Patent US3615531A successfully refreshed from Google Patents.
US3615531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Antistatic layers containing polymers of sulfo-substituted n-phenyl maleic imides
Assignee: Agfa Gevaert AG
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Filing: 1969-12-02
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Granted: 1971-10-26
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Expires: 1989-12-02
Abstract
Abstract A photographic material with improved antistatic properties. The material contains an outermost antistatic layer of a polymer containing N-phenyl maleic imides units.
Inventors
- 👤 Karl-Otto Meyer
- 👤 Wulf Von Bonin
- 👤 Wolfgang Himmelmann
- 👤 Julius Geiger
- 👤 Werner Wagenknecht
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:46
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/76; G03C1/85; G03C1/89; C; C08; C08F; C08F8/00; C08F8/48
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
22 words
The photographic material as claimed in claim 1 wherein the said polymer has a molecular weight of between 50,000 and 500, 000.
Claim 2
Dependent Claim
27 words
The photographic material as claimed in claim 1 wherein the copolymer contains not more than 60 mol percent of units of styrene, sulfosubstituted styrene, ethylene or isobutylene.
Claim 3
Dependent Claim
26 words
A photographic material according to claim 1, characterized in that the polymer contains 40 to 60 mol percent of units of a sulfosubstituted N-phenyl maleic imide.
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) | 1974-10-25 | 1975-04-26 | 1975-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-25 | 1979-04-26 | 1979-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-25 | 1983-04-26 | 1983-10-26 | $7700.00 | Window Closed / Lapsed |