Patent US4235250A successfully refreshed from Google Patents.
US4235250A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the expansion of tobacco
Assignee: Philip Morris USA Inc
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Filing: 1978-03-29
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Granted: 1980-11-25
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Expires: 1998-03-29
Abstract
Abstract In a process for the expansion of tobacco comprising the steps of: (1) contacting tobacco with carbon dioxide gas at a pressure of at least 250 psig for a time sufficient to impregnate the tobacco with the carbon dioxide gas to form a gaseous carbon dioxide-tobacco system, (2) releasing the pressure and (3) thereafter subjecting the carbon dioxide-treated tobacco to rapid heating conditions to remove the carbon dioxide and thereby expand the tobacco, the improvement comprising cooling the gaseous carbon dioxide and tobacco system in step (1) to a temperature close to the saturation temperature of carbon dioxide but not lower than -23 DEG C.
Inventors
- 👤 Francis V. Utsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:29
CPC Classifications
A; A24; A24B; A24B3/00; A24B3/18; A24B3/182; Y; Y10; Y10S; Y10S131/00; Y10S131/90
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
104 words
In a process for the expansion of tobacco comprising the steps of: (1) contacting tobacco with carbon dioxide gas at a pressure of at least 250 psig for a time sufficient to impregnate the tobacco with the carbon dioxide gas to form a gaseous carbon dioxide-tobacco system, (2) releasing the pressure and (3) thereafter subjecting the carbon dioxide-treated tobacco to rapid heating conditions to remove the carbon dioxide and thereby expand the tobacco, the improvement comprising cooling the gaseous carbon dioxide and tobacco system in step (1) to a temperature close to the saturation temperature of carbon dioxide but not lower than -23° C.
Claim 2
Dependent Claim
104 words
In a process for the expansion of tobacco comprising the steps of: (1) contacting tobacco with carbon dioxide gas at a pressure of at least 250 psig for a time sufficient to impregnate the tobacco with the carbon dioxide gas to form a gaseous carbon dioxide-tobacco system, (2) releasing the pressure and (3) thereafter subjecting the carbon dioxide-treated tobacco to rapid heating conditions to remove the carbon dioxide and thereby expand the tobacco, the improvement comprising cooling the gaseous carbon dioxide and tobacco system in step (1) to a temperature close to the saturation temperature of carbon dioxide but not lower than -23° C.
Claim 3
Dependent Claim
120 words
A process for expanding tobacco to achieve at least about 50 percent increase in cylinder volume, comprising the steps of (1) impregnating tobacco with gaseous carbon dioxide under a pressure of at least about 250 psig and at sufficient temperature that substantially all of the carbon dioxide is maintained in gaseous form, (2) cooling the carbon dioxide/tobacco system while maintaining substantially all of the carbon dioxide in gaseous form, at substantially constant pressure, to bring the enthalpy of the said carbon dioxide below about 140 BTU/lb m , (3) decreasing the pressure on the carbon dioxide/tobacco system, and (4) heating the impregnated tobacco under conditions effective to liberate the carbon dioxide therein so as to cause expansion of the tobacco.
Claim 4
Dependent Claim
120 words
A process for expanding tobacco to achieve at least about 50 percent increase in cylinder volume, comprising the steps of (1) impregnating tobacco with gaseous carbon dioxide under a pressure of at least about 250 psig and at sufficient temperature that substantially all of the carbon dioxide is maintained in gaseous form, (2) cooling the carbon dioxide/tobacco system while maintaining substantially all of the carbon dioxide in gaseous form, at substantially constant pressure, to bring the enthalpy of the said carbon dioxide below about 140 BTU/lb m , (3) decreasing the pressure on the carbon dioxide/tobacco system, and (4) heating the impregnated tobacco under conditions effective to liberate the carbon dioxide therein so as to cause expansion of the tobacco.
Claim 5
Dependent Claim
17 words
The process of claim 2 wherein the pressure is reduced to substantially atmospheric pressure in step (3).
Claim 6
Dependent Claim
18 words
The process of claim 2 wherein said pressure in steps (1) and (2) is 400 to 800 psig.
Claim 7
Dependent Claim
24 words
The process of claim 2 wherein step (4) includes heating the tobacco to a temperature in the range of about 100° to 370° C.
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) | 1983-11-25 | 1984-05-26 | 1984-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-25 | 1988-05-26 | 1988-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-25 | 1992-05-26 | 1992-11-25 | $7700.00 | Window Closed / Lapsed |