Patent US3028397A successfully refreshed from Google Patents.
US3028397A
Expired / Lapsed
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Isothiocyanates of phthaleins
Assignee: Hexion Inc
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Filing: 1959-03-24
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Granted: 1962-04-03
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Expires: 1979-03-24
Abstract
No abstract record available.
Inventors
- 👤 Kwan C Tsou
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:32
CPC Classifications
C; C09; C09B; C09B11/00; C09B11/04; C09B11/10; C09B11/24; C09B11/245; Y; Y10; Y10S; Y10S436/00; Y10S436/80; Y10S436/826
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
124 words
THE PROCESS OF MAKING A PHTHALEIN ISOTHIOCYANATE WHICH COMPRISES MIXING AN ALKYL THIOCARBONATE HAVING 1-3 CARBON ATOMS TO THE MOLECULE WITH AN AMINE OF A PHTHALEIN SELECTED FROM THE GROUP CONSISTING OF FLUORESCEIN, EOSIN, RHODAMINE, PHLOXINE, AND THEIR ALKALI METAL SALTS, AN ORGANIC LIQUID SOLVENT FOR THE SAID THIOCARBONATE AND AMINE THAT IS CHEMICALLY NON-REACTIVE WITH BOTH, AND A METAL ALKOXIDE THAT IS SOLUBLE IN THE SAID SOLVENT, MAINTAINING THE MINERALS OF THE RESULTING MIXTURE IN CONTACT WITH EACH OTHER UNTIL CHEMICAL CHANGE SUBSTANTIALLY CEASES, SAID CHANGE GIVING THE ISOTHIOCYANATE OF THE SELECTED PHTHALEIN, AND THEN SEPARATING THE SAID ISOTHIOCYANATE FROM OTHER MATERIALS IN THE REACTION MIXTURE, THE PROPORTION OF THE SAID THIOCARBONATE USED BEING AT LEAST APPROXIMATELY 1 MOLE FOR 1 OF AMINE.
Claim 2
Dependent Claim
124 words
THE PROCESS OF MAKING A PHTHALEIN ISOTHIOCYANATE WHICH COMPRISES MIXING AN ALKYL THIOCARBONATE HAVING 1-3 CARBON ATOMS TO THE MOLECULE WITH AN AMINE OF A PHTHALEIN SELECTED FROM THE GROUP CONSISTING OF FLUORESCEIN, EOSIN, RHODAMINE, PHLOXINE, AND THEIR ALKALI METAL SALTS, AN ORGANIC LIQUID SOLVENT FOR THE SAID THIOCARBONATE AND AMINE THAT IS CHEMICALLY NON-REACTIVE WITH BOTH, AND A METAL ALKOXIDE THAT IS SOLUBLE IN THE SAID SOLVENT, MAINTAINING THE MINERALS OF THE RESULTING MIXTURE IN CONTACT WITH EACH OTHER UNTIL CHEMICAL CHANGE SUBSTANTIALLY CEASES, SAID CHANGE GIVING THE ISOTHIOCYANATE OF THE SELECTED PHTHALEIN, AND THEN SEPARATING THE SAID ISOTHIOCYANATE FROM OTHER MATERIALS IN THE REACTION MIXTURE, THE PROPORTION OF THE SAID THIOCARBONATE USED BEING AT LEAST APPROXIMATELY 1 MOLE FOR 1 OF AMINE.
References Cited (Backward Citations)
US2937186A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-04-02 | 1965-10-02 | 1966-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-04-02 | 1969-10-02 | 1970-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-04-02 | 1973-10-02 | 1974-04-03 | $7700.00 | Window Closed / Lapsed |