JP3780720B2 - X-ray image recording method - Google Patents

Description

【００５２】
式中、Ｒは水素原子または炭素原子数１〜１０のアルキル基（例えばブチル基、２，４，４−トリメチルペンチル基等）を表し、Ｒ′及びＲ″は炭素原子数１〜５のアルキル基（例えばメチル基、エチル基、ｔ−ブチル基等）を表す。
【００５３】
一般式（Ａ）で表される化合物の具体例を以下に示す。但し、本発明はこれらに限定されない。
【００５４】
【化２】

【００５５】
【化３】

【００５６】
前記一般式（Ａ）で表される化合物を始めとする還元剤の使用量は好ましくは銀１モル当り１×１０^-2〜１０モル、特に１×１０^-2〜１．５モルである。
【００５７】
本発明においては、感光性層側にマット剤を含有することが好ましく、熱現像後の画像の傷つき防止のためには、感光材料の表面にマット剤を配することが好ましく、そのマット剤を乳剤層側の全バインダーに対し、重量比で０．５〜１０％含有することが好ましい。
【００５８】
本発明に用いられるマット剤の材質は、有機物及び無機物のいずれでもよい。例えば、無機物としては、スイス特許第３３０，１５８号等に記載のシリカ、仏国特許第１，２９６，９９５号等に記載のガラス粉、英国特許第１，１７３，１８１号等に記載のアルカリ土類金属またはカドミウム、亜鉛等の炭酸塩等をマット剤として用いることができる。有機物としては、米国特許第２，３２２，０３７号等に記載の澱粉、ベルギー特許第６２５，４５１号や英国特許第９８１，１９８号等に記載された澱粉誘導体、特公昭４４−３６４３号等に記載のポリビニルアルコール、スイス特許第３３０，１５８号等に記載のポリスチレン或いはポリメタアクリレート、米国特許第３，０７９，２５７号等に記載のポリアクリロニトリル、米国特許第３，０２２，１６９号等に記載されたポリカーボネートの様な有機マット剤を用いることができる。
【００５９】
マット剤の形状は、定形、不定形どちらでも良いが、好ましくは定形で、球形が好ましく用いられる。マット剤の大きさはマット剤の体積を球形に換算したときの直径で表される。本発明においてマット剤の粒径とはこの球形換算した直径のことを示すものとする。
【００６０】
本発明に用いられるマット剤は、平均粒径が０．５μｍ〜１０μｍであることが好ましく、更に好ましくは１．０μｍ〜８．０μｍである。又、粒子サイズ分布の変動係数としては、５０％以下であることが好ましく、更に好ましくは４０％以下であり、特に好ましくは３０％以下となるマット剤である。
【００６１】
ここで、粒子サイズ分布の変動係数は、下記の式で表される値である。
【００６２】
（粒径の標準偏差）／（粒径の平均値）×１００
本発明に用いられるマット剤は任意の構成層中に含むことができるが、本発明の目的を達成するためには好ましくは感光性層以外の構成層であり、更に好ましくは支持体から見て最も外側の層である。
【００６３】
本発明に用いられるマット剤の添加方法は、予め塗布液中に分散させて塗布する方法であってもよいし、塗布液を塗布した後、乾燥が終了する以前にマット剤を噴霧する方法を用いてもよい。また複数の種類のマット剤を添加する場合は、両方の方法を併用してもよい。
【００６４】
本発明に用いられる熱現像感光材料は、熱現像処理にて写真画像を形成するもので、還元可能な非感光性の銀源（有機銀塩）、触媒活性量の感光性ハロゲン化銀、ヒドラジン誘導体、還元剤、及び必要に応じて銀の色調を抑制する色調剤を通常（有機）バインダーマトリックス中に分散した状態で含有している熱現像感光材料であることが好ましい。本発明に用いられる熱現像感光材料は常温で安定であるが、露光後高温（例えば、８０℃〜１４０℃）に加熱することで現像される。加熱することで有機銀塩（酸化剤として機能する）と還元剤との間の酸化還元反応を通じて銀を生成する。この酸化還元反応は露光でハロゲン化銀に発生した潜像の触媒作用によって促進される。露光領域中の有機銀塩の反応によって生成した銀は黒色画像を提供し、これは非露光領域と対照をなし、画像の形成がなされる。この反応過程は外部から水等の処理液を供給することなしで進行する。
【００６５】
本発明に用いられる熱現像感光材料は支持体上に少なくとも一層の感光性層を有している。支持体の上に感光性層のみを形成しても良いが、感光性層の上に少なくとも１層の非感光性層を形成することが好ましい。感光性層に通過する光の量または波長分布を制御するために感光性層と同じ側または反対側にフィルター層を形成しても良いし、感光性層に染料または顔料を含ませても良い。染料としては特願平７−１１１８４号の化合物が好ましい。感光性層は複数層にしても良く、また階調の調節のため感度を高感層／低感層または低感層／高感層にしても良い。各種の添加剤は感光性層、非感光性層、またはその他の形成層のいずれに添加しても良い。本発明に用いられる熱現像感光材料には例えば、界面活性剤、酸化防止剤、安定化剤、可塑剤、紫外線吸収剤、被覆助剤等を用いても良い。
【００６６】
本発明に用いられる熱現像感光材料には、色調剤を添加することが好ましい。色調剤は、米国特許第３，０８０，２５４号、同第３，８４７，６１２号および同第４，１２３，２８２号に示されるように、写真技術において周知の材料である。好適な色調剤の例はＲｅｓｅａｒｃｈ Ｄｉｓｃｌｏｓｕｒｅ第１７０２９号に開示されており、次のものがある。
【００６７】
イミド類（例えば、フタルイミド）；環状イミド類、ピラゾリン−５−オン類、及びキナゾリノン（例えば、スクシンイミド、３−フェニル−２−ピラゾリン−５−オン、１−フェニルウラゾール、キナゾリン及び２，４−チアゾリジンジオン）；ナフトールイミド類（例えば、Ｎ−ヒドロキシ−１，８−ナフトールイミド）；コバルト錯体（例えば、コバルトのヘキサミントリフルオロアセテート）、メルカプタン類（例えば、３−メルカプト−１，２，４−トリアゾール）；Ｎ−（アミノメチル）アリールジカルボキシイミド類（例えば、Ｎ−（ジメチルアミノメチル）フタルイミド）；ブロックされたピラゾール類、イソチウロニウム（ｉｓｏｔｈｉｕｒｏｎｉｕｍ）誘導体及びある種の光漂白剤の組み合わせ（例えば、Ｎ，Ｎ′−ヘキサメチレン（１−カルバモイル−３，５−ジメチルピラゾール）、１，８−（３，６−ジオキサオクタン）ビス（イソチウロニウムトリフルオロアセテート）、及び２−（トリブロモメチルスルホニル）ベンゾチアゾールの組み合わせ）；メロシアニン染料（例えば、３−エチル−５−（（３−エチル−２−ベンゾチアゾリニリデン（ベンゾチアゾリニリデン））−１−メチルエチリデン）−２−チオ−２，４−オキサゾリジンジオン）；フタラジノン、フタラジノン誘導体またはこれらの誘導体の金属塩（例えば、４−（１−ナフチル）フタラジノン、６−クロロフタラジノン、５，７−ジメチルオキシフタラジノン、及び２，３−ジヒドロ−１，４−フタラジンジオン）；フタラジノンとスルフィン酸誘導体の組み合わせ（例えば、６−クロロフタラジノン＋ベンゼンスルフィン酸ナトリウムまたは８−メチルフタラジノン＋ｐ−トリスルホン酸ナトリウム）；フタラジン＋フタル酸の組み合わせ；フタラジン（フタラジンの付加物を含む）とマレイン酸無水物、及びフタル酸、２，３−ナフタレンジカルボン酸またはｏ−フェニレン酸誘導体及びその無水物（例えば、フタル酸、４−メチルフタル酸、４−ニトロフタル酸及びテトラクロロフタル酸無水物）から選択される少なくとも１つの化合物との組み合わせ；キナゾリンジオン類、ベンズオキサジン、ナルトキサジン誘導体；ベンズオキサジン−２，４−ジオン類（例えば、１，３−ベンズオキサジン−２，４−ジオン）；ピリミジン類及び不斉−トリアジン類（例えば、２，４−ジヒドロキシピリミジン）、及びテトラアザペンタレン誘導体（例えば、３，６−ジメルカプト−１，４−ジフェニル−１Ｈ，４Ｈ−２，３ａ，５，６ａ−テトラアザペンタレン）。好ましい色調剤としてはフタラゾンまたはフタラジンである。
【００６８】
本発明には現像を抑制あるいは促進させ現像を制御するため、分光増感効率を向上させるため、現像前後の保存性を向上させるため等にメルカプト化合物、ジスルフィド化合物、チオン化合物を含有させることができる。本発明にメルカプト化合物を使用する場合、いかなる構造のものでもよいが、ＡｒＳＭ、Ａｒ−Ｓ−Ｓ−Ａｒで表されるものが好ましい。式中、Ｍは水素原子またはアルカリ金属原子であり、Ａｒは１個以上の窒素、イオウ、酸素、セレニウムまたはテルリウム原子を有する芳香環または縮合芳香環である。好ましくは、複素芳香環はベンズイミダゾール、ナフトイミダゾール、ベンゾチアゾール、ナフトチアゾール、ベンズオキサゾール、ナフトオキサゾール、ベンゾセレナゾール、ベンゾテルゾール、イミダゾール、オキサゾール、ピラゾール、トリアゾール、チアジアゾール、テトラゾール、トリアジン、ピリミジン、ピリダジン、ピラジン、ピリジン、プリン、キノリンまたはキナゾリノンである。この複素芳香環は、例えば、ハロゲン原子（例えば、ＢｒおよびＣｌ）、ヒドロキシル基、アミノ基、カルボキシル基、アルキル基（例えば、１個以上の炭素原子、好ましくは１〜４個の炭素原子を有するもの）およびアルコキシル基（例えば、１個以上の炭素原子、好ましくは１〜４個の炭素原子を有するもの）からなる置換基群から選択されるものを有してもよい。メルカプト置換複素芳香族化合物としては、２−メルカプトベンズイミダゾール、２−メルカプトベンズオキサゾール、２−メルカプトベンゾチアゾール、２−メルカプト−５−メチルベンズイミダゾール、６−エトキシ−２−メルカプトベンゾチアゾール、２，２’−ジチオビスベンゾチアゾール、３−メルカプト−１，２，４−トリアゾール、４，５−ジフェニル−２−イミダゾールチオール、２−メルカプトイミダゾール、１−エチル−２−メルカプトベンズイミダゾール、２−メルカプトキノリン、８−メルカプトプリン、２−メルカプト−４−（３Ｈ）キナゾリノン、７−トリフルオロメチル−４−キノリンチオール、２，３，５，６−テトラクロロ−４−ピリジンチオール、４−アミノ−６−ヒドロキシ−２−メルカプトピリミジンモノヒドレート、２−アミノ−５−メルカプト−１，３，４−チアジアゾール、３−アミノ−５−メルカプト−１，２，４−トリアゾール、４−ヒドロキシ−２−メルカプトピリミジン、２−メルカプトピリミジン、４，６−ジアミノ−２メルカプトピリミジン、２−メルカプト−４−メチルピリミジンヒドロクロリド、３−メルカプト−５−フェニル−１，２，４−トリアゾール、２−メルカプト−４−フェニルオキサゾール等が挙げられるが、本発明はこれらに限定されない。
【００６９】
上記記載のメルカプト化合物の添加量としては乳剤層中に銀１モル当たり０．００１〜１．０モルが好ましく、さらに好ましくは、銀の１モル当たり０．０１〜０．３モルである。
【００７０】
最も有効なカブリ防止剤として知られているものは水銀イオンである。感光材料中にカブリ防止剤として水銀化合物を使用することについては、例えば米国特許第３，５８９，９０３号に開示されている。しかし、水銀化合物は環境的に好ましくない。非水銀カブリ防止剤としては例えば米国特許第４，５４６，０７５号及び同第４，４５２，８８５号及び特開昭５９−５７２３４号に開示されている様なカブリ防止剤が好ましい。
【００７１】
特に好ましい非水銀カブリ防止剤としては、米国特許第３，８７４，９４６号及び同第４，７５６，９９９号に開示されているような化合物、−Ｃ（Ｘ₁）（Ｘ₂）（Ｘ₃）（ここでＸ₁及びＸ₂はハロゲン原子を表し、Ｘ₃は水素またはハロゲン原子を表す）で表される置換基を１以上備えたヘテロ環状化合物が挙げられる。好適なカブリ防止剤の例としては、特開平９−９０５５０号段落番号〔００６２〕〜〔００６３〕に記載されている化合物等が好ましく用いられる。
【００７２】
更に、より好適なカブリ防止剤は米国特許第５，０２８，５２３号及び欧州特許第６００，５８７号、同第６０５，９８１号、同第６３１，１７６号等に開示されている。
【００７３】
本発明における感光層には、可塑剤および潤滑剤として多価アルコール（例えば、米国特許第２，９６０，４０４号に記載された種類のグリセリンおよびジオール）、同第２，５８８，７６５号および同第３，１２１，０６０号に記載の脂肪酸またはエステル、英国特許第９５５，０６１号に記載のシリコーン樹脂等を用いることができる。
【００７４】
本発明に用いられる感光層、保護層、バック層等各層には硬膜剤を用いてもよい、硬膜剤の例としては、イソシアネート化合物類、米国特許第４，７９１，０４２号等に記載されているエポキシ化合物類、特開昭６２−８９０４８号等に記載されているビニルスルホン系化合物類等が用いられる。
【００７５】
本発明には塗布性、帯電改良等を目的として界面活性剤を用いてもよい。界面活性剤の例としては、アニオン系、カチオン系、ベタイン系、ノニオン系、フッ素系等いかなるものも適宜用いられる。具体的には、特開昭６２−１７０９５０号、米国特許第５，３８２，５０４号等に記載のフッ素系高分子界面活性剤、特開昭６０−２４４９４５号、特開昭６３−１８８１３５号等に記載のフッ素系界面活性剤、米国特許第３，８８５，９６５号等に記載のポリシロキサン系界面活性剤、特開平６−３０１１４０号等に記載のポリアルキレンオキサイドやアニオン系界面活性剤等が挙げられる。
【００７６】
本発明における熱現像用写真乳剤は、ディップ塗布法、エアナイフ塗布法、フロー塗布法、または米国特許第２，６８１，２９４号に記載の種類のホッパーを用いる押出塗布法を含む種々の塗布方法を用いることができる。必要により、米国特許第２，７６１，７９１号および英国特許第８３７，０９５号に記載の方法により２層またはそれ以上の層を同時に塗布することができる。
【００７７】
本発明で用いられる支持体は、現像処理後に所定の光学濃度を得るため，及び現像処理後の画像の変形を防ぐためにプラスチックフイルム（例えば、ポリエチレンテレフタレート、ポリカーボネート、ポリイミド、ナイロン、セルローストリアセテート、ポリエチレンナフタレート）であることが好ましい。
【００７８】
その中でも好ましい支持体としては、ポリエチレンテレフタレート（以下ＰＥＴと略す）、ポリエチレンナフタレート（以下ＰＥＮと略す）、及びシンジオタクチック構造を有するスチレン系重合体を含むプラスチック（以下ＳＰＳと略す）の支持体が挙げられる。支持体の厚みとしては５０〜３００μｍ程度、好ましくは７０〜１８０μｍである。
【００７９】
また熱処理したプラスチック支持体を用いることもできる。採用するプラスチックとしては、前記のプラスチックが挙げられる。支持体の熱処理とはこれらの支持体を製膜後、感光性層が塗布されるまでの間に、支持体のガラス転移点より３０℃以上高い温度で、好ましくは３５℃以上高い温度で、更に好ましくは４０℃以上高い温度で加熱することがよい。但し、支持体の融点を超えた温度で加熱しては本発明の効果は得られない。
【００８０】
次に用いられるプラスチックについて説明する。
【００８１】
ＰＥＴはポリエステルの成分が全てポリエチレンテレフタレートからなるものであるが、ポリエチレンテレフタレート以外に、酸成分としてテレフタル酸、ナフタレン−２，６−ジカルボン酸、イソフタル酸、ブチレンジカルボン酸、５−ナトリウムスルホイソフタル酸、アジピン酸等と、グリコール成分としてエチレングリコール、プロピレングリコール、ブタンジオール、シクロヘキサンジメタノール等との変性ポリエステル成分が全ポリエステルの１０モル％以下含まれたポリエステルであってもよい。
【００８２】
ＰＥＮとしては、ポリエチレン２，６ナフタレート、及びテレフタル酸と２−６ナフタレンジカルボン酸とエチレングリコールからなる共重合ポリエステル、およびこれらのポリエステルの二種以上の混合物を主要な構成成分とするポリエステルが好ましい。また、さらに他の共重合成分が共重合されていても良いし、他のポリエステルが混合されていても良い。
【００８３】
ＳＰＳは通常のポリスチレン（アタクチックポリスチレン）と異なり立体的に規則性を有したポリスチレンである。ＳＰＳの規則的な立体規則性構造部分をラセモ連鎖といい、２連鎖、３連鎖、５連鎖、あるいはそれ以上と規則的な部分がより多くあることが好ましく、本発明において、ラセモ連鎖は、２連鎖で８５％以上、３連鎖で７５％以上、５連鎖で５０％以上、それ以上の連鎖で３０％以上であることが好ましい。ＳＰＳの重合は特開平３−１３１８４３号明細書記載の方法に準じて行うことが出来る。
【００８４】
本発明に用いられる支持体の製膜方法及び下引製造方法は公知の方法を用いることができるが、好ましくは、特開平９−５００９４号の段落〔００３０〕〜〔００７０〕に記載された方法を用いることである。
【００８５】
次に、本発明に用いられるハロゲン化銀写真感光材料について説明する。
【００８６】
本発明に用いられるハロゲン化銀写真感光材料の乳剤層の膜厚は、Ｘ線画像情報の鮮鋭性を向上させ、癌等に対する十分な診断能を持たせるためには、０．５〜２．０μｍの膜厚であることが必要であるが、さらに診断能を向上させるためには、０．７〜１．５μｍがより好ましい。該乳剤層の膜厚とは、支持体の両側に乳剤層を有する場合は、片側一方の乳剤層の膜厚を言い、片側に乳剤層が多層ある場合は、それら全層を合計した膜厚を言う。
【００８７】
膜厚は、２３℃、５０％ＲＨの雰囲気に少なくとも２時間放置し、この感光材料の断面の電子顕微鏡写真を用いて算出することが出来る。また、上記の膜厚にするためにバインダー量で調節することが出来る。
【００８８】
本発明に用いられるハロゲン化銀写真感光材料に使用される乳剤は、公知の方法を用いて製造できる。結晶の晶癖は立方体、１４面体、８面体及び（１１１）面と、（１００）面等の面が任意に混在する、例えば、球状の形をしていてもよい。
【００８９】
ハロゲン化銀の結晶構造は、内部と外部が異なったハロゲン化銀組成からなっていてもよい。例えば、特開平２−８５８４６号等に開示されている内部高沃度型単分散粒子が挙げられる。
【００９０】
更にまた、本発明には平均アスペクト比が２以上の平板状粒子を用いることが好ましく、アスペクト比は３〜２０であることが更に好ましい。
【００９１】
本発明において、アスペクト比とは平板状粒子の主平面の直径（粒径）と厚みの比を言う。該平板粒子の主平面の直径とは、主平面の投影面積に等しい面積の円の直径を言う。本発明において平板状ハロゲン化銀粒子の主平面の直径は好ましくは０．０５〜２．０μｍ、更に好ましくは０．１〜１．５μｍ、特に好ましくは０．１５〜１．０μｍである。
【００９２】
一般に、平板状ハロゲン化銀粒子は、二つの平行な主平面を有する平板状であり、従って本発明における「厚み」とは平板状ハロゲン化銀粒子を構成する二つの平行な主平面の距離で表される。
【００９３】
本発明に用いられる平板状粒子の利点は、分光増感効率の向上、画像の粒状性及び鮮鋭性の改良などが得られるとして、例えば、英国特許第２，１１２，１５７号、米国特許第４，４３９，５２０号、同第４，４３３，０４８号、同第４，４１４，３１０号、同第４，４３４，２２６号、特開昭５８−１１３９２７号、同５８−１２７９２１号、同６３−１３８３４２号、同６３−２８４２７２号、同６３−３０５３４３号等で開示されており、乳剤はこれらの公報に記載の方法により調製することができる。
【００９４】
更に米国特許第４，０６３，９５１号、同第４，３８６，１５６号、同第５，２７５，９３０号、同第５，３１４，７９８号に記載されている（１００）主平面を有する平板状粒子も好ましく用いられる。
【００９５】
本発明に用いられる更に好ましいハロゲン化銀乳剤は、沃化銀３モル％未満の沃臭化銀、沃塩臭化銀、臭化銀、塩臭化銀、塩化銀であり、特に好ましくは沃化銀の含有率が１．０モル％未満の臭化銀、沃臭化銀または沃塩化銀である。上述した乳剤は、粒子表面に潜像を形成する表面潜像型或いは粒子内部に潜像を形成する内部潜像型、表面と内部潜像を形成する型の何れの乳剤であってもよい。
【００９６】
本発明に用いられるハロゲン化銀乳剤は単分散性であることが好ましく、更に平均体積粒径の変動係数が２０％以内の範囲、特に１０％以内の範囲に含まれるものが好ましく用いられる。本発明において、平均体積粒径とは、平板状粒子の場合は平板状粒子の体積を同体積を有する立方体の体積に換算して、個々の粒子の体積を換算した立方体の一辺の長さの平均を言う。その他の形状を有する粒子の場合も同じく換算する。尚、上記した立方体、１４面体の粒子と平板状粒子を混合して用いてもよい。
【００９７】
平均体積粒径の変動係数が１０％以内の範囲に含まれる単分散性乳剤を少なくとも１種用い、２種以上の乳剤を混合して使用する方法が好ましい。更には混合する複数の乳剤において最も高感度な乳剤に平板状乳剤を用い、最も低感度な乳剤に立方体乳剤を用いる方法である。
【００９８】
本発明に用いられるハロゲン化銀粒子には、前記熱現像感光材料のハロゲン化銀粒子と同様に、Ｆｅ、Ｃｏ、Ｒｕ、Ｒｈ、Ｒｅ、Ｏｓ、Ｉｒから選ばれる金属のイオン、金属錯体または金属錯体イオンを含有することが好ましく、１種類でも同種或いは異種の金属錯体を２種以上併用しても良い。ハロゲン化銀粒子中の含有率についても、同様であり、その好ましい具体例も前記熱現像感光材料のハロゲン化銀粒子に用いられる６配位金属錯体イオンと同様である。
【００９９】
乳剤は可溶性塩類を除去するためにヌードル水洗法、フロキュレーション沈降法、限外濾過法等の水洗方法がなされてよい。好ましい水洗法としては、例えば、特公昭３５−１６０８６号記載のスルホ基を含む芳香族炭化水素系アルデヒド樹脂を用いる方法、または特開昭６３−１５８６４４号記載の凝集高分子剤例示Ｇ３，Ｇ８などを用いる方法が特に好ましい脱塩法として挙げられる。
【０１００】
本発明における感光性ハロゲン化銀粒子は化学増感されていることが好ましく、増感方法としてはイオウ増感、セレン増感、テルル増感、貴金属増感、還元増感等公知の増感法を用いることができる。
【０１０１】
また、これら増感法は２種以上組み合わせて用いることもできる。イオウ増感にはチオ硫酸塩、チオ尿素化合物、無機イオウ等を用いることができる。セレン増感、テルル増感に好ましく用いられる化合物としては、特開平９−２３０５２７号記載の化合物を挙げることができる。貴金属増感法に好ましく用いられる化合物としては、例えば塩化金酸、カリウムクロロオーレート、カリウムオーリチオシアネート、硫化金、金セレナイド、或いは米国特許第２，４４８，０６０号、英国特許第６１８，０６１号等に記載の化合物を挙げることができる。
【０１０２】
還元増感法の具体的な化合物としてはアスコルビン酸、２酸化チオ尿素、塩化第１スズ、ヒドラジン誘導体、ボラン化合物、シラン化合物、ポリアミン化合物等を用いることができる。また、乳剤のｐＨを７以上またはｐＡｇを８．３以下に保持して熟成することにより還元増感することができる。
【０１０３】
本発明に用いられるハロゲン化銀写真感光材料には、分光増感色素としてシアニン色素、メロシアニン色素、コンプレックスシアニン色素、コンプレックスメロシアニン色素、ホロポーラーシアニン色素、スチリル色素、ヘミシアニン色素、オキソノール色素、ヘミオキソノール色素等を用いることができる。例えば特開昭６３−１５９８４１号、同６０−１４０３３５号、同６３−２３１４３７号、同６３−２５９６５１号、同６３−３０４２４２号、同６３−１５２４５号、米国特許第４，６３９，４１４号、同第４，７４０，４５５号、同第４，７４１，９６６号、同第４，７５１，１７５号、同第４，８３５，０９６号に記載された増感色素が使用できる。
【０１０４】
本発明に使用される有用な増感色素は例えばＲｅｓｅａｒｃｈ Ｄｉｓｃｌｏｓｕｒｅ Ｉｔｅｍ１７６４３IV−Ａ項（１９７８年１２月ｐ．２３）、同Ｉｔｅｍ１８４３１（１９７９年８月ｐ．４３７）に記載もしくは引用された文献に記載されている。
【０１０５】
特に各種レーザイメージャやスキャナの光源の分光特性に適した分光感度を有する増感色素を有利に選択することができる。例えば特開平９−３４０７８号、同９−５４４０９号、同９−８０６７９号記載の化合物が好ましく用いられる。有用なシアニン色素は、例えば、チアゾリン核、オキサゾリン核、ピロリン核、ピリジン核、オキサゾール核、チアゾール核、セレナゾール核及びイミダゾール核などの塩基性核を有するシアニン色素である。有用なメロシアニン染料で好ましいものは、上記の塩基性核に加えて、チオヒダントイン核、ローダニン核、オキサゾリジンジオン核、チアゾリンジオン核、バルビツール酸核、チアゾリノン核、マロノニトリル核及びピラゾロン核などの酸性核も含む。
【０１０６】
上記記載の増感色素は単独に用いてもよいが、それらの組合せを用いてもよく、増感色素の組合せは、特に強色増感の目的でしばしば用いられる。増感色素とともに、それ自身分光増感作用をもたない色素或いは可視光を実質的に吸収しない物質であって、強色増感を示す物質を乳剤中に含んでもよい。
【０１０７】
有用な増感色素、強色増感を示す色素の組合せ及び強色増感を示す物質はリサーチ・ディスクロージャ（Ｒｅｓｅａｒｃｈ Ｄｉｓｃｌｏｓｕｒｅ）１７６巻１７６４３（１９７８年１２月発行）第２３頁IVのＪ項、或いは特公平９−２５５００号、同４３−４９３３号、特開昭５９−１９０３２号、同５９−１９２２４２号等に記載されている。
【０１０８】
分光増感色素の添加は、メタノールのような有機溶媒に溶解した溶液として添加することができる。更に固体微粒子状の分散物を作製して添加することもできる。分光増感色素の添加量は、色素の種類や乳剤条件によって一様ではないが、ハロゲン化銀１モル当たり１〜９００ｍｇが好ましく、５〜４００ｍｇが特に好ましい。分光増感色素は、化学熟成工程の終了前に添加するのが好ましく、化学熟成の終了前に数回に分けて添加してもよい。更に好ましくはハロゲン化銀粒子の成長工程終了後から化学熟成工程の終了前であり、特に化学熟成開始前が好ましい。
【０１０９】
本発明において、化学増感（化学熟成）を停止させるには乳剤の安定性を考慮すると化学熟成停止剤を用いることが好ましい。この化学熟成停止剤としては、ハロゲン化物（例えば、臭化カリウム、塩化ナトリウム等）、カブリ防止剤または安定剤として知られている有機化合物（例えば、４−ヒドロキシ−６−メチル−１，３，３ａ，７−テトラザインデン）等が挙げられる。これらは単独もしくは複数の化合物を併用してもよい。
【０１１０】
本発明に用いられる感光材料の乳剤は、物理熟成または化学熟成前後の工程において、各種の写真用添加剤を用いることができる。
【０１１１】
本発明に用いられる支持体は、現像処理後に所定の光学濃度を得るため、及び現像処理後の画像の変形を防ぐためにプラスチックフイルム（例えば、ポリエチレンテレフタレート、ポリカーボネート、ポリイミド、ナイロン、セルローストリアセテート、ポリエチレンナフタレート）であることが好ましい。
【０１１２】
その中でも好ましい支持体としては、ポリエチレンテレフタレート（以下ＰＥＴと略す）、ポリエチレンナフタレート（以下ＰＥＮと略す）、及びシンジオタクチック構造を有するスチレン系重合体を含むプラスチック（以下ＳＰＳと略す）の支持体が挙げられる。支持体の厚みとしては５０〜３００μｍ程度が好ましく、更に好ましくは７０〜１８０μｍである。
【０１１３】
また熱処理したプラスチック支持体を用いることもできる。採用するプラスチックとしては、前記のプラスチックが挙げられる。支持体の熱処理とはこれらの支持体を製膜後、感光性層が塗布されるまでの間に、支持体のガラス転移点より３０℃以上高い温度で、好ましくは３５℃以上高い温度で、更に好ましくは４０℃以上高い温度で加熱することがよい。但し、支持体の融点を超えた温度で加熱しては本発明の効果は得られない。
【０１１４】
次に本発明に用いられるプラスチックについて説明する。
【０１１５】
ＰＥＴはポリエステルの成分が全てポリエチレンテレフタレートからなるものであるが、ポリエチレンテレフタレート以外に、酸成分としてテレフタル酸、ナフタレン−２，６−ジカルボン酸、イソフタル酸、ブチレンジカルボン酸、５−ナトリウムスルホイソフタル酸、アジピン酸等と、グリコール成分としてエチレングリコール、プロピレングリコール、ブタンジオール、シクロヘキサンジメタノール等との変性ポリエステル成分が全ポリエステルの１０モル％以下含まれたポリエステルであってもよい。
【０１１６】
ＰＥＮとしては、ポリエチレン２，６−ナフタレート、及びテレフタル酸と２，６−ナフタレンジカルボン酸とエチレングリコールからなる共重合ポリエステル、及びこれらのポリエステルの二種以上の混合物を主要な構成成分とするポリエステルが好ましい。また、更に他の共重合成分が共重合されていても良いし、他のポリエステルが混合されていても良い。
【０１１７】
ＳＰＳは通常のポリスチレン（アタクチックポリスチレン）と異なり立体的に規則性を有したポリスチレンである。ＳＰＳの規則的な立体規則性構造部分をラセモ連鎖といい、２連鎖、３連鎖、５連鎖、或いはそれ以上と規則的な部分がより多くあることが好ましく、本発明において、ラセモ連鎖は、２連鎖で８５％以上、３連鎖で７５％以上、５連鎖で５０％以上、それ以上の連鎖で３０％以上であることが好ましい。ＳＰＳの重合は特開平３−１３１８４３号明細書記載の方法に準じて行うことが出来る。
【０１１８】
本発明に用いられる支持体の製膜方法及び下引製造方法は公知の方法を用いることができるが、好ましくは、特開平９−５００９４号の段落〔００３０〕〜〔００７０〕に記載された方法を用いることである。
【０１１９】
本発明に用いられるハロゲン化銀写真感光材料は迅速処理に適するように、該感材の塗布工程において、予め適量の硬膜剤を添加しておき、現像−定着−水洗工程での水膨潤率を調整することで乾燥開始前の感光材料中の含水量を少なくしておくことが好ましい。尚、本発明の感光材料は現像処理中の膨潤率が５０〜１５０％が好ましく、膨潤後の膜厚が２０μｍ以下が好ましい。水膨潤率が１５０％を越えると乾燥不良を生じ、例えば自動現像機処理、特に迅速処理において搬送不良も併発する、また、水膨潤率が５０％未満では現像した際に現像ムラや残色が増加する悪い傾向がある。ここで言う水膨潤率とは、各処理液中で膨潤した後の膜厚と現像処理前の膜厚との差を求め、これを処理前の膜厚で除して１００倍したものを言う。
【０１２０】
本発明のハロゲン化銀写真感光材料はハロゲン化銀乳剤に更に目的に応じて種々の添加剤を添加することができる。使用される添加剤その他としては例えばＲＤ−１７６４３（１９７８年１２月）、同１８７１６（１９７９年１１月）及び同３０８１１９（１９８９年１２月）に記載されたものが挙げられる。それらの記載箇所を以下に掲載した。
【０１２１】

