FOAMED GLASS AND THERMALLY INSULATING MATERIAL USING THE SAME, AND METHOD FOR PRODUCING FOAMED GLASS

摘要

A foamed glass which has foamed cells having been formed by contacting a glass powder with high temperature and high pressure steam or high temperature and high pressure water to thereby subject the glass fiber to a hydrothermal treatment and then sintering and foaming the resultant glass powder, and having an average pore diameter of 10 to 1000 μm, preferably 15 to 700 μm. The foamed glass is excellent in uniformity, since the water having penetrated into the inside of particles of a glass powder is expanded by heating and each of the particles is foamed, resulting in the uniform dispersion of a number of closed cells. It also has a low bulk density and is excellent in lightweight property and thermal insulation, since many closed cells are dispersed. Further, it can be easily subjected to a machining such as cutting, drilling or the like with a saw, a drill or the like and is excellent in machinability, since the diameter of the above pores is small and the wall between the pores is thin.