JP2004053902A - Silver salt photothermographic dry imaging material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a silver salt photothermographic dry imaging material in which peeling of an imaging layer from the support is prevented and a failure in coating does not occur. <P>SOLUTION: The silver salt photothermographic dry imaging material is obtained by disposing at least one imaging layer comprising an organic silver salt, a photosensitive silver halide, a reducing agent and a binder on a support and has at least two non-imaging undercoat layers under the imaging layer, and the upper and lower undercoat layers comprise a hydrophobic resin and a water-soluble resin, respectively. <P>COPYRIGHT: (C)2004,JPO

Description

【００２５】
【化２】

【００２６】
本発明の銀塩光熱写真ドライイメージング材料に用いることができる支持体（以下、本発明に係る支持体という）の素材は、各種高分子材料、ガラス、ウール布、コットン布、紙、アルミニウム等の金属等が挙げられるが、可撓性のあるシート又はロールに加工できるものがよい。プラスチックフィルム（例えばセルロースアセテートフィルム、ポリエステルフィルム、ポリエチレンテレフタレートフィルム、ポリエチレンナフタレートフィルム、ポリアミドフィルム、ポリイミドフィルム、セルローストリアセテートフィルム又はポリカーボネートフィルム等）が用いられる。本発明の銀塩光熱写真ドライイメージング材料を医用として用いるには、本発明に係る支持体は、青色着色した２軸延伸熱固定した厚さ７０〜１８０μｍのポリエチレンテレフタレートフィルムが好ましい。又、特開２００１−２２０２６公報段落番号「００３０」〜「００３４」等に記載の技術を本発明に用いることができる。本発明に係る支持体は、コロナ放電処理をすることが好ましい。放電量の条件としては、５〜３０Ｗ／ｍ^２・分が好ましい。コロナ処理した支持体は、コロナ処理後１〜２ヶ月以内に本発明に係る下引層を塗布することが好ましい。
【００２７】
本発明に係る支持体は、プラズマ表面処理をすることができる。特に大気圧近傍でのプラズマ処理が好ましい。プラズマ放電を行う場合の処理用ガスとしては、アミノ基・カルボキシル基・水酸基・カルボニル基等の極性官能基を付与できるガスがよく、例えば窒素（Ｎ_２）ガス、水素（Ｈ_２）ガス、酸素（Ｏ_２）ガス・二酸化炭素（ＣＯ_２）ガス、アンモニア（ＮＨ_３）ガス、水蒸気等がある。また、反応ガス以外にもヘリウムやアルゴン等の不活性ガスが必要であり、ガスの混合比率も６０％以上にすることで安定な放電条件となる。しかし、パルス化された電界でプラズマを発生させる場合には、不活性ガスは必ずしも必要ではなく反応ガス濃度を増加させることが可能である。パルス電界の周波数１〜１００ｋＨｚの範囲が好ましい。１つのパルス電界が印加される時間は１〜１０００μｓであることが好ましく、電極に印加する電圧の大きさは電界強度が１〜１００ｋＶ／ｃｍとなる範囲が好ましい。
【００２８】
本発明の銀塩光熱写真ドライイメージング材料に用いることができる有機銀塩（以下、本発明に係る有機銀塩という）は還元可能な銀源であり、有機酸及びヘテロ有機酸の銀塩、特に長鎖の（炭素数１０〜３０、好ましくは１５〜２５）脂肪族カルボン酸及び含窒素複素環化合物の銀塩が好ましい。配位子が銀イオンに対する総安定度常数として４．０〜１０．０の値をもつようなリサーチ・ディスクロージャー１７０２９、２９９６３に記載された有機又は無機の錯体も好ましい。これら好適な銀塩の例としては、有機酸の銀塩、例えば、没食子酸、蓚酸、ベヘン酸、ステアリン酸、アラキジン酸、パルミチン酸、ラウリン酸等の銀塩等が挙げられる。その他の例としては、特開２００１−８３６５９公報段落番号「０１９３」に記載の有機銀塩が挙げられる。又、有機銀塩の作製法、有機銀塩の粒径、についても、同公報の段落番号「０１９４」〜「０１９７」の記載が参照できる。又本発明に係る有機銀塩として、特開２００１−４８９０２公報段落番号「００２８」〜段落番号「００３３」、特開２０００−７２７７７公報段落番号「００２５」〜段落番号「００４１」等に記載の技術を用いることができる。
【００２９】
本発明の銀塩光熱写真ドライイメージング材料に用いることができる感光性ハロゲン化銀（以下、本発明に係る感光性ハロゲン化銀という）とは、ハロゲン化銀結晶の固有の性質として本来的に、又は、人為的に物理化学的な方法により、可視光ないし赤外光を吸収し得て、かつ可視光ないし赤外光を吸収したときに当該ハロゲン化銀結晶内や結晶表面に物理化学的変化が起こり得るように処理調製されたハロゲン化銀結晶粒子をいう。
【００３０】
本発明に係る感光性ハロゲン化銀は、Ｐ．Ｇｌａｆｋｉｄｅｓ著Ｃｈｉｍｉｅｅｔ　Ｐｈｙｓｉｑｕｅ　Ｐｈｏｔｏｇｒａｐｈｉｑｕｅ（Ｐａｕｌ　Ｍｏｎｔｅｌ社刊、１９６７年）、Ｇ．Ｆ．Ｄｕｆｆｉｎ著　Ｐｈｏｔｏｇｒａｐｈｉｃ　Ｅｍｕｌｓｉｏｎ　Ｃｈｅｍｉｓｔｒｙ（Ｔｈｅ　Ｆｏｃａｌ　Ｐｒｅｓｓ刊、１９６６年）、Ｖ．Ｌ．Ｚｅｌｉｋｍａｎ　ｅｔ　ａｌ著Ｍａｋｉｎｇ　ａｎｄ　Ｃｏａｔｉｎｇ　Ｐｈｏｔｏｇｒａｐｈｉｃ　Ｅｍｕｌｓｉｏｎ（ＴｈｅＦｏｃａｌ　Ｐｒｅｓｓ刊、１９６４年）等に記載された方法を用いてハロゲン化銀粒子乳剤として調製することができる。この中でも、形成条件をコントロールしつつハロゲン化銀粒子を調製する所謂コントロールドダブルジェット法が好ましい。ハロゲン組成としては特に制限はなく、塩化銀、塩臭化銀、塩沃臭化銀、臭化銀、沃臭化銀、沃化銀のいずれであってもよい。又、本発明に係るハロゲン化銀の粒子形成は通常、ハロゲン化銀種粒子（核）生成と粒子成長の２段階に分けられ、一度にこれらを連続的に行う方法でもよく、又核（種粒子）形成と粒子成長を分離して行う方法でもよく、特開２００１−８３６５９公報段落番号「００６３」に記載の技術を用いることができる。
【００３１】
本発明に係る感光性ハロゲン化銀は、画像形成後の白濁を低く抑える、良好な画質を得る等のため平均粒子サイズが小さい方が好ましい。平均粒子サイズが０．２μｍ以下、より好ましくは０．０１μｍ〜０．１７μｍ、特に０．０２μｍ〜０．１４μｍが好ましい。ここでいう粒子サイズとは、ハロゲン化銀粒子が立方体或いは八面体のいわゆる正常晶である場合は、ハロゲン化銀粒子の稜の長さをいう。又、ハロゲン化銀粒子が平板状粒子である場合には主表面の投影面積と同面積の円像に換算したときの直径をいう。
【００３２】
粒子サイズは単分散であることが好ましく、詳しくは、特開２００１−８３６５９公報段落番号「００６４」〜段落番号「００６６」に記載の技術を用いることができる。粒子の形状としては、立方体、八面体、１４面体、平板状ハロゲン化銀粒子のいずれでもよい。平板状ハロゲン化銀粒子の場合、平均アスペクト比は、概ね１．５以上１００以下、好ましくは２以上５０以下がよい。これらは米国特許第５，２６４，３３７号、同第５，３１４，７９８号、同第５，３２０，９５８号等に記載の技術を適用できる。又、粒子形成技術としては、特開２００１−８３６５９公報段落番号「００６８」〜段落番号「００９０」に記載の技術を適用できる。
【００３３】
本発明に係る感光性ハロゲン化銀は、照度不軌改良のため元素周期律表の６族から１１族に属する遷移金属のイオンを含有することが好ましい。好ましい含有率は銀１モルに対し１×１０^−９〜１×１０^−２モル、より好ましくは１×１０^−８〜１×１０^−４の範囲である。好ましい遷移金属錯体又は錯体イオンは、一般式〔ＭＬ_６〕^ｍ（ここで、Ｍは元素周期表の６〜１１族の元素から選ばれる遷移金属、Ｌは配位子を表し、ｍは０、−、２−、３−又は４−を表す）で表される。Ｌで表される配位子の具体例としては、ハロゲンイオン（弗素イオン、塩素イオン等）、シアナイド、シアナート、チオシアナート、セレノシアナート、テルロシアナート、アジド及びアコの各配位子、ニトロシル、チオニトロシル等が挙げられ、好ましくはアコ、ニトロシル及びチオニトロシルである。アコ配位子が存在する場合には、配位子の一つ又は二つを占めることが好ましい。遷移金属配位錯イオンとしては、特開２００１−８３６５９公報段落番号「００９４」〜段落番号「００９５」記載のものを用いることができる。
【００３４】
本発明に係る感光性ハロゲン化銀は、化学増感されていることが好ましい。好ましい化学増感に関しては、特開２０００−１１２０５７公報段落番号「００４４」〜段落番号「００４５」に記載の化学増感剤、技術を用いることができる。
【００３５】
本発明に係る感光性ハロゲン化銀は、分光増感されていることが好ましい。好ましい分光増感に関しては、特開２００１−８３６５９公報段落番号「００９９」〜段落番号「０１４４」に記載の増感色素、技術を用いることができる。
【００３６】
本発明に係る感光性ハロゲン化銀は、増感色素とともに、それ自身分光増感作用をもたない色素あるいは可視光を実質的に吸収しない物質であって、強色増感効果を発現する強色増感剤を用いてもよい。強色増感剤については、特開２００１−８３６５９公報段落番号「０１４８」〜段落番号「０１５２」に記載の化合物を用いることができる。
【００３７】
本発明においては、上記の強色増感剤の他に、特開２００１−３３０９１８明細書段落番号「００２２」〜段落番号「００２８」に記載の一般式（１）で表される化合物と少なくとも１種のヘテロ原子を有する大環状化合物を強色増感剤として使用できる。該一般式（１）で表される化合物の具体例は、特開２００１−３３０９１８明細書段落番号「００３４」〜段落番号「００３９」に記載されている。又、ヘテロ原子を有する大環状化合物については、特開２００１−３３０９１８明細書段落番号「００４４」〜段落番号「００５４」に記載されている。
【００３８】
本発明の銀塩光熱写真ドライイメージング材料に用いることができる還元剤としては、銀塩光熱写真ドライイメージング材料の技術分野で公知の還元剤の中から適宜選択して使用することができる。特に、有機銀塩に脂肪族カルボン酸銀塩を使用する場合、２個以上のヒドロキシフェニル基がアルキレン基又は硫黄によって連結されたポリフェノール類、特にヒドロキシフェニル基のヒドロキシ置換位置に隣接した位置の少なくとも一つにアルキル基（例えばメチル基、エチル基、プロピル基、ｔ−ブチル基、シクロヘキシル基等）又はアシル基（例えばアセチル基、プロピオニル基等）が置換したヒドロキシフェニル基の２個以上がアルキレン基又は硫黄によって連結されたビスフェノール類が好ましい。
【００３９】
例えば、特開２０００−１１２０５７公報段落番号「００４７」〜段落番号「００４８」に記載のヒンダードフェノールタイプの還元剤は、本発明において好ましく用いられる。その具体的例示化合物については、特開２０００−１１２０５７公報段落番号「００５０」〜段落番号「００５１」に記載されている。還元剤の使用量は銀１モル当たり１×１０^−２〜１０モル、好ましくは１×１０^−２〜１．５モルである。
【００４０】
本発明の銀塩光熱写真ドライイメージング材料に用いることができるバインダー（以下、本発明に係るバインダーという）は、透明又は半透明で、一般に無色であり、天然高分子や合成高分子である。本発明に係るバインダーの例として、特開２００１−６６７２５公報段落番号「０１９３」に記載の天然又は合成高分子が挙げられる。本発明に係るバインダーとしては、ポリビニルアセタール類が好ましく、ポリビニルブチラールが特に好ましい。バインダーの使用量としては、バインダーと有機銀塩との割合は１５：１〜１：２、特に８：１〜１：１の範囲が好ましい。又、本発明に係るバインダーとしては、ポリマーラテックスも好ましく用いることができる。ポリマーラテックスに関しては、特開２００１−６６７２５公報段落番号「０１９４」〜段落番号「０２０３」に記載されている化合物と技術を適用できる。
【００４１】
本発明に係るバインダーは、架橋剤を用いることにより膜付きがよくなり、現像ムラが少なくなり、又、保存時のカブリ抑制や現像後のプリントアウト銀の生成を抑制する効果が期待できる。特開昭５０−９６２１６号公報に記載されているアルデヒド系、エポキシ系、エチレンイミン系、ビニルスルホン系、スルホン酸エステル系、アクリロイル系、カルボジイミド系、シラン化合物系の架橋剤を用いることができるが、好ましい架橋剤としてはイソシアネート系化合物、シラン化合物、エポキシ化合物又は酸無水物である。
【００４２】
イソシアネート系化合物については、特開２００１−８３６５９公報段落番号「０１５９」〜段落番号「０１６８」に記載されている化合物と技術を適用できる。エポキシ化合物については、特開２００１−８３６５９公報段落番号「０１７０」〜段落番号「０１８０」に記載されている化合物と技術を適用できる。酸無水物については、特開２００１−８３６５９公報段落番号「０１８２」〜段落番号「０１８７」に記載されている化合物と技術を適用できる。シラン化合物については、特開２００１−２６４９３０明細書段落番号「００２２」〜段落番号「００２８」に記載されている化合物と技術を適用できる。
【００４３】
本発明の銀塩光熱写真ドライイメージング材料は必要に応じて色調剤を用いることができる。本発明において用いることのできる色調剤としては、特開２０００−１９８７５７公報段落番号「００６４」〜段落番号「００６６」に記載されている化合物と技術を適用できる。
【００４４】
