JP4053749B2 - Silver halide photographic emulsion - Google Patents

Description

【００６０】
また、ホルムアルデヒドガスによる写真性能の劣化を防止するために、米国特許４，４１１，９８７号や同第４，４３５，５０３号に記載されたホルムアルデヒドと反応して、固定化できる化合物を感光材料に添加することが好ましい。
本発明には種々のカラーカプラーを使用することができ、その具体例は前出のリサーチ・ディスクロージャーNo．１７６４３、VII−Ｃ〜Ｇ、および同No．３０７１０５、VII−Ｃ〜Ｇに記載された特許に記載されている。
【００６１】
【実施例】
以下に本発明の実施例を示す。但し本発明は、この実施例に限定されるものではない。
（実施例−１）
エピタキシャル部を有する平板粒子より成る乳剤において、ホスト平板粒子内に環状帯を設けることによる効果、および本発明において主表面平行層を設けることによる効果について説明する。
【００６２】
（乳剤ａの調製）
ＫＢｒ１．２ｇ、平均分子量１５０００の酸化処理ゼラチン１．５ｇを含む水溶液１６００ｍＬを３５℃に保ち撹拌した。ＡｇＮＯ₃（２．７ｇ）水溶液とハロゲン（ＫＢｒ１．９ｇと上記ゼラチン１．２ｇを含有する）水溶液をダブルジェット法で３０秒間に渡り添加した。ＫＢｒ水溶液（ＫＢｒ３．２ｇ）を添加した後、５５℃に昇温した。平均分子量１０００００の酸化処理ゼラチン３０ｇを含む水溶液を添加した後、第一成長としてＡｇＮＯ₃（１７５．３ｇ）水溶液とＫＢｒ水溶液をダブルジェット法で４０分間に渡り流量加速して添加した。この時、銀電位を飽和カロメル電極に対して−２０ｍＶに保った。その後、第二成長としてＡｇＮＯ₃（１６．０ｇ）水溶液とＫＢｒ水溶液をダブルジェット法で９分間に渡り添加した。この時、銀電位を飽和カロメル電極に対して−２０ｍＶに保った。その後平均分子量１０００００の通常ゼラチン１４ｇを含む水溶液を添加した。
【００６３】
次いで４０℃に降温し、第三成長としてＡｇＮＯ₃（９．９ｇ）水溶液とＫＢｒ水溶液をダブルジェット法で９．５分間に渡り添加した。この時ＫＢｒ水溶液の添加を調整し、銀電位が飽和カロメル電極に対して第三成長開始時の−３０ｍＶから第三成長終了時の＋４４ｍＶへ単調に変化していくようにした。以上でエピタキシャル沈着前のホスト平板粒子が完成した。
その後、増感色素Ｉ、II、IIIを７：２：１のモル比で飽和被覆量の８５％の比率で添加した。ヘキサシアノルテニウム（II）酸カリウムを９．９×１０^-5モル（以降ホスト平板粒子の銀量１モルに対して）添加した。ＡｇＮＯ₃（９．６ｇ）水溶液とＫＢｒ（１．６ｇ）とＮａＣｌ（２．９ｇ）とＫＩ（２．０ｇ）を含むハロゲン水溶液を１分間に渡りダブルジェット法で添加することにより、ホスト平板粒子の頂点部に接合するエピタキシャル部を形成した。
【００６４】
かぶり防止剤Ｉを１×１０^-4モル添加した後、乳剤を３５℃で常法に従い水洗し、平均分子量１０００００の脱イオンゼラチンを添加し４０℃で再分散しｐＨを６．５に調整した。
５０℃に昇温し、チオシアン酸カリウム、塩化金酸、チオ硫酸ナトリウムおよびＮ，Ｎ−ジメチルセレノ尿素を添加し最適に化学増感を施した。かぶり防止剤IIを３．２×１０^-4モル添加して化学増感を終了した。この乳剤を乳剤ａとした。
【００６５】
乳剤ａは平均円相当径０．６６μｍ、円相当径の変動係数２２％、平均厚み０．０６６μｍ、厚みの変動係数１８％、平均アスペクト比１０の平板粒子であった。また、全投影面積の９０％以上が最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比が１．４以下である（１１１）面を主表面とする六角形平板粒子で占められていた。粒子の切断断面の電子顕微鏡観察から平均双晶面間隔は０．００８μｍでありその変動係数は１７％であった。低温での透過電子顕微鏡観察の結果、全投影面積の７５％以上がエピタキシャル部に転位線が観測された。この転位線は網目状であった。本乳剤はホスト平板粒子内に、本発明で推奨する環状帯および主表面平行層を持たない。
【００６６】
【化１】

【００６７】
【化２】

【００６８】
（乳剤ｂの調製）
乳剤ａの調製において第二成長を以下のように変更した以外は同様にして乳剤ｂを調製した。
ＡｇＮＯ₃（１５．７ｇ）水溶液とＫＢｒ水溶液をダブルジェット法で１２分間に渡り添加した。後半の６分間については、上記のダブルジェットと並行して、添加直前に調製したＡｇＩ超微粒子乳剤をＫＩ質量換算で０．３３ｇ添加した。ＡｇＩ超微粒子乳剤は米国特許第５，００４，６７９号に記載の方法で調製した。ＡｇＩ超微粒子の平均粒子サイズは９ｎｍで粒子サイズ分布の変動係数は２４％であった。
【００６９】
乳剤ｂは平均円相当径、円相当径の変動係数、平均厚み、厚みの変動係数、平均アスペクト比、最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比、主表面の面指数および平均双晶面間隔が前記の乳剤ａとほぼ同じであった。低温での透過電子顕微鏡観察の結果、全投影面積の８０％以上がエピタキシャル部に転位線が観測された。この転位線は網目状であった。本乳剤はホスト平板粒子の中心から粒子端部までの距離をｄとした場合に、ホスト平板粒子の中心から０．９７ｄ以遠に本発明で推奨する環状帯を持つ。該環状帯の幅は約６ｎｍであり、その沃化銀含量は４モル％であった。
【００７０】
（乳剤ｃの調製）
乳剤ａの調製において第二成長を以下のように変更した以外は同様にして乳剤ｃを調製した。
ＡｇＮＯ₃（１５．４ｇ）水溶液とＫＢｒ水溶液をダブルジェット法で１２分間に渡り添加した。後半の６分間については、上記のダブルジェットと並行して、添加直前に調製したＡｇＩ超微粒子乳剤をＫＩ質量換算で０．６５ｇ添加した。ＡｇＩ超微粒子乳剤は米国特許第５，００４，６７９号に記載の方法で調製した。ＡｇＩ超微粒子の平均粒子サイズは９ｎｍで粒子サイズ分布の変動係数は２４％であった。
【００７１】
乳剤ｃは平均円相当径、円相当径の変動係数、平均厚み、厚みの変動係数、平均アスペクト比、最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比、主表面の面指数および平均双晶面間隔が前記の乳剤ａとほぼ同じであった。低温での透過電子顕微鏡観察の結果、全投影面積の８０％以上がエピタキシャル部に転位線が観測された。この転位線は網目状であった。本乳剤はホスト平板粒子の中心から粒子端部までの距離をｄとした場合に、ホスト平板粒子の中心から０．９７ｄ以遠に本発明で推奨する環状帯を持つ。該環状帯の幅は約６ｎｍであり、その沃化銀含量は８モル％であった。
【００７２】
（乳剤ｄの調製）
乳剤ａの調製において第二成長を以下のように変更した以外は同様にして乳剤ｄを調製した。
ＡｇＮＯ₃（１４．７ｇ）水溶液とＫＢｒ水溶液をダブルジェット法で１２分間に渡り添加した。上記のダブルジェットと並行して、添加直前に調製したＡｇＩ超微粒子乳剤をＫＩ質量換算で１．２５ｇ添加した。 ＡｇＩ超微粒子乳剤は米国特許第５，００４，６７９号に記載の方法で調製した。ＡｇＩ超微粒子の平均粒子サイズは９ｎｍで粒子サイズ分布の変動係数は２４％であった。
【００７３】
乳剤ｄは平均円相当径、円相当径の変動係数、平均厚み、厚みの変動係数、平均アスペクト比、最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比、主表面の面指数および平均双晶面間隔が前記の乳剤ａとほぼ同じであった。低温での透過電子顕微鏡観察の結果、全投影面積の８５％以上がエピタキシャル部に転位線が観測された。この転位線は網目状であった。本乳剤はホスト平板粒子の中心から粒子端部までの距離をｄとした場合に、ホスト平板粒子の中心から０．９５ｄ以遠に本発明で推奨する環状帯を持つ。該環状帯の幅は約１２ｎｍであり、その沃化銀含量は８モル％であった。
【００７４】
（乳剤ｅの調製）
乳剤ｄの調製において第三成長を以下のように変更した以外は同様にして乳剤ｅを調製した。
ＡｇＮＯ₃（９．９ｇ）水溶液、ＫＩ水溶液（Ａｇに対して６モル％）、およびＫＢｒ水溶液をトリプルジェット法で９．５分間に渡り添加した。この時ＫＢｒ水溶液の添加を調整し、銀電位が飽和カロメル電極に対して＋４４ｍＶとなるようにした。
【００７５】
乳剤ｅは平均円相当径、円相当径の変動係数、平均厚み、厚みの変動係数、平均アスペクト比、最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比、主表面の面指数および平均双晶面間隔が前記の乳剤ａとほぼ同じであった。低温での透過電子顕微鏡観察の結果、全投影面積の８５％以上がエピタキシャル部に転位線が観測された。この転位線は網目状であった。本乳剤はホスト平板粒子の中心から粒子端部までの距離をｄとした場合に、ホスト平板粒子の中心から０．９５ｄ以遠に本発明で推奨する環状帯を持つ。該環状帯の幅は約１４ｎｍであり、その沃化銀含量は６〜８モル％の範囲であった。また、本乳剤はホスト平板粒子主表面から深さ２ｎｍ程度の領域に、本発明で推奨する主表面平行層を持つ。該主表面平行層の沃化銀含量は６モル％であり、厚みは約２ｎｍであった。
【００７６】
（乳剤ｆの調製）
乳剤ｅの調製において第三成長後でかつ増感色素添加前に、ＫＩ水溶液をＫＩ質量換算で０．３５ｇ添加した。
乳剤ｆは平均円相当径、円相当径の変動係数、平均厚み、厚みの変動係数、平均アスペクト比、最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比、および平均双晶面間隔が前記の乳剤ａとほぼ同じであった。低温での透過電子顕微鏡観察の結果、全投影面積の８５％以上がエピタキシャル部に転位線が観測された。この転位線は網目状であった。本乳剤はホスト平板粒子の中心から粒子端部までの距離をｄとした場合に、ホスト平板粒子の中心から０．９５ｄ以遠に本発明で推奨する環状帯を持つ。該環状帯の幅は約１４ｎｍであり、その沃化銀含量は６〜８モル％の範囲であった。また、本乳剤はホスト平板粒子主表面から深さ３ｎｍ程度の領域に、本発明で推奨する主表面平行層を持つ。該主表面平行層の沃化銀含量は９〜１３モル％であり、厚みは約３ｎｍであった。
【００７７】
下塗り層を設けてある三酢酸セルロースフィルム支持体に下記表１に示すような塗布条件で上記の化学増感を施した乳剤を保護層を設けて塗布し、試料Ｎｏ．１−１〜６を作成した。
【００７８】
【表１】

