structure) on lithographic printing plate support and observation of minute irregularities (small wave structure) inside pits
The surface of the lithographic printing plate support was photographed with a scanning electron microscope (SEM) at a magnification of 10,000 times from the direction perpendicular to the support. In the SEM photograph, the diameter of 30 pits was measured, and the average diameter of the pits was obtained. Further, in the SEM photograph, it was observed whether or not there were fine irregularities inside the pit.
The results are shown in Table 1.
[0327]
3. Measurement of the wavelength of the large wave structure on the surface of a lithographic printing plate support
After the heat-sensitive layer of the lithographic printing plate precursor was dissolved and removed with γ-butyrolactone, the exposed surface was magnified 2000 times from the direction normal to 30 ° C. using a T-20 scanning electron microscope manufactured by JEOL Ltd. Observation was performed at a magnification of 2, and 30 wavelength components larger than 2 μm were measured in the horizontal direction to determine the average wavelength.
The results are shown in Table 1. In Table 1, “-” indicates that there was no concave portion of the corresponding wavelength.
[0328]
4). Measurement of average pore diameter and average pore density of micropores
The heat-sensitive layer of the lithographic printing plate precursor is dissolved and removed with γ-butyl lactone, and further ultrasonically washed in γ-butyl lactone for 30 minutes, and then the exposed surface is FE-SEM (S-900, manufactured by Hitachi, Ltd.) SEM photographs were taken at a magnification of 150,000 times without vapor deposition. Three fields of view were observed with an SEM photograph, the pore diameter was measured for 100 pores, and the average value was taken as the average pore diameter.
Further, from the SEM photograph, three fields of 300 nm square were extracted, the number of pores therein was counted, the average value of the pore density was obtained, and the average pore density was obtained.
The results are shown in Table 1.
[0329]
5). Evaluation of scratch resistance of lithographic printing plate precursors
The lithographic printing plate precursor obtained as described above was evaluated for scratch resistance.
A slip sheet was placed on the surface of the heat-sensitive layer of the lithographic printing plate precursor, and the upper and lower sides were sandwiched between corrugated cardboard sheets, which were left for 3 days in an environment of 25 ° C and 50% RH. After that, the surface of the lithographic printing plate precursor is rubbed 5 times with cotton gloves and developed with an automatic processor 900NP using a developer DT-1 for PS plate manufactured by Fuji Photo Film Co., Ltd. under standard operating conditions. did. The extent to which the rubbed portion was damaged and whitened was visually observed and evaluated.
The case where there was no change from before development was indicated by ◯, the case where the support was almost visible and the color of the heat-sensitive layer was hardly visible was indicated by ×, and the intermediate levels were indicated by ○ Δ, Δ, Δ ×.
The results are shown in Table 1.
[0330]
6). Evaluation of lithographic printing plate precursor sensitivity
The lithographic printing plate precursor is exposed entirely by changing the plate surface energy amount using a TrendSetter 3244 manufactured by CREO, and then automatically using a developer DT-1 for PS plate manufactured by Fuji Photo Film Co., Ltd. under standard operating conditions. It developed with the developing machine 900NP. Sensitivity was evaluated by the amount of plate surface energy when it was visually observed that the heat-sensitive layer was completely removed.
The results are shown in Table 1.
[0331]
7. Evaluation of stain resistance of lithographic printing plate precursors
A lithographic printing plate precursor has an output of 500 mW, a wavelength of 830 nm, a beam diameter of 17 μm (1 / e²) Using a TrendSetter 3244 manufactured by CREO equipped with a semiconductor laser, a main scanning speed of 5 m / sec, and a plate surface energy amount of 140 mJ / cm.²And imagewise exposure.
