Patents by Inventor Kunihiko Hada

Kunihiko Hada 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: 7989389
    Abstract: The present invention provides a heat-sensitive recording material having a support, a heat-sensitive color-developing layer containing a leuco dye and a developer, and a protective layer, the heat-sensitive color-developing layer and the protective layer being formed on the support, wherein carboxylic-acid-modified polyvinyl alcohol with a weight average degree of polymerization of 100 to 400 and a modification degree of 0.2 mol % to 1.0 mol % is used as a dispersing agent for dispersing the leuco dye.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: August 2, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Kunihiko Hada, Yoshikazu Kaneko, Michiyo Fukushima, Kazuyuki Uetake
  • Publication number: 20090176647
    Abstract: The present invention provides a heat-sensitive recording material having a support, a heat-sensitive color-developing layer containing a leuco dye and a developer, and a protective layer, the heat-sensitive color-developing layer and the protective layer being formed on the support, wherein carboxylic-acid-modified polyvinyl alcohol with a weight average degree of polymerization of 100 to 400 and a modification degree of 0.2 mol % to 1.0 mol % is used as a dispersing agent for dispersing the leuco dye.
    Type: Application
    Filed: March 12, 2008
    Publication date: July 9, 2009
    Inventors: Kunihiko HADA, Yoshikazu Kaneko, Michiyo Fukushima, Kazuyuki Uetake
  • Patent number: 7419935
    Abstract: A heat-sensitive recording material comprising on one surface of a substrate a heat-sensitive coloring layer comprising a leuco dye and a color developer, wherein the heat-sensitive recording material comprises a layer which comprises a copolymer of a (meth)acryloyloxyalkylammonium salt and styrene; and the layer which comprises the copolymer of the (meth)acryloyloxyalkylammonium salt and styrene is at least any one of a back layer, an under layer and a protective layer.
    Type: Grant
    Filed: March 13, 2006
    Date of Patent: September 2, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasuhiro Kadota, Takeshi Kajikawa, Kunihiko Hada
  • Publication number: 20060205593
    Abstract: A heat-sensitive recording material comprising on one surface of a substrate a heat-sensitive coloring layer comprising a leuco dye and a color developer, wherein the heat-sensitive recording material comprises a layer which comprises a copolymer of a (meth)acryloyloxyalkylammonium salt and styrene; and the layer which comprises the copolymer of the (meth)acryloyloxyalkylammonium salt and styrene is at least any one of a back layer, an under layer and a protective layer.
    Type: Application
    Filed: March 13, 2006
    Publication date: September 14, 2006
    Inventors: Yasuhiro Kadota, Takeshi Kajikawa, Kunihiko Hada
  • Patent number: 5703006
    Abstract: A thermosensitive recording medium is disclosed which includes a support, and a thermosensitive color-developing layer formed on the support and containing a leuco dye having a melting point of at least 200.degree. C. and a color developer having a melting point of at least 180.degree..
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: December 30, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasutomo Mori, Motoi Orihara, Kunihiko Hada, Shuji Miyamoto
  • Patent number: 5646088
    Abstract: A thermosensitive recording material having a high degree of background whiteness, superior light resistance without coloring of the background when exposed to the light, and a method of producing a stable coating liquid or forming a thermosensitive coloring layer and a protective layer are provided.
    Type: Grant
    Filed: February 15, 1996
    Date of Patent: July 8, 1997
    Assignee: Ricoh Co., Ltd.
    Inventors: Kunihiko Hada, Yasutomo Mori, Motoi Orihara, Shuji Miyamoto
  • Patent number: 5536697
    Abstract: A thermal printing material having a substrate and a recording layer on the substrate, the recording layer containing a leuco compound color and a developer for developing the leuco compound color when heated, the developer comprising a compound represented by the formula: ##STR1## wherein each of R1 through R8 indicates a hydrogen atom or an alkyl group having from 1-5 carbon atoms, and n indicates an integer from 6-14.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: July 16, 1996
    Assignee: Ricoh Company, Ltd.
    Inventors: Kunihiko Hada, Motoo Tasaka, Shuji Miyamoto
  • Patent number: 5409881
    Abstract: A thermosensitive recording material composed of a support, a thermosensitive recording layer formed on the support, capable of producing colored images by heating, and a protective layer formed on the thermosensitive recording layer, which contains as a resin component a copolymer resin obtained by copolymerization of arylamide or methacrylamide, acrylonitrile, and a vinyl monomer having a carboxyl group, or a copolymer resin of a core-shell emulsion type obtained by copolymerization of acrylamide and/or methacrylamide in the presence of a seed emulsion of an acryl-based copolymer or methacryl-based copolymer, and as a crosslinking agent a compound having two or more alkyleneimino groups, a carbodiimide compound, a methyl ethyl ketoxime compound, or bis(.beta.-hydroxyethyl)sulfone.
    Type: Grant
    Filed: December 23, 1992
    Date of Patent: April 25, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasutomo Mori, Mitsuru Naruse, Kunihiko Hada, Motoo Tasaka