Patents by Inventor Hirofumi KATAMI

Hirofumi KATAMI 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: 20240182756
    Abstract: An object of the present invention is to provide a radiation curable pressure-sensitive adhesive sheet with excellent storage stability, which can suppress the progress of curing during storage and maintain excellent level difference absorbability and stress relaxation properties for a long time. A radiation curable pressure-sensitive adhesive sheet 1 of the present invention has a pressure-sensitive adhesive layer 10 that is cured by irradiation with radiation. The pressure-sensitive adhesive layer 10 contains a photopolymerization initiator 11a and a crosslinking agent 11b, and the curing by irradiation with radiation is curing by a reaction between the photopolymerization initiator 11a and the crosslinking agent 11b. In the radiation curable pressure-sensitive adhesive sheet 1 of the present invention, when the pressure-sensitive adhesive layer 10 is stored at 50° C. for 4 weeks, a rate of change in residual stress (N/cm2) expressed by the following equation is 70% or less.
    Type: Application
    Filed: March 24, 2022
    Publication date: June 6, 2024
    Applicant: NITTO DENKO CORPORATION
    Inventors: Shuhei FUKUTOMI, Hirofumi KATAMI, Shinya YAMAMOTO
  • Publication number: 20230227699
    Abstract: A method for producing a pressure-sensitive adhesive sheet of the present invention includes: forming a pressure-sensitive adhesive layer 10 formed of a transparent, light-cured base pressure-sensitive adhesive material on a support S1; irradiating the pressure-sensitive adhesive layer 10 with an ultraviolet ray U to cure the pressure-sensitive adhesive layer; providing a solution 12 of an ultraviolet absorbing agent 11; applying the solution 12 to one of opposite surfaces of the cured pressure-sensitive adhesive layer 10a to cause the ultraviolet absorbing agent 11 contained in the solution 12 to infiltrate from the one surface in a thickness direction of the pressure-sensitive adhesive layer 10a; and drying the pressure-sensitive adhesive layer 10a.
    Type: Application
    Filed: March 24, 2021
    Publication date: July 20, 2023
    Applicant: NITTO DENKO CORPORATION
    Inventors: Hirotaka OHARA, Hirofumi KATAMI, Takahiro NONAKA
  • Publication number: 20230220248
    Abstract: An object of the present invention is to provide a pressure-sensitive adhesive composition that enables a pressure-sensitive adhesive layer to be formed, wherein the pressure-sensitive adhesive layer has a low dielectric constant, is excellent in level difference conformability and transparency while maintaining adhesive strength and adhesion reliability at high temperatures, and suitable for laminating a metal mesh film and the like. The pressure-sensitive adhesive composition of the present invention contains an acrylic polymer (A), a mixture of monomer components constituting the acrylic polymer (A) or a partially polymerized product of a mixture of monomer components constituting the acrylic polymer (A), and a hydrogenated polyolefinic resin (B) that exhibits liquid flowability at 25° C. The pressure-sensitive adhesive composition comprises a branched-chain alkyl group having 10 to 24 carbon atoms as a monomer component.
    Type: Application
    Filed: June 9, 2021
    Publication date: July 13, 2023
    Applicant: NITTO DENKO CORPORATION
    Inventors: Hirofumi KATAMI, Masamichi MATSUMOTO, Takahiro NONAKA
  • Publication number: 20230220247
    Abstract: An object of the present invention is to provide a pressure-sensitive adhesive sheet enables a pressure-sensitive adhesive layer to be formed, wherein the pressure-sensitive adhesive layer has a low dielectric constant, is excellent in level difference conformability while maintaining adhesive strength and adhesion reliability at high temperatures, and suitable for laminating a metal mesh film and the like. The pressure-sensitive adhesive sheet of the present invention is a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer containing an acrylic polymer (A) and a hydrogenated polyolefinic resin (B) that exhibits liquid flowability at 25° C. The pressure-sensitive adhesive layer has a dielectric constant at a frequency of 1 MHz of from 2.3 to 3.5. The pressure-sensitive adhesive sheet has a 180° peel adhesive strength to a glass plate at a tensile speed of 300 mm/minute at 65° C. of 6 N/20 mm or more.
