Patents by Inventor Hee Won Hwang

Hee Won Hwang 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: 8093376
    Abstract: The present invention relates to a process of preparing hydroxyalkyl cellulose derivatives having improved enzymatic resistance. In particular, the present invention relates to a process of preparing hydroxyalkyl cellulose derivatives by reacting cellulose and ethylene oxide in the presence of alkali metal hydroxide, wherein the reaction between cellulose and ethylene oxide is performed in the presence of isopropyl alcohol azeotropic solvent in a horizontally agitated reactor, wherein the ethylene oxide is supplied via two steps, thus resulting in a two-step reaction, and the amount of alkali metal hydroxide remaining after the first reaction is controlled, thereby enabling to provide hydroxyalkyl cellulose derivatives having improved enzymatic resistance and turbidity and to remarkably decrease the solvent usage to have economical and environmental advantages.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: January 10, 2012
    Assignee: Samsung Fine Chemicals Co., Ltd.
    Inventors: Seok Soo Kim, Jung Ho So, Il Yong Lee, Hee Won Hwang
  • Publication number: 20090299051
    Abstract: The present invention relates to a process of preparing hydroxyalkyl cellulose derivatives having improved enzymatic resistance. In particular, the present invention relates to a process of preparing hydroxyalkyl cellulose derivatives by reacting cellulose and ethylene oxide in the presence of alkali metal hydroxide, wherein the reaction between cellulose and ethylene oxide is performed in the presence of isopropyl alcohol azeotropic solvent in a horizontally agitated reactor, wherein the ethylene oxide is supplied via two steps, thus resulting in a two-step reaction, and the amount of alkali metal hydroxide remaining after the first reaction is controlled, thereby enabling to provide hydroxyalkyl cellulose derivatives having improved enzymatic resistance and turbidity and to remarkably decrease the solvent usage to have economical and environmental advantages.
    Type: Application
    Filed: December 17, 2004
    Publication date: December 3, 2009
    Applicant: SANSUNG FINE CHEMICALS CO., LTD.
    Inventors: Seok Soo Kim, Jung Ho So, Il Yong Lee, Hee Won Hwang
  • Publication number: 20080242852
    Abstract: The present invention relates to a method for preparing hydroxyalkylalkylcellulose with high yield, more particularly to a method for preparing hydroxyalkylalkylcellulose with high yield, with at least 60% of alkoxy and hydroxyalkoxy substituted, by treating finely ground pulp with an alkali metal hydroxide at room temperature, reacting it with an alkylene oxide and an alkyl halide, and then adding an alkali metal hydroxide and an alkyl halide thereto. The method of the present invention is highly economical and also environment-friendly because waste of the reactants can be greatly reduced.
    Type: Application
    Filed: December 30, 2005
    Publication date: October 2, 2008
    Inventors: Seok Soo Kim, Ung-Jin Kim, Il Yong Lee, Hee Won Hwang, Yong Sung Jang