JP2005035034A - Method for manufacturing support for lithographic printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an original plate for a lithographic printing plate for which a raw material aluminum obtained from a used beverage can can be enough utilized, and which is excellent in stain resistance, printing wear resistance, sensitivity and shiny properties, and which satisfies industrial productivity with an inexpensive raw material, a simple process, and a decreased burden to the environment. <P>SOLUTION: In a method for manufacturing a support for the lithographic printing plate, an aluminum sheet whose composition comprises 0.3-1 mass% Fe, 0.15-1 mass% Si, 0.1-1 mass% Cu, 0.1-1.5 mass% Mg, 0.1-1.5 mass% Mn, 0.1-1.5 mass% Zn, 0.01-0.1 mass% Cr, 0.01-0.5 mass% Ti and 99.4-95 mass% Al, and having an uneven pattern formed on the surface by transfer, is roughened. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０１８８】
３．平版印刷版用支持体の作製
＜支持体実施例１〜３および支持体比較例１＞
得られた各アルミニウム板を以下に示す表面処理に供して、平版印刷版用支持体１〜６および比較支持体１を得た。
＜表面処理＞
表面処理は、以下の（ａ）〜（ｊ）の各種処理を連続的に行うことにより行った。
【０１８９】
（ａ）アルカリ水溶液中でのエッチング処理（第一）
アルミニウム板に、カセイソーダ濃度３７０ｇ／Ｌ、アルミニウムイオン濃度１００ｇ／Ｌ、温度６０℃の水溶液をスプレー管から吹き付けて、エッチング処理を行った。アルミニウム板の後に電気化学的粗面化処理を施す面のエッチング量は、３ｇ／ｍ^２ であった。
その後、ニップローラで液切りし、更に、後述する水洗処理を行った後、ニップローラで液切りした。水洗処理は、図 １に示す自由落下カーテン状の液膜により水洗処理する装置を用いて水洗し、更に、扇状に噴射水が広がるスプレーチップを８０ｍｍ間隔で有する構造を有するスプレー管を用いて５秒間水洗処理した。
【０１９０】
（ｂ）酸性水溶液中でのデスマット処理（第一）
温度３５℃の硝酸水溶液をスプレー管から５秒間吹き付けて、デスマット処理を行った。硝酸水溶液としては、後述する（ｃ）硝酸水溶液中での交流を用いた電気化学的粗面化処理工程の廃液を用いた。
その後、ニップローラによる液切りを行わずに、アルミニウム板に硝酸水溶液が付着している状態で搬送した。搬送時間は２５秒間であった。
【０１９１】
（ｃ）硝酸水溶液中での交流を用いた電気化学的粗面化処理（第一電解処理）
電気化学的粗面化処理を行う直前に、アルミニウム板に、後述する硝酸電解に用いた電解液と同じ組成および温度を有する電解液を吹き付けた。
その後、１１．０ｇ／Ｌ硝酸水溶液に硝酸アルミニウムを溶解させてアルミニウムイオン濃度を４．５ｇ／Ｌとした電解液（液温５０℃）を用い、６０Ｈｚの交流電圧を用いて連続的に電気化学的粗面化処理を行った。交流電源波形は図２に示した波形であり、電流値がゼロからピークに達するまでの時間ＴＰが０．８ｍｓｅｃ、ｄｕｔｙ比（ｔａ／Ｔ）０．５であった。カーボン電極を対極として用いた。補助アノードにはフェライトを用いた。電解槽は図３に示すものを２槽使用した。
電気化学的粗面化処理において、交流のピーク時におけるアルミニウム板のアノード反応時の電流密度は、６０Ａ／ｄｍ^２ であった。アルミニウム板のアノード反応時の電気量の総和とカソード反応時の電気量の総和との比は０．９５であった。電気量はアルミニウム板のアノード時の電気量の総和で２００Ｃ／ｄｍ^２ であった。補助陽極には電源から流れる電流の５％を分流させた。アルミニウム板と電解液の相対速度は、電解槽内の平均で１．５ｍ／ｓｅｃであった。
その後、ニップローラで液切りし、更に、上記（ａ）の水洗処理に用いたのと同様の構造のスプレー管を用いて水洗処理を行った後、ニップローラで液切りした。
【０１９２】
（ｄ）アルカリ水溶液中でのエッチング処理（第二）
アルミニウム板を、カセイソーダ濃度３７０ｇ／Ｌ、アルミニウムイオン濃度１００ｇ／Ｌ、温度６４℃の水溶液をスプレー管から吹き付けて、７秒間エッチング処理を行った。後の工程で電気化学的粗面化処理する面のエッチング量は３ｇ／ｍ^２ であった。
その後、ニップローラで液切りし、更に、後述する水洗処理を行った後、ニップローラで液切りした。水洗処理は、自由落下カーテン状の液膜により水洗処理する装置を用いて水洗し、更に、上記（ａ）の水洗処理に用いたのと同様の構造のスプレー管を用いて５秒間水洗することにより行った。
【０１９３】
（ｅ）酸性水溶液中でのデスマット処理（第二）
硫酸３００ｇ／Ｌ水溶液に硝酸アルミニウムを溶解させてアルミニウムイオン濃度を２ｇ／Ｌとした水溶液（液温３５℃）をスプレー管から１０秒間吹き付けて、デスマット処理を行った。
その後、ニップローラで液切りし、水洗し、さらにニップローラで液切りした。
【０１９４】
（ｆ）塩酸水溶液中での交流を用いた電気化学的粗面化処理（第二電解処理）
液温３５℃、塩酸濃度５ｇ／Ｌの水溶液に、塩化アルミニウムを溶解させてアルミニウムイオン濃度を５ｇ／Ｌとした電解液を用い、台形波交流電流を発生する電源を用いて６０Ｈｚの周波数を用いて連続的に電気化学的粗面化処理を行った。電流値がゼロからピークに達するまでの時間ＴＰが０．８ｍｓｅｃ、ｄｕｔｙ比（ｔａ／Ｔ）０．５であった。カーボン電極を対極として用いた。補助アノードにはフェライトを用いた。電解槽は図３に示すものを１槽使用した。
電気化学的粗面化処理において、交流のピーク時におけるアルミニウム板のアノード反応時の電流密度は、５０Ａ／ｄｍ^２ であった。アルミニウム板のアノード反応時の電気量の総和とカソード反応時の電気量の総和との比は０．９５であった。電気量はアルミニウム板のアノード時の電気量の総和で６３Ｃ／ｄｍ^２ であった。補助陽極には電源から流れる電流の５％を分流させた。アルミニウム板と電解液の相対速度は、電解槽内の平均で１．５ｍ／ｓｅｃであった。
その後、ニップローラで液切りし、水洗し、更にニップローラで液切りした。
【０１９５】
（ｇ）アルカリ水溶液中でのエッチング処理（第三）
アルミニウム板に、カセイソーダ濃度５０ｇ／Ｌ、アルミニウムイオン濃度５ｇ／Ｌ、温度３５℃の水溶液をスプレー管から吹き付けて、エッチング処理を行った。アルミニウム板の電気化学的粗面化処理を施した面のエッチング量は、０．１ｇ／ｍ^２ であった。
その後、ニップローラで液切りし、更に、後述する水洗処理を行った後、ニップローラで液切りした。水洗処理は、自由落下カーテン状の液膜により水洗処理する装置を用いて水洗し、更に、上記（ａ）の水洗処理に用いたのと同様の構造のスプレー管を用いて５秒間水洗することにより行った。
【０１９６】
（ｈ）酸性水溶液中でのデスマット処理（第三）
水溶液としては、後述する（ｉ）陽極酸化処理の廃液（硫酸濃度１７０ｇ／Ｌ、アルミニウムイオン濃度５ｇ／Ｌ、液温３５℃）を用いて、スプレー管から５秒間吹き付けて、デスマット処理を行った。
その後、ニップローラで液切りしたが、ニップローラーで液切り後、陽極酸化するまでは水洗処理は行わなかった。
【０１９７】
（ｉ）陽極酸化処理
図４に示される陽極酸化処理装置を用いて陽極酸化処理を行った。
電解液としては、１７０ｇ／Ｌ硫酸水溶液に硫酸アルミニウムを溶解させてアルミニウムイオン濃度を５ｇ／Ｌとした電解液（温度３３℃）を用いた。陽極酸化処理は、アルミニウム板がアノード反応する間（約１６秒）の平均電流密度が１５Ａ／ｄｍ^２ となるように行い、最終的な酸化皮膜量は２．４ｇ／ｍ^２ であった。なお、アルミニウム板がアノード反応にあずかる時間は１６秒であった。
その後、ニップローラで液切りし、水洗し、更にニップローラで液切りした。
【０１９８】
（ｊ）親水化処理
アルミニウム板をケイ酸ソーダ２．５質量％水溶液（液温２０℃）に１０秒間浸せきさせた。蛍光Ｘ線分析装置で測定したアルミニウム板表面のＳｉ量は、３．５ｍｇ／ｍ^２ であった。
その後、ニップローラで液切りし、水洗し、更にニップローラで液切りした。更に、９０℃の風を１０秒間吹き付けて乾燥させて、平版印刷版用支持体実施例１〜３を得た。
【０１９９】
＜支持体実施例４＞
支持体実施例 １で用いたアルミニウム板を用い、上記粗面化処理（ａ）〜（ｄ）の条件を以下の条件に変えた以外は、支持体実施例１と同様にして、平版印刷版用支持体４を得た。
（ａ−２）アルカリ水溶液中でのエッチング処理（第一）
上記（ａ） の条件のうち、アルミニウム板の後に電気化学的粗面化処理を施す面のエッチング量を、２ｇ／ｍ^２ とした以外は、（ａ）アルカリ水溶液中でのエッチング処理（第一）と同様の処理をした。
【０２００】
（ｂ−２）酸性水溶液中でのデスマット処理（第一）
上記（ｂ） の条件のうち、最後の搬送時間が１０秒間であった以外は、（ｂ）酸性水溶液中でのデスマット処理（第一）と同様の処理をした。
【０２０１】
（ｃ−２）塩酸水溶液中での交流を用いた電気化学的粗面化処理（第一電解処理）
上記（ｃ）では、硝酸水溶液中での電気化学的粗面化処理を行ったが、支持体実施例４では以下の条件の塩酸水溶液中での交流を用いた電気化学的粗面化処理を第一電解処理として行った。
液温３５℃、塩酸濃度７．５ｇ／Ｌの水溶液に、塩化アルミニウムを溶解させてアルミニウムイオン濃度を４．５ｇ／Ｌとした電解液を用い、サイン波交流電流を発生する電源を用いて５０Ｈｚの周波数を用いて連続的に電気化学的粗面化処理を行った。ｄｕｔｙ比（ｔａ／Ｔ）０．５であった。カーボン電極を対極として用いた。補助アノードにはフェライトを用いた。電解槽は図３に示すものを２槽使用した。
電気化学的粗面化処理において、交流のピーク時におけるアルミニウム板のアノード反応時の電流密度は、６０Ａ／ｄｍ^２ であった。アルミニウム板のアノード反応時の電気量の総和とカソード反応時の電気量の総和との比は０．９５であった。電気量はアルミニウム板のアノード時の電気量の総和で２５０Ｃ／ｄｍ^２ であった。補助陽極には電源から流れる電流の５％を分流させた。アルミニウム板と電解液の相対速度は、電解槽内の平均で１．５ｍ／ｓｅｃ（１〜２ｍ／ｓｅｃ）であった。
その後、ニップローラで液切りし、水洗し、更にニップローラで液切りした。
【０２０２】
（ｄ−２） アルカリ水溶液中でのエッチング処理（第二）
上記（ｄ）の条件のうち後の工程で電気化学的粗面化処理する面のエッチング量を１ｇ／ｍ^２ とした以外は、（ｄ）アルカリ水溶液中でのエッチング処理（第二）と同様の処理をした。
【０２０３】
＜支持体実施例５＞
支持体実施例１と同様の組成および凹凸パターンを有するアルミニウム板を用い、支持体実施例１の（ａ）アルカリ水溶液中でのエッチング処理（第一）の前に、以下の（ｋ）機械的粗面化処理を行った。 （ａ）〜（ｊ）の表面処理は， 支持体実施例１と同様に行い、その後同様に乾燥して平版印刷版用支持体５を製造した。
【０２０４】
（ｋ）ブラシと研磨剤を用いる機械的粗面化処理
比重１．１３のパミストン（平均粒径３０μｍ）を水に懸濁させた懸濁液を研磨スラリー液として用い、回転ブラシを１ 本とし、粗面化後のＲａが０．５８μｍとなるようにブラシ回転数２５０ｒｐｍで機械的粗面化を行なった。
【０２０５】
ローラ状ブラシとしては、毛長５０ｍｍ、毛の直径０．２９５ｍｍの６・１０ナイロンの毛を、直径３００ｍｍのステンレス鋼製ローラの表面に孔を開けて密になるように植設したものを用いた。
ブラシ下部の２本の支持ローラは、直径２００ｍｍのステンレス鋼製ローラをの中心間の距離３００ｍｍで用いた。
【０２０６】
ローラ状ブラシは、ブラシを回転させる駆動モータの負荷がブラシローラをアルミニウム板に押さえつける前の負荷に対して７ｋｗプラスになる圧力で押し付け、粗面化面における回転方向がアルミニウムウェブＷの搬送方向と同方向になるように回転させた。
【０２０７】
研磨材スラリーの温度と比重とから研磨材の濃度を連続的に求め、濃度が一定になるように、水およびパミストンをスラリー回収槽に補充しつつ、機械的粗面化を行なった。また、機械的粗面化において粉砕され、細粒化したパミストンは、粒子径調整部における分級器で除去し、前記研磨材スラリー中のパミストンの粒度分布がほぼ一定になるようにした。なお、分級器としては、サイクロンを用いた。
【０２０８】
＜支持体実施例６＞
支持体実施例４と同様の組成および凹凸パターンを有するアルミニウム板を用い、支持体実施例４の（ａ−２）アルカリ水溶液中でのエッチング処理（第一）の前に、上記の（ｋ）機械的粗面化処理を粗面化後のＲａが０．５８μｍとなるように同様に行った。 （ａ−２）〜（ｄ−２）〜（ｅ）〜（ｊ）の表面処理は， 支持体実施例４と同様に行い、その後同様に乾燥して平版印刷版用支持体６を製造した。
【０２０９】
＜支持体比較例１＞
ＪＩＳ Ａ １０５０の組成のアルミニウムを用い、支持体実施例１と同様に、冷間圧延の最終圧延時に支持体実施例１と同様の凹凸パターンを転写した。その後、厚さ０．３ｍｍ、幅１０６０ｍｍの比較アルミニウム板１に仕上げ、支持体実施例１と同様に粗面化処理（ａ）〜（ｊ）を行なって、比較平版印刷版用支持体１を得た。
【０２１０】
＜支持体比較例２＞
支持体実施例５と同様に、ただし、凹凸パターンを転写せず、（ｋ）機械的粗面化処理のみで機械的粗面化後のＲａが０．５８μｍとなるように処理したアルミニウム板を、支持体実施例５と同様に粗面化処理（ａ）〜（ｊ）を行なって、比較平版印刷版用支持体２を得た。
【０２１１】
４． 平版印刷版用支持体の評価
（１）表面形状
得られた平版印刷版用支持体１〜６、および比較支持体１〜２の表面形状を走査型電子顕微鏡（ＪＳＭ−５５００、日本電子社製。以下同じ。）で倍率５００００倍で観察したところ、その表面に直径０．１μｍの微細な凹凸が均一かつ緻密に生成していた。また、走査型電子顕微鏡で倍率２０００倍で観察したところ、このアルミニウム板の表面には直径１〜５μｍの凹凸が生成していた。この直径０．１μｍの微細な凹凸は直径１〜５μｍの凹凸に重畳して生成していた。
なお、比較支持体２の表面形状は、その表面に直径０．１μｍの微細な凹凸が均一かつ緻密に生成していた。また、このアルミニウム板の表面には直径１〜 １５μｍの凹凸が生成していた。この直径０．１μｍの微細な凹凸は前記直径１〜１５μｍの凹凸に重畳して生成していた。
【０２１２】
（２）平版印刷版用支持体の表面のチャタマークの観察（支持体処理ムラ）
各平版印刷版用支持体の表面を肉眼で観察し、チャタマークの程度を官能評価した。結果を第２表に示す。表中、チャタマークがなかったものをＡ、ほとんどなかったものをＡ−Ｂ、あったが問題ない程度であったものをＢ、はっきりあったものをＣとした。
【０２１３】
５．平版印刷版原版の作製
上記で得られた各平版印刷版用支持体１〜６、比較支持体１〜２に、以下のようにしてサーマルポジタイプの画像記録層を設けて平版印刷版原版（実施例１〜６、比較例１、２）を得た。なお、画像記録層を設ける前には、後述するように下塗層を設けた。
【０２１４】
平版印刷版用支持体上に、下記組成の下塗液を塗布し、８０℃で１５秒間乾燥し、下塗層の塗膜を形成させた。乾燥後の塗膜の被覆量は１５ｍｇ／ｍ^２ であった。
【０２１５】
＜下塗液組成＞
・下記高分子化合物 ０．３ｇ
・メタノール １００ｇ
・水 １ｇ
【０２１６】
【化１】

【０２１７】
更に、下記組成の感熱層塗布液を調製し、下塗層を設けた平版印刷版用支持体に、この感熱層塗布液を乾燥後の塗布量（感熱層塗布量）が１．８ｇ／ｍ^２ になるよう塗布し、乾燥させて感熱層（サーマルポジタイプの画像記録層）を形成させ、平版印刷版原版を得た。
【０２１８】
＜感熱層塗布液組成＞
・ノボラック樹脂（ｍ−クレゾール／ｐ−クレゾール＝６０／４０、重量平均分子量７，０００、未反応クレゾール０．５質量％含有） ０．９０ｇ
・メタクリル酸エチル／メタクリル酸イソブチル／メタクリル酸共重合体（モル比３５／３５／３０） ０．１０ｇ
・下記構造式で表されるシアニン染料Ａ ０．１ｇ
・テトラヒドロ無水フタル酸 ０．０５ｇ
・ｐ−トルエンスルホン酸 ０．００２ｇ
・エチルバイオレットの対イオンを６−ヒドロキシ−β−ナフタレンスルホン酸にしたもの ０．０２ｇ
・フッ素系界面活性剤（ディフェンサＦ−７８０Ｆ、大日本インキ化学工業社製、固形分３０質量％） ０．００４５ｇ（固形分換算）
・フッ素系界面活性剤（ディフェンサＦ−７８１Ｆ、大日本インキ化学工業社製、固形分１００質量％） ０．０３５ｇ
・メチルエチルケトン １２ｇ
【０２１９】
【化２】

【０２２０】
６．平版印刷版原版の評価
平版印刷版の耐刷性、耐汚れ性、感度および水量の調節のしやすさ（シャイニー）を下記の方法で評価した。
（１）耐刷性
得られた平版印刷版原版をＣｒｅｏ社製ＴｒｅｎｄＳｅｔｔｅｒを用いてドラム回転速度１５０ｒｐｍ、ビーム強度１０Ｗで画像状に描き込みを行った。
その後、下記組成のアルカリ現像液を仕込んだ富士写真フイルム（株）製ＰＳプロセッサー９４０Ｈを用い、液温を３０℃に保ち、現像時間２０秒で現像し、平版印刷版を得た。
【０２２１】
＜アルカリ現像液組成＞
・Ｄ−ソルビット ２．５質量％
・水酸化ナトリウム ０．８５質量％
・ポリエチレングリコールラウリルエーテル（重量平均分子量１，０００）
０．５ 質量％
・水 ９６．１５質量％
【０２２２】
得られた平版印刷版を、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。
結果を第２表に示す。第２表中、以下で評価した。
Ａ：印刷枚数が、３万枚以上
Ｂ：印刷枚数が、３万枚未満、２万枚以上
Ｃ：印刷枚数が、２万枚未満
【０２２３】
（２）感度
平版印刷版原版を出力５００ｍＷ、波長８３０ｎｍ、ビーム径１７μｍ（１／ｅ^２ ）の半導体レーザを装備したＣＲＥＯ社製ＴｒｅｎｄＳｅｔｔｅｒ３２４４を用いて主走査速度５ｍ／秒、版面エネルギー量１４０ｍＪ／ｃｍ^２ で像様露光した。感度の評価のためには、版面エネルギー量を４５〜１８０ｍＪ／ｃｍ^２ まで５ｍＪ／ｃｍ^２ おきに変えて露光を行ったサンプルを準備した。
現像処理は、下記組成の現像液Ｂ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。版面エネルギー量を変化させたサンプルから、現像処理後画像形成できた最低露光量を感度とした。
結果は第１表に示した。 第２表中、以下で評価した。
Ａ：エネルギー量（ｍＪ／ｃｍ^２）、１００ｍＪ／ｃｍ^２未満であり
Ｂ：エネルギー量１５０ｍＪ／ｃｍ^２未満、１００ｍＪ／ｃｍ^２以上、
Ｃ：エネルギー量１５０ｍＪ／ｃｍ^２以上。
【０２２４】
（３）耐汚れ性
上記（１）耐刷性の評価と同様にして得られた平版印刷版を用い、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。
結果を第２表に示す。第２表中、以下で評価した。
Ａ：ブランケットがほとんど汚れていないもの
Ｂ：ブランケットが少し汚れていたもの
Ｂ−Ｃ：ブランケットが汚れているものの許容できる範囲にあるもの
Ｃ：ブランケットが汚れており印刷物が明らかに汚れているもの
【０２２５】
（４）シャイニー
上記（１）耐刷性の評価と同様にして得られた平版印刷版を、小森コーポレーション社製のリスロン印刷機に取り付け、湿し水の供給量を増加させながら版面の非画像部の光り具合を目視で観察し、光り始めたときの湿し水の供給量でシャイニー性（検版性：水上がりの見やすさ）を評価した。その結果を第２表に示す。
光り始めたときの湿し水量が多いものから少ないものまでを順に、
Ａ、Ａ−Ｂ、Ｂ、Ｂ−Ｃ、Ｃの５段階で評価した。
【０２２６】
【表２】

【０２２７】
第２表から明らかなように、本発明の平版印刷版用支持体の製造方法（支持体実施例１〜４）により得られた平版印刷版用支持体を用いた平版印刷版は、いずれも耐刷性、耐汚れ性、感度およびシャイニーに優れていた。
さらに、凹凸パターンの形成後にブラシと研磨剤を用いた機械的粗面化処理をさらに行った平版印刷版用支持体５と６を用いて製造した平版印刷版原版の実施例５と実施例６は、それぞれ、当該機械的粗面化処理を行わない平版印刷版用支持体１と２を用いて製造した平版印刷版原版の実施例１と実施例４に比較して更に面質が均一で良好な印刷版が得られた。
【０２２８】
【発明の効果】
以上に説明したように、本発明によれば、平版印刷版としたときの耐汚れ性、耐刷性、感度およびシャイニーのいずれにも優れ、工業的生産性をも満足する平版印刷版原版に用いられる平版印刷版用支持体が得られる。
【図面の簡単な説明】
【図１】本発明の平版印刷版用支持体の製造方法における水洗処理に用いられる自由落下カーテン状の液膜により水洗処理する装置の模式的な断面図である。
【図２】本発明の平版印刷版用支持体の製造方法における電気化学的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製造方法における交流を用いた電気化学的粗面化処理におけるラジアル型セルの一例を示す側面図である。
【図４】本発明の平版印刷版用支持体の製造方法における陽極酸化処理に用いられる陽極酸化処理装置の概略図である。
【図５】本発明の平版印刷版用支持体の製造方法における電気化学的粗面化処理に用いられるサイン波形図の一例を示すグラフである。
【図６】本発明の平版印刷版用支持体の製造方法における直流を用いた電気化学的粗面化処理に用いられる装置の一例を示す側面図である。
【図７】本発明の平版印刷版用支持体の製造方法における直流を用いた電気化学的粗面化処理に用いられる装置の別の一例を示す側面図である。
【符号の説明】
１ アルミニウム板
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 主電解槽
５０ 補助陽極槽
６１ アルミニウム板
６２ 陽極
６３ 陰極
６４ 電解液
６５ 電解槽
６６ 供液ノズル
６７ 排液管
６８ 供液管
１００ 自由落下カーテン状の液膜により水洗処理する装置
１０２ 水
１０４ 貯水タンク
１０６ 給水筒
１０８ 整流部
４１０ 陽極酸化処理装置
４１２ 給電槽
４１３ 中間槽
４１４ 陽極酸化処理槽
４１６ アルミニウム板
４１８、４２６ 電解液
４２０ 陽極
４２２、４２８ パスローラ
４２４ ニップローラ
４３０ 陰極
４３４ 直流電源
４３６、４３８ 給液ノズル
４４０ しゃへい板
４４２ 排液口[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a lithographic printing plate support. Specifically, a method for producing a support for a lithographic printing plate used for a lithographic printing plate precursor having reduced environmental burden, excellent printing performance, printing durability, sensitivity and shiny, and satisfying industrial productivity. About.
[0002]
[Prior art]
An aluminum support for a lithographic printing plate (hereinafter simply referred to as “support for a lithographic printing plate”) used in a lithographic printing plate is produced by subjecting an aluminum plate to a surface roughening treatment or other surface treatment. Examples of the roughening treatment include mechanical roughening treatment, electrochemical roughening treatment (hereinafter also referred to as “electrolytic roughening treatment”), and chemical roughening treatment (chemical etching). A method combining these is known.
Among these, the mechanical surface roughening treatment is effective for improving the printing durability of the lithographic printing plate. As a mechanical surface roughening treatment, a method of spraying an abrasive slurry between a rotating nylon brush and an aluminum plate is generally known.
However, this method using a nylon brush and an abrasive has the advantage that it can be carried out at a high speed and at a low cost. On the other hand, it is difficult to control the particle size of the abrasive. Deep recesses are easily generated. As a result, if there are locally deep recesses on the surface of the lithographic printing plate support, it is difficult for the lithographic printing plate provided with a positive image recording layer to develop locally deep portions of the non-image area. Problems arise. Further, in the planographic printing plate provided with the negative type image recording layer, there is a problem that a locally deep portion of the image portion is difficult to be formed as an image.
In addition, since the method using a nylon brush and an abrasive physically roughens, a sharpened portion is generated. Therefore, in order to smooth the portion, a large amount of aluminum is added by an alkali etching treatment in a later step. Must be dissolved. Therefore, there is a problem that the cost is high and the load on the environment is large.
[0003]
As a lithographic printing plate support that can solve these problems, after cold rolling to adjust the final plate thickness by continuous casting, instead of mechanical roughening using a brush and an abrasive, or after final plate thickness adjustment A lithographic printing plate support or the like in which an uneven surface is pressed and transferred to an aluminum plate together with finish cold rolling to finish the surface shape and an uneven pattern is formed on the surface of the aluminum plate is known (see Patent Document 1). .
