WO2013170028A1

WO2013170028A1 - Tobacco product that produces lower carbon monoxide to tar ratio

Info

Publication number: WO2013170028A1
Application number: PCT/US2013/040348
Authority: WO
Inventors: Lanig Le Bec; Stephane ROUILLARD; Jerome ACCOU; Peter BRIGHENTI
Original assignee: Lanig Le Bec; Rouillard Stephane; Accou Jerome; Brighenti Peter
Priority date: 2012-05-09
Filing date: 2013-05-09
Publication date: 2013-11-14
Also published as: EP2846651A1; CN104486955B; CN104486955A; EP2846651B1

Abstract

A reconstituted tobacco product is disclosed that can be used to produce smoking articles having lower carbon monoxide levels and carbon monoxide to tar ratios. The reconstituted tobacco material contains a polymer component and a burn retardant. The polymer component forms a coating on the surface of the reconstituted tobacco sheet. The burn retardant can be incorporated into the tobacco material or combined with the polymer component and contained in the coating.

Description

TOBACCO PRODUCT THAT PRODUCES LOWER

CARBON MONOXIDE TO TAR RATIO

RELATED APPLICATIONS

The present application is based upon and claims priority to U.S.

Provisional Patent Application Serial No. 61/644,775 filed on May 9, 2012, and which is incorporated herein by reference.

BACKGROUND

Smoking articles, such as cigarettes, are conventionally made by wrapping a column of tobacco in a wrapping paper. At one end, the smoking article usually includes a filter through which the article is smoked. Filters are attached to smoking articles using a tipping paper that is glued to the wrapping paper. When the article is smoked, mainstream smoke is generated that is inhaled through the filter. Mainstream smoke can contain numerous components that provide the smoking article with a particular taste, which encompasses the sensations detected not only by one's taste, but also by one's sense of smell.

Many attempts have been made in the past to reduce certain components or constituents that may be contained in the mainstream smoke of a smoking article. For instance, in the relatively recent past, extensive research has been conducted on reducing Hoffmann analytes in the mainstream smoke. One Hoffmann analyte that those skilled in the art have attempted to reduce from mainstream smoke is carbon monoxide. In fact, a need currently exists for a method for reducing carbon monoxide in mainstream smoke in order to meet present or future government regulations.

In the past, various attempts to reduce carbon monoxide levels in the mainstream smoke of a cigarette have centered around diluting the mainstream smoke with air or through the cigarette paper. For instance, in order to dilute the mainstream smoke, wrapping papers for cigarettes have been perforated or otherwise constructed so as to increase air porosity. Filters have also been designed to allow ventilating air to mix with the mainstream smoke prior to exiting the filter. Cigarette paper design can also be adjusted in order to reduce further mainstream carbon monoxide.

Although the above methods can, in some applications, lower carbon monoxide levels in cigarettes, further improvements in lowering carbon monoxide levels are still needed. Many prior methods simply do not lower carbon monoxide levels to a desired extent, especially in view of present or impending government regulations. Thus, a need currently exists for an improved method of reducing carbon monoxide levels, and particularly for reducing the carbon monoxide to tar ratio.

SUMMARY

The present disclosure is generally directed to a treatment for reducing the carbon monoxide and the carbon monoxide to tar ratio of a smoking article. In particular, according to the present disclosure, a reconstituted tobacco product is produced that may be blended with standard tobacco leaf to produce a smokable rod for use in smoking articles such as cigarettes. By incorporating, for instance, the reconstituted tobacco product into the smokable rod in an amount of about 30% by weight, the carbon monoxide to tar ratio can be reduced by greater than 5%, such as greater than about 8%, such as even greater than about 10% compared to the same smokable rod with the same amount of reconstituted tobacco not treated in accordance with the disclosure.

In order to reduce the carbon monoxide to tar ratio as described above, a tobacco material is combined with a treatment that includes a burn retardant, a polymer component, and optionally filler particles. The burn retardant may comprise, for instance, a carbonate or a phosphate salt. The carbonate or phosphate salt, for instance, may comprise an alkali metal salt, such as a potassium salt or a sodium salt. In an alternative embodiment, the burn retardant may comprise an ammonium salt.

