US4250082A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of a pulverulent filled rubber
Assignee: Huels AG
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Filing: 1979-05-14
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Granted: 1981-02-10
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Expires: 1999-05-14
Abstract
Abstract A process for the precipitation of a pulverulent filled rubber, which comprises mixing a rubber latex, a rubber solution or a rubber emulsion with a filler suspension, waterglass and a water-soluble aluminum salt at a predetermined pH value of 3.0-3.7, the pH value being kept constant by introduction of acid during the precipitation.
Inventors
- 👤 Neithart Sommer
- 👤 Karl-Heinz Nordsiek
- 👤 Jurgen Ehrlich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:37
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/20; C08J3/205; C08J3/21; C08J3/215; C08J2321/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
77 words
A process for the precipitation of a pulverulent filled rubber, which consists essentially of mixing (a) a rubber latex; (b) a rubber solution; or (c) a rubber emulsion; with a filler suspension, waterglass and a water-soluble aluminum salt at a predetermined pH value of 3.0-3.7, the pH value being kept constant by introduction of acid during the precipitation, whereby the intermediate preparation of a stable mixture of (a), (b) or (c) with the filler suspension is avoided.
Claim 2
Dependent Claim
77 words
A process for the precipitation of a pulverulent filled rubber, which consists essentially of mixing (a) a rubber latex; (b) a rubber solution; or (c) a rubber emulsion; with a filler suspension, waterglass and a water-soluble aluminum salt at a predetermined pH value of 3.0-3.7, the pH value being kept constant by introduction of acid during the precipitation, whereby the intermediate preparation of a stable mixture of (a), (b) or (c) with the filler suspension is avoided.
Claim 3
Dependent Claim
33 words
A process for preparing a pulverulent filled rubber which comprises carrying out the process of claim 1, distilling-off any rubber solvent, separating the pulverulent filled rubber from the water and drying the rubber.
Claim 4
Dependent Claim
14 words
The process of claim 2, wherein the solvent is distilled-off simultaneously with the precipitation.
Claim 5
Dependent Claim
65 words
The process of claim 1 which comprises preparing the filler suspension by suspending the filler in water and adding thereto the waterglass and aluminum salt, and adjusting the pH of the suspension to a predetermined value of 3.0-3.7 by addition of a mineral acid; and combining the rubber with the filler suspension while maintaining the pH at the predetermined value by addition of mineral acid.
Claim 6
Dependent Claim
11 words
The process of claim 1, wherein the filler is carbon black.
Claim 7
Dependent Claim
13 words
The process of claim 1, wherein aluminum sulphate is the water-soluble aluminum salt.
Claim 8
Dependent Claim
101 words
The process of claim 1, wherein the amount of filler is 20-400 weight parts per 100 weight parts of rubber if a carbon black filler is used, or is 20-500 weight parts per 100 weight parts of rubber if a mineral filler is used; the waterglass is a sodium silicate solution in which the molar ratio, Na 2 O:SiO 2 is 2:1-1:4; the amount of waterglass is 0.5.6 weight percent (based on SiO 2 ) based on the total amount of rubber; and the amount of water soluble aluminum salt is 0.5-8 weight percent based on the total amount of rubber.
Claim 9
Dependent Claim
13 words
The pulverulent filled rubber prepared by the process of claim 1 or 2.
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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) | 1984-02-10 | 1984-08-11 | 1985-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-10 | 1988-08-11 | 1989-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-10 | 1992-08-11 | 1993-02-10 | $7700.00 | Window Closed / Lapsed |