US4560478A
Expired / Lapsed
US
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Porous ceramic article
Assignee: Bridgestone Corp
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Filing: 1983-02-24
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Granted: 1985-12-24
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Expires: 2003-02-24
Abstract
Abstract A porous ceramic article comprising a porous ceramic body having a three-dimensional network of strands defining interconnected cells is characterized in that at least one compound selected from the group consisting of nitrides, carbides, borides and silicides of metals is dispersed in or deposited on the strands of the porous ceramic body, and the porous ceramic body has a bulk specific gravity of 0.25 to 0.6, an average pore diameter of 0.3 to 10 mm, a porosity of 75 to 95%, and an air pressure drop of 0.1 to 30 mm in water gauge when air passes through the porous ceramic body over a thickness of 1 cm at a velocity of 1 m/sec. The porous ceramic body has improved thermal properties. When needle-like crystals are dispersed in the porous ceramic body, creep resistance and strength at high temperature are both improved.
Inventors
- 👤 Tsuneaki Narumiya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 05:15
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; B; B01; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2068; B01D39/2093; C04B38/00; C04B38/06; C04B38/0615; C04B41/45; C04B41/50; C04B41/5053; C04B41/80; C04B41/81; C04B41/85; C04B41/87
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
125 words
A porous ceramic article comprising a porous ceramic body having a three-dimensional network of strands defining interconnected cells, characterized in that the porous ceramic body has a bulk specific gravity of 0.25 to 0.6, an average pore diameter of 0.3 to 10 mm, a porosity of 75 to 95%, and an air pressure drop of 0.1 to 30 mm in water gauge when air passes through the porous ceramic body over a thickness of 1 cm at a velocity of 1 m/sec, and needle-like crystals dispersed in the porous ceramic body which is formed by heating a ceramic material containing 70-92% by weight of alumina on the basis of the weight of the porous ceramic body. deposited on the strands of the porous ceramic body.
Claim 2
Dependent Claim
125 words
A porous ceramic article comprising a porous ceramic body having a three-dimensional network of strands defining interconnected cells, characterized in that the porous ceramic body has a bulk specific gravity of 0.25 to 0.6, an average pore diameter of 0.3 to 10 mm, a porosity of 75 to 95%, and an air pressure drop of 0.1 to 30 mm in water gauge when air passes through the porous ceramic body over a thickness of 1 cm at a velocity of 1 m/sec, and needle-like crystals dispersed in the porous ceramic body which is formed by heating a ceramic material containing 70-92% by weight of alumina on the basis of the weight of the porous ceramic body. deposited on the strands of the porous ceramic body.
Claim 3
Dependent Claim
57 words
The porous ceramic article according to claim 1 wherein said porous ceramic body is prepared by applying a ceramic slurry to an open-cell synthetic resin foam, and drying and sintering the treated foam to remove the foam resin through carbonization and form a porous ceramic body having substantially the same cell configuration as the starting resin foam.
Claim 4
Dependent Claim
20 words
The porous ceramic article according to claim 2 wherein said open-cell synthetic resin foam is a reticulated flexible polyurethane foam.
Claim 5
Dependent Claim
26 words
The porous ceramic article according to claim 1 wherein the porous ceramic body is based on alumina or cordierite, and the needle-like crystals are of mullite.
Claim 6
Dependent Claim
39 words
The porous ceramic article according to claim 1 wherein at least one compound selected from the group consisting of nitrides, carbides, borides and silicides of metals is dispersed in or deposited on the strands of the porous ceramic body.
Claim 7
Dependent Claim
29 words
The porous ceramic article according to claim 5 wherein the compound dispersed in or deposited on the strands of the porous ceramic body is a metal nitride or carbide.
Claim 8
Dependent Claim
38 words
The porous ceramic article according to claim 6 wherein the metal nitrides and carbides are selected from the group consisting of TiN, ZrN, Si 3 N 4 , TiC, ZrC, HfC, VC, TaC, NbC, WC, BiC and SiC.
Claim 9
Dependent Claim
46 words
The porous ceramic article according to claim 5 wherein said article consists essentially of 99% to 3% by volume of a porous ceramic body-forming material and 1% to 97% by volume of the compound dispersed in or deposited on the strands of the porous ceramic body.
Claim 10
Dependent Claim
31 words
The porous ceramic article according to claim 1 wherein the needle-like crystals are present in an amount of 1 to 90% by weight, based on the wieght of the ceramic body.
Claim 11
Dependent Claim
31 words
The porous ceramic article according to claim 1 wherein the needle-like crystals are present in an amount of 1 to 20% by weight, based on the weight of the ceramic body.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-12-23 | 1989-06-24 | 1989-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-23 | 1993-06-24 | 1993-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-23 | 1997-06-24 | 1997-12-24 | $7700.00 | Window Closed / Lapsed |