【００７９】
これらの試料を４０℃、相対湿度７０％の条件下に１４時間放置した。その後、富士フイルム（株）製ゼラチンフィルターＳＣ−５０と連続ウェッジを通して１／１００秒間露光した。
富士写真フイルム（株）製ネガプロセサーＦＰ−３５０を用い、従来記載の方法でカラ−ネガ処理した。その際、発色現像の処理時間は１分１５秒とした。その後、処理済みの試料を緑色フィルターで濃度測定した。
【００８０】
感度は、かぶりプラス０．２の濃度を与える露光量の逆数を比較することで評価し、試料Ｎｏ．１−１の感度を１００とした場合の相対値を表２に示す。
また、露光量の多いハイライト部の階調については、各試料の特性曲線の濃度２．２の点における曲線の傾きを比較することで評価し、同じく表２に示す。
さらに、圧力を受けた際に生じるカブリについては以下の様に評価した。先ず、各試料を２５℃相対湿度５０％の環境下で、乳剤面を内側にして、角度２０°で５秒間折り曲げた。次いで、発色現像の処理時間を２分４５秒とした条件で現像処理した。こうして得られた試料の、折り曲げ部の圧力カブリの最大濃度を比較した。その結果を表２に示す。
【００８１】
【表２】

【００８２】
表２の結果から明らかなように、エピタキシャル部を有する平板乳剤は、本発明で推奨する環状帯をホスト平板粒子内に設けることにより、高感度で、ハイライト部の階調が硬調となり、圧力カブリ濃度が低下する。環状帯の幅および沃化銀含量を本発明で推奨する範囲にすると、さらに好ましい。それに加えて、本発明で推奨する主表面並行層を設けると、感度が更に上昇することも表２の結果より明らかである。
【００８３】
（実施例−２）
本発明の、エピタキシャル部を有し、かつホスト平板粒子内に環状帯、主表面平行層を有する平板粒子より成る乳剤において、エピタキシャル部に転位線を有することによる効果、およびホスト平板粒子の主表面上に転位線を有することによる効果について説明する。
【００８４】
（乳剤ｇの調製）
ＫＢｒ１．２ｇ、平均分子量１５０００の酸化処理ゼラチン１．５ｇを含む水溶液１６００ｍＬを３５℃に保ち撹拌した。ＡｇＮＯ₃（２．７ｇ）水溶液とハロゲン（ＫＢｒ１．９ｇと上記ゼラチン１．２ｇを含有する）水溶液をダブルジェット法で３０秒間に渡り添加した。ＫＢｒ水溶液（ＫＢｒ３．２ｇ）を添加した後、５５℃に昇温した。平均分子量１０００００の酸化処理ゼラチン３０ｇを含む水溶液を添加した後、第一成長としてＡｇＮＯ₃（１７５．３ｇ）水溶液とＫＢｒ水溶液をダブルジェット法で４０分間に渡り流量加速して添加した。この時、銀電位を飽和カロメル電極に対して−２０ｍＶに保った。その後、第二成長としてＡｇＮＯ₃（１６．０ｇ）水溶液、ＫＩ水溶液（Ａｇに対して８モル％）、およびＫＢｒ水溶液をトリプルジェット法で９分間に渡り添加した。この時、銀電位を飽和カロメル電極に対して−２０ｍＶに保った。その後平均分子量１０００００の通常ゼラチン２０ｇを含む水溶液を添加した。
【００８５】
次いで４０℃に降温し、第三成長としてＡｇＮＯ₃（９．９ｇ）水溶液、ＫＩ水溶液（Ａｇに対して８モル％）、およびＫＢｒ水溶液をトリプルジェット法で９分間に渡り添加した。この時ＫＢｒ水溶液の添加を調整し、銀電位が飽和カロメル電極に対して第三成長開始時の−３０ｍＶから第三成長終了時の＋４４ｍＶへ単調に変化していくようにした。その後、ＫＩ水溶液をＫＩ質量換算で０．３ｇ添加した。
以上でエピタキシャル沈着前のホスト平板粒子が完成した。
【００８６】
その後、増感色素Ｉ、II、IIIを７：２：１のモル比で飽和被覆量の８５％の比率で添加した。ヘキサシアノルテニウム（II）酸カリウムを９．９×１０^-5モル（以降ホスト平板粒子の銀量１モルに対して）添加した。ＡｇＮＯ₃（９．６ｇ）水溶液とＫＢｒ（１．６ｇ）とＮａＣｌ（２．９ｇ）とＫＩ（２．０ｇ）を含むハロゲン水溶液を１分間に渡りダブルジェット法で添加することにより、ホスト平板粒子の頂点部に接合するエピタキシャル部を形成した。
かぶり防止剤IIを４×１０^{- ５}モル添加した後、乳剤を３５℃で常法に従い水洗し、平均分子量１０００００の脱イオンゼラチンを添加し４０℃で再分散しｐＨを６．５に調整した。
５０℃に昇温し、チオシアン酸カリウム、塩化金酸、チオ硫酸ナトリウムおよびＮ，Ｎ−ジメチルセレノ尿素を添加し最適に化学増感を施した。かぶり防止剤IIを３．２×１０^-4モル添加して化学増感を終了した。この乳剤を乳剤ｇとした。
【００８７】
乳剤ｇは平均円相当径０．６６μｍ、円相当径の変動係数２２％、平均厚み０．０６６μｍ、厚みの変動係数１８％、平均アスペクト比１０の平板粒子であった。また、全投影面積の９０％以上が最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比が１．４以下である（１１１）面を主表面とする六角形平板粒子で占められていた。粒子の切断断面の電子顕微鏡観察から平均双晶面間隔は０．００８μｍでありその変動係数は１７％であった。低温での透過電子顕微鏡観察の結果、全投影面積の８０％以上がエピタキシャル部に転位線が観測された。この転位線は網目状であった。ホスト平板粒子主表面上の転位線については、ほぼ全ての粒子において観測されなかった。本乳剤はホスト平板粒子の中心から粒子端部までの距離をｄとした場合に、ホスト平板粒子の中心から０．９５ｄ以遠に本発明で推奨する環状帯を持つ。該環状帯の幅は約１３ｎｍであり、その沃化銀含量は８モル％であった。また、本乳剤はホスト平板粒子主表面から深さ３ｎｍ程度の領域に、本発明で推奨する主表面平行層を持つ。該主表面平行層の沃化銀含量は８〜１５モル％であり、厚みは約３ｎｍであった。
【００８８】
（乳剤ｈの調製）
乳剤ｇの調製において、増感色素およびヘキサシアノルテニウム（II）酸カリウム添加後に行うエピタキシャル部形成の条件を以下のように変更した以外は同様にして乳剤ｈを調製した。
ＡｇＮＯ₃（９．６ｇ）水溶液とＫＢｒ（５．１ｇ）とＮａＣｌ（１．１ｇ）とＫＩ（２．０ｇ）を含むハロゲン水溶液を１分間に渡りダブルジェット法で添加することにより、ホスト平板粒子の頂点部に接合するエピタキシャル部を形成した。
【００８９】
乳剤ｈは平均円相当径、円相当径の変動係数、平均厚み、厚みの変動係数、平均アスペクト比、最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比、主表面の面指数および平均双晶面間隔が前記の乳剤ｇとほぼ同じであった。低温での透過電子顕微鏡観察の結果、ほぼ全ての粒子においてエピタキシャル部に転位線が観測されなかった。ホスト平板粒子主表面上の転位線についても、ほぼ全ての粒子において観測されなかった。なお、ホスト平板粒子内の環状帯および主表面平行層の分布と、これらの領域の沃化銀含量については。前記の乳剤ｇとほぼ同じであった。
【００９０】
（乳剤ｉの調製）
乳剤ｇの調製において、増感色素およびヘキサシアノルテニウム（II）酸カリウム添加後に行うエピタキシャル部形成の条件を以下のように変更した以外は同様にして乳剤ｉを調製した。
ＡｇＮＯ₃（９．６ｇ）水溶液とＮａＣｌ（８．７ｇ）水溶液を０．４分間に渡りダブルジェット法で添加し、次いでＡｇＮＯ₃（６．７ｇ）水溶液とＫＢｒ（３．１ｇ）とＫＩ（１．３ｇ）を含むハロゲン水溶液を０．８分間に渡りダブルジェット法で添加することにより、ホスト平板粒子の頂点部に接合するエピタキシャル部を形成した。
【００９１】
乳剤ｉは平均円相当径、円相当径の変動係数、平均厚み、厚みの変動係数、平均アスペクト比、最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比、主表面の面指数および平均双晶面間隔が前記の乳剤ｇとほぼ同じであった。低温での透過電子顕微鏡観察の結果、ほぼ全ての粒子においてエピタキシャル部に転位線が観測された。転位線は網目状のものと筋状のものが共存していた。ホスト平板粒子主表面上の転位線についても、ほぼ全ての粒子において観測されなかった。なお、ホスト平板粒子内の環状帯および主表面平行層の分布と、これらの領域の沃化銀含量については。前記の乳剤ｇとほぼ同じであった。
【００９２】
（乳剤ｊの調製）
乳剤ｇの調製において、第一成長のＡｇＮＯ₃が１４０ｇ添加された時点で、添加直前に調製したＡｇＩ超微粒子乳剤をＫＩ質量換算で３．０ｇ添加する工程を加えることにより乳剤ｊを調製した。ＡｇＩ超微粒子乳剤の添加は、０．２分間で一気に行った。また、ＡｇＩ超微粒子乳剤は米国特許第５，００４，６７９号に記載の方法で調製した。 ＡｇＩ超微粒子の平均粒子サイズは９ｎｍで粒子サイズ分布の変動係数は２４％であった。
【００９３】
乳剤ｊは平均円相当径０．６０μｍ、円相当径の変動係数２２％、平均厚み０．０８μｍ、厚みの変動係数１９％、平均アスペクト比７．５の平板粒子であった。また、全投影面積の９０％以上が最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比が１．４以下である（１１１）面を主表面とする六角形平板粒子で占められていた。平均双晶面間隔とその変動係数は乳剤ｇと同じであった。低温での透過電子顕微鏡観察の結果、全投影面積の８０％以上がエピタキシャル部に転位線が観測された。この転位線は網目状であった。ホスト平板粒子主表面上の転位線については、全投影面積の８０％以上の平板粒子で観測され、その平均の本数は５〜６本であった。この転位線は筋状であった。本乳剤はホスト平板粒子の中心から粒子端部までの距離をｄとした場合に、ホスト平板粒子の中心から０．７７ｄ以遠に本発明で推奨する環状帯を２つ持つ。１つはホスト平板粒子の中心から０．７７ｄの付近から約１２ｎｍの幅で側面方向に向かって分布し、もう１つはホスト平板粒子の中心から０．９６ｄの付近から約１３ｎｍの幅で側面方向に向かって分布していた。その沃化銀含量は、前者が２２〜３０モル％で、後者が８モル％であった。また、本乳剤はホスト平板粒子主表面から深さ８ｎｍ程度までの領域に、本発明で推奨する主表面平行層を持つ。該主表面平行層の沃化銀含量は８〜２５モル％であり、厚みは約８ｎｍであった。
【００９４】
（乳剤ｋの調製）
乳剤ｇの調製において、第一成長のＡｇＮＯ₃が１４０ｇ添加された時点で、添加直前に調製したＡｇＩ超微粒子乳剤をＫＩ質量換算で６．０ｇ添加する工程を加えることにより乳剤ｋを調製した。 ＡｇＩ超微粒子乳剤の添加は、０．４分間で一気に行った。また、ＡｇＩ超微粒子乳剤は米国特許第５，００４，６７９号に記載の方法で調製した。ＡｇＩ超微粒子の平均粒子サイズは９ｎｍで粒子サイズ分布の変動係数は２４％であった。
【００９５】
乳剤ｋは平均円相当径０．６０μｍ、円相当径の変動係数２２％、平均厚み０．０８μｍ、厚みの変動係数１９％、平均アスペクト比７．５の平板粒子であった。また、全投影面積の９０％以上が最小の長さを有する辺の長さに対する最大の長さを有する辺の長さの比が１．４以下である（１１１）面を主表面とする六角形平板粒子で占められていた。平均双晶面間隔とその変動係数は乳剤ｇと同じであった。低温での透過電子顕微鏡観察の結果、全投影面積の８０％以上がエピタキシャル部に転位線が観測された。この転位線は網目状であった。ホスト平板粒子主表面上の転位線については、全投影面積の８０％以上の平板粒子で観測され、その平均の本数は約１６本であった。この転位線は筋状であった。本乳剤はホスト平板粒子の中心から粒子端部までの距離をｄとした場合に、ホスト平板粒子の中心から０．７７ｄ以遠に本発明で推奨する環状帯を２つ持つ。１つはホスト平板粒子の中心から０．７７ｄの付近から約２０ｎｍの幅で側面方向に向かって分布し、もう１つはホスト平板粒子の中心から０．９６ｄの付近から約１３ｎｍの幅で側面方向に向かって分布していた。その沃化銀含量は、前者が２２〜３０モル％で、後者が８モル％であった。また、本乳剤はホスト平板粒子主表面から深さ８ｎｍ程度までの領域に、本発明で推奨する主表面平行層を持つ。該主表面平行層の沃化銀含量は８〜３０モル％であり、厚みは約８ｎｍであった。
【００９６】
実施例１と同様に塗布して試料Ｎｏ．２−１〜５を作成し、写真特性を評価した結果を表３に示す。
【００９７】
【表３】