The polymer component, on the other hand, may comprise a film former. The polymer component may comprise, for instance, guar gum, pectin, polyvinyl alcohol, a cellulose derivative, alginate, starch, a starch derivative, or mixtures thereof.

The amount each component is added to the tobacco material can depend upon various factors. In general, the burn retardant is added in an amount from about 0.1 % to about 20% by weight, such as in an amount from about 5% to about 15% by weight. The polymer component, on the other hand, may be added in an amount from about 0.1 % to about 10% by weight, such as from about 0.5% to about 5% by weight, such as from about 0.5% to about 3% by weight. It has been discovered that the combination of a burn retardant with a polymer component can significantly reduce a carbon monoxide to tar ratio when the tobacco material is smoked.

The reconstituted tobacco product comprises a tobacco material containing refined tobacco stems and fines.

Prior to or during refining of the tobacco material, the tobacco material is combined with an aqueous solution at an elevated temperature. Water soluble components contained in the tobacco material become dissolved within the solution to produce a tobacco soluble fraction. At least a portion of the solubles is then removed from the tobacco material.

The tobacco material described above can optionally be recombined with the tobacco soluble fraction. The tobacco soluble fraction may be added to the tobacco material such that the soluble fraction is present in the reconstituted tobacco product in an amount generally from about 5% to about 50% by weight.

The treatment of the present disclosure can be added to the tobacco material at various points in the process of making the reconstituted tobacco product. In one embodiment, for instance, the burn retardant and polymer component are combined together and applied to the tobacco material either after the tobacco material has been combined with the soluble fraction or before the tobacco material has been combined with the soluble fraction. In an alternative embodiment, the burn retardant and the polymer component are added separately. For example, in one embodiment, the burn retardant may be added to the tobacco material prior to combining the tobacco material with the soluble fraction or may be added to the tobacco material with the soluble fraction. The polymer component may then be added after the soluable fraction has been combined with the tobacco material.

In one embodiment, the polymer component (optionally together with the burn retardant) may be applied to the tobacco material as a coating. As used herein, a coating comprises a covering or layer applied to a substrate.

The above described reconstituted tobacco product can then be used to produce a smoking article, such as a cigarette. In one embodiment, for instance, the reconstituted tobacco may be used alone or in combination with tobacco leaf products to produce a smokable rod. For instance, the smokable rod may comprise from about 10% by weight to about 70% by weight of the reconstituted tobacco product, such as from about 15% to about 50% by weight of the reconstituted tobacco product. The smokable rod can be surrounded by a wrapping paper and can include a filter at one end.

Other features and aspects of the present disclosure are discussed in greater detail below.

Brief Description of the Drawings

A full and enabling disclosure of the present invention, including the best mode thereof to one skilled in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:

Fig. 1 is a perspective view of a smoking article made in accordance with the present invention; and

Fig. 2 is an exploded view of the smoking article illustrated in Fig. 1 .

Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention.

DETAILED DESCRIPTION

It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention.

In general, the present disclosure is directed to a reconstituted tobacco product that, when incorporated into a smoking article, can dramatically reduce carbon monoxide gas in the mainstream smoke when compared to other components, such as tar. In order to produce a reconstituted tobacco product in accordance with the present disclosure, a tobacco material is combined with a polymer component, and optionally a burn retardant and/or one or more fillers. It has been discovered that coating on a tobacco material a polymer component optionally in combination with a burn retardant can dramatically reduce carbon monoxide levels in relation to tar when the tobacco material is incorporated into a smoking article, such as a cigarette.

In one embodiment, the polymer component, with or without the burn retardant, is in the form of a coating on the reconstituted tobacco product. The coating can be present on one side of the reconstituted tobacco sheet or can be present on both sides of the reconstituted tobacco sheet. The coating can be present as a film on the surface of the reconstituted tobacco sheet and can be continuous or discontinuous. In one embodiment, the coating contains both the polymer component and the burn retardant. In an alternative embodiment, the coating only contains the polymer component. In this embodiment, the burn retardant may optionally be incorporated into the reconstituted tobacco product prior to formation of the coating.

When producing the reconstituted tobacco product, a tobacco material is contacted with an aqueous solution at elevated temperatures to produce a fraction containing solubles. The tobacco soluble fraction can then be separated from the tobacco material. The tobacco soluble fraction may optionally be recombined with the tobacco material during production of the reconstituted tobacco product. In accordance with the present disclosure, the burn retardant and the polymer component can be combined with the tobacco material during the above described process. In one embodiment, both materials are added independently of recombining the tobacco material with the tobacco soluble fraction.

