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:
Sep. 08, 1992
Filed:
Jan. 23, 1991
Applicant:
Inventor:
Richard Won, Palo Alto, CA (US);
Assignee:
Advanced Polymer Systems, Inc., Redwood City, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08J / ;
U.S. Cl.
CPC ...
424 7831 ; 424 7802 ; 424 7808 ; 424 7831 ; 424484 ; 424489 ; 424501 ;
Abstract
Active substances intended for topical application are incorporated in novel formulations in which they are retained as impregnants inside the pores of porous solid particles or microspheres. The pores form a continuous network open to the exterior of the particles, permitting outward diffusion of the impregnants at a controlled rate depending on the pore size. The impregnated particles are prepared by impregnation of preformed particles with the active substance.