Patent US4670320A successfully refreshed from Google Patents.
US4670320A
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US
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Alumina formed body and method for its manufacture
Assignee: Coorstek KK
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Filing: 1986-04-24
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Granted: 1987-06-02
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Expires: 2006-04-24
Abstract
Abstract An alumina formed body comprising many long alumina elements oriented in random directions and interconnected so as to constitute a porous matrix comprising a large number of fine pores. Such a body is manufactured by reacting a glass-formed body comprising silica with aluminum at high temperature to form an alumina composite material comprising alumina, aluminum and silicon and removing aluminum and silicon from the aluminum composite material.
Inventors
- 👤 Masayoshi Yamaguchi
- 👤 Kazunori Meguro
- 👤 Shuitsu Matsuo
- 👤 Yasumi Sasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:26
CPC Classifications
C; C04; C04B; C04B38/00; C04B38/0051; C04B35/00; C04B35/01; C04B35/10; C04B35/622; C04B35/64; C04B35/65; C04B35/71; C04B35/78; C04B35/80; C04B38/04; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24355; Y10T428/249921; Y10T428/249953; Y10T428/249955; Y10T428/249956; Y10T428/249957; Y10T428/249967; Y10T428/24997; Y10T428/31
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
45 words
A formed alumina body comprising a plurality of elongated alumina elements oriented in random directions and interconnected so as to constitute a porous matrix containing a large number of fine pores having an average pore radius of from about 0.5 micron to about 1.5 microns.
Claim 2
Dependent Claim
45 words
A formed alumina body comprising a plurality of elongated alumina elements oriented in random directions and interconnected so as to constitute a porous matrix containing a large number of fine pores having an average pore radius of from about 0.5 micron to about 1.5 microns.
Claim 3
Dependent Claim
29 words
A formed alumina body according to claim 1, wherein at least about 90% of said fine pores have a pore radius of from about 0.1 micron to 10 microns.
Claim 4
Dependent Claim
18 words
A formed alumina body according to claim 1, which has an apparent porosity of less than about 30%.
Claim 5
Dependent Claim
18 words
A formed alumina body according to claim 3, which has an apparent porosity of less than about 15%.
Claim 6
Dependent Claim
19 words
A formed alumina body according to claim 3, which has an apparent porosity of from about 20% to 30%.
Claim 7
Dependent Claim
26 words
A formed alumina body according to claim 1, wherein a material comprising metal oxide, metal nitride, metal carbide or metal is provided in said porous matrix.
Claim 8
Dependent Claim
34 words
A formed alumina body according to claim 6, wherein said material is selected from the group consisting of silica, alumina, magnesium oxide, silicon nitride, aluminum nitride, titanium nitride, silicon carbide, boron carbide and silicon.
Claim 9
Independent Claim
43 words
A method of manufacturing a formed alumina body comprising the steps of: reacting a glass-formed body comprising silica with aluminum so as to form an alumina composite body comprising alumina, aluminum and silicon; and removing aluminum and silicon from said alumina composite body.
Claim 10
Independent Claim
43 words
A method of manufacturing a formed alumina body comprising the steps of: reacting a glass-formed body comprising silica with aluminum so as to form an alumina composite body comprising alumina, aluminum and silicon; and removing aluminum and silicon from said alumina composite body.
Claim 11
Dependent Claim
29 words
A method of manufacturing a formed alumina body according to claim 8, wherein said reacting step is carried out under a vacuum of from about 10 to 15 torr.
Claim 12
Dependent Claim
24 words
A method of manufacturing a formed alumina body according to claim 8, wherein said reacting step is carried out in an inert gas atmosphere.
Claim 13
Dependent Claim
35 words
A method of manufacturing a formed alumina body according to claim 8, further comprising the step of firing the resulting body at a temperature of from about 1400° to 2000° C. after said removing step.
Claim 14
Dependent Claim
39 words
A method of manufacturing an alumina formed body according to claim 8, wherein said body comprises a porous matrix, further comprising the step of impregnating material comprising metal oxide, metal nitride, metal carbide or metal into said porous matrix.
Claim 15
Dependent Claim
38 words
A method of manufacturing a formed alumina body according to claim 12, wherein said material is selected from the group consisting of silica, alumina, magnesium oxide, silicon nitride, aluminum nitride, titanium nitride, silicon carbide, boron carbide and silicon.
Claim 16
Dependent Claim
19 words
A method of manufacturing a formed alumina body according to claim 8, wherein said glass-formed body comprises quartz glass.
Claim 17
Dependent Claim
35 words
A method of manufacturing a formed alumina body according to claim 8, wherein said glass-formed body is selected from the group consisting of a single piece, a bundle of fibers or a bundle of whiskers.
Claim 18
Dependent Claim
25 words
A method of manufacturing a formed alumina body according to claim 8, wherein said removing step is carried out by treatment with an etching agent.
Claim 19
Dependent Claim
27 words
A method of manufacturing a formed alumina body according to claim 8, wherein said reacting step is carried out by immersing said glass-formed body in molten aluminum.
Claim 20
Dependent Claim
22 words
A method for manufacturing a formed alumina body according to claim 17, wherein said aluminum has a purity of at least 99%.
Claim 21
Dependent Claim
22 words
A method of manufacturing a formed alumina body according to claim 18, wherein said aluminum has a purity of at least 99.9%.
Claim 22
Dependent Claim
28 words
A method of manufacturing a formed alumina body according to claim 17, further comprising heating said alumina body at a temperature of from about 780° to 950° C.
Claim 23
Dependent Claim
26 words
A method of manufacturing a formed alumina body according to claim 8, wherein said reacting step is carried out by vapor-depositing aluminum onto said glass-formed body.
Claim 24
Dependent Claim
22 words
A method of manufacturing a formed alumina body according to claim 21, wherein said aluminum has a purity of at least 99%.
Claim 25
Dependent Claim
22 words
A method of manufacturing a formed alumina body according to claim 22, wherein said aluminum has a purity of at least 99.9%.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-01 | 1990-12-01 | 1991-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-01 | 1994-12-01 | 1995-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-01 | 1998-12-01 | 1999-06-02 | $7700.00 | Window Closed / Lapsed |