Process of preparing inorganic light weight foam

Abstract

A foamable composition for preparing inorganic light weight foam includes an inorganic powder and vinyl chloride-based resin as main components, and an organic solvent and a foaming agent. The vinyl chloride-based resin is a higher molecular weight resin made by suspension-polymerization or mass-polymerization, and has an average degree of polymerization (p) of 1300 to 10000 as defined by JIS K-6721-1959. The ratio by weight of the inorganic powder to the vinyl chloride-based resin ranges from 50:50 to 85:15. The organic solvent has a solubility parameter (.delta.) of 7 to 10, and a boiling point of 80.degree. C. to 140.degree. C. The ratio by weight of the organic solvent to the total amount of the inorganic powder and the vinyl chloride-based resin ranges from 60:40 to 40:60. The inorganic powder and vinyl chloride-based resin components are kneaded at between 140 and 200 degrees Celsius, while applying a shearing force on the kneaded composition. The organic solvent and foaming agent are mixed with the kneaded composition at 40 to 80 degrees Celius, thereby forming a foamable composition which is molded and foamed under pressure at between 150 and 180 degrees Celsius.

Dependencies are inferred from the claim text.