Aqueous polymeric latex

Abstract

The present invention relates to aqueous polymer latex of film-forming copolymer particles, obtainable by aqueous emulsion polymerization of monoethylenically unsaturated monomers M, comprising mainly non-ionic monomers of the group consisting of alkyl acrylates (methacrylates), cycloalkyl acrylates (methacrylates) and monovinyl aromatic hydrocarbon monomers, and further comprising 0.01 to 1% by weight, based on the total weight of the M monomers, of at least one monoethylenically unsaturated monomer M2 having a hydrolyzable silane group; and from 0.1 to 2% by weight, based on the total weight of the monomers M, of at least one monoethylenically unsaturated monomer M3 having an acidic phosphate group, or a salt thereof, and wherein the copolymer particles in the polymer latex have a volumetric median particle diameter of at least 250 nm,as determined by dynamic light scattering according to ISO 13321:1996. Polymeric latexes are particularly suitable as binders in coating compositions with a high pigment volume concentration (PVC), preferably greater than 60%, and provide good wet scrub resistance and opacity to the coatings obtained from them. The present invention also relates to a process for producing said polymeric latexes, to aqueous coating compositions containing these latexes, and to the use of said polymeric latexes to improve the wet scrub resistance and opacity of coating compositions with a pigment volume concentration (PVC) preferably greater than 60%.