抄録
Polyester film laminated steel for can container will gradually replace lacquer coated steel sheet from environmental concern and cost consideration. The process of lamination is characterized by partial melting of the film on the surface of steel during lamination by pressing the supplied films between both sides of heated steel and a couple of cooled rubber rolls. Various characteristics of film laminated steel for can use are strongly influenced by the degree of biaxial orientation and the thickness of amorphous layer of the laminated film, and the characteristics are greatly influenced by several laminating conditions.
Therefore, this report deals with the result of numerical analysis applied to characterize heat transfer in laminating process, in order to estimate the variation of orientation of the laminated film. From the result of numerical analysis, we found that the cross-sectional temperature distribution in roll nip greatly changes within extremely short time, and the distribution contributes to the formation of double layered structure of amorphous and biaxially oriented layers.
Moreover, it was found important to form the double layered structure of the laminated film by keeping an appropriate temperature profile of film in roll nip. The thickness of amorphous layer with the numerical analysis obtained by the cross-sectional variation of maximum temperature of film in the roll nip agrees well with the one observed by polarizing microscope. The estimation of the thickness of amorphous layer was found possible by this method with a good accuracy.