For example, in one embodiment, before but preferably after the tobacco soluble fraction has been recombined with the tobacco material, the burn retardant and the polymer component may be combined together and applied to the tobacco material. In one particular embodiment, for instance, the burn retardant and the polymer component are applied together or separately after the tobacco material has been recombined with the tobacco soluble fraction.

The polymer component forms a coating on the reconstituted tobacco material or sheet as opposed to impregnating the material or sheet. In order to form a coating, the polymer component can be applied to the reconstituted tobacco sheet after the sheet has been at least partially dried. For instance, the reconstituted tobacco sheet can have a moisture content of less than about 50% by weight, such as less than about 30% by weight, such as less than about 20% by weight, such as less than about 15% by weight when the polymer component is applied to the surface of the reconstituted tobacco sheet. In one embodiment, for instance, the reconstituted tobacco sheet can be completely dry and have a moisture content of less than 10%. As used herein, a reconstituted tobacco sheet refers to any web of material made from the tobacco fibers and may include or may not include the soluble fraction. The polymer component can be applied to the reconstituted tobacco sheet using any suitable coating equipment. For instance, the coating can be formed by printing, or any suitable roll-to-roll method. Roll-to-roll coating methods include air knife coating, curtain coating, flexographic coating, knife over roll coating, Meyer Bar coating, reverse roll coating, and the like. Once the polymer component is applied to a surface of the reconstituted tobacco sheet, the coating can be dried. In one embodiment, a coating may be formed on a first side of the reconstituted tobacco sheet and dried and then subsequently applied to a second and opposite side of the reconstituted tobacco sheet and dried. Alternatively, both sides of the

reconstituted tobacco sheet may be simultaneously coated. In another embodiment, only a single side of the reconstituted tobacco sheet may be coated with the polymer component.

It has been discovered that when the polymer component forms a coating on the reconstituted tobacco product, carbon monoxide levels are dramatically reduced. A burn retardant may optionally be incorporated into the product for further reducing carbon monoxide levels. The burn retardant can be incorporated into the reconstituted tobacco product prior to formation of the coating made from the polymer component. Alternatively in a preferred embodiment, the burn retardant may be combined with the polymer component and incorporated into the coating that is formed on the reconstituted tobacco.

The burn retardant generally comprises a salt, such as a salt of a carbonate or a phosphate. The polymer component, on the other hand, may comprise a film former. In one embodiment, the polymer component comprises starch or a starch derivative.

The present inventors discovered that the above process can lead to a reconstituted tobacco product that produces significantly less carbon monoxide gas in the mainstream smoke in comparison to tar. For example, when combined with a tobacco blend to produce a smokable rod such that the reconstituted tobacco product of the present disclosure is contained in the rod in an amount less than about 70% by weight, such as in an amount less than 60% by weight, such as in an amount less than 50% by weight, such as even in an amount less than about 40% by weight, a smoking article or cigarette can have a carbon monoxide to tar ratio that is at least about 5%, such as at least about 10%, such as even about 15% less in comparison to a smoking article or cigarette

containing a conventional reconstituted tobacco product. The above carbon monoxide to tar ratio reduction can be achieved in a standard cigarette having a tobacco weight of 900 milligrams and a hardness of 1 .2 mm. The cigarette can also produce a puff count of from about 7.5 to about 8.5, such as from about 8.0 to about 8.5 (as measured on a standard smoking machine such as a Borgwaldt RM20 kit) especially when using an American blend tobacco product.

The reconstituted tobacco product of the present disclosure can be combined with any suitable tobacco blend to produce a smoking article such as a cigarette. The tobacco blend, for instance, may comprise an American blend, an Oriental blend, a Virginia blend, or the like.

In one embodiment, for example, a tobacco furnish containing tobacco stems (e.g., flue-cured stems), fines and/or other tobacco by-products from tobacco manufacturing processes is initially mixed with a solvent (e.g., water and/or other compounds). Various solvents that are water-miscible, such as alcohols (e.g., ethanol), can be combined with water to form an aqueous solvent. The water content of the aqueous solvent can, in some instances, be greater than 50 wt.% of the solvent, and particularly greater than 90 wt.% of the solvent.

