JP3727364B2 - Direct positive silver halide emulsion and color diffusion transfer photosensitive material using the same - Google Patents

Description

【００４３】
以下に、本発明に含まれる各構成要素について順次説明する。
Ｉ．感光シート
Ａ）支持体
本発明に用いられる感光シートの支持体は写真感光材料に通常用いられる平滑な透明支持体なら、いずれでも用いられ、酢酸セルロース、ポリスチレン、ポリエチレンテレフタレート、ポリカーボネートなどが用いられ、下塗り層を設けるのが好ましい。支持体は通常ライトパイピングを防止する為微量の染料または酸化チタンの如き顔料を含有しているのが好ましい。
支持体の厚さは５０〜３５０μｍ、好ましくは７０〜２１０μｍ、更に好ましくは８０〜１５０μｍ、である。
必要に応じて支持体のバック側にはカールバランスをとる層または特開昭５６−７８８３３号に記載の酸素遮断性の層をつけることができる。
【００４４】
Ｂ）受像層
本発明に用いられる染料受像層は親水性コロイド中に媒染剤を含むものである。これは単一の層であっても、また媒染力の異なる媒染剤が重ねて塗設された多層構成のものでもよい。これについては特開昭６１−２５２５５１に記載されている。媒染剤としては、ポリマー媒染剤が好ましい。
ポリマー媒染剤とは二級および三級アミノ基を含むポリマー、含窒素複素環部分をもつポリマー、および４級カチオンを含むポリマーなどで分子量が５，０００以上のもの特に好ましくは１０，０００以上のものである。
媒染剤の塗設量は、一般的には０．５〜１．０ｇ／m²好ましくは１．０〜５．０ｇ／m²特に好ましくは２〜４ｇ／m²である。
受像層に使用する親水性コロイドとしては、ゼラチン、ポリビニルアルコール、ポリアクリルアミド、ポリビニルピロリドンなどが使用されるがゼラチンが好ましい。
受像層中には、特公昭６２−３０６２０号や同６２−３０６２１号、特開昭６２−２１５，２７２号記載の退色防止剤を組み込むことができる。
【００４５】
Ｃ）白色反射層
色画像の白背景を成す白色反射層は通常白色顔料と親水性バインダーを含む。
白色反射層用の白色顔料としては、硫酸バリウム、酸化亜鉛、ステアリン酸バリウム、銀フレーク、ケイ酸塩類、アルミナ、酸化ジルコニウム、ジルコニウム硫酸ソーダ、カオリン、雲母、二酸化チタンなどが使用される。更に、スチレンなどよりなる非造膜性のポリマー粒子なども使用される。又これらは、単独で使用しても良いし、望まれる反射率を得られる範囲で混合して用いることもできる。
特に有用な白色顔料は、二酸化チタンである。
白色反射層の白色度は、顔料の種類、顔料とバインダーの混合比率および顔料の塗布量によって変るが、光反射率が７０％以上であることが望ましい。一般に、顔料の塗布量が増えるほど、白色度が向上するが、この層を通って画像形成色素が拡散するとき、顔料が色素の拡散に対して抵抗となるので、適度の塗布量をもつことが望ましい。
二酸化チタンを５〜４０ｇ／m²、好ましくは、１０〜２５ｇ／m²塗布し、光反射率が５４０mmの波長の光で７８〜８５％を有する白色反射層が好ましい。
二酸化チタンは、市販の種々の銘柄より選んで用いることができる。
この中でも特にルチル型の二酸化チタンを用いるのが好ましい。
市販品の多くは、アルミナやシリカや酸化亜鉛などで表面処理が行なわれており、高い反射率を得るには、表面処理量が５％以上のものが望ましい。市販されている二酸化チタンとしては、例えば、デュポン社の Ti-pureＲ９３１の他、リサーチ・ディスクロージャー誌１５１６２号に記載のものがある。
白色反射層のバインダーとしては、アルカリ浸透性の高分子マトリックス、例えばゼラチン、ポリビニルアルコールやヒドロキシエチルセルロース、カルボキシルメチルセルロースのようなセルロース誘導体が使用できる。
白色反射層の特に望ましいバインダーはゼラチンである。白色顔料とゼラチンの比は１／１〜２０／１（重量比）、望ましくは５／１〜１０／１（重量比）である。
白色反射層中には、特公昭６２−３０６２０号や同６２−３０６２１号のような褪色防止剤を組み込むことが好ましい。
【００４６】
Ｄ）遮光層
白色反射層と感光性層の間には遮光剤および親水性バインダーを含む遮光層を設けてもよい。
遮光剤としては、遮光機能を有する材料のいずれも用いられるが、カーボンブラックが好ましく用いられる。また米国特許第４，６１５，９６６号等に記載の分解性の染料を用いてもよい。
遮光剤を塗設するバインダーとしてはカーボンブラックを分散しうるものならいずれでもよく、好ましくはゼラチンである。
カーボンブラック原料としては、例えば Donnel Voet “Carbon Black" Marcel Dekker,Inc.（１９７６）に記載されているようなチャンネル法、サーマル法及びファーネス法など任意の製法のものが使用できる。カーボンブラックの粒子サイズは特に限定されないが９０〜１８００Åのものが好ましい。遮光剤としての黒色顔料の添加量は遮光すべき感光材料の感度に応じて量を調節すればよいが、光学濃度で５〜１０程度が望ましい。
【００４７】
Ｅ）感光層
本発明においては、前記遮光層の上方に色素像形成物質と組合わされたハロゲン化銀乳剤層から成る感光層を設ける。以下でその構成要素について述べる。
(1) 色素像形成物質
本発明に用いられる色素像形成物質は、銀現像に関連して拡散性色素（色素プレカーサーでもよい）を放出する非拡散性化合物であるか、あるいはそれ自体の拡散性が変化するものであり、「写真プロセスの理論」(The Theory of the Photographic Process)第４版に記載されている。これらの化合物は、いずれも下記一般式〔Ｉ〕で表すことができる。
一般式〔Ｉ〕
（ＤＹＥ−Ｙ）_n −Ｚ
｛ＤＹＥは色素基、一時的に短波化された色素基または色素前駆体基を表し、Ｙは単なる結合又は連結基を表し、Ｚは画像状に潜像を有する感光性銀塩に対応又は逆対応して（ＤＹＥ−Ｙ）_n −Ｚで表される化合物の拡散性に差を生じさせるか、又は、ＤＹＥを放出し、放出されたＤＹＥと（ＤＹＥ−Ｙ）_n −Ｚとの間に拡散性において差を生じさせるような性質を有する基を表し、ｎは１または２を表し、ｎが２の時、２つのＤＹＥ−Ｙは同一でも異なっていてもよい。｝
このＺの機能により、銀現像部で拡散性となるネガ型化合物と未現像部で拡散性となるポジ型化合物とに大別される。
ネガ型のＺの具体例としては、現像の結果酸化し、開裂して拡散性色素を放出するものがあげられる。
Ｚの具体例は米国特許３，９２８，３１２号、同３，９９３，６３８号、同４，０７６，５２９号、同４，１５２，１５３号、同４，０５５，４２８号、同４，０５３，３１２号、同４，１９８，２３５号、同４，１７９，２９１号、同４，１４９，８９２号、同３，８４４，７８５号、同３，４４３，９４３号、同３，７５１，４０６号、同３，４４３，９３９号、同３，４４３，９４０号、同３，６２８，９５２号、同３，９８０，４７９号、同４，１８３，７５３号、同４，１４２，８９１号、同４，２７８，７５０号、同４，１３９，３７９号、同４，２１８，３６８号、同３，４２１，９６４号、同４，１９９，３５５号、同４，１９９，３５４号、同４，１３５，９２９号、同４，３３６，３２２号、同４，１３９，３８９号、特開昭５３−５０７３６号、同５１−１０４３４３号、同５４−１３０１２２号、同５３−１１０８２７号、同５６−１２６４２号、同５６−１６１３１号、同５７−４０４３号、同５７−６５０号、同５７−２０７３５号、同５３−６９０３３号、同５４−１３０９２７号、同５６−１６４３４２号、同５７−１１９３４５等に記載されている。
ネガ型の色素放出レドックス化合物のＺのうち、特に好ましい基としてはＮ−置換スルファモイル基（Ｎ−置換基としては芳香族炭化水素環やヘテロ環から誘導される基）を挙げる事ができる。このＺの代表的な基を以下に例示するが、これらのみに限定されるものではない。
【００４８】
【化１】

【００４９】
ポジ型の化合物についはて、アンゲバンテ・ヘミ・インターナショナル・エデション・インイングリッシュ（Angev.Chem.Int.Ed.Engl.)、２２、１９１（１９８２）に記載されている。
具体例としては、当初アルカリ条件下では拡散性であるが、現像により酸化されて非拡散性となる化合物（色素現像薬）があげられる。この型の化合物に有効なＹとしては米国特許２９８３６０６号にあげられたものが代表的である。
また、別の型としては、アルカリ条件下で自己閉環するなどして拡散性色素を放出するが、現像に伴い酸化されると実質的に色素の放出がおこらなくなるようなものである。このような機能を持つＹの具体例については、米国特許３，９８０，４７９号、特開昭５３−６９０３３号、同５４−１３０９２７号、米国特許３，４２１，９６４号、同４，１９９，３５５号などに記載されている。
また別な型としては、それ自体は色素を放出しないが、還元されると色素を放出するものがある。この型の化合物は電子供与体とともに組合わせて用い、銀現像によって画像様に酸化した残りの電子供与体との反応によって像様に拡散性色素を放出させることが出来る。このような機能を持つ原子団については、例えば米国特許４，１８３，７５３号、同４，１４２，８９１号、同４，２７８，７５０号、同４，１３９，３７９号、同４，２１８，３６８号、特開昭５３−１１０８２７号、米国特許４，２７８，７５０号、同４，３５６，２４９号、同４，３５８，５３５号、特開昭５３−１１０８２７号、同５４−１３０９２７号、同５６−１６４３４２号、公開技報８７−６１９９号、欧州特許公開２２０７４６Ａ２号等に記載されている。
以下にその具体例を例示するが、これらのみに限定されるものではない。
【００５０】
【化２】

【００５１】
このタイプの化合物が使用される場合には耐拡散性電子供与化合物（ＥＤ化合物として周知）またはそのプレカーサー（前駆体）と組合わせて用いるのが好ましい。ＥＤ化合物の例としては例えば米国特許４，２６３，３９３号、同４，２７８，７５０号、特開昭５６−１３８７３６号等に記載されている。
また別の型の色素像形成物質の具体例としては、下記のものも使用できる。
【００５２】
【化３】

