| 摘要 |
PURPOSE:To improve the heat shrinkability and the heat-shrinkable stress at a low temperature by stretching an unstretched film or sheet made of a copolymer comprising a specified amount of specified copolymerized polyarylate resin and linear polyester. CONSTITUTION:5-45pts. of a copolymerized polyarylate resin comprising terephthalic acid and isophthalic acid (9:1-1:9 in the mol ratio between the terephthalate group and isophthalate group) and a bivalent phenol compound and 95-55pts. of a linear polyester resin are arranged to prepare a copolymerized compound. An unstretched film or sheet made of this copolymerized compound is drawn more than 2.0 times at least in one direction to obtain a heat-shrinkable film. On the drawing operation as mentioned above, uniaxial drawing and sequential biaxial drawing method or the like, that is drawing at the right angle by the tenter method, in addition to the uniaxial drawing can be adopted. |
