Patents by Inventor Kyung-Ju Choi

Kyung-Ju 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: 20240130230
    Abstract: The present disclosure relates to a plurality of host materials, organic electroluminescent compounds, and organic electroluminescent devices comprising the same. By comprising specific combinations of compounds according to the present disclosure as the plurality of host materials or by comprising a compound according to the present disclosure, it is possible to provide organic electroluminescent devices having improved lifespan characteristics compared to conventional organic electroluminescent devices.
    Type: Application
    Filed: August 8, 2023
    Publication date: April 18, 2024
    Inventors: Doo-Hyeon MOON, DaiKyu KIM, Hyo-Jung LEE, Yea-Mi SONG, Kyoung-Jin PARK, Hyun-Ju KANG, Ga-Won LEE, Mi-Ja LEE, Kyung-Hoon CHOI
  • Publication number: 20240090326
    Abstract: The present disclosure relates to an organic compound having the following structure, and an organic light emitting diode (OLED) and an organic light emitting device including the organic compound. The organic compound can be a bipolar compound having a p-type moiety and an n-type moiety and has high energy level and proper energy bandgap for an emissive layer of the OLED. As the organic compound is applied into the emissive layer, the OLED can maximize its luminous properties as holes and electrons are recombined uniformly over the whole area in an emitting material layer (EML).
    Type: Application
    Filed: September 26, 2023
    Publication date: March 14, 2024
    Applicants: LG DISPLAY CO., LTD, KOREA UNIVERSITY RESEARCH AND BUSINESS FOUNDATION
    Inventors: Kyung-Jin YOON, Dae-Wi YOON, Ji-Ae LEE, Su-Na CHOI, Dong-Hoon CHOI, Min-Ju CHO, JiWon YOON
  • Patent number: 11590443
    Abstract: A system and method for making electret media is presently provided. The method involves placing a piezoelectric material adjacent a media and applying a mechanical stress to the piezoelectric material and thereby transferring an electric charge from the piezoelectric material to the media and making the electret media. The system is configured to place the piezoelectric material adjacent the media and to apply mechanical stress to the piezoelectric material.
    Type: Grant
    Filed: August 2, 2019
    Date of Patent: February 28, 2023
    Assignee: Clean and Science Company, Ltd.
    Inventor: Kyung-Ju Choi
  • Publication number: 20210036216
    Abstract: A system and method for making electret media is presently provided. The method involves placing a piezoelectric material adjacent a media and applying a mechanical stress to the piezoelectric material and thereby transferring an electric charge from the piezoelectric material to the media and making the electret media. The system is configured to place the piezoelectric material adjacent the media and to apply mechanical stress to the piezoelectric material.
    Type: Application
    Filed: August 2, 2019
    Publication date: February 4, 2021
    Inventor: KYUNG-JU Choi
  • Patent number: 10617984
    Abstract: A tailored multilayered nano-fibrous filtration media having at least two adjacent layers of nano-fibrous media and a method for making is presently disclosed. The method comprises selecting an overall mean flow pore size for tailoring the multilayered nano-fibrous filtration media, choosing a first layers of nano-fibrous media, calculating an overall mean flow pore size (OMFP) of the tailored multilayered nano-fibrous filtration media, determining if the calculated OMFP is approximately equal to the selected OMFP, if not approximately equal then choosing a different number of layers chosen or choosing at least one layer having a porosity or mean flow pore size different than the previously chosen layer of nano-fibrous media, and adjacently layering each finally chosen layer of nano-fibrous media.
    Type: Grant
    Filed: April 17, 2015
    Date of Patent: April 14, 2020
    Assignee: Clean and Science Company, Ltd.
    Inventor: Kyung-Ju Choi
  • Patent number: 10272375
    Abstract: A fluid filter material configured to have a desirable efficiency at a low pressure drop is presently disclosed. The fluid filter material has a relatively open pleatable scrim comprised of a wet-laid or dry-laid material with natural and synthetic fibers. A layer of expanded polytetrafluoroethylene filaments have a first surface bonded with the pleatable scrim and the fluid filter material is pleatable and self-supporting. The natural fibers in the scrim may comprise cellulosic fibers, cotton, rayon, or other natural fibrous materials. The scrim may also comprise synthetic fibers.
    Type: Grant
    Filed: September 19, 2014
    Date of Patent: April 30, 2019
    Assignee: CLEAN AND SCIENCE COMPANY, LTD.
