Fujifilm Corporation

Fuji Photo Film Company, Limited

Masaaki Otoshi

Kiyokazu Hashimoto

Fumitaka Terai

Takanori Sato

Yasuyuki Hosono

Kazuo Ozaki

Fumiyuki Suzuki

Toshimitu Okutu

Tadahiro Kegasawa

Shinichi Nakai

Tadashi Ueda

Tetsuya Yoshida

Akihide Fujita

One embodiment of the present invention provides a method for producing a stretched cellulose acylate film with an in-plane retardation, Re, of 100 nm or more and a relationship between the thickness direction retardation, Rth, and Re which satisfies Rth&#x3c;(Re/2), by longitudinally stretching an unstretched cellulose acylate film in a longitudinal direction by pulling by means of a difference in circumferential velocity between a pair of rollers, wherein the method is characterized in that the cellulose acylate film is subjected to free-end uniaxial stretching to a longitudinal stretch ratio of 1 to 2 while the film is being heated in a heating oven installed between the pair of rollers at a stretching temperature in the range of Tc&#x2212;10&#xb0; C. to Tc+70&#xb0; C., Tc being the crystallization temperature of the film, and with the temperature difference in the film width direction maintained within 10&#xb0; C.

Stretched cellulose acylate film and process for producing the same

A thermoplastic film is transversely stretched, and then transported in a heat-treating zone () such that the ratio (G/D) of an inter-roll distance (G) to a roll lap length (D) is 0.01 to 3, and the ratio (V/V) of an exit-side transporting speed (V) to an entry-side transporting speed (V) is 0.6 to 0.999. The thermoplastic film is heat-treated in the heat-treating zone () at (Tg&#x2212;20)&#xb0; C. to (Tg+50)&#xb0; C., in which Tg is the glass transition temperature of the film. The heat-treated thermoplastic film exhibits an Rth/Re ratio of at least 0.5 and less than 1, an Rth/Re ratio range of 0.01 to 0.1 in the width direction, and a thermal dimensional change of 0.001% to 0.3% under conditions of 80&#xb0; C. and 200 hours.

Heat treatment of thermoplastic film, and thermoplastic film and method for producing the same

The present invention provides a method for producing a cellulose acylate resin film, comprising the step of, melting a cellulose acylate resin in an extruder and extruding the molten cellulose acylate resin to a die, wherein the step of melting is carried out using a tandem extruder having a first-stage extruder and a second-stage extruder connected in tandem, in order to prevent discoloration and thickness non-uniformity make the film seriously defective for use as an optical film. Because the resin in the form of a powder or flakes is once pelletized in a pelletizing extruder, and then the pellets are melt-extruded in an extruder. This promotes discoloration of the resin, disadvantageously.

Cellulose acylate resin film and method for producing the same

Disclosed is a cellulose acylate film produced according to a melt casting process and having an Re unevenness of from 0 to 10%. When built in a liquid-crystal display device, the film significantly solves the problem of display unevenness and humidity-dependent visibility change.

Cellulose acylate film and method for producing same

An unstretched cellulose acylate film hardly breakable upon stretching can be produced by melt film forming and as a result, a highly oriented stretched cellulose acylate film can be obtained. Using an extruder with a screw compression ratio of 2.5 to 4.5 and an L/D of 20 to 50, a cellulose acylate resin is extruded into a sheet at an extrusion temperature of 190&#xb0; C. to 240&#xb0; C. from a die to a cooling drum, and solidified by cooling to prepare an unstretched cellulose acylate film, which is then stretched to produce a stretched cellulose acylate film.

Cellulose acylate film, method of producing the same, stretched cellulose acylate film and method of producing the same

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.

Method for producing cellulose acylate film and optical compensation film for liquid crystal display plate produced by using the method

According to the present invention, a cellulose acylate film difficult to be broken even if the stretching ratio is increased upon stretching and whose retardation (Re) is easily controllable to a desired value can be produced by melt film forming. Accordingly, a stretched cellulose acylate film highly oriented and having an appropriate retardation (Re) required from liquid crystal display device manufacturers can be produced.

Method for producing cellulose acylate film

A cellulose acylate film showing 10 marks/mor less of adhesion marks and having an in-plane retardation value (Re value) of 0 to 200 nm and a retardation value along the thickness direction (Rth value) of 30 to 500 nm. The cellulose acylate film shows favorable optical uniformity and can provide an improved liquid crystal display.

Cellulose acylate film and method for producing the same

A method is provided for manufacturing a wide band retardation plate which gives uniform phase difference characteristics to incident light over the whole visible wavelength region, and which, as it permits selection of raw materials regardless of whether they have a positive or negative intrinsic double refraction value, allows a wide selection of raw materials. For this purpose, the method comprises a machine direction-stretched film-forming step for transporting and stretching in an identical direction to the transport direction, a Material A of two or more materials having different positive intrinsic double refraction values to form a machine direction-stretched film, a transverse direction-stretched film-forming step for transporting and stretching in a perpendicular direction to the transport direction, a Material B of the aforesaid two or more materials to form a transverse direction-stretched film, and a lamination step for laminating the machine direction-stretched film and the transverse direction-stretched film.

Retardation plate and its manufacturing method, circularly polarizing plate and 1/2 wave plate using same, and a reflective liquid crystal display

This invention provides a method of producing a biaxially stretched polyester film with regulating casting conditions of a polyester film at a high speed so as not to induce surface defects caused by entrapping air microbubbles between a cooling drum and a molten resin sheet, and regulating longitudinal stretching conditions and lateral stretching conditions. The biaxially stretched polyester film is excellent in small thickness variation, resistance to cleavage and improvement in bowing phenomenon, and is particularly suitable for the support of a photographic film.

Method of producing biaxially stretched polyester film

The present invention improves the bowing phenomenon of a biaxially stretched polyester film which comprises stretching the longitudinally stretched cast film laterally at a temperature higher than the glass transition temperature of the polyester film from by 5&deg; C. to by 50&deg; C., staying the laterally stretched film in an intermediate zone for a period from 3 to 30 seconds which has been controlled at a temperature from higher than the lateral stretching temperature by 20&deg; C. or more to lower than a heat setting temperature by 20&deg; C. or less, and then heat-setting at the heat setting temperature which is lower than the melting point of the polyester film from by 30&deg; C. to by 5&deg; C.

A photographic support having good adhesion to a photographic emulsion layer formed thereon without physical surface modification. The support comprises a uniaxially or biaxially stretched polyester film and has at least (1) a main layer containing a polyester and (2) one or two surface layers. At least one of the surface layers comprises a substantially noncrystalline polyester. Furthermore, when used in the form of a roll film, substantially no curling of the support remains upon development.

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Fujinomiya, Japan

Masaaki Otoshi