Sumitomo Chemical Company, Limited

Koji Higashi

Akiko Shimizu

Toyokazu Okada

Tadashi Shindo

Takahiro Hishinuma

Takanobu Noguchi

Toshihiro Ohnishi

Taiichi Sakaya

Masato Kuwabara

Toshiya Kuroda

Kazuaki Sakakura

Masaru Honda

Satoshi Taguchi

Makoto Namioka

Michitaka Morikawa

Shuji Kitamura

Nobuo Oi

Kazuya Ogino

Hitoshi Kikui

Keiichi Minakuchi

Kimishige Nakamura

Yutaka Nishii

Shinjiro Kawasaki

Keizo Ichinose

Takuya Sairai

Setsuko Aoki

The present invention provides a transflective film comprising a polymer film having an in-plane phase retardation value of about 30 nm or less and a transflective layer made of an inorganic compound, wherein the transflective layer is coated on the polymer film and a reflectance of the transflective film is from about 10% to about 95%. When an absorption-type polarizer is laminated to the polymer film side of the transflective film, a transflective polarizer is provided. When a reflection-type polarizer is laminated to the transflective layer side of the transflective film, a transflective polarizer used in a system improving luminance is provided. Using these transflective polarizers, a polarizing light source device and a transflective liquid crystal display device are provided.

Transflective film, transflective polarizer, and polarizing light source device and liquid crystal display device using the same

A polarizer is provided which comprises a reflection type polarizer and a dichroic polarizer, each of which is placed so that polarizing transmission axes of the reflection type polarizer and the dichroic polarizer are coincident with each other on the same optical path, wherein the dichroic polarizer has a transmittance &lsqb;T(AP)(&lgr;)&rsqb; of about 44% or more and a polarizing coefficient &lsqb;P(AP)(&lgr;)&rsqb; of about 50.0% or more or wherein the dichroic polarizer has a luminous correction transmittance &lsqb;Y(AP)&rsqb; of about 44% or more and a luminous correction polarizing coefficient &lsqb;P(AP, y)&rsqb; of about 50.0% or more.

Polarizer, polarizing light source device and liquid crystal display

The present invention provides a phase retarder made of a copolymer prepared by polymerizing one non-cyclic olefin monomer (A) selected from ethylene and &agr;-olefin compound having 3 to 20 carbon atoms, one cyclic olefin monomer (B) selected from cyclic olefin compound such as norbornene, and one cyclic vinyl monomer (C) selected from vinyl compound having a cyclic unit made of an aromatic hydrocarbon or an alicyclic hydrocarbon such as styrene or vinylcyclohexane; wherein (1) an amount of the aromatic vinyl monomer is from about 1 to about 20 mol % and a total amount of the non-cyclic olefin monomer (A) and the cyclic olefin monomer (B) is from about 80 to about 99 mol % in case the component (C) is the aromatic vinyl monomer, or (2) an amount of the alicyclic vinyl monomer is from about 80 to about 99 mol % and a total amount of the non-cyclic olefin monomer and the cyclic olefin monomer is from about 1 to about 20 mol % in case the component (C) is the alicyclic vinyl monomer. The present phase retarder makes it possible to conduct uniform polarizing conversion within a wide wavelength range using a single plate.

Phase retarder

A normally white mode twisted nematic liquid crystal display devices having significantly improved viewing angle characteristics of display contrast and gray scale inversion comprising an about 90&deg; twisted nematic liquid crystal cell and a first and a second light polarizing film separately disposed on two sides of said liquid crystal cell, a first and a second optical compensation layer which each comprises at least one optical compensation layer and has almost no refractive index anisotropy in-plane of the optical compensation layer A and has a characteristic wherein a refractive index in the thickness direction of the optical compensation layer A is lower than that in-plane of the optical compensation layer A, and a first and second optical compensation layer B, which each comprises at least one optical compensation layer and has optically positive refractive index anisotropy and has a characteristic wherein a principal optic axis of the optical compensation layer B is tilted 20 to 70&deg; from the normal direction of the optical compensation layer B, wherein said liquid crystal cell, said light polarizing films and said optical compensation layers A and B are laminated in the following order: said first light polarizing film, said first optical compensation layer A, said first optical compensation layer B, said liquid crystal cell, said second optical compensation layer B, said second optical compensation layer A and said second light polarizing film.

Normally white mode twisted nematic liquid crystal display device having improved viewing angle characteristics

A phase retarder film is provided wherein at least one oblique evaporation layer comprising an inorganic dielectric mainly containing TiO.sub.2 is formed on at least one surface of a transparent polymer film with an intermediate layer between, the evaporation layer having positive refractive index anisotropy and a principal optic axis tilted 20 degrees to 70 degrees from a normal direction to said transparent polymer film. The phase retarder film is suitable for improving viewing angle characteristics of the TN-LCD.