    Type: Application
    Filed: June 9, 2021
    Publication date: July 13, 2023
    Applicant: NITTO DENKO CORPORATION
    Inventors: Hirofumi KATAMI, Masamichi MATSUMOTO, Takahiro NONAKA
  • Publication number: 20230203347
    Abstract: A method for producing a pressure-sensitive adhesive sheet according to the present invention includes: forming a pressure-sensitive adhesive layer 10 formed of a transparent base pressure-sensitive adhesive material on a support S; curing the pressure-sensitive adhesive layer 10; providing a solution 12 of an additive 11; applying the solution 12 to one of opposite surfaces of the cured pressure-sensitive adhesive layer 10a to cause the additive contained in the solution 12 to infiltrate from the one surface in a thickness direction of the pressure-sensitive adhesive layer 10a; and drying the pressure-sensitive adhesive layer 10a.
    Type: Application
    Filed: March 24, 2021
    Publication date: June 29, 2023
    Applicant: NITTO DENKO CORPORATION
    Inventors: Hirofumi KATAMI, Hirotaka OHARA, Shuhei FUKUTOMI, Shinya YAMAMOTO, Takahiro NONAKA
  • Publication number: 20230102451
    Abstract: An object of the present invention is to provide a pressure-sensitive adhesive sheet, an optical member, and a touch panel that enable a pressure-sensitive adhesive layer to be formed, the pressure-sensitive adhesive layer allowing the appearance of a display device and an input device to be unlikely to deteriorate even under low pressure conditions. The pressure-sensitive adhesive sheet has a pressure-sensitive adhesive layer, and the number of the voids having a diameter of 300 ?M or more in the following low pressure test is less than 10, and the number of the voids having a diameter of not less than 50 less than 300 ?M in the following low pressure test is less than 20.
    Type: Application
    Filed: September 23, 2022
    Publication date: March 30, 2023
    Applicant: Nitto Denko Corporation
    Inventors: Masamichi MATSUMOTO, Hirofumi Katami, Sho Takarada, Ryohei Sawazaki, Kazuma Mitsui
  • Publication number: 20230099594
    Abstract: An object of the present invention is to provide a pressure-sensitive adhesive composition that enables a pressure-sensitive adhesive layer to be formed, the pressure-sensitive adhesive layer allowing the appearance of a display device and an input device to be unlikely to deteriorate even under low pressure conditions, a pressure-sensitive adhesive layer, a pressure-sensitive adhesive sheet, an optical member, and a touch panel. The pressure-sensitive adhesive composition of the present invention contains an acrylic polymer (A) and a hydrogenated polyolefinic resin (B). The acrylic polymer (A) contains a (meth)acrylic alkyl ester having an alkyl group having 8 or more carbon atoms as a constituent monomer component. The hydrogenated polyolefinic resin (B) contains a hydrogenated polyolefin.
    Type: Application
    Filed: September 23, 2022
    Publication date: March 30, 2023
    Applicant: NITTO DENKO CORPORATION
    Inventors: Masamichi MATSUMOTO, Hirofumi KATAMI, Sho TAKARADA, Ryohei SAWAZAKI, Kazuma MITSUI
  • Publication number: 20210260851
    Abstract: There is provided an optical laminate that can suppress the deterioration of the optical characteristics of a retardation layer. An optical laminate according to an embodiment of the present invention includes: a UV-absorbing adhesion layer; a protective layer; a polarizer; and a retardation layer. The retardation layer contains a liquid crystal compound. The UV-absorbing adhesion layer and the polarizer are arranged on a viewer side with respect to the retardation layer, and the UV-absorbing adhesion layer contains a base polymer, a UV absorber, and a dye compound whose absorption spectrum has a maximum absorption wavelength present in a wavelength region of from 380 nm to 430 nm.