Also, a method for producing a support for a lithographic printing plate precursor by performing a specific surface treatment is described, and it is described in the specification that an aluminum plate having a UCB composition can also be used. In the examples, an aluminum plate of JIS 3004 is used. There is a conventional technique in which an example is described (see Patent Document 2).
[0004]
However, in these manufacturing methods, since the aluminum plate becomes hard when the purity of the aluminum plate is lowered, the mechanical surface roughening treatment with a nylon brush and an abrasive requires more energy than the conventional aluminum plate. Further, if the hard aluminum plate is forcibly roughened, deep recesses are locally formed, resulting in poor sensitivity.
Therefore, a support capable of obtaining a lithographic printing plate that is excellent in printing durability, stain resistance, sensitivity and shiny printing performance and satisfies industrial productivity has not been obtained.
[0005]
By the way, generally in printing using a lithographic printing plate, it is necessary to adjust the amount of dampening water (water amount) during printing. However, if there is too much light reflection on the plate surface, Since adjustment becomes difficult, the case where dirt occurs may occur. Therefore, it is necessary to suppress the light reflection to a certain level on the surface of the lithographic printing plate support, which is a non-image part of the lithographic printing plate. However, the amount of light reflection increases, and even with a small amount of water, When attached to the plate, the printing plate may shine. Such a phenomenon is called “shiny” and is an undesirable phenomenon from the viewpoint of confirming the adjustment of the amount of water (plate inspection), and improvement is also desired.
[0006]
[Patent Document 1]
JP-A-6-262203
[Patent Document 2]
JP 2003-39846 A
[0007]
[Problems to be solved by the invention]
As described above, in order to reduce environmental burden and provide inexpensive industrial products, even when using raw material aluminum obtained from used drinking cans, such as stain resistance, printing durability, sensitivity, and shiny There is a need for a method for producing a lithographic printing plate support that provides a lithographic printing plate precursor that satisfies printing performance and that can be produced with ease.
[0008]
[Means for Solving the Problems]
As a result of diligent research to achieve the above object, the present inventors have performed a roughening treatment on an aluminum plate having a specific composition and having a concavo-convex pattern formed on the surface of the aluminum plate by transfer, Mechanical roughening treatment (hereinafter sometimes referred to as brush grain treatment) using a rotating brush and an abrasive is not performed, or the conditions for brush grain treatment can be weakened, causing problems in brush grain treatment. The raw material aluminum obtained from used drinking cans is fully utilized, and it is excellent in all of stain resistance, printing durability, sensitivity and shiny, the raw material is inexpensive and the process is It was found that a lithographic printing plate precursor satisfying industrial productivity that is simple and capable of reducing the burden on the environment was obtained, and the present invention was completed.
[0009]
In the present invention, “the load on the environment is reduced” means that aluminum having an aluminum plate composition of 95 to 99.4% by mass is used. Used Beverage Can (used beverage cans, sometimes referred to as UBC) can be used as the raw material aluminum, can promote the recycling of metal materials, and can perform mechanical surface roughening using a nylon brush and an abrasive. It means that waste liquid treatment can be reduced because it can be omitted or reduced. “Satisfying industrial productivity” means that the manufacturing process can be simplified and the manufacturing energy can be reduced, so that low-cost products required by consumers can be provided, and industrially energy-saving, resource-saving, and manpower-saving. Say what you can achieve.
[0010]
That is, the present invention provides the following (1) to (6).
(1) Composition: Fe: 0.3-1 mass%, Si: 0.15-1 mass%, Cu: 0.1-1 mass%, Mg: 0.1-1.5 mass%, Mn: 0.1 to 1.5 mass%, Zn: 0.1 to 1.5 mass%, Cr: 0.01 to 0.1 mass%, Ti: 0.01 to 0.5 mass%, Al: 99. An aluminum plate that is 4 to 95% by mass,
A method for producing a lithographic printing plate support, comprising roughening an aluminum plate having a concavo-convex pattern formed on a surface by transfer.
[0011]
(2) Manufacture of a support for a lithographic printing plate for roughening an aluminum plate having a concavo-convex pattern formed on the surface by transfer, obtained from a used metal beverage can (Used BeverageCan) Method.
(3) An aluminum plate having a concavo-convex pattern formed on the surface by the transfer directly produces a thin plate by continuous casting, and cold rolling to adjust the final plate thickness in the steps of annealing, cold rolling, and correction, Or, in the above (1) or (2), which is an aluminum plate in which a concavo-convex pattern is formed on the surface of the aluminum plate by pressing and transferring the concavo-convex surface to the aluminum plate together with finish cold rolling to finish the surface shape after final thickness adjustment The manufacturing method of the support for lithographic printing plates of description.
[0012]
(4) The roughening treatment is performed in order,
Etching treatment in alkaline solution,
Desmut treatment in acidic aqueous solution,
Electrochemical roughening treatment in aqueous solution containing nitric acid or hydrochloric acid,
Etching treatment in alkaline solution,
Desmut treatment in acidic aqueous solution,
Electrochemical roughening treatment in an aqueous solution containing hydrochloric acid,
Etching treatment in alkaline solution,
Desmutting in acidic aqueous solution, and
The method for producing a lithographic printing plate support according to any one of the above (1) to (3), which is anodized.
[0013]
(5) The method for producing a lithographic printing plate support according to (4), wherein the hydrophilization treatment is performed after the anodizing treatment.
(6) A lithographic printing plate precursor having a recording layer on a lithographic printing plate support obtained by the production method of any one of (1) to (5) above.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
[0015]
[Method for producing support for lithographic printing plate]
<Aluminum plate (rolled aluminum)>
An aluminum plate having a specific composition is used in the method for producing a lithographic printing plate support of the present invention. The aluminum plate used in the present invention is an alloy plate mainly composed of dimensionally stable aluminum.
The composition of the aluminum material used for the aluminum plate of the present invention is as follows: Fe: 0.3-1 mass%, Si: 0.15-1 mass%, Cu: 0.1-1 mass%, Mg: 0.1-1 0.5% by mass, Mn: 0.1-1.5% by mass, Zn: 0.1-1.5% by mass, Cr: 0.01-0.1% by mass, Ti: 0.01-0.5% It is an aluminum plate of mass%, Al: 99.4 to 95 mass%.
[0016]
Generally, the foreign elements that may be contained in the aluminum plate include, for example, silicon, iron, copper, titanium, gallium, vanadium, zinc, chromium, zirconium, barium, cobalt, etc., and the content of the foreign elements in the alloy Is 10% by mass or less.
Examples of inevitable impurities contained in the aluminum alloy include lead, nickel, tin, indium, and boron.
[0017]
Preferably, the Fe content is more than 0.30 to 0.70 mass%, the Si content is 0.20 to 0.50 mass%, the Cu content is 0.10 to 0.50 mass%, and the Ti content is 0.02-0.3 mass%, Mg content is 0.50-1.5 mass%, Mn content is 0.1-1.3 mass%, and Cr content is 0.01-0. 08 mass%, Zn content is 0.1-1. An aluminum plate having 3% by mass and the balance of 95 to 99.4% by mass of Al and unavoidable impurities is used.
[0018]
The different elements in the aluminum plate greatly depend on the uniformity of the pits generated in the electrochemical surface roughening treatment, and uniform pits are generated by adjusting the type and addition amount of the different elements. Stainability and exposure stability can be achieved with a high level of balance.
Moreover, the aluminum plate obtained by rolling a bullion in which the used aluminum beverage can was dissolved (Used Beverage Can, used beverage can) can also be used suitably.
[0019]
More preferably, Fe content is more than 0.40 to 0.50% by mass, Si content is more than 0.25 to 0.30% by mass, Cu content is 0.10 to 0.15% by mass, Ti content is contained. The amount is 0.02-0.05 mass%, the Mg content is 0.80-1.5 mass%, the Mn content is 0.10-1.00 mass%, and the Cr content is 0.01- An aluminum plate having 0.05% by mass, Zn content of 0.1 to 0.3% by mass and the balance of Al content of 95 to 99.4% by mass and inevitable impurities is used.
[0020]
Fe is an element contained in a new metal in the range of about 0.1 to 0.2% by mass, and the amount dissolved in aluminum is small, and most remains as an intermetallic compound. Fe has an effect of increasing the mechanical strength of the aluminum plate. However, if it is more than 1% by mass, cracking is likely to occur during rolling, and if the Fe content is less than 0.15% by mass, the mechanical strength is low. As a result, problems such as a decrease in yield may occur during rolling.
In this invention, Fe content is 0.3-1 mass%. Preferably, it is more than 0.30 to 0.70% by mass, and more preferably more than 0.30 to 0.50% by mass.
[0021]
Si is an element contained in the new metal also in the range of about 0.02 to 0.1% by mass. Si exists as a solid solution in aluminum, or as an intermetallic compound or a single precipitate. In addition, when heated in the process of producing a lithographic printing plate support, the dissolved Si may precipitate as elemental Si. According to the knowledge of the present inventors, when the elemental Si is excessive, the solid solution Si is likely to precipitate as the elemental Si, and the severe ink stain resistance may be lowered.
Further, the Si content affects the electrochemical surface roughening of the aluminum plate, and if it is less than 0.03% by mass, the pits may be dissolved in the electrochemical surface roughening treatment and a uniform surface structure may not be obtained. .
In the present invention, the Si content is 0.15 to 1% by mass. Preferably it is 0.20 to 0.50 mass%, More preferably, it is more than 0.20 to 0.40 mass%.
[0022]
Cu is an element contained in a lot of scraps of JIS 2000 series and 4000 series materials, and is relatively easily dissolved in Al.
The Cu content greatly affects the electrochemical roughening treatment. In particular, in an electrochemical surface roughening treatment using alternating current in an electrolytic solution containing nitric acid (hereinafter simply referred to as “nitric acid alternating current electrolysis”), if the Cu content is less than 0.0001% by mass, electrolysis is performed. The latitude may become narrower with respect to temperature fluctuations.
Content of Cu is 0.1-1 mass%. Preferably, it is 0.10 to 0.50 mass%, More preferably, it is 0.10 to 0.30 mass%.
[0023]
Ti is an element that is usually added in an amount of 0.005 to 0.04 mass% as a crystal refining material. JIS 5000 series, 6000 series, and 7000 series scraps contain relatively large amounts of impurity metals. The Ti content affects the degree of crystal refinement (the degree of crystal grain size of the aluminum plate) and the electrochemical surface roughening. If the Ti content is less than 0.0010% by mass, the effect of crystal refining may not be observed.
The Ti content is 0.01 to 0.5% by mass. Preferably, it is 0.02-0.3 mass%, More preferably, it is 0.02-0.05 mass%.
[0024]
The Mg content affects the electrochemical surface roughening treatment. If the Mg content is less than 0.0001% by mass, an unetched part is likely to occur in nitric acid AC electrolysis.
The content of Mg is 0.1 to 1.5% by mass. Preferably, it is 0.30-1.5 mass%, More preferably, it is 0.50-1.35 mass%.
[0025]
The Mn content affects the electrochemical surface roughening treatment. If the Mn content is less than 0.0001% by mass, an unetched portion is likely to occur in hydrochloric acid alternating current electrolysis.
The Mn content is 0.1 to 1.5% by mass. Preferably, it is 0.30-1.40 mass%, More preferably, it is 0.50-1.30 mass%.
[0026]
When Cr and Zn are added in an amount of 0.00005% by mass or more, the effect of improving the resistance to severe ink stains is exhibited. It affects the subsequent surface structure. That is, they affect the microstructure in minimal etching. Cr is a foreign element contained in a small amount in JIS A5000 series, 6000 series, and 7000 series scraps.
