抄録
In recent years the production of PET-film laminated steel sheets for can materials have been rapidly growing to replace lacquered cans because of an environmental concern. To use the film laminated steel cans for beverage and food usage, wet adhesion of the film is one of the most important properties because the film delamination should be suppressed during retort treatments. In this paper, the delamination mechanisms have been studied by investigating the steel surfaces after the films are peeled off in the retort atmosphere, and two factors have been found to suppress the delamination. Firstly, the cohesion failure of the PET film should be suppressed by reducing the thickness of an amorphous PET layer, which is formed on the steel substrate during heat lamination processes. Secondly, the interfacial failure between the film and steel substrate should be suppressed by using adhesion-enhanced steel with appropriate surface finishing such as sufficient amount of electrolytic chromium coating.
