US3799818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and installation for manufacturing fiber reinforced sandwich tube
Assignee: Wavin BV
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Filing: 1972-04-27
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Granted: 1974-03-26
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Expires: 1992-04-27
Abstract
Abstract THE INVENTION RELATES TO A SANDWICH TUBE COMPRISING AN INNER AND AN OUTER FIBER REINFORCED LAYER OF THERMOSERTING RESIN AND A INTERMEDIATE LAYER THEREBETWEEN CONSISTING OF INORGANIC FILLER MATERIAL COATED WITH THERMOSETTING RESIN AND OBTAINED BY SPRAYING A FINELY DIVIDED RESIN INTO A MASS OF LOOSELY HELD INORGANIC FILLER MATERIAL. A NON- WOVEN IS PRESENT BETWEEN THE INTERMEDIATE LAYER AND THE OUTER FIBER REINFORCED LAYER.
Inventors
- 👤 H Bulters
- 👤 G Heidemann
- 👤 W Putter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:33
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/02; B29C70/021; B29C70/025; B29C41/00; B29C41/02; B29C41/08; B29C41/085; B29C70/04; B29C70/06; B29C70/08; B29C70/081; B29C70/083; B29C70/085; B29D; B29D23/00; B29K; B29K2105/00; B29K2105/06; B29K2105/08; B29K2105/0809; B29K2105/0854; B29K2105/10; B29K2105/101; B29K2105/12; B29K2105/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-25 | 1977-09-24 | 1978-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-25 | 1981-09-24 | 1982-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-25 | 1985-09-24 | 1986-03-26 | $7700.00 | Window Closed / Lapsed |