摘要 |
PURPOSE:To obtain the title film which damages the edge of a cutting machine little, excels in particle dispersion, hiding power, etc. and is suitable for the production of labels, etc., by specifying the Mohs' hardness and amount of white inorganic particles added, the content of voids formed by stretching, etc. CONSTITUTION:A polyethylene terephthalate containing 5-30wt.% white inorganic particles of a Mohs' hardness <5 (e.g., titanium oxide or calcium carbonate) is produced by adding white inorganic particles to the reaction system during the production of the polyethylene terephthalate. This polyethylene terephthalate is fed to an extruder and molded into a film. The obtained unstretched sheet is biaxially stretched to a void content of 5-30% to obtain the purpose white polyethylene terephthalate film. In this way, the damage of the cutting edge can be reduced because the Mohs' hardness of the white inorganic particles and the content of voids which function as a buffer during cutting are specified. |