Preparation of photographic silver halide emulsions utilizing polyoxalkylenated gelating derivatives
Abstract
Abstract 1,130,610. Preparing silver halide emulsions. GENERAL ANILINE & FILM CORP. Nov. 23, 1965 [Nov. 27, 1964], No. 49749/65. Heading G2C. Silver halide emulsions are obtained by mixing an aqueous solution of a water-soluble silver salt and an aqueous solution of one or more water-soluble halides in the presence of an aqueous solution of a water-soluble polyoxyalkylenated derivative of gelatine, flocculating the resulting mixture and separating the flocculate. The flocculate may be washed and redispersed in gelatine. The polyoxyalkylented derivatives of gelatine are obtained by reacting gelatine with an alkylene or substituted alkylene oxide e.g. ethylene oxide, propylene oxide, butylene oxide, styrene oxide and cyclohexene oxide. The emulsion may be digestedbefore flocculation and flocculated by simply lowering pH 1 for example with acid ammonium sulphate, or by adding flocculating agents e.g. alkyl sulphonic acids or poly (styrene sulphonic acid).
Inventors
- 👤 Fritz Dersch
- 👤 Sally L Paniccia
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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