Patent US4234074A successfully refreshed from Google Patents.
Patent US5384306A successfully refreshed from Google Patents.
US5384306A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fine-particle oxide ceramic powders
Assignee: H.C. Starck GmbH
•
Filing: 1993-04-27
•
Granted: 1995-01-24
•
Expires: 2013-04-27
Abstract
Abstract The invention relates to fine-particle oxide ceramic powders of the metal oxides MeO, where Me=Al, Si, Zr, Hf, Ta, Nb, Mo, W, V, La and/or Y, Al 2 O 3 being present in the α-phase and SiO 2 being present in crystalline form.
Inventors
- 👤 Theo Konig
- 👤 Dietmar Fister
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:29
CPC Classifications
C; C01; C01B; C01B13/00; C01B13/14; C01B13/20; C01B13/22; C04; C04B; C04B35/00; B; B01; B01J; B01J19/00; B82; B82Y; B82Y30/00; C01F; C01F7/00; C01F7/02; C01F7/30; C01F7/302; C01G; C01G25/00; C01G25/02; C04B35/01; C04B35/10; C04B35/48; C04B35/622; C04B35/626; C01P; C01P2004/00; C01P2004/51; C01P2004/52; C01P2004/60; C01P2004/62; C01P2004/64; C01P2006/00; C01P2006/12; C01P2006/80
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
98 words
Fine-particle oxide ceramic powders of the metal oxides MeO, where Me=at least one of Al, Si, Zr, Hf, Ta, Nb, Mo, W, V, La and Y, wherein the powders have a particle size of 1.0 nm to 500 nm and less than 1% of the individual particles of said powder deviate by more than 40% from the average particle size and no individual particles of said powder deviate by more than 60% from the average particle size, further wherein any Al 2 O 3 present is in the α-phase and any SiO 2 present is in crystalline form.
Claim 2
Dependent Claim
98 words
Fine-particle oxide ceramic powders of the metal oxides MeO, where Me=at least one of Al, Si, Zr, Hf, Ta, Nb, Mo, W, V, La and Y, wherein the powders have a particle size of 1.0 nm to 500 nm and less than 1% of the individual particles of said powder deviate by more than 40% from the average particle size and no individual particles of said powder deviate by more than 60% from the average particle size, further wherein any Al 2 O 3 present is in the α-phase and any SiO 2 present is in crystalline form.
Claim 3
Dependent Claim
38 words
Powders as claimed in claim 1, wherein less than 1% of the individual particles deviate by more than 20% from the average particle size and no individual particles deviate by more than 50% from the average particle size.
Claim 4
Dependent Claim
38 words
Powders as claimed in claim 1, wherein less than 1% of the individual particles deviate by more than 10% from the average particle size and no individual particles deviate by more than 40% from the average particle size.
Claim 5
Dependent Claim
21 words
Powders as claimed in claim 1, wherein the particle size is in the range from 1 to less than 100 nm.
Claim 6
Dependent Claim
21 words
Powders as claimed in claim 1, wherein the particle size is in the range from 1 to less than 50 nm.
Claim 7
Dependent Claim
14 words
Powders as claimed in claim 1, wherein the metal oxide is ZrO 2 .
Claim 8
Dependent Claim
16 words
Powders as claimed in claim 1, wherein the metal oxide is α-Al 2 O 3 .
Claim 9
Dependent Claim
17 words
Powders as claimed in claim 1, wherein the sum total of impurities is less than 5000 ppm.
Claim 10
Dependent Claim
17 words
Powders as claimed in claim 1, wherein the sum total of impurities is less than 1000 ppm.
Claim 11
Dependent Claim
17 words
Powders as claimed in claim 1, wherein the sum total of impurities is less than 200 ppm.
Claim 12
Dependent Claim
18 words
Powders as claimed in claim 1, wherein the powders are produced in quantities of more than 1 kg.
Claim 13
Dependent Claim
16 words
Powders as claimed in claim 1, wherein the metal oxide is SiO 2 in crystalline form.
Claim 14
Dependent Claim
16 words
Powders as claimed in claim 1, wherein the metal oxide is Nb 2 O 5 .
References Cited (Backward Citations)
US4642207A
Cited
EP0151490A2
Cited
EP0152957A2
Cited
US4689075A
Cited
US4994107A
Cited
US4769064A
Cited
EP0379910A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-01-23 | 1998-07-25 | 1999-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-01-23 | 2002-07-25 | 2003-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-01-23 | 2006-07-25 | 2007-01-24 | $7700.00 | Window Closed / Lapsed |