Patent US3657272A successfully refreshed from Google Patents.
US3657272A
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US
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Process for preparing x-form metalfree phthalocyanine
Assignee: Xerox Corp
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Filing: 1970-12-21
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Granted: 1972-04-18
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Expires: 1990-12-21
Abstract
Abstract A PROCESS OF PREPARING X-FORM METAL FREE PHTHALOCYANINE COMPRISING THE STEPS OF MIXING PHTHALONITRILE IN AN AMMONIA-SATURATED ALKYLALKANOLAMINE SOLVENT, SEEDING THE MIXTURE WITH A CATALYTIC AMOUNT OF X-FORM PHTHALOCYANINE, HEATING SAID MIXTURE TO REFLUX TEMPERATURE AND MAINTAINING SAID TEMPERATURE FOR ABOUT 20 TO ABOUT 70 MINUTES, AND FILTERING THE HOT REACTION PRODUCT FORMED THEREBY IS DISCLOSED.
Inventors
- 👤 Paul J Brach
- 👤 Hugh A Six
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:12
CPC Classifications
C; C09; C09B; C09B47/00; C09B47/04; C09B47/30; C09B67/00; C09B67/0025; C09B67/0026
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) | 1975-04-18 | 1975-10-18 | 1976-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-18 | 1979-10-18 | 1980-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-18 | 1983-10-18 | 1984-04-18 | $7700.00 | Window Closed / Lapsed |