| 摘要 |
PURPOSE:To make dimensional stability prominent and prevent the generation of the age wrinkles of a film by a method wherein the outside of a film roll is wrapped by a moisture permeable protect6ion member and the aging process of the roll is effected under an atmosphere having a high humidity. CONSTITUTION:A film roll, made by winding an uniaxially strethced polyethy lene terephthalate film or a biaxially stretched polyethylene terephthalate film by a normal method, is wrapped by a moisture permeable protection member to effect aging. The aging is effected for 5hr-20 days under the temperature from a room temperature to the transitional point of glass or preferably under the temperature of 40-65 deg.C in an atmosphere having a relative humidity 40% or more. The aging temperature of the film, consisting of the homopolymer of polyethylene terephthalate, is 35-70 deg.C generally. It is necessary that the aging process suffices the set value of relative humidity within the range of + or -5% (preferably + or -2%). |
