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:
Dec. 19, 1989
Filed:
Dec. 08, 1987
Thomas L Steiner, Charlotte, NC (US);
Dana T Minnick, University Heights, OH (US);
Kenneth A Domeshek, Matthews, NC (US);
Donald H Lester, Jr, Pineville, NC (US);
Celanese Fibers, Inc., New York, NY (US);
Abstract
Microparticle of cellulose acetate and derivatives thereof characterized by being water soluble, having a large interior void space and having a plurality of open exterior surface pores. These water soluble microparticles can be loaded with a chemical selected from the group consisting of pharmaceuticals, dyes, flavorings, agriculturals, solid catalysts and fragrances. The microparticles are produced by forming spherical droplets of a dope of water soluble cellulose acetate and water soluble derivatives of cellulose acetate with a solvent therefor, precipitating the spherical droplets in a bath of a precipitant for water soluble cellulose acetate and water soluble derivatives of cellulose acetate, separating the excess precipitant from the microparticles, enriching the microparticles with the precipitant by contacting the microparticles one or more times with a solution of the precipitant, removing rapidly under vacuum substantially all of the precipitant from the microparticles, and recovering the resulting water soluble microparticles.