Patents by Inventor Hirokazu Niwa

Hirokazu Niwa 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).

  • Patent number: 11964042
    Abstract: Provided is an additive for a chemical agent, which is capable of improving the functions of various chemical agents. The additive for a chemical agent according to an embodiment of the present invention includes a polymer (I) containing 50 mol % to 100 mol % of a structural unit derived from an N-vinyl lactam-based monomer with respect to 100 mol % of structural units derived from all monomers, the additive for a chemical agent having an average particle diameter of 100 ?m or less in a state of having been dried under a reduced pressure of 0.02 MPa or less at 100° C. for 1 hour.
    Type: Grant
    Filed: April 27, 2020
    Date of Patent: April 23, 2024
    Assignee: NIPPON SHOKUBAI CO., LTD.
    Inventors: Yui Ikemoto, Yuko Toba, Masahiro Nakanosho, Hirokazu Niwa
  • Publication number: 20220202688
    Abstract: Provided is an additive for a chemical agent, which is capable of improving the functions of various chemical agents. The additive for a chemical agent according to an embodiment of the present invention includes a polymer (I) containing 50 mol % to 100 mol % of a structural unit derived from an N-vinyl lactam-based monomer with respect to 100 mol % of structural units derived from all monomers, the additive for a chemical agent having an average particle diameter of 100 ?m or less in a state of having been dried under a reduced pressure of 0.02 MPa or less at 100° C. for 1 hour.
    Type: Application
    Filed: April 27, 2020
    Publication date: June 30, 2022
    Applicant: NIPPON SHOKUBAI CO., LTD.
    Inventors: Yui Ikemoto, Yuko Toba, Masahiro Nakanosho, Hirokazu Niwa
  • Patent number: 8119739
    Abstract: The invention provides a retardation film, composed primarily of an acrylic polymer, with transparency, heat resistance, and large retardation. The retardation film of the present invention is composed primarily of an acrylic polymer. The film has an in-plane retardation of from 130 nm to 500 nm, inclusive, per 100 ?m thickness at a wavelength of 589 nm. The film has a total light transmittance of not less than 85%. The retardation film has a glass transition temperature of preferably from 110° C. to 200° C., inclusive. The acrylic polymer, which is the primary component, preferably has a lactone ring structure.
    Type: Grant
    Filed: February 27, 2007
    Date of Patent: February 21, 2012
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Hideo Asano, Akio Naka, Hirokazu Niwa, Tomoyuki Kuwamoto, Hiroyasu Watabe, Yoshiyuki Shiotani
  • Publication number: 20100272971
    Abstract: A novel optical film is provided that exhibits a wavelength dispersion (a reverse wavelength dispersion) such that the birefringence of the film decreases as the wavelength becomes shorter, at least in the visible light range. The optical film includes a layer formed of a resin (A) having a heteroaromatic group or a molecular structure represented by the following formula (1), (2) or (3): where in the formula (1), n is a natural number in the range of 1 to 4, and R1 and R2 each independently represent a hydrogen atom or a methyl group. The optical film exhibits a wavelength dispersion such that the birefringence of the film decreases as the wavelength becomes shorter, at least in the visible light range.
    Type: Application
    Filed: December 26, 2008
    Publication date: October 28, 2010
    Applicant: NIPPON SHOKUBAI CO., LTD.
    Inventors: Takashi Miyai, Yoshiyuki Shiotani, Hideo Asano, Hirokazu Niwa, Susumu Hirama, Satoshi Ishida, Masanori Takaiwa
  • Publication number: 20090135483
    Abstract: The invention provides a retardation film, composed primarily of an acrylic polymer, with transparency, heat resistance, and large retardation. The retardation film of the present invention is composed primarily of an acrylic polymer. The film has an in-plane retardation of from 130 nm to 500 nm, inclusive, per 100 ?m thickness at a wavelength of 589 nm. The film has a total light transmittance of not less than 85%. The retardation film has a glass transition temperature of preferably from 110° C. to 200° C., inclusive. The acrylic polymer, which is the primary component, preferably has a lactone ring structure.
    Type: Application
    Filed: February 27, 2007
    Publication date: May 28, 2009
    Applicant: Nippon Shokubai Co., Ltd.
    Inventors: Hideo Asano, Akio Naka, Hirokazu Niwa, Tomoyuki Kuwamoto, Hiroyasu Watabe, Yoshiyuki Shiotani
  • Patent number: 6294015
    Abstract: The present invention provides a cement admixture and a cement composition, both of which displays little dependence of the water-reducibility upon temperature in that these cement admixture and cement composition involve little slump loss at high temperature and little increase in the amount of addition at low temperature. The cement admixture comprises either or both of the following components: copolymer (A) which includes constitutional unit (I) of general formula (1) below and constitutional unit (II) of general formula (2) below as essential constitutional units and may further include constitutional unit (III) of general formula (3) below, wherein the content of constitutional unit (III) is 45 weight % or less of copolymer (A); and copolymer salt (B) which is obtained by further neutralizing copolymer (A) with an alkaline substance.
    Type: Grant
    Filed: January 1, 1999
    Date of Patent: September 25, 2001
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Akihiko Yamashita, Tsuyoshi Hirata, Tsutomu Yuasa, Hirokazu Niwa
  • Patent number: 6258162
    Abstract: The present invention provides a cement additive which can achieve excellent fluid retainability and has excellent mortar kneadability. The cement additive comprises copolymer (A) having polyalkylene glycol ester unit (I) and carboxylic unit (II) as repeating units, wherein polyalkylene glycol ester unit (I) has an oxyalkylene group with 3 to 7 carbon atoms on an ester bonding moiety.
    Type: Grant
    Filed: September 25, 1999
    Date of Patent: July 10, 2001
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Hirokatsu Kawakami, Hirokazu Niwa, Hiromichi Tanaka, Tsutomu Yuasa, Tsuyoshi Hirata
  • Patent number: 6087418
    Abstract: The present invention provides a cement admixture and a cement composition, both of which displays little dependence of the water-reducibility upon temperature in that these cement admixture and cement composition involve little slump loss at high temperature and little increase in the amount of addition at low temperature. The cement admixture comprises the following essential components: either or both of polymer (A) and polymer salt (AA), wherein polymer (A) includes constitutional unit (I) of general formula (1) below as an essential constitutional unit, and polymer salt (AA) is obtained by further neutralizing polymer (A) with an alkaline substance; and either or both of polymer (B) and polymer salt (BB), wherein polymer (B) includes constitutional unit (II) of general formula (2) below as an essential constitutional unit, and polymer salt (BB) is obtained by further neutralizing polymer (B) with an alkaline substance.
    Type: Grant
    Filed: January 1, 1999
    Date of Patent: July 11, 2000
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Akihiko Yamashita, Tsuyoshi Hirata, Tsutomu Yuasa, Hirokazu Niwa