【００９８】
表３から明らかなように、本発明の乳剤において、エピタキシャル部に転位線を有する粒子から成る乳剤は、エピタキシャル部に転位線を有しない粒子から成る乳剤に対し、高感度でかつハイライト部の階調が硬調である。また、圧力カブリ濃度もやや低く好ましい。圧力かぶり濃度は、主表面上に転位線を設けることにより更に低減させることが可能であるが、主表面上の転位線の本数が多すぎると感度低下および軟調化する傾向があることも表３の結果から明らかである。
【図面の簡単な説明】
【図１】図１は、本発明の環状帯の例（主表面および側面で粒子表面に露出）を示す模式図である（粒子の中心を通り、主表面に垂直な平面で切ったときの断面図）。
【図２】図２は、本発明の環状帯の例（主表面で粒子表面に露出）を示す模式図である（粒子の中心を通り、主表面に垂直な平面で切ったときの断面図）。
【図３】図３は、本発明の環状帯の例（粒子表面に露出せず埋め込まれた例）を示す模式図である（粒子の中心を通り、主表面に垂直な平面で切ったときの断面図）。
【図４】図４は、本発明の環状帯と沃化銀含量が高い主表面平行層が接合している例を示す模式図である（粒子の中心を通り、主表面に垂直な平面で切ったときの断面図）。
【図５】図５は、本発明のハロゲン化銀乳剤粒子の透過型電子顕微鏡写真（倍率：80,000倍）であり、矢印のエピタキシャル部に筋状の転位線が明確に観察される。
【図６】 図６は、本発明のハロゲン化銀乳剤粒子の透過型電子顕微鏡写真（倍率：80,000倍）であり、矢印のエピタキシャル部に網目状の転位線が明確に観察される。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a silver halide photographic light-sensitive material and a silver halide photographic emulsion used therefor. More specifically, the present invention relates to a silver halide photographic emulsion and a silver halide photographic light-sensitive material having high sensitivity, high contrast and excellent pressure characteristics.
[0002]
[Prior art]
It is generally well known to use tabular silver halide grains (hereinafter referred to as “tabular grains”) in order to obtain a high-sensitivity silver halide photographic light-sensitive material. As a sensitization method of these tabular grains, a sensitization method using an epitaxial junction is disclosed in JP-A-58-108526 and 59-133540. Further, regarding application to tabular grains having a smaller thickness or a larger equivalent circle diameter, JP-A-8-69069, 8-101472, 8-101474, 8-101475, 8-171162, 8-171163, 8-101473, 8 -101476, 9-211762, 9-211763, U.S. Pat.Nos. 5,612,176, 5,614,359, 5,629,144, 5,631,126, Nos. 5,691,127 and 5,726,007. On the other hand, the application to tabular grains having a smaller equivalent circle diameter is disclosed in JP-A-10-221798, 10-268457, and 10-339924. However, the epitaxial sensitization method has a high sensitivity in the shadow portion with a small exposure amount, but has a defect that the gradation of the highlight portion with a large exposure amount becomes soft. The reason is not clearly understood, but it is thought that the latent image formation is dispersed in the highlight portion. In addition, the epitaxial sensitization method has the feature that there is little decrease in sensitivity that occurs when pressure is applied, but it has the disadvantage that fogging that occurs when pressure is applied is large, making it practical for use in general photosensitive materials for photography. Made it difficult.
[0003]
[Problems to be solved by the invention]
The present inventor has considered that the reason why the gradation of the highlight portion becomes soft is that the latent image formation is dispersed in the highlight portion. The intention is to concentrate the latent image formation in the vicinity of the epitaxial part by deliberately having a structure in the tabular grains (hereinafter referred to as “host tabular grains”) that form the basis for epitaxial bonding, and intensive investigations are made. It was. In addition, we considered that latent image formation could be concentrated in the vicinity of the epitaxial part by introducing dislocation lines in the epitaxial part. In addition, in order to reduce the fog that occurs when the pressure is applied, the host tabular grain structure is examined.
[0004]
The present inventor has found that the above problems can be solved by setting the structure of host tabular grains and the preparation conditions at the time of epitaxial bonding to unprecedented structures and conditions.
The present invention seeks to provide means capable of satisfying simultaneously the enhancement of the sensitivity and hardness of tabular grains and the solution of pressure problems.
That is, an object of the present invention is to provide a silver halide photographic emulsion and a photographic light-sensitive material that have high sensitivity, high contrast, and low fog generated when subjected to pressure.
[0005]
[Means for Solving the Problems]
  The above object has been achieved by the following means (1) to (10).
  (1) The variation coefficient of the equivalent circle diameter of all particles is 30% or less, and 70% or more of the total projected area is the following (i), (ii),(Iii)as well as( iv )A silver halide photographic emulsion characterized in that it is occupied by an epitaxially bonded silver halide tabular grain that satisfies the above requirements.
(I) Silver iodochlorobromide grains having a (111) plane as the main surface.
(Ii) It has an epitaxial portion at at least one apex of the host tabular grain.
(Iii) When the distance from the center of the host tabular grain to the edge of the grain is d, an annular band having a silver iodide content of 4 mol% or more in a region 0.7 d or more from the centerAnd a region adjacent to the inner side of the annular band in the lateral direction, wherein the silver iodide content is lower by 0.5 mol% or more than the silver iodide content of the annular band.
( iv ) Within a depth of 10 nm from the main surface, there is a main surface parallel layer parallel to the main surface and having a silver iodide content of 4 mol% or more.
[0006]
(2) The silver halide photographic emulsion as described in (1) above, wherein the width of the annular band in (iii) is 10 nm or more.
[0007]
(3) The silver halide photographic emulsion as described in (1) above, wherein the silver iodide content of the annular band in the above (iii) is 7 mol% or more.
[0009]
  (4)  The main surface parallel layer has a thickness of 10% or less of the thickness of the host tabular grain.Any one of (1) to (3)The silver halide photographic emulsion described in 1.
[0010]
  (5)  The silver halide grains occupying 70% or more of the total projected area further satisfy the requirement (v) (1) to(4)The silver halide photographic emulsion according to any one of the above.
(V) The epitaxial portion has at least one dislocation line.
[0011]
  (6)  The variation coefficient of the equivalent circle diameter of all particles is 30% or less, and 70% or more of the total projected area is the following (i), (ii), (iii), ( iv )as well asA silver halide photographic emulsion characterized by being occupied by epitaxially bonded silver halide tabular grains satisfying the requirement (vi).
(I) Silver iodochlorobromide grains having a (111) plane as the main surface.
(Ii) It has an epitaxial portion at at least one apex of the host tabular grain.
(Iii) When the distance from the center of the host tabular grain to the edge of the grain is d, an annular band having a silver iodide content of 4 mol% or more in a region 0.7 d or more from the centerAnd a region adjacent to the inner side of the annular band in the lateral direction, wherein the silver iodide content is lower by 0.5 mol% or more than the silver iodide content of the annular band.
( iv ) Within a depth of 10 nm from the main surface, there is a main surface parallel layer parallel to the main surface and having a silver iodide content of 4 mol% or more.
(Vi) It has at least one dislocation line on the main surface.
[0013]
  (7)  Silver halide grains occupying 70% or more of the total projected area further satisfy the requirement (v)(6)The silver halide photographic emulsion described in 1.
(V) The epitaxial portion has at least one dislocation line.
[0014]
  (8)  (1) or(7)A silver halide photographic light-sensitive material characterized in that the silver halide photographic emulsion is contained in a light-sensitive emulsion layer.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
The silver halide photographic emulsion of the present invention will be described below.
In the present invention, a tabular grain means a silver halide grain having two opposing parallel (111) main surfaces. The tabular grains used in the present invention have one twin plane or two or more parallel twin planes. The twin plane means the (111) plane when ions at all lattice points are mirror images on both sides of the (111) plane.
[0016]
The emulsion according to the present invention has a hexagonal main surface in which the ratio of the length of the side having the maximum length to the length of the side having the minimum length of 70% or more of the projected area of all grains is 2 to 1 It is preferable that the tabular grain has. More preferably, 90% or more of the projected area of all grains has a hexagonal main surface in which the ratio of the length of the side having the maximum length to the length of the side having the minimum length is 2 to 1. Tabular grains. More preferably, 90% or more of the total projected area has a hexagonal main surface in which the ratio of the length of the side having the maximum length to the length of the side having the minimum length is 1.5 to 1 Tabular grains. When the shape of the main surface of the tabular grain is a rounded triangle or hexagon, the length of the sides of the main surface is the length of the sides of the imaginary triangle or hexagon formed by extending each side. Say it.
[0017]
The emulsion of the present invention is preferably monodispersed. The variation coefficient of the equivalent circle diameter of the projected area of all silver halide grains used in the present invention is 30% or less, preferably 25% or less, more preferably 20% or less. Here, the variation coefficient of the equivalent circle diameter is a value obtained by dividing the standard deviation of the distribution of the equivalent circle diameter of each silver halide grain by the average equivalent circle diameter.
[0018]
The equivalent-circle diameter of the tabular grains is obtained, for example, by taking a transmission electron micrograph by a replica method and obtaining the diameter of a circle having an area equal to the projected area of each grain (equivalent circle diameter). The thickness cannot be calculated simply from the length of the shadow of the replica due to epitaxial deposition. However, it can be calculated by measuring the shadow length of the replica of the host tabular grain before epitaxial deposition. Alternatively, even after epitaxial deposition, the sample coated with tabular grains can be cut and easily taken by taking an electron micrograph of the cross section. The grain size of the emulsion of the present invention is not particularly limited, but 70% or more of the total projected area is preferably an aspect ratio of 7 or more, more preferably 10 or more. The equivalent circle diameter is preferably 0.2 μm or more and 8 μm or less, and more preferably 0.3 μm or more and 5 μm or less. The particle thickness is preferably 0.02 μm or more and 0.3 μm or less, more preferably 0.03 μm or more and 0.2 μm or less, and particularly preferably 0.05 μm or more and 0.15 μm or less.
[0019]
The epitaxially bonded tabular grains used in the present invention are silver iodochlorobromide. Preferably, the host tabular grains are silver iodobromide or silver iodochlorobromide, and the epitaxial portion is a combination of silver iodochlorobromide. The silver chloride content of the epitaxially bonded tabular grains of the present invention is preferably 0.5 mol% or more and 6 mol% or less. The silver iodide content of the epitaxially bonded tabular grains of the present invention is preferably 0.2 mol% or more and 10 mol% or less. More preferably, the silver iodide content is 0.4 mol% or more and 5 mol% or less.
[0020]
First, the epitaxial part of the epitaxial emulsion of the present invention will be described in detail.
In the present invention, when the average silver chloride content of the epitaxial part is CL mol%, 70% or more of the total projected area is within the range of 0.7 to 1.3 CL of the silver chloride content of the epitaxial part. It is preferable that it is in the range of 0.8 to 1.2 CL. Further, when the average silver iodide content in the epitaxial part is I mol%, 70% or more of the total projected area is within the range of 0.7 to 1.3 I in the epitaxial part. Preferably, it is in the range of 0.8 to 1.2I. Here, the average silver chloride content and the average silver iodide content in the epitaxial part are the average values of the silver chloride or silver iodide content in the epitaxial part including within and between grains.
[0021]
The intra-particle and inter-particle Cl and I distribution in the epitaxial portion can be analyzed by the following method. Tabular grains in the silver halide photographic light-sensitive material are taken out by treating the light-sensitive material with a proteolytic enzyme and centrifuging it. The particles are re-dispersed and placed on a copper mesh with a support film. In order to prevent the deterioration of the particles, the amount of proteolytic enzyme used is preferably as small as possible. In some cases, a method may be used in which the photosensitive material is cut into layers using a microtome, and the particles together with the binder are taken out. The particles taken out in this way are observed from the main surface direction, and the epitaxial region projected out from the extension of the hexagonal side is scanned with a beam focused to a spot diameter = 2 nm or less with an analytical electron microscope, The silver chloride content and silver iodide content of one epitaxial part are measured. In order to determine the intra-particle and inter-particle distribution, usually 50 or more, preferably 100 or more epitaxial portions are measured. The silver chloride content and the silver iodide content can be calculated by treating silver halide grains having a known content in the same manner as a calibration curve and obtaining the ratio between the Ag intensity and the halogen intensity in advance.
[0022]
A field emission type electron gun with a higher electron density is more suitable as an electron gun for an analytical electron microscope than a thermionic type electron gun, and it is easy to analyze the silver chloride content and silver iodide content of the epitaxial part. it can. At this time, the measurement is preferably performed by cooling to a low temperature in order to prevent the sample from being damaged by the electron beam.
[0023]
The emulsion of the present invention is a tabular grain in which 70% or more of the total projected area has an epitaxial portion at at least one vertex of the principal surface. More preferably, 90% or more of the total projected area is tabular grains having an epitaxial portion at at least one vertex of the principal surface. Here, the apex portion means a portion in a circle having a radius of 1/3 of the length of the shorter side of the two sides adjacent to the apex when the tabular grain is viewed in the vertical direction from the main surface. In the case of a hexagonal shape in which the vertices of the hexagonal tabular grains are rounded, it can be determined whether or not the above requirement is satisfied for a virtual hexagonal shape formed by extending each side. The epitaxial emulsion of the present invention comprises tabular grains having at least one epitaxial portion at the apex. The number of epitaxial portions is preferably six, one for each of the six apexes. In addition to the apex portion of the tabular grain, an epitaxial portion may be formed on the main surface of the tabular grain or on a side other than the apex portion. The judgment of the epitaxial emulsion of the present invention can be made as follows. 100 or more particles are arbitrarily extracted from an electron micrograph of a tabular grain replica, particles having an epitaxial portion at at least one apex, grains having an epitaxial portion only on the side or main surface excluding the apex, and epitaxial Classify into three classes of particles with no part. In the epitaxial emulsion of the present invention, grains having at least one epitaxial portion at the apex thereof are 70% or more of the total projected area, preferably 90% or more of the total projected area.
[0024]
The epitaxial part is silver iodochlorobromide. Preferably, the silver chloride content of the epitaxial part is 5 mol% or more and 80 mol% or less. More preferably, the silver chloride content of the epitaxial part is 10 mol% or more and 65 mol% or less. The silver iodide content in the epitaxial part is preferably 1 mol% or more and 40 mol% or less, more preferably 3 mol% or more and 30 mol% or less.
[0025]
The amount of silver in the epitaxial part is preferably 0.5 mol% or more and 15 mol% or less, and more preferably 1 mol% or more and 9 mol% or less of the silver amount of the host tabular grains. If the amount is too small, an epitaxial emulsion cannot be prepared.
[0026]
The emulsion of the present invention is preferably composed of tabular grains having 70% or more of the total projected area having at least one dislocation line in the epitaxial portion. More preferably, 80% or more of the total projected area is composed of tabular grains having at least one dislocation line in the epitaxial portion. The form of dislocation lines may be a streak shape as shown in FIG. 5 or a mesh shape as shown in FIG. Here, the network-like dislocation line is a dislocation line in which a plurality of dislocation lines that cannot be counted as a number are interlaced like a mesh. In a tabular grain having an epitaxial portion at two or more apex portions, dislocation lines do not necessarily have to exist in each epitaxial portion. It is only necessary that one dislocation line is included in the epitaxial portion joined to at least one apex portion. In the transmission electron micrographs of the silver halide grains shown in FIGS. 5 and 6, the large stripe pattern on the main surface is a moire image produced by the interference of electron beams refracted on the upper and lower main surfaces of the tabular grain. And not dislocation lines.
[0027]
In the emulsion of the present invention, preferably 70% or more of the total projected area, more preferably 80% or more of the total projected area is not epitaxially joined in a terrace shape on the main surface of the apex of the host tabular grain. It consists of tabular grains that project in the lateral direction and epitaxially join. Discrimination between tabular grains that protrude from the top of the main surface in the lateral direction of the host tabular grains and epitaxially join and tabular grains that epitaxially join in a terrace shape on the main surface of the apex of the host tabular grains is performed as follows. . 100 grains or more are arbitrarily extracted from the replica method electron micrograph of tabular grains, and grains having an area of 60% or more of the portion projected in the side direction not overlapping the apex of the total projected area of the epitaxial portion per grain Defined as tabular grains that protrude in the lateral direction of the host tabular grains and epitaxially join. If control is not performed to maintain this shape after epitaxial deposition, dislocation lines disappear due to rearrangement of epitaxial deposition.
[0028]
Next, the host tabular grains of the epitaxial emulsion of the present invention will be described in detail. As for the distribution of silver iodide in the grain of the host tabular grain of the present invention, a multiple structure grain having a double structure or more is preferred. Here, having a structure with respect to the distribution of silver iodide means that the silver iodide content differs between each structure by 0.5 mol% or more, more preferably by 1 mol% or more.
[0029]
The structure regarding the silver iodide distribution can be basically obtained by calculation from the prescription value in the grain preparation process. At the interface between the structures, the change in the silver iodide content can change suddenly or slowly. For these confirmations, it is necessary to consider the measurement accuracy in analysis, but the above-described method using a field emission type analytical electron microscope is effective. The silver iodide distribution in the grains when the tabular grains are viewed from the direction perpendicular to the main surface can be analyzed by the same method. However, the cross section of the tabular grains can be obtained by solidifying the specimen and using a sample cut into ultrathin sections by a microtome. The intragranular silver iodide distribution can also be analyzed.
[0030]
  The host tabular grain of the present invention has an annular band having a silver iodide content of 4 mol% or more in a region 0.7 d or more from the center, where d is the distance from the center of the tabular grain to the grain edge. . The annular band refers to a region having a silver iodide content of 4 mol% or more surrounding the center of a tabular grain in an annular shape. The area adjacent to the inner side of the annular band in the lateral direction has a silver iodide content higher than that of the annular band.0.5 mol% or moreLow. The annular band may be exposed on at least one particle surface of the main surface and the side surface (for example, as shown in FIGS. 1 and 2), or may be embedded in the particle as shown in FIG. . Further, a layer having a high silver iodide content parallel to the main surface may be bonded to the annular band as shown in FIG. The position of the annular band may be a region that is 0.7 d or more away from the center of the host tabular grain, but is preferably located in a region that is 0.85 d or more, and preferably in a region that is 0.95 d or more. Is more preferable. Here, the center of the host tabular grain refers to an axis that passes through the center of gravity of the host tabular grain and penetrates the two main surfaces substantially perpendicularly. The above-mentioned annular band exists in a region 0.7 d or more away from the center of the host tabular grain. More than 75% of the total volume of one annular band exists in a region 0.7 d or more away from the center of the host tabular grain. Refers to what you are doing.
[0031]
The annular band preferably has a width of 10 nm or more in the side surface direction (lateral direction) of the host tabular grain. The upper limit of the width in the lateral direction depends on the size of the host tabular grains, and is preferably 10% or less of the equivalent-circle diameter of the projected area.
[0032]
Further, the silver iodide content of the annular band may be 4 mol% or more, but is preferably 7 mol% or more. The upper limit of the silver iodide content of the annular band is not particularly limited, but is preferably 40 mol% or less.
[0033]
The annular band may be one or plural. In addition, a region having a high silver iodide content may exist in a region closer to the center of the host tabular grain than the annular band (excluding a region adjacent to the annular band). In the host tabular grains of the present invention, the silver iodide content is preferably maximized in the annular band, but this is not necessarily the case.
[0034]
