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:
Feb. 20, 1979
Filed:
Oct. 25, 1977
Applicant:
Inventors:
Assignee:
Toray Industries, Inc., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
2602 / ;
Abstract
Purified .alpha.-amino-.epsilon.-caprolactam free from not only visible ray-absorbing substances but ultra-violet ray-absorbing substances, such as, tetrahydrophenazine and octahydrophenazine, and volatile basic substances such as, ammonium salts, is obtained by dissolving a crude .alpha.-amino-.epsilon.-caprolactam in a solvent consisting of at least one alkyl ester of saturated aliphatic acid of the formula: