JP4120222B2 - Silver halide photographic material for heat development - Google Patents

Description

【００１１】
【化６】

【００１２】
【化７】

【００１３】
【化８】

【００１４】
本発明における表面層とは、熱現像感光材料の乳剤層（感光層）側の実質的な表面を形成する層及びバッキング層側の実質的な表面を形成する層である。ここで「実質的な表面を形成する層」とは、膜厚が０．３μｍ以上の層であれば良く、同層の上に膜厚０．２μｍ以下のオーバーコート層があっても良い。
【００１５】
表面層のバインダーは、ポリビニルブチラール樹脂、セルロースアセテートブチレート等のメチルエチルケトン等の有機溶剤に溶解するポリマーであっても、スチレン−ブタヂエンラテックス等の水系溶媒に分散する各種のラテックスであっても良い。好ましくは、前者の有機溶剤に溶解するポリマーである。
【００１６】
一般式（１）〜（４）で示される化合物の表面層での使用量は特に限定されないが、表面層のバインダーを１００質量部とした場合３〜４０質量部が好ましい。
【００１７】
上記の化合物を表面層に添加することによる効果としては、熱現像直後のフィルムの捌き性を改善することを挙げることができる。その作用については不明であるが、フィルム表面のトライポロジー的な変化が起きているためと推定している。
【００１８】
以下に、熱現像感光材料の構成について説明する。
本発明の熱現像感光材料は、通常は支持体上に少なくとも１層の感光層及び該感光層に隣接する層を設けた少なくとも２層から構成され、又感光層の反対側には必要に応じて適宜バックコート層（ＢＣ層）、保護層等が設けられている。上記熱現像感光材料の感光層中には、分光増感色素で増感されてもよい感光性ハロゲン化銀粒子が含まれ、更に感光層又はその隣接層には銀源となる有機銀塩、銀塩を現像して銀画像を形成するための還元剤が含有される。熱現像感光材料の感光層やその隣接層には、熱現像の場を提供する高分子結合剤、親水性結合剤や疎水性結合剤、或いはラテックスが含有される。上記の熱現像感光材料において、必要によりイラジエーション防止又はハレーション防止のための染料を含有するＡＩ層又はＢＣ層が設けられる。又、上記の熱現像感光材料の感光層には、必要により銀画像の色調を整える色調剤を含有させることができる。
【００１９】
本発明において、有機銀塩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、特にこの中でも長鎖の（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の値を持つようなリサーチ・ディスクロージャー（以降、単にＲＤと略す）第１７０２９及び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以下のものが挙げられる。
【００２０】
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。銀のカルボキシアルキルチオ尿素塩、例えば、１−（３−カルボキシプロピル）チオ尿素、１−（３−カルボキシプロピル）−３，３−ジメチルチオ尿素等の銀塩、アルデヒドとヒドロキシ置換芳香族カルボン酸とのポリマー反応生成物の銀塩乃至錯体、例えば、アルデヒド類（ホルムアルデヒド、アセトアルデヒド、ブチルアルデヒド等）とヒドロキシ置換酸類（例えば、サリチル酸、安息香酸、３，５−ジヒドロキシ安息香酸）の反応生成物の銀塩乃至錯体、チオン類の銀塩又は錯体、例えば、３−（２−カルボキシエチル）−４−ヒドロキシメチル−４−チアゾリン−２−チオン、及び３−カルボキシメチル−４−チアゾリン−２−チオン等の銀塩乃至錯体、イミダゾール、ピラゾール、ウラゾール、１，２，４−チアゾール及び１Ｈ−テトラゾール、３−アミノ−５−ベンジルチオ−１，２，４−トリアゾール及びベンズトリアゾールから選択される窒素酸と銀との錯体又は塩、サッカリン、５−クロロサリチルアルドキシム等の銀塩、及びメルカプチド類の銀塩。これらの中、好ましい銀塩としてはベヘン酸銀、アラキジン酸銀及びステアリン酸銀が挙げられる。
【００２１】
本発明において用いることのできる感光性ハロゲン化銀粒子について説明する。尚、本発明における感光性ハロゲン化銀粒子とは、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、可視光乃至赤外光を吸収し得て、かつ可視光乃至赤外光を吸収したときに当該ハロゲン化銀結晶内及び／又は結晶表面において物理化学的変化が起こり得るように処理製造されたハロゲン化銀結晶粒子をいう。
【００２２】
本発明に用いられるハロゲン化銀粒子自体は、Ｐ．Ｇｌａｆｋｉｄｅｓ著Ｃｈｉｍｉｅ ｅｔ Ｐｈｙｓｉｑｕｅ Ｐｈｏｔｏｇｒａｐｈｉｑｕｅ（ＰａｕｌＭｏｎｔｅｌ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（Ｔｈｅ Ｆｏｃａｌ 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。即ち、酸性法、中性法、アンモニア法等のいずれでもよく、又可溶性銀塩と可溶性ハロゲン塩を反応させる形成としては、片側混合法、同時混合法、それらの組合せ等のいずれを用いてもよいが、上記方法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。
【００２３】
本発明で用いることのできるハロゲン化銀は、画像形成後の白濁を低く抑えるため、及び良好な画質を得るために平均粒子サイズが小さい方が好ましく、平均粒子サイズが０．２μｍ以下、より好ましくは０．０１〜０．１７μｍ、特に０．０２〜０．１４μｍ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には、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。
【００２４】
ハロゲン化銀粒子の形状としては立方体、八面体、１４面体粒子、平板状粒子、球状粒子、棒状粒子、ジャガイモ状粒子などを挙げることができるが、これらの中、特に、立方体、八面体、１４面体、平板状ハロゲン化銀粒子が好ましい。
【００２５】
平板状ハロゲン化銀粒子を用いる場合の平均アスペクト比は好ましくは１．５以上１００以下、より好ましくは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号等に記載されており、容易に目的の平板状粒子を得ることができる。更に、ハロゲン化銀粒子のコーナーが丸まった粒子も好ましく用いることができる。
【００２６】
本発明に用いられるハロゲン化銀粒子には、化学増感を施すことができる。例えば、特願平１２−０５７００４号及び特願平１２−０６１９４２号に開示されている方法等により、硫黄などのカルコゲンを放出する化合物や金イオンなどの貴金属イオンを放出する貴金属化合物で化学増感中心（化学増感核）を形成付与できる。本発明においては、カルコゲン原子を含有する有機増感剤により化学増感されているのが好ましい。これらカルコゲン原子を含有する有機増感剤はハロゲン化銀へ吸着可能な基と不安定カルコゲン原子部位を有する化合物であることが好ましい。
【００２７】
これらの有機増感剤としては、特開昭６０−１５００４６号、特開平４−１０９２４０号、特開平１１−２１８８７４号等の明細書に開示されている種々の構造を有する有機増感剤を用いることができるが、それらのうちカルコゲン原子が炭素原子又はリン原子と二重結合で結ばれている構造を有する化合物の少なくとも１種であることが好ましい。
【００２８】
又、上記の増感法の他、還元増感法等も用いることが出来、還元増感の貝体的な化合物としてはアスコルビン酸、２酸化チオ尿素、塩化第１スズ、ヒドラジン誘導体、ボラン化合物、シラン化合物、ポリアミン化合物等を用いることができる。又、乳剤のｐＨを７以上又はｐＡｇを８．３以下に保持して熟成することにより還元増感することができる。
【００２９】
本発明で用いることのできる感光性ハロゲン化銀粒子には、分光増感色素を吸着させ分光増感を施すことが好ましい。分光増感色素としてシアニン色素、メロシアニン色素、コンプレックスシアニン色素、コンプレックスメロシアニン色素、ホロポーラーシアニン色素、スチリル色素、ヘミシアニン色素、オキソノール色素、ヘミオキソノール色素等を用いることができる。例えば特開昭６３−１５９８４１号、同６０−１４０３３５号、同６３−２３１４３７号、同６３−２５９６５１号、同６３−３０４２４２号、同６３−１５２４５号、米国特許第４，６３９，４１４号、同第４，７４０，４５５号、同第４，７４１，９６６号、同第４，７５１，１７５号、同第４，８３５，０９６号に記載された増感色素が使用できる。本発明に使用される有用な増感色素は例えばＲＤ第１７６４３ IV−Ａ項（１９７８年１２月ｐ．２３）、同１８４３１ Ｘ項（１９７８年８月ｐ．４３７）に記載もしくは引用された文献に記載されている。特に各種レーザイメージャーやスキャナーの光源の分光特性に適した分光感度を有する増感色素を用いるのが好ましく、例えば、特開平９−３４０７８号、同９−５４４０９号、同９−８０６７９号記載の化合物が好ましく用いられる。
【００３０】
本発明の熱現像感光材料に用いられるハロゲン化銀粒子、或いは有機銀塩粒子を含有する乳剤は、増感色素とともに、それ自身分光増感作用を持たない色素或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物質を乳剤中に含ませ、これによりハロゲン化銀粒子が強色増感されていてもよい。有用な増感色素、強色増感を示す色素の組合せ及び強色増感を示す物質はＲＤ第１７６４３（１９７８年１２月発行）第２３頁 IVのＪ項、或いは特公平９−２５５００号、同４３−４９３３号、特開昭５９−１９０３２号、同５９−１９２２４２号、特開平５−３４１４３２号等に記載されているものを用いることができる。本発明においては、上記の強色増感剤の他に、特願平１２−０７０２９６号に開示されている一般式（１）で表される化合物と大環状化合物を強色増感剤として使用できる。
【００３１】
本発明においては省銀化剤を用いることが出来る。ここでいう省銀化剤とは、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。省銀化剤としては、ヒドラジン誘導体化合物、ビニル化合物、４級オニウム化合物等が好ましい例として挙げられる。
【００３２】
本発明に好適な還元剤の例は、米国特許第３，７７０，４４８号、同第３，７７３，５１２号、同第３，５９３，８６３号、及びＲＤ第１７０２９及び第２９９６３に記載されており、公知の還元剤の中から適宜選択して使用することが出来るが、有機銀塩に脂肪族カルボン酸銀塩を使用する場合には、２個以上のフェノー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、特にフェノー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）が置換したフェノール基の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。
【００３３】
このような還元剤としては、上述のように、主に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持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。好適には、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。
