Patent US4119474A successfully refreshed from Google Patents.
US4119474A
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Microcrystalline cellulose as extrusion aid/combustible filler for alumina
Assignee: Wyeth Holdings LLC
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Filing: 1977-07-13
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Granted: 1978-10-10
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Expires: 1997-07-13
Abstract
Abstract The use of microcrystalline cellulose as an extrusion aid/combustible filler for rehydratable alumina allows the production of low density alumina substrates.
Inventors
- 👤 Robert Henry Whitman
- 👤 William Austin Barber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:24
CPC Classifications
C; C04; C04B; C04B38/00; C04B38/06; C04B38/063; C04B38/0635; C04B38/0645; C04B38/0675; B; B01; B01J; B01J21/00; B01J21/02; B01J21/04; B01J37/00; B01J37/0009; B01J37/0018; C04B35/00; C04B35/01; C04B35/10; C04B2111/00; C04B2111/00474; C04B2111/0081
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
47 words
An alumina substrate consisting essentially of extrudates made from rehydratable alumina wherein the extrudates have the following properties: ______________________________________
Pore Volume (water)
0.9-1.2 cc./g.
Crush Strength >7 lbs.
Crush Number >5 lbs.
Bulk Density (compacted)
20-32 lbs./cu. ft.
Surface Area (B.E.T.)
100-130 m.sup.2 /g.
Shrinkage <4%
______________________________________
Claim 2
Dependent Claim
47 words
An alumina substrate consisting essentially of extrudates made from rehydratable alumina wherein the extrudates have the following properties: ______________________________________
Pore Volume (water)
0.9-1.2 cc./g.
Crush Strength >7 lbs.
Crush Number >5 lbs.
Bulk Density (compacted)
20-32 lbs./cu. ft.
Surface Area (B.E.T.)
100-130 m.sup.2 /g.
Shrinkage <4%
______________________________________
Claim 3
Dependent Claim
42 words
The alumina substrate of claim 1 wherein the extrudates have the following properties: ______________________________________
Pore Volume (water) 0.9-1.1 cc./g.
Bulk Density (compacted)
26-30 lbs./cu. ft.
Crush Strength >10 lbs.
Crush Number >7 lbs.
Surface Area (B.E.T.)
100-130 m.sup.2 /g.
Shrinkage <4%
______________________________________
References Cited (Backward Citations)
US3856708A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-09 | 1982-04-10 | 1982-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-09 | 1986-04-10 | 1986-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-09 | 1990-04-10 | 1990-10-10 | $7700.00 | Window Closed / Lapsed |