In the emulsion of the present invention, a main surface parallel layer parallel to the main surface and having a silver iodide content of 4 mol% or more is preferably provided in the vicinity of the main surface of each of the host tabular grains. The main surface parallel layer is preferably present within a depth of 10 nm from the main surface. Here, the fact that the main surface parallel layer exists within a depth of 10 nm from the main surface indicates that the portion closest to the main surface of the main surface parallel layer is within a distance of 10 nm from the main surface. A more preferable aspect is that the main surface parallel layer is exposed on the main surface. The main surface parallel layer preferably extends over a region occupying the same area as the main surface when viewed from the direction perpendicular to the main surface, but extends over a narrower range than the main surface when viewed from the center of the tabular grain. Also good.
[0035]
The silver iodide content of the main surface parallel layer may be 4 mol% or more, but is preferably 7 mol% or more, more preferably 14 mol% or more. The upper limit of the silver iodide content of the main surface parallel layer is not particularly limited, but is preferably 40 mol% or less.
The thickness of the main surface parallel layer is preferably 10% or less of the thickness of the host tabular grain.
If the formation conditions of the annular band and the main surface parallel layer recommended in the present invention are deviated, the form of the epitaxial portion tends to be nonuniform within and between the grains. Correlating with this, the photographic performance deteriorates.
[0036]
In the present invention, preferably, when the average silver chloride content of all silver halide grains is CL mol%, 70% or more of the total projected area is within the range of silver chloride content of 0.7 CL to 1.3 CL. And particularly preferably in the range of 0.8 CL to 1.2 CL. In the emulsion of the present invention, since the epitaxial deposition is uniform between grains, the silver chloride content distribution between grains is basically monodisperse. More preferably, when the average silver iodide content of all silver halide grains is I mol%, 70% or more of the total projected area is within the range of 0.7I to 1.3I. Particularly preferably in the range of 0.8I to 1.2I. Since the silver iodide content distribution between grains is monodispersed, epitaxial deposition becomes uniform between grains. The EPMA method (Electron Probe Micro Analyzer method) is usually effective for measuring the silver chloride and silver iodide content of each grain. By preparing a sample in which emulsion grains are dispersed so as not to contact each other and analyzing the X-rays emitted by emitting an electron beam, it is possible to perform elemental analysis of a very small region irradiated with the electron beam. . At this time, the measurement is preferably performed by cooling to a low temperature in order to prevent the sample from being damaged by the electron beam.
[0037]
In the epitaxial emulsion of the present invention, it is possible to reduce fog generated when pressure is applied by providing dislocation lines on the main surface of the host tabular grain. Preferably, in the tabular grain of the present invention having an epitaxial portion of 70% or more of the total projected area, it is preferable to have at least one dislocation line on the main surface.
[0038]
However, the number of dislocation lines on the main surface is preferably about several to 10 per particle. The reason is that the dislocation lines provide preferential deposition positions for epitaxial deposition, which is an obstacle to the formation of epitaxial portions at the apex of host tabular grains intended by the present invention, and has a side effect of lowering sensitivity. .
[0039]
The dislocation lines in the epitaxial part and the dislocation lines on the main surface of the host tabular grain are described in, for example, J.A. F. Hamilton, Photo. Sci. Eng. 11, 57, (1967) and T.W. Shiozawa, J. et al. Soc. Photo. Sci. It can be observed by a direct method using a transmission electron microscope at a low temperature described in Japan, 35, 213, (1972). In other words, the silver halide grains taken out carefully so as not to apply a pressure that causes dislocation lines to the grains from the emulsion are placed on a mesh for electron microscope observation to prevent damage (printout, etc.) due to electron beams. Observation is performed by a transmission method in a state where the tube is cooled. At this time, the thicker the particle, the more difficult it is to transmit the electron beam. Therefore, it is possible to observe more clearly using a high-pressure type electron microscope (200 kV or more for a particle having a thickness of 0.25 μm). . From the photograph of the particles obtained by such a method, the position and number of dislocation lines for each particle when viewed from the direction perpendicular to the main surface can be obtained.
[0040]
Hereinafter, a specific method for preparing the above-described epitaxial emulsion of the present invention will be described in detail by dividing it into two methods: host tabular grain preparation and epitaxial part preparation.
First, the preparation of the host tabular grains basically comprises a combination of three steps of nucleation, ripening and growth.
In the nucleation step, gelatin having a low methionine content described in US Pat. Nos. 4,713,320 and 4,942,120 is used, and a high pBr described in US Pat. No. 4,914,014 is used. The nucleation in a short time as described in JP-A-2-222940 is extremely effective in the nucleation step of the particles used in the present invention. In the present invention, the silver nitrate aqueous solution, the halogen aqueous solution and the low molecular weight oxidized gelatin are preferably added within one minute while stirring in the presence of low molecular weight oxidized gelatin at a temperature of 20 ° C. to 40 ° C. At this time, the pBr of the system is preferably 2 or more, and the pH is preferably 7 or less. The concentration of the aqueous silver nitrate solution is preferably 0.6 mol / liter or less.
[0041]
In the ripening step, the tabular grain emulsion of the present invention is carried out in the presence of a low concentration base described in US Pat. No. 5,254,453 and at a high pH described in US Pat. No. 5,013,641. It can be used in the aging step. U.S. Pat. Nos. 5,147,771, 5,147,772, 5,147,773, 5,171,659, 5,210,013, and It is possible to add the polyalkylene oxide compound described in No. 252,453 in the aging step or the subsequent growth step. In the present invention, the aging step is preferably performed at a temperature of 60 ° C. or higher and 80 ° C. or lower. It is preferable to reduce pBr to 2 or less immediately after nucleation or during aging. Further, additional gelatin is preferably added immediately after nucleation until the end of ripening. Particularly preferred gelatin has 95% or more of amino groups modified to succination or trimellitation.
[0042]
In the growth step of the present invention, it is preferable to simultaneously add the silver nitrate aqueous solution, the halogen aqueous solution containing bromide and the silver iodide fine grain emulsion described in US Pat. Nos. 4,672,027 and 4,693,964. It is done. The silver iodide fine grain emulsion may be substantially silver iodide, and may contain silver bromide and / or silver chloride as long as it can form a mixed crystal. Particularly preferably, the growth step is performed by adding the silver iodobromide fine grain emulsion prepared immediately before. At this time, in order to keep the pAg constant, it is preferable to simultaneously add a halogen aqueous solution, particularly a bromide aqueous solution.
[0043]
Next, the epitaxial part forming step will be described in detail. Epitaxial deposition may be performed immediately after the formation of the host tabular grains, or may be performed after ordinary desalting is performed after the formation of the host tabular grains. In the epitaxial emulsion of the present invention, it is preferably performed immediately after the formation of the host tabular grains.
For the formation of the epitaxial portion immediately after the formation of the host tabular grains, the pH, pAg, gelatin type, concentration and viscosity are selected. The gelatin concentration is important and is preferably 50 g or less per liter. Particularly preferably, it is 5 g or more and 40 g or less. When the amount is too small, epitaxial deposition occurs on the main surface of the tabular grain. When the amount is too large, the epitaxial deposition becomes uneven among the grains due to an increase in viscosity.
[0044]
A sensitizing dye is used as a site indicator for epitaxial bonding of the present invention. By selecting the amount and type of the dye to be used, the epitaxial deposition position can be controlled. The dye is preferably added in an amount of 50% to 90% of the saturated coverage. The dyes used include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes and hemioxonol dyes. Particularly useful dyes are those belonging to the cyanine dye. Any of nuclei usually used for cyanine dyes as basic heterocyclic nuclei can be applied to these dyes. That is, for example, pyrroline nucleus, oxazoline nucleus, thiozoline nucleus, pyrrole nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus, imidazole nucleus, tetrazole nucleus, pyridine nucleus; a nucleus in which an alicyclic hydrocarbon ring is fused to these nuclei; and Nuclei in which aromatic hydrocarbon rings are fused to these nuclei, for example, indolenine nucleus, benzoindolenine nucleus, indole nucleus, benzoxador nucleus, naphthoxazole nucleus, benzothiazole nucleus, naphthothiazole nucleus, benzoselenazole Nuclei, benzimidazole nuclei and quinoline nuclei are applicable. These nuclei may have a substituent on the carbon atom.
[0045]
These sensitizing dyes may be used alone or in combination. The combination of sensitizing dyes is often used for the purpose of supersensitization. Typical examples thereof are U.S. Pat. Nos. 2,688,545, 2,977,229, 3,397,060, 3,522,052, 3,527,641, 3,617,293, 3,628,964, 3,666,480, 3,672,898, 3,679,428, 3,703 377, 3,769,301, 3,814,609, 3,837,862, 4,026,707, British Patent 1,344,281, No. 1,507,803, Japanese Patent Publication Nos. 43-4936, 53-12375, Japanese Patent Application Laid-Open Nos. 52-110618, and 52-109925.
Along with the sensitizing dye, a dye that itself does not have spectral sensitizing action or a substance that does not substantially absorb visible light and exhibits supersensitization may be added simultaneously or separately.
[0046]
When the sensitizing dye is adsorbed, it is preferable for the preparation of an epitaxial emulsion that the silver iodide content of the outermost surface layer of the host tabular grain is set higher than that of the outermost layer. Prior to the addition of the sensitizing dye, iodine ions are added. In the present invention, it is also preferable to add a silver iodide fine grain emulsion to increase the silver iodide content on the surface of the host tabular grain. As a result, the distribution of the silver iodide content between the grains becomes uniform, and the adsorption of the sensitizing dye becomes uniform. As the silver iodide ultrafine grain emulsion, those formed just before the addition described in US Pat. No. 5,004,679 are preferably used. Here, preparing immediately before the addition means that the time from preparation to addition is within 10 minutes. Preferably it is within 1 minute. The addition amount of these iodine ions or silver iodide is 1 × 10 5 per mol of silver in the host tabular grains.^-FourTo 1 × 10^-2The molar range is preferably 1 × 10^-3To 5 × 10^-3A molar range is particularly preferred.
[0047]
The epitaxial part is formed by a solution containing halogen ions and AgNO._ThreeMay be added simultaneously or separately, and may be combined appropriately with the addition of silver chloride fine particles, silver bromide fine particles, silver iodide fine particles having a smaller particle diameter than the host tabular grains, or the addition of mixed crystal grains thereof. And may be added. In particular, in order to make the silver iodide distribution uniform between the epitaxial portions, an iodide is added using a silver iodide ultrafine grain emulsion prepared by the method described in the aforementioned US Pat. No. 5,004,679. Is preferably used. AgNO_ThreeWhen adding the solution, the addition time is preferably 30 seconds or more and 10 minutes or less, and particularly preferably 1 minute or more and 5 minutes or less. In order to form the epitaxial emulsion of the present invention, the concentration of the silver nitrate solution added is preferably 1.5 mol / liter or less, particularly preferably 0.5 mol / liter or less. At this time, it is necessary to efficiently stir the system, and it is preferable that the viscosity of the system is low.
[0048]
The pBr at the time of forming the epitaxial portion is preferably 2.5 or more, particularly preferably 3.2 or more. The temperature is preferably 35 ° C. or higher and 45 ° C. or lower. It is preferable that a 6-cyano metal complex is doped when the epitaxial portion is formed.
[0049]
Among the 6 cyano metal complexes, those containing iron, ruthenium, osmium, cobalt, rhodium, iridium or chromium are preferred. The amount of metal complex added is 10 per mole of silver halide in the finished grain.^-910^-2Preferably in the molar range, 10 per mole of silver halide.^-810^-FourMore preferably, it is in the molar range.
The emulsion of the present invention is preferably added with the above-described sensitizing dye and / or antifoggant and / or stabilizer described later after epitaxial deposition.
[0050]
In the present invention, it is preferable to perform water washing after this. The temperature for washing with water can be selected according to the purpose, but is preferably selected within the range of 5 ° C to 50 ° C. The pH at the time of washing with water can be selected according to the purpose, but is preferably selected between 2 and 10. More preferably, it is the range of 3-8. Although pAg at the time of water washing can also be selected according to the objective, it is preferable to select between 5-10. The washing method can be selected from a noodle washing method, a dialysis method using a semipermeable membrane, a centrifugal separation method, a coagulation sedimentation method, and an ion exchange method. In the case of the coagulation sedimentation method, a method using a sulfate, a method using an organic solvent, a method using a water-soluble polymer, a method using a gelatin derivative and the like can be selected.
[0051]
As the protective colloid to be subsequently dispersed, it is advantageous to use gelatin.
Most preferred is high molecular weight gelatin obtained by crosslinking ordinary gelatin by a chemical method. By using the gelatin, the epitaxial emulsion of the present invention becomes more stable. On the other hand, other hydrophilic colloids can also be used.
For example, gelatin derivatives, graft polymers of gelatin and other polymers, proteins such as albumin and casein; cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose and cellulose sulfates, sugar derivatives such as sodium alginate and starch derivatives Various synthetic hydrophilic polymers such as polyvinyl alcohol, polyvinyl alcohol partial acetal, poly-N-vinyl pyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinyl imidazole, polyvinylpyrazole, or a single or copolymer Substances can be used. Examples of gelatin include lime-processed gelatin, acid-processed gelatin, and Bull. Soc. Sci. Photo. Japan. No. 16. An enzyme-treated gelatin as described in P30 (1966) may be used, and a hydrolyzate or enzyme-decomposed product of gelatin can also be used.
[0052]
The emulsion of the present invention is preferably subjected to chemical sensitization after washing and dispersion. One chemical sensitization that can be preferably carried out in the present invention is chalcogen sensitization and noble metal sensitization, either alone or in combination, by TH James, The Photographic Process, 4th Edition, Macmillan. 1977, (TH James, The Theory of the Photographic Process, 4th ed, Macmillan, 1977), pages 67-76, and can also be performed using active gelatin. Disclosure, 120, April 1974, 12008; Research Disclosure, 34, June 1975, 13452, U.S. Pat. Nos. 2,642,361, 3,297,446, 3, No. 772,031, No. 3,857,711, No. 3,90 714, 4,266,018, and 3,904,415, and British Patent 1,315,755, pAg 5-10, pH 5-8 and temperature 30-30. At 80 ° C., sulfur, selenium, tellurium, gold, platinum, palladium, iridium or a combination of these sensitizers can be used. In the noble metal sensitization, noble metal salts such as gold, platinum, palladium, iridium and the like can be used, and gold sensitization, palladium sensitization and the combined use of both are particularly preferable. In the case of gold sensitization, known compounds such as chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, and gold selenide can be used. The palladium compound means a palladium divalent salt or a tetravalent salt. Preferred palladium compounds are R₂PdX₆Or R₂PdX_FourIt is represented by Here, R represents a hydrogen atom, an alkali metal atom or an ammonium group. X represents a halogen atom and represents a chlorine, bromine or iodine atom.
[0053]
The photographic emulsion used in the present invention may contain various compounds for the purpose of preventing fogging during the production process, storage or photographic processing of the light-sensitive material, or stabilizing the photographic performance. That is, thiazoles such as benzothiazolium salts, nitroimidazoles, nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, amino Triazoles, benzotriazoles, nitrobenzotriazoles, mercaptotetrazoles (especially 1-phenyl-5-mercaptotetrazole); mercaptopyrimidines; mercaptotriazines; for example, thioketo compounds such as oxadrine thione; azaindenes such as , Triazaindenes, tetraazaindenes (especially 4-hydroxy substituted (1,3,3a, 7) chitraazaindenes), pentaazaindene Known as antifoggants or stabilizers, such as, it can be added to many compounds. For example, those described in US Pat. Nos. 3,954,474, 3,982,947, and Japanese Patent Publication No. 52-28660 can be used. One preferred compound is a compound described in JP-A-63-212932. Antifoggants and stabilizers are used before particle formation, during particle formation, after particle formation, during epitaxial formation, in the water washing step, during dispersion after water washing, before chemical sensitization, during chemical sensitization, after chemical sensitization, and before coating. It can be added according to the purpose at various times. In addition to the original antifogging and stabilizing effect added during emulsion preparation, control the crystal wall of grains, reduce grain size, reduce grain solubility, control chemical sensitization, It can be used for various purposes such as controlling the arrangement of dyes.
[0054]
It is preferred to subject the silver halide photographic emulsion of the present invention to reduction sensitization during grain formation, after grain formation and before chemical sensitization, during chemical sensitization, or after chemical sensitization.
Here, reduction sensitization means a method of adding a reduction sensitizer to a silver halide emulsion, a method of growing or ripening in a low pAg atmosphere called pAg 1-7 called silver ripening, and a pH of 8 called high pH ripening. Either a method of growing or aging in an atmosphere having a high pH of ˜11 can be selected. Two or more methods can be used in combination.
[0055]
It is preferable to use an oxidizing agent for silver during the production process of the emulsion of the present invention. The oxidizing agent for silver refers to a compound having an action of acting on metallic silver and converting it into silver ions. Particularly effective are compounds capable of converting extremely fine silver grains by-produced in the process of forming silver halide grains and chemical sensitization into silver ions. The silver ions generated here may form, for example, a silver salt that is hardly soluble in water such as silver halide, silver sulfide, or silver selenide, or a silver salt that is easily soluble in water such as silver nitrate. May be formed. The oxidizing agent for silver may be an inorganic substance or an organic substance. Examples of the inorganic oxidizing agent include ozone, hydrogen peroxide and adducts thereof (for example, NaBO).₂・ H₂O₂・ 3H₂O, 2NaCO_Three・ 3H₂O₂, Na_FourP₂O₇・ 2H₂O₂2Na₂SO_Four・ H₂O₂・ 2H₂O), peroxyacid salts (eg K₂S₂O₈, K₂C₂O₆, K₂P₂O₈), Peroxy complex compounds (for example, K₂[Ti (O₂) C₂O_Four] 3H₂O, 4K₂SO_Four・ Ti (O₂) OH / SO_Four・ 2H₂O, Na_Three[VO (O₂) (C₂H_Four)₂] 6H₂O), permanganate (eg KMnO)_Four), Chromate (eg, K₂Cr₂O₇) Oxygenates, halogen elements such as iodine and bromine, perhalogenates (eg potassium periodate), high valent metal salts (eg potassium hexacyanoferrate) and thiosulfone There is an acid salt.
[0056]
Examples of organic oxidizing agents include quinones such as p-quinone, organic peroxides such as peracetic acid and perbenzoic acid, and compounds that release active halogens (for example, N-bromosuccinimide, chloramine T, An example is chloramine B).
[0057]
The light-sensitive material produced using the silver halide emulsion obtained in the present invention may have at least one light-sensitive emulsion layer on the support, preferably a blue color-sensitive layer, green-sensitive layer. At least one silver halide emulsion layer of a chromatic layer and a red color sensitive layer is provided. There are no particular restrictions on the number and order of the silver halide emulsion layers and the non-light-sensitive layers. A typical example is a silver halide photographic light-sensitive material having at least one color-sensitive layer composed of a plurality of silver halide emulsion layers having substantially the same color sensitivity but different sensitivity on a support. The photosensitive layer is a unit photosensitive layer having color sensitivity to any of blue light, green light, and red light. In a multilayer silver halide color photographic light-sensitive material, the unit photosensitive layer is generally used. Are arranged in the order of the red color-sensitive layer, the green color-sensitive layer, and the blue color-sensitive layer from the support side. However, depending on the purpose, the installation order may be reversed, or the installation order may be such that different photosensitive layers are contained in the same color-sensitive layer.
[0058]
The above-mentioned various additives are used in the light-sensitive material according to the present invention, but various additives can be used depending on the purpose.
These additives are described in more detail in Research Disclosure Item 17643 (December 1978), Item 18716 (November 1979), and Item 308119 (December 1989). These are summarized in the table below.
[0059]

