| 摘要 |
PURPOSE:To prevent the increase of fog and the lowering of sensitivity during storage by adding a soln. of a water soluble silver salt and a soln. of a water soluble halide to a soln. contg. protective colloid, coagulating formed silver halide particles together with the colloid with a polymer coagulant, removing dissolved matter and using the resulting silver halide emulsion. CONSTITUTION:A high molecular compd. consisting of A and B chains represented by formula I is used as the above-mentioned polymer coagulant. In the formula I, each of R1 and R2 is an aliphatic group, R3 is H, an aliphatic group, aryl or aralkyl, X is -O- or -NH-, M<+> is a cation, n=10-10<4>, any of two bonding radicals in the B chain may bond to tert. carbon having R1 and R2 in the A chain, and when X is -NH-, an N-contg. ring may be formed in combination with R3. The high molecular compd. has 3X10<3>-2X10<5> mol. wt. and is preferably added in 1/40-1/10 weight ratio to the protective colloid. |
