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:
Apr. 27, 1993
Filed:
Mar. 12, 1992
Akos Kiss, Alzenau-Wasserlos, DE;
Dietrich Speer, Hanau, DE;
Peter Kleinschmit, Hanau, DE;
Jenny Horst, Gelnhausen, DE;
Degussa Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
Gray-black inclusion pigments are made using zirconium silicate as the encasing substance and carbon black particles as the inclusion phase by annealing a mixture of zirconium dioxide, a source for silicon dioxide, carbon black and mineralizers under reducing conditions at 900.degree.-1400.degree. C. The process uses zeolites with an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of more than 4, preferably more than 10, as the SiO.sub.2 source. The depth of the color can be increased by also using an adhesion agent, especially silicon oil. The use of the zeolites facilities the employment of different zirconium dioxide qualities and permits the production of pigments with higher carbon black inclusion rates.