Patents by Inventor Toshiyuki Umehara
Toshiyuki Umehara 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: 7259803Abstract: A resin sheet that is unlikely to be affected by heat and allows prevention of the occurrence of a crack is provided. A glass fiber cloth-like material is dipped into an epoxy resin solution and subjected to curing, thereby obtaining an epoxy resin-based sheet including the glass fiber cloth-like material. The resin sheet has a haze value of 10% or lower, and preferably, has a light transmittance of 88% or higher, an in-plane retardation of not more than 2 nm, a retardation in a thickness direction of 40 nm, and a surface roughness of not more than 2 ?m.Type: GrantFiled: May 22, 2003Date of Patent: August 21, 2007Assignee: Nitto Denko CorporationInventors: Yuuzou Akada, Toshiyuki Umehara, Nobuyoshi Yagi, Tadaaki Harada, Yoshimasa Sakata, Hidetoshi Yoshitake
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Patent number: 7060346Abstract: Resin sheets which are thin and lightweight and have an antiglare function for preventing the so-called ghost phenomenon in which an illuminating light, such as fluorescent light or sunlight, or part of the surrounding objects, e.g., the keyboarder, is reflected on the display and/or a light-diffusing function for preventing the glittering attributable to an illuminating light or to the built-in backlight in the liquid crystal display; processes for producing the resin sheets; and liquid crystal displays using the resin sheets. One of the resin sheets comprises a gas barrier layer, a base layer, and two hard coat layers respectively as the outermost layers, wherein one of the hard coat layers has recesses and protrusions on the outer surface thereof and at least one of the hard coat layers contains transparent particles.Type: GrantFiled: December 5, 2001Date of Patent: June 13, 2006Assignee: Nitto Denko CorporationInventors: Nobuyoshi Yagi, Toshiyuki Umehara
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Publication number: 20050237307Abstract: A surface-treated film, a transparent rigid layer and a transparent relaxing layer are laminated in this order to form a transparent laminate. Particularly, the transparent relaxing layer is made of an adhesive. The dynamic storage modulus G? of the transparent rigid layer at 20° C. is not lower than 2×108 Pa. On the other hand, the dynamic storage modulus G? of the transparent relaxing layer at 20° C. is not higher than 1×107 Pa. The transparent laminate is directly laminated onto a visual surface side (pen-input side) of a liquid crystal panel provided as an image display panel so that the transparent relaxing layer is placed inward. Thus, a pen-input image display device is produced.Type: ApplicationFiled: February 5, 2004Publication date: October 27, 2005Inventors: Yoshihiro Hieda, Tomonori Noguchi, Ikuo Kawamoto, Toshiyuki Umehara, Minoru Miyatake
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Patent number: 6942906Abstract: A resin sheet containing dispersed particles which is thin and lightweight, and has excellent mechanical strength and light-diffusing properties. The resin sheets may be used in liquid crystal displays. A resin sheet having a hard coat layer, an epoxy resin layer containing 100 parts by weight of the resin to 200 parts by weight of a diffuser having a refractive index different from that of the epoxy resin and having an average particle diameter from 0.2 to 100 ?m, and a thin metal layer as a reflecting layer, wherein the diffuser localizes so as to have a concentration distribution in the direction of the thickness of the epoxy resin layer. A resin sheet having dispersed particles which is obtained by superposing a reflecting layer, an inorganic gas barrier layer, or a color filter layer thereon. A process for producing the resin sheet having a color filter layer.Type: GrantFiled: November 6, 2003Date of Patent: September 13, 2005Assignee: Nitto Denko CorporationInventors: Yoshimasa Sakata, Toshiyuki Umehara, Kiichi Shimodaira, Kazutaka Hara, Yoshihiro Kitamura, Katsuhiro Nakano