本発明に用いられるハロゲン化銀写真感光材料を現像処理する工程において、粉末処理剤や錠剤、丸薬、顆粒の如き固形処理剤などを使用しても良く、更に必要に応じ防湿加工を施したものを使用しても良い。
【０１２２】
本発明において用いられる粉末とは、微粒結晶の集合体のことをいう。本発明でいう顆粒とは、粉末に造粒工程を加えたもので、粒径５０〜５０００μｍの粒状物のことをいう。本発明でいう錠剤とは、粉末または顆粒を一定の形状に圧縮成型したもののことを言う。
【０１２３】
写真性能を安定に保つためには、自動現像機中の現像液の開口係数を小さくすることが有効である。特に開口係数が５０ｃｍ²／リットル以下が好ましい。すなわち、開口係数が５０ｃｍ²／リットルを超えると未溶解の固形処理剤や溶解した直後の濃厚な液が空気酸化を受け易くその結果、不溶物やスカムが発生し、自現機或いは処理される感材を汚染する等の問題を発生するが、開口係数が５０ｍ²／リットル以下でこれらの問題が解決される。本発明において、前記開口係数とは、処理液単位体積当たりの空気との接触面積で表され、単位は（ｃｍ²／リットル）である。
【０１２４】
本発明においては、自動現像機の開口係数は５０ｃｍ²／リットル以下が好ましく、更に好ましくは３０〜３ｃｍ²／リットルであり、特に好ましくは２０〜５ｃｍ²／リットルである。開口係数は一般に空気遮断する樹脂等を浮き蓋とすることで小さくしたり、また、特開昭６３−１３１１３８号、同６３−２１６０５０号、同６３−２３５９４０号に記載のスリット型現像装置によって小さくできる。
【０１２５】
本発明に用いられる固形処理剤は現像剤、定着剤、安定剤等写真用処理剤に用いられる。本発明に用いられる固形処理剤はある処理剤の１部の成分のみ固形化しても良いが、好ましくは該処理剤の全成分が固形化されていることである。各成分は別々の固形処理剤として成型され、同一個装されていることが望ましい。又別々の成分が定期的に包装でくり返し投入される順番に包装されていることも望ましい。
【０１２６】
本発明において固形処理剤を処理槽に供給する供給手段としては、例えば、固形処理剤が錠剤である場合、実開昭６３−１３７７８３号公報、同６３−９７５２２号公報、実開平１−８５７３２号公報等公知の方法があるが要は錠剤を処理槽に供給する機能が最低限付与されていればいかなる方法でも良い。
【０１２７】
また、固形処理剤が顆粒または粉末である場合には実開昭６２−８１９６４号、同６３−８４１５１号、特開平１−２９２３７５号記載の重力落下方式や実開昭６３−１０５１５９号、同６３−１９５３４５号等記載のスクリューまたはネジによる方式が公知の方法としてあるがこれらに限定されない。
【０１２８】
また、現像剤中には、現像主薬として特開平６−１３８５９１号（１９〜２０頁）記載のジヒドロキシベンゼン類、アミノフェノール類、ピラゾリドン類の他に特開平５−１６５１６１号記載のレダクトン類も好ましく用いられる。使用されるピラゾリドン類のうち特に４位が置換されたもの（ジメゾン、ジメゾンＳ等）は水溶性や固形処理剤自身の経時による変化が少なく特に好ましい。保恒剤として亜硫酸塩の他、有機還元剤を保恒剤として用いることができる。その他にキレート剤や硬膜剤の重亜硫酸塩付加物を添加することができる。また銀スラッジ防止剤として特開平５−２８９２５５号、特開平６−３０８６８０号（一般式［４−ａ］［４−ｂ］）記載の化合物を添加することも好ましい。
【０１２９】
シクロデキストリン化合物の添加も好ましく、特開平１−１２４８５３号記載の化合物が特に好ましい。現像剤にアミン化合物を添加することもでき、米国特許第４，２６９，９２９号記載の化合物が特に好ましい。
【０１３０】
現像剤には、緩衝剤を用いることが必要で、緩衝剤としては、炭酸ナトリウム、炭酸カリウム、重炭酸ナトリウム、重炭酸カリウム、リン酸三ナトリウム、リン酸三カリウム、リン酸二カリウム、ホウ酸ナトリウム、ホウ酸カリウム、四ホウ酸ナトリウム、四ホウ酸カリウム、ｏ−ヒドロキシ安息香酸ナトリウム、ｏ−ヒドロキシ安息香酸カリウム、５−スルホ−２−ヒドロキシ安息香酸ナトリウム（５−スルホサリチル酸ナトリウム）、５−スルホ−２−ヒドロキシ安息香酸カリウム等を挙げることができる。
【０１３１】
現像促進剤としては、特公昭３７−１６０８８号、同３７−５９８７号、同３８−７８２６号、同４４−１２３８０号、同４５−９０１９号及び米国特許第３，８１３，２４７号等に記載のチオエーテル系化合物、特開昭５２−４９８２９号及び同５０−１５５５４号等に記載のｐ−フェニレンジアミン系化合物、特開昭５０−１３７７２６号、特公昭４４−３００７４号、特開昭５６−１５６８２６号及び同５２−４３４２９号等に記載の４級アンモニウム塩類、米国特許第２，６１０，１２２号及び同第４，１１９，４６２号記載のｐ−アミノフェノール類、米国特許第２，４９４，９０３号、同第３，１２８，１８２号、同第４，２３０，７９６号、同第３，２５３，９１９号、特公昭４１−１１４３１号、米国特許第２，４８２，５４６号、同第２，５９６，９２６号及び同第３，５８２，３４６号等に記載のアミン系化合物、特公昭３７−１６０８８号、同４２−２５２０１号、米国特許第３，１２８，１８３号、特公昭４１−１１４３１号、同４２−２３８８３号及び米国特許第３，５３２，５０１号等に記載のポリアルキレンオキサイド、その他１−フェニル−３−ピラゾリドン類、ヒドラジン類、メソイオン型化合物、イミダゾール類等を必要に応じて添加することができる。
【０１３２】
カブリ防止剤としては、臭化カリウムの如きアルカリ金属ハロゲン化物及び有機カブリ防止剤が使用できる。有機カブリ防止剤としては、例えば、ベンゾトリアゾール、６−ニトロベンズイミダゾール、５−ニトロイソインダゾール、５−メチルベンゾトリアゾール、５−ニトロベンゾトリアゾール、５−クロロベンゾトリアゾール、２−チアゾリルベンズイミダゾール、２−チアゾリルメチルベンズイミダゾール、インダゾール、ヒドロキシアザインドリジン、アデニン、１−フェニル−５−メルカプトテトラゾール等を例として挙げることができる。更に、現像剤組成物には、必要に応じて、メチルセロソルブ、メタノール、アセトン、ジメチルホルムアミド、シクロデキストリン化合物、その他特公昭４７−３３３７８号、同４４−９５０９号各公報記載の化合物を現像主薬の溶解度を上げるための有機溶剤として使用することができる。更にまた、その他ステイン防止剤、スラッジ防止剤等各種添加剤を用いることができる。
【０１３３】
処理に先立ち、スタータを添加することも好ましく、スタータを固形化して添加することも好ましい、スタータとしてはポリカルボン酸化合物の如き有機酸の他にＫＢｒの如きアルカリ金属のハロゲン化物や有機抑制剤、現像促進剤が用いられる。
【０１３４】
スタータにより調整された現像液のｐＨは９〜１２の範囲が好ましく、更に好ましくは、９．５〜１０．５の範囲である。現像温度としては２０〜６０℃、好ましくは３０〜４５℃である。
【０１３５】
次に本発明に用いられる定着液について説明する。定着液としては、チオ硫酸塩を含有することが好ましい。チオ硫酸塩は、通常、リチウム、カリウム、ナトリウム、アンモニウム塩として用いられるが、好ましくはチオ硫酸ナトリウム、チオ硫酸アンモニウムである。アンモニウム塩を用いることにより定着速度の速い定着液が得られるが、保存性等の点からはナトリウム塩が好ましい。チオ硫酸塩の濃度は好ましくは０．１〜５モル／リットルであり、より好ましくは０．５〜２モル／リットル、更に好ましくは０．７〜１．８モル／リットルである。
【０１３６】
その他、定着剤として沃化物塩やチオシアン酸塩等も用いることができる。定着液は好ましくは亜硫酸塩を含有し、該亜硫酸塩の濃度は、チオ硫酸塩と亜硫酸塩の水系溶媒に対する溶解混合時において、０．２モル／リットル以下である。
【０１３７】
亜硫酸塩としては、固体のリチウム、カリウム、ナトリウム、アンモニウム塩等が用いられ、前記の固体チオ硫酸塩と共に溶解して用いられる。本発明に用いられる定着液は、水溶性クロム塩または水溶性アルミニウム塩等を含有してもよい。水溶性クロム塩としてはクロム明ばん等が挙げられ、水溶性アルミニウム塩としては、硫酸アルミニウム、塩化アルミニウムカリウム、塩化アルミニウム等を挙げることができる。これら、クロム塩またはアルミニウム塩の添加量は定着液１リットル当たり０．２〜３．０ｇで、好ましくは１．２〜２．５ｇである。また定着剤には、酢酸、クエン酸、酒石酸、リンゴ酸、琥珀酸、フェニル酢酸及びこれらの光学異性体等が含まれてもよい。これらの塩としては、例えば、クエン酸カリウム、クエン酸リチウム、クエン酸ナトリウム、クエン酸アンモニウム、酒石酸水素リチウム、酒石酸水素カリウム、酒石酸カリウム、酒石酸水素ナトリウム、酒石酸ナトリウム、酒石酸水素アンモニウム、酒石酸アンモニウムカリウム、酒石酸ナトリウムカリウム、リンゴ酸ナトリウム、リンゴ酸アンモニウム、琥珀酸ナトリウム、琥珀酸アンモニウム等に代表されるリチウム、カリウム、ナトリウム、アンモニウム塩等が好ましいものとして挙げられる。上記化合物の中でより好ましいものとしては、酢酸、クエン酸、リンゴ酸、フェニル酢酸及びこれらの塩である。化合物の添加量は０．２〜０．６モル／リットルが好ましい。酸としては、例えば、硫酸、塩酸、硝酸、ホウ酸のような無機酸及び塩や、蟻酸、プロピオン酸、シュウ酸、リンゴ酸等の有機酸類等が挙げられるが、好ましくは、ホウ酸、アミノポリカルボン酸類等の酸及び塩である。アミノカルボン酸で特に好ましいものはβ−アラニン、ピペリジン酸等がある。酸の好ましい添加量は０．５〜４０ｇ／リットルである。キレート剤としては、例えば、ニトリロ三酢酸、エチレンジアミン四酢酸等のアミノポリカルボン酸類及びこれらの塩等が挙げられる。界面活性剤としては、例えば、硫酸エステル化物、スルホン化物等のアニオン界面活性剤、ポリエチレングリコール系、エステル系等のノニオン界面活性剤、特開昭５７−６８４０号記載の両性界面活性剤等が挙げられる。湿潤剤としては、例えば、アルカノールアミン、アルキレングリコール等が挙げられる。定着促進剤としては、例えば、特開昭４５−３５７５４号、特公昭５８−１２２５３５号、同５８−１２２５３６号記載のチオ尿素誘導体、分子内に三重結合を有するアルコール、米国特許第４，１２６，４５９号記載のチオエーテル等が挙げられる。定着液の溶解或いは希釈後のｐＨは通常３．８以上が好ましく、更に好ましくは４．２〜５．５である。定着温度としては２０〜６０℃が好ましく、更に好ましくは３０〜４５℃である。
【０１３８】
現像時間は３〜９０秒が好ましく、更に好ましくは５〜６０秒であり、定着時間は３〜９０秒が好ましく、更に好ましくは５〜６０秒である。現像、定着、水洗、乾燥を含む全処理時間はＤｒｙ ｔｏ Ｄｒｙで１５〜２１０秒が好ましく、更に好ましくは１５〜９０秒である。
【０１３９】
【実施例】
以下、実施例を挙げて本発明を詳細に説明するが、本発明はこれらに限定されない。
【０１４０】
実施例１
《感光性ハロゲン化銀乳剤Ａの調製》
水９００ｍｌ中にイナートゼラチン７．５ｇ及び臭化カリウム１０ｍｇを溶解して温度３５℃、ｐＨを３．０に合わせた後、硝酸銀７４ｇを含む水溶液３７０ｍｌと（９８／２）のモル比の臭化カリウムと沃化カリウム（上記硝酸銀と等モル量）を含む水溶液３７０ｍｌ及びＫ₂〔Ｉｒ（ＮＯ）Ｃｌ₅〕を銀１モル当たり１×１０^-6モル及び塩化ロジウム塩を銀１モル当たり１×１０^-4モルを、ｐＡｇ７．７に保ちながらコントロールドダブルジェット法で添加した。その後４−ヒドロキシ−６−メチル−１，３，３ａ，７−テトラザインデンを添加しＮａＯＨでｐＨを５に調整して平均粒子サイズ０．０６μｍ、投影直径面積の変動係数８％、〔１００〕面比率８７％の立方体沃臭化銀粒子を得た。この乳剤にゼラチン凝集剤を用いて凝集沈降させ脱塩処理後フェノキシエタノール０．１ｇを加え、ｐＨ５．９、ｐＡｇ７．５に調整して、ハロゲン化銀乳剤を得た。次にこのハロゲン化銀乳剤に銀１モルあたり３×１０^ー2モルのハイポを加え、５５℃にて６０分間反応させて化学増感を施した。その後、ハロゲン化銀乳剤の温度を室温に降下させてから後記するカブリ防止剤等を加えることにより感光性ハロゲン化銀乳剤を調製した。
【０１４１】
特開平９−１２７６４３号記載の実施例１の方法に従い、下記のような方法でベヘン酸銀を作製した。
【０１４２】
《ベヘン酸ナトリウム塩溶液の調製》
３４０ｍｌのイソプロパノールにベヘン酸３４ｇを６５℃で溶解した。次に攪拌しながら０．２５Ｎの水酸化ナトリウム水溶液をｐＨ８．７になる様に添加した。この際水酸化ナトリウム水溶液は約４００ｍｌ必要とした。次にこのベヘン酸ナトリウム水溶液を減圧濃縮を行いベヘン酸ナトリウムの濃度が重量％で８．９％とした。
【０１４３】
《ベヘン酸銀の調製》
７５０ｍｌの蒸留水中に３０ｇのオセインゼラチンを溶解した溶液に２．９４Ｍの硝酸銀溶液を加え銀電位を４００ｍＶとした。この中にコントロールドダブルジェット法を用いて７８℃の温度下で前記ベヘン酸ナトリウム塩溶液３７４ｍｌを添加し同時に２．９４Ｍの硝酸銀水溶液を添加した。添加時のベヘン酸ナトリウム及び硝酸銀使用量はそれぞれ０．０９２モル、０．１０１モルであった。
【０１４４】
添加終了後さらに３０分攪拌し限外濾過により水溶性塩類を除去した。
【０１４５】
《感光性乳剤の調製》
このベヘン酸銀分散物に前記ハロゲン化銀乳剤を０．０１モル加え、更に攪拌しながらポリ酢酸ビニルの酢酸ｎ−ブチル溶液（１．２ｗｔ％）１００ｇを徐々に添加して分散物のフロックを形成後、水を取り除き、更に２回の水洗と水の除去を行った後、バインダーとしてポリビニルブチラール（平均分子量３０００）の２．５ｗｔ％の酢酸ブチルとイソプロピルアルコールの１：２混合溶液６０ｇを攪拌しながら加えた後、こうして得られたゲル状のベヘン酸及びハロゲン化銀の混合物にバインダーとしてポリビニルブチラール（平均分子量４０００）及びイソプロピルアルコールを加え分散した。
【０１４６】
ＰＥＴ支持体上に以下の各層を順次形成し、試料を作製した。尚、乾燥は各々７５℃、５分間で行った。
【０１４７】
バック面側塗布：以下の組成の液を湿潤厚さ８０μｍになるように塗布した。
【０１４８】
ポリビニルブチラール（１０％イソプロパノール溶液） １５０ｍｌ
染料−Ｂ ７０ｍｇ
染料−Ｃ ７０ｍｇ
【０１４９】
【化４】

