Granted Patent B2

US 12,624,227 · App. 17/795,878 · Granted May 12, 2026

Inventors: Hiroyuki Izumi (Tokyo, JP); Kei Togasaki (Tokyo, JP); Hiroshi Yokota (Tokyo, JP)

C09D5/18C09D7/62C09D101/08F16L59/02B05D1/02B05D1/28B05D3/007

Abstract

Claims (20)

1 . A method for manufacturing a thermal insulating material, the method comprising:

applying a coating liquid onto a substrate under a pressure of 1.5 MPa or less with a coater configured to exert the pressure on the coating liquid, to obtain a coated film,

wherein the coating liquid is obtained by mixing aerogel particles, a water-soluble polymer having a hydrophobic group, and a liquid medium under conditions that cause aggregation of the aerogel particles and that result in the coating liquid having, when a diluted solution of the coating liquid is subjected to observation with an optical microscope, an area occupied by the aggregates having a diameter of 20 μm or more relative to an area occupied by the aerogel particles and the aggregates of the aerogel particles within an observation visual field of 50% or more; and

removing at least a part of the liquid medium from the coated film to obtain the thermal insulating material.

2 . The method according to claim 1 ,

wherein the coating liquid comprises aggregates of the aerogel particles, and

an average diameter of the aggregates is 2 to 40 times an average diameter of the aerogel particles.

3 . The method according to claim 1 , wherein a total content of the aerogel particles and aggregates of the aerogel particles in the coating liquid is 70 volume % or more on the basis of a total volume of solid contents.

4 . The method according to claim 1 , wherein the water-soluble polymer comprises a cellulosic resin.

5 . The method according to claim 1 , wherein a pore volume of the thermal insulating material is 0.15 cm 3 /g or more.

6 . The method according to claim 1 , wherein the water-soluble polymer comprises a cellulosic resin having a long-chain alkyl group having 6 to 26 carbon atoms.

7 . The method according to claim 1 , further comprising:

mixing the aerogel particles, the water-soluble polymer, and the liquid medium at a stirring rate to form aggregates of the aerogel particles, wherein the stirring rate limits an average diameter of the aggregates to be 2 to 40 times an average diameter of the aerogel particles; and

prior to applying the coating liquid onto the substrate, forming the coating liquid having the area occupied by the aggregates having the diameter of 20 μm or more relative to the area occupied by the aerogel particles and the aggregates of the aerogel particles within the observation visual field of 50% or more.

8 . The method according to claim 7 , wherein the stirring rate is adjusted in accordance with a viscosity of the coating liquid to limit the average diameter of the aggregates.

9 . The method according to claim 7 , wherein an additive is mixed with the aerogel particles, the water-soluble polymer, and the liquid medium to further limit the average diameter of the aggregates.

10 . The method according to claim 9 , wherein the additive comprises at least one selected from the group consisting of a conditioner, a surfactant, a dispersant and an emulsion resin.

11 . The method according to claim 9 , wherein the additive comprises one or both of a surface conditioner and a surfactant that decreases a surface energy between the aerogel particles and a solution comprising the water-soluble polymer and the liquid medium.

12 . The method according to claim 9 , wherein the additive comprises a dispersant that attaches to a surface of the aerogel particles and forms an electrostatic repulsive force or a steric barrier repulsive force that prevents the aerogel particles from approaching each other.

13 . The method according to claim 12 , wherein the additive comprises an emulsion resin that is dispersed in the liquid medium by the dispersant and is adsorbed on the surface of the aerogel particles.

Assignments (3)

Priority Claims (1)

Continuity (1)

References Cited (45)