Patent ID: 6036814
Filing Date: 2000-03-14
Classification: B21D,B32B,F28F,Y10T

Abstract:
A method of heating a metal sheet by means of a thermal transfer roll having a prescribed heat transfer pattern comprising a high temperature portion and a low temperature portion formed on the surface of said thermal transfer roll by varying heat resistance inside said thermal transfer roll, wherein said low temperature portion comprises an indented portion formed on said thermal transfer roll, and a lid member for closing said indented portion, said method comprisingheating said thermal transfer roll to the temperature range where said high temperature portion has a temperature which enables a lowering of the degree of crystal orientation of a resin film having crystal orientation, andbringing said thermal transfer roll into contact with a metal sheet so as to heat portions of the metal sheet which come into contact with said high temperature portions of said thermal transfer roll up to a temperature in which the degree of crystal orientation of the resin film can be lowered, and portions of the metal sheet which come into contact with said lower temperature portion of said thermal transfer roll are heated up to a temperature which is higher than a temperature necessary for adhering the resin film and lower than a temperature necessary for lowering the degree of the crystal orientation of the resin film.