MANUFACTURE OF METALLIC VACUUM HEAT-INSULATING DOUBLE VACUUM BOTTLE

摘要

PURPOSE:To prevent degradation of heat insulation of a vacuum bottle by a method wherein a titanium getter is arranged in the vicinity of a mouth either of a metal outer cylinder or a metal inner cylinder so that attachment of plated metal to an outer surface of the mouth of the metal inner cylinder and an inner surface of the mouth of the metal outer cylinder can be prevented completely. CONSTITUTION:A titanium getter 7 is arranged at a mouth. By this, the titanium getter 7 which has affinity for oxygen and nitrogen responds to gaseous oxygen and gaseous nitrogen to make oxides under vacuum heating, and these oxides are attached to an outer surface of a mouth of a metal inner cylinder 3 and an inner surface of a mouth of a metal outer cylinder 2, both surfaces being not plated with metal. This titanium oxide works as a so-called protecting film to prevent plated metal from attaching to the outer surface of the mouth of the metal inner cylinder 3 and the inner surface of the mouth of the metal outer cylinder 2. In addition, as the titanium oxide is not attached to a part except the mouth of the metal outer cylinder 2, atoms of the plated metal attached to the metal inner cylinder 3 are attached to the part by vacuum deposition. Accordingly, a vacuum bottle prominent in the heat insulation can be obtained.