Patents by Inventor Sung-Ho Chun

Sung-Ho Chun 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: 7312285
    Abstract: The present invention relates to a method for preparing a cyclic olefin polymer by addition polymerization, and more particularly to a method for preparing a norbornene-based addition polymer, which comprises a step of contacting a norbornene-based monomer having an ester or acetyl group with a catalyst system comprising: a Group X transition metal compound; a compound comprising a neutral Group XV electron donor ligand having a cone angle of at least 160°; and a salt capable of offering an anion that can be weakly coordinated to the transition metal, in solvent. The norbornene-based addition polymer having an ester or acetyl group according to the present invention is transparent, has superior adhesivity and a low dielectric constant, and it generates no byproducts when attached to metal. Therefore, it can be used as an optical film, a retardation film, a protection film for a polarizer, POFs (plastic optical fiber), PCBs (printed circuit board), or insulators of electronic devices.
    Type: Grant
    Filed: July 7, 2003
    Date of Patent: December 25, 2007
    Assignee: LG Chem, Ltd.
    Inventors: Sung-Ho Chun, Won-Kook Kim, Sung-Cheol Yoon, Tae-Sun Lim, Heon Kim, Kyoung-Hoon Kim
  • Publication number: 20070021576
    Abstract: Disclosed is a method for preparing a cycloolefin polymer containing polar functional groups, comprising the steps of: a) preparing a catalyst mixture including i) a precatalyst; ii) a first cocatalyst; and iii) a second cocatalyst; and b) subjecting a monomer solution comprising a norbornene-based compound containing a polar functional group to an addition polymerization reaction in the presence of an organic solvent and the catalyst mixture, wherein the product yield of the prepared polymer is 50% by weight or more based on the total weight of the monomer.
    Type: Application
    Filed: July 20, 2006
    Publication date: January 25, 2007
    Inventors: Sung-Cheol Yoon, Sung-Ho Chun, Won-Kook Kim, Tae-Sun Lim, Heon Kim, Jung-Min Lee
  • Publication number: 20060050388
    Abstract: The present invention relates to a unified polarizing plate, which employs, as a protection layer of a polarizing film, a transparent film that can simultaneously function as a negative C-plate and transparent protection layer of a polarizing film and has negative refractive index toward thickness direction, thereby simultaneously performing functions as a negative C-plate for optical compensation and as a polarizing plate, and a method for preparing the same. The unified polarizing plate has superior durability at high temperature and high humidity compared to those employing TAC as a protection layer, and improves wide view angle of liquid crystal display having positive refractive index toward thickness direction, when the liquid crystal display device is ON or OFF.
    Type: Application
    Filed: February 6, 2004
    Publication date: March 9, 2006
    Inventors: Won-Kook Kim, Sung-Ho Chun, Sung-Cheol Yoon, Tae-Sun Lim, Heon Kim, Jung-Min Lee, Jeong-Su Yu, In-Seok Hwang, Beom-Seok Kim
  • Publication number: 20050190326
    Abstract: Provided are a vertically aligned liquid crystal display (VA-LCD) with good viewing angle characteristics, which has liquid crystals with negative dielectric anisotropy (??<0). In the VA-LCD, a polynorbornene based polymer film is used as a protection film and/or as a negative C-plate retardation film for an upper polarization plate and/or a lower polarization plate. Therefore, high contrast characteristics for a front view and an oblique angle view are realized and color change for an oblique angle view can be minimized.
    Type: Application
    Filed: January 7, 2005
    Publication date: September 1, 2005
    Applicant: LG Chem, Ltd.
