Foamed inorganic pore-forming or insulating material

摘要

A light building stone, especially a porous brick, with pores produced by a foamed organic pore-forming agent, contains or separates practically no benzene and benzene derivatives and has pores which contain small quantities of sintered kieselguhr as firing residue of an expanded starch-kieselguhr pore-forming agent. Also claimed is a pore-forming agent and insulating material, especially for use in production of the above light building stone, the material consisting of a mixture of 70-90 wt.% starch and 30-10 wt.% dried kieselguhr which is foamed to a bulk density of 10-80 (preferably 35-40) kg/m<3> and which has a particle size of 0.5-15 (especially 1-5) mm. Further claimed is a process for production of the above pore-forming agent and insulating material by expansion of organic material.