摘要 |
PURPOSE:To obtain a strong humidity exchange element with much adhesion of silica aerogel, by impregnating paper, which is obtained by laminating and molding inorg. fibers according to a papermaking process, with water glass and, after drying under heating, infiltrating an acid into the impregnated paper to form a silica hydrogel before washing and drying. CONSTITUTION:Flat papers and corrugated papers, both of which are formed of low density paper prepared from inorg. fibers such as ceramic fibers by a papermaking process, are alternately laminated to be molded into a honeycomb shape. A process such that this molded body is impregnated with an aqueous water glass solution and the impregnated one is dried, is repeated to form a honeycomb body containing papers as a skeletal and comprising hydrated water glass layers with water content of 3-20% and this honeycomb body is immersed in an aqueous sulfuric acid solution while shaking to form a silica hydrogel from water glass. The treated honeycomb body is washed with water and dried under heating to obtain a humidity exchange element comprising the inorg. fibers as a skeletal and based on a silica aerogel, is obtained. |