VACUUM HEAT INSULATING MATERIAL AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a vacuum heat insulating material and its manufacturing method: suitable for use at a high temperature; having a sufficient pressure resistance; light in the weight; reducing the powderiness on the surfaces; maintaining a softness which fibers have; maintaining the heat insulating performance for a long period of time; and manufacturable comparatively easily. SOLUTION: The vacuum heat insulating material is formed by filling a vessel with an insulating member consisting of fibers and sealing the vessel in the evacuated condition, wherein a strong fixation part is formed by binding the intersections of fibers fast to a part of the insulating member chiefly using an inorganic binder so that the vessel walls are supported from the inside and prevented from recessing by a pressure difference between inside and outside when the vessel is evacuated, while the remaining part of the insulating member is made a soft part free of binding or relatively less so that the insulating member is prevented from cracking with a compressive stress applied from the vessel walls at the time of evacuation.