【００３４】
従ってこれらの機能を有する化合物であればいかなる化合物でもよいが、複数の原子からなる有機フリーラジカルが好ましい。かかる機能を有しかつ熱現像感光材料に格別の弊害を生じることのない化合物であればいかなる構造を持った化合物でもよい。
【００３５】
又、これらのフリーラジカルを発生する化合物としては発生するフリーラジカルに、これが還元剤と反応し不活性化するに充分な時間接触できる位の安定性を持たせるために炭素環式、又は複素環式の芳香族基を有するものが好ましい。
【００３６】
本発明においては、膜付きや、現像ムラのみならず、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のために、架橋剤を用いることがある。本発明で用いられる架橋剤としては、従来写真感光材料用として使用されている種々の架橋剤、例えば、特開昭５０−９６２１６号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、イソシアネート系化合物、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、シラン化合物系架橋剤が挙げられ、そのうち好ましいの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。
【００３７】
本発明に用いられる好適な色調剤の例は、ＲＤ第１７０２９号、米国特許第４，１２３，２８２号、同第３，９９４，７３２号、同第３，８４６，１３６号及び同第４，０２１，２４９号に開示されており、例えば、次のものがある。イミド類（例えば、スクシンイミド、フタルイミド、ナフタルイミド、Ｎ−ヒドロキシ−１，８−ナフタルイミド）；メルカプタン類（例えば、３−メルカプト−１，２，４−トリアゾール）；フタラジノン誘導体又はこれらの誘導体の金属塩（例えば、フタラジノン、４−（１−ナフチル）フタラジノン、６−クロロフタラジノン、５，７−ジメチルオキシフタラジノン、及び２，３−ジヒドロ−１，４−フタラジンジオン）；フタラジンとフタル酸類（例えば、フタル酸、４−メチルフタル酸、４−ニトロフタル酸及びテトラクロロフタル酸）の組み合わせ；フタラジンとマレイン酸無水物、及びフタル酸、２，３−ナフタレンジカルボン酸又はｏ−フェニレン酸誘導体及びその無水物（例えば、フタル酸、４−メチルフタル酸、４−ニトロフタル酸及びテトラクロロフタル酸無水物）から選択される少なくとも１つの化合物との組み合わせ等が挙げられる。特に好ましい色調剤としてはフタラジノン又はフタラジンとフタル酸類、フタル酸無水物類の組み合わせである。
【００３８】
本発明においては、熱現像感光材料の表面層（感光層側、又支持体をはさみ感光層の反対側に非感光層を設けた場合にも）に、現像前の取り扱いや熱現像後の画像の傷つき防止のためマット剤を含有することが好ましく、バインダーに対し、質量比で０．１〜３０％含有することが好ましい。本発明において用いられるマット剤の材質は、有機物及び無機物のいずれでもよい。例えば、無機物としては、スイス特許第３３０，１５８号等に記載のシリカ、仏国特許第１，２９６，９９５号等に記載のガラス粉、英国特許第１，１７３，１８１号等に記載のアルカリ土類金属又はカドミウム、亜鉛等の炭酸塩等をマット剤として用いることができる。有機物としては、米国特許第２，３２２，０３７号等に記載の澱粉、ベルギー特許第６２５，４５１号や英国特許第９８１，１９８号等に記載された澱粉誘導体、特公昭４４−３６４３号等に記載のポリビニルアルコール、スイス特許第３３０，１５８号等に記載のポリスチレン或いはポリメタアクリレート、米国特許第３，０７９，２５７号等に記載のポリアクリロニトリル、米国特許第３，０２２，１６９号等に記載されたポリカーボネートの様な有機マット剤を用いることができる。
【００３９】
本発明においては帯電性を改良するために、金属酸化物及び／又は導電性ポリマーなどの導電性化合物を構成層中に含ませることができる。これらはいずれの層に含有させてもよいが、好ましくは下引層、バッキング層、感光層と下引の間の層などに含まれる。本発明においては米国特許第５，２４４，７７３号カラム１４〜２０に記載された導電性化合物が好ましく用いられる。
【００４０】
本発明の熱現像感光材料においては、感光層を透過する光の量又は波長分布を制御するために感光層と同じ側又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。
【００４１】
本発明の熱現像感光材料に用いられる支持体としては、例えば、ポリエチレンテレフタレート、ポリカーボネート、ポリエチレン、ポリビニルアセタール、セルロースエステル、セルローストリアセテート、ニトロセルロース、ポリエチレンナフタレート等のプラスチックフイルム、ガラス、紙、アルミニウム板等の金属板などが用いられる。
【００４２】
本発明においては、熱現像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、本発明に係る光熱写真材料を赤外光による画像記録材料とする場合には、特願平１１−２５５５５７号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（チオピリリウムスクアリリウム染料）及びピリリウム核を有するスクアリリウム染料（ピリリウムスクアリリウム染料）、又スクアリリウム染料に類似したチオピリリウムクロコニウム染料、又はピリリウムクロコニウム染料を使用することが好ましい。
【００４３】
本発明の熱現像感光材料は、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、乾燥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うることを意味する。即ち、下層中の全溶剤の残存量が７０質量％以下となる前に、上層を設けることである。各構成層を複数同時に重層塗布する方法には特に制限はなく、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、エクストリュ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リュ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。該エクストリュ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。
【００４４】
本発明において、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、高温に於いて像様に露光した情報記録用フィルムを加熱現像することにより、情報定着せしめることが特徴である。露光後に得られた潜像は、中程度の高温（例えば、約８０〜２００℃、好ましくは約１００〜２００℃）で十分な時間（一般には約１秒〜約２分間）、熱現像感光材料を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、又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、現像機等へも悪影響を及ぼす。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。この反応過程は、外部からの水等の処理液の一切の供給なしに進行する。
【００４５】
本発明の熱現像感光材料の露光は、該感光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、該感光材料を赤外光に感じ得るものとした場合は、赤外光域ならば如何なる光源にも適用可能であるが、レーザパワーがハイパワーであることや、感光材料を透明にできる等の点から、赤外半導体レーザ（７８０ｎｍ、８２０ｎｍ）がより好ましく用いられる。
【００４６】
本発明において、露光はレーザ走査露光により行うことが好ましいが、その露光方法には種々の方法が採用できる。例えば、第１の好ましい方法として、感光材料の露光面と走査レーザ光のなす角が実質的に垂直になることがないレーザ走査露光機を用いる方法が挙げられる。
【００４７】
ここで、「実質的に垂直になることがない」とはレーザ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。
【００４８】
又、第２の方法として、本発明における露光は縦マルチである走査レーザ光を発するレーザ走査露光機を用いて行うことも好ましい。縦単一モードの走査レーザ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。
【００４９】
更に、第３の態様としては、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。
【００５０】
このような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層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。尚、上述した各画像記録方法において、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、ＣＯ₂レーザ、ＣＯレーザ、Ｈｅ−Ｃｄレーザ、Ｎ₂レーザ、エキシマーレーザ等の気体レーザ；ＩｎＧａＰレーザ、ＡｌＧａＡｓレーザ、ＧａＡｓＰレーザ、ＩｎＧａＡｓレーザ、ＩｎＡｓＰレーザ、ＣｄＳｎＰ₂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。尚、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、熱現像感光材料を走査するときの該材料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熱現像感光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、感光材料毎に最適な値に設定することができる。
【００５１】
【実施例】
以下に実施例を挙げて本発明を更に具体的に説明するが、本発明は、下記実施例のみに限定されるものではない。
【００５２】
実施例１
〈熱現像用ハロゲン化銀写真感光材料の作製〉
厚さ１７５μｍで青色濃度０．１７５に着色された、２軸延伸ポリエチレンテレフタレートフィルム上に１２Ｗ／ｍ²・分の出力となるようにコロナ放電を施した後、下記下引塗布液１を乾燥膜厚が０．９μｍとなるように塗布し、１４０℃（露点温度：１２℃）の乾燥風で１０秒間かけて乾燥させ、下引層１を形成した。
（下引塗布液１）
純水 ９１１ｍｌ
化合物−１の３０％水溶液 ７３．０ｍｌ
トラックスＨ−４５ ５．７８ｍｌ
（日本油脂（株）製アニオン界面活性剤：固形分２％に調整）
アンモニア水（有効成分０．５％） ９．９ｍｌ
硬膜剤（Ｃ−６：有効成分２０％） ２．０２ｍｌ
次いで、上記下引層１に７Ｗ／ｍ²・分の出力となるようにコロナ放電を施した後、その上に下記下引塗布液２を、乾燥膜厚が０．９μｍとなるよう塗布した後、１４０℃（露点温度：１２℃）の乾燥風で１０秒間掛けて乾燥させて下引層２を形成し、次いで、１２３℃の乾燥ゾーンを２分間かけて搬送して、絶縁体粒子を含有する下引層２を設けた。
【００５３】
【化９】

