US5009874A
Expired / Lapsed
US
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Hydrophobic precipitated silica granules
Assignee: Rhodia Chimie SAS
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Filing: 1988-04-13
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Granted: 1991-04-23
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Expires: 2008-04-13
Abstract
Abstract Hydrophobic, essentially spheroidal precipitated silica particulates, well adapted as a reinforcing filler material for silicone elastomers, have a density of at least 0.15, a water wettability of at least 20% and a maximum water uptake of 5%.
Inventors
- 👤 Francois Parmentier
- 👤 Jacques Persello
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:40
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C09; C09C; C09C1/00; C09C1/28; C09C1/30; C09C1/309; C01B33/18; C01B33/187; C01B33/193; C08; C08K; C08K3/00; C08K3/34; C08K3/36; C01P; C01P2004/00; C01P2004/30; C01P2004/32; C01P2004/50; C01P2006/00; C01P2006/10; C01P2006/12; C01P2006/19; C01P2006/80; C01P2006/90
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
36 words
Hydrophobic, essentially spheroidal precipitated silica granules having a median particle size of at least 0.08 mm, a density of at least 0.15, a water wettability of at least 20%, and a maximum water uptake of 5%.
Claim 2
Dependent Claim
36 words
Hydrophobic, essentially spheroidal precipitated silica granules having a median particle size of at least 0.08 mm, a density of at least 0.15, a water wettability of at least 20%, and a maximum water uptake of 5%.
Claim 3
Dependent Claim
17 words
The precipitated silica granules as defined by claim 1, having a density ranging from 0.2 to 0.4.
Claim 4
Dependent Claim
17 words
The precipitated silica granules as defined by claim 1, having a water wettability of at least 30%.
Claim 5
Dependent Claim
18 words
The precipitated silica granules as defined by claim 3, having a water wettability ranging from 40% to 80%.
Claim 6
Dependent Claim
16 words
The precipitated silica granules as defined by claim 1, having a maximum water uptake of 3%.
Claim 7
Dependent Claim
18 words
The precipitated silica granules as defined by claim 1, having a water uptake ranging from 1.5% to 3%.
Claim 8
Dependent Claim
20 words
The precipitated silica granules as defined by claim 1, having a median particle size ranging from 0.2 to 2 mm.
Claim 9
Dependent Claim
33 words
The precipitated silica granules as defined by claim 1, having a BET surface area of at least 50 m 2 /g and a CTAB surface area of at least 40 m 2 /g.
Claim 10
Dependent Claim
35 words
The precipitated silica granules as defined by claim 8, having a BET surface area of from 50 to 350 m 2 /g and a CTAB surface area of from 40 to 320 m 2 /g.
References Cited (Backward Citations)
FR2305390A1
Cited
US4015031A
Cited
FR2356596A1
Cited
US4273589A
Cited
US4308074A
Cited
EP0031288A2
Cited
US4409356A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-04-22 | 1994-10-22 | 1995-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-04-22 | 1998-10-22 | 1999-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-04-22 | 2002-10-22 | 2003-04-23 | $7700.00 | Window Closed / Lapsed |