| 摘要 |
<p>PROBLEM TO BE SOLVED: To light weight, reduce cost, improve performance, and recycle urethane foam by using powder granulated by highmolecular coagulant organic powder, in a vacuum heat insulator filled core material formed of at least organic powder and inorganic powder in an outer covered material. SOLUTION: A vacuum heat insulator 1 used as the heat insulating material such as a refrigerator is manufactured in such a way that pressure is reduced and exhaust is carried out so as to suppress pressure of an inner part to about 0.1mmHg after a core material formed by mixing urethane powder granulated by highmolecular coagulant and wet silica powder with each other is filled in an outer covered material. In this case, ethyl cellulose is used as the highmolecular coagulant, the adding rate of the ethyl cellulose is set to be within 1weight% or more to 30weight% and less. Granulation is carried out by the highmolecular coagulant, and thereby, the particle diameter of organic powder is regulated optionally. It is thus possible to reduce a solid heat conductivity by contact of excessive small diameter particle, and it is also possible to reduce a heat conductivity.</p> |
