Abstract: This invention relates to an improvement in the process of preparing porous ceramic articles which are formed by blending a composition containing a polyolefin, a ceramic filler and a plasticizer; shaping the blend; extracting the plasticizer and firing the article to remove the polyolefin. The improvement comprises soaking the extracted article in a water solution of a surfactant prior to firing which results in a substantial reduction in the number of cracked pieces when firing many pieces simultaneously.

Abstract: A fire-retardant, intumescent laminate system suitable for application to combustible or heat-sensitive substrates comprises an intumescent layer which is a porous sheet material, e.g., paper or foams saturated with an intumescent composition and having a flexible protective layer adhered to the intumescent layer. The intumescent laminate system may include a vapor barrier layer, e.g., aluminum foil and/or a thermal barrier layer, e.g., glass wool or cardboard adjacent to the intumescent layer, and is particularly suitable as a protective, fireretardant overlay on thermally delicate substrates such as organic foams, e.g., polystyrene.