IE47502B1 - Process for improving the smoking properties of reconstituted tobacco and tobacco product - Google Patents

Abstract

The smoking properties of a tobacco product containing reconstituted tobacco are improved by causing both carbon and one or more alkaline earth element oxides, carbonates, bicarbonates, basic carbonates, mixed carbonates, hydroxides or alkaline earth element compounds which form oxides of such elements at or below the temperature of the burning tobacco product to be incorporated in the reconstituted tobacco so that after incorporation the weight ratio of carbon to alkaline earth element compounds is in the range from one-to-ten to ten-to- one by weight. The total amount of carbon and alkaline earth element compound is in the range from two to fifty percent, by weight, of the reconstituted tobacco. The carbon and alkaline earth compound additives may be used alone or in conjunction with other additives such as alumina, clays, calcium citrate or silicates, or diatomaceous earth.

Description

The present invention relates to the improvement of the smoking properties of tobacco products comprising shaped reconstituted tobacco material.

Additives or fillers have long been incorporated in tobacco 5 containing products to change their characteristics. For example, activited carbon has been added to increase the heat of combustion of tobacco substitutes and additions of alkaline earth salts have been suggested to provide mineralized agents (see Briskin et al United States Patent Specification No. 3,608,560).

The addition of finely-divided carbon to reconstituted tobacco has also been suggested to reduce total particulate matter in the smoke (see U.S. Hedges et al United States Patent Specification No. 3,805,803).

However, the combined use of carbon, such as activated carbon or amorphous carbon, and oxides or carbonates or bi carbonates or basic carbonates or mixed carbonates or hydroxides of an alkaline earth element or compounds which will produce such oxides as the product is burned to improve smoking properties, as an additive in reconstituted tobacco has not previously been used or suggested in the art.

The present invention provides a process for improving the mildness , and smoke taste p'roperties of a tobacco product comprising a shaped reconstituted tobacco material . comprising the step of incorporating, as defined hereinbelow, carbon having a mesh size so as to be substantially retained by said reconstituted tobacco material and one or more alkaline earth element compounds selected from oxides, bi carbonates, basic carbonates, hydroxides and alkaline earth element compounds which form oxides of such elements under temperature conditions existing in a burning tobacco product, into the reconstituted tobacco material, the ratio by weight of carbon to said one or more compounds in the product being in the range from one-to-ten to ten-to-one and the percentage of the total weight of carbon and the alkaline earth element compounds being from 2 to 50% of the total weight of said tobacco product.

In another aspect the present invention provides a tobacco product comprising a shaped reconstituted tobacco material characterized in that the reconstituted tobacco material contains carbon having a mesh size so as to be substantially retained by said reconstituted tobacco material and one or more alkaline earth element compounds selected from oxides, bicarbonates, basic carbonates, hydroxides and other alkaline earth element compounds which form oxides of such elements under temperature conditions existing in a burning tobacco product, the ratio by weight of the carbon to said one or more compounds in the reconstituted tobacco material being in the range from one-to-ten to ten-to-one and the percentage of the total weight of carbon and the alkaline earth element compound(s) being from 2 to 50 percent of total weight of said tobacco product.

As used herein the expression incorporating into the tobacco material includes the additives (including one or more of the carbon and the alkaline earth element compound(s) and any other additives that may be employed) being formed in situ or applied to the reconstituted tobacco material during or after it is shaped into the tobacco product.

In another aspect the invention provides an improved tobacco product when made by the process of the invention.

Carbon of varying particulate sizes may be used in the present invention. For example, activated carbon made by the Witco Chemical Company having a screen distribution of +80 mesh ASTM (American Society for Testing and Material^, 0.4%; 80 to 325 mesh ASTM, 87.4% and passing through 325 mesh ASTM, 12%, may be used. Also, large surface area carbon particles whether or not considered by the art to be activated, may be used. In general carbon particles of any size may be used provided the carbon can be substantially retained by the reconstituted tobacco during its manufacture and subsequent processing The carbon particles may be mixed with other ingredients and readily incorporated into or applied to the reconstituted tobacco product.