【００５４】
（下引塗布液２）
純水 ９０５ｍｌ
化合物−２の３０％水溶液 ５９．２９ｍｌ
トラックスＨ−４５ ５．７８ｍｌ
（日本油脂（株）製アニオン界面活性剤：固形分２％に調整）
絶縁体粒子：サイリシア３５０（富士シリシア化学製）を超音波分散した溶液
（固形分濃度１％） ３３．５６ｍｌ
【００５５】
【化１０】

【００５６】
上記下引塗布液２は、下記の条件にて超音波分散を行った後、塗布に使用した。
【００５７】
分散条件：周波数＝２５ｋＨｚ、出力＝１００Ｗ、振動子外形寸法＝６４φ×３００ｍｍ、分散時間＝２０分
次いで、上記下引層２とは、プラスチックフィルムを挟んで反対側に、バック層面側の下引加工を、上記と同様の方法で行った。
【００５８】
上記作製したプラスチックフィルムの試料を用いて、以下に示す方法で調製した各構成層を順次塗布した。
（バック面側の塗布）
メチルエチルケトン（ＭＥＫ）８３０ｇを攪拌しながら、セルロースアセテートブチレート（ＥａｓｔｍａｎＣｈｅｍｉｃａｌ社、ＣＡＢ３８１−２０）８４．２ｇ及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、更にメタノール７０ｇ中に例示化合物１−３を８．４ｇ含有した溶液を添加して十分に攪拌を行った。最後に、ＭＥＫ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添加し攪拌してバック面側の塗布液を調製した。
【００５９】
【化１１】

【００６０】
このように調製したバック面塗布液を、前記作製した各プラスチックフィルムの下引層２上に、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、乾燥を行った。乾燥温度１００℃、露点温度１０℃の乾燥風を用いて５分間かけて乾燥した。
（感光層面側の塗布）
〔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（ＣＨ₂ＣＨ₂Ｏ）_n−（ＣＨ（ＣＨ₃）ＣＨ₂Ｏ）₁₇−（ＣＨ₂ＣＨ₂Ｏ）_mＨ
（ｍ＋ｎ＝５〜７）
特公昭５８−５８２８８号に示される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の全量を温度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。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１０Ｌ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１０Ｌ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。
【００６１】
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。
〔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１．５モル／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。
【００６２】
次に１モル／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。尚、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。
〔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（株）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／ｓ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。
〔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。
〔赤外増感色素液Ａの調製〕
１９．２ｍｇの赤外増感色素１、１．４８８ｇの２−クロロ−安息香酸、２．７７９ｇの安定剤−２及び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ＭＥＫに暗所にて溶解し赤外増感色素液Ａを調製した。
【００６３】
【化１２】

【００６４】
〔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ＭＥＫ１１０ｇに溶解し添加液ａとした。
〔添加液ｂの調製〕
３．５６ｇのカブリ防止剤−２、３．４３ｇのフタラジンをＭＥＫ４０．９ｇに溶解し添加液ｂとした。
【００６５】
【化１３】

【００６６】
〔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）及びＭＥＫ１５．１１ｇ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。更に臭化カルシウム（１０％メタノール溶液）４９４μｌを添加して１０分撹拌した後に上記の化学増感剤Ｓ−５の１／２０モル相当の金増感剤Ａｕ−５を添加し、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。その後、温度を１３℃まで降温して更に３０分攪拌した。１３℃に保温したまま、ブチラール化度６５モル％、残存ビニルアルコールユニット２４．５モル％、残存酢酸ビニルユニット０．５モル％のポリビニルブチラール樹脂（積水化学社製、商品名エスレック）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％ＭＥＫ溶液）１．０８４ｇを添加して１５分間攪拌した。更に攪拌を続けながら、１２．４３ｇの添加液ａ、１．６ｍｌのＤｅｓｍｏｄｕｒＮ３３００／モーベイ社社製の脂肪族イソシアネート（１０％ＭＥＫ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。
【００６７】
【化１４】

【００６８】
〔マット剤分散液の調製〕
セルロースアセテートブチレート（Ｅａｓｔｍａｎ Ｃｈｅｍｉｃａｌ社、７．５ｇのＣＡＢ１７１−１５）をＭＥＫ４２．５ｇに溶解し、その中に、炭酸カルシウム（Ｓｐｅｃｉａｌｉｔｙ Ｍｉｎｅｒａｌｓ社、Ｓｕｐｅｒ−Ｐｆｌｅｘ２００）５ｇを添加し、ディゾルバ型ホモジナイザにて８０００ｒｐｍで３０ｍｉｎ分散しマット剤分散液を調製した。
〔表面保護層塗布液の調製〕
ＭＥＫ８６５ｇ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（ＶＳＣ）を１．５ｇ、ベンズトリアゾールを１．０ｇ添加し十分撹拌を行った。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。
〔感光層面側塗布〕
前記感光層塗布液と表面保護層塗布液をエクストルージョン型押し出しコーターを用いて、前記作製した各プラスチックフィルムの下引層２の上に、同時に重層塗布することにより熱現像感光材料を作製した。塗布は、感光層は塗布銀量１．９ｇ／ｍ²、表面保護層は乾燥膜厚で２．５μｍになる様にして行った。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、熱現像感光材料試料１を作製した。表１に示す様にバック層に添加する例示化合物の種類と量を変化させ熱現像感光材料試料２〜１０とした。
《熱現像感光材料試料の評価》
以上のようにして得られた試料１〜１０に下記に示す評価を行った。
（現像直後の捌き性評価）
上記作製した各試料を、２３℃、５０％ＲＨの環境下で３日間保存した後、感光性層面側から、高周波重畳にて波長８００〜８２０ｎｍの縦マルチモード化された半導体レーザを露光源とした露光機にてレーザ走査により濃度１．０になるように露光を与えた。この際に、各試料の露光面と露光レーザ光の角度を７５度とした。
【００６９】
その後、ヒートドラムを有する自動現像機を用いて熱現像感光材料試料の保護層とドラム表面が接触するようにして、１１０℃で１５秒熱現像処理した。この、露光及び現像も２３℃、５０％ＲＨに調湿した部屋で行った。
【００７０】
１枚目の現像が終了後直ちに２枚目の試料を現像させた後、１枚目の試料の上に重ねた。このように１０枚の試料を連続して処理し１０枚の試料が重なった束を作製した。１０枚目の試料の現像が終了後、５分経過した時点で試料の束を卓上に置き、一番上の試料の端をつまみ、一気に引き抜いた。このときに引き抜いた試料以外の試料がつられて動く枚数を評価した。
【００７１】
ランク５：動く試料数はゼロ
ランク４：１枚の試料がわずかに動く
ランク３：２、３枚の試料が多少動く
ランク２：数枚の試料が動く
ランク１：一番上の試料を一気に引き抜けない
【００７２】
【表１】

