Patents by Inventor Sei-Jung Park

Sei-Jung Park 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: 10816712
    Abstract: The optical film according to the present invention uses polymethylmethacrylate that does not comprise cyclic monomers, but has excellent dimensional stability and optical properties, and thus, can be usefully used as a protection film of a polarization plate.
    Type: Grant
    Filed: May 29, 2017
    Date of Patent: October 27, 2020
    Assignee: LG Chem, Ltd.
    Inventors: Byoung Jun Mun, Joong Hoon Lee, Sung Ho Hwang, Sei Jung Park, Heon-Sik Song
  • Publication number: 20200172695
    Abstract: The present invention relates to a fluororesin porous film in which, based on the total thickness of the fluororesin porous film composed of a single 5 ?m to 300 ?m layer, a thickness ratio of nodes distributed on any one surface shows a difference of 5% or more compared to a thickness ratio of nodes distributed on the other surface forming the remaining part, a method for preparing the same, and a vent filter including the porous film.
    Type: Application
    Filed: August 9, 2018
    Publication date: June 4, 2020
    Applicant: LG CHEM, LTD.
    Inventors: Sei Jung PARK, Kyunghwan YOON, Byeong In AHN, Han Sol YOO
  • Patent number: 10633530
    Abstract: The resin composition for an optical material according to the present invention has features that it can implement a low retardation value during the preparation of an optical film, by using a polycarbonate composition satisfying a specific condition as a retardation-adjusting agent while using polymethyl methacrylate not containing a monomer having a cyclic structure at the main chain of the polymer.
    Type: Grant
    Filed: August 8, 2017
    Date of Patent: April 28, 2020
    Assignee: LG Chem, Ltd.
    Inventors: Joong Hoon Lee, Sei Jung Park, Sung Ho Hwang, Byoung Jun Mun, Heon-Sik Song
  • Publication number: 20190025489
    Abstract: The optical film according to the present invention uses polymethylmethacrylate that does not comprise cyclic monomers, but has excellent dimensional stability and optical properties, and thus, can be usefully used as a protection film of a polarization plate.
    Type: Application
    Filed: May 29, 2017
    Publication date: January 24, 2019
    Applicant: LG Chem, Ltd.
    Inventors: Byoung Jun Mun, Joong Hoon Lee, Sung Ho Hwang, Sei Jung Park, Heon-Sik Song
  • Publication number: 20180273742
    Abstract: The resin composition for an optical material according to the present invention has features that it can implement a low retardation value during the preparation of an optical film, by using a polycarbonate composition satisfying a specific condition as a retardation-adjusting agent while using polymethyl methacrylate not containing a monomer having a cyclic structure at the main chain of the polymer.
    Type: Application
    Filed: August 8, 2017
    Publication date: September 27, 2018
    Applicant: LG Chem, Ltd.
    Inventors: Joong Hoon Lee, Sei Jung Park, Sung Ho Hwang, Byoung Jun Mun, Heon-Sik Song
  • Patent number: 9804307
    Abstract: The present disclosure relates to a multilayer optical film including a first film layer formed of a thermoplastic acrylic resin composition including 0.01 to 2.0 parts by weight of a triazine-based ultraviolet absorber; a second film layer formed of a thermoplastic acrylic resin composition including 0.1 to 5.0 parts by weight of at least one ultraviolet absorber selected from a group consisting of a triazole-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, an oxanilide-based ultraviolet absorber and a cyanoacrylate-based ultraviolet absorber; and a third film layer formed of the thermoplastic acrylic resin composition including 0.01 to 2.0 parts by weight of the triazine-based ultraviolet absorber, with respect to 100 parts by weight of the thermoplastic acrylic resin composition, a method of manufacturing the same, and a polarizing plate including the same.
    Type: Grant
    Filed: June 17, 2014
    Date of Patent: October 31, 2017
    Assignee: LG Chem, Ltd.
    Inventors: Jun-Geun Um, Nam-Jeong Lee, Sang-Min Kwak, Suk-Il Youn, Sei-Jung Park
  • Publication number: 20160244593
    Abstract: There are provided a resin composition including a particulate thermoplastic acrylic resin and a triazine-based ultraviolet (UV) absorber, a preparation method thereof, and an optical film including the same.
