SILICONE FREE DEFOAMER FOR SOLVENT BASED COATINGS

摘要

The invention relates to a silicone free defoamer for solvent based coatings, especially clear wood coatings preferably based on a graft copolymer of poly alkyl vinyl ether. The coating composition is comprising a resin binder component, and a defoamer formulation comprising a) a graft copolymer of the Formula (I) wherein A are polymerizable monomers or comonomers selected from alkyl vinyl ether, phenyl vinyl ether, allyl ether, acrylate, methacrylate, olefin, maleic anhydride or styrene; [A]m represents a homopolymer or copolymer or a mixture thereof containing one or more monomers A and being the graft backbone and being selected from poly alkyl vinyl ether, poly phenyl vinyl ether, poly allyl ether, polyacrylate, poly methacrylate, poly(alkyl vinyl ether-co-acrylate), polyolefin, alkyl vinyl ether-maleic anhydride copolymer or polystyrene; [B]n represents the units in the backbone [A]m+n where a branch is grafted from the unit in the backbone; Y are polymerizable monomers or comonomers selected from (meth) acrylate, styrene, vinyl acetate; [Y]p is a grafting chain which is a homo/copolymer of one or more monomers selected from (meth) acrylate, styrene, vinyl acetate; p = 1 -5000 m is a number between 1 -5000, n is a number of 1 -5000; and m + n is a number of 30-5000. b) polymer, mixed polymers or copolymer [A]m+n; and c) polymer, mixed polymer or copolymer of the monomer(s) Y.