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:
Jun. 14, 1983
Filed:
Mar. 15, 1982
Applicant:
Inventors:
Assignee:
Canadian Patents & Development Limited, Ottawa, CA;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C07J / ; C07J / ;
U.S. Cl.
CPC ...
2603972 ;
Abstract
A method of upgrading a product containing a minor proportion of pre-vitamin d.sub.2 or pre-vitamin d.sub.3 and a major proportion of tachysterol comprising irradiating the product with laser light in the wavelength range 330-360 nanometers to obtain a product containing approximately 95% pre-vitamin -D.sub.2 or pre-vitamin -D.sub.3, and heating this product to convert the pre-vitamin -D.sub.2 or pre-vitamin -D.sub.3 to vitamin -D.sub.2 or vitamin -D.sub.3.