Deionized water, distilled water or tap water may be employed. The amount of the solvent in the suspension can vary widely, but is generally added in an amount from about 50 wt.% to about 99 wt.%, in some embodiments from about 60 wt.% to about 95 wt.%, and in some embodiments, from about 75 wt.% to about 90 wt.% of the suspension. However, the amount of solvent can vary with the nature of the solvent, the temperature at which the extraction is to be carried out, and the type of tobacco furnish.

After forming the solvent/tobacco furnish mixture, some or all of a soluable fraction of the furnish mixture may be optionally separated from the mixture. The aqueous solvent/tobacco furnish mixture can be agitated by stirring, shaking or otherwise mixing the mixture in order to increase the rate of solubilization. Typically, the process is carried out for about one-half hour to about 6 hours.

Process temperatures may range from about 10°C to about 100°C.

Once the soluble fraction is separated from the tobacco furnish or insoluble fraction, the soluble fraction can be concentrated. The soluble fraction can be concentrated using any known type of concentrator, such as a vacuum evaporator. In one embodiment of the present disclosure, the soluble fraction can be highly concentrated.

The resulting blended soluble fraction or tobacco soluble fraction may be used alone as a tobacco product (e.g., flavoring material) or it may be

subsequently combined with other materials to form the tobacco product.

In one embodiment, the soluble fraction may be recombined with an insoluble fraction (e.g., sheet, tobacco blend, insoluble residue, etc.) using various application methods, such as spraying, using sizing rollers, saturating,

impregnating (such as by using a size press), etc. For example, the insoluble fraction may be subjected to one or more mechanical refiners to produce a fibrous pulp. Some examples of suitable refiners can include disc refiners, conical refiners, etc. For instance, the tobacco material may be refined such that the tobacco material has a freeness index of at least about 30° SR, such as from about 30° SR to about 60° SR.

The pulp from the refiner can then be transferred to a papermaking station that includes a forming apparatus, which may include, for example, a forming wire, gravity drain, suction drain, felt press, Yankee dryer, drum dryers, etc. In such a forming apparatus, the pulp is laid onto a wire belt forming a sheet-like shape and excess water is removed by the gravity drain and suction drain and presses.

Regardless, when recombined with the tobacco soluble fraction, the resulting tobacco product is generally known as "reconstituted tobacco."

Reconstituted tobacco can generally be formed in a variety of ways. For instance, in one embodiment, band casting can be utilized to form the

reconstituted tobacco. Band casting typically employs a slurry of finely divided tobacco parts and a binder that is coated onto a steel band and then dried. After drying, the sheet is blended with natural tobacco strips or shredded and used in various tobacco products, including as a cigarette filler. Some examples of process for producing reconstituted tobacco are described in U.S. Patent Nos. 3,353,541 ; 3,420,241 ; 3,386,449; 3,760,815; and 4,674,519; which are

incorporated herein in their entirety by reference thereto for all relevant purposes. Reconstituted tobacco can also be formed by a papermaking process. Some examples of processes for forming reconstituted tobacco according to this process are described in U.S. Pat. Nos. 3,428,053; 3,415,253; 3,561 ,451 ; 3,467,109;

3,483,874; 3,860,012; 3,847,164; 4,182,349; 5,715,844; 5,724,998; and 5,765,570; which are also incorporated herein in their entirety by reference thereto for all relevant purposes. For example, the formation of reconstituted tobacco using papermaking techniques can involve the steps of mixing tobacco with water, separating the soluble fraction therefrom, concentrating the soluble fraction, refining the tobacco, forming a web, reapplying the concentrated soluble fraction, drying, and threshing.

In accordance with the present disclosure, a burn retardant and a polymer component are combined with the tobacco material during production of the reconstituted tobacco product. The burn retardant and the polymer component may be first combined together and applied to the tobacco material or may be applied to the tobacco material independently of each other. Although each of the additives may be combined with the soluble fraction and then applied to the tobacco material, preferably both additives are either applied before or after the tobacco material is recombined with the soluble fraction.

In one preferred embodiment, the polymer component forms a coating on the tobacco material after the soluble fraction has been applied to the tobacco material (if it is desired to combine the soluble fraction with the tobacco material). The burn retardant can be applied to the tobacco material by itself or it can be combined with the polymer component and incorporated into the coating.