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Patent number: 6936313Abstract: A resin sheet containing dispersed particles which is thin, lightweight, and has excellent mechanical strength and light-diffusing properties. The resin sheets may be used in liquid crystal displays. A resin sheet having a hard coat layer, an epoxy resin layer containing 100 parts by weight of the resin to 200 parts by weight of a diffuser having a refractive index different from that of the epoxy resin and having an average particle diameter from 0.2 to 100 ?m, and a thin metal layer as a reflecting layer, wherein the diffuser localizes so as to have a concentration distribution in the direction of the thickness of the epoxy resin layer. A resin sheet having dispersed particles which is obtained by superposing a reflecting layer, an inorganic gas barrier layer, or a color filter layer thereon. A process for producing the resin sheet having a color filter layer.Type: GrantFiled: March 5, 2002Date of Patent: August 30, 2005Assignee: Nitto Denko CorporationInventors: Yoshimasa Sakata, Toshiyuki Umehara, Kiichi Shimodaira, Kazutaka Hara, Yoshihiro Kitamura, Katsuhiro Nakano
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Publication number: 20050129877Abstract: A resin sheet that is unlikely to be affected by heat and allows prevention of the occurrence of a crack is provided. A glass fiber cloth-like material is dipped into an epoxy resin solution and subjected to curing, thereby obtaining an epoxy resin-based sheet including the glass fiber cloth-like material. The resin sheet has a haze value of 10% or lower, and preferably, has a light transmittance of 88% or higher, an in-plane retardation of not more than 2 nm, a retardation in a thickness direction of 40 nm, and a surface roughness of not more than 2 ?m.Type: ApplicationFiled: May 22, 2003Publication date: June 16, 2005Inventors: Yuuzou Akada, Toshiyuki Umehara, Nobuyoshi Yagi, Tadaaki Harada, Yoshima Sakata, Hidetoshi Yoshitake
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Patent number: 6818263Abstract: A resin sheet which comprises a base layer containing particles dispersed therein and hence has excellent dimensional stability; a resin sheet which comprises a base layer containing particles dispersed therein and hence has excellent light diffusion properties; resin sheets which comprise either of those resin sheets containing dispersed particles and a reflecting layer, inorganic gas barrier layer, and color filter layer respectively superposed thereon; and a liquid crystal display using any of these resin sheets containing dispersed particles. Some of the resin sheets containing dispersed particles comprise a base layer comprising a thermoplastic resin or thermoset resin and dispersed therein an inorganic oxide having an average particle diameter of 1 to 100 nm, the amount of the inorganic oxide being 0.1 to 23% by weight based on the weight of the base layer.Type: GrantFiled: May 31, 2001Date of Patent: November 16, 2004Assignee: Nitto Denko CorporationInventors: Kiichi Shimodaira, Toshiyuki Umehara, Nobuyoshi Yagi, Yoshimasa Sakata, Yoshihiro Kitamura, Katsuhiro Nakano
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Publication number: 20040121087Abstract: A resin sheet which has abase layer containing particles dispersed therein, is thin and lightweight, and has excellent mechanical strength and light-diffusing properties; a resin sheet containing dispersed particles which is obtained by superposing a reflecting layer or an inorganic gas barrier layer on that resin sheet; a resin sheet containing dispersed particles which is obtained by superposing a color filter layer on that resin sheet; processes for producing the resin sheet having a color filer layer; and liquid crystal displays employing those resin sheets. One of those resin sheets has a hard coat layer, an epoxy resin layer containing, per 100 parts by weight of the resin, up to 200 parts by weight of a diffuser having a refractive index different from that of the epoxy resin and having an average particle diameter of from 0.Type: ApplicationFiled: November 6, 2003Publication date: June 24, 2004Applicant: NITTO DENKO CORPORATIONInventors: Yoshimasa Sakata, Toshiyuki Umehara, Kiichi Shimodaira, Kazutaka Hara, Yoshihiro Kitamura, Katsuhiro Nakano
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Patent number: 6740266Abstract: An epoxy optical sheet comprising a hardened sheet of an epoxy resin and another resin layer formed on one side thereof. The sheet has a retardation of 5 nm or less, an average thickness of 500 &mgr;m or less, a thickness accuracy of ±10% or less, a glass transition temperature of 170° C. or above, and a smooth surface. The epoxy optical sheet is made by a continuous process which comprises: successively forming a strippable resin layer on a support having a smooth surface; successively spreading an epoxy resin coating solution comprising an epoxy resin, a hardener, a hardening accelerator, and a leveling agent, on the resin layer in the form of a sheet; followed by a hardening treatment, thereby forming a hardened sheet adhering to the resin layer; and, at the same time, recovering the hardened sheet together with the resin layer from the support.Type: GrantFiled: September 11, 2002Date of Patent: May 25, 2004Assignee: Nitto Denko CorporationInventors: Hiroshi Sugawa, Kazuhiko Tahara, Shuzo Fujiwara, Nobuyoshi Yagi, Yoshimasa Sakata, Toshiyuki Umehara