[0060]
Further, in order to prevent deterioration of photographic performance due to formaldehyde gas, a compound capable of reacting with formaldehyde described in U.S. Pat. Nos. 4,411,987 and 4,435,503 is immobilized on a photosensitive material. It is preferable to add.
Various color couplers can be used in the present invention, and specific examples thereof are the above-mentioned Research Disclosure No. 17643, VII-CG and No. 307105, described in the patents described in VII-CG.
[0061]
【Example】
Examples of the present invention are shown below. However, the present invention is not limited to this embodiment.
(Example-1)
In the emulsion composed of tabular grains having an epitaxial portion, the effect obtained by providing the annular band in the host tabular grains and the effect provided by providing the main surface parallel layer in the present invention will be described.
[0062]
(Preparation of emulsion a)
1600 mL of an aqueous solution containing 1.2 g of KBr and 1.5 g of oxidized gelatin having an average molecular weight of 15000 was kept at 35 ° C. and stirred. AgNO_ThreeAn aqueous solution (2.7 g) and an aqueous halogen solution (containing 1.9 g of KBr and 1.2 g of the gelatin) were added over 30 seconds by the double jet method. After adding KBr aqueous solution (KBr3.2g), it heated up at 55 degreeC. After adding an aqueous solution containing 30 g of oxidized gelatin having an average molecular weight of 100,000, AgNO as the first growth_Three(175.3 g) The aqueous solution and the KBr aqueous solution were added by accelerating the flow rate for 40 minutes by the double jet method. At this time, the silver potential was kept at −20 mV with respect to the saturated calomel electrode. Then, AgNO as the second growth_Three(16.0 g) An aqueous solution and an aqueous KBr solution were added over 9 minutes by the double jet method. At this time, the silver potential was kept at −20 mV with respect to the saturated calomel electrode. Thereafter, an aqueous solution containing 14 g of normal gelatin having an average molecular weight of 100,000 was added.
[0063]
Next, the temperature is lowered to 40 ° C., and AgNO3 as the third growth_Three(9.9 g) An aqueous solution and an aqueous KBr solution were added over 9.5 minutes by the double jet method. At this time, the addition of the aqueous KBr solution was adjusted so that the silver potential monotonously changed from −30 mV at the start of the third growth to +44 mV at the end of the third growth with respect to the saturated calomel electrode. Thus, the host tabular grains before epitaxial deposition were completed.
Thereafter, sensitizing dyes I, II and III were added at a molar ratio of 7: 2: 1 at a ratio of 85% of the saturated coverage. 9.9 × 10 6 potassium hexacyanoruthenium (II)^-FiveMole (hereinafter referred to as 1 mol of silver in the host tabular grains) was added. AgNO_Three(9.6 g) An aqueous solution, KBr (1.6 g), a halogen aqueous solution containing NaCl (2.9 g) and KI (2.0 g) were added by the double jet method over 1 minute, whereby the apex of the host tabular grains An epitaxial portion joined to the portion was formed.
[0064]
Antifoggant I 1 × 10^-FourAfter the molar addition, the emulsion was washed with water at 35 ° C. according to a conventional method, deionized gelatin having an average molecular weight of 100,000 was added, and redispersed at 40 ° C. to adjust the pH to 6.5.
The temperature was raised to 50 ° C., and potassium thiocyanate, chloroauric acid, sodium thiosulfate and N, N-dimethylselenourea were added for optimum chemical sensitization. Antifoggant II II 3.2 × 10^-FourThe chemical sensitization was completed by adding a molar amount. This emulsion was designated as Emulsion a.
[0065]
Emulsion a was a tabular grain having an average equivalent-circle diameter of 0.66 μm, an equivalent-circle diameter variation coefficient of 22%, an average thickness of 0.066 μm, a thickness variation coefficient of 18%, and an average aspect ratio of 10. In addition, the ratio of the length of the side having the maximum length to the length of the side having the minimum length of 90% or more of the total projected area is 6 or less with the (111) plane being the main surface. It was occupied by square tabular grains. According to electron microscopic observation of the cut cross section of the particle, the average twin plane spacing was 0.008 μm and the coefficient of variation was 17%. As a result of observation with a transmission electron microscope at a low temperature, dislocation lines were observed in the epitaxial portion in 75% or more of the total projected area. This dislocation line was network-like. This emulsion does not have the annular band and the main surface parallel layer recommended in the present invention in the host tabular grains.
[0066]
[Chemical 1]

