EP0250085A2
Expired / Lapsed
EP
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Mono-size powders of barium titanate and method for their production
Assignee: Corning Glass Works
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Filing: 1987-05-13
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Granted: —
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Expires: 2007-05-13
Abstract
Abstract Mono-sized barium titanate powders which have high density and substantially pure stoichiometry are provided. The powders can be produced by reacting barium hydroxide with titanium dioxide in a protic solvent at a temperature of at least 100°C for a period of at least 48 hours, or by reacting barium hydroxide with a titanium alkoxide in a protic solvent at a temperature of about the boiling point of the alkyl alcohol corresponding to the alkoxide for a period of at least about 240 hours.
Inventors
- 👤 Edward Lilley
- 👤 Raja Rao Wusirika
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 03:39
CPC Classifications
C; C01; C01G; C01G23/00; B; B82; B82Y; B82Y30/00; C01G23/003; C01G23/006; C04; C04B; C04B35/00; C04B35/01; C04B35/46; C01P; C01P2004/00; C01P2004/30; C01P2004/32; C01P2004/51; C01P2004/52; C01P2004/60; C01P2004/62; C01P2004/64; C01P2006/00; C01P2006/10; C01P2006/12
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
45 words
A finely divided powder of BaTiO₃ having a Ba/Ti molar ratio of about 0.99-1.02 and a density of at least 5.7 g/cc prior to calcining, said powder having a mean primary particle size of about 0.09-0.2 micron with a geometric standard deviation of about 30%.
Claim 2
Dependent Claim
45 words
A finely divided powder of BaTiO₃ having a Ba/Ti molar ratio of about 0.99-1.02 and a density of at least 5.7 g/cc prior to calcining, said powder having a mean primary particle size of about 0.09-0.2 micron with a geometric standard deviation of about 30%.
Claim 3
Dependent Claim
14 words
The BaTiO₃ powder of claim 1 having a surface area of about 6-15 m²/g.
Claim 4
Dependent Claim
22 words
The BaTiO₃ powder of claim 1 wherein the BaTiO₃ has a density of 5.80-5.85 g/cc and a Ba/Ti molar ratio of 1.0-1.01.
Claim 5
Dependent Claim
23 words
The BaTiO₃ powder of claim 3 having a mean particle size of about 0.1 micron and a surface area of about 12 m2/g.
Claim 6
Dependent Claim
16 words
The BaTiO₃ powder of claim 1 doped with up to about 30 mole % of SrO.
Claim 7
Independent Claim
55 words
A method of producing BaTiO₃ powders comprising reacting barium hydroxide with titania having a particle size not greater than 0.1 micron, said reaction being conducted in a protic solvent at a temperature of at least 100°C for a period of at least 48 hours to produce BaTiO₃ having a density of at least 5.7 g/cc.
Claim 8
Independent Claim
55 words
A method of producing BaTiO₃ powders comprising reacting barium hydroxide with titania having a particle size not greater than 0.1 micron, said reaction being conducted in a protic solvent at a temperature of at least 100°C for a period of at least 48 hours to produce BaTiO₃ having a density of at least 5.7 g/cc.
Claim 9
Dependent Claim
17 words
The method of claim 6 wherein the protic solvent is water and the reaction temperature is 100-125°C.
Claim 10
Dependent Claim
16 words
The method of claim 7 wherein the titania is at least 75% by weight anatase titania.
Claim 11
Independent Claim
54 words
A method of producing BaTiO₃ powder comprising reacting barium hydroxide with a titanium alkoxide in a protic solvent at a temperature of about the normal boiling temperature of the alcohol corresponding to the alkoxide for a period of at least about 240 hours to produce BaTiO₃ having a density of at least 5.7 g/cc.
Claim 12
Independent Claim
54 words
A method of producing BaTiO₃ powder comprising reacting barium hydroxide with a titanium alkoxide in a protic solvent at a temperature of about the normal boiling temperature of the alcohol corresponding to the alkoxide for a period of at least about 240 hours to produce BaTiO₃ having a density of at least 5.7 g/cc.
Claim 13
Dependent Claim
22 words
The method of claim 9 wherein the protic solvent is water or isopropyl alcohol, the alkoxide is titanium isopropoxide or titanium ethoxide.
References Cited (Backward Citations)
No citation records indexed.
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