Inorganic foam and preparation thereof

摘要

A highly expanded inorganic foam containing discrete cells with an average diameter of 3 mm or less, being non-flammable with excellent thermal insulating property, heat resistant property as well as water resistance is found to be prepared by foaming and setting simultaneously at normal temperature by adding a suitable amount of a polyvalent metal carbonate to a stable aqueous solution dispersion of a metal phosphate with a specific atomic ratio of metal to phosphorus and a specific ratio of metal valences relative to phosphate ion valences.