Patents by Inventor Nao Murakami

Nao Murakami has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20060072221
    Abstract: The present invention provides a birefringent optical film that allows a liquid crystal display to achieve excellent contrast and a wide viewing angle and does not cause coloring of the liquid crystal display. The birefringent optical film includes at least one birefringent A-layer having a property satisfying nya?nza>nxa or nza>nya>nza and at least one birefringent B-layer having a property satisfying nxb?nyb>nzb.
    Type: Application
    Filed: July 23, 2004
    Publication date: April 6, 2006
    Inventors: Yuuichi Nishikouji, Hiroyuki Yoshimi, Nao Murakami
  • Publication number: 20060055853
    Abstract: The present invention relates to an optical film that is excellent in optical properties and can be produced at low cost. In the optical film formed by laminating a transparent polymer film layer and a birefringent layer of a non-liquid crystalline polymer, the birefringent layer satisfies a condition represented by nx?ny>nz and the in-plane retardation of the transparent polymer film layer is 50 nm or less. In the above formula, nx, ny and nz are the refraction indices in the X-, Y- and Z-axes directions of the birefringent layer, respectively. The X-axis direction is the axial direction in which the refraction index shows a maximum value in the in-plane direction of the birefringent layer, the Y-axis direction is the axial direction perpendicular to the X-axis direction in the plane, and the Z-axis direction is the thickness direction perpendicular to the X- and Y-axes directions.
    Type: Application
    Filed: July 29, 2003
    Publication date: March 16, 2006
    Inventors: Nao Murakami, Hiroyuki Yoshimi, Yuuichi Nishikouji, Masaki Hayashi
  • Publication number: 20050231839
    Abstract: An optical film including a transparent polymer film (b) and a birefringent layer (a) formed of a polymer and laminated above the transparent polymer film (b) is provided. The birefringent layer (a) and the transparent polymer film (b) satisfy the following formula (1), the birefringent layer (a) satisfies the following formulae (2) and (3), and the polymer forming the birefringent layer (a) has a weight-average molecular weight in the range between 10,000 and 400,000 inclusive. ?n(a)>?n(b)×10??(1) 1<(nx?nz)/(nx?ny)??(2) 0.0005??n(a)?0.5??(3) This optical film can prevent the occurrence of iridescence, the occurrence of cracks, and the occurrence of variation in retardation.
    Type: Application
    Filed: May 21, 2003
    Publication date: October 20, 2005
    Applicant: Nitto Denko Corporation
    Inventors: Nao Murakami, Yuuichi Nishikouji, Masaki Hayashi, Hiroyuki Yoshimi
  • Publication number: 20050221023
    Abstract: A polyimide film having a biaxial optical anisotropy and excellent durability is provided. A solution of polyimide having an imidization ratio of 98% to 100% is applied onto a plastic base, and then the solution is dried, thus forming a polyimide coating. Subsequently, the polyimide coating is stretched together with the plastic base so as to satisfy nx>ny>nz, wherein nx and ny indicate a refractive index in a direction exhibiting a maximum refractive index within a plane and that in a direction perpendicular thereto and nz indicates a refractive index in a thickness direction.
    Type: Application
    Filed: December 24, 2003
    Publication date: October 6, 2005
    Inventors: Michie Sakamoto, Yuuichi Nishikouji, Nao Murakami, Masaki Hayashi
  • Publication number: 20050206810
    Abstract: As a polarizing plate with optical compensation function, that is thin and excellent in optical characteristics, the present invention provides a polarizing plate with optical compensation function including at least two optically compensating layers. The optically compensating layers includes: an optically compensating A-layer formed of a polymer film, satisfying conditions represented by formulae (I) and (II) below; and an optically compensating B-layer formed of a non-liquid crystalline polymer film, satisfying conditions represented by formulae (III) to (V) below. 20 (nm)?Rea?300 (nm)??(I) 1.0?Rza/Rea?8??(II) 1 (nm)?Reb?100 (nm)??(III) 5?Rzb/Reb?100??(IV) 1 (?m)?db?20 (?m)??(V) The present invention also provides a liquid crystal display using the polarizing plate.
