Patent ID: 11577490

Abstract:
A heat insulating material includes an aerogel that has macro-pores and meso-pores. A method for manufacturing a heat insulating material, including: a sol preparation step of adding a gelling agent into sodium silicate such that a molar ratio of the gelling agent relative to NaO2 is 0.1 to 0.75, and adjusting a sol into which macro-pores are introduced by leaving unreacted Na and non-cross-linked oxygen in a siloxane skeleton; an impregnating and gelling step of impregnating a nonwoven fabric fiber structure with the sol to form a composite of hydrogel-nonwoven fabric fiber; a hydrophobizating step of mixing the formed composite of hydrogel-nonwoven fabric fiber with a silylating agent to modify a surface thereof; and a drying step of removing a liquid contained in the surface modified composite of hydrogel-nonwoven fabric fiber by drying under a temperature and pressure lower than respective critical values.