    Inventors: Byoung-kun Jeon, Jeong-su Yu, Sergey Belyaev, Won-kook Kim, Sung-ho Chun, Sung-cheol Yoon, Tae-sun Lim, Heon Kim, Jung-min Lee
  • Publication number: 20050085606
    Abstract: Disclosed is a method for preparing a cycloolefin polymer containing polar functional groups, comprising: preparing a catalyst mixture including i) a precatalyst, containing a Group 10 transition metal having a ligand containing oxygen ions bonded to the metal; ii) a first cocatalyst which is an organic compound containing a Group 15 element; and iii) a second cocatalyst which is capable of providing an anion and weakly coordinating to the metal of the precatalyst; and subjecting a monomer solution comprising a norbornene-based compound containing a polar functional group to an addition polymerization reaction in the presence of an organic solvent and the catalyst mixture, at a temperature of 80-200° C., the total amount of the organic solvent being 50-800% by weight based on the total weight of the monomer contained in the monomer solution, and the product yield of the polymer being 50% by weight or more based on the total weight of the monomer.
    Type: Application
    Filed: December 3, 2003
    Publication date: April 21, 2005
    Applicant: LG CHEM, LTD
    Inventors: Sung-Cheol Yoon, Sung-Ho Chun, Won-Kook Kim, Tae-Sun Lim, Heon Kim, Jung-Min Lee
  • Publication number: 20050014913
    Abstract: The present invention provides a negative C-plate type optical anisotropic film having negative birefringence along the thickness direction. In particular, the present invention provides n film comprising cycloolefin addition polymer, which is prepared by addition polymerizing norbornene-based monomers, a method for preparing the same, and a liquid crystal display comprising the same. The film of the present invention can be used for optical compensation films of a variety of LCD (liquid crystal display) modes because the refractive index alone the thickness direction can be controlled by the kind and amount of functional groups introduced to the cycloolefin addition polymer.
    Type: Application
    Filed: November 19, 2003
    Publication date: January 20, 2005
    Inventors: Won-Kook Kim, Sung-Ho Chun, Sung-Cheol Yoon, Tae-Sun Lim, Heon Kim, Jung-Min Lee, Jeong-Su Yu
  • Publication number: 20050010006
    Abstract: The present invention relates to a norbornene based addition polymer, and more particularly to an addition polymer of norbornene based monomers containing an ester group. The present invention provides a norbornene-ester based addition polymer having a molecular weight (Mn) larger than 20,000 and comprising a norbornene-ester based monomer comprising more than 50 mol % of exo norbornene-ester monomer as a repeating unit, a method for preparing the same, and an optically anisotropic film comprising the same. The norbornene-ester based addition polymer of the present invention is transparent, has a low dielectric constant, has good thermal stability and strength, leaves no unwanted materials when attached to metals or other polymers, and has good adhesivity, so that it can be used for optical films, retardation films, plastic substrate materials, transparent polymers such as POF or PCB, insulating materials, or insulating electronic devices such as PCB or insulating materials.
    Type: Application
    Filed: July 7, 2003
    Publication date: January 13, 2005
    Inventors: Sung-Ho Chun, Won-Kook Kim, Sung-Cheol Yoon, Tae-Sun Lim, Heon Kim, Kyung-Hoon Kim, Jung-Min Lee, Kyung-Lim Paik, Sang-Doo Ahn
  • Publication number: 20040254318
    Abstract: The present invention relates to a method for preparing a cyclic olefin polymer by addition polymerization, and more particularly to a method for preparing a norbornene-based addition polymer, which comprises a step of contacting a norbornene-based monomer having an ester or acctyl group with a catalyst system comprising: a Group X transition metal compound; a compound comprising a neutral Group XV electron donor ligand having a cone angle of at least 160°; and a salt capable of offering an anion that can be weakly coordinated to the transition metal, in solvent. The norbornene-based addition polymer having an ester or acetyl group according to the present invention is transparent, has superior adhesivity and a low dielectric constant, and it generates no byproducts when attached to metal. Therefore, it can be used as an optical film, a retardation film, a protection film for a polarizer POFs (plastic optical fiber), PCBs (printed circuit board), or insulators of electronic devices.
    Type: Application
    Filed: May 7, 2004
    Publication date: December 16, 2004
    Inventors: Sung-Ho Chun, Won-Kook Kim, Sung-Cheol Yoon, Tae-Sun Lim, Heon Kim, Kyoung-Hoon Kim