【００５３】
この詳細は米国特許３，７１９，４８９号や同４，０９８，７８３号に記載されている。
一方、前記の一般式のＤＹＥで表わされる色素の具体例は下記の文献に記載されている。
イエロー色素の例：
米国特許３，５９７，２００号、同３，３０９，１９９号、同４，０１３，６３３号、同４，２４５，０２８号、同４，１５６，６０９号、同４，１３９，３８３号、同４，１９５，９９２号、同４，１４８，６４１号、同４，１４８，６４３号、同４，３３６，３２２号：特開昭５１−１１４９３０号、同５６−７１０７２号：Research Disclosure １７６３０（１９７８）号、同１６４７５（１９７７）号に記載されているもの。
マゼンタ色素の例：
米国特許３、４５３、１０７号、同３，５４４，５４５号、同３，９３２，３８０号、同３，９３１，１４４号、同３，９３２，３０８号、同３，９５４，４７６号、同４，２３３，２３７号、同４，２５５，５０９号、同４，２５０，２４６号、同４，１４２，８９１号、同４，２０７，１０４号、同４，２８７，２９２号：特開昭５２−１０６，７２７号、同５３−２３，６２８号、同５５−３６，８０４号、同５６−７３，０５７号、同５６−７１０６０号、同５５−１３４号に記載されているもの。
シアン色素の例：
米国特許３，４８２，９７２号、同３，９２９，７６０号、同４，０１３，６３５号、同４，２６８，６２５号、同４，１７１，２２０号、同４，２４２，４３５号、同４，１４２，８９１号、同４，１９５，９９４号、同４，１４７，５４４号、同４，１４８，６４２号；英国特許１，５５１，１３８号；特開昭５４−９９４３１号、同５２−８８２７号、同５３−４７８２３号、同５３−１４３３２３号、同５４−９９４３１号、同５６−７１０６１号；ヨーロッパ特許（ＥＰ）５３，０３７号、同５３，０４０号；Research Disclosure １７，６３０（１９７８）号、及び同１６，４７５（１９７７）号に記載されているもの。
これらの化合物は、特開昭６２−２１５，２７２号、１４４〜１４６頁記載の方法で分散することができる。また、これらの分散物には、特開昭６２−２１５，２７２号、１３７〜１４４頁記載の化合物を含ませてもよい。
【００５４】
（２）ハロゲン化銀乳剤
本発明では、前述の平板状内部潜像型直接ポジハロゲン化銀乳剤と組み合わせて以下の種々の形状の内部潜像型直接ポジハロゲン化銀乳剤を使用することができる。例として、立方体、八面体、十四面体、斜方十二面体のような規則的な結晶形を有するもの、また、球状、板状などのような変則的な結晶形を有するもの、高次の面（（ｈｋ１）面）をもつもの、あるいはこれらの結晶形の粒子の混合などを挙げることができる。高次の面を持つ粒子については、ジャーナル・オブ・イメージング・サイエンス（Journal of Imaging Science) 誌、第３０巻（１９８６年）の２４７頁から２５４頁を参照することができる。
本発明に用いるハロゲン化銀粒子は双晶面を含まない正常晶でも、日本写真学会編、写真工業の基礎、銀塩写真編（コロナ社）、ｐ．１６３に解説されているような例、例えば双晶面を一つ含む一重双晶、平行な双晶面を２つ以上含む平行多重双晶、非平行な双晶面を２つ以上含む非平行多重双晶などから目的に応じて選んで用いることができる。
また形状の異なる粒子を混合させる例が米国特許第４，８６５，９６４号に開示されているが、必要によりこの方法を選ぶことができる。
正常晶の場合には（１００）面からなる立方体、（１１１）面からなる八面体、特公昭５５−４２７３７号、特開昭６０−２２２８４２号に開示されている（１１０）面からなる十二面体粒子を用いることができる。さらに、Journal of Imaging Science誌、３０巻、２４７頁、１９８６年に報告されているような（２１１）を代表とする（ｈｌ１）面粒子、（３３１）を代表とする（ｈｈ１）面粒子、（２１０）面を代表とする（ｈｋ０）面粒子と（３２１）面を代表とする（ｈｋ１）面粒子も調製法に工夫を要するが目的に応じて選んで用いることができる。
（１１０）面と（１１１）面が一つの粒子に共存する十四面体粒子、（１００）面と（１１０）面が共存する粒子、あるいは（１１１）面と（１１０）面が共存する粒子など、２つの面あるいは多数の面が共存する粒子も目的に応じて選んで用いることができる。
【００５５】
これらの粒子のハロゲン化銀組成、乳剤の粒子サイズ、は前述の平板状内部潜像型直接ポジハロゲン化銀乳剤と同様なものを選べる。
【００５６】
本発明に用いるハロゲン化銀乳剤は欧州特許第９６，７２７Ｂ１号、同６４，４１２Ｂ１号などに開示されているような粒子に丸みをもたらす処理、あるいは西独特許第２，３０６，４４７Ｃ２号、特開昭６０−２２１３２０号に開示されているような表面の改質を行ってもよい。
粒子表面が平坦な構造が一般的であるが、意図して凹凸を形成することは場合によって好ましい。特開昭５８−１０６５３２号、同６０−２２１３２０号に記載されている結晶の一部分、例えば頂点あるいは面の中央に穴をあける方法、あるいは米国特許第４，６４３，９６６号に記載されているラッフル粒子がその例である。
【００５７】
これ等の晶癖、ハロゲン組成、粒子サイズ、粒子サイズ分布などが異なった２種以上のハロゲン化銀を併用することが可能であり、それぞれ異なる乳剤層及び／又は同一乳剤層に使用することが可能である。
【００５８】
以上説明したハロゲン化銀粒子は、リサーチ・ディスクロージャー（ＲＤ）No．１７６４３（１９７８年１２月）、２２〜２３頁、“Ｉ．乳剤製造（Emulsion preparation and types）”、及び同No．１８７１６（１９７９年１１月）、６４８頁、同No．３０７１０５（１９８９年１１月）、８６３〜８６５頁、及びグラフキデ著「写真の物理と化学」、ポールモンテル社刊（P.Glafkides Chimie et Pysique Photograhique,Paul Montel,１９６７）、ダフィン著「写真乳剤化学」、フォーカルプレス社刊（G.F.Duffin, Photographic Emulsion Chemistry,Focal Press,１９６６）、ゼリクマン等著「写真乳剤の製造と塗布」、フォーカルプレス社刊（V.L.Zelikman et al, Making and Coating Photographic Emulsion, Focal Press,１９６４）などに記載された方法を用いて調製することができる。すなわち、酸性法、中性法、アンモニア法等のいずれでもよく、また可溶性銀塩と可溶性ハロゲン塩を反応させる形式としては片側混合法、同時混合法、それらの組合わせなどのいずれを用いてもよい。粒子を銀イオン過剰の下において形成させる方法（いわゆる逆混合法）を用いることもできる。同時混合法の一つの形式としてハロゲン化銀の生成する液相中のｐＡｇを一定に保つ方法、すなわちいわゆるコントロールド・ダブルジェット法を用いることもできる。この方法によると、結晶形が規則的で粒子サイズが均一に近いハロゲン化銀乳剤が得られる。
【００５９】
前記の正常晶からなるハロゲン化銀粒子は、粒子形成中のｐＡｇとｐＨを制御することにより得られる。詳しくは、例えばフォトグラフィック・サンエンス・アンド・エンジニアリング（Photographic Science and Engineering）、第６巻、１５９〜１６５頁（１９６２）；ジャーナル・オブ・フォトグラフィック・サンエンス（Journal of Photographic Science)、１２巻、２４２〜２５１頁（１９６４）、米国特許第３，６５５，３９４号および英国特許第１，４１３，７４８号に記載されている。
また単分散乳剤については、特開昭４８−８６００号、同５１−３９０２７号、同５１−８３０９７号、同５３−１３７１３３号、同５４−４８５２１号、同５４−９９４１９号、同５８−３７６３５号、同５８−４９９３８号、特公昭４７−１１３８６号、米国特許第３，６５５，３９４号および英国特許第１，４１３，７４８号などに記載されている。
【００６０】
ハロゲン化銀粒子のハロゲン組成の大部分あるいはごく一部分をハロゲン変換法によって変換させる方法は米国特許第３，４７７，８５２号、同４，１４２，９００号、欧州特許２７３，４２９号、同２７３，４３０号、西独公開特許第３，８１９，２４１号などに開示されており、有効な粒子形成法である。より難溶性の銀塩に変換するのに可溶性ハロゲンの溶液あるいはハロゲン化銀粒子を添加することができる。一度に変換する、複数回に分割して変換する、あるいは連続的に変換するなどの方法から選ぶことができる。
【００６１】
粒子成長を一定濃度、一定流速で可溶性銀塩とハロゲン塩を添加する方法以外に、英国特許第１，４６９，４８０号、米国特許第３，６５０，７５７号、同４，２４２，４５５号に記載されているように濃度を変化させる、あるいは流速を変化させる粒子形成法は好ましい方法である。濃度を増加させる、あるいは流速を増加させることにより、供給するハロゲン化銀量を添加時間の一次関数、二次関数、あるいはより複雑な関数で変化させることができる。
【００６２】
前述の平板状内部潜像型直接ポジハロゲン化銀乳剤と同様に、以上の乳剤調製時、例えば粒子形成時、脱塩工程、化学増感時、塗布前に金属イオンの塩を存在させることは目的に応じて好ましい。又、米国特許第３，７７２，０３１号に記載されているようなカルコゲナイド化合物を乳剤調製中に添加する方法も有効な場合がある。
【００６３】
本発明で用いる内部潜像型ハロゲン化銀粒子は前述したようにコア／シェル構造を有するものが好ましい。シェル製造方法、化学増感を施したコア粒子にシェルを被覆した後、粒子表面に化学増感を施す方法、更に化学増感補助剤の存在下に化学増感したり、還元増感もしくは、酸化剤を用いた増感法、等についても前述の平板状内部潜像型直接ポジハロゲン化銀乳剤と同様に行うことができる。
【００６４】
保護コロイドの選択、脱塩のための水洗法、増感色素を用いた分光増感法、感度低下や、かぶりの発生を防ぐ目的での、種々のカブリ防止剤、写真安定剤の使用、等についても前述の平板状内部潜像型直接ポジハロゲン化銀乳剤と同様に行うことができる。
【００６５】
（３）感光層の構成
減色法による天然色の再現には、上記分光増感色素により分光増感された乳剤と同波長範囲に選択的な分光吸収をもつ色素を供与する前記色素像形成物質とのくみあわせの少なくとも二つからなる感光層を用いる。乳剤と色素像形成物質とは別層として重ねて塗設してもよいし、また混合し一層として塗設してもよい。該色素像形成物質が塗布された状態で、これと組合わされた乳剤の分光感度域に吸収を持つ場合には別層の方が好ましい。また乳剤層は複数の、感度の異なる乳剤層からなるものでもよく、また乳剤層と色素像形成物質層との間に任意の層を設けてもよい。例えば、特開昭６０−１７３５４１号に記載された造核現像促進剤を含む層、特公昭６０−１５２６７号に記載された隔壁層を設けて色像濃度を高めたり、また反射層を設け感光要素の感度をたかめることも出来る。
反射層としては、白色顔料および親水性バインダーを含む層であり、好ましくは白色顔料は酸化チタン、親水性バインダーはゼラチンである。酸化チタンの塗布量は０．１ｇ／ｍ² 〜８ｇ／ｍ² 、好ましくは０．２ｇ／ｍ² 〜４ｇ／ｍ² である。反射層の例としては特開昭６０−９１３５４号に記載がある。
好ましい重層構成では、露光側から青感性乳剤の組合わせ単位、緑感性乳剤の組合わせ単位、赤感性乳剤の組合わせ単位が順次配置される。
各乳剤層単位の間には必要に応じて任意の層を設ける事ができる。特にある乳剤層の現像の効果が他の乳剤層単位に及ぼす好ましくない影響を防ぐため、混色防止層を設置するのが好ましい。
混色防止層は、非拡散性色素像形成物質と組合わせて現像薬を用いる場合には、該現像薬酸化体の拡散を防止するために非拡散性の還元剤を含むのが好ましい。具体的には非拡散性のハイドロキノン、スルホンアミドフェノール、スルホンアミドナフトールなどがあげられ、更に具体的には特公昭５０−２１２４９号、同５０−２３８１３号、特開昭４９−１０６３２９号、同４９−１２９５３５号、米国特許２，３３６，３２７号、同２，３６０，２９０号、同２，４０３，７２１号、同２，５４４，６４０号、同２，７３２，３００号、同２，７８２，６５９号、同２，９３７，０８６号、同３，６３７，３９３号、同３，７００，４５３号、英国特許５５７，７５０号、特開昭５７−２４９４１号、同５８−２１２４９号等に記載されている。これらの還元剤の乳剤層への好ましくない移動を防ぎ、還元剤としての活性を調節するためにポリマ−とともに分散して用いるのが好ましい。好ましいポリマ−としては、ポリビニル酢酸、ポリメチルメタクリレ−ト、ポリアクリルアミド誘導体等が挙げられる。それらの分散法については特開昭６０−２３８８３１号、特公昭６０−１８９７８号に記載されている。
特公昭５５−７５７６号に記載されたような銀イオンにより拡散性色素を放出する化合物を用いる場合には銀イオンを補足する化合物を混色防止層に含有せしめるのが好ましい。
本発明はその他必要に応じて、イラジエーション防止層、ＵＶ吸収剤層、保護層などが塗設される。
また必要に応じて、任意の隣接する層の間に、ゼラチンから成る隔壁層を設けることも出来る。
【００６６】
上記感光層の任意の層には、カブリを防ぎ、写真階調を調節するために、現像抑制剤プレカ−サ−、耐拡散性の還元剤等を組み込むことが出来る。
【００６７】
感光層に用いる親水性バインダ−としては、処理液の浸透と画像色素の転写が可能なものであれば、任意のものを用いられる。例えば、ゼラチン、ポリアクリルアミド、ポリビニルアルコ−ルあるいはそれらの誘導体などである。
親水性バインダ−は硬膜剤によって硬膜してもよく、親水性バインダ−の０．５％ないし５％、好ましくは０．５〜２％が添加される。
【００６８】
Ｆ）剥離層
本発明では必要に応じて処理後にユニット内感光シートの任意の場所で剥がし取る為に剥離層が設けることができる。
従ってこの剥離層は処理後の剥離が容易なものでなければならない。このための素材としては、例えば、特開昭４７−８２３７号、同５９−２２０７２７号、同５９−２２９５５５号、同４９−４６５３号、米国特許第３，２２０，８３５号、同４，３５９，５１８号、特開昭４９−４３３４号、同５６−６５１３３号、同４５−２４０７５号、米国特許第３，２２７，５５０号、同２，７５９，８２５号、同４，４０１，７４６号、同４，３６６，２２７号などに記載されたものを用いることができる。具体例の一つとしては、水溶性（あるいはアルカリ可溶性）のセルロース誘導体があげられる。例えばヒドロキシエチルセルロース、セルロースアセテートフタレート、可塑化メチルセルロース、エチルセルロース、硝酸セルロース、カルボキシメチルセルロース、などである。また別の例として種々の天然高分子、例えばアルギン酸、ペクチン、アラビアゴム、などがある。また種々の変性ゼラチン、例えばアセチル化ゼラチン、フタル化ゼラチンなども用いられる。更に、別の例として、水溶性の合成ポリマーがあげられる。例えば、ポリビニルアルコール、ポリアクリレート、ポリメチルメタクリレート、ポリブチルメタクリレート、あるいは、それらの共重合体などである。
剥離層は、単一の層でも、また例えば、特開昭５９−２２０７２７号、同６０−６０６４２号などに記載されているように複数の層からなるものでもよい。
【００６９】
II．カバーシート
本発明においては、感光要素上に処理液を均一に展開し、処理後のアルカリを中和し画像の安定化をはかるために、中和機能を有する層（中和層および中和タイミング層）を有する透明なカバーシートをもちいる。
【００７０】
Ｇ）支持体
本発明に用いられるカバーシートの支持体は写真感光材料に通常用いられる平滑な透明支持体なら、いずれでも用いられ、酢酸セルロース、ポリスチレン、ポリエチレンテレフタレート、ポリカーボネートなどが用いられ、下塗り層を設けるのが好ましい。
支持体には、ライトパイピングを防止するため微量の染料を含有させるのが好ましい。
【００７１】
Ｈ）中和機能を有する層
本発明に用いられる中和機能を有する層は、処理組成物から持込まれるアルカリを中和するに十分な量の酸性物質を含む層であり、必要に応じて、中和速度調節層（タイミング層）、密着強化層等の層から成る多層構成のものでもよい。好ましい酸性物質としてはｐＫａ９以下の酸性基（もしくは加水分解によってそのような酸性基を与える前駆体基）を含む物質であり、さらに好ましくは米国特許２，９８３，６０６号に記載されているオレイン酸のような高級脂肪酸、米国特許３，３６２，８１９号に開示されているようなアクリル酸、メタアクリル酸もしくはマレイン酸の重合体とその部分エステルまたは酸無水物；仏国特許２，２９０，６９９号に開示されているようなアクリル酸とアクリル酸エステルの共重体；米国特許４，１３９，３８３号やリサーチ・ディスクロージャ（Research Disclosure)Ｎｏ．１６１０２（１９７７）に開示されているようなラテックス型の酸性ポリマーを挙げることができる。
その他、米国特許４，０８８，４９３号、特開昭５２−１５３、７３９号、同５３−１、０２３号、同５３−４、５４０号、同５３−４、５４１号、同５３−４、５４２号等に開示の酸性物質も挙げることができる。
酸性ポリマーの具体例としてはエチレン、酢酸ビニル、ビニルメチルエーテル等のビニルモノマーと、無水マレイン酸との共重合体及びそのｎ−ブチルエステル、ブチルアクリレートとアクリル酸との共重合物、セルロース、アセテート・ハイドロジエンフタレート等である。
前記ポリマー酸は親水性ポリマーと混合して用いることができる。このようなポリマーとしては、ポリアクリルアミド、ポリメチルピロリドン、ポリビニルアルコール（部分ケン化物も含む）、カルボキシメチルセルロース、ヒドロキシメチルセルロース、ヒドロキシエチルセルロース、ポリメチルビニルエーテルなどである。なかでも、ポリビニルアルコールが好ましい。
また、前記ポリマー酸に親水性ポリマー以外のポリマー、例えばセルロースアセテートなどを混合してもよい。
ポリマー酸の塗布量は感光要素に展開されるアルカリの量により調節される。単位面積当りのポリマー酸とアルカリの当量比は０．９〜２．０が好ましい。ポリマー酸の量が少なすぎると、転写色素の色相が変化したり、白地部分にステインを生じ、又多過ぎる場合にも色相の変化、あるいは耐光性の低下などの不都合を生じる。更に好ましい当量比は１．０〜１．３である。混合する親水性ポリマーの量も多すぎても少なすぎても写真の品質を低下させる。親水性ポリマーのポリマー酸にたいする重量比は０．１〜１０、好ましくは０．３〜３．０である。
本発明の中和機能を有する層には、種々の目的で添加剤を組込むことが出来る。たとえば、この層の硬膜を行うために当業者で周知の硬膜剤、また膜の脆性を改良するためにポリエチレングリコール、ポリプロピレングリコール、グリセリンなどの多価ヒドロキシル化合物を添加することができる。その他必要に応じて、酸化防止剤、蛍光増白剤、現像抑制剤およびその前駆体などを添加することもできる。
中和層と組合わせて用いるタイミング層は例えばゼラチン、ポリビニルアルコール、ポリビニルアルコールの部分アセタール化物、酢酸セルロース、部分的に加水分解されたポリ酢酸ビニル、などのようなアルカリ透過性を低くするポリマー；アクリル酸モノマーなどの親水性コモノマーを少量共重合させてつくられた、アルカリ透過の活性化エネルギーを高くするラテックスポリマー；ラクトン環を有するポリマーなどが有用である。
なかでも、特開昭５４−１３６３２８号、米国特許４，２６７，２６２号、同４，００９，０３０号、同４，０２９，８４９号等に開示されている酢酸セルロースを使用したタイミング層；特開昭５４−１２８３３５号、同５６−６９、６２９号、同５７−６、８４３号、米国特許４，０５６，３９４号、同４，０６１，４９６号、同４，１９９，３６２号、同４，２５０，２４３号、同４，２５６，８２７号、同４，２６８，６０４号等に開示されている、アクリル酸などの親水性コモノマーを少量共重合させてつくられたラテックスポリマー；米国特許４，２２９，５１６号に開示されたラクトン環を有するポリマー；その他特開昭５６−２５７３５号、同５６−９７３４６号、同５７−６８４２号、ヨーロッパ特許（ＥＰ）３１，９５７Ａ１号、同３７，７２４Ａ１号、同４８，４１２Ａ１号などに開示されたポリマーが特に有用である。
その他、以下の文献に記載のものも使用できる。
米国特許３，４２１，８９３号、同３，４５５，６８６号、同３，５７５，７０１号、同３，７７８，２６５号、同３，７８５，８１５号、同３，８４７，６１５号、同４，０８８，４９３号、同４，１２３，２７５号、同４，１４８，６５３号、同４，２０１，５８７号、同４，２８８，５２３号、同４，２９７，４３１号、西独特許出願（ＯＬＳ）１，６２２，９３６号、同２，１６２，２７７号、Research Disclosure １５１６２, Ｎｏ. １５１（１９７６年）。
これらの素材を用いたタイミング層は単独層もしくは二種以上の層の併用として使用しうる。
またこれらの素材からなるタイミング層に、例えば米国特許４，００９，０２９号、西独特許出願（ＯＬＳ）２，９１３，１６４号、同３，０１４，６７２号、特開昭５４−１５５８３７号、同５５−１３８７４５号、などに開示された現像抑制剤および／もしくはそのプレカーサーや、また、米国特許４，２０１，５７８号に開示されているハイドロキノンプレカーサー、その他有用な写真用添加剤もしくはそのプレカーサーなどを組み込むことも可能である。
さらには、中和機能を有する層として、特開昭６３−１６８６４８号、同６３−１６８６４９号に記載の如く補助中和層を設けることが処理後経時による転写濃度の変化を少なくするという点において効果がある。
【００７２】
Ｉ）その他
中和機能を有する層の他に、補助的な機能を持つ層として、バック層、保護層、フィルター染料層などを有しても良い。
バック層は、カールの調整や、滑り性の付与の為に設けられる。フィルター染料はこの層に添加しても良い。
保護層は、モノシ−ト型感光材料においては、主としてカバーシートバック面との接着、感光材料とカバーシートとを重ね合わせたときの感光材料保護層との接着を防止する為に用いられる。
捕獲媒染層は、アルカリ処理組成物側に拡散した色素を捕獲する事により、画像完成時間の遅れや先鋭度の劣化を防止する事が出来る。通常、カバーシートの最外層に色素捕獲層を設ける。色素捕獲層は、前述の染料受像層と同様に親水性コロイド中にポリマー媒染剤を含むものであり、特開平１−１９８７４７号、特開平２−２８２２５３号に記載されている。
カバーシートに染料を含有させて感光層の感度調整を行う事もできる。フィルター染料は、直接カバーシートの支持体中や中和機能を有する層、さらには前記のバック層、保護層、捕獲媒染層などに添加しても良いし、単独の層を設置しても良い。
【００７３】
III. アルカリ処理組成物
本発明に用いられる処理組成物は、感光要素の露光後に感光要素上に均一に展開され、その含有する成分によって感光層の現像を行うものである。このために、組成物中には、アルカリ、増粘剤、現像薬、更に、現像を調節するための、現像促進剤、現像抑制剤、現像薬の劣化を防ぐための酸化防止剤、階調調節剤、などを含有する。
アルカリは液のｐＨを１２〜１４とするに足りるものであり、アルカリ金属の水酸化物（例えば水酸化ナトリウム、水酸化カリウム、水酸化リチウム）、アルカリ金属のリン酸塩（例えばリン酸カリウム）、グアニジン類、四級アミンの水酸化物（例えば水酸化テトラメチルアンモニウムなど）が挙げられるが、なかでも水酸化カリウム、水酸化ナトリウムが好ましく、特に水酸化カリウムが好ましい。
増粘剤は処理液を均一に展開するために、また感光層／カバーシート間の密着を保つために必要である。例えば、ポリビニルアルコール、ヒドロキシエチルセルロース、カルボキシメチルセルロースのアルカリ金属塩が用いられるが、処理液の破裂可能容器からの液もれを防ぎ、かつ展開時には均一に感光層上に展開されるよう、チクソトロピー性のものが好ましく、このためヒドロキシエチルセルロース、ヒドロキシメチルカルボン酸ナトリウム、カルボキシメチル−ヒドロキシエチルセルロースが用いられる。
【００７４】
好ましい現像薬は、色素像形成物質をクロス酸化し、かつ酸化されても実質的にステインを生じないものであればどのようなものでも使用出来る。このような現像薬は単独でもまた二種類以上を併用してもよく、またプレカーサーの型で使用してもよい。これらの現像薬は感光要素の適当な層に含ませても、またアルカリ性処理液中に含ませてもよい。具体的化合物としてはアミノフェノール類、ピラゾリジノン類があげられるが、このうちピラゾリジノン類がステインの発生が少ないため特に好ましい。
たとえば１−フェニル−３−ピラゾリジノン、１−ｐ−トリル−４，４−ジヒドロキシメチル−３−ピラゾリジノン、１−（３′−メチル−フェニル）−４−メチル−４−ヒドロキシメチル−３−ピラゾリジノン、１−フェニル−４−メチル−４−ヒドロキシメチル−３−ピラゾリジノン、１−ｐ−トリル−４−メチル−４−ヒドロキシメチル−３−ピラゾリジノン、などが挙げられる。
【００７５】
現像促進剤としては、アミン、アミノ酸、ポリエチレングリコール類の他、ベンジルアルコール、ジヒドロキシメチルベンゼン等が用いられる。
現像抑制剤としては、任意のものを用いることができるが、造核剤と組み合わされたオートポジ乳剤の現像にはトリアゾール誘導体が好ましく、特にベンズトリアゾールの誘導体が好ましい。
現像薬の劣化を防ぐ酸化防止剤としては、現像薬の酸化を防止するにたりる還元力を有する任意のものが用いられるが、亜硫酸塩、特に亜硫酸カリウムが好ましく用いられる。
階調調節剤としては、ハイドロキノン誘導体、アスコルビン酸誘導体が好ましく用いられる。
その他、処理液の経時安定性を高めるために、遷移金属塩、例えば硝酸亜鉛等を添加したり、ｐＨ緩衝性を付与するためにアルミニウム塩を添加するのも好ましい。
【００７６】
処理液には必要に応じて遮光剤を含ませることが出来る。特に、透明支持体を通して露光する一体型感光材料の場合には、処理液に遮光性を付与することが必要である。
そのための遮光剤としては、カ−ボンブラックその他の顔料、染料を用いることが出来る。特に処理液に白色顔料を含み、展開された処理液層を背景に色素画像を観察する場合には、遮光剤としてｐＨ感応性の色素を用いることが好ましい。
【００７７】
感光シート、カバーシートあるいはアルカリ処理組成物のいずれかに特開昭６２−２１５２７２号７２〜９１頁記載の現像促進剤、１４６〜１５５頁記載の硬膜剤、２０１〜２１０頁記載の界面活性剤、２１０〜２２２頁記載の含フッ素化合物、２２５〜２２７頁記載の増粘剤、２２７〜２３０頁記載の帯電防止剤、２３０〜２３９頁記載のポリマーラテックス、２４０頁記載のマット剤などを含む事ができる。
【００７８】
【実施例】
以下、本発明を実施例によって具体的に説明するが、本発明はこれに限定されない。
実施例−１
まず、ハロゲン化銀乳剤の調製法について説明する。
以下に示す乳剤粒子の調製法により、８種類のハロゲン化銀乳剤粒子［乳剤−Ａ−１、乳剤−Ｂ、乳剤−Ｃおよび金属塩の添加部位と添加量の異なる乳剤Ｄ−１〜Ｄ−５（第１表を参照）］を調製した。
【００７９】
【表１】

