Patent US3580067A successfully refreshed from Google Patents.
US3580067A
Expired / Lapsed
US
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Method of determining the rate of vapor transmission through sheet materials
Assignee: Dow Chemical Co
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Filing: 1967-11-02
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Granted: 1971-05-25
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Expires: 1987-11-02
Abstract
Abstract This invention relates to a method of determining the rate of vapor transmission through sheet materials wherein a defined area of test sheet material fitted over the end of a bottlelike element is exposed to standardized radioactive water under constant conditions of temperature and humidity. Radioactive water which penetrates the test sheet is, for example, absorbed on calcium chloride. After a known time interval the calcium chloride is analyzed for radioactivity by means of liquid scintillation counting. The vapor transmission rate is calculated from the amount of radioactivity present in the calcium chloride.
Inventors
- 👤 Melford E Mandrell
- 👤 Wayne W Blaser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:59
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-24 | 1974-11-23 | 1975-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-24 | 1978-11-23 | 1979-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-24 | 1982-11-23 | 1983-05-25 | $7700.00 | Window Closed / Lapsed |