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:
Jul. 21, 1987
Filed:
Mar. 14, 1985
Jakob Rademachers, Krefeld, DE;
Karlheinz Turban, Krefeld, DE;
Gerhard Franz, Krefeld, DE;
Werner Fuhr, Krefeld, DE;
Bernd Holle, Krefeld, DE;
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
A process for the production of an anisometric yellow-brown zinc ferrite pigment comprising homogeneously mixing zinc oxide having a specific BET surface of more than 2 m.sup.2 /g with needle-shaped .alpha.-FeOOH obtained from an iron salt solution by mixing with alkali and subsequently oxidizing in a nucleation and pigment growth stage, the FeOOH having a specific BET surface of about 15 to 25 m.sup.2 /g, an average needle width of about 0.025 to 0.125 .mu.m and an average needle length of about 0.2 to 0.6 .mu.m, annealing the mixture at a temperature of about 700.degree. to 1000.degree. C., cooling and grinding.