【００８０】
乳剤−Ａ−１（八面体内部潜像型直接ポジ乳剤）の調製：（比較用）
臭化カリウム０．０５Ｍ、３，６−ジチア−１，８−オクタンジオール１ｇ、酢酸鉛０．０３４mg及びＣａ含量１００ｐｐｍ以下の脱イオンゼラチン６０ｇを含有するゼラチン水溶液１０００ml中に、温度を７５℃に保ちながら０．４Ｍの硝酸銀水溶液と０．４Ｍの臭化カリウム水溶液をコントロールダブルジェット法でｐＢｒが１．６０になるように臭化カリウム水溶液の添加速度を調節しながら、硝酸銀水溶液３００mlを４０分間かけて添加した。
添加が終了すると、平均粒径（球相当径）が約０．７μの粒子サイズの揃った八面体臭化銀結晶（以後コア粒子と呼ぶ）が生成された。
次に、この調製液にチオ硫酸ナトリウム１mg、四塩化金酸カリウム９０mg及び酢酸鉛４．１mgと臭化カリウム１．２ｇを水１０００mlに溶解した水溶液３mlを加え、７５℃で８０分間加熱することにより化学増感処理を行った。このようにして化学増感を施した乳剤溶液に０．１５Ｍの臭化カリウムを添加した後、コア粒子調製時と同様に、温度を７５℃に保ちながら０．９Ｍの硝酸銀水溶液と０．９Ｍの臭化カリウム水溶液をコントロールダブルジェット法でｐＢｒが１．３０になるように臭化カリウム水溶液の添加速度を調節しながら、硝酸銀水溶液６７０mlを７０分間かけて添加した。
この乳剤を常法のフロキュレーション法により水洗し、前述のゼラチン及び２−フェノキシエタノール、Ｐ−ヒドロキシ安息香酸メチルを添加して平均粒径（球相当径）が約１．４μの粒子サイズの揃った八面体臭化銀結晶（以後内部潜像型コア／シェル粒子と呼ぶ）を得た。
次に、この内部潜像型コア／シェル乳剤にチオ硫酸ナトリウム１００mgと四硼酸ナトリウム４０mgを水１０００mlに溶解した水溶液３mlを加え、更に１４mgのポリ（Ｎ−ビニルピロリドン）を加え、６０℃で加熱熟成した後、０．００５Ｍの臭化カリウムを添加することにより、八面体内部潜像型直接ポジ乳剤を調製した。
【００８１】
乳剤−Ｂ（八面体内部潜像型直接ポジ乳剤）の調製：
乳剤−Ａの調整法に於いて、硝酸銀水溶液及び臭化カリウム水溶液の添加時間を変更し、更に添加薬品量の変更を行って、平均粒径（球相当径）が約１．０μの粒子サイズの揃った八面体内部潜像型直接ポジ乳剤を得た。
【００８２】
乳剤−Ｃ（八面体内部潜像型直接ポジ乳剤）の調製：
乳剤−Ａの調整法に於いて、硝酸銀水溶液及び臭化カリウム水溶液の添加時間を変更し、更に添加薬品量の変更を行って、平均粒径（球相当径）が約０．７μの粒子サイズの揃った八面体内部潜像型直接ポジ乳剤を得た。
【００８３】
乳剤−Ｄ−１（六角平板状内部潜像型直接ポジ乳剤）調製：（比較用）
臭化カリウム０．０５Ｍ、平均分子量が１０万以下のゼラチンを０．７重量％含むゼラチン水溶液１．２リットル中に、前述のゼラチンを含んだ１．４Ｍの硝酸銀水溶液と２Ｍの臭化カリウム水溶液を激しく攪拌しながらダブルジェット法で１分間で各３３mlを同時に混合した。この間ゼラチン水溶液は３０℃に保たれた。更に、Ｃａ含量１００ｐｐｍ以下の脱イオンゼラチンを１０重量％含むゼラチン溶液３００mlを添加した後７５℃に昇温した。
次に０．９Ｍの硝酸銀水溶液４０mlを３分間かけて添加した後、２５重量％のアンモニア水溶液を添加し、７５℃で熟成を行った。熟成終了後、アンモニアを中和した後１Ｍの硝酸銀水溶液と１Ｍの臭化カリウム水溶液をｐＢｒを２．５にたもちながら加速された流速（終了時の流速が開始時の流速の６倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は５００mlであった。）
このようにして形成した粒子（以後コア粒子と呼ぶ）を常法のフロキュレーション法により水洗し、ゼラチン及び２−フェノキシエタノール、Ｐ−ヒドロキシ安息香酸メチルを添加して７５０ｇの六角平板状コア粒子を得た。
得られた六角平板状コア粒子は平均投影面積円相当直径が０．９μｍ、平均の厚みは０．２０μｍであり、全投影面積の９５％が六角平板粒子によって占められていた。
次に、前記六角平板状コア乳剤２００ｇに水１３００cc、臭化カリウム０．１１Ｍと脱イオンゼラチン４０ｇを添加し、７５℃に昇温した後、３，６−ジチア−１，８−オクタンジオール０．３ｇ、ベンゼンチオ硫酸ナトリウム１０mg、及び四塩化金酸カリウム９０mgと臭化カリウム１．２ｇを水１０００mlに溶解した水溶液２．４mlを加え、７５℃で１８０分間加熱することにより化学増感処理を行った。このようにして化学増感を施したコア粒子にコア粒子調製時と同様に、２Ｍの硝酸銀水溶液と２．５Ｍの臭化カリウム水溶液をｐＢｒが２．５になるように臭化カリウム水溶液の添加量及び添加速度を調節しながら、加速された流速（終了時の流速が開始時の流速の３倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は８１０mlであった。）
０．３Ｍの臭化カリウムを添加した後、この乳剤を常法のフロキュレーション法により水洗し、ゼラチンを添加した。このようにして六角平板状内部潜像型コア／シェル乳剤を得た。得られた六角平板状粒子は平均投影面積円相当直径が２．５μｍ、平均の厚さが０．３７μｍ、平均体積サイズが１．４（μｍ)³で全投影面積の８８％が六角平板状粒子によって占められていた。
次に、この六角平板状内部潜像型コア／シェル乳剤にチオ硫酸ナトリウム１００mgと四硼酸ナトリウム４０mgを水１０００mlに溶解した水溶液１５mlを加え、更に２０mgのポリ（Ｎ−ビニルピロリドン）を加え、６０℃で１００分間加熱することにより粒子表面の化学増感を行い、六角平板状内部潜像型直接ポジ乳剤Ｄ−１を調製した。
【００８４】
乳剤−Ｄ−２（六角平板状内部潜像型直接ポジ乳剤）調製：（比較用）
臭化カリウム０．０５Ｍ、平均分子量が１０万以下のゼラチンを０．７重量％含むゼラチン水溶液１．２リットル中に、前述のゼラチンを含んだ１．４Ｍの硝酸銀水溶液と２Ｍの臭化カリウム水溶液を激しく攪拌しながらダブルジェット法で１分間で各３３mlを同時に混合した。この間ゼラチン水溶液は３０℃に保たれた。更に、Ｃａ含量１００ｐｐｍ以下の脱イオンゼラチンを１０重量％含むゼラチン溶液３００mlを添加した後７５℃に昇温した。
次に０．９Ｍの硝酸銀水溶液４０mlを３分間かけて添加した後、２５重量％のアンモニア水溶液を添加し、７５℃で熟成を行った。熟成終了後、アンモニアを中和した後、１Ｍの硝酸銀水溶液と１Ｍの臭化カリウム水溶液をｐＢｒを２．５にたもちながら加速された流速（終了時の流速が開始時の流速の６倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は５００mlであった。）
このようにして形成した粒子（以後コア粒子と呼ぶ）を常法のフロキュレーション法により水洗し、ゼラチン及び２−フェノキシエタノール、Ｐ−ヒドロキシ安息香酸メチルを添加して７５０ｇの六角平板状コア粒子を得た。
得られた六角平板状コア粒子は平均投影面積円相当直径が０．９μｍ、平均の厚みは０．２０μｍであり、全投影面積の９５％が六角平板粒子によって占められていた。
次に、前記六角平板状コア乳剤２００ｇに水１３００ml、臭化カリウム０．１１Ｍと脱イオンゼラチン４０ｇを添加し、７５℃に昇温した後、３，６−ジチア−１，８−オクタンジオール０．３ｇ、ベンゼンチオ硫酸ナトリウム１０mg、及び四塩化金酸カリウム９０mgと臭化カリウム１．２ｇを水１０００mgに溶解した水溶液２．４cc、及び酢酸鉛１５mg（水溶液にて添加）を加え、７５℃で１８０分間加熱することにより化学増感処理を行った。このようにして化学増感を施したコア粒子にコア粒子調製時と同様に、２Ｍの硝酸銀水溶液と２．５Ｍの臭化カリウム水溶液をｐＢｒが２．５になるように臭化カリウム水溶液の添加速度を調節しながら、加速された流速（終了時の流速が開始時の流速の３倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は８１０mlであった。）
０．３Ｍの臭化カリウムを添加した後、この乳剤を常法のフロキュレーション法により水洗し、ゼラチンを添加した。このようにして六角平板状内部潜像型コア／シェル乳剤を得た。得られた六角平板状粒子は平均投影面積円相当直径が２．５μｍ、平均の厚さが０．３７μｍ、平均体積サイズが１．４（μｍ)³で全投影面積の８８％が六角平板状粒子によって占められていた。
次に、この六角平板状内部潜像型コア／シェル乳剤にチオ硫酸ナトリウム１００mgと四硼酸ナトリウム４０mgを水１０００mlに溶解した水溶液１５mlを加え、更に２０mgのポリ（Ｎ−ビニルピロリドン）を加え、６０℃で１００分間加熱することにより粒子表面の化学増感を行い、六角平板状内部潜像型直接ポジ乳剤Ｄ−２を調製した。
【００８５】
乳剤−Ｄ−３（六角平板状内部潜像型直接ポジ乳剤）調製：（本発明）
臭化カリウム０．０５Ｍ、平均分子量が１０万以下のゼラチンを０．７重量％含むゼラチン水溶液１．２リットル中に、前述のゼラチンを含んだ１．４Ｍの硝酸銀水溶液と２Ｍの臭化カリウム水溶液を激しく攪拌しながらダブルジェット法で１分間で各３３mlを同時に混合した。この間ゼラチン水溶液は３０℃に保たれた。更に、Ｃａ含量１００ｐｐｍ以下の脱イオンゼラチンを１０重量％含むゼラチン溶液３００mlを添加した後７５℃に昇温した。
次に０．９Ｍの硝酸銀水溶液４０mlを３分間かけて添加した後、２５重量％のアンモニア水溶液を添加し、７５℃で熟成を行った。熟成終了後、アンモニアを中和した後酢酸鉛５mg（水溶液にて添加）を加え、１Ｍの硝酸銀水溶液と１Ｍの臭化カリウム水溶液をｐＢｒを２．５にたもちながら加速された流速（終了時の流速が開始時の流速の６倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は５００mlであった。）
このようにして形成した粒子（以後コア粒子と呼ぶ）を常法のフロキュレーション法により水洗し、ゼラチン及び２−フェノキシエタノール、Ｐ−ヒドロキシ安息香酸メチルを添加して７５０ｇの六角平板状コア粒子を得た。
得られた六角平板状コア粒子は平均投影面積円相当直径が０．９μｍ、平均の厚みは０．２０μｍであり、全投影面積の９５％が六角平板粒子によって占められていた。
次に、前記六角平板状コア乳剤２００ｇに水１３００ml、臭化カリウム０．１１Ｍと脱イオンゼラチン４０ｇを添加し、７５℃に昇温した後、３，６−ジチア−１，８−オクタンジオール０．３ｇ、ベンゼンチオ硫酸ナトリウム１０mg、及び四塩化金酸カリウム９０mgと臭化カリウム１．２ｇを水１０００mlに溶解した水溶液２．４ml、及び酢酸鉛１５mg（水溶液にて添加）を加え、７５℃で１８０分間加熱することにより化学増感処理を行った。このようにして化学増感を施したコア粒子にコア粒子調製時と同様に、２Ｍの硝酸銀水溶液と２．５Ｍの臭化カリウム水溶液をｐＢｒが２．５になるように臭化カリウム水溶液の添加速度を調節しながら、加速された流速（終了時の流速が開始時の流速の３倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は８１０mlであった。）
０．３Ｍの臭化カリウムを添加した後、この乳剤を常法のフロキュレーション法により水洗し、ゼラチンを添加した。このようにして六角平板状内部潜像型コア／シェル乳剤を得た。得られた六角平板状粒子は平均投影面積円相当直径が２．５μｍ、平均の厚さが０．３７μｍ、平均体積サイズが１．４（μｍ)³で全投影面積の８８％が六角平板状粒子によって占められていた。
次に、この六角平板状内部潜像型コア／シェル乳剤にチオ硫酸ナトリウム１００mgと四硼酸ナトリウム４０mgを水１０００mlに溶解した水溶液１５mlを加え、更に２０mgのポリ（Ｎ−ビニルピロリドン）を加え、６０℃で１００分間加熱することにより粒子表面の化学増感を行い、六角平板状内部潜像型直接ポジ乳剤Ｄ−３を調製した。
【００８６】
乳剤−Ｄ−４（六角平板状内部潜像型直接ポジ乳剤）調製：（本発明）
臭化カリウム０．０５Ｍ、平均分子量が１０万以下のゼラチンを０．７重量％含むゼラチン水溶液１．２リットル中に、前述のゼラチンを含んだ１．４Ｍの硝酸銀水溶液と２Ｍの臭化カリウム水溶液を激しく攪拌しながらダブルジェット法で１分間で各３３mlを同時に混合した。この間ゼラチン水溶液は３０℃に保たれた。更に、Ｃａ含量１００ｐｐｍ以下の脱イオンゼラチンを１０重量％含むゼラチン溶液３００mlを添加した後７５℃に昇温した。
次に０．９Ｍの硝酸銀水溶液４０mlを３分間かけて添加した後、２５重量％のアンモニア水溶液を添加し、７５℃で熟成を行った。熟成終了後、アンモニアを中和した後酢酸鉛５００mg（水溶液にて添加）を加え、１Ｍの硝酸銀水溶液と１Ｍの臭化カリウム水溶液をｐＢｒを２．５にたもちながら加速された流速（終了時の流速が開始時の流速の６倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は５００mlであった。）
このようにして形成した粒子（以後コア粒子と呼ぶ）を常法のフロキュレーション法により水洗し、ゼラチン及び２−フェノキシエタノール、Ｐ−ヒドロキシ安息香酸メチルを添加して７５０ｇの六角平板状コア粒子を得た。
得られた六角平板状コア粒子は平均投影面積円相当直径が０．９μｍ、平均の厚みは０．２０μｍであり、全投影面積の９５％が六角平板粒子によって占められていた。
次に、前記六角平板状コア乳剤２００ｇに水１３００ml、臭化カリウム０．１１Ｍと脱イオンゼラチン４０ｇを添加し、７５℃に昇温した後、３，６−ジチア−１，８−オクタンジオール０．３ｇ、ベンゼンチオ硫酸ナトリウム１０mg、及び四塩化金酸カリウム９０mgと臭化カリウム１．２ｇを水１０００mlに溶解した水溶液２．４ml、及び酢酸鉛１５０mg（水溶液にて添加）を加え、７５℃で１８０分間加熱することにより化学増感処理を行った。このようにして化学増感を施したコア粒子にコア粒子調製時と同様に、２Ｍの硝酸銀水溶液と２．５Ｍの臭化カリウム水溶液をｐＢｒが２．５になるように臭化カリウム水溶液の添加速度を調節しながら、加速された流速（終了時の流速が開始時の流速の３倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は８１０mlであった。）
０．３Ｍの臭化カリウムを添加した後、この乳剤を常法のフロキュレーション法により水洗し、ゼラチンを添加した。このようにして六角平板状内部潜像型コア／シェル乳剤を得た。得られた六角平板状粒子は平均投影面積円相当直径が２．５μｍ、平均の厚さが０．３７μｍ、平均体積サイズが１．４（μｍ)³で全投影面積の８８％が六角平板状粒子によって占められていた。
次に、この六角平板状内部潜像型コア／シェル乳剤にチオ硫酸ナトリウム１００mgと四硼酸ナトリウム４０mgを水１０００mlに溶解した水溶液１５mlを加え、更に２０mgのポリ（Ｎ−ビニルピロリドン）を加え、６０℃で１００分間加熱することにより粒子表面の化学増感を行い、六角平板状内部潜像型直接ポジ乳剤Ｄ−４を調製した。
【００８７】
乳剤−Ｄ−５（六角平板状内部潜像型直接ポジ乳剤）調製：（本発明）
臭化カリウム０．０５Ｍ、平均分子量が１０万以下のゼラチンを０．７重量％含むゼラチン水溶液１．２リットル中に、前述のゼラチンを含んだ１．４Ｍの硝酸銀水溶液と２Ｍの臭化カリウム水溶液を激しく攪拌しながらダブルジェット法で１分間で各３３mlを同時に混合した。この間ゼラチン水溶液は３０℃に保たれた。更に、Ｃａ含量１００ｐｐｍ以下の脱イオンゼラチンを１０重量％含むゼラチン溶液３００mlを添加した後７５℃に昇温した。
次に０．９Ｍの硝酸銀水溶液４０mlを３分間かけて添加した後、２５重量％のアンモニア水溶液を添加し、７５℃で熟成を行った。熟成終了後、アンモニアを中和した後硝酸カドミウム３．６mg（水溶液にて添加）を加え、１Ｍの硝酸銀水溶液と１Ｍの臭化カリウム水溶液をｐＢｒを２．５にたもちながら加速された流速（終了時の流速が開始時の流速の６倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は５００mlであった。）
このようにして形成した粒子（以後コア粒子と呼ぶ）を常法のフロキュレーション法により水洗し、ゼラチン及び２−フェノキシエタノール、Ｐ−ヒドロキシ安息香酸メチルを添加して７５０ｇの六角平板状コア粒子を得た。
得られた六角平板状コア粒子は平均投影面積円相当直径が０．９μｍ、平均の厚みは０．２０μｍであり、全投影面積の９５％が六角平板粒子によって占められていた。
次に、前記六角平板状コア乳剤２００ｇに水１３００ml、臭化カリウム０．１１Ｍと脱イオンゼラチン４０ｇを添加し、７５℃に昇温した後、３，６−ジチア−１，８−オクタンジオール０．３ｇ、ベンゼンチオ硫酸ナトリウム１０mg、及び四塩化金酸カリウム９０mgと臭化カリウム１．２ｇを水１０００mlに溶解した水溶液２．４ml、及び硝酸カドミウム１１mg（水溶液にて添加）を加え、７５℃で１８０分間加熱することにより化学増感処理を行った。このようにして化学増感を施したコア粒子にコア粒子調製時と同様に、２Ｍの硝酸銀水溶液と２．５Ｍの臭化カリウム水溶液をｐＢｒが２．５になるように臭化カリウム水溶液の添加速度を調節しながら、加速された流速（終了時の流速が開始時の流速の３倍）でダブルジェット法で添加した。（使用した硝酸銀水溶液の量は８１０mlであった。）
０．３Ｍの臭化カリウムを添加した後、この乳剤を常法のフロキュレーション法により水洗し、ゼラチンを添加した。このようにして六角平板状内部潜像型コア／シェル乳剤を得た。得られた六角平板状粒子は平均投影面積円相当直径が２．５μｍ、平均の厚さが０．３７μｍ、平均体積サイズが１．４（μｍ)³で全投影面積の８８％が六角平板状粒子によって占められていた。
次に、この六角平板状内部潜像型コア／シェル乳剤にチオ硫酸ナトリウム１００mgと四硼酸ナトリウム４０mgを水１０００mlに溶解した水溶液１５mlを加え、更に２０mgのポリ（Ｎ−ビニルピロリドン）を加え、６０℃で１００分間加熱することにより粒子表面の化学増感を行い、六角平板状内部潜像型直接ポジ乳剤Ｄ−５を調製した。
【００８８】
これらの乳剤を使用して、第２表の構成を有する比較用感光要素（試料１０１）を作成した。
【００８９】
【表２】

