US4937209A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Porous inorganic materials
Assignee: Imerys Minerals Ltd
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Filing: 1988-09-23
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Granted: 1990-06-26
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Expires: 2008-09-23
Abstract
Abstract There is provided a porous cellular material comprising a plurality of cavities each defined by a substantially spherical wall formed of a rigid intermeshing matrix of ceramic needles said wall being pierced by at least one aperture to provide access to the cavity, and the or each aperture having a diameter such that the ratio of the diameter of the aperture to the diameter of the cavity into which the aperture opens is in the range of from 0.1:1 to 1:1.
Inventors
- 👤 Thomas R. Jones
- 👤 Caryl Gould
- 👤 Alan J. Brown
- 👤 Roger James
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:15
CPC Classifications
C; C04; C04B; C04B38/00; C04B38/0051; B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/16; C04B38/009; C12; C12N; C12N11/00; C12N11/14; D; D21; D21H; D21H17/00; D21H17/63; D21H17/67; D21H17/68
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
82 words
A porous cellular material comprising a plurality of cavities each defined by a substantially spherical wall formed of a rigid intermeshing matrix of ceramic needles selected from mullite or cordierite said wall being pierced by at least one aperture to access to the cavity, and the or each aperture having a diameter such that the ratio of the diameter of the aperture to the diameter of the cavity into which the aperture opens is in the range of from 0.1:1 to 1:1.
Claim 2
Dependent Claim
82 words
A porous cellular material comprising a plurality of cavities each defined by a substantially spherical wall formed of a rigid intermeshing matrix of ceramic needles selected from mullite or cordierite said wall being pierced by at least one aperture to access to the cavity, and the or each aperture having a diameter such that the ratio of the diameter of the aperture to the diameter of the cavity into which the aperture opens is in the range of from 0.1:1 to 1:1.
Claim 3
Dependent Claim
19 words
A porous material according to claim 1, wherein the wall surrounding each cavity consists of intermeshing needles of mullite.
Claim 4
Dependent Claim
21 words
A porous material according to claim 1, wherein each cavity is defined by the shell or wall of a discrete particle.
Claim 5
Dependent Claim
23 words
A porous material according to claim 1, wherein each cavity has a diameter in the range of from 5 microns to 5 mm.
Claim 6
Dependent Claim
23 words
A porous material according to claim 4, wherein each cavity has a diameter in the range of from 20 microns to 120 microns.
Claim 7
Dependent Claim
25 words
A porous material according to claim 1, wherein the wall defining the cavities has a thickness in the range of from 2 to 20 microns.
Claim 8
Dependent Claim
26 words
A porous material according to claim 6, wherein the wall defining each cavity has a thickness in the range of from 5 microns to 10 microns.
Claim 9
Dependent Claim
19 words
A porous material according to claim 1, wherein the wall surrounding each cavity is pierced by a single aperture.
Claim 10
Dependent Claim
38 words
A porous material according to claim 1, wherein the ratio of the diameter of the or each aperture to the diameter of the cavity into which the aperture opens is in the range of from 0.1:1 to 0.75:1.
Claim 11
Dependent Claim
28 words
A porous material according to claim 3, wherein the volume of each internal cavity of a particle is from 50% to 90% of the volume of the particle.
Claim 12
Dependent Claim
38 words
A porous material according to claim 1 wherein a plurality of said cavities are formed in a single body, which body has a structure which is a rigid intermeshing matrix of ceramic needles selected from mullite or cordierite.
Claim 13
Dependent Claim
19 words
A porous cellular material according to claim 3, wherein substantially all of the particles of the material are anisotropic.
References Cited (Backward Citations)
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US2939764A
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GB1213093A
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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) | 1993-06-25 | 1993-12-25 | 1994-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-25 | 1997-12-25 | 1998-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-25 | 2001-12-25 | 2002-06-26 | $7700.00 | Window Closed / Lapsed |