Docosanoic Acid → Silver behenate

Participants

Reaction Conditions

Reaction Steps

10.6 Grams of behenic acid is mixed with 300 ml of distilled water at 90° C. for 15 minutes, and to the mixture was added 31.1 ml of a 1N sodium hydroxide aqueous solution over a period of 15 minutes with vigorous stirring. The mixture was allowed to stand for 1 hour and cooled to 30° C. Then, 7 ml of a 1N phosphorus acid aqueous solution was added, and to the mixture was further added 0.13 g of the following compound C-1 with vigorous stirring. Then, the silver halide grains C were added in such an amount that the amount of the silver halide became 1.25 mmol. Further, 25 ml of a 1N silver nitrate aqueous solution was continuously added over a period of 2 minutes, and the mixture was stirred for 90 minutes. To the aqueous mixture was added 37 g of a 1.2 wt. % butyl acetate solution of polyvinyl acetate to form flocs in the dispersion, and then water is removed. Thereafter, washing with water and removal of water were further performed twice. Then, 20 g of a 2.5 wt. % solution of polyvinyl butyral (Denka Butyral #3000-K, Denki Kagaku Kogyo K.K.) in a mixed solvent (butyl acetate/isopropyl alcohol=1/2 by volume) was added with stirring. To the resulting gel mixture of organic acid and silver halide, 7.8 g of polyvinyl butyral (Denka Butyral #4000-2, Denki Kagaku Kogyo K.K.) and 57 g of 2-butanone were added, followed by dispersing with a homogenizer, to obtain a silver behenate emulsion containing needle grains (average minor axis: 0.06 μm, average major axis: 1 μm, coefficient of variation: 30%). ##STR14## Preparation of Coating Solution C for Forming Light-sensitive Layer

Provenance & Evidence