US4270954A
Expired / Lapsed
US
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Inorganic fibers
Assignee: Evonik Operations GmbH
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Filing: 1977-04-28
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Granted: 1981-06-02
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Expires: 1997-04-28
Abstract
Abstract The invention provides inorganic fibers based on calcium sulfate dihydrate or calcium sulfate aluminate hydrate (or their dehydration products), wherein the ratio of average length to diameter of the fibers is more than 100:1 and the length of the fibers is at least 0.2 mm; preferably the ratio of average length to diameter is 300-800:1, and the length is 0.5-6 mm.
Inventors
- 👤 Alois Aignesberger
- 👤 Walter Lukas
- 👤 Ekkehard Weinberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:45
CPC Classifications
C; C01; C01F; C01F11/00; C01F11/46; C01F7/00; C01F7/68; C01F7/74; C01F7/76; C01F7/767; C04; C04B; C04B14/00; C04B14/38; C08; C08K; C08K7/00; C08K7/02; C08K7/04; C01P; C01P2004/00; C01P2004/10; C01P2004/54; C01P2004/60; C01P2004/61; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12486
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
36 words
Inorganic fibers based on calcium sulfate dihydrate or calcium sulfate aluminate hydrate, or their dehydration products, having a ratio of average length to diameter of more than 100:1 and a length of at least 0.2 mm.
Claim 2
Dependent Claim
36 words
Inorganic fibers based on calcium sulfate dihydrate or calcium sulfate aluminate hydrate, or their dehydration products, having a ratio of average length to diameter of more than 100:1 and a length of at least 0.2 mm.
Claim 3
Dependent Claim
16 words
Fibers as claimed in claim 1, having a ratio of average length to diameter of 300-800:1.
Claim 4
Dependent Claim
12 words
Fibers as claimed in claim 1, having a length of 0.5-6 mm.
Claim 5
Dependent Claim
13 words
Fibers as claimed in claim 1, having a coating of known fiber dressing.
Claim 6
Dependent Claim
20 words
Matrix material having improved mechanical properties comprising a matrix material and, incorporated therein, inorganic fibers as claimed in claim 1.
Claim 7
Dependent Claim
23 words
Additive composition as claimed in claim 5, wherein said matrix material is a plastic, cellulose, an inorganic binder, a glass or a metal.
References Cited (Backward Citations)
US3822340A
Cited
JPS50109295A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-01 | 1984-12-01 | 1985-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-01 | 1988-12-01 | 1989-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-01 | 1992-12-01 | 1993-06-02 | $7700.00 | Window Closed / Lapsed |