本発明の銀塩光熱写真ドライイメージング材料は、感光層を透過する光の量または波長分布を制御するために感光層と同じ側または反対の側にフィルター層を形成するか、感光層に染料又は顔料を含有させることが好ましい。本発明において用いられる染料としては、感光材料の感色性に応じて種々の波長領域の光を吸収する公知の化合物が使用できる。例えば、本発明の銀塩光熱写真ドライイメージング材料を赤外光による画像記録材料とする場合には、特開２００１−８３６５５明細書段落番号「００３２」〜段落番号「００３４」に開示されているようなチオピリリウム核を有するスクアリリウム染料、ピリリウム核を有するスクアリリウム染料等を用いることが好ましい。又、スクアリリウム染料に類似したチオピリリウム核を有するクロコニウム染料、ピリリウム核を有するクロコニウム染料を使用することもできる。
【００４５】
本発明の銀塩光熱写真ドライイメージング材料は、還元剤として、ビスフェノール類やスルホンアミドフェノール類のようなプロトンをもった還元剤が用いられているので、これらの水素を引き抜くことができる活性種を発生することにより還元剤を不活性化できる化合物が含有されていることが好ましい。無色の光酸化性物質として、露光時にフリーラジカルを反応活性種として生成可能な化合物が好ましい。これらの化合物として、特開２００１−２４９４２８明細書段落番号「００６５」〜段落番号「００６９」に開示されているビイミダゾリル化合物や、特開２００１−２４９４２８明細書段落番号「００７１」〜段落番号「００８２」に開示されているヨードニウム化合物を用いることができる。
【００４６】
本発明の銀塩光熱写真ドライイメージング材料は、還元剤を不活性化し還元剤が有機銀塩を銀に還元できないようにする化合物として、ハロゲン原子を活性種として放出する化合物を使用することができる。活性ハロゲン原子を生成する化合物の具体例としては、特開２００１−２４９４２８明細書段落番号「００８６」〜段落番号「０１０２」に開示されている化合物を用いることができる。
【００４７】
本発明の銀塩光熱写真ドライイメージング材料は省銀化剤を用いることができる。省銀化剤とは、一定の銀画像濃度を得るために必要な銀量を低減化し得る化合物をいう。この低減化する機能の作用機構は種々考えられるが、現像銀の被覆力を向上させる機能を有する化合物が好ましい。ここで、現像銀の被覆力とは、銀の単位量当たりの光学濃度をいう。本発明において用いることのできる省銀化剤としては、特開２００１−６６７２６明細書段落番号「００７５」〜段落番号「００８１」に開示されているヒドラジン誘導体化合物、特開２００１−６６７２６明細書段落番号「０１０９」〜段落番号「０１３２」に開示されているビニル化合物、特開２００１−６６７２６明細書段落番号「０１５０」〜段落番号「０１５８」に開示されている４級オニウム化合物が挙げられる。
【００４８】
本発明の銀塩光熱写真ドライイメージング材料は、本発明に係る下引層を設けた支持体上に有機銀塩、感光性ハロゲン化銀、還元剤、及びバインダーを含有する感光層を設けてなるものであるが、感光層の上に非感光層を形成するのが好ましい。例えば感光層の上には保護層が、感光層を保護する目的で、又支持体の反対の面にはくっつきを防止する為に、バッキング層が設けられるのが好ましい。これらの保護層やバッキング層に用いるバインダーとしては感光層よりもガラス転移点が高く、擦り傷や変形の生じにくいポリマー、例えばセルロースアセテート、セルロースアセテートブチレート等のポリマーが、前記のバインダーのなかから選ばれる。又、階調調整等のために、感光層を支持体の一方の側に２層以上又は支持体の両側に１層以上設置しても良い。
【００４９】
本発明の銀塩光熱写真ドライイメージング材料は、上述した各構成層の素材を溶媒に溶解又は分散させた塗布液を作り、それら塗布液を複数同時に重層塗布した後、加熱処理を行って形成されることが好ましい。ここで「複数同時に重層塗布」とは、各構成層（例えば感光層、保護層）の塗布液を作製し、これを支持体へ塗布する際に各層個別に塗布、乾燥の繰り返しをするのではなく、同時に重層塗布を行い乾燥する工程も同時に行える状態で各構成層を形成し得ることを意味する。即ち、下層中の全溶剤の残存量が例えば、７０質量％以下となる前に、上層を設けることが好ましい。
【００５０】
各構成層を複数同時に重層塗布する方法は特に制限はなく、例えばバーコーター法、カーテンコート法、浸漬法、エアーナイフ法、ホッパー塗布法、エクストルージョン塗布法などの公知の方法を用いることができる。これらのうちより好ましくはエクストルージョン塗布法と呼ばれる前計量タイプの塗布方式である。エクストルージョン塗布法はスライド塗布方式のようにスライド面での溶媒の揮発がないため、精密塗布、有機溶剤塗布に適している。この塗布方法は感光層を有する側について述べたが、バックコート層を設ける際、下引きとともに塗布する場合についても同様である。もちろん、本発明の銀塩光熱写真ドライイメージング材料は水系の溶媒でも良い。
【００５１】
本発明の銀塩光熱写真ドライイメージング材料の現像条件について説明する。現像条件は使用する機器、装置、或いは手段に依存して変化するが、典型的には適した高温に於いて像様に露光した光熱写真ドライイメージング材料を加熱することを伴う。露光後に得られた潜像は、例えば、約８０〜２００℃、好ましくは約１００〜２００℃で、概ね１秒〜２分間加熱することにより現像することができる。加熱温度が８０℃以下では短時間に十分な画像濃度が得られず、２００℃以上ではバインダーが溶融しローラーへの転写など、画像そのものだけでなく搬送性や、現像機等への悪影響を及ぼす。加熱することで有機銀塩（酸化剤として機能する）と還元剤との間の酸化還元反応により銀画像を生成する。
【００５２】
この反応過程は、外部からの水等の処理液の供給なしに進行する。加熱する機器、装置、或いは手段はホットプレート、アイロン、ホットローラー、炭素又は白色チタン等を用いた熱発生器として典型的な加熱手段で行ってよい。本発明の銀塩光熱写真ドライイメージング材料が保護層を有する場合であれば、保護層を有する側の面を加熱手段と接触させ加熱処理するのが、均一な加熱を行う上で、又熱効率、作業性の点などから好ましく、該面をヒートローラに接触させながら搬送し加熱処理して現像することが好ましい。
【００５３】
現像時において、本発明の銀塩光熱写真ドライイメージング材料は、溶剤を５〜１０００ｍｇ／ｍ^２、好ましくは１００〜５００ｍｇ／ｍ^２であるように調整する。これにより高感度、低かぶり、最高濃度の高い銀塩光熱写真ドライイメージング材料となる。
【００５４】
溶剤としては、アセトン、メチルエチルケトン、イソフォロン等のケトン類、メチルアルコール、エチルアルコール、イソプロピルアルコール、シクロヘキサノール、ベンジルアルコール等のアルコール類、エチレングリコール、ジエチレングリコール、トリエチレングリコール、プロピレングリコール、ヘキシレングリコール等のグリコール類、エチレングリコールモノメチルエーテル、ジエチレングリコールモノエチルエーテル等のエーテルアルコール類、イソプロピルエーテル等のエーテル類、酢酸エチル、酢酸ブチル等のエステル類、塩化メチレン、ジクロルベンゼン等の塩化物類、炭化水素類等が挙げられる。その他に水、ホルムアミド、ジメチルホルムアミド、トルイジン、テトラヒドロフラン、酢酸等が挙げられる。但しこれらに限定されるものではない。又、これらの溶剤は単独、又は、数種類組み合わせることができる。
【００５５】
なお、銀塩光熱写真ドライイメージング材料中の上記溶剤の含有量は塗布工程後の乾燥工程等における温度条件等の条件変化によって調整できる。又、当該溶剤の含有量は含有させた溶剤を検出するために適した条件下におけるガスクロマトグラフィーで測定できる。
【００５６】
本発明の銀塩光熱写真ドライイメージング材料の露光条件について説明する。本発明の銀塩光熱写真ドライイメージング材料の露光は、銀塩光熱写真ドライイメージング材料に付与した感色性に対し適切な光源を用いることが望ましい。例えば、赤外光に感じ得るものとした場合は、赤外光域ならばいかなる光源にも適用可能であるが、レーザーパワーがハイパワーであることや、本発明の銀塩光熱写真ドライイメージング材料を透明にできる等の点から、赤外半導体レーザー（７８０ｎｍ、８２０ｎｍ）が好ましく用いられる。
【００５７】
本発明の銀塩光熱写真ドライイメージング材料の露光は、レーザー走査露光により行うことが好ましく、その露光方法には種々の方法が採用できる。
【００５８】
第１の好ましい方法として、銀塩光熱写真ドライイメージング材料の露光面と走査レーザー光のなす角が実質的に垂直になることがないレーザー走査露光機を用いる方法が挙げられる。ここで、「実質的に垂直になることがない」とはレーザー走査中に最も垂直に近い角度として好ましくは５５度以上８８度以下、より好ましくは６０度以上８６度以下、更に好ましくは６５度以上８４度以下、最も好ましくは７０度以上８２度以下であることをいう。レーザー光が、感光材料に走査されるときの感光材料露光面でのビームスポット直径は、好ましくは２００μｍ以下、より好ましくは１００μｍ以下である。これは、スポット径が小さい方がレーザー入射角度の垂直からのずらし角度を減らせる点で好ましい。ビームスポット直径の下限は１０μｍである。このようなレーザー走査露光を行うことにより干渉縞様のムラの発生等のような反射光に係る画質劣化を減じることができる。
【００５９】
第２の方法として、縦マルチである走査レーザー光を発するレーザー走査露光機を用いて露光を行うことも好ましい。縦単一モードの走査レーザー光に比べて干渉縞様のムラの発生等の画質劣化が減少する。縦マルチ化するには、合波による戻り光を利用する、高周波重畳をかける、等の方法がよい。ここで、縦マルチとは、露光波長が単一でないことを意味し、通常露光波長の分布が５ｎｍ以上、好ましくは１０ｎｍ以上になるとよい。露光波長の分布の上限には特に制限はないが、通常６０ｎｍ程度である。
【００６０】
第３の態様として、２本以上のレーザを用いて、走査露光により画像を形成することも好ましい。複数本のレーザを利用した画像記録方法としては、高解像度化、高速化の要求から１回の走査で複数ラインずつ画像を書き込むレーザプリンタやデジタル複写機の画像書込み手段で使用されている技術であり、例えば特開昭６０−１６６９１６号公報等により知られている。これは、光源ユニットから放射されたレーザ光をポリゴンミラーで偏向走査し、ｆθレンズ等を介して感光体上に結像する方法であり、これはレーザイメージャなどと原理的に同じレーザ走査光学装置である。レーザプリンタやデジタル複写機の画像書込み手段における銀塩光熱写真ドライイメージング材料上へのレーザ光の結像は、１回の走査で複数ラインずつ画像を書き込むという用途から、一つのレーザ光の結像位置から１ライン分ずらして次のレーザ光が結像されている。具体的には、二つの光ビームは互いに副走査方向に像面上で数１０μｍオーダーの間隔で近接しており、印字密度が４００ｄｐｉ（ｄｐｉとは１インチ、即ち２．５４ｃｍ当たりのドット数を表す）で２ビームの副走査方向ピッチは６３．５μｍ、６００ｄｐｉで４２．３μｍである。
【００６１】
副走査方向に解像度分ずらした方法とは異なり、同一の場所に２本以上のレーザを入射角を変え露光面に集光させ画像形成することも好ましい。この際、通常の１本のレーザ（波長λ［ｎｍ］）で書き込むときの露光面での露光エネルギーがＥである場合、露光に使用するＮ本のレーザが同一波長（波長λ［ｎｍ］）、同一露光エネルギー（Ｅｎ）とした場合、０．９×Ｅ≦Ｅｎ×Ｎ≦１．１×Ｅの範囲にするのが好ましい。このようにすることにより、露光面ではエネルギーは確保されるが、それぞれのレーザ光の画像形成層への反射は、レーザの露光エネルギーが低いため低減され、ひいては干渉縞の発生が抑えられる。なお、上述では複数本のレーザの波長をλと同一のものを使用したが、波長の異なるものを用いても良い。この場合、λ［ｎｍ］に対して（λ−３０）＜λ１、λ２、・・・λｎ≦（λ＋３０）の範囲にするのが好ましい。
【００６２】
上述した第１、第２及び第３の態様の露光方法において、走査露光に用いるレーザとしては、一般によく知られている、ルビーレーザ、ＹＡＧレーザ、ガラスレーザ等の固体レーザ；Ｈｅ−Ｎｅレーザ、Ａｒイオンレーザ、Ｋｒイオンレーザ、ＣＯ_２レーザ、ＣＯレーザ、Ｈｅ−Ｃｄレーザ、Ｎ_２レーザ、エキシマーレーザ等のガスレーザ；ＩｎＧａＰレーザ、ＡｌＧａＡｓレーザ、ＧａＡｓＰレーザ、ＩｎＧａＡｓレーザ、ＩｎＡｓＰレーザ、ＣｄＳｎＰ_２レーザ、ＧａＳｂレーザ等の半導体レーザ；化学レーザ、色素レーザ等を用途に併せて適時選択して使用できるが、これらの中でもメンテナンスや光源の大きさの問題から、波長が６００〜１２００ｎｍの半導体レーザを用いるのが好ましい。
【００６３】
なお、レーザ・イメージャやレーザ・イメージセッタで使用されるレーザにおいて、銀塩光熱写真ドライイメージング材料に走査されるときの露光面でのビームスポット径は、一般に短軸径として５〜７５μｍ、長軸径として５〜１００μｍの範囲であり、レーザ光走査速度は銀塩光熱写真ドライイメージング材料固有のレーザ発振波長における感度とレーザパワーによって、銀塩光熱写真ドライイメージング材料毎に最適な値に設定することができる。
【００６４】
【実施例】
以下、実施例を挙げて本発明を詳細に説明するが、本発明はこれらに限定されない。
【００６５】
実施例１
〈下引加工した写真用支持体の作製〉
光学濃度０．１７０（コニカ株式会社製デンシトメータＰＤＡ−６５で測定）に青色着色した２軸延伸熱固定した厚さ１７５μｍのポリエチレンテレフタレートフィルムの両面に８Ｗ／ｍ^２・分のコロナ放電処理を施した写真用支持体に、下引加工を行った。すなわち、この写真用支持体の一方の面に、下引塗布液ａ−１を乾燥膜厚が０．２μｍになるように塗設し、１２３℃で乾燥して感光層側下引層を形成した（下引層Ａ−１という）。
【００６６】
また反対側の面にバッキング層下引層として下記下引塗布液ｂ−１を乾燥膜厚が０．２４μｍになるように塗設し、１２３℃で乾燥させてバッキング層側に帯電防止機能を持つ下引導電層（下引層Ｂ−１という）塗設した。
【００６７】
下引層Ａ−１とＢ−１の上表面に、８Ｗ／ｍ^２・分のコロナ放電を施し、下引層Ａ−１の上には、下記下引上層塗布液ａ−２を乾燥膜厚０．０５μｍになる様に塗設し１２３℃で乾燥させて下引上層Ａ−２とし、Ｂ−１の上には下記下引上層塗布液ｂ−２を乾燥膜厚０．３μｍになる様に塗設し１２３℃で乾燥させて下引上層Ｂ−２とし、さらに、１２３℃で２分間支持体を熱処理し、下引済み試料１−１を作製した。
【００６８】
感光層側下引層Ａ−１及びＡ−２を構成するバインダー疎水性樹脂と親水性樹脂を表１の様に変更した以外は、下引済み試料１−１の作製と同様にして下引済み試料１−２〜１−４を作製した。
【００６９】