    Type: Application
    Filed: April 17, 2003
    Publication date: September 22, 2005
    Applicant: Nitto Denko Corporation
    Inventors: Shinichi Sasaki, Nao Murakami, Hiroyuki Yoshimi
  • Publication number: 20050151906
    Abstract: A method of manufacturing a birefringent film is provided, by which a birefringent film including a liquid crystal compound birefringent layer and another birefringent layer can be manufactured so as to have a reduced thickness in a reduced number of process steps. In the manufacturing method, a non-liquid crystal polymer birefringent layer that has been subjected to an aligning treatment is used as an alignment layer for a liquid crystal compound. According to the manufacturing method, the process step of separately preparing an alignment layer and the need for the additional alignment layer can be eliminated, thereby allowing the total thickness of the birefringent film to be reduced.
    Type: Application
    Filed: April 24, 2003
    Publication date: July 14, 2005
    Inventors: Hiroyuki Yoshimi, Yuuichi Nishikouji, Nao Murakami, Masaki Hayashi
  • Publication number: 20050122586
    Abstract: The present invention provides an optical compensation plate having an optical compensation layer in which cracks occurring due to an applied pressure is suppressed. By applying a curable adhesive agent onto at least one surface of the optical compensation layer and curing the adhesive, an anti-cracking layer is formed directly on the surface of the optical compensation layer. The occurrence of cracks in the optical compensation layer can be prevented by this anti-cracking layer. The optical compensation layer preferably is a layer having a cholesteric structure, and the constituent material thereof is preferably a non-liquid crystal polymer formed by polymerizing aligned liquid crystal monomers or an aligned liquid crystal polymer.
    Type: Application
    Filed: January 22, 2003
    Publication date: June 9, 2005
    Applicant: Nitto Denko Corporation
    Inventors: Junichi Adachi, Shuuji Yano, Takashi Yamaoka, Masayuki Kawai, Kanako Wasai, Nao Murakami
  • Publication number: 20050117099
    Abstract: An inclined optical compensation film formed from a non-liquid-crystal polymer, which is useful in a TN mode liquid crystal display. A substrate is coated with a non-liquid-crystal polymer to thereby form a coating film; the non-liquid-crystal polymer of the coating film is inclined and aligned; and the coating film is solidified, thereby forming an inclined optical compensation film. The non-liquid-crystal polymer can be inclined and aligned by, for example, applying external force, such as wind blowing, to the coating film. This inclined optical compensation film exhibits, for example, a birefringence (?n) ranging from 0.001 to 0.5 and thus is useful in a TN mode liquid crystal display, etc.
    Type: Application
    Filed: February 18, 2003
    Publication date: June 2, 2005
    Inventors: Takashi Yamaoka, Nao Murakami, Hiroyuki Yoshimi
  • Publication number: 20050117217
    Abstract: A polarizing plate with an optical compensation layer is provided, which has an excellent peelability and is easy to reattach after mounted on an image display apparatus. A pressure-sensitive adhesive layer satisfying the condition (I) below is formed on both surfaces of an optical compensation layer, and one of the pressure-sensitive adhesive layers is further laminated with a polarizing plate.
    Type: Application
    Filed: June 17, 2003
    Publication date: June 2, 2005
    Inventors: Takashi Yamaoka, Junichi Adachi, Masayuki Kawai, Nao Murakami, Hiroyuki Yoshimi, Shuuji Yano, Kanako Wasai
  • Publication number: 20050099562
    Abstract: The present invention provides a laminated retardation plate that shows an excellent viewing angle property when used in a liquid crystal display, and that can be decreased in thickness. The laminated retardation plate is formed by laminating an optically anisotropic layer (A) made of a polymer having an in-plane retardation of 20-300 nm and a ratio between a thickness direction retardation and the in-plane retardation of not less than 1.0, and an optically anisotropic layer (B) made of a non-liquid crystalline polymer such as polyimide having an in-plane retardation of not less than 3 nm and a ratio between a thickness direction retardation and the in-plane retardation of not less than 1.0. The thus obtained laminated retardation plate shows excellent optical properties, e.g., an in-plane retardation (Re) of 10 nm or more, and a difference between a thickness direction retardation and the in-plane retardation of 50 nm or more.
