JP3843622B2 - Silver halide photographic emulsion - Google Patents

Description

によって粒子厚さの分布の広さを定義したとき３５％以下のものが好ましく、より好ましくは２５％以下、更に好ましくは２０％以下のものである。
【００４１】
本発明における平板粒子は核となるコアと該コアを被覆するシェルとから構成される粒子であることが好ましく、シェルは１層あるいはそれ以上の層によって形成される。
【００４２】
本発明の平板粒子が上記コア／シェル型粒子からなる場合、コアとシェルのハロゲン組成は本発明の要件を満たす範囲であれば、任意に選ぶ事ができるが、コア、シェルともに、平均沃化銀含有率は、５ｍｏｌ％以下が好ましく、３ｍｏｌ％以下がより好ましい。また、シェルとコアの平均沃化銀含有率の差は２ｍｏｌ％以下であることが好ましい。
【００４３】
コアの占める割合は、粒子全体の銀量の１〜６０％とするのが好ましく、４〜４０％が更に好ましい。
【００４４】
本発明における平板粒子の粒子全体の平均沃化銀含有率は１０ｍｏｌ％以下が好ましく、７ｍｏｌ％以下がより好ましく、更に好ましくは４ｍｏｌ％以下である。
【００４５】
本発明の平板粒子は上記のように沃臭化銀を主として含有する乳剤であるが、本発明の効果を損なわない範囲で他の組成のハロゲン化銀、例えば塩化銀を含有させることができる。
【００４６】
本発明の平板粒子の形成手段としては、当該分野でよく知られている種々の方法を用いることができる。すなわち、シングル・ジェット法，コントロールド・ダブルジェット法、コントロールド・トリプルジェット法等を任意に組み合わせて使用することができるが、高度な単分散粒子を得るためには、ハロゲン化銀粒子の生成される液相中のｐＡｇをハロゲン化銀粒子の成長速度に合わせてコントロールすることが重要である。ｐＡｇ値としては７．０〜１１．５の領域を使用し、好ましくは７．５〜１１．０、更に好ましくは８．０〜１０．５の領域を使用することができる。
【００４７】
添加速度の決定にあたっては、特開昭５４−４８５２１号、特開昭５８−４９９３８号に記載の技術を参考にできる。
【００４８】
本発明の平板粒子の製造時に、アンモニア、チオエーテル等の公知のハロゲン化銀溶剤を存在させることもできるし、ハロゲン化銀溶剤を使用しなくても良い。
【００４９】
本発明の平板粒子は、潜像が主として表面に形成される粒子あるいは主として粒子内部に形成される粒子いずれであっても良い。
【００５０】
本発明の平板粒子は、分散媒の存在下に即ち、分散媒を含む溶液中で製造される。ここで、分散媒を含む水溶液とは、ゼラチンその他の親水性コロイドを構成し得る物質(バインダーとなり得る物質など)により保護コロイドが水溶液中に形成されているものをいい、好ましくはコロイド状の保護ゼラチンを含有する水溶液である。
【００５１】
本発明を実施する際、上記保護コロイドとしてゼラチンを用いる場合は、ゼラチンは石灰処理されたものでも、酸を使用して処理されたものでもどちらでもよい。ゼラチンの製法の詳細はアーサー・グアイス著、ザ・マクロモレキュラー・ケミストリー・オブ・ゼラチン（アカデミック・プレス、１９６４年発行）に記載がある。
【００５２】
保護コロイドとして用いることができるゼラチン以外の親水性コロイドとしては、例えばゼラチン誘導体、ゼラチンと他の高分子とのグラフトポリマー、アルブミン、カゼイン等の蛋白質；ヒドロキシエチルセルロース、カルボキシメチルセルロース、セルロース硫酸エステル類等フ如きセルロース誘導体、アルギン酸ソーダ、澱粉誘導体などの糖誘導体；ポリビニルアルコール、ポリビニルアルコール部分アセタール、ポリ−Ｎ−ビニルピロリドン、ポリアクリル酸、ポリメタクリル酸、ポリアクリルアミド、ポリビニルイミダゾール、ポリビニルピラゾール等の単一あるいは共重合体の如き多種の合成親水性高分子物質がある。
【００５３】
ゼラチンの場合は、パギー法においてゼリー強度２００以上のものを用いることが好ましい。
【００５４】
本発明のハロゲン化銀乳剤は、ハロゲン化銀粒子の成長終了後に、不要な可溶性塩類を除去したものであってもよいし、あるいは含有させたままのものでも良い。
【００５５】
また、特開昭６０−１３８５３８号記載の方法のように、ハロゲン化銀成長の任意の点で脱塩を行なう事も可能である。該塩類を除去する場合には、リサーチ・ディスクロージャー（Ｒｅｓｅａｒｃｈ Ｄｉｓｃｌｏｓｕｒｅ、以下ＲＤと略す）１７６４３号ＩＩ項に記載の方法に基づいて行なうことができる。さらに詳しくは、沈澱形成後、あるいは物理熟成後の乳剤から可溶性塩を除去するためには、ゼラチンをゲル化させて行なうヌーデル水洗法を用いても良く、また無機塩類、アニオン性界面活性剤、アニオン性ポリマー（たとえばポリスチレンスルホン酸）、あるいはゼラチン誘導体（たとえばアシル化ゼラチン、カルバモイル化ゼラチンなど）を利用した沈澱法（フロキュレーション）を用いても良い。
【００５６】
本発明において、個々のハロゲン化銀粒子の沃化銀含有率及び平均沃化銀含有率は、ＥＰＭＡ法（Ｅｌｅｃｔｒｏｎ Ｐｒｏｂｅ Ｍｉｃｒｏ Ａｎａｌｙｚｅｒ法）を用いることにより求めることが可能である。この方法は、乳剤粒子を互いに接触しないように良く分散したサンプルを作成し、電子ビームを照射する電子線励起によるＸ線分析により極微小な部分の元素分析が行える。ＥＰＭＡ法は、測定方法の違いにより、ＴＥＭ（透過型）とＳＥＭ（走査型）に分類され、またそれぞれがＷＤＳ（波長分散型）とＥＤＳ（エネルギー分散型）に分類される。ＥＰＭＡ法を用いて、各粒子から放射される銀及び沃度の特性Ｘ線強度を求めることにより、個々の粒子のハロゲン組成が決定できる。少なくとも５０個の粒子についてＥＰＭＡ法により沃化銀含有率を求めれば、それらの平均から平均沃化銀含有率が求められる。
【００５７】
本発明における平板粒子は、粒子間の沃化銀含有率がより均一になっていることが好ましい。ＥＰＭＡ法により粒子間の沃化銀含有率の分布を測定した時に、相対標準偏差すなわち個々の粒子の沃化銀含有率を特性値とした場合の標準偏差／平均値×１００（％）が３０％以下、更に２０％以下であることが好ましい。
【００５８】
また、本発明の構成の一つとして、全ハロゲン化銀粒子の投影面積の５０％以上の粒子が、粒子中心部から粒子端部に向けて沃化銀含有率が緩慢連続変化する平板粒子であるという条件を必要とするが、該条件に関しても、測定ビーム径を充分絞った、ＥＰＭＡ法で測定することができる。以下に該条件について、詳しく説明する。
【００５９】
平板状ハロゲン化銀粒子の主平面に対して垂直な方向から見て、平板粒子の主平面の中心より、辺に垂直な線分を引き、この線分上に線分の長さの５〜１５％おきに点をとり、各点の主平面に垂直な成分、すなわち測定スポット径と粒子厚さ分の高さを有する円筒部分の平均沃化銀含有率を測定する。このとき測定スポットは４０ｎｍ以下に絞ることが必要である。また、試料の損傷を考慮して、測定温度は、−１００℃以下に冷却することが必要である。各測定点における積算時間は３０秒以上とることとする。測定スポット各点間の沃化銀含有率変化は、２つの測定点間での、沃化銀含有率測定値（ｍｏｌ％）の差を測定点間の距離で割った値とし、粒子中心から外側に向けて増加する場合をプラス、減少する場合をマイナスとする。本発明では、中心から辺方向での各点間の沃化銀含有率変化が−０．０３ｍｏｌ％／ｎｍ〜＋０．０３ｍｏｌ％／ｎｍの範囲内である場合を、粒子中心部から粒子端部に向けて沃化銀含有率が緩慢連続変化すると定義する。該沃化銀含有率変化は、−０．０１ｍｏｌ％／ｎｍ〜＋０．０２ｍｏｌ％／ｎｍであることが好ましく、０．００ｍｏｌ％／ｎｍ〜＋０．０１ｍｏｌ％／ｎｍであることがより好ましい。
【００６０】
沃化銀含有率が緩慢連続変化する平板粒子の比率は、全ハロゲン化銀粒子の投影面積に対して、７０％以上であることが好ましく、９０％以上であることがさらに好ましい。
【００６１】
本発明の平板粒子の表面のハライド組成は、ＸＰＳ法（Ｘ−ｒａｙ Ｐｈｏｔｏｅｌｅｃｔｒｏｎ Ｓｐｅｃｔｒｏｓｃｏｐｙ法：Ｘ線光電子分光法）によって次のように求められる。
【００６２】
ＸＰＳ法は従来から、ハロゲン化銀粒子表面の沃化銀含有率を求める方法として用いられており、特開平２−２４１８８号等に開示されている。しかし、室温で測定を行った場合、Ｘ線照射に伴う試料が破壊されるため、最表層の正確な沃化銀含有率は求められなかった。本発明者らは試料を破壊の起きない温度、具体的には−１１０℃以下程度にまで冷却する事により、表層の沃化銀含有率を正確に求めることに成功した。その結果、特にコア／シェル粒子のような表面と内部の組成が異なる粒子や、最表面に高沃度層や低沃度層が局在している粒子では、室温での測定値はＸ線照射によるハロゲン化銀の分解とハライド（特に沃度）の拡散のために真の組成とは大きく異なることが明らかになった。
【００６３】
本発明で用いられるＸＰＳ法とは具体的には次の通りである。乳剤に蛋白質分解酵素（プロナーゼ）０．０５重量％水溶液を加え、４５℃で３０分間攪拌してゼラチンを分解した。これを遠心分離して乳剤粒子を沈降させ、上澄み液を除去する。次に蒸留水を加えて乳剤粒子を蒸留水中に分散させ、遠心分離し、上澄み液を除去する。乳剤粒子を水中に分散させ、鏡面研磨したシリコンウエハー上に薄く塗布して測定試料とする。このようにして作成した試料を用いて、ＸＰＳによる表面沃度測定を行った。Ｘ線照射による試料の破壊を防ぐため、試料はＸＰＳ測定用チャンバー内で−１１０〜−１２０℃に冷却した。プローブ用Ｘ線としてＭｇＫαをＸ線源電圧１５ｋＶ、Ｘ線源電流４０ｍＡで照射し、Ａｇ３ｄ_5/2、Ｂｒ３ｄ、Ｉ３ｄ_3/2電子について測定した。測定されたピークの積分強度を感度因子（Ｓｅｎｓｉｔｉｖｉｔｙ Ｆａｃｔｏｒ）で補正し、これらの強度比から表面のハライド組成を求めた。本発明におけるハロゲン化銀粒子表面の沃化銀含有率とは、上記のような方法で求めることのできるハロゲン化銀粒子の最表層の沃化銀含有率のことである。ハロゲン化銀粒子の最表層とは、ハロゲン化銀粒子の最表面を含む粒子の最外層であって、粒子の最表面から５０Åまでの深さの層をいう。
【００６４】
本発明における平板粒子は、粒子表面の沃化銀含有率が粒子の平均沃化銀含有率よりも高いことが好ましい。すなわち、粒子表面の沃化銀含有率／平均沃化銀含有率＝１．１〜８の関係を満たすことが好ましく、更に好ましくは、粒子表面の沃化銀含有率／平均沃化銀含有率＝１．３〜５の関係を満たすものである。
【００６５】
本発明のハロゲン化銀乳剤は、１粒子当たり３０本以上の転位線をフリンジ部に有する平板粒子が、全投影面積の５０％以上を占めることを特徴とする。１粒子当たり３０本以上の転位線をフリンジ部に有する粒子の全投影面積に占める割合は、好ましくは６０％であり、より好ましくは７０％である。
【００６６】
ハロゲン化銀粒子の転位は、例えば、Ｊ．Ｆ．Ｈａｍｉｌｔｏｎ、Ｐｈｏｔ．Ｓｃｉ．Ｅｎｇ．、ｖｏｌ１１、５７（１９６７）や、Ｔ．Ｓｈｉｏｚａｗａ、Ｊ．Ｓｏｃ．Ｐｈｏｔｏ．Ｓｃｉ．Ｊａｐａｎ、ｖｏｌ３５、２１３（１９７２）に記載の、低温での透過型電子顕微鏡を用いた直接的な方法により観察することができる。即ち、乳剤から粒子に転位が発生する程の圧力をかけないよう注意して取り出したハロゲン化銀粒子を電子顕微鏡観察用のメッシュにのせ、電子線による損傷（プリントアウト等）を防ぐように試料を冷却した状態で透過法により観察を行う。この時、粒子の厚みが厚いほど、電子線が透過し難くなるので、高圧型（０．２５μｍの厚さの粒子に対し２００ｋＶ以上）の電子顕微鏡を用いた方がより鮮明に観察することができる。
【００６７】
このような方法により得られた粒子の写真より、主平面に対して垂直な方向から見た場合の各粒子についての転位の位置及び数を求めることができる。
【００６８】
本発明において、転位線をフリンジ部に有するとは、平板粒子の外周部近傍や稜線近傍、あるいは頂点近傍に転位線が存在することである。具体的には、フリンジ部とは、平板粒子を主平面に垂直に観察し、平板粒子の主平面の中心すなわち主平面を２次元図形ととらえた場合の重心と頂点とを結んだ線分の長さをＬとしたとき、各頂点に関して中心からの距離が０．５０Ｌである点を結んだ図形より外側の領域を指す。
【００６９】
本発明のハロゲン化銀乳剤は、全ハロゲン化銀粒子の投影面積の５０％以上が、転位線が上記のフリンジ部のみに限定された平板粒子であることが好ましい。より好ましくは、転位線がフリンジ部のみに限定された平板粒子が占める割合は、全ハロゲン化銀粒子の投影面積の６０％以上であり、さらに好ましくは７０％以上である。また、転位線が限定される領域は、主平面の中心と頂点とを結んだ線分上の、中心からの距離が０．７０Ｌの点を結んだ図形より外側の領域であることがより好ましく、０．８０Ｌである点を結んだ図形より外側の領域であることがさらに好ましい。
【００７０】
転位線の方向はおおよそ中心から外表面(側面)に向かう方向であるが、しばしば蛇行している。
【００７１】
ハロゲン化銀粒子への転位線の導入法としては、例えば沃化カリウムのような沃素イオンを含む水溶液と水溶性銀塩溶液をダブルジェットで添加する方法、沃素イオンを含む溶液のみを添加する方法、沃化銀を含む微粒子乳剤を添加する方法、又は特開平６−１１７８１号に記載されているような沃素イオン放出剤を用いる方法等が知られている。
【００７２】
本発明の乳剤を得るために有効な方法は、沃素イオン放出剤を用いる方法である。沃素イオン放出剤とは、
Ｒ¹−Ｉ
の一般式であらわされる、塩基あるいは求核試薬との反応によって、沃素イオンを放出する化合物である。Ｒ¹は１価の有機基をあらわす。Ｒ¹は、アルキル基、アルケニル基、アルキニル基、アリール基、アラルキル基、複素環基、アシル基、カルバモイル基、アルキルオキシカルボニル基、アリールオキシカルボニル基、アルキルスルホニル基、アリールスルホニル基、スルファモイル基であることが好ましい。Ｒ¹は炭素数３０以下の有機基であることが好ましく、２０以下であることがより好ましく、１０以下であることがさらに好ましい。
【００７３】
またＲ¹は置換基を有していることが好ましく、置換基がさらに他の置換基で置換されていてもよい。
【００７４】
好ましい該置換基として、ハロゲン原子、アルキル基、アルケニル基、アルキニル基、アリール基、アラルキル基、複素環基、アシル基、アシルオキシ基、カルバモイル基、アルキルオキシカルボニル基、アリールオキシカルボニル基、アルキルスルホニル基、アリールスルホニル基、スルファモイル基、アルコキシ基、アリールオキシ基、アミノ基、アシルアミノ基、ウレイド基、ウレタン基、スルホニルアミノ基、スルフィニル基、リン酸アミド基、アルキルチオ基、アリールチオ基、シアノ基、スルホ基、カルボキシル基、ヒドロキシ基、ニトロ基があげられる。
【００７５】
沃素イオン放出剤Ｒ¹−Ｉとしては、ヨードアルカン類、ヨードアルコール、ヨードカルボン酸、ヨードアミドおよびこれらの誘導体が好ましく、ヨードアミド、ヨードアルコールおよびこれらの誘導体がより好ましい、複素環基で置換されたヨードアミド類がさらに好ましく、最も好ましい例は、（ヨードアセトアミド）ベンゼンスルフォン酸塩である。
【００７６】
好ましく用いることのできる沃素イオン放出剤の具体例を以下に示す。
【００７７】
【化１】