【００７０】
《下引塗布液ｂ−１》
Ｆ−１（固形分８．３％）　　　　　　　　　　　　　　　　　　２２０ｇ
Ｌｘ−４（固形分３０％）　　　　　　　　　　　　　　　　　　　３８ｇ
ＰＶＡ−６１３（（株）クラレ製　ＰＶＡ）５質量％水溶液　　　０．４ｇ
界面活性剤（Ａ）　　　　　　　　　　　　　　　　　　　　　　０．５ｇ
以上に蒸留水を加えて１０００ｍｌとし、塗布液とした。
【００７１】
《下引上層塗布液ａ−２》
バインダー１（疎水性樹脂）　　　　　　　　　　　　　　　　表１記載量
バインダー２（親水性樹脂）　　　　　　　　　　　　　　　　表１記載量
界面活性剤（Ａ）　　　　　　　　　　　　　　　　　　　　　　０．４ｇ
真球状シリカマット剤　日本触媒　シーホスター　ＫＥ−Ｐ５０　０．３ｇ
以上に蒸留水を加えて１０００ｍｌとし、塗布液とした。
【００７２】
《下引上層塗布液ｂ−２》
変性水性ポリエステルＬｘ−３溶液（１８質量％）　　　　　　　２１５ｇ
真球状シリカマット剤　日本触媒　シーホスター　ＫＥ−Ｐ５０　０．３ｇ
界面活性剤（Ａ）　　　　　　　　　　　　　　　　　　　　　　０．４ｇ
以上に蒸留水を加えて１０００ｍｌとし、塗布液とした。
【００７３】
【化３】

【００７４】
使用した各化合物の詳細を以下に示す。
Ｆ−１：ＳｎＯ_２　特公昭３５−６６１６号記載の方法で加水分解後、デカンテーションを行ったもの（固形分８．３％）を使用した。
【００７５】
Ｌｘ−３：下記方法により合成したアクリル変性コポリエステル（固形分　１０％）
（水性ポリエステル溶液の調製）
テレフタル酸ジメチル３５．４質量部、イソフタル酸ジメチル３３．６３質量部、５−スルホイソフタル酸ジメチルナトリウム塩１７．９２質量部、エチレングリコール６２質量部、酢酸カルシウム一水塩０．０６５質量部、酢酸マンガン四水塩０．０２２質量部を、窒素気流下において、１７０〜２２０℃でメタノールを留去しながらエステル交換反応を行った後、リン酸トリメチル０．０４質量部、重縮合触媒として三酸化アンチモン０．０４質量部及び１，４−シクロヘキサンジカルボン酸６．８質量部を加え、２２０〜２３５℃の反応温度で、ほぼ理論量の水を留去しエステル化を行った。その後、更に反応系内を約１時間かけて減圧、昇温し最終的に２８０℃、１３３Ｐａ以下で約１時間重縮合を行い、水性ポリエステルＡ−１を作製した。得られた水性ポリエステルＡ−１の固有粘度は０．３３であった。
【００７６】
次いで、攪拌翼、環流冷却管、温度計を付した２Ｌの３つ口フラスコに、純水８５０ｍｌを入れ、攪拌翼を回転させながら、水性ポリエステルＡ−１を１５０ｇ徐々に添加した。室温でこのまま３０分間攪拌した後、１．５時間かけて内温が９８℃になるように加熱し、この温度で３時間加熱溶解した。加熱終了後、１時間かけて室温まで冷却し、一夜放置して、１５質量％の水性ポリエステル溶液を調製した。
【００７７】
（変性水性ポリエステルＬｘ−３溶液の調製）
攪拌翼、環流冷却管、温度計、滴下ロートを付した３Ｌの４つ口フラスコに、前記１５質量％の水性ポリエステル溶液１９００ｍｌを入れ、攪拌翼を回転させながら、内温度を８０℃まで加熱する。この中に、過酸化アンモニウムの２４％水溶液を６．５２ｍｌ加え、モノマー混合液（アクリル酸エチル３５．７ｇ、メタクリル酸メチル３５．７ｇ）を３０分間かけて滴下し、さらに３時間反応を続ける。その後３０℃以下まで冷却、濾過して、固形分濃度が１８質量％の変性水性ポリエステルＬｘ−３溶液を調製した。
【００７８】
Ｌｘ−４：アクリル系共重合ラテックス（固形分３０％）
▲１▼ブチルアクリレート（１０質量％）／ｔ−ブチルアクリレート（３５質量％）／スチレン（２７質量％）／２−ヒドロキシエチルアクリレート（２８質量％）の共重合体ラテックス液（固形分３０％）と
▲２▼ブチルアクリレート（４０質量％）／スチレン（３０質量％）／グリシジルメタクリレート（３０質量％）の共重合体ラテックス液（固形分３０％）のラテックス粒子１０％と９０％の混合物
〈バッキング層の形成〉
先に作製した下引済み試料１−１のバッキング下引層上に、下記のバッキング層塗布液を、乾燥膜厚が３．５μｍになるように押し出しコーターにて塗布、乾燥（乾燥温度１００℃、露点温度１０℃の乾燥風を用いて５分間かけて乾燥）し、バッキング層を形成した。
【００７９】
《バッキング層塗布液の調製》
メチルエチルケトン８３０ｇを攪拌しながら、セルロースアセテートブチレート（Ｅａｓｔｍａｎ　Ｃｈｅｍｉｃａｌ社、ＣＡＢ３８１−２０）８４．２ｇおよびポリエステル樹脂（Ｂｏｓｔｉｃ社、ＶｉｔｅｌＰＥ２２００Ｂ）４．５ｇを添加し、溶解した。次に、溶解した液に、０．３０ｇの赤外染料−１を添加し、さらにメタノール４３．２ｇに溶解したフッ素系界面活性剤（旭硝子社、サーフロンＫＨ４０）４．５ｇとフッ素系界面系活性剤（大日本インク社、メガファッグＦ１２０Ｋ）２．３ｇを添加して、溶解するまで十分に攪拌を行った。最後に、メチルエチルケトンに１質量％の濃度でディゾルバ型ホモジナイザにて分散したシリカ（Ｗ．Ｒ．Ｇｒａｃｅ社、シロイド６４Ｘ６０００）を７５ｇ添加、攪拌しバッキング層塗布液を調製した。
【００８０】
【化４】

【００８１】
〈感光層側の層形成〉
バッキング層を形成した前記写真用支持体の感光層側である下引上層Ａ−２面上に、下記感光層塗布液と表面保護層塗布液を押し出し（エクストルージョン）コーターを用いて同時に重層塗布することにより銀塩光熱写真ドライイメージング材料を作製した。塗布は、感光層は塗布銀量１．９ｇ／ｍ^２、表面保護層は乾燥膜厚で２．５μｍになる様にしておこなった。その後、乾燥温度７５℃、露点温度１０℃の乾燥風を用いて、１０分間乾燥を行い銀塩光熱写真ドライイメージング材料試料１−１を作製した。
【００８２】
（感光性ハロゲン化銀乳剤Ａの調製）
溶液（Ａ１）
フェニルカルバモイル化ゼラチン　　　　　　　　　　　　　　　８８．３ｇ
化合物（Ａ）（１０％メタノール水溶液）　　　　　　　　　　　　１０ｍｌ
臭化カリウム　　　　　　　　　　　　　　　　　　　　　　　　０．３２ｇ
水で５４２９ｍｌに仕上げる
溶液（Ｂ１）
０．６７ｍｏｌ／Ｌ硝酸銀水溶液　　　　　　　　　　　　　　２６３５ｍｌ
溶液（Ｃ１）
臭化カリウム　　　　　　　　　　　　　　　　　　　　　　　５１．５５ｇ
沃化カリウム　　　　　　　　　　　　　　　　　　　　　　　　１．４７ｇ
水で６６０ｍｌに仕上げる
溶液（Ｄ１）
臭化カリウム　　　　　　　　　　　　　　　　　　　　　　　１５４．９ｇ
沃化カリウム　　　　　　　　　　　　　　　　　　　　　　　　４．４１ｇ
塩化イリジウム（１％溶液）　　　　　　　　　　　　　　　　０．９３ｍｌ
水で１９８２ｍｌに仕上げる
溶液（Ｅ１）
０．４ｍｏｌ／Ｌ臭化カリウム水溶液　　　　　　　　　　下記銀電位制御量
溶液（Ｆ１）
水酸化カリウム　　　　　　　　　　　　　　　　　　　　　　　０．７１ｇ
水で２０ｍｌに仕上げる
溶液（Ｇ１）
５６％酢酸水溶液　　　　　　　　　　　　　　　　　　　　　１８．０ｍｌ
溶液（Ｈ１）
無水炭酸ナトリウム　　　　　　　　　　　　　　　　　　　　　１．７２ｇ
水で１５１ｍｌに仕上げる
化合物（Ａ）：
ＨＯ（ＣＨ_２ＣＨ_２Ｏ）ｎ−（ＣＨ（ＣＨ_３）ＣＨ_２Ｏ）_１７−（ＣＨ_２ＣＨ_２Ｏ）ｍＨ　（ｍ＋ｎ＝５〜７）
特公昭５８−５８２８８号公報に記載の混合攪拌機を用いて溶液（Ａ１）に溶液（Ｂ１）の１／４量及び溶液（Ｃ１）全量を温度４５℃、ｐＡｇ８．０９に制御しながら、同時混合法により４分４５秒を要して添加し核形成を行った。１分後、溶液（Ｆ１）の全量を添加した。この間ｐＡｇの調整を溶液（Ｅ１）を用いて適宜行った。６分間経過後、溶液（Ｂ１）の３／４量及び溶液（Ｄ１）の全量を、温度４５℃、ｐＡｇ８．０９に制御しながら、同時混合法により１４分１５秒かけて添加した。
【００８３】
５分間攪拌した後、４０℃に降温し、溶液（Ｇ１）を全量添加し、ハロゲン化銀乳剤を沈降させた。沈降部分２０００ｍｌを残して上澄み液を取り除き、水を１０リットル加え、攪拌後、再度ハロゲン化銀乳剤を沈降させた。沈降部分１５００ｍｌを残し、上澄み液を取り除き、更に水を１０リットル加え、攪拌後、ハロゲン化銀乳剤を沈降させた。沈降部分１５００ｍｌを残し、上澄み液を取り除いた後、溶液（Ｈ１）を加え、６０℃に昇温し、更に１２０分攪拌した。最後にｐＨが５．８になるように調整し、銀量１モル当たり１１６１ｇになるように水を添加し、感光性ハロゲン化銀乳剤Ａを得た。
【００８４】
この乳剤は、平均粒子サイズ０．０５８μｍ、粒子サイズの変動係数１２％、〔１００〕面比率９２％の単分散立方体沃臭化銀粒子であった。
【００８５】
（粉末有機銀塩Ａの調製）
４７２０ｍｌの純水にベヘン酸１３０．８ｇ、アラキジン酸６７．７ｇ、ステアリン酸４３．６ｇ、パルミチン酸２．３ｇを８０℃で溶解した。次に、１．５ｍｏｌ／Ｌの水酸化ナトリウム水溶液５４０．２ｍｌを添加し濃硝酸６．９ｍｌを加えた後、５５℃に冷却して脂肪酸ナトリウム溶液を得た。上記の脂肪酸ナトリウム溶液の温度を５５℃に保ったまま、４５．３ｇの上記の感光性ハロゲン化銀乳剤Ａと純水４５０ｍｌを添加し５分間攪拌した。
【００８６】
次に、１ｍｏｌ／Ｌの硝酸銀溶液７０２．６ｍｌを２分間かけて添加し、１０分間攪拌し有機銀塩分散物を得た。その後、得られた有機銀塩分散物を水洗容器に移し、脱イオン水を加えて攪拌後、静置させて有機銀塩分散物を浮上分離させ、下方の水溶性塩類を除去した。その後、排水の電導度が２μＳ／ｃｍになるまで脱イオン水による水洗、排水を繰り返し、遠心脱水を実施した後、得られたケーキ状の有機銀塩を、気流式乾燥機フラッシュジェットドライヤー（株式会社セイシン企業製）を用いて、窒素ガス雰囲気及び乾燥機入り口熱風温度の運転条件により含水率が０．１％になるまで乾燥して有機銀塩の乾燥済み粉末有機銀塩Ａを得た。
【００８７】
なお、有機銀塩組成物の含水率測定には赤外線水分計を使用した。
（予備分散液Ａの調製）
ポリビニルブチラール粉末（Ｍｏｎｓａｎｔｏ社製、Ｂｕｔｖａｒ　Ｂ−７９）１４．５７ｇをメチルエチルケトン１４５７ｇに溶解し、ＶＭＡ−ＧＥＴＺＭＡＮＮ社製ディゾルバＤＩＳＰＥＲＭＡＴ　ＣＡ−４０Ｍ型にて攪拌しながら粉末有機銀塩Ａ５００ｇを徐々に添加して十分に混合することにより予備分散液Ａを調製した。
【００８８】
（感光性乳剤分散液１の調製）
予備分散液Ａを、ポンプを用いてミル内滞留時間が１．５分間となるように、０．５ｍｍ径のジルコニアビーズ（東レ製トレセラム）を内容積の８０％充填したメディア型分散機ＤＩＳＰＥＲＭＡＴ　ＳＬ−Ｃ１２ＥＸ型（ＶＭＡ−ＧＥＴＺＭＡＮＮ社製）に供給し、ミル周速８ｍ／秒にて分散を行なうことにより感光性乳剤分散液１を調製した。
【００８９】
（安定剤液の調製）
１．０ｇの安定剤−１、０．３１ｇの酢酸カリウムをメタノール４．９７ｇに溶解し安定剤液を調製した。
【００９０】
（赤外増感色素液Ａの調製）
１９．２ｍｇの赤外増感色素ＳＤ−１、１．４８８ｇの２−クロロ−安息香酸、２．７７９ｇの安定剤−２および３６５ｍｇの５−メチル−２−メルカプトベンズイミダゾールを３１．３ｍｌのメチルエチルケトンに暗所にて溶解し赤外増感色素液Ａを調製した。
【００９１】
（添加液ａの調製）
現像剤としての１，１−ビス（２−ヒドロキシ−３，５−ジメチルフェニル）−２−メチルプロパンを２７．９８ｇと１．５４ｇの４−メチルフタル酸、０．４８ｇの前記赤外染料−１を１１０ｇのメチルエチルケトンに溶解し添加液ａとした。
【００９２】
（添加液ｂの調製）
１．５６ｇのカブリ防止剤−２、３．４３ｇのフタラジンを４０．９ｇのメチルエチルケトンに溶解し添加液ｂとした。
【００９３】
【化５】