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Patent number: 6565975Abstract: A cured resin plate which is reduced in undulation and has excellent flatness even when having a thickness of 100 &mgr;m or larger or a size exceeding 2 inches; and a process for efficiently mass-producing the resin plate. The process comprises spreading a resinous coating fluid A on a support (5) having a smooth surface to form an unsolidified or solidified coating layer, spreading thereon a resinous coating fluid B which is the same as or different from the coating fluid A to form two or more superposed layers of the coating fluid B, and solidifying the layers (12, 22, and 42) separately or simultaneously to thereby form superposed resin layers (1, 2, and 4) adhered to each other which comprise two or more adjacent cured resin layers (1 and 2). The multilayered resin plate comprises superposed layers adhered to each other which are composed of a thermoset epoxy resin layer and superposed thereon a thermoset epoxy resin layer having a smaller thickness than that layer.Type: GrantFiled: December 15, 2000Date of Patent: May 20, 2003Assignee: Nitto Denko CorporationInventors: Toshiyuki Umehara, Yoshimasa Sakata
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Publication number: 20030012957Abstract: An epoxy optical sheet having a thickness of 500 &mgr;m or less, a high thickness accuracy, a small retardation and an excellent heat resistance; and a process by which the optical sheet can be efficiently produced.Type: ApplicationFiled: September 11, 2002Publication date: January 16, 2003Applicant: NITTO DENKO CORPORATIONInventors: Hiroshi Sugawa, Kazuhiko Tahara, Shuzo Fujiwara, Nobuyoshi Yagi, Yoshimasa Sakata, Toshiyuki Umehara
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Patent number: 6500518Abstract: An epoxy optical sheet having a thickness of 500 &mgr;m or less, a high thickness accuracy, a small retardation and an excellent heat resistance; and a process by which the optical sheet can be efficiently produced.Type: GrantFiled: May 6, 1999Date of Patent: December 31, 2002Assignee: Nitto Denko CorporationInventors: Hiroshi Sugawa, Kazuhiko Tahara, Shuzo Fujiwara, Nobuyoshi Yagi, Yoshimasa Sakata, Toshiyuki Umehara
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Publication number: 20020160127Abstract: A resin sheet which has a base layer containing particles dispersed therein, is thin and lightweight, and has excellent mechanical strength and light-diffusing properties; a resin sheet containing dispersed particles which is obtained by superposing a reflecting layer or an inorganic gas barrier layer on that resin sheet; a resin sheet containing dispersed particles which is obtained by superposing a color filter layer on that resin sheet; processes for producing the resin sheet having a color filer layer; and liquid crystal displays employing those resin sheets. One of those resin sheets has a hard coat layer, an epoxy resin layer containing, per 100 parts by weight of the resin, up to 200 parts by weight of a diffuser having a refractive index different from that of the epoxy resin and having an average particle diameter of from 0.Type: ApplicationFiled: March 5, 2002Publication date: October 31, 2002Inventors: Yoshimasa Sakata, Toshiyuki Umehara, Kiichi Shimodaira, Kazutaka Hara, Yoshihiro Kitamura, Katsuhiro Nakano
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Publication number: 20020119298Abstract: An epoxy optical sheet having a thickness of 500 &mgr;m or less, a high thickness accuracy, a small retardation and an excellent heat resistance; and a process by which the optical sheet can be efficiently produced.Type: ApplicationFiled: May 6, 1999Publication date: August 29, 2002Inventors: HIROSHI SUGAWA, KAZUHIKO TAHARA, SHUZO FUJIWARA, NOBUYOSHI YAGI, YOSHIMASA SAKATA, TOSHIYUKI UMEHARA
