To obtain an antifogging agent good in the endurance of antifogging property, and used for a glass, a mirror, a metal, etc., by using an organopolysiloxane having an anionic group such as a phosphoric ester group, a sulfuric ester group, a sulfonic acid group, etc., in one molecule and a specific molecular weight.
This antifogging agent extremely easily used for a general household and for a business use, having an excellent antifogging property and an endurance of several days in a bath room, consists of an organopolysiloxane having at least one anionic group of at least one kind such as a phosphoric acid ester (salt) group, a sulfuric ester (salt) group, a sulfonic acid (salt) group, a sulfosuccinic acid ester (salt) group, a carboxylic acid (salt) group, etc., in one molecule and 500-30,000 weight averaged molecular weight, which is obtained by reacting an organopolysiloxane modified by a polyoxyalkylene at the both of the ends by adding phosphoric acid anhydride, chlorosulfonic acid, sulfosuccinic acid monosodium salt, or acrylic acid thereto followed by heating in a solvent such as xylene.
ITO RYUICHI
TSUNEKAWA TOSHIO