    Type: Application
    Filed: May 20, 2019
    Publication date: August 26, 2021
    Applicant: NITTO DENKO CORPORATION
    Inventors: Hiroshi Tomohisa, Hirofumi Katami, Hironori Yaginuma
  • Patent number: 10983391
    Abstract: There is provided a polarizing plate with a retardation layer that can achieve an image display apparatus having excellent durability and excellent weatherability, and having an excellent hue. A polarizing plate with a retardation layer according to an embodiment of the present invention includes in this order: a polarizing plate including a protective layer and a polarizer; a retardation layer; and a pressure-sensitive adhesive layer. The protective layer has a light transmittance at a wavelength of 380 nm of 10% or less. The polarizing plate has a light transmittance at a wavelength of 380 nm of 5% or less. The pressure-sensitive adhesive layer has a light transmittance at a wavelength of 405 nm of 5% or less. The polarizing plate with a retardation layer has a light transmittance at a wavelength of 405 nm of 3% or less.
    Type: Grant
    Filed: May 25, 2018
    Date of Patent: April 20, 2021
    Assignee: NITTO DENKO CORPORATION
    Inventors: Takeharu Kitagawa, Hirofumi Katami, Shusaku Goto
  • Patent number: 10852455
    Abstract: A laminate of optical elements comprises a transparent first optical element, a second optical element, and a transparent pressure-sensitive adhesive layer for bonding the first optical element to the second optical element. The pressure-sensitive adhesive layer comprises a base adhesive zone, a transparent refractive index-adjusting zone. The base adhesive zone is made essentially of a transparent base pressure-sensitive adhesive material and formed over a given range from a first principal surface of the pressure-sensitive adhesive layer facing the first optical element, in a thickness direction of the pressure-sensitive adhesive layer. The a transparent, adherent, refractive index-adjusting zone is formed over a given range from a second principal surface of the pressure-sensitive adhesive layer facing the second optical element.
    Type: Grant
    Filed: January 16, 2015
    Date of Patent: December 1, 2020
    Assignee: NITTO DENKO CORPORATION
    Inventors: Toru Umemoto, Hirofumi Katami, Hiroyuki Takao, Takahiro Nonaka, Atsushi Yasui, Takami Hikita
  • Publication number: 20200142255
    Abstract: There is provided a polarizing plate with a retardation layer that can achieve an image display apparatus having excellent durability and excellent weatherability, and having an excellent hue. A polarizing plate with a retardation layer according to an embodiment of the present invention includes in this order: a polarizing plate including a protective layer and a polarizer; a retardation layer; and a pressure-sensitive adhesive layer. The protective layer has a light transmittance at a wavelength of 380 nm of 10% or less. The polarizing plate has a light transmittance at a wavelength of 380 nm of 5% or less. The pressure-sensitive adhesive layer has a light transmittance at a wavelength of 405 nm of 5% or less. The polarizing plate with a retardation layer has a light transmittance at a wavelength of 405 nm of 3% or less.
    Type: Application
    Filed: May 25, 2018
    Publication date: May 7, 2020
    Applicant: NITTO DENKO CORPORATION
    Inventors: Takeharu Kitagawa, Hirofumi Katami, Shusaku Goto
  • Patent number: 10626304
    Abstract: Provided is a polarizing film laminate comprising: an element substrate; a polarizer; a transparent electroconductive layer patterned so as to function as a touch sensor; and a pressure-sensitive adhesive layer, wherein the adhesive layer comprises: a base adhesive zone made of a transparent base pressure-sensitive adhesive material and formed over a given range from the adhesive layer in a thickness direction of the adhesive layer; and a refractive index adjustment zone formed over a given range from the adhesive layer in the thickness direction and comprising the base adhesive material and material infiltrated into the base adhesive material and different from the base adhesive material, the refractive index adjustment zone having an average refractive index greater than a refractive index of the base adhesive material, and wherein the base adhesive material zone of the adhesive layer is located on the side of the element substrate.
