The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 23, 2026
Filed:
Jun. 18, 2021
Maruzen Petrochemical Co., Ltd., Tokyo, JP;
Yuma Hakoda, Ichihara, JP;
Ryo Fujisawa, Ichihara, JP;
Kazuhiko Haba, Ichihara, JP;
Daisuke Tabata, Ichihara, JP;
Yoshiyuki Furuya, Ichihara, JP;
Ryo Sato, Ichihara, JP;
Tomo Oikawa, Ichihara, JP;
Maruzen Petrochemical Co., Ltd., Tokyo, JP;
Abstract
Provided are a 4-hydroxystyrene solution with high purity and good storage stability that is suitable as a source for producing a 4-hydroxystyrene polymer on a commercial scale, and a method of producing the solution. The method of producing a 4-hydroxystyrene solution of the present invention includes the following steps (i) to (iv):(i) deprotection step for contacting 4-acetoxystyrene with a base in a solvent to produce 4-hydroxystyrene; (ii) neutralization step for adding an acid to the solution containing 4-hydroxystyrene after deprotection to neutralize the solution; (iii) step for washing the solution containing 4-hydroxystyrene after neutralization with water; and (iv) solvent replacement step for adding a solvent that can dissolve 4-hydroxystyrene to the solution containing 4-hydroxystyrene followed by distillation at 40° C. or lower to remove other components than 4-hydroxystyrene and excess solvent.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile