| 摘要 |
PURPOSE:To obtain a film improved in the drawing property and excellent in transparency, apperance and slidability by applying uniaxial drawing to an undrawn sheet of polyester compounded with a specified quantity of specific pulverized silica. CONSTITUTION:The polyester whose main unit is ethylene terephthalate is compounded with the pulverized silica in the particle diameter of 0.01-10mu or preferably 0.1-5mu which is coated with polyolefin wax and accounts for 0.01-3wt% or preferably 0.025-0.5wt% in the entire composition, and the polyester composition thus formed is melted and extruded. Then the extruded sheet is drawn uniaxially in the longitudinal direction twice or more, or preferably 2.5 times or more under the temperature of 80-140 deg.C by using a roll drawing machine. In addition, as occasion calls, the 2nd-axial drawing is conducted in the direction of width. |