【０１５０】
感光層面側塗布
感光層１：以下の組成液を塗布銀量が２．０ｇ／ｍ²、バインダーとしてのポリビニルブチラールを表１に記載されている量（ｇ／ｍ²）になる様に塗布した。
【０１５１】
感光性ハロゲン化銀乳剤Ａ 銀量として０．１ｇ／ｍ²になる量
ベヘン酸銀 銀量として１．９ｇ／ｍ²になる量
増感色素−１（０．１％ＤＭＦ溶液） ２ｍｇ
カブリ防止剤−１（０．０１％メタノール溶液） ３ｍｌ
カブリ防止剤−２（１．５％メタノール溶液） ８ｍｌ
カブリ防止剤−３（２．４％ＤＭＦ溶液） ５ｍｌ
フタラゾン（４．５％ＤＭＦ溶液） ８ｍｌ
硬調化剤Ｈ（１％メタノール／ＤＭＦ＝４：１溶液） ２ｍｌ
還元剤Ａ−４（２０％メタノール溶液） ２９．５ｍｌ
【０１５２】
【化５】

【０１５３】
【化６】

【０１５４】
表面保護層：以下の組成の液を湿潤厚さ５０μｍになる様に各感光層上に塗布した。
【０１５５】
アセトン １７５ｍｌ
２−プロパノール ４０ｍｌ
メタノール １５ｍｌ
セルロースアセテート ８．０ｇ
フタラジン １．０ｇ
４−メチルフタル酸 ０．７２ｇ
テトラクロロフタル酸 ０．２２ｇ
テトラクロロフタル酸無水物 ０．５ｇ
平均粒子サイズ４μｍの単分散シリカ バインダーに対して１％（Ｗ／Ｗ）
《露光及び現像処理》
前述のＦＰＤで得たＸ線画像情報（初期の肺ガンの腫瘤状疑似陰影を含んだ胸部ファントム像）をレーザスキャナで露光し、その後ヒートドラムを有する自動現像機を用いて、１１０℃で１５秒熱現像処理した。その際、露光及び現像は２３℃、５０％ＲＨに調湿した部屋で行った。
【０１５６】
同じファントム、胸部Ｘ線画像をコニカ（株）製レジウス３３０でＸ線画像を入力し、同様に露光し、腫瘤状疑似陰影の検出能を５段階評価した。
【０１５７】
なお、上記記載の評価は、同一の観察条件下で行い、８名の評価の平均値で表した。
【０１５８】
《鮮鋭性の評価》
５ 明らかに、違いが分かる非常に優れたレベル
４ 有意さが認められるやや優れたレベル
３ 市場において特に問題がないレベル
２ 若干劣化が認められるが、大きな問題が無いレベル
１ 著しい劣化が認められ、大きな問題があるレベル
《乾燥膜厚の測定方法》
２３℃、５０％ＲＨの雰囲気に少なくとも２時間放置した試料の断面を電子顕微鏡を用いて撮影し、感光性層の乾燥膜厚を測定した。
【０１５９】
得られた結果を下記の表１に示す。
【０１６０】
【表１】

