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:
Mar. 23, 1999
Filed:
Jan. 27, 1998
Applicant:
Inventors:
Assignee:
Toray Industries, Inc., , JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
549430 ; 549431 ; 568724 ;
Abstract
Cyclic formal is manufactured by cyclic reaction of an alkylene glycol and an aldehyde in a reactor, producing formal mixed with unreacted aldehyde as an impurity, which impurity is reduced in amount by connecting the reactor to a distillation tower and continuously supplying alkylene glycol to the distillation tower from which unreacted formaldehyde and a cyclic formal are being distilled, and continuously reacting them with supplied raw formaldehyde by countercurrent flow during distillation; water content in azeotropic admixture with cyclic formal can be removed by azeotropic distillation with a hydrocarbon azeotropic mixture with water, distilling water from the cyclic formal.