【００９４】
《感光層塗布液の調製》
不活性気体雰囲気下（窒素９７％）において、前記感光性乳剤分散液１（５０ｇ）およびメチルエチルケトン１５．１１ｇを攪拌しながら２１℃に保温し、化学増感剤Ｓ−５（０．５％メタノール溶液）１０００μｌを加え、２分後にカブリ防止剤−１（１０％メタノール溶液）３９０μｌを加え、１時間攪拌した。さらに臭化カルシウム（１０％メタノール溶液）４９４μｌを添加して１０分撹拌した後、上記の有機化学増感剤の１／２０モル相当の金増感剤Ａｕ−５を添加、更に２０分攪拌した。続いて、安定剤液１６７ｍｌを添加して１０分間攪拌した後、１．３２ｇの前記赤外増感色素液Ａを添加して１時間攪拌した。
【００９５】
その後、温度を１３℃まで降温してさらに３０分攪拌した。１３℃に保温したまま、ポリビニルブチラール（Ｍｏｎｓａｎｔｏ社　Ｂｕｔｖａｒ　Ｂ−７９）１３．３１ｇを添加して３０分攪拌した後、テトラクロロフタル酸（９．４質量％メチルエチルケトン溶液）１．０８４ｇを添加して１５分間攪拌した。さらに攪拌を続けながら、１２．４３ｇの添加液ａ、１．６ｍｌのＤｅｓｍｏｄｕｒＮ３３００／モーベイ社製の脂肪族イソシアネート（１０％メチルエチルケトン溶液）、４．２７ｇの添加液ｂを順次添加し攪拌することにより感光層塗布液を得た。
【００９６】
【化６】

【００９７】
セルロースアセテートブチレート（Ｅａｓｔｍａｎ　Ｃｈｅｍｉｃａｌ社、７．５ｇのＣＡＢ１７１−１５）を４２．５ｇのメチルエチルケトンに溶解し、その中に、炭酸カルシウム（Ｓｐｅｃｉａｌｉｔｙ　Ｍｉｎｅｒａｌｓ社、Ｓｕｐｅｒ−Ｐｆｌｅｘ２００）５ｇを添加、ディゾルバ型ホモジナイザにて８０００ｒｐｍで３０分間分散しマット剤分散液を調製した。
【００９８】
《表面保護層塗布液の調製》
メチルエチルケトン８６５ｇを攪拌しながら、セルロースアセテートブチレート（Ｅａｓｔｍａｎ　Ｃｈｅｍｉｃａｌ社、ＣＡＢ１７１−１５）を９６ｇ、ポリメチルメタクリル酸（ローム＆ハース社、パラロイドＡ−２１）を４．５ｇ、ビニルスルホン化合物ＨＤ−１を１．５ｇ、ベンズトリアゾールを１．０ｇ、Ｆ系活性剤（旭硝子社、サーフロンＫＨ４０）を１．０ｇ、添加し溶解した。次に上記マット剤分散液３０ｇを添加して攪拌し、表面保護層塗布液を調製した。
【００９９】
ビニルスルホン化合物ＨＤ−１：（ＣＨ_２＝ＣＨＳＯ_２ＣＨ_２）_２ＣＨＯＨ
以上のように、下引済み試料１−１にバッキング層、感光層、表面保護層を設けて銀塩光熱写真ドライイメージング材料試料１−１を作製した。表１記載のように下引塗布液ａ−１及びａ−２のバインダー添加比率を変更した以外は同様に下引済み試料１−２〜１−４を作製し、銀塩光熱写真ドライイメージング材料試料１−１の作製と同様にして、銀塩光熱写真ドライイメージング材料試料１−１〜１−４を作製した。
【０１００】
評価法は次の通りである。
《ＥＣ面の塗布性評価》
作製した銀塩光熱写真ドライイメージング材料試料を濃度１．０になるように均一に露光し、ヒートドラムを有する熱現像用自動現像機を用いて、１２３℃で１５秒熱現像処理した。目視にて塗布性を評価した。
【０１０１】
１：塗布のムラがはっきりと判る
２：ムラが認められ診断上問題となる
３：ムラが認められるが診断上問題ない
４：殆どムラが判らない
５：均一でムラが無い。
【０１０２】
《現像後のＥＣ面の膜付評価》
ヒートドラムを有する熱現像用自動現像機を用いて、１２３℃で１５秒熱現像処理し、熱現像直後（１分以内）の試料に試料面に対して４５°の角度で、カミソリの刃を入れ、切り込みを挟んでセロファン粘着テープを圧着し、急激に４５°と反対方向にほぼ水平方向に引き剥がし熱現像画像形成層の剥離面積を求め、下記に示す評価基準に従って評価した。
【０１０３】
１．接着力は非常に弱く、熱現像画像形成層は完全に剥離する
２．剥離面積が５０％以上、１００％未満である
３．剥離面積が２０％以上、５０％未満である
４．接着力は強く、剥離面積は５％以上、２０％未満である
５．接着力は非常に強く、剥離面積は５％未満である。
【０１０４】
【表１】

【０１０５】
Ｌｘ−１：ブチルアクリレート（１０質量％）／ｔ−ブチルアクリレート（３５質量％）／スチレン（２７質量％）／２−ヒドロキシエチルアクリレート（２８質量％）の共重合体ラテックス液（固形分３０％）のラテックス粒子
Ｌｘ−２：ブチルアクリレート（４０質量％）／スチレン（３０質量％）／グリシジルメタクリレート（３０質量％）の共重合体ラテックス液（固形分３０％）のラテックス粒子１０％と９０％の混合物
ＰＶＡ３：ＰＶＡ−６１７　クラレ（株）の水分散物（固形分５％）：ケン化度９５
ＰＶＡ４：ＰＶＡ−２１７　クラレ（株）の水分散物（固形分５％）：ケン化度８８
表１から明らかなように、本発明の請求項１に該当する下引済み試料及び銀塩光熱写真ドライイメージング材料試料は、比較試料に比べて、支持体と、画像形成層の剥離の防止及び塗布故障の発生が改良されている。
【０１０６】
実施例２
表２で示すように下引塗布液ａ−１及びａ−２のバインダー添加比率を変更した以外は実施例１と同様にして、下引済み試料２−１〜２−９及び銀塩光熱写真ドライイメージング材料試料２−１〜２−９を作製した。
【０１０７】
【表２】

【０１０８】
ＰＶＡ５：ＰＶＡ−２０５　クラレ（株）の水分散物（固形分５％）：ケン化度８８
表２から明らかなように、本発明の請求項２に該当する下引済み試料及び銀塩光熱写真ドライイメージング材料試料は、比較試料に比べて、支持体と、画像形成層の剥離の防止及び塗布故障の発生が改良されている。
【０１０９】
実施例３
表３で示すように下引塗布液ａ−１及びａ−２のバインダー添加比率を変更した以外は実施例１と同様にして、下引済み試料３−１〜３−５及び銀塩光熱写真ドライイメージング材料試料３−１〜３−５を作製した。
【０１１０】
【表３】

【０１１１】
ＰＶＡ１：ＰＶＡ−１１７　クラレ（株）の水分散物（固形分５％）：ケン化度９８．５
ＰＶＡ２：ＰＶＡ−１０５　クラレ（株）の水分散物（固形分５％）：ケン化度９８．５
ＰＶＡ６：ＲＳ−２１１７　クラレ（株）の水分散物（固形分５％）：ケン化度９８
ＰＶＡ７：ＲＳ−２１０５　クラレ（株）の水分散物（固形分５％）：ケン化度９８
表３から明らかなように、本発明の請求項３に該当する下引済み試料及び銀塩光熱写真ドライイメージング材料試料は、比較試料に比べて、支持体と、画像形成層の剥離の防止及び塗布故障の発生が改良されている。
【０１１２】
実施例４
表４で示すように下引塗布液ａ−１及びａ−２のバインダー添加比率を変更した以外は実施例１と同様にして、下引済み試料４−１〜４−３及び銀塩光熱写真ドライイメージング材料試料４−１〜４−３を作製した。
【０１１３】
【表４】

【０１１４】
表４から明らかなように、本発明の請求項４に該当する下引済み試料及び銀塩光熱写真ドライイメージング材料試料は、比較試料に比べて、支持体と、画像形成層の剥離の防止及び塗布故障の発生が改良されている。
【０１１５】
実施例５
表５で示すように下引塗布液ａ−１及びａ−２のバインダー添加比率を変更し、添加剤を加えた以外は実施例１と同様にして、下引済み試料５−１〜５−４及び銀塩光熱写真ドライイメージング材料試料５−１〜５−４を作製した。
【０１１６】
【表５】