【００７８】
沃素イオン放出剤と求核試薬を反応させて、沃素イオンを放出させる場合、求核試薬として、水酸化物イオン、亜硫酸イオン、チオ硫酸イオン、スルフィン酸塩、カルボン酸塩、アンモニア、アミン類、アルコール類、尿素類、チオ尿素類、フェノール類、ヒドラジン類、スルフィド類、ヒドロキサム酸類などを用いることができ、水酸化物イオン、亜硫酸イオン、チオ硫酸イオン、スルフィン酸塩、カルボン酸塩、アンモニア、アミン類が好ましく、水酸化物イオン、亜硫酸イオンがより好ましい。
【００７９】
本発明者らは沃素イオン放出剤を用いて、沃素イオンを放出させる条件を調節することにより本発明の乳剤が製造できることを見い出した。以下に、本発明の乳剤を製造するために、好ましい沃素イオン放出反応条件を記す。
【００８０】
本発明の乳剤を製造する際の、沃素イオン放出反応において、添加した沃素イオン放出剤の５０％が３０秒から１８０秒以内の時間内に沃素イオンを放出することが好ましい。沃素イオンの放出速度は、反応中のｐＡｇをモニターすることによって求めることができる。ｐＡｇから沃素イオン放出量への換算は、ＫＩのような水溶性沃化物を用いて、あらかじめ検量線を作成しておくことにより可能である。
【００８１】
沃素イオンの放出速度は、沃素イオン放出剤及び求核剤の添加量、沃素イオン放出剤及び求核剤のモル比、求核剤濃度、ｐＨ、温度によって調節することができる。
【００８２】
本発明の乳剤を製造する際の、沃素イオン放出反応において、反応温度は４５℃以下であることが好ましく、４０℃以下であることがより好ましく、３５度以下であることがさらに好ましい。ｐＢｒは１．５０以下であることが好ましく、１．３０以下であることがより好ましく、１．１０以下であることがさらに好ましい。
【００８３】
添加する沃素イオン放出剤の量は粒子成長終了後の、総銀ｍｏｌ量に対して、３．５ｍｏｌ％以下であることが好ましく、１．５ｍｏｌ％以下であることがより好ましく、１．０ｍｏｌ％以下であることがさらに好ましい。
【００８４】
また、沃素イオン放出反応時に、求核剤を用いる場合、求核剤が水酸化物イオンのみであれば、ｐＨを９．０以上１２．０以下の条件で反応を行うことが好ましく、ｐＨ１０．０以上１１．０以下であることがより好ましい。求核剤が水酸化物イオン以外である場合、求核剤の量はモル比にして、沃素イオン放出剤の量の０．２５倍以上２．０倍以下であることが好ましく、０．５０倍以上１．５倍以下であることがより好ましく、０．８０倍以上１．２倍以下であることがさらに好ましい。求核剤が水酸化物イオン以外である場合の、沃素イオン放出反応時のｐＨは、８．５以上１０．５以下であることが好ましく、９．０以上１０．０以下であることがより好ましい。求核剤は沃素イオン放出剤を添加開始した後に添加することが好ましく、沃素イオン放出剤の添加が終了した後に添加することがより好ましい。
【００８５】
本発明で、転位線導入位置とは、上記の方法で、沃化物イオンを粒子に導入した部分のことである。
【００８６】
本発明の構成の一つのハロゲン化銀乳剤は、アスペクト比が５以上であり、かつ、フリンジ部に転位線を３０本以上有し、かつ、粒子中心部から粒子端部に向けて沃化銀含有率が緩慢連続変化する平板状ハロゲン化銀粒子を含有する。該平板粒子は、全ハロゲン化銀粒子の投影面積の３０％以上、より好ましくは４０％以上、最も好ましくは５０％以上である。
【００８７】
本発明の構成のひとつでは、沃化銀輪郭を有する平板粒子は、全ハロゲン化銀粒子の投影面積の２０％以下であることが必要である。沃化銀輪郭を有する平板粒子は好ましくは全ハロゲン化銀粒子の投影面積の１５％未満であり、より好ましくは１０％未満であり、さらに好ましくは５％未満であり、最も好ましくは０％である。ただし、６００個以上の粒子について、観察を行うものとする。
【００８８】
沃化銀輪郭とは、本発明者らが定義した用語であり、転位線と同じ方法で観察できる。本発明においては、ＴＥＭ観察において、転位線導入位置付近に見られる、粒子外周形状とほぼ相似形で、数ｎｍ〜数１０ｎｍの幅をもった輪郭線からなる部分を沃化銀輪郭と定義する。ＥＰＭＡ法でこの部分の沃化銀含有率を調べると、８ｍｏｌ％〜１５ｍｏｌ％の値を示す。転位線導入と同時に生じた沃化銀含有率の高い層である。沃化銀含有率の違いにより、電子線透過／散乱率が他の部分と異なり、ＴＥＭで観察されるものと考察する。図１に沃化銀輪郭の例を示す。
【００８９】
本発明の好ましい形態として、平板粒子のフリンジ部に少なくとも１種以上の多価金属化合物を含有する。多価金属化合物をハロゲン化銀粒子中に含有させることを、メタルドープあるいは単にドープという。
【００９０】
メタルドープは当業界では良く知られた技術である。例えば，イリジウム錯体をハロゲン化銀にドープすると電子捕獲中心となることがＬｅｕｂｎｅｒによって報告されている（Ｔｈｅ Ｊｏｕｒｎａｌ ｏｆ ＰｈｏｔｏｇｒａｐｈｉｃＳｃｉｅｎｃｅ Ｖｏｌ．３１，９３（１９８３））。メタルドープに用いる金属化合物をメタルドーパントあるいは単にドーパントという。本発明において、１種以上のメタルドーパントを粒子中の任意の位置に存在させる事ができるが、上記の通り、好ましい形態は平板粒子のフリンジ部に少なくとも１種以上の多価金属化合物を含有させることである。
【００９１】
本発明において、メタルドーパントとしてＭｇ、Ａｌ、Ｃａ、Ｓｃ、Ｔｉ、Ｖ、Ｃｒ、Ｍｎ、Ｆｅ、Ｃｏ、Ｎｉ、Ｃｕ、Ｚｎ、Ｇａ、Ｇｅ、Ｓｒ、Ｙ、Ｚｒ、Ｎｂ、Ｍｏ、Ｔｃ、Ｒｕ、Ｒｈ、Ｐｄ、Ｃｄ、Ｓｎ、Ｂａ、Ｃｅ、Ｅｕ、Ｗ、Ｒｅ、Ｏｓ、Ｉｒ、Ｐｔ、Ｈｇ、Ｔｌ、Ｐｄ、Ｂｉ、Ｉｎ等の金属化合物を好ましく用いることができる。
【００９２】
またドープする金属化合物は、単塩または金属錯体から選択することが好ましい。金属錯体から選択する場合、６配位、５配位、４配位、２配位錯体が好ましく、八面体６配位、平面４配位錯体がより好ましい。また錯体は単核錯体であっても多核錯体であってもよい。また錯体を構成する配位子としては、ＣＮ^-、ＣＯ、ＮＯ₂ ^-、１，１０−フェナントロリン、２，２′−ビピリジン、ＳＯ₃ ^-、エチレンジアミン、ＮＨ₃、ピリジン、Ｈ₂Ｏ、ＮＣＳ^-、ＮＣＯ^-、ＮＯ₃ ^-、ＳＯ₄ ^2-、ＯＨ^-、ＣＯ₃ ^2-、ＳＳＯ₃ ^2-、Ｎ₃ ^-、Ｓ₂ ^-、Ｆ^-、Ｃｌ^-、Ｂｒ^-、Ｉ^-などを用いることができる。ＮＣＳ^-についてはＮ原子、Ｓ原子のどちらで配位するでも用いることができる。
【００９３】
本発明の好ましいドープする金属化合物の具体例として、
Ｋ₄Ｆｅ（ＣＮ）₆、Ｋ₃Ｆｅ（ＣＮ）₆、Ｐｂ（ＮＯ₃）₂、Ｋ₂ＩｒＣｌ₆、Ｋ₃ＩｒＣｌ₆、Ｋ₂ＩｒＢｒ₆、ＩｎＣｌ₃があげられる。
【００９４】
メタルドーパントの、ハロゲン化銀粒子中の濃度分布は、粒子を表面から内部へ少しずつ溶解し、各部分のドーパント含有量を測定することにより求められる。具体例として以下に述べる方法があげられる。
【００９５】
メタルの定量に先立ち、ハロゲン化銀乳剤を以下のように前処理する。まず、乳剤約３０ｍｌに０．２％アクチナーゼ水溶液５０ｍｌを加え、４０℃で３０分間撹拌してゼラチン分解を行なう。この操作を５回繰り返す。遠心分離後、メタノール５０ｍｌで５回、１Ｎ硝酸５０ｍｌで２回，超純水で５回洗浄を繰り返し、遠心分離後ハロゲン化銀のみを分離する。得られたハロゲン化銀の粒子表面部分をアンモニア水溶液あるいはｐＨ調整したアンモニア（アンモニア濃度及びｐＨはハロゲン化銀の種類及び溶解量に応じて変化させる）により溶解する。ハロゲン化銀のうち臭化銀粒子の極表面を溶解する方法としては、ハロゲン化銀２ｇに対し約１０％アンモニア水溶液２０ｍｌを用いて粒子表面より約３％程度の溶解をすることができる。この時、ハロゲン化銀の溶解量はハロゲン化銀の溶解を行なった後のアンモニア水溶液とハロゲン化銀を遠心分離し、得られた上澄み液に存在している銀量を高周波誘導プラズマ質量分析装置（ＩＣＰ−ＭＳ）高周波誘導プラズマ発光分析装置（ＩＣＰ−ＡＥＳ）、あるいは原子吸光にて定量できる。表面溶解後のハロゲン化銀に含まれるメタル量と溶解を行なわないトータルのハロゲン化銀のメタル量の差から、粒子表面約３％に存在するハロゲン化銀１モル当たりのメタル量を求めることができる。メタルの定量方法としては、チオ硫酸アンモニウム水溶液、チオ硫酸ナトリウム水溶液、あるいはシアン化カリウム水溶液に溶解し、マトリックスマッチングしたＩＣＰ−ＭＳ法、ＩＣＰ−ＡＥＳ法、あるいは原子吸光法があげられる。このうち溶剤としてシアン化カリウム、分析装置としてＩＣＰ−ＭＳ（ＦＩＳＯＮ Ｅｌｅｍｅｎｔａｌ Ａｎａｌｙｓｉｓ社製）を用いる場合は、ハロゲン化銀約４０ｍｇを５ｍｌの０．２Ｎシアン化カリウムに溶解後、１０ｐｐｂになるように内標準元素Ｃｓ溶液を添加し、超純水にて１００ｍｌに定容したものを測定試料とする。そしてメタルフリーのハロゲン化銀を用いてマトリックスを合わせた検量線を用いてＩＣＰ−ＭＳにより測定試料中のメタルの定量を行なう。この時、測定試料中の正確な銀量は超純水で１００倍稀釈した測定試料をＩＣＰ−ＡＥＳ、あるいは原子吸光にて定量できる。なお、このような粒子表面の溶解を行なった後、ハロゲン化銀粒子を超純水にて洗浄後、上記と同様な方法で粒子表面の溶解を繰り返すことにより、ハロゲン化銀粒子内部方向のメタル量の定量を行なうことができる。
【００９６】
先に述べた超薄切片作成法と上記メタル定量方法を組み合わせる事によって、本発明の平板粒子の外周領域にドープされたメタルの定量を行うことができる。
【００９７】
本発明の平板粒子のメタルドーパントの好ましい含有量はハロゲン化銀１モル当たり１×１０^-9モル〜１×１０^-4モルであり、更に好ましくは１×１０^-8モル〜１×１０^-5モルである。
【００９８】
本発明の平板粒子において、外周領域に含有するメタルドーパント量／主平面の中心領域に含有するメタルドーパント量の比は、５倍以上であり、好ましくは１０倍以上、更に好ましくは２０倍以上である。
【００９９】
メタルドーパントは、予めハロゲン化銀微粒子乳剤にドープした状態で基盤粒子に添加する事によって、その効果を有効に発現する。このとき、ハロゲン化銀微粒子１モルに対するメタルドーパントの濃度は１×１０^-1モル〜１×１０^-7モルが好ましく、１×１０^-3モル〜１×１０^-5モルが更に好ましい。
【０１００】
メタルドーパントを予めハロゲン化銀微粒子にドープする方法としては、メタルドーパントをハライド溶液に溶解した状態で微粒子形成を行う事が好ましい。
【０１０１】
ハロゲン化銀微粒子のハロゲン組成は、臭化銀、沃化銀、塩化銀、沃臭化銀、塩臭化銀、塩沃臭化銀のいずれでもよいが、基盤粒子と同じハロゲン組成とする事が好ましい。
【０１０２】
メタルドーパントを含有したハロゲン化銀微粒子の基盤粒子への沈着を行う時期は、基盤粒子形成後から化学増感開始前までの間ならどこでもよいが、脱塩工程終了後から化学増感開始前までの間が特に好ましい。基盤乳剤の塩濃度が低い状態で微粒子乳剤を添加する事によって、基盤粒子の活性が最も高い部分に、ハロゲン化銀微粒子はメタルドーパントと共に沈着する。すなわち、本発明の平板粒子のコーナー、エッジを含む外周領域に効率的に沈着させる事ができる。この沈着させるとは、ハロゲン化銀微粒子がそのまま基盤粒子に凝集、吸着するのではなく、ハロゲン化銀微粒子と基盤粒子が共存する反応系内で、ハロゲン化銀微粒子が溶解し、基盤粒子上にハロゲン化銀として再生成させることをいう。すなわち、上記方法で得られた乳剤の一部を取り出し、電子顕微鏡観察を行った際に、ハロゲン化銀微粒子が観察されず、かつ、基盤粒子表面にはエピタキシャル状の突起部分が観察されない事をいう。
【０１０３】
添加するハロゲン化銀微粒子は、基盤粒子１モル当たり１×１０^-7モル〜０．５モルの銀量を添加する事が好ましく、１×１０^-5モル〜１×１０^-1モルの銀量を添加する事が更に好ましい。
【０１０４】
ハロゲン化銀微粒子を沈着させるための物理熟成条件は、３０℃〜７０℃／１０分間〜６０分間の間で任意に選ぶことができる。
【０１０５】
本発明の好ましい態様として、本発明のハロゲン化銀乳剤に含まれる平板粒子の少なくとも一部が粒子内部に還元増感中心を有することがあげられる。
【０１０６】
粒子内部に還元増感中心を有するとは、還元増感によって形成された微小銀核を粒子内部に有することであり、ハロゲン化銀粒子の成長終了以前に還元増感処理を行うことで達成される。
【０１０７】
粒子内部とは、ハロゲン化銀粒子の、粒子最表層以外の部分を指すが、粒子全体の体積で９０％より内側であることが好ましく、７０％より内側がより好ましく、５０％より内側がさらに好ましい。また、該銀核含有層は、後に述べる転位線導入部より、内部に存在することが好ましい。
【０１０８】
還元増感は、ハロゲン化銀乳剤又は粒子成長のための混合溶液に還元剤を添加することによって行われる。あるいは、ハロゲン化銀乳剤又は粒子成長のための混合溶液をｐＡｇ７以下の低ｐＡｇ下で、又はｐＨ７以上の高ｐＨ条件下で熟成又は粒子成長させることによって行なわれる。また、これらの方法を組み合わせて行なうこともできる。好ましい方法は、還元剤を添加する方法である。
【０１０９】
還元剤として好ましいものとして二酸化チオ尿素（ホルムアミジンスルフィン酸）、アスコルビン酸及びその誘導体、第１錫塩が挙げられる。他の適当な還元剤としては、ボラン化合物、ヒドラジン誘導体、シラン化合物、アミン及びポリアミン類及び亜硫酸塩等が挙げられる。添加量は、ハロゲン化銀１モル当たり１０^-2〜１０^-8モルが好ましく、１０^-4〜１０^-6モルがより好ましい。
【０１１０】
低ｐＡｇ熟成を行なうためには、銀塩を添加することができるが、水溶性銀塩が好ましい。水溶性銀塩としては硝酸銀が好ましい。熟成時のｐＡｇは７以下が適当であり、好ましくは６以下、更に好ましくは１〜３である（ここで、ｐＡｇ＝−ｌｏｇ［Ａｇ⁺］である）。
【０１１１】
高ｐＨ熟成は、例えばハロゲン化銀乳剤あるいは粒子成長の混合溶液にアルカリ性化合物を添加することによって行われる。アルカリ性化合物としては、例えば水酸化ナトリウム、水酸化カリウム、炭酸ナトリウム、炭酸カリウム、アンモニア等を用いることができる。ハロゲン化銀形成にアンモニア性硝酸銀を添加する方法においては、アンモニアの効果が低下するため、アンモニアを除くアルカリ性化合物が好ましく用いられる。
【０１１２】
還元増感のための還元増感剤、銀塩、アルカリ性化合物の添加方法としては、ラッシュ添加でもよいし、あるいは一定時間をかけて添加してもよい。この場合には、一定流量で添加してもよいし、関数様に流量を変化させて添加してもよい。また、何回かに分割して必要量を添加してもよい。可溶性銀塩及び／又は可溶性ハロゲン化物の反応容器中への添加に先立ち、反応容器中に存在せしめていてもよいし、あるいは可溶性ハロゲン化物溶液中に混入し、ハロゲン化物とともに添加してもよい。更には、可溶性銀塩、可溶性ハロゲン化物とは別個に添加を行なってもよい。
【０１１３】
本発明のハロゲン化銀乳剤に含まれるハロゲン化銀粒子は、粒子中にカルコゲン化銀核含有層を有することが好ましい。カルコゲン化銀核含有層は、粒子全体の体積で５０％より外側にあることが好ましく、より好ましくは７０％より外側にあることが好ましい。カルコゲン化銀核含有層は粒子表面と接していても、いなくてもよいが、化学増感によって、形成されているカルコゲン化物の化学増感核と、本発明のカルコゲン化銀核含有層に含有されるカルコゲン化銀核は、それ自信が潜像形成中心を形成するか否かという点で明らかに区別される。つまり、本発明のカルコゲン化銀核含有層に含有されるカルコゲン化銀核は、化学増感核よりも、電子捕獲能が低いことが必要である。このような条件を満たすカルコゲン化銀核は、後に述べる方法で形成される。
【０１１４】
該カルコゲン化銀核含有層は、転位線導入部より、外側に存在することが好ましい。
【０１１５】
カルコゲン化銀核は、カルコゲンイオンを放出しうる化合物の添加により形成される。好ましいカルコゲン化銀核は硫化銀核、セレン化銀核、テルル化銀核であり、より好ましくは硫化銀核である。
【０１１６】
カルコゲンイオンを放出しうる化合物として硫化物イオン、セレン化物イオン、テルル化物イオンを放出しうる化合物が好ましく用いられる。
【０１１７】
硫化物イオンを放出しうる化合物としては、チオスルフォン酸化合物、ジスルフィド化合物、チオ硫酸塩、硫化物塩、チオカルバミド系化合物、チオホルムアミド系化合物およびロダニン系化合物を、好ましく用いることができる。
【０１１８】
セレン化物イオンを放出しうる化合物としては、セレン増感剤として知られているものを好ましく用いることができる。具体的には、コロイドセレン金属、イソセレノシアネート類（例えば、アリルイソセレノシアネート等）、セレノ尿素類（例えばＮ，Ｎ−ジメチルセレノ尿素、Ｎ，Ｎ，Ｎ−トリエチルセレノ尿素、Ｎ，Ｎ，Ｎ−トリメチル−Ｎ−ヘプタフルオロセレノ尿素、Ｎ，Ｎ，Ｎ−トリメチル−Ｎ−ヘプタフルオロプロピルカルボニルセレノ尿素、Ｎ，Ｎ，Ｎ−トリメチル−Ｎ−４−ニトロフェニルカルボニルセレノ尿素等）、セレノケトン類（例えば、セレノアセトアミド、Ｎ，Ｎ−ジメチルセレノベンズアミド等）、セレノフォスフェート類（例えばトリ−ｐ−トリセレノフォスフェート等）、セレナイド類（例えば、ジエチルセレナイド、ジエチルジセレナイド、トリエチルフォスフィンセレナイド等）が挙げられる。
【０１１９】
テルル化物イオンを放出しうる化合物としては、テルロ尿素類（例えば、Ｎ，Ｎ−ジメチルテルロ尿素、テトラメチルテルロ尿素、Ｎ−カルボキシエチル−Ｎ，Ｎ−ジメチルテルロ尿素等）、ホスフィンテルリド類（例えば、トリブチルホスフィンテルリド、トリシクロヘキシルホスフィンテルリド、トリイソプロピルホスフィンテルリド等）、テルロアミド類（例えば、テルロアセトアミド、Ｎ，Ｎ−ジメチルテルロベンズアミド等）、テルロケトン類、テルロエステル類、イソテルロシアナート類などが挙げられる。
【０１２０】
カルコゲンイオンを放出しうる化合物として特に好ましいのは、チオスルフォン酸化合物であり、下記式〔１〕〜〔３〕で示されるチオスルフォン酸塩化合物が挙げられる。
【０１２１】
〔１〕Ｒ−ＳＯ₂Ｓ−Ｍ
〔２〕Ｒ−ＳＯ₂Ｓ−Ｒ₁
〔３〕ＲＳＯ₂Ｓ−Ｌｍ−ＳＳＯ₂−Ｒ₂
式中、Ｒ、Ｒ₁及びＲ₂は同じでも異なってもよく、脂肪族基、芳香族基またはヘテロ環基を表し、Ｍは陽イオンを、Ｌは２価の連結基を表し、ｍは０または１である。
【０１２２】
式〔１〕〜〔３〕で示される化合物は、これらの構造から誘導される２価の基を繰り返し単位として含有するポリマーであってもよく、Ｒ、Ｒ₁、Ｒ₂、Ｌが互いに結合して環を形成してもよい。
【０１２３】
式〔１〕〜〔３〕で示されるチオスルホン酸塩化合物を更に詳しく説明する。Ｒ、Ｒ₁、Ｒ₂が脂肪族基の場合、飽和又は不飽和の直鎖、分岐又は環状の脂肪族炭化水素基であり、好ましくは炭素原子数が１〜２２のアルキル基（メチル、エチル、プロピル、ブチル、ペンチル、ヘキシル、オクチル、２−エチルヘキシル、デシル、ドデシル、ヘキサデシル、オクタデシル、シクロヘキシル、イソプロピル、ｔ−ブチル等）、炭素原子数が２〜２２のアルケニル基（アリル、ブテニル等）、及びアルキニル基（プロパルギル、ブチニル等）であり、これらは置換基を有していてもよい。
【０１２４】
Ｒ、Ｒ₁、Ｒ₂が芳香族基の場合、単環又は縮合環の芳香族基を含み、好ましくは炭素原子数が６〜２０のもので、例えばフェニル、ナフチルが挙げられる。これらは、置換基を有してもよい。
【０１２５】
Ｒ、Ｒ₁、Ｒ₂がヘテロ環基の場合、窒素、酸素、硫黄、セレン、テルルから選ばれる元素を少なくとも１つ有し、かつ炭素原子を少なくとも１つ有する３〜１５員環で、好ましくは３〜６員環であり、例えばピロリジン、ピペリジン、ピリジン、テトラヒドロフラン、チオフェン、オキサゾール、チアゾール、イミダゾール、ベンゾチアゾール、ベンズオキサゾール、ベンズイミダゾール、セレナゾール、ベンゾセレナゾール、テトラゾール、トリアゾール、ベンゾトリアゾール、オキサジアゾール、チアジアゾール環が挙げられる。
【０１２６】
Ｒ、Ｒ₁、Ｒ₂の置換基としては、アルキル基（例えば、メチル、エチル、ヘキシル）、アルコキシ基（例えば、メトキシ、エトキシ、オクチルオキシ）、アリール基（例えば、フェニル、ナフチル、トリル）、ヒドロキシ基、ハロゲン原子（例えば、フッ素、塩素、臭素、ヨウ素）、アリールオキシ基（例えば、フェノキシ）、アルキルチオ基（例えばメチルチオ、ブチルチオ）、アリールチオ基（例えば、フェニルチオ）、アシル基（例えば、アセチル、プロピオニル、ブチリル、バレリル）、スルホニル基（例えば、メチルスルホニル、フェニルスルホニル）、アシルアミノ基（例えば、アセチルアミノ、ベンゾイルアミノ）、スルホニルアミノ基（例えば、メタンスルホニルアミノ、ベンゼンスルホニルアミノ）、アシルオキシ基（例えば、アセトキシ、ベンゾキシ）、カルボキシル基、シアノ基、スルホ基、アミノ基、−ＳＯ₂ＳＭ基（Ｍは１価の陽イオンを示す）、−ＳＯ₂Ｒ₁基が挙げられる。
【０１２７】
Ｌで表される２価の連結基としては、Ｃ、Ｎ、Ｓ及びＯから選ばれる少なくとも１種を含む原子又は原子団を挙げることができる。具体的にはアルキレン基、アルケニレン基、アルキニレン基、アリーレン基、−Ｏ−、−Ｓ−、−ＮＨ−、−ＣＯ−、−ＳＯ₂−等の単独又はこれらの組み合わせからなるものである。
【０１２８】
Ｌは好ましくは２価の脂肪族基又は２価の芳香族基である。２価の脂肪族基としては、例えば、
【０１２９】
【化２】

【０１３０】
キシリレン基等が挙げられる。２価の芳香族基としては、例えばフェニレン基、ナフチレン基等が挙げられる。
【０１３１】
これらの置換基は、更にこれまで述べた置換基で置換されていてもよい。
【０１３２】
Ｍとして好ましくは、金属イオン又は有機カチオンである。金属イオンとしては、例えばリチウムイオン、ナトリウムイオン、カリウムイオンが挙げられる。有機カチオンとしては、例えばアンモニウムイオン（アンモニウム、テトラメチルアンモニウム、テトラブチルアンモニウム等）、ホスホニウムイオン（テトラフェニルホスホニウム等）、グアニジル基が挙げられる。
【０１３３】
式〔１〕〜〔３〕で表される化合物がポリマーである場合、その繰り返し単位としては、例えば以下のものが挙げられる。これらのポリマーは、ホモポリマーでもよいし、他の共重合モノマーとのコポリマーでもよい。
【０１３４】
【化３】

