| 摘要 |
Single- or multi-layered, biaxially oriented and heat-set film based on polyester, comprises a layer or at least one layer based on polyester comprising 0.25-1.5 wt.% of spherical particles of organic and/or inorganic/organic material, based on the total weight of the layer. The particles are insoluble in polyester. The particles exhibit an average particle size of 0.5-3 mu m and comprises titanium dioxide (0.25-1.5 wt.%) particles with an average particle size of 0.02 0.6 mu m. An independent claim is also included for producing the film, comprising (a) extruding a polyester melt, which comprises the spherical particles and the titanium dioxide particles with a wide slot nozzle, (b) removing and solidifying the resulting precursor film on at least one, preferably cooled roller, (c) biaxially orienting the solidified precursor film preferably first in a longitudinal direction at 80-130[deg] C, then in a transverse direction at 80-150[deg] C, (d) heat-setting the oriented film over a period of 0.1-10 seconds at a temperature of 150-250[deg] C, and (e) optionally coating the heat-set film, where the coating exhibits preferably adhesion-promoting, anti-static, slippage enhancing, hydrophilic and/or anti-adhesive properties. |