    Type: Application
    Filed: February 18, 2003
    Publication date: May 12, 2005
    Inventors: Yuuichi Nishikouji, Shinichi Sasaki, Takashi Yamaoka, Nao Murakami, Hiroyuki Yoshimi, Masaki Hayashi
  • Publication number: 20050078245
    Abstract: A polarizing plate with optical compensation function, including a polarizing layer and an optically compensating layer, wherein the optically compensating layer includes an optically compensating A-layer including a stretched polymer film and an optically compensating B-layer including a cholesteric liquid crystal layer.
    Type: Application
    Filed: February 18, 2003
    Publication date: April 14, 2005
    Inventors: Shinichi Sasaki, Takashi Yamaoka, Nao Murakami, Hiroyuki Yoshimi
  • Publication number: 20050074564
    Abstract: A method for preparing an optical film, which comprises applying and developing an application liquid mixture containing a liquid crystal monomer, a chiral agent and a polymerization initiator on an orientation substrate, subjecting the resultant developed layer to a heat treatment, to orient the monomer to a cholesteric structure, and then subjecting the developed layer to a poltmerization treatment, to polymerize the oriented liquid crystal monomer, thereby forming an optical film exhibiting a selective reflection wave length of 100 to 320 nm. An optical film prepared by the above method is reduced in the coloring due to selective reflection.
    Type: Application
    Filed: January 22, 2003
    Publication date: April 7, 2005
    Inventors: Takashi Yamaoka, Shuuji Yano, Junichi Adachi, Masayuki Kawai, Kanako Wasai, Nao Murakami
  • Publication number: 20050058781
    Abstract: It is an object of the present invention to provide a method for manufacturing a birefringent film that can reduce the amount of a remaining solvent in the birefringent film without degrading appearance uniformity or an alignment in its thickness direction. The method of the present invention for manufacturing an optical film includes the steps of coating a base with a polymer solution obtained by dissolving a polyimide-containing polymer in a solvent so as to form a coating film; and drying the coating film so as to form a birefringent film, in which the drying step includes at least two stages of drying processes. The drying step preferably include two stages of the drying processes, and a temperature in the former stage of the drying process is preferably lower than a temperature in the latter stage of the drying process. If adding a step of providing the birefringent film with an anisotropy of a refractive index in an in-plane direction, a birefringent film with an optical biaxiality can be manufactured.
    Type: Application
    Filed: September 15, 2004
    Publication date: March 17, 2005
    Applicant: Nitto Denko Corporation
    Inventors: Masaki Hayashi, Nao Murakami, Yuuichi Nishikouji, Hiroyuki Yoshimi
  • Publication number: 20050030456
    Abstract: The present invention provides a transparent optical film that has excellent optical characteristics for realizing the uniform retardation distribution and restraining rainbow-colored irregularities. The optical film, which is obtained by laminating a birefringent layer (a) on a transparent film (b), satisfies all the following formulae (I), (II) and (III). ?n(a)>?n(b)×10??(I) 1<(nx?nz)/(nx?ny)??(II) 0.0005<?n(a)?0.5??(III) In the above formulae (I), (II) and (III), ?n(a) and ?n(b) denote respectively birefringent indexes of the birefringent layer (a) and the transparent film (b). The signs of nx, ny and nz indicate refractive indexes in an X-axis direction, a Y-axis direction and a Z-axis direction in the birefringent layer (a), respectively.
    Type: Application
    Filed: January 22, 2003
    Publication date: February 10, 2005
    Inventors: Nao Murakami, Takashi Yamaoka, Hiroyuki Yoshimi, Yuuichi Nishikouji, Masaki Hayashi
  • Patent number: 6829026
    Abstract: A laminated phase retarder having: a laminate of a retardation layer A made of a thermoplastic resin exhibiting positive birefringent characteristic and a retardation layer B constituted by an oriented solidified layer of cholesteric liquid crystal exhibiting a selective reflection wavelength range not larger than 350 nm; wherein Re of the laminate is not smaller than 10 nm and Rth−Re of the laminate is not smaller than 50 nm when Re and Rth are given by Re=(nx−ny)×d and Rth=(nx−nz)×d in which nx and ny are in-plane main refractive indices, nz is a thicknesswise refractive index, and d is a layer thickness. A polarizing member having: a laminate of a laminated phase retarder defined above; and a polarizer. A liquid-crystal display device having: a liquid-crystal cell; and a laminated phase retarder or a polarizing member defined above and disposed on at least one of opposite surfaces of the liquid-crystal cell.