【０１６１】
表１の結果から、本発明の画像記録方法を用いた試料２〜５は、感光性層の膜厚を薄くすることにより顕著に鮮鋭性が向上していることがわかる。それに比べて、レジウス３３０を使用する従来の画像記録方法を用いた試料では、感光性層の膜厚を薄くしても、鮮鋭性が向上していないことが明らかである。
【０１６２】
実施例２
《感光材料の調製》
下記のように、ハロゲン化銀乳剤Ｅ１及びハロゲン化銀乳剤Ｅ２を調製した。
【０１６３】
Ａ１
オセインゼラチン ２４．２ｇ
水 ９６５７ｍｌ
Ｓ−３（１０％メタノール水溶液） ６．７８ｍｌ
ＨＯ−（ＣＨ₂ＣＨ₂Ｏ）_n−（ＣＨ（ＣＨ₃）ＣＨ₂Ｏ）₁₇−（ＣＨ₂ＣＨ₂Ｏ）_mＨ
ｎ＋ｍ≒５．７
臭化カリウム １０．８ｇ
１０％ 硝酸 １１４ｍｌ
Ｂ１
２．５Ｎ 硝酸銀水溶液 ２８２５ｍｌ
Ｃ１
臭化カリウム ８４１ｇ
水で２８２５ｍｌに仕上げる。
【０１６４】
Ｄ１
１．７５Ｎ 臭化カリウム水溶液 下記銀電位制御量
４０℃で特公昭５８−５８２８８号、同５８−５８２８９号に示される混合攪拌機を用いて溶液Ａ１に溶液Ｂ１及び溶液Ｃ１の各々４６４．３ｍｌを同時混合法により９０秒間で添加し、核形成を行った。
【０１６５】
溶液Ｂ１及び溶液Ｃ１の添加を停止した後、６０分間で核を含む溶液Ａ１の温度を６０℃に上昇させ、３％ＫＯＨでｐＨを５．０に合わせた後、再び溶液Ｂ１と溶液Ｃ１を同時混合法により、各々５５．４ｍｌ／ｍｉｎの流量で４２分間添加した。この４２℃から６０℃への昇温及び溶液Ｂ１、Ｃ１による再同時混合の間の銀電位（飽和銀−塩化銀電極を比較電極として銀イオン選択電極で測定）を溶液Ｄ１を用いて、各々、＋１４ｍＶ及び＋２５ｍＶになるように制御した。
【０１６６】
添加終了後、３％ＫＯＨによってｐＨを６に合わせ、直ちに脱塩、水洗を行い、乳剤Ｅ１を得た。この臭化銀乳剤は、ハロゲン化銀粒子の全投影面積の９０％以上が最大隣接辺比が１．０〜２．０の六角平板粒子からなり、六角平板粒子の平均厚さは、０．０８μｍ、平均直径（円換算直径）は０．４５μｍであることを電子顕微鏡にて確認した。
【０１６７】
また、厚さの変動係数は２２％、双晶面間距離の変動係数は３３％であった。尚、この臭化銀乳剤の平均体積粒径は０．２３μｍであった。平均体積粒径の変動係数は１５％であった。
【０１６８】
次に、上記の乳剤を６０℃にした後に、分光増感色素Ｄ−１の所定量を添加した１０分後にアデニン、チオシアン酸アンモニウム、塩化金酸及びチオ硫酸ナトリウムの混合水溶液及びトリフェニルフォスフィンセレナイドの分散物液を加え、総計９０分間の熟成を施した。熟成終了時に安定剤として４−ヒドロキシ−６−メチル−１，３，３ａ，７−テトラザインデンの所定量を添加した。
【０１６９】
尚、上記の添加剤とその添加量（ＡｇＸ１モル当たり）を下記に示す。
【０１７０】

６０℃、ｐＡｇ：８．０，ｐＨ：２．０に制御しつつ、臭化カリウム水溶液と硝酸銀水溶液をダブルジェット法で０．５％ゼラチン水溶液中に添加し平均粒径０．１μｍの単分散立方体乳剤を得た。この臭化銀をコアとして、銀１モル当たり１×１０^-6モルの６塩化イリジウム酸カリウムを含む臭化カリウム水溶液と硝酸銀水溶液をｐＡｇ＝７．３になるようにコントロールしながら添加し平均体積粒径０．２２μｍの単分散立方体乳剤（１，０００個の粒子を測定した結果、（１００）面を９８％有し、粒径の変動係数１０％）を得た。
【０１７１】
この乳剤を４０℃に保ちながら、ナフタレンスルホン酸ナトリウムのホルムアルデヒド縮合物と硫酸マグネシウムを加え、攪拌、静置後、過剰塩をデカンテーションにより除去した。次に適当量のゼラチン水溶液に再分散し、乳剤Ｅ２を得た。
【０１７２】
次に、上記の乳剤を６０℃にした後に、分光増感色素Ｄ−１の所定量を添加した１０分後にアデニン、チオシアン酸アンモニウム、塩化金酸及びチオ硫酸ナトリウムの混合水溶液及びトリフェニルホスフィンセレナイドの分散物を加え、総計７０分間の熟成を施した。熟成終了時に安定剤として４−ヒドロキシ−６−メチル−１，３，３ａ，７−テトラザインデンの所定量を添加した。
【０１７３】
尚、上記の添加剤とその添加量（ＡｇＸ１モル当たり）を下記に示す。
【０１７４】

得られた乳剤Ｅ１、Ｅ２をＥ１：Ｅ２＝１０：９０の割合で混合した乳剤Ｅ３を使用し、下記の試料を作製した。
【０１７５】
《乳剤層塗布液の調製》
上記で得た乳剤Ｅ３に下記の各種添加剤を加えた。
【０１７６】

ゼラチン量は表２の記載量になるように調製した。
【０１７７】
《保護層塗布液の調製》
ゼラチン 表２に記載量

得られたハロゲン化銀写真感光材料を以下に示す現像液、定着液を用いて処理を行い評価した。
【０１７８】
《現像液》

【０１７９】
【化７】

【０１８０】
水を加えて１リットルとし、水酸化カリウムでｐＨ１０．０に調整する。
【０１８１】
定着液の組成を下記に示す。
【０１８２】
《定着液》
チオ硫酸アンモニウム １３０．０ｇ
チオ硫酸ナトリウム １５．０ｇ
亜硫酸ナトリウム １０．０ｇ
酢酸ナトリウム ３０．０ｇ
琥珀酸 １０．５ｇ
酒石酸 ２．５ｇ
硫酸アルミニウム（８水塩） １５．０ｇ
Ｄ−マンニット １５．０ｇ
Ｄ−ソルビット ９．０ｇ
水を加えて１リットルとし、水酸化ナトリウムでｐＨ４．６０に調整する。
【０１８３】
現像液、定着液の補充量は、現像液が現像主薬の補充量に換算して５０ミリモル／ｍ²、定着液が定着剤の補充量に換算して１５０ミリモル／ｍ²と設定した。
【０１８４】
表２に記載の試料に対し、各々、前述のＦＰＤで得たＸ線画像情報（初期の肺ガンの腫瘤状疑似陰影を含んだ胸部ファントム像）をレーザスキャナで露光し、前述の処理液をいれたコニカ（株）製自動現像機ＴＣＸ−７０１を用いて、現像温度３５度、定着温度３４℃で４５秒処理を行った。
【０１８５】
同じ患者さんの同じ部位の、胸部Ｘ線画像（被爆線量をそろえる）をコニカ（株）製レジウス３３０（輝尽性蛍光体プレートを用いた従来のＸ線画像形成システム）でＸ線画像を入力し、試料Ｎｏ．１〜５のフィルムに同様に露光し、スリガラス状陰影の検出能を５段階評価した。ランク５は最もよく検出できるレベルを示し、ランク１は全くわからないレベルを示す。
【０１８６】
なお、上記記載の評価は、同一観察条件下で行い、８名の評価の平均値で表した。
【０１８７】
【表２】

