Patents by Inventor Tsubuko Kazuo

Tsubuko Kazuo 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: 5328794
    Abstract: A fluorine-containing graft copolymer prepared by a step (i) of polymerizing a monomer having formula (I) and an unsaturated carboxylic acid or a monomer having a glycidyl group to obtain a copolymer, ##STR1## wherein R represents --H or --CH.sub.3 group; and A represents --COOC.sub.n H.sub.2n+1 or OC.sub.n H.sub.2n+1, in which n is an integer of 6 to 20; a step (ii) of esterifying the resulting copolymer by using a monomer having a glycidyl group in the case where a constituting monomer of the above copolymer is an unsaturated carboxylic acid, or by using an unsaturated carboxylic acid in the case where a constituting monomer of the above copolymer is a monomer having a glycidyl group; and a step (iii) of graft-polymerizing a monomer comprising at least fluoroalkyl acrylate or fluoroalkyl methacrylate on the above esterified copolymer. In addition, a toner comprising a coloring agent and a resin component which comprises the above-mentioned fluorine-containing graft copolymer is disclosed.
    Type: Grant
    Filed: March 16, 1993
    Date of Patent: July 12, 1994
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsubuko Kazuo, Shinichi Kuramoto, Kazuhiko Umemura, Toshihiko Takahashi, Hidemi Uematsu