【０１１７】
【化７】

【０１１８】
表５から明らかなように、本発明の請求項５に該当する下引済み試料及び銀塩光熱写真ドライイメージング材料試料は、比較試料に比べて、支持体と、画像形成層の剥離の防止及び塗布故障の発生が改良されている。
【０１１９】
【発明の効果】
本発明により、支持体と、画像形成層の剥離の防止及び塗布故障の発生しない銀塩光熱写真ドライイメージング材料を提供することができた。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a silver salt photothermographic dry imaging material comprising a support provided with a photosensitive layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder. The present invention relates to a silver salt photothermographic dry imaging material characterized by a support having a formed undercoat layer.
[0002]
[Prior art]
Conventionally, in the fields of medical treatment and printing plate making, the waste liquid due to wet processing of image forming materials has been a problem in terms of workability.In recent years, the amount of treated waste liquid has been strongly reduced from the viewpoint of environmental conservation and space saving. Is desired. Therefore, there is a need for a technique relating to photothermographic materials for photographic technology, which enables efficient exposure with a laser imager or a laser imagesetter and can form a high-resolution and clear black image. Such techniques include, for example, U.S. Patent Nos. 3,152,904 and 3,487,075; As described in Morgan, "Dry Silver Photographic Materials" (Handbook of Imaging Materials, Marcel Dekker, Inc., p. 48, 1991), on a silver support as described above on an organic salt. And silver salt photothermographic dry imaging materials containing photosensitive silver halide grains and a reducing agent are known. Since this silver salt photothermographic dry imaging material does not use any solution-based processing chemicals, it is possible to provide the user with a system that is simpler and does not damage the environment.
[0003]
By the way, these silver salt photothermographic dry imaging materials usually use a photosensitive silver halide as an optical sensor on a support, an organic silver salt as a supply source of silver ions, and a built-in reducing agent, usually at 80 to 140 ° C. A photosensitive layer for forming an image by thermal development and a backing layer containing a dye for absorbing laser light are provided. These layers must be firmly adhered to the support not only before thermal development but also after thermal development. On the other hand, the processing of the image forming layer is becoming more efficient by high-speed coating as the production technology increases year by year, but coating failures, especially coating cissing, are serious failures that lead to misdiagnosis, and a stable and robust design is desired. I have. An undercoat layer is provided on the support for the purpose of improving the adhesion and coating properties.
[0004]
The design of a silver salt photothermographic dry imaging material requires special considerations for thermal development different from a photosensitive material developed with a conventional developer. In particular, at the time of heat development, compared with the processing using a conventional developing solution, heat of 80 to 140 ° C. is usually applied, so that an easy-adhesion design different from the conventional one is required, and stronger adhesion is desired.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to provide a silver salt photothermographic dry imaging material which prevents peeling of a support and an image forming layer and does not cause coating failure.
[0006]
[Means for Solving the Problems]
The above object of the present invention has been achieved by the following configurations.
[0007]
1. In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. A silver salt photothermographic dry imaging material comprising at least two undercoat layers that do not form a polymer, and wherein the upper and lower layers of the undercoat layer contain a hydrophobic resin and a water-soluble resin, respectively.
[0008]
2. In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. Having at least two undercoat layers that do not form, and the upper and lower layers of the undercoat layer each contain a hydrophobic resin and a water-soluble resin, and the volume ratio of the water-soluble resin in the upper layer of the undercoat layer is A silver salt photothermographic dry imaging material characterized by being higher in volume ratio of the water-soluble resin in the lower layer of the undercoat layer.
[0009]
3. In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. Having at least two undercoat layers that do not form a polymer, wherein the upper and lower layers of the undercoat layer each contain a hydrophobic resin and a water-soluble resin, and the water-soluble resin has a saponification degree of 97% or more. A silver salt photothermographic dry imaging material comprising an alcohol unit.
[0010]
4. In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. Having at least two undercoat layers that do not form, and the upper layer and the lower layer of the undercoat layer each contain a hydrophobic resin and a water-soluble resin, and the hydrophobic resin contained in the upper layer and the lower layer of the undercoat layer. A silver salt photothermographic dry imaging material, wherein the water-soluble resin has the same composition.
[0011]
5. In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. Having at least two undercoat layers that do not form the above, and the upper and lower layers of the undercoat layer each contain a hydrophobic resin and a water-soluble resin, and the lower layer of the undercoat layer contains an epoxy group-containing compound. A silver salt photothermographic dry imaging material characterized by the following.
[0012]
The present invention will be described in more detail. In the invention, the undercoat layer on which no image is formed (also referred to as a non-image formation undercoat layer) may have conductivity. Preferably, metal oxide fine particles which easily form nonstoichiometric compounds such as oxygen-deficient oxides, metal-excess oxides, metal-deficient oxides, and oxygen-excess oxides are exemplified. Among them, the most preferable metal oxides for the present invention are metal oxide fine particles that can be produced in various manners. As the metal oxide, a crystalline metal oxide is generally used, and ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, B ₂ O, MoO ₃ and the like are used. A composite oxide can be used. ZnO Among _these, TiO 2, SnO ₂ is preferred, as the composite oxide, Al relative to ZnO, an In like, for TiO _2, Nb, Ta, etc., Sb relative to SnO _2, Nb, halogen Those containing 0.01 to 30 mol% of different elements such as elements are preferable, and those containing 0.1 to 10 mol% are particularly preferable.
[0013]
The volume resistivity of these metal oxide fine particles is preferably 10 ⁷ Ω · cm or less, particularly preferably 10 ⁵ Ω · cm or less. It is preferable to use a compound having an oxygen vacancy in the crystal or a small amount of a different kind of atom serving as a so-called donor for the metal oxide because conductivity is improved. The method for producing such metal oxide fine particles is described in detail in, for example, JP-A-56-143430.
[0014]
Although such metal oxide fine particles have high conductivity, it is necessary to consider the particle diameter and the ratio of particle / binder to light scattering, etc., that haze is deteriorated, that it is difficult to disperse, It is more preferable to use an inorganic colloid existing in a colloidal form in water. The inorganic colloids are those defined in Kyoritsu Publisher chemical Encyclopedia, it is intended to include ¹⁰⁵ to ⁹ atoms in one particle. Depending on the element, it can be obtained as a metal colloid, oxide colloid, or hydroxide colloid. As the metal colloid, gold, palladium, platinum, silver, sulfur and the like are preferably used. As the oxide colloid, hydroxide colloid, carbonate colloid, and sulfate colloid, zinc, magnesium, silicon, calcium, aluminum, strontium Oxide colloids such as barium, zirconium, titanium, manganese, iron, cobalt, nickel, tin, indium, molybdenum and vanadium, hydroxide colloids, carbonate colloids and sulfate colloids are preferably used in the present invention. Particularly, ZnO, TiO ₂ and SnO ₂ are preferable, and SnO ₂ is particularly preferable. Examples of doping with hetero atoms include Al and In for ZnO, Nb and Ta for TiO ₂ , and Sb, Nb and halogen elements for SnO ₂ . . The average particle size of the inorganic colloid particles is preferably from 0.001 to 1 μm from the viewpoint of dispersion stability.
[0015]
With respect to the method for producing the metal oxide colloid used in the present invention, particularly the colloidal SnO ₂ sol composed of stannic oxide, a method in which ultrafine SnO ₂ particles are dispersed in a suitable solvent, or a method in which Sn Any method such as a method of producing a compound from a dispersion reaction in a solvent may be used.
[0016]
Regarding the method for producing SnO ₂ ultrafine particles, temperature conditions are particularly important, and a method involving heat treatment at a high temperature is not preferable because it causes growth of primary particles and a phenomenon that crystallinity is increased. In some cases, the reaction should be performed at a temperature of 300 ° C. or lower, preferably 200 ° C. or lower, more preferably 150 ° C. or lower. However, heating from 25 ° C. to 150 ° C. is a means that is suitably selected when dispersion in the binder is considered.
[0017]
A method for producing a Sn compound soluble in a solvent from a decomposition reaction in the solvent will be described below. Solvent-soluble Sn compounds include compounds containing oxo anions such as K ₂ SnO ₃ .3H ₂ O, water-soluble halides such as SnCl ₄ , (R) ′ ₂ Sn (R) ₂ , ( R) ₃ SnX, a compound having the structure of (R) ₂ Sn (X) ₂ (where R and R ′ represent an alkyl group and X represents a halogen atom or a monovalent organic group), for example, ( Examples include organometallic compounds such as CH ₃ ) ₃ SnCl. (Pyridine) and (C ₄ H ₉ ) ₂ Sn (O ₂ CC ₂ H ₅ ) _2, and oxo salts such as Sn (SO ₄ ) ₂ .2H ₂ O. it can. As a method for producing a SnO ₂ sol using a Sn compound soluble in these solvents, a physical method such as heating and pressurization, a chemical method such as oxidation, reduction, and hydrolysis after dissolving in the solvent, or There is a method of producing a SnO ₂ sol after passing through an intermediate. The method for producing a SnO ₂ sol described in JP-B-35-6616 can be applied to the metal oxide of the present invention.
[0018]
The hydrophobic resin used for the undercoat layer is preferably used as an aqueous dispersion (latex). Hydrophobic resins that can be preferably used in the present invention include styrene-butadiene copolymer, polyacrylic acid, polyacrylate and derivatives thereof, polyvinyl acetate, vinyl acetate-acrylate copolymer, polyolefin, olefin-acetic acid. Emulsions such as vinyl copolymers can also be used. In addition, organic semiconductors such as carbonate-based, polyester-based, urethane-based, epoxy-based resins, polyvinyl chloride, polyvinylidene chloride, and polypyrrole can also be used. These hydrophobic resins can be used as a mixture of two or more, but an acrylic copolymer is preferred.
[0019]
The acrylic copolymer preferably contains, for example, at least 20 mol% or more of alkyl acrylate and alkyl methacrylate. The copolymer component is preferably selected from styrene, styrene derivatives, olefin derivatives, halogenated ethylene derivatives, vinyl ester derivatives, acrylonitrile and the like.
[0020]
Examples of the hydrophilic resin used for the undercoat layer include proteins such as gelatin, derivative gelatin, colloidal albumin, and casein: cellulose compounds such as carboxymethylcellulose, hydroxyethylcellulose, diacetylcellulose, and triacetylcellulose; agar, sodium alginate, and starch derivatives. And many other synthetic resins such as synthetic hydrophilic colloids such as polyvinyl alcohol, poly-N-vinylpyrrolidone, polyacrylic acid copolymer, polyacrylamide or derivatives thereof, and partial hydrolysates. However, polyvinyl alcohol is particularly preferably used as the hydrophilic resin.
[0021]
Examples of the polymer containing a vinyl alcohol unit include derivatives of polyvinyl alcohol, such as ethylene copolymerized polyvinyl alcohol and a modified polyvinyl alcohol which is partially butyralized and dissolved in water.
[0022]
Polyvinyl alcohol preferably has a degree of polymerization of 100 or more. Examples of the polymer containing a vinyl alcohol unit include, as a copolymerization component of a vinyl acetate polymer before saponification, a vinyl compound such as ethylene and propylene, and acrylates (t-butyl acrylate, phenyl acrylate, 2-naphthyl). Acrylates), methacrylates (methyl methacrylate, ethyl methacrylate, 2-hydroxyethyl methacrylate, benzyl methacrylate, 2-hydroxypropyl methacrylate, phenyl methacrylate, cyclohexyl methacrylate, cresyl methacrylate, 4-chlorobenzyl methacrylate, ethylene glycol dimethacrylate) Acrylamides (acrylamide, methylacrylamide, ethylacrylamide, propylacrylamide, Acrylamide, tert-butylacrylamide, cyclohexylacrylamide, benzylacrylamide, hydroxymethylacrylamide, methoxyethylacrylamide, dimethylaminoethylacrylamide, phenylacrylamide, dimethylacrylamide, diethylacrylamide, β-cyanoethylacrylamide, diacetoneacrylamide, etc.), methacrylamides (Methacrylamide, methyl methacrylamide, ethyl methacrylamide, propyl methacrylamide, butyl methacrylamide, tert-butyl methacrylamide, cyclohexyl methacrylamide, benzyl methacrylamide, hydroxymethyl methacrylamide, methoxyethyl methacrylamide, dimethylaminoethyl methacrylamide , Phenylmethacrylamide, dimethylmethacrylamide, diethylmethacrylamide, β-cyanoethylmethacrylamide, etc.), styrenes (styrene, methylstyrene, dimethylstyrene, trimethylenestyrene, ethylstyrene, isopropylstyrene, chlorostyrene, methoxystyrene, acetoxystyrene) , Chlorostyrene, dichlorostyrene, bromostyrene, vinylbenzoic acid methyl ester, etc.), divinylbenzene, acrylonitrile, methacrylonitrile, N-vinylpyrrolidone, N-vinyloxazolidone, vinylidene chloride, phenylvinylketone, etc. Polymers may be mentioned. Of these, ethylene copolymerized polyvinyl alcohol is preferred.
[0023]
The epoxy group-containing compound that can be used in the present invention is not particularly limited as long as it has two or more epoxy groups in the molecule. For example, the following compounds may be mentioned. The amount to be used may be appropriately used depending on the kind of the intended light-sensitive material, and is not particularly limited, but is usually 0.1 to 20 vol%, preferably 0.2 to 5 vol% per binder. If the amount is too small, there is no effect, and if the amount is too large, the film sticking property deteriorates.
[0024]
Embedded image