【００９０】
【表３】

【００９１】
【表４】

【００９２】
【表５】

【００９３】
【表６】

【００９４】
【表７】

【００９５】
【表８】

【００９６】
【化４】

【００９７】
【化５】

【００９８】
【化６】

【００９９】
【化７】

【０１００】
【化８】

【０１０１】
【化９】

【０１０２】
カバーシートは以下のようにして作成した。
ゼラチン下塗りしたライトパイピング防止染料を含むポリエチレンテレフタレート透明支持体上に以下の層を塗設した。
(1) 平均分子量５万のアクリル酸−ブチルアクリレート（モル比８：２）共重合体を１０．４ｇ／m²および１，４−ビス（２，３−エポキシプロポキシ）−ブタン０．１ｇ／m²を含む中和層。
(2) 酸化度５１％のアセチルセルロース４．３ｇ／m²、ポリ（メチルビニルエーテル−コ−モノメチルマレエイド）０．２ｇ／m²を含む中和タイミング層。
(3) スチレン−ブチルアクリレート−アクリル酸−Ｎメチロールアクリルアミドを重量比４９．７／４２．３／４／４の比で乳化重合したポリマーラテックスと、メチルメタクリレート／アクリル酸／Ｎ−メチロールアクリルアミドを重量比９３対３対４の比で乳化重合したポリマーラテックスを固型分比が６対４になるようにブレンドし、総固型分を２．５ｇ／m²含む層。
(4) ゼラチン１ｇ／m²を含む層。
【０１０３】
アルカリ処理組成物は以下の方法で調製した。
下記組成の処理液０．８ｇを圧力で破壊可能な容器に充填した。
１−ｐ−トリル−４−ヒドロキシメチル−４−メチル
−３−ピラゾリドン １０．０ｇ
メチルハイドロキノン ０．１８ｇ
５−メチルベンゾトリアゾール ３．０ｇ
亜硫酸ナトリウム（無水） ０．２ｇ
ベンジルアルコール １．５ml
カルボキシメチルセルロースＮａ塩 ５８ｇ
カーボンブラック １５０ｇ
水酸化カリウム（２８％水溶液） ２００ml
水 ６８０ml
【０１０４】
次に、第８層、第１５層、第２２層の乳剤を第１表に示す乳剤Ｄ−２，Ｄ−３，Ｄ−４，Ｄ−５，Ａ−１に変更して、第３表に示す試料１０２、１０３、１０４、１０５、２０１を作成した。
【０１０５】
【表９】

【０１０６】
前記感光要素１０１〜１０５、２０１を次のＡ，Ｂ，Ｃ，３つの保存条件
保存条件Ａ：冷凍３日
保存条件Ｂ：５０℃・３０％・３日
保存条件Ｃ：４５℃・７０％・３日
で保存した後、グレーの連続ウエッジを通して乳剤層側から露光したのち、前記カバーシートと重ね合わせ、両材料の間に上記処理液を７５μｍの厚みになるように加圧ローラーを使用して展開した。露光は露光量が一定になるように露光照度を調節して行なった。処理は２５℃で行ない、１０分後に転写濃度をカラー濃度計で測定した。その結果を第４表に示す。但しここに示す中点感度とは最大濃度と最低濃度の中間濃度を与える露光量の逆数値を基準試料に対して相対値で表わした。また、低濃度感度とは最低濃度＋０．２に対応する濃度を与える露光量の逆数値を基準試料に対して相対値で表わした。
【０１０７】
【表１０】

