| 摘要 |
PURPOSE:To make packaging finish having high-cushioning properties favorable by making a printing aptitude and fitting aptitude of film to a label fitting machine good, by specifying foam density of an intermediate layer, a thickness of an inner and outer surface layers, the total thickness of the film, the modulus of transvrse elasticity and a dimensional shrinkage factor after immersion into a glycerin solution. CONSTITUTION:The subject film is made a three-layer constitution having non-foaming layers and a foaming layer respectively on both sides and the middle and foaming density of an intermediate layer and the total thickness of a foamed film are made respectively a range of 0.35-0.55 and 100-250mum. Then it is suitable that a thickness of an inner surface layer of the foamed sheet and that of an outer surface layer are in a sphere of 5-20mum and 2-3 times as thick as that of the inner surface layer of the side coming into contact with a bottle. When the modulus of transverse elasticity of the film falls within a sphere of 2,500-3,500kg/cm<2>, the same is cut off with a cutter 3, transferred backward with a backward transferring device 4 and a series of processes to fit a label up to a fixed position of the bottle in practicable without hindrance. In the case of shrink packaging, it is necessary that a lateral and longitudinal shrink age factors after immersion into glycerin solution of 120 deg.C for 20 seconds are respective ly at least 50% and not exceeding 5%. |
