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. 05, 2002
Filed:
May. 16, 2001
Applicant:
Inventors:
Shiao-Jung Chu, Hsinchu, TW;
Chien-Liang Hwang, Hsinchu, TW;
Assignee:
Chinese Petroleum Corp., , TW;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
C07D / ; C07D / ;
Abstract
A purification method for obtaining high-purity PMDA. The method controls temperatures of cyclone separators in a series to separate PMDA and other by-products of different sublimation temperatures. High-purity PMDA is collected in the first cyclone separator, and no other purification steps are needed.