Biaxial orientation polyethylene terephthalate film null for heat sensitive transcription

摘要

PURPOSE:To enhance the uniformity of a thermal transfer layer by using a polyester film, whose specific resistance at a melting time is set to a specific value, obtained using an electrostatic cooling method. CONSTITUTION:The specific resistance of polyethylene terephthalate at the time of melting must be 5X106-5X108OMEGA-cm. A metal component may be made soluble in polyethylene terephthalate in order to reduce specific resistance and, for the sake of this, for example, a means for adding a relatively small amount of a phosphorus compound to a metal element used as an transesterification catalyst or a metal element added during or after reaction is pref. In order to increase specific resistance, the amount of the metal element dissolved in polyethylene terephthalate may be reduced and, concretely, the addition amount of a metal compound soluble in a reaction system may be reduced or the greater part of the metal compound may be precipitated as a metal salt insoluble in polyethylene terephthalate.