US3572090A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for testing paperboard
Assignee: Fibreboard Corp
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Filing: 1968-06-03
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Granted: 1971-03-23
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Expires: 1988-06-03
Abstract
Abstract A DEVICE FOR MEASURING THE RATE AT WHICH LIQUIDS ARE ABSORBED INTO THE CUT EDGE OF PAPERBOARD COMPRISES MATING TOP AND BOTTOM SECTIONS WHICH ENGAGE A SAMPLE OF PAPERBOARD AT THEIR PERIPHERAL EDGES AND FORM AN INTERNAL CHAMBER WITH ONLY A CONTINUOUS CUT EDGE OF THE PAPERBOARD EXPOSED TO LIQUID IN THE CHAMBER. A SOURCE OF LIQUID IS PROVIDED TO FILL THE CHAMBER AND A CALIBRATED CAPILLARY TUBE IS PROVIDED SO THAT THE RATE OF ABSORPTION MAY BE DETERMINED BY MEASURING THE TIME REQUIRED FOR A GIVEN AMOUNT OF LIQUID TO BE ABSORBED.
Inventors
- 👤 Richard M Graham
- 👤 Gordon C Wheeler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 13:24
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/34; G01N33/346
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) | 1974-03-22 | 1974-09-21 | 1975-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-22 | 1978-09-21 | 1979-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-22 | 1982-09-21 | 1983-03-23 | $7700.00 | Window Closed / Lapsed |