[0067]
[Chemical formula 2]

[0068]
(Preparation of emulsion b)
Emulsion b was prepared in the same manner except that the second growth was changed as follows in the preparation of emulsion a.
AgNO_Three(15.7 g) An aqueous solution and an aqueous KBr solution were added over 12 minutes by the double jet method. In the latter half of 6 minutes, 0.33 g of an AgI ultrafine grain emulsion prepared just before the addition was added in parallel with the above double jet in terms of KI mass. The AgI ultrafine grain emulsion was prepared by the method described in US Pat. No. 5,004,679. The average particle size of the AgI ultrafine particles was 9 nm, and the variation coefficient of the particle size distribution was 24%.
[0069]
Emulsion b has an average equivalent circle diameter, variation coefficient of equivalent circle diameter, average thickness, variation coefficient of thickness, average aspect ratio, ratio of the length of the side having the maximum length to the length of the side having the minimum length. The plane index of the main surface and the average twin plane spacing were almost the same as those of the emulsion a. As a result of observation with a transmission electron microscope at low temperature, dislocation lines were observed in the epitaxial part in 80% or more of the total projected area. This dislocation line was network-like. The emulsion has an annular band recommended in the present invention at a distance of 0.97 d or more from the center of the host tabular grain, where d is the distance from the center of the host tabular grain to the end of the grain. The annular band had a width of about 6 nm and a silver iodide content of 4 mol%.
[0070]
(Preparation of emulsion c)
Emulsion c was prepared in the same manner except that the second growth was changed as follows in the preparation of emulsion a.
AgNO_Three(15.4 g) An aqueous solution and an aqueous KBr solution were added over 12 minutes by the double jet method. In the latter half of 6 minutes, in parallel with the above double jet, 0.65 g of an AgI ultrafine grain emulsion prepared just before the addition was added in terms of KI mass. The AgI ultrafine grain emulsion was prepared by the method described in US Pat. No. 5,004,679. The average particle size of the AgI ultrafine particles was 9 nm, and the variation coefficient of the particle size distribution was 24%.
[0071]
Emulsion c has an average equivalent circle diameter, variation coefficient of equivalent circle diameter, average thickness, variation coefficient of thickness, average aspect ratio, ratio of the length of the side having the maximum length to the length of the side having the minimum length. The plane index of the main surface and the average twin plane spacing were almost the same as those of the emulsion a. As a result of observation with a transmission electron microscope at low temperature, dislocation lines were observed in the epitaxial part in 80% or more of the total projected area. This dislocation line was network-like. The emulsion has an annular band recommended in the present invention at a distance of 0.97 d or more from the center of the host tabular grain, where d is the distance from the center of the host tabular grain to the end of the grain. The annular band had a width of about 6 nm and a silver iodide content of 8 mol%.
[0072]
(Preparation of emulsion d)
Emulsion d was prepared in the same manner except that the second growth was changed as follows in the preparation of emulsion a.
AgNO_Three(14.7 g) An aqueous solution and an aqueous KBr solution were added over 12 minutes by the double jet method. In parallel with the above double jet, 1.25 g of an AgI ultrafine grain emulsion prepared just before the addition was added in terms of KI mass. The AgI ultrafine grain emulsion was prepared by the method described in US Pat. No. 5,004,679. The average particle size of the AgI ultrafine particles was 9 nm, and the variation coefficient of the particle size distribution was 24%.
[0073]
Emulsion d has an average equivalent circle diameter, variation coefficient of equivalent circle diameter, average thickness, variation coefficient of thickness, average aspect ratio, ratio of the length of the side having the maximum length to the length of the side having the minimum length. The plane index of the main surface and the average twin plane spacing were almost the same as those of the emulsion a. As a result of observation with a transmission electron microscope at a low temperature, dislocation lines were observed in the epitaxial portion over 85% of the total projected area. This dislocation line was network-like. This emulsion has an annular band recommended in the present invention at a distance of 0.95 d or more from the center of the host tabular grain, where d is the distance from the center of the host tabular grain to the end of the grain. The width of the annular band was about 12 nm, and the silver iodide content was 8 mol%.
[0074]
(Preparation of emulsion e)
Emulsion e was prepared in the same manner except that the third growth was changed as follows in the preparation of emulsion d.
AgNO_Three(9.9 g) An aqueous solution, an aqueous KI solution (6 mol% based on Ag), and an aqueous KBr solution were added over 9.5 minutes by the triple jet method. At this time, the addition of the aqueous KBr solution was adjusted so that the silver potential was +44 mV with respect to the saturated calomel electrode.
[0075]
Emulsion e has an average equivalent circle diameter, variation coefficient of equivalent circle diameter, average thickness, variation coefficient of thickness, average aspect ratio, ratio of the length of the side having the maximum length to the length of the side having the minimum length The plane index of the main surface and the average twin plane spacing were almost the same as those of the emulsion a. As a result of observation with a transmission electron microscope at a low temperature, dislocation lines were observed in the epitaxial portion over 85% of the total projected area. This dislocation line was network-like. This emulsion has an annular band recommended in the present invention at a distance of 0.95 d or more from the center of the host tabular grain, where d is the distance from the center of the host tabular grain to the end of the grain. The width of the annular band was about 14 nm, and the silver iodide content was in the range of 6-8 mol%. The emulsion has a main surface parallel layer recommended in the present invention in a region about 2 nm deep from the main surface of the host tabular grain. The main surface parallel layer had a silver iodide content of 6 mol% and a thickness of about 2 nm.
[0076]
(Preparation of emulsion f)
In the preparation of emulsion e, 0.35 g of KI aqueous solution was added in terms of KI mass after the third growth and before addition of the sensitizing dye.
Emulsion f has an average equivalent circle diameter, variation coefficient of equivalent circle diameter, average thickness, variation coefficient of thickness, average aspect ratio, ratio of the length of the side having the maximum length to the length of the side having the minimum length. The average twin plane spacing was almost the same as that of the emulsion a. As a result of observation with a transmission electron microscope at a low temperature, dislocation lines were observed in the epitaxial portion over 85% of the total projected area. This dislocation line was network-like. This emulsion has an annular band recommended in the present invention at a distance of 0.95 d or more from the center of the host tabular grain, where d is the distance from the center of the host tabular grain to the end of the grain. The width of the annular band was about 14 nm and the silver iodide content was in the range of 6-8 mol%. The emulsion has a main surface parallel layer recommended in the present invention in a region about 3 nm deep from the main surface of the host tabular grain. The main surface parallel layer had a silver iodide content of 9 to 13 mol% and a thickness of about 3 nm.
[0077]
An emulsion subjected to the above chemical sensitization under the coating conditions as shown in Table 1 below was applied to a cellulose triacetate film support provided with an undercoat layer, with a protective layer provided thereon. 1-1 to 6 were prepared.
[0078]
[Table 1]