[0025]
Embedded image

[0026]
The support (hereinafter referred to as the support according to the present invention) which can be used for the silver salt photothermographic dry imaging material of the present invention includes various polymer materials, glass, wool cloth, cotton cloth, paper, aluminum and the like. Metals and the like can be mentioned, but those which can be processed into flexible sheets or rolls are preferable. A plastic film (for example, a cellulose acetate film, a polyester film, a polyethylene terephthalate film, a polyethylene naphthalate film, a polyamide film, a polyimide film, a cellulose triacetate film, a polycarbonate film, or the like) is used. In order to use the silver salt photothermographic dry imaging material of the present invention for medical purposes, the support according to the present invention is preferably a blue-colored biaxially stretched and heat-fixed polyethylene terephthalate film having a thickness of 70 to 180 μm. In addition, techniques described in paragraph numbers “0030” to “0034” of JP-A-2001-22026 can be used in the present invention. The support according to the present invention is preferably subjected to a corona discharge treatment. The discharge amount is preferably set to 5 to 30 W / m ² · min. It is preferable to apply the undercoat layer according to the present invention to the support subjected to the corona treatment within 1 to 2 months after the corona treatment.
[0027]
The support according to the present invention can be subjected to a plasma surface treatment. In particular, plasma treatment near atmospheric pressure is preferable. As a processing gas in the case of performing plasma discharge, a gas to which a polar functional group such as an amino group, a carboxyl group, a hydroxyl group, or a carbonyl group can be provided is preferable. For example, nitrogen (N ₂ ) gas, hydrogen (H ₂ ) gas, oxygen There are (O ₂ ) gas / carbon dioxide (CO ₂ ) gas, ammonia (NH ₃ ) gas, water vapor and the like. In addition, an inert gas such as helium or argon is required in addition to the reaction gas, and a stable discharge condition can be obtained by setting the mixing ratio of the gas to 60% or more. However, when plasma is generated by a pulsed electric field, an inert gas is not always necessary, and it is possible to increase the reaction gas concentration. The frequency of the pulse electric field is preferably in the range of 1 to 100 kHz. The time during which one pulsed electric field is applied is preferably 1 to 1000 μs, and the magnitude of the voltage applied to the electrode is preferably in a range where the electric field intensity is 1 to 100 kV / cm.
[0028]
The organic silver salt that can be used in the silver salt photothermographic dry imaging material of the present invention (hereinafter, referred to as the organic silver salt of the present invention) is a reducible silver source, and silver salts of organic acids and hetero organic acids, particularly Silver salts of long-chain (10 to 30 carbon atoms, preferably 15 to 25 carbon atoms) aliphatic carboxylic acids and nitrogen-containing heterocyclic compounds are preferred. Organic or inorganic complexes described in Research Disclosure 17029, 29963 in which the ligand has a value of 4.0 to 10.0 as the total stability constant for silver ions are also preferable. Examples of these suitable silver salts include silver salts of organic acids, for example, silver salts of gallic acid, oxalic acid, behenic acid, stearic acid, arachidic acid, palmitic acid, lauric acid and the like. As another example, an organic silver salt described in Paragraph No. “0193” of JP-A-2001-83659 can be mentioned. The description of paragraphs “0194” to “0197” of the same publication can also be referred to for the preparation method of the organic silver salt and the particle size of the organic silver salt. Further, as the organic silver salt according to the present invention, techniques described in JP-A-2001-48902, paragraphs “0028” to “0033”, JP-A-2000-72777, paragraphs “0025” to “0041”, etc. Can be used.
[0029]
The photosensitive silver halide that can be used in the silver salt photothermographic dry imaging material of the present invention (hereinafter, referred to as the photosensitive silver halide according to the present invention) is essentially a unique property of silver halide crystals. Or, it can absorb visible light or infrared light by an artificial physicochemical method, and when the visible light or infrared light is absorbed, a physicochemical change occurs in the silver halide crystal or the crystal surface. Means silver halide crystal grains that have been processed and prepared so that the occurrence of silver halide can occur.
[0030]
The light-sensitive silver halide according to the present invention includes P.I. Chimieet Physique Photographique by Paul Glafkids (Paul Montel, 1967); F. Duffin, Photographic Emulsion Chemistry (published by The Focal Press, 1966); L. The emulsion can be prepared as a silver halide grain emulsion using a method described in Making and Coating Photographic Emulsion by Zelikman et al (published by The Focal Press, 1964). Of these, the so-called controlled double jet method for preparing silver halide grains while controlling the formation conditions is preferred. The halogen composition is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide, and silver iodide. The formation of silver halide grains according to the present invention is usually divided into two stages of silver halide seed grain (nucleus) generation and grain growth, and a method of continuously performing these at once may be used. A method may be used in which particle formation and particle growth are performed separately, and a technique described in paragraph number “0063” of JP-A-2001-83659 can be used.
[0031]
The photosensitive silver halide according to the present invention preferably has a small average grain size in order to suppress white turbidity after image formation and obtain good image quality. The average particle size is preferably 0.2 μm or less, more preferably 0.01 μm to 0.17 μm, and particularly preferably 0.02 μm to 0.14 μm. The term "grain size" as used herein refers to the length of a ridge of a silver halide grain when the silver halide grain is a cubic or octahedral so-called normal crystal. In the case where the silver halide grains are tabular grains, the diameter means a diameter when converted into a circular image having the same area as the projected area of the main surface.
[0032]
The particle size is preferably monodisperse, and more specifically, the technology described in paragraphs “0064” to “0066” of JP-A-2001-83659 can be used. The shape of the grains may be any of cubic, octahedral, tetradecahedral, and tabular silver halide grains. In the case of tabular silver halide grains, the average aspect ratio is generally from 1.5 to 100, preferably from 2 to 50. For these, techniques described in U.S. Patent Nos. 5,264,337, 5,314,798, and 5,320,958 can be applied. Further, as the particle forming technology, the technology described in paragraph numbers “0068” to “0090” of JP-A-2001-83659 can be applied.
[0033]
The photosensitive silver halide according to the present invention preferably contains ions of a transition metal belonging to Groups 6 to 11 of the periodic table of the element for improving illuminance failure. The preferred content is 1 × 10 ⁻⁹ to 1 × 10 ⁻² mol, more preferably 1 × 10 ⁻⁸ to 1 × 10 ⁻⁴ per mol of silver. A preferred transition metal complex or complex ion is represented by the general formula [ML ₆ ] ^m (where M is a transition metal selected from elements of Groups 6 to 11 of the periodic table, L represents a ligand, m is 0, -, 2-, 3- or 4-). Specific examples of the ligand represented by L include halogen ions (fluoride ion, chloride ion, etc.), cyanide, cyanate, thiocyanate, selenocyanate, tellurocyanate, azide and aquo ligands, nitrosyl, Thionitrosyl and the like are preferred, and preferably, aquo, nitrosyl and thionitrosyl. If an aquo ligand is present, it preferably occupies one or two of the ligands. As the transition metal coordination complex ion, those described in paragraph numbers “0094” to “0095” of JP-A-2001-83659 can be used.
[0034]
The photosensitive silver halide according to the present invention is preferably chemically sensitized. Regarding the preferred chemical sensitization, the chemical sensitizers and techniques described in paragraphs “0044” to “0045” of JP-A-2000-11205 can be used.
[0035]
The photosensitive silver halide according to the present invention is preferably spectrally sensitized. Regarding preferable spectral sensitization, sensitizing dyes and techniques described in Paragraph Nos. “0099” to “0144” of JP-A-2001-83659 can be used.
[0036]
The photosensitive silver halide according to the present invention, together with the sensitizing dye, is a dye that does not itself have a spectral sensitizing effect or a substance that does not substantially absorb visible light, and exhibits a supersensitizing effect. A color sensitizer may be used. As the supersensitizer, compounds described in paragraph numbers “0148” to “0152” of JP-A-2001-83659 can be used.
[0037]
In the present invention, in addition to the supersensitizer described above, at least one compound represented by the general formula (1) described in paragraphs “0022” to “0028” of JP-A-2001-330918 may be used. Macrocycles having different heteroatoms can be used as supersensitizers. Specific examples of the compound represented by the general formula (1) are described in paragraphs “0034” to “0039” of JP-A-2001-330918. The macrocyclic compound having a hetero atom is described in paragraphs “0044” to “0054” of JP-A-2001-330918.
[0038]
The reducing agent that can be used in the silver salt photothermographic dry imaging material of the present invention can be appropriately selected and used from known reducing agents in the technical field of silver salt photothermographic dry imaging materials. In particular, when an aliphatic silver salt of a carboxylic acid is used as the organic silver salt, at least two or more hydroxyphenyl groups at positions adjacent to the hydroxy-substituted positions of the polyphenols, particularly the hydroxyphenyl groups, which are linked by an alkylene group or sulfur, Two or more hydroxyphenyl groups substituted by an alkyl group (eg, methyl group, ethyl group, propyl group, t-butyl group, cyclohexyl group, etc.) or an acyl group (eg, acetyl group, propionyl group, etc.) are alkylene groups Or bisphenols linked by sulfur are preferred.
[0039]
For example, hindered phenol type reducing agents described in Paragraph Nos. “0047” to “0048” of JP-A-2000-112057 are preferably used in the present invention. Specific examples of the compounds are described in paragraphs “0050” to “0051” of JP-A-2000-11205. The amount of the reducing agent to be used is 1 × 10 ⁻² to 10 mol, preferably 1 × 10 ^{−2 to} 1.5 mol, per 1 mol of silver.
[0040]
The binder that can be used in the silver salt photothermographic dry imaging material of the present invention (hereinafter, referred to as the binder according to the present invention) is transparent or translucent, generally colorless, and is a natural polymer or a synthetic polymer. Examples of the binder according to the present invention include a natural or synthetic polymer described in paragraph No. “0193” of JP-A-2001-66725. As the binder according to the present invention, polyvinyl acetal is preferable, and polyvinyl butyral is particularly preferable. As for the amount of the binder used, the ratio of the binder to the organic silver salt is preferably 15: 1 to 1: 2, particularly preferably 8: 1 to 1: 1. Further, as the binder according to the present invention, a polymer latex can also be preferably used. As for the polymer latex, the compounds and techniques described in paragraphs “0194” to “0203” of JP-A-2001-66725 can be applied.
[0041]
By using a crosslinking agent, the binder according to the present invention can be expected to have an effect of improving film attachment, reducing development unevenness, and suppressing fog during storage and generation of printout silver after development. Aldehyde-based, epoxy-based, ethyleneimine-based, vinylsulfone-based, sulfonic ester-based, acryloyl-based, carbodiimide-based, and silane compound-based crosslinking agents described in JP-A-50-96216 can be used. Preferred crosslinking agents are isocyanate compounds, silane compounds, epoxy compounds or acid anhydrides.
[0042]
As for the isocyanate-based compound, the compounds and techniques described in paragraphs “0159” to “0168” of JP-A-2001-83659 can be applied. As for the epoxy compound, the compounds and techniques described in paragraphs “0170” to “0180” of JP-A-2001-83659 can be applied. As to the acid anhydride, the compounds and techniques described in paragraphs “0182” to “0187” of JP-A-2001-83659 can be applied. As for the silane compound, the compounds and techniques described in paragraphs “0022” to “0028” of JP-A-2001-264930 can be applied.
[0043]
In the silver salt photothermographic dry imaging material of the present invention, a toning agent can be used if necessary. As the toning agent that can be used in the present invention, the compounds and techniques described in paragraphs “0064” to “0066” of JP-A-2000-198757 can be applied.
[0044]
The silver salt photothermographic dry imaging material of the present invention may be formed with a filter layer on the same side or the opposite side as the photosensitive layer to control the amount or wavelength distribution of light transmitted through the photosensitive layer, or a dye or a dye on the photosensitive layer. It is preferable to include a pigment. As the dye used in the present invention, known compounds that absorb light in various wavelength regions according to the color sensitivity of the light-sensitive material can be used. For example, when the silver salt photothermographic dry imaging material of the present invention is used as an image recording material using infrared light, it is disclosed in paragraphs “0032” to “0034” of JP-A-2001-83655. It is preferable to use a squarylium dye having a thiopyrylium nucleus, a squarylium dye having a pyrylium nucleus, or the like. Further, a croconium dye having a thiopyrylium nucleus similar to a squarylium dye, and a croconium dye having a pyrylium nucleus can also be used.
[0045]
In the silver salt photothermographic dry imaging material of the present invention, since a reducing agent having a proton such as bisphenols or sulfonamidophenols is used as a reducing agent, active species capable of extracting these hydrogens are used. It is preferable that a compound capable of inactivating the reducing agent by generation is included. As the colorless photo-oxidizable substance, a compound capable of generating a free radical as a reactive species upon exposure is preferable. Examples of these compounds include biimidazolyl compounds disclosed in paragraphs “0065” to “0069” of JP-A-2001-249428 and paragraphs “0071” to “0082” of JP-A-2001-249428. Can be used.
[0046]
The silver salt photothermographic dry imaging material of the present invention can use a compound that releases a halogen atom as an active species as a compound that inactivates a reducing agent and prevents the reducing agent from reducing an organic silver salt to silver. . As specific examples of the compound that generates an active halogen atom, the compounds disclosed in paragraphs “0086” to “0102” of JP-A-2001-249428 can be used.
[0047]
The silver salt photothermographic dry imaging material of the present invention can use a silver saving agent. The silver saving agent is a compound capable of reducing the amount of silver required to obtain a certain silver image density. Although there are various possible mechanisms of the function of reducing the function, a compound having a function of improving the covering power of the developed silver is preferable. Here, the covering power of the developed silver means an optical density per unit amount of silver. Examples of the silver saving agent that can be used in the present invention include hydrazine derivative compounds disclosed in paragraphs “0075” to “0081” of JP-A-2001-66726, and paragraphs of JP-A-2001-66726. The vinyl compounds disclosed in “0109” to paragraph number “0132” and the quaternary onium compounds disclosed in paragraph numbers “0150” to “0158” of JP-A-2001-66726 are exemplified.
[0048]
The silver salt photothermographic dry imaging material of the present invention is obtained by providing a photosensitive layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support provided with an undercoat layer according to the present invention. However, it is preferable to form a non-photosensitive layer on the photosensitive layer. For example, a protective layer is preferably provided on the photosensitive layer, and a backing layer is provided for the purpose of protecting the photosensitive layer, and for preventing sticking to the opposite side of the support. As a binder used for the protective layer or the backing layer, a polymer having a higher glass transition point than the photosensitive layer and less likely to cause abrasion or deformation, for example, a polymer such as cellulose acetate or cellulose acetate butyrate, is selected from the above binders. It is. Further, for adjusting the gradation, two or more photosensitive layers may be provided on one side of the support or one or more layers may be provided on both sides of the support.
[0049]
The silver salt photothermographic dry imaging material of the present invention is formed by preparing a coating solution obtained by dissolving or dispersing the above-described constituent layer materials in a solvent, applying a plurality of these coating solutions simultaneously and then performing a heat treatment. Preferably. Here, “multi-layer coating at the same time” means that a coating solution for each constituent layer (for example, a photosensitive layer and a protective layer) is prepared, and when the coating solution is applied to a support, coating and drying are repeated for each layer individually. In other words, it means that each constituent layer can be formed in a state where the steps of simultaneously performing the multilayer coating and drying can be performed at the same time. That is, it is preferable to provide the upper layer before the remaining amount of all the solvents in the lower layer becomes, for example, 70% by mass or less.
[0050]
There is no particular limitation on the method of simultaneously coating a plurality of the constituent layers, and a known method such as a bar coater method, a curtain coat method, an immersion method, an air knife method, a hopper application method, and an extrusion application method can be used. . Of these, a pre-metering type coating method called an extrusion coating method is more preferable. The extrusion coating method is suitable for precision coating and organic solvent coating because the solvent does not volatilize on the slide surface unlike the slide coating method. Although this coating method has been described on the side having the photosensitive layer, the same applies to the case where the backcoat layer is provided and the coating is performed together with the undercoating. Of course, the silver salt photothermographic dry imaging material of the present invention may be an aqueous solvent.
[0051]
The development conditions of the silver salt photothermographic dry imaging material of the present invention will be described. Development conditions will vary depending on the equipment, equipment, or means used, but will typically involve heating the imagewise exposed photothermographic dry imaging material at a suitable elevated temperature. The latent image obtained after the exposure can be developed, for example, by heating at about 80 to 200 ° C, preferably about 100 to 200 ° C, for about 1 second to 2 minutes. If the heating temperature is 80 ° C. or lower, a sufficient image density cannot be obtained in a short time, and if the heating temperature is 200 ° C. or higher, the binder is melted and transferred to a roller, which adversely affects not only the image itself but also the transportability and the developing machine. . By heating, a silver image is generated by an oxidation-reduction reaction between an organic silver salt (functioning as an oxidizing agent) and a reducing agent.
[0052]
This reaction process proceeds without external supply of a processing liquid such as water. The equipment, apparatus or means for heating may be performed by a typical heating means such as a hot plate, an iron, a hot roller, a heat generator using carbon or white titanium or the like. If the silver salt photothermographic dry imaging material of the present invention has a protective layer, the heat treatment by contacting the surface having the protective layer with a heating means, in order to perform uniform heating, thermal efficiency, It is preferable from the viewpoint of workability and the like, and it is preferable that the surface is conveyed while being in contact with a heat roller, heated, and developed.
[0053]
During development, the silver salt photothermographic dry imaging material of the present invention, the solvent 5 to 1000 mg / ^{m 2,} preferably adjusted so that 100 to 500 mg / ^{m 2.} This results in a silver salt photothermographic dry imaging material with high sensitivity, low fog, and high maximum density.
[0054]
Examples of the solvent include ketones such as acetone, methyl ethyl ketone, and isophorone; alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, and benzyl alcohol; ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, and hexylene glycol. Glycols, ether alcohols such as ethylene glycol monomethyl ether and diethylene glycol monoethyl ether, ethers such as isopropyl ether, esters such as ethyl acetate and butyl acetate, chlorides such as methylene chloride and dichlorobenzene, and hydrocarbons And the like. Other examples include water, formamide, dimethylformamide, toluidine, tetrahydrofuran, acetic acid and the like. However, it is not limited to these. These solvents can be used alone or in combination of several kinds.
[0055]
The content of the solvent in the silver salt photothermographic dry imaging material can be adjusted by changing conditions such as temperature conditions in a drying step after the coating step. The content of the solvent can be measured by gas chromatography under conditions suitable for detecting the contained solvent.
[0056]
The exposure conditions of the silver salt photothermographic dry imaging material of the present invention will be described. In the exposure of the silver salt photothermographic dry imaging material of the present invention, it is desirable to use a light source appropriate for the color sensitivity imparted to the silver salt photothermographic dry imaging material. For example, if it is possible to feel infrared light, it can be applied to any light source in the infrared light range, but the laser power is high, and the silver salt photothermographic dry imaging material of the present invention is used. For example, an infrared semiconductor laser (780 nm, 820 nm) is preferably used from the viewpoint that the compound can be made transparent.
[0057]
Exposure of the silver salt photothermographic dry imaging material of the present invention is preferably performed by laser scanning exposure, and various exposure methods can be employed.
[0058]
As a first preferred method, there is a method using a laser scanning exposure machine in which the angle between the exposure surface of the silver salt photothermographic dry imaging material and the scanning laser beam does not become substantially perpendicular. Here, “being substantially not perpendicular” means that the angle is most perpendicular to the laser scanning, preferably 55 to 88 degrees, more preferably 60 to 86 degrees, and still more preferably 65 degrees. Not less than 84 degrees and most preferably not less than 70 degrees and not more than 82 degrees. The beam spot diameter on the exposed surface of the photosensitive material when the laser light is scanned on the photosensitive material is preferably 200 μm or less, more preferably 100 μm or less. This is preferable because the smaller the spot diameter is, the more the angle of deviation of the laser incident angle from the perpendicular can be reduced. The lower limit of the beam spot diameter is 10 μm. By performing such laser scanning exposure, it is possible to reduce image quality deterioration related to reflected light, such as occurrence of interference fringe-like unevenness.
[0059]
As a second method, it is also preferable to perform exposure using a laser scanning exposure device that emits a scanning laser beam that is a vertical multi. Image quality degradation such as generation of interference fringe-like unevenness is reduced as compared with the scanning laser beam in the longitudinal single mode. To achieve vertical multiplication, a method of using return light by multiplexing, superimposing high frequency, and the like are preferable. Here, the vertical multi means that the exposure wavelength is not single, and the distribution of the exposure wavelength is usually 5 nm or more, preferably 10 nm or more. The upper limit of the exposure wavelength distribution is not particularly limited, but is usually about 60 nm.
[0060]
As a third aspect, it is also preferable to form an image by scanning exposure using two or more lasers. As an image recording method using a plurality of lasers, there is a technique used in an image writing means of a laser printer or a digital copier which writes an image by a plurality of lines in one scan due to a demand for high resolution and high speed. And it is known, for example, from JP-A-60-166916. This is a method in which laser light emitted from a light source unit is deflected and scanned by a polygon mirror to form an image on a photoreceptor via an fθ lens or the like. It is. Image formation of laser light on silver halide photothermographic dry imaging materials in the image writing means of laser printers and digital copiers is performed by writing one laser light for the purpose of writing multiple lines of image in one scan. The next laser beam is imaged shifted by one line from the position. Specifically, the two light beams are close to each other at an interval of several tens of μm on the image plane in the sub-scanning direction, and the print density is 400 dpi (dpi is 1 inch, that is, the number of dots per 2.54 cm). ), The pitch in the sub-scanning direction of the two beams is 63.5 μm, and 42.3 μm at 600 dpi.
[0061]
Unlike the method in which the resolution is shifted by the resolution in the sub-scanning direction, it is also preferable to form an image by focusing two or more lasers at the same location on the exposure surface while changing the incident angle. At this time, if the exposure energy on the exposure surface when writing with one ordinary laser (wavelength λ [nm]) is E, the N lasers used for exposure have the same wavelength (wavelength λ [nm]). When the same exposure energy (En) is set, it is preferable to set the range of 0.9 × E ≦ En × N ≦ 1.1 × E. By doing so, energy is secured on the exposed surface, but the reflection of each laser beam to the image forming layer is reduced because the exposure energy of the laser is low, and thus the generation of interference fringes is suppressed. In the above description, a plurality of lasers have the same wavelength as λ, but lasers having different wavelengths may be used. In this case, it is preferable that (λ-30) <λ1, λ2,... Λn ≦ (λ + 30) with respect to λ [nm].
[0062]
In the above-described exposure methods of the first, second, and third aspects, as a laser used for scanning exposure, a well-known solid laser such as a ruby laser, a YAG laser, or a glass laser; a He-Ne laser; Gas lasers such as Ar ion laser, Kr ion laser, CO ₂ laser, CO laser, He-Cd laser, N ₂ laser, excimer laser; InGaP laser, AlGaAs laser, GaAsP laser, InGaAs laser, InAsP laser, CdSnP ₂ laser, GaSb A semiconductor laser such as a laser; a chemical laser, a dye laser, or the like can be appropriately selected and used in accordance with the intended use. Among them, a semiconductor laser having a wavelength of 600 to 1200 nm is preferably used due to maintenance and the size of a light source. preferable.
[0063]
In a laser used in a laser imager or a laser imagesetter, the beam spot diameter on the exposure surface when scanning a silver halide photothermographic dry imaging material is generally 5 to 75 μm as a short axis diameter, and a long axis diameter. The diameter is in the range of 5 to 100 μm, and the laser beam scanning speed is set to an optimum value for each silver halide photothermographic dry imaging material by the sensitivity and laser power at the laser oscillation wavelength inherent to the silver halide photothermographic dry imaging material. Can be.
[0064]
【Example】
Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto.
[0065]
Example 1
<Preparation of undercoated photographic support>
A corona discharge treatment of 8 W / m ² · min was applied to both sides of a 175 μm thick polyethylene terephthalate film which was biaxially stretched and heat-fixed to blue with an optical density of 0.170 (measured with a densitometer PDA-65 manufactured by Konica Corporation). An undercoat was applied to the photographic support. That is, an undercoating coating solution a-1 is applied on one surface of the photographic support so that the dry film thickness becomes 0.2 μm, and dried at 123 ° C. to form a photosensitive layer side undercoating layer. (Referred to as undercoat layer A-1).
[0066]
On the other side, an undercoat coating solution b-1 shown below was applied as a backing layer undercoat layer so that the dry film thickness became 0.24 μm, and dried at 123 ° C. to provide an antistatic function on the backing layer side. An undercoat conductive layer (undercoat layer B-1) was applied.
[0067]
A corona discharge of 8 W / m ² · min is applied to the upper surfaces of the undercoat layers A-1 and B-1. On the undercoat layer A-1, the following undercoat upper layer coating solution a-2 is dried. It is applied so as to have a thickness of 0.05 μm and dried at 123 ° C. to form an undercoating upper layer A-2. On B-1, the following undercoating upper layer coating solution b-2 has a dry film thickness of 0.3 μm. This was coated in the same manner and dried at 123 ° C. to form an undercoating upper layer B-2, and the support was heat-treated at 123 ° C. for 2 minutes to produce a subbed sample 1-1.
[0068]
Except that the binder hydrophobic resin and the hydrophilic resin constituting the photosensitive layer side undercoat layers A-1 and A-2 were changed as shown in Table 1, the undercoating was performed in the same manner as in the preparation of the undercoated sample 1-1. Finished samples 1-2 to 1-4 were produced.
[0069]

