Patents by Inventor Shaw-Ping Chang

Shaw-Ping Chang 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).

  • Electrostatic toner composition to enhance copy quality by rejection of ghosting and method of manufacturing same
    Patent number: 5981131
    Abstract: An electrostatic developer comprising a mixture of (1) a toner component containing image-forming particles, and (2) particles obtained by subjecting inorganic oxide or organic particles to a hydrophobic treatment with a dimethyl cyclopolysiloxane.
    Type: Grant
    Filed: July 27, 1998
    Date of Patent: November 9, 1999
    Assignee: Mitsubishi Chemical America, Inc.
    Inventors: Kazuhiro Hirama, Kenichi Nakazato, Kenzo Ogata, Kenichi Asajima, Shaw-Ping Chang
  • Electrophotographic polyester toner blends
    Patent number: 4489150
    Abstract: A novel toner composition with improved thermal and rheological properties, improved surface energy, and better frangibility is provided. The toner comprises a thermoplastic polymeric blend and a coloring agent. The polymeric blend is comprised of propoxylated bisphenol-A fumarate and a polyester resin with a chemically bound halogen. A preferred polyester resin with a chemically bound halogen is tetrabromo-bisphenol fumarate polyester. An improved electrophotographic imaging process using the toner particles of the present invention is also provided.
    Type: Grant
    Filed: June 8, 1983
    Date of Patent: December 18, 1984
    Assignee: Ricoh Company, Ltd.
    Inventors: Shaw-Ping Chang, Paul Shieh