Patents by Inventor Toshiro Narizuka

Toshiro Narizuka 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: 6043355
    Abstract: A phthalocyanine compound of formula (I): ##STR1## wherein FIGS. 1 to 16 around the phthalocyanine skeleton indicate the positions of carbon atoms in each benzene ring thereof; an oxygen atom is bonded to the carbon atom with position 1 or 4, to the carbon atom with position 5 or 8, to the carbon atom with position 9 or 12, and to the carbon atom with position 13 or 16; R.sup.1 is a fluorine-atom substituted alkyl group; R.sup.2 is an unsubstituted phenyl group or an alkyl-group-substituted phenyl group; R.sup.3 is an unsubstituted alkyl group, a fluorine-atom substituted alkyl group or a hydrogen atom; and M represents Zn, Cu or Ni.
    Type: Grant
    Filed: February 5, 1998
    Date of Patent: March 28, 2000
    Assignees: Ricoh Company, Ltd., Yamada Chemical Co., Ltd.
    Inventors: Toru Yashiro, Masatoshi Taniguchi, Toshiro Narizuka, Hiroaki Tomita
  • Patent number: 5932721
    Abstract: A phthalocyanine compound of formula (1): ##STR1## wherein FIGS. 1 to 16 around the phthalocyanine skeleton indicate the positions of carbon atoms, an oxygen atom is bonded to the carbon atom with position 1 or 4, to the carbon with position 5 or 8, to the carbon atom with position 9 or 12, and to the carbon atom with position 13 or 16, R.sup.1 is a fluorine-atom substituted alkyl group, R.sup.2 is an unsubstituted phenyl group or an alkyl-group-substituted phenyl group, R.sup.3 is an unsubstituted alkyl group, a fluorine-atom substituted alkyl group or a hydrogen atom, and M represents VO or TiO.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: August 3, 1999
    Assignee: Ricoh Company, Ltd.
    Inventors: Toru Yashiro, Masatoshi Taniguchi, Toshiro Narizuka
  • Patent number: 5179066
    Abstract: This invention relates to a thermosensitive recording material containing at least one of durene derivative represented by the formula (I): ##STR1## wherein Z represents CH.sub.2 OX or H, X represents an alkyl group, a cycloalkyl group, a substituted or unsubstituted aralkyl group or aryl group, or --COR group where R represents an alkyl group or a substituted or unsubstituted aryl group,in a recording layer which contains a leuco dye and a color-developing agent which reacts with said dye so as to form a color by heating, and the thermosensitive recording material having high color sensitivity can be obtained.
    Type: Grant
    Filed: April 8, 1992
    Date of Patent: January 12, 1993
    Assignees: Yamada Chemical Co., Ltd., Nagase Chemicals Ltd.
    Inventors: Manabu Yamada, Toshiro Narizuka, Katsuhiko Tsunemitsu, Hajime Kawai, Takayuki Kurosaki