【０１０８】
第４表より本発明の試料１０３、１０４、１０５は比較試料１０１、１０２、２０１に比して中点感度、低濃度感度ともに高くかつ高湿保存下における最大濃度の低下は小さく、低湿保存下での減感も小さいことが分かる。
【０１０９】
【発明の効果】
本発明によって高感度でかつ保存性に優れた画像が得られることが分かった。[0001]
[Industrial application fields]
The present invention relates to an internal latent image type direct positive silver halide emulsion and a color diffusion transfer photosensitive material using the same.
[0002]
[Prior art]
A photographic method using silver halide is superior in sensitivity and gradation characteristics as compared with other photographic methods such as electrophotographic method and diazo photographic method, and has been widely used conventionally. Among these, a method for directly forming a positive image is known. For example, as disclosed in U.S. Pat. No. 3,761,276 and JP-B-60-55821, an internal latent image type direct positive silver halide photographic emulsion is used to form a halogen having an internal latent image formed thereon. When developing silver halide grains with a surface developer (a developer that leaves the latent image formation sites inside the silver halide grains substantially undeveloped), a positive image is obtained by giving uniform exposure or using a nucleating agent. To get.
[0003]
Regarding tabular silver halide grains, “Theory and Practice of Photography” by Cleve (Cleve, Photography Theory and Practice (1930)), p. 131; Gatoff, Photographic Science and Engineering (Gutoff, Photographic Science) 14), 248-257 (1970); U.S. Pat. Nos. 4,434,226, 4,414,310, 4,433,048, 4,439,520. No. 4,414,306, No. 4,459,353, British Patent No. 2,112,157, JP-A Nos. 59-99433, 62-209445, etc. disclose their production methods and use techniques. ing. In particular, regarding the tabular internal latent image type direct positive silver halide emulsion, U.S. Pat. Nos. 4,395,478 and 4,504,570, 4,996,137, JP-B 64-8327, This is described in detail in JP-A-1-131547. These tabular internal latent image type direct positive emulsions are excellent in that they provide a direct positive image having good sharpness, rapid development progress and small development temperature dependency.
[0004]
US Pat. No. 2,448,060 describes that a silver halide emulsion can be sensitized by adding a transition metal compound at several stages in the production of a silver halide emulsion. It is known that there is a marked difference in the photographic effect of transition metal compounds in silver halide emulsions when transition metal compounds are added during the formation of silver halide grains and when they are added after silver halide grain precipitation. Yes. The former case is particularly called a metal dopant. These are described in Research Disclosure, Volume 176 (issued December 1978) item 17643.
[0005]
In the internal latent image type direct positive silver halide photographic emulsion, it is known that the low density portion on the reversal characteristic curve becomes hardened by doping metal ions. For example, U.S. Pat. Nos. 3,271,157, 3,367,778, 3,447,927, 3,531,291, 3,761,267, and 3,761. 276, 3,850,637, 3,923,513, 4,035,185, 4,444,874, 4,444,865, 4,433,047 No. 4,395,478, British Patent No. 1,151,782, No. 1,529,011, and the like. However, it has been known that the maximum concentration on the inversion characteristic curve is lowered by doping a large amount of metal ions.
[0006]
On the other hand, U.S. Pat. No. 4,395,478 discloses a monovalent or polyvalent cation (Mn, Cu, Zn, Cd, Pb, Bi) in the shell portion of an internal latent image type core / shell direct positive silver halide photographic emulsion. , Lanthanide), the re-inversion negative image is reduced, the minimum density is lowered, and the sensitivity is increased. However, the same effect was obtained by applying these techniques to a tabular internal latent image type direct positive emulsion, but the storage stability was not sufficiently satisfactory, and the maximum density was lowered particularly under high humidity storage. It has been found that there is a drawback of desensitization under low humidity storage.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide a tabular internal latent image type core / shell direct positive silver halide photographic emulsion having high sensitivity and excellent storage stability, and a color diffusion transfer photosensitive material using the same.
[0008]
[Means for Solving the Problems]
The object of the present invention is as follows (1), (2), (3), (4 )of This was achieved by an internal latent image type core / shell direct positive silver halide photographic emulsion and a color diffusion transfer photosensitive material using the same.
(1) A tabular silver halide grain having an average grain diameter of 0.3 μm or more and an aspect ratio (equivalent circle diameter / grain thickness of silver halide grains) of 2 or more and 100 or less is 50% of the projected area of the total silver halide grains In addition, at least one metal ion of Cr, Mn, Cu, Zn, Cd, Pb, Bi, Re, Group 8 metal and lanthanide in the periodic table is included in both the core portion and the shell portion. And the metal ion concentration incorporated in the core portion is greater than or equal to the metal ion concentration incorporated in the shell portion. An internal latent image type direct positive silver halide emulsion.
( 2 ) Built-in metal ion concentration is 1.0 × 10 for both core and shell ^-6 Mol / mol Ag or more 1.0 × 10 ^-2 Mol / mol Ag or less (1) Description Internal latent image type direct positive silver halide emulsion.
( 3 The preceding item (1), wherein the built-in metal ion species is Pb. Or (2) Internal latent image type direct positive silver halide emulsion as described.
(4) on a support having at least one light-sensitive silver halide emulsion layer combined with a dye image-forming substance, wherein the dye image-forming substance is represented by the following general formula (I) In the color diffusion transfer light-sensitive material comprising a non-diffusible compound that releases a diffusible dye or a precursor thereof or a compound that changes its diffusibility, at least one of the silver halide emulsion layers is 1) to ( 3 A color diffusion transfer photosensitive material comprising the internal latent image type direct positive silver halide emulsion described in (1).
Formula (I)
(DYE-Y) nZ
{DYE represents a dye group, a temporarily shortened dye group or a dye precursor group, Y represents a simple bond or linking group, and Z corresponds to or is opposite to a photosensitive silver salt having a latent image in an image form. Correspondingly, a difference is caused in the diffusivity of the compound represented by the general formula (I), or DYE is released, and the diffusivity between the released DYE and the compound represented by the general formula (I) Represents a group having such a property as to cause a difference, n represents 1 or 2, and when n is 2, two DYE-Ys may be the same or different. }
[0009]
Hereinafter, the present invention will be described in more detail.
The metal used in the present invention may be added and contained during the preparation of silver halide grains, that is, at any stage before or after nucleation, growth, physical ripening, or chemical sensitization. The pAg when adding these metals during the preparation of silver halide grains is preferably 6 or more and 11 or less. When the particles are doped, it is preferably added after the formation of the particles, before the completion of the chemical sensitization when the particles are formed, or when used as a chemical sensitizer. A method of doping the entire particle, doping both the core and shell of the particle, or doping only the epitaxial portion or only the base particle can be selected.
[0010]
The metal dopant added during the formation of silver halide grains will be described.
In the present invention, manganese, chromium, copper, zinc, cadmium, lead, bismuth, rhenium, and at least one metal selected from Group 8 metals and lanthanides are added during the formation of silver halide emulsion grains. The
The metal used in the present invention can be added in the form of a salt that can be dissolved at the time of particle formation, such as ammonium salt, acetate salt, nitrate salt, sulfate salt, phosphate salt, hydrate salt or hexacoordinate complex salt or tetracoordinate complex salt. . For example, CdBr ₂ , CdCl ₂ , Cd (NO _Three ) ₂ , Pb (NO _Three ) ₂ , Pb (CH _Three (COO) ₂ , K _Three [Fe (CN) ₆ ], (NH _Four ) _Four [Fe (CN) ₆ ], K _Three IrCl ₆ , NH _Four RhCl ₆ , K _Four Ru (CN) ₆ Etc. The ligand of the coordination compound can be selected from halo, aco, cyano, cyanate, thiocyanate, nitrosyl, thionitrosyl, oxo and carbonyl. These may use only one type of metal compound, but may be used in combination of two or more.
[0011]
In another preferred embodiment, the added metal is preferably lead. In this case, lead is lead acetate [Pb (CH _Three (COO) ₂ ] Is preferably used.
[0012]
The amount of metal used in the present invention is 10 per mole of silver halide. ^-Ten Molar or more 1.0 × 10 ^-2 It is preferably less than or equal to a mole, and 1.0 × 10 6 per mole of silver halide ^-8 Molar or more 1.0 × 10 ^-2 More preferably, it is 1.0 mol / mol or less, more preferably 1.0 × 10 6 per mol of silver halide. ^-6 Molar or more 1.0 × 10 ^-2 Less than or equal to
The amount of metal added is 1.0 x 10 per mole of silver halide ^-2 Exceeding the mole is not preferable because the particles are deformed.
[0013]
The hydrogen ion concentration in the reaction solution when adding the metal used in the present invention is preferably pH = 1 or more, and more preferably pH = 3 or more.
[0014]
The metal compound used in the present invention is preferably added after dissolving in water or a suitable solvent such as methanol or acetone. In order to stabilize the solution, a method of adding an aqueous hydrogen halide solution (for example, HCl, HBr, etc.) or an alkali halide (for example, KCl, NaCl, KBr, NaBr, etc.) can be used. Moreover, you may add an acid, an alkali, etc. as needed. The metal compound can be added to the reaction vessel before the particle formation or can be added during the particle formation. Also, water-soluble silver salt (eg AgNO _Three ) Or an alkali halide aqueous solution (for example, NaCl, KBr, KI) and can be added continuously during the formation of silver halide grains. Further, a solution independent of the water-soluble silver salt and alkali halide may be prepared and added continuously at an appropriate time during grain formation. It is also preferable to combine various addition methods.
[0015]
Hereinafter, a specific configuration of the present invention will be described in detail.
The present invention applies to internal latent image type direct positive silver halide emulsions. An internal latent image type direct positive silver halide emulsion (hereinafter sometimes abbreviated as an internal latent image type silver halide emulsion) means that a latent image is mainly formed inside a silver halide grain when an image is exposed. In the case of a silver halide emulsion, specifically, a predetermined amount of a silver halide emulsion is coated on a transparent support, and this is exposed to light for a fixed time of 0.01 to 1 second. The maximum density obtained when developing at 20 ° C. for 5 minutes in the “internal type” developer) is 20% in the following developer B (“surface type” developer). Defined as having a density that is at least 5 times greater than the maximum density obtained when developed at 5 ° C. for 5 minutes.
Here, the maximum density is measured by an ordinary photographic density measuring method.
Developer A
N-methyl-p-aminophenol sulfite 2g
Sodium sulfite (anhydrous) 90g
Hydroquinone 8g
Sodium carbonate (monohydrate) 52.5g
Potassium bromide 5g
Potassium iodide 0.5g
1 liter with water
Developer B
N-methyl-p-aminophenol sulfite 2.5g
l-ascorbic acid 10g
35 g potassium metanitrate
Potassium bromide 1g
1 liter with water
Examples of the internal latent image type silver halide emulsion include conversion type silver halide emulsions described in US Pat. No. 2,456,953 and US Pat. No. 2,592,250, and US Pat. No. 3,935. , 014, etc., a laminated structure type silver halide emulsion having different halogen compositions in the first phase and the second phase, or a core grain doped with metal ions or chemically sensitized with a shell Core / shell type silver halide emulsions. Of these, the internal latent image type silver halide emulsion used in the present invention is particularly preferably a core / shell type silver halide emulsion. Examples thereof include U.S. Pat. Nos. 3,206,313 and 3,317,322. 3,761,266, 3,761,276, 3,850,637, 3,923,513, 4,035,185, 4,184,878, 4,395 No. 4,478, No. 4,504,570, JP-A 57-136641, 61-3137, JP-A 61-299155, JP-A 62-208241, and the like.
In order to obtain a direct positive image, a uniform second exposure is given to the front surface of the exposed layer after image exposure of the above-described internal latent image type silver halide emulsion before or during development ("light fogging") For example, British Patent 1,151,363) or development in the presence of a nucleating agent ("chemical fogging", eg Research Disclosure, Vol. 151, No. 15162, 76). In the present invention, a method of directly obtaining a positive image by the “chemical fogging method” is preferable. The nucleating agent used in the present invention will be described later.
As described above, in order to obtain a positive image directly using the internal latent image type silver halide emulsion, a uniform second exposure is given to the entire surface after image exposure, before development processing or at the time of development processing. It can be obtained by developing in the presence of a nucleating agent. Examples of the nucleating agent include hydrazines described in US Pat. Nos. 2,563,785 and 2,588,982, hydrazides, hydrazones described in US Pat. No. 3,227,552, British Patent 1,283, 835, JP-A-52-69613, 55-138742, 60-11837, 62-210451, 62-291737, U.S. Patents 3,615,515, 3,719,494, 3 734, 738, 4,094,683, 4,115,122, 4306016, 4447104, etc., and nucleation described in US Pat. No. 3,718,470. Sensitizing dye having functional substituent in dye molecule, U.S. Pat. Nos. 4,030,925, 4,031,127, 4,245,037, 4,255,51 4,266,013, 4,276,364, British Patent 2,012,443, and the like, and thiourea-linked acylhydrazine compounds described in U.S. Pat. No. 4,080,270, 4,278, 748, British Patent 2,011,391B and the like, and siahydrazine-based compounds in which a heterocyclic group such as a thioamide ring, triazole, tetrazole or the like is bonded as an adsorbing group are used.
The amount of the nucleating agent used here is desirably an amount that gives a sufficient maximum density when the internal latent image type emulsion is developed with a surface developer. Since the actual content varies depending on the characteristics of the silver halide emulsion used, the chemical structure of the nucleating agent and the development conditions, the appropriate content can vary over a wide range, but the silver in the internally latent silver halide emulsion A range of about 0.1 mg to 5 g per mole is practically useful, preferably about 0.5 mg to 2 g per silver mole. When it is contained in the hydrophilic colloid layer adjacent to the emulsion layer, the same amount as described above may be contained with respect to the amount of silver contained in the inner latent emulsion of the same area.
[0016]
The present invention applies to tabular internal latent image type direct positive silver halide emulsions. The shell of the present invention is a silver halide phase formed after chemical sensitization to the silver halide grains forming the core in the step of preparing an emulsion.
The internal latent image type silver halide grains used in the present invention preferably have a core / shell structure as described above.
The method for producing the shell is described in the examples of JP-A-63-151618, and U.S. Pat. Nos. 3,206,316, 3,317,322, 3,761,276, and 4,269,927. No. 3,367,778 can be referred to. In this case, the core / shell molar ratio (weight molar ratio) is preferably 1/30 to 5/1, more preferably 1/20 to 2/1, and still more preferably 1/20 to 1/1.
[0017]
Tabular grains are also described in Gatoff, Photographic Science and Engineering, Vol. 14, pages 248-257 (1970); U.S. Pat. No. 4,434,226, No. 4,414,310, No. 4,433,048, No. 4,439,520 and British Patent No. 2,112,157.
[0018]
The method of adding silver halide grains precipitated in advance to a reaction vessel for preparing an emulsion, US Pat. Nos. 4,334,012, 4,301,241 and 4,150,994 are preferred in some cases. These can be used as seed crystals, and are also effective when provided as silver halide for growth. In the latter case, it is preferable to add an emulsion having a small grain size. As the addition method, the whole amount can be added at once, divided into a plurality of times, or added continuously, or the like. It is also effective in some cases to add grains having various halogen compositions to modify the surface.
[0019]
In addition to the method of adding soluble silver salt and halogen salt at a constant concentration and constant flow rate for grain growth, British Patent No. 1,469,480, US Pat. Nos. 3,650,757 and 4,242,455 Particle formation methods that change the concentration or change the flow rate as described are preferred methods. By increasing the concentration or increasing the flow rate, the supplied silver halide amount can be changed by a linear function, a quadratic function, or a more complicated function of the addition time. It is also preferable in some cases to reduce the amount of supplied silver halide if necessary. In addition, when a plurality of soluble silver salts with different solution compositions are added, or when a plurality of soluble halogen salts with different solution compositions are added, an addition method of increasing one and reducing the other is also an effective method. It is.
US Pat. Nos. 2,996,287, 3,342,605, 3,415,650, and 3,785,777 are used as a mixer for reacting a soluble silver salt solution with a soluble halogen salt solution. , West German Patent Nos. 2,556,885 and 2,555,364 can be selected and used.
[0020]
When an emulsion containing tabular grains is produced, a silver salt solution (for example, AgNO 3) is added to accelerate grain growth. _Three A method of increasing the addition rate, addition amount, and addition concentration of an aqueous solution) and a halide solution (for example, an aqueous KBr solution) is preferable. With respect to these methods, for example, British Patent No. 1,335,925, U.S. Pat. Nos. 3,672,900, 3,650,757, 4,242,445, JP-A-55-142329. Nos. 55-158124 and the like can be referred to.
[0021]
It may be effective to add a chalcogenide compound as described in US Pat. No. 3,772,031 during emulsion preparation. In addition to S, Se, and Te, cyanate, thiocyanate, selenocyanate, carbonate, phosphate, and acetate may be present.
These are described in U.S. Pat. Nos. 2,448,060, 2,628,167, 3,737,313, 3,772,031, and Research Disclosure, Vol. 134, June 1975. , 13452, and the like.
[0022]
Triangular, hexagonal, circular, etc. can be selected as the tabular grain shape. A regular hexagonal shape having approximately the same length of the six sides as described in US Pat. No. 4,996,137 is a preferred form.
In the tabular emulsion of the present invention, silver halide grains having an aspect ratio (equivalent circle diameter / grain thickness of silver halide grains) of 2 to 100 are present in an amount of 50% (area) or more of all silver halide grains in the emulsion. Emulsion. Preferably, the silver halide grains having an aspect ratio of 5 or more, more preferably 5 to 8 are present in which 50% (area) or more of all silver halide grains in the emulsion are present, preferably 70%. Above, particularly preferably, the emulsion is present at 85% or more. Here, the equivalent circle diameter in tabular silver halide grains means the equivalent circle diameter of two opposing parallel or nearly parallel principal planes (diameter of a circle having the same projected area as the principal plane), grain thickness. Represents the distance between the main planes. On the other hand, when the aspect ratio exceeds 100, there is a problem that the emulsion may be deformed or destroyed in the process until the emulsion is completed as a coated product.
[0023]
The equivalent-circle diameter of the tabular grains is 0.3 μm or more, preferably 0.3 to 10 μm, more preferably 0.5 to 5.0 μm, and still more preferably 0.5 to 3.0 μm.
The particle thickness is less than 1.5 μm, preferably 0.05 to 1.0 μm.
Furthermore, an emulsion having a uniform thickness uniformity with a variation coefficient of grain thickness of 30% or less is also preferred. Furthermore, the particles described in JP-A No. 63-163451 that define the thickness of the particles and the distance between twin planes are also preferable.
Measurement of the grain diameter and grain thickness of the tabular grain can be obtained from an electron micrograph of the grain as in the method described in US Pat. No. 4,434,226.
[0024]
The grain size of the emulsion used in the present invention can be evaluated by the equivalent circle diameter of the projected area using an electron microscope, the equivalent sphere diameter of the grain volume calculated from the projected area and grain thickness, or the equivalent sphere diameter of the volume by the Coulter Counter method. From ultrafine particles having a sphere equivalent diameter of 0.05 μm or less, coarse particles exceeding 10 μm can be selected and used. Particles of 0.1 μm or more and 3 μm or less are preferable.
The grain size distribution of the silver halide grains is arbitrary but is preferably monodispersed. Here, the monodispersion is defined as a dispersion in which 95% of the total weight or the total number of silver halide grains contained therein falls within a range of ± 60%, preferably 40% of the number average grain size. The Here, the number average grain size is the number average diameter of the projected area diameter of the silver halide grains.
The structure and production method of monodispersed tabular grains are described in, for example, JP-A No. 63-151618, and these monodispersed emulsions may be mixed and used.
[0025]
As the silver halide composition of these grains, any silver halide of silver bromide, silver iodobromide, silver iodochlorobromide, silver chlorobromide, silver chloroiodide, and silver chloride may be used. However, silver bromide and silver iodobromide are preferred. In addition, other silver salts such as silver thiocyanate, silver cyanate, silver sulfide, silver selenide, silver carbonate, silver phosphate, and organic acid silver are included as separate grains or as part of silver halide grains. It may be.
[0026]
The silver halide grains may have different phases in the inside and the surface layer or may consist of a uniform phase. The silver halide composition in the grains may be uniform, may be composed of a silver halide composition having different inside and outside, or may have a layered structure. (JP-A-57-154232, 58-108533, 58-248469, 59-48755, 59-52237, U.S. Pat.Nos. 3,505,068 and 4,433,048) 4,444,877, European Patent No. 100,984, and British Patent No. 1,027,146), and particles having dislocation lines may also be used.
[0027]
In the case of silver halide grains in which two or more silver halides exist as mixed crystals or have a structure, it is important to control the halogen composition distribution between the grains. A method for measuring the halogen composition distribution between grains is described in JP-A-60-254032. It is a desirable characteristic that the halogen distribution between the grains is uniform. A highly uniform emulsion having a coefficient of variation of 20% or less is particularly preferable. Another preferred form is an emulsion having a correlation between grain size and halogen composition.
[0028]
It is important to control the halogen composition near the surface of the grains. Increasing the silver iodide content in the vicinity of the surface or increasing the silver chloride content can be selected according to the purpose because it changes the adsorptivity of the dye and the development speed. When changing the halogen composition in the vicinity of the surface, either a structure that wraps the whole grain or a structure that attaches only a part of the grain can be selected. For example, the halogen composition is changed only on one face of a tetradecahedral grain composed of the (100) face and the (111) face, or the halogen composition on one of the main plane or side face of the tabular grain is changed.
[0029]
Two or more kinds of silver halides having different crystal habit, halogen composition, grain size, grain size distribution, etc. can be used in combination, and can be used in different emulsion layers and / or the same emulsion layer. Is possible.
[0030]
In the silver halide emulsion of the present invention, it is preferable to chemically sensitize the grain surface after coating the shell on the core grain subjected to chemical sensitization, but it is not necessary to chemically sensitize the grain surface. . In general, chemical sensitization on the particle surface exhibits good reversal performance with a high maximum concentration. When chemical sensitization is performed on the particle surface, a polymer described in JP-A-57-13641 may coexist.
The above chemical sensitization is described by James, The Theory of the Photographic Process, 4th edition, published by Macmillan, 1977 (TH James, The Theory of the Photographic Process, 4th ed., Macmillan, 1977) active gelatin as described on pages 67-76, and Research Disclosure Volume 120, April 1974, 12008; Research Disclosure Volume 34, June 1975, 13452. U.S. Pat. Nos. 2,642,361, 3,297,446, 3,772,031, 3,857,711, 3,901,714, 4,266,018 , And 3,904,415 and British Patent 1,315,755, pAg 5-10, pH 4-8 and temperature 30-8. ℃ can sulfur, selenium, tellurium, gold, platinum, palladium, iridium, rhodium, osmium, Nireumu or be performed using a plurality of combinations of these sensitizers, at.
[0031]
Chemical sensitization can also be performed in the presence of a chemical sensitization aid. As the chemical sensitization aid used, compounds known to suppress fogging and increase sensitivity in the process of chemical sensitization, such as azaindene, azapyridazine, and azapyrimidine, are used. Examples of chemical sensitization aids include U.S. Pat. Nos. 2,131,038, 3,411,914, 3,554,757, JP-A-58-126536, 62-253159, and It is described in Duffin, “photographic emulsion chemistry”, pages 138 to 143 (published by Focal Press, 1966).
[0032]
As described in Japanese Examined Patent Publication No. 58-1410, Moisar et al., Journal of Photographic Science, Vol. 25, 1977, pp. 19-27, the silver halide emulsion is used in the precipitation process. The inside can be reduced and sensitized.
The following reduction sensitization can be used as chemical sensitization. As described in U.S. Pat. Nos. 3,891,446 and 3,984,249, for example, reduction sensitization can be performed using hydrogen, and U.S. Pat. Nos. 2,518,698, 2 , 743, 182 and 2,743, 183 using a reducing agent or by low pAg (eg less than 5) or high pH (eg greater than 8) treatment. it can. As typical reduction sensitizers, stannous salts, ascorbic acid and derivatives thereof, amines and polyamines, hydrazine derivatives, formamidinesulfinic acid, silane compounds, borane compounds and the like are known. In the reduction sensitization of the present invention, these known reduction sensitizers can be selected and used, and two or more compounds can be used in combination. As a reduction sensitizer, stannous chloride, thiourea dioxide, dimethylamine borane, ascorbic acid and derivatives thereof are preferable compounds.
The chemical sensitization methods described in US Pat. Nos. 3,917,485 and 3,966,476 can also be applied.
[0033]
Further, a sensitizing method using an oxidizing agent described in JP-A Nos. 61-3134 and 61-3136 can also be applied.
The oxidizing agent for silver refers to a compound having an action of acting on metallic silver and converting it into silver ions. Particularly effective are compounds capable of converting extremely fine silver grains by-produced in the process of silver halide grain formation and chemical sensitization into silver ions. The silver ions generated here may form a silver salt that is hardly soluble in water such as silver halide, silver sulfide, and silver selenide, or may form a silver salt that is easily soluble in water such as silver nitrate. Also good. The oxidizing agent for silver may be an inorganic substance or an organic substance. Inorganic oxidants include ozone, hydrogen peroxide and its adducts (eg, NaBO). ₂ ・ H ₂ O ₂ ・ 3H ₂ O.2NaCO _Three ・ 3H ₂ O ₂ , Na _Four P ₂ O ₇ ・ 2H ₂ O ₂ 2Na ₂ SO _Four ・ H ₂ O ₂ ・ 2H ₂ O), peroxyacid salts (eg K) ₂ S ₂ O ₈ , K ₂ C ₂ O ₆ , K ₂ P ₂ O ₈ ), Peroxy complex compounds (for example, K ₂ [Ti (O ₂ ) C ₂ O _Four ] 3H ₂ O, 4K ₂ SO _Four ・ Ti (O ₂ ) OH / SO _Four ・ 2H ₂ O, permanganate (eg KMnO _Four ), Chromate (eg K ₂ Cr ₂ O ₇ ), Halogen elements such as iodine and bromine, perhalogenates (for example, potassium periodate), and high valent metal salts (for example, potassium hexacyanoferric acid).
Examples of the organic oxidizing agent include quinones such as p-quinone, organic peroxides such as peracetic acid and perbenzoic acid, and compounds that release active halogen (for example, N-bromosuccinimide, chloramine T, chloramine B). ) As an example.
Preferred oxidizing agents of the present invention are organic oxidizing agents of ozone, hydrogen peroxide and its adducts, halogen elements and quinones. It is a preferred embodiment to use the aforementioned reduction sensitization in combination with an oxidizing agent for silver. The method can be selected from the method of performing post-reduction sensitization using an oxidizing agent, the reverse method, or the method of coexisting both at the same time. These methods can be selected and used in either the particle formation step or the chemical sensitization step.
[0034]
As the protective colloid used in preparing the emulsion of the present invention, gelatin is advantageously used, but other hydrophilic colloids can also be used.
For example, gelatin derivatives, graft polymers of gelatin and other polymers, proteins such as albumin and casein; cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose, cellulose sulfates, and sugar derivatives such as sodium alginate and starch derivatives; polyvinyl Various synthetic hydrophilic polymer materials such as single or copolymers such as alcohol, polyvinyl alcohol partial acetal, poly-N-vinyl pyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinyl imidazole, polyvinyl pyrazole, etc. Can be used.
As gelatin, in addition to lime-processed gelatin, acid-processed gelatin and Bull. Soc. Sci. Photo. 16, P30 (1966), an enzyme-treated gelatin may be used, and a hydrolyzate or enzyme-decomposed product of gelatin can also be used.
Although many impurity ions are contained in gelatin, it is also preferable to use gelatin in which the amount of inorganic impurity ions is reduced by ion exchange treatment.
[0035]
The emulsion of the present invention is preferably washed with water for desalting and dispersed in a newly prepared protective colloid. Although the temperature of water washing can be selected according to the objective, it is preferable to select in the range of 5-50 degreeC. Although pH at the time of water washing can also be chosen according to the objective, it is preferred to choose between 2-10. More preferably, it is the range of 3-8. Although pAg at the time of water washing can also be selected according to the objective, it is preferable to select between 5-10. The washing method can be selected from a noodle washing method, a dialysis method using a semipermeable membrane, a centrifugal separation method, a coagulation sedimentation method, and an ion exchange method. In the case of the coagulation sedimentation method, a method using a sulfate, a method using an organic solvent, a method using a washing polymer, a method using a gelatin derivative and the like can be selected.
[0036]
In the present invention, spectral sensitization can be performed using a sensitizing dye. Examples of the sensitizing dye to be used include a cyanine dye, a merocyanine dye, a composite cyanine dye, a composite merocyanine dye, a holopolar cyanine dye, a hemicyanine dye, a styryl dye, and a hemioxonol dye. Specifically, U.S. Pat. No. 4,617,257, JP-A-59-180550, JP-A-60-140335, JP-A-61-160739, RD17029 (1978) 12-13, RD17643 (1978) Sensitizing dyes described on page 23, and the like.
[0037]
These sensitizing dyes may be used alone or in combination, and a combination of sensitizing dyes is often used for the purpose of supersensitization. Typical examples thereof are US Pat. Nos. 2,688,545, 2,977,229, 3,397,060, 3,522,052, 3,527,641, and 3,617. No. 3,293, No. 3,628,964, No. 3,666,480, No. 3,672,898, No. 3,679,428, No. 3,703,377, No. 3,769,301 No. 3,814,609, No. 3,837,862, No. 4,026,707, British Patent Nos. 1,344,281, No. 1,507,803, No. 43-4936 53-12375, JP-A 52-110618, and 52-109925.
[0038]
Along with the sensitizing dye, the emulsion itself may contain a dye having no spectral sensitizing action or a substance that does not substantially absorb visible light and exhibits supersensitization. (For example, U.S. Pat. Nos. 3,615,613, 3,615,641, 3,617,295, 3,635,721, 2,933,390, 3,743,510) And those described in JP-A-63-23145).
The time for adding the sensitizing dye for spectral sensitization to the emulsion may be any stage of emulsion preparation which has been known to be useful so far. Most commonly, it is carried out after completion of chemical sensitization and before application, but as described in U.S. Pat. Nos. 3,628,969 and 4,225,666, Spectral sensitization can be performed simultaneously with chemical sensitization by adding at the same time, or can be performed prior to chemical sensitization as described in JP-A-58-113928. Spectral sensitization can be started by adding before the completion of the step. Furthermore, as taught in U.S. Pat. No. 4,225,666, these compounds are added separately, i.e. some of these compounds are added prior to chemical sensitization and the remainder is chemically enhanced. It can be added after the sensitization, and may be any time during the formation of silver halide grains, including the method disclosed in US Pat. No. 4,183,756.
[0039]
The amount added is 10 per mole of silver halide. ^-8 -10 ^-2 In the case of a more preferable silver halide grain size of 0.2 to 1.2 μm, about 5 × 10 ^-Five ~ 2x10 ^-3 Mole is more effective.
[0040]
The coating amount of the photosensitive silver halide used in the present invention is 1 mg to 10 g / m in terms of silver. ² Range.
[0041]
In the present invention, various antifoggants and photographic stabilizers can be used for the purpose of preventing sensitivity reduction and fogging. Examples thereof include azoles and azaindenes described in RD 17643 (1978) 24-25, US Pat. No. 4,629,678, and nitrogen-containing carboxylic acids and phosphoric acids described in JP-A-59-168442. Alternatively, mercapto compounds and metal salts thereof described in JP-A No. 59-111636, acetylene compounds described in JP-A No. 62-87957, and the like are used.
Further, phenethyl alcohol, 1,2-benzisothiazolin-3-one, n-butyl, P-hydroxybenzoate, phenol described in JP-A-63-257747, JP-A-62-272248, and JP-A-1-80941 It is preferable to add various preservatives or antifungal agents such as 4-chloro-3,5-dimethylphenol, 2-phenoxyethanol, 2- (4-thiazolyl) benzimidazole. The details are described in European Patent No. 436, 938A2, page 150, lines 25-28. These additives are described in more detail in Research Disclosure Item 17643 (1978), Item 18716 (November 1979) and Item 307105 (November 1989), and the corresponding parts are summarized in the table below. Showed.
[0042]

