Patents by Inventor Makoto Okawara

Makoto Okawara 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).

  • Ink composition and recording method using the same
    Patent number: 5952048
    Abstract: An ink composition contains a carrier medium and charged particles containing a coloring agent, which ink composition satisfies at least one condition of condition A or B: condition A that the specific charge quantity of the charged particles is in a range of 10 to 1,000 .mu.C/g with a positive or negative polarity; and condition B that the specific resistance of the ink composition is 10.sup.10 .OMEGA.cm or more; and ink-jet recording methods using the ink composition are proposed.
    Type: Grant
    Filed: July 22, 1997
    Date of Patent: September 14, 1999
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuo Tsubuko, Nobutaka Kinoshita, Tsuyoshi Asami, Akihiko Gotoh, Kazuhiko Umemura, Kazuyo Mizuno, Makoto Okawara
  • Non-aqueous type resin dispersion and electrophotographic developer containing said resin
    Patent number: 4764447
    Abstract: This invention relates to a non-aqueous type resin dispersion obtained by polymerizing a polymerizable composition containing at least monomer A represented by the general formula (I), ##STR1## (wherein, R.sup.1 represents --H or --CH.sub.3, X represents --COOC.sub.n H.sub.2n+1 or --OCOC.sub.n H.sub.2n+1, and n represents an integer of 6-20), monomer B represented by the general formula (II), ##STR2## (wherein, R.sup.2 and R.sup.3 represent --H or --CH.sub.3 and m represents an integer of 1-20), and monomer C having a carboxyl group or a glycidyl group in the presence of a polymerization initiator in an aliphatic hydrocarbon solvent.
    Type: Grant
    Filed: July 8, 1986
    Date of Patent: August 16, 1988
    Assignee: Ricoh Co., Ltd.
    Inventors: Kazuo Tsubuko, Shinichi Kuramoto, Kayoko Nagai, Makoto Okawara, Hajime Takanashi
  • Non-aqueous type resin and electrophotographic developer containing the same
    Patent number: 4634651
    Abstract: This invention relates to a non-aqueous type resinous composition obtained by polymerizing a polymerizable composition containing at least monomer A represented by the general formula (I), ##STR1## (wherein R represents --H or --CH.sub.3, X representing --COOC.sub.n H.sub.2n+1 or --O--CO--C.sub.n H.sub.2n+1, and n representing an integer of 6-20) and monomer B represented by the general formula (II), ##STR2## (wherein R represents --H or --CH.sub.3, n representing an integer of 1-20, and M representing --H, Na, K, Mg, Mn, Ca, Li, Al or Co) in the presence of a polymerization initiator in an aliphatic hydrocarbon solvent.
    Type: Grant
    Filed: August 23, 1985
    Date of Patent: January 6, 1987
    Assignee: Ricoh Co., Ltd.
    Inventors: Makoto Okawara, Kazuo Tsubuko
  • Liquid developer for use in electrophotography
    Patent number: 4388395
    Abstract: A liquid developer for use in electrophotography is disclosed which is prepared by dispersing a toner consisting essentially of a pigment or dye and a resin in a carrier liquid having a high insulating property and a low dielectric constant, wherein said resin is a nonaqueous dispersed resin obtained by effecting, in a nonaqueous solvent comprising an aliphatic hydrocarbon, the steps of:(a) copolymerizing (1) a monomer A having the general formula I: ##STR1## [wherein R is H or --CH.sub.3, and A is --COOC.sub.n H.sub.2n+1 or --OC.sub.n H.sub.
    Type: Grant
    Filed: January 15, 1982
    Date of Patent: June 14, 1983
    Assignee: Ricoh Co., Ltd.
    Inventors: Kazuo Tsubuko, Junichiro Hashimoto, Shinichi Kuramoto, Makoto Okawara
  • Process for preparing an .alpha.-cyanoacrylate
    Patent number: 4328170
    Abstract: A process for producing an .alpha.-cyanoacrylate which comprises reacting a cyanoacetate with formaldehyde in the presence of a catalyst and a solvent, wherein a compound having phase transfer catalytic activity is used as the catalyst.
    Type: Grant
    Filed: October 25, 1979
    Date of Patent: May 4, 1982
    Assignee: Matsumoto Seiyaku Kogyo Kabushiki Kaisha
    Inventors: Makoto Okawara, Yukihisa Takaoka, Makoto Kameyama, Iwakichi Sugiyama
  • Method of preparing transition metal complex catalysts
    Patent number: 3933770
    Abstract: There is provided a method of preparing transition metal complex catalysts combined with organic high polymers.
    Type: Grant
    Filed: March 20, 1974
    Date of Patent: January 20, 1976
    Assignee: Tokyo Institute of Technology
    Inventors: Sakuji Ikeda, Atsumu Ozaki, Makoto Okawara, Tsutomu Mizoroki, Masahiro Uchino, Hideki Shirakawa, Noboru Kawata