Patents by Inventor Koji Tasaka
Koji Tasaka 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).
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Patent number: 8952600Abstract: A circularly polarizing plate has a polarizer and two ?/4 plates (T1, T2) bonded respectively onto both sides of the polarizer so as to face each other, the circularly polarizing plate is characterized in that the in-plane retardation values Ro of the ?/4 plates (T1) and the ?/4 plates (T2) satisfy (a) to (c) below in an environment with a temperature of 23° C. and RH of 55%. (a) The in-plane retardation value Ro of the ?/4 plates (T1), when measured within the range of 450 to 650 nm, is 3.0 to 20.0 nm smaller than the in-plane retardation value Ro of the ?/4 plates (T2). (b) The in-plane retardation value Ro of the ?/4 plates (T1) (450) falls within the range of 110 to 140 nm. (c) The in-plane retardation value Ro of the ?/4 plates (T2) (650) falls within the range of 145 to 165 nm.Type: GrantFiled: July 20, 2012Date of Patent: February 10, 2015Assignee: Konica Minolta, Inc.Inventors: Rieko Ren, Koji Tasaka, Kouji Tashiro
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Publication number: 20140319508Abstract: In order to provide an organic electroluminescent display device which does not exhibit redness in reflected external light, and exhibits little fluctuation in the hue of a black image as a result of changes in environmental temperature and differences in the light emitting state, the organic electroluminescent display device according to the present invention comprises, in order from the viewing side, a protective film, a polarizer, a ?/4 phase difference film, and an organic electroluminescent element, and is characterized in that the ?/4 phase difference film satisfies formulas (1) and (2) below. Ro(450)<Ro(550)<Ro(650)??Formula (1) 0.90<photoelastic coefficient ratio(450/650)value<1.Type: ApplicationFiled: November 7, 2012Publication date: October 30, 2014Inventors: Norie Tanihara, Rieko Ren, Koji Tasaka, Yukihito Nakazawa, Kenji Mishima, Midori Kogure
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Publication number: 20140225499Abstract: A circularly polarizing plate has a polarizer and two ?/4 plates (T1, T2) bonded respectively onto both sides of the polarizer so as to face each other, the circularly polarizing plate is characterized in that the in-plane retardation values Ro of the ?/4 plates (T1) and the ?/4 plates (T2) satisfy (a) to (c) below in an environment with a temperature of 23° C. and RH of 55%. (a) The in-plane retardation value Ro of the ?/4 plates (T1), when measured within the range of 450 to 650 nm, is 3.0 to 20.0 nm smaller than the in-plane retardation value Ro of the ?/4 plates (T2). (b) The in-plane retardation value Ro of the ?/4 plates (T1) (450) falls within the range of 110 to 140 nm. (c) The in-plane retardation value Ro of the ?/4 plates (T2) (650) falls within the range of 145 to 165 nm.Type: ApplicationFiled: July 20, 2012Publication date: August 14, 2014Applicant: Konica Minolta, Inc.Inventors: Rieko Ren, Koji Tasaka, Kouji Tashiro
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Patent number: 8580358Abstract: A cellulose ester film containing a polyester represented by Formula (1) or (2), wherein an in-plane retardation value (Ro) is 0 to 5 nm and a retardation value in a thickness direction (Rt) is ?20 to 10 nm, Ro and Rt being measured at 23° C. and 55% RH: B1-(G-A-)mG-B1??Formula (1) wherein B1: monocarboxylic acid, G: dihydric alcohol, A: dibasic acid, B1, G and A contain no aromatic ring, m: repeat number, plural B1 may be the same or different, and plural G may be the same or different; and B2-(A-G-)nA-B2??Formula (2) wherein B2: monoalcohol, G: dihydric alcohol, A: dibasic acid, provided that none of B2, G and A contains an aromatic ring, n: repeat number, plural B2 may be the same or different, and plural G may be the same or different.Type: GrantFiled: June 23, 2006Date of Patent: November 12, 2013Assignee: Konica Minolta Opto, Inc.Inventors: Takashi Takebe, Kunio Shimizu, Koji Tasaka, Shigeki Oka
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Patent number: 7924379Abstract: A liquid crystal display comprising: a brightness enhancing film, polarizing plate (A), a liquid crystal cell, polarizing plate (B) laminated in that order, Wherein (i) polarizing plate (A) has a polarizing plate protective film facing the brightness enhancing film; (ii) the polarizing plate protective film is a cellulose ester film; (iii) an in-plane retardation value Ro(550) of the of the cellulose ester film represented by Formula (I) is 0 to 5 nm; and (iv) a retardation value in a thickness direction Rt(550) of the of the cellulose ester film represented by Formula (II) is ?15 to 15 nm, Ro(550)=(Nx?Ny)×d??Formula (I) Rt(550)={(Nx+Ny)/2?Nz}×d.Type: GrantFiled: August 25, 2006Date of Patent: April 12, 2011Assignee: Konica Minolta Opto, Inc.Inventor: Koji Tasaka