【０１８８】
表２の結果から、本発明の画像記録方法を用いた試料２〜５は、感光性層の膜厚を薄くすることにより顕著に鮮鋭性が向上していることがわかる。それに比べて、レジウス３３０を使用する従来の画像記録方法を用いた試料では、感光性層の膜厚を薄くしても、鮮鋭性が向上していないことが明らかである。
【０１８９】
【発明の効果】
本発明により、ＦＰＤを用いるＸ線画像記録方法において、感光性のハロゲン化銀、非感光性の還元性銀源および該銀源の還元剤を含有する熱現像感光材料の感光性層の膜厚を１μｍ〜１０μｍに薄膜化することにより鮮鋭性に優れた画像を与えるＸ線画像記録方法を提供することができた。また、ＦＰＤを用いるＸ線画像記録方法において、ハロゲン化銀写真感光材料の乳剤層の膜厚を０．５μｍ〜２．０μｍに薄膜化することにより鮮鋭性に優れた画像を与えるＸ線画像記録方法を提供することができた。
【図面の簡単な説明】
【図１】Ｘ線画像形成システムの概略構成図である。
【図２】ＦＰＤを示す概略断面図である。
【図３】ＦＰＤを示す概略平面図である。
【符号の説明】
１ Ｘ線管
２ ＦＰＤ
３ 画像処理部
４ ネットワーク
５ ＣＲＴディスプレイ
６ レーザイメージャ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an X-ray image recording method.
[0002]
[Prior art]
Conventionally, in the fields of printing plate making and medical treatment, waste liquids resulting from wet processing of image forming materials have been a problem in terms of workability. In recent years, reduction of processing waste liquids has been strongly desired from the viewpoint of environmental conservation and space saving. Yes. In the medical field, pathological conditions have also changed due to changes in lifestyle habits, aging, and environmental changes, and the number of cancer patients is particularly increasing. In particular, early detection is important for the treatment of cancer diseases, and an improvement in the detection rate in health examinations is required. Along with the development and spread of various diagnostic methods such as CT and MR, the importance of complex image diagnosis is increasing, and a system with higher diagnostic ability is demanded even in direct X-ray imaging.
[0003]
Conventionally, an X-ray image is captured by an imaging plate using a photostimulable phosphor, an image signal is extracted by scanning exposure of the laser beam to the plate, the signal is converted into a digital signal, and then converted into a laser beam intensity. A system for exposing a line image to a silver halide photographic material is known.
[0004]
Compared with the conventional screen / film system, the above-mentioned system can confirm the image signal by using a CRT monitor or the like, and can adjust the amount of light when the silver halide photographic material is exposed. There are advantages in that it is possible to reduce re-shooting due to excess or deficiency, and to change the tone of the finish by changing data such as edge enhancement of the image.
[0005]
However, even in the system using the photostimulable phosphor, for example, the ability to discriminate early microscopic lesions such as cancer is not sufficient, and a system with even better sharpness is required for improving the diagnostic ability. .
[0006]
In addition, from the viewpoint of environmental conservation, space saving, and reduction of processing waste liquid, it is necessary to have a technology related to photothermographic materials for photographic technology that can be efficiently exposed with a laser imager and can form a clear black image with high resolution. It is said that. As this technique, for example, a photothermographic material containing an organic silver salt, photosensitive silver halide grains and a reducing agent on a support as described in US Pat. No. 3,152,904 is known. ing.
[0007]
However, even when the photostimulable phosphor and the photothermographic material described above are combined, the ability to diagnose early cancer or the like is not sufficient, and further improvement in diagnostic ability due to increased sharpness has been demanded. .
[0008]
In general, reducing the film thickness of a silver halide photographic light-sensitive material or a photothermographic material is an effective means for improving the sharpness of an image to be obtained. However, when the photostimulable phosphor described above is used, a sufficient sharpness improving effect cannot be obtained even if the film thickness of the silver halide photographic light-sensitive material or photothermographic material is reduced.
[0009]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION A first object of the present invention is a photothermographic material containing a photosensitive silver halide, a non-photosensitive reducible silver source, and a reducing agent for the silver source in an X-ray image recording method using a flat panel detector. It is to provide an X-ray image recording method which gives an image having excellent sharpness by reducing the film thickness of the photosensitive layer to 1 μm to 10 μm, and a second object of the present invention is to provide a flat panel In an X-ray image recording method using a detector, an X-ray image recording method for providing an image having excellent sharpness by reducing the film thickness of an emulsion layer of a silver halide photographic light-sensitive material to 0.5 μm to 2.0 μm. Is to provide.
[0010]
[Means for Solving the Problems]
The above object of the present invention has been achieved by the following items 1-2.
[0011]
1. X-ray image information is captured by a flat panel detector, X-ray image information is taken out from the flat panel detector as an image signal, converted into laser light intensity, photosensitive silver halide, non-photosensitive reducible silver source and In an X-ray image recording method for obtaining an X-ray image by performing a scanning exposure on a photothermographic material containing a reducing agent for the silver source and then performing a heat treatment, the dry film thickness of the photosensitive layer of the photothermographic material Is 1 μm to 10 μm.
[0012]
2. X-ray image information is captured by the FPD, X-ray image information is taken out from the FPD as an image signal, converted into laser light intensity, scanned and exposed to a silver halide photographic material, and an X-ray image is obtained by development processing. In the X-ray image recording method, the film thickness of the emulsion layer of the silver halide photographic light-sensitive material is 0.5 μm to 2.0 μm.
[0013]
The present invention will be described in detail below.
[0014]
Embodiments of an X-ray image forming method and an X-ray image forming system using the flat panel detector of the present invention will be described based on the drawings, but the present invention is not limited to these.
[0015]
1 is a schematic configuration diagram of an X-ray image forming system, FIG. 2 is a schematic sectional view showing a flat panel detector (hereinafter abbreviated as FPD), and FIG. 3 is a schematic plan view showing the FPD.
[0016]
As shown in FIG. 1, the X-ray image forming system captures an object 60 with X-rays emitted from the X-ray tube 1 and captures X-ray image information in the FPD 2. X-ray image information is taken out from the FPD 2 as an image signal, subjected to image processing by the image processing unit 3 and sent to the network 4. A CRT display 5 and a laser imager 6 are connected to the network 4. An X-ray image is displayed on the CRT display 5, and an X-ray image is printed by the laser imager 6 and output.
[0017]
The FPD 2 is configured as shown in FIGS.
[0018]
As shown in FIG. 2, the FPD 2 is configured by sequentially laminating a photoconductive layer 21, a dielectric layer 22, and a front conductive layer 23 on a dielectric substrate layer 20. A plurality of first micro conductive electrode micro plates 24 are provided on a dielectric substrate layer 20 such as a glass plate. A capacitive dielectric material 25 is formed on the plurality of first minute conductive electrode microplates 24. Even if the dielectric layer 22 is removed from the FPD 2, an X-ray image can be formed, and the present invention can be realized. In this case, however, the charge amount stored in the charge storage capacitor 36 can be retained and the sharpness of the X-ray image can be achieved. May decrease somewhat.
[0019]
Further, a plurality of transistors 29 having two electrodes 26 and 27 and a gate 28 are stacked on the dielectric substrate layer 20. Further, a plurality of second micro conductive electrode micro plates 30 are stacked on the dielectric substrate layer 20.
[0020]
As shown in FIG. 3, at least one transistor 29 connects a plurality of second micro conductive electrode microplates 30 to an X address line 41 and a Y sense line 42. The charge storage capacitor 36 is formed by the first micro conductive electrode micro plate 24, the second micro conductive electrode micro plate 30, and the capacitive dielectric material 25. The second micro conductive electrode microplate 30 is also connected to the electrode 27 of the transistor 29. The first minute conductive electrode microplate 24 is connected to the ground.
[0021]
Transistor 29 acts as a bi-directional switch, allowing current to flow between Y sense line 42 and charge storage capacitor 36 depending on whether a bias voltage is applied to the gate via X address line 41.
[0022]
Conductive electrodes or X address lines 41 and conductive electrodes or Y sense lines 42 are arranged in a space between the plurality of second micro conductive electrodes microplate 30. The X address line 41 and the Y sense line 42 are arranged so as to be substantially orthogonal to each other as shown in the figure. The X address line 41 and the Y sense line 42 can be individually accessed along the side or edge of the FPD 2 through lead wires or connectors.
[0023]
Each of the X address lines 41 is sequentially addressed by applying a bias voltage according to the line to the gate of the transistor 29 connected to the addressed X address line 41. As a result, the transistor 29 becomes conductive, and the charge stored in the corresponding charge storage capacitor 36 flows to the Y sense line 42 and to the input side of the charge detector 46. The charge detector 46 generates a voltage output that is proportional to the charge detected on the Y sense line 42. The output of the charge detector 46 is sampled sequentially to obtain an image signal representing the charge distribution of the microcapacitor on the addressed X address line 41, each microcapacitor representing one image pixel. When a signal is read out from a certain pixel line on the X address line 41, the charge amplifier is reset through the reset line 49. The next X address line 41 is addressed and this process is repeated until all charge storage capacitors 36 have been sampled and the entire image has been read.
[0024]
As described above, the X-ray image information is taken out from the FPD as an image signal, converted into laser light intensity, and recorded on the photothermographic material or silver halide photographic material used in the present invention. By performing the processing, it is possible to quickly and surely obtain a high-quality X-ray image that exhibits high sharpness required for, for example, mammography and limb bones, and that exhibits high diagnostic ability.
[0025]
The photothermographic material used in the present invention will be described in detail.
[0026]
The photothermographic material used in the present invention forms a photographic image using a photothermographic processing method containing a photosensitive silver halide, a non-photosensitive reducible silver source, and a reducing agent for the silver source. Is.
[0027]
The film thickness of the photosensitive layer of the photothermographic material used in the present invention is 1 to 10 μm in order to improve the sharpness of the X-ray image information and to have sufficient diagnostic ability for early cancer or the like. However, in order to further improve the diagnostic ability, a film thickness of 2 to 5 μm is preferable. One means for adjusting the film thickness of the photosensitive layer is to adjust the binder amount. For example, the binder amount of the photosensitive layer of the photothermographic material used in the present invention is 0.1 to 5 g / m.²Is preferred.
[0028]
Binder suitable for the photothermographic material used in the present invention is transparent or translucent and generally colorless, and is a natural polymer synthetic resin, polymer and copolymer, and other media for forming a film such as gelatin, gum arabic, and polyvinyl alcohol. , Hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, polyvinyl pyrrolidone, casein, starch, polyacrylic acid, polymethyl methacrylic acid, polyvinyl chloride, polymethacrylic acid, styrene-maleic anhydride copolymer, styrene-acrylonitrile copolymer Polymers, styrene-butadiene copolymers, polyvinyl acetals (for example, polyvinyl formal and polyvinyl butyral, polyesters, polyurethanes, phenoxy resins, polyvinylidene chloride, polymers Epoxides, polycarbonates, polyvinyl acetate, cellulose esters, and polyamides. May be non-hydrophilic or hydrophobic.
[0029]
Details of the photothermographic material that can be used in the present invention are described in, for example, U.S. Pat. Nos. 3,152,904, 3,457,075, and D.I. “Dry Silver Photographic Material” by Morgan, D.M. Morgan and B.M. “Thermally Processed Silver Systems” by Shely (Imaging Processes and Materials), 8th edition, Sturge V. (Walworth), A. Shepp (2nd page, 1969), and the like.
[0030]
The photosensitive silver halide grains used in the present invention will be described. In the present invention, in order to keep the white turbidity after image formation low and to obtain a good image quality, it is preferable that the average particle size is small, the average particle size is 0.2 μm or less, more preferably 0.01 μm to 0.00. 17 micrometers, especially 0.02 micrometer-0.14 micrometer are preferable. The grain size referred to here means the length of the edge of the silver halide grain when the photosensitive silver halide grain is a so-called normal crystal of a cube or octahedron. Further, when the silver halide grain is a tabular grain, it means a diameter when converted into a circular image having the same area as the projected area of the main surface. The silver halide is preferably monodispersed. The monodispersion here means that the monodispersity obtained by the following formula is 40 or less. The particle size is more preferably 30 or less, and particularly preferably 0.1 to 20 particles.
[0031]
Monodispersity = (standard deviation of particle size) / (average value of particle size) × 100
Examples of the shape of the photosensitive silver halide grains used in the present invention include cubes, octahedrons, tabular grains, spherical grains, rod-shaped grains, potato-shaped grains and the like. Tabular grains are preferred. When tabular silver halide grains are used, the average aspect ratio is preferably 2 or more and 100 or less, more preferably 3 or more and 50 or less. These are described in US Pat. Nos. 5,264,337, 5,314,798, 5,320,958, etc., and the desired tabular grains can be easily obtained. Further, grains having rounded corners of silver halide grains can be preferably used. The outer surface of the silver halide grain is not particularly limited, but the ratio occupied by the Miller index [100] plane is preferably high, and this ratio is 50% or more, further 70% or more, particularly 80% or more. preferable. The ratio of the Miller index [100] plane is determined by T.T. based on the adsorption dependency of the [111] plane and the [100] plane in the adsorption of the sensitizing dye. Tani, J .; ImagingSci. 29, 165 (1985).
[0032]
The halogen composition is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide, and silver iodide. In the present invention, silver bromide or silver iodobromide can be preferably used. Particularly preferred is silver iodobromide, and the silver iodide content is preferably from 0.1 mol% to 40 mol%, more preferably from 0.1 mol% to 20 mol%. The distribution of the halogen composition in the grain may be uniform, the halogen composition may be changed stepwise, or may be continuously changed. High silver iodobromide grains can be used. Further, silver halide grains preferably having a core / shell structure can be used.
[0033]
The photographic emulsion used in the present invention is P.I. Chifie et Physique Photographic (published by Paul Montel, 1967) by Glafkides. F. Duffin's Photographic Emission Chemistry (published by The Focal Press, 1966), V.C. L. It can be prepared using the method described in Making and Coating Photographic Emulsion (published by The Focal Press, 1964) by Zelikman et al. That is, any of an acidic method, a neutral method, an ammonia method, etc. may be used, and the formation of reacting a soluble silver salt and a soluble halogen salt may be any one of a one-side mixing method, a simultaneous mixing method, and a combination thereof. Good. The silver halide may be added to the image forming layer by any method, and at this time, the silver halide is disposed in the vicinity of the reducible silver source. Further, the silver halide may be prepared by converting a part or all of silver in the organic acid silver to silver halide by the reaction of the organic acid silver and the halogen ion, or the silver halide is prepared in advance. This may be added to the solution for preparing the organic silver salt, or a combination of these methods is possible, but the latter is preferred. In general, the silver halide is preferably contained in an amount of 0.75 to 30% by weight based on the organic silver salt.
[0034]
The silver halide grains used in the present invention preferably contain a metal ion selected from Fe, Co, Ru, Rh, Re, Os and Ir, and at least one kind of the same or different kind of metal ions can be used. You may use together. The preferred content is 1 x 10 per mole of silver.^-9From mole to 1 × 10^-2The molar range is preferred, 1 × 10^-8From mole to 1 × 10^-FourThe range of is more preferable. In the present invention, the metal ions described above can be introduced into silver halide in the form of metal complexes or metal complex ions. As these metal complexes or complex metal ions, hexacoordinate metal complexes represented by the following general formula are preferably used.
[0035]
General formula [ML₆]^m
In the formula, M represents a transition metal selected from Group 6 to 10 elements of the periodic table, L represents a ligand, and m represents 0,-, 2-, 3-, or 4-. Specific examples of the ligand represented by L include halides (fluoride, chloride, bromide and iodide), cyanide, cyanate, thiocyanate, selenocyanate, tellurocyanate, azide and aco. A ligand, nitrosyl, thionitrosyl and the like can be mentioned, and ako, nitrosyl, thionitrosyl and the like are preferable. When an acoligand is present, it preferably occupies one or two of the ligands. L may be the same or different.
[0036]
Specific preferred examples of M are rhodium (Rh), ruthenium (Ru), rhenium (Re), osmium (Os), and iridium (Ir).
[0037]
Specific examples of transition metal complex ions are shown below, but the present invention is not limited thereto.
[0038]
1: [RhCl₆]^3-
2: [RhCl_Five(H₂O)]^2-
3: [Rh (NO)₂Cl_Four]^-
4: [Rh (NO) (H₂O) Cl_Four]^-
5: [Rh (NS) Cl_Five]^2-
6: [RuCl₆]^3-
7: [RuBr₆]^3-
8: [Ru (NO) Cl_Five]^2-
9: [Ru (NO) (H₂O) Cl_Four]^-
10: [Ru (NS) Cl_Five]^2-
11: [RuBr_Four(H₂O)]^2-
12: [Ru (NO) (CN)_Five]^2-
13: [ReCl₆]^3-
14: [Re (NO) Cl_Five]^2-
15: [Re (NO) (CN)_Five]^2-
16: [Re (NO) Cl (CN)_Four]^2-
17: [Re (NO) Cl_Five]^-
18: [Re (NS) Cl_Four(SeCN)]^2-
19: [OsCl₆]^3-
20: [Os (NO) Cl_Five]^2-
21: [Os (NS) Cl_Four(TeCN)]^2-
22: [Os (NS) Cl (SCN)_Four]^2-
23: [IrCl_Five]^2-
24: [Ir (NO) Cl_Five]^2-
25: [Cr (NO) Cl_Five]^2-
26: [CrCl₆]^Four-
For chromium, cobalt, and iron compounds, 6-cyano metal complex ions can be preferably used. Specific examples are shown below.
[0039]
27: [Fe (CN)₆]^Four-
28: [Fe (CN)₆]^3-
29: [Co (CN)₆]^3-
30: [Cr (CN)₆]^Four-
31: [Cr (CN)₆]^3-
The compounds providing these metal ions or complex ions are preferably added during silver halide grain formation and incorporated into the silver halide grains. Preparation of silver halide grains, that is, nucleation, growth, physical ripening , May be added at any stage before or after chemical sensitization, but is preferably added at the stage of nucleation, growth and physical ripening, more preferably at the stage of nucleation and growth, most preferably Preferably, it is added at the stage of nucleation. In addition, it may be divided and added several times, or it can be uniformly contained in the silver halide grains. JP-A-63-29603, JP-A-2-306236, 3 As described in JP-A Nos. 167545, 4-76534, 6-110146, 5-273683, etc., the particles can be contained with a distribution. Preferably, a distribution can be provided inside the particles. These metal compounds can be added by dissolving in water or an appropriate organic solvent (for example, alcohols, ethers, glycols, ketones, esters, amides). A method in which an aqueous solution or an aqueous solution in which a metal compound and NaCl, KCl are dissolved together is added to the water-soluble silver salt solution or water-soluble halide solution during particle formation, or the silver salt solution and the halide solution are mixed simultaneously. When adding a third aqueous solution, a method of preparing silver halide grains by a method of simultaneous mixing of three liquids, a method of introducing an aqueous solution of a required amount of a metal compound into a reaction vessel during grain formation, or a silver halide preparation There is a method of adding and dissolving another silver halide grain which has been previously doped with metal ions or complex ions. In particular, a method of adding an aqueous solution of a metal compound powder or an aqueous solution in which a metal compound and NaCl, KCl are dissolved together is added to the water-soluble halide solution. When added to the particle surface, a necessary amount of an aqueous solution of a metal compound can be charged into the reaction vessel immediately after the formation of the particle, during or after physical ripening, or at the time of chemical ripening.
[0040]
The photosensitive silver halide grains used in the present invention can be desalted by a known desalting method such as a noodle method, a flocculation method, an ultrafiltration method, or an electrodialysis method.
[0041]
The photosensitive silver halide grains used in the present invention are preferably chemically sensitized. Known sensitization methods such as sulfur sensitization, selenium sensitization, tellurium sensitization, noble metal sensitization and reduction sensitization can be used as sensitization methods. Sensitive methods can be used. These sensitization methods can be used in combination of two or more. For sulfur sensitization, thiosulfate, thiourea compounds, inorganic sulfur, and the like can be used. Examples of compounds preferably used for selenium sensitization and tellurium sensitization include compounds described in JP-A-9-230527. Examples of the compound preferably used for the noble metal sensitization include chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide, US Pat. No. 2,448,060, British Patent 618,061. And the like. As a shell-like compound in the reduction sensitization method, ascorbic acid, thiourea dioxide, stannous chloride, hydrazine derivative, borane compound, silane compound, polyamine compound and the like can be used. Further, reduction sensitization can be performed by ripening the emulsion while maintaining the pH at 7 or higher or the pAg at 8.3 or lower.
[0042]
Photothermographic materials used in the present invention include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, styryl dyes, hemicyanine dyes, oxonol dyes, hemioxonol dyes as spectral sensitizing dyes. Can be used. For example, JP-A-63-159841, JP-A-60-140335, JP-A-63-231437, JP-A-63-259651, JP-A-63-304242, JP-A-63-15245, U.S. Pat. Nos. 4,740,455, 4,741,966, 4,751,175, and 4,835,096 can be used. Useful sensitizing dyes used in the present invention are described in, for example, the literature described or cited in Research Disclosure Item 17643IV-A (December 1978, p.23), Item 18431 (August 1979, p.437). Has been. In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of various laser imagers and scanner light sources can be advantageously selected. For example, compounds described in JP-A Nos. 9-34078, 9-54409, and 9-80679 are preferably used.
[0043]
Useful cyanine dyes are cyanine dyes having basic nuclei such as thiazoline nucleus, oxazoline nucleus, pyrroline nucleus, pyridine nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus and imidazole nucleus. In addition to the basic nuclei described above, preferred merocyanine dyes include acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidinedione nucleus, thiazolinedione nucleus, barbituric acid nucleus, thiazolinone nucleus, malononitrile nucleus, and pyrazolone nucleus. Including.
[0044]
These sensitizing dyes may be used alone or in combination. The combination of sensitizing dyes is often used particularly for the purpose of supersensitization. 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. Useful sensitizing dyes, combinations of dyes exhibiting supersensitization, and substances exhibiting supersensitization are described in Research Disclosure (Research Disclosure) 176, 17643 (published December 1978), page 23, 1V, or No. 43-4933, JP-A Nos. 59-19032, 59-192242 and the like.
[0045]
The organic silver salt used in the present invention is a reducible silver source, and a silver salt of an organic acid and a heteroorganic acid containing a reducible silver ion source, particularly a long chain (10-30, preferably 15-28 A silver salt of an aliphatic carboxylic acid having a carbon number) is preferred.
[0046]
Also useful are organic or inorganic silver salt complexes in which the ligand has a complex stability constant for silver ions of 4.0-10.0. For example: silver salts of organic acids (eg gallic acid, oxalic acid, behenic acid, stearic acid, palmitic acid, lauric acid, oleic acid, caproic acid, myristic acid, palmitic acid, maleic acid, linoleic acid Silver carboxyalkylthiourea salts (eg, 1- (3-carboxypropyl) thiourea, 1- (3-carboxypropyl) -3,3-dimethylthiourea, etc.); aldehydes and hydroxy-substituted aromatic carboxylic acids Silver complexes of polymer reaction products with acids (eg, aldehydes (formaldehyde, acetaldehyde, butyraldehyde, etc.), hydroxy-substituted acids (eg, salicylic acid, benzoic acid, 3,5-dihydroxybenzoic acid, 5,5-thiodi) Salicylic acid), silver salts or complexes of thioenes (eg 3- (2-carboxyethyl) -4-hydroxymethyl-4- (thiazoline-2-thioene, and 3-carboxymethyl-4-thiazoline-2-thioene), imidazole, pyrazole, urazole, 1,2,4-thiazole and 1H-tetrazole, 3- Nitric acid and silver complexes or salts selected from amino-5-benzylthio-1,2,4-triazole and benzotriazole; silver salts such as saccharin and 5-chlorosalicylaldoxime; and silver salts of mercaptides. Examples of suitable silver salts are described in Research Disclosure Nos. 17029 and 29963, and a particularly preferred silver source is silver behenate.
[0047]
The organic silver salt compound can be obtained by mixing a water-soluble silver compound and a compound that forms a complex with silver. As described in Japanese Patent Application Laid-Open No. 9-127643, a normal mixing method, a reverse mixing method, and a simultaneous mixing method are used. A controlled double jet method is preferable.
[0048]
The shape of the organic silver salt that can be used in the present invention is not particularly limited, but needle crystals having a short axis and a long axis are preferred. As is well known in the light-sensitive silver halide light-sensitive material, the inversely proportional relationship between the size of the silver salt crystal grains and the covering power is also established in the heat-developable light-sensitive material of the present invention. When the organic silver salt particles as the image forming portion are large, the covering power is small and the image density is low. Therefore, it is necessary to reduce the size of the organic silver salt. In the present invention, a short axis of 0.01 μm to 0.20 μm and a long axis of 0.10 μm to 5.0 μm are preferable, and a short axis of 0.01 μm to 0.15 μm and a long axis of 0.10 μm to 4.0 μm are more preferable. The particle size distribution of the organic silver salt is preferably monodispersed. Monodispersion is preferably a percentage of a value obtained by dividing the standard deviation of the lengths of the short axis and the long axis by the short axis and the long axis, respectively, preferably 100% or less, more preferably 80% or less, and even more preferably 50% or less. Is good. The method for measuring the shape of the organic silver salt can be determined from a transmission electron microscope image of the organic silver salt dispersion. As another method for measuring monodispersity, there is a method for obtaining the standard deviation of the volume-weighted average diameter of the organic silver salt, and the percentage (coefficient of variation) of the value divided by the volume-weighted average diameter is preferably 100% or less. Preferably it is 80% or less, More preferably, it is 50% or less. As a measuring method, for example, the organic silver salt dispersed in the liquid is irradiated with laser light, and the autocorrelation coefficient with respect to the temporal change of the fluctuation of the scattered light is obtained from the particle size (volume load average diameter). be able to. The coating amount of the organic silver salt, particularly the organic acid silver in the photosensitive material used in the present invention is 1 m of the photosensitive material.²0.5 to 5.0 g per unit is preferable, and 1.0 to 3.0 g is more preferable.
[0049]
Examples of the reducing agent suitable for the photothermographic material used in the present invention are US Pat. Nos. 3,770,448, 3,773,512, 3,593,863, and Research Disclosure No. 17029 and 29963, which include:
[0050]
Aminohydroxycycloalkenone compounds (eg, 2-hydroxypiperidino-2-cyclohexenone); aminoreductones esters (eg, piperidinohexose reductone monoacetate) as precursors of reducing agents; N— Hydroxyurea derivatives (eg Np-methylphenyl-N-hydroxyurea); aldehyde or ketone hydrazones (eg anthracene aldehyde phenylhydrazone); phosphoramidophenols; phosphoramidoanilines; polyhydroxybenzenes (Eg hydroquinone, t-butyl-hydroquinone, isopropylhydroquinone and (2,5-dihydroxy-phenyl) methylsulfone); sulfhydroxamic acids (eg benzenesulfhydroxam ); Sulfonamidoanilines (eg, 4- (N-methanesulfonamido) aniline); 2-tetrazolylthiohydroquinones (eg, 2-methyl-5- (1-phenyl-5-tetrazolylthio) hydroquinone); tetrahydro Quinoxalines (eg, 1,2,3,4-tetrahydroquinoxaline); amidoxins; azines (eg, a combination of aliphatic carboxylic acid arylhydrazides and ascorbic acid); a combination of polyhydroxybenzene and hydroxylamine; Hydroductic acids; combinations of azines and sulfonamidophenols; α-cyanophenylacetic acid derivatives; combinations of bis-β-naphthol and 1,3-dihydroxybenzene derivatives; 5-pyrazolones; sulfones Midphenol reducing agent; 2-phenylindane-1,3-dione and the like; chroman; 1,4-dihydropyridines (for example, 2,6-dimethoxy-3,5-dicarboethoxy-1,4-dihydropyridine); bisphenol (E.g., bis (2-hydroxy-3-tert-butyl-5-methylphenyl) methane, bis (6-hydroxy-m-tri) mesitol, 2,2-bis (4-hydroxy-3- Methylphenyl) propane, 4,5-ethylidene-bis (2-tert-butyl-6-methyl) phenol), UV-sensitive ascorbic acid derivatives and 3-pyrazolidones. Of these, particularly preferred reducing agents are hindered phenols. Examples of the hindered phenols include compounds represented by the following general formula (A).
[0051]
[Chemical 1]