Moreover, when there is too much these content, since an effect will be saturated and it will become disadvantageous in cost, it is unpreferable. In the present invention, the Cr content is 0.01 to 0.1% by mass, preferably 0.01 to 0.08% by mass, and more preferably the Cr content is 0.01 to 0.05% by mass. %.
Zn content is 0.1-1.5 mass%. Preferably, 0.1-1. It is 3 mass%, More preferably, it is 0.1-0.3 mass%.
[0027]
In order to use an aluminum alloy as a plate material, for example, the following method can be employed. First, a molten aluminum alloy adjusted to a predetermined alloy component content is subjected to a cleaning process and cast according to a conventional method. In the cleaning process, in order to remove unnecessary gas such as hydrogen in the molten metal, flux treatment, degassing process using argon gas, chlorine gas, etc., so-called rigid media filter such as ceramic tube filter, ceramic foam filter, A filtering process using a filter that uses alumina flakes, alumina balls or the like as a filter medium, a glass cloth filter, or a combination of a degassing process and a filtering process is performed.
[0028]
These cleaning treatments are preferably performed in order to prevent defects caused by foreign matters such as non-metallic inclusions and oxides in the molten metal and defects caused by gas dissolved in the molten metal. Regarding filtering of the molten metal, JP-A-6-57432, JP-A-3-162530, JP-A-5-140659, JP-A-4-231425, JP-A-4-276031, JP-A-5-311261, JP-A-5-311261 6-136466 and the like. Further, the degassing of the molten metal is described in JP-A-5-51659, Japanese Utility Model Laid-Open No. 5-49148, and the like. The applicant of the present application has also proposed a technique relating to degassing of molten metal in Japanese Patent Application Laid-Open No. 7-40017.
[0029]
Next, casting is performed using the molten metal that has been subjected to the cleaning treatment as described above. As for the casting method, there are a method using a solid mold typified by a DC casting method and a method using a driving mold typified by a continuous casting method.
In DC casting, solidification occurs at a cooling rate of 0.5 to 30 ° C./second. When the temperature is less than 1 ° C., many coarse intermetallic compounds may be formed. When DC casting is performed, an ingot having a thickness of 300 to 800 mm can be manufactured. The ingot is chamfered as necessary according to a conventional method, and usually 1 to 30 mm, preferably 1 to 10 mm, of the surface layer is cut. Before and after that, soaking treatment is performed as necessary. When performing a soaking treatment, heat treatment is performed at 450 to 620 ° C. for 1 to 48 hours so that the intermetallic compound does not become coarse. If the heat treatment is shorter than 1 hour, the effect of soaking may be insufficient. In addition, when soaking is not performed, there is an advantage that the cost can be reduced.
[0030]
Then, hot rolling and cold rolling are performed to obtain a rolled aluminum plate. An appropriate starting temperature for hot rolling is 350 to 500 ° C. An intermediate annealing treatment may be performed before or after hot rolling or in the middle thereof. The conditions for the intermediate annealing treatment are heating at 280 to 600 ° C. for 2 to 20 hours, preferably 350 to 500 ° C. for 2 to 10 hours using a batch annealing furnace, or 400 to 600 ° C. using a continuous annealing furnace. Heating is performed for 6 minutes or less, preferably 450 to 550 ° C. for 2 minutes or less. The crystal structure can be made finer by heating at a heating rate of 10 to 200 ° C./second using a continuous annealing furnace.
[0031]
The flatness of the aluminum plate finished to a predetermined thickness, for example, 0.1 to 0.5 mm by the above steps may be further improved by a correction device such as a roller leveler or a tension leveler. The flatness may be improved after the aluminum plate is cut into a sheet shape, but in order to improve the productivity, it is preferably performed in a continuous coil state. Further, a slitter line may be used for processing into a predetermined plate width. Moreover, in order to prevent generation | occurrence | production of the damage | wound by friction between aluminum plates, you may provide a thin oil film on the surface of an aluminum plate. As the oil film, a volatile or non-volatile film is appropriately used as necessary.
[0032]
On the other hand, as the continuous casting method, a twin roll method (hunter method), a method using a cooling roll typified by the 3C method, a double belt method (Hazley method), a cooling belt or a cooling block typified by Al-Swiss Caster II type The method using is industrially performed. When the continuous casting method is used, it solidifies at a cooling rate of 100 to 1000 ° C./second. Since the continuous casting method generally has a higher cooling rate than the DC casting method, it has a feature that the solid solubility of the alloy component in the aluminum matrix can be increased. Regarding the continuous casting method, the techniques proposed by the applicant of the present application are disclosed in JP-A-3-79798, JP-A-5-201166, JP-A-5-156414, JP-A-6-262203, and JP-A-6-122949. JP-A-6-210406 and JP-A-6-26308.
[0033]
When continuous casting is performed, for example, if a method using a cooling roll such as a Hunter method is used, a cast plate having a thickness of 1 to 10 mm can be directly cast continuously, and the hot rolling step is omitted. The advantage of being able to In addition, when a method using a cooling belt such as the Husley method is used, a cast plate having a thickness of 10 to 50 mm can be cast. Generally, a hot rolling roll is arranged immediately after casting and continuously rolled. Thus, a continuous cast and rolled plate having a thickness of 1 to 10 mm is obtained.
[0034]
These continuous cast and rolled plates are subjected to processes such as cold rolling, intermediate annealing, improvement of flatness, slits, and the like in the same manner as described for DC casting. Finished to a thickness of 5 mm. As for the intermediate annealing conditions and the cold rolling conditions when using the continuous casting method, the techniques proposed by the applicant of the present application are disclosed in JP-A-6-220593, JP-A-6-210308, JP-A-7-54111, It is described in JP-A-8-92709.
[0035]
The aluminum plate used in the present invention is preferably subjected to H18 tempering as defined in JIS.
[0036]
Various characteristics described below are desired for the aluminum plate thus manufactured.
As for the strength of the aluminum plate, it is preferable that the 0.2% proof stress is 120 MPa or more in order to obtain the stiffness required for a lithographic printing plate support. Moreover, in order to obtain a certain level of waist strength even when performing a burning treatment, the 0.2% yield strength after heat treatment at 270 ° C. for 3 to 10 minutes is preferably 80 MPa or more, and 100 MPa or more. It is more preferable that In particular, when the waist strength is required for an aluminum plate, an aluminum material added with Mg or Mn can be used, but if the waist is strengthened, the ease of fitting to the plate cylinder of a printing press becomes inferior. Depending on the application, the material and the amount of trace components added are appropriately selected. With regard to these, techniques proposed by the applicant of the present application are described in Japanese Patent Application Laid-Open Nos. 7-126820 and 62-140894.
The aluminum plate has a tensile strength of 160 ± 15 N / mm.²More preferably, the 0.2% proof stress is 140 ± 15 MPa, and the elongation specified in JIS Z2241 and Z2201 is 1 to 10%.
[0037]
The crystal structure of the aluminum plate may cause poor surface quality when the surface of the aluminum plate is subjected to chemical or electrochemical surface roughening. It is preferably not too coarse. The crystal structure on the surface of the aluminum plate preferably has a width of 200 μm or less, more preferably 100 μm or less, still more preferably 50 μm or less, and the length of the crystal structure is 5000 μm or less. Is preferably 1000 μm or less, and more preferably 500 μm or less. With regard to these, techniques proposed by the applicant of the present application are described in Japanese Patent Laid-Open Nos. 6-218495, 7-39906, and 7-124609.
[0038]
The alloy component distribution of the aluminum plate, when chemical surface roughening treatment or electrochemical surface roughening treatment is performed, poor surface quality occurs due to non-uniform distribution of the alloy component on the surface of the aluminum plate. Therefore, it is preferable that the surface is not very uneven. With regard to these, the techniques proposed by the applicant of the present application are described in Japanese Patent Laid-Open Nos. 6-48058, 5-301478, and 7-132689.
[0039]
In the present invention, unevenness is formed on the aluminum plate as shown above by press rolling, transfer or the like in the final rolling step or the like.
Above all, along with cold rolling to adjust the final plate thickness or finish cold rolling to finish the surface shape after final plate thickness adjustment, the uneven surface is transferred to the aluminum plate by pressing the uneven surface to the aluminum plate. A method of forming an uneven pattern is preferred. By making the aluminum surface uneven with the final cold rolling and simplifying the process, a large cost reduction can be achieved. As such a method, specifically, a method described in JP-A-6-262203 can be used.
[0040]
By using an aluminum plate having a concavo-convex pattern on the surface, it is possible to obtain a concavo-convex pattern having a uniform average pitch and depth than the concavo-convex pattern formed by the brush and the abrasive, thereby improving the stain resistance. Further, the amount of dampening water on the printing press can be easily adjusted (excellent in shinyness) while reducing energy consumed in the subsequent alkali etching treatment and roughening treatment. Further, in the first alkali etching process described later, the etching amount is 10 g / m.²This can be reduced to a degree or less, and the cost can be reduced. Further, when an aluminum plate having a concavo-convex pattern is used, the surface area of the obtained lithographic printing plate support is increased, so that the printing durability is more excellent.
[0041]
The transfer is particularly preferably performed in the final cold rolling step of a normal aluminum plate. Rolling for transfer is preferably performed in 1 to 3 passes, and the rolling reduction is preferably 3 to 8%.
Moreover, it is more preferable that the unevenness formed by the transfer is formed on both surfaces of the aluminum plate. Thereby, since the elongation rate of the aluminum plate of a surface and a back surface can be adjusted to the same grade, an aluminum plate with sufficient flatness can be obtained.
[0042]
As a method for obtaining a rolling roll having unevenness on its surface, which is used for unevenness transfer, for example, a method of subjecting the surface of a steel roll to a surface roughening treatment by shot blasting or sandblasting, and polishing with a grindstone or paper containing abrasive grains And a method of generating a dent by irradiating a laser, and a method of performing a chemical roughening treatment or an electrochemical roughening treatment. The roughening treatment by shot blasting or sand blasting may be wet or dry. When a chemical surface roughening treatment or an electrochemical surface roughening treatment is performed, a resist is applied, and then exposure and development are performed to generate a pattern, and etching can be performed so as to form the pattern.
After obtaining the rolling roll having irregularities on the surface by the above-described method, it is preferable to harden by quenching, hard chrome plating or the like in order to prevent surface abrasion.
[0043]
For example, JP-A-60-36195, JP-A-2002-251005, JP-A-60-203495, JP-A-55-74898, and JP-A-62-2 The method described in each publication of No. 111792 can be used.
[0044]
The irregularities formed on the surface of the rolling roll are adjusted so as to be oval concave portions that are transferred and formed on the surface of the aluminum plate. Specifically, for example, the surface roughness of the rolling roll is 0.5 to 3.0 μm, and R_zIs 5 to 10 μm, and it is preferable to form convex portions having an average diameter of 1 to 30 μm on the surface by hard chrome plating.
[0045]
It is preferable that an aluminum plate on which a concave and convex pattern having an oval concave portion is formed by the above-described press rolling, transfer or the like using a rolling roll having concave and convex surfaces has the following characteristics.
A structure having irregularities with a pitch of 1 to 100 μm on the surface is preferable.
Arithmetic average roughness (R_a) Is preferably 0.4 to 0.8 μm, and more preferably 0.45 to 0.65 μm. R_aIs 0.4 μm or more, in addition to the effect of using an aluminum plate having irregularities on the surface (described above), it is excellent in shiny when used as a lithographic printing plate, and R_aIs 0.8 μm or less, in addition to the effect of using an aluminum plate having irregularities on the surface (described above), the sensitivity when using a lithographic printing plate precursor is excellent. R_maxIs preferably 1 to 9 μm, and more preferably 3 to 7 μm. R_SmIs preferably 10 to 150 μm, more preferably 20 to 100 μm.
[0046]
In addition, the ellipse-shaped concave portions constituting the concave-convex pattern formed on the surface of the aluminum plate have an average length in the major axis direction (hereinafter sometimes simply referred to as “long diameter”) of 1 to 30 μm. Is more preferable, it is more preferable that it is 5-25 micrometers, and it is still more preferable that it is 10-20 micrometers.
[0047]
The average length ratio of the recesses {(average length in the long axis direction / length in the short axis direction) ratio, hereinafter, may be simply referred to as “average length ratio”. } Is preferably 1.6 to 4.0, more preferably 1.8 to 3.5, and still more preferably 2.0 to 3.0.
Furthermore, the number of concave portions on the surface is 200 to 40,000 pieces / mm.²Is preferred.
[0048]
Arithmetic mean roughness R of the surface of the aluminum plate_aIs measured with a stylus type roughness meter (for example, sufcom 575, manufactured by Tokyo Seimitsu Co., Ltd.), and the average roughness R defined in ISO 4287 is measured._aIs measured five times, and the average value is defined as the average roughness.
The conditions for the two-dimensional roughness measurement are shown below.
<Measurement conditions>
Cut-off value 0.8mm, tilt correction FLAT-ML, measurement length 3mm, vertical magnification 10000 times, scanning speed 0.3mm / sec, stylus tip diameter 2μm
R_maxAnd R_SmCan be measured according to ISO 4287.
[0049]
The average major axis and the average minor axis of the recesses formed on the surface of the aluminum plate are measured by, for example, photographing the surface of the aluminum plate from directly above at a magnification of 500 to 1000 times, preferably 700 to 800 times using an electron microscope. Then, in the obtained electron micrograph, at least 50 oval recesses whose periphery is continuous in an annular shape are extracted, the major axis and the minor axis are read, and the average value of each is calculated. The average length ratio is obtained by calculating the length ratio of each recess read above, and calculating the average value (that is, calculating (major axis / minor axis) of each recess, and calculating the average value of these ratios as the average length ratio. ).
Similarly, the number of concave portions on the surface can be obtained by photographing the surface of the aluminum plate from directly above using an electron microscope.
[0050]
The aluminum plate used in the present invention is a continuous belt-like sheet material or plate material. That is, it may be an aluminum web or a sheet-like sheet cut to a size corresponding to a planographic printing plate precursor shipped as a product.
Since scratches on the surface of the aluminum plate may become defects when processed into a lithographic printing plate support, it is possible to generate scratches at the stage prior to the surface treatment process for making a lithographic printing plate support It is necessary to suppress as much as possible. For that purpose, it is preferable that the package has a stable form and is not easily damaged during transportation.
In the case of an aluminum web, for example, the packing form of aluminum is, for example, laying a hardboard and felt on an iron pallet, applying cardboard donut plates to both ends of the product, wrapping the whole with a polytube, and inserting a wooden donut into the inner diameter of the coil Then, a felt is applied to the outer periphery of the coil, the band is squeezed with a band, and the display is performed on the outer periphery. Moreover, a polyethylene film can be used as the packaging material, and a needle felt or a hard board can be used as the cushioning material. There are various other forms, but the present invention is not limited to this method as long as it is stable and can be transported without being damaged.
[0051]
The thickness of the aluminum plate used in the present invention is about 0.1 mm to 0.6 mm, preferably 0.15 mm to 0.4 mm, and more preferably 0.2 mm to 0.3 mm. This thickness can be appropriately changed according to the size of the printing press, the size of the printing plate, the user's desires, and the like.
[0052]
<Mechanical roughening>
In the production method of the present invention, the aluminum plate having a concavo-convex pattern on the surface described above may be performed without performing a mechanical surface roughening treatment using a rotating brush and an abrasive described below.
When a mechanical surface roughening process using a brush and an abrasive is performed, the surface area can be increased by the subsequent brush grain process even when the surface area is small due to the concavo-convex pattern formed by transfer, and appropriate water retention is achieved. it can. On the other hand, when the conventional method is performed only with a brush and a polishing agent, it is possible to solve the problem that sharp irregularities are formed, the remaining film tends to remain, and dirt easily remains at the edge. Further, the amount of subsequent alkali etching can be reduced, which is advantageous in terms of cost.
[0053]
Hereinafter, the brush grain method used suitably as a mechanical roughening process is demonstrated.
The brush grain method generally uses a roller-shaped brush in which a large number of brush hairs such as synthetic resin hair made of synthetic resin such as nylon (trade name), propylene, and vinyl chloride resin are implanted on the surface of a cylindrical body. This is carried out by rubbing one or both of the surfaces of the aluminum plate while spraying a slurry liquid containing an abrasive on a rotating roller brush. Instead of the roller brush and the slurry liquid, a polishing roller which is a roller having a polishing layer on the surface can be used.
[0054]
When using a roller brush, the flexural modulus is preferably 10,000 to 40,000 kg / cm.², More preferably 15,000-35,000 kg / cm²In addition, brush hair having a bristle waist strength of preferably 500 g or less, more preferably 400 g or less is used. The diameter of the brush bristles is generally 0.2 to 0.9 mm. The length of the brush bristles can be appropriately determined according to the outer diameter of the roller brush and the diameter of the body, but is generally 10 to 100 mm.
In the present invention, it is preferable to use a plurality of nylon brushes, specifically, 3 or more are more preferable, and 4 or more are particularly preferable. By adjusting the number of brushes, the wavelength component of the recess formed on the aluminum plate surface can be adjusted.
[0055]
The load of the drive motor that rotates the brush is preferably 1 kW plus or more, more preferably 2 kW plus or more, and particularly preferably 8 kW plus or more with respect to the load before the brush roller is pressed against the aluminum plate. By adjusting the load, the depth of the recess formed on the surface of the aluminum plate can be adjusted. The number of rotations of the brush is preferably 100 or more, and particularly preferably 200 or more.
[0056]
A well-known thing can be used for an abrasive | polishing agent. For example, abrasives such as pumice stone (pumice stone), silica sand, aluminum hydroxide, alumina powder, silicon carbide, silicon nitride, volcanic ash, carborundum, and gold sand; a mixture thereof can be used. Of these, pumiston and silica sand are preferable. Quartz sand is harder and less fragile than Pamiston, so it has excellent roughening efficiency. In addition, aluminum hydroxide is suitable when an excessive load is applied and the particles are damaged, so that it is not desired to generate deep recesses locally.
The median diameter of the abrasive is preferably from 2 to 100 μm, more preferably from 20 to 60 μm, from the viewpoint of excellent surface roughening efficiency and the ability to narrow the graining pitch. By adjusting the median diameter of the abrasive, the depth of the recess formed on the surface of the aluminum plate can be adjusted.
[0057]
For example, the abrasive is suspended in water and used as a slurry. In addition to the abrasive, the slurry liquid may contain a thickener, a dispersant (for example, a surfactant), a preservative, and the like. The specific gravity of the slurry liquid is preferably 0.5-2.
As an apparatus suitable for the mechanical surface roughening treatment, for example, an apparatus described in Japanese Patent Publication No. 50-40047 can be given.
[0058]
As for details of an apparatus for performing a mechanical surface roughening process using a brush and an abrasive, those described in JP-A-2002-2111159 can be used by the applicant of the present application.
[0059]
In the present invention, when an aluminum plate having a concavo-convex pattern formed on the surface by transfer is further mechanically roughened using a rotating brush and an abrasive, the amount of increase in Ra is 0.3 or less. It is preferable that it is 0.2 or less and 0.1 or less.
[0060]
<Surface treatment>
In the method for producing a lithographic printing plate support of the present invention, a roughening treatment and an anodic oxidation treatment (in the present invention, both are referred to as a surface treatment) are performed on the above-described aluminum plate having a concavo-convex pattern formed thereon. To obtain a lithographic printing plate support.