【００７３】
表１から明らかなように、本発明の試料は熱現像処理直後の捌き性がヘイズを劣化させることなく改良されていることが判る。
【００７４】
実施例２
バック層には例示化合物を添加せず、表面保護層塗布液を下記のように変更した以外は実施例１と同様にして試料２１〜２７を作製した。
〔表面保護層塗布液の調製〕
ＭＥＫ８６５ｇ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（ＶＳＣ）を１．５ｇ、ベンズトリアゾールを１．０ｇ、メタノール８０ｇ中に例示化合物（表２に示す種類と添加量）を９．６ｇ含有した溶液を添加して十分に攪拌を行った。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。
《熱現像感光材料試料の評価》
以上のようにして作製した試料２１〜２７を、実施例１と同様にして評価を行った。結果を表２に示す。尚、添加量はバインダー１００質量部に対する質量部で表す。
【００７５】
【表２】

【００７６】
表２から明らかなように、本発明の試料は熱現像処理直後の捌き性がヘイズを劣化させることなく改良されていることが判る。
【００７７】
実施例３
実施例１のバック層と実施例２の表面保護層を表３のように組み合わせて試料３１〜３９を作製し、同様に評価を行った。結果を表３に示す。
【００７８】
【表３】

【００７９】
表３から明らかなように、本発明の試料は熱現像処理直後の捌き性がヘイズを劣化させることなく改良されていることが判る。特にバック層と表面保護層に例示化合物の何れかを添加した場合には、その効果は更に発揮され、優れた効果を奏している。
【００８０】
【発明の効果】
熱現像感光材料のヘイズを劣化させることなく、熱現像処理直後の捌き性を改良することが出来るという顕著に優れた効果を奏する。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a silver halide photographic light-sensitive material for heat development containing an organic silver salt, in which the specific material is contained in the outermost layer binder to improve the spreadability of a film laminated after heat development.
[0002]
[Prior art]
Silver halide light-sensitive materials that have been widely used in the past have been used in the field of image formation as a broader and higher-quality material due to their excellent photographic characteristics, but development, fixing, The process of washing with water and drying is necessary, and the processing steps are wet, so that the work is complicated. For this reason, a silver halide photographic light-sensitive material for heat development, in which the development process is carried out by heat treatment, has been developed and put into practical use, and has recently been rapidly spread mainly in the medical industry.
[0003]
Such techniques include, for example, U.S. Pat. Nos. 3,152,904, 3,487,075, and D.C. As described in Morgan, “Dry Silver Photographic Materials” (Handbook of Imaging Materials, Marcel Dekker, Inc. page 48, 1991), etc. Also known are silver salt photothermographic dry imaging materials having photosensitive silver halide grains and a reducing agent. Since this silver salt photothermographic dry imaging material (a silver halide photographic light-sensitive material for heat development) does not use any solution processing chemicals, a simpler system can be provided to the user.
[0004]
In such a silver halide photographic light-sensitive material for heat development, the film is heated to 100 to 150 ° C. and subjected to development processing. However, it has become a new problem to improve the temperability immediately after heat development. For example, in the heat-developable silver halide photographic light-sensitive material that is developed by heating the film at 115 ° C. for 30 seconds, the films immediately after the development are stacked, and then when the films are taken out one by one from the bundle of films, Adjacent films were also dragged and moved to reduce work efficiency, and improvements were desired. As a method for improving the spreadability, there is a method using a large amount of a matting agent. However, the haze value of the film is increased, and the amount of matting agent used is also limited.
[0005]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and its purpose is to improve the silver halide photographic light-sensitive material for heat development (heat-developable light-sensitive material) in which scratches, in particular, the scratchability immediately after the heat development treatment are improved without deteriorating the haze. (Also called).
[0006]
[Means for Solving the Problems]
The above object of the present invention has been achieved by the following constitution.
[0007]
  Contains any of the compounds represented by the above general formulas (1) to (4)It has the following binderHas a surface layerHeatSilver halide photographic material for developmentThe silver halide photographic photosensitive material for heat development, wherein the compound represented by the general formulas (1) to (4) is 3 to 40 parts by mass with respect to 100 parts by mass of the binder of the surface layer, respectively. material.
Binder: Polyvinyl butyral, cellulose acetate butyrate or styrene-butadiene
[0008]
These compounds represented by the general formulas (1) to (4) are disclosed in JP-A-48-91165, JP-A-49-121523, JP-A-49-121523, JP-A-51-42535, It can be synthesized with reference to a known method such as Sho 54-18728.
[0009]
Although the example of the compound shown by the said General formula (1)-(4) is enumerated, it does not specifically limit.
[0010]
[Chemical formula 5]

[0011]
[Chemical 6]

[0012]
[Chemical 7]

[0013]
[Chemical 8]