【０１３５】
式〔１〕〜〔３〕で表される化合物の具体例は、例えば、特開昭５４−１０１９号、英国特許第９７２，２１１号、Ｊｏｕｒｎａｌ ｏｆ Ｏｒｇａｎｉｃ Ｃｈｅｍｉｓｔｒｙ ｖｏｌ．５３，ｐ．３９６（１９８８）に記載されるものが挙げられる。
【０１３６】
カルコゲン化銀核を形成するための、カルコゲンイオンを放出しうる化合物の添加量は、ハロゲン化銀１モル当たり１０^-2〜１０^-8モルが好ましく、１０^-3〜１０^-6がより好ましい。
【０１３７】
カルコゲン化銀核を形成するための、カルコゲンイオンを放出しうる化合物の添加方法としては、ラッシュ添加でもよいし、あるいは一定時間をかけて添加してもよい。この場合には、一定流量で添加してもよいし、関数様に流量を変化させて添加してもよい。また、何回かに分割して必要量を添加してもよい。カルコゲン化銀核の形成は粒子形成終了までに行うことが必要である。粒子形成後にカルコゲン化銀核の形成を行っても行わなくても良いが、粒子形成後に形成されたカルコゲン化銀核は、化学増感過程で形成する化学増感核の一部として取り込まれ、実質的に本発明の効果には寄与しない。同様に、粒子内部に化学増感をおこなった場合も、化学増感と同一面に形成するカルコゲン化銀核は、実質的に本発明の効果には寄与しない。
【０１３８】
本発明のハロゲン化銀乳剤は、その製造工程中に、上記カルコゲンイオンを放出しうる化合物に含まれる銀に対する酸化剤以外にも、銀に対する酸化剤を添加する事ができる。銀に対する酸化剤とは、金属銀に作用して銀イオンに変換せしめる作用を有する化合物を言う。
【０１３９】
銀に対する酸化剤は、無機物であっても、有機物であってもよい。無機の酸化剤としては、オゾン、過酸化水素及びその付加物（例えば、ＮａＢＯ₂・Ｈ₂Ｏ₂・３Ｈ₂Ｏ、２ＮａＣＯ₃・３Ｈ₂Ｏ₂、Ｎａ₄Ｐ₂Ｏ₇・２Ｈ₂Ｏ₂、２Ｎａ₂ＳＯ₄・Ｈ₂Ｏ₂・Ｈ₂Ｏ）、ペルオキシ酸塩（例えば、Ｋ₂Ｓ₂Ｏ₈、Ｋ₂Ｃ₂Ｏ₆、Ｋ₄Ｐ₂Ｏ₈）、ペルオキシ錯体化合物（例えば、Ｋ₂［Ｔｉ（Ｏ₂）Ｃ₂Ｏ₄］・３Ｈ₂Ｏ、４Ｋ₂ＳＯ₄・Ｔｉ（Ｏ₂）ＯＨ・ＳＯ₄・２Ｈ₂Ｏ、Ｎａ₃［ＶＯ（Ｏ₂）（Ｃ₂Ｏ₄）₂・６Ｈ₂Ｏ］）、過マンガン酸塩（例えばＫＭｎＯ₄）、クロム酸塩（例えばＫ₂Ｃｒ₂Ｏ₇）等の酸素酸塩、沃度や臭素等のハロゲン元素、過ハロゲン酸塩（例えば、過沃素酸カリウム）、高原子価の金属の塩（例えば、ヘキサシアノ第二鉄酸カリウム）及びチオスルホン酸塩等がある。又、有機の酸化剤としては、ｐ−キノン等のキノン類、過酢酸や過安息香酸等の有機過酸化物、活性ハロゲンを放出する化合物（例えば、Ｎ−ブロムサクシイミド、クロラミンＴ、クロラミンＢ）が挙げられる。
【０１４０】
銀に対する酸化剤としては、ハロゲン元素が好ましく用いられ、沃素が特に好ましく用いられる。本発明における銀に対する酸化剤の好ましい添加量は、銀１ｍｏｌあたり、１×１０^-5ｍｏｌ以上１×１０^-2ｍｏｌ以下であり、より好ましくはＩ原子にして銀１ｍｏｌあたり、１×１０^-4ｍｏｌ以上１×１０^-3ｍｏｌ以下であり、さらに好ましくはＩ原子にして銀１ｍｏｌあたり、５×１０^-5ｍｏｌ以上５×１０^-4ｍｏｌ以下である。
【０１４１】
本発明のハロゲン化銀乳剤は、単独で乳剤層に用いる以外に、本発明の効果を損なわない範囲で、他のハロゲン化銀乳剤と混合して用いることができる。同一乳剤層内で、他のハロゲン化銀乳剤と混合して用いる場合、平均粒径の異なる本発明の乳剤を複数混合して用いることは、好ましい使用形態である。
【０１４２】
本発明乳剤の感光材料中での、好ましい使用形態の例を以下に記す。
【０１４３】
・同一感色性で感度の異なる２つ以上の乳剤層に、本発明の乳剤を用いる。その場合、各層に含まれる本発明の乳剤の平均粒径が異なっていることが好ましい。
【０１４４】
・感色性が異なり、感度が近似の２つ以上の乳剤層に、本発明の乳剤を用いる。その場合、各層に含まれる本発明の乳剤の平均粒径が近似であることが好ましく、各層に同一の本発明乳剤を用いることはより好ましい。
【０１４５】
・すべての乳剤層に本発明の乳剤を用いる。
【０１４６】
本発明のハロゲン化銀乳剤は、常法により化学増感することができる。すなわち、硫黄増感、セレン増感、金その他の貴金属化合物を用いる貴金属増感法などを単独でまたは組み合わせて用いることができる。
【０１４７】
本発明のハロゲン化銀乳剤は、写真業界において増感色素として知られている色素を用いて所望の波長域に光学的に増感できる。増感色素は、単独で用いてもよいが２種類以上を組み合わせて用いても良い。増感色素と共にそれ自身分光増感作用をもたない色素、あるいは可視光を実質的に吸収しない化合物であって、増感色素の増感作用を強める強色増感剤を乳剤中に含有させても良い。
【０１４８】
本発明のハロゲン化銀乳剤には、カブリ防止剤、安定剤などを加えることができる。バインダーとしては、ゼラチンを用いるのが有利である。乳剤層、その他の親水性コロイド層は、硬膜することができ、また、可塑剤、水不溶性または可溶性合成ポリマーの分散物（ラテックス）を含有させることができる。
【０１４９】
本発明のハロゲン化銀写真乳剤は、写真感光材料に用いる事ができ、一般用および映画用カラーフィルム、カラーペーパー、カラーリバーサルフィルム、カラーリバーサルペーパーなどのカラー写真感光材料に好ましく用いることができる。
【０１５０】
カラー写真感光材料の乳剤層にはカプラーが用いられる。さらに色補正の効果を有している競合カプラーおよび現像主薬の酸化体とのカップリングによって現像促進剤、現像剤、ハロゲン化銀溶剤、調色剤、硬膜剤、カブリ剤、カブリ防止剤、化学増感剤、分光増感剤および減感剤のような写真的に有用なフラグメントを放出する化合物を用いることができる。
【０１５１】
感光材料には、フィルター層、ハレーション防止層、イラジュエーション防止層等の補助層を設けることができる。これらの層中および／または乳剤層中には現像処理中に感光材料から流出するか、もしくは漂白される染料が含有されても良い。
【０１５２】
感光材料には、マット剤、滑剤、画像安定剤、ホルマリンスカベンジャー、紫外線吸収剤、蛍光増白剤、界面活性剤、現像促進剤や現像遅延剤を添加できる。
【０１５３】
支持体としては、ポリエチレン等をラミネートした紙、ポリエチレンテレフタレートフィルム、バライタ紙、三酢酸セルロース等を用いることができる。
【０１５４】
【実施例】
以下に、本発明を実施例により詳細に説明するが、本発明はこれらに限定されるものではない。
【０１５５】
実施例１
（１）比較乳剤Ｅｍ−１の調製
《核形成工程》
反応容器内の下記反応母液（Ｇｒ−１）を３０℃に保ち、特開昭６２−１６０１２８号公報記載の混合攪拌装置を用いて攪拌回転数４００回転／分で攪拌しながら、１Ｎの硫酸を用いてｐＨを１．９６に調整した。その後ダブルジェット法を用いて（Ｓ−１）液と（Ｈ−１）液のそれぞれ、１７８ｍｌづつを、一定の流量で１分間で添加し核形成を行った。
【０１５６】
（Ｇｒ−１）
アルカリ処理不活性ゼラチン（平均分子量１０万） ４０．５０ｇ
臭化カリウム １２．４０ｇ
蒸留水で１６．２Ｌに仕上げる
（Ｓ−１）
硝酸銀 ８６２．５ｇ
蒸留水で４．０６Ｌに仕上げる
（Ｈ−１）
臭化カリウム ６０４．５ｇ
蒸留水で４．０６Ｌに仕上げる。
【０１５７】
《熟成工程》
上記核形成工程終了後に（Ｇ−１）液を加え、３０分間を要して６０℃に昇温した。この間、反応容器内の乳剤の銀電位（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２Ｎの臭化カリウム溶液を用いて６ｍＶに制御した。続いて、アンモニア水溶液を加えてｐＨを９．３に調整し、更に７分間保持した後、酢酸水溶液を用いてｐＨを６．１に調整した。この間の銀電位を２Ｎの臭化カリウム溶液を用いて６ｍＶに制御した。
【０１５８】

蒸留水で４．２２Ｌに仕上げる。
【０１５９】
《粒子成長工程》
熟成工程終了後、続いてダブルジェット法を用いて前記（Ｓ−１）液と（Ｈ−１）液の残りを、流量を加速しながら（終了時と開始時の添加流量の比が約１２倍）、３７分間で添加した。添加終了後に（Ｇ−２）液を加え、攪拌回転数を５５０回転／分に調整した後、引き続いて（Ｓ−２）液のうち２．１１Ｌと（Ｈ−２）液を、流量を加速しながら（終了時と開始時の添加流量の比が約２倍）、４０分間で添加した。この間乳剤の銀電位を２Ｎの臭化カリウム溶液を用いて６ｍＶに制御した。上記添加終了後に、反応容器内の乳剤温度を１５分間を要して４０℃に降温した。その後、３Ｎの臭化カリウム溶液を用いて反応容器内の銀電位を−３９ｍＶ（ｐＢｒ１．２９）に調整し、続いて（Ｋ−１）液を４０７．５ｇ加えた後、（Ｓ−２）液の残りと（Ｈ−３）液を流量を加速しながら（終了時と開始時の添加流量の比が約１．２倍）、２５分間で添加した。
【０１６０】
（Ｓ−２）
硝酸銀 ２１３７．５ｇ
蒸留水で３．６０Ｌに仕上げる
（Ｈ−２）
臭化カリウム ８５９．５ｇ
沃化カリウム ２４．４５ｇ
蒸留水で２．１１Ｌに仕上げる
（Ｈ−３）
臭化カリウム ６２０．６ｇ
蒸留水で１．４９Ｌに仕上げる
（Ｇ−２）
オセインゼラチン ２８４．９ｇ
化合物ＥＯ（１０％エタノール溶液） ７．７５ｍｌ
蒸留水で１．９３Ｌに仕上げる
（Ｋ−１）
沃化カリウム ３８．１ｇ
蒸留水で１８３．６ｍｌに仕上げる。
【０１６１】
上記粒子成長終了後に、特開平５−７２６５８号に記載の方法に従い脱塩処理を施し、その後ゼラチンを加え分散し、４０℃にてｐＨを５．８０、ｐＡｇを８．０５に調整した。このようにして得られた乳剤をＥｍ−１とする。
【０１６２】
得られた乳剤粒子の電子顕微鏡写真から、投影面積の円換算直径の平均値から求めた粒径１．５０μｍ、アスペクト比７．４（全投影面積の５０％）、粒径分布の変動係数１５．０％、粒子厚さの変動係数２１．２％の平板粒子であることが確認された。
【０１６３】
（２）比較乳剤Ｅｍ−２の調製
Ｅｍ−１の調製において、《粒子成長工程》の降温以降の温度を５５℃とし、引き続きＥＡｇ調整値を−３０ｍＶ（ｐＢｒ１．２９）とした以外は、Ｅｍ−１と同様にして、比較乳剤Ｅｍ−２を調製した。電子顕微鏡観察の結果、Ｅｍ−２はＥｍ−１とほぼ同様な粒径、アスペクト比、粒径分布の変動係数、粒子厚さの変動係数の粒子よりなることが確認された。
【０１６４】
（３）比較乳剤Ｅｍ−３の調製
Ｅｍ−１の調製において、《粒子成長工程》を以下の様にした以外は、Ｅｍ−１と同様にして、比較乳剤Ｅｍ−３を調製した。電子顕微鏡観察の結果、Ｅｍ−３はＥｍ−１とほぼ同様な粒径、アスペクト比、粒径分布の変動係数、粒子厚さの変動係数の粒子よりなることが確認された。Ｅｍ−３の粒子内の沃化銀含有率の緩慢連続変化状況を表すグラフを図２に示した。図２は、Ｅｍ−３の、粒子中心部から粒子端部までの各点での沃化銀含有率を示したものである。明らかに粒子の中心から６４０ｎｍ〜６９０ｎｍでの沃化銀含有率の変化は急激であり、０．２ｍｏｌ％／ｎｍ以上で、本発明の沃化銀含有率の緩慢連続変化の定義から逸脱したハロゲン化銀粒子である。
【０１６５】
《粒子成長工程》
熟成工程終了後、続いてダブルジェット法を用いて前記（Ｓ−１）液と（Ｈ−１）液の残りを、流量を加速しながら（終了時と開始時の添加流量の比が約１２倍）、３７分間で添加した。添加終了後に（Ｇ−２）液を加え、攪拌回転数を５５０回転／分に調整した後、引き続いて（Ｓ−３）液のうち２．１１Ｌと（Ｈ−２）液を、流量を加速しながら（終了時と開始時の添加流量の比が約２倍）、４０分間で添加した。この間乳剤の銀電位を２Ｎの臭化カリウム溶液を用いて６ｍＶに制御した。上記添加終了後に、反応容器内の乳剤温度を１５分間を要して４０℃に降温した。その後、３Ｎの臭化カリウム溶液を用いて反応容器内の銀電位を−４０ｍＶ（ｐＢｒ１．２９）に調整し、続いて（Ｆ−１）液を４０７．５ｇ加えた後、（Ｓ−３）液の残りと（Ｈ−４）液を流量を加速しながら（終了時と開始時の添加流量の比が約１．２倍）、２５分間で添加した。
【０１６６】
（Ｓ−３）
硝酸銀 ２０９８．５ｇ
蒸留水で３．５３Ｌに仕上げる
（Ｈ−２）
臭化カリウム ８５９．５ｇ
沃化カリウム ２４．４５ｇ
蒸留水で２．１１Ｌに仕上げる
（Ｈ−４）
臭化カリウム ５９１．５ｇ
蒸留水で１．４２Ｌに仕上げる
（Ｇ−２）
オセインゼラチン ２８４．９ｇ
化合物ＥＯ（１０％エタノール溶液） ７．７５ｍｌ
蒸留水で１．９３Ｌに仕上げる
（Ｆ−１）
３重量％のゼラチンと、沃化銀粒子（平均粒径０．０５μｍ）からなる
微粒子乳剤（＊） ４０７．５ｇ
＊調製法は以下の通り：０．０６モルの沃化カリウムを含む６．０重量％のゼラチン溶液５０００ｍｌに、７．０６モルの硝酸銀と、７．０６モルの沃化カリウムを含む水溶液、それぞれ２０００ｍｌを、１０分間かけて添加した。微粒子形成中のｐＨは硝酸を用いて２．０に、温度は４０℃に制御した。粒子形成後に、炭酸ナトリウム水溶液を用いてｐＨを６．０に調整した。仕上がり重量は１２．５３ｋｇであった。
【０１６７】
（４）比較乳剤Ｅｍ−４の調製
Ｅｍ−３の調製において、《粒子成長工程》の降温以降の温度を５５℃とし、引き続くＥＡｇ調整値を−３０ｍＶ（ｐＢｒ１．２９）とした以外は、Ｅｍ−３と同様にして、比較乳剤Ｅｍ−４を調製した。電子顕微鏡観察の結果、Ｅｍ−４はＥｍ−１とほぼ同様な粒径、アスペクト比、粒径分布の変動係数、粒子厚さの変動係数の粒子よりなることが確認された。
【０１６８】
（５）本発明乳剤Ｅｍ−５の調製
Ｅｍ−１の調製において、《粒子成長工程》を以下の様にした以外は、Ｅｍ−１と同様にして、本発明乳剤Ｅｍ−５を調製した。電子顕微鏡観察の結果、Ｅｍ−５はＥｍ−１とほぼ同様な粒径、アスペクト比、粒径分布の変動係数、粒子厚さの変動係数の粒子よりなることが確認された。Ｅｍ−５の粒子内の沃化銀含有率の緩慢連続変化状況を表すグラフを図３に示した。図３は、Ｅｍ−５の、粒子中心部から粒子端部までの各点での沃化銀含有率を示したものである。明らかに粒子のどの領域でも沃化銀含有率の変化は小さく、本発明の沃化銀含有率の緩慢連続変化の定義０．０３ｍｏｌ％／ｎｍを満足するハロゲン化銀粒子である。
【０１６９】
《粒子成長工程》
熟成工程終了後、続いてダブルジェット法を用いて前記（Ｓ−１）液と（Ｈ−１）液の残りを、流量を加速しながら（終了時と開始時の添加流量の比が約１２倍）、３７分間で添加した。添加終了後に（Ｇ−２）液を加え、攪拌回転数を５５０回転／分に調整した後、引き続いて（Ｓ−２）液のうち２．１１Ｌと（Ｈ−２）液を、流量を加速しながら（終了時と開始時の添加流量の比が約２倍）、４０分間で添加した。この間乳剤の銀電位を２Ｎの臭化カリウム溶液を用いて６ｍＶに制御した。上記添加終了後に、反応容器内の乳剤温度を１５分間を要して４０℃に降温した。その後、沃素イオン放出剤を含む溶液（Ｚ−１）と求核剤を含む溶液（ＳＳ−１）を添加し、水酸化カリウム水溶液を用いて、ｐＨ９．３に調整した。４分間熟成しつつ、沃素イオン放出反応をおこなったのち、酢酸溶液を用いて、ｐＨを５．０に調整した。その後、３Ｎの臭化カリウム溶液を用いて反応容器内の銀電位を−４０ｍＶ（ｐＢｒ１．２９）に調整し、続いて（Ｆ−１）液を４０７．５ｇ加えた後、（Ｓ−２）液の残りと（Ｈ−３）液を流量を加速しながら（終了時と開始時の添加流量の比が約１．２倍）、２５分間で添加した。
【０１７０】
（Ｓ−２）
硝酸銀 ２１３７．５ｇ
蒸留水で３．６０Ｌに仕上げる
（Ｈ−２）
臭化カリウム ８５９．５ｇ
沃化カリウム ２４．４５ｇ
蒸留水で２．１１Ｌに仕上げる
（Ｈ−３）
臭化カリウム ６２０．６ｇ
蒸留水で１．４９Ｌに仕上げる
（Ｇ−２）
オセインゼラチン ２８４．９ｇ
化合物ＥＯ（１０％エタノール溶液） ７．７５ｍｌ
蒸留水で１．９３Ｌに仕上げる
（Ｚ−１）
ｐ−ヨードアセトアミドベンゼンスルホン酸ナトリウム ８３．４ｇ
蒸留水で１．０Ｌに仕上げる
（ＳＳ−１）
亜硫酸ナトリウム ２８．９ｇ
蒸留水で０．３Ｌに仕上げる。
【０１７１】
（６）比較乳剤Ｅｍ−６の調製
Ｅｍ−５の調製において、《粒子成長工程》の降温以降の温度を５５℃とし、沃素イオン放出反応に引き続くＥＡｇ調整値を−３０ｍＶ（ｐＢｒ１．２９）とした以外は、Ｅｍ−５と同様にして、比較乳剤Ｅｍ−６を調製した。電子顕微鏡観察の結果、Ｅｍ−６はＥｍ−１とほぼ同様な粒径、アスペクト比、粒径分布の変動係数、粒子厚さの変動係数の粒子よりなることが確認された。
【０１７２】
（７）本発明乳剤Ｅｍ−７の調製
Ｅｍ−５の調製において、《粒子成長工程》の（Ｚ−１）液、（ＳＳ−１）液の代わりに、それぞれ（Ｚ−２）液、（ＳＳ−２）液を用いる以外は、Ｅｍ−５と同様にして本発明乳剤Ｅｍ−７を調製した。電子顕微鏡観察の結果、Ｅｍ−７はＥｍ−１とほぼ同様な粒径、アスペクト比、粒径分布の変動係数、粒子厚さの変動係数の粒子よりなることが確認された。
【０１７３】
（Ｚ−２）
ｐ−ヨードアセトアミドベンゼンスルホン酸ナトリウム ５７．７ｇ
蒸留水で１．０Ｌに仕上げる
（ＳＳ−２）
亜硫酸ナトリウム ２０．０ｇ
蒸留水で０．３Ｌに仕上げる。
【０１７４】
（８）比較乳剤Ｅｍ−８の調製
Ｅｍ−１の調製において、《粒子成長工程》の（Ｋ−１）液添加を行わない以外は、Ｅｍ−１と同様にして、比較乳剤Ｅｍ−８を調製した。電子顕微鏡観察の結果、Ｅｍ−８はＥｍ−１とほぼ同様な粒径、アスペクト比、粒径分布の変動係数、粒子厚さの変動係数の粒子よりなることが確認された。
【０１７５】
（９）各乳剤の化学増感／分光増感処理
前記各乳剤Ｅｍ−１〜Ｅｍ−８を５２℃に保持しながら、下記増感色素ＳＳＤ−１、ＳＳＤ−２、ＳＳＤ−３を加えた。２０分間熟成した後、チオ硫酸ナトリウムを加え、さらに塩化金酸とチオシアン酸カリウムを添加した。各乳剤ごとに最適な感度−カブリが得られるように熟成を行った後、１−フェニル−５−メルカプトテトラゾールと４−ヒドロキシ−６−メチル−１，３，３ａ，７−テトラザインデンを加えて安定化した。各乳剤に対する増感色素、増感剤、安定剤の添加量と熟成時間は、１／２００秒露光時の感度−カブリ関係が最適になるように設定した。
【０１７６】
（１０）塗布試料の作成／評価
増感処理を施したＥｍ−１〜Ｅｍ−８の各乳剤に、下記のカプラーＭＣＰ−１を酢酸エチル、トリクレジルフォスフェートに溶解しゼラチンを含む水溶液中に乳化分散した分散物、延展剤、及び硬膜剤等の一般的な写真添加剤を加えて塗布液を調製し、下塗りを施した三酢酸セルロースフィルム支持体上に常法に従い塗布し乾燥してカラー感光材料試料Ｎｏ．１０１〜Ｎｏ．１０８を作製した。
【０１７７】
【化４】

