EXPANDED HOLLOW MICRO SPHERE COMPOSITE BEADS AND METHOD FOR THEIR PRODUCTION

摘要

The invention provides expanded hollow micro sphere composite beads and a process for producing the beads. According to the invention, finely divided calcium carbonate can be uniformly deposited on expanded hollow thermoplastic polymer micro spheres by a simple procedure without incurring breakage of the expanded micro spheres so that the scattering of beads can be effectively inhibited. The preferred production process comprises admixing expanded hollow thermoplastic polymer micro spheres (A) with colloidal calcium carbonate (B) which has been surface-activated with a surface-treating agent or dispersing agent, e.g. a fatty acid series or polymer acid series compound. The admixing can be typically effected by dry-blending, preferably at a temperature of about 50-100 DEG C.