[0043]
Hereinafter, each component included in the present invention will be sequentially described.
I. Photosensitive sheet
A) Support
The support of the photosensitive sheet used in the present invention is any smooth transparent support that is usually used for photographic photosensitive materials, and cellulose acetate, polystyrene, polyethylene terephthalate, polycarbonate, etc. are used, and an undercoat layer is provided. preferable. The support usually contains a trace amount of a dye or a pigment such as titanium oxide in order to prevent light piping.
The thickness of the support is 50 to 350 μm, preferably 70 to 210 μm, more preferably 80 to 150 μm.
If necessary, a curl-balancing layer or an oxygen barrier layer described in JP-A-56-78833 can be provided on the back side of the support.
[0044]
B) Image receiving layer
The dye image-receiving layer used in the present invention contains a mordant in a hydrophilic colloid. This may be a single layer or a multilayer structure in which mordants having different mordant powers are applied in layers. This is described in JP-A-61-252551. As the mordant, a polymer mordant is preferable.
The polymer mordant is a polymer containing secondary and tertiary amino groups, a polymer having a nitrogen-containing heterocyclic moiety, a polymer containing a quaternary cation, etc., having a molecular weight of 5,000 or more, particularly preferably 10,000 or more. It is.
The coating amount of the mordant is generally 0.5 to 1.0 g / m. ² Preferably 1.0-5.0 g / m ² Particularly preferably 2 to 4 g / m ² It is.
As the hydrophilic colloid used in the image receiving layer, gelatin, polyvinyl alcohol, polyacrylamide, polyvinylpyrrolidone and the like are used, and gelatin is preferable.
In the image receiving layer, anti-fading agents described in JP-B-62-30620, JP-A-62-30621, and JP-A-62-215,272 can be incorporated.
[0045]
C) White reflective layer
The white reflective layer forming the white background of the color image usually contains a white pigment and a hydrophilic binder.
As the white pigment for the white reflective layer, barium sulfate, zinc oxide, barium stearate, silver flakes, silicates, alumina, zirconium oxide, zirconium zirconium sulfate, kaolin, mica, titanium dioxide and the like are used. Further, non-film-forming polymer particles made of styrene or the like are also used. These may be used alone, or may be mixed and used within a range in which a desired reflectance can be obtained.
A particularly useful white pigment is titanium dioxide.
The whiteness of the white reflective layer varies depending on the type of pigment, the mixing ratio of the pigment and the binder, and the coating amount of the pigment, but the light reflectance is desirably 70% or more. In general, the higher the amount of pigment applied, the better the whiteness, but when the image-forming dye diffuses through this layer, the pigment becomes resistant to dye diffusion and therefore has a moderate amount of application. Is desirable.
5-40 g / m of titanium dioxide ² , Preferably 10 to 25 g / m ² A white reflective layer that is applied and has a light reflectance of 78-85% with light having a wavelength of 540 mm is preferred.
Titanium dioxide can be selected from various commercially available brands.
Of these, rutile type titanium dioxide is particularly preferred.
Most of the commercial products are surface-treated with alumina, silica, zinc oxide or the like, and in order to obtain a high reflectance, a surface treatment amount of 5% or more is desirable. Examples of commercially available titanium dioxide include those described in Research Disclosure Magazine No. 15162 in addition to Ti-pure R931 manufactured by DuPont.
As the binder for the white reflective layer, an alkali-permeable polymer matrix such as gelatin, polyvinyl alcohol, cellulose derivatives such as hydroxyethyl cellulose and carboxymethyl cellulose can be used.
A particularly desirable binder for the white reflective layer is gelatin. The ratio of the white pigment to gelatin is 1/1 to 20/1 (weight ratio), preferably 5/1 to 10/1 (weight ratio).
It is preferable to incorporate an anti-fading agent such as Japanese Patent Publication Nos. 62-30620 and 62-30621 in the white reflective layer.
[0046]
D) Shading layer
A light shielding layer containing a light shielding agent and a hydrophilic binder may be provided between the white reflective layer and the photosensitive layer.
As the light shielding agent, any material having a light shielding function is used, but carbon black is preferably used. Decomposable dyes described in US Pat. No. 4,615,966 may also be used.
The binder for coating the light-shielding agent may be any one that can disperse carbon black, and is preferably gelatin.
As the carbon black raw material, any production method such as a channel method, a thermal method, and a furnace method as described in Donnel Voet “Carbon Black” Marcel Dekker, Inc. (1976) can be used. The particle size of carbon black is not particularly limited, but is preferably 90 to 1800 mm. The addition amount of the black pigment as the light-shielding agent may be adjusted according to the sensitivity of the photosensitive material to be shielded from light, but is preferably about 5 to 10 in terms of optical density.
[0047]
E) Photosensitive layer
In the present invention, a photosensitive layer comprising a silver halide emulsion layer combined with a dye image forming substance is provided above the light shielding layer. The components are described below.
(1) Dye image forming substance
The dye image-forming substance used in the present invention is a non-diffusible compound that releases a diffusible dye (which may be a dye precursor) in connection with silver development, or has its own diffusivity changed, It is described in "The Theory of the Photographic Process" 4th edition. Any of these compounds can be represented by the following general formula [I].
Formula [I]
(DYE-Y) _n -Z
{DYE represents a dye group, a temporarily shortened dye group or a dye precursor group, Y represents a simple bond or linking group, and Z corresponds to or is opposite to a photosensitive silver salt having a latent image in an image form. Correspondingly (DYE-Y) _n A difference in the diffusivity of the compound represented by -Z or release of DYE, and the released DYE and (DYE-Y) _n Represents a group having a property of causing a difference in diffusibility with -Z, n represents 1 or 2, and when n is 2, two DYE-Y may be the same or different. }
According to the function of Z, it is roughly divided into a negative compound that becomes diffusible in the silver developing portion and a positive compound that becomes diffusible in the undeveloped portion.
Specific examples of the negative type Z include those that are oxidized as a result of development and cleaved to release a diffusible dye.
Specific examples of Z are U.S. Pat. Nos. 3,928,312, 3,993,638, 4,076,529, 4,152,153, 4,055,428 and 4,053. 312; 4,198,235; 4,179,291; 4,149,892; 3,844,785; 3,443,943; 3,751,406 No. 3,443,939, No. 3,443,940, No. 3,628,952, No. 3,980,479, No. 4,183,753, No. 4,142,891, 4,278,750, 4,139,379, 4,218,368, 3,421,964, 4,199,355, 4,199,354, 4, 135,929, 4,336,322, 4,139,389, No. 53-50736, No. 51-104343, No. 54-130122, No. 53-110627, No. 56-12642, No. 56-16131, No. 57-4043, No. 57-650, 57-20735, 53-69033, 54-130927, 56-164342, 57-119345 and the like.
Among Z of the negative type dye-releasing redox compound, particularly preferable group includes an N-substituted sulfamoyl group (the N-substituent is a group derived from an aromatic hydrocarbon ring or a heterocyclic ring). Representative groups of Z are exemplified below, but are not limited thereto.
[0048]
[Chemical 1]

[0049]
The positive type compound is described in Angelev. Chem. Int. Ed. Engl., 22, 191 (1982).
Specific examples include compounds (dye developers) that are initially diffusible under alkaline conditions but become non-diffusible when oxidized by development. Typical examples of Y effective for this type of compound are those listed in US Pat. No. 2,983,606.
As another type, a diffusible dye is released by, for example, self-cyclization under alkaline conditions, but the dye is not substantially released when oxidized with development. Specific examples of Y having such a function include US Pat. No. 3,980,479, JP-A-53-69033, JP-A-54-130927, US Pat. Nos. 3,421,964, 4,199, No. 355.
Another type is one that does not release the dye itself, but releases the dye when reduced. This type of compound can be used in combination with an electron donor to release imagewise diffusible dyes by reaction with the remaining electron donor imagewise oxidized by silver development. As for the atomic group having such a function, for example, U.S. Pat. Nos. 4,183,753, 4,142,891, 4,278,750, 4,139,379, 4,218, 368, JP-A-53-110827, U.S. Pat.Nos. 4,278,750, 4,356,249, 4,358,535, JP-A-53-110827, 54-130927, No. 56-164342, published technical report 87-6199, European Patent Publication No. 220746A2, and the like.
Although the specific example is illustrated below, it is not limited only to these.
[0050]
[Chemical formula 2]

[0051]
When this type of compound is used, it is preferably used in combination with a diffusion-resistant electron donating compound (known as an ED compound) or a precursor (precursor) thereof. Examples of the ED compound are described in, for example, U.S. Pat. Nos. 4,263,393, 4,278,750, and Japanese Patent Laid-Open No. 56-138736.
As specific examples of another type of dye image forming substance, the following can also be used.
[0052]
[Chemical 3]

