Patent US3671248A successfully refreshed from Google Patents.
US3671248A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stain inhibitor in photographic paper bases
Assignee: Eastman Kodak Co
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Filing: 1970-06-10
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Granted: 1972-06-20
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Expires: 1990-06-10
Abstract
Abstract PHOTOGRAPHIC ELEMENTS HAVING POLYOLEFIN COATED PAPER SUPPORTS, PROVIDED WITH SILVER HALIDE EMULSION LAYERS CONTAINING SILVER HALIDE DEVELOPING AGENTS, WITH OR WITHOUT HYDROPHILIC BACKING LAYERS, EXHIBIT STAIN DUE TO MIGRATION OF THE DEVELOPING AGENT TO PAPER AND TO THE BACKING LAYER. STAIN IS AVOIDED BY SIZING THE PAPER WITH AN ALDEHYDE BISULFITE AND COATING ANY BACKING LAYER AT A PH LESS THEN 7 PREFERABLY ABOUT 3 TO 4.
Inventors
- 👤 Merle K Eldridge
- 👤 Roy C Bloom
- 👤 Douglas C Joseph
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:06
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/42; G03C1/76; G03C1/775; G03C1/79
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) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |