HEAT INSULATING MATERIAL AND ITS MANUFACTURING METHOD

PROBLEM TO BE SOLVED: To provide a heat insulating material which eliminates a flanged lug portion, reduces gas leakage due to the folding of the lug portion, and suppresses heat leakage from an abutting portion. SOLUTION: The vacuum heat insulating material 1 comprises a frame body 4, a core material 3, and a barrier film 2 for covering the frame body 4 at its top and bottom faces, and is formed by inserting the core material 3 into an opening portion 5 of the frame body 4, covering the frame body 4 at its upper and lower faces 4a, 4b with the barrier film 2 and putting it into a vacuum chamber for vacuuming, and giving heat seal to the peripheral edges of the frame body 4 and the barrier film 2 to seal the opening portion 5. A recessed portion 6 and a protruded portion 7 engageable with each other are provided at the peripheral edge of the frame body 4. The construction eliminates the flanged lug portion, reduces gas leakage due to the folding of the lug portion, and suppresses heat leakage from the abutting portion. COPYRIGHT: (C)2008,JPO&INPIT