[0053]
Details thereof are described in US Pat. Nos. 3,719,489 and 4,098,783.
On the other hand, specific examples of the dye represented by DYE of the above general formula are described in the following documents.
Examples of yellow dyes:
U.S. Pat.Nos. 3,597,200, 3,309,199, 4,013,633, 4,245,028, 4,156,609, 4,139,383, 4,195,992, 4,148,641, 4,148,643, 4,336,322: JP-A-51-114930, 56-71072: Research Disclosure 17630 (1978) ) And 16475 (1977).
Examples of magenta dyes:
U.S. Pat.Nos. 3,453,107, 3,544,545, 3,932,380, 3,931,144, 3,932,308, 3,954,476, 4,233,237, 4,255,509, 4,250,246, 4,142,891, 4,207,104, 4,287,292: 52-106,727, 53-23,628, 55-36,804, 56-73,057, 56-71060, 55-134.
Examples of cyan dyes:
U.S. Patents 3,482,972, 3,929,760, 4,013,635, 4,268,625, 4,171,220, 4,242,435, 4,142,891, 4,195,994, 4,147,544, 4,148,642; British Patent 1,551,138; JP-A-54-99431, 52 -8827, 53-47823, 53-143323, 54-99431, 56-71061; European Patent (EP) 53,037, 53,040; Research Disclosure 17,630 ( 1978) and 16,475 (1977).
These compounds can be dispersed by the method described in JP-A-62-215,272, pages 144-146. These dispersions may contain compounds described in JP-A-62-215,272, pages 137-144.
[0054]
(2) Silver halide emulsion
In the present invention, the following various internal latent image type direct positive silver halide emulsions can be used in combination with the above-mentioned tabular internal latent image type direct positive silver halide emulsion. Examples include those having regular crystal shapes such as cubes, octahedrons, tetradecahedrons, rhombohedral dodecahedrons, those having irregular crystal shapes such as spheres, plates, etc. Examples thereof include those having the following plane ((hk1) plane), or a mixture of grains of these crystal forms. As for particles having higher-order surfaces, pages 247 to 254 of Journal of Imaging Science, Vol. 30 (1986) can be referred to.
The silver halide grains used in the present invention may be normal crystals that do not contain twin planes, but are edited by the Japan Photographic Society, the foundation of the photographic industry, silver salt photography (Corona), p. Examples as described in 163, for example, single twins including one twin plane, parallel multiple twins including two or more parallel twin planes, non-parallel including two or more non-parallel twin planes It can be selected from multiple twins according to the purpose.
An example in which particles having different shapes are mixed is disclosed in US Pat. No. 4,865,964, and this method can be selected as necessary.
In the case of a normal crystal, a cube consisting of (100) faces, an octahedron consisting of (111) faces, and a twelve (110) faces disclosed in Japanese Examined Patent Publication Nos. 55-42737 and 60-222842 Faceted particles can be used. Furthermore, (hl1) face particles represented by (211) as reported in Journal of Imaging Science, Vol. 30, 247, 1986, (hh1) face particles represented by (331), ( The (hk0) face particles represented by the 210) face and the (hk1) face grains represented by the (321) face need to be devised in the preparation method, but can be selected and used according to the purpose.
Tetrahedral particles in which (110) plane and (111) plane coexist in one particle, particles in which (100) plane and (110) plane coexist, or particles in which (111) plane and (110) plane coexist For example, particles in which two surfaces or many surfaces coexist can be selected and used according to the purpose.
[0055]
The silver halide composition of these grains and the grain size of the emulsion can be selected from those similar to the above-mentioned tabular internal latent image type direct positive silver halide emulsion.
[0056]
The silver halide emulsion used in the present invention is a treatment for rounding grains as disclosed in European Patent Nos. 96,727B1 and 64,412B1, or West German Patent No. 2,306,447C2, JP Surface modification as disclosed in JP-A-60-221320 may be performed.
A structure with a flat particle surface is generally used, but it is sometimes desirable to intentionally form irregularities. A method of making a hole in a part of a crystal described in JP-A-58-106532 and 60-221320, for example, a vertex or the center of a surface, or a raffle described in US Pat. No. 4,643,966 An example is particles.
[0057]
Two or more kinds of silver halides having different crystal habit, halogen composition, grain size, grain size distribution, etc. can be used in combination, and can be used in different emulsion layers and / or the same emulsion layer. Is possible.
[0058]
The silver halide grains described above are available from Research Disclosure (RD) No. 17643 (December 1978), pp. 22-23, “I. Emulsion preparation and types”, and ibid. 18716 (November 1979), page 648, ibid. 307105 (November 1989), pages 863-865, and Grafkide, "Physics and Chemistry of Photography", published by Paul Montel (P. Glafkides Chimie et Pysique Photograhique, Paul Montel, 1967), "Photoemulsion Chemistry". Published by Focal Press (GFDuffin, Photographic Emulsion Chemistry, Focal Press, 1966), “Manufacture and coating of photographic emulsions” by Zerikman et al., Published by Focal Press (VLZelikman et al, Making and Coating Photographic Emulsion, Focal Press, 1964) Can be prepared using the methods described in the above. That is, any of an acidic method, a neutral method, an ammonia method, etc. may be used, and any one of a one-side mixing method, a simultaneous mixing method, and a combination thereof may be used as a form for reacting a soluble silver salt and a soluble halogen salt. Good. A method (so-called back mixing method) in which grains are formed in the presence of excess silver ions can also be used. As one type of the simultaneous mixing method, a method of keeping pAg in a liquid phase generated by silver halide constant, that is, a so-called controlled double jet method can be used. According to this method, a silver halide emulsion having a regular crystal form and a nearly uniform grain size can be obtained.
[0059]
The silver halide grains composed of the normal crystals can be obtained by controlling the pAg and pH during grain formation. For details, see, for example, Photographic Science and Engineering, Vol. 6, pp. 159-165 (1962); Journal of Photographic Science, Vol. 12, 242 ˜251 (1964), US Pat. No. 3,655,394 and British Patent 1,413,748.
Monodispersed emulsions are disclosed in JP-A-48-8600, 51-39027, 51-83097, 53-137133, 54-48521, 54-99419, 58-37635. 58-49938, Japanese Patent Publication No. 47-11386, U.S. Pat. No. 3,655,394, British Patent No. 1,413,748, and the like.
[0060]
Methods for converting most or a small part of the halogen composition of silver halide grains by the halogen conversion method are described in US Pat. Nos. 3,477,852 and 4,142,900, European Patents 273,429 and 273. No. 430, West German Patent No. 3,819,241 and the like, which are effective particle forming methods. A soluble halogen solution or silver halide grains can be added to convert to a more sparingly soluble silver salt. You can choose from methods that convert at once, convert multiple times, or convert continuously.
[0061]
In addition to the method of adding soluble silver salt and halogen salt at a constant concentration and constant flow rate for grain growth, British Patent No. 1,469,480, US Pat. Nos. 3,650,757 and 4,242,455 Particle formation methods that change the concentration or change the flow rate as described are preferred methods. By increasing the concentration or increasing the flow rate, the supplied silver halide amount can be changed by a linear function, a quadratic function, or a more complicated function of the addition time.
[0062]
Similar to the above-mentioned tabular internal latent image type direct positive silver halide emulsion, the presence of a metal ion salt before the above-mentioned emulsion preparation, for example, during grain formation, desalting step, chemical sensitization, before coating It is preferable depending on the purpose. Also, a method of adding a chalcogenide compound as described in US Pat. No. 3,772,031 during emulsion preparation may be effective.
[0063]
The internal latent image type silver halide grains used in the present invention preferably have a core / shell structure as described above. Shell manufacturing method, method of applying chemical sensitization to particle surface after coating shell on core particles subjected to chemical sensitization, chemical sensitization in the presence of chemical sensitization aid, reduction sensitization, or The sensitizing method using an oxidizing agent can also be carried out in the same manner as the above-mentioned tabular internal latent image type direct positive silver halide emulsion.
[0064]
Selection of protective colloid, washing method for desalting, spectral sensitization method using sensitizing dye, use of various antifoggants and photographic stabilizers for the purpose of preventing sensitivity reduction and fogging, etc. Can be carried out in the same manner as the above-mentioned tabular internal latent image type direct positive silver halide emulsion.
[0065]
(3) Structure of photosensitive layer
The reproduction of natural colors by the subtractive color method involves at least two of the combination of the emulsion spectrally sensitized with the spectral sensitizing dye and the dye image-forming substance that provides a dye having selective spectral absorption in the same wavelength range. A photosensitive layer consisting of two is used. The emulsion and the dye image-forming substance may be coated as separate layers, or may be mixed and coated as a single layer. When the dye image-forming substance is coated and has absorption in the spectral sensitivity range of the emulsion combined therewith, a separate layer is preferred. The emulsion layer may be composed of a plurality of emulsion layers having different sensitivities, and an arbitrary layer may be provided between the emulsion layer and the dye image-forming substance layer. For example, a layer containing a nucleation development accelerator described in JP-A-60-173541 and a partition layer described in JP-B-60-15267 are provided to increase the color image density, or a reflection layer is provided for photosensitivity. You can also increase the sensitivity of the element.
The reflective layer is a layer containing a white pigment and a hydrophilic binder. Preferably, the white pigment is titanium oxide and the hydrophilic binder is gelatin. The amount of titanium oxide applied is 0.1 g / m ² ~ 8g / m ² , Preferably 0.2 g / m ² ~ 4g / m ² It is. An example of the reflective layer is described in JP-A-60-91354.
In a preferred multi-layer structure, a blue-sensitive emulsion combination unit, a green-sensitive emulsion combination unit, and a red-sensitive emulsion combination unit are sequentially arranged from the exposure side.
Arbitrary layers can be provided between the respective emulsion layer units as required. In particular, it is preferable to provide a color mixing prevention layer in order to prevent an unfavorable influence of the development effect of a certain emulsion layer on other emulsion layer units.
When a developer is used in combination with a non-diffusible dye image forming substance, the color mixing prevention layer preferably contains a non-diffusible reducing agent in order to prevent diffusion of the oxidized developer. Specific examples include non-diffusible hydroquinone, sulfonamidophenol, sulfonamidonaphthol and the like. More specifically, Japanese Patent Publication Nos. 50-21249 and 50-23813, Japanese Patent Publication Nos. 49-106329 and 49. -129535, U.S. Pat. Nos. 2,336,327, 2,360,290, 2,403,721, 2,544,640, 2,732,300, 2,782, No. 659, No. 2,937,086, No. 3,637,393, No. 3,700,453, British Patent No. 557,750, JP-A-57-24941, No. 58-21249, etc. Has been. In order to prevent the undesired transfer of these reducing agents to the emulsion layer and to adjust the activity as a reducing agent, it is preferably used by dispersing with a polymer. Preferred polymers include polyvinyl acetate, polymethyl methacrylate, polyacrylamide derivatives and the like. Their dispersion methods are described in JP-A-60-238831 and JP-B-60-18978.
In the case of using a compound that releases a diffusible dye by silver ions as described in JP-B-55-7576, it is preferable to contain a compound that supplements silver ions in the color mixing prevention layer.
In the present invention, an irradiation prevention layer, a UV absorber layer, a protective layer, and the like are coated as necessary.
If necessary, a partition wall layer made of gelatin can be provided between any adjacent layers.
[0066]
A development inhibitor precursor, a diffusion-resistant reducing agent, or the like can be incorporated in an arbitrary layer of the photosensitive layer in order to prevent fogging and adjust the photographic gradation.
[0067]
Any hydrophilic binder can be used for the photosensitive layer as long as it can penetrate the processing solution and transfer the image dye. For example, gelatin, polyacrylamide, polyvinyl alcohol or derivatives thereof.
The hydrophilic binder may be hardened with a hardener, and 0.5% to 5%, preferably 0.5 to 2% of the hydrophilic binder is added.
[0068]
F) Release layer
In the present invention, if necessary, a release layer can be provided for peeling off at any place on the photosensitive sheet in the unit after processing.
Therefore, this release layer must be easy to release after treatment. As materials for this, for example, JP-A-47-8237, 59-220727, 59-229555, 49-4653, U.S. Pat. Nos. 3,220,835, 4,359, No. 518, JP-A Nos. 49-4334, 56-65133, 45-24075, U.S. Pat.Nos. 3,227,550, 2,759,825, 4,401,746, What was described in 4,366,227 etc. can be used. One specific example is a water-soluble (or alkali-soluble) cellulose derivative. For example, hydroxyethyl cellulose, cellulose acetate phthalate, plasticized methyl cellulose, ethyl cellulose, cellulose nitrate, carboxymethyl cellulose, and the like. Other examples include various natural polymers such as alginic acid, pectin, gum arabic and the like. Various modified gelatins such as acetylated gelatin and phthalated gelatin are also used. Still another example is a water-soluble synthetic polymer. For example, polyvinyl alcohol, polyacrylate, polymethyl methacrylate, polybutyl methacrylate, or a copolymer thereof.
The release layer may be a single layer or may be composed of a plurality of layers as described in, for example, JP-A Nos. 59-220727 and 60-60642.
[0069]
II. Cover sheet
In the present invention, a layer having a neutralization function (neutralization layer and neutralization timing layer) is used to uniformly spread the processing solution on the photosensitive element, neutralize the alkali after processing, and stabilize the image. Use a transparent cover sheet with
[0070]
G) Support
The support for the cover sheet used in the present invention is any smooth transparent support usually used for photographic materials, and cellulose acetate, polystyrene, polyethylene terephthalate, polycarbonate, etc. are used, and an undercoat layer is provided. preferable.
The support preferably contains a trace amount of dye to prevent light piping.
[0071]
H) Layer having a neutralizing function
The layer having a neutralizing function used in the present invention is a layer containing an acidic substance in an amount sufficient to neutralize the alkali introduced from the treatment composition, and if necessary, a neutralization rate adjusting layer (timing layer). ), A multilayer structure composed of layers such as an adhesion reinforcing layer may be used. A preferable acidic substance is a substance containing an acidic group having a pKa of 9 or less (or a precursor group that gives such an acidic group by hydrolysis), more preferably oleic acid described in US Pat. No. 2,983,606. Higher fatty acids such as, polymers of acrylic acid, methacrylic acid or maleic acid and partial esters or acid anhydrides thereof as disclosed in US Pat. No. 3,362,819; French Patent 2,290,699 A copolymer of acrylic acid and an acrylate ester as disclosed in US Pat. No. 4,139,383 and Research Disclosure No. Mention may be made of latex-type acidic polymers as disclosed in US Pat. No. 16102 (1977).
In addition, US Patent No. 4,088,493, JP-A-52-153, 739, 53-1, 023, 53-4, 540, 53-4, 541, 53-4, An acidic substance disclosed in No. 542 and the like can also be mentioned.
Specific examples of acidic polymers include copolymers of vinyl monomers such as ethylene, vinyl acetate, vinyl methyl ether, and maleic anhydride, and their n-butyl esters, copolymers of butyl acrylate and acrylic acid, cellulose, and acetate.・ Hydrodiene phthalate.
The polymer acid can be used as a mixture with a hydrophilic polymer. Examples of such a polymer include polyacrylamide, polymethylpyrrolidone, polyvinyl alcohol (including partially saponified product), carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, polymethyl vinyl ether, and the like. Of these, polyvinyl alcohol is preferred.
The polymer acid may be mixed with a polymer other than the hydrophilic polymer, such as cellulose acetate.
The amount of polymer acid applied is controlled by the amount of alkali developed on the photosensitive element. The equivalent ratio of polymer acid to alkali per unit area is preferably 0.9 to 2.0. If the amount of the polymer acid is too small, the hue of the transfer dye changes or stains are produced in the white background, and if it is too much, problems such as a change in hue or a decrease in light resistance occur. A more preferred equivalent ratio is 1.0 to 1.3. If the amount of the hydrophilic polymer to be mixed is too large or too small, the quality of the photograph is deteriorated. The weight ratio of the hydrophilic polymer to the polymer acid is 0.1 to 10, preferably 0.3 to 3.0.
Additives can be incorporated into the layer having a neutralizing function of the present invention for various purposes. For example, hardeners well known to those skilled in the art to harden this layer, or polyhydric hydroxyl compounds such as polyethylene glycol, polypropylene glycol, glycerin, etc., can be added to improve the brittleness of the film. In addition, an antioxidant, a fluorescent brightening agent, a development inhibitor, and a precursor thereof can be added as necessary.
The timing layer used in combination with the neutralization layer is a polymer that reduces alkali permeability, such as gelatin, polyvinyl alcohol, partially acetalized polyvinyl alcohol, cellulose acetate, partially hydrolyzed polyvinyl acetate, and the like; Latex polymers produced by copolymerizing a small amount of a hydrophilic comonomer such as an acrylic acid monomer, which increase the activation energy for alkali permeation; polymers having a lactone ring, and the like are useful.
Among them, a timing layer using cellulose acetate disclosed in JP-A-54-136328, US Pat. Nos. 4,267,262, 4,009,030, 4,029,849, etc .; Kaisho 54-128335, 56-69,629, 57-6,843, U.S. Pat.Nos. 4,056,394, 4,061,496, 4,199,362, 4 , 250, 243, 4, 256, 827, 4, 268, 604, etc .; latex polymers made by copolymerizing a small amount of a hydrophilic comonomer such as acrylic acid; , 229,516, polymers having a lactone ring; JP-A-56-25735, JP-A-56-97346, JP-A-57-6842, European Patent (EP) 31,95 No. A1, the 37,724A1 No., polymers disclosed in such Patent same 48,412A1 are especially useful.
In addition, those described in the following documents can also be used.
U.S. Pat.Nos. 3,421,893, 3,455,686, 3,575,701, 3,778,265, 3,785,815, 3,847,615, 4,088,493, 4,123,275, 4,148,653, 4,201,587, 4,288,523, 4,297,431, West German patent applications (OLS) 1,622,936, 2,162,277, Research Disclosure 15162, No. 151 (1976).
The timing layer using these materials can be used as a single layer or as a combination of two or more layers.
In addition, for example, U.S. Pat. No. 4,009,029, West German Patent Applications (OLS) 2,913,164, 3,014,672, JP-A No. 54-155837, 55-138745, etc., development inhibitors and / or precursors thereof, hydroquinone precursors disclosed in US Pat. No. 4,201,578, other useful photographic additives or precursors thereof, etc. It can also be incorporated.
Further, as a layer having a neutralizing function, providing an auxiliary neutralizing layer as described in JP-A Nos. 63-168648 and 63-168649 reduces the change in transfer density over time after processing. effective.
[0072]
I) Other
In addition to the layer having a neutralizing function, a back layer, a protective layer, a filter dye layer, or the like may be provided as a layer having an auxiliary function.
The back layer is provided for adjusting curl and imparting slipperiness. Filter dyes may be added to this layer.
In the monosheet type photosensitive material, the protective layer is mainly used for preventing adhesion with the cover sheet back surface and adhesion with the photosensitive material protective layer when the photosensitive material and the cover sheet are overlapped.
The capture mordant layer can prevent a delay in image completion time and deterioration of sharpness by capturing the dye diffused to the alkali treatment composition side. Usually, a dye capturing layer is provided on the outermost layer of the cover sheet. Similar to the dye image-receiving layer described above, the dye capturing layer contains a polymer mordant in a hydrophilic colloid, and is described in JP-A-1-198747 and JP-A-2-282253.
The sensitivity of the photosensitive layer can be adjusted by incorporating a dye into the cover sheet. The filter dye may be added directly to the support of the cover sheet or to the layer having a neutralizing function, and further to the back layer, protective layer, capture mordant layer, etc., or a single layer may be provided. .
[0073]
III. Alkali treatment composition
The processing composition used in the present invention is developed uniformly on the photosensitive element after exposure of the photosensitive element, and the photosensitive layer is developed with the components contained therein. For this purpose, the composition contains an alkali, a thickener, a developer, a development accelerator for controlling development, a development inhibitor, an antioxidant for preventing deterioration of the developer, a gradation. Contains a regulator, etc.
The alkali is sufficient to adjust the pH of the liquid to 12 to 14, and alkali metal hydroxides (for example, sodium hydroxide, potassium hydroxide, lithium hydroxide), alkali metal phosphates (for example, potassium phosphate) , Guanidines, and hydroxides of quaternary amines (for example, tetramethylammonium hydroxide), among which potassium hydroxide and sodium hydroxide are preferable, and potassium hydroxide is particularly preferable.
The thickener is necessary for uniformly spreading the processing solution and for maintaining close contact between the photosensitive layer / cover sheet. For example, an alkali metal salt of polyvinyl alcohol, hydroxyethyl cellulose, or carboxymethyl cellulose is used. Of these, hydroxyethylcellulose, sodium hydroxymethylcarboxylate, and carboxymethyl-hydroxyethylcellulose are used.
[0074]
As the preferred developing agent, any one that cross-oxidizes the dye image-forming substance and does not substantially produce stain even when oxidized can be used. Such developing agents may be used alone or in combination of two or more, or may be used in the form of a precursor. These developers may be included in an appropriate layer of the photosensitive element or in an alkaline processing solution. Specific examples of the compound include aminophenols and pyrazolidinones. Among them, pyrazolidinones are particularly preferable because of less generation of stains.
For example, 1-phenyl-3-pyrazolidinone, 1-p-tolyl-4,4-dihydroxymethyl-3-pyrazolidinone, 1- (3′-methyl-phenyl) -4-methyl-4-hydroxymethyl-3-pyrazolidinone, 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidinone, 1-p-tolyl-4-methyl-4-hydroxymethyl-3-pyrazolidinone, and the like.
[0075]
As the development accelerator, amine, amino acid, polyethylene glycol, benzyl alcohol, dihydroxymethylbenzene and the like are used.
Any development inhibitor can be used, but a triazole derivative is preferred for the development of an autopositive emulsion combined with a nucleating agent, and a benztriazole derivative is particularly preferred.
As the antioxidant for preventing the deterioration of the developer, an arbitrary one having a reducing power for preventing the oxidation of the developer is used, but a sulfite, particularly potassium sulfite is preferably used.
As the gradation adjusting agent, hydroquinone derivatives and ascorbic acid derivatives are preferably used.
In addition, it is also preferable to add a transition metal salt, such as zinc nitrate, in order to enhance the temporal stability of the treatment liquid, or to add an aluminum salt to impart pH buffering properties.
[0076]
The treatment liquid can contain a light-shielding agent as necessary. In particular, in the case of an integrated photosensitive material that is exposed through a transparent support, it is necessary to impart light shielding properties to the processing solution.
For this purpose, carbon black and other pigments and dyes can be used as the light-shielding agent. In particular, when a dye image is observed with a white pigment contained in the treatment liquid and the developed treatment liquid layer as a background, it is preferable to use a pH-sensitive dye as the light-shielding agent.
[0077]
A development accelerator described in JP-A-62-215272, pages 72 to 91, a hardener described in pages 146 to 155, or a surfactant described in pages 201 to 210, in any of a photosensitive sheet, a cover sheet, and an alkali processing composition. Contains fluorine-containing compounds described on pages 210-222, thickeners described on pages 225-227, antistatic agents described on pages 227-230, polymer latex described on pages 230-239, matting agents described on page 240, and the like. Can do.
[0078]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to this.
Example-1
First, a method for preparing a silver halide emulsion will be described.
Emulsion silver halide emulsion grains [emulsions D-1 to D- differing in addition site and addition amount of emulsions A-1, Emulsion B, Emulsion C, and metal salts were prepared by the following emulsion grain preparation method. 5 (see Table 1)].
[0079]
[Table 1]