With respect to the alkaline earth element compounds it has been found that magnesium carbonate, basic magnesium carbonate, magnesium hydroxide, magnesium oxide, calcium oxide and calcium hydroxide give good results. Magnesium citrate may also be used since it forms oxides of magnesium under the temperature conditions of the turning of the product thus providing in situ the desired additive.

As contemplated by this invention, the alkaline earth elements include magnesium, calcium and strontium.

In one embodiment, the carbon and the alkaline earth element compound are admixed in any suitable container. To this mixture may also be added other additives such as alumina, clays (aluminium silicates), *CELITE (diatomaceous earth), *H1-S1L (hydrated amorphous silicates) and *Micro-Cel (Hydrated calcium silicates) *CELITE, *H1-S1L and Micro-Cel are all trade marks.

For a reconstituted tobacco material made by the papermaking or Fourdrinier process, the additives or fillers may be incorporated into the base sheet or other shape of the material by mixing the additives with the tobacco prior to or after the refining operation or the additives may be suspended in a water slurry which is added to the refined tobacco at the fan pump of the Fourdrinier machine.

An alternative method, is to suspend the additives in the tobacco water extract and to apply them to the base sheet at the size press.

If the reconstituted tobacco is made by the cast film technique, the additives may be incorporated with the pulverized or refined tobaccos and then processed in the usual manner.

In another embodiment, carbon and the alkaline earth element compounds are added separately during manufacture of the shaped material or applied separately to the material after it has been shaped.

The alkaline earth element compounds may also be formed in situ in the tobacco material by adding the elements and/or other consitutuents of the compound during or after manufacture of the tobacco material and then converting them in situ to the desired alkaline earth element compounds.

EXAMPLE A blend of tobaccos was water extracted to separate the water soluble portion from the fibre. The extracted tobacco fibre was refined to a C.S. Freeness of approximately 200 millimetres. A water slurry of the additives (activated carbon, magnesium carbonate and alumina) was made and added to the refined tobacco stock in the head box of the paper machine to form the base sheet. The tobacco-water extract 47S02 was then applied to the base sheet. The base sheet following application of the tobacco-water extraction was found to have the approximate following percentage composition by weight (calculations made on a moisture-free basis): Tobacco blend 75% Activiated charcoal 5% Magnesium carbonate 5% Alumina 15% 100% Cigarettes made from the cut sheet are milder and have superior smoke taste as compared with a control made in a similar manner but not containing carbon and magnesium carbonate. Similar improvement was also realized when no alumina was added to the above formulation.

The combination of additives markedly improves the smoke taste and sidestream of the reconstituted tobacco containing product making it very superior to that obtained when the additives are used individually. The stemmy character of the smoke taste is reduced and unexpectedly the tobacco character is increased. A similar effect is also noted on the sidestream aroma of a cigarette made with this product. As an example of the effect smokers can usually take only one or two puffs of a cigarette made with unmodified reconstituted tobacco; however, they can comfortably smoke the whole cigarette made according to the above example. Further, the use of additives in the reconstituted tobacco reduces the amount of combustion products: tars that are formed when the product is burned.

The amount of carbon and alkaline earth element compound in the finished product to effect the improvement in smoking properties should be 2 to 50% and preferably, 5-15%, by weight.

Claims (23)

1. A process for improving the mildness and smoke taste properties of a tobacco product comprising a shaped reconsituted tobacco material comprising the step of incorporating, as defined hereinbefore, carbon having a mesh size so as to be substantially retained by said reconstituted tobacco material and one or more alkaline earth element compounds selected from oxides, bicarbonates, basic carbonates, hydroxides and alkaline earth element compounds which form oxides of such elements under temperature conditions existing in a burning tobacco product, into the reconstituted tobacco material, the ratio by weight of carbon to said one or more compounds in the product being in the range from one-to-ten to ten-to-one and the percentage of the total weight of carbon and the alkaline earth element compounds being from 2 to 50% of the total weight of said tobacco product.