In the roughening treatment, electrochemical roughening treatment is preferably performed twice, and an etching treatment in an alkaline aqueous solution is preferably performed between them. Etching treatment in an alkaline aqueous solution (first), in an acidic aqueous solution Desmutting treatment (first), electrochemical surface roughening treatment in aqueous solution containing nitric acid or hydrochloric acid (first electrolytic treatment), etching treatment in alkaline aqueous solution (second), in acidic aqueous solution Desmutting treatment (second), electrochemical surface roughening treatment in aqueous solution containing hydrochloric acid (second electrolytic treatment), etching treatment in alkaline aqueous solution (third) and desmutting treatment in acidic aqueous solution (first 3) It is more preferable to perform the anodizing treatment in this order.
In the method for producing a lithographic printing plate support of the present invention, various steps other than those described above may be included.
[0061]
It is also preferable to perform a hydrophilic treatment after the anodizing treatment.
Hereinafter, each step of the surface treatment will be described in detail.
[0062]
<First alkali etching treatment>
The alkali etching treatment is a treatment for dissolving the surface layer by bringing the above-described aluminum plate into contact with an alkali solution.
[0063]
The first alkaline etching treatment performed before the first electrolytic treatment is to form a uniform recess in the first electrolytic treatment, and to remove rolling oil, dirt, natural oxide film, etc. on the surface of the aluminum plate (rolled aluminum). This is done for the purpose of removal.
In the first alkaline etching treatment, the etching amount is 0.1 g / m.²Preferably, it is 0.5 g / m²More preferably, it is 1 g / m.²More preferably, it is 10 g / m.²The following is preferable, 8 g / m²More preferably, it is 5 g / m or less.²More preferably, it is as follows. When the lower limit of the etching amount is within the above range, uniform pits can be generated in the first electrolytic treatment, and further, processing unevenness can be prevented. When the upper limit of the etching amount is in the above range, the amount of the alkaline aqueous solution used is reduced, which is economically advantageous.
[0064]
Examples of the alkali used in the alkaline solution include caustic alkali and alkali metal salts. Specifically, examples of caustic alkali include caustic soda and caustic potash. Examples of the alkali metal salt include alkali metal silicates such as sodium metasilicate, sodium silicate, potassium metasilicate, and potassium silicate; alkali metal carbonates such as sodium carbonate and potassium carbonate; sodium aluminate and alumina. Alkali metal aluminates such as potassium acid; alkali metal aldones such as sodium gluconate and potassium gluconate; dibasic sodium phosphate, dibasic potassium phosphate, primary sodium phosphate, primary potassium phosphate, etc. An alkali metal hydrogen phosphate is mentioned. Among these, a caustic alkali solution and a solution containing both a caustic alkali and an alkali metal aluminate are preferable from the viewpoint of high etching rate and low cost. In particular, an aqueous solution of caustic soda is preferable.
[0065]
In the first alkali etching treatment, the concentration of the alkaline solution is preferably 30 g / L or more, more preferably 300 g / L or more, and preferably 500 g / L or less, 450 g / L. The following is more preferable.
The alkaline solution preferably contains aluminum ions. The aluminum ion concentration is preferably 1 g / L or more, more preferably 50 g / L or more, and preferably 200 g / L or less, more preferably 150 g / L or less. Such an alkaline solution can be prepared using, for example, water, a 48 mass% sodium hydroxide aqueous solution, and sodium aluminate.
[0066]
In the first alkali etching treatment, the temperature of the alkaline solution is preferably 30 ° C. or higher, more preferably 50 ° C. or higher, and preferably 80 ° C. or lower, and 75 ° C. or lower. Is more preferable.
In the first alkali etching treatment, the treatment time is preferably 1 second or longer, more preferably 2 seconds or longer, more preferably 30 seconds or shorter, and more preferably 15 seconds or shorter. preferable.
[0067]
When the aluminum plate is continuously etched, the aluminum ion concentration in the alkaline solution increases, and the etching amount of the aluminum plate varies. Therefore, the composition management of the etching solution is preferably performed as follows.
That is, a matrix of conductivity, specific gravity, and temperature, or a matrix of conductivity, ultrasonic velocity, and temperature, corresponding to the matrix of caustic soda concentration and aluminum ion concentration, is prepared in advance, and the conductivity and specific gravity. The liquid composition is measured according to the temperature and temperature, or the electrical conductivity, the ultrasonic wave propagation speed, and the temperature, and caustic soda and water are added so that the control target value of the liquid composition is reached. Then, the amount of the etching liquid increased by adding caustic soda and water is overflowed from the circulation tank, thereby keeping the liquid amount constant. As caustic soda to be added, 40 to 60% by mass for industrial use can be used.
As the conductivity meter and the specific gravity meter, it is preferable to use those that are temperature-compensated. As the specific gravity meter, a differential pressure type is preferably used.
[0068]
Examples of the method of bringing the aluminum plate into contact with the alkaline solution include, for example, a method in which the aluminum plate is passed through a tank containing the alkaline solution, a method in which the aluminum plate is immersed in a tank containing the alkaline solution, The method of spraying on the surface of a board is mentioned.
[0069]
Among these, a method in which an alkali solution is sprayed on the surface of an aluminum plate is preferable. Specifically, a method of spraying an etching solution in an amount of 10 to 100 L / min per spray tube from a spray tube having φ2 to 5 mm holes at a pitch of 10 to 50 mm is preferable. It is preferable to provide a plurality of spray tubes.
[0070]
After the alkali etching process is completed, it is preferable to drain the liquid with a nip roller, and further perform the water washing process for 1 to 10 seconds and then drain the liquid with a nip roller.
The water washing treatment is preferably carried out using an apparatus for washing with a free-falling curtain-like liquid film, and further using a spray tube.
[0071]
FIG. 1 is a schematic cross-sectional view of an apparatus for washing with a free-falling curtain-like liquid film. As shown in FIG. 1, an apparatus 100 for performing water washing treatment with a free-fall curtain-like liquid film includes a water storage tank 104 that stores water 102, a water supply pipe 106 that supplies water to the water storage tank 104, and a water storage tank. And a rectifying unit 108 for supplying a free fall curtain-like liquid film from 104 to the aluminum plate 1.
In the apparatus 100, water 102 is supplied to the water supply tank 104 from the water supply pipe 106, and when the water 102 overflows from the water supply tank 104, the water is rectified by the rectifying unit 108, and a free-falling curtain-like liquid film is applied to the aluminum plate 1. Supplied. When the apparatus 100 is used, the liquid amount is preferably 10 to 100 L / min. Moreover, it is preferable that the distance L where the water 102 between the apparatus 100 and the aluminum 1 exists as a free fall curtain-like liquid film is 20-50 mm. Moreover, it is preferable that the angle (alpha) of an aluminum plate is 30-80 degrees with respect to a horizontal direction.
[0072]
If an apparatus for washing with a free-fall curtain-like liquid film as shown in FIG. 1 is used, the aluminum plate can be uniformly washed with water, so that the uniformity of the treatment performed before the washing process is improved. Can be improved.
As a specific apparatus for washing with a free-fall curtain-like liquid film, for example, an apparatus described in JP-A-2003-96584 is preferably exemplified.
[0073]
Moreover, as a spray tube used for the water-washing process, for example, a spray tube having a plurality of spray tips in the width direction of the aluminum plate in which spray water spreads in a fan shape can be used. The distance between spray tips is preferably 20 to 100 mm, and the amount of liquid per spray tip is preferably 0.5 to 20 L / min. It is preferable to use a plurality of spray tubes.
[0074]
<First desmut treatment>
After the first alkali etching treatment, pickling (first desmutting treatment) is preferably performed in order to remove dirt (smut) remaining on the surface. The desmut treatment is performed by bringing an aluminum plate into contact with an acidic solution.
[0075]
Examples of the acid used include nitric acid, sulfuric acid, phosphoric acid, chromic acid, hydrofluoric acid, and borohydrofluoric acid.
In the first desmut process performed after the first alkali etching process, when nitric acid electrolysis is subsequently performed as the first electrolysis process, it is preferable to use an overflow waste liquid of the electrolyte used for nitric acid electrolysis.
[0076]
In the composition management of the desmut treatment liquid, a method of managing by conductivity and temperature, a method of managing by conductivity, specific gravity and temperature, and a conductivity and superconductivity corresponding to a matrix of acidic solution concentration and aluminum ion concentration. Either of the methods managed by the propagation speed of sound waves and temperature can be selected and used.
[0077]
In the first desmutting treatment, it is preferable to use an acidic solution containing 1 to 400 g / L of acid and 0.1 to 5 g / L of aluminum ions.
[0078]
The temperature of the acidic solution is preferably 20 ° C. or more, more preferably 30 ° C. or more, and preferably 70 ° C. or less, more preferably 60 ° C. or less.
[0079]
In the first desmutting treatment, the treatment time is preferably 1 second or longer, more preferably 4 seconds or longer, and preferably 60 seconds or shorter, more preferably 40 seconds or shorter. .
[0080]
Examples of the method of bringing the aluminum plate into contact with the acidic solution include, for example, a method of passing the aluminum plate through a bath containing the acidic solution, a method of immersing the aluminum plate in a bath containing the acidic solution, and an acidic solution containing aluminum. The method of spraying on the surface of a board is mentioned.
Among these, a method in which an acidic solution is sprayed on the surface of an aluminum plate is preferable. Specifically, a method of spraying an etching solution in an amount of 10 to 100 L / min per spray tube from a spray tube having φ2 to 5 mm holes at a pitch of 10 to 50 mm is preferable. It is preferable to provide a plurality of spray tubes.
[0081]
After the desmutting process is completed, it is preferable to drain the liquid with a nip roller, and further perform the water washing process for 1 to 10 seconds, and then drain the liquid with a nip roller.
The water washing treatment is the same as the water washing treatment after the alkali etching treatment. However, the amount of liquid per spray tip is preferably 1 to 20 L / min.
In addition, in the first desmutting treatment, when using the overflow waste solution of the electrolyte solution used for the subsequent nitric acid electrolysis as the desmutting treatment solution, the surface of the aluminum plate is not subjected to the draining with a nip roller and the water washing treatment after the desmutting treatment. It is preferable to handle the aluminum plate up to the nitric acid electrolysis step while spraying a desmut treatment solution as necessary so that it does not dry.
[0082]
<First electrolytic treatment>
The first electrolytic treatment is an electrochemical surface roughening treatment in an aqueous solution containing nitric acid or hydrochloric acid.
In the present invention, by performing the first electrolytic treatment and the second electrolytic treatment in this order, it is possible to form a grained shape with a highly uniform concavo-convex structure on the surface of the aluminum plate. The printing durability can be improved.
In addition, it is preferable that the average roughness of the aluminum plate surface after a 1st electrolytic process is 0.45-0.85 micrometer.
[0083]
(Electrochemical roughening treatment in aqueous solution containing nitric acid: 1st nitric acid electrolysis)
A suitable uneven structure can be formed on the surface of the aluminum plate by electrochemical surface roughening treatment (nitric acid electrolysis) in an aqueous solution containing nitric acid. In the present invention, when the aluminum plate contains a relatively large amount of Cu, a relatively large and uniform recess is formed in nitric acid electrolysis. As a result, the lithographic printing plate using the lithographic printing plate support obtained by the present invention has excellent printing durability.
[0084]
The aqueous solution containing nitric acid can be one used for electrochemical surface roughening using ordinary direct current or alternating current, and an aqueous solution of nitric acid having a concentration of 1 to 100 g / L can be used for aluminum nitrate, sodium nitrate, ammonium nitrate, etc. At least one of the nitrate compounds having the nitrate ion can be added and used in the range from 1 g / L to saturation. Moreover, the metal contained in aluminum alloys, such as iron, copper, manganese, nickel, titanium, magnesium, a silica, may melt | dissolve in the aqueous solution containing nitric acid. Hypochlorous acid or hydrogen peroxide may be added at 1 to 100 g / L.
Specifically, a solution prepared by dissolving aluminum nitrate in an aqueous nitric acid solution having a nitric acid concentration of 5 to 15 g / L and adjusting the aluminum ion concentration to 3 to 7 g / L is preferable.
[0085]
Further, by adding and using a compound capable of forming a complex with Cu, uniform graining is possible even for an aluminum plate containing a large amount of Cu. Examples of the compound capable of forming a complex with Cu include ammonia; hydrogen atom of ammonia such as methylamine, ethylamine, dimethylamine, diethylamine, trimethylamine, cyclohexylamine, triethanolamine, triisopropanolamine, EDTA (ethylenediaminetetraacetic acid). And amines obtained by substituting with a hydrocarbon group (aliphatic, aromatic, etc.); metal carbonates such as sodium carbonate, potassium carbonate, potassium hydrogen carbonate and the like. In addition, ammonium salts such as ammonium nitrate, ammonium chloride, ammonium sulfate, ammonium phosphate, and ammonium carbonate are also included.
[0086]
The temperature of the aqueous solution containing nitric acid is preferably 30 ° C or higher, and preferably 55 ° C or lower.
[0087]
Pits having an average opening diameter of 1 to 10 μm can be formed by nitric acid electrolysis. However, when the amount of electricity is relatively large, the electrolytic reaction is concentrated, and honeycomb pits exceeding 10 μm are also generated.
In order to obtain such a grain, the total amount of electricity involved in the anode reaction of the aluminum plate at the time when the electrolytic reaction is completed is 150 C / dm.²Or more, preferably 170 C / dm²More preferably, it is 600 C / dm.²Or less, preferably 500 C / dm²The following is more preferable. The current density at this time is 20 to 100 A / dm at the peak current value when alternating current is used.²It is preferable that 20-100 A / dm when direct current is used.²Is preferred.
[0088]
When the following pre-electrolysis is performed before nitric acid electrolysis, a more uniform recess is formed in nitric acid electrolysis.
Pre-electrolysis is a process of forming the starting point of pit formation during nitric acid electrolysis. By performing slight electrolysis using hydrochloric acid which is not easily affected by the material of the aluminum plate and is highly corrosive, pits can be formed uniformly on the surface.
In pre-electrolysis, the hydrochloric acid concentration is preferably 1 to 15 g / L, and the amount of electricity at the time of anode is 30 to 70 C / m.²Is preferred.
After pre-electrolysis, it is preferable to perform alkali etching to remove smut. The amount of aluminum dissolved in alkali etching is 0.2 to 0.6 g / m.²Is preferred.
[0089]
(Electrochemical roughening treatment in aqueous solution containing hydrochloric acid: 1st hydrochloric acid electrolysis)
As the aqueous solution containing hydrochloric acid, those used for the electrochemical surface roughening treatment using ordinary direct current or alternating current can be used, and 1-30 g / L, preferably 2-10 g / L aqueous hydrochloric acid solution is added to aluminum nitrate. One or more of hydrochloric acid or nitric acid compounds having nitrate ions such as sodium nitrate and ammonium nitrate and hydrochloric acid ions such as aluminum chloride, sodium chloride and ammonium chloride can be added to 1 g / L to saturation. Moreover, the compound which forms above-mentioned copper and a complex can also be added in the ratio of 1-200 g / L. In the aqueous solution containing hydrochloric acid, a metal contained in an aluminum alloy such as iron, copper, manganese, nickel, titanium, magnesium, or silica may be dissolved. Hypochlorous acid or hydrogen peroxide may be added at 1 to 100 g / L.
[0090]
The aqueous hydrochloric acid solution is preferably an aqueous solution containing 2 to 10 g / L of hydrochloric acid, and an aluminum salt (aluminum chloride, AlCl₃・ 6H₂Particularly preferred is an aqueous solution in which O) is added at a rate of 27 to 63 g / L so that the aluminum ion concentration is 3 to 7 g / L, preferably 4 to 6 / L. When an electrochemical surface roughening treatment is performed using such an aqueous hydrochloric acid solution, the surface shape by the surface roughening treatment becomes uniform, and a low purity aluminum rolled plate or a high purity aluminum rolled plate can be used. Further, the processing unevenness due to the roughening treatment does not occur, and it is possible to achieve both excellent printing durability and stain resistance when using a lithographic printing plate.
[0091]
The temperature of the aqueous solution containing hydrochloric acid is preferably 25 ° C. or higher, more preferably 30 ° C. or higher, more preferably 55 ° C. or lower, and even more preferably 40 ° C. or lower.
[0092]
As the additive, apparatus, power source, current density, flow rate, and temperature in the aqueous solution containing hydrochloric acid, those used for known electrochemical surface roughening can be used. AC or DC is used as the power source used for electrochemical roughening, but AC is particularly preferable.
[0093]
Since hydrochloric acid itself has a strong ability to dissolve aluminum, it is possible to form fine irregularities on the surface with only slight electrolysis. These fine irregularities have an average opening diameter of 0.01 to 0.4 μm and are uniformly generated on the entire surface of the aluminum plate.
Further, when the amount of electricity is increased, pits having an average opening diameter of 1 to 15 μm having pits having an average opening diameter of 0.01 to 0.4 μm on the surface are generated. In order to obtain such a grain, the total amount of electricity involved in the anode reaction of the aluminum plate at the end of the electrolytic reaction is 10 C / dm.²Or more, preferably 50 C / dm²More preferably, it is more preferably 100 C / dm.²The above is preferable. 2000C / dm²Or less, preferably 600 C / dm²The following is more preferable.
[0094]
In the first hydrochloric acid electrolysis, the total amount of electricity involved in the anode reaction is 150 to 2000 C / dm.²It is also possible to form a large crater-like undulation at the same time. Even in this case, pits with an average opening diameter of 1 to 15 μm having fine irregularities with an average opening diameter of 0.01 to 0.4 μm on the surface are generated. The current density at this time is 20 to 100 A / dm at the peak value of the current.²Is preferred.
[0095]
When hydrochloric acid is electrolyzed on an aluminum plate with a large amount of electricity as described above, large waviness and fine irregularities can be formed at the same time, and the large waviness is made more uniform by the second alkali etching process described later, thereby improving stain resistance. Can be made.
[0096]
The first electrolytic treatment using an aqueous solution containing nitric acid or hydrochloric acid follows, for example, the electrochemical grain method (electrolytic grain method) described in Japanese Patent Publication No. 48-28123 and British Patent No. 896,563. be able to. This electrolytic grain method uses a sinusoidal alternating current, but it may be performed using a special waveform as described in JP-A-52-58602. Further, the waveform described in JP-A-3-79799 can also be used. JP-A-55-158298, JP-A-56-28898, JP-A-52-58602, JP-A-52-152302, JP-A-54-85802, JP-A-60-190392, JP-A-58-120531, JP-A-63-176187, JP-A-1-5889, JP-A-1-280590, JP-A-1-118489, JP-A-1-148592, and JP-A-1-17896. JP-A-1-188315, JP-A-1-1549797, JP-A-2-235794, JP-A-3-260100, JP-A-3-253600, JP-A-4-72079, JP-A-4-72098, The methods described in JP-A-3-267400 and JP-A-1-141094 can also be applied. In addition to the above, it is also possible to perform electrolysis using an alternating current having a special frequency that has been proposed as a method of manufacturing an electrolytic capacitor. For example, it is described in US Pat. Nos. 4,276,129 and 4,676,879.
