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:
Oct. 14, 2025
Filed:
Nov. 30, 2022
Nan Ya Plastics Corporation, Taipei, TW;
NAN YA PLASTICS CORPORATION, Taipei, TW;
Abstract
A method for producing a polyester polyol is provided, which includes: feeding a first antioxidant and a raw material reactant that includes a polyacid and a polyol into a reactor; subjecting the polyacid and the polyol to an esterification reaction to form an oligomer; and performing a prepolymerization reaction on the oligomer to obtain a prepolymerization reactant. During the prepolymerization reaction, the method includes sampling and monitoring an acid value of the prepolymerization reactant. When the acid value of the prepolymerization reactant reaches a first acid value, an esterification reaction catalyst is added to the prepolymerization reactant for carrying out a polycondensation reaction and generating a polycondensation reactant that contains the polyester polyol. During the polycondensation reaction, the method includes sampling and monitoring an acid value of the polycondensation reactant. When the acid value of the polycondensation reactant reaches a second acid value, the polycondensation reaction is terminated.