Patent US4250898A successfully refreshed from Google Patents.
US4250898A
Expired / Lapsed
US
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Carbon dioxide impregnation of tobacco by super cooling
Assignee: Philip Morris USA Inc
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Filing: 1978-10-13
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Granted: 1981-02-17
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Expires: 1998-10-13
Abstract
Abstract A process for impregnating tobacco with carbon dioxide is provided. The process comprises: (a) contacting tobacco with carbon dioxide gas at relatively low pressure (b) rapidly cooling the tobacco-carbon dioxide system until the carbon dioxide condenses as liquid or solid within the tobacco and finally solidifies, and (c) releasing the pressure in the cooled system. Thereafter, the carbon dioxide-treated tobacco may be expanded conventionally, such as by subjecting it to heating conditions effective to liberate the carbon dioxide therein.
Inventors
- 👤 Francis V. Utsch
- 👤 Roger Z. de la Burde
- 👤 Patrick E. Aument
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:18
CPC Classifications
A; A24; A24B; A24B3/00; A24B3/18; A24B3/182; A24B3/185
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
50 words
A process for impregnating tobacco with carbon dioxide comprising the steps of: (a) contacting tobacco with gaseous carbon dioxide at a pressure of at least 50 psig; and (b) rapidly cooling the carbon dioxide/tobacco system to a temperature where much of the carbon dioxide condenses and solidifies within the tobacco.
Claim 2
Dependent Claim
50 words
A process for impregnating tobacco with carbon dioxide comprising the steps of: (a) contacting tobacco with gaseous carbon dioxide at a pressure of at least 50 psig; and (b) rapidly cooling the carbon dioxide/tobacco system to a temperature where much of the carbon dioxide condenses and solidifies within the tobacco.
Claim 3
Dependent Claim
18 words
The process of claim 1 wherein the pressure in step (a) is between about 50 and 250 psig.
Claim 4
Dependent Claim
18 words
The process of claim 1 wherein the system is cooled to at least -70° C. in step (b).
Claim 5
Dependent Claim
24 words
The process of claim 1 wherein the system is cooled in step (b) until the pressure thereof drops to no more than 20 psig.
Claim 6
Dependent Claim
31 words
The process of claim 1 which further comprises maintaining the pressure of the system during the initial portion of step (b) by continuing to admit carbon dioxide gas to the system.
Claim 7
Dependent Claim
78 words
A process for expanding tobacco comprising the steps of: (a) contacting tobacco with gaseous carbon dioxide under a pressure of at least 50 psig; (b) rapidly cooling the carbon dioxide/tobacco system to a temperature where the carbon dioxide condenses and solidifies within the tobacco to accomplish impregnation; (c) releasing the pressure of the system; and (d) thereafter heating the impregnated tobacco under conditions effective to liberate the carbon dioxide therein so as to cause expansion of the tobacco.
Claim 8
Dependent Claim
78 words
A process for expanding tobacco comprising the steps of: (a) contacting tobacco with gaseous carbon dioxide under a pressure of at least 50 psig; (b) rapidly cooling the carbon dioxide/tobacco system to a temperature where the carbon dioxide condenses and solidifies within the tobacco to accomplish impregnation; (c) releasing the pressure of the system; and (d) thereafter heating the impregnated tobacco under conditions effective to liberate the carbon dioxide therein so as to cause expansion of the tobacco.
Claim 9
Dependent Claim
17 words
The process of claim 6 wherein the pressure is reduced to substantially atmospheric pressure in step (c).
Claim 10
Dependent Claim
22 words
The process of claim 6 wherein the tobacco is heated to a temperature between about 100° to 370° C. in step (d).
References Cited (Backward Citations)
GB1444309A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-17 | 1984-08-18 | 1985-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-17 | 1988-08-18 | 1989-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-17 | 1992-08-18 | 1993-02-17 | $7700.00 | Window Closed / Lapsed |