[0079]
These samples were left under conditions of 40 ° C. and 70% relative humidity for 14 hours. Thereafter, the film was exposed for 1/100 second through a gelatin filter SC-50 manufactured by FUJIFILM Corporation and a continuous wedge.
Using a negative processor FP-350 manufactured by Fuji Photo Film Co., Ltd., color negative treatment was carried out by the conventional method. At that time, the color development processing time was 1 minute 15 seconds. Thereafter, the density of the treated sample was measured with a green filter.
[0080]
The sensitivity was evaluated by comparing the reciprocal of the exposure amount giving a density of fog plus 0.2. Table 2 shows the relative values when the sensitivity of 1-1 is 100.
Further, the gradation of the highlight portion where the exposure amount is large is evaluated by comparing the slopes of the curves at the density point 2.2 of the characteristic curve of each sample, and is also shown in Table 2.
Further, fog generated when subjected to pressure was evaluated as follows. First, each sample was bent at an angle of 20 ° for 5 seconds in an environment of 25 ° C. and 50% relative humidity with the emulsion surface facing inward. Next, development was performed under the condition that the processing time for color development was 2 minutes 45 seconds. The maximum density of the pressure fog in the bent portion of the samples thus obtained was compared. The results are shown in Table 2.
[0081]
[Table 2]