    Type: Grant
    Filed: July 20, 2016
    Date of Patent: April 21, 2020
    Assignee: NITTO DENKO CORPORATION
    Inventors: Hirofumi Katami, Atsushi Yasui
  • Patent number: 10569505
    Abstract: Provided is a polarizing film laminate comprising a pressure-sensitive adhesive layer, and a polarizing film wherein the adhesive layer comprises: a base adhesive zone made of a transparent base pressure-sensitive adhesive material and formed over a given range from one principal surface of the adhesive layer in a thickness direction of the adhesive layer; and a refractive index adjustment zone formed over a given range from the other principal surface of the adhesive layer in the thickness direction and comprising the base pressure-sensitive adhesive material and material infiltrated into the base pressure-sensitive adhesive material and different from the base pressure-sensitive adhesive material, the refractive index adjustment zone having an average refractive index greater than a refractive index of the base pressure-sensitive adhesive material, and wherein the base pressure-sensitive adhesive material zone of the pressure-sensitive adhesive layer is located on the side of the polarizing film.
    Type: Grant
    Filed: July 20, 2016
    Date of Patent: February 25, 2020
    Assignee: NITTO DENKO CORPORATION
    Inventors: Hirofumi Katami, Atsushi Yasui
  • Patent number: 10538055
    Abstract: Provided is a polarizing film laminate comprising a pressure-sensitive adhesive layer, and a polarizing film wherein the adhesive layer comprises: a base adhesive zone made of a transparent base pressure-sensitive adhesive material and formed over a given range from one principal surface of the adhesive layer in a thickness direction of the adhesive layer; and a refractive index adjustment zone formed over a given range from the other principal surface of the adhesive layer in the thickness direction and comprising the base pressure-sensitive adhesive material and material infiltrated into the base pressure-sensitive adhesive material and different from the base pressure-sensitive adhesive material, the refractive index adjustment zone having an average refractive index greater than a refractive index of the base pressure-sensitive adhesive material, and wherein the base pressure-sensitive adhesive material zone of the pressure-sensitive adhesive layer is located on the side of the polarizing film.
    Type: Grant
    Filed: July 20, 2016
    Date of Patent: January 21, 2020
    Assignee: NITTO DENKO CORPORATION
    Inventors: Hirofumi Katami, Atsushi Yasui
  • Patent number: 10369768
    Abstract: The present invention provides a cover element having a pressure-sensitive adhesive sheet preliminarily laminated thereto, wherein the pressure-sensitive adhesive sheet comprises a pressure-sensitive adhesive layer in which a refractive index adjustment zone having a refractive index greater than that of a base pressure-sensitive adhesive material thereof is formed over a given range from a surface of the pressure-sensitive adhesive layer in a thickness direction thereof, whereby: in a lamination process of a customer which is a supply destination of the cover element, it becomes possible to eliminate a need to distinguish between obverse and reverse sides of the pressure-sensitive adhesive sheet itself; and, when the cover element is bonded to an optical element through the pressure-sensitive adhesive layer, it becomes possible to suppress internal reflection in a laminate formed of these optical elements.
    Type: Grant
    Filed: July 11, 2016
    Date of Patent: August 6, 2019
    Assignee: NITTO DENKO CORPORATION
    Inventors: Hirofumi Katami, Atsushi Yasui
  • Patent number: 10265927
    Abstract: The present invention provides a transparent electroconductive layer-equipped cover element having a pressure-sensitive adhesive sheet preliminarily laminated thereto, wherein the pressure-sensitive adhesive sheet comprises a pressure-sensitive adhesive layer in which a refractive index adjustment zone having a refractive index greater than that of a base pressure-sensitive adhesive material thereof is formed over a given range from a surface of the pressure-sensitive adhesive layer in a thickness direction thereof, whereby: in a lamination process of a customer which is a supply destination of the transparent electroconductive layer-equipped cover element, it becomes possible to eliminate a need to distinguish between obverse and reverse sides of the pressure-sensitive adhesive sheet itself; and, when the transparent electroconductive layer-equipped cover element is bonded to an optical element through the pressure-sensitive adhesive layer, it becomes possible to suppress internal reflection in a laminate fo
    Type: Grant
    Filed: July 11, 2016
    Date of Patent: April 23, 2019
    Assignee: NITTO DENKO CORPORATION
    Inventors: Hirofumi Katami, Atsushi Yasui
  • Patent number: 10259193
    Abstract: In the case where a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer having a refractive index adjustment zone is provided in such a manner that two PET separators are laminated to opposite surfaces of the pressure-sensitive adhesive layer, it is difficult to distinguish between obverse and reverse sides of the pressure-sensitive adhesive sheet itself. The present invention is directed to solving the above problems and, specifically, to offering a pressure-sensitive adhesive sheet having a refractive index adjustment zone capable of being easily produced at low cost, in a state in which it is preliminarily laminated with a substrate provided with an electroconductive layer, thereby making it possible to resolve complexity in handling (to easily distinguish between one surface defined by the refractive index adjustment zone and the other surface defined by the remaining zone).