    Type: Application
    Filed: June 17, 2014
    Publication date: August 25, 2016
    Inventors: Jun-Geun UM, Suk-Il YOUN, Nam-Jeong LEE, Sang-Min KWAK, Sei-Jung PARK
  • Publication number: 20160245970
    Abstract: The present invention relates to a copolymer resin composition formed by polymerizing an alkyl methacrylate-based monomer, a styrene-based monomer, a phenylmaleimide-based monomer and an alkyl acrylate-based monomer and to an optical film formed using the copolymer resin composition. The resin composition of the present invention may reduce odors which may be generated during the film extrusion and have a good thermal resistance and thermal stability.
    Type: Application
    Filed: September 29, 2014
    Publication date: August 25, 2016
    Inventors: Jun Geun UM, Sung II PARK, Seong Jang JEON, Nam Jeong LEE, Sei Jung PARK, Tae Sung PARK, Cheol Ho KIM, Eun Jin JEON
  • Patent number: 9304239
    Abstract: The present disclosure relates to a method for preparing a thin polarizer, and a thin polarizer prepared using the same, the method including forming a film laminate by attaching a non-stretched polyvinyl alcohol (PVA) film having a thickness of 10 to 60 ?m to at least one surface of a non-stretched base film, using attractive force therebetween; and stretching the film laminate such that the thickness of the PVA film is 10 ?m or less.
    Type: Grant
    Filed: November 14, 2013
    Date of Patent: April 5, 2016
    Assignee: LG CHEM, LTD.
    Inventors: Sung-Hyun Nam, Jun-Geun Um, Kyun-Il Rah, Jong-Hyun Jung, Hye-Min Yu, Nam-Jeong Lee, Sei-Jung Park
  • Publication number: 20160054490
    Abstract: The present disclosure relates to a multilayer optical film including a first film layer formed of a thermoplastic acrylic resin composition including 0.01 to 2.0 parts by weight of a triazine-based ultraviolet absorber; a second film layer formed of a thermoplastic acrylic resin composition including 0.1 to 5.0 parts by weight of at least one ultraviolet absorber selected from a group consisting of a triazole-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, an oxanilide-based ultraviolet absorber and a cyanoacrylate-based ultraviolet absorber; and a third film layer formed of the thermoplastic acrylic resin composition including 0.01 to 2.0 parts by weight of the triazine-based ultraviolet absorber, with respect to 100 parts by weight of the thermoplastic acrylic resin composition, a method of manufacturing the same, and a polarizing plate including the same.
    Type: Application
    Filed: June 17, 2014
    Publication date: February 25, 2016
    Inventors: Jun-Geun UM, Nam-Jeong LEE, Sang-Min KWAK, Suk-Il YOUN, Sei-Jung PARK
  • Publication number: 20150309234
    Abstract: The present disclosure relates to a method for preparing a thin polarizer, and a thin polarizer prepared using the same, the method including forming a film laminate by attaching a non-stretched polyvinyl alcohol (PVA) film having a thickness of 10 to 60 ?m to at least one surface of a non-stretched base film, using attractive force therebetween; and stretching the film laminate such that the thickness of the PVA film is 10 ?m or less.
    Type: Application
    Filed: November 14, 2013
    Publication date: October 29, 2015
    Inventors: Sung-Hyun NAM, Jun-Geun UM, Kyun-Il RAH, Jong-Hyun JUNG, Hye-Min YU, Nam-Jeong LEE, Sei-Jung PARK
  • Publication number: 20150022878
    Abstract: An optical film and a polarizing plate including the same are provided. The optical film includes an acrylic resin having a glass transition temperature of 120° C. or higher and including an alkyl (meth)acrylate-based repeating unit and a styrene-based repeating unit, and a UV absorbent having a 1% thermal decomposition temperature greater than or equal to a temperature 2.5 times that of the glass transition temperature of the acrylic resin.
    Type: Application
    Filed: February 21, 2014
    Publication date: January 22, 2015
    Inventors: Suk-Il Youn, Sang-Min Kwak, Jun-Geun Um, Sei-Jung Park, Nam-Jeong Lee, Joon-Hoon Lee