Formation manner null of permeable water absorption prevention material content constituent and permeable water absorption prevention

摘要

PROBLEM TO BE SOLVED: To provide a composition which prevents cissing on a recoated section and is excellent in finished appearance by incorporating an acrylic synthetic resin emulsion, a silane-base permeable and water absorption-preventing material and an organic solvent having specified solubility parameter and water solubilty, each in a specified amount, into the same. ;SOLUTION: This composition comprises (A) 100 pts.wt. (in terms of solid) acrylic synthetic resin emulsion having an average particle size of 80-300 nm, (B) 30-400 pts.wt. (in terms of solid) silane-base permeable and water absorption- preventing material and (C) 5-50 pts.wt. organic solvent (e.g. ethylene glycol monomethyl ether) having a solubility parameter of 8.5 or higher and a water solubility of 20 wt.% or higher. Ingredient A is prepared by copolymerizing an alkyl-containing (meth)acrylic monomer, a hydroxyl-containing (meth)acrylic monomer, etc. Ingredient B is prepared by converting a hydrolyzable silane compound (e.g. methyltrimethoxysilane) into an aqueous emulsion by using a surfactant (e.g. a nonionic or anionic one).;COPYRIGHT: (C)2000,JPO