US2889257A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Distillation of tar residues
Assignee: EIDP Inc
•
Filing: 1956-05-17
•
Granted: 1959-06-02
•
Expires: 1976-05-17
Abstract
No abstract record available.
Inventors
- 👤 Samuel E C Griffin
- 👤 Wilford E Railing
- 👤 Yacoe Jesse Craig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:18
CPC Classifications
C; C07; C07C; C07C263/00; C07C263/18; C07C263/20; Y; Y10; Y10S; Y10S159/00; Y10S159/25
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
114 words
A PROCESS FOR RECOVERING ORGANIC ISOYANATES FROM THE CRUDE REACTION MIXTURES IN WHICH THEY ARE FORMED DURING THEIR MANUFACTURE OR FROM CONCENTRATED TARRY RESIDUES AFTER PRELIMINARY DISTILLATION OF A SUBSTANTIAL PORTION OF THE ORGANIC ISOCYANATES THEREFROM, WHICH COMPRISES DROPPING THE ORGANIC ISOCYANATE SOLUTION CONTAINING THE NON-VOLATIEL TARRY RESIDUE INTO A NAPHTHENIC HYDROCARBON OIL WHICH IS HELD AT A TEMPERATURE OF FROM 200* TO 315*C. AND AT FROM 1 TO 80 MM. MERCURY PRESSURE WHEREBY THE ORGANIC ISOCYANATE IS VAPORIZED AND THE INSOLUBLE RESIDUE IS CONVERTED TO A READILY FILTERABLE GRANULAR SOLID IN THE OIL, SAID NAPHTHENIC HYDROCARBON OIL BEING ONE THAT DOES NOT DECOMPOSE OR DIDSTILL AT THE TEMPERATURE AND UNDER THE PRESSURE EMPLOYED.
Claim 2
Dependent Claim
114 words
A PROCESS FOR RECOVERING ORGANIC ISOYANATES FROM THE CRUDE REACTION MIXTURES IN WHICH THEY ARE FORMED DURING THEIR MANUFACTURE OR FROM CONCENTRATED TARRY RESIDUES AFTER PRELIMINARY DISTILLATION OF A SUBSTANTIAL PORTION OF THE ORGANIC ISOCYANATES THEREFROM, WHICH COMPRISES DROPPING THE ORGANIC ISOCYANATE SOLUTION CONTAINING THE NON-VOLATIEL TARRY RESIDUE INTO A NAPHTHENIC HYDROCARBON OIL WHICH IS HELD AT A TEMPERATURE OF FROM 200* TO 315*C. AND AT FROM 1 TO 80 MM. MERCURY PRESSURE WHEREBY THE ORGANIC ISOCYANATE IS VAPORIZED AND THE INSOLUBLE RESIDUE IS CONVERTED TO A READILY FILTERABLE GRANULAR SOLID IN THE OIL, SAID NAPHTHENIC HYDROCARBON OIL BEING ONE THAT DOES NOT DECOMPOSE OR DIDSTILL AT THE TEMPERATURE AND UNDER THE PRESSURE EMPLOYED.
References Cited (Backward Citations)
US2151990A
Cited
US2315422A
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US2406648A
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US2417131A
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US2474735A
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US2502485A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-06-01 | 1962-12-01 | 1963-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-06-01 | 1966-12-01 | 1967-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-06-01 | 1970-12-01 | 1971-06-02 | $7700.00 | Window Closed / Lapsed |