    Inventor: Kyung-Ju Choi
  • Publication number: 20180326361
    Abstract: Disclosed herein is filtration material having expanded polytetrafluoroethylene (ePTFE) and method of making. The method comprises expanding polytetrafluoroethylene in a machine direction orienter (MDO) and expanding or stretching to a ratio from about 20:1 up to about 100:1. The sheet of polytetrafluoroethylene is then relaxed. Upon relaxing the sheet of polytetrafluoroethylene, the sheet of polytetrafluoroethylene is fed into a transverse direction orienter (TDO). The temperature of the sheet of polytetrafluoroethylene in TDO is maintained to remain below 200° C. The sheet of polytetrafluoroethylene is then expanded or stretched to a ratio from about 1.5:1 up to about 100:1, with the TDO, thus providing the expanded polytetrafluoroethylene of the present disclosure having increased tensile strength and finer filaments.
    Type: Application
    Filed: February 8, 2016
    Publication date: November 15, 2018
    Inventor: KYUNG-JU CHOI
  • Publication number: 20180056220
    Abstract: A tailored multilayered nano-fibrous filtration media having at least two adjacent layers of nano-fibrous media and a method for making is presently disclosed. The method comprises selecting an overall mean flow pore size for tailoring the multilayered nano-fibrous filtration media, choosing a first layers of nano-fibrous media, calculating an overall mean flow pore size (OMFP) of the tailored multilayered nano-fibrous filtration media, determining if the calculated OMFP is approximately equal to the selected OMFP, if not approximately equal then choosing a different number of layers chosen or choosing at least one layer having a porosity or mean flow pore size different than the previously chosen layer of nano-fibrous media, and adjacently layering each finally chosen layer of nano-fibrous media.
    Type: Application
    Filed: April 17, 2015
    Publication date: March 1, 2018
    Inventor: KYUNG-JU CHOI
  • Publication number: 20170226675
    Abstract: A system and process for making a polymeric fibrous material having increased beta content is provided herein. The system is configured for meltblowing polymer into a fibrous material having high beta crystalline content and has an extruder for melting and moving a polymer to a meltblowing die. The meltblowing die has a longitudinally extending die tip with a plurality of spinnerets substantially equidistantly spaced from each other and a longitudinal fluid material flow through passage disposed along each longitudinal side of the die tip configured to axially attenuate the melted polymer from the die tip in fibrous form. A plurality of liquid spray nozzles are configured and disposed to spray a liquid into the fibrous melted polymer attenuated from the die tip.
    Type: Application
    Filed: August 17, 2016
    Publication date: August 10, 2017
    Inventor: KYUNG-JU CHOI
  • Patent number: 9587329
    Abstract: A system and process for making a polymeric fibrous material having increased beta content is provided herein. The system is configured for meltblowing polymer into a fibrous material having high beta crystalline content and has an extruder for melting and moving a polymer to a meltblowing die. The meltblowing die has a longitudinally extending die tip with a plurality of spinnerets substantially equidistantly spaced from each other and a longitudinal fluid material flow through passage disposed along each longitudinal side of the die tip configured to axially attenuate the melted polymer from the die tip in fibrous form. A plurality of liquid spray nozzles are configured and disposed to spray a liquid into the fibrous melted polymer attenuated from the die tip.
    Type: Grant
    Filed: December 11, 2013
    Date of Patent: March 7, 2017
    Inventor: Kyung-Ju Choi
  • Publication number: 20160082376
    Abstract: A fluid filter material configured to have a desirable efficiency at a low pressure drop is presently disclosed. The fluid filter material has a relatively open pleatable scrim comprised of a wet-laid or dry-laid material with natural and synthetic fibers. A layer of expanded polytetrafluoroethylene filaments have a first surface bonded with the pleatable scrim and the fluid filter material is pleatable and self-supporting. The natural fibers in the scrim may comprise cellulosic fibers, cotton, rayon, or other natural fibrous materials. The scrim may also comprise synthetic fibers.
    Type: Application
    Filed: September 19, 2014
    Publication date: March 24, 2016
    Inventor: KYUNG-JU CHOI
  • Publication number: 20150159301
    Abstract: A system and process for making a polymeric fibrous material having increased beta content is provided herein. The system is configured for meltblowing polymer into a fibrous material having high beta crystalline content and has an extruder for melting and moving a polymer to a meltblowing die. The meltblowing die has a longitudinally extending die tip with a plurality of spinnerets substantially equidistantly spaced from each other and a longitudinal fluid material flow through passage disposed along each longitudinal side of the die tip configured to axially attenuate the melted polymer from the die tip in fibrous form. A plurality of liquid spray nozzles are configured and disposed to spray a liquid into the fibrous melted polymer attenuated from the die tip.
