Patents by Inventor Hwa Yeong CHOI

Hwa Yeong 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).

  • METHOD FOR PREPARING A CATHODE OF A SECONDARY BATTERY AND A PURIFIED N-METHYL PYRROLIDONE, AND PURIFYING A WASTE N-METHYL PYRROLIDONE USING AN INHIBITOR
    Publication number: 20240387829
    Abstract: In a method for preparing a cathode of a secondary battery, a method for preparing a purified N-methyl pyrrolidinone (NMP), and a method for purifying a waste NMP, an inhibitor is added to prevent NMP from being decomposed to produce formaldehyde during the process. 1. The inhibitor may be a phenol-based antioxidant and/or an amine-based light stabilizer.
    Type: Application
    Filed: May 16, 2024
    Publication date: November 21, 2024
    Inventors: JAE WON SHIM, SUNG WON SHIM, BYUNG KI SON, HWAN CHOI, YOUN SOO SHIN, TAE GI CHOI, HWA YEONG CHOI, YEONG SU CHOO
  • METHOD FOR PURIYFING WASTE N-METHYL-2-PYRROLIDONE
    Publication number: 20230192609
    Abstract: Provided is a method for purifying waste N-methyl-2-pyrrolidone, the method comprising the steps of: reacting the waste N-methyl-2-pyrrolidone containing an amine compound with an acid anhydride; converting the amine compound into an amide compound; and removing the amide compound by distillation, thereby manufacturing high-purity N-methyl-2-pyrrolidone that can be reused.
    Type: Application
    Filed: December 20, 2022
    Publication date: June 22, 2023
    Applicant: JAEWON INDUSTRIAL CO., LTD
    Inventors: Sung Won SHIM, Byung Ki SON, Hwan CHOI, Youn Soo SHIN, Hwa Yeong CHOI, Tae Gi CHOI, Yeong Su CHOO
  • METHOD FOR PURIFYING AN ALKYLENE GLYCOL MONOALKYL ETHER CARBOXYLIC ACID ESTER HAVING HIHG-PURITY USED IN PHOTO RESIST PROCESS
    Publication number: 20230095681
    Abstract: Provided is a method for purifying an alkylene glycol monoalkyl ether carboxylic acid ester (AGAECE) for photoresist processing, wherein the method comprises the step of distillation after passing industrial AGAECE through a porous adsorbent impregnated with a basic material, and it is possible to obtain a semiconductor-grade high-purity AGAECE maintaining a low acid value and high purity according to the present invention.
    Type: Application
    Filed: September 21, 2022
    Publication date: March 30, 2023
    Applicant: JAEWON INDUSTRIAL CO., LTD
    Inventors: Sung Won SHIM, Byung Ki SON, Hwan CHOI, Youn Soo SHIN, Hwa Yeong CHOI, Ho JEONG