Patents by Inventor Eui Joon Choi

Eui Joon Choi 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).

  • Publication number: 20110300479
    Abstract: The present invention relates to a toner composition with a broad fusing temperature range and a process for preparing the same. The toner composition according to the present invention creates entanglement between adjacent polymer chains using a non-linear polyester resin having a branch structure, provides elasticity to molten materials by the branch structure when the resin is molten, prevents the molten materials from being transferred to the surface of a roller at a high temperature, and thereby increases the maximum fusing temperature. Therefore, as the average branch number per polyester resin increases, the maximum fusing temperature rises and the fusing temperature range of the toner composition can be widened.
    Type: Application
    Filed: August 28, 2009
    Publication date: December 8, 2011
    Applicant: EXAX TONER, INC
    Inventors: Eui Joon Choi, Hyun Nam Yoon
  • Patent number: 7208255
    Abstract: A color toner composition for developing latent electrostatic images includes nanopowder-coated toner particles, the powder-coated toner particles being characterized in that each comprises a core toner particle having a volume average diameter, Dp, and the core toner particles have affixed to their surfaces a plurality of discrete colorant powder particles having a volume average diameter, dp, wherein the ratio of Dp/dp is at least about 5 and the weight fraction of colorant powder particles is at least about 0.01 based on the combined weight of core toner particles and colorant powder particles. Preferably, the weight fraction of colorant powder particles is from about 0.3 to about 3 times the product, (?p/?r) (d/r) (1+d/r)2, where ?p is the density of the colorant powder particles, ?r the density of the core resin particles, d, the volumetric mean diameter of the colorant powder particles and r the volumetric mean radius of the toner core resin particles.
    Type: Grant
    Filed: April 22, 2004
    Date of Patent: April 24, 2007
    Assignee: DPI Solutions, Incorporated
    Inventors: Chul-Hwan Kim, Kyung Hee Kim, Eui Joon Choi, Hyun-Nam Yoon