PHOTOCATALYTIC HYDROPHILIC MEMBER, ITS PRODUCTION AND PHOTOCATALYTIC HYDROPHILIC COATING COMPOSITION

摘要

PROBLEM TO BE SOLVED: To obtain a photocatalytic hydrophilic member capable of maintaining high hydrophilic property of the surface over a long period of time by forming a surface layer contg. photocatalytic titanium dioxide and a specified compd. on the surface of a substrate and allowing the surface layer to assume hydrophilic property under a prescribed condition. SOLUTION: This photocatalytic hydrophilic member has a surface layer contg. photocatalytic titanium dioxide and tungsten oxide on the surface of the substrate. The surface layer assumes hydrophilic property represented by <=10 deg., preferably <=5 deg. contact angle to water in accordance with light excitation of the titanium dioxide. This member is produced by coating the surface of a substrate such as a glazed tile with a soln. contg. crystalline titanium dioxide particles such as an ammonia deflocculated anatase type titanium dioxide sol and tungstic acid and carrying out solidification by firing preferably at 500-800 deg.C. It can maintain hydrophilic property over a long period of time even at the time of shielding light.