[0080]
Preparation of emulsion-A-1 (octahedral internal latent image type direct positive emulsion): (for comparison)
In 1000 ml of an aqueous gelatin solution containing 0.05 g of potassium bromide, 1 g of 3,6-dithia-1,8-octanediol, 0.034 mg of lead acetate and 60 g of deionized gelatin having a Ca content of 100 ppm or less, the temperature is raised to 75 ° C. While maintaining the addition rate of 0.4M silver nitrate aqueous solution and 0.4M potassium bromide aqueous solution by the control double jet method so that pBr becomes 1.60, 300 ml of silver nitrate aqueous solution is added for 40 minutes. Added over time.
When the addition was completed, octahedral silver bromide crystals (hereinafter referred to as core grains) having a uniform grain size with an average grain size (equivalent sphere diameter) of about 0.7 μm were produced.
Next, 1 mg of sodium thiosulfate, 90 mg of potassium tetrachloroaurate and 3 ml of an aqueous solution of lead acetate 4.1 mg and potassium bromide 1.2 g in 1000 ml of water are added to this preparation and heated at 75 ° C. for 80 minutes. Then, chemical sensitization treatment was performed. After 0.15M potassium bromide is added to the emulsion solution thus chemically sensitized, a 0.9M silver nitrate aqueous solution and a 0.9M aqueous solution are maintained while maintaining the temperature at 75 ° C., as in the preparation of the core grains. 670 ml of an aqueous silver nitrate solution was added over 70 minutes while adjusting the rate of addition of the aqueous potassium bromide solution so that the pBr was 1.30 by the control double jet method.
This emulsion is washed with water by a conventional flocculation method, and the above-mentioned gelatin, 2-phenoxyethanol and methyl P-hydroxybenzoate are added to obtain an average particle size (sphere equivalent diameter) of about 1.4 μm. Octahedral silver bromide crystals (hereinafter referred to as internal latent image type core / shell grains) were obtained.
Next, 3 ml of an aqueous solution in which 100 mg of sodium thiosulfate and 40 mg of sodium tetraborate are dissolved in 1000 ml of water is added to this internal latent image type core / shell emulsion, and 14 mg of poly (N-vinylpyrrolidone) is further added and heated at 60 ° C. After ripening, an octahedral internal latent image type direct positive emulsion was prepared by adding 0.005 M potassium bromide.
[0081]
Preparation of emulsion-B (octahedral internal latent image type direct positive emulsion):
In the preparation method of Emulsion-A, the addition time of the aqueous silver nitrate solution and the aqueous potassium bromide solution was changed, and the amount of the added chemical was changed, so that the average particle size (sphere equivalent diameter) was about 1.0 μm. An octahedral internal latent image type direct positive emulsion with a uniform thickness was obtained.
[0082]
Preparation of emulsion-C (octahedral internal latent image type direct positive emulsion):
In the preparation method of Emulsion-A, the addition time of the silver nitrate aqueous solution and the potassium bromide aqueous solution was changed, and the amount of the added chemical was changed, so that the average particle size (sphere equivalent diameter) was about 0.7 μm. An octahedral internal latent image type direct positive emulsion with a uniform thickness was obtained.
[0083]
Emulsion-D-1 (hexagonal plate internal latent image type direct positive emulsion) Preparation: (for comparison)
1.4M silver nitrate aqueous solution and 2M potassium bromide aqueous solution containing gelatin described above in 1.2 liters of gelatin aqueous solution containing 0.7% by weight of gelatin containing 0.05M potassium bromide and an average molecular weight of 100,000 or less While stirring vigorously, 33 ml of each was mixed simultaneously in 1 minute by the double jet method. During this period, the gelatin aqueous solution was kept at 30 ° C. Further, after adding 300 ml of a gelatin solution containing 10% by weight of deionized gelatin having a Ca content of 100 ppm or less, the temperature was raised to 75 ° C.
Next, 40 ml of a 0.9 M silver nitrate aqueous solution was added over 3 minutes, and then a 25 wt% aqueous ammonia solution was added, followed by aging at 75 ° C. After ripening, after neutralizing ammonia, double the 1M silver nitrate aqueous solution and 1M potassium bromide aqueous solution at an accelerated flow rate with a pBr of 2.5 (the flow rate at the end is 6 times the flow rate at the start). Added by jet method. (The amount of silver nitrate aqueous solution used was 500 ml.)
The particles thus formed (hereinafter referred to as core particles) were washed with water by a conventional flocculation method, and gelatin, 2-phenoxyethanol and methyl P-hydroxybenzoate were added to obtain 750 g of hexagonal tabular core particles. Obtained.
The obtained hexagonal tabular core particles had an average projected area equivalent circle diameter of 0.9 μm, an average thickness of 0.20 μm, and 95% of the total projected area was occupied by hexagonal tabular grains.
Next, 1300 cc of water, 0.11 M of potassium bromide and 40 g of deionized gelatin were added to 200 g of the hexagonal tabular core emulsion, the temperature was raised to 75 ° C., and 3,6-dithia-1,8-octanediol was added. Chemical sensitization was performed by adding 2.4 g of an aqueous solution prepared by dissolving 0.3 g of sodium benzenethiosulfate 10 mg and potassium tetrachloroaurate 90 mg and potassium bromide 1.2 g in water 1000 ml and heating at 75 ° C. for 180 minutes. It was. Addition of 2M aqueous silver nitrate solution and 2.5M aqueous potassium bromide solution to the core particles thus chemically sensitized so that the pBr is 2.5. While adjusting the amount and the addition rate, the addition was carried out by the double jet method at an accelerated flow rate (the flow rate at the end was 3 times the flow rate at the start). (The amount of silver nitrate aqueous solution used was 810 ml.)
After adding 0.3 M potassium bromide, the emulsion was washed with water by a conventional flocculation method, and gelatin was added. Thus, a hexagonal plate-like internal latent image type core / shell emulsion was obtained. The obtained hexagonal tabular grains had an average projected area equivalent circle diameter of 2.5 μm, an average thickness of 0.37 μm, and an average volume size of 1.4 (μm). ^Three And 88% of the total projected area was occupied by hexagonal tabular grains.
Next, 15 ml of an aqueous solution prepared by dissolving 100 mg of sodium thiosulfate and 40 mg of sodium tetraborate in 1000 ml of water was added to the hexagonal plate-like internal latent image type core / shell emulsion, and 20 mg of poly (N-vinylpyrrolidone) was further added. The grain surface was chemically sensitized by heating at 100 ° C. for 100 minutes to prepare a hexagonal tabular internal latent image type direct positive emulsion D-1.
[0084]
Emulsion-D-2 (hexagonal plate internal latent image type direct positive emulsion) Preparation: (for comparison)
1.4M silver nitrate aqueous solution and 2M potassium bromide aqueous solution containing gelatin described above in 1.2 liters of gelatin aqueous solution containing 0.7% by weight of gelatin containing 0.05M potassium bromide and an average molecular weight of 100,000 or less While stirring vigorously, 33 ml of each was mixed simultaneously in 1 minute by the double jet method. During this period, the gelatin aqueous solution was kept at 30 ° C. Further, after adding 300 ml of a gelatin solution containing 10% by weight of deionized gelatin having a Ca content of 100 ppm or less, the temperature was raised to 75 ° C.
Next, 40 ml of a 0.9 M silver nitrate aqueous solution was added over 3 minutes, and then a 25 wt% aqueous ammonia solution was added, followed by aging at 75 ° C. After ripening, after neutralizing ammonia, 1M silver nitrate aqueous solution and 1M potassium bromide aqueous solution were accelerated at a flow rate of pBr of 2.5 (the flow rate at the end was 6 times the flow rate at the start). Added by double jet method. (The amount of silver nitrate aqueous solution used was 500 ml.)
The particles thus formed (hereinafter referred to as core particles) were washed with water by a conventional flocculation method, and gelatin, 2-phenoxyethanol and methyl P-hydroxybenzoate were added to obtain 750 g of hexagonal tabular core particles. Obtained.
The obtained hexagonal tabular core particles had an average projected area equivalent circle diameter of 0.9 μm, an average thickness of 0.20 μm, and 95% of the total projected area was occupied by hexagonal tabular grains.
Next, 1300 ml of water, 0.11 M of potassium bromide and 40 g of deionized gelatin were added to 200 g of the hexagonal tabular core emulsion, the temperature was raised to 75 ° C., and 3,6-dithia-1,8-octanediol was added. .3 g, sodium benzenethiosulfate 10 mg, 2.4 cc of an aqueous solution prepared by dissolving 90 mg of potassium tetrachloroaurate and 1.2 g of potassium bromide in 1000 mg of water, and 15 mg of lead acetate (added in an aqueous solution) were added at 180.degree. Chemical sensitization was performed by heating for a minute. Addition of 2M aqueous silver nitrate solution and 2.5M aqueous potassium bromide solution to the core particles thus chemically sensitized so that the pBr is 2.5. While adjusting the speed, it was added by the double jet method at an accelerated flow rate (the flow rate at the end was 3 times the flow rate at the start). (The amount of silver nitrate aqueous solution used was 810 ml.)
After adding 0.3 M potassium bromide, the emulsion was washed with water by a conventional flocculation method, and gelatin was added. Thus, a hexagonal plate-like internal latent image type core / shell emulsion was obtained. The obtained hexagonal tabular grains had an average projected area equivalent circle diameter of 2.5 μm, an average thickness of 0.37 μm, and an average volume size of 1.4 (μm). ^Three And 88% of the total projected area was occupied by hexagonal tabular grains.
Next, 15 ml of an aqueous solution prepared by dissolving 100 mg of sodium thiosulfate and 40 mg of sodium tetraborate in 1000 ml of water was added to the hexagonal plate-like internal latent image type core / shell emulsion, and 20 mg of poly (N-vinylpyrrolidone) was further added. The grain surface was chemically sensitized by heating at 100 ° C. for 100 minutes to prepare a hexagonal tabular internal latent image type direct positive emulsion D-2.
[0085]
Emulsion-D-3 (hexagonal tabular internal latent image type direct positive emulsion) Preparation: (Invention)
1.4M silver nitrate aqueous solution and 2M potassium bromide aqueous solution containing gelatin described above in 1.2 liters of gelatin aqueous solution containing 0.7% by weight of gelatin containing 0.05M potassium bromide and an average molecular weight of 100,000 or less While stirring vigorously, 33 ml of each was mixed simultaneously in 1 minute by the double jet method. During this period, the gelatin aqueous solution was kept at 30 ° C. Further, after adding 300 ml of a gelatin solution containing 10% by weight of deionized gelatin having a Ca content of 100 ppm or less, the temperature was raised to 75 ° C.
Next, 40 ml of a 0.9 M silver nitrate aqueous solution was added over 3 minutes, and then a 25 wt% aqueous ammonia solution was added, followed by aging at 75 ° C. After completion of ripening, after neutralizing ammonia, 5 mg of lead acetate (added in an aqueous solution) was added, and an accelerated flow rate with a 1M silver nitrate aqueous solution and a 1M potassium bromide aqueous solution with pBr of 2.5 (at the end) The flow rate was 6 times the starting flow rate) and added by the double jet method. (The amount of silver nitrate aqueous solution used was 500 ml.)
The particles thus formed (hereinafter referred to as core particles) were washed with water by a conventional flocculation method, and gelatin, 2-phenoxyethanol and methyl P-hydroxybenzoate were added to obtain 750 g of hexagonal tabular core particles. Obtained.
The obtained hexagonal tabular core particles had an average projected area equivalent circle diameter of 0.9 μm, an average thickness of 0.20 μm, and 95% of the total projected area was occupied by hexagonal tabular grains.
Next, 1300 ml of water, 0.11 M of potassium bromide and 40 g of deionized gelatin were added to 200 g of the hexagonal tabular core emulsion, the temperature was raised to 75 ° C., and 3,6-dithia-1,8-octanediol was added. .3 g, sodium benzenethiosulfate 10 mg, 2.4 ml of an aqueous solution prepared by dissolving 90 mg of potassium tetrachloroaurate and 1.2 g of potassium bromide in 1000 ml of water, and 15 mg of lead acetate (added in an aqueous solution) were added at 180.degree. Chemical sensitization was performed by heating for a minute. Addition of 2M aqueous silver nitrate solution and 2.5M aqueous potassium bromide solution to the core particles thus chemically sensitized so that the pBr is 2.5. While adjusting the speed, it was added by the double jet method at an accelerated flow rate (the flow rate at the end was 3 times the flow rate at the start). (The amount of silver nitrate aqueous solution used was 810 ml.)
After adding 0.3 M potassium bromide, the emulsion was washed with water by a conventional flocculation method, and gelatin was added. Thus, a hexagonal plate-like internal latent image type core / shell emulsion was obtained. The obtained hexagonal tabular grains had an average projected area equivalent circle diameter of 2.5 μm, an average thickness of 0.37 μm, and an average volume size of 1.4 (μm). ^Three And 88% of the total projected area was occupied by hexagonal tabular grains.
Next, 15 ml of an aqueous solution prepared by dissolving 100 mg of sodium thiosulfate and 40 mg of sodium tetraborate in 1000 ml of water was added to the hexagonal plate-like internal latent image type core / shell emulsion, and 20 mg of poly (N-vinylpyrrolidone) was further added. The grain surface was chemically sensitized by heating at 0 ° C. for 100 minutes to prepare a hexagonal tabular internal latent image type direct positive emulsion D-3.
[0086]
Emulsion-D-4 (hexagonal tabular internal latent image type direct positive emulsion) Preparation: (Invention)
1.4M silver nitrate aqueous solution and 2M potassium bromide aqueous solution containing gelatin described above in 1.2 liters of gelatin aqueous solution containing 0.7% by weight of gelatin containing 0.05M potassium bromide and an average molecular weight of 100,000 or less While stirring vigorously, 33 ml of each was mixed simultaneously in 1 minute by the double jet method. During this period, the gelatin aqueous solution was kept at 30 ° C. Further, after adding 300 ml of a gelatin solution containing 10% by weight of deionized gelatin having a Ca content of 100 ppm or less, the temperature was raised to 75 ° C.
Next, 40 ml of a 0.9 M silver nitrate aqueous solution was added over 3 minutes, and then a 25 wt% aqueous ammonia solution was added, followed by aging at 75 ° C. After completion of ripening, neutralize ammonia, add 500 mg of lead acetate (added in aqueous solution), add 1M silver nitrate aqueous solution and 1M potassium bromide aqueous solution while accelerating the flow rate with 2.5 pBr (at the end) The flow rate was 6 times the starting flow rate) and added by the double jet method. (The amount of silver nitrate aqueous solution used was 500 ml.)
The particles thus formed (hereinafter referred to as core particles) were washed with water by a conventional flocculation method, and gelatin, 2-phenoxyethanol and methyl P-hydroxybenzoate were added to obtain 750 g of hexagonal tabular core particles. Obtained.
The obtained hexagonal tabular core particles had an average projected area equivalent circle diameter of 0.9 μm, an average thickness of 0.20 μm, and 95% of the total projected area was occupied by hexagonal tabular grains.
Next, 1300 ml of water, 0.11 M of potassium bromide and 40 g of deionized gelatin were added to 200 g of the hexagonal tabular core emulsion, the temperature was raised to 75 ° C., and 3,6-dithia-1,8-octanediol was added. .3 g, sodium benzenethiosulfate 10 mg, 2.4 ml of an aqueous solution prepared by dissolving 90 mg of potassium tetrachloroaurate and 1.2 g of potassium bromide in 1000 ml of water, and 150 mg of lead acetate (added in an aqueous solution) were added at 180.degree. Chemical sensitization was performed by heating for a minute. Addition of 2M aqueous silver nitrate solution and 2.5M aqueous potassium bromide solution to the core particles thus chemically sensitized so that the pBr is 2.5. While adjusting the speed, it was added by the double jet method at an accelerated flow rate (the flow rate at the end was 3 times the flow rate at the start). (The amount of silver nitrate aqueous solution used was 810 ml.)
After adding 0.3 M potassium bromide, the emulsion was washed with water by a conventional flocculation method, and gelatin was added. Thus, a hexagonal plate-like internal latent image type core / shell emulsion was obtained. The obtained hexagonal tabular grains had an average projected area equivalent circle diameter of 2.5 μm, an average thickness of 0.37 μm, and an average volume size of 1.4 (μm). ^Three And 88% of the total projected area was occupied by hexagonal tabular grains.
Next, 15 ml of an aqueous solution prepared by dissolving 100 mg of sodium thiosulfate and 40 mg of sodium tetraborate in 1000 ml of water was added to the hexagonal plate-like internal latent image type core / shell emulsion, and 20 mg of poly (N-vinylpyrrolidone) was further added. The grain surface was chemically sensitized by heating at 0 ° C. for 100 minutes to prepare a hexagonal tabular internal latent image type direct positive emulsion D-4.
[0087]
Emulsion-D-5 (hexagonal plate internal latent image type direct positive emulsion) Preparation: (Invention)
1.4M silver nitrate aqueous solution and 2M potassium bromide aqueous solution containing gelatin described above in 1.2 liters of gelatin aqueous solution containing 0.7% by weight of gelatin containing 0.05M potassium bromide and an average molecular weight of 100,000 or less While stirring vigorously, 33 ml of each was mixed simultaneously in 1 minute by the double jet method. During this period, the gelatin aqueous solution was kept at 30 ° C. Further, after adding 300 ml of a gelatin solution containing 10% by weight of deionized gelatin having a Ca content of 100 ppm or less, the temperature was raised to 75 ° C.
Next, 40 ml of a 0.9 M silver nitrate aqueous solution was added over 3 minutes, and then a 25 wt% aqueous ammonia solution was added, followed by aging at 75 ° C. After ripening, after neutralizing ammonia, 3.6 mg of cadmium nitrate (added in aqueous solution) was added, and the flow rate was accelerated while 1M silver nitrate aqueous solution and 1M potassium bromide aqueous solution were kept at pBr of 2.5. The flow rate at the time was 6 times the flow rate at the beginning) and was added by the double jet method. (The amount of silver nitrate aqueous solution used was 500 ml.)
The particles thus formed (hereinafter referred to as core particles) were washed with water by a conventional flocculation method, and gelatin, 2-phenoxyethanol and methyl P-hydroxybenzoate were added to obtain 750 g of hexagonal tabular core particles. Obtained.
The obtained hexagonal tabular core particles had an average projected area equivalent circle diameter of 0.9 μm, an average thickness of 0.20 μm, and 95% of the total projected area was occupied by hexagonal tabular grains.
Next, 1300 ml of water, 0.11 M of potassium bromide and 40 g of deionized gelatin were added to 200 g of the hexagonal tabular core emulsion, the temperature was raised to 75 ° C., and 3,6-dithia-1,8-octanediol was added. .3 g, sodium benzenethiosulfate 10 mg, 2.4 ml of an aqueous solution prepared by dissolving 90 mg of potassium tetrachloroaurate and 1.2 g of potassium bromide in 1000 ml of water, and 11 mg of cadmium nitrate (added in an aqueous solution) were added at 180.degree. Chemical sensitization was performed by heating for a minute. Addition of 2M aqueous silver nitrate solution and 2.5M aqueous potassium bromide solution to the core particles thus chemically sensitized so that the pBr is 2.5. While adjusting the speed, it was added by the double jet method at an accelerated flow rate (the flow rate at the end was 3 times the flow rate at the start). (The amount of silver nitrate aqueous solution used was 810 ml.)
After adding 0.3 M potassium bromide, the emulsion was washed with water by a conventional flocculation method, and gelatin was added. Thus, a hexagonal plate-like internal latent image type core / shell emulsion was obtained. The obtained hexagonal tabular grains had an average projected area equivalent circle diameter of 2.5 μm, an average thickness of 0.37 μm, and an average volume size of 1.4 (μm). ^Three And 88% of the total projected area was occupied by hexagonal tabular grains.
Next, 15 ml of an aqueous solution prepared by dissolving 100 mg of sodium thiosulfate and 40 mg of sodium tetraborate in 1000 ml of water was added to the hexagonal plate-like internal latent image type core / shell emulsion, and 20 mg of poly (N-vinylpyrrolidone) was further added. The grain surface was chemically sensitized by heating at 100 ° C. for 100 minutes to prepare a hexagonal tabular internal latent image type direct positive emulsion D-5.
[0088]
Using these emulsions, a comparative photosensitive element (Sample 101) having the constitution shown in Table 2 was prepared.
[0089]
[Table 2]

[0090]
[Table 3]

[0091]
[Table 4]

[0092]
[Table 5]

[0093]
[Table 6]

[0094]
[Table 7]

[0095]
[Table 8]

[0096]
[Formula 4]

[0097]
[Chemical formula 5]

[0098]
[Chemical 6]

[0099]
[Chemical 7]

[0100]
[Chemical 8]

[0101]
[Chemical 9]

[0102]
The cover sheet was prepared as follows.
The following layers were coated on a transparent polyethylene terephthalate support containing gelatin-primed light piping anti-piping dye.
(1) 10.4 g / m of acrylic acid-butyl acrylate (molar ratio 8: 2) copolymer having an average molecular weight of 50,000 ² And 1,4-bis (2,3-epoxypropoxy) -butane 0.1 g / m ² Neutralization layer containing.
(2) 4.3 g / m of acetylcellulose having an oxidation degree of 51% ² , Poly (methyl vinyl ether-co-monomethyl maleate) 0.2 g / m ² Including a neutralization timing layer.
(3) Weight of polymer latex obtained by emulsion polymerization of styrene-butyl acrylate-acrylic acid-N methylol acrylamide at a weight ratio of 49.7 / 42.3 / 4/4 and methyl methacrylate / acrylic acid / N-methylol acrylamide A polymer latex emulsion-polymerized at a ratio of 93 to 3 to 4 was blended so that the solid content ratio was 6 to 4, and the total solid content was 2.5 g / m. ² Including layers.
(4) Gelatin 1g / m ² Including layers.
[0103]
The alkali treatment composition was prepared by the following method.
A container that can be broken by pressure was filled with 0.8 g of a treatment liquid having the following composition.
1-p-Tolyl-4-hydroxymethyl-4-methyl
-3-pyrazolidone 10.0 g
Methyl hydroquinone 0.18g
5-methylbenzotriazole 3.0 g
Sodium sulfite (anhydrous) 0.2g
Benzyl alcohol 1.5ml
Carboxymethylcellulose Na salt 58g
150g carbon black
200 ml of potassium hydroxide (28% aqueous solution)
680 ml of water
[0104]
Next, the emulsions of the eighth layer, the fifteenth layer, and the twenty-second layer are changed to emulsions D-2, D-3, D-4, D-5, and A-1 shown in Table 1, and Table 3 Samples 102, 103, 104, 105, and 201 shown in FIG.
[0105]
[Table 9]

[0106]
The photosensitive elements 101 to 105 and 201 are subjected to the following three storage conditions A, B, and C.
Storage condition A: 3 days freezing
Storage condition B: 50 ° C, 30%, 3 days
Storage condition C: 45 ° C, 70%, 3 days
After being stored in the above, after being exposed from the emulsion layer side through a gray continuous wedge, it was superimposed on the cover sheet, and the processing solution was developed between both materials using a pressure roller to a thickness of 75 μm. . The exposure was performed by adjusting the exposure illuminance so that the exposure amount was constant. The treatment was performed at 25 ° C., and the transfer density was measured with a color densitometer after 10 minutes. The results are shown in Table 4. However, the midpoint sensitivity shown here represents the reciprocal value of the exposure amount giving an intermediate density between the maximum density and the minimum density as a relative value with respect to the reference sample. In addition, the low density sensitivity represents an inverse value of the exposure amount giving a density corresponding to the minimum density +0.2 as a relative value with respect to the reference sample.
[0107]
[Table 10]

[0108]
From Table 4, the samples 103, 104, and 105 of the present invention are higher in both the midpoint sensitivity and the lower concentration sensitivity than the comparative samples 101, 102, and 201, and the decrease in the maximum concentration under high humidity storage is small. It is clear that the desensitization at
[0109]
【The invention's effect】
It was found that an image having high sensitivity and excellent storage stability can be obtained by the present invention.

Claims (4)

Including tabular silver halide grains having an average grain diameter of 0.3 μm or more and an aspect ratio (equivalent circle diameter / grain thickness of silver halide grains) of 2 or more and 100 or less of 50% or more of the total silver halide grain projected area, and Cr, Mn, Cu, Zn, Cd, Pb, Bi, also saw including at least one metal ion of the Re and the periodic table group 8 metal and lanthanide to any of the core portion and the shell portion, the core portion An internal latent image type direct positive silver halide emulsion characterized in that the concentration of metal ions incorporated in the shell is equal to or greater than the concentration of metal ions incorporated in the shell portion . Claim 1 Symbol placement, wherein the metal ion concentration incorporated is less than the core portion and both shell parts 1.0 × 10 ^-6 mol / mol Ag or more 1.0 × 10 ^-2 mol / mol Ag Internal latent image type direct positive silver halide emulsion. 3. The internal latent image type direct positive silver halide emulsion according to claim 1, wherein the incorporated metal ion species is Pb. Having at least one light-sensitive silver halide emulsion layer combined with a dye image-forming material on the support, the dye image-forming material being diffused in connection with silver development represented by the following general formula (I) non-diffusible compounds releasing sex dye or a precursor or it in the diffusion of itself is a compound that changes color diffusion transfer light-sensitive material, at least one layer of said silver halide emulsion layer, claims 1 3 A color diffusion transfer photosensitive material comprising the internal latent image type direct positive silver halide emulsion described above.
Formula (I)
(DYE-Y) nZ
{DYE represents a dye group, a temporarily shortened dye group or a dye precursor group, Y represents a simple bond or linking group, and Z corresponds to or is opposite to a photosensitive silver salt having a latent image in an image form. Correspondingly, a difference is caused in the diffusivity of the compound represented by the general formula (I), or DYE is released, and the diffusivity between the released DYE and the compound represented by the general formula (I) Represents a group having such a property as to cause a difference, n represents 1 or 2, and when n is 2, two DYE-Ys may be the same or different. }