There are two types of barrier films used to resist the permeation of gases and water vapor into VIPs. One is metal
foils(AF) consisting of a central aluminium barrier layer, laminated between an outer PET layer for scratch
resistance and an inner PE sealing layer, and the other is metallized films(MF) made from up to three layers of
aluminium coated PET films and an inner PE sealing layer[14,15]. The anti-permeation performance of barrier films
has been investigated deeply and comprehensively in Germany and Switzerland. The rate of pressure rise and mass