Surface treatment agent of building materials

摘要

PURPOSE:To obtain a surface treating agent rendering superior water repellency, oil repellency and stainproofing property to the surfaces of building materials when applied to or impregnated into the surfaces by using organopolysiloxane having specified groups bonding to silicon atoms in the molecule as a base. CONSTITUTION:This surface treating agent is based on organopolysiloxane having at least one group bonding to Si represented by formula I in one molecule. In the formula I, R is a monovalent hydrocarbon group, R1 is a divalent hydrocarbon group, X is a hydrolyzable group, preferably alkoxy and (a) is 0, 1 or 2. The organopolysiloxane used is preferably represented by formula II or H. In the formulae II, III, R is a monovalent hydrocarbon group and plural R's may be different from each other and are preferably methyl or a combination of methyl with =4C alkyl.