US 12,454,505 B2
Method for purifying an alkylene glycol monoalkyl ether carboxylic acid ester having high-purity used in photo resist process
Sung Won Shim, Yeosu-si (KR); Byung Ki Son, Daejeon (KR); Hwan Choi, Yeosu-si (KR); Youn Soo Shin, Yeosu-si (KR); Hwa Yeong Choi, Yeosu-si (KR); and Ho Jeong, Jeollanam-do (KR)
Assigned to JAEWON INDUSTRIAL CO., LTD, Yeosu-si (KR)
Filed by JAEWON INDUSTRIAL CO., LTD, Yeosu-si (KR)
Filed on Sep. 21, 2022, as Appl. No. 17/934,099.
Claims priority of application No. 10-2021-0127311 (KR), filed on Sep. 27, 2021.
Prior Publication US 2023/0095681 A1, Mar. 30, 2023
Int. Cl. C07C 67/56 (2006.01); C07C 67/54 (2006.01); G03F 7/16 (2006.01)
CPC C07C 67/56 (2013.01) [C07C 67/54 (2013.01); G03F 7/161 (2013.01)] 10 Claims
 
1. A method of purifying an alkylene glycol monoalkyl ether carboxylic acid ester for photoresist process, comprising the steps of:
impregnating a porous adsorbent with a basic material;
lowering the acidity by passing an alkylene glycol monoalkyl ether carboxylic acid ester (AGAECE) as a raw material through the porous adsorbent impregnated with a basic material; and
distilling the AGAECE that has passed through the porous adsorbent,
wherein the AGAECE is represented by Formula 1, and an antioxidant is added in the distillation step:

OG Complex Work Unit Chemistry
wherein R1 is hydrogen or a C1-C8alkyl group, R2 and R3 are each independently hydrogen or a C1-C11 alkyl group, and n is an integer of 1 to 11, provided that when n is an integer of 2 or more, each R2 is the same as or different from each other.