US3173929A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective oxidation of leucoanthraquinone with pyridine-n-oxide
Assignee: Polaroid Corp
•
Filing: 1960-06-16
•
Granted: 1965-03-16
•
Expires: 1980-06-16
Abstract
No abstract record available.
Inventors
- 👤 Kasman Sidney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:12
CPC Classifications
C; C09; C09B; C09B1/00; C09B1/16; C09B1/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
71 words
A PROCESS FOR SELECTIVELY OXIDIZING THE LEUCOANTHRAQUINONE NUCLEUS OF A LEUCOANTHRAQUINONE COMPOUND CONTAINING AT LEAST ONE SUBSITUENT SELECTED FROM THE CLASS CONSISTING OF ORTHO- AND PARA-DIHYDROXYPHENYL GROUPS, SAID DIHYDROXYPHENYL SUBSTITUENT BEING JOINED TO THE LEUCOANTHRAQUINONE NUCLEUS THROUGH AN AMINO GROUP PRESENT ON SAID NUCLEUS, TO FORM THE CORRESPONDING ANTHRAQUINONE DYE WITHOUT OXIDIZING SAID DIHYDROXYPHENYL SUBSTITUENT, SAID PROCESS COMPRISING REACTING SAID LEUCOANTHRAQUINONE COMPOUND WITH AT LEAST A MOLAR EQUIVALENT AMOUNT OF PYRIDINE-N-OXIDE.
Claim 2
Dependent Claim
71 words
A PROCESS FOR SELECTIVELY OXIDIZING THE LEUCOANTHRAQUINONE NUCLEUS OF A LEUCOANTHRAQUINONE COMPOUND CONTAINING AT LEAST ONE SUBSITUENT SELECTED FROM THE CLASS CONSISTING OF ORTHO- AND PARA-DIHYDROXYPHENYL GROUPS, SAID DIHYDROXYPHENYL SUBSTITUENT BEING JOINED TO THE LEUCOANTHRAQUINONE NUCLEUS THROUGH AN AMINO GROUP PRESENT ON SAID NUCLEUS, TO FORM THE CORRESPONDING ANTHRAQUINONE DYE WITHOUT OXIDIZING SAID DIHYDROXYPHENYL SUBSTITUENT, SAID PROCESS COMPRISING REACTING SAID LEUCOANTHRAQUINONE COMPOUND WITH AT LEAST A MOLAR EQUIVALENT AMOUNT OF PYRIDINE-N-OXIDE.
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) | 1968-03-15 | 1968-09-14 | 1969-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-03-15 | 1972-09-14 | 1973-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-03-15 | 1976-09-14 | 1977-03-16 | $7700.00 | Window Closed / Lapsed |