Thereafter, D-sorbite / potassium oxide K, which is a combination of a non-reducing sugar and a base₂To 1 L of an aqueous solution containing 5.0% by mass of a potassium salt composed of O and 0.015% by mass of Olphine AK-02 (manufactured by Nissin Chemical)₁₂H_{twenty five}N (CH₂CH₂COONa)₂Development processing was performed using an alkaline developer added with 1 g of. The development processing was performed using an automatic processor PS900NP (Fuji Photo Film Co., Ltd.) filled with the alkali developer under the conditions of a development temperature of 25 ° C. and 12 seconds. After completion of the development treatment, a lithographic printing plate in which plate making was completed was obtained through a water washing step and treatment with a gum (GU-7 (1: 1)).
The lithographic printing plate thus obtained was used to print on a Mitsubishi diamond type F2 printing machine (Mitsubishi Heavy Industries, Ltd.) using DIC-GEOS (s) red ink, and after printing 10,000 sheets Blanket dirt was visually evaluated.
[0332]
8). Evaluation of printing durability of lithographic printing plate precursor
Using a lithographic printing plate obtained by the same method as the evaluation of stain resistance, using a Lithrone printing machine manufactured by Komori Corporation, using DIC-GEOS (N) black ink manufactured by Dainippon Ink & Chemicals, Inc. Printing durability was evaluated based on the number of printed sheets when it was visually confirmed that the density of the solid image started to decrease.
[0333]
It can be seen that the lithographic printing plate precursor of the present invention using the lithographic printing plate support of the present invention is hardly scratched and has excellent sensitivity (Examples 1 to 6). In particular, when the Cu content in the used aluminum plate is 0.005% by mass (Examples 1 to 3, 5 and 6), the average diameter of the pits constituting the medium wave structure tends to be small and uniform. It is hard to be damaged.
On the other hand, Comparative Examples 1-5 are smoothed by reducing the unevenness on the surface of the heat-sensitive layer as in Examples 1-6, but have the following drawbacks. That is, when there is no large wave structure on the surface of the lithographic printing plate support (Comparative Example 1) and when the wavelength of the large wave structure is too long (Comparative Example 2), separation occurs between the heat-sensitive layer and the support. Easy to get scratched. Moreover, when the average pore density of the micropores of the anodized film is too high (Comparative Example 3) and when the average pore diameter is too large (Comparative Example 4), the sensitivity is poor. Furthermore, when there is no fine unevenness inside the pit (Comparative Example 5), peeling occurs between the heat-sensitive layer and the support and is easily damaged.
Moreover, the lithographic printing plate precursor of the present invention using the lithographic printing plate support of the present invention was superior in stain resistance and printing durability as compared with the lithographic printing plate precursors of Comparative Examples 1 to 5.
[0334]
[Table 1]

[0335]
<Example of thermal negative type lithographic printing plate precursor>
1. Creating a lithographic printing plate precursor
(Examples 7 to 12 and Comparative Example 6)
In the same manner as in Examples 1 to 6 and Comparative Example 5, except that (h), (i) and (j) were not performed, and (k), (l) and (m) were performed, A lithographic printing plate precursor was obtained.
[0336]
(K) Alkali metal silicate treatment
Alkali metal is obtained by immersing each aluminum support (support for lithographic printing plate of the present invention) obtained by anodizing treatment in a treatment layer of a 2 mass% aqueous solution of sodium silicate at a temperature of 25 ° C. for 15 seconds. Silicate treatment (silicate treatment) was performed. Then, water washing by spraying was performed.
[0337]
(L) Formation of intermediate layer (undercoat layer)
On the aluminum support (the lithographic printing plate support of the present invention) after the alkali metal silicate treatment obtained as described above, an undercoat liquid described later was applied, and the amount of Si on the support was 3 mg / mg. m²It was coated so that
[0338]
The undercoat liquid was prepared as follows.
First, the following compounds were mixed and stirred. An exotherm was observed in about 5 minutes. After reacting for 60 minutes, the contents were transferred to another container, and 3000 g of methanol was added to obtain a SG method liquid composition (sol solution). The obtained sol solution was diluted with methanol / ethylene glycol = 9/1 (mass ratio) to obtain an undercoat solution.
