Patents by Inventor Ruicheng Ran

Ruicheng Ran 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: 6025408
    Abstract: Novel thioxanthone derivatives and mixtures thereof and methods of making and using the same are disclosed. The novel thioxanthone derivatives can be liquid at room temperature and display highly active photoinitiation and photopolymerization properties.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: February 15, 2000
    Assignee: First Chemical Corporation
    Inventors: Eric Lee Williams, Ruicheng Ran, Charles Uriah Pittman, Jr., Joseph Stanton Bowers, Jr., August John Muller
  • Patent number: 5254665
    Abstract: Ammeline-melamine-formaldehyde resins (AMFR) containing from 5-100% ammeline were synthesized by the polymerization of the sodium salt of ammeline, which must be made in advance, melamine, and formaldehyde in basic medium (pH=9.2-10.0). In this copolymerization, it is possible to make uniform random AMFR resins with any mole ratio of ammeline salt to melamine. Preferably the AMFR resin will contain from 5-10% ammeline. As an "ionomer" or a "polyelectrolyte," both the solid and solution properties of these resins (such as melting temperature, solubility, solution stability, etc.) depended directly on the mole ratio of ammeline to melamine and formaldehyde, and/or on the pH value of the medium in which the AMFR resin was present. The pH value controlled the ammeline rings/ammeline's salt groups and also the ratio of unprotonated to protonated amino groups on both the melamine and ammeline rings.
    Type: Grant
    Filed: August 24, 1992
    Date of Patent: October 19, 1993
    Assignee: Melamine Chemicals, Inc.
    Inventors: George M. Crews, Shen Ji, Charles U. Pittman, Jr., Ruicheng Ran