摘要:
A method for producing a polyester resin film includes melt extruding a polyester resin into a sheet shape, cooling and solidifying the polyester resin sheet on a casting drum, then longitudinally stretching the polyester resin sheet in the longitudinal direction, and then transversely stretching the longitudinally stretched polyester resin film in the transverse direction. The glass transition temperature of the polyester resin, Tg (° C.), the crystallinity of the film after the longitudinal stretching, Xc (%), the crystallization temperature of the film after the longitudinal stretching, Tc (° C.), film surface temperature at the entrance of the stretching zone of a transverse stretching apparatus 30, Ts (° C.), and film surface temperature at the exit of the stretching zone of the transverse stretching apparatus 30, Te (° C.), satisfy: 3≦Xc≦20; Tg−10≦Ts≦Tc+20; and Tc−10≦Te≦Tc+80.
摘要:
In the method for producing a bi-axially oriented thermoplastic resin film, the longitudinal draw ratio X in a longitudinal drawing step is in the range of from 2.8 times to 3.5 times, and the transverse draw ratio Y in a transverse drawing step is in the range of from 3.8 times to 4.8 times. The expression: X≧0.25Y+2.0+(T−(Tg+50))/400, is satisfied where T° C. represents the temperature of the thermoplastic resin film in the transverse drawing step in a tenter 28 and Tg° C. represents the glass transition temperature of the thermoplastic resin film.
摘要:
Electromagnetic waves radiated when a formed polyester film 18 is longitudinally drawn while one surface of the front and rear surfaces of the polyester film 18 is being heated by a radiant heater 30, are composed of such a wavelength band that a thermal energy of 20% or more and 50% or less of the total thermal energy radiated onto the one surface of the polyester film 18 can transmit from the one surface to the other surface. Thereby, even in the case where the film is longitudinally drawn while one surface of the film is being heated in the longitudinal drawing step, a curl is not easily generated in the film.
摘要:
One aspect of the present invention provides a method for production of a polyester resin film comprising melt extruding a polyester resin into a sheet shape, cooling and solidifying the polyester resin sheet on a casting drum, then longitudinally stretching the polyester resin sheet in a longitudinal direction, and then passing the longitudinally stretched polyester resin film through a transverse stretching apparatus to transversely stretch the longitudinally stretched polyester resin film in a transverse direction, wherein Xc, Tc, Ts and Te satisfy the formulas of: Tc≦(Ts+Te)/2+2.66Xc≦Tc+60 (1) and 2≦Xc≦30 (2), in which Xc (%) indicates a crystallinity of the film after the longitudinal stretching, Tc (° C.) indicates a crystallization temperature of the film after the longitudinal stretching, Ts (° C.) indicates a film surface temperature at an entrance of a stretching zone of the transverse stretching apparatus, and Te (° C.) indicates a film surface temperature at an exit of the stretching zone of the transverse stretching apparatus.
摘要:
According to the present invention, a cellulose acylate film having high thickness precision and no streaks can be formed by producing a film with a cellulose acylate resin by means of the polishing roller method, and a high-performance optical film, which is free from the retardation distribution, can be produced by subsequently stretching the cellulose acylate film thus obtained within a magnification range from 1 or more and 2.5 or less.
摘要:
According to the present invention, the adaptability to producing the cellulose acylate film and the surface properties of the cellulose acylate film produced by means of the melt film-forming method can be remarkably improved. Accordingly, there is also improved the surface properties of a stretched cellulose acylate film produced by stretching such an unstretched cellulose acylate film.
摘要:
According to the present invention, a cellulose acylate film having high thickness precision and no streaks can be formed by producing a film with a cellulose acylate resin by means of the polishing roller method, and a high-performance optical film, which is free from the retardation distribution, can be produced by subsequently stretching the cellulose acylate film thus obtained within a magnification range from 1 or more and 2.5 or less.
摘要:
The present invention provides a method for producing a cellulose acylate film which can prevent the generation of foreign matter problems and can produce a high-quality film. A cellulose acylate resin is molten in a twin-screw extruder and extruded from a die to form a cellulose acylate film. The average residence time of the resin in the extruder is set at 5 minutes or less.
摘要:
The present invention provides a method for producing a thermoplastic film which makes it possible to improve the optical properties of the thermoplastic film obtained by stretching and a thermoplastic film manufactured thereby. The transverse stretching section in which a cellulose acylate film is transversely stretched includes: a preheating zone, a transverse stretching zone, a cooling zone and a thermal relaxation zone, and the cellulose acylate film having been cooled in the cooling zone is immediately subjected to thermal relaxation treatment in the thermal relaxation zone.
摘要:
There is provided a method for producing a thermoplastic film, which can suppress the occurrence of residual strain in the film caused by the polishing roller method to prevent the occurrence of stretch non-uniformity in stretching operation and provide a film that has excellent optical characteristics. The molten resin extruded from a die into a sheet is fed between a pair of polishing rollers and cooled while being held and pressed between them so that a cellulose acylate film is formed. The surface of the polishing roller is made up of a fluorine resin.