Ammonia → Silver laurate

Participants

Reaction Steps

To a solution of 11 g of lauric acid in 100 ml of butyl acetate kept at 10°C was added 100 ml of a dilute aqueous solution of nitric acid (25°C, pH = 2.0) with stirring, and 50 ml of an aqueous solution of silver ammonium complex [this salt can be represent by the formula [Ag (NH3)2 ]+NO3 -; from 1 molar Ag NO3 and 2 molar NH3 (used as NH4OH)] containing 8.5 g of silver nitrate (cooled at 0°C) was then added over a 1 minute period to react the laurate and silver ions, thus obtaining crystals of silver laurate in a spindle shape of about 1 micron (long side) by about 0.05 micron (short side). The thus obtained silver salt was washed with water and methanol and 2.7 g of it was ball-milled with 3.0 g of polyvinyl butyral (average degree of polymerization 1,000; index of refraction 1.47-1.49; heat resistant to about 115°F) and 20 ml of isopropyl alcohol to prepare a polymer dispersion of the silver salt. An effective amount of 1, 3 dibromo-5,5-dimethylhydantoin (2.5 weight percent methyl cellosolve solution) was added thereto (1 ml) as an anti-heat fogging agent, 1 ml of a 2.5 weight percent methanol solution of ammonium bromide was added (silver halide forming agent) and 5 ml of a 0.0025 weight percent chloroform solution of the following light-sensitive dye was added thereto: ##SPC1##

Provenance & Evidence