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:
Oct. 16, 1984
Filed:
Nov. 09, 1982
Jozsef Matyasi, Almasfuzito-felso, HU;
Gyorgy Kaptay, Almasfuzito-felso, HU;
Laszlo Zsembery, Almasfuzito-felso, HU;
Bela Kokeny, Komarom, HU;
Jozsef T Toth, Almasfuzito-felso, HU;
Maria Toth Nee Homostrei, Almasfuzito-felso, HU;
Imre Penzes, Almasfuzito-felso, HU;
Magyar Aluminiumipari Troeszt, Budapest, HU;
Abstract
Process for the preparation of alkali-poor .alpha.-alumina for ceramic purposes. Technical grade aluminum hydroxide is activated and calcinated in the presence of a mineralizing mixture comprising halides and boron compounds. The process further comprises activating aluminum hydroxide at a temperature of 500-600 degrees C., washing the activated product with alkali-free water containing calcium ions and having a conductivity not exceeding 70 .mu.S/cm until the alkali content expressed in Na.sub.2 O becomes lower than 0.15% by weight, adding 0.4-0.7% by weight of a mineralizing mixture to the washed product, and calcinating the same at a temperature of 1200-1350 degrees C.