[0082]
As is apparent from the results in Table 2, the tabular emulsion having an epitaxial portion has a high sensitivity and a high gradation in the highlight portion by providing the annular band recommended in the present invention in the host tabular grain, and the pressure is increased. The fog density decreases. More preferably, the width of the annular band and the silver iodide content are within the ranges recommended in the present invention. In addition, it is clear from the results in Table 2 that the sensitivity further increases when the main surface parallel layer recommended in the present invention is provided.
[0083]
(Example-2)
The effect of having dislocation lines in the epitaxial portion in the emulsion of the present invention comprising tabular grains having an epitaxial portion and having a ring-shaped zone and a main surface parallel layer in the host tabular grains, and the main surface of the host tabular grains The effect of having a dislocation line above will be described.
[0084]
(Preparation of emulsion g)
1600 mL of an aqueous solution containing 1.2 g of KBr and 1.5 g of oxidized gelatin having an average molecular weight of 15000 was kept at 35 ° C. and stirred. AgNO_ThreeAn aqueous solution (2.7 g) and an aqueous halogen solution (containing 1.9 g of KBr and 1.2 g of the gelatin) were added over 30 seconds by the double jet method. After adding KBr aqueous solution (KBr3.2g), it heated up at 55 degreeC. After adding an aqueous solution containing 30 g of oxidized gelatin having an average molecular weight of 100,000, AgNO as the first growth_Three(175.3 g) The aqueous solution and the KBr aqueous solution were added by accelerating the flow rate for 40 minutes by the double jet method. At this time, the silver potential was kept at −20 mV with respect to the saturated calomel electrode. Then, AgNO as the second growth_Three(16.0 g) Aqueous solution, KI aqueous solution (8 mol% with respect to Ag), and KBr aqueous solution were added over 9 minutes by the triple jet method. At this time, the silver potential was kept at −20 mV with respect to the saturated calomel electrode. Thereafter, an aqueous solution containing 20 g of normal gelatin having an average molecular weight of 100,000 was added.
[0085]
Next, the temperature is lowered to 40 ° C., and AgNO3 as the third growth_Three(9.9 g) An aqueous solution, an aqueous KI solution (8 mol% based on Ag), and an aqueous KBr solution were added over 9 minutes by the triple jet method. At this time, the addition of the aqueous KBr solution was adjusted so that the silver potential monotonously changed from −30 mV at the start of the third growth to +44 mV at the end of the third growth with respect to the saturated calomel electrode. Thereafter, 0.3 g of KI aqueous solution was added in terms of KI mass.
Thus, the host tabular grains before epitaxial deposition were completed.
[0086]
Thereafter, sensitizing dyes I, II and III were added at a molar ratio of 7: 2: 1 at a ratio of 85% of the saturated coverage. 9.9 × 10 6 potassium hexacyanoruthenium (II)^-FiveMole (hereinafter referred to as 1 mol of silver in the host tabular grains) was added. AgNO_Three(9.6 g) An aqueous solution, KBr (1.6 g), a halogen aqueous solution containing NaCl (2.9 g) and KI (2.0 g) were added by the double jet method over 1 minute, whereby the apex of the host tabular grains An epitaxial portion joined to the portion was formed.
4 × 10 antifoggant II^{- 5}After the molar addition, the emulsion was washed with water at 35 ° C. according to a conventional method, deionized gelatin having an average molecular weight of 100,000 was added, and redispersed at 40 ° C. to adjust the pH to 6.5.
The temperature was raised to 50 ° C., and potassium thiocyanate, chloroauric acid, sodium thiosulfate and N, N-dimethylselenourea were added for optimum chemical sensitization. Antifoggant II II 3.2 × 10^-FourThe chemical sensitization was completed by adding a molar amount. This emulsion was designated as Emulsion g.
[0087]
Emulsion g was a tabular grain having an average equivalent-circle diameter of 0.66 μm, an equivalent-circle diameter variation coefficient of 22%, an average thickness of 0.066 μm, a thickness variation coefficient of 18%, and an average aspect ratio of 10. In addition, the ratio of the length of the side having the maximum length to the length of the side having the minimum length of 90% or more of the total projected area is 6 or less with the (111) plane being the main surface. It was occupied by square tabular grains. According to electron microscopic observation of the cut cross section of the particle, the average twin plane spacing was 0.008 μm and the coefficient of variation was 17%. As a result of observation with a transmission electron microscope at low temperature, dislocation lines were observed in the epitaxial part in 80% or more of the total projected area. This dislocation line was network-like. Dislocation lines on the main surface of the host tabular grain were not observed in almost all grains. This emulsion has an annular band recommended in the present invention at a distance of 0.95 d or more from the center of the host tabular grain, where d is the distance from the center of the host tabular grain to the end of the grain. The width of the annular band was about 13 nm, and the silver iodide content was 8 mol%. The emulsion has a main surface parallel layer recommended in the present invention in a region about 3 nm deep from the main surface of the host tabular grain. The main surface parallel layer had a silver iodide content of 8 to 15 mol% and a thickness of about 3 nm.
[0088]
(Preparation of emulsion h)
Emulsion h was prepared in the same manner as in the preparation of Emulsion g, except that the conditions for forming the epitaxial part after addition of the sensitizing dye and potassium hexacyanoruthenium (II) were changed as follows.
AgNO_Three(9.6 g) By adding a halogen aqueous solution containing an aqueous solution, KBr (5.1 g), NaCl (1.1 g), and KI (2.0 g) over 1 minute by the double jet method, the top of the host tabular grains An epitaxial portion joined to the portion was formed.
[0089]
Emulsion h has an average equivalent circle diameter, variation coefficient of equivalent circle diameter, average thickness, variation coefficient of thickness, average aspect ratio, ratio of the length of the side having the maximum length to the length of the side having the minimum length. The plane index and average twin plane spacing of the main surface were almost the same as those of the emulsion g. As a result of observation with a transmission electron microscope at a low temperature, dislocation lines were not observed in the epitaxial part in almost all the particles. Also, dislocation lines on the main surface of the host tabular grain were not observed in almost all grains. Regarding the distribution of the annular band and the main surface parallel layer in the host tabular grains, and the silver iodide content in these regions. It was almost the same as the above emulsion g.
[0090]
(Preparation of emulsion i)
Emulsion i was prepared in the same manner as in the preparation of Emulsion g except that the conditions for the formation of the epitaxial part after addition of the sensitizing dye and potassium hexacyanoruthenium (II) were changed as follows.
AgNO_Three(9.6 g) Aqueous solution and NaCl (8.7 g) aqueous solution were added over 0.4 min by double jet method, then AgNO_Three(6.7 g) An epitaxial solution bonded to the apex of the host tabular grain by adding an aqueous solution and a halogen aqueous solution containing KBr (3.1 g) and KI (1.3 g) over a period of 0.8 minutes by the double jet method. Part was formed.
[0091]
Emulsion i has an average equivalent circle diameter, variation coefficient of equivalent circle diameter, average thickness, variation coefficient of thickness, average aspect ratio, ratio of the length of the side having the maximum length to the length of the side having the minimum length The plane index and average twin plane spacing of the main surface were almost the same as those of the emulsion g. As a result of transmission electron microscope observation at a low temperature, dislocation lines were observed in the epitaxial portion of almost all particles. Dislocation lines coexisted with mesh and streaks. Also, dislocation lines on the main surface of the host tabular grain were not observed in almost all grains. Regarding the distribution of the annular band and the main surface parallel layer in the host tabular grains, and the silver iodide content in these regions. It was almost the same as the above emulsion g.
[0092]
(Preparation of emulsion j)
In the preparation of emulsion g, the first growth of AgNO_ThreeWhen 140 g was added, emulsion j was prepared by adding a step of adding 3.0 g of the AgI ultrafine grain emulsion prepared just before the addition in terms of KI mass. The addition of the AgI ultrafine grain emulsion was performed at once in 0.2 minutes. An AgI ultrafine grain emulsion was prepared by the method described in US Pat. No. 5,004,679. The average particle size of the AgI ultrafine particles was 9 nm, and the variation coefficient of the particle size distribution was 24%.
[0093]
Emulsion j was a tabular grain having an average equivalent-circle diameter of 0.60 μm, an equivalent-circle diameter variation coefficient of 22%, an average thickness of 0.08 μm, a thickness variation coefficient of 19%, and an average aspect ratio of 7.5. In addition, the ratio of the length of the side having the maximum length to the length of the side having the minimum length of 90% or more of the total projected area is 6 or less with the (111) plane being the main surface. It was occupied by square tabular grains. The average twin plane spacing and its coefficient of variation were the same as those of Emulsion g. As a result of observation with a transmission electron microscope at low temperature, dislocation lines were observed in the epitaxial part in 80% or more of the total projected area. This dislocation line was network-like. Dislocation lines on the main surface of the host tabular grains were observed in tabular grains of 80% or more of the total projected area, and the average number was 5 to 6. This dislocation line was streaked. This emulsion has two annular bands recommended in the present invention at a distance of 0.77 d or more from the center of the host tabular grain, where d is the distance from the center of the host tabular grain to the end of the grain. One is distributed in the lateral direction with a width of about 12 nm from around 0.77d from the center of the host tabular grain, and the other is lateral with a width of about 13 nm from the vicinity of 0.96d from the center of the host tabular grain. It was distributed in the direction. The silver iodide content was 22-30 mol% for the former and 8 mol% for the latter. The emulsion has a main surface parallel layer recommended in the present invention in a region from the host tabular grain main surface to a depth of about 8 nm. The main surface parallel layer had a silver iodide content of 8 to 25 mol% and a thickness of about 8 nm.
[0094]
(Preparation of emulsion k)
In the preparation of emulsion g, first growth of AgNO_ThreeWhen 140 g was added, emulsion k was prepared by adding a step of adding 6.0 g of the AgI ultrafine grain emulsion prepared just before the addition in terms of KI mass. The addition of the AgI ultrafine grain emulsion was performed all at once in 0.4 minutes. An AgI ultrafine grain emulsion was prepared by the method described in US Pat. No. 5,004,679. The average particle size of the AgI ultrafine particles was 9 nm, and the variation coefficient of the particle size distribution was 24%.
[0095]
Emulsion k was a tabular grain having an average equivalent circle diameter of 0.60 μm, a variation coefficient of equivalent circle diameter of 22%, an average thickness of 0.08 μm, a variation coefficient of thickness of 19%, and an average aspect ratio of 7.5. In addition, the ratio of the length of the side having the maximum length to the length of the side having the minimum length of 90% or more of the total projected area is 6 or less with the (111) plane being the main surface. It was occupied by square tabular grains. The average twin plane spacing and its coefficient of variation were the same as those of Emulsion g. As a result of observation with a transmission electron microscope at low temperature, dislocation lines were observed in the epitaxial part in 80% or more of the total projected area. This dislocation line was network-like. Dislocation lines on the main surface of the host tabular grains were observed in tabular grains of 80% or more of the total projected area, and the average number was about 16. This dislocation line was streaked. This emulsion has two annular bands recommended in the present invention at a distance of 0.77 d or more from the center of the host tabular grain, where d is the distance from the center of the host tabular grain to the end of the grain. One is distributed in the lateral direction with a width of about 20 nm from the vicinity of the center of the host tabular grain and about 13 nm from the vicinity of the center of the host tabular grain with a width of about 13 nm. It was distributed in the direction. The silver iodide content was 22-30 mol% for the former and 8 mol% for the latter. The emulsion has a main surface parallel layer recommended in the present invention in a region from the host tabular grain main surface to a depth of about 8 nm. The main surface parallel layer had a silver iodide content of 8-30 mol% and a thickness of about 8 nm.
[0096]
Sample No. was applied in the same manner as Example 1. Table 3 shows the results of preparing 2-1 to 5 and evaluating the photographic characteristics.
[0097]
[Table 3]

[0098]
As is apparent from Table 3, in the emulsion of the present invention, the emulsion composed of grains having dislocation lines in the epitaxial part has a higher sensitivity and the highlight part than the emulsion composed of grains having no dislocation lines in the epitaxial part. The gradation is hard. Further, the pressure fog density is preferably slightly low. The pressure fog density can be further reduced by providing dislocation lines on the main surface. However, if the number of dislocation lines on the main surface is too large, the sensitivity tends to decrease and soften. It is clear from the results.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an example of an annular band of the present invention (exposed to the particle surface at the main surface and side surfaces) (when passing through the center of the particle and cutting along a plane perpendicular to the main surface) Sectional view).
FIG. 2 is a schematic view showing an example of an annular band of the present invention (exposed to the particle surface at the main surface) (a cross-sectional view taken along a plane passing through the center of the particle and perpendicular to the main surface) ).
FIG. 3 is a schematic view showing an example of an annular band of the present invention (an example embedded without being exposed to the particle surface) (when passing through the center of the particle and cutting along a plane perpendicular to the main surface) Sectional view).
FIG. 4 is a schematic diagram showing an example in which the annular band of the present invention and a main surface parallel layer having a high silver iodide content are joined (through a plane passing through the center of the grain and perpendicular to the main surface). Sectional view when cut).
FIG. 5 is a transmission electron micrograph (magnification: 80,000 times) of the silver halide emulsion grain of the present invention, in which streaky dislocation lines are clearly observed in the epitaxial part indicated by the arrow.
FIG. 6 is a transmission electron micrograph (magnification: 80,000 times) of the silver halide emulsion grain of the present invention, and a network-like dislocation line is clearly observed in the epitaxial portion indicated by an arrow.

Claims (2)

Epitaxially bonded silver halide flat plate in which variation coefficient of equivalent circle diameter of all grains is 30% or less and 70% or more of the total projected area satisfies the following requirements (i), (ii) , (iii) and ( iv ) A silver halide photographic emulsion characterized by being occupied by grains.
(I) Silver iodochlorobromide grains having a (111) plane as the main surface.
(Ii) It has an epitaxial portion at at least one apex of the host tabular grain.
(Iii) When the distance from the center of the host tabular grain to the edge of the grain is d, a ring band having a silver iodide content of 4 mol% or more in a region 0.7 d or more from the center ; A region adjacent to the inner side in the lateral direction, the silver iodide content of which is lower by 0.5 mol% or more than the silver iodide content of the annular band.
( Iv ) Within a depth of 10 nm from the main surface, it has a main surface parallel layer parallel to the main surface and having a silver iodide content of 4 mol% or more. Epitaxial bonding in which the coefficient of variation of the equivalent circle diameter of all particles is 30% or less and 70% or more of the total projected area satisfies the following requirements (i), (ii), (iii) , ( iv ) and (vi) A silver halide photographic emulsion characterized by occupying silver halide tabular grains.
(I) Silver iodochlorobromide grains having a (111) plane as the main surface.
(Ii) It has an epitaxial portion at at least one apex of the host tabular grain.
(Iii) When the distance from the center of the host tabular grain to the edge of the grain is d, a ring band having a silver iodide content of 4 mol% or more in a region 0.7 d or more from the center ; A region adjacent to the inner side in the lateral direction, the silver iodide content of which is lower by 0.5 mol% or more than the silver iodide content of the annular band.
( Iv ) Within a depth of 10 nm from the main surface, it has a main surface parallel layer parallel to the main surface and having a silver iodide content of 4 mol% or more.
(Vi) It has at least one dislocation line on the main surface.

Images