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US4092257A
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Constant boiling admixtures of toluene/perfluoro-n-heptane
Assignee: Phillips Petroleum Co
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Filing: 1977-02-04
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Granted: 1978-05-30
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Expires: 1997-02-04
Abstract
Abstract Toluene/perfluoro-n-heptane mixtures, and employment thereof in the purification of perfluoro-n-heptane.
Inventors
- 👤 George B. Fozzard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:33
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/38; C07C19/00; C07C19/08
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
26 words
A substantially constant boiling mixture of (A) perfluoro-n-heptane and (B) toluene, characterized by a weight percent ratio of about 88.6-90.9 (A):11.4-9.1 (B) at substantially atmospheric pressure.
Claim 2
Dependent Claim
26 words
A substantially constant boiling mixture of (A) perfluoro-n-heptane and (B) toluene, characterized by a weight percent ratio of about 88.6-90.9 (A):11.4-9.1 (B) at substantially atmospheric pressure.
Claim 3
Dependent Claim
24 words
The substantially constant boiling mixture according to claim 1 characterized by a boiling point of about 73° to 75° C at substantially atmospheric pressure.
Claim 4
Dependent Claim
26 words
The substantially constant boiling mixture according to claim 1 further characterized as an azeotrope and a weight percent ratio of about 88.6 (A) and 11.4 (B).
Claim 5
Dependent Claim
26 words
The substantially constant boiling mixture according to claim 1 further characterized as an azeotrope and a weight percent ratio of about 89.9 (A) and 10.1 (B).
Claim 6
Dependent Claim
26 words
The substantially constant boiling mixture according to claim 1 further characterized as an azeotrope and a weight percent ratio of about 90.9 (A) and 9.1 (B).
Claim 7
Dependent Claim
26 words
The substantially constant boiling mixture according to claim 1 further characterized as an azeotrope and a weight percent ratio of about 90.7 (A) and 9.3 (B).
Claim 8
Dependent Claim
36 words
A binary azeotrope of perfluoro-n-heptane and toluene characterized by a relationship of about 75 mol percent perfluoro-n-heptane and 25 mol percent toluene at a boiling point of about 73° to 75° C at substantially atmospheric pressure.
Claim 9
Dependent Claim
36 words
A binary azeotrope of perfluoro-n-heptane and toluene characterized by a relationship of about 75 mol percent perfluoro-n-heptane and 25 mol percent toluene at a boiling point of about 73° to 75° C at substantially atmospheric pressure.
References Cited (Backward Citations)
US2789087A
Cited
US4029552A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-05-29 | 1981-11-28 | 1982-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-29 | 1985-11-28 | 1986-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-29 | 1989-11-28 | 1990-05-30 | $7700.00 | Window Closed / Lapsed |