Ammonia → Silver behenate

Beteiligte Stoffe

Reaktionsschritte

3.4 g of silver behenate was dissolved in 100 ml of toluene at 60° C. 100 ml of a diluted aqueous solution of nitric acid having a pH of 2.0 (25° C.) was mixed with this solution while stirring the solution with a stirrer. The mixture was stirred at 60° C. and 100 ml of an aqueous solution of silver ammonium complex salt which was prepared by adding an ammonia solution to about 80 ml of an aqueous solution containing 1.7 g of silver nitrate and adding water to make the total volume 100 ml and then 50 ml of an aqueous solution containing 0.047 g of ammonium bromide and 0.001 g of ammonium iodide were added thereto at the same time while stirring the solution. Thus silver behenate and silver iodobromide were formed at the same time. When the reaction product was allowed to stand for 20 minutes at room temperature, it separated into an aqueous phase and a toluene phase. After removal of the aqueous phase, the toluene phase was washed with 400 ml of fresh water by decantation. This washing treatment was repeated three times. Then 400 ml of water was added thereto and silver behenate - silver iodobromide was separated by centrifugal separation. Thus 4 g of a mixture wherein spindle shaped silver behenate crystals having a length of about 1 micron and a diameter of about 0.05 microns contacted with silver iodobromide was produced. 2.5 g of this silver behenate-silver iodobromide mixture was added to 20 ml of an isopropyl alcohol solution containing 2 g of polyvinyl butyral and the mixture was ball milled for 1 hour to produce a polymer dispersion.

Herkunft & Nachweise