| 摘要 |
PURPOSE:To obtain the title film improved in mechanical properties, traveling performances, abrasion resistance and flatness by forming polyethylene 2,6- naphthalate containing specified vaterite CaCO3 particles into a film and bi- axially orienting the film. CONSTITUTION:Polyethylene 2,6-naphthalate containing 0.005-2.0wt.% vaterite CaCO3 particles having a mean particle diameter of 0.07-1.5mum and a particle diameter distribution defined by the formula [wherein d25 and d75 are diameters (mum) at 25% and 75% cumulative volumes when the particles are weighed from the side of the larger particle] of 1.60 or below is extruded at 280-320 deg.C into a sheet, and this sheet is rapidly cooled to obtain an amorphous sheet. This sheet is oriented biaxially at a draw ratio of 3.5 or above and heat-treated for 0.1-10sec at 180-260 deg.C obtain a biaxially oriented polyethylene 2,6-naphthalate film having a sum of F-5 values in the machine and crosswise directions of 25kg/mm<2> or above, and a resistivity in a molten state of 1X10<7>-5X10<8>OMEGA-cm. |
