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:
Oct. 10, 2000
Filed:
Jul. 10, 1998
Edwin Lee Johnson, Issaquah, WA (US);
Everett Junior Nichols, Edmonds, WA (US);
Vanson, Inc., Redmond, WA (US);
Abstract
The present invention provides novel methods of producing chitosan having a tap density of at least about 0.4 g/ml. In one aspect of the present invention, chitosan is selected having an average molecular mass of from about one thousand Daltons to about two million Daltons; a particle size that is smaller than 20 mesh; a viscosity of at least about 1 cps, and a percentage of deacetylation of from about 65% to about 98% A measured amount of the selected chitosan is then mixed with an amount of water that is from about two to about ten times the weight of the chitosan, and an amount of an acid that is at least about 0.1% of the weight of the chitosan. The acid is preferably an organic acid. The mixture of chitosan, water and acid is then mixed to a smooth paste, dried to a moisture content of from 0% moisture to about 20% moisture, and the particle size is preferably reduced to smaller than 20 mesh. In another aspect of the invention, chitosan is provided having a tap density of at least about 0.4 g/ml and the ability to freely flow through an orifice having a circular cross section having a diameter of about 4 mm. The chitosan of the present invention is relatively odorless.