METHOD FOR PRODUCING SILVER CORE-GOLD SHELL FINE PARTICLE PROTECTED BY NON-WATER-SOLUBLE POLYMERIC PIGMENT-DISPERSING AGENT

PROBLEM TO BE SOLVED: To provide a method for producing re-dispersible composite metal fine particles of silver-gold, having a similar optical characteristics to the gold, simply, in good productivity and at a low cost. SOLUTION: This silver core-gold shell fine particles 10 having a constitution of covering the silver fine particles 2 with gold fine particles 3 and enclosing the surroundings of them with a non-water-soluble polymeric pigment-dispersing agent 4 is obtained by performing the reducing reaction of auric ions at the interface of (a) a silver fine particle-dispersed solution obtained by dispersing silver fine particles protected by the non-water-soluble polymeric pigment-dispersing agent in an organic solvent without having compatibility with water and (b) an auric ion-containing aqueous solution to precipitate the gold fine particles 3 on the surface of the silver fine particles 2. COPYRIGHT: (C)2006,JPO&NCIPI