Toray Industries, Inc.

Sumitomo Electric Industries, Limited

Kenji Tsunashima

Takashi Mimura

Seizo Aoki

Masaru Suzuki

Tetsuya Tsunekawa

Toshiya Yoshii

Hirokazu Kurome

Takashi Sumiya

Katsuya Toyoda

Toshihiko Hiraoka

Hideyuki Yamauchi

Katsutoshi Miyakawa

Takuji Higashioji

Masaaki Kotoura

Atsuhiko Soda

Hiroshi Kuboyama

Masahiro Kimura

Ryosuke Hata

Masayuki Hirose

Minoru Yoshida

Katsutoshi Ando

Jun Sakamoto

Shosuke Yamanouchi

Kiyokazu Nakamura

Tetsuya Machida

Shiro Imai

Masanobu Morikawa

Hidehito Minamizawa

Takeo Fukuyama

Toshiya Ieki

Mototada Fukuhara

Kazuo Matsuura

Seiya Sugiura

Nobutsugu Chigira

Hotsuma Okasaka

Michihiko Tanaka

Hiroyuki Ikeuchi

Shunichi Osada

Kenji Kida

Satoshi Horiuchi

Hiroshi Yoshimura

Tatsuya Ito

Masaharu Toyama

Akiko Yamamoto

Katsumasa Osaki

Yukio Kawatsu

Masanao Sugioka

Tetsuo Ikegami

Morishige Sonoda

Yukio Ota

Yasuji Nakahara

Kouichi Adachi

The object of the present invention is to provide a method for producing a polyester film excellent in rigidity, toughness, dimensional stability, electric properties, etc. and less in thickness fluctuation and surface defects, hence very suitable as a film for various industrial materials such as magnetic recording media, capacitors, heat transfer ribbons and thermal mimeographic stencil paper. The first method of the present invention is a method for producing a polyester film, in which a film made of a resin mainly composed of a polyester is simultaneously biaxially stretched by a simultaneously biaxially stretching tenter oven, comprising the step of effecting small-ratio stretching at an area stretching ratio of 1.0005 to 3.0 times three times or more, to achieve a total area stretching ratio of 25 to 150 times, and the second method of the present invention is a method for producing a polyester film, in which a film made of a resin mainly composed of a polyester is stretched using a simultaneously biaxially stretching tenter oven, comprising the step of effecting a series of operation consisting of stretching and subsequent relaxation twice to less than 10000 times, to achieve a total area stretching ratio of 25 to 150 times.

Polyester film and a production method thereof

Disclosed are a liquid-crystalline resin laminated film comprising a liquid-crystalline resin layer and a non-liquid-crystalline thermoplastic resin layer laminated on at least one surface of the liquid-crystalline resin layer, and having an interlayer adhesiveness of at least 30 N/cm; and a liquid-crystalline resin laminated film comprising a liquid-crystalline resin layer and a non-liquid-crystalline thermoplastic resin layer laminated on at least one surface of the liquid-crystalline resin layer, and satisfying T &gE;T wherein T and T indicate the thermal deformation temperature of the non-liquid-crystalline thermoplastic resin layer and that of the liquid-crystalline resin layer, respectively, measured through thermal mechanical analysis (TMA). These are obtained by forming a non-liquid-crystalline thermoplastic resin layer on at least one surface of a liquid-crystalline resin layer through co-extrusion, followed by stretching the resulting laminated film.

Liquid crystal resin laminated film, method for manufacturing the same, and circuit board comprising liquid crystal resin laminated film

Polyester film and production method thereof

Method and apparatus for producing thermoplastic resin film which allows a biaxially oriented polyester film to be formed at a high speed of 400 m/min or more. In the method, a molten thermoplastic resin film is brought into contact with a cooling medium, to be cooled and solidified, for producing a cast film. The method is characterized by keeping the surface temperature of the cooling medium in the region immediately before the melt reaching position at not lower than the glass transition temperature and not higher than the melting point of the thermoplastic resin. The apparatus is characterized by a cooling medium having a heater and a cooler to ensure that the surface temperature of the cooling medium in the region immediately before the melt reaching position is kept at the requisite temperature, and by a surface temperature of the cooling drum in the region immediately before the film leaving position being maintained lower than the glass transition temperature of the thermoplastic resin.