【０１７８】
これらの試料作製直後に各試料に対して、色温度５４００°Ｋの光源を用い東芝ガラスフィルター（Ｙ−４８）を通してウェッジ露光を行い、下記の処理工程に従って現像処理を行った。
【０１７９】

【０１８０】
発色現像液、漂白液、定着液、安定液及びその補充液は、以下のものを使用した。
【０１８１】

水を加えて１リットルとし、水酸化カリウム又は２０％硫酸を用いて発色現像液はｐＨ１０．０６に、補充液はｐＨ１０．１８に調整する。
【０１８２】

水を加えて１リットルとし、アンモニア水又は氷酢酸を用いて漂白液はｐＨ４．４に、補充液はｐＨ４．０に調整する。
【０１８３】

アンモニア水又は氷酢酸を用いて定着液はｐＨ６．２に、補充液はｐＨ６．５に調整後、水を加えて１リットルとする。
【０１８４】

水を加えて１リットルとした後、アンモニア水又は５０％硫酸を用いてｐＨ８．５に調整する。
【０１８５】
得られた試料の感度、カブリを緑色光を用いて測定した。測定方法及び条件を以下に示す。
【０１８６】
相対感度は、各試料において、最小濃度（Ｄｍｉｎ）＋０．２の濃度を与える露光量の逆数を感度として求め、試料Ｎｏ．１０８の感度を１００とする相対値で示した。相対感度の値が大きいほど感度が高く好ましいことを意味する。
【０１８７】
被圧によるカブリ増加は、未露光部における荷重が加えられた部分の濃度増加量を測定し、試料Ｎｏ．１０８の濃度増加量を１００とする相対値（ΔＤｐ１）で示した（この値が小さいほど被圧によるカブリ増加が小さく圧力耐性に優れることを意味する）。被圧による感度低下は、（Ｄｍａｘ−Ｄｍｉｎ）／２の濃度部における荷重が加えられた部分の濃度低下量を測定し、試料Ｎｏ．１０８の濃度低下量を１００とする相対値（ΔＤｐ２）で示した（この値が小さいほど被圧による感度低下が小さく圧力耐性に優れることを意味する）。
【０１８８】
現像処理適性の評価として、処理工程における発色現像処理の時間を２分５０秒に短縮し、３分１５秒現像をおこなったものからの感度の劣化幅を、試料Ｎｏ．１０８の値を１００とした相対値として、ΔＳであらわした。
【０１８９】
乳剤特性評価の結果を、表１，２に示す。
【０１９０】
（１１）転位線比率と沃化銀輪郭の観察／沃化銀含有率変化の測定
各乳剤を超純水で５倍に希釈後、遠心分離し、沈殿を超純水中に再分散した。親水化処理をおこなったカーボン支持膜付き２００メッシュに滴下し、余分な分散液をスピンコーターで除去した。透過型電子顕微鏡ＴＥＭ２０００ＦＸを用いて、加速電圧２００ｋＶ、測定温度−１３０℃、直接倍率×８０００〜×１００００で、粒子７００個程度の撮影を行った後、フリンジ部に粒子１個あたり、３０本以上転位線を有する粒子と、沃化銀輪郭を有する粒子の全粒子投影面積に占める割合を求めた。沃化銀輪郭をもつ平板状粒子の電子顕微鏡写真の１例を図１に示す。
【０１９１】
また、同じ試料と装置を用いて、ＥＰＭＡ（ＴＥＭ−ＥＤＳ法）による粒子中心から、粒子端部にかけての沃化銀含有率変化の測定を行った。加速電圧２００ｋＶ，測定温度−１３０℃，測定スポット径２０ｎｍ、積算時間５０秒で、粒子中心から粒子端部までの直線上に、１６点の測定を行い、２００個の粒子に対して、沃化銀含有率変化を測定し、変化率が−０．０３ｍｏｌ％／ｎｍ〜＋０．０３ｍｏｌ％／ｎｍである粒子の全粒子投影面積に占める割合を求めた。結果を表１，２に示す。
【０１９２】
【表１】

【０１９３】
【表２】

【０１９４】
実施例２
（１）本発明乳剤Ｅｍ−９の調製
乳剤Ｅｍ−７の調製において、熟成工程を以下のように変更する以外はＥｍ−７と同様にして、本発明乳剤Ｅｍ−９を調製した。
【０１９５】
《熟成工程》
上記核形成工程終了後に（Ｇ−１）液を加え、３０分間を要して６０℃に昇温した。この間、反応容器内の乳剤の銀電位（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２Ｎの臭化カリウム溶液を用いて６ｍＶに制御した。そのまま１５分間攪拌を続けた後、水酸化カリウムを用いてｐＨを６．１に調整した。この間の銀電位を２Ｎの臭化カリウム溶液を用いて６ｍＶに制御した。
【０１９６】
得られた乳剤粒子の電子顕微鏡写真から、投影面積の円換算直径の平均値から求めた粒径１．５３μｍ、アスペクト比７．３（全投影面積の５０％）、粒径分布の変動係数２８．０％、粒子厚さ分布の変動係数３７．４％の平板粒子であることが確認された。転位線粒子比率、沃化銀含有率緩慢連続変化粒子比率、沃化銀輪郭粒子比率はほそれぞれ、７６％、９１％、９％であった。
【０１９７】
（２）乳剤の評価
実施例１の（９）以降と同様にして、Ｅｍ−９を用いた試料１０９を作製し、実施例１と同様の評価を行った。結果を表３に示す。本発明の効果は粒径分布と厚み分布の狭い乳剤で顕著であることがわかる。
【０１９８】
実施例３
（１）本発明乳剤Ｅｍ−１０の調製
乳剤Ｅｍ−７の調製において、粒子成長工程で、（Ｓ−１）液の添加終了後に、（Ｒ−１）液をラッシュ添加し、４０℃に降温する前に、（Ｔ−１）液をラッシュ添加してから、降温を始めた以外はＥｍ−７と同様にして、本発明乳剤Ｅｍ−１０を調製した。得られた乳剤粒子の電子顕微鏡写真から、Ｅｍ−１とほぼ同様な粒子であることが確認された。
【０１９９】
（Ｒ−１）
二酸化チオ尿素 ２６．６ｍｇ
蒸留水 ４６．６ｍｌ
（Ｔ−１）
エタンチオスルフォン酸ナトリウム ８８０．１ｍｇ
蒸留水２９３．４ｍｌ。
【０２００】
（２）本発明乳剤Ｅｍ−１１の調製
Ｅｍ−１０と同様にして粒子成長を行い、脱塩を行ったのち、ゼラチンを加え分散して、乳剤温度を５０℃に調整して、（Ｆ−２）液を添加し、２０分間熟成した。その後、４０℃に降温してｐＨを５．８０、ｐＡｇを８．０６に調整した。このようにして得られた乳剤を本発明乳剤Ｅｍ−１１とする。
【０２０１】
（Ｆ−２）
Ｋ₂ＩｒＣｌ₆をドープした臭化銀粒子（平均粒径０．０５μｍ）からなる
微粒子乳剤（＊） ４．７０ｇ
＊微粒子乳剤Ｆ−２の調製法は以下の通り：０．０６モルの臭化カリウムを含む６．０重量％のゼラチン溶液５０００ｍｌに、７．０６モルの硝酸銀を含む水溶液２０００ｍｌと、７．０６モルの臭化カリウム及び４．４×１０^-3モルのＫ₂ＩｒＣｌ₆を含む水溶液２０００ｍｌを、１０分間かけて添加した。微粒子形成中のｐＨは硝酸を用いて２．０に、温度は４０℃に制御した。粒子形成後に、炭酸ナトリウム水溶液を用いてｐＨを６．０に調整した。仕上がり重量は１２．５３ｋｇであった。
【０２０２】
（３）比較乳剤Ｅｍ−１２の調製
乳剤Ｅｍ−１の調製において、Ｅｍ−１０と同様に、粒子成長工程で、（Ｓ−１）液の添加終了後に、（Ｒ−１）液をラッシュ添加し、４０℃に降温する前に、（Ｔ−１）液をラッシュ添加してから、降温を始めた以外はＥｍ−１と同様にして、比較乳剤Ｅｍ−１２を調製した。得られた乳剤粒子の電子顕微鏡写真から、Ｅｍ−１とほぼ同様な粒子であることが確認された。
【０２０３】
（４）比較乳剤Ｅｍ−１３の調製
Ｅｍ−１２と同様にして粒子成長を行い、脱塩を行ったのち、ゼラチンを加え分散して、乳剤温度を５０℃に調整して、（Ｆ−２）液を添加し、２０分間熟成した。その後、４０℃に降温してｐＨを５．８０、ｐＡｇを８．０６に調整した。このようにして得られた乳剤を比較乳剤Ｅｍ−１３とする。なお、Ｅｍ−１０〜１３はいずれも、粒径、アスペクト比、粒径分布の変動係数、粒子厚さの変動係数がＥｍ−１と同様であった。
【０２０４】
（５）乳剤の評価
実施例１の（９）以降と同様にして、Ｅｍ−１０〜１３を用いた試料１１０〜１１３を作製し、実施例１と同様の評価を行った。結果を表３に示す。本発明の乳剤は還元増感、メタルドープと相乗効果を有することがわかる。
【０２０５】
【表３】

【０２０６】
実施例４
下引き処理を施したトリアセチルセルロースフィルム支持体上に下記に示すような組成の各層を順次支持体側から形成した。高感度緑感色層に化学増感／分光増感を施したＥｍ−７を用いて、多層カラー写真感光材料４０７を作成した。
【０２０７】
添加量は１ｍ²当たりのグラム数で表す。但し、ハロゲン化銀とコロイド銀は銀の量に換算し、増感色素（ＳＤで示す）は銀１モル当たりのモル数で示した。
【０２０８】
第１層（ハレーション防止層）
黒色コロイド銀 ０．１６
ＵＶ−１ ０．３
ＣＭ−１ ０．１２３
ＣＣ−１ ０．０４４
ＯＩＬ−１ ０．１６７
ゼラチン １．３３
第２層（中間層）
ＡＳ−１ ０．１６０
ＯＩＬ−１ ０．２０
ゼラチン ０．６９
第３層（低感度赤感色性層）
沃臭化銀ａ ０．２０
沃臭化銀ｂ ０．２９
ＳＤ−１ ２．３７×１０^-5
ＳＤ−２ １．２×１０^-4
ＳＤ−３ ２．４×１０^-4
ＳＤ−４ ２．４×１０^-6
Ｃ−１ ０．３２
ＣＣ−１ ０．０３８
ＯＩＬ−２ ０．２８
ＡＳ−２ ０．００２
ゼラチン ０．７３
第４層（中感度赤感色性層）
沃臭化銀ｃ ０．１０
沃臭化銀ｄ ０．８６
ＳＤ−１ ４．５×１０^-5
ＳＤ−２ ２．３×１０^-4
ＳＤ−３ ４．５×１０^-4
Ｃ−２ ０．５２
ＣＣ−１ ０．０６
ＤＩ−１ ０．０４７
ＯＩＬ−２ ０．４６
ＡＳ−２ ０．００４
ゼラチン １．３０
第５層（高感度赤感色性層）
沃臭化銀ｃ ０．１３
沃臭化銀ｄ １．１８
ＳＤ−１ ３．０×１０^-5
ＳＤ−２ １．５×１０^-4
ＳＤ−３ ３．０×１０^-4
Ｃ−２ ０．０４７
Ｃ−３ ０．０９
ＣＣ−１ ０．０３６
ＤＩ−１ ０．０２４
ＯＩＬ−２ ０．２７
ＡＳ−２ ０．００６
ゼラチン １．２８
第６層（中間層）
ＯＩＬ−１ ０．２９
ＡＳ−１ ０．２３
ゼラチン １．００
第７層（低感度緑感色性層）
沃臭化銀ａ ０．１９
沃臭化銀ｂ ０．０６２
ＳＤ−４ ３．６×１０^-4
ＳＤ−５ ３．６×１０^-4
Ｍ−１ ０．１８
ＣＭ−１ ０．０３３
ＯＩＬ−１ ０．２２
ＡＳ−２ ０．００２
ＡＳ−３ ０．０５
ゼラチン ０．６１
第８層（中間層）
ＯＩＬ−１ ０．２６
ＡＳ−１ ０．０５４
ゼラチン ０．８０
第９層（中感度緑感色性層）
沃臭化銀ｅ ０．５４
沃臭化銀ｆ ０．５４
ＳＤ−６ ３．７×１０^-4
ＳＤ−７ ７．４×１０^-5
ＳＤ−８ ５．０×１０^-5
Ｍ−１ ０．１７
Ｍ−２ ０．３３
ＣＭ−１ ０．０２４
ＣＭ−２ ０．０２９
ＤＩ−２ ０．０２４
ＤＩ−３ ０．００５
ＯＩＬ−１ ０．７３
ＡＳ−３ ０．０３５
ＡＳ−２ ０．００３
ゼラチン １．８０
第１０層（高感度緑感色性層）
Ｅｍ−７ １．１９
Ｍ−１ ０．０６５
ＣＭ−２ ０．０２６
ＣＭ−１ ０．０２２
ＤＩ−３ ０．００３
ＤＩ−２ ０．００３
ＯＩＬ−１ ０．１９
ＯＩＬ−２ ０．４３
ＡＳ−３ ０．０１７
ＡＳ−２ ０．０１４
ゼラチン １．２３
第１１層（イエローフィルター層）
黄色コロイド銀 ０．０５
ＯＩＬ−１ ０．１８
ＡＳ−１ ０．１６
ゼラチン １．００
第１２層（低感度青感色性層）
沃臭化銀ｂ ０．２２
沃臭化銀ａ ０．０８
沃臭化銀ｇ ０．０９
ＳＤ−９ ６．５×１０^-4
ＳＤ−１０ ２．５×１０^-4
Ｙ−１ ０．７７
ＤＩ−４ ０．０１７
ＯＩＬ−１ ０．３１
ＡＳ−２ ０．００２
ゼラチン １．２９
第１３層（高感度青感色性層）
沃臭化銀ｇ ０．４１
沃臭化銀ｈ ０．６１
ＳＤ−９ ４．４×１０^-4
ＳＤ−１０ １．５×１０^-4
Ｙ−１ ０．２３
ＯＩＬ−１ ０．１０
ＡＳ−２ ０．００４
ゼラチン １．２０
第１４層（第１保護層）
沃臭化銀ｉ ０．３０
ＵＶ−１ ０．０５５
ＵＶ−２ ０．１１０
ＯＩＬ−２ ０．３０
ゼラチン １．３２
第１５層（第２保護層）
ＰＭ−１ ０．１５
ＰＭ−２ ０．０４
ＷＡＸ−１ ０．０２
Ｄ−１ ０．００１
ゼラチン ０．５５
上記沃臭化銀の特徴を下記に表示する（下記乳剤の平均粒径とは同体積の立方体の一辺長）。
【０２０９】

なお、本発明の代表的なハロゲン化銀粒子の形成例として、沃臭化銀ｄ，ｆの製造例を以下に示す。また、沃臭化銀ａ、ｂ、ｃ、ｅ、ｇ、ｈ、ｉについては沃臭化銀ｄ，ｆの製造例に準ずる。まず種晶乳剤−１の調製作製した。
【０２１０】
種晶乳剤−１の調製
以下のようにして種晶乳剤を調製した。
【０２１１】
特公昭５８−５８２８８号、同５８−５８２８９号に示される混合攪拌機を用いて、３５℃に調整した下記溶液Ａ−１１に硝酸銀水溶液（１．１６１モル）と、臭化カリウムと沃化カリウムの混合水溶液（沃化カリウム２モル％）を、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０ｍＶに保ちながら同時混合法により２分を要して添加し、核形成を行った。続いて、６０分の時間を要して液温を６０℃に上昇させ、炭酸ナトリウム水溶液でｐＨを５．０に調整した後、硝酸銀水溶液（５．９０２モル）と、臭化カリウムと沃化カリウムの混合水溶液（沃化カリウム２モル％）を、銀電位を９ｍＶに保ちながら同時混合法により、４２分を要して添加した。添加終了後４０℃に降温しながら、通常のフロキュレーション法を用いて直ちに脱塩、水洗を行った。
【０２１２】
得られた種晶乳剤は、平均球換算直径が０．２４μｍ、平均アスペクト比が４．８、ハロゲン化銀粒子の全投影面積の９０％以上が最大辺長比率（各粒子の最大辺長と最小辺長との比）が１．０〜２．０の六角状の平板状粒子からなる乳剤であった。この乳剤を種晶乳剤−１と称する。
【０２１３】

沃化銀微粒子乳剤ＳＭＣ−１の調製
０．０６モルの沃化カリウムを含む６．０重量％のゼラチン水溶液５リトッルを激しく攪拌しながら、７．０６モルの硝酸銀水溶液と７．０６モルの沃化カリウム水溶液、各々２リトッルを１０分を要して添加した。この間ｐＨは硝酸を用いて２．０に、温度は４０℃に制御した。粒子調製後に、炭酸ナトリウム水溶液を用いてｐＨを５．０に調整した。得られた沃化銀微粒子の平均粒径は０．０５μｍであった。この乳剤をＳＭＣ−１とする。
【０２１４】
沃臭化銀ｄの調製
０．１７８モル相当の種晶乳剤−１とＨＯ（ＣＨ₂ＣＨ₂Ｏ）_m（ＣＨ（ＣＨ₃）ＣＨ₂Ｏ）_19.8（ＣＨ₂ＣＨ₂Ｏ）_nＨ（ｍ＋ｎ＝９．７７）の１０％エタノール溶液０．５ｍｌを含む、４．５重量％の不活性ゼラチン水溶液７００ｍｌを７５℃に保ち、ｐＡｇを８．４、ｐＨを５．０に調整した後、激しく攪拌しながら同時混合法により以下の手順で粒子形成を行った。
【０２１５】
１） ３．０９３モルの硝酸銀水溶液と０．２８７モルのＳＭＣ−１、及び臭化カリウム水溶液を、ｐＡｇを８．４、ｐＨを５．０に保ちながら添加した。
【０２１６】
２） 続いて溶液を６０℃に降温し、ｐＡｇを９．８に調製した。その後、０．０７１モルのＳＭＣ−１を添加し、２分間熟成を行った（転位線の導入）。
【０２１７】
３） ０．９５９モルの硝酸銀水溶液と０．０３モルのＳＭＣ−１、及び臭化カリウム水溶液を、ｐＡｇを９．８、ｐＨを５．０に保ちながら添加した。
【０２１８】
尚、粒子形成を通して各溶液は、新核の生成や粒子間のオストワルド熟成が進まないように最適な速度で添加した。上記添加終了後に４０℃で通常のフロキュレーション法を用いて水洗処理を施した後、ゼラチンを加えて再分散し、ｐＡｇを８．１、ｐＨを５．８に調整した。
【０２１９】
得られた乳剤は、粒径（同体積の立方体１辺長）０．７４μｍ、平均アスペクト比５．０、粒子内部からヨウ化銀含有率２／８．５／Ｘ／３モル％（Ｘは転位線導入位置）のハロゲン組成を有する平板状粒子からなる乳剤であった。この乳剤を電子顕微鏡で観察したところ乳剤中の粒子の全投影面積の６０％以上の粒子にフリンジ部と粒子内部双方に５本以上の転位線が観察された。表面沃化銀含有率は、６．７モル％であった。
【０２２０】
沃臭化銀ｆの調製
沃臭化銀ｄの調製において、１）の工程でｐＡｇを８．８かつ、添加する硝酸銀量を２．０７７モルＳＭＣ−１の量を０．２１８モルとし、３）の工程で添加する硝酸銀量を０．９１モル、ＳＭＣ−１の量を０．０７９モルとした以外は沃臭化銀ｄと全く同様にして沃臭化銀ｆを調製した。
【０２２１】
得られた乳剤は、粒径（同体積の立方体１辺長）０．６５μｍ、平均アスペクト比６．５、粒子内部からヨウ化銀含有率２／９．５／Ｘ／８．０モル％（Ｘは転位線導入位置）のハロゲン組成を有する平板状粒子からなる乳剤であった。この乳剤を電子顕微鏡で観察したところ乳剤中の粒子の全投影面積の６０％以上の粒子にフリンジ部と粒子内部双方に５本以上の転位線が観察された。表面沃化銀含有率は、１１．９モル％であった。
【０２２２】
上記各乳剤に前述の増感色素を添加、熟成した後、トリフォスフィンセレナイド、チオ硫酸ナトリウム、塩化金酸、チオシアン酸カリウムを添加し、常法に従い、かぶり、感度関係が最適になるように化学増感を施した。
【０２２３】
また、沃臭化銀ａ，ｂ，ｃ，ｅ，ｇ，ｈ，ｉについては、常法に従い、分光増感、化学増感を施した。
【０２２４】
尚、上記の組成物の他に、塗布助剤ＳＵ−１、ＳＵ−２、ＳＵ−３、分散助剤ＳＵ−４、粘度調整剤Ｖ−１、安定剤ＳＴ−１、ＳＴ−２、カブリ防止剤ＡＦ−１、重量平均分子量：１０，０００及び重量平均分子量：１，１００，０００の２種のポリビニルピロリドン（ＡＦ−２）、抑制剤ＡＦ−３、ＡＦ−４、ＡＦ−５、硬膜剤Ｈ−１、Ｈ−２及び防腐剤Ａｓｅ−１を添加した。
【０２２５】
上記試料に用いた化合物の構造を以下に示す。
【０２２６】
【化５】

