AQUEOUS POLYMERIC DISPERSIONS AND PAPER COATING COMPOSITIONS

摘要

Lightweight coated paper articles having a desirable combination of properties are obtained through the use of coating compositions employing as the binder component thereof certain novel polymeric dispersions which comprise a major proportion on a dry basis of an alkali insoluble polymer and a minor proportion (e.g., from about 0.5 to about 25 weight percent on a dry basis based upon the alkali insoluble polymer) of certain alkali soluble polymers. Exemplary of the alkali insoluble polymers employed herein are both the carboxylated and noncarboxylated versions of known addition polymerized synthetic polymers having a glass transition temperature of about 50 DEG C. or less. Exemplary of the alkali soluble polymers employed herein are synthetic addition polymers comprising (in polymerized form and in weight percent based on such polymer) from about 40 to about 90 percent of a vinyl ester of a carboxylic acid (e.g., vinyl acetate, vinyl propionate, etc.); from about 5 to about 55 percent of the nitrile or a C1-C8 alkyl ester of a monoethylenically unsaturated carboxylic acid; and from about 5 to about 15 percent of a monoethylenically unsaturated carboxylic acid.