Method of producing thermoplastic resin films and apparatus for producing the same

A polyester film, comprising a non-liquid crystal polyester (A) and a copolyester (B) containing mesogen groups in the main chain to form a phase separated structure in the non-liquid crystal polyester (A), and the dispersed domains of the copolyester (B), having forms to satisfy the following formulae (1) and (2):

Polyester film and a production process thereof

A novel polyester film and a process for its preparation are disclosed wherein said film is composed of (a) liquid crystal polyester; (b) non-liquid crystal polyester; and (c) fiberizer capable of substantially fiberizing said liquid crystal polyester (a). Said polyester film shows remarkable improvements in various properties compared with the prior art polyester films: polyester film according to the present invention exhibits: (a) a high modulus of elasticity; (b) a high toughness; (c) a small content of: (1) oligomer, (2) thermal decomposition products and (3) gelation products; and (d) excellent electrical properties, so that this film can be used as a base film for electrical insulating material, capacitors, magnetic recording mediums, etc.

Polyester film and process for the preparation thereof

A method of thermally laminating a substrate with a polyester film characterized in that said film has a melting point of 150-250.degree. C., contains 0.01-1% by weight of diethylene glycol component and not more than 0.8% by weight of cyclic trimers, and has an intrinsic viscosity �.eta.! of not less than 0.7. The film has good formability and physical properties such as impact resistance, which are hitherto not attained, and the film is excellent in adhesiveness and taste characteristics, so that the film is suited as a wrapping material and as an inner liner of containers.

Polyester film for thermal lamination

Heat-sensitive mimeograph stencil

Biaxially oriented polyester film and process for production thereof

A reflector used in a surface light source comprising a white polyester film in which fine voids are formed and whose apparent specific gravity is in the range of 0.5 to 1.2. The reflectance of the polyester film can be increased by the fine voids. When the reflector having a high reflectance is used in a surface light source having a side light system, a bright scope of, for example, a liquid crystal display easy to see can be obtained.

Polyester film reflector for a surface light source

A thermoplastic resin film wherein the variation in thickness of the film in the longitudinal direction is not more than 5% and the ratio 'Pw1/PwT' of the sum of spectral intensities of wave-number components present in the wave-number range of 0.15 to 0.45 (1/m) (Pw1) to the sum of spectral intensities of the full wave-number range (PwT) determined when a wave form of the variation in thickness is subjected to analysis of Fourier transformation is not more than 0.20, and wherein the variation in thickness of the film in the longitudinal direction is not more than 5% and the ratio 'Pw2/PwT' of the sum of spectral intensities of wave-number components present in the wave-number range of 1.00 to 2.00 (1/m) (Pw2) to the sum of spectral intensities of the full wave-number range (PwT) is not more than 0.15. In such a film, the uniformity in thickness can remarkably improved, and snaking and wrinkles in post processing can be prevented.

Thermoplastic resin film

A film suitable as a base of image transfer material for thermal recording or a heat-sensitive mimeograph stencil is disclosed. The laminated film of the present invention comprises a coating layer on at least one surface of a polyester film, which coating layer contains as a major component a wax-based composition and has protrusions with length/width ratios of not less than 3 at a density of not less than 20 protrusions/100 .mu.m.sup.2. The film of the present invention, when used as a base of an image transfer material for thermal recording or as a film for heat-sensitive mimeograph stencil, the running property is good, abrasion and staining of the head are very small, shedding of ink when the ink is applied does not occur, and the adhesion of the ink, clearness of printed characters, anti-sticking property, holing property and clearness of printing are excellent.

Laminated polyester film for heat-sensitive image transfer material

A polyester film, which is substantially non-oriented and whose main component is polyethylene terephthalate, is formed into a shape for example, a package, at a condition causing no yield point. The formation ability of the polyester film for forming is improved, and a formed body having a good uniformity in thickness can be obtained. Further, the range of the temperature condition causing no yield point can be enlarged by laminating a PET-system polyester, which originally tends to cause a yield point by itself, onto a polyester having no yield point. In such a laminated polyester film, the slipping property and releasing property from a mold of the film can be improved by specifying the ranges of the degree of crystallinity of each layer, the adhesive force at a high temperature of the film and the surface roughness of the film, and the shape of a formed body can be improved.

Process for forming a polyester film

This invention relates to a polyester film suited for use in optical recording medium. The polyester film of the present invention has a modulus of photoelasticity of not more than 0.9.times.10.sup.-3 mm.sup.2 /kgf, a maximum surface roughness Rt of not more than 100 nm and a mean interval Sm between adjacent surface projections of not less than 20 .mu.m, so that light scattering and interference are not caused, and optical strain is not generated even when a thermal stress or external force is exerted to the film. Thus, the polyester film of the present invention can be used as the supporting layer or cover layer of optical recording media such as optical cards, optical disks and optical recording tapes.

Polyester film having specific surface properties

Growing community of inventors

Kyoto, Japan

Kenji Tsunashima