Patent US4290951A successfully refreshed from Google Patents.
US4290951A
Expired / Lapsed
US
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3,6-Di(N-indolinyl)-9-sulfonamidophenyl-xanthenes
Assignee: Polaroid Corp
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Filing: 1980-05-30
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Granted: 1981-09-22
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Expires: 2000-05-30
Abstract
Abstract In one embodiment, the present invention is concerned with novel xanthene compounds of the formula ##STR1## wherein X is ##STR2## wherein R' is alkyl; Y is an electron-withdrawing group and A is an anion. In another embodiment, the present invention is concerned with photographic products and processes employing these xanthene compounds.
Inventors
- 👤 James W. Foley
- 👤 Louis Locatell, Jr.
- 👤 Charles M. Zepp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:12
CPC Classifications
G; G03; G03C; G03C8/00; G03C8/42; G03C8/44; G03C8/48; C; C09; C09B; C09B11/00; C09B11/04; C09B11/10; C09B11/24; C09B11/28; G03C1/00; G03C1/76; G03C1/825; G03C1/83
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
32 words
A compound of the formula ##STR31## wherein X is ##STR32## wherein R' is methyl; Y is an electron-withdrawing group having a positive sigma value greater than 0.60; and A is an anion.
Claim 2
Dependent Claim
32 words
A compound of the formula ##STR31## wherein X is ##STR32## wherein R' is methyl; Y is an electron-withdrawing group having a positive sigma value greater than 0.60; and A is an anion.
Claim 3
Dependent Claim
12 words
A compound as defined in claim 1 wherein said X is ##STR33##
Claim 4
Dependent Claim
11 words
A compound as defined in claim 1 wherein X is ##STR34##
Claim 5
Dependent Claim
3 words
The compound ##STR35##
Claim 6
Dependent Claim
3 words
The compound ##STR35##
Claim 7
Dependent Claim
3 words
The compound ##STR36##
Claim 8
Dependent Claim
3 words
The compound ##STR36##
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-09-21 | 1985-03-23 | 1985-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-21 | 1989-03-23 | 1989-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-21 | 1993-03-23 | 1993-09-22 | $7700.00 | Window Closed / Lapsed |