    Type: Application
    Filed: December 11, 2013
    Publication date: June 11, 2015
    Inventor: KYUNG-JU CHOI
  • Publication number: 20140367325
    Abstract: This invention relates to a multi-stage stretching operation for production of expanded stretched porous polytetrafluoroethylene (ePTFE) fibrous materials with minimal node size and minimized filament sizes. A plurality of stretching or expansions may be implemented on the film including combinations of MDO and TDO stretches including at least two longitudinal stretches and at least one transverse stretch. Subsequent stretches occur at rates generally less than a prior similar longitudinal or transverse type of expansion.
    Type: Application
    Filed: June 12, 2009
    Publication date: December 18, 2014
    Inventors: Kyung-Ju Choi, Yoshiyuki Shibuya, Kunihiko Inui
  • Patent number: 8152889
    Abstract: A filter media product and method of making the same wherein the filter media is pleatable and has at least one support scrim comprised of a melt bonded non-woven material or a fuse bonded non-woven material bonded to a layer of expanded polytetrafluoroethylene. The filter media may have a single support scrim with one or more layers and optionally may have a support scrim on both an upstream and downstream surface where both or neither support scrim is multilayered. The filter media may have an efficiency greater than, equal to, or less than HEPA.
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: April 10, 2012
    Assignee: AAF-McQuay Inc.
    Inventor: Kyung-Ju Choi
  • Publication number: 20110232835
    Abstract: A filter media product and method of making the same wherein the filter media is pleatable and has at least one support scrim comprised of a melt bonded non-woven material or a fuse bonded non-woven material bonded to a layer of expanded polytetrafluoroethylene. The filter media may have a single support scrim with one or more layers and optionally may have a support scrim on both an upstream and downstream surface where both or neither support scrim is multilayered. The filter media may have an efficiency greater than, equal to, or less than HEPA.
    Type: Application
    Filed: June 10, 2011
    Publication date: September 29, 2011
    Inventor: Kyung-Ju Choi
  • Patent number: 7959705
    Abstract: A filter media product and method of making the same wherein the filter media is pleatable and has at least one support scrim comprised of a melt bonded non-woven material or a fuse bonded non-woven material bonded to a layer of expanded polytetrafluoroethylene. The filter media may have a single support scrim with one or more layers and optionally may have a support scrim on both an upstream and downstream surface where both or neither support scrim is multilayered. The filter media may have an efficiency greater than, equal to, or less than HEPA.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: June 14, 2011
    Assignee: AAF-McQuay Inc.
    Inventor: Kyung-Ju Choi
  • Publication number: 20110062077
    Abstract: A filter media product and method of making the same wherein the filter media is pleatable and has at least one support scrim comprised of a melt bonded non-woven material or a fuse bonded non-woven material bonded to a layer of expanded polytetrafluoroethylene. The filter media may have a single support scrim with one or more layers and optionally may have a support scrim on both an upstream and downstream surface where both or neither support scrim is multilayered. The filter media may have an efficiency greater than, equal to, or less than HEPA.
    Type: Application
    Filed: November 22, 2010
    Publication date: March 17, 2011
    Inventor: Kyung-Ju Choi
  • Patent number: 7896941
    Abstract: A filter media product and method of making the same wherein at least two filter media thicknesses of differing average coarse and fine fiber sizes are held in intertangled relationship forming a gradient density fibrous filter media with the fiber sizes having an overall average in successive thicknesses being either greater or less than the average fiber size of the intertangled fiber thickness(es).
    Type: Grant
    Filed: June 12, 2007
    Date of Patent: March 1, 2011
    Assignee: AAF-McQuay Inc.
    Inventor: Kyung-Ju Choi
  • Patent number: 7837756
    Abstract: A filter media product and method of making the same wherein the filter media is pleatable and has at least one support scrim comprised of a melt bonded non-woven material or a fuse bonded non-woven material bonded to a layer of expanded polytetrafluoroethylene. The filter media may have a single support scrim with one or more layers and optionally may have a support scrim on both an upstream and downstream surface where both or neither support scrim is multilayered. The filter media may have an efficiency greater than, equal to, or less than HEPA.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: November 23, 2010
    Assignee: AAF-McQuay Inc.
    Inventor: Kyung-Ju Choi
  • Patent number: 7661540
    Abstract: A unified pleated filter arrangement including a unified method and product wherein successive pleat flanks are spaced by communicably facing increments of spacing material with the pleat flanks being a selectively spaced and uniformly level geometric configuration.
    Type: Grant
    Filed: December 30, 2003
    Date of Patent: February 16, 2010
    Assignee: AAF McQuay, Inc.
    Inventor: Kyung-Ju Choi