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:
Jan. 24, 1978
Filed:
Jun. 16, 1976
Applicant:
Inventors:
Assignee:
Central Glass Company, Limited, Ube, JA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C01F / ; C01C / ; C01C / ;
U.S. Cl.
CPC ...
423489 ; 423356 ; 423472 ;
Abstract
Ammonium tetrafluoroaluminate particles having an average particle size above 50.mu. are reacted with an aluminum compound such as aluminum hydroxide or oxide first at a temperature of 250.degree. C to 300.degree. C and then at a temperature of 350.degree. to 500.degree. C to form crystalline particles of anhydrous aluminum fluoride (II) with an average particle size almost corresponding to the starting ammonium tetrafluoroaluminate. The heating of the crystalline particles to a temperature above 550.degree. C results in formation of aluminum fluoride (I) with a large average particle size.