2. A process according to Claim 1 in which the total weight of carbon and said compound(s) is from 5 to 15% of the total weight of the tobacco product.

3. A process according to Claim 1 or Claim 2, wherein the reconstituted tobacco material is made from a slurry.

4. A process according to Claim 3 in which the carbon and the alkaline earth element compound(s) are added to the slurry used in making the reconstituted tobacco material.

5. A process according to Claim 4 in which incorporation of said alkaline earth element compound(s) is effected by the incorporation of the constituents of said alkaline earth element compound into said slurry, said constituents being converted in situ into said 4 7 5 Ο 2 alkaline earth element compound prior to burning of the reconsituted tobacco material.

6. A process according to any one of Claims 1 to 4, in which an alkaline earth element compound which forms an alkaline earth 5 element oxide during smoking of the tobacco material is incorporated into the reconstituted tobacco material.

7. A process according to any one of Claims 1 to 3, in which the carbon and the alkaline earth element compound(s) are incorporated into the reconstituted tobacco material after it has been formed into 10 a shape.

8. A process according to any one of Claims 1 to 4 and 6, in which the carbon and the alkaline earth element compound(s) are mixed together before incorporation thereof into the reconstituted tobacco material. 15

9. A process according to any one of Claims 1 to 8, in which activated carbon and magnesium carbonate mixed together in a ratio of one-to-one by weight are incorporated into the reconstituted tobacco material.

10. A process according to any one of Claims 1 to 9, in which 20 activated carbon and magnesium oxide mixed together are incorporated into the reconstituted tobacco material.

11. A process according to any one of Claims 1 to 10, in which activated carbon and calcium carbonate mixed together are incorporated into the reconstituted tobacco material. 4 7 S Ο 3

12. A process according to any one of Claims 1 to 11, in which activated carbon and calcium oxide mixed together are incorporated into the reconstituted tobacco material.

13. A process according to any one of Claims 1 to 12, in which carbon and magnesium citrate mixed together are incorporated into the reconstituted tobacco material.

14. A process for improving the mildness and smoke taste properties of a tobacco product according to Claim 1, substantially as described hereinbefore with particular reference to the Examples.

15. A tobacco product when made by a process according to any one of the preceding claims.

16. A tobacco product comprising a shaped reconstituted tobacco material characterized in that the reconstituted tobacco material contains carbon having a mesh size so as to be substantially retained by said reconstituted tobacco material and one or more alkaline earth element compounds selected from oxides, bi carbonates, basic carbonates, hydroxides and other alkaline earth element compounds which form oxides of such elements under temperature conditions existing in a burning tobacco product, the ratio by weight of the carbon to said one or more compounds in the reconstituted tobacco material being in the range from one-to-ten to ten-to-one and the percentage of the total weight of carbon and the alkaline earth element compound(s) being from 2 to 50 percent of total weight of said tobacco product. 4 7 5 0 2

17. A product according to Claim 16 in which the total weight of carbon and said compounds is from 5 to 15% of the total weight of the tobacco product.

18. A product according to Claim 16 or Claim 17, in which 5 the tobacco material contains activated carbon and magnesium carbonate in a ratio of one-to-one by weight.

19. A product according to any one of Claims 16 to 18, in which the tobacco material contains activated carbon and magnesium oxide.

20. A product according to any one of Claims 16 to 19, in 10 which the tobacco material contains activated carbon and calcium carbonate.

21. A product according to any one of Claims 16 to 20, in which the tobacco material contains activated carbon and calcium oxide.

22. A product according to any one of Claims 16 to 21, in which 15 the tobacco material contains carbon and magnesium citrate.

23. A tobacco product according to Claim 16, substantially as described hereinbefore with particular reference to the Example .