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Patent number: 7854864Abstract: A manufacturing method of an optical film provided with a convexoconcave structure, comprises the steps of: coating a resin solution including a first resin solved by a solvent onto an endless or roll-like mold provided with a convexoconcave structure, and forming a resin solution layer on the mold; laminating a film substrate onto the resin solution layer to make a laminated film before the solvent in the resin solution layer is completely dried, the film substrate including a second resin, which is capable of absorbing the solvent or is soluble by the solvent; and peeling the laminated film from the mold before the solvent in the laminated film is completely dried.Type: GrantFiled: April 19, 2007Date of Patent: December 21, 2010Assignee: Konica Minolta Opto, Inc.Inventors: Akira Sato, Masaru Iwagaki, Hirokazu Sato, Shigeto Ohmori, Kazuhiro Miyazawa, Takashi Murakami, Hirokazu Koyama, Nobuo Kubo, Koji Tasaka, Shigeki Oka
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Patent number: 7740919Abstract: A manufacturing method of a cellulose ester film satisfying the relationships, Nx>Ny>Nz, and 0.8?Rt/R0?3.5, the method comprising casting a cellulose ester dope containing a solvent of a good solvent and a poor solvent on a support to form a web; peeling the web from the support; transporting the peeled web (step D0); holding the edges in the transverse direction of the web (step A); stretching the resulting web in the transverse direction while applying a tension; reducing the tension in the transverse direction of the web; and drying the stretched web, wherein the residual solvent content of the web is 5 to 90% by weight at the beginning in the step A, and the residual poor solvent content in the residual solvent content of the web is from 15 to 95% by weight at the terminal point in the Step D0.Type: GrantFiled: March 20, 2007Date of Patent: June 22, 2010Assignee: Konica CorporationInventors: Koji Tasaka, Hiroki Umeda, Noriyasu Kuzuhara, Takatoshi Yajima
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Patent number: 7709067Abstract: A cellulose ester film comprising a compound represented by Formula (1): Formula (1) B-(G-A)n-G-B, wherein B represents a benzene monocarboxylic acid residue; G represents an alkylene glycol residue having 2-12 carbon atoms, an aryl glycol residue having 6-12 carbon atoms, or an oxyalkylene glycol residue having 4-12 carbon atoms; A represents an alkylene dicarboxylic acid residue having 4-12 carbon atoms or an aryldicarboxylic acid residue having 6-12 carbon atoms; and n represents an integer of 1 or more.Type: GrantFiled: May 1, 2006Date of Patent: May 4, 2010Assignee: Konica Minolta Opto, Inc.Inventors: Takahiro Takagi, Isamu Michihata, Noriyasu Kuzuhara, Koichi Saito, Koji Tasaka, Hiroki Umeda, Minori Tamagawa, Shinji Inagaki
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Patent number: 7599028Abstract: A polarizing plate used in a vertical alignment mode liquid crystal display comprising a liquid crystal cell is disclosed, wherein the polarizing plate comprises a polarizing film and a mixed fatty acid cellulose ester film with optical biaxiality provided between the polarizing film and the liquid crystal cell, and wherein the mixed fatty acid cellulose ester film has a retardation in plane R0 of from 31 to 120 nm, and a retardation in the thickness direction Rt of from 60 to 300 nm, in which R0 is represented by the following formula (1) and Rt is represented by the following formula (2): R0=(nx?ny)×d??formula (1) Rt={(nx+ny)/2?nz}×d.Type: GrantFiled: December 15, 2006Date of Patent: October 6, 2009Assignee: Konica CorporationInventors: Noriyasu Kuzuhara, Koji Tasaka, Hiroki Umeda, Takatoshi Yajima
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Publication number: 20080129934Abstract: An optical compensation film wherein: (i) molecules of a liquid crystalline compound are oriented in a manner that an average tilt angle of the compounds is not more than 4 degrees; (ii) the orientation is fixed; (iii) Ro(?) values are: at wavelength 589 nm: 40-130 nm; at 600 nm: 35-125 nm; and at 630 nm: 35-120 nm; (iv) Rt(?) valuea are 120-400 nm in ? range of 500-630 cm; and (v) Values of Ro(589), Ro(600) and Ro(630) satisfy the following formulae: 1.0<B<7.0 B=(Ro(589)?Ro(630))/(Ro(600)?Ro(630)).Type: ApplicationFiled: January 23, 2008Publication date: June 5, 2008Applicant: KONICA MINOLTA OPTO, INC.Inventors: Hiroki UMEDA, Takatoshi YAJIMA, Noriyasu KUZUHARA, Koji TASAKA
