METHOD OF MANUFACTURING HYDROPHOBIC DRY-GEL AND HEAT INSULATING MATERIAL USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing a hydrophobic dry-gel without using a solvent displacement process which is needed when a treatment for obtaining a hydrophobicity is applied by using a silylling agent, etc., and a solvent which does not react with the sililling agent when drying a silica wet-gel having water without shrinkage. SOLUTION: A low density dry-gel can be efficiently obtained by applying the treatment for obtaining the hydrophobicity to a wet-gel having water in a solution obtained by mixing a water soluble solvent, a water insoluble solvent and a sililling agent, and by omitting or simplifying the solvent displacement process, and further by drying the hydrophobic gel at a condition under the critical point.