[0070]
<< Undercoat coating solution b-1 >>
220 g of F-1 (solid content: 8.3%)
Lx-4 (solid content 30%) 38g
PVA-613 (Kuraray Co., Ltd. PVA) 5 mass% aqueous solution 0.4 g
Surfactant (A) 0.5g
Distilled water was added to make 1000 ml as described above to obtain a coating solution.
[0071]
<< Lower layer upper layer coating liquid a-2 >>
Binder 1 (hydrophobic resin) Table 1 Content of Binder 2 (hydrophilic resin) Table 1 Content of Surfactant (A) 0.4 g
Spherical silica matting agent Nippon Shokubai Sea Hostar KE-P50 0.3g
Distilled water was added to make 1000 ml as described above to obtain a coating solution.
[0072]
<< Undercoat upper layer coating solution b-2 >>
215 g of modified aqueous polyester Lx-3 solution (18% by mass)
Spherical silica matting agent Nippon Shokubai Sea Hostar KE-P50 0.3g
Surfactant (A) 0.4g
Distilled water was added to make 1000 ml as described above to obtain a coating solution.
[0073]
Embedded image

[0074]
Details of each compound used are shown below.
F-1: SnO ₂ Hydrolyzed by the method described in JP-B-35-6616 and then decanted (solid content: 8.3%) was used.
[0075]
Lx-3: Acrylic-modified copolyester synthesized by the following method (solid content 10%)
(Preparation of aqueous polyester solution)
35.4 parts by mass of dimethyl terephthalate, 33.63 parts by mass of dimethyl isophthalate, 17.92 parts by mass of dimethyl sodium 5-sulfoisophthalate, 62 parts by mass of ethylene glycol, 0.065 parts by mass of calcium acetate monohydrate, acetic acid After subjecting 0.022 parts by mass of manganese tetrahydrate to transesterification while distilling off methanol at 170 to 220 ° C. under a nitrogen stream, 0.04 parts by mass of trimethyl phosphate and trioxide as a polycondensation catalyst were used. 0.04 parts by mass of antimony and 6.8 parts by mass of 1,4-cyclohexanedicarboxylic acid were added, and at a reaction temperature of 220 to 235 ° C., almost the theoretical amount of water was distilled off to carry out esterification. Thereafter, the pressure inside the reaction system was further reduced and the temperature was raised over about 1 hour, and finally polycondensation was performed at 280 ° C. and 133 Pa or lower for about 1 hour to produce an aqueous polyester A-1. The intrinsic viscosity of the obtained aqueous polyester A-1 was 0.33.
[0076]
Next, 850 ml of pure water was put into a 2 L three-necked flask equipped with a stirring blade, a reflux condenser and a thermometer, and 150 g of aqueous polyester A-1 was gradually added while rotating the stirring blade. After stirring at room temperature for 30 minutes, the mixture was heated to an internal temperature of 98 ° C. over 1.5 hours, and heated and dissolved at this temperature for 3 hours. After the completion of the heating, the mixture was cooled to room temperature over 1 hour, and left overnight to prepare a 15% by mass aqueous polyester solution.
[0077]
(Preparation of modified aqueous polyester Lx-3 solution)
Into a 3 L four-necked flask equipped with a stirring blade, a reflux condenser, a thermometer, and a dropping funnel, 1900 ml of the 15% by mass aqueous polyester solution is placed, and the inner temperature is heated to 80 ° C. while rotating the stirring blade. . 6.52 ml of a 24% aqueous solution of ammonium peroxide was added thereto, and a monomer mixture (ethyl acrylate 35.7 g, methyl methacrylate 35.7 g) was added dropwise over 30 minutes, and the reaction was continued for another 3 hours. Thereafter, the mixture was cooled to 30 ° C. or lower and filtered to prepare a modified aqueous polyester Lx-3 solution having a solid content of 18% by mass.
[0078]
Lx-4: Acrylic copolymer latex (solid content 30%)
(1) Copolymer latex liquid of butyl acrylate (10% by mass) / t-butyl acrylate (35% by mass) / styrene (27% by mass) / 2-hydroxyethyl acrylate (28% by mass) (solid content: 30%) And (2) a mixture of 10% and 90% latex particles of a copolymer latex liquid (solid content: 30%) of butyl acrylate (40% by mass) / styrene (30% by mass) / glycidyl methacrylate (30% by mass) Formation of layer>
The following backing layer coating solution was applied on the backing undercoat layer of the previously prepared undercoating sample 1-1 by an extrusion coater so that the dry film thickness was 3.5 μm, and dried (drying temperature: 100 ° C.) And drying using a drying air having a dew point of 10 ° C. for 5 minutes) to form a backing layer.
[0079]
<< Preparation of backing layer coating solution >>
While stirring 830 g of methyl ethyl ketone, 84.2 g of cellulose acetate butyrate (Eastman Chemical, CAB381-20) and 4.5 g of a polyester resin (Bostic, Vitel PE2200B) were added and dissolved. Next, 0.30 g of infrared dye-1 was added to the dissolved solution, and 4.5 g of a fluorinated surfactant (Surflon KH40, Asahi Glass Co., Ltd.) dissolved in 43.2 g of methanol was added thereto. 2.3 g of an agent (Dainippon Ink Co., Ltd., Megafag F120K) was added and sufficiently stirred until dissolved. Finally, 75 g of silica (WR Grace, Syloid 64X6000) dispersed in methyl ethyl ketone at a concentration of 1% by mass with a dissolver-type homogenizer was added and stirred to prepare a backing layer coating solution.
[0080]
Embedded image

