Patents by Inventor Dong-hun Hyun

Dong-hun Hyun 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).

  • Micro needle roller assembly
    Patent number: 9987475
    Abstract: The present invention provides a micro needle roller assembly comprising a roller head including an external cylindrical member having a plurality of micro needles mounted on a surface thereof and an internal member placed in the external member and supported to the external member by supporting pieces; and a handling member coupled to the internal member for rotating the internal member of the roller head; the plurality of micro needles, the external cylindrical member and the internal member being made of a polymer resin.
    Type: Grant
    Filed: June 27, 2007
    Date of Patent: June 5, 2018
    Assignees: LOTTE CHEMICAL CORPORATION, KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Chang-hyun Kim, Dong-hun Hyun, Seung-sup Lee, Man-hee Han
  • Method for preparing polyamide resin
    Patent number: 9657138
    Abstract: The present invention relates to a method for preparing a polyamide resin, comprising the steps of: (a) preparing a polyamide polymer by anionically polymerizing a monomer including 2-pyrrolidone; (b) refining an unreacted monomer and a catalyst in the polyamide polymer with water; (c) pH-controlling through an ion exchange of the refined water; and (d) recovering the unreacted monomer by concentrating the pH-controlled water.
    Type: Grant
    Filed: December 3, 2014
    Date of Patent: May 23, 2017
    Assignee: GS CALTEX CORPORATION
    Inventors: Su-Jeong Lee, Dong-Hun Hyun, Hee-Jong Lee
  • METHOD FOR PREPARING POLYAMIDE RESIN
    Publication number: 20160297930
    Abstract: The present invention relates to a method for preparing a polyamide resin, comprising the steps of: (a) preparing a polyamide polymer by anionically polymerizing a monomer including 2-pyrrolidone; (b) refining an unreacted monomer and a catalyst in the polyamide polymer with water; (c) pH-controlling through an ion exchange of the refined water; and (d) recovering the unreacted monomer by concentrating the pH-controlled water.
    Type: Application
    Filed: December 3, 2014
    Publication date: October 13, 2016
    Inventors: Su-Jeong LEE, Dong-Hun HYUN, Hee-Jong LEE
  • MICRO NEEDLE ROLLER ASSEMBLY
    Publication number: 20090312691
    Abstract: The present invention provides a micro needle roller assembly comprising a roller head including an external cylindrical member having a plurality of micro needles mounted on a surface thereof and an internal member placed in the external member and supported to the external member by supporting piece; and a handling member coupled to the internal member for rotating the internal member of the roller head; the micro needles, the external cylindrical member and the internal member being made of polymer resin.
    Type: Application
    Filed: June 27, 2007
    Publication date: December 17, 2009
    Inventors: Chang-hyun Kim, Dong-hun Hyun, Seung-sup Lee, Man-hee Han