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:
May. 05, 1992
Filed:
Oct. 26, 1990
William A Welsh, Highland, MD (US);
Stephen R Schmidt, Silver Spring, MD (US);
W. R. Grace & Co.-Conn., New York, NY (US);
Abstract
An improved flatting agent comprising an inorganic hydrogel having a pore volume of at least 1.0 ml/g, an average particle size in the range 1 to 10 microns, and a particle size distribution such thatt when the flatting agent is dispersed in a coating, the fineness of grind is at least 4.75 on the Hegman scale. The inorganic hydrogel flatting agents of this invention are prepared by milling an inorganic hydrogel under controlled temperature conditions wherein a volatiles content of at least 40 weight percnet is maintained, to produce inorganic hydrogel particles characterized by a pore volume of at least 1.0 ml/g, an average particle size in the range of 1 to 10 microns, and a particle size distribution such that when the flatting agent is dispersed in a coating, the fineness of grind is at least 4.75 on the Hegman scale. Also provided in accordance witth this invention are improved coating compositions comprising a full gloss coating containing the above described flatting agents dispersed in the full gloss coating in from 3 to 15 weight percent loading on a solids basis.