[0052]
In the formula, R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (for example, butyl group, 2,4,4-trimethylpentyl group, etc.), and R ′ and R ″ are alkyl having 1 to 5 carbon atoms. Represents a group (for example, a methyl group, an ethyl group, a t-butyl group, etc.).
[0053]
Specific examples of the compound represented by formula (A) are shown below. However, the present invention is not limited to these.
[0054]
[Chemical formula 2]

[0055]
[Chemical Formula 3]

[0056]
The amount of reducing agent used, including the compound represented by the general formula (A), is preferably 1 × 10 5 per mole of silver.^-2-10 mol, especially 1 x 10^-2~ 1.5 mol.
[0057]
In the present invention, it is preferable to contain a matting agent on the photosensitive layer side, and in order to prevent scratches on the image after heat development, it is preferable to dispose the matting agent on the surface of the photosensitive material. The content is preferably 0.5 to 10% by weight with respect to the total binder on the emulsion layer side.
[0058]
The material of the matting agent used in the present invention may be either organic or inorganic. Examples of inorganic substances include silica described in Swiss Patent No. 330,158 and the like, glass powder described in French Patent No. 1,296,995 and the like, and alkali described in British Patent No. 1,173,181 and the like. Earth metals or carbonates such as cadmium and zinc can be used as the matting agent. Examples of organic substances include starch described in U.S. Pat. No. 2,322,037 and the like, starch derivatives described in Belgian Patent 625,451 and British Patent 981,198, and Japanese Patent Publication No. 44-3643. Polyvinyl alcohol described, polystyrene or polymethacrylate described in Swiss Patent No. 330,158, polyacrylonitrile described in US Pat. No. 3,079,257, US Pat. No. 3,022,169 etc. An organic matting agent such as a polycarbonate can be used.
[0059]
The shape of the matting agent may be either a regular shape or an irregular shape, but is preferably a regular shape, and a spherical shape is preferably used. The size of the matting agent is represented by a diameter when the volume of the matting agent is converted into a sphere. In the present invention, the particle size of the matting agent indicates the diameter converted into a spherical shape.
[0060]
The matting agent used in the present invention preferably has an average particle size of 0.5 μm to 10 μm, more preferably 1.0 μm to 8.0 μm. The coefficient of variation of the particle size distribution is preferably 50% or less, more preferably 40% or less, and particularly preferably 30% or less.
[0061]
Here, the variation coefficient of the particle size distribution is a value represented by the following equation.
[0062]
(Standard deviation of particle size) / (Average value of particle size) × 100
The matting agent used in the present invention can be contained in any constituent layer, but in order to achieve the object of the present invention, it is preferably a constituent layer other than the photosensitive layer, and more preferably viewed from the support. The outermost layer.
[0063]
The method for adding the matting agent used in the present invention may be a method in which the matting agent is dispersed and applied in advance in the coating solution, or a method in which the matting agent is sprayed after the coating solution is applied and before drying is completed. It may be used. When a plurality of types of matting agents are added, both methods may be used in combination.
[0064]
The photothermographic material used in the present invention forms a photographic image by heat development processing, and is a reducible non-photosensitive silver source (organic silver salt), a catalytically active amount of photosensitive silver halide, hydrazine. The photothermographic material preferably contains a derivative, a reducing agent, and, if necessary, a color toning agent that suppresses the color tone of silver in a dispersed state in a normal (organic) binder matrix. The photothermographic material used in the present invention is stable at room temperature, but is developed by heating to a high temperature (for example, 80 ° C. to 140 ° C.) after exposure. By heating, silver is generated through an oxidation-reduction reaction between an organic silver salt (functioning as an oxidizing agent) and a reducing agent. This redox reaction is promoted by the catalytic action of the latent image generated in the silver halide upon exposure. The silver produced by the reaction of the organic silver salt in the exposed areas provides a black image that contrasts with the unexposed areas and forms an image. This reaction process proceeds without supplying a treatment liquid such as water from the outside.
[0065]
The photothermographic material used in the present invention has at least one photosensitive layer on a support. Although only the photosensitive layer may be formed on the support, it is preferable to form at least one non-photosensitive layer on the photosensitive layer. In order to control the amount of light passing through the photosensitive layer or the wavelength distribution, a filter layer may be formed on the same side or the opposite side of the photosensitive layer, or a dye or pigment may be included in the photosensitive layer. . As the dye, the compound described in Japanese Patent Application No. 7-11184 is preferable. The photosensitive layer may be composed of a plurality of layers, and the sensitivity may be a high sensitivity layer / a low sensitivity layer or a low sensitivity layer / a high sensitivity layer for gradation adjustment. Various additives may be added to any of the photosensitive layer, the non-photosensitive layer, and other forming layers. For the photothermographic material used in the present invention, for example, surfactants, antioxidants, stabilizers, plasticizers, ultraviolet absorbers, coating aids and the like may be used.
[0066]
It is preferable to add a color toner to the photothermographic material used in the present invention. Toning agents are materials well known in the photographic art as shown in US Pat. Nos. 3,080,254, 3,847,612 and 4,123,282. Examples of suitable toning agents are disclosed in Research Disclosure No. 17029 and include:
[0067]
Imides (eg, phthalimide); cyclic imides, pyrazolin-5-ones, and quinazolinones (eg, succinimide, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline, and 2,4- Thiazolidinediones); naphtholimides (eg, N-hydroxy-1,8-naphtholimide); cobalt complexes (eg, hexamine trifluoroacetate of cobalt), mercaptans (eg, 3-mercapto-1,2,4- Triazoles); N- (aminomethyl) aryl dicarboximides (eg N- (dimethylaminomethyl) phthalimide); combinations of blocked pyrazoles, isothiuronium derivatives and certain photobleaching agents (eg N, N'-F A combination of Samethylene (1-carbamoyl-3,5-dimethylpyrazole), 1,8- (3,6-dioxaoctane) bis (isothiuronium trifluoroacetate), and 2- (tribromomethylsulfonyl) benzothiazole ); Merocyanine dyes (e.g. 3-ethyl-5-((3-ethyl-2-benzothiazolinylidene (benzothiazolinylidene))-1-methylethylidene) -2-thio-2,4-oxazolidine Dione); phthalazinone, phthalazinone derivatives or metal salts of these derivatives (eg, 4- (1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-dimethyloxyphthalazinone, and 2,3-dihydro-1 , 4-phthalazinedione); a combination of phthalazinone and a sulfinic acid derivative (for example, 6 Chlorophthalazinone + sodium benzenesulfinate or 8-methylphthalazinone + sodium p-trisulfonate); phthalazine + phthalic acid combination; phthalazine (including adducts of phthalazine) and maleic anhydride, and phthalic acid, 2 , 3-Naphthalenedicarboxylic acid or o-phenylene acid derivatives and their anhydrides (for example, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride) in combination with at least one compound Quinazolinediones, benzoxazines, naloxazine derivatives; benzoxazine-2,4-diones (eg, 1,3-benzoxazine-2,4-dione); pyrimidines and asymmetric-triazines (eg, 2, 4-dihydroxypyrimidine) and tet Laazapentalene derivatives (for example, 3,6-dimercapto-1,4-diphenyl-1H, 4H-2,3a, 5,6a-tetraazapentalene). Preferred toning agents are phthalazone or phthalazine.
[0068]
In the present invention, a mercapto compound, a disulfide compound, and a thione compound can be contained in order to suppress or promote development and control development, to improve spectral sensitization efficiency, and to improve storage stability before and after development. . When a mercapto compound is used in the present invention, any structure may be used, but those represented by ArSM and Ar-SS-Ar are preferred. In the formula, M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring or condensed aromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, the heteroaromatic ring is benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzoterzole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine , Pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring has, for example, a halogen atom (for example, Br and Cl), a hydroxyl group, an amino group, a carboxyl group, an alkyl group (for example, one or more carbon atoms, preferably 1 to 4 carbon atoms) And an alkoxyl group (for example, one having one or more carbon atoms, preferably one having 1 to 4 carbon atoms). Mercapto-substituted heteroaromatic compounds include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzimidazole, 6-ethoxy-2-mercaptobenzothiazole, 2,2 '-Dithiobisbenzothiazole, 3-mercapto-1,2,4-triazole, 4,5-diphenyl-2-imidazolethiol, 2-mercaptoimidazole, 1-ethyl-2-mercaptobenzimidazole, 2-mercaptoquinoline, 8-mercaptopurine, 2-mercapto-4- (3H) quinazolinone, 7-trifluoromethyl-4-quinolinethiol, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-amino-6-hydroxy -2-Mercaptopirimi Monohydrate, 2-amino-5-mercapto-1,3,4-thiadiazole, 3-amino-5-mercapto-1,2,4-triazole, 4-hydroxy-2-mercaptopyrimidine, 2-mercaptopyrimidine, 4, Examples include 6-diamino-2 mercaptopyrimidine, 2-mercapto-4-methylpyrimidine hydrochloride, 3-mercapto-5-phenyl-1,2,4-triazole, and 2-mercapto-4-phenyloxazole. The invention is not limited to these.
[0069]
The amount of the mercapto compound described above is preferably 0.001 to 1.0 mol per mol of silver in the emulsion layer, and more preferably 0.01 to 0.3 mol per mol of silver.
[0070]
Mercury ions are known as the most effective antifoggants. The use of a mercury compound as an antifoggant in a light-sensitive material is disclosed in, for example, US Pat. No. 3,589,903. However, mercury compounds are environmentally undesirable. As the non-mercury antifoggant, for example, antifoggants as disclosed in US Pat. Nos. 4,546,075 and 4,452,885 and JP-A-59-57234 are preferable.
[0071]
Particularly preferred non-mercury antifoggants include compounds such as those disclosed in US Pat. Nos. 3,874,946 and 4,756,999, —C (X₁) (X₂) (X_Three) (Where X₁And X₂Represents a halogen atom and X_ThreeRepresents a hydrogen or halogen atom), and a heterocyclic compound having one or more substituents represented by. As examples of suitable antifoggants, compounds described in paragraphs [0062] to [0063] of JP-A-9-90550 are preferably used.
[0072]
Further, more suitable antifoggants are disclosed in US Pat. No. 5,028,523 and European Patent Nos. 600,587, 605,981, 631,176, and the like.
[0073]
In the photosensitive layer according to the present invention, polyhydric alcohols (for example, glycerol and diol of the type described in US Pat. No. 2,960,404), 2,588,765 and the like are used as plasticizers and lubricants. Fatty acids or esters described in 3,121,060, silicone resins described in British Patent 955,061, and the like can be used.
[0074]
A hardener may be used for each layer such as the photosensitive layer, protective layer, and back layer used in the present invention. Examples of the hardener include isocyanate compounds, US Pat. No. 4,791,042 and the like. Epoxy compounds, vinyl sulfone compounds described in JP-A No. 62-89048, and the like are used.
[0075]
In the present invention, a surfactant may be used for the purpose of improving coating properties and charging. As examples of the surfactant, any of anionic, cationic, betaine, nonionic, fluorine and the like can be used as appropriate. Specifically, fluoropolymer surfactants described in JP-A-62-170950, US Pat. No. 5,382,504, JP-A-60-244945, JP-A-63-188135, etc. Fluorinated surfactants described in US Pat. No. 3,885,965 and the like, polyalkylene oxides and anionic surfactants described in JP-A-6-301140, and the like. Can be mentioned.
[0076]
The photographic emulsion for heat development in the present invention is subjected to various coating methods including a dip coating method, an air knife coating method, a flow coating method, or an extrusion coating method using a hopper of the type described in US Pat. No. 2,681,294. Can be used. If desired, two or more layers can be applied simultaneously by the methods described in US Pat. No. 2,761,791 and British Patent No. 837,095.
[0077]
The support used in the present invention is a plastic film (for example, polyethylene terephthalate, polycarbonate, polyimide, nylon, cellulose triacetate, polyethylene naphthalate) to obtain a predetermined optical density after development processing and to prevent deformation of the image after development processing. Phthalate).
[0078]
Among them, preferable supports are polyethylene terephthalate (hereinafter abbreviated as PET), polyethylene naphthalate (hereinafter abbreviated as PEN), and a plastic support (hereinafter abbreviated as SPS) including a styrene polymer having a syndiotactic structure. Is mentioned. The thickness of the support is about 50 to 300 μm, preferably 70 to 180 μm.
[0079]
A heat-treated plastic support can also be used. Examples of the plastic to be used include the plastics described above. The heat treatment of the support is a temperature higher than the glass transition point of the support by 30 ° C. or more, preferably 35 ° C. or more, after these supports are formed and before the photosensitive layer is applied, More preferably, heating is performed at a temperature higher by 40 ° C. or more. However, the effect of the present invention cannot be obtained by heating at a temperature exceeding the melting point of the support.
[0080]
Next, the plastic used will be described.
[0081]
PET is composed of polyethylene terephthalate as a component of polyester. However, in addition to polyethylene terephthalate, terephthalic acid, naphthalene-2,6-dicarboxylic acid, isophthalic acid, butylene dicarboxylic acid, 5-sodium sulfoisophthalic acid, It may be a polyester in which a modified polyester component such as adipic acid or the like and ethylene glycol, propylene glycol, butanediol, cyclohexanedimethanol or the like as a glycol component is contained in an amount of 10 mol% or less of the total polyester.
[0082]
PEN is preferably polyethylene 2,6 naphthalate, a copolyester composed of terephthalic acid, 2-6 naphthalene dicarboxylic acid and ethylene glycol, and a polyester mainly composed of a mixture of two or more of these polyesters. Further, other copolymer components may be copolymerized or other polyesters may be mixed.
[0083]
Unlike ordinary polystyrene (atactic polystyrene), SPS is a polystyrene having three-dimensional regularity. The regular stereoregular structure portion of SPS is called a racemo chain, and it is preferable that there are more regular portions such as a 2-chain, 3-chain, 5-chain or more. In the present invention, the racemo-chain is 2 It is preferably 85% or more in the chain, 75% or more in the 3 chain, 50% or more in the 5 chain, and 30% or more in the further chain. The polymerization of SPS can be carried out according to the method described in JP-A-3-131443.
[0084]
A known method can be used for the film-forming method and the undercoating method for the support used in the present invention. Preferably, the methods described in paragraphs [0030] to [0070] of JP-A-9-50094 are used. Is to use.
[0085]
Next, the silver halide photographic light-sensitive material used in the present invention will be described.
[0086]
The film thickness of the emulsion layer of the silver halide photographic light-sensitive material used in the present invention is 0.5 to 2. in order to improve the sharpness of X-ray image information and to have sufficient diagnostic ability for cancer and the like. Although it is necessary that the film thickness is 0 μm, 0.7 to 1.5 μm is more preferable in order to further improve the diagnostic ability. The film thickness of the emulsion layer means the film thickness of one emulsion layer on one side in the case of having emulsion layers on both sides of the support, and the total film thickness in the case of multiple emulsion layers on one side. Say.
[0087]
The film thickness can be calculated using an electron micrograph of the cross section of the photosensitive material after being left in an atmosphere of 23 ° C. and 50% RH for at least 2 hours. Moreover, in order to make said film thickness, it can adjust with the amount of binders.
[0088]
The emulsion used for the silver halide photographic light-sensitive material used in the present invention can be produced by a known method. The crystal habit may have a spherical shape, for example, a cube, a tetrahedron, an octahedron, a (111) plane, and a (100) plane.
[0089]
The crystal structure of the silver halide may be composed of silver halide compositions having different inside and outside. Examples thereof include internal high-iodine type monodisperse particles disclosed in JP-A-2-85846.
[0090]
Furthermore, it is preferable to use tabular grains having an average aspect ratio of 2 or more in the present invention, and the aspect ratio is more preferably 3 to 20.
[0091]
In the present invention, the aspect ratio refers to the ratio of the diameter (particle diameter) to the thickness of the main plane of tabular grains. The diameter of the main plane of the tabular grain means the diameter of a circle having an area equal to the projected area of the main plane. In the present invention, the diameter of the main plane of the tabular silver halide grains is preferably 0.05 to 2.0 μm, more preferably 0.1 to 1.5 μm, and particularly preferably 0.15 to 1.0 μm.
[0092]
In general, tabular silver halide grains are tabular having two parallel major planes. Therefore, “thickness” in the present invention is a distance between two parallel major planes constituting the tabular silver halide grains. expressed.
[0093]
Advantages of the tabular grains used in the present invention are that spectral sensitization efficiency is improved, image graininess and sharpness are improved, for example, British Patent No. 2,112,157, US Pat. No. 4,439,520, No. 4,433,048, No. 4,414,310, No. 4,434,226, JP-A Nos. 58-113927, 58-127721, 63- 138342, 63-284272, 63-305343 and the like, and emulsions can be prepared by the methods described in these publications.
[0094]
Further, a flat plate having a (100) main plane described in US Pat. Nos. 4,063,951, 4,386,156, 5,275,930, and 5,314,798. Shaped particles are also preferably used.
[0095]
More preferred silver halide emulsions for use in the present invention are silver iodobromide, silver iodochlorobromide, silver bromide, silver chlorobromide and silver chloride in an amount of less than 3 mol% of silver iodide, particularly preferably iodine. Silver bromide, silver iodobromide or silver iodochloride having a silver chloride content of less than 1.0 mol%. The emulsion described above may be either a surface latent image type that forms a latent image on the grain surface, an internal latent image type that forms a latent image inside the grain, or a type that forms a surface and an internal latent image.
[0096]
The silver halide emulsion used in the present invention is preferably monodispersed, and those having a coefficient of variation of the average volume particle diameter within 20%, particularly within 10% are preferably used. In the present invention, in the case of tabular grains, the average volume particle diameter is the length of one side of a cube in which the volume of each grain is converted by converting the volume of the tabular grains into the volume of a cube having the same volume. Say average. The same applies to particles having other shapes. In addition, you may mix and use the above-mentioned cube and tetradecahedral grain and tabular grain.
[0097]
A method in which at least one monodispersed emulsion having a coefficient of variation in average volume particle diameter within 10% is used, and two or more emulsions are mixed and used is preferable. Further, among the plural emulsions to be mixed, a tabular emulsion is used as the most sensitive emulsion and a cubic emulsion is used as the least sensitive emulsion.
[0098]
The silver halide grains used in the present invention include metal ions, metal complexes or metal selected from Fe, Co, Ru, Rh, Re, Os, and Ir as in the case of the silver halide grains of the photothermographic material. It is preferable to contain a complex ion, and one kind or two or more kinds of the same or different metal complexes may be used in combination. The same applies to the content in the silver halide grains, and preferred specific examples thereof are also the same as the hexacoordinate metal complex ions used in the silver halide grains of the photothermographic material.
[0099]
The emulsion may be subjected to a water washing method such as a noodle water washing method, a flocculation sedimentation method, or an ultrafiltration method in order to remove soluble salts. Preferable washing methods include, for example, a method using an aromatic hydrocarbon-based aldehyde resin containing a sulfo group described in JP-B-35-16086, or agglomerated polymer agent exemplified G3, G8 described in JP-A-63-158644 Is a particularly preferred desalting method.
[0100]
The photosensitive silver halide grains in the present invention are preferably chemically sensitized. Known sensitization methods such as sulfur sensitization, selenium sensitization, tellurium sensitization, noble metal sensitization and reduction sensitization are used as sensitization methods. Can be used.
[0101]
These sensitization methods can be used in combination of two or more. For sulfur sensitization, thiosulfate, thiourea compounds, inorganic sulfur, and the like can be used. Examples of the compound preferably used for selenium sensitization and tellurium sensitization include compounds described in JP-A-9-230527. Examples of the compound preferably used for the noble metal sensitization include chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide, US Pat. No. 2,448,060, and British Patent 618,061. And the like.
[0102]
As specific compounds for the reduction sensitization method, ascorbic acid, dithiothiourea, stannous chloride, hydrazine derivatives, borane compounds, silane compounds, polyamine compounds and the like can be used. Further, reduction sensitization can be performed by ripening the emulsion while maintaining the pH at 7 or higher or the pAg at 8.3 or lower.
[0103]
The silver halide photographic light-sensitive material used in the present invention includes a cyanine dye, a merocyanine dye, a complex cyanine dye, a complex merocyanine dye, a holopolar cyanine dye, a styryl dye, a hemicyanine dye, an oxonol dye, and a hemioxonol as spectral sensitizing dyes. A pigment | dye etc. can be used. For example, JP-A-63-159841, JP-A-60-140335, JP-A-63-231437, JP-A-63-259651, JP-A-63-304242, JP-A-63-15245, U.S. Pat. Nos. 4,740,455, 4,741,966, 4,751,175, and 4,835,096 can be used.
[0104]
Useful sensitizing dyes used in the present invention are described in, for example, the literature described or cited in Research Disclosure Item 17643IV-A (December 1978, p.23) and Item 18431 (August 1979, p.437). ing.
[0105]
In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of various laser imagers and scanner light sources can be advantageously selected. For example, compounds described in JP-A Nos. 9-34078, 9-54409, and 9-80679 are preferably used. Useful cyanine dyes are, for example, cyanine dyes having basic nuclei such as thiazoline nucleus, oxazoline nucleus, pyrroline nucleus, pyridine nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus and imidazole nucleus. Useful merocyanine dyes are preferably acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidinedione nucleus, thiazolinedione nucleus, barbituric acid nucleus, thiazolinone nucleus, malononitrile nucleus and pyrazolone nucleus in addition to the above basic nucleus. Including.
[0106]
The sensitizing dyes described above may be used alone or in combination, and the combination of sensitizing dyes is often used for the purpose of supersensitization. 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.
[0107]
Useful sensitizing dyes, combinations of dyes exhibiting supersensitization, and substances exhibiting supersensitization are described in Research Disclosure (Research Disclosure) 176, 17643 (published December 1978), page J, or JP-B-9-25500, JP-A-43-4933, JP-A-59-19032, JP-A-59-192242 and the like.
[0108]
The spectral sensitizing dye can be added as a solution dissolved in an organic solvent such as methanol. Further, a solid fine particle dispersion can be prepared and added. The addition amount of the spectral sensitizing dye is not uniform depending on the kind of the dye and the emulsion conditions, but is preferably 1 to 900 mg, more preferably 5 to 400 mg per mole of silver halide. The spectral sensitizing dye is preferably added before the end of the chemical ripening step, and may be added in several portions before the end of the chemical ripening. More preferably, it is after the completion of the silver halide grain growth step and before the chemical ripening step, and particularly preferably before the start of chemical ripening.
[0109]
In the present invention, in order to stop chemical sensitization (chemical ripening), it is preferable to use a chemical ripening stopper in consideration of the stability of the emulsion. The chemical ripening terminator includes halides (for example, potassium bromide, sodium chloride, etc.), organic compounds known as antifoggants or stabilizers (for example, 4-hydroxy-6-methyl-1,3, 3a, 7-tetrazaindene) and the like. These may be used alone or in combination of a plurality of compounds.
[0110]
In the emulsion of the light-sensitive material used in the present invention, various photographic additives can be used in the steps before and after physical ripening or chemical ripening.
[0111]
The support used in the present invention is a plastic film (for example, polyethylene terephthalate, polycarbonate, polyimide, nylon, cellulose triacetate, polyethylene naphthalate) to obtain a predetermined optical density after development processing and to prevent deformation of the image after development processing. Phthalate).
[0112]
Among them, preferable supports are polyethylene terephthalate (hereinafter abbreviated as PET), polyethylene naphthalate (hereinafter abbreviated as PEN), and a plastic support (hereinafter abbreviated as SPS) including a styrene polymer having a syndiotactic structure. Is mentioned. The thickness of the support is preferably about 50 to 300 μm, more preferably 70 to 180 μm.
[0113]
A heat-treated plastic support can also be used. Examples of the plastic to be used include the plastics described above. The heat treatment of the support is a temperature higher than the glass transition point of the support by 30 ° C. or more, preferably 35 ° C. or more, after these supports are formed and before the photosensitive layer is applied, More preferably, heating is performed at a temperature higher by 40 ° C. or more. However, the effect of the present invention cannot be obtained by heating at a temperature exceeding the melting point of the support.
[0114]
Next, the plastic used in the present invention will be described.
[0115]
PET is composed of polyethylene terephthalate as a component of polyester. However, in addition to polyethylene terephthalate, terephthalic acid, naphthalene-2,6-dicarboxylic acid, isophthalic acid, butylene dicarboxylic acid, 5-sodium sulfoisophthalic acid, It may be a polyester in which a modified polyester component such as adipic acid or the like and ethylene glycol, propylene glycol, butanediol, cyclohexanedimethanol or the like as a glycol component is contained in an amount of 10 mol% or less of the total polyester.
[0116]
Examples of PEN include polyethylene 2,6-naphthalate, copolyester composed of terephthalic acid, 2,6-naphthalenedicarboxylic acid and ethylene glycol, and a polyester mainly composed of a mixture of two or more of these polyesters. preferable. Further, other copolymer components may be copolymerized or other polyesters may be mixed.
[0117]
Unlike ordinary polystyrene (atactic polystyrene), SPS is a polystyrene having three-dimensional regularity. The regular stereoregular structure part of SPS is called a racemo chain, and it is preferable that there are more regular parts such as a 2-chain, 3-chain, 5-chain or more. In the present invention, the racemo-chain is 2 It is preferably 85% or more in the chain, 75% or more in the 3 chain, 50% or more in the 5 chain, and 30% or more in the further chain. The polymerization of SPS can be carried out according to the method described in JP-A-3-131443.
[0118]
A known method can be used for the film-forming method and the undercoating method for the support used in the present invention. Preferably, the methods described in paragraphs [0030] to [0070] of JP-A-9-50094 are used. Is to use.
[0119]
In order that the silver halide photographic light-sensitive material used in the present invention is suitable for rapid processing, an appropriate amount of a hardener is added in advance in the light-sensitive material coating step, and the water swelling rate in the development-fixing-water-washing step. It is preferable to reduce the water content in the photosensitive material before the start of drying by adjusting. In the light-sensitive material of the present invention, the swelling ratio during development is preferably 50 to 150%, and the film thickness after swelling is preferably 20 μm or less. If the water swell ratio exceeds 150%, drying failure occurs. For example, in the automatic processor processing, particularly rapid processing, conveyance failure also occurs. Also, if the water swell ratio is less than 50%, development unevenness and residual color are generated during development. There is a bad tendency to increase. The water swelling rate mentioned here refers to the difference between the film thickness after swelling in each processing solution and the film thickness before development processing, divided by the film thickness before processing and multiplied by 100. .
[0120]
In the silver halide photographic light-sensitive material of the present invention, various additives can be further added to the silver halide emulsion depending on the purpose. Examples of additives and the like used include those described in RD-17643 (December 1978), 18716 (November 1979) and 308119 (December 1989). These are listed below.
[0121]

