Vacuum heat insulator, heat insulation device provided with same, and method for manufacturing vacuum heat insulator

A method for manufacturing a vacuum heat insulator, the method comprising:

• manufacturing an inner box that includes a second opening portion, a second through hole, and a boss provided at a circumferential edge of the second through hole;
• processing a gas barrier sheet made of thermoplastic resin into a first member that includes a first opening portion, and a first through hole formed at a portion facing the second through hole of the inner box, and is box-shaped and so shaped that an outer face of the first member fits with an inner face of the inner box;
• disposing a core material inside the first member, disposing a second member in the first opening portion, and welding the second member to manufacture a gas barrier container;
• and
• disposing the gas barrier container inside the inner box, performing vacuuming, from the first through hole via the second through hole, the inner space defined by the first member and the second member until a degree of vacuum of the inner space defined by the first member and the second member reaches a predetermined degree of vacuum set beforehand, closing the second through hole by thermally welding the boss, fixing a sealing member to a portion of the second through hole of the inner box, and closing the second opening portion by an external plate.