    Type: Grant
    Filed: October 7, 2002
    Date of Patent: December 7, 2004
    Assignee: Nitto Denko Corporation
    Inventors: Shinichi Sasaki, Takashi Yamaoka, Nao Murakami, Hiroyuki Yoshimi
  • Patent number: 6819382
    Abstract: By a method for producing a liquid crystal cell substrate having a base and a birefringent layer, which includes producing a precursor layer of the birefringent layer by applying a solution of a polymer that hardens to form the birefringent layer, directly onto one surface of the base, and producing the birefringent layer by hardening the precursor layer, the present invention provides a method for producing a birefringent layer on a liquid crystal cell substrate or a liquid crystal cell substrate of a liquid crystal panel used in a liquid crystal display.
    Type: Grant
    Filed: January 22, 2003
    Date of Patent: November 16, 2004
    Assignee: Nitto Denko Corporation
    Inventors: Takashi Yamaoka, Nao Murakami, Hiroyuki Yoshimi, Tatsuki Nagatsuka
  • Publication number: 20040201805
    Abstract: The present invention provides a birefringent optical film having a high orientation for easily obtaining a desired retardation value and also a small photoelastic coefficient. The birefringent optical film includes at least two kinds of polymer materials.
    Type: Application
    Filed: December 17, 2003
    Publication date: October 14, 2004
    Inventors: Yuuichi Nishikouji, Nao Murakami, Tokio Fujita, Hiroyuki Yoshimi
  • Publication number: 20040202849
    Abstract: The present invention provides a birefringent optical film having a high orientation for easily obtaining a desired retardation value and also a small photoelastic coefficient. The birefringent optical film includes at least two kinds of polymer materials.
    Type: Application
    Filed: December 17, 2003
    Publication date: October 14, 2004
    Inventors: Yuuichi Nishikouji, Nao Murakami, Masaki Hayashi, Hiroyuki Yoshimi
  • Publication number: 20040100599
    Abstract: By a method for producing a liquid crystal cell substrate having a base and a birefringent layer, which includes producing a precursor layer of the birefringent layer by applying a solution of a polymer that hardens to form the birefringent layer, directly onto one surface of the base, and producing the birefringent layer by hardening the precursor layer, the present invention provides a method for producing a birefringent layer on a liquid crystal cell substrate or a liquid crystal cell substrate of a liquid crystal panel used in a liquid crystal display.
    Type: Application
    Filed: January 22, 2003
    Publication date: May 27, 2004
    Inventors: Takashi Yamaoka, Nao Murakami, Hiroyuki Yoshimi, Tatsuki Nagatsuka
  • Patent number: 6717642
    Abstract: A wide viewing angle polarizer having: a polarizing film; and a phase retarder adhesively laminated on at least one surface of the polarizing film through an adhesive layer, the phase retarder being made of a composite phase retarder constituted by a laminate in which a retardation layer B of a cholesteric liquid crystal-oriented solidified layer in a selective reflection wavelength range of not larger than 350 nm is supported by a retardation layer A of a thermoplastic resin exhibiting positive birefringence, the composite phase retarder being formed so that the laminate has Re of not smaller than 10 nm and Rth−Re of not smaller than 50 nm when Re and Rth are defined as Re=(nx−ny)X d and Rth=(nx−nz)X d respectively in which nx and ny are in-plane main refractive indices, nz is a thicknesswise refractive index, and d is a layer thickness.
    Type: Grant
    Filed: October 9, 2002
    Date of Patent: April 6, 2004
    Assignee: Nitto Denko Corporation
    Inventors: Shinichi Sasaki, Takashi Yamaoka, Nao Murakami, Hiroyuki Yoshimi