Compacted agglomerates of polymer latex particles

Abstract

The present invention provides polymer latex grains having latex particles which compose each coagulated grain compacted therein in the state of not being mutually fused; said grains are obtained by the following steps of (A)-(E): (A) into a polymer latex manufactured by emulsion polymerization or suspension polymerization, a coagulant is added at a temperature lower than the temperature (softening temperature) at which latex particles are adhered by fusion, to be dispersed and scattered in said polymer latex as minute volumes of said coagulant, before said coagulant has been dissolved and diffused into said polymer latex; (B) by letting said coagulant dissolve and diffuse into said latex from the scattered minute volumes of said coagulant, the latex particles are coagulated on the outer surfaces of the minute volumes of said coagulant as the centers, to have coagulated grains grow from inside out, thereby forming spherical grains of an arbitrary range of sizes regularly filled with the latex particles; (C) said coagulated grains are separated from said polymer latex; (D) then, said coagulated grains are immersed in water in the state of holding their temperature lower than the softening temperature of the latex particles; and (E) they are dried at a temperature lower than the softening temperature of the latex particles. The polymer latex grains of this invention have small contents of foreign matters and residual monomers and permit their interior to be homogeneously impregnated with liquid substances; the dried grains may be homogeneously and rapidly dispersed or dissolved in liquid; and further, they are excellent in physical properties like shape holding property, bulk sp. gr., etc.

Dependencies are inferred from the claim text.