The burn retardant may generally comprise any suitable burn retardant salt. In one embodiment, for instance, the burn retardant may comprise a carbonate or a phosphate. For instance, the burn retardant may comprise an alkali metal salt of a phosphate or a carbonate or may comprise an ammonium salt of a phosphate. Particular examples of burn retardants that may be used include sodium

carbonate, potassium carbonate, sodium dihydrogen phosphate, potassium dihydrogen phosphate, diammonium phosphate, and mixtures thereof. The amount of burn retardant combined with the tobacco material can vary depending upon the particular application. In general, the burn retardant is applied to the tobacco material in an amount of from about 0.1 % to about 20% by weight. In general, the burn retardant is added in amounts greater than about 5% by weight, such as in amounts greater than about 7% by weight, such as in amounts greater than about 10% by weight. In general, the burn retardant is added in an amount less than about 15% by weight, such as in an amount less than about 12% by weight, such as in an amount less than 10% by weight.

The polymer component, on the other hand, may comprise a film former, which may also be referred to as a film-forming material. The polymer component, for instance, may comprise guar gum, pectin, polyvinyl alcohol, a cellulose derivative, alginate, a starch, a starch derivative, or mixtures thereof. The amount of polymer component added to the tobacco material can depend upon various factors including the end use application and the particular burn retardant being used. In general, the polymer component is added in an amount from about 0.1 % to about 10% by weight. For example, the polymer component can be added in an amount less than about 8% by weight, such as in an amount less than about 5% by weight, such as in an amount less than about 4% by weight. The polymer component is generally present in an amount greater than about 0.5% by weight, such as in an amount greater than about 1 % by weight.

Although the polymer component and the burn retardant may be added at any suitable step during the process of making the reconstituted tobacco, in one embodiment, the polymer component is added after the tobacco material has been formed into a sheet. The polymer component can be added and coated onto the sheet alone or in combination with the burn retardant. When applied to the sheet, any suitable device may be used in order to deposit the material onto the sheet. A printer, or any suitable apparatus may be used. The coating can form a film on the surface of the reconstituted tobacco sheet. The coating can be present on only a single side of the reconstituted tobacco sheet or it can be applied to both sides of the reconstituted tobacco sheet.

The burn retardant as described above may be combined with the polymer component and applied to the tobacco material or may be applied independently. When applied independently, the burn retardant may be added prior to recombining the tobacco material with the soluble fraction or after combining the tobacco material with the soluble fraction. Although the burn retardant may be combined with the soluble fraction and applied to the tobacco material, there is some possibility that the burn retardant may unfavorably react with the soluble fraction. Thus, it is preferred that the burn retardant be added independently of the soluble fraction.

In addition to the above, filler particles may also be added to the tobacco material with the polymer component. The filler particles may comprise, for instance, clay particles, calcium carbonate particles, titanium oxide particles, magnesium oxide particles, mica, kaolin clay, or mixtures thereof. When present, the filler particles are generally added in an amount less than about 5% by weight, such as in an amount less than about 3% by weight.

In addition, various other ingredients, such as flavor, can also be applied to the web. If applied with the soluble fraction and/or other ingredients, the fibrous sheet material can, in some embodiments, then be dried using, for example, a tunnel dryer, to provide a sheet having a typical moisture content of less than 20% by weight, and particularly from about 9% to about 14% by weight. Subsequently, the sheet can be cut to a desired size and/or shape and dried to the desired final moisture content.

Significantly improved tobacco products may be formed from the

reconstituted tobacco product in accordance with the present invention. As used herein, the term "tobacco product" is meant to encompass smoking articles (e.g., cigarettes, cigars, fine cut smoking articles, pipes, etc.). For illustrative purposes only, one such smoking article is shown in Figs. 1 -2. As shown, the smoking article 10 includes a smokable column 12. The smoking article 10 may also include a wrapper 14 that defines an outer circumferential surface 16 when wrapped around the smokable column 12. The article 10 may also include a filter 26 that may be enclosed by a tipping paper. The wrapper may be made from cellulosic fibers and a filler, as is well known in the art.

In accordance with the present disclosure, the smokable column 12 can be made entirely from the reