Vacuum heat insulating material, method of producing vacuum heat insulating material, and heat insulating box body using vacuum heat insulating material

A method of producing a vacuum heat insulating material, the method comprising:

• covering a core member with envelope members in a reduced pressure space, each of the envelope members having a gas barrier layer and a heat-seal layer,
• maintaining the reduced pressure space at a temperature higher than a melting point of the heat-seal layers so as to bring the heat-seal layers to a molten state;
• increasing the pressure, while pressing the peripheries of the envelope members so that the envelope members are in contact with each other;
• and
• heat-sealing the envelope members including a non-pressed portion of the envelope members.

A method of producing a vacuum heat insulating material, the method comprising:

• sealing envelope members in a reduced pressure space with a core member placed inside the envelope members, each of the envelope members being a laminated film having a gas barrier property and a heat-seal layer inside thereof;
• and
• applying sufficient heat, out of contact to the envelope members, to melt the heat-seal layer, and
• heat sealing where the envelope members are in contact with each other, after making an outer pressure of the sealed enveloping members to be an atmospheric pressure so as to make portions of the envelope members contact with each other by a difference of pressure between an inner pressure and the outer pressure of the sealed enveloping members, the portions being portions where no core member is placed between the envelope members.

A method of producing a vacuum heat insulating material, the method comprising:

• covering a core member with envelope members, each of the envelope members having a gas barrier layer and a heat-seal layer,
• evacuating an inside of the envelope members and heat sealing peripheries of the envelope members;
• and
• uniformly applying heat sufficient to melt the heat-seal layer, and
• heat sealing where the envelope members are in contact with each other, inside the heat-sealed peripheries.

A method of producing a vacuum heat insulating material, the method comprising:

• heat-sealing a non-sealed portion of a vacuum heat insulating material by applying a sufficient heat out of contact to the non-sealed portion, to melt a heat seal layer of an envelope member comprising the vacuum heat insulating material, wherein
• the vacuum heat insulating material comprises:
• a core member covered with the envelope members, the envelope member being a gas barrier laminated film with the heat-seal layer disposed inner side of the envelope member, and the inner side of the envelope members being evacuated;
• a sealed portion where an entire outer periphery of a peripheral fin of envelope members is heat-sealed;
• and
• the non-sealed portion where the envelope members are not heat-sealed and in contact with each other by an atmospheric pressure, the non-sealed portion being an inner periphery of the sealed portion.

A method of producing a vacuum heat insulating material, the method comprising:

• inserting a core member into a bag-shape envelope member, the envelope member being formed by sealing three sides of laminate films having gas barrier property and including heat-seal layers;
• forming the vacuum heat insulating material by pressing an opening of the envelope member by a heater in a reduced pressure space, followed by taking the vacuum heat insulating material out of the reduced pressure space, the vacuum heat insulating material having a sealed portion where an entire outer periphery of a peripheral fin of the envelope member is heat-sealed;
• and
• heat-sealing a non-sealed portion of the vacuum heat insulating material by applying a sufficient heat out of contact to the non-sealed portion, to melt a heat seal layer of an envelope member comprising the vacuum heat insulating material, the non-sealed portion being an inner periphery of the sealed portion of the peripheral fin of the envelope member, and the laminated films comprising the envelope member being in contact with each other by an atmospheric pressure.