[0014]
The surface layer in the present invention is a layer forming a substantial surface on the emulsion layer (photosensitive layer) side of the photothermographic material and a layer forming a substantial surface on the backing layer side. Here, the “layer forming a substantial surface” may be a layer having a film thickness of 0.3 μm or more, and an overcoat layer having a film thickness of 0.2 μm or less may be provided on the same layer.
[0015]
The binder of the surface layer may be a polymer that dissolves in an organic solvent such as methyl ethyl ketone such as polyvinyl butyral resin, cellulose acetate butyrate, or various latexes that are dispersed in an aqueous solvent such as styrene-butadiene latex. good. A polymer that is soluble in the former organic solvent is preferred.
[0016]
Although the usage-amount in the surface layer of the compound shown by General formula (1)-(4) is not specifically limited, 3-40 mass parts is preferable when the binder of a surface layer is 100 mass parts.
[0017]
Examples of the effect obtained by adding the above-described compound to the surface layer include improving the curling property of the film immediately after heat development. Although its action is unknown, it is presumed that the film surface has undergone a tribological change.
[0018]
The structure of the photothermographic material will be described below.
The photothermographic material of the present invention is usually composed of at least two layers in which at least one photosensitive layer and a layer adjacent to the photosensitive layer are provided on a support, and on the opposite side of the photosensitive layer, if necessary. A back coat layer (BC layer), a protective layer and the like are appropriately provided. The photosensitive layer of the photothermographic material contains photosensitive silver halide grains that may be sensitized with a spectral sensitizing dye, and further, an organic silver salt serving as a silver source in the photosensitive layer or its adjacent layer, A reducing agent for developing a silver salt to form a silver image is contained. The photosensitive layer of the photothermographic material and the adjacent layer thereof contain a polymer binder, a hydrophilic binder, a hydrophobic binder, or latex that provides a field for thermal development. In the photothermographic material described above, an AI layer or a BC layer containing a dye for preventing irradiation or preventing halation is provided if necessary. The photosensitive layer of the photothermographic material can contain a color tone agent for adjusting the color tone of the silver image, if necessary.
[0019]
In the present invention, the organic silver salt is a reducible silver source, and silver salts of organic acids and heteroorganic acids, particularly long-chain (C10-30, preferably 15-25) aliphatic carboxylic acids and A silver salt of a nitrogen-containing heterocyclic compound is preferred. Organic or inorganic complexes described in Research Disclosure (hereinafter simply referred to as RD) 17029 and 29963 in which the ligand has a value of 4.0 to 10.0 as a total stability constant with respect to silver ions preferable. Examples of these suitable silver salts include the following.
[0020]
Silver salts of organic acids, for example, silver salts of gallic acid, succinic acid, behenic acid, stearic acid, arachidic acid, palmitic acid, lauric acid and the like. Silver carboxyalkylthiourea salts, for example, silver salts such as 1- (3-carboxypropyl) thiourea, 1- (3-carboxypropyl) -3,3-dimethylthiourea, aldehydes and hydroxy-substituted aromatic carboxylic acids Silver salts or complexes of polymer reaction products, for example, silver salts of reaction products of aldehydes (formaldehyde, acetaldehyde, butyraldehyde, etc.) and hydroxy-substituted acids (eg, salicylic acid, benzoic acid, 3,5-dihydroxybenzoic acid) Thru complexes, silver salts or complexes of thiones, such as 3- (2-carboxyethyl) -4-hydroxymethyl-4-thiazoline-2-thione and 3-carboxymethyl-4-thiazoline-2-thione Silver salt or complex, imidazole, pyrazole, urazole, 1,2,4-thiazole and 1H Complex or salt of nitrogen acid and silver selected from tetrazole, 3-amino-5-benzylthio-1,2,4-triazole and benztriazole, silver salt such as saccharin, 5-chlorosalicylaldoxime, and mercaptides Silver salt. Among these, preferable silver salts include silver behenate, silver arachidate, and silver stearate.
[0021]
Photosensitive silver halide grains that can be used in the present invention will be described. Incidentally, the photosensitive silver halide grain in the present invention is capable of absorbing visible light or infrared light by an intrinsic or artificial physicochemical method as an intrinsic property of a silver halide crystal, The silver halide crystal grains are processed and manufactured so that physicochemical changes can occur in the silver halide crystal and / or on the crystal surface when absorbing visible or infrared light.
[0022]
The silver halide grains themselves used in the present invention are P.I. Chifie et Physique Photographic (published by PaulMontel, 1967) by Glafkides. F. Duffin's Photographic Emission Chemistry (published by The Focal Press, 1966), V.C. L. It can be prepared as a silver halide grain emulsion using the method described in Making and Coating Photographic Emulsion (published by The Focal Press, 1964) by Zelikman et al. That is, any of an acidic method, a neutral method, an ammonia method, etc. may be used, and the formation of reacting a soluble silver salt and a soluble halogen salt may be any one of a one-side mixing method, a simultaneous mixing method, and a combination thereof. Of these methods, the so-called controlled double jet method of preparing silver halide grains while controlling the formation conditions is preferable. 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.
[0023]
The silver halide that can be used in the present invention preferably has a smaller average grain size in order to keep the white turbidity after image formation low and obtain good image quality, and the average grain size is preferably 0.2 μm or less. Is preferably 0.01 to 0.17 μm, particularly preferably 0.02 to 0.14 μm. The grain size here refers to the length of the edge of the silver halide grain when the silver halide grain is a so-called normal crystal of a cube or octahedron. Further, when the silver halide grain is a tabular grain, it means the diameter when converted into a circular image having the same area as the projected area of the main surface.
[0024]
Examples of the shape of the silver halide grains include cubes, octahedrons, tetrahedron grains, tabular grains, spherical grains, rod-like grains, and potato grains. Among these, in particular, cubes, octahedrons, 14 Planar and tabular silver halide grains are preferred.
[0025]
When tabular silver halide grains are used, the average aspect ratio is preferably 1.5 or more and 100 or less, more preferably 2 or more and 50 or less. These are described in US Pat. Nos. 5,264,337, 5,314,798, 5,320,958, etc., and the desired tabular grains can be easily obtained. Further, grains having rounded corners of silver halide grains can be preferably used.
[0026]
The silver halide grains used in the present invention can be chemically sensitized. For example, chemical sensitization with a compound that releases a chalcogen such as sulfur or a noble metal compound that releases a noble metal ion such as gold ion by the methods disclosed in Japanese Patent Application Nos. 12-057004 and 12-061942 The center (chemical sensitization nucleus) can be formed and imparted. In the present invention, it is preferably chemically sensitized with an organic sensitizer containing a chalcogen atom. These chalcogen atom-containing organic sensitizers are preferably compounds having groups capable of adsorbing to silver halide and unstable chalcogen atom sites.
[0027]
As these organic sensitizers, organic sensitizers having various structures disclosed in the specifications of JP-A-60-150046, JP-A-4-109240, JP-A-11-218874 and the like are used. Of these, at least one compound having a structure in which a chalcogen atom is bonded to a carbon atom or a phosphorus atom by a double bond is preferable.
[0028]
In addition to the above-described sensitization methods, reduction sensitization methods and the like can also be used. Examples of reduction sensitization shell-like compounds include ascorbic acid, thiourea dioxide, stannous chloride, hydrazine derivatives, and borane compounds. A silane compound, a polyamine compound, or the like can be used. Further, reduction sensitization can be performed by ripening the emulsion while maintaining the pH at 7 or higher or the pAg at 8.3 or lower.
[0029]
The photosensitive silver halide grains that can be used in the present invention are preferably subjected to spectral sensitization by adsorbing a spectral sensitizing dye. As spectral sensitizing dyes, cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, styryl dyes, hemicyanine dyes, oxonol dyes, hemioxonol dyes and the like can be used. For example, JP-A-63-159841, JP-A-60-140335, JP-A-63-231437, JP-A-63-259651, JP-A-63-304242, JP-A-63-15245, U.S. Pat. Nos. 4,740,455, 4,741,966, 4,751,175, and 4,835,096 can be used. Useful sensitizing dyes used in the present invention are, for example, documents described or cited in RD No. 17643 IV-A (December 1978, p.23) and No. 18431 X (August 1978, p.437). It is described in. In particular, it is preferable to use a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of various laser imagers and scanners. For example, those described in JP-A Nos. 9-34078, 9-54409 and 9-80679 are used. A compound is preferably used.
[0030]
Emulsions containing silver halide grains or organic silver salt grains used in the photothermographic material of the present invention do not substantially absorb dyes having no spectral sensitizing action or visible light, together with sensitizing dyes. A substance that exhibits a supersensitization effect may be included in the emulsion, whereby the silver halide grains may be supersensitized. Useful sensitizing dyes, combinations of dyes exhibiting supersensitization, and substances exhibiting supersensitization are described in RD 17643 (issued in December, 1978), page 23, Section J, or Japanese Patent Publication No. 9-25500. Those described in JP-A-43-4933, JP-A-59-19032, JP-A-59-192242, JP-A-5-341432 and the like can be used. In the present invention, in addition to the supersensitizer described above, the compound represented by the general formula (1) and the macrocyclic compound disclosed in Japanese Patent Application No. 12-070296 are used as the supersensitizer. it can.
[0031]
In the present invention, a silver saving agent can be used. The silver saving agent as used herein refers to a compound that can reduce the amount of silver necessary to obtain a certain silver image density. Various action mechanisms of the function of decreasing can be considered, but a compound having a function of improving the covering power of developed silver is preferable. Here, “developing silver covering power” refers to the optical density per unit amount of silver. Preferred examples of the silver saving agent include hydrazine derivative compounds, vinyl compounds, and quaternary onium compounds.
[0032]
Examples of reducing agents suitable for the present invention are described in US Pat. Nos. 3,770,448, 3,773,512, 3,593,863, and RDs 17029 and 29963. However, when using aliphatic carboxylic acid silver salt as the organic silver salt, two or more phenol groups are linked by an alkylene group or sulfur. At least one position adjacent to the hydroxy substitution position of the phenol group, particularly an alkyl group (for example, methyl group, ethyl group, propyl group, t-butyl group, cyclohexyl group, etc.) or acyl group (for example, acetyl group) Bisphenols in which two or more of the phenol groups substituted by a propionyl group or the like are connected by an alkylene group or sulfur are preferred.
[0033]
As described above, as described above, reducing agents having protons such as bisphenols and sulfonamidophenols are mainly used. As a result, active species capable of extracting these hydrogens are generated. It is preferable that the compound which can inactivate a reducing agent by containing is contained. Preferably, the colorless photo-oxidizing substance is preferably a compound capable of generating free radicals as reactive active species during exposure.
[0034]
Accordingly, any compound having these functions may be used, but an organic free radical composed of a plurality of atoms is preferred. A compound having any structure may be used as long as it has such a function and does not cause any particular adverse effect on the photothermographic material.
[0035]
