Patents by Inventor Seiji Homma

Seiji Homma 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).

  • Heat stable, pigmented sintered material comprising a boride, carbide, silicide, nitride or phosphide
    Patent number: 6284036
    Abstract: The present invention relates to a process for pigmenting a porous sintered material comprising boride, carbide, silicide, nitride or phosphide compounds by applying a solution of a soluble pigment derivative to the non-coloured sintered material and regenerating the organic pigment by heating, whereby the organic pigment is deposited into the sintered material's pores, as well as to the new pigmented sintered materials themselves.
    Type: Grant
    Filed: November 8, 1999
    Date of Patent: September 4, 2001
    Assignee: Ciba Specialty Chemicals Corporation
    Inventors: Seiji Homma, Hans-Thomas Schacht, Zhimin Hao
  • Process for pigmenting porous metal oxides and materials pigmented therewith
    Patent number: 6258158
    Abstract: The present invention relates to a process for pigmenting a porous metal oxide by applying a solution of a soluble pigment derivative and regenerating the organic pigment by heating, whereby the organic pigment is deposited into the metal oxide's pores. The invention also relates to pigmented porous metal oxides and materials comprising a solid substrate and a surface layer of a pigmented metal oxide.
    Type: Grant
    Filed: November 8, 1999
    Date of Patent: July 10, 2001
    Assignee: Ciba Specialty Chemicals Corp.
    Inventors: Philippe Bugnon, Seiji Homma, Patrick Verhoustraeten
  • Colored metallic pigment and preparation thereof
    Patent number: 5718753
    Abstract: The instant invention relates to a process for the production of colored metallic pigments, as well as these colored metallic pigments themselves, their use to color high molecular weight organic material in the mass and compositions or masterbatches containing them.The colored metallic pigment consists essentially of multiple loose particles of 0.1-1000 .mu.m size each, said particles comprising a core of a transition metals, metalloid or alloy, preferably an aluminum flake, and a very fine, substantially continuous, uniform and homogeneous layer of organic pigment particles which is directly in contact with the metallic core. The core may be superficially oxidized.The colored metallic pigment is prepared by a vacuum deposition process, said process being performed in an apparatus constructed, modified or charged in such a way that the organic pigment gas flows toward the metallic core.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: February 17, 1998
    Assignee: Ciba Specialty Chemicals Holding, Inc.
    Inventors: Masakazu Suzuki, Hiroshi Nakaminami, Seiji Homma
  • Electrophotographic photoreceptors
    Patent number: 5098810
    Abstract: The present invention provides an electrophotographic photoreceptor consisting essentially of an electrically conductive substrate and a photosensitive layer containing at least one charge transport material selected from the compound shown by formulae (1), (2), (3), (4), and (5): ##STR1## and at least one charge generating material selected from pyrrolopyrrole compounds of formula (6) ##STR2##
    Type: Grant
    Filed: May 24, 1990
    Date of Patent: March 24, 1992
    Assignee: Japat Ltd.
    Inventors: Jin Mizuguchi, Seiji Homma, Hiroshi Yamamoto, Takashi Deno