Title:
【発明の名称】低分散率で所望のごとく調節された晶子サイズの▲か▼焼アルミナ製造
Document Type and Number:
Japanese Patent JP2001503368
Kind Code:
A
Abstract:
The invention concerns a process for the production of alumina for ceramics by calcining alumina trihydrate in the presence of a mineralizer such as a halogenated compound and/or a boron compound, the calcined alumina being constituted by friable agglomerates of elementary particles, or crystallites, of alpha alumina, the average size of which can be fixed as required, with a unimodal narrow distribution of crystallite sizes, characterized in that calcining of the alumina trihydrate is carried out in an industrial kiln in a renewed oxidising atmosphere at a temperature in the range 800 DEG C. to 1300 DEG C. for a period of 0.5 hour to 4 hours in the simultaneous presence of a halogenated compound acting as a mineralizer and a silica based alumina recrystallisation modifier which is uniformly and intimately distributed in the alumina trihydrate charge.
Inventors:
Deville, Jean
Ramlan, Jean-Michel
Ramlan, Jean-Michel
Application Number:
JP52109698A
Publication Date:
March 13, 2001
Filing Date:
November 03, 1997
Export Citation:
Assignee:
Aluminum Pescine
International Classes:
C04B35/111; C09K3/14; C01F7/442; (IPC1-7): C01F7/44
Attorney, Agent or Firm:
Keiichi Ota