Patent ID: 8236401

Claim:
A vacuum insulator comprising: an internal structure; a filler for filling empty spaces of the internal structure; and an envelope having an upper envelope composed of a metal layer and a polymer layer formed on the metal layer to surround an upper surface of the internal structure, and a lower envelope composed of a metal layer and a polymer layer formed on the metal layer to surround a lower surface of the internal structure, wherein the metal layer of the upper envelope and the metal layer of the lower envelope are opposite to each other, wherein in a certain area along outlines of the upper envelope and the lower envelope, the metal layer of the upper envelope and the metal layer of the lower envelope are adhered by polyurethane, and in an area excluding the certain area, the metal layer of the upper envelope and the metal layer of the lower envelope between which a film composed of a Low density polyethylene LDPE and a LinearLow density polyethylene LLDPE is inserted, are adhered by heat.