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Patent number: 7345725Abstract: An optical compensation film wherein: (i) molecules of a liquid crystalline compound are oriented in a manner that an average tilt angle of the compounds is not more than 4 degrees; (ii) the orientation is fixed; (iii) Ro(?) values are: at wavelength 589 nm: 40-130 nm; at 600 nm: 35-125 nm; and at 630 nm: 35-120 nm; (iv) Rt(?) value are 120-400 400 nm in ? range of 500-630 nm; and (v) Values of Ro(589), Ro(600) and Ro(630) satisfy the following formulae: 1.0<B<7.0 B=(Ro(589)?Ro(630))/(Ro(600)?Ro(630)).Type: GrantFiled: July 7, 2004Date of Patent: March 18, 2008Assignee: Konica Minolta Opto, Inc.Inventors: Hiroki Umeda, Takatoshi Yajima, Noriyasu Kuzuhara, Koji Tasaka
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Patent number: 7306832Abstract: A manufacturing method of a cellulose ester film satisfying the relationships, Nx>Ny>Nz, and 0.8?Rt/R0?3.5, the method comprising casting a cellulose ester dope containing a solvent of a good solvent and a poor solvent on a support to form a web; peeling the web from the support; transporting the peeled web (step D0); holding the edges in the transverse direction of the web (step A); stretching the resulting web in the transverse direction while applying a tension; reducing the tension in the transverse direction of the web; and drying the stretched web, wherein the residual solvent content of the web is 5 to 90% by weight at the beginning in the step A, and the residual poor solvent content in the residual solvent content of the web is from 15 to 95% by weight at the terminal point in the Step D0.Type: GrantFiled: October 14, 2004Date of Patent: December 11, 2007Assignee: Konica CorporationInventors: Koji Tasaka, Hiroki Umeda, Noriyasu Kuzuhara, Takatoshi Yajima
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Publication number: 20070252293Abstract: A manufacturing method of an optical film provided with a convexoconcave structure, comprises the steps of: coating a resin solution including a first resin solved by a solvent onto an endless or roll-like mold provided with a convexoconcave structure, and forming a resin solution layer on the mold; laminating a film substrate onto the resin solution layer to make a laminated film before the solvent in the resin solution layer is completely dried, the film substrate including a second resin, which is capable of absorving the solution or is soluble by the solvent; and peeling the laminated film from the mold before the solvent in the laminated film is completely dried.Type: ApplicationFiled: April 19, 2007Publication date: November 1, 2007Applicant: KONICA MINOLTA OPTO, INC.Inventors: Akira SATO, Masaru IWAGAKI, Hirokazu SATO, Shigeto OHMORI, Kazuhiro MIYAZAWA, Takashi MURAKAMI, Hirokazu KOYAMA, Nobuo KUBO, Koji TASAKA, Shigeki OKA
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Publication number: 20070178252Abstract: A manufacturing method of a cellulose ester film satisfying the relationships, Nx>Ny>Nz, and 0.8?Rt/R0<3.5, the method comprising casting a cellulose ester dope containing a solvent of a good solvent and a poor solvent on a support to form a web; peeling the web from the support; transporting the peeled web (step D0); holding the edges in the transverse direction of the web (step A); stretching the resulting web in the transverse direction while applying a tension; reducing the tension in the transverse direction of the web; and drying the stretched web, wherein the residual solvent content of the web is 5 to 90% by weight at the beginning in the step A, and the residual poor solvent content in the residual solvent content of the web is from 15 to 95% by weight at the terminal point in the Step D0.Type: ApplicationFiled: March 20, 2007Publication date: August 2, 2007Applicant: KONICA CORPORATIONInventors: Koji TASAKA, Hiroki UMEDA, Noriyasu KUZUHARA, Takatoshi YAJIMA
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Publication number: 20070116898Abstract: A polarizing plate used in a vertical alignment mode liquid crystal display comprising a liquid crystal cell is disclosed, wherein the polarizing plate comprises a polarizing film and a mixed fatty acid cellulose ester film with optical biaxiality provided between the polarizing film and the liquid crystal cell, and wherein the mixed fatty acid cellulose ester film has a retardation in plane R0 of from 31 to 120 nm, and a retardation in the thickness direction Rt of from 60 to 300 nm, in which R0 is represented by the following formula (1) and Rt is represented by the following formula (2): R0=(nx?ny)×d??formula (1) Rt={(nx+ny)/2?nz}×d??formula (2)Type: ApplicationFiled: December 15, 2006Publication date: May 24, 2007Applicant: KONICA CORPORATIONInventors: Noriyasu Kuzuhara, Koji Tasaka, Hiroki Umeda, Takatoshi Yajima
