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. 14, 2009
Filed:
Jun. 19, 2008
Shuhei Yamada, Ube, JP;
Atsushi Ryokawa, Ube, JP;
Shuhei Yamada, Ube, JP;
Atsushi Ryokawa, Ube, JP;
Central Glass Company, Limited, Ube-shi, JP;
Abstract
Disclosed are first to sixth processes for respectively producing hafnium tetra-tertiary-butoxide, tetrakis(acetylacetonato)hafnium, tetrakis(1-methoxy-2-methyl-2-propanolato)hafnium, hafnium tetra-tertiary-amyloxide, tetrakis(3-methyl-3-pentoxy)hafnium, and tetrakis(hexafluoroacetylacetonato)hafnium. The first process includes the steps of (a) adding a compound A(OXORf)(e.g., CFSOH) to a crude hafnium amide Hf[N(R)(R)]; (b) subjecting a product of the step (a) to a distillation under reduced pressure; (c) adding a lithium alkylamide Li(NRR) to a fraction obtained by the step (b); (d) subjecting a product of the step (c) to a distillation under reduced pressure; (e) adding tertiary butanol to a fraction obtained by the step (d); and (f) subjecting a product of the step (e) to a distillation under reduced pressure. The tertiary butanol of the step (e) is replaced with acetylacetone, 1-methoxy-2-methyl-2-propanol, tertiary amyl alcohol, 3-methyl-3-pentanol, and hexafluoroacetylacetone in the second to six processes, respectively.