In addition, as a compound that generates these free radicals, a carbocyclic or heterocyclic ring is used so that the generated free radicals are stable enough to be in contact with the reducing agent for a time sufficient to react with the reducing agent. Those having an aromatic group of the formula are preferred.
[0036]
In the present invention, a cross-linking agent may be used not only for film formation and development unevenness but also for the effect of suppressing fogging during storage and suppressing the generation of printout silver after development. Examples of the crosslinking agent used in the present invention include various crosslinking agents conventionally used for photographic light-sensitive materials, such as aldehyde-based, epoxy-based, ethyleneimine-based, vinyl described in JP-A-50-96216. Examples include sulfone-based, isocyanate-based compounds, sulfonic acid ester-based, acryloyl-based, carbodiimide-based, and silane compound-based crosslinking agents, among which isocyanate-based compounds, silane compounds, epoxy compounds, and acid anhydrides are preferable.
[0037]
Examples of suitable toning agents for use in the present invention include RD 17029, U.S. Pat. Nos. 4,123,282, 3,994,732, 3,846,136, and 4, For example, there are the followings. Imides (eg, succinimide, phthalimide, naphthalimide, N-hydroxy-1,8-naphthalimide); mercaptans (eg, 3-mercapto-1,2,4-triazole); phthalazinone derivatives or metals of these derivatives Salts (eg, phthalazinone, 4- (1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-dimethyloxyphthalazinone, and 2,3-dihydro-1,4-phthalazinedione); phthalazine and phthalate Combinations of acids (eg phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic acid); phthalazine and maleic anhydride, and phthalic acid, 2,3-naphthalenedicarboxylic acid or o-phenylene acid derivatives and Its anhydrides (eg phthalic acid, 4-methylphthalic acid, 4-ni A combination of at least one compound selected from Rofutaru acid and tetrachlorophthalic anhydride) and the like. Particularly preferred color tones are phthalazinone or a combination of phthalazine and phthalic acids and phthalic anhydrides.
[0038]
In the present invention, the surface layer of the photothermographic material (the photosensitive layer side or the non-photosensitive layer provided on the opposite side of the photosensitive layer with the support sandwiched) is handled before development and the image after thermal development. It is preferable to contain a matting agent in order to prevent damage, and it is preferable to contain 0.1 to 30% by mass ratio with respect to the binder. The material of the matting agent used in the present invention may be either organic or inorganic. Examples of inorganic substances include silica described in Swiss Patent No. 330,158 and the like, glass powder described in French Patent No. 1,296,995 and the like, and alkali described in British Patent No. 1,173,181 and the like. Earth metals or carbonates such as cadmium and zinc can be used as the matting agent. Examples of organic substances include starch described in U.S. Pat. No. 2,322,037 and the like, starch derivatives described in Belgian Patent 625,451 and British Patent 981,198, and Japanese Patent Publication No. 44-3643. Polyvinyl alcohol described, polystyrene or polymethacrylate described in Swiss Patent No. 330,158, polyacrylonitrile described in US Pat. No. 3,079,257, US Pat. No. 3,022,169 etc. An organic matting agent such as a polycarbonate can be used.
[0039]
In the present invention, a conductive compound such as a metal oxide and / or a conductive polymer can be included in the constituent layers in order to improve the chargeability. These may be contained in any layer, but are preferably contained in the undercoat layer, the backing layer, the layer between the photosensitive layer and the undercoat, and the like. In the present invention, the conductive compounds described in US Pat. No. 5,244,773, columns 14 to 20 are preferably used.
[0040]
In the photothermographic material of the present invention, a filter layer is formed on the same side as or opposite to the photosensitive layer in order to control the amount of light transmitted through the photosensitive layer or the wavelength distribution, or a dye or pigment is added to the photosensitive layer. It is preferable to contain.
[0041]
Examples of the support used in the photothermographic material of the present invention include plastic films such as polyethylene terephthalate, polycarbonate, polyethylene, polyvinyl acetal, cellulose ester, cellulose triacetate, nitrocellulose, and polyethylene naphthalate, glass, paper, and aluminum plate. A metal plate or the like is used.
[0042]
In the present invention, known compounds that absorb light in various wavelength regions can be used according to the color sensitivity of the photothermographic material. For example, when the photothermographic material according to the present invention is used as an image recording material by infrared light, a squarylium dye having a thiopyrylium nucleus (thiopyrylium squarylium dye) as disclosed in Japanese Patent Application No. 11-255557. And a squarylium dye having a pyrylium nucleus (pyrylium squarylium dye), a thiopyrylium croconium dye similar to a squarylium dye, or a pyrylium croconium dye is preferably used.
[0043]
The photothermographic material of the present invention may be formed by preparing a coating solution obtained by dissolving or dispersing the above-mentioned constituent layers in a solvent, applying a plurality of coating solutions simultaneously, and then performing a drying process. preferable. Here, "multiple simultaneous multi-layer coating" means that a coating solution for each constituent layer (for example, a photosensitive layer and a protective layer) is prepared, and when coating this onto a support, each layer is individually coated and dried repeatedly. In other words, it means that each constituent layer can be formed in such a state that simultaneous multilayer coating and drying can be performed. That is, the upper layer is provided before the remaining amount of the total solvent in the lower layer reaches 70% by mass or less. There are no particular restrictions on the method of applying multiple layers of each constituent layer simultaneously, and for example, a known method such as a bar coater method, curtain coating method, dipping method, air knife method, hopper coating method, or extrusion coating method may be used. Can do. Of these, a pre-weighing type coating method called an extrusion coating method is more preferable. Since the extrusion coating method does not volatilize on the slide surface unlike the slide coating method, it is suitable for precision coating and organic solvent coating. Although this coating method has been described on the side having the photosensitive layer, the same applies to the case of coating with undercoating when providing the backcoat layer.
[0044]
In the present invention, the development conditions vary depending on the equipment, apparatus, or means to be used, but it is characterized in that the information is fixed by heating and developing the information recording film exposed imagewise at a high temperature. is there. The latent image obtained after exposure is subjected to a photothermographic material at a moderately high temperature (for example, about 80 to 200 ° C., preferably about 100 to 200 ° C.) for a sufficient time (generally about 1 second to about 2 minutes). It can be developed by heating. When the heating temperature is 80 ° C. or lower, sufficient image density cannot be obtained in a short time. When the heating temperature is 200 ° C. or higher, the binder is melted, and not only the image itself, such as transfer to a roller, but also adversely affects the transportability and the developing machine. Effect. By heating, a silver image is generated by an oxidation-reduction reaction between an organic silver salt (which functions as an oxidizing agent) and a reducing agent. This reaction process proceeds without any supply of treatment liquid such as water from the outside.
[0045]
In the exposure of the photothermographic material of the present invention, it is desirable to use a light source suitable for the color sensitivity imparted to the photosensitive material. For example, when the photosensitive material is sensitive to infrared light, it can be applied to any light source as long as it is in the infrared light range, but the laser power is high and the photosensitive material can be transparent. In view of the above, an infrared semiconductor laser (780 nm, 820 nm) is more preferably used.
[0046]
In the present invention, the exposure is preferably performed by laser scanning exposure, but various methods can be adopted as the exposure method. For example, as a first preferred method, there is a method using a laser scanning exposure machine in which the angle formed by the exposure surface of the photosensitive material and the scanning laser beam is not substantially perpendicular.
[0047]
Here, “substantially not perpendicular” means that the angle that is closest to the vertical during laser scanning is preferably 55 ° to 88 °, more preferably 60 ° to 86 °, and even more preferably 65 °. It is at least 84 degrees and most preferably 70 degrees to 82 degrees.
[0048]
As a second method, the exposure in the present invention is preferably performed using a laser scanning exposure machine that emits a scanning laser beam that is a vertical multi. Compared with a single longitudinal mode scanning laser beam, image quality degradation such as occurrence of interference fringe-like unevenness is reduced.
[0049]
Furthermore, as a third aspect, it is also preferable to form an image by scanning exposure using two or more lasers.
[0050]
As such an image recording method using a plurality of lasers, it is used in an image writing means of a laser printer or a digital copying machine that writes an image for each line in one scan in response to a request for high resolution and high speed. For example, Japanese Patent Application Laid-Open No. 60-166916 is known. This is a method in which laser light emitted from a light source unit is deflected and scanned by a polygon mirror and imaged on a photosensitive layer via an fθ lens or the like, and this is a laser scanning optical device that is theoretically the same as a laser imager or the like. It is. In each of the image recording methods described above, as a laser used for scanning exposure, generally known solid lasers such as a ruby laser, a YAG laser, and a glass laser; a He—Ne laser, an Ar ion laser, and a Kr ion laser , CO₂Laser, CO laser, He-Cd laser, N₂Gas laser such as laser and excimer laser; InGaP laser, AlGaAs laser, GaAsP laser, InGaAs laser, InAsP laser, CdSnP₂Lasers, semiconductor lasers such as GaSb lasers; chemical lasers, dye lasers, etc. can be selected and used in a timely manner, but among these, semiconductor lasers with wavelengths of 600-1200 nm are used due to maintenance and light source size problems. It is preferable to use it. In lasers used in laser imagers and laser image setters, the beam spot diameter on the material exposure surface when scanning a photothermographic material is generally 5 to 75 μm as the short axis diameter and as the long axis diameter. The laser beam scanning speed can be set to an optimum value for each photosensitive material depending on the sensitivity and laser power at the laser oscillation wavelength unique to the photothermographic material.
[0051]
【Example】
The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to the following examples.
[0052]
Example 1
<Preparation of silver halide photographic material for heat development>
12 W / m on a biaxially stretched polyethylene terephthalate film that is 175 μm thick and colored to a blue density of 0.175²-After corona discharge so as to obtain an output of minutes, the following undercoat coating solution 1 is applied so that the dry film thickness becomes 0.9 μm, and 10 ° C. with dry air of 140 ° C. (dew point temperature: 12 ° C.). The undercoat layer 1 was formed by drying for 2 seconds.
(Undercoating liquid 1)
911 ml of pure water
73.0 ml of 30% aqueous solution of Compound-1
TRAX H-45 5.78ml
(Nippon Yushi Co., Ltd. anionic surfactant: adjusted to 2% solid content)
Ammonia water (active ingredient 0.5%) 9.9ml
Hardener (C-6: Active ingredient 20%) 2.02ml
Next, 7 W / m is applied to the undercoat layer 1.²-After corona discharge so that the output of the minute becomes, after applying the undercoat coating solution 2 below to a dry film thickness of 0.9 µm, 140 ° C (dew point temperature: 12 ° C) The undercoat layer 2 was formed by drying for 10 seconds with dry air, and then transported through a drying zone at 123 ° C. over 2 minutes to provide the undercoat layer 2 containing insulator particles.
[0053]
[Chemical 9]