In the process of developing the silver halide photographic light-sensitive material used in the present invention, powder processing agents, solid processing agents such as tablets, pills, granules, etc. may be used, and further moisture-proof processing is applied if necessary. May be used.
[0122]
The powder used in the present invention refers to an aggregate of fine crystals. The granule referred to in the present invention is a powder obtained by adding a granulation step, and means a granular material having a particle size of 50 to 5000 μm. The tablet referred to in the present invention means a powder or granule that is compression-molded into a certain shape.
[0123]
In order to keep the photographic performance stable, it is effective to reduce the opening coefficient of the developer in the automatic processor. Especially the opening coefficient is 50cm²/ Liter or less is preferable. That is, the opening coefficient is 50 cm²If the amount exceeds / liter, the undissolved solid treatment agent or the concentrated liquid immediately after dissolution is susceptible to air oxidation. As a result, insoluble matter and scum are generated, contaminating the actual machine or the sensitive material to be treated, etc. A problem occurs, but the aperture coefficient is 50m²These problems are solved at less than 1 / liter. In the present invention, the opening coefficient is represented by a contact area with air per unit volume of the processing liquid, and the unit is (cm²/ Liter).
[0124]
In the present invention, the opening coefficient of the automatic processor is 50 cm.²/ Liter or less, more preferably 30-3 cm²/ Liter, particularly preferably 20 to 5 cm²/ Liter. The opening coefficient is generally reduced by using a resin or the like that blocks air as a floating lid, or by using a slit type developing device described in JP-A Nos. 63-131138, 63-212050, and 63-235940. it can.
[0125]
The solid processing agent used in the present invention is used for a photographic processing agent such as a developer, a fixing agent and a stabilizer. The solid processing agent used in the present invention may solidify only one part of the component of a certain processing agent, but preferably all the components of the processing agent are solidified. It is desirable that each component is molded as a separate solid processing agent and is individually packaged. It is also desirable that the different components are packaged in the order in which they are periodically fed repeatedly.
[0126]
In the present invention, as the supply means for supplying the solid processing agent to the processing tank, for example, when the solid processing agent is a tablet, Japanese Utility Model Laid-Open Nos. 63-137783, 63-97522 and 1-85732 are disclosed. There are known methods such as a gazette, but in short, any method may be used as long as the function of supplying tablets to the treatment tank is provided at a minimum.
[0127]
In the case where the solid processing agent is a granule or a powder, a gravity dropping method described in Japanese Utility Model Laid-Open Nos. 62-81964 and 63-84151 and Japanese Patent Application Laid-Open No. 1-292375, and Japanese Utility Model Laid-Open Nos. 63-105159 and 63. A method using a screw or a screw described in No. 195345 is a known method, but is not limited thereto.
[0128]
In addition to the dihydroxybenzenes, aminophenols and pyrazolidones described in JP-A-6-138593 (pages 19 to 20), the reductones described in JP-A-5-165161 are also preferred among the developers. Used. Of the pyrazolidones used, those substituted at the 4-position (dimezone, dimezone S, etc.) are particularly preferred because they are less soluble in water and change with time of the solid treatment agent itself. In addition to sulfites, organic reducing agents can be used as preservatives as preservatives. In addition, bisulfite adducts of chelating agents and hardeners can be added. It is also preferable to add compounds described in JP-A-5-289255 and JP-A-6-308680 (general formulas [4-a] and [4-b]) as silver sludge inhibitors.
[0129]
Addition of a cyclodextrin compound is also preferable, and a compound described in JP-A 1-124853 is particularly preferable. An amine compound can also be added to the developer, and the compounds described in US Pat. No. 4,269,929 are particularly preferred.
[0130]
It is necessary to use a buffer for the developer. Examples of the buffer include sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, trisodium phosphate, tripotassium phosphate, dipotassium phosphate, boric acid. Sodium, potassium borate, sodium tetraborate, potassium tetraborate, sodium o-hydroxybenzoate, potassium o-hydroxybenzoate, sodium 5-sulfo-2-hydroxybenzoate (sodium 5-sulfosalicylate), 5- Examples include potassium sulfo-2-hydroxybenzoate.
[0131]
Examples of the development accelerator are described in JP-B-37-16088, JP-A-37-5987, JP-A-38-7826, JP-A-44-12380, JP-A-45-9019, and U.S. Pat. No. 3,813,247. Thioether compounds, p-phenylenediamine compounds described in JP-A-52-49829 and JP-A-50-15554, JP-A-50-137726, JP-B-44-30074, JP-A-56-156826 And quaternary ammonium salts described in US Pat. No. 52-43429, p-aminophenols described in US Pat. Nos. 2,610,122 and 4,119,462, US Pat. No. 2,494,903 No. 3,128,182, No. 4,230,796, No. 3,253,919, Japanese Patent Publication No. 41-11431, US Pat. No. 2,482,5 No. 6, No. 2,596,926 and No. 3,582,346, etc., Japanese Patent Publication No. 37-16088, No. 42-25201, US Pat. No. 3,128,183 And polyalkylene oxides described in JP-B Nos. 41-11431, 42-2383 and U.S. Pat. No. 3,532,501, other 1-phenyl-3-pyrazolidones, hydrazines, mesoionic compounds, imidazoles Etc. can be added as needed.
[0132]
As the antifoggant, alkali metal halides such as potassium bromide and organic antifoggants can be used. Examples of organic antifoggants include benzotriazole, 6-nitrobenzimidazole, 5-nitroisoindazole, 5-methylbenzotriazole, 5-nitrobenzotriazole, 5-chlorobenzotriazole, 2-thiazolylbenzimidazole, Examples include 2-thiazolylmethylbenzimidazole, indazole, hydroxyazaindolizine, adenine, 1-phenyl-5-mercaptotetrazole and the like. Further, in the developer composition, if necessary, methyl cellosolve, methanol, acetone, dimethylformamide, cyclodextrin compound, and other compounds described in JP-B-47-33378 and JP-A-44-9509 are used as developing agents. It can be used as an organic solvent for increasing the solubility. Furthermore, various additives such as other stain inhibitors and sludge inhibitors can be used.
[0133]
Prior to the treatment, it is also preferable to add a starter, and it is also preferable to solidify and add the starter. As the starter, in addition to an organic acid such as a polycarboxylic acid compound, an alkali metal halide such as KBr or an organic inhibitor, A development accelerator is used.
[0134]
The pH of the developer adjusted with the starter is preferably in the range of 9 to 12, more preferably in the range of 9.5 to 10.5. The development temperature is 20 to 60 ° C, preferably 30 to 45 ° C.
[0135]
Next, the fixing solution used in the present invention will be described. The fixer preferably contains thiosulfate. The thiosulfate is usually used as a lithium, potassium, sodium or ammonium salt, preferably sodium thiosulfate or ammonium thiosulfate. A fixing solution having a high fixing speed can be obtained by using an ammonium salt, but a sodium salt is preferable from the viewpoint of storage stability. The concentration of thiosulfate is preferably 0.1 to 5 mol / liter, more preferably 0.5 to 2 mol / liter, and still more preferably 0.7 to 1.8 mol / liter.
[0136]
In addition, iodide salts and thiocyanates can be used as fixing agents. The fixing solution preferably contains a sulfite, and the concentration of the sulfite is 0.2 mol / liter or less when the thiosulfate and the sulfite are dissolved and mixed in an aqueous solvent.
[0137]
As the sulfite, solid lithium, potassium, sodium, ammonium salt and the like are used, and dissolved together with the solid thiosulfate. The fixing solution used in the present invention may contain a water-soluble chromium salt or a water-soluble aluminum salt. Examples of the water-soluble chromium salt include chromium alum, and examples of the water-soluble aluminum salt include aluminum sulfate, potassium aluminum chloride, and aluminum chloride. The amount of chromium salt or aluminum salt added is 0.2 to 3.0 g, preferably 1.2 to 2.5 g, per liter of the fixing solution. The fixing agent may include acetic acid, citric acid, tartaric acid, malic acid, succinic acid, phenylacetic acid, and optical isomers thereof. These salts include, for example, potassium citrate, lithium citrate, sodium citrate, ammonium citrate, lithium hydrogen tartrate, potassium hydrogen tartrate, potassium tartrate, sodium hydrogen tartrate, sodium tartrate, ammonium hydrogen tartrate, potassium ammonium tartrate, Preferred examples include lithium, potassium, sodium, ammonium salts and the like typified by sodium potassium tartrate, sodium malate, ammonium malate, sodium oxalate, ammonium oxalate and the like. Among the above compounds, acetic acid, citric acid, malic acid, phenylacetic acid and salts thereof are more preferable. The amount of the compound added is preferably 0.2 to 0.6 mol / liter. Examples of the acid include inorganic acids and salts such as sulfuric acid, hydrochloric acid, nitric acid, and boric acid, and organic acids such as formic acid, propionic acid, oxalic acid, and malic acid. Acids and salts such as polycarboxylic acids. Particularly preferred aminocarboxylic acids include β-alanine and piperidine acid. The preferable addition amount of the acid is 0.5 to 40 g / liter. Examples of the chelating agent include aminopolycarboxylic acids such as nitrilotriacetic acid and ethylenediaminetetraacetic acid, and salts thereof. Examples of the surfactant include anionic surfactants such as sulfated products and sulfonated products, nonionic surfactants such as polyethylene glycols and esters, and amphoteric surfactants described in JP-A-57-6840. It is done. Examples of the wetting agent include alkanolamine and alkylene glycol. Examples of the fixing accelerator include thiourea derivatives described in JP-A Nos. 45-35754, 58-122535 and 58-122536, alcohols having a triple bond in the molecule, US Pat. No. 4,126, And the thioether described in No. 459. The pH after the dissolution or dilution of the fixing solution is usually preferably 3.8 or more, more preferably 4.2 to 5.5. The fixing temperature is preferably 20 to 60 ° C, more preferably 30 to 45 ° C.
[0138]
The development time is preferably 3 to 90 seconds, more preferably 5 to 60 seconds, and the fixing time is preferably 3 to 90 seconds, more preferably 5 to 60 seconds. The total processing time including development, fixing, washing and drying is preferably from 15 to 210 seconds, more preferably from 15 to 90 seconds, in Dry to Dry.
[0139]
【Example】
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these.
[0140]
Example 1
<< Preparation of photosensitive silver halide emulsion A >>
After dissolving 7.5 g of inert gelatin and 10 mg of potassium bromide in 900 ml of water and adjusting the temperature to 35 ° C. and pH to 3.0, 370 ml of an aqueous solution containing 74 g of silver nitrate and bromide at a molar ratio of (98/2) 370 ml of an aqueous solution containing potassium and potassium iodide (equal molar amount to the above silver nitrate) and K₂[Ir (NO) Cl_Five] 1 × 10 per mole of silver^-6Mole and rhodium chloride salt at 1 × 10 5 per mole of silver^-FourMole was added by the controlled double jet method while maintaining pAg 7.7. Thereafter, 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene was added, the pH was adjusted to 5 with NaOH, the average particle size was 0.06 μm, the coefficient of variation in projected diameter area was 8%, [100 Cubic silver iodobromide grains having an area ratio of 87% were obtained. This emulsion was coagulated and precipitated using a gelatin flocculant, desalted and then added with 0.1 g of phenoxyethanol to adjust the pH to 5.9 and pAg 7.5 to obtain a silver halide emulsion. This silver halide emulsion is then added to 3 × 10 per mole of silver.^-2Mole hypo was added and reacted at 55 ° C. for 60 minutes for chemical sensitization. Thereafter, after the temperature of the silver halide emulsion was lowered to room temperature, an antifoggant described later was added to prepare a photosensitive silver halide emulsion.
[0141]
According to the method of Example 1 described in JP-A-9-127643, silver behenate was prepared by the following method.
[0142]
<< Preparation of sodium behenate salt solution >>
34 g of behenic acid was dissolved in 340 ml of isopropanol at 65 ° C. Next, a 0.25N aqueous sodium hydroxide solution was added with stirring to pH 8.7. At this time, about 400 ml of sodium hydroxide aqueous solution was required. Next, this aqueous solution of sodium behenate was concentrated under reduced pressure so that the concentration of sodium behenate was 8.9% by weight.
[0143]
<< Preparation of silver behenate >>
A 2.94 M silver nitrate solution was added to a solution of 30 g ossein gelatin dissolved in 750 ml distilled water to adjust the silver potential to 400 mV. Into this, 374 ml of the sodium behenate solution was added at a temperature of 78 ° C. using a controlled double jet method, and at the same time, a 2.94 M aqueous silver nitrate solution was added. The amounts of sodium behenate and silver nitrate used at the time of addition were 0.092 mol and 0.101 mol, respectively.
[0144]
After completion of the addition, the mixture was further stirred for 30 minutes, and water-soluble salts were removed by ultrafiltration.
[0145]
<< Preparation of photosensitive emulsion >>
To the silver behenate dispersion, 0.01 mol of the silver halide emulsion was added, and 100 g of a polyvinyl acetate n-butyl acetate solution (1.2 wt%) was gradually added while stirring to flock the dispersion. After the formation, water was removed, and after further washing with water and removal of water, 60 g of a 1: 2 mixed solution of polyvinyl butyral (average molecular weight 3000) of 2.5 wt% butyl acetate and isopropyl alcohol as a binder was stirred. Then, polyvinyl butyral (average molecular weight 4000) and isopropyl alcohol were added as a binder and dispersed in the gel-like mixture of behenic acid and silver halide thus obtained.
[0146]
The following layers were sequentially formed on a PET support to prepare a sample. In addition, each drying was performed at 75 degreeC for 5 minutes.
[0147]
Back side application: A liquid having the following composition was applied to a wet thickness of 80 μm.
[0148]
150 ml of polyvinyl butyral (10% isopropanol solution)
Dye-B 70mg
Dye-C 70mg
[0149]
[Formula 4]

