Thermal insulation sheet and manufacturing method therefor
A thermal insulation sheet is used that includes a fiber, a silica aerogel contained in the fiber, and a fibrous cavity. A method for manufacturing a thermal insulation sheet is used that includes: an impregnation step of impregnating a silica aerosol in a nonwoven fabric substrate containing a fiber that is insoluble in an acidic solution, and a fiber that is soluble in the acidic solution; a gelling step of gelling the silica aerosol; a hydrophobizing step of hydrophobizing the gel; and a drying step of drying the gel. The fiber that is soluble in the acidic solution is dissolved in the hydrophobizing step.
1. A method for manufacturing a thermal insulation sheet, the method comprising:
an impregnation step of impregnating a silica aerosol solution in a nonwoven fabric substrate containing a first fiber that is insoluble in an acidic solution, and a second fiber that is soluble in the acidic solution;
a gelling step of gelling the silica aerosol solution;
a hydrophobizing step of hydrophobizing the gel; and
a drying step of drying the gel,
the second fiber being dissolved in the hydrophobizing step.
2. The method according to claim 1 , wherein the second fiber is at least one of nylon, rayon, cupra, acetate, vinylon, and cotton.
3. The method according to claim 1 , wherein the second fiber has a diameter or 0.2 mm or less, and a length that is at least twice as long as the diameter.
4. The method according to claim 1 , wherein the second fiber has a diameter of 0.01 mm or more.