[0054]
(Undercoat coating solution 2)
905 ml of pure water
59.29 ml of 30% aqueous solution of compound-2
TRAX H-45 5.78ml
(Nippon Yushi Co., Ltd. anionic surfactant: adjusted to 2% solid content)
Insulator particles: Solution of ultrasonic dispersion of silicia 350 (manufactured by Fuji Silysia Chemical)
(Solid content concentration 1%) 33.56 ml
[0055]
[Chemical Formula 10]

[0056]
The undercoat coating solution 2 was used for coating after ultrasonic dispersion under the following conditions.
[0057]
Dispersion conditions: frequency = 25 kHz, output = 100 W, vibrator outer dimensions = 64φ × 300 mm, dispersion time = 20 minutes
Subsequently, the undercoat layer 2 was subjected to an undercoat process on the opposite side of the plastic film with a method similar to the above.
[0058]
Using the plastic film sample prepared above, each component layer prepared by the following method was applied in sequence.
(Application on the back side)
While stirring 830 g of methyl ethyl ketone (MEK), 84.2 g of cellulose acetate butyrate (Eastman Chemical, CAB381-20) and 4.5 g of a polyester resin (Bostic, VitelPE2200B) were added and dissolved. Next, 0.30 g of infrared dye-1 was added to the dissolved liquid, and a solution containing 8.4 g of Exemplified Compound 1-3 in 70 g of methanol was further added and sufficiently stirred. Finally, 75 g of silica (WR Grace, Syloid 64X6000) dispersed in MEK at a concentration of 1% by mass with a dissolver type homogenizer was added and stirred to prepare a coating solution on the back surface side.
[0059]
Embedded image

[0060]
The back surface coating solution thus prepared was applied and dried on the undercoat layer 2 of each of the produced plastic films by an extrusion coater so that the dry film thickness was 3.5 μm. It dried for 5 minutes using the drying air with a drying temperature of 100 degreeC, and dew point temperature of 10 degreeC.
(Coating on the photosensitive layer side)
[Preparation of photosensitive silver halide emulsion A]
<Solution A1>
Phenylcarbamoylated gelatin 88.3g
Compound (A) (10% methanol aqueous solution) 10 ml
Potassium bromide 0.32g
Finish to 5429 ml with water
<Solution B1>
0.67 mol / L silver nitrate aqueous solution 2635 ml
<Solution C1>
Potassium bromide 51.55g
Potassium iodide 1.47g
Finish to 660ml with water
<Solution D1>
Potassium bromide 154.9g
4.41 g of potassium iodide
Iridium chloride (1% solution) 0.93ml
Finish to 1982ml with water
<Solution E1>
0.4 mol / L potassium bromide aqueous solution The following silver potential control amount
<Solution F1>
Potassium hydroxide 0.71g
Finish to 20ml with water
<Solution G1>
56% acetic acid aqueous solution 18.0 ml
<Solution H1>
Anhydrous sodium carbonate 1.72 g
Finish to 151ml with water
Compound (A):
HO (CH₂CH₂O)_n-(CH (CH_Three) CH₂O)₁₇-(CH₂CH₂O)_mH
(M + n = 5-7)
Using a mixing stirrer shown in Japanese Patent Publication No. 58-58288, the solution A1 was controlled to a 1/4 amount of the solution B1 and the total amount of the solution C1 to a temperature of 45 ° C. and a pAg of 8.09. Was added to perform nucleation. After 1 minute, the entire amount of solution F1 was added. During this time, the pAg was appropriately adjusted using the solution E1. After 6 minutes, 3/4 amount of the solution B1 and the whole amount of the solution D1 were added over 14 minutes and 15 seconds by the simultaneous mixing method while controlling the temperature at 45 ° C. and pAg 8.09. After stirring for 5 minutes, the temperature was lowered to 40 ° C., the whole amount of the solution G1 was added, and the silver halide emulsion was precipitated. The supernatant was removed leaving 2000 ml of the sedimented portion, 10 L of water was added, and after stirring, the silver halide emulsion was sedimented again. The remaining portion of 1500 ml was left, the supernatant was removed, 10 L of water was further added, and after stirring, the silver halide emulsion was precipitated. After leaving 1500 ml of the sedimented portion and removing the supernatant, 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 that the amount of silver was 1161 g per mole of silver, whereby photosensitive silver halide emulsion A was obtained.
[0061]
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%.
[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 sodium hydroxide aqueous solution was added and 6.9 ml of concentrated nitric acid was added, followed by cooling to 55 ° C. to obtain a fatty acid sodium solution. While maintaining the temperature of the fatty acid sodium solution at 55 ° C., 45.3 g of the photosensitive silver halide emulsion A and 450 ml of pure water were added and stirred for 5 minutes.
[0062]
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 and stirred, and then allowed to stand to float and separate the organic silver salt dispersion, thereby removing the lower water-soluble salts. Thereafter, washing with deionized water and drainage were repeated until the electrical conductivity of the drainage reached 2 μS / cm, and centrifugal dehydration was carried out. Then, the resulting cake-like organic silver salt was converted into an airflow dryer flash jet dryer (stock) The product was dried until the water content became 0.1% according to the operating conditions of nitrogen gas atmosphere and dryer inlet hot air temperature to obtain a dried organic silver salt A of organic silver salt. In addition, the infrared moisture meter was used for the moisture content measurement of an organic silver salt composition.
[Preparation of Preliminary Dispersion A]
14.57 g of polyvinyl butyral powder (Monsanto, Butvar B-79) was dissolved in 1457 g of methyl ethyl ketone, and 500 g of powdered organic silver salt A was gradually added while stirring with a dissolver DISPERMAT CA-40M manufactured by VMA-GETZMANN. Preliminary dispersion A was prepared by thorough mixing.
[Preparation of photosensitive emulsion dispersion 1]
Media-type disperser filled with 80% of the internal volume of 0.5 mm diameter zirconia beads (Traceram manufactured by Toray Industries, Inc.) so that the pre-dispersion liquid A is 1.5 minutes using a pump. A photosensitive emulsion dispersion 1 was prepared by supplying to a DISPERMAT SL-C12EX type (manufactured by VMA-GETZMANN) and dispersing at a mill peripheral speed of 8 m / s.
(Preparation of stabilizer solution)
A stabilizer solution was prepared by dissolving 1.0 g of Stabilizer-1 and 0.31 g of potassium acetate in 4.97 g of methanol.
[Preparation of infrared sensitizing dye liquid A]
19.2 mg of infrared sensitizing dye 1, 1.488 g 2-chloro-benzoic acid, 2.7779 g stabilizer-2 and 365 mg 5-methyl-2-mercaptobenzimidazole in 31.3 ml MEK Infrared sensitizing dye solution A was prepared by dissolving at this point.
[0063]
Embedded image

[0064]
[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, 0.48 g of the infrared dye-1 Was dissolved in 110 g of MEK to obtain an additive solution a.
[Preparation of additive liquid b]
3.56 g of antifoggant-2 and 3.43 g of phthalazine were dissolved in 40.9 g of MEK to obtain additive liquid b.
[0065]
Embedded image

[0066]
[Preparation of photosensitive layer coating solution]
In an inert gas atmosphere (97% nitrogen), the photosensitive emulsion dispersion 1 (50 g) and 15.11 g of MEK were kept at 21 ° C. with stirring, and the chemical sensitizer S-5 (0.5% methanol solution) was stirred. ) 1000 μl was added, and after 2 minutes, 390 μl of antifoggant-1 (10% methanol solution) was added and stirred for 1 hour. Further, 494 μl of calcium bromide (10% methanol solution) was added and stirred for 10 minutes, and then a gold sensitizer Au-5 corresponding to 1/20 mole of the chemical sensitizer S-5 was added, and further 20 minutes. Stir. Subsequently, 167 ml of a stabilizer solution was added and stirred for 10 minutes, and then 1.32 g of the infrared sensitizing dye solution A was added and stirred for 1 hour. Thereafter, the temperature was lowered to 13 ° C. and further stirred for 30 minutes. While maintaining the temperature at 13 ° C., polyvinyl butyral resin having a butyralization degree of 65 mol%, a residual vinyl alcohol unit of 24.5 mol%, and a residual vinyl acetate unit of 0.5 mol% (Sekisui Chemical Co., Ltd., trade name S-REC) 13.31 g After stirring for 30 minutes, 1.084 g of tetrachlorophthalic acid (9.4 mass% MEK solution) was added and stirred for 15 minutes. While further stirring, 12.43 g of additive liquid a, 1.6 ml of Desmodur N3300 / Mobey aliphatic isocyanate (10% MEK solution), 4.27 g of additive liquid b were sequentially added and stirred. A photosensitive layer coating solution was obtained.
[0067]
Embedded image