[0097]
Various electrolyzers and power sources have been proposed, including US Pat. No. 4,203,637, JP-A-56-123400, JP-A-57-59770, JP-A-53-12738, JP 53-32821, JP 53-32222, JP 53-32823, JP 55-122896, JP 55-13284, JP 62-127500, JP Those described in JP-A-1-52100, JP-A-1-52098, JP-A-60-67700, JP-A-1-230800, JP-A-3-257199 and the like can be used.
Also, JP-A-52-58602, JP-A-52-152302, JP-A-53-12738, JP-A-53-12739, JP-A-53-32821, JP-A-53-32822, JP 53-32833, JP 53-32824, JP 53-32825, JP 54-85802, JP 55-122896, JP 55-13284, JP 48-28123, JP-B-51-7081, JP-A-52-133638, JP-A-52-133840, JP-A-52-133844, JP-A-52-133845, JP-A-53-149135 And those described in JP-A No. 54-146234 and the like can also be used.
[0098]
When the aluminum plate is continuously subjected to electrolytic surface roughening, the aluminum ion concentration in the alkaline solution increases, and the uneven shape of the aluminum plate formed by the first electrolytic treatment varies. Therefore, the composition management of the nitric acid electrolytic solution or hydrochloric acid electrolytic solution is preferably performed as follows.
That is, a matrix of conductivity, specific gravity, and temperature, or a matrix of conductivity, ultrasonic propagation velocity, and temperature corresponding to a matrix of nitric acid concentration or hydrochloric acid concentration and aluminum ion concentration is prepared in advance. The liquid composition is measured by the degree, specific gravity and temperature, or the electric conductivity, the ultrasonic wave propagation speed and the temperature, and nitric acid or hydrochloric acid and water are added so as to reach the control target value of the liquid composition. Then, the electrolytic solution increased by adding nitric acid or hydrochloric acid and water is overflowed from the circulation tank, so that the amount of the electrolytic solution is kept constant. As nitric acid to be added, 30 to 70% by mass of industrial grade can be used. As hydrochloric acid to add, the industrial thing of 30-40 mass% can be used.
As the conductivity meter and the specific gravity meter, it is preferable to use those that are temperature-compensated. As the specific gravity meter, a differential pressure type is preferably used.
Samples taken from the electrolyte for use in measuring the liquid composition are used for measurement after being controlled at a constant temperature (eg, 40 ± 0.5 ° C.) using a heat exchanger different from the electrolyte. However, it is preferable in that the accuracy of measurement is increased.
[0099]
The AC power supply wave used for the electrochemical surface roughening treatment is not particularly limited, and a sine wave (sine wave), a rectangular wave, a trapezoidal wave, a triangular wave, and the like are used, and a sine wave, a rectangular wave, or a trapezoidal wave is preferable. A trapezoidal wave is particularly preferred. In the case of the first hydrochloric acid electrolysis, a sine wave is particularly preferable in that pits having an average diameter of 1 μm or more are easily generated. The sine wave is the one shown in FIG.
A trapezoidal wave means what was shown in FIG. In this trapezoidal wave, the time (TP) until the current reaches a peak from zero is preferably 0.5 to 3 msec. When TP exceeds 3 msec, especially when an aqueous solution containing nitric acid is used, it becomes susceptible to the influence of trace components in the electrolytic solution typified by ammonium ions and the like that spontaneously increase by electrolytic treatment, and uniform graining. Is difficult to be performed. As a result, the stain resistance tends to decrease when a lithographic printing plate is obtained.
[0100]
An AC duty ratio of 1: 2 to 2: 1 can be used. However, as described in Japanese Patent Laid-Open No. 5-195300, in an indirect power feeding method in which no conductor roll is used for aluminum, a duty ratio is used. Is preferably 1: 1.
An AC frequency of 0.1 to 120 Hz can be used, but 50 to 70 Hz is preferable in terms of equipment. When the frequency is lower than 50 Hz, the carbon electrode of the main electrode is easily dissolved, and when the frequency is higher than 70 Hz, it is easily affected by an inductance component on the power supply circuit, and the power supply cost is increased.
[0101]
FIG. 3 is a side view showing an example of a radial type cell used for electrochemical roughening treatment using alternating current in the method for producing a lithographic printing plate support of the present invention.
One or more AC power supplies can be connected to the electrolytic cell. As shown in FIG. 3, the current ratio between the AC anode and cathode applied to the aluminum plate facing the main electrode is controlled to achieve uniform graining and to dissolve the carbon of the main electrode. In addition, it is preferable to install an auxiliary anode and divert part of the alternating current. In FIG. 3, 11 is an aluminum plate, 12 is a radial drum roller, 13a and 13b are main poles, 14 is an electrolytic treatment liquid, 15 is an electrolytic solution supply port, and 16 is a slit. , 17 is an electrolyte passage, 18 is an auxiliary anode, 19a and 19b are thyristors, 20 is an AC power source, 40 is a main electrolytic cell, and 50 is an auxiliary anode cell. An anodic reaction that acts on the aluminum plate facing the main electrode by diverting a part of the current value as a direct current to an auxiliary anode provided in a tank separate from the two main electrodes via a rectifier or switching element It is possible to control the ratio between the current value for the current and the current value for the cathode reaction. On the aluminum plate facing the main electrode, the ratio of the amount of electricity involved in the anodic reaction and the cathodic reaction (the amount of electricity at the time of cathode / the amount of electricity at the time of anode) is preferably 0.3 to 0.95.
[0102]
As the electrolytic cell, electrolytic cells used for known surface treatments such as a vertical type, a flat type, and a radial type can be used, but a radial type electrolytic cell as described in JP-A-5-195300 is particularly preferable. . The electrolytic solution passing through the electrolytic cell may be parallel to the traveling direction of the aluminum web or may be a counter.
[0103]
In addition, in the electrochemical surface roughening treatment using direct current, an electrolytic solution used for the normal electrochemical surface roughening treatment using direct current can be used. Specifically, the same electrolyte solution used for the electrochemical surface roughening treatment using the alternating current can be used.
[0104]
The DC power source wave used for the electrochemical surface roughening treatment is not particularly limited as long as the current does not change in polarity, and a comb wave, continuous DC, commercial AC that is full-wave rectified with a thyristor, etc. can be used. Smoothed continuous direct current is preferred.
The electrochemical surface roughening treatment using direct current can be performed by any of a batch method, a semi-continuous method, and a continuous method, but is preferably performed by a continuous method.
[0105]
The apparatus used for the electrochemical surface roughening treatment using direct current applies a direct current voltage between alternately arranged anodes and cathodes, and passes through the aluminum plate at a distance from the anodes and the cathodes. If it can be made, it will not be specifically limited.
For example, the apparatus which has one electrolytic cell shown by FIG. 6 is mentioned. In FIG. 6, the aluminum plate 61 passes through an electrolytic tank 65 filled with an electrolytic solution 64. A DC voltage is applied between the anodes 62 and the cathodes 63 arranged alternately in the electrolytic cell 65. In the electrolytic bath 65, the electrolytic solution 64 is supplied from the liquid supply nozzle 66 and discharged through the drainage pipe 67.
Moreover, the apparatus whose tank of the anode 62 shown in FIG. 7 and the tank of the cathode 63 are separate electrolytic cells is also mentioned. In FIG. 7, the aluminum plate 61 passes through a plurality of electrolytic cells 65 filled with the electrolytic solution 64. In each electrolytic cell 65, anodes 62 or cathodes 63 are alternately arranged. A DC voltage is applied between the anodes 62 and the cathodes 63 arranged alternately. In each electrolytic tank 65, the electrolytic solution 64 is supplied from the liquid supply pipe 68 and is discharged through the drainage pipe 67.
[0106]
An electrode is not specifically limited, The conventionally well-known electrode used for an electrochemical roughening process can be used.
As the anode, for example, a valve metal such as titanium, tantalum, or niobium is plated or clad with a platinum group metal; the valve metal is coated with an oxide of a platinum group metal or sintered. Aluminium; stainless steel. Among these, a valve metal obtained by cladding platinum is preferable. The life of the anode can be further extended by a method such as water-cooling by passing water through the electrode.
As the cathode, for example, a metal that does not dissolve when the electrode potential is negative can be selected and used from the Boolean Bay diagram. Among these, carbon is preferable.
[0107]
The arrangement of the electrodes can be appropriately selected according to the wave structure. Also, by changing the length of the aluminum plate between the anode and the cathode in the traveling direction, changing the passage speed of the aluminum plate, returning the flow rate of the electrolyte, liquid temperature, liquid composition, current density, etc. Can be adjusted. In addition, as in the apparatus shown in FIG. 7, when the anode tank and the cathode tank are separate electrolytic cells, the electrolysis conditions of each treatment tank can be changed.
[0108]
In the measurement of the average opening diameter of the recesses generated by the first electrolytic treatment, for example, the surface of the support was photographed at a magnification of 2000 times or 50000 times from directly above using an electron microscope. Extracting at least 50 pits each having a ring shape around the pits generated in the above, reading the diameters as the opening diameters, and calculating the average opening diameter.
In addition, in order to suppress variation in measurement, it is possible to perform equivalent circle diameter measurement using commercially available image analysis software. In this case, the electron micrograph is captured by a scanner, digitized, and binarized by software, and then an equivalent circle diameter is obtained.
As a result of measurement by the present inventor, the result of visual measurement and the result of digital processing showed almost the same value.
[0109]
After the first electrolytic treatment is completed, it is preferable to drain the liquid with a nip roller, and further perform the water washing treatment for 1 to 10 seconds, and then drain the liquid with a nip roller.
The washing treatment is preferably carried out using a spray tube. As the spray tube used for the water washing treatment, for example, a spray tube having a plurality of spray tips in the width direction of the aluminum plate in which fan water spreads in a fan shape can be used. The distance between spray tips is preferably 20 to 100 mm, and the amount of liquid per spray tip is preferably 1 to 20 L / min. It is preferable to use a plurality of spray tubes.
[0110]
<Second alkali etching treatment>
The second alkaline etching process performed between the first electrolytic process and the second electrolytic process involves dissolving the smut generated by the first electrolytic process and removing the edge portion of the pit formed by the first electrolytic process. It is performed for the purpose of dissolving. As a result, the edge portion of the large pit formed by the first electrolytic treatment solution is melted and the surface becomes smooth, and it is difficult to catch the ink on the edge portion, so that a lithographic printing plate precursor having excellent stain resistance is obtained. Can do.
Since the second alkali etching process is basically the same as the first alkali etching process, only different points will be described below.
[0111]
In the second alkali etching treatment, the etching amount is 0.05 g / m.²Preferably, it is 0.1 g / m²More preferably, it is 4 g / m.²The following is preferable, 3.5 g / m²The following is more preferable. Etching amount is 0.05g / m²When it is as described above, in the non-image portion of the lithographic printing plate, the edge portion of the pit generated by the first electrolytic treatment becomes smooth and the ink is not easily caught, so that the stain resistance is excellent. On the other hand, the etching amount is 4 g / m.²Since the unevenness | corrugation produced | generated by the 1st electrolytic process becomes large as it is the following, printing durability is excellent.
[0112]
In the second alkali etching treatment, the concentration of the alkaline solution is preferably 30 g / L or more, more preferably 300 g / L or more, and preferably 500 g / L or less, 450 g / L. The following is more preferable.
The alkaline solution preferably contains aluminum ions. The aluminum ion concentration is preferably 1 g / L or more, more preferably 50 g / L or more, and preferably 200 g / L or less, more preferably 150 g / L or less. Such an alkaline solution can be prepared using, for example, water, a 48 mass% sodium hydroxide aqueous solution, and sodium aluminate.
[0113]
<Second desmut treatment>
After the second alkali etching treatment, pickling (second desmut treatment) is preferably performed to remove dirt (smut) remaining on the surface. The second desmut process can be performed in the same manner as the first desmut process.
[0114]
In the second desmut treatment, nitric acid or sulfuric acid is preferably used.
In the second desmutting treatment, it is preferable to use an acidic solution containing 1 to 400 g / L of acid and 0.1 to 8 g / L of aluminum ions.
When using sulfuric acid, specifically, use a solution prepared by dissolving aluminum sulfate in an aqueous sulfuric acid solution having a sulfuric acid concentration of 100 to 350 g / L so that the aluminum ion concentration is 0.1 to 5 g / L. Can do. Moreover, the overflow waste liquid of the electrolyte solution used for the anodizing process mentioned later can also be used.
In the second desmut treatment, the treatment time is preferably 1 second or longer, more preferably 4 seconds or longer, and preferably 60 seconds or shorter, more preferably 20 seconds or shorter. .
In the second desmut treatment, the temperature of the acid aqueous solution is preferably 20 ° C. or higher, more preferably 30 ° C. or higher, and preferably 70 ° C. or lower, and preferably 60 ° C. or lower. More preferred.
[0115]
<Second electrolytic treatment (second hydrochloric acid electrolysis)>
The second electrolytic treatment is an electrochemical surface roughening treatment using alternating current or direct current in an aqueous solution containing hydrochloric acid. In the present invention, by combining the first electrolytic treatment described above and the second electrolytic treatment, a complex uneven structure can be formed on the surface of the aluminum plate, and as a result, the printing durability is excellent. can do. Moreover, a 2nd electrolysis process produces | generates a recessed part with an average diameter of 0.01-0.4 micrometer on the aluminum surface smoothed by the 2nd alkali etching. Thereby, printing durability can be enhanced.
[0116]
The second hydrochloric acid electrolysis performed after the first electrolytic treatment is basically the same as described in the first hydrochloric acid electrolysis.
The total amount of electricity that the aluminum plate participates in the anodic reaction by electrochemical surface roughening in an aqueous solution containing hydrochloric acid in the second hydrochloric acid electrolysis is 10 to 10 when the electrochemical surface roughening treatment is completed. 200 C / dm²Can be selected from the range of 10 to 100 C / dm²Is preferred, 50-80 C / dm²Is particularly preferred.
[0117]
When the first hydrochloric acid electrolysis is performed as the first electrolysis treatment, the total amount Q of electricity involved in the anode reaction at the time when the electrolysis reaction in the first hydrochloric acid electrolysis is completed.₁Is the quantity of electricity Q involved in the anode reaction at the time when the electrolytic reaction in the second hydrochloric acid electrolysis is completed.₂Greater than the sum of (Q₁> Q₂) Is preferred. As a result, the surface area of the aluminum plate is increased by the pits having an average opening diameter of 1 to 15 μm generated by the first hydrochloric acid electrolysis, and the adhesiveness with the image recording layer provided thereon is improved and the printing durability is excellent.
[0118]
<Third alkali etching treatment>
The third alkali etching treatment performed after the second electrolytic treatment is performed for the purpose of dissolving the smut generated by the second electrolytic treatment and dissolving the edge portion of the pit formed by the second electrolytic treatment. Is called. Since the third alkali etching process is basically the same as the first alkali etching process, only different points will be described below.
[0119]
In the third alkali etching treatment, the etching amount is 0.05 g / m.²Preferably, it is 0.1 g / m²More preferably, it is 0.3 g / m.²Or less, preferably 0.25 g / m²The following is more preferable. Etching amount is 0.05g / m²When it is as described above, in the non-image portion of the lithographic printing plate, the edge portion of the pit generated by the second hydrochloric acid electrolysis becomes smooth and the ink is not easily caught, so that the stain resistance is excellent. On the other hand, the etching amount is 0.3 g / m.²Since the unevenness | corrugation produced | generated by the 1st hydrochloric acid electrolysis and the 2nd hydrochloric acid electrolysis becomes large as it is the following, printing durability is excellent.
[0120]
In the third alkali etching treatment, the concentration of the alkaline solution is preferably 30 g / L or more, and in order not to make the unevenness caused by the hydrochloric acid alternating current electrolysis in the previous stage too small, the concentration is 100 g / L or less. It is preferable that it is 70 g / L or less.
The alkaline solution preferably contains aluminum ions. The aluminum ion concentration is preferably 1 g / L or more, more preferably 3 g / L or more, and preferably 50 g / L or less, more preferably 8 g / L or less. Such an alkaline solution can be prepared using, for example, water, a 48 mass% sodium hydroxide aqueous solution, and sodium aluminate.
[0121]
In the third alkali etching treatment, the temperature of the alkali solution is preferably 25 ° C or higher, more preferably 30 ° C or higher, and preferably 60 ° C or lower, and 50 ° C or lower. Is more preferable.
In the third alkali etching treatment, the treatment time is preferably 1 second or longer, more preferably 2 seconds or longer, more preferably 30 seconds or shorter, and more preferably 10 seconds or shorter. preferable.
[0122]
<Third desmut treatment>
After the third alkali etching treatment, it is preferable to perform pickling (third desmutting treatment) in order to remove dirt (smut) remaining on the surface. Since the third desmut process is basically the same as the first desmut process, only the differences will be described below.
In the third desmutting process, the same type of liquid as that used in the subsequent anodizing process (for example, sulfuric acid) is used, which eliminates the water washing step between the third desmutting process and the anodizing process. It is preferable in that it can be performed.
In the third desmutting treatment, it is preferable to use an acidic solution containing 5 to 400 g / L acid and 0.5 to 8 g / L aluminum ions. When sulfuric acid is used, specifically, a solution prepared by dissolving aluminum sulfate in a sulfuric acid aqueous solution having a sulfuric acid concentration of 100 to 350 g / L to adjust the aluminum ion concentration to 1 to 5 g / L is preferable.
In the third desmutting treatment, the treatment time is preferably 1 second or longer, more preferably 4 seconds or longer, more preferably 60 seconds or shorter, and more preferably 15 seconds or shorter. .
In the third desmut process, when the same type of electrolyte as that used in the subsequent anodic oxidation process is used as the desmut process liquid, the draining with a nip roller and the water washing process can be omitted after the desmut process.
[0123]
<Anodizing treatment>
The aluminum plate treated as described above is further subjected to anodizing treatment. The anodizing treatment can be performed by a method conventionally used in this field. In this case, for example, in a solution having a sulfuric acid concentration of 50 to 300 g / L and an aluminum concentration of 5% by mass or less, an anodized film can be formed by energizing an aluminum plate as an anode. As a solution used for the anodizing treatment, sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, amidosulfonic acid and the like can be used alone or in combination of two or more.
[0124]
Under the present circumstances, the component normally contained at least in an aluminum plate, an electrode, tap water, groundwater, etc. may be contained in electrolyte solution. Furthermore, the second and third components 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; Cations such as ammonium ion; anions such as nitrate ion, carbonate ion, chloride ion, phosphate ion, fluoride ion, sulfite ion, titanate ion, silicate ion, borate ion, etc., 0 to 10000 ppm It may be contained at a concentration of about.
[0125]
The conditions for anodizing treatment vary depending on the electrolyte used, and thus cannot be determined unconditionally. In general, however, the electrolyte concentration is 1 to 80% by mass, the solution temperature is 5 to 70 ° C., and the current density is 0.5. ~ 60A / dm²It is appropriate that the voltage is 1 to 100 V and the electrolysis time is 15 seconds to 50 minutes, and the anodic oxide film amount is adjusted to a desired amount.
[0126]
Further, JP-A-54-81133, JP-A-57-47894, JP-A-57-51289, JP-A-57-51290, JP-A-57-54300, JP-A-57-136596, JP-A-58-107498, JP-A-60-200366, JP-A-62-136696, JP-A-63-176494, JP-A-4-17697, JP-A-4-280997, JP-A-6-280997 The methods described in JP-A-207299, JP-A-5-24377, JP-A-5-32083, JP-A-5-125597, JP-A-5-195291 and the like can also be used.
