Konishiroku Photo Industry Co., Ltd.

Hiroaki Shiozawa

Akio Suzuki

Takeo Koitabashi

Syoji Matsuzaka

Mikio Kawasaki

Hideki Takiguchi

Yoshihiro Haga

Kouji Ono

Kakujulo Fukuouji

There is disclosed a light-sensitive silver halide photographic material having at least one silver halide emulsion layer on a support, which comprises the light-sensitive photographic material contains light-sensitive silver halide grains, metal salt grains having internal fog and a polyhydric alcohol having at least two hydroxyl groups having a melting point of 40.degree. C. or higher.

Light-sensitive silver halide photographic material

There is disclosed a method for preparing a silver halide photographic emulsion by use of an ammoniacal silver nitrate solution in a double-jet manner, characterized in that the method comprises the step of maintaining the ratio between the maximum and minimum solubility of the silver halide in a silver halide photographic emulsion at 3 or less after 1/10 of the total amount of the solution containing silver halide has been used. The method according to the present invention provides a monodispersed silver halide photographic emulsion which has a high sensitivity, i.e., which comprises silver halide having a relatively large crystal size.

Method for preparing silver halide photographic emulsion

A silver halide photographic emulsion characterized in that it comprises silver halide grains which are reduction-sensitized during the process of growing said grains and containing a compound of the formula ##STR1## wherein R.sub.1 and R.sub.2 are selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an acyl group and a cycloalkyl group and R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkoxy group, an acyl group, a carboxyl group, an aldehyde group, an amino group, a sulfo group, an alkylthio group, an acylamino group, an aryloxy group, an arylthio group, an alkylamino group, an alkoxycabonyl group and a sulfonamide group. The emulsion exhibits both high sensitivity and improved stability as compared with prior art compositions.

Silver halide photographic emulsion

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Hino, Japan

Hiroaki Shiozawa