[0068]
(Preparation of matting agent dispersion)
Cellulose acetate butyrate (Eastman Chemical Co., 7.5 g CAB171-15) was dissolved in 42.5 g of MEK, and 5 g of calcium carbonate (Speciality Minerals, Super-Pflex 200) was added thereto, and a dissolver type homogenizer was used. A matting agent dispersion was prepared by dispersing at 8000 rpm for 30 minutes.
(Preparation of surface protective layer coating solution)
While stirring MEK865g, cellulose acetate butyrate (Eastman Chemical Co., CAB171-15) 96g, polymethylmethacrylic acid (Rohm & Haas Co., Paraloid A-21) 4.5g, vinyl sulfone compound (VSC) 1 0.5 g and 1.0 g of benztriazole were added and sufficiently stirred. Next, 30 g of the above matting agent dispersion was added and stirred to prepare a surface protective layer coating solution.
(Photosensitive layer side coating)
The photothermographic material was produced by simultaneously applying the photosensitive layer coating solution and the surface protective layer coating solution on the undercoat layer 2 of each of the produced plastic films using an extrusion type extrusion coater. For coating, the photosensitive layer has a coated silver amount of 1.9 g / m.²The surface protective layer was formed so as to have 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 photothermographic material sample 1. As shown in Table 1, the types and amounts of the exemplary compounds added to the back layer were changed to obtain photothermographic material samples 2 to 10.
<< Evaluation of Photothermographic Material Sample >>
The samples 1 to 10 obtained as described above were evaluated as follows.
(Evaluation of scratchability immediately after development)
Each of the prepared samples was stored for 3 days in an environment of 23 ° C. and 50% RH, and then a semiconductor laser having a wavelength of 800 to 820 nm and having a wavelength of 800 to 820 nm by high frequency superposition from the photosensitive layer surface side as an exposure source. The exposure was performed with the exposure machine so that the density was 1.0 by laser scanning. At this time, the angle between the exposure surface of each sample and the exposure laser beam was set to 75 degrees.
[0069]
Thereafter, the film was subjected to heat development at 110 ° C. for 15 seconds using an automatic developing machine having a heat drum so that the protective layer of the photothermographic material sample was in contact with the drum surface. The exposure and development were also performed in a room conditioned at 23 ° C. and 50% RH.
[0070]
Immediately after the development of the first sheet was completed, the second sample was developed, and then superimposed on the first sheet. In this way, 10 samples were continuously processed to produce a bundle in which 10 samples overlapped. After the development of the tenth sample was completed, when 5 minutes had passed, the sample bundle was placed on the table, the edge of the uppermost sample was pinched and pulled out all at once. At this time, the number of samples other than the sample pulled out and moved was evaluated.
[0071]
Rank 5: Zero moving samples
Rank 4: One sample moves slightly
Rank 3: Two or three samples move slightly
Rank 2: several samples move
Rank 1: The top sample cannot be pulled out at once
[0072]
[Table 1]

[0073]
As is apparent from Table 1, it can be seen that in the sample of the present invention, the spreadability immediately after the heat development treatment is improved without deteriorating the haze.
[0074]
Example 2
Samples 21 to 27 were prepared in the same manner as in Example 1 except that the exemplary compound was not added to the back layer and the surface protective layer coating solution was changed as follows.
(Preparation of surface protective layer coating solution)
While stirring MEK865g, cellulose acetate butyrate (Eastman Chemical Co., CAB171-15) 96g, polymethylmethacrylic acid (Rohm & Haas Co., Paraloid A-21) 4.5g, vinyl sulfone compound (VSC) 1 A solution containing 9.6 g of the exemplified compound (type and addition amount shown in Table 2) in 0.5 g, 1.0 g of benztriazole, and 80 g of methanol was added and sufficiently stirred. Next, 30 g of the above matting agent dispersion was added and stirred to prepare a surface protective layer coating solution.
<< Evaluation of Photothermographic Material Sample >>
Samples 21 to 27 produced as described above were evaluated in the same manner as in Example 1. The results are shown in Table 2. The added amount is expressed in parts by mass with respect to 100 parts by mass of the binder.
[0075]
[Table 2]

[0076]
As is apparent from Table 2, it can be seen that in the sample of the present invention, the spreadability immediately after the heat development treatment is improved without deteriorating the haze.
[0077]
Example 3
Samples 31 to 39 were prepared by combining the back layer of Example 1 and the surface protective layer of Example 2 as shown in Table 3, and were similarly evaluated. The results are shown in Table 3.
[0078]
[Table 3]

[0079]
As can be seen from Table 3, it can be seen that the samples of the present invention have improved haze properties immediately after heat development without deteriorating haze. In particular, when any of the exemplified compounds is added to the back layer and the surface protective layer, the effect is further exhibited, and an excellent effect is achieved.
[0080]
【The invention's effect】
There is a remarkably excellent effect that it is possible to improve the spreadability immediately after the heat development process without deteriorating the haze of the photothermographic material.

Claims (4)

A silver halide photographic material for heat development having a surface layer comprising the following binder containing the compound represented by the following general formula (1), wherein the compound represented by the general formula (1) is a surface layer: A silver halide photographic light-sensitive material for heat development, which is 3 to 40 parts by mass with respect to 100 parts by mass of the binder.

In the formula, R ₁ , R ₂ , R ₃ and R ₄ are substituted or unsubstituted alkyl groups having 1 to 4 carbon atoms, A ₁ and B ₁ are alkylene groups having 1 to 6 carbon atoms, methyl hydroxide group, A phenylene group or a simple bond, X ⁻ represents an anion, and n1 represents a positive integer.
Binder: Polyvinyl butyral, cellulose acetate butyrate or styrene-butadiene A silver halide photographic light-sensitive material for heat development having a surface layer comprising the following binder containing a compound represented by the following general formula ( 2 ), wherein the compound represented by the general formula ( 2 ) is a surface layer: A silver halide photographic light-sensitive material for heat development, which is 3 to 40 parts by mass with respect to 100 parts by mass of the binder.

Wherein, R _5, R _6, R ₇ and R ₈ represents a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, R ₅ and R ₇ and / or R ₆ and R ₈ are bonded to the nitrogen-containing A heterocycle may be formed. A ₂ and B ₂ each represent a linear or branched alkylene group, a xylylene group, or a cyclohexylene group, and the linear or branched alkylene is a double bond, triple bond, or — (CH _{2) in the} alkylene. _{-CH 2 -O) y -CH 2 -CH} 2 - may have. X ⁻ represents an anion, n2 represents a positive integer, and y represents 1 to 20.
Binder: Polyvinyl butyral, cellulose acetate butyrate or styrene-butadiene A silver halide photographic material for heat development having a surface layer comprising the following binder containing a compound represented by the following general formula ( 3 ), wherein the compound represented by the general formula ( 3 ) is a surface layer: A silver halide photographic light-sensitive material for heat development, which is 3 to 40 parts by mass with respect to 100 parts by mass of the binder.

In the formula, R ₉ and R ₁₀ each represents an alkyl group, a cycloalkyl group, an aralkyl group, an aryl group or an alkenyl group, and R ₉ and R ₁₀ may be bonded to each other to form an alkylene chain. R ₁₁ represents an alkylene group or aralkylene group having 10 or less carbon atoms. X ⁻ represents an anion, and n3 represents a positive integer.
Binder: Polyvinyl butyral, cellulose acetate butyrate or styrene-butadiene A silver halide photographic light-sensitive material for heat development having a surface layer comprising the following binder containing a compound represented by the following general formula ( 4 ), wherein the compound represented by the general formula ( 4 ) is a surface layer: A silver halide photographic light-sensitive material for heat development, which is 3 to 40 parts by mass with respect to 100 parts by mass of the binder.

In the formula, A ₃ is an alkylene group having 2 to 18 carbon atoms, alkenylene group, arylene group, aralkylene group, arylene alkylene group, —R ₁₂ COR ₁₃ — group, —R ₁₄ COR ₁₅ COR ₁₆ — group, —R ₁₇ —. (OR ₁₈ ) _m group, —R ₁₉ COOR ₂₀ OCOR ₂₁ — group, —R ₂₂ OCONHR ₂₃ NHCOOR ₂₄ — group, —R ₂₅ CONHR ₂₆ NHCOR ₂₇ — group, B ₃ is a simple bond, —NHCOR ₂₈ CONH— Represents a group or a group selected from A ₃ . Here, R ₁₂ to R ₂₈ are an alkylene group or phenylene group having 1 to 10 carbon atoms, and m represents an integer of 1 to 4. Z ₁ and Z ₂ represent an atomic group necessary for forming a 5- or 6-membered ring with —N═C— group, X ⁻ represents an anion, and n4 represents a positive integer.
Binder: Polyvinyl butyral, cellulose acetate butyrate or styrene-butadiene