【０２２７】
【化６】

【０２２８】
【化７】

【０２２９】
【化８】

【０２３０】
【化９】

【０２３１】
【化１０】

【０２３２】
【化１１】

【０２３３】
【化１２】

【０２３４】
【化１３】

【０２３５】
以上で感光材料の試料４０７を作成した。同様にして、Ｅｍ−１を用いて多層カラー写真感光材料４０１を、Ｅｍ−１１を用いて４１１を、Ｅｍ−１３を用いて４１３を作成し、実施例１と同様な評価を行ったところ、表１，２及び表３の単一乳剤層試料と同様な結果が得られた。結果を表４に示す。
【０２３６】
【表４】

【０２３７】
【発明の効果】
本発明により、高感度、かつ圧力耐性、現像処理適性に優れたハロゲン化銀写真乳剤を提供することができた。
【図面の簡単な説明】
【図１】本発明に係る沃化銀輪郭をもつハロゲン化銀粒子の電子顕微鏡による写真である。
【図２】比較のハロゲン化銀乳剤Ｅｍ−３の粒子内の沃化銀含有率の緩慢連続変化状況を表すグラフである。
【図３】本発明のハロゲン化銀乳剤Ｅｍ−５の粒子内の沃化銀含有率の緩慢連続変化状況を表すグラフである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a photographic silver halide emulsion having improved sensitivity, pressure resistance and suitability for development processing.
[0002]
[Prior art]
In recent years, there has been an increasing demand for higher sensitivity and higher image quality of silver halide photographic materials. In addition, recently, there has been an increasing demand for performance improvement that can withstand external factors such as pressure, fluctuations in development processing, and storage under high temperature / high humidity conditions.
[0003]
In response to such demands, attempts have been made to improve the performance of silver halide emulsions by introducing dislocation lines into the silver halide emulsion grains. Japanese Patent Application Laid-Open Nos. 63-220238 and 1-102547 disclose techniques for improving photographic characteristics using dislocation lines.
[0004]
However, in order to respond to the recent high performance requirements of silver halide photographic light-sensitive materials, it is necessary to further improve dislocation line introduction technology. Following the above technical disclosure, technical disclosures regarding many dislocation lines have been made. That is clear. An example is given below.
[0005]
Japanese Patent Laid-Open No. 3-175440 discloses a technique for improving sensitivity and reciprocity characteristics by concentrating dislocation lines at the tops of tabular grains. Japanese Patent Application Laid-Open No. 6-27564 discloses a technique for improving sensitivity and pressure resistance by limiting dislocation lines to the fringe portion of tabular grains.
[0006]
As in these examples, as a result of the conventional technique to be noted, improvement of various performances can be given by limiting the position of dislocation lines to a certain place in the particle. However, by limiting the position of dislocation lines, these technologies also limit the position of degradation factors that occur with dislocation lines, and suppress the effects of canceling the performance improvement effect of dislocation lines. The present inventors considered that it might be.
[0007]
The point which the present inventors paid attention to is the formation of a high iodine layer accompanying the introduction of iodine ions. As described in the prior art disclosure such as JP-A-6-27564, the introduction of dislocation lines is to introduce a gap or misfit of the crystal lattice by introducing iodine ions during grain growth. .
[0008]
However, the technique relating to the silver iodide content continuously changing layer described in JP-A-5-53232, JP-A-9-138473, and JP-A-9-211759 reduces the gap / misfit of the crystal lattice. As a result, improvements in photographic performance such as sensitivity and pressure resistance have been achieved. In other words, due to the introduction of dislocations in the conventional dislocation line technology, the existence of a layer in which the gap / misfit of the crystal lattice, which is inevitably generated, that is, the silver iodide content changes rapidly, is the conventional silver iodide content continuously changing layer. Technology has the potential to negate the effect.
[0009]
However, it is not clear from the conventional research whether a crystal lattice gap / misfit of the degree as in the prior art is essentially indispensable for introducing dislocation lines. It is conceivable that an excessive high silver iodide content layer is formed more than necessary.
[0010]
The presence of a high silver iodide content layer is recognized by current silver halide emulsion researchers. Sensitivity loss due to the high density of lattice defects, pressure resistance degradation, and processing suitability by releasing iodine ions during development. It is possible to easily consider the relationship with deterioration of photographic performance such as deterioration of image quality.
[0011]
In the conventional technical configuration, the layer having a high silver iodide content is formed at the same time as the formation of the dislocation lines, and the effect of improving the photographic performance of the dislocation lines and the high silver iodide content layer. The photographic performance was deteriorated at the same time, and it was thought that the effect of dislocation lines was not sufficiently drawn out.
[0012]
[Problems to be solved by the invention]
An object of the present invention is to provide a silver halide photographic emulsion having high sensitivity, pressure resistance, and development processing suitability.
[0013]
[Means for Solving the Problems]
The above object of the present invention has been achieved by the following constitution.
[0014]
(1) 30% or more of the projected area of all silver halide grains has an aspect ratio of 5 or more, has 30 or more dislocation lines per grain in the fringe part, and extends from the grain center to the grain edge. A silver halide photographic emulsion comprising tabular silver halide grains whose silver iodide content slowly changes continuously.
[0015]
(2) More than 50% of the projected area of all silver halide grains are tabular silver halide grains having an aspect ratio of 5 or more, and one grain of 50% or more of the projected area of all silver halide grains is one grain in the fringe portion. The silver iodide content of tabular silver halide grains having 30 or more dislocation lines per grain and 50% or more of the projected area of all silver halide grains from the grain center toward the grain edge Tabular silver halide grains with slow and continuous changeContainsSilver halide characterized in thatPhotographic emulsion.
[0016]
(3) 50% or more of the projected area of all silver halide grains are tabular silver halide grains having an aspect ratio of 5 or more, and one grain of 50% or more of the projected area of all silver halide grains is in one fringe portion. Tabular silver halide grains having tabular silver halide grains having 30 or more dislocation lines per area and having tabular grains having a silver iodide outline of 20% or less of the projected area of all silver halide grainsContainsIt is characterized bySaid 2Silver halidePhotographic emulsion.
[0017]
(4) Any one of 1 to 3 above, wherein the variation coefficient of the grain size distribution of all silver halide grains is 25% or less and the variation coefficient of the grain thickness distribution is 35% or less. Silver halide described in itemPhotographic emulsion.
[0018]
(5) The silver halide as described in any one of (1) to (4) above, wherein 30 or more dislocation lines per grain are limited to the fringe portion only.Photographic emulsion.
[0019]
(6) The silver halide as described in any one of 1 to 5 above, wherein at least a part of the tabular silver halide grain has a reduction sensitization center inside the grain.Photographic emulsion.
[0020]
(7) The halogenated composition as described in any one of (1) to (6) above, wherein at least a part of the tabular silver halide grains contains at least one polyvalent metal compound in the fringe portion of the grains. SilverPhotographic emulsion.
[0021]
(8) A silver halide photographic emulsion comprising the silver halide grains described in any one of 2 to 7 above.
[0022]
The effects of the present invention are mainly due to the effect of reducing the layer having a high silver iodide content that occurs at the time of dislocation line introduction without deteriorating the introduction efficiency of dislocation lines, and the monodispersity of grains, shallow electrons The present inventors consider that this is a synergistic effect with the trap center and reduction sensitization.
[0023]
That is, the point of the present invention is not to limit the location of the photographic performance deterioration factor that occurs simultaneously with the dislocation line as in the prior art, but to reduce the photographic performance deterioration factor itself.
[0024]
The main point of the present invention is that the dislocation lines are introduced at a high density, and the rapid change in the silver iodide content that is formed at the time of dislocation line introduction is suppressed, so that the silver iodide content over the entire grain is reduced. It can be said that it has achieved a configuration that is not found in the prior art, that is, slow continuous change and high density dislocation line formation.
[0025]
The technique of providing a layer in which the silver iodide content in a grain changes continuously as disclosed in JP-A-9-211759 cannot suppress a rapid change in the silver iodide content accompanying the introduction of dislocation lines. This is essentially different from the present invention.
[0026]
The present invention is described in detail below. The silver halide emulsion of the present invention contains tabular silver halide grains (hereinafter simply referred to as tabular grains). Tabular grains are classified crystallographically as twins.
[0027]
A twin crystal is a silver halide crystal having one or more twin planes in one grain, but the classification of the twin crystals is classified by Klein and Moiser in the form of a photographic photographer Correspondents (Photographe Korrespondenz). The details are described in Vol. 99, p100, Vol. 100, p57.
[0028]
The tabular grains in the present invention have two or more twin planes parallel to the main plane. The twin plane can be observed with a transmission electron microscope. The specific method is as follows. First, a silver halide photographic emulsion is coated on a support so that the contained tabular grains are oriented substantially parallel to each other on a support to prepare a sample. This is cut using a diamond cutter to obtain a thin slice having a thickness of about 0.1 μm. The existence of twin planes can be confirmed by observing this section with a transmission electron microscope.
[0029]
The distance between the two twin planes in the tabular grains of the present invention is an arbitrary 1000 tabular grains showing a cross section cut almost perpendicular to the main plane in the observation of the section using the transmission electron microscope. The distance between the two twin planes having the shortest distance among the even number of twin planes parallel to the main plane is obtained for each particle and obtained by averaging.
[0030]
In the present invention, the average distance between twin planes is preferably 0.01 μm to 0.05 μm, more preferably 0.013 μm to 0.025 μm.
[0031]
In the present invention, the distance between twin planes is a factor that affects the supersaturation state during nucleation, such as gelatin concentration, gelatin species, temperature, iodine ion concentration, pBr, pH, ion supply speed, stirring rotation speed, and the like. It can be controlled by appropriately selecting the combination of factors. In general, the distance between twin planes can be narrowed as nucleation is performed in a highly supersaturated state.
[0032]
Details regarding the supersaturation factor can be referred to, for example, descriptions in JP-A No. 63-92924 or JP-A No. 1-213637.
[0033]
The thickness of the silver halide grains of the present invention is determined by performing metal deposition from an oblique direction of the grains together with the reference latex, taking an electron micrograph, measuring the shadow length on the electron micrograph, It is obtained by referring to the length. In the present invention, the average thickness d of the particles is the thickness d_iFrequency of particles having n_iAnd d_i ^ThreeProduct n_iXd_i ^ThreeThickness d when the maximum is_i(3 significant digits, rounding off the least significant digits). However, the number of measured particles is indiscriminately 600 or more. The average grain thickness d of the silver halide emulsion of the present invention is preferably 0.05 μm to 1.5 μm, more preferably 0.07 μm to 0.50 μm.
[0034]
The grain size of the silver halide grains in the present invention is indicated by the circle equivalent diameter of the projected area of the silver halide grains (the diameter of a circle having the same projected area as the silver halide grains).
[0035]
In the emulsion of the present invention, 50% or more of the total projected area of silver halide grains must be tabular grains having an aspect ratio (grain size / grain thickness) of 5 or more, and preferably 60% of the total projected area. % Or more has an aspect ratio of 6 or more and 80 or less.
[0036]
The particle size of each particle can be obtained by actually measuring the projected area of each particle on an electron micrograph.
[0037]
In the present invention, the average particle size r is equal to the particle size r._iFrequency of particles having n_iAnd r_i ^ThreeProduct n_iXr_i ^ThreeParticle size r when_iIt is defined as However, the number of measured particles is indiscriminately 600 or more. In the present invention, the average particle size is preferably 0.1 to 5.0 μm, more preferably 0.2 to 2.5 μm.
[0038]
The silver halide grains of the present invention are preferably monodispersed silver halide emulsions.
[0039]
The emulsion of the present invention
(Particle size r_iStandard deviation / average particle size r) × 100 = coefficient of variation of particle size distribution [%]
When the width of the distribution is defined by the formula (1), it is preferably 25% or less, more preferably 20% or less, and still more preferably 16% or less. In the present invention, the monodispersed silver halide emulsion means that the variation coefficient of the particle size distribution is 25% or less.
[0040]
Similarly, the emulsion of the present invention

Is defined as 35% or less, more preferably 25% or less, and still more preferably 20% or less.
[0041]
The tabular grain in the present invention is preferably a grain composed of a core serving as a nucleus and a shell covering the core, and the shell is formed of one or more layers.
[0042]
When the tabular grains of the present invention are composed of the above core / shell type grains, the halogen composition of the core and the shell can be arbitrarily selected as long as it satisfies the requirements of the present invention. The silver content is preferably 5 mol% or less, and more preferably 3 mol% or less. The difference in the average silver iodide content between the shell and the core is preferably 2 mol% or less.
[0043]
The proportion of the core is preferably 1 to 60%, and more preferably 4 to 40%, of the total silver amount.
[0044]
In the present invention, the average silver iodide content of the whole tabular grain is preferably 10 mol% or less, more preferably 7 mol% or less, and still more preferably 4 mol% or less.
[0045]
The tabular grains of the present invention are emulsions mainly containing silver iodobromide as described above, but silver halides having other compositions such as silver chloride can be contained within a range not impairing the effects of the present invention.
[0046]
As a means for forming tabular grains of the present invention, various methods well known in the art can be used. In other words, single jet method, controlled double jet method, controlled triple jet method, etc. can be used in any combination, but in order to obtain highly monodisperse grains, silver halide grains are generated. It is important to control the pAg in the liquid phase to be adjusted according to the growth rate of the silver halide grains. As the pAg value, a region of 7.0 to 11.5 is used, preferably 7.5 to 11.0, and more preferably 8.0 to 10.5.
[0047]
In determining the addition rate, the techniques described in JP-A-54-48521 and JP-A-58-49938 can be referred to.
[0048]
During the production of the tabular grains of the present invention, a known silver halide solvent such as ammonia or thioether may be present, or a silver halide solvent may not be used.
[0049]
The tabular grains of the present invention may be grains in which a latent image is mainly formed on the surface or grains mainly formed inside the grains.
[0050]
The tabular grains of the present invention are produced in the presence of a dispersion medium, that is, in a solution containing the dispersion medium. Here, the aqueous solution containing a dispersion medium means that a protective colloid is formed in an aqueous solution by gelatin or other substances that can constitute a hydrophilic colloid (such as a substance that can serve as a binder), preferably colloidal protection. An aqueous solution containing gelatin.
[0051]
In the practice of the present invention, when gelatin is used as the protective colloid, the gelatin may be either lime-treated or acid-treated. Details of the gelatin production method are described in Arthur Guice, The Macromolecular Chemistry of Gelatin (Academic Press, 1964).
[0052]
Examples of hydrophilic colloids other than gelatin that can be used as protective colloids include gelatin derivatives, graft polymers of gelatin and other polymers, proteins such as albumin and casein; hydroxyethyl cellulose, carboxymethyl cellulose, cellulose sulfate esters, and the like. Sugar derivatives such as cellulose derivatives, sodium alginate, starch derivatives; polyvinyl alcohol, polyvinyl alcohol partial acetal, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, polyvinylpyrazole, etc. There are a variety of synthetic hydrophilic polymer materials such as copolymers.
[0053]
In the case of gelatin, it is preferable to use a gelatin having a jelly strength of 200 or more in the paggy method.
[0054]
The silver halide emulsion of the present invention may be one obtained by removing unnecessary soluble salts after completion of the growth of silver halide grains, or it may be contained as it is.
[0055]
Further, desalting can be performed at any point of silver halide growth, as in the method described in JP-A-60-138538. The salt can be removed based on the method described in Research Disclosure (hereinafter abbreviated as RD) No. 17643, Item II. More specifically, in order to remove soluble salts from the emulsion after precipitation or after physical ripening, a Nudell water washing method in which gelatin is gelled may be used, and inorganic salts, anionic surfactants, A precipitation method (flocculation) using an anionic polymer (for example, polystyrene sulfonic acid) or a gelatin derivative (for example, acylated gelatin, carbamoylated gelatin, etc.) may be used.
[0056]
In the present invention, the silver iodide content and the average silver iodide content of individual silver halide grains can be determined by using an EPMA method (Electron Probe Micro Analyzer method). In this method, a sample in which emulsion grains are well dispersed so as not to contact each other is prepared, and elemental analysis of a very small portion can be performed by X-ray analysis by electron beam excitation in which an electron beam is irradiated. The EPMA method is classified into TEM (transmission type) and SEM (scanning type) depending on the measurement method, and is classified into WDS (wavelength dispersion type) and EDS (energy dispersion type). By determining the characteristic X-ray intensity of silver and iodine emitted from each grain using the EPMA method, the halogen composition of each grain can be determined. If the silver iodide content is determined by EPMA method for at least 50 grains, the average silver iodide content can be determined from the average of them.
[0057]
The tabular grains in the present invention preferably have a more uniform silver iodide content between grains. When the distribution of silver iodide content between grains was measured by the EPMA method, the standard deviation / average value × 100 (%) when the relative standard deviation, that is, the silver iodide content of each grain was used as a characteristic value, was 30. % Or less, more preferably 20% or less.
[0058]
As one of the constitutions of the present invention, 50% or more of the projected area of all silver halide grains is a tabular grain whose silver iodide content changes slowly and continuously from the grain center to the grain edge. Although there is a need for a certain condition, the EPMA method with a sufficiently narrow measurement beam diameter can also be used for this condition. The conditions will be described in detail below.
[0059]
When viewed from the direction perpendicular to the main plane of the tabular silver halide grain, a line segment perpendicular to the side is drawn from the center of the main plane of the tabular grain, and the length of the line segment is 5 to 5 on this line segment. A point is taken every 15%, and the average silver iodide content of a component perpendicular to the main plane of each point, that is, a cylindrical portion having a height corresponding to the measured spot diameter and grain thickness is measured. At this time, it is necessary to narrow the measurement spot to 40 nm or less. In consideration of damage to the sample, it is necessary to cool the measurement temperature to −100 ° C. or lower. The integration time at each measurement point is 30 seconds or more. The change in silver iodide content between each measurement spot is the value obtained by dividing the difference in the measured silver iodide content (mol%) between the two measurement points by the distance between the measurement points. The case where it increases toward the outside is positive, and the case where it decreases is negative. In the present invention, when the change in silver iodide content between points from the center to the side direction is within the range of -0.03 mol% / nm to +0.03 mol% / nm, the grain center to the grain edge Toward, the silver iodide content is defined as a slow continuous change. The change in silver iodide content is preferably −0.01 mol% / nm to +0.02 mol% / nm, and more preferably 0.00 mol% / nm to +0.01 mol% / nm.
[0060]
The ratio of tabular grains whose silver iodide content changes slowly and continuously is preferably 70% or more, more preferably 90% or more, relative to the projected area of all silver halide grains.
[0061]
The halide composition on the surface of the tabular grain of the present invention is determined by the XPS method (X-ray Photoelectron Spectroscopy method: X-ray photoelectron spectroscopy) as follows.
[0062]
The XPS method has been conventionally used as a method for determining the silver iodide content on the surface of silver halide grains, and is disclosed in JP-A-2-24188. However, when the measurement was carried out at room temperature, the sample accompanying the X-ray irradiation was destroyed, so the exact silver iodide content of the outermost layer could not be determined. The inventors have succeeded in accurately obtaining the silver iodide content of the surface layer by cooling the sample to a temperature at which destruction does not occur, specifically to about −110 ° C. or less. As a result, in particular for particles such as core / shell particles having different surface and internal compositions, and particles having a high and low iodine layer localized on the outermost surface, the measured value at room temperature is X-ray. It was revealed that the true composition differs greatly due to the decomposition of silver halide and the diffusion of halide (especially iodine) upon irradiation.
[0063]
The XPS method used in the present invention is specifically as follows. A 0.05% by weight aqueous solution of proteolytic enzyme (pronase) was added to the emulsion, and the mixture was stirred at 45 ° C. for 30 minutes to decompose gelatin. This is centrifuged to settle the emulsion grains, and the supernatant is removed. Next, distilled water is added to disperse the emulsion grains in the distilled water, and the mixture is centrifuged to remove the supernatant. The emulsion grains are dispersed in water and thinly coated on a mirror-polished silicon wafer to obtain a measurement sample. Using the sample prepared in this manner, surface iodine measurement was performed by XPS. In order to prevent destruction of the sample due to X-ray irradiation, the sample was cooled to −110 to −120 ° C. in the XPS measurement chamber. As a probe X-ray, MgKα is irradiated with an X-ray source voltage of 15 kV and an X-ray source current of 40 mA._5/2, Br3d, I3d_3/2Measured for electrons. The integrated intensity of the measured peak was corrected with a sensitivity factor, and the halide composition on the surface was determined from these intensity ratios. The silver iodide content on the surface of the silver halide grains in the present invention is the silver iodide content of the outermost layer of the silver halide grains that can be determined by the method described above. The outermost layer of silver halide grains is the outermost layer of grains including the outermost surface of silver halide grains and means a layer having a depth of 50 mm from the outermost surface of the grains.
[0064]
The tabular grains in the present invention preferably have a silver iodide content on the grain surface higher than the average silver iodide content of the grains. That is, it is preferable to satisfy the relationship of silver iodide content / average silver iodide content = 1.1 to 8 on the grain surface, and more preferably silver iodide content / average silver iodide content on the grain surface. = 1.3-5 is satisfied.
[0065]
The silver halide emulsion of the present invention is characterized in that tabular grains having 30 or more dislocation lines per grain in the fringe portion occupy 50% or more of the total projected area. The ratio of grains having 30 or more dislocation lines per grain in the fringe portion to the total projected area is preferably 60%, more preferably 70%.
[0066]
The dislocations of silver halide grains are described in, for example, J. Org. F. Hamilton, Photo. Sci. Eng. , Vol 11, 57 (1967), T. 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, vol 35, 213 (1972). In other words, the silver halide grains taken out carefully so as not to apply a pressure that causes dislocations to the grains from the emulsion are placed on a mesh for observation with an electron microscope 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 an 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). it can.
[0067]
From the photograph of particles obtained by such a method, the position and number of dislocations for each particle when viewed from a direction perpendicular to the main plane can be obtained.
[0068]
In this invention, having a dislocation line in a fringe part means that a dislocation line exists in the vicinity of the outer peripheral part of a tabular grain, the vicinity of a ridgeline, or the vertex. Specifically, the fringe part is a line segment connecting the centroid and the vertex when the tabular grain is observed perpendicularly to the main plane and the center of the main plane of the tabular grain, that is, the main plane is regarded as a two-dimensional figure. When the length is L, it refers to the area outside the figure connecting the points whose distance from the center is 0.50 L for each vertex.
[0069]
In the silver halide emulsion of the present invention, it is preferable that 50% or more of the projected area of all silver halide grains are tabular grains in which dislocation lines are limited only to the fringe portion. More preferably, the proportion of the tabular grains whose dislocation lines are limited to the fringe portion is 60% or more of the projected area of all silver halide grains, and more preferably 70% or more. Further, the region where the dislocation line is limited is more preferably a region on the line segment connecting the center and the vertex of the main plane and outside the figure connecting the points having a distance of 0.70 L from the center. More preferably, the region is outside the figure connecting the points of 0.80L.
[0070]
The direction of the dislocation line is approximately the direction from the center toward the outer surface (side surface), but is often meandering.
[0071]
As a method for introducing dislocation lines into silver halide grains, for example, a method of adding an aqueous solution containing iodine ions such as potassium iodide and a water-soluble silver salt solution by a double jet, or a method of adding only a solution containing iodine ions A method of adding a fine grain emulsion containing silver iodide, a method of using an iodine ion releasing agent as described in JP-A-6-11781, and the like are known.
[0072]
An effective method for obtaining the emulsion of the present invention is a method using an iodine ion releasing agent. What is iodine ion releaser?
R¹-I
A compound that releases iodine ions by a reaction with a base or a nucleophile represented by the general formula: R¹Represents a monovalent organic group. R¹Is an alkyl group, alkenyl group, alkynyl group, aryl group, aralkyl group, heterocyclic group, acyl group, carbamoyl group, alkyloxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group, sulfamoyl group Is preferred. R¹Is preferably an organic group having 30 or less carbon atoms, more preferably 20 or less, and even more preferably 10 or less.
[0073]
Also R¹Preferably has a substituent, and the substituent may be further substituted with another substituent.
[0074]
Preferred examples of the substituent include a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, a heterocyclic group, an acyl group, an acyloxy group, a carbamoyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, and an alkylsulfonyl group. , Arylsulfonyl group, sulfamoyl group, alkoxy group, aryloxy group, amino group, acylamino group, ureido group, urethane group, sulfonylamino group, sulfinyl group, phosphoric acid amide group, alkylthio group, arylthio group, cyano group, sulfo group , Carboxyl group, hydroxy group, and nitro group.
[0075]
Iodine ion release agent R¹As -I, iodoalkanes, iodoalcohols, iodocarboxylic acids, iodoamides and derivatives thereof are preferred, iodoamides, iodoalcohols and derivatives thereof are more preferred, iodoamides substituted with a heterocyclic group are more preferred, A preferred example is (iodoacetamido) benzene sulfonate.
[0076]
Specific examples of iodine ion releasing agents that can be preferably used are shown below.
[0077]
[Chemical 1]