[0150]
Photosensitive layer side coating
Photosensitive layer 1: The following composition solution was coated with a silver amount of 2.0 g / m.²The amount of polyvinyl butyral as a binder described in Table 1 (g / m²) Was applied.
[0151]
Photosensitive silver halide emulsion A 0.1 g / m as silver amount²Amount to be
Silver behenate 1.9 g / m as silver²Amount to be
Sensitizing dye-1 (0.1% DMF solution) 2 mg
Antifoggant-1 (0.01% methanol solution) 3 ml
Antifoggant-2 (1.5% methanol solution) 8 ml
Antifoggant-3 (2.4% DMF solution) 5 ml
Phthalazone (4.5% DMF solution) 8ml
Thickening agent H (1% methanol / DMF = 4: 1 solution) 2 ml
Reducing agent A-4 (20% methanol solution) 29.5 ml
[0152]
[Chemical formula 5]

[0153]
[Chemical 6]

[0154]
Surface protective layer: A solution having the following composition was applied on each photosensitive layer so as to have a wet thickness of 50 μm.
[0155]
175 ml of acetone
2-propanol 40ml
Methanol 15ml
Cellulose acetate 8.0g
Phthalazine 1.0g
4-methylphthalic acid 0.72g
Tetrachlorophthalic acid 0.22g
Tetrachlorophthalic anhydride 0.5g
1% (W / W) based on monodispersed silica binder with an average particle size of 4 μm
<< Exposure and development process >>
X-ray image information obtained by the aforementioned FPD (a chest phantom image including an early lung cancer mass-like pseudo-shadow) is exposed with a laser scanner, and then at 15 ° C. at 110 ° C. using an automatic processor having a heat drum. Second heat development processing. At that time, exposure and development were performed in a room adjusted to 23 ° C. and 50% RH.
[0156]
The X-ray image of the same phantom and chest X-ray image was input with a Regius 330 manufactured by Konica Corporation, exposed in the same manner, and the ability to detect a mass-like pseudo-shadow was evaluated in five stages.
[0157]
The evaluation described above was performed under the same observation conditions, and expressed as an average value of the evaluation of eight persons.
[0158]
<Evaluation of sharpness>
5 A very good level that clearly shows the difference
4 Slightly superior level with significance
3 Levels that are not particularly problematic in the market
2 Slightly degraded, but no major problems
1 Level where significant deterioration is recognized and there is a major problem
<< Measurement method of dry film thickness >>
A cross section of a sample that was left in an atmosphere of 23 ° C. and 50% RH for at least 2 hours was photographed using an electron microscope, and the dry film thickness of the photosensitive layer was measured.
[0159]
The obtained results are shown in Table 1 below.
[0160]
[Table 1]

[0161]
From the results in Table 1, it can be seen that Samples 2 to 5 using the image recording method of the present invention have significantly improved sharpness by reducing the thickness of the photosensitive layer. On the other hand, it is clear that the sharpness of the sample using the conventional image recording method using the Regius 330 is not improved even if the film thickness of the photosensitive layer is reduced.
[0162]
Example 2
<< Preparation of photosensitive material >>
Silver halide emulsion E1 and silver halide emulsion E2 were prepared as follows.
[0163]
A1
Ossein gelatin 24.2g
9657ml water
S-3 (10% methanol aqueous solution) 6.78 ml
HO- (CH₂CH₂O)_n-(CH (CH_Three) CH₂O)₁₇-(CH₂CH₂O)_mH
n + m≈5.7
Potassium bromide 10.8g
114ml of 10% nitric acid
B1
2.5N silver nitrate aqueous solution 2825ml
C1
841 g of potassium bromide
Finish to 2825 ml with water.
[0164]
D1
1.75N potassium bromide aqueous solution The following silver potential control amount
Using a mixing stirrer shown in Japanese Patent Publication Nos. 58-58288 and 58-58289 at 40 ° C., 464.3 ml of each of solution B1 and solution C1 was added to solution A1 by the simultaneous mixing method over 90 seconds to form nucleation. went.
[0165]
After the addition of the solution B1 and the solution C1 is stopped, the temperature of the solution A1 containing the nucleus is raised to 60 ° C. over 60 minutes, and the pH is adjusted to 5.0 with 3% KOH, and then the solution B1 and the solution C1 are again added. By the simultaneous mixing method, each was added for 42 minutes at a flow rate of 55.4 ml / min. The silver potential (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) during the temperature increase from 42 ° C. to 60 ° C. and the re-simultaneous mixing with the solutions B1 and C1, respectively, using the solution D1 , +14 mV and +25 mV.
[0166]
After the addition was completed, the pH was adjusted to 6 with 3% KOH, and immediately desalted and washed with water to obtain Emulsion E1. In this silver bromide emulsion, 90% or more of the total projected area of silver halide grains is composed of hexagonal tabular grains having a maximum adjacent side ratio of 1.0 to 2.0, and the average thickness of the hexagonal tabular grains is 0.00. It was confirmed with an electron microscope that 08 μm and the average diameter (circular equivalent diameter) were 0.45 μm.
[0167]
Further, the variation coefficient of the thickness was 22%, and the variation coefficient of the distance between twin planes was 33%. The silver bromide emulsion had an average volume particle size of 0.23 μm. The coefficient of variation of the average volume particle size was 15%.
[0168]
Next, after the emulsion was heated to 60 ° C., 10 minutes after the addition of the predetermined amount of spectral sensitizing dye D-1, a mixed aqueous solution of adenine, ammonium thiocyanate, chloroauric acid and sodium thiosulfate and triphenylphosphine Selenide dispersion was added and aged for a total of 90 minutes. At the end of ripening, a predetermined amount of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene was added as a stabilizer.
[0169]
In addition, said additive and its addition amount (per mol of AgX) are shown below.
[0170]

Monodispersion with an average particle size of 0.1 μm by adding potassium bromide aqueous solution and silver nitrate aqueous solution to 0.5% gelatin aqueous solution by double jet method while controlling at 60 ° C., pAg: 8.0, pH: 2.0 A cubic emulsion was obtained. Using this silver bromide as the core, 1 x 10 per mole of silver^-6A monodispersed cubic emulsion (1,000 grains) having an average volume particle size of 0.22 μm by adding a potassium bromide aqueous solution containing a molar amount of potassium hexachloroiridate and an aqueous silver nitrate solution while controlling the pAg to be 7.3. As a result, the (100) plane was 98%, and the particle size variation coefficient was 10%).
[0171]
While maintaining this emulsion at 40 ° C., formaldehyde condensate of sodium naphthalenesulfonate and magnesium sulfate were added, and after stirring and standing, excess salts were removed by decantation. Next, it was redispersed in an appropriate amount of gelatin aqueous solution to obtain Emulsion E2.
[0172]
Next, after the emulsion was heated to 60 ° C., 10 minutes after the addition of the predetermined amount of spectral sensitizing dye D-1, a mixed aqueous solution of adenine, ammonium thiocyanate, chloroauric acid and sodium thiosulfate and triphenylphosphine selena. The id dispersion was added and aged for a total of 70 minutes. At the end of ripening, a predetermined amount of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene was added as a stabilizer.
[0173]
In addition, said additive and its addition amount (per mol of AgX) are shown below.
[0174]

Using the emulsion E3 obtained by mixing the obtained emulsions E1 and E2 at a ratio of E1: E2 = 10: 90, the following samples were prepared.
[0175]
<Preparation of emulsion layer coating solution>
The following various additives were added to the emulsion E3 obtained above.
[0176]

The amount of gelatin was adjusted to the amount shown in Table 2.
[0177]
<< Preparation of coating solution for protective layer >>
Gelatin Amount listed in Table 2

The obtained silver halide photographic light-sensitive material was processed and evaluated using the following developer and fixer.
[0178]
<Developer>

[0179]
[Chemical 7]

[0180]
Add water to 1 liter and adjust to pH 10.0 with potassium hydroxide.
[0181]
The composition of the fixer is shown below.
[0182]
<Fixing solution>
Ammonium thiosulfate 130.0g
Sodium thiosulfate 15.0g
Sodium sulfite 10.0g
Sodium acetate 30.0g
Succinic acid 10.5g
Tartaric acid 2.5g
Aluminum sulfate (octahydrate) 15.0g
D-man knit 15.0g
D-Sorbit 9.0g
Add water to 1 liter and adjust to pH 4.60 with sodium hydroxide.
[0183]
The replenishment amount of the developer and the fixing solution is 50 mmol / m in terms of the replenishment amount of the developer by the developer.²The fixing solution is 150 mmol / m in terms of the replenishment amount of the fixing agent.²Was set.
[0184]
The X-ray image information (chest phantom image including the mass-like pseudo shadow of the initial lung cancer) obtained by the above-mentioned FPD was exposed to each of the samples shown in Table 2 with a laser scanner, and the above-mentioned processing liquid was applied. Using the automatic developing machine TCX-701 manufactured by Konica Corporation, processing was performed for 45 seconds at a development temperature of 35 ° C. and a fixing temperature of 34 ° C.
[0185]
Input X-ray image of chest X-ray image (alignment of exposure dose) of the same patient with Regika 330 (conventional X-ray imaging system using stimulable phosphor plate) manufactured by Konica. Sample No. The films 1 to 5 were exposed in the same manner, and the detectability of ground glass shading was evaluated in five stages. Rank 5 indicates the level that can be detected best, and rank 1 indicates a level that is not known at all.
[0186]
The evaluation described above was performed under the same observation conditions and expressed as an average value of the evaluations of eight people.
[0187]
[Table 2]

[0188]
From the results in Table 2, it can be seen that Samples 2 to 5 using the image recording method of the present invention have significantly improved sharpness by reducing the thickness of the photosensitive layer. On the other hand, it is clear that the sharpness of the sample using the conventional image recording method using the Regius 330 is not improved even if the film thickness of the photosensitive layer is reduced.
[0189]
【The invention's effect】
According to the present invention, in the X-ray image recording method using FPD, the film thickness of the photosensitive layer of the photothermographic material containing photosensitive silver halide, non-photosensitive reducible silver source and reducing agent of the silver source. It was possible to provide an X-ray image recording method that gives an image with excellent sharpness by thinning the film to 1 μm to 10 μm. Also, in the X-ray image recording method using FPD, X-ray image recording gives an image with excellent sharpness by reducing the film thickness of the emulsion layer of the silver halide photographic light-sensitive material to 0.5 μm to 2.0 μm. Could provide a way.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an X-ray image forming system.
FIG. 2 is a schematic cross-sectional view showing an FPD.
FIG. 3 is a schematic plan view showing an FPD.
[Explanation of symbols]
1 X-ray tube
2 FPD
3 Image processing section
4 network
5 CRT display
6 Laser imager

Claims (2)

X-ray image information is captured by a flat panel detector, X-ray image information is taken out from the flat panel detector as an image signal, converted into laser light intensity, photosensitive silver halide, non-photosensitive reducible silver source and In an X-ray image recording method for obtaining an X-ray image by performing a scanning exposure on a photothermographic material containing a reducing agent for the silver source and then performing a heat treatment, the dry film thickness of the photosensitive layer of the photothermographic material Is 1 μm to 10 μm. X-ray image information is captured by a flat panel detector, X-ray image information is taken out from the flat panel detector as an image signal, converted into laser light intensity, scanned and exposed to a silver halide photographic light-sensitive material, and developed. An X-ray image recording method for obtaining an X-ray image, wherein the film thickness of the emulsion layer of the silver halide photographic light-sensitive material is 0.5 μm to 2.0 μm.

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