[0339]
<Sol solution composition>
・ Methanol 130g
・ Water 20g
・ 85% phosphoric acid 16g
・ Tetraethoxysilane 50g
・ 60 g of 3-methacryloxypropyltrimethoxysilane
[0340]
(M) Formation of heat sensitive layer
Next, a heat-sensitive layer coating solution [NL-1] having the following composition was applied to each aluminum support provided with an intermediate layer using a wire bar, and the coating amount after drying (heat-sensitive layer coating amount) was 1.3 g / m.²And dried at 115 ° C. for 45 seconds to form a heat sensitive layer (thermal negative type image recording layer) to obtain a lithographic printing plate precursor [N-1].
[0341]
<Thermosensitive layer coating solution [NL-1] composition>
-0.10 g of infrared absorber represented by the following formula
-Polymerization initiator (radical generator) represented by the following formula 0.30 g
・ Dipentaerythritol hexaacrylate 1.00g
-Copolymer of allyl methacrylate and methacrylic acid (molar ratio 80:20, weight average molecular weight 120,000) 1.00 g
・ Victoria Pure Blue Naphthalenesulfonate 0.04g
・ Fluorine-based surfactant (Megafac F-176, manufactured by Dainippon Ink & Chemicals, Inc.) 0.01 g
・ Methyl ethyl ketone 9.0g
・ Methanol 10.0g
1-methoxy-2-propanol 8.0g
[0342]
[Chemical Formula 3]

[0343]
(Examples 13 to 18 and Comparative Example 7)
In the above (m), the same method as in Examples 7 to 12 and Comparative Example 6 except that instead of the thermal layer coating solution [NL-1], a thermal layer coating solution [NL-2] having the following composition was used. Thus, a lithographic printing plate precursor [NL-2] was obtained.
[0344]
<Thermosensitive layer coating solution [NL-2] composition>
-0.10 g of infrared absorber used in the above [NL-1]
-0.15 g of acid generator (X) represented by the following formula
・ Novolak resin (weight average molecular weight 10,000) obtained from phenol and formaldehyde 1.5g
-Cross-linking agent MM-1 represented by the following formula 0.50 g
-Fluorosurfactant (Megafac F-177, manufactured by Dainippon Ink & Chemicals, Inc.) 0.03g
・ Methyl ethyl ketone 15g
・ 10 g of 1-methoxy-2-propanol
・ Methanol 5g
[0345]
[Formula 4]

[0346]
2. Evaluation of scratch resistance of lithographic printing plate precursors
The lithographic printing plate precursors [N-1] and [N-2] obtained from each support as described above were evaluated for scratch resistance.
A slip sheet was placed on the surface of the heat-sensitive layer of the lithographic printing plate precursor, and the upper and lower sides were sandwiched between corrugated cardboard sheets, which were left for 3 days in an environment of 25 ° C and 50% RH. Thereafter, the surface of the heat-sensitive layer of the lithographic printing plate precursor was rubbed 5 times with cotton gloves and exposed and developed in the same manner as in the later-described evaluation of stain resistance and printing durability to form an image. The extent to which the rubbed portion was damaged and whitened was visually observed and evaluated.
[0347]
3. Evaluation of lithographic printing plate precursor sensitivity
The lithographic printing plate precursors [N-1] and [N-2] obtained from the respective supports as described above were exposed by changing the plate surface energy amount, and were described later in terms of stain resistance and printing durability. Exposure and development were performed in the same manner as in the evaluation. Sensitivity was evaluated by the amount of plate surface energy that could form an image.