[0078]
When an iodine ion releasing agent and a nucleophilic reagent are reacted to release iodine ion, hydroxide ion, sulfite ion, thiosulfate ion, sulfinate, carboxylate, ammonia, amines, Alcohols, ureas, thioureas, phenols, hydrazines, sulfides, hydroxamic acids, etc. can be used, hydroxide ions, sulfite ions, thiosulfate ions, sulfinates, carboxylates, ammonia, Amines are preferable, and hydroxide ions and sulfite ions are more preferable.
[0079]
The present inventors have found that the emulsion of the present invention can be produced by adjusting the conditions for releasing iodine ions using an iodine ion releasing agent. In the following, preferable iodine ion release reaction conditions are described for producing the emulsion of the present invention.
[0080]
In the iodine ion releasing reaction when producing the emulsion of the present invention, it is preferable that 50% of the added iodine ion releasing agent releases iodine ions within a time period of 30 seconds to 180 seconds. The release rate of iodine ions can be determined by monitoring the pAg during the reaction. Conversion from pAg to iodine ion release can be made by preparing a calibration curve in advance using a water-soluble iodide such as KI.
[0081]
The release rate of iodine ions can be adjusted by the addition amount of the iodine ion releasing agent and the nucleophilic agent, the molar ratio of the iodine ion releasing agent and the nucleophilic agent, the concentration of the nucleophilic agent, the pH, and the temperature.
[0082]
In the iodine ion releasing reaction in producing the emulsion of the present invention, the reaction temperature is preferably 45 ° C. or less, more preferably 40 ° C. or less, and further preferably 35 ° C. or less. pBr is preferably 1.50 or less, more preferably 1.30 or less, and even more preferably 1.10 or less.
[0083]
The amount of iodine ion releasing agent to be added is preferably 3.5 mol% or less, more preferably 1.5 mol% or less, and more preferably 1.0 mol% with respect to the total silver mol amount after completion of grain growth. More preferably, it is as follows.
[0084]
Further, when a nucleophilic agent is used during the iodine ion releasing reaction, the reaction is preferably carried out at a pH of 9.0 or more and 12.0 or less if the nucleophilic agent is only hydroxide ions. More preferably, it is 0 or more and 11.0 or less. When the nucleophilic agent is other than hydroxide ions, the amount of the nucleophilic agent is preferably 0.25 to 2.0 times the amount of the iodine ion releasing agent in terms of molar ratio, 0.50 It is more preferable that the number is 1.5 times or more and more preferably 0.80 times or more and 1.2 times or less. When the nucleophilic agent is other than hydroxide ions, the pH during the iodine ion releasing reaction is preferably 8.5 or more and 10.5 or less, more preferably 9.0 or more and 10.0 or less. preferable. The nucleophilic agent is preferably added after the addition of the iodine ion releasing agent is started, and more preferably added after the addition of the iodine ion releasing agent is completed.
[0085]
In the present invention, the dislocation line introduction position is a portion where iodide ions are introduced into the grains by the above method.
[0086]
One silver halide emulsion of the constitution of the present invention has an aspect ratio of 5 or more, 30 or more dislocation lines in the fringe part, and silver iodide from the grain center to the grain edge. It contains tabular silver halide grains whose content rate changes slowly and continuously. The tabular grains are 30% or more of the projected area of all silver halide grains, more preferably 40% or more, and most preferably 50% or more.
[0087]
In one of the constitutions of the present invention, the tabular grains having a silver iodide outline are required to be 20% or less of the projected area of all silver halide grains. Tabular grains having a silver iodide contour are preferably less than 15% of the projected area of all silver halide grains, more preferably less than 10%, even more preferably less than 5%, most preferably 0%. is there. However, observation is performed on 600 or more particles.
[0088]
The silver iodide contour is a term defined by the present inventors and can be observed by the same method as a dislocation line. In the present invention, in TEM observation, a portion formed by a contour line having a width of several nm to several tens of nm, which is almost similar to the outer peripheral shape of the grain and is found near the dislocation line introduction position, is defined as a silver iodide contour. . When the silver iodide content of this part is examined by the EPMA method, a value of 8 mol% to 15 mol% is shown. It is a layer having a high silver iodide content generated simultaneously with the introduction of dislocation lines. It is considered that due to the difference in silver iodide content, the electron beam transmission / scattering rate is different from other parts and is observed by TEM. FIG. 1 shows an example of silver iodide contour.
[0089]
As a preferred embodiment of the present invention, at least one polyvalent metal compound is contained in the fringe portion of the tabular grain. Inclusion of a polyvalent metal compound in silver halide grains is called metal dope or simply dope.
[0090]
Metal doping is a well-known technique in the art. For example, it has been reported by Leubner that when an iridium complex is doped into silver halide, it becomes an electron capture center (The Journal of Photographic Science Vol. 31, 93 (1983)). A metal compound used for metal doping is called a metal dopant or simply a dopant. In the present invention, one or more metal dopants can be present at any position in the grain, but as described above, the preferred form contains at least one or more polyvalent metal compound in the fringe portion of the tabular grain. That is.
[0091]
In the present invention, Mg, Al, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb, Mo, Tc, Ru are used as metal dopants. Metal compounds such as Rh, Pd, Cd, Sn, Ba, Ce, Eu, W, Re, Os, Ir, Pt, Hg, Tl, Pd, Bi, and In can be preferably used.
[0092]
The metal compound to be doped is preferably selected from a single salt or a metal complex. When selecting from a metal complex, a 6-coordinate, a 5-coordinate, a 4-coordinate, and a 2-coordinate complex are preferable, and an octahedral 6-coordinate and a planar 4-coordinate complex are more preferable. The complex may be a mononuclear complex or a polynuclear complex. As a ligand constituting the complex, CN^-, CO, NO₂ ^-1,10-phenanthroline, 2,2'-bipyridine, SO_Three ^-, Ethylenediamine, NH_Three, Pyridine, H₂O, NCS^-, NCO^-, NO_Three ^-, SO_Four ^2-, OH^-, CO_Three ^2-, SSO_Three ^2-, N_Three ^-, S₂ ^-, F^-, Cl^-, Br^-, I^-Etc. can be used. NCS^-Can be coordinated by either N atom or S atom.
[0093]
As a specific example of a preferred metal compound to be doped of the present invention,
K_FourFe (CN)₆, K_ThreeFe (CN)₆, Pb (NO_Three)₂, K₂IrCl₆, K_ThreeIrCl₆, K₂IrBr₆, InCl_ThreeCan be given.
[0094]
The concentration distribution of the metal dopant in the silver halide grains can be determined by dissolving the grains little by little from the surface to the inside and measuring the dopant content in each part. Specific examples include the methods described below.
[0095]
Prior to quantification of the metal, the silver halide emulsion is pretreated as follows. First, 50 ml of 0.2% actinase aqueous solution is added to about 30 ml of the emulsion, and the mixture is stirred at 40 ° C. for 30 minutes for gelatin degradation. This operation is repeated 5 times. After centrifugation, washing is repeated 5 times with 50 ml of methanol, 2 times with 50 ml of 1N nitric acid, and 5 times with ultrapure water. After centrifugation, only the silver halide is separated. The surface portion of the obtained silver halide grains is dissolved by an aqueous ammonia solution or ammonia whose pH is adjusted (the ammonia concentration and pH are changed according to the type and amount of dissolution of silver halide). As a method of dissolving the extreme surface of silver bromide grains in silver halide, about 3% of the grain surface can be dissolved by using 20 ml of about 10% aqueous ammonia solution per 2 g of silver halide. At this time, the amount of silver halide dissolved is determined by centrifuging the aqueous ammonia solution and silver halide after dissolution of the silver halide, and determining the amount of silver present in the resulting supernatant by a high frequency induction plasma mass spectrometer. (ICP-MS) It can be quantified by a high frequency induction plasma emission spectrometer (ICP-AES) or by atomic absorption. The amount of metal per mole of silver halide present at about 3% of the grain surface can be obtained from the difference between the amount of metal contained in the silver halide after dissolution and the total amount of silver halide not dissolved. it can. Examples of the metal quantification method include ICP-MS method, ICP-AES method, or atomic absorption method, which is dissolved in ammonium thiosulfate aqueous solution, sodium thiosulfate aqueous solution, or potassium cyanide aqueous solution and is matrix-matched. Of these, when potassium cyanide is used as a solvent and ICP-MS (manufactured by FSON Elemental Analysis) is used as an analyzer, an internal standard element Cs solution is prepared so that about 40 mg of silver halide is dissolved in 5 ml of 0.2N potassium cyanide to 10 ppb. The sample was made up to a volume of 100 ml with ultrapure water and used as a measurement sample. Then, the metal in the measurement sample is quantified by ICP-MS using a calibration curve in which the matrix is combined using metal-free silver halide. At this time, the exact amount of silver in the measurement sample can be quantified by ICP-AES or atomic absorption of the measurement sample diluted 100 times with ultrapure water. After such dissolution of the grain surface, the silver halide grains are washed with ultrapure water, and the dissolution of the grain surface is repeated in the same manner as described above, so that the metal in the inner direction of the silver halide grains is obtained. The quantity can be quantified.
[0096]
By combining the ultrathin section preparation method described above and the metal determination method, the metal doped in the outer peripheral region of the tabular grain of the present invention can be determined.
[0097]
The preferred content of the metal dopant in the tabular grains of the present invention is 1 × 10 5 per mole of silver halide.^-9Mol ~ 1 × 10^-FourMol, more preferably 1 × 10^-8Mol ~ 1 × 10^-FiveIs a mole.
[0098]
In the tabular grain of the present invention, the ratio of the amount of metal dopant contained in the outer peripheral region / the amount of metal dopant contained in the central region of the main plane is 5 times or more, preferably 10 times or more, more preferably 20 times or more. is there.
[0099]
By adding the metal dopant to the base grain in a state doped in advance in the silver halide fine grain emulsion, the effect is effectively exhibited. At this time, the concentration of the metal dopant with respect to 1 mol of silver halide fine particles is 1 × 10.^-1Mol ~ 1 × 10^-7Moles are preferred, 1 × 10^-3Mol ~ 1 × 10^-FiveMole is more preferred.
[0100]
As a method of doping silver halide fine particles with a metal dopant in advance, it is preferable to form fine particles in a state where the metal dopant is dissolved in a halide solution.
[0101]
The halogen composition of the silver halide fine grains may be any of silver bromide, silver iodide, silver chloride, silver iodobromide, silver chlorobromide, and silver chloroiodobromide, but the same halogen composition as the base grain. Is preferred.
[0102]
The time for depositing silver halide fine particles containing metal dopant on the base grain may be anywhere from the base grain formation to before the start of chemical sensitization, but from the end of the desalting process to before the start of chemical sensitization. Is particularly preferred. By adding the fine grain emulsion in a state where the salt concentration of the base emulsion is low, the silver halide fine grains are deposited together with the metal dopant on the portion where the base grain has the highest activity. That is, it can be efficiently deposited on the outer peripheral region including the corners and edges of the tabular grains of the present invention. This deposition means that the silver halide fine particles are dissolved in the reaction system in which the silver halide fine particles and the base particles coexist, instead of agglomerating and adsorbing the silver halide fine particles to the base particles as they are. Regeneration as silver halide. That is, when a part of the emulsion obtained by the above method is taken out and observed with an electron microscope, silver halide fine particles are not observed, and epitaxial protrusions are not observed on the surface of the base particle. Say.
[0103]
The silver halide fine particles to be added are 1 × 10 5 per mol of the base grains.^-7It is preferable to add a silver amount of 1 mol to 0.5 mol.^-FiveMol ~ 1 × 10^-1It is more preferable to add a molar amount of silver.
[0104]
Physical ripening conditions for depositing silver halide fine particles can be arbitrarily selected between 30 ° C. and 70 ° C./10 minutes to 60 minutes.
[0105]
A preferred embodiment of the present invention is that at least a part of tabular grains contained in the silver halide emulsion of the present invention has a reduction sensitization center inside the grains.
[0106]
Having a reduction sensitization center inside a grain means having a fine silver nucleus formed by reduction sensitization inside the grain, and is achieved by performing a reduction sensitization treatment before the end of the growth of silver halide grains. The
[0107]
The inside of the grain refers to a portion of the silver halide grain other than the outermost layer of the grain, and is preferably inside of 90%, more preferably inside of 70%, and further inside of 50% in the whole volume of the grain. preferable. The silver nucleus-containing layer is preferably present inside the dislocation line introducing portion described later.
[0108]
Reduction sensitization is performed by adding a reducing agent to a silver halide emulsion or a mixed solution for grain growth. Alternatively, it is performed by ripening or growing a silver halide emulsion or a mixed solution for grain growth under a low pAg of pAg7 or less, or under a high pH condition of pH7 or more. Moreover, it can also carry out combining these methods. A preferred method is a method of adding a reducing agent.
[0109]
Preferred examples of the reducing agent include thiourea dioxide (formamidine sulfinic acid), ascorbic acid and its derivatives, and stannous salts. Other suitable reducing agents include borane compounds, hydrazine derivatives, silane compounds, amines and polyamines and sulfites. The amount added is 10 per mole of silver halide.^-2-10^-8Moles are preferred, 10^-Four-10^-6Mole is more preferred.
[0110]
In order to perform low pAg ripening, a silver salt can be added, but a water-soluble silver salt is preferred. Silver nitrate is preferred as the water-soluble silver salt. The pAg at the time of aging is suitably 7 or less, preferably 6 or less, more preferably 1 to 3 (where pAg = −log [Ag⁺].
[0111]
High pH ripening is performed, for example, by adding an alkaline compound to a silver halide emulsion or a mixed solution of grain growth. As the alkaline compound, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonia and the like can be used. In the method of adding ammoniacal silver nitrate for silver halide formation, an alkaline compound excluding ammonia is preferably used because the effect of ammonia is reduced.
[0112]
As a method for adding a reduction sensitizer, a silver salt, or an alkaline compound for reduction sensitization, rush addition may be used, or addition over a certain period of time. In this case, it may be added at a constant flow rate, or may be added while changing the flow rate as a function. Further, the necessary amount may be added in several divided portions. Prior to the addition of the soluble silver salt and / or the soluble halide into the reaction vessel, it may be present in the reaction vessel, or may be mixed in the soluble halide solution and added together with the halide. Further, the addition may be performed separately from the soluble silver salt and the soluble halide.
[0113]
The silver halide grains contained in the silver halide emulsion of the present invention preferably have a silver chalcogenide nucleus-containing layer in the grains. The chalcogenide core-containing layer is preferably outside of 50%, more preferably outside of 70% in terms of the volume of the whole grain. Although the silver chalcogenide nucleus-containing layer may or may not be in contact with the grain surface, the chemical sensitization of the chalcogenide formed by chemical sensitization and the silver chalcogenide nucleus-containing layer of the present invention The contained chalcogenide nuclei are clearly distinguished in that their confidence forms a latent image forming center. That is, the silver chalcogenide nuclei contained in the silver chalcogenide nucleus-containing layer of the present invention are required to have a lower electron capturing ability than the chemical sensitization nuclei. Silver chalcogenide nuclei satisfying such conditions are formed by a method described later.
[0114]
The silver chalcogenide nucleus-containing layer is preferably present outside the dislocation line introduction part.
[0115]
The chalcogenide nuclei are formed by the addition of a compound capable of releasing chalcogen ions. Preferred silver chalcogenide nuclei are silver sulfide nuclei, silver selenide nuclei and silver telluride nuclei, more preferably silver sulfide nuclei.
[0116]
As the compound capable of releasing chalcogen ions, a compound capable of releasing sulfide ions, selenide ions and telluride ions is preferably used.
[0117]
As compounds capable of releasing sulfide ions, thiosulfonic acid compounds, disulfide compounds, thiosulfates, sulfide salts, thiocarbamide compounds, thioformamide compounds, and rhodanine compounds can be preferably used.
[0118]
As the compound capable of releasing selenide ions, those known as selenium sensitizers can be preferably used. Specifically, colloidal selenium metal, isoselenocyanates (for example, allyl isoselenocyanate, etc.), selenoureas (for example, N, N-dimethylselenourea, N, N, N-triethylselenourea, N, N, N-trimethyl-N-heptafluoroselenourea, N, N, N-trimethyl-N-heptafluoropropylcarbonylselenourea, N, N, N-trimethyl-N-4-nitrophenylcarbonylselenourea, etc.), selenoketones (Eg, selenoacetamide, N, N-dimethylselenobenzamide, etc.), selenophosphates (eg, tri-p-triselenophosphate, etc.), selenides (eg, diethyl selenide, diethyl diselenide, triethylphosphine) Selenide).
[0119]
Examples of compounds capable of releasing telluride ions include telluroureas (for example, N, N-dimethyltellurourea, tetramethyltellurourea, N-carboxyethyl-N, N-dimethyltellurourea, etc.), phosphine tellurides ( For example, tributylphosphine telluride, tricyclohexylphosphine telluride, triisopropylphosphine telluride, etc.), telluramides (eg, telluroacetamide, N, N-dimethyltellurobenzamide, etc.), telluroketones, telluroesters, isoterrocyanates Etc.
[0120]
A particularly preferable compound capable of releasing chalcogen ions is a thiosulfonic acid compound, and examples thereof include thiosulfonate compounds represented by the following formulas [1] to [3].
[0121]
[1] R-SO₂SM
[2] R-SO₂S-R₁
[3] RSO₂S-Lm-SSO₂-R₂
Where R, R₁And R₂May be the same or different and each represents an aliphatic group, an aromatic group or a heterocyclic group, M represents a cation, L represents a divalent linking group, and m represents 0 or 1.
[0122]
The compounds represented by the formulas [1] to [3] may be a polymer containing a divalent group derived from these structures as a repeating unit, and R, R₁, R₂, L may be bonded to each other to form a ring.
[0123]
The thiosulfonate compound represented by the formulas [1] to [3] will be described in more detail. R, R₁, R₂Is an aliphatic group, a saturated or unsaturated linear, branched or cyclic aliphatic hydrocarbon group, preferably an alkyl group having 1 to 22 carbon atoms (methyl, ethyl, propyl, butyl, pentyl, Hexyl, octyl, 2-ethylhexyl, decyl, dodecyl, hexadecyl, octadecyl, cyclohexyl, isopropyl, t-butyl, etc., alkenyl groups having 2 to 22 carbon atoms (allyl, butenyl, etc.), and alkynyl groups (propargyl, butynyl) Etc.) and these may have a substituent.
[0124]
R, R₁, R₂Is an aromatic group, it contains a monocyclic or condensed aromatic group, preferably has 6 to 20 carbon atoms, and examples thereof include phenyl and naphthyl. These may have a substituent.
[0125]
R, R₁, R₂Is a 3- to 15-membered ring having at least one element selected from nitrogen, oxygen, sulfur, selenium and tellurium and at least one carbon atom, preferably a 3- to 6-membered ring. Yes, examples include pyrrolidine, piperidine, pyridine, tetrahydrofuran, thiophene, oxazole, thiazole, imidazole, benzothiazole, benzoxazole, benzimidazole, selenazole, benzoselenazole, tetrazole, triazole, benzotriazole, oxadiazole, thiadiazole ring .
[0126]
R, R₁, R₂Examples of the substituent include alkyl groups (for example, methyl, ethyl, hexyl), alkoxy groups (for example, methoxy, ethoxy, octyloxy), aryl groups (for example, phenyl, naphthyl, tolyl), hydroxy groups, halogen atoms (for example, , Fluorine, chlorine, bromine, iodine), aryloxy groups (eg, phenoxy), alkylthio groups (eg, methylthio, butylthio), arylthio groups (eg, phenylthio), acyl groups (eg, acetyl, propionyl, butyryl, valeryl), A sulfonyl group (eg, methylsulfonyl, phenylsulfonyl), an acylamino group (eg, acetylamino, benzoylamino), a sulfonylamino group (eg, methanesulfonylamino, benzenesulfonylamino), an acyloxy group (eg, acetoacetate) Shi, benzoxy), a carboxyl group, a cyano group, a sulfo group, an amino group, -SO₂SM group (M represents a monovalent cation), -SO₂R₁Groups.
[0127]
Examples of the divalent linking group represented by L include an atom or an atomic group containing at least one selected from C, N, S and O. Specifically, an alkylene group, an alkenylene group, an alkynylene group, an arylene group, -O-, -S-, -NH-, -CO-, -SO₂-Or the like, or a combination thereof.
[0128]
L is preferably a divalent aliphatic group or a divalent aromatic group. Examples of the divalent aliphatic group include:
[0129]
[Chemical 2]

