HOLLOW POLYMER LATEX PARTICLES

摘要

This invention relates to polymer particles that are acid-free in the swellable polymer core and to hollow polymer particles derived therefrom, and to a process for the production of these particles. The acid-free core advantageously decreases the polymer particle's affinity to water. Applicants have discovered that non-carboxylated latexes having a variety of Tg's will swell at temperatures higher than the Tg of the polymer. These latex particles are useful as opacifying plastic pigments for various coatings and particularly as gloss-enhancing plastic pigments for paper and paperboard coatings. Preparation of the hollow polymer particle comprises the use of (meth)acrylate ester monomers, vinyl esters of carboxylic acids or a mixture thereof which are hydrolyzable and swellable at higher temperatures in alkaline environments. The particles may be encapsulated with a hard shell.