Manufacturing method for a vaccum heat insulator
A vacuum heat insulator small in limitation in shape of applicable objects, and wide in application is presented. A vacuum heat insulator is formed of a plurality of core members of thickness of 5 mm or less made of glass fiber shaped nearly in a regular octagonal shape, being coated with a gas barrier enveloping member and evacuated in side. The core members are shaped in octagon, and disposed in lattice layout at specified intervals so as to form folding lines in four directions of vertical, lateral and oblique 45-degree directions, parallel to each side. In order that the plurality of core members may be located in independent spaces individually, the entire surface of the enveloping member around the core members is formed as heat seal parts, and it is foldable in four directions and is flexible. By cutting the heat seal parts along the core members so as to leave about 3 mm in the periphery, a vacuum heat insulator of any desired shape and wide effective heat insulating area can be obtained. The core members may be formed in desired shape, and complicated shapes and through-holes can be formed, so that vacuum heat insulators applicable in a very wide scope of purposes can be presented.
1. A method of manufacturing a vacuum heat insulator comprising the steps of:
heat fusing heat seal layers of first and second enveloping members, the first and second enveloping members comprising laminate films, and each of the laminate films comprising the heat seal layer and a surface protective layer, wherein heat is applied to every portion of the first and second enveloping members including portions of the first and second enveloping members in which a flat core member is present between the first and second enveloping members; and
heat pressing every portion of the first and second enveloping members, including the portions in which the flat core member is present between the first and second enveloping members, by applying a force of 1 kg/cm 2 or more at the same time as the fusing step,
wherein the heat pressing is performed at a fusing temperature of the heat seal layers,
wherein the vacuum heat insulator comprises the first and second enveloping members and the flat core member and each of the first and second enveloping members comprises the heat seal layers,
wherein the flat core member is sealed under reduced pressure between the first and second enveloping members, and the heat seal layers of the first and second enveloping members face each other, and
wherein the first and second enveloping members are heat sealed at every portion of the first and second enveloping members that are in contact with each other.
2. The method of claim 1 , wherein the first and second enveloping members are heated and pressed by a hot plate.
3. The method of claim 2 , wherein the hot plate is made of an elastic material.
4. A method of manufacturing a vacuum heat insulator comprising the steps of:
heat fusing heat seal layers of first and second enveloping members, the first and second enveloping members comprising laminate films, and each of the laminate films comprising the heat seal layer and a surface protective layer, wherein heat is applied to every portion of the first and second enveloping members including portions of the first and second enveloping members in which a flat core member is present between the first and second enveloping members, and peripheral portions of the flat core member where the flat core member is not present between the first and second enveloping members; and
heat pressing every portion of the first and second enveloping members, including the portions in which the flat core member is present between the first and second enveloping members and the peripheral portions of the flat core member where the core member is not present between the first and second enveloping members, by applying a force of 1 kg/cm 2 or more at the same time as the fusing step,
wherein the heat pressing is performed at a fusing temperature of the heat seal layers,
wherein the vacuum heat insulator comprises the first and second enveloping members and the flat core member and each of the first and second enveloping members comprise the heat seal layers,
wherein the flat core member is sealed under reduced pressure between the first and second enveloping members, and the heat seal layers of the first and second enveloping members face each other,
wherein a heat-sealed portion is formed at a periphery of the flat core member by heat-sealing the heat seal layers of the first and second enveloping members with each other, and
wherein no non-heat-sealed portion is present between the core member and the heat sealed portion at the periphery of the core member.
5. The method of claim 4 , wherein the first and second enveloping members are heated and pressed by a hot plate.