[0130]
Examples include a xylylene group. Examples of the divalent aromatic group include a phenylene group and a naphthylene group.
[0131]
These substituents may be further substituted with the substituents described so far.
[0132]
M is preferably a metal ion or an organic cation. Examples of the metal ion include lithium ion, sodium ion, and potassium ion. Examples of organic cations include ammonium ions (ammonium, tetramethylammonium, tetrabutylammonium, etc.), phosphonium ions (tetraphenylphosphonium, etc.), and guanidyl groups.
[0133]
When the compound represented by the formulas [1] to [3] is a polymer, examples of the repeating unit include the following. These polymers may be homopolymers or copolymers with other copolymerization monomers.
[0134]
[Chemical Formula 3]

[0135]
Specific examples of the compounds represented by the formulas [1] to [3] are described in, for example, JP-A No. 54-1019, British Patent No. 972, 211, Journal of Organic Chemistry vol. 53, p. 396 (1988).
[0136]
The amount of the compound capable of releasing chalcogen ions for forming a chalcogenide nucleus is 10 per mol of silver halide.^-2-10^-8Moles are preferred, 10^-3-10^-6Is more preferable.
[0137]
As a method for adding a compound capable of releasing chalcogen ions for forming a chalcogenide nucleus, rush addition may be used, or addition may be performed over a certain period of time. In this case, it may be added at a constant flow rate, or may be added while changing the flow rate as a function. Further, the necessary amount may be added in several divided portions. It is necessary to form the chalcogenide nuclei by the end of grain formation. Although the formation of the chalcogenide nuclei may or may not be performed after the grain formation, the silver chalcogenide nuclei formed after the grain formation are incorporated as part of the chemical sensitization nuclei formed in the chemical sensitization process, Substantially does not contribute to the effect of the present invention. Similarly, even when chemical sensitization is performed inside the grains, silver chalcogenide nuclei formed on the same plane as the chemical sensitization do not substantially contribute to the effects of the present invention.
[0138]
In the silver halide emulsion of the present invention, an oxidizing agent for silver can be added during the production process in addition to the oxidizing agent for silver contained in the compound capable of releasing chalcogen ions. The oxidizing agent for silver refers to a compound having an action of acting on metallic silver to convert it into silver ions.
[0139]
The oxidizing agent for silver may be an inorganic substance or an organic substance. Inorganic oxidants include ozone, hydrogen peroxide and its adducts (eg, NaBO).₂・ H₂O₂・ 3H₂O, 2NaCO_Three・ 3H₂O₂, Na_FourP₂O₇・ 2H₂O₂2Na₂SO_Four・ H₂O₂・ H₂O), peroxyacid salts (eg K₂S₂O₈, K₂C₂O₆, K_FourP₂O₈), Peroxy complex compounds (for example, K₂[Ti (O₂) C₂O_Four] 3H₂O, 4K₂SO_Four・ Ti (O₂) OH / SO_Four・ 2H₂O, Na_Three[VO (O₂) (C₂O_Four)₂・ 6H₂O]), permanganate (eg KMnO)_Four), Chromate (eg K₂Cr₂O₇) Oxyacid salts, halogen elements such as iodine and bromine, perhalogenates (eg, potassium periodate), high valent metal salts (eg, potassium hexacyanoferrate) and thiosulfonates Etc. 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, chloramine B). ).
[0140]
As an oxidizing agent for silver, a halogen element is preferably used, and iodine is particularly preferably used. In the present invention, the preferred addition amount of the oxidizing agent to silver is 1 × 10 5 per mol of silver.^-FiveMore than mol 1 × 10^-2mol or less, more preferably 1 × 10 5 per mol of silver as an I atom.^-FourMore than mol 1 × 10^-3or less, and more preferably 5 × 10 5 per mol of silver in terms of I atoms.^-Fivemol × 5 × 10^-Fourmol or less.
[0141]
The silver halide emulsion of the present invention can be used by being mixed with other silver halide emulsions as long as the effects of the present invention are not impaired, in addition to being used alone in the emulsion layer. In the same emulsion layer, when mixed with other silver halide emulsions, it is a preferred mode of use to use a plurality of emulsions of the present invention having different average particle diameters.
[0142]
Examples of preferred usage forms of the emulsion of the present invention in the light-sensitive material are described below.
[0143]
The emulsion of the present invention is used for two or more emulsion layers having the same color sensitivity and different sensitivities. In that case, the average grain size of the emulsion of the present invention contained in each layer is preferably different.
[0144]
The emulsion of the present invention is used in two or more emulsion layers having different color sensitivity and approximate sensitivity. In that case, the average grain size of the emulsion of the present invention contained in each layer is preferably approximate, and it is more preferable to use the same emulsion of the present invention for each layer.
[0145]
-Use the emulsion of the present invention in all emulsion layers.
[0146]
The silver halide emulsion of the present invention can be chemically sensitized by a conventional method. That is, sulfur sensitization, selenium sensitization, noble metal sensitization using gold or other noble metal compounds can be used alone or in combination.
[0147]
The silver halide emulsion of the present invention can be optically sensitized to a desired wavelength range using a dye known as a sensitizing dye in the photographic industry. Sensitizing dyes may be used alone or in combination of two or more. Dye that does not have spectral sensitizing action itself or a compound that does not substantially absorb visible light together with the sensitizing dye, and contains a supersensitizer that enhances the sensitizing action of the sensitizing dye in the emulsion. May be.
[0148]
Antifoggants, stabilizers and the like can be added to the silver halide emulsion of the present invention. It is advantageous to use gelatin as the binder. The emulsion layer and other hydrophilic colloid layers can be hardened and can contain a plasticizer, a water-insoluble or soluble synthetic polymer dispersion (latex).
[0149]
The silver halide photographic emulsion of the present invention can be used for photographic light-sensitive materials, and can be preferably used for color photographic light-sensitive materials such as general-use and movie color films, color papers, color reversal films, and color reversal papers.
[0150]
A coupler is used in the emulsion layer of the color photographic light-sensitive material. Furthermore, a development accelerator, a developer, a silver halide solvent, a toning agent, a hardener, a fogging agent, an antifogging agent by coupling with a competitive coupler having an effect of color correction and an oxidized form of a developing agent. Compounds that release photographically useful fragments such as chemical sensitizers, spectral sensitizers and desensitizers can be used.
[0151]
The photosensitive material can be provided with auxiliary layers such as a filter layer, an antihalation layer, and an irradiation prevention layer. These layers and / or the emulsion layer may contain a dye which flows out of the photosensitive material or is bleached during the development process.
[0152]
Matting agents, lubricants, image stabilizers, formalin scavengers, ultraviolet absorbers, fluorescent brighteners, surfactants, development accelerators and development retarders can be added to the photosensitive material.
[0153]
As the support, paper laminated with polyethylene, polyethylene terephthalate film, baryta paper, cellulose triacetate, or the like can be used.
[0154]
【Example】
EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.
[0155]
Example 1
(1) Preparation of comparative emulsion Em-1
《Nucleation process》
While maintaining the following reaction mother liquor (Gr-1) in the reaction vessel at 30 ° C. and stirring with a mixing stirrer described in JP-A-62-160128 at a stirring speed of 400 rpm, 1N sulfuric acid was added. Was used to adjust the pH to 1.96. Thereafter, 178 ml of each of the (S-1) liquid and the (H-1) liquid was added at a constant flow rate for 1 minute using the double jet method to perform nucleation.
[0156]
(Gr-1)
Alkali-treated inert gelatin (average molecular weight 100,000) 40.50 g
Potassium bromide 12.40g
Finish with distilled water to 16.2L
(S-1)
862.5 g of silver nitrate
Finish to 4.06 L with distilled water
(H-1)
Potassium bromide 604.5g
Finish to 4.06 L with distilled water.
[0157]
《Aging process》
(G-1) liquid was added after completion | finish of the said nucleus formation process, and it heated up at 60 degreeC over 30 minutes. During this time, the silver potential of the emulsion in the reaction vessel (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a comparison electrode) was controlled to 6 mV using a 2N potassium bromide solution. Subsequently, an aqueous ammonia solution was added to adjust the pH to 9.3, and the pH was further maintained for 7 minutes, and then the pH was adjusted to 6.1 using an acetic acid aqueous solution. During this period, the silver potential was controlled at 6 mV using a 2N potassium bromide solution.
[0158]

Finish to 4.22 L with distilled water.
[0159]
<Grain growth process>
After completion of the aging step, the remaining (S-1) solution and the remaining (H-1) solution are subsequently accelerated using the double jet method while accelerating the flow rate (the ratio of the addition flow rate at the end to the start is about 12). Times), added in 37 minutes. (G-2) solution was added after the addition was completed, and the stirring rotation speed was adjusted to 550 rpm, and then (S-2) solution 2.11L and (H-2) solution were accelerated. (The ratio of the addition flow rate at the end to the start was about twice), and the addition was performed for 40 minutes. During this period, the silver potential of the emulsion was controlled at 6 mV using a 2N potassium bromide solution. After completion of the addition, the emulsion temperature in the reaction vessel was lowered to 40 ° C. over 15 minutes. Thereafter, the silver potential in the reaction vessel was adjusted to -39 mV (pBr1.29) using a 3N potassium bromide solution, and then 407.5 g of (K-1) solution was added, and then (S-2) The rest of the liquid and (H-3) liquid were added over 25 minutes while accelerating the flow rate (the ratio of the addition flow rate at the end to the start was about 1.2 times).
[0160]
(S-2)
Silver nitrate 2137.5g
Finish with distilled water to 3.60L
(H-2)
Potassium bromide 859.5g
Potassium iodide 24.45g
Finish to 2.11 L with distilled water
(H-3)
Potassium bromide 620.6g
Finish to 1.49L with distilled water
(G-2)
Ossein gelatin 284.9g
Compound EO (10% ethanol solution) 7.75 ml
Finish with distilled water to 1.93L
(K-1)
Potassium iodide 38.1g
Finish to 183.6 ml with distilled water.
[0161]
After completion of the grain growth, desalting was performed according to the method described in JP-A-5-72658, and then gelatin was added and dispersed, and the pH was adjusted to 5.80 and the pAg to 8.05 at 40 ° C. The emulsion thus obtained is designated Em-1.
[0162]
From the electron micrograph of the obtained emulsion grains, the grain size was 1.50 μm, the aspect ratio was 7.4 (50% of the total projected area), and the coefficient of variation of the grain size distribution was 15 The tabular grains were confirmed to be 0.0% and a grain thickness variation coefficient of 21.2%.
[0163]
(2) Preparation of comparative emulsion Em-2
In the preparation of Em-1, comparative emulsion Em was prepared in the same manner as Em-1, except that the temperature after the temperature drop of <Grain Growth Step> was 55 ° C. and the EAg adjustment value was subsequently set to −30 mV (pBr 1.29). -2 was prepared. As a result of observation with an electron microscope, it was confirmed that Em-2 is composed of particles having a particle size, an aspect ratio, a variation coefficient of particle size distribution, and a variation coefficient of particle thickness which are substantially the same as those of Em-1.
[0164]
(3) Preparation of comparative emulsion Em-3
A comparative emulsion Em-3 was prepared in the same manner as Em-1, except that in the preparation of Em-1, << grain growth step >> was performed as follows. As a result of observation with an electron microscope, it was confirmed that Em-3 is composed of particles having a particle size, an aspect ratio, a variation coefficient of particle size distribution, and a variation coefficient of particle thickness that are substantially the same as those of Em-1. FIG. 2 is a graph showing the slow continuous change of the silver iodide content in the grains of Em-3. FIG. 2 shows the silver iodide content of Em-3 at each point from the grain center to the grain edge. Apparently, the change in the silver iodide content from 640 nm to 690 nm from the center of the grain is abrupt, and the halogen deviates from the definition of the slow continuous change in the silver iodide content of the present invention at 0.2 mol% / nm or more. Silver halide grains.
[0165]
<Grain growth process>
After completion of the aging step, the remaining (S-1) solution and the remaining (H-1) solution are subsequently accelerated using the double jet method while accelerating the flow rate (the ratio of the addition flow rate at the end to the start is about 12). Times), added in 37 minutes. (G-2) solution was added after the addition was completed, and the stirring rotation speed was adjusted to 550 rpm, and then (S-3) solution 2.11L and (H-2) solution were accelerated. (The ratio of the addition flow rate at the end to the start was about twice), and the addition was performed for 40 minutes. During this period, the silver potential of the emulsion was controlled at 6 mV using a 2N potassium bromide solution. After completion of the addition, the emulsion temperature in the reaction vessel was lowered to 40 ° C. over 15 minutes. Thereafter, the silver potential in the reaction vessel was adjusted to −40 mV (pBr1.29) using a 3N potassium bromide solution, and then 407.5 g of (F-1) solution was added, and then (S-3). The rest of the liquid and (H-4) liquid were added over 25 minutes while accelerating the flow rate (the ratio of the addition flow rate at the end to the start was about 1.2 times).
[0166]
(S-3)
Silver nitrate 2098.5g
Finish with distilled water to 3.53L
(H-2)
Potassium bromide 859.5g
Potassium iodide 24.45g
Finish to 2.11 L with distilled water
(H-4)
Potassium bromide 591.5g
Finish with distilled water to 1.42L
(G-2)
Ossein gelatin 284.9g
Compound EO (10% ethanol solution) 7.75 ml
Finish with distilled water to 1.93L
(F-1)
Consists of 3% by weight gelatin and silver iodide grains (average grain size 0.05 μm)
Fine grain emulsion (*) 407.5g
* The preparation method is as follows: In 5000 ml of 6.0 wt% gelatin solution containing 0.06 mol potassium iodide, an aqueous solution containing 7.06 mol silver nitrate and 7.06 mol potassium iodide, respectively. 2000 ml was added over 10 minutes. During the fine particle formation, the pH was controlled at 2.0 using nitric acid, and the temperature was controlled at 40 ° C. After the particle formation, the pH was adjusted to 6.0 using an aqueous sodium carbonate solution. The finished weight was 12.53 kg.
[0167]
(4) Preparation of comparative emulsion Em-4
In the preparation of Em-3, comparative emulsion Em was prepared in the same manner as Em-3, except that the temperature after the temperature drop in <Grain growth step> was 55 ° C. and the subsequent EAg adjustment value was −30 mV (pBr1.29). -4 was prepared. As a result of observation with an electron microscope, it was confirmed that Em-4 is composed of particles having a particle size, an aspect ratio, a variation coefficient of particle size distribution, and a variation coefficient of particle thickness that are substantially the same as those of Em-1.
[0168]
(5) Preparation of the present emulsion Em-5
In preparing Em-1, Emulsion of the present invention Em-5 was prepared in the same manner as Em-1, except that the << Grain growth step >> was changed as follows. As a result of observation with an electron microscope, it was confirmed that Em-5 is composed of particles having a particle size, an aspect ratio, a variation coefficient of particle size distribution, and a variation coefficient of particle thickness which are substantially the same as those of Em-1. FIG. 3 is a graph showing a slow continuous change in the silver iodide content in the grains of Em-5. FIG. 3 shows the silver iodide content of Em-5 at each point from the grain center to the grain edge. Apparently, the change in silver iodide content is small in any region of the grain, and the silver halide grain satisfies the definition of 0.03 mol% / nm of the slow continuous change in silver iodide content of the present invention.
[0169]
<Grain growth process>
After completion of the aging step, the remaining (S-1) solution and the remaining (H-1) solution are subsequently accelerated using the double jet method while accelerating the flow rate (the ratio of the addition flow rate at the end to the start is about 12). Times), added in 37 minutes. (G-2) solution was added after the addition was completed, and the stirring rotation speed was adjusted to 550 rpm, and then (S-2) solution 2.11L and (H-2) solution were accelerated. (The ratio of the addition flow rate at the end to the start was about twice), and the addition was performed for 40 minutes. During this period, the silver potential of the emulsion was controlled at 6 mV using a 2N potassium bromide solution. After completion of the addition, the emulsion temperature in the reaction vessel was lowered to 40 ° C. over 15 minutes. Thereafter, a solution (Z-1) containing an iodine ion releasing agent and a solution (SS-1) containing a nucleophile were added, and the pH was adjusted to 9.3 using an aqueous potassium hydroxide solution. Iodine ion releasing reaction was performed while aging for 4 minutes, and then the pH was adjusted to 5.0 using an acetic acid solution. Thereafter, the silver potential in the reaction vessel was adjusted to −40 mV (pBr1.29) using a 3N potassium bromide solution, and then 407.5 g of (F-1) solution was added, and then (S-2). The rest of the liquid and (H-3) liquid were added over 25 minutes while accelerating the flow rate (the ratio of the addition flow rate at the end to the start was about 1.2 times).
[0170]
(S-2)
Silver nitrate 2137.5g
Finish with distilled water to 3.60L
(H-2)
Potassium bromide 859.5g
Potassium iodide 24.45g
Finish to 2.11 L with distilled water
(H-3)
Potassium bromide 620.6g
Finish to 1.49L with distilled water
(G-2)
Ossein gelatin 284.9g
Compound EO (10% ethanol solution) 7.75 ml
Finish with distilled water to 1.93L
(Z-1)
Sodium p-iodoacetamidobenzenesulfonate 83.4g
Finish to 1.0L with distilled water
(SS-1)
Sodium sulfite 28.9g
Finish to 0.3 L with distilled water.
[0171]
(6) Preparation of comparative emulsion Em-6
Em-5 was prepared in the same manner as Em-5, except that the temperature after the temperature drop in <Grain growth step> was 55 ° C. and the EAg adjustment value following the iodine ion release reaction was −30 mV (pBr1.29). Comparative emulsion Em-6 was prepared. As a result of observation with an electron microscope, it was confirmed that Em-6 is composed of particles having a particle size, an aspect ratio, a variation coefficient of particle size distribution, and a variation coefficient of particle thickness that are substantially the same as those of Em-1.
[0172]
(7) Preparation of the present emulsion Em-7
In the preparation of Em-5, the (Z-2) liquid and the (SS-2) liquid were used in place of the (Z-1) liquid and the (SS-1) liquid in << particle growth step >>, respectively. In the same manner as E-5, Emulsion Em-7 of the present invention was prepared. As a result of observation with an electron microscope, it was confirmed that Em-7 is composed of particles having a particle size, an aspect ratio, a variation coefficient of particle size distribution, and a variation coefficient of particle thickness which are substantially the same as those of Em-1.
[0173]
(Z-2)
57.7 g of sodium p-iodoacetamidobenzenesulfonate
Finish to 1.0L with distilled water
(SS-2)
Sodium sulfite 20.0g
Finish to 0.3 L with distilled water.
[0174]
(8) Preparation of comparative emulsion Em-8
In the preparation of Em-1, Comparative Emulsion Em-8 was prepared in the same manner as Em-1, except that (K-1) solution addition in << Grain Growth Step >> was not performed. As a result of observation with an electron microscope, it was confirmed that Em-8 was composed of particles having a particle size, an aspect ratio, a variation coefficient of particle size distribution, and a variation coefficient of particle thickness that were substantially the same as those of Em-1.
[0175]
(9) Chemical sensitization / spectral sensitization treatment of each emulsion
The following sensitizing dyes SSD-1, SSD-2, and SSD-3 were added while maintaining the emulsions Em-1 to Em-8 at 52 ° C. After aging for 20 minutes, sodium thiosulfate was added, and chloroauric acid and potassium thiocyanate were further added. After ripening to obtain optimum sensitivity for each emulsion-fogging, 1-phenyl-5-mercaptotetrazole and 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene were added. And stabilized. The amount of sensitizing dye, sensitizer and stabilizer added to each emulsion and the ripening time were set so that the sensitivity-fogging relationship at the time of 1/200 second exposure was optimized.
[0176]
(10) Preparation / evaluation of coated sample
Dispersion, extender, emulsified and dispersed in an aqueous solution containing gelatin obtained by dissolving the following coupler MCP-1 in ethyl acetate and tricresyl phosphate in each emulsion of Em-1 to Em-8 subjected to sensitization treatment A general photographic additive such as a hardener is added to prepare a coating solution, which is coated on a subbed cellulose triacetate film support according to a conventional method and dried to obtain a color photosensitive material sample No. 101-No. 108 was produced.
[0177]
[Formula 4]