Phase retarder film containing TiO.sub.2

A phase retarder film comprising a layer of polyvinyl alcohol or a derivative thereof and a water-swellable layered inorganic compound, wherein the in-plane retardation value is smaller than the retardation value in the thickness direction, sometimes causes durability failures, that is, the layer is peeled off from a transparent resin substrate in high temperature and high humidity environment. Therefore, the present invention provides a phase retarder film which is superior in durability. With respect to a phase retarder film comprising at least one layer containing at least one organic clay compound which can be dispersed in an organic solvent, wherein the in-plane retardation value is smaller than the retardation value in the thickness direction, the durability is remarkably improved.

Phase retarder and liquid crystal display device using the same

As a phase retarder film in which at least one oblique evaporation layer of an inorganic dielectric having positive refractive index anisotropy and having its principal optic axis tilted 20 degrees to 70 degrees from the direction of the normal to the film is formed on at least one surface of a transparent polymer film with an intermediate layer between, a large area film is easily and inexpensivly obtained.

Phase retarder film

Disclosed is a phase retarder film made of a thermoplastic resin having an in-plane retardation of 50 to 300 nm and a ratio of the in-plane retardation to the retardation normal to the plane of not less than 0.5, but not more than 1.8, a process for the production thereof and a laminate phase retarder film using said phase retarder film above.

By using an optically anisotropic film having the optical axis substantially parallel to the normal line of the film and comprising a polymer of a liquid crystal oligomerhaving positive anisotropy of refractive index and showing nematic or smectic phase, or by lamining the optically anisotropic film and a transparent or semitransparent polymer film, or by combining the optically anisotropic film with a uniaxially oriented retardation film, it is possible to obtain a composite retardation plate with a large viewing angle, and this retardation plate can be applied to a liquid crystal display device.

Optically anisotropic material, process for producing it, and

A phase retarder film made of a thermoplastic resin having an in-plane retardation of 50 to 300 nm and a ratio of the in-plane retardation to the retardation normal to the plane of not less than 0.5 but not more than 1.8, a process for the production thereof and a laminate phase retarder film using said phase retarder film above.

Process for making a phase retarder film

A phase retarder including a layered inorganic compound-containing sheet or layered inorganic compound-containing film, the inorganic compound being selected from the group consisting of a clay mineral, a chalcogen compound, a zirconium phosphate compound, an oxyacid salt of a transition metal, a layered polysilicate, a metal oxyhalogenide, and an intercalary decoration thereof intercalated with ions or molecules between crystalline layer units, the inorganic compound having a mean particle size of 5000 nm or less and a stratified structure with a plurality of crystalline layer units wherein the phase retarder has a refractive index in the plane of the phase retarder that is different from a refractive index in the thickness direction of the phase retarder.

Layered inorganic compound-containing phase retarder

A process for continuously producing a phase retarder film or sheet comprising continuously supplying a stretched thermoplastic resin film or sheet to a heating zone in parallel with the stretching direction of the film or sheet and heating the film or sheet to a temperature not lower than the glass transition temperature of the resin while applying pressure to the surface of the film or sheet passing through the heating zone, thereby continuously subjecting the film or sheet to thermal relaxation while suppressing the expansion of the film or sheet in a direction parallel to the surface of the film or sheet and perpendicular to the stretching axis. According to the present invention, a phase retarder film or sheet having a low angular dependence of retardation can be produced continuously. By using the phase retarder film(s) or sheet(s) thus obtained as optical compensator(s), the viewing angle characteristics of liquid crystal display devices can remarkably be improved.

Process for producing phase retarder film

A liquid crystal device with a compensator made of a layered inorganic compound sheet or film in which a refractive index in the plane and a refractive index in the thickness direction are different from each other. The layered inorganic compound may be smectite group minerals. The layered inorganic compound has a mean particle size of 500 nm or less. The phase retarder is employed in a liquid crystal device.

Liquid crystal device with phase retarder having layered inorganic

A process for producing a phase retarder film or sheet, which comprises subjecting a stretched thermoplastic resin film or sheet to thermal relaxation at a temperature not lower than the glass transition temperature of the thermoplastic resin to shrink the film or sheet in the stretching axis direction while suppressing the expansion of the film or sheet in a direction parallel to the film or sheet surface and perpendicular to the stretching axis.

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Takatsuki, Japan

Koji Higashi