Polyurea-covered particle having narrow particle size distribution and its production
AssigneeNippon Paint Co., Ltd.
InventorsNaoya Yabuuchi, Shinichi Ishikura
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Abstract
The present invention provides a polyurea-covered particle having a narrow particle size distribution, which comprises a vinyl polymer particle as a seed particle and a polyurea cover layer formed on the vinyl polymer particle. The present invention also provides a process for producing the polyurea-covered particle having a narrow particle size distribution, which comprises: dispersing vinyl polymer particles having a narrow particle size distribution in an aqueous medium, adding thereto a polyisocyanate compound to swell the vinyl polymer particles, and adding a polyamine compound to effect interfacial polymerization.
Claims7
A process for production of a polyurea-covered particle having a narrow particle size distribution, comprising a vinyl polymer particle as a seed particle and a polyurea cover layer formed on the vinyl polymer particle, which process comprises:
- dispersing vinyl polymer particles having a narrow particle size distribution in an aqueous medium,
- adding thereto a polyisocyanate compound to swell the vinyl polymer particles, and
- adding a polyamine compound to effect interfacial polymerization,
- wherein the resulting polyurea-covered particle has a weight average particle size of 1.0-30.0 .mu.m and a particle size distribution variation coefficient of less than 20%.
Dependencies are inferred from the claim text.