[0178]
Immediately after these samples were prepared, each sample was subjected to wedge exposure through a Toshiba glass filter (Y-48) using a light source having a color temperature of 5400 ° K, and developed according to the following processing steps.
[0179]

[0180]
The following were used as the color developer, bleaching solution, fixing solution, stabilizing solution and replenisher.
[0181]

Add water to make 1 liter, and adjust the color developer to pH 10.06 and the replenisher to pH 10.18 using potassium hydroxide or 20% sulfuric acid.
[0182]

Add water to make 1 liter, and use aqueous ammonia or glacial acetic acid to adjust the bleaching solution to pH 4.4 and the replenisher to pH 4.0.
[0183]

Use ammonia water or glacial acetic acid to adjust the fixing solution to pH 6.2 and the replenisher to pH 6.5, and then add water to make 1 liter.
[0184]

After adding water to 1 liter, the pH is adjusted to 8.5 using aqueous ammonia or 50% sulfuric acid.
[0185]
The sensitivity and fog of the obtained sample were measured using green light. The measurement method and conditions are shown below.
[0186]
For the relative sensitivity, the reciprocal of the exposure amount giving the density of the minimum density (Dmin) +0.2 in each sample is obtained as the sensitivity. The sensitivity is shown as a relative value with a sensitivity of 108 as 100. A larger value of relative sensitivity means higher sensitivity and better sensitivity.
[0187]
The increase in fog due to pressure is measured by measuring the amount of increase in the density of the unexposed area where the load is applied. A relative value (ΔDp1) in which the amount of increase in concentration of 108 is 100 is shown (the smaller this value, the smaller the increase in fog due to pressure, and the better the pressure resistance). The decrease in sensitivity due to the pressure is measured by measuring the amount of decrease in concentration at the portion where the load is applied in the concentration portion of (Dmax−Dmin) / 2. A relative value (ΔDp2) in which the density reduction amount of 108 is 100 is shown (the smaller this value, the smaller the sensitivity reduction due to pressure, and the better the pressure resistance).
[0188]
As an evaluation of suitability for development processing, the color development processing time in the processing step was shortened to 2 minutes and 50 seconds, and the sensitivity deterioration width from the development of 3 minutes and 15 seconds was measured as Sample No. ΔS was expressed as a relative value with the value of 108 as 100.
[0189]
The results of the evaluation of emulsion characteristics are shown in Tables 1 and 2.
[0190]
(11) Observation of dislocation line ratio and silver iodide outline / measurement of silver iodide content change
Each emulsion was diluted 5 times with ultrapure water and then centrifuged, and the precipitate was redispersed in ultrapure water. The solution was dropped onto 200 mesh with a carbon support film that had been subjected to a hydrophilic treatment, and the excess dispersion was removed with a spin coater. Using a transmission electron microscope TEM2000FX, after photographing about 700 particles at an acceleration voltage of 200 kV, a measurement temperature of −130 ° C., and a direct magnification of × 8000 to × 10000, 30 or more particles per particle in the fringe portion. The ratio of grains having dislocation lines and grains having a silver iodide outline to the total grain projected area was determined. An example of an electron micrograph of tabular grains having a silver iodide outline is shown in FIG.
[0191]
Further, using the same sample and apparatus, the change in silver iodide content from the grain center to the grain edge by EPMA (TEM-EDS method) was measured. Measure acceleration of 200 kV, measurement temperature of -130 ° C., measurement spot diameter of 20 nm, integration time of 50 seconds, and measure 16 points on the straight line from the center of the particle to the end of the particle. The change in silver content was measured, and the ratio of the particles having a change rate of −0.03 mol% / nm to +0.03 mol% / nm to the total grain projected area was determined. The results are shown in Tables 1 and 2.
[0192]
[Table 1]

[0193]
[Table 2]

[0194]
Example 2
(1) Preparation of emulsion Em-9 of the present invention
Emulsion of the present invention Em-9 was prepared in the same manner as Em-7 except that the ripening step was changed as follows in the preparation of emulsion Em-7.
[0195]
《Aging process》
(G-1) liquid was added after completion | finish of the said nucleus formation process, and it heated up at 60 degreeC over 30 minutes. During this time, the silver potential of the emulsion in the reaction vessel (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a comparison electrode) was controlled to 6 mV using a 2N potassium bromide solution. Stirring was continued for 15 minutes, and then the pH was adjusted to 6.1 using potassium hydroxide. During this period, the silver potential was controlled at 6 mV using a 2N potassium bromide solution.
[0196]
From the electron micrographs of the obtained emulsion grains, the grain size was 1.53 μm, the aspect ratio was 7.3 (50% of the total projected area), and the coefficient of variation in grain size distribution was 28. The tabular grains were confirmed to be 0.0% and a grain thickness distribution coefficient of variation of 37.4%. The dislocation line grain ratio, the silver iodide content rate, the slowly changing grain ratio, and the silver iodide contour grain ratio were 76%, 91%, and 9%, respectively.
[0197]
(2) Evaluation of emulsion
A sample 109 using Em-9 was prepared in the same manner as (9) onward in Example 1, and the same evaluation as in Example 1 was performed. The results are shown in Table 3. It can be seen that the effect of the present invention is remarkable in an emulsion having a narrow particle size distribution and thickness distribution.
[0198]
Example 3
(1) Preparation of emulsion Em-10 of the present invention
In the preparation of Emulsion Em-7, after completion of the addition of the (S-1) solution in the grain growth step, the (R-1) solution was added as a rush and before the temperature was lowered to 40 ° C., the (T-1) solution was added. Emulsion of the present invention Em-10 was prepared in the same manner as Em-7, except that the temperature was lowered after the rush addition. From the electron micrograph of the obtained emulsion grains, it was confirmed that the grains were almost the same as Em-1.
[0199]
(R-1)
Thiourea dioxide 26.6mg
46.6 ml of distilled water
(T-1)
Sodium ethanethiosulfonate 880.1mg
293.4 ml of distilled water.
[0200]
(2) Preparation of the present emulsion Em-11
After grain growth and desalting in the same manner as in Em-10, gelatin was added and dispersed, the emulsion temperature was adjusted to 50 ° C., (F-2) solution was added and ripened for 20 minutes. . Thereafter, the temperature was lowered to 40 ° C., and the pH was adjusted to 5.80 and the pAg was adjusted to 8.06. The emulsion thus obtained is named Emulsion Em-11 of the present invention.
[0201]
(F-2)
K₂IrCl₆Made of silver bromide grains doped with (average particle size 0.05 μm)
Fine grain emulsion (*) 4.70 g
* Preparation of fine grain emulsion F-2 is as follows: 5000 ml of a 6.0 wt% gelatin solution containing 0.06 mol of potassium bromide, 2000 ml of an aqueous solution containing 7.06 mol of silver nitrate, and 7.06 Molar potassium bromide and 4.4 × 10^-3Mole K₂IrCl₆2000 ml of an aqueous solution containing was added over 10 minutes. During the fine particle formation, the pH was controlled at 2.0 using nitric acid, and the temperature was controlled at 40 ° C. After the particle formation, the pH was adjusted to 6.0 using an aqueous sodium carbonate solution. The finished weight was 12.53 kg.
[0202]
(3) Preparation of comparative emulsion Em-12
In the preparation of emulsion Em-1, as in Em-10, in the grain growth step, after the addition of (S-1) solution was completed, (R-1) solution was added as a rush and before the temperature was lowered to 40 ° C., Comparative emulsion Em-12 was prepared in the same manner as Em-1, except that (T-1) solution was added as a rush and then the temperature was lowered. From the electron micrograph of the obtained emulsion grains, it was confirmed that the grains were almost the same as Em-1.
[0203]
(4) Preparation of comparative emulsion Em-13
After grain growth and desalting in the same manner as in Em-12, gelatin was added and dispersed, the emulsion temperature was adjusted to 50 ° C., (F-2) solution was added, and ripened for 20 minutes. . Thereafter, the temperature was lowered to 40 ° C., and the pH was adjusted to 5.80 and the pAg was adjusted to 8.06. The emulsion thus obtained is designated as comparative emulsion Em-13. In addition, all of Em-10 to 13 had the same particle size, aspect ratio, variation coefficient of particle size distribution, and variation coefficient of particle thickness as Em-1.
[0204]
(5) Evaluation of emulsion
Samples 110 to 113 using Em-10 to 13 were prepared in the same manner as (9) onward in Example 1, and the same evaluation as in Example 1 was performed. The results are shown in Table 3. It can be seen that the emulsion of the present invention has a synergistic effect with reduction sensitization and metal doping.
[0205]
[Table 3]

[0206]
Example 4
On the triacetyl cellulose film support subjected to the subbing treatment, each layer having the composition as shown below was sequentially formed from the support side. A multilayer color photographic light-sensitive material 407 was prepared using Em-7 in which chemical sensitization / spectral sensitization was applied to the high-sensitivity green color-sensitive layer.
[0207]
Addition amount is 1m²Expressed in grams per unit. However, silver halide and colloidal silver were converted to the amount of silver, and sensitizing dye (indicated by SD) was shown in moles per mole of silver.
[0208]
First layer (Anti-halation layer)
Black colloidal silver 0.16
UV-1 0.3
CM-1 0.123
CC-1 0.044
OIL-1 0.167
Gelatin 1.33
Second layer (intermediate layer)
AS-1 0.160
OIL-1 0.20
Gelatin 0.69
Third layer (low sensitivity red color sensitive layer)
Silver iodobromide a 0.20
Silver iodobromide b 0.29
SD-1 2.37 × 10^-Five
SD-2 1.2 × 10^-Four
SD-3 2.4 × 10^-Four
SD-4 2.4 × 10^-6
C-1 0.32
CC-1 0.038
OIL-2 0.28
AS-2 0.002
Gelatin 0.73
4th layer (medium sensitivity red color sensitive layer)
Silver iodobromide c 0.10
Silver iodobromide d 0.86
SD-1 4.5 × 10^-Five
SD-2 2.3 × 10^-Four
SD-3 4.5 × 10^-Four
C-2 0.52
CC-1 0.06
DI-1 0.047
OIL-2 0.46
AS-2 0.004
Gelatin 1.30
5th layer (high sensitivity red color sensitive layer)
Silver iodobromide c 0.13
Silver iodobromide d 1.18
SD-1 3.0 × 10^-Five
SD-2 1.5 × 10^-Four
SD-3 3.0 × 10^-Four
C-2 0.047
C-3 0.09
CC-1 0.036
DI-1 0.024
OIL-2 0.27
AS-2 0.006
Gelatin 1.28
6th layer (intermediate layer)
OIL-1 0.29
AS-1 0.23
Gelatin 1.00
7th layer (low sensitivity green color sensitive layer)
Silver iodobromide a 0.19
Silver iodobromide b 0.062
SD-4 3.6 × 10^-Four
SD-5 3.6 × 10^-Four
M-1 0.18
CM-1 0.033
OIL-1 0.22
AS-2 0.002
AS-3 0.05
Gelatin 0.61
8th layer (intermediate layer)
OIL-1 0.26
AS-1 0.054
Gelatin 0.80
9th layer (medium sensitive green color sensitive layer)
Silver iodobromide e 0.54
Silver iodobromide f 0.54
SD-6 3.7 × 10^-Four
SD-7 7.4 × 10^-Five
SD-8 5.0 × 10^-Five
M-1 0.17
M-2 0.33
CM-1 0.024
CM-2 0.029
DI-2 0.024
DI-3 0.005
OIL-1 0.73
AS-3 0.035
AS-2 0.003
Gelatin 1.80
10th layer (high sensitivity green color sensitive layer)
Em-7 1.19
M-1 0.065
CM-2 0.026
CM-1 0.022
DI-3 0.003
DI-2 0.003
OIL-1 0.19
OIL-2 0.43
AS-3 0.017
AS-2 0.014
Gelatin 1.23
11th layer (yellow filter layer)
Yellow colloidal silver 0.05
OIL-1 0.18
AS-1 0.16
Gelatin 1.00
12th layer (low sensitivity blue color sensitive layer)
Silver iodobromide b 0.22
Silver iodobromide a 0.08
Silver iodobromide g 0.09
SD-9 6.5 × 10^-Four
SD-10 2.5 × 10^-Four
Y-1 0.77
DI-4 0.017
OIL-1 0.31
AS-2 0.002
Gelatin 1.29
13th layer (high sensitivity blue color sensitive layer)
Silver iodobromide g 0.41
Silver iodobromide h 0.61
SD-9 4.4 × 10^-Four
SD-10 1.5 × 10^-Four
Y-1 0.23
OIL-1 0.10
AS-2 0.004
Gelatin 1.20
14th layer (first protective layer)
Silver iodobromide i 0.30
UV-1 0.055
UV-2 0.110
OIL-2 0.30
Gelatin 1.32
15th layer (second protective layer)
PM-1 0.15
PM-2 0.04
WAX-1 0.02
D-1 0.001
Gelatin 0.55
The characteristics of the silver iodobromide are shown below (the average grain size of the emulsion below is the length of a side of a cube having the same volume).
[0209]

As typical examples of forming silver halide grains of the present invention, production examples of silver iodobromide d and f are shown below. Further, silver iodobromide a, b, c, e, g, h, and i conform to the production examples of silver iodobromide d and f. First, seed crystal emulsion-1 was prepared.
[0210]
Preparation of seed crystal emulsion-1
A seed crystal emulsion was prepared as follows.
[0211]
Using a mixing stirrer shown in Japanese Patent Publication Nos. 58-58288 and 58-58289, an aqueous silver nitrate solution (1.161 mol), potassium bromide and potassium iodide were added to the following solution A-11 adjusted to 35 ° C. A mixed aqueous solution (potassium iodide 2 mol%) was added over 2 minutes by the simultaneous mixing method while maintaining the silver potential (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a comparison electrode) at 0 mV, Nucleation was performed. Subsequently, the temperature of the solution was increased to 60 ° C. over a period of 60 minutes, and the pH was adjusted to 5.0 with an aqueous sodium carbonate solution. Then, an aqueous silver nitrate solution (5.902 mol), potassium bromide and iodide were used. A mixed aqueous solution of potassium (potassium iodide 2 mol%) was added over 42 minutes by the simultaneous mixing method while maintaining the silver potential at 9 mV. After completion of the addition, the solution was immediately desalted and washed with water using a normal flocculation method while lowering the temperature to 40 ° C.
[0212]
The obtained seed crystal emulsion has an average sphere equivalent diameter of 0.24 μm, an average aspect ratio of 4.8, 90% or more of the total projected area of the silver halide grains is a maximum side length ratio (the maximum side length of each grain and The emulsion was made of hexagonal tabular grains having a ratio of 1.0 to 2.0. This emulsion is referred to as seed crystal emulsion-1.
[0213]

Preparation of silver iodide fine grain emulsion SMC-1
While vigorously stirring 5 liters of a 6.0 wt% gelatin aqueous solution containing 0.06 mol potassium iodide, 7.06 mol silver nitrate aqueous solution and 7.06 mol potassium iodide aqueous solution, 2 liters each for 10 minutes. Was added as needed. During this time, the pH was controlled at 2.0 using nitric acid, and the temperature was controlled at 40 ° C. After the particle preparation, the pH was adjusted to 5.0 using an aqueous sodium carbonate solution. The average grain size of the obtained silver iodide fine particles was 0.05 μm. This emulsion is designated as SMC-1.
[0214]
Preparation of silver iodobromide d
0.178 mol equivalent of seed crystal emulsion-1 and HO (CH₂CH₂O)_m(CH (CH_Three) CH₂O)_19.8(CH₂CH₂O)_n700 ml of a 4.5 wt% inert gelatin aqueous solution containing 0.5 ml of 10% ethanol solution of H (m + n = 9.77) was maintained at 75 ° C., and pAg was adjusted to 8.4 and pH was adjusted to 5.0. Thereafter, particles were formed by the following procedure by a simultaneous mixing method with vigorous stirring.
[0215]
1) A 3.093 mol silver nitrate aqueous solution, 0.287 mol SMC-1 and an aqueous potassium bromide solution were added while maintaining the pAg at 8.4 and the pH at 5.0.
[0216]
2) Subsequently, the solution was cooled to 60 ° C., and pAg was adjusted to 9.8. Thereafter, 0.071 mol of SMC-1 was added, and aging was performed for 2 minutes (introduction of dislocation lines).
[0217]
3) 0.959 mol silver nitrate aqueous solution, 0.03 mol SMC-1 and potassium bromide aqueous solution were added while maintaining pAg at 9.8 and pH at 5.0.
[0218]
It should be noted that each solution was added at an optimum rate so that the formation of new nuclei and the Ostwald ripening between the particles did not progress through the formation of particles. After completion of the above addition, a water washing treatment was performed at 40 ° C. using a normal flocculation method, and then gelatin was added and redispersed to adjust pAg to 8.1 and pH to 5.8.
[0219]
The obtained emulsion had a grain size (one side length of a cube having the same volume) of 0.74 μm, an average aspect ratio of 5.0, and a silver iodide content of 2 / 8.5 / X / 3 mol% (X is from the inside of the grain). The emulsion was composed of tabular grains having a halogen composition at the dislocation line introduction position. When this emulsion was observed with an electron microscope, 5 or more dislocation lines were observed both in the fringe portion and in the inside of the grain in grains of 60% or more of the total projected area of grains in the emulsion. The surface silver iodide content was 6.7 mol%.
[0220]
Preparation of silver iodobromide f
In the preparation of silver iodobromide d, pAg was 8.8 in step 1), the amount of silver nitrate added was 2.077 mol SMC-1 was 0.218 mol, and silver nitrate added in step 3) Silver iodobromide f was prepared in exactly the same manner as silver iodobromide d except that the amount was 0.91 mol and the amount of SMC-1 was 0.079 mol.
[0221]
The obtained emulsion had a grain size (one side length of a cube having the same volume) of 0.65 μm, an average aspect ratio of 6.5, and a silver iodide content of 2 / 9.5 / X / 8.0 mol% from the inside of the grain ( X was an emulsion composed of tabular grains having a halogen composition at the dislocation line introduction position. When this emulsion was observed with an electron microscope, 5 or more dislocation lines were observed both in the fringe portion and in the inside of the grain in grains of 60% or more of the total projected area of grains in the emulsion. The surface silver iodide content was 11.9 mol%.
[0222]
Add the above-mentioned sensitizing dyes to each of the above emulsions and ripen them, then add triphosphine selenide, sodium thiosulfate, chloroauric acid, and potassium thiocyanate so that the fogging and sensitivity relationships are optimized according to conventional methods. Chemical sensitization was applied.
[0223]
Further, silver iodobromide a, b, c, e, g, h, and i were subjected to spectral sensitization and chemical sensitization according to a conventional method.
[0224]
In addition to the above-mentioned composition, coating aids SU-1, SU-2, SU-3, dispersion aid SU-4, viscosity modifier V-1, stabilizers ST-1, ST-2, fog Two types of polyvinylpyrrolidone (AF-2), inhibitor AF-1, weight average molecular weight: 10,000 and weight average molecular weight: 1,100,000, inhibitors AF-3, AF-4, AF-5, hard Filming agents H-1, H-2 and preservative Ase-1 were added.
[0225]
The structure of the compound used for the sample is shown below.
[0226]
[Chemical formula 5]

[0227]
[Chemical 6]

[0228]
[Chemical 7]

[0229]
[Chemical 8]

[0230]
[Chemical 9]

[0231]
[Chemical Formula 10]

[0232]
Embedded image

[0233]
Embedded image

[0234]
Embedded image

[0235]
Thus, a sample 407 of the photosensitive material was prepared. Similarly, a multilayer color photographic light-sensitive material 401 using Em-1 was prepared, 411 using Em-11, and 413 using Em-13, and the same evaluation as in Example 1 was performed. Similar results to the single emulsion layer samples of Tables 1, 2 and 3 were obtained. The results are shown in Table 4.
[0236]
[Table 4]

[0237]
【The invention's effect】
According to the present invention, it was possible to provide a silver halide photographic emulsion having high sensitivity, pressure resistance, and development processing suitability.
[Brief description of the drawings]
FIG. 1 is an electron micrograph of silver halide grains having a silver iodide outline according to the present invention.
FIG. 2 is a graph showing a slow continuous change state of silver iodide content in grains of a comparative silver halide emulsion Em-3.
FIG. 3 is a graph showing a slow continuous change in the silver iodide content in the grains of the silver halide emulsion Em-5 of the present invention.

Claims (7)

  30% or more of the projected area of all silver halide grains has an aspect ratio of 5 or more, has 30 or more dislocation lines per grain in the fringe part, and iodine from the grain center toward the grain edge. A silver halide photographic emulsion comprising tabular silver halide grains whose silver halide content changes slowly and continuously. More than 50% of the projected area of all silver halide grains are tabular silver halide grains having an aspect ratio of 5 or more, and more than 50% of the projected area of all silver halide grains is 30 per grain in the fringe portion. These are tabular silver halide grains having the above dislocation lines, and more than 50% of the projected area of all silver halide grains has a continuous low silver iodide content from the grain center to the grain edge. the silver halide photographic emulsion characterized that you contain changes to tabular silver halide grains. More than 50% of the projected area of all silver halide grains are tabular silver halide grains having an aspect ratio of 5 or more, and more than 50% of the projected area of all silver halide grains is 30 per grain in the fringe portion. The tabular silver halide grains having the above dislocation lines, and the tabular grains having a silver iodide outline contain tabular silver halide grains having a projected area of 20% or less of the total silver halide grains . 3. The silver halide photographic emulsion according to claim 2, wherein 4. The variation coefficient of grain size distribution of all silver halide grains is 25% or less, and the variation coefficient of grain thickness distribution is 35% or less. Silver halide photographic emulsion . 5. The silver halide photographic emulsion according to claim 1, which has 30 or more dislocation lines per grain limited to the fringe portion only. 6. The silver halide photographic emulsion according to claim 1, wherein at least a part of the tabular silver halide grains has a reduction sensitization center inside the grains. The silver halide photograph according to any one of claims 1 to 6, wherein at least a part of the tabular silver halide grains contains at least one polyvalent metal compound in a fringe portion of the grains. Emulsion .

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