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Publication number: 20020102367Abstract: A resin sheet which comprises a base layer containing particles dispersed therein and hence has excellent dimensional stability; a resin sheet which comprises a base layer containing particles dispersed therein and hence has excellent light diffusion properties; resin sheets which comprise either of those resin sheets containing dispersed particles and a reflecting layer, inorganic gas barrier layer, and color filter layer respectively superposed thereon; and a liquid crystal display using any of these resin sheets containing dispersed particles.Type: ApplicationFiled: May 31, 2001Publication date: August 1, 2002Inventors: Kiichi Shimodaira, Toshiyuki Umehara, Nobuyoshi Yagi, Yoshimasa Sakata, Yoshihiro Kitamura, Katsuhiro Nakano
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Patent number: 6410606Abstract: A process for producing a natural rubber for a pressure-sensitive adhesive, which comprises decreasing a molecular weight of an unmasticated natural rubber by the action of a peptizing agent while dissolving the unmasticated natural rubber in an organic solvent, and a natural rubber-based pressure-sensitive adhesive composition comprising a natural rubber having a weigh average molecular weight Mw of 700,000 or less obtained by the process.Type: GrantFiled: January 24, 2001Date of Patent: June 25, 2002Assignee: Nitto Denko CorporationInventors: Tomohide Banba, Yoshihiro Minamizaki, Isao Hirose, Toshiyuki Umehara
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Publication number: 20020068134Abstract: Resin sheets which are thin and lightweight and have an antiglare function for preventing the so-called ghost phenomenon in which an illuminating light, such as fluorescent light or sunlight, or part of the surrounding objects, e.g., the keyboarder, is reflected on the display and/or a light-diffusing function for preventing the glittering attributable to an illuminating light or to the built-in backlight in the liquid crystal display; processes for producing the resin sheets; and liquid crystal displays using the resin sheets. One of the resin sheets comprises a gas barrier layer, a base layer, and two hard coat layers respectively as the outermost layers, wherein one of the hard coat layers has recesses and protrusions on the outer surface thereof and at least one of the hard coat layers contains transparent particles.Type: ApplicationFiled: December 5, 2001Publication date: June 6, 2002Applicant: NITTO DENKO CORPORATIONInventors: Nobuyoshi Yagi, Toshiyuki Umehara
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Publication number: 20010053425Abstract: A cured resin plate which is reduced in undulation and has excellent flatness even when having a thickness of 100 &mgr;m or larger or a size exceeding 2 inches; and a process for efficiently mass-producing the resin plate. The process comprises spreading a resinous coating fluid A on a support (5) having a smooth surface to form an unsolidified or solidified coating layer, spreading thereon a resinous coating fluid B which is the same as or different from the coating fluid A to form two or more superposed layers of the coating fluid B, and solidifying the layers (12, 22, and 42) separately or simultaneously to thereby form superposed resin layers (1, 2, and 4) adhered to each other which comprise two or more adjacent cured resin layers (1 and 2). The multilayered resin plate comprises superposed layers adhered to each other which are composed of a thermoset epoxy resin layer and superposed thereon a thermoset epoxy resin layer having a smaller thickness than that layer.Type: ApplicationFiled: December 15, 2000Publication date: December 20, 2001Inventors: Toshiyuki Umehara, Yoshimasa Sakata
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Publication number: 20010034384Abstract: A process for producing a natural rubber for a pressure-sensitive adhesive, which comprises decreasing a molecular weight of an unmasticated natural rubber by the action of a peptizing agent while dissolving the unmasticated natural rubber in an organic solvent, and a natural rubber-based pressure-sensitive adhesive composition comprising a natural rubber having a weigh average molecular weight Mw of 700,000 or less obtained by the process.Type: ApplicationFiled: January 24, 2001Publication date: October 25, 2001Inventors: Tomohide Banba, Yoshihiro Minamizaki, Isao Hirose, Toshiyuki Umehara
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Publication number: 20010010857Abstract: A resin substrate for optical use is described, which comprises a multilayer structure (5, 6, 7) having a surface roughness Ra of 0.8 nm or lower on at least one side and having an average thickness of from 100 to 800 &mgr;m.Type: ApplicationFiled: January 26, 2001Publication date: August 2, 2001Inventors: Nobuyoshi Yagi, Minoru Miyatake, Toshiyuki Umehara, Yoshimasa Sakata, Kiichi Shimodaira