[0127]
Of these, as described in JP-A-54-12853 and JP-A-48-45303, it is preferable to use a sulfuric acid solution as the electrolytic solution. The sulfuric acid concentration in the electrolytic solution is preferably 10 to 300 g / L (1 to 30% by mass), more preferably 50 to 200 g / L (5 to 20% by mass), and the aluminum ion concentration. Is preferably 1 to 25 g / L (0.1 to 2.5% by mass), more preferably 2 to 10 g / L (0.2 to 1% by mass). Such an electrolytic solution can be prepared, for example, by adding aluminum sulfate or the like to dilute sulfuric acid having a sulfuric acid concentration of 50 to 200 g / L.
[0128]
The composition management of the electrolyte is conducted using the same method as in the case of nitric acid electrolysis described above, and the conductivity, specific gravity and temperature, or conductivity and ultrasonic wave propagation corresponding to the matrix of sulfuric acid concentration and aluminum ion concentration. It is preferable to control by speed and temperature.
[0129]
The liquid temperature of the electrolytic solution is preferably 25 to 55 ° C, more preferably 30 to 50.
[0130]
When anodizing is performed in an electrolytic solution containing sulfuric acid, direct current may be applied between the aluminum plate and the counter electrode, or alternating current may be applied.
When direct current is applied to the aluminum plate, the current density is 1 to 60 A / dm.²Is preferably 5 to 40 A / dm.²It is more preferable that
In the case of continuous anodizing treatment, at the beginning of anodizing treatment, so as not to cause so-called “burn” (part where the film becomes thicker than the surrounding area) due to current concentration on a part of the aluminum plate, 5-10A / m²30 to 50 A / dm as the anodizing process proceeds at a low current density of²Alternatively, it is preferable to increase the current density further.
Specifically, it is preferable that the current distribution of the DC power supply is set so that the current of the downstream DC power supply is equal to or greater than the current of the upstream DC power supply. By using such current distribution, so-called burning is less likely to occur, and as a result, high-speed anodization can be performed.
[0131]
When the anodizing treatment is continuously performed, it is preferable that the anodizing process is performed by a liquid power feeding method in which power is supplied to the aluminum plate through an electrolytic solution.
By performing anodizing treatment under such conditions, a porous film having many pores called micropores can be obtained. Usually, the average pore diameter is about 5 to 50 nm, and the average pore density is 300. ~ 800 / μm²Degree.
[0132]
The amount of anodized film is 1-5g / m²Is preferred. 1g / m²If it is less than 5%, the plate is likely to be scratched.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 Further, the difference in the amount of the anodized film between the center portion of the aluminum plate and the vicinity of the edge portion is 1 g / m.²It is preferable to carry out as follows.
[0133]
As electrolysis apparatuses used for anodizing treatment, those described in JP-A-48-26638, JP-A-47-18739, JP-B-58-24517, JP-A-2001-11698, etc. Can be used.
Among these, the apparatus shown in FIG. 4 is preferably used. FIG. 4 is a schematic view showing an example of an apparatus for anodizing the surface of an aluminum plate.
[0134]
In the anodizing apparatus 410 shown in FIG. 4, in order to energize the aluminum plate 416 via the electrolytic solution, a power feeding tank 412 is provided upstream in the traveling direction of the aluminum plate 416 and an anodizing tank 414 is provided downstream. It is installed. The aluminum plate 416 is conveyed by the pass rollers 422 and 428 as indicated by arrows in FIG. In the feed tank 412 into which the aluminum plate 416 is first introduced, an anode 420 connected to the positive electrode of the DC power supply 434 is installed, and the aluminum plate 416 serves as a cathode. Therefore, a cathode reaction occurs in the aluminum plate 416.
[0135]
In the anodizing tank 414 into which the aluminum plate 416 is subsequently introduced, a cathode 430 connected to the negative electrode of the DC power source 434 is installed, and the aluminum plate 416 serves as an anode. Therefore, an anodic reaction occurs in the aluminum plate 416, and an anodic oxide film is formed on the surface of the aluminum plate 416.
The distance between the aluminum plate 416 and the cathode 430 is preferably 50 to 200 mm. Aluminum is used as the cathode 430. The cathode 430 is preferably not an electrode having a large area but an electrode divided into a plurality of pieces in the traveling direction of the aluminum plate 416 so that hydrogen gas generated by the anode reaction can be easily released from the system. .
[0136]
Between the power supply tank 412 and the anodizing tank 414, it is preferable to provide a tank called an intermediate tank 413 in which the electrolytic solution does not accumulate as shown in FIG. By providing the intermediate tank 413, current can be prevented from bypassing from the anode 420 to the cathode 430 without passing through the aluminum plate 416. It is preferable to reduce the bypass current as much as possible by installing a nip roller 424 in the intermediate tank 413 to drain the liquid. The electrolyte discharged by draining is discharged out of the anodizing apparatus 410 from the drain port 442.
[0137]
The electrolyte solution 418 stored in the power supply tank 412 has a higher temperature and / or higher concentration than the electrolyte solution 426 stored in the anodizing tank 414 in order to reduce voltage loss. In addition, the composition, temperature, and the like of the electrolytic solutions 418 and 426 are determined from the formation efficiency of the anodized film, the micropore shape of the anodized film, the hardness of the anodized film, the voltage, the cost of the electrolytic solution, and the like.
[0138]
Electrolyte is ejected from the liquid supply nozzles 436 and 438 and supplied to the power supply tank 412 and the anodizing treatment tank 414. For the purpose of keeping the distribution of the electrolyte constant and preventing local current concentration of the aluminum plate 416 in the anodizing tank 414, the liquid supply nozzles 436 and 438 are provided with slits, and the liquid flow to be ejected in the width direction. It has a constant structure.
[0139]
In the anodizing bath 414, a shielding plate 440 is provided on the opposite side of the aluminum plate 416 from the anode 430, and current flows to the opposite side of the surface of the aluminum plate 416 where the anodized film is to be formed. Deter. The distance between the aluminum plate 416 and the shielding plate 440 is preferably 5 to 30 mm. It is preferable to use a plurality of DC power supplies 434 and connect the positive electrode sides in common. Thereby, the current distribution in the anodizing bath 414 can be controlled.
[0140]
<Sealing treatment>
In this invention, you may perform the sealing process which seals the micropore which exists in an anodic oxide film as needed. The sealing treatment can be performed according to a known method such as boiling water treatment, hot water treatment, steam treatment, sodium silicate treatment, nitrite treatment, ammonium acetate treatment and the like. For example, even if the sealing treatment is carried out by the apparatus and method described in JP-B-56-12518, JP-A-4-4194, JP-A-5-20296, JP-A-5-179482, etc. Good.
[0141]
<Hydrophilic treatment>
A hydrophilization treatment may be performed after the anodizing treatment or the sealing treatment. Examples of the hydrophilization treatment include treatment with potassium fluorinated zirconate described in US Pat. No. 2,946,638 and phosphomolybdate described in US Pat. No. 3,201,247. Treatment, alkyl titanate treatment described in British Patent 1,108,559, polyacrylic acid treatment described in German Patent 1,091,433, German Patent 1,134, No. 093 and British Patent No. 1,230,447, polyvinyl phosphonic acid treatment, Japanese Patent Publication No. 44-6409, phosphonic acid treatment, US Pat. No. 3,307,951 Phytic acid treatment described in the specification of JP, No. 58-16893 and JP-A No. 58-18291 Treatment with a salt of a molecular compound and a divalent metal, as described in US Pat. No. 3,860,426, hydrophilic cellulose (eg, zinc acetate) containing a water-soluble metal salt (eg, zinc acetate) Carboxymethyl cellulose) is provided with a subbing layer, and a water-soluble polymer having a sulfo group described in JP-A-59-101651.
[0142]
Further, phosphates described in JP-A No. 62-019494, water-soluble epoxy compounds described in JP-A No. 62-033692, and JP-A No. 62-097892 Phosphate-modified starch, diamine compounds described in JP-A-63-056498, amino acid inorganic or organic acids described in JP-A-63-130391, JP-A-63-145092 Organic phosphonic acids containing carboxy group or hydroxy group, compounds having amino group and phosphonic acid group described in JP-A-63-165183, and JP-A-2-316290 Specific carboxylic acid derivatives, phosphate esters described in JP-A-3-215095, JP-A-3-261592 Compounds having one amino group and one oxygen acid group of phosphorus described in the publication, phosphoric esters described in JP-A-3-215095, and JP-A-5-246171 Aliphatic or aromatic phosphonic acids such as phenylphosphonic acid, compounds containing S atoms such as thiosalicylic acid described in JP-A-1-307745, and phosphorus described in JP-A-4-282737 Examples of the treatment include undercoating using a compound having a group of oxygen acids.
Further, coloring with an acid dye described in JP-A-60-64352 can also be performed.
[0143]
Hydrophilicity can also be achieved by soaking in an aqueous solution of an alkali metal silicate such as sodium silicate or potassium silicate, or by applying a hydrophilic vinyl polymer or hydrophilic compound to form a hydrophilic primer layer. It is preferable to carry out the treatment.
[0144]
Hydrophilization treatment with an aqueous solution of an alkali metal silicate such as sodium silicate and potassium silicate is described in US Pat. No. 2,714,066 and US Pat. No. 3,181,461. It can be performed according to methods and procedures.
Examples of the alkali metal silicate 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.
[0145]
The amount of Si adsorbed by the alkali metal silicate treatment can be 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, the effect of improving the dissolution resistance to the alkaline developer on the surface of the lithographic printing plate support is obtained, the dissolution of the aluminum component into the developer is suppressed, and the developer fatigue It is possible to reduce the occurrence of development residue due to the above.
[0146]
The hydrophilization treatment by forming a hydrophilic undercoat layer can also be performed according to the conditions and procedures described in JP-A Nos. 59-101651 and 60-149491.
Examples of the hydrophilic vinyl polymer used in this method include polyvinyl sulfonic acid, sulfo group-containing vinyl polymerizable compounds such as p-styrene sulfonic acid having a sulfo group, and ordinary vinyl polymerization such as (meth) acrylic acid alkyl ester. And a copolymer with a functional compound. Moreover, as a hydrophilic compound used for this method, for example, —NH₂And a compound having at least one selected from the group consisting of a group, a —COOH group and a sulfo group.
[0147]
<Dry>
After obtaining the lithographic printing plate support as described above, it is preferable to dry the surface of the lithographic printing plate support before providing the image recording layer. Drying is preferably performed after the final treatment of the surface treatment, after washing with water and draining with a nip roller.
The drying temperature is preferably 70 ° C or higher, more preferably 80 ° C or higher, preferably 110 ° C or lower, more preferably 100 ° C or lower.
The drying time is preferably 1 second or more, more preferably 2 seconds or more, preferably 20 seconds or less, and more preferably 15 seconds.
[0148]
<Management of liquid composition>
In the present invention, it is preferable to manage the composition of various processing solutions used for the surface treatment described above by the method described in JP-A-2001-121837. Prepare a large number of treatment liquid samples of various concentrations in advance, measure the ultrasonic wave propagation speed at each of the two liquid temperatures, create a matrix-like data table, It is preferable to measure the propagation speed of the light in real time and control the concentration based on the measurement. In particular, in the desmutting treatment, when an electrolytic solution having a sulfuric acid concentration of 250 g / L or more is used, it is preferable to control the concentration by the method described above.
In addition, it is preferable that each electrolyte solution used for an electrolytic roughening process and an anodic oxidation process is 100 ppm or less of Cu concentration. If the Cu concentration is too high, Cu is deposited on the aluminum plate when the line is stopped, and Cu deposited when the line is operated again may be transferred to a pass roll, which may cause processing unevenness.
[0149]
[Lithographic printing plate precursor]
The lithographic printing plate support obtained by the present invention can be provided with an image recording layer to form the lithographic printing plate precursor of the present invention. A photosensitive composition is used for the image recording layer.
Examples of the photosensitive composition suitably used in the present invention include a thermal positive photosensitive composition containing an alkali-soluble polymer compound and a photothermal conversion substance (hereinafter, this composition and an image recording layer using the same). ), A thermal negative photosensitive composition containing a curable compound and a photothermal conversion substance (hereinafter also referred to as “thermal negative type”), a photopolymerizable photosensitive composition (hereinafter referred to as “thermal positive type”). , Also referred to as “photopolymer type”), negative photosensitive composition containing diazo resin or photocrosslinking resin (hereinafter also referred to as “conventional negative type”), and positive photosensitive composition containing quinonediazide compound. Product (hereinafter also referred to as "conventional positive type"), photosensitive composition that does not require a special development step (hereinafter referred to as As the referred to as "non-treatment type".), And the like. Hereinafter, these suitable photosensitive compositions will be described.
[0150]
<Thermal positive type>
<Photosensitive layer>
The thermal positive type photosensitive composition contains an alkali-soluble polymer compound and a photothermal conversion substance. In the thermal positive type image recording layer, the photothermal conversion substance converts the energy of light such as infrared lasers into heat, which effectively eliminates the interaction that reduces the alkali solubility of alkali-soluble polymer compounds. To do.
[0151]
Examples of the alkali-soluble polymer compound include a resin containing an acidic group in the molecule and a mixture of two or more thereof. In particular, phenolic hydroxy groups, sulfonamide groups (-SO₂NH-R (wherein R represents a hydrocarbon group)), an active imino group (-SO₂NHCOR, -SO₂NHSO₂R, -CONHSO₂A resin having an acidic group such as R (wherein R has the same meaning as described above)) is preferable in terms of solubility in an alkali developer.
In particular, a resin having a phenolic hydroxy group is preferable in that it has excellent image-forming properties when exposed to light such as an infrared laser, and examples thereof include phenol-formaldehyde resins, m-cresol-formaldehyde resins, p-cresol-formaldehyde resins, m- / p-mixed cresol-formaldehyde resin, phenol / cresol (any of m-, p- and m- / p-mixed) mixed-formaldehyde resin (phenol-cresol-formaldehyde co-condensation resin) and other novolak resins Are preferable.
Furthermore, the polymer compound described in JP-A No. 2001-305722 (particularly [0023] to [0042]), and the repetition represented by the general formula (1) described in JP-A No. 2001-215893 Preferred examples also include polymer compounds containing units, and polymer compounds described in JP-A No. 2002-311570 (particularly [0107]).
[0152]
Preferable examples of the photothermal conversion substance include pigments or dyes having a light absorption region in the infrared region having a wavelength of 700 to 1200 nm from the viewpoint of recording sensitivity. Examples of the dye include azo dyes, metal complex azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinoneimine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, metal thiolate complexes (for example, , Nickel thiolate complex). Among these, cyanine dyes are preferable, and cyanine dyes represented by the general formula (I) described in JP 2001-305722 A are particularly preferable.
[0153]
The thermal positive type photosensitive composition may contain a dissolution inhibitor. As the dissolution inhibitor, for example, dissolution inhibitors described in JP-A-2001-305722, [0053] to [0055] are preferably exemplified.
In addition, in the thermal positive type photosensitive composition, as a additive, a sensitivity modifier, a printing agent for obtaining a visible image immediately after heating by exposure, a compound such as a dye as an image colorant, a coating property In addition, it is preferable to include a surfactant for improving the processing stability. For these, compounds described in JP-A-2001-305722, [0056] to [0060] are preferable.
The photosensitive composition described in detail by Unexamined-Japanese-Patent No. 2001-305722 is preferably used also in respects other than the above.
[0154]
Further, the thermal positive type image recording layer is not limited to a single layer but may have a two-layer structure.
As an image recording layer having a two-layer structure (multilayer image recording layer), a lower layer (hereinafter referred to as “A layer”) having excellent printing durability and solvent resistance is provided on the side close to the support, and a positive layer is provided thereon. A type provided with a layer having excellent image formability (hereinafter referred to as “B layer”) is preferable. This type has high sensitivity and can realize a wide development latitude. The B layer generally contains a photothermal conversion substance. Preferred examples of the photothermal conversion substance include the dyes described above.
As the resin used in the A layer, a polymer having a monomer having a sulfonamide group, an active imino group, a phenolic hydroxy group or the like as a copolymerization component is preferably used because it has excellent printing durability and solvent resistance. . As the resin used for the B layer, an alkaline aqueous solution-soluble resin having a phenolic hydroxy group is preferably exemplified.
In addition to the resin, the composition used for the A layer and the B layer can contain various additives as necessary. Specifically, various additives as described in JP-A-2002-3233769, [0062] to [0085] are preferably used. Further, the additives described in [0053] to [0060] of JP-A-2001-305722 described above are also preferably used.
About each component which comprises A layer and B layer, and its content, it is preferable to make it describe in Unexamined-Japanese-Patent No. 11-218914.
[0155]
<Intermediate layer>
An intermediate layer is preferably provided between the thermal positive type image recording layer and the support. As the component contained in the intermediate layer, various organic compounds described in [0068] of JP-A No. 2001-305722 are preferably exemplified.
[0156]
<Others>
As a method for producing a thermal positive type image recording layer and a plate making method, methods described in detail in JP-A No. 2001-305722 can be used.
[0157]
<Thermal negative type>
The thermal negative photosensitive composition contains a curable compound and a photothermal conversion substance. The thermal negative type image recording layer is a negative photosensitive layer in which a portion irradiated with light such as an infrared laser is cured to form an image portion.
<Polymerized layer>
As one of the thermal negative type image recording layers, a polymerization type image recording layer (polymerization layer) is preferably exemplified. The polymerization layer contains a photothermal conversion substance, a radical generator, a radical polymerizable compound that is a curable compound, and a binder polymer. In the polymerization layer, infrared light absorbed by the light-to-heat conversion substance is converted into heat, the radical generator is decomposed by this heat to generate radicals, and the radical polymerizable compound is polymerized in a chain by the generated radicals and cured. .
[0158]
As a photothermal conversion substance, the photothermal conversion substance used for the thermal positive type mentioned above is mentioned, for example. Specific examples of particularly preferred cyanine dyes include those described in JP-A-2001-133969, [0017] to [0019].
Preferred examples of the radical generator include onium salts. In particular, onium salts described in JP-A-2001-133969, [0030] to [0033] are preferable.
Examples of the radical polymerizable compound include compounds having at least one terminal ethylenically unsaturated bond, preferably two or more.
As the binder polymer, a linear organic polymer is preferably exemplified. Preferred examples include linear organic polymers that are soluble or swellable in water or weak alkaline water. Among them, a (meth) acrylic resin having an unsaturated group such as an allyl group or an acryloyl group or a benzyl group and a carboxy group in the side chain is preferable in that it has an excellent balance of film strength, sensitivity, and developability. .
As the radical polymerizable compound and the binder polymer, those described in detail in [0036] to [0060] of JP-A No. 2001-133969 can be used.
[0159]
The additive described in [0061] to [0068] of JP-A No. 2001-133969 is contained in the thermal negative photosensitive composition (for example, a surfactant for improving coatability). Is preferred.
[0160]
As a method for producing the polymerization layer and a plate making method, methods described in detail in JP-A No. 2001-133969 can be used.