[0348]
4). Evaluation of stain resistance and printing durability of lithographic printing plate precursors
The lithographic printing plate precursors [N-1] and [N-2] obtained from the respective supports as described above are transferred to a plate material supply device (SA-L8000), an exposure device (Luxel T-9000CTP), a conveyor ( T-9000 Conveyor), automatic developing machine (LP-1310H), and stocker (ST-1160) equipped with a CTP output system manufactured by Fuji Photo Film Co., Ltd., exposed to light and developed to form an image. A printed version was obtained. Here, the first bath of the development processing tank of the automatic processor is charged with a developer mainly composed of alkali silicate (DP-4 water dilution (1: 7) manufactured by Fuji Photo Film Co., Ltd.). And kept at 30 ° C. Tap water was added to the second bath. The third bath was charged with a finishing gum solution (FP-2W water dilution (1: 1) manufactured by Fuji Photo Film Co., Ltd.).
Using the obtained lithographic printing plate, printing was performed in the same manner as in the examples for the thermal positive type lithographic printing plate precursor, and the stain resistance and printing durability were evaluated.
[0349]
The lithographic printing plate precursors of the present invention (Examples 7 to 18) using the lithographic printing plate support of the present invention are less susceptible to damage and more sensitive than the lithographic printing plate precursors of Comparative Examples 6 and 7. It was excellent.
Further, the lithographic printing plate precursors [N-1] and [N-2] of Examples 7 to 18 both had good stain resistance and excellent printing durability of 50,000 sheets or more. This is because, in a thermal negative type lithographic printing plate precursor, the image recording layer is cured by heating or irradiation to form an image portion. At this time, the surface shape of the support is the support for the lithographic printing plate of the present invention. A specific surface shape such as a body is considered to be because the adhesion between the image recording layer and the support is enhanced and the printing durability is excellent.
[0350]
<Examples of unprocessed planographic printing plate precursor>
1. Creating a lithographic printing plate precursor
A lithographic printing plate precursor was obtained in the same manner as in Examples 1 to 6 except that (h), (i) and (j) were not carried out, but the following (n) was carried out.
[0351]
(N) Formation of heat sensitive layer
Each aluminum support (lithographic printing plate support of the present invention) obtained by anodizing treatment has a coating amount (heat sensitive layer coating amount) after drying a thermosensitive layer coating liquid [ML] having the following composition: 8g / m²Then, it was coated with a wire bar and dried at 90 ° C. for 2 minutes to form a heat-sensitive layer (non-treatment type image recording layer) to obtain a lithographic printing plate precursor.
[0352]
<Coating solution for heat-sensitive layer [ML] composition>
・ 70 g of water
-5 g of microcapsules obtained in Synthesis Example (1) described later, whose outer wall is broken by heat (in terms of solid content)
・ Polyhydroxyethyl acrylate 0.5g
・ P-diazodiphenylamine sulfate 0.3g
A dispersion of ε-phthalocyanine (infrared absorber) represented by the following formula F1 0.3 g
[0353]
[Chemical formula 5]

[0354]
<Synthesis Example (1)>
As oil phase components, 40 g of xylylene diisocyanate, 10 g of trimethylolpropane diacrylate, 10 g of a copolymer of allyl methacrylate and butyl methacrylate (molar ratio 60/40) and 10 g of Pionine A41C (manufactured by Takemoto Yushi Co., Ltd.) into 60 g of ethyl acetate Dissolved. As an aqueous phase component, 120 g of a 4% aqueous solution of PVA205 (manufactured by Kuraray Co., Ltd.) was prepared. The oil phase component and the aqueous phase component were emulsified at 10,000 rpm using a homogenizer. Thereafter, 40 g of water was added, and the mixture was stirred at room temperature for 30 minutes and further at 40 ° C. for 3 hours. The solid content concentration of the microcapsule dispersion thus obtained was 20% by mass, and the average particle size of the microcapsules was 0.5 μm.
