MULTILAYER STRUCTURE AND MANUFACTURE THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a laminated polymer film structure having substantially no warpage (bent, twist and warp) SOLUTION: The individual layers of polymer films laminated so as to form a card structure are selected so that the mechanical properties (thickness, tensile strength, elongation percentage, shrinkage factor and machining direction of the layer) of one or a pair of layers are canceled by those of the other layer. In the three-layer board of one embodiment, the tensile strength, elongation percentage and shrinkage factor of the outer film layer of the board are the same, and the outer layer has larger tensile strength than that of the inner layer. To obtain the aligned layer, the orientation, machining direction of processing of the film and the orientation of the coil set of the film are considered.