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:
Jan. 17, 1978
Filed:
Jul. 12, 1976
Tsuneo Tsubakimoto, Toyonaka, JA;
Iwao Fuzikawa, Toyonaka, JA;
Katsumi Uchida, Shimamoto, JA;
Osamu Minamidani, Higashiosaka, JA;
Nippon Shokubai Kagaku Kogyo Co. Ltd., Osaka, JA;
Abstract
A process for producing a dyed finely divided hardened resin of uniform particle size excelling in dispersibility which comprises, in combination, the steps of reacting benzoguanamine with formaldehyde in a ratio of 1.0 mole of the former to 1.2 - 3.5 moles of the latter in an aqueous medium at a pH ranging between 5 and 10 to prepare an aqueous liquid of a soluble and fusible resin having a degree of modified water tolerance of 0-150%, preparing an aqueous emulsion of a dyed soluble and fusible resin by using said aqueous liquid, a dye and a protective colloid, adding to the thus prepared aqueous emulsion in a ratio of 1 - 15 parts by weight per 100 parts by weight of the soluble and fusible resin of ultramicroscopic silica of a specific surface area as measured by the Brunauer, Emmett and Teller Method in the range of about 50 m.sup.2 /g to about 400 m.sup.2 /g and a particle size in the range of about 0.005 to about 0.05 micron, adding a curing catalyst, holding the aqueous emulsion for at least one hour at a temperature in the range of 40.degree.-60.degree. C., heating the aqueous emulsion at a temperature in the range of 60.degree.-200.degree. C. at normal atmospheric or superatmospheric pressure to harden the resin thereby preparing a suspension of a dyed finely divided hardened resin, and thereafter separating the hardened resin from the suspension followed by drying and de-aggregating the dried hardened resin.