[0355]
2. Evaluation of stain resistance and printing durability of lithographic printing plate precursors
The lithographic printing plate precursor obtained from each support as described above was output using a Trendsetter 3244VFS manufactured by Creo equipped with a water-cooled 40 W infrared semiconductor laser, output 9 W, outer drum rotation speed 210 rpm, plate surface energy 100 mJ / cm.²After the exposure at a resolution of 2400 dpi, without any processing, it was attached to the cylinder of a printing machine SOR-M manufactured by Heidelberg, supplied with dampening water, supplied with ink, and further supplied with paper for printing. went.
Each lithographic printing plate precursor could be developed on-machine without problems and printed in this way. When the printed product on the 10th printed sheet was evaluated using a 20-fold magnifier, there was no background stain and the uniformity of the density of the solid image portion was extremely good. Further, when printing was continued, there was no loss of fine lines or fine characters, no solid image density unevenness, no smearing of non-image areas, and 20,000 or more excellent printed materials were obtained.
This is because, in an unprocessed negative type lithographic printing plate precursor, an image portion is formed by a mechanism such that the microcapsules of the image recording layer are torn by heating or radiation irradiation and the inclusions are discharged and cured. In this case, if the surface shape of the support is a specific surface shape like the support for a lithographic printing plate of the present invention, the outflow inclusions etc. are cured in a state of being caught on fine irregularities on the surface of the support. In addition, it is considered that the adhesion between the image recording layer and the support is enhanced and the printing durability is excellent.
[0356]
【The invention's effect】
The lithographic printing plate precursor according to the present invention is excellent in stain resistance and printing durability, and is preferably further resistant to scratches, high sensitivity, excellent printing performance, and easy to handle in normal operations. The lithographic printing plate support of the present invention is suitably used for the lithographic printing plate precursor of the present invention.
[Brief description of the drawings]
FIG. 1 is a side view showing a concept of a brush graining process used for mechanical surface roughening in the production of a lithographic printing plate support of the present invention.
FIG. 2 is a graph showing an example of an alternating waveform current waveform diagram used for electrochemical surface roughening treatment in the production of a lithographic printing plate support of the present invention.
FIG. 3 is a schematic configuration diagram of an apparatus in which two or more radial drum rollers used for electrochemical surface roughening treatment in the production of a lithographic printing plate support of the present invention are connected.
FIG. 4 is a schematic view of an anodizing apparatus for a two-stage feed electrolysis method used for anodizing in the production of a lithographic printing plate support of the present invention.
[Explanation of symbols]
1 Aluminum plate
2, 4 Roller brush
3 Polishing slurry
5, 6, 7, 8 Support roller
11 Aluminum plate
12 Radial drum roller
13a, 13b Main pole
14 Electrolytic treatment liquid
15 Electrolyte supply port
16 slits
17 Electrolyte passage
18 Auxiliary anode
19a, 19b Thyristor
20 AC power supply
40, 41 Main electrolytic cell
50, 51 Auxiliary anode tank
62a First feeding part
62b Second feeding part
63a First electrolysis part
63b Second electrolysis unit
64a, 64b Nip roller
65a First feeding electrode
65b Second feeding electrode
66a, 66b, 66c, 66d Electrolytic electrode
67a, 67b, 67c, 67d Power supply

Claims (2)

A lithographic printing plate precursor provided with an image recording layer on a lithographic printing plate support obtained by subjecting an aluminum plate to roughening treatment, alkali etching treatment and anodizing treatment,
On the surface of the lithographic printing plate support, a large wave structure with a wavelength of 2 to 10 μm , a medium wave structure composed of pits with an average diameter of 0.1 to 1.5 μm, and an equivalent area circle diameter of 0. An anodized film having a small wave structure composed of irregularities of 005 to 0.1 μm and generated by the anodizing treatment, the average pore diameter of micropores is 0 to 15 nm, and the average pore density is 0 to 400 / Μm ²
A lithographic printing plate precursor wherein the image recording layer is a thermal positive layer of any one of a thermal positive type, a thermal negative type and an untreated type. The lithographic printing plate precursor according to claim 1, wherein a content of Cu in the aluminum plate is 0 to 0.005 mass%.

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