THERMOEXPANSIBLE MICROSPHERE, PROCESS FOR PRODUCING THE SAME AND METHOD OF USE THEREOF

摘要

A thermoexpansible microsphere comprising an outer shell of thermoplastic resin and, incorporated therein as a blowing agent, a fluorocompound of C2-C10 ether structure not containing chlorine and bromine which is gasified at temperatures not higher than the softening point of the thermoplastic resin; a process for producing the same; and a method of use of the thermoexpansible microsphere. The thermoexpansible microsphere exhibits a variation coefficient (Cv) of particle size distribution of 30% or below when the average particle diameter falls within the range of, for example, 1 to 100 mum. This thermoexpansible microsphere reduces environmental burden, excels in flame retardancy and incombustibility and is extremely sharp in particle size distribution. This thermoexpansible microsphere and thermoexpanded microsphere therefrom are suitable for not only conventional uses but also use in fire-resistant paints, flame retardant or nonflammable heat insulators, flame retardant or nonflammable lightweight fillers and flame retardant or nonflammable lightweight moldings.