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. 11, 1980
Filed:
Sep. 28, 1979
Koichiro Ohtomo, Takatsuki, JP;
Yukio Horikawa, Matsubara, JP;
Kanebo, Ltd., Tokyo, JP;
Kanebo Spun Silk, Ltd., Nagano, JP;
Abstract
Finely powdered high-purity fibroin and a process for producing the same are disclosed. The fibroin is a fine powder of fibroin in nonfibrous and particulate form which has an average molecular weight of not less than 50,000, particle diameters of from 1 to 100.mu., and a bulk density of from 0.1 to 0.7 g/cm.sup.3 as measured in the dry state and which contains at least 50% by weight of hot-water-insoluble fibroin having the .beta.-configuration. The process comprises dissolving a degummed silk material in an aqueous salt solution containing from 5 to 80% by weight of an alkali metal salt or alkaline earth metal salt; dialyzing the resulting aqueous fibroin solution; adding from 1 to 150 parts by weight of an alcohol to 100 parts by weight of the dialyzed aqueous fibroin solution having a fibroin concentration of from 3 to 20% by weight to form a gel of fibroin; dehydrating and drying the gel so formed; and then pulverizing the resulting powder. The fine powder of fibroin thus obtained is useful as an additive for cosmetic and pharmaceutical preparations.