Fine polyurethane particles, colloidal polyurea particles, and production processes thereof

摘要

Fine polyurethane particles or fine polyurethane gel particles, which have been surface-covered with colloidal polyurea particles, are provided. They are produced by emulsion polymerization of a polyisocyanate compound and an active-hydrogen-containing compound in an inert liquid while using colloidal polyurea particles as an emulsifier.