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Patent number: 7218367Abstract: An optical compensation sheet comprising at least two optically anisotropic layers each formed by orienting an optically anisotropic compound, the orientation direction in the optically anisotropic layer plane of the optically anisotropic compound in the two optically anisotropic layers intersecting each other at an angle of from 80 to 100 degrees, wherein, viewing the two layers from one side of the sheet, one of the two layers, when the compound is uniaxial, is oriented so that a first angle of optic axis of the uniaxial optically anisotropic compound to the sheet plane increases continuously or stepwise in the thickness direction of the sheet, or when the compound is biaxial, is oriented so that a second angle of a direction giving maximum refractive index of the biaxial optically anisotropic compound to the sheet plane increases continuously or stepwise in the thickness direction of the sheet, and the other layer, when the compound is uniaxial, is oriented so that the first angle decreases continuously orType: GrantFiled: March 29, 2001Date of Patent: May 15, 2007Assignee: Konica CorporationInventors: Hiroki Umeda, Noriyasu Kuzuhara, Nobuo Kubo, Sota Kawakami, Nobuyuki Takiyama, Koji Tasaka
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Patent number: 7199848Abstract: An optical compensation film used for a liquid crystal display comprising a support and an optically anisotropic layer is disclosed. The optically anisotropic layer is a layer on which orientation of the liquid crystalline compound is fixed and the support is an optically biaxial cellulose ester film. A polarizing plate used for a liquid crystal display and a liquid crystal display employing the optical compensation film are also disclosed.Type: GrantFiled: July 19, 2001Date of Patent: April 3, 2007Assignee: Konica CorporationInventors: Noriyasu Kuzuhara, Nobuo Kubo, Hiroki Umeda, Nobuyuki Takiyama, Takatoshi Yajima, Koji Tasaka
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Publication number: 20070046872Abstract: A liquid crystal display comprising: a brightness enhancing film, polarizing plate (A), a liquid crystal cell, polarizing plate (B) laminated in that order, Wherein (i) polarizing plate (A) has a polarizing plate protective film facing the brightness enhancing film; (ii) the polarizing plate protective film is a cellulose ester film; (iii) an in-plane retardation value Ro(550) of the of the cellulose ester film represented by Formula (I) is 0 to 5 nm; and (iv) a retardation value in a thickness direction Rt(550) of the of the cellulose ester film represented by Formula (II) is ?15 to 15 nm, Ro(550)=(Nx?Ny)×d??Formula (I) Rt(550)={(Nx+Ny)/2?Nz}×d.Type: ApplicationFiled: August 25, 2006Publication date: March 1, 2007Inventor: Koji Tasaka
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Publication number: 20070048462Abstract: A cellulose ester film containing a polyester represented by Formula (1) or (2), wherein an in-plane retardation value (Ro) is 0 to 5 nm and a retardation value in a thickness direction (Rt) is ?20 to 10 nm, Ro and Rt being measured at 23° C. and 55% RH: B1-(G-A-)mG-B1??Formula (1) wherein B1: monocarboxylic acid, G: dihydric alcohol, A: dibasic acid, B1, G and A contain no aromatic ring, m: repeat number, plural B1 may be the same or different, and plural G may be the same or different; and B2-(A-G-)nA-B2??Formula (2) wherein B2: monoalcohol, G: dihydric alcohol, A: dibasic acid, provided that none of B2, G and A contains an aromatic ring, n: repeat number, plural B2 may be the same or different, and plural G may be the same or different.Type: ApplicationFiled: June 23, 2006Publication date: March 1, 2007Applicant: KONICA MINOLTA OPTO, INC.Inventors: Takashi Takebe, Kunio Shimizu, Koji Tasaka, Shigeki Oka
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Patent number: 7184112Abstract: A polarizing plate used in a vertical alignment mode liquid crystal display comprising a liquid crystal cell is disclosed, wherein the polarizing plate comprises a polarizing film and a mixed fatty acid cellulose ester film with optical biaxiality provided between the polarizing film and the liquid crystal cell, and wherein the mixed fatty acid cellulose ester film has a retardation in plane R0 of from 31 to 120 nm, and a retardation in the thickness direction Rt of from 60 to 300 nm, in which R0 is represented by the following formula (1) and Rt is represented by the following formula (2): R0=(nx?ny)×d??formula (1) Rt={(nx+ny)/2?nz}×d.Type: GrantFiled: December 5, 2005Date of Patent: February 27, 2007Assignee: Konica CorporationInventors: Noriyasu Kuzuhara, Koji Tasaka, Hiroki Umeda, Takatoshi Yajima