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. 03, 1992
Filed:
Sep. 07, 1990
Thomas Moest, Moorrege, DE;
Claus H Pich, Moorrege, DE;
Nordmark Arzneimittel GmbH, Uetersen, DE;
Abstract
A process for the manufacture of pellets which are composed of xanthine derivatives and are predominantly spherical, have a particle size in the range of 0.3 to 4 mm and have a bulk density above 0.5 g/cm.sup.3 by reacting the appropriate xanthine derivative with water or a water/alcohol mixture, entails anhydrous powdered xanthine derivative with an average particle size of from 20 to 200 .mu.m being suspended by stirring at from 40.degree. to 70.degree. C. in a nonsolvent which is immiscible with water and has a boiling point in the range from 60.degree. to 160.degree. C., then adding from 10 to 40% by weight, based on the anhydrous xanthine derivative, of water or a water/alcohol mixture and subsequently allowing to cool to room temperature at from 5.degree. to 20.degree. C. per hour, it being possible to reduce the stirring speed after agglomeration to about 1/3 to 2/3 of the original, and the pellets being separated from the liquid and dried, the pellets being used, possibly with a delayed release coating, as active compound in a drug.