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. 16, 1993
Filed:
Jun. 22, 1990
Applicant:
Inventors:
Robert E Sparks, Kirkwood, MO (US);
Norbert S Mason, St. Louis, MO (US);
Pierre Autant, Commentry, FR;
Andre Cartillier, Commentry, FR;
Raymond Pigeon, Francheville, FR;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
A61K / ;
U.S. Cl.
CPC ...
424438 ; 424475 ; 424490 ; 424491 ; 424493 ; 424494 ; 424497 ; 424498 ;
Abstract
A composition which is stable in a medium in which the pH is greater than or equal to 5.5 and which permits the release of an active substance in a medium in which the pH is less than or equal to 3.5, comprising the active substance, which contains inclusions of, or which is completely or partially covered by, a pH sensitive material whose extent and/or rate of swelling is greater in an acidic medium than in a neutral medium, and a coating of a hydrophobic layer.