Chemical heat source for use in smoking articles

• US 7,290,549 B2
• Filed: 07/22/2003
• Issued: 11/06/2007
• Est. Priority Date: 07/22/2003
• Status: Active Grant

• Current Assignee: R J Reynolds Tobacco Company (R. J. Reynolds Tobacco)
• Original Assignee: R J Reynolds Tobacco Company (R. J. Reynolds Tobacco)
• Inventors: Banerjee, Chandra Kumar, Taylor, Joanne Naomi, Cash, Sheila Lynnette, Turner, Patty Ferguson, Gentry, Thomas Leeroy
• Primary Examiner(s): MAYES, DIONNE WALLS
• Application Number:
  US10/625,762
• Publication Number:
  US 20050016549A1
• Time in Patent Office: 1,568 Days
• Field of Search: 131/194, 131/361
• US Class Current: 131/194
• CPC Class Codes: A24B 15/16 of tobacco substitutes
• CPC Class Codes: A24F 42/10 Devices with chemical heating means
• CPC Class Codes: A24F 42/60 Constructional details
• CPC Class Codes: A24F 42/80 Manufacture
• CPC Class Codes: C09K 5/18 Non-reversible chemical reactions

Abstract

A non-combustion, chemical heat source includes a heat chamber having a closed end and an open end. The heat chamber includes an apertured heat cartridge disposed at the open end of the chamber, an abutment disposed at the closed end of the chamber, an activating solution, a frangible seal separating the activating solution and the heat cartridge. The heat cartridge includes metallic agents that may come in a variety of configurations. The heat source is activated when the heat cartridge is pushed through and breaks the frangible seal allowing contact between the metallic agents and the activating solution. The heat cartridge includes an aperture in the bottom of the cartridge and absorbent paper surrounding the metallic agents, both of which control the transfer of the activating solution into the metallic agents to cause the chemical reaction. The heat sources may be incorporated into smoking articles and may also be used to heat foods or beverages, in hand warmers, and to heat equipment or materials.

Claims

1. A smoking article comprising:

tobacco; and

a chemical heat source comprising;

a heat chamber having an open end, a closed end, and a length;

an abutment having a length disposed at the closed end of the heat chamber;

a heat cartridge disposed at the open end of the heat chamber having a closed end and an end including an aperture therein;

a frangible partition disposed between the heat cartridge and the abutment; and

an activating solution disposed between the frangible partition and the closed end of the heat chamber.

2. The smoking article of claim 1 wherein the heat source is activated by pushing the heat cartridge beyond the frangible partition to release the activating solution through the aperture of the heat cartridge.

3. The smoking article of claim 2, wherein the abutment prevents the heat cartridge from penetrating the closed end of the heat chamber.

4. The smoking article of claim 2 wherein the heat cartridge reaches a temperature of at least about 100°

C. within one minute of activation and maintains a temperature of over 100°

C. for at least about five minutes.

5. The smoking article of claim 1 wherein the frangible partition is disposed a distance from the closed end of the heat chamber wherein the distance is greater than the length of the abutment.

6. The smoking article of claim 5, wherein the abutment stops the heat cartridge at a distance, equal to the length of the abutment, from the closed end of the heat chamber when the heat cartridge is pushed past the frangible partition.

7. The smoking article of claim 1, wherein the length of the abutment is between about 15% to about 20% of the length of the heat chamber.

8. The smoking article of claim 1, wherein the abutment comprises a tube.

9. The smoking article of claim 1, wherein the abutment comprises a tube fragment.

10. The smoking article of claim 9, wherein the tube fragment is comprised of a polyester film.

11. The smoking article of claim 1, wherein the heat chamber is comprised of polypropylene and wherein the heat chamber can withstand temperatures of at least about 200°

C.

12. The smoking article of claim 1, wherein the heat cartridge comprises a chemical compound capable of producing heat.

13. The smoking article of claim 12, wherein the chemical compound comprises a metallic alloy.

14. The smoking article of claim 13, wherein the metallic alloy comprises magnesium and iron.

15. The smoking article of claim 1, wherein the frangible partition comprises wax or polymeric film.

16. The smoking article of claim 1, wherein the activating solution comprises potassium chloride and potassium nitrate.

17. The smoking article of claim 1, wherein the heat chamber is surrounded by the tobacco.

18. The smoking article of claim 1, wherein the smoking article has two ends and further comprises a filter disposed at one end of the smoking article.

19. The smoking article of claim 1, wherein the tobacco is treated to reduce the volatilization temperature of the tobacco components.

20. The smoking article of claim 19, wherein the tobacco is in the form of a reconstituted tobacco sheet impregnated with a porous material.

21. The smoking article of claim 1, wherein the smoking article is a cigarette.

22. The smoking article of claim 1, wherein the smoking article is a cigar.

32. A method of heating tobacco in a smoking article, comprising:

providing the smoking article of claim 1;

pushing the heat cartridge through the frangible partition, toward the closed end of the heat chamber;

contacting the activating solution with the heat cartridge.

33. The method of claim 32, wherein the heat cartridge comprises a metallic alloy.

34. The method of claim 32, wherein the heat cartridge comprises magnesium and iron.

35. The method of claim 32, wherein the activating solution comprises potassium chloride and potassium nitrate.

36. The method of claim 32, wherein the heat cartridge reaches a temperature of at least about 100°

C. within one minute of initiating the reaction.

37. The method of claim 36, wherein the heat cartridge maintains a temperature of at least about 100°

C. for at least about five minutes.

38. The method of claim 32, wherein the frangible partition is punctured by the heat cartridge being pushed with a pushrod toward the closed end of the heat chamber.

39. The method of claim 32, further comprising allowing the heat cartridge to expand after contact with the activating solution, thereby forming a seal between the heat cartridge and the heat chamber to allow pressure to increase in the closed end of the heat chamber, whereby the pressure forces activating solution into the heat cartridge thereby maintaining increased temperatures generated by the heat source.

23. A smoking article comprising:

tobacco comprising at least one volatile flavoring agent; and

a chemical heat source comprising;

a heat chamber having an open end, a closed end, and a length;

a stopper having a length disposed at the closed end of the heat chamber;

a heat cartridge disposed at the open end of the heat chamber having a closed end and an end including an aperture therein;

a frangible partition disposed between the heat cartridge and the stopper; and

an activating solution disposed between the frangible partition and the closed end of the heat chamber.

24. The smoking article of claim 23, wherein the at least one volatile flavoring agent surrounds the heat chamber.

25. A method of heating tobacco in a smoking article, comprising:

providing a heat chamber surrounded by tobacco and having a heat cartridge disposed therein;

pushing the heat cartridge toward a closed end of the heat chamber until the heat cartridge reaches a means for stopping the cartridge a distance from the closed end;

puncturing a frangible partition, positioned a distance from the closed end of the heat chamber, whereby an activating solution is released; and

contacting the activating solution with the heat cartridge.

26. The method of claim 25, wherein the heat cartridge comprises a metallic alloy.

27. The method of claim 25, wherein the heat cartridge comprises magnesium and iron.

28. The method of claim 25, wherein the activating solution comprises potassium chloride and potassium nitrate.

29. The method of claim 25, wherein the heat cartridge reaches a temperature of at least about 100°

C. within one minute of contacting the activating solution.

30. The method of claim 29, wherein the heat cartridge maintains a temperature of at least about 100°

C. for at least about five minutes.

31. The method of claim 25, wherein the frangible partition is punctured by the heat cartridge being pushed with a pushrod toward the closed end of the heat chamber.