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:
Nov. 23, 1982
Filed:
Dec. 24, 1981
Applicant:
Inventor:
John G Green, Baton Rouge, LA (US);
Assignee:
The Dow Chemical Company, Midland, MI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
2604 / ; 2604 / ; 2604 / ;
Abstract
A method of concentrating a solution of methylene diphenyl diisocyanate in diphenyl oxide, which includes cooling the solution until part of the solution crystallizes, thereby forming a solid phase having a lower concentration of the methylene diphenyl diisocyanate, and a liquid phase having a higher concentration of the methylene diphenyl diisocyanate than in the original solution, and then separating the solid and liquid phases. The method is particularly applicable to the concentration of solutions of 4,4'-methylene diphenyl diisocyanate in diphenyl oxide.