[0081]
<Layer formation on photosensitive layer side>
The following photosensitive layer coating solution and surface protective layer coating solution were simultaneously coated on the undercoating upper layer A-2 surface, which is the photosensitive layer side of the photographic support having the backing layer formed thereon, using an extrusion (coating) coater. Thus, a silver salt photothermographic dry imaging material was prepared. The coating was carried out so that the photosensitive layer had a coating amount of 1.9 g / m ² and the surface protective layer had a dry film thickness of 2.5 μm. Thereafter, drying was performed for 10 minutes using a drying air having a drying temperature of 75 ° C. and a dew point temperature of 10 ° C. to prepare a silver salt photothermographic dry imaging material sample 1-1.
[0082]
(Preparation of photosensitive silver halide emulsion A)
Solution (A1)
88.3 g of phenylcarbamoylated gelatin
Compound (A) (10% aqueous methanol solution) 10 ml
Potassium bromide 0.32g
Solution to be finished to 5429 ml with water (B1)
0.67mol / L silver nitrate aqueous solution 2635ml
Solution (C1)
Potassium bromide 51.55 g
1.47 g of potassium iodide
Solution to be finished to 660 ml with water (D1)
Potassium bromide 154.9g
4.41 g of potassium iodide
0.93 ml of iridium chloride (1% solution)
Solution (E1) to make up to 1982 ml with water
0.4 mol / L aqueous solution of potassium bromide Solution of the following silver potential control amount (F1)
Potassium hydroxide 0.71g
Solution to be finished to 20 ml with water (G1)
56% acetic acid aqueous solution 18.0 ml
Solution (H1)
1.72 g of anhydrous sodium carbonate
Compound (A) which is made up to 151 ml with water:
_{HO (CH 2 CH 2 O)} n- (CH (CH 3) CH 2 O) 17 - (CH 2 CH 2 O) mH (m + n = 5~7)
Using a mixing stirrer described in JP-B-58-58288, a 1/4 amount of the solution (B1) and a total amount of the solution (C1) are simultaneously mixed with the solution (A1) while controlling the temperature to 45 ° C. and pAg 8.09. It took 4 minutes and 45 seconds to add and nucleate. One minute later, the entire amount of the solution (F1) was added. During this time, pAg was appropriately adjusted using the solution (E1). After a lapse of 6 minutes, the 量 amount of the solution (B1) and the entire amount of the solution (D1) were added over 14 minutes and 15 seconds by a double jet method while controlling the temperature at 45 ° C. and the pAg at 8.09.
[0083]
After stirring for 5 minutes, the temperature was lowered to 40 ° C., and the whole amount of the solution (G1) was added to precipitate a silver halide emulsion. The supernatant was removed except for the 2,000 ml sedimented portion, 10 liters of water was added, and after stirring, the silver halide emulsion was sedimented again. The supernatant was removed, leaving 1500 ml of the sedimented portion, and 10 liters of water was further added. After stirring, the silver halide emulsion was sedimented. After removing the supernatant liquid leaving 1500 ml of the sedimented portion, the solution (H1) was added, the temperature was raised to 60 ° C., and the mixture was further stirred for 120 minutes. Finally, the pH was adjusted to 5.8, and water was added so as to be 1161 g per 1 mol of silver, whereby photosensitive silver halide emulsion A was obtained.
[0084]
This emulsion was monodisperse cubic silver iodobromide grains having an average grain size of 0.058 μm, a grain size variation coefficient of 12%, and a [100] face ratio of 92%.
[0085]
(Preparation of powdered organic silver salt A)
130.8 g of behenic acid, 67.7 g of arachidic acid, 43.6 g of stearic acid and 2.3 g of palmitic acid were dissolved in 4720 ml of pure water at 80 ° C. Next, 540.2 ml of a 1.5 mol / L aqueous sodium hydroxide solution was added, 6.9 ml of concentrated nitric acid was added, and the mixture was cooled to 55 ° C. to obtain a fatty acid sodium solution. While maintaining the temperature of the above-mentioned sodium fatty acid solution at 55 ° C., 45.3 g of the above-mentioned photosensitive silver halide emulsion A and 450 ml of pure water were added and stirred for 5 minutes.
[0086]
Next, 702.6 ml of a 1 mol / L silver nitrate solution was added over 2 minutes and stirred for 10 minutes to obtain an organic silver salt dispersion. Thereafter, the obtained organic silver salt dispersion was transferred to a water washing container, deionized water was added thereto, and the mixture was stirred and allowed to stand. Then, the organic silver salt dispersion was floated and separated to remove lower water-soluble salts. After that, washing with deionized water and draining are repeated until the conductivity of the waste water becomes 2 μS / cm, and centrifugal dehydration is performed. (Manufactured by Seishin Enterprise Co., Ltd.) to dry the organic silver salt to obtain a dried organic silver salt A of organic silver salt under a nitrogen gas atmosphere and operating conditions of hot air temperature at the dryer inlet until the water content becomes 0.1%.
[0087]
An infrared moisture meter was used for measuring the water content of the organic silver salt composition.
(Preparation of Preliminary Dispersion A)
14.57 g of polyvinyl butyral powder (Butvar B-79, manufactured by Monsanto) is dissolved in 1457 g of methyl ethyl ketone, and 500 g of powdered organic silver salt A is gradually added while stirring with a dissolver DISPERMAT CA-40M manufactured by VMA-GETZMANN. A preliminary dispersion A was prepared by sufficiently mixing.
[0088]
(Preparation of photosensitive emulsion dispersion liquid 1)
The media type disperser DISPERMAT SL filled with 0.5% zirconia beads (Toray Torayceram) having a diameter of 0.5 mm so that the pre-dispersion liquid A is retained in the mill for 1.5 minutes using a pump. -C12EX type (manufactured by VMA-GETZMANN) and dispersed at a mill peripheral speed of 8 m / sec to prepare a photosensitive emulsion dispersion liquid 1.
[0089]
(Preparation of stabilizer liquid)
1.0 g of Stabilizer-1 and 0.31 g of potassium acetate were dissolved in 4.97 g of methanol to prepare a stabilizer solution.
[0090]
(Preparation of infrared sensitizing dye solution A)
19.2 mg of infrared sensitizing dye SD-1, 1.488 g of 2-chloro-benzoic acid, 2.779 g of stabilizer-2 and 365 mg of 5-methyl-2-mercaptobenzimidazole in 31.3 ml of methyl ethyl ketone Was dissolved in a dark place to prepare an infrared sensitizing dye solution A.
[0091]
(Preparation of additive liquid a)
27.98 g of 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -2-methylpropane as a developer, 1.54 g of 4-methylphthalic acid, and 0.48 g of the infrared dye-1 Was dissolved in 110 g of methyl ethyl ketone to obtain an additive liquid a.
[0092]
(Preparation of additive liquid b)
1.56 g of antifoggant-2 and 3.43 g of phthalazine were dissolved in 40.9 g of methyl ethyl ketone to obtain an additive liquid b.
[0093]
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[0094]
<< Preparation of photosensitive layer coating solution >>
In an inert gas atmosphere (nitrogen 97%), the photosensitive emulsion dispersion liquid 1 (50 g) and methyl ethyl ketone 15.11 g were kept at 21 ° C. while stirring, and the chemical sensitizer S-5 (0.5% methanol Solution) (1000 μl), and 2 minutes later, 390 μl of antifoggant-1 (10% methanol solution) was added, followed by stirring for 1 hour. Furthermore, after adding 494 μl of calcium bromide (10% methanol solution) and stirring for 10 minutes, a gold sensitizer Au-5 corresponding to 1/20 mol of the above-mentioned organic chemical sensitizer was added and further stirred for 20 minutes. . Then, after adding 167 ml of stabilizer liquids and stirring for 10 minutes, 1.32 g of the said infrared sensitizing dye liquid A was added and stirred for 1 hour.
[0095]
Thereafter, the temperature was lowered to 13 ° C., and the mixture was further stirred for 30 minutes. While keeping the temperature at 13 ° C, 13.31 g of polyvinyl butyral (Butvar B-79 from Monsanto) was added and stirred for 30 minutes, and 1.084 g of tetrachlorophthalic acid (9.4% by mass methyl ethyl ketone solution) was added. Stir for 15 minutes. Further, while stirring continuously, 12.43 g of additive solution a, 1.6 ml of Desmodur N3300 / Mobay's aliphatic isocyanate (10% methyl ethyl ketone solution), and 4.27 g of additive solution b were sequentially added and stirred, followed by exposure. A layer coating solution was obtained.
[0096]
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[0097]
Cellulose acetate butyrate (Eastman Chemical Company, 7.5 g of CAB171-15) was dissolved in 42.5 g of methyl ethyl ketone, into which 5 g of calcium carbonate (Specialty Minerals, Super-Pflex 200) was added, and the mixture was added to a dissolver-type homogenizer. And dispersed at 8000 rpm for 30 minutes to prepare a matting agent dispersion.
[0098]
<< Preparation of coating solution for surface protective layer >>
While stirring 865 g of methyl ethyl ketone, 96 g of cellulose acetate butyrate (Eastman Chemical Co., CAB171-15), 4.5 g of polymethyl methacrylic acid (Rohm & Haas Co., Paraloid A-21), and vinyl sulfone compound HD-1 were added. 1.5 g, benzotriazole (1.0 g) and F-based activator (Asahi Glass Co., Ltd., Surflon KH40) (1.0 g) were added and dissolved. Next, 30 g of the matting agent dispersion was added and stirred to prepare a coating solution for the surface protective layer.
[0099]
Vinyl sulfone compound HD-1: (CH ₂ ＣＨCHSO ₂ CH ₂ ) ₂ CHOH
As described above, a silver salt photothermographic dry imaging material sample 1-1 was prepared by providing the backing layer, the photosensitive layer, and the surface protective layer on the undercoated sample 1-1. Substrates 1-2 to 1-4 were prepared in the same manner except that the binder addition ratio of the subbing coating solutions a-1 and a-2 was changed as shown in Table 1, and a silver salt photothermographic dry imaging material was prepared. Silver salt photothermographic dry imaging material samples 1-1 to 1-4 were produced in the same manner as the production of sample 1-1.
[0100]
The evaluation method is as follows.
<< Evaluation of coatability of EC surface >>
The prepared silver salt photothermographic dry imaging material sample was uniformly exposed to a concentration of 1.0 and subjected to a heat development treatment at 123 ° C. for 15 seconds using an automatic developing machine having a heat drum. The applicability was evaluated visually.
[0101]
1: Unevenness of coating is clearly recognized 2: Unevenness is recognized and causes a problem in diagnosis 3: Non-uniformity is recognized but no problem occurs in diagnosis 4: Almost no unevenness is recognized 5: Uniformity and no unevenness
[0102]
<Evaluation of EC surface after development>
Using a heat developing automatic developing machine having a heat drum, heat-process at 123 ° C. for 15 seconds, and apply a razor blade to the sample immediately after heat development (within 1 minute) at an angle of 45 ° to the sample surface. The cellophane pressure-sensitive adhesive tape was press-fitted across the cuts and rapidly peeled off almost horizontally in a direction opposite to 45 ° to obtain a peeled area of the heat-developable image forming layer, which was evaluated according to the following evaluation criteria.
[0103]
1. 1. The adhesion is very weak, and the heat-developable image forming layer completely peels off. 2. The peeled area is 50% or more and less than 100%. 3. The peeled area is 20% or more and less than 50%. 4. The adhesive strength is strong, and the peeled area is 5% or more and less than 20%. The adhesion is very strong and the peel area is less than 5%.
[0104]
[Table 1]

[0105]
Lx-1: Copolymer latex liquid of butyl acrylate (10% by mass) / t-butyl acrylate (35% by mass) / styrene (27% by mass) / 2-hydroxyethyl acrylate (28% by mass) (solid content: 30% ) Latex particles Lx-2: 10% and 90% of latex particles of a copolymer latex liquid (solid content 30%) of butyl acrylate (40% by mass) / styrene (30% by mass) / glycidyl methacrylate (30% by mass) Of PVA3: PVA-617 Kuraray Co., Ltd. aqueous dispersion (solid content 5%): saponification degree 95
PVA4: PVA-217 Kuraray Co., Ltd. aqueous dispersion (solid content 5%): saponification degree 88
As is apparent from Table 1, the subbed sample and the silver salt photothermographic dry imaging material sample according to claim 1 of the present invention are more effective in preventing peeling of the support and the image forming layer than the comparative sample. The occurrence of coating failure has been improved.
[0106]
Example 2
As shown in Table 2, in the same manner as in Example 1 except that the binder addition ratio of the undercoating coating solutions a-1 and a-2 was changed, the undercoated samples 2-1 to 2-9 and the silver salt photothermogram Dry imaging material samples 2-1 to 2-9 were prepared.
[0107]
[Table 2]

[0108]
PVA5: PVA-205 Kuraray Co., Ltd. aqueous dispersion (solid content 5%): saponification degree 88
As is evident from Table 2, the undertreated sample and the silver salt photothermographic dry imaging material sample according to claim 2 of the present invention are more effective in preventing peeling of the support and the image forming layer than the comparative sample. The occurrence of coating failure has been improved.
[0109]
Example 3
As shown in Table 3, in the same manner as in Example 1 except that the binder addition ratio of the undercoating coating solutions a-1 and a-2 was changed, the undercoated samples 3-1 to 3-5 and the silver salt photothermogram were obtained. Dry imaging material samples 3-1 to 3-5 were produced.
[0110]
[Table 3]

[0111]
PVA1: PVA-117 Kuraray Co., Ltd. aqueous dispersion (solid content: 5%): saponification degree 98.5
PVA2: PVA-105 Kuraray Co., Ltd. aqueous dispersion (solid content 5%): saponification degree 98.5
PVA6: RS-2117 Kuraray Co., Ltd. aqueous dispersion (solid content 5%): saponification degree 98
PVA7: RS-2105 Kuraray Co., Ltd. aqueous dispersion (solid content 5%): saponification degree 98
As is clear from Table 3, the undertreated sample and the silver salt photothermographic dry imaging material sample according to the third aspect of the present invention can prevent separation of the support and the image forming layer from each other as compared with the comparative sample. The occurrence of coating failure has been improved.
[0112]
Example 4
As shown in Table 4, in the same manner as in Example 1 except that the binder addition ratio of the undercoating coating solutions a-1 and a-2 was changed, the undercoated samples 4-1 to 4-3 and the silver salt photothermogram Dry imaging material samples 4-1 to 4-3 were produced.
[0113]
[Table 4]

[0114]
As is evident from Table 4, the undertreated sample and the silver salt photothermographic dry imaging material sample according to claim 4 of the present invention were more effective in preventing peeling of the support and the image forming layer than the comparative sample. The occurrence of coating failure has been improved.
[0115]
Example 5
As shown in Table 5, the undercoated samples a-1 and a-2 were changed in the same manner as in Example 1 except that the binder addition ratio was changed and the additives were added. 4 and silver salt photothermographic dry imaging material samples 5-1 to 5-4 were prepared.
[0116]
[Table 5]

[0117]
Embedded image

[0118]
As is evident from Table 5, the undertreated sample and the silver salt photothermographic dry imaging material sample according to claim 5 of the present invention were more effective in preventing peeling of the support and the image forming layer than the comparative sample. The occurrence of coating failure has been improved.
[0119]
【The invention's effect】
According to the present invention, it was possible to provide a silver salt photothermographic dry imaging material in which peeling of the support and the image forming layer was prevented and coating failure did not occur.

Claims (5)

In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. A silver salt photothermographic dry imaging material comprising at least two undercoat layers that do not form a polymer, and wherein the upper and lower layers of the undercoat layer contain a hydrophobic resin and a water-soluble resin, respectively. In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. Having at least two undercoat layers that do not form, and the upper and lower layers of the undercoat layer each contain a hydrophobic resin and a water-soluble resin, and the volume ratio of the water-soluble resin in the upper layer of the undercoat layer is A silver salt photothermographic dry imaging material characterized by being higher in volume ratio of the water-soluble resin in the lower layer of the undercoat layer. In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. Having at least two undercoat layers that do not form a polymer, wherein the upper and lower layers of the undercoat layer each contain a hydrophobic resin and a water-soluble resin, and the water-soluble resin has a saponification degree of 97% or more. A silver salt photothermographic dry imaging material comprising an alcohol unit. In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. Having at least two undercoat layers that do not form, and the upper layer and the lower layer of the undercoat layer each contain a hydrophobic resin and a water-soluble resin, and the hydrophobic resin contained in the upper layer and the lower layer of the undercoat layer. A silver salt photothermographic dry imaging material, wherein the water-soluble resin has the same composition. In a silver salt photothermographic dry imaging material comprising at least one image forming layer containing an organic silver salt, a photosensitive silver halide, a reducing agent, and a binder on a support, an image is formed under the image forming layer. Having at least two undercoat layers that do not form the above, and the upper and lower layers of the undercoat layer each contain a hydrophobic resin and a water-soluble resin, and the lower layer of the undercoat layer contains an epoxy group-containing compound. A silver salt photothermographic dry imaging material characterized by the following.