Patent US3278449A successfully refreshed from Google Patents.
US3278449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Visible light filtering
Assignee: Sundstrand Corp
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Filing: 1960-12-20
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Granted: 1966-10-11
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Expires: 1980-12-20
Abstract
No abstract record available.
Inventors
- 👤 Eugene R Hardwick
- 👤 Harry S Mosher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:49
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/72; G03C1/73
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
64 words
A COMPOSITION OF MATTER CONSISTING ESSENTIALLY OF A SOLID SOLUTION OF 4-(2'',4''-DINITROBENZYL)-PYRIDINE AND SYNTHETIC RESIN, SAID PYRIDINE COMPOUND BEING DISSOLVED IN THE RESIN IN AN AMOUNT EFFECTIVE TO CAUSE A DARKENING OF THE SOLID SOLUTION UPON EXPOSURE TO VISIBLE LIGHT AND NEAR ULTRAVIOLET, SaID PYRIDINE COMPOUND BEING PRESENT IN THE RESIN IN AN AMOUNT WITHIN THE RANGE OF 0.1 WEIGHT PERCENT OF SATURATED SOLUTION.
Claim 2
Dependent Claim
64 words
A COMPOSITION OF MATTER CONSISTING ESSENTIALLY OF A SOLID SOLUTION OF 4-(2'',4''-DINITROBENZYL)-PYRIDINE AND SYNTHETIC RESIN, SAID PYRIDINE COMPOUND BEING DISSOLVED IN THE RESIN IN AN AMOUNT EFFECTIVE TO CAUSE A DARKENING OF THE SOLID SOLUTION UPON EXPOSURE TO VISIBLE LIGHT AND NEAR ULTRAVIOLET, SaID PYRIDINE COMPOUND BEING PRESENT IN THE RESIN IN AN AMOUNT WITHIN THE RANGE OF 0.1 WEIGHT PERCENT OF SATURATED SOLUTION.
Claim 3
Independent Claim
104 words
A METHOD FOR REDUCING LIGHT INTENSITY WHICH COMPRISES PROVIDING A SOLID SOLUTION OF 4-(2'',4''-DINITROBENZYL)-PYRIDINE AND A SYNTHETIC RESIN, SAID PYRIDINE COMPOUND BEING DISSOLVED IN THE SYNTHETIC RESIN IN AN AMOUNT EFFECTIVE TO CAUSE A DARKENING OF THE SOLID SOLUTION UPON EXPOSURE TO VISIBLE LIGHT AND NEAR ULTRA VIOLET RADIATION AND IN AN AMOUNT WITHIN THE RANGE OF 0.1 WEIGHT PERCENT TO SATURATED SOLUTION, AND EXPOSING SAID SOLID SOLUTION TO A RADIATION SOURCE AND CAUSING A DARKENING OF THE SOLUTION, SAID SOLUTION BEING FURTHER CHARACTERIZED BY ITS ABILITY TO RAPIDLY RETURN TO A LESS DARK FORM WITH A REDUCTION IN THE INTENSITY OF SAID RADIATION.
Claim 4
Independent Claim
104 words
A METHOD FOR REDUCING LIGHT INTENSITY WHICH COMPRISES PROVIDING A SOLID SOLUTION OF 4-(2'',4''-DINITROBENZYL)-PYRIDINE AND A SYNTHETIC RESIN, SAID PYRIDINE COMPOUND BEING DISSOLVED IN THE SYNTHETIC RESIN IN AN AMOUNT EFFECTIVE TO CAUSE A DARKENING OF THE SOLID SOLUTION UPON EXPOSURE TO VISIBLE LIGHT AND NEAR ULTRA VIOLET RADIATION AND IN AN AMOUNT WITHIN THE RANGE OF 0.1 WEIGHT PERCENT TO SATURATED SOLUTION, AND EXPOSING SAID SOLID SOLUTION TO A RADIATION SOURCE AND CAUSING A DARKENING OF THE SOLUTION, SAID SOLUTION BEING FURTHER CHARACTERIZED BY ITS ABILITY TO RAPIDLY RETURN TO A LESS DARK FORM WITH A REDUCTION IN THE INTENSITY OF SAID RADIATION.
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) | 1969-10-10 | 1970-04-11 | 1970-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-10-10 | 1974-04-11 | 1974-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-10-10 | 1978-04-11 | 1978-10-11 | $7700.00 | Window Closed / Lapsed |