    Type: Grant
    Filed: July 11, 2016
    Date of Patent: April 16, 2019
    Assignee: NITTO DENKO CORPORATION
    Inventors: Hirofumi Katami, Toru Umemoto, Hiroyuki Takao, Atsushi Yasui
  • Publication number: 20180319127
    Abstract: Provided is a polarizing film laminate comprising a pressure-sensitive adhesive layer, and a polarizing film wherein the adhesive layer comprises: a base adhesive zone made of a transparent base pressure-sensitive adhesive material and formed over a given range from one principal surface of the adhesive layer in a thickness direction of the adhesive layer; and a refractive index adjustment zone formed over a given range from the other principal surface of the adhesive layer in the thickness direction and comprising the base pressure-sensitive adhesive material and material infiltrated into the base pressure-sensitive adhesive material and different from the base pressure-sensitive adhesive material, the refractive index adjustment zone having an average refractive index greater than a refractive index of the base pressure-sensitive adhesive material, and wherein the base pressure-sensitive adhesive material zone of the pressure-sensitive adhesive layer is located on the side of the polarizing film.
    Type: Application
    Filed: July 20, 2016
    Publication date: November 8, 2018
    Inventors: Hirofumi KATAMI, Atsushi YASUI
  • Patent number: 10072184
    Abstract: A pressure-sensitive adhesive sheet comprises a support and a transparent pressure-sensitive adhesive layer on the support. The pressure-sensitive adhesive layer comprises a base adhesive zone made essentially of a transparent base pressure-sensitive adhesive material and formed over a given range from a first principal surface of the pressure-sensitive adhesive layer in a thickness direction of the pressure-sensitive adhesive layer, and a transparent, adherent, refractive index-adjusting zone formed over a given range from a second principal surface of the pressure-sensitive adhesive layer in the thickness direction, and wherein the refractive index-adjusting zone has a refractive index greater than a refractive index of the base pressure-sensitive adhesive material.
    Type: Grant
    Filed: January 16, 2015
    Date of Patent: September 11, 2018
    Assignee: NITTO DENKO CORPORATION
    Inventors: Hirofumi Katami, Toru Umemoto, Hiroyuki Takao, Takahiro Nonaka, Atsushi Yasui, Takami Hikita
  • Patent number: 10023766
    Abstract: As one sensor layer structure for a capacitive touch panel, a layer structure in which a transparent electroconductive layer is formed on each of opposite surfaces of a single film substrate, so-called GFD structure, is used. In the structure, for sufficiently suppressing internal reflection from the transparent electroconductive layer, it is necessary to employ a technique of forming one or more refractive index adjustment (IM) layers on each of the opposite surfaces of the single film substrate. This causes a problem that production yield is likely to deteriorate, and a production cost is increased. The present invention is directed to solving such a problem and, specifically, to laminating a refractive index adjustment zone-formed pressure-sensitive adhesive layer capable of being produced easily and at low cost, to each transparent electroconductive layer of a double-sided transparent electroconductive film, so as to effectively suppress internal reflection in the resulting laminate.
    Type: Grant
    Filed: July 11, 2016
    Date of Patent: July 17, 2018
    Assignee: NITTO DENKO CORPORATION
    Inventors: Hirofumi Katami, Toru Umemoto, Hiroyuki Takao, Atsushi Yasui