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. 16, 1980
Filed:
Mar. 31, 1978
Kanzaki Paper Mfg. Co., Ltd., Tokyo, JP;
Abstract
The method of making oil-containing microcapsules comprises the step of (1) preparing an aqueous system comprising an aqueous solution of gelatin and at least one anionic colloid material and oil droplets dispersed in said solution (2) causing coacervation in said aqueous system at a temperature above the gelation point of said gelatin to form a coacervate suspension in which each of said oil droplets is surrounded by a coacervate and (3) cooling said coacervate suspension to a temperature below the gelation points of said gelatin to form multi-nucleus capsules. During the step of cooling the coacervate suspension, aggregation of particles of oil droplets each having a coacervate therearound is controlled by an agitation flow so as to allow formation of multi-nucleus microcapsules having an average diameter within the range of 3 to 20 microns. The gelatin has an average viscosity not larger than 35 millipoise in terms of the value measured by the bloom type pipette method at 40.degree..+-.0.5.degree. C. according to Japan Industrial Standard K 6503 with respect to a 62/3% aqueous solution of said gelatin at the pH of 4.5 and at least 5% by weight of said gelatin has a viscosity not larger than 25 millipoise in said terms and/or the anionic colloid material is a carboxymethylcellulose having a viscosity within the range of 2 to 500 centipoise measured by the Brookfield viscometer with a 60 r.p.m. No. 1 rotor with respect to a 2% aqueous solution of said carboxymethylcellulose at 25.degree. C.