[0161]
<Acid cross-linked layer>
Further, as one of the thermal negative type image recording layers, an acid cross-linked image recording layer (acid cross-linked layer) is also preferably exemplified. The acid cross-linking layer comprises a photothermal conversion substance, a thermal acid generator, a compound that cross-links with an acid that is a curable compound (cross-linking agent), and an alkali-soluble polymer compound that can react with the cross-linking agent in the presence of an acid. contains. In the acid cross-linking layer, infrared light absorbed by the photothermal conversion substance is converted into heat, the heat acid generator is decomposed by this heat to generate an acid, and the generated acid reacts with the cross-linking agent and the alkali-soluble polymer compound. And harden.
[0162]
Examples of the photothermal conversion substance include the same substances as those used for the polymerization layer.
Examples of the thermal acid generator include thermal decomposition compounds such as photoinitiators for photopolymerization, photochromic agents for dyes, and acid generators used in microresists.
Examples of the crosslinking agent include an aromatic compound substituted with a hydroxymethyl group or an alkoxymethyl group; a compound having an N-hydroxymethyl group, an N-alkoxymethyl group or an N-acyloxymethyl group; and an epoxy compound.
Examples of the alkali-soluble polymer compound include a novolak resin and a polymer having a hydroxyaryl group in the side chain.
[0163]
<Photopolymer type>
The photopolymerization type photosensitive composition contains an addition polymerizable compound, a photopolymerization initiator, and a polymer binder.
As the addition polymerizable compound, an ethylenically unsaturated bond-containing compound capable of addition polymerization is preferably exemplified. The ethylenically unsaturated bond-containing compound is a compound having a terminal ethylenically unsaturated bond. Specifically, for example, it has a chemical form such as a monomer, a prepolymer, and a mixture thereof. Examples of monomers include esters of unsaturated carboxylic acids (eg, acrylic acid, methacrylic acid, itaconic acid, maleic acid) and aliphatic polyhydric alcohol compounds, amides of unsaturated carboxylic acids and aliphatic polyvalent amine compounds. Is mentioned.
Moreover, as an addition polymerizable compound, a urethane type addition polymerizable compound is also preferably exemplified.
[0164]
As the photopolymerization initiator, various photopolymerization initiators or a combination system (photoinitiation system) of two or more kinds of photopolymerization initiators can be appropriately selected depending on the wavelength of the light source to be used. For example, an initiation system described in JP-A-2001-22079, [0021] to [0023] is preferably exemplified.
The polymer binder not only functions as a film-forming agent for the photopolymerization type photosensitive composition, but is soluble or swellable in alkaline water because it is necessary to dissolve the image recording layer in an alkaline developer. An organic high molecular polymer is used. As such an organic polymer, those described in JP-A-2001-22079, [0036] to [0063] are preferably exemplified.
[0165]
In the photopolymer type photopolymerization type photosensitive composition, additives described in JP-A-2001-22079, [0079] to [0088] (for example, a surfactant for improving coatability) , Colorants, plasticizers, thermal polymerization inhibitors).
[0166]
Further, it is preferable to provide an oxygen-blocking protective layer on the photopolymer type image recording layer in order to prevent the action of inhibiting the polymerization of oxygen. Examples of the polymer contained in the oxygen barrier protective layer include polyvinyl alcohol and copolymers thereof.
Furthermore, it is also preferable to provide an intermediate layer or an adhesive layer as described in [0124] to [0165] of JP-A-2001-228608.
[0167]
<Conventional negative type>
The conventional negative-type photosensitive composition contains a diazo resin or a photocrosslinking resin. Among these, a photosensitive composition containing a diazo resin and an alkali-soluble or swellable polymer compound (binder) is preferable.
Examples of the diazo resin include condensates of aromatic diazonium salts and active carbonyl group-containing compounds such as formaldehyde; condensates of p-diazophenylamines and formaldehyde with hexafluorophosphate or tetrafluoroborate. Organic solvent-soluble diazo resin inorganic salts which are reaction products of In particular, a high molecular weight diazo compound containing 20 mol% or more of a hexamer described in JP-A-59-78340 is preferable.
Examples of the binder include a copolymer containing acrylic acid, methacrylic acid, crotonic acid, or maleic acid as an essential component. Specifically, a multi-component copolymer of monomers such as 2-hydroxyethyl (meth) acrylate, (meth) acrylonitrile, (meth) acrylic acid as described in JP-A-50-118802, Examples thereof include multi-component copolymers composed of alkyl acrylate, (meth) acrylonitrile and unsaturated carboxylic acid as described in JP-A-56-4144.
[0168]
The conventional negative type photosensitive composition has, as an additive, a printing agent, dye, and flexibility and abrasion resistance described in JP-A-7-281425, [0014] to [0015]. It is preferable to contain a plasticizer for imparting, a compound such as a development accelerator, and a surfactant for improving coating properties.
[0169]
Under the conventional negative type photosensitive layer, 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 is provided. Is preferred.
[0170]
<Conventional positive type>
The conventional positive-type photosensitive composition contains a quinonediazide compound. Among these, a photosensitive composition containing an o-quinonediazide compound and an alkali-soluble polymer compound is preferable.
Examples of the o-quinonediazide compound include esters of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and phenol-formaldehyde resin or cresol-formaldehyde resin, described in US Pat. No. 3,635,709. And esters of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and pyrogallol-acetone resin.
Examples of the alkali-soluble polymer compound include phenol-formaldehyde resin, cresol-formaldehyde resin, phenol-cresol-formaldehyde co-condensation resin, polyhydroxystyrene, N- (4-hydroxyphenyl) methacrylamide copolymer, A carboxy group-containing polymer described in JP-A-7-36184, an acrylic resin containing a phenolic hydroxy group as described in JP-A-51-34711, and described in JP-A-2-866 Examples thereof include acrylic resins having a sulfonamide group and urethane resins.
[0171]
Conventional positive type photosensitive compositions include compounds such as sensitivity modifiers, printing agents, dyes and the like described in JP-A-7-92660, [0024] to [0027] as additives. It is preferable to contain a surfactant for improving the coating property as described in [0031] of Kaihei 7-92660.
[0172]
Under the conventional positive type photosensitive layer, it is preferable to provide an intermediate layer similar to the intermediate layer suitably used for the above-described conventional negative type.
[0173]
<Non-treatment type>
Examples of the non-processing type photosensitive composition include a thermoplastic fine particle polymer type, a microcapsule type, and a sulfonic acid-generating polymer-containing type. These are all heat-sensitive types containing a photothermal conversion substance. The photothermal conversion substance is preferably the same dye as that used in the above-described thermal positive type.
[0174]
The thermoplastic fine particle polymer type photosensitive composition is obtained by dispersing a hydrophobic and heat-meltable fine particle polymer in a hydrophilic polymer matrix. In the image recording layer of the thermoplastic fine particle polymer type, the hydrophobic fine particle polymer is melted by heat generated by exposure and is fused to form a hydrophobic region, that is, an image portion.
As the fine particle polymer, those in which fine particles melt and coalesce with heat are preferable, and those having a hydrophilic surface and capable of being dispersed in a hydrophilic component such as dampening water are more preferable. Specifically, Research Disclosure No. 33303 (January 1992), JP-A-9-123387, JP-A-9-131850, JP-A-9-171249, and JP-A-9-171250, and European Patent Application Publication No. 931,647. Preferred examples thereof include thermoplastic fine particle polymers. Of these, polystyrene and polymethyl methacrylate are preferred. Examples of the fine particle polymer having a hydrophilic surface include those in which the polymer itself is hydrophilic; those in which a hydrophilic compound such as polyvinyl alcohol and polyethylene glycol is adsorbed on the surface of the fine particle polymer to make the surface hydrophilic.
The fine particle polymer preferably has a reactive functional group.
[0175]
As a microcapsule type photosensitive composition, a compound having a heat-reactive functional group as described in JP-A No. 2000-118160 or JP-A No. 2001-277740 is included. A microcapsule type is preferable.
[0176]
Examples of the sulfonic acid generating polymer used in the sulfonic acid generating polymer-containing photosensitive composition include sulfonic acid ester groups, disulfone groups, and sec- or tert-sulfonamides described in JP-A No. 10-282672. Examples thereof include polymers having a group in the side chain.
[0177]
By incorporating a hydrophilic resin into the unprocessed photosensitive composition, not only on-press developability is improved, but also the film strength of the photosensitive layer itself is improved. Examples of the hydrophilic resin include those having a hydrophilic group such as hydroxy group, carboxy group, hydroxyethyl group, hydroxypropyl group, amino group, aminoethyl group, aminopropyl group, carboxymethyl group, and hydrophilic sol-gel conversion system. A binder resin is preferred.
[0178]
The unprocessed type image recording layer does not require a special development step and can be developed on a printing press. As a method for producing an unprocessed image recording layer and a plate-making printing method, methods described in detail in JP-A No. 2002-178655 can be used.
[0179]
<Back coat>
In this way, the backside of the lithographic printing plate precursor of the present invention obtained by providing various image recording layers on the lithographic printing plate support obtained by the present invention, if necessary, is an image in the case of overlapping. In order to prevent the recording layer from being damaged, a coating layer made of an organic polymer compound can be provided.
[0180]
[Plate making method (lithographic printing plate production method)]
The lithographic printing plate precursor using the lithographic printing plate support obtained by the present invention is converted into a lithographic printing plate by various treatment methods according to the image recording layer.
Examples of the actinic ray light source used for image exposure include a mercury lamp, a metal halide lamp, a xenon lamp, and a chemical lamp. Examples of the laser beam include helium-neon laser (He-Ne laser), argon laser, krypton laser, helium-cadmium laser, KrF excimer laser, semiconductor laser, YAG laser, and YAG-SHG laser.
[0181]
After the above exposure, if the image recording layer is any of thermal positive type, thermal negative type, conventional negative type, conventional positive type, and photopolymer type, after exposure, it is developed using a developer to obtain a lithographic printing plate. It is preferable to obtain.
The developer is preferably an alkaline developer, and more preferably an alkaline aqueous solution substantially free of an organic solvent.
Moreover, the developing solution which does not contain alkali metal silicate substantially is also preferable. As a method of developing using a developer substantially not containing an alkali metal silicate, a method described in detail in JP-A No. 11-109637 can be used.
A developer containing an alkali metal silicate can also be used.
[0182]
【Example】
EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
1. Fabrication of aluminum plate
<Aluminum plates 1-3, comparative aluminum plate 1>
[0183]
A molten metal was prepared using three types of used beverage cans (UBC) ingots, subjected to molten metal treatment and filtration, and an ingot having a thickness of 500 mm and a width of 1200 mm was prepared by a DC casting method. 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. Furthermore, heat treatment was performed at 500 ° C. using a continuous annealing machine. In the subsequent cold rolling, the surface of the rolling roll is roughened by shot blasting to form an uneven surface, and then the uneven surface of the rolling roll is hardened by rolling the uneven surface hard chrome-plated. The concavo-convex pattern was transferred by pressure-contacting to an aluminum plate. Then, it finished to thickness 0.3mm and width 1060mm, and obtained the aluminum plates 1-3. The respective compositions are shown in Table 1.
For comparison, a comparative aluminum plate 1 was obtained by subjecting an aluminum material having a composition of JIS A 1050 to the same treatment as described above. The composition is shown in Table 1 as a comparative plate 1.
[0184]
2. Evaluation of aluminum plate
(1) Average roughness R of the surface of the aluminum plate_a
Two-dimensional roughness is measured with a stylus type roughness meter (SUFCOM 575, manufactured by Tokyo Seimitsu Co., Ltd.), and the average roughness R defined in ISO 4287 is measured._aWas measured 5 times, and the average value was defined as the average roughness. The results are shown in Table 1.
The conditions for the two-dimensional roughness measurement are shown below.
<Measurement conditions>
Cut-off value 0.8mm, tilt correction FLAT-ML, measurement length 3mm, vertical magnification 10000 times, scanning speed 0.3mm / sec, stylus tip diameter 2μm
[0185]
(2) Measurement of major and minor diameters of recesses and calculation of average length ratio
The major axis of the ellipse formed on the surface of each aluminum plate is measured using a scanning electron microscope (JSM-5500, manufactured by JEOL Ltd.) at a magnification of 750 times from the top of the aluminum plate. In the obtained electron micrograph, 50 oval concave portions were extracted, the diameter of each concave portion in the major axis direction was read, and the average value thereof was defined as the average major axis (major axis). The minor axis (minor axis) was calculated in the same manner.
The average length ratio was obtained by calculating the ratio of the major axis to the minor axis (length ratio) of the 50 recesses read above, and calculating the average value of the ratios of the 50 ratios. .
[0186]
When the concavo-convex pattern obtained by the transfer was evaluated under the above conditions, an ellipse-shaped recess was formed, the average major axis was 5-25 μm, the average minor axis was 5-15 μm, and the ellipse-shaped recess The average ratio of the major axis to the minor axis (major axis / minor axis) was 2.2, and the average surface roughness was 0.5 μm.
(3) Cost of aluminum plate
Since the comparative aluminum plate 1 adjusts the components of the aluminum plate, the energy cost to manufacture the aluminum plate was about 10% or more higher than the aluminum plate 1 (Evaluation A) (Evaluation B). The results are shown in Table 2 as the aluminum cost of the lithographic printing plate.
[0187]
[Table 1]

[0188]
3. Production of lithographic printing plate support
<Support Examples 1 to 3 and Support Comparative Example 1>
Each obtained aluminum plate was subjected to the following surface treatment to obtain lithographic printing plate supports 1 to 6 and comparative support 1.
<Surface treatment>
The surface treatment was performed by continuously performing the following various treatments (a) to (j).
[0189]
(A) Etching treatment in alkaline aqueous solution (first)
An etching process was performed by spraying an aqueous solution of caustic soda concentration of 370 g / L, aluminum ion concentration of 100 g / L, and a temperature of 60 ° C. onto the aluminum plate from a spray tube. The etching amount of the surface subjected to electrochemical roughening after the aluminum plate is 3 g / m.²Met.
Thereafter, the liquid was drained with a nip roller, and further, a water washing treatment described later was performed, and then the liquid was drained with a nip roller. Washing with water is performed by using a device for washing with a free-falling curtain-like liquid film shown in FIG. 1, and further using a spray tube having a structure having spray tips with fan-sprays spread at intervals of 80 mm. Washed with water for 2 seconds.
[0190]
(B) Desmutting treatment in acidic aqueous solution (first)
A desmut treatment was performed by spraying an aqueous nitric acid solution having a temperature of 35 ° C. for 5 seconds from a spray tube. As the nitric acid aqueous solution, the waste liquid of the electrochemical surface-roughening treatment step using (c) alternating current in nitric acid aqueous solution described later was used.
Then, without carrying out liquid removal with a nip roller, it conveyed in the state which nitric acid aqueous solution adhered to the aluminum plate. The conveyance time was 25 seconds.
[0191]
(C) Electrochemical roughening treatment using alternating current in aqueous nitric acid (first electrolytic treatment)
Immediately before the electrochemical surface roughening treatment, an electrolytic solution having the same composition and temperature as the electrolytic solution used for nitric acid electrolysis described later was sprayed onto the aluminum plate.
Then, using an electrolytic solution (liquid temperature 50 ° C.) in which aluminum nitrate is dissolved in an aqueous solution of 11.0 g / L nitric acid to have an aluminum ion concentration of 4.5 g / L, electrochemical is continuously performed using an alternating voltage of 60 Hz. Roughening treatment was performed. The AC power supply waveform is the waveform shown in FIG. 2, and the time TP until the current value reaches the peak from zero was 0.8 msec, and the duty ratio (ta / T) was 0.5. A carbon electrode was used as the counter electrode. Ferrite was used for the auxiliary anode. Two electrolytic cells shown in FIG. 3 were used.
In the electrochemical surface roughening treatment, the current density during the anode reaction of the aluminum plate at the peak of alternating current is 60 A / dm.²Met. The ratio of the total amount of electricity during the anode reaction of the aluminum plate to the total amount of electricity during the cathode reaction was 0.95. The amount of electricity is the total amount of electricity when the anode of the aluminum plate is 200 C / dm²Met. 5% of the current flowing from the power source was shunted to the auxiliary anode. The relative speed of the aluminum plate and the electrolytic solution was 1.5 m / sec on average in the electrolytic cell.
Thereafter, the liquid was drained by a nip roller, and further, the water was washed using a spray tube having the same structure as that used in the water washing process of (a) above, and then the liquid was drained by a nip roller.
[0192]
(D) Etching treatment in alkaline aqueous solution (second)
The aluminum plate was etched for 7 seconds by spraying an aqueous solution having a caustic soda concentration of 370 g / L, an aluminum ion concentration of 100 g / L, and a temperature of 64 ° C. from a spray tube. The etching amount of the surface to be electrochemically roughened in the subsequent process is 3 g / m²Met.
Thereafter, the liquid was drained with a nip roller, and further, a water washing treatment described later was performed, and then the liquid was drained with a nip roller. The water washing treatment is to wash with water using an apparatus for washing with a free-fall curtain-like liquid film, and further with water for 5 seconds using a spray tube having the same structure as that used in the water washing treatment of (a) above. It went by.
[0193]
(E) Desmutting treatment in acidic aqueous solution (second)
A desmut treatment was performed by spraying an aqueous solution (liquid temperature 35 ° C.) in which aluminum nitrate was dissolved in an aqueous solution of 300 g / L of sulfuric acid and having an aluminum ion concentration of 2 g / L from the spray tube for 10 seconds.
Thereafter, the liquid was drained with a nip roller, washed with water, and further drained with a nip roller.
[0194]
(F) Electrochemical roughening treatment using alternating current in aqueous hydrochloric acid (second electrolytic treatment)
Using an electrolytic solution in which aluminum chloride is dissolved in an aqueous solution having a liquid temperature of 35 ° C. and a hydrochloric acid concentration of 5 g / L to make an aluminum ion concentration of 5 g / L, a power source that generates a trapezoidal wave alternating current is used. Then, the electrochemical surface roughening treatment was performed continuously. The time TP until the current value reached the peak from zero was 0.8 msec, and the duty ratio (ta / T) was 0.5. A carbon electrode was used as the counter electrode. Ferrite was used for the auxiliary anode. One electrolytic cell shown in FIG. 3 was used.
In the electrochemical surface roughening treatment, the current density during the anode reaction of the aluminum plate at the peak of alternating current is 50 A / dm.²Met. The ratio of the total amount of electricity during the anode reaction of the aluminum plate to the total amount of electricity during the cathode reaction was 0.95. The amount of electricity is the sum of the amount of electricity when the anode of the aluminum plate is 63 C / dm²Met. 5% of the current flowing from the power source was shunted to the auxiliary anode. The relative speed of the aluminum plate and the electrolytic solution was 1.5 m / sec on average in the electrolytic cell.
Thereafter, the liquid was drained with a nip roller, washed with water, and further drained with a nip roller.
[0195]
(G) Etching treatment in aqueous alkali solution (third)
An etching process was performed by spraying an aqueous solution of caustic soda concentration of 50 g / L, aluminum ion concentration of 5 g / L, and a temperature of 35 ° C. on the aluminum plate from a spray tube. The etching amount of the surface subjected to the electrochemical roughening treatment of the aluminum plate is 0.1 g / m.²Met.
