US2882254A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preservation of the fluidity of polymethylmethacrylate by the addition of finely divied silica
Assignee: Evonik Operations GmbH
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Filing: 1954-11-23
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Granted: 1959-04-14
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Expires: 1974-11-23
Abstract
No abstract record available.
Inventors
- 👤 Kloepfer Harry
- 👤 Schweitzer Otto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:55
CPC Classifications
B; B01; B01J; B01J2/00; B01J2/30; C; C08; C08K; C08K3/00; C08K3/34; C08K3/36
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
71 words
A PROCESS OR IMPROVING AND PRESERVING FLUIDITY IN A DRY POWDERED MASS OF FINELY DIVIDED POLYMETHYLMETHACRYLATE RESIN CHARACTERIZED BY THE STEP OF ADDING TO ATHE POWDERED RESIN 0.01 TO 1.0% BY WEIGHT OF SIO2 OF PARTICLE SIZE APPROXIMATELY 10 TO LESS THAN 50 MILLIMICRONS, THEREBY REDUCING THE ANGLE OF REPOSE PF THE POWDERED MIXTURE AS COMPARED TO THAT OF THE UNMIXED POWDERED RESIN AND ADAPTING THE MIXTURE FOR MOLDING EITHOUT DISCOLORATION.
Claim 2
Dependent Claim
71 words
A PROCESS OR IMPROVING AND PRESERVING FLUIDITY IN A DRY POWDERED MASS OF FINELY DIVIDED POLYMETHYLMETHACRYLATE RESIN CHARACTERIZED BY THE STEP OF ADDING TO ATHE POWDERED RESIN 0.01 TO 1.0% BY WEIGHT OF SIO2 OF PARTICLE SIZE APPROXIMATELY 10 TO LESS THAN 50 MILLIMICRONS, THEREBY REDUCING THE ANGLE OF REPOSE PF THE POWDERED MIXTURE AS COMPARED TO THAT OF THE UNMIXED POWDERED RESIN AND ADAPTING THE MIXTURE FOR MOLDING EITHOUT DISCOLORATION.
References Cited (Backward Citations)
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Cited
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Cited
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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) | 1962-04-13 | 1962-10-13 | 1963-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-13 | 1966-10-13 | 1967-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-13 | 1970-10-13 | 1971-04-14 | $7700.00 | Window Closed / Lapsed |