Thereafter, the liquid was drained with a nip roller, and further, a water washing treatment described later was performed, and then the liquid was drained with a nip roller. The water washing treatment is to wash with water using an apparatus for washing with a free-fall curtain-like liquid film, and further with water for 5 seconds using a spray tube having the same structure as that used in the water washing treatment of (a) above. It went by.
[0196]
(H) Desmutting treatment in acidic aqueous solution (third)
As the aqueous solution, a desmut treatment was performed by spraying from a spray tube for 5 seconds using (i) anodizing waste solution (sulfuric acid concentration 170 g / L, aluminum ion concentration 5 g / L, liquid temperature 35 ° C.) described later. .
Thereafter, the liquid was drained with a nip roller, but after the liquid was drained with a nip roller, no water washing treatment was performed until anodization was performed.
[0197]
(I) Anodizing treatment
Anodizing was performed using the anodizing apparatus shown in FIG.
As the electrolytic solution, an electrolytic solution (temperature 33 ° C.) in which aluminum sulfate was dissolved in a 170 g / L sulfuric acid aqueous solution to make the aluminum ion concentration 5 g / L was used. In the anodizing treatment, the average current density during the anodic reaction of the aluminum plate (about 16 seconds) is 15 A / dm.²The final oxide film amount is 2.4 g / m.²Met. The time for the aluminum plate to participate in the anodic reaction was 16 seconds.
Thereafter, the liquid was drained with a nip roller, washed with water, and further drained with a nip roller.
[0198]
(J) Hydrophilization treatment
The aluminum plate was immersed in a 2.5% by mass aqueous solution of sodium silicate (liquid temperature 20 ° C.) for 10 seconds. The amount of Si on the surface of the aluminum plate measured with a fluorescent X-ray analyzer was 3.5 mg / m.²Met.
Thereafter, the liquid was drained with a nip roller, washed with water, and further drained with a nip roller. Furthermore, 90 degreeC wind was sprayed for 10 seconds, it was made to dry, and the lithographic printing plate support Examples 1-3 were obtained.
[0199]
<Support Example 4>
A lithographic printing plate was prepared in the same manner as in Support Example 1 except that the aluminum plate used in Support Example 1 was used and the conditions of the roughening treatments (a) to (d) were changed to the following conditions. A support 4 was obtained.
(A-2) Etching treatment in alkaline aqueous solution (first)
Among the above conditions (a), the etching amount of the surface subjected to the electrochemical roughening after the aluminum plate is 2 g / m.²(A) The same process as the etching process (first) in an alkaline aqueous solution was performed.
[0200]
(B-2) Desmut treatment in acidic aqueous solution (first)
Of the above conditions (b), the same treatment as the desmutting treatment (first) in the acidic aqueous solution (first) was performed except that the last conveying time was 10 seconds.
[0201]
(C-2) Electrochemical roughening treatment using alternating current in aqueous hydrochloric acid (first electrolytic treatment)
In the above (c), the electrochemical surface roughening treatment was performed in an aqueous nitric acid solution. In the support example 4, the electrochemical surface roughening treatment using alternating current in an aqueous hydrochloric acid solution under the following conditions was performed. The first electrolytic treatment was performed.
Using an electrolytic solution in which aluminum chloride is dissolved in an aqueous solution having a liquid temperature of 35 ° C. and a hydrochloric acid concentration of 7.5 g / L to have an aluminum ion concentration of 4.5 g / L, a power source that generates a sine wave alternating current is used. The electrochemical surface roughening treatment was performed continuously using the frequency of. The duty ratio (ta / T) was 0.5. A carbon electrode was used as the counter electrode. Ferrite was used for the auxiliary anode. Two electrolytic cells shown in FIG. 3 were used.
In the electrochemical surface roughening treatment, the current density during the anode reaction of the aluminum plate at the peak of alternating current is 60 A / dm.²Met. The ratio of the total amount of electricity during the anode reaction of the aluminum plate to the total amount of electricity during the cathode reaction was 0.95. The amount of electricity is the sum of the amount of electricity when the anode of the aluminum plate is 250 C / dm²Met. 5% of the current flowing from the power source was shunted to the auxiliary anode. The relative speed of the aluminum plate and the electrolytic solution was 1.5 m / sec (1-2 m / sec) on average in the electrolytic cell.
Thereafter, the liquid was drained with a nip roller, washed with water, and further drained with a nip roller.
[0202]
(D-2) Etching treatment in alkaline aqueous solution (second)
Of the conditions of (d) above, the etching amount of the surface to be electrochemically roughened in the subsequent step is 1 g / m.²Except for the above, (d) the same treatment as the etching treatment (second) in an alkaline aqueous solution was performed.
[0203]
<Support Example 5>
Using an aluminum plate having the same composition and concavo-convex pattern as in Support Example 1, before (a) the etching treatment (first) in the alkaline aqueous solution of Support Example 1, the following (k) mechanical A roughening treatment was performed. The surface treatments (a) to (j) were performed in the same manner as in Support Example 1, and then dried in the same manner to produce a lithographic printing plate support 5.
[0204]
(K) Mechanical roughening treatment using a brush and an abrasive
A suspension obtained by suspending pumiceton having a specific gravity of 1.13 (average particle size of 30 μm) in water is used as a polishing slurry liquid, and a single rotating brush is used so that Ra after roughening becomes 0.58 μm. Mechanical roughening was performed at a brush rotational speed of 250 rpm.
[0205]
As the roller-shaped brush, use is made of 6/10 nylon bristles with a bristles length of 50 mm and bristles diameter of 0.295 mm, which are planted so as to be dense by making holes on the surface of a 300 mm diameter stainless steel roller. It was.
As the two supporting rollers under the brush, a stainless steel roller having a diameter of 200 mm was used at a distance of 300 mm between the centers.
[0206]
The roller-like brush is pressed with a pressure of 7 kW plus against the load before the brush motor is pressed against the aluminum plate, and the rotation direction on the roughened surface is the conveyance direction of the aluminum web W. It was rotated to be in the same direction.
[0207]
The concentration of the abrasive was continuously obtained from the temperature and specific gravity of the abrasive slurry, and mechanical surface roughening was performed while replenishing the slurry collection tank with water and pumiston so that the concentration was constant. Further, the pumicestone pulverized and refined in the mechanical surface roughening was removed by a classifier in the particle diameter adjusting unit so that the particle size distribution of the pamiston in the abrasive slurry was substantially constant. A cyclone was used as the classifier.
[0208]
<Support Example 6>
Using an aluminum plate having the same composition and concavo-convex pattern as Support Example 4 and before (a-2) etching treatment (first) in an alkaline aqueous solution of Support Example 4 (k) The mechanical surface roughening treatment was similarly performed so that Ra after the surface roughening was 0.58 μm. Surface treatments (a-2) to (d-2) to (e) to (j) were performed in the same manner as in Support Example 4, and then dried in the same manner to produce a lithographic printing plate support 6. .
[0209]
<Support Comparative Example 1>
Using the aluminum having the composition of JIS A 1050, the same uneven pattern as in Support Example 1 was transferred during the final rolling of the cold rolling in the same manner as in Support Example 1. Thereafter, a comparative aluminum plate 1 having a thickness of 0.3 mm and a width of 1060 mm is finished, and the roughening treatments (a) to (j) are performed in the same manner as in Support Example 1, so that the comparative lithographic printing plate support 1 is obtained. Obtained.
[0210]
<Support Comparative Example 2>
As in Support Example 5, except that the uneven pattern was not transferred, and (k) an aluminum plate treated so that Ra after mechanical roughening was 0.58 μm only by mechanical roughening treatment. Then, roughening treatments (a) to (j) were carried out in the same manner as in Support Example 5 to obtain a comparative lithographic printing plate support 2.
[0211]
4). Evaluation of lithographic printing plate support
(1) Surface shape
The surface shapes of the obtained lithographic printing plate supports 1-6 and comparative supports 1-2 were observed with a scanning electron microscope (JSM-5500, manufactured by JEOL Ltd., the same shall apply hereinafter) at a magnification of 50000 times. On the surface, fine irregularities having a diameter of 0.1 μm were generated uniformly and densely. Further, when observed with a scanning electron microscope at a magnification of 2000, irregularities having a diameter of 1 to 5 μm were formed on the surface of the aluminum plate. The fine irregularities having a diameter of 0.1 μm were generated by being superimposed on the irregularities having a diameter of 1 to 5 μm.
In addition, as for the surface shape of the comparison support body 2, the fine unevenness | corrugation with a diameter of 0.1 micrometer produced | generated uniformly and densely on the surface. Further, irregularities having a diameter of 1 to 15 μm were formed on the surface of the aluminum plate. The fine irregularities having a diameter of 0.1 μm were generated by being superimposed on the irregularities having a diameter of 1 to 15 μm.
[0212]
(2) Observation of chatter marks on the surface of a lithographic printing plate support (uneven support processing)
The surface of each lithographic printing plate support was observed with the naked eye, and the degree of chatter marks was sensory evaluated. The results are shown in Table 2. In the table, “A” indicates that there was no chatter mark, “A-B” indicates that there was no chatter mark, “B” indicates that there was no problem, but “C” indicates that there was no problem.
[0213]
5. Preparation of lithographic printing plate precursor
Each of the lithographic printing plate supports 1 to 6 and the comparative supports 1 and 2 obtained as described above is provided with a thermal positive type image recording layer as described below to provide a lithographic printing plate precursor (Examples 1 to 6, Comparative examples 1 and 2) were obtained. Before providing the image recording layer, an undercoat layer was provided as described later.
[0214]
An undercoat solution having the following composition was applied onto a lithographic printing plate support and dried at 80 ° C. for 15 seconds to form a coating film of an undercoat layer. The coating amount after drying is 15 mg / m²Met.
[0215]
<Undercoat liquid composition>
・ The following polymer compound 0.3g
・ Methanol 100g
・ Water 1g
[0216]
[Chemical 1]

[0217]
Furthermore, a heat-sensitive layer coating solution having the following composition was prepared, and the coating amount after drying the heat-sensitive layer coating solution (heat-sensitive layer coating amount) on a lithographic printing plate support provided with an undercoat layer was 1.8 g / m.²And dried to form a heat sensitive layer (thermal positive type image recording layer) to obtain a lithographic printing plate precursor.
[0218]
<Thermosensitive layer coating solution composition>
Novolak resin (m-cresol / p-cresol = 60/40, weight average molecular weight 7,000, containing 0.5% by mass of unreacted cresol) 0.90 g
・ Ethyl methacrylate / isobutyl methacrylate / methacrylic acid copolymer (molar ratio 35/35/30) 0.10 g
-Cyanine dye A 0.1 g represented by the following structural formula
・ Tetrahydrophthalic anhydride 0.05g
・ 0.002 g of p-toluenesulfonic acid
-Ethyl violet counter ion with 6-hydroxy-β-naphthalenesulfonic acid 0.02 g
・ Fluorosurfactant (Defenser F-780F, manufactured by Dainippon Ink & Chemicals, Inc., solid content: 30% by mass) 0.0045 g (solid content conversion)
・ Fluorine-based surfactant (Defenser F-781F, manufactured by Dainippon Ink & Chemicals, Inc., solid content: 100% by mass) 0.035 g
・ Methyl ethyl ketone 12g
[0219]
[Chemical formula 2]

[0220]
6). Evaluation of planographic printing plate precursors
The printing durability, stain resistance, sensitivity, and ease of adjustment of the amount of water (shiny) of the lithographic printing plate were evaluated by the following methods.
(1) Printing durability
The resulting lithographic printing plate precursor was imaged using a TrendSetter manufactured by Creo at a drum rotation speed of 150 rpm and a beam intensity of 10 W.
Thereafter, using a PS processor 940H manufactured by Fuji Photo Film Co., Ltd., charged with an alkali developer having the following composition, the solution temperature was maintained at 30 ° C. and development was performed for 20 seconds to obtain a lithographic printing plate.
[0221]
<Alkali developer composition>
・ D-Sorbit 2.5% by mass
-Sodium hydroxide 0.85 mass%
・ Polyethylene glycol lauryl ether (weight average molecular weight 1,000)
0.5% by mass
・ Water 96.15% by mass
[0222]
The resulting lithographic printing plate was printed on a Lithrone printing machine manufactured by Komori Corporation using DIC-GEOS (N) black ink manufactured by Dainippon Ink & Chemicals, Inc. The printing durability was evaluated based on the number of printed sheets when visually recognized.
The results are shown in Table 2. In Table 2, the evaluation was as follows.
A: The number of printed sheets is 30,000 or more.
B: Number of printed sheets is less than 30,000 sheets, 20,000 sheets or more
C: Number of printed sheets is less than 20,000
[0223]
(2) Sensitivity
The lithographic printing plate precursor is output 500 mW, wavelength 830 nm, beam diameter 17 μm (1 / e²The main scanning speed is 5 m / sec and the plate surface energy amount is 140 mJ / cm, using a TrendSetter 3244 manufactured by CREO equipped with a semiconductor laser.²And imagewise exposure. For evaluation of sensitivity, the plate surface energy amount is 45 to 180 mJ / cm.²Up to 5mJ / cm²Samples subjected to exposure at different intervals were prepared.
The development processing was performed using an automatic processor PS900NP (Fuji Photo Film Co., Ltd.) filled with the developer B having the following composition under 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)). Sensitivity was defined as the minimum exposure amount at which an image could be formed after development processing from a sample in which the amount of plate surface energy was changed.
The results are shown in Table 1. In Table 2, the evaluation was as follows.
A: Energy amount (mJ / cm²), 100 mJ / cm²Is less than
B: Energy amount 150 mJ / cm²Less than 100mJ / cm²more than,
C: Energy amount 150 mJ / cm²more than.
[0224]
(3) Dirt resistance
Using the planographic printing plate obtained in the same manner as in the above (1) Evaluation of printing durability, printing was performed with DIC-GEOS (s) red ink on a Mitsubishi diamond F2 printer (manufactured by Mitsubishi Heavy Industries). The dirt on the blanket after printing 10,000 sheets was visually evaluated.
The results are shown in Table 2. In Table 2, the evaluation was as follows.
A: The blanket is almost clean
B: The blanket was a little dirty
BC: The blanket is dirty but within an acceptable range
C: The blanket is dirty and the printed material is clearly dirty
[0225]
(4) Shiny
(1) A lithographic printing plate obtained in the same manner as in the evaluation of printing durability is attached to a Lithlon printing machine manufactured by Komori Corporation, and the light condition of the non-image area of the printing plate is increased while increasing the amount of dampening water supplied. Was visually observed, and the shiny property (plate inspection property: ease of seeing water rising) was evaluated based on the supply amount of dampening water when it began to shine. The results are shown in Table 2.
In order from the one with a large amount of dampening water when it begins to shine to the one with a small amount,
Evaluation was carried out in five grades: A, AB, B, BC, and C.
[0226]
[Table 2]

[0227]
As is apparent from Table 2, all the lithographic printing plates using the lithographic printing plate support obtained by the method for producing a lithographic printing plate support of the present invention (Support Examples 1 to 4) were used. Excellent printing durability, stain resistance, sensitivity and shinyness.
Furthermore, Example 5 and Example 6 of the planographic printing plate precursor produced using the planographic printing plate supports 5 and 6 which were further subjected to mechanical roughening treatment using a brush and an abrasive after formation of the concavo-convex pattern. Are more uniform in surface quality than Examples 1 and 4 of the planographic printing plate precursors produced using the lithographic printing plate supports 1 and 2 which are not subjected to the mechanical surface roughening treatment, respectively. A good printing plate was obtained.
[0228]
【The invention's effect】
As described above, according to the present invention, a lithographic printing plate precursor that is excellent in all of the stain resistance, printing durability, sensitivity, and shiny when used as a lithographic printing plate and that satisfies industrial productivity as well. The lithographic printing plate support used is obtained.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of an apparatus for washing with a free-falling curtain-like liquid film used for washing with water in the method for producing 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 method for producing a lithographic printing plate support of the present invention.
FIG. 3 is a side view showing an example of a radial cell in an electrochemical surface roughening treatment using alternating current in the method for producing a lithographic printing plate support of the present invention.
FIG. 4 is a schematic view of an anodizing apparatus used for anodizing in the method for producing a lithographic printing plate support of the present invention.
FIG. 5 is a graph showing an example of a sine waveform diagram used for electrochemical surface roughening in the method for producing a lithographic printing plate support of the present invention.
FIG. 6 is a side view showing an example of an apparatus used for electrochemical surface roughening treatment using direct current in the method for producing a lithographic printing plate support of the present invention.
FIG. 7 is a side view showing another example of an apparatus used for electrochemical surface roughening treatment using direct current in the method for producing a lithographic printing plate support of the present invention.
[Explanation of symbols]
1 Aluminum plate
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 Main electrolytic cell
50 Auxiliary anode tank
61 Aluminum plate
62 Anode
63 Cathode
64 electrolyte
65 Electrolyzer
66 Supply nozzle
67 Drainage pipe
68 Supply pipe
100 Equipment for washing with a free-fall curtain-like liquid film
102 water
104 water storage tank
106 Water bottle
108 Rectifier
410 Anodizing equipment
412 Feeding tank
413 Intermediate tank
414 Anodizing tank
416 Aluminum plate
418, 426 electrolyte
420 anode
422, 428 pass rollers
424 Nip roller
430 cathode
434 DC power supply
436, 438 Liquid supply nozzle
440 Screening board
442 Drain outlet

Claims (5)

Composition: Fe: 0.3-1 mass%, Si: 0.15-1 mass%, Cu: 0.1-1 mass%, Mg: 0.1-1.5 mass%, Mn: 0.1 -1.5 mass%, Zn: 0.1-1.5 mass%, Cr: 0.01-0.1 mass%, Ti: 0.01-0.5 mass%, Al: 99.4-95 Aluminum plate that is mass%,
A method for producing a lithographic printing plate support, comprising roughening an aluminum plate having a concavo-convex pattern formed on a surface by transfer. A method for producing a support for a lithographic printing plate, comprising subjecting an aluminum plate having a concavo-convex pattern formed on a surface by transfer to a rough surface obtained from a bare metal in which used aluminum beverage cans have been dissolved (Used Beverage Can). The aluminum plate having the concavo-convex pattern formed on the surface by the transfer is manufactured by directly producing a thin plate by continuous casting, and cold rolling to adjust the final plate thickness in the annealing, cold rolling, and straightening processes, or the final plate The lithographic printing plate according to claim 1 or 2, which is an aluminum plate having a concavo-convex pattern formed on the surface of the aluminum plate by pressing and transferring the concavo-convex surface to the aluminum plate together with finish cold rolling to finish the surface shape after thickness adjustment. A method for producing a support. The roughening treatment is performed in order,
Etching treatment in alkaline solution,
Desmut treatment in acidic aqueous solution,
Electrochemical roughening treatment in aqueous solution containing nitric acid or hydrochloric acid,
Etching treatment in alkaline solution,
Desmut treatment in acidic aqueous solution,
Electrochemical roughening treatment in an aqueous solution containing hydrochloric acid,
Etching treatment in alkaline solution,
The method for producing a lithographic printing plate support according to any one of claims 1 to 3, wherein the desmutting treatment in an acidic aqueous solution and the anodizing treatment are performed. The method for producing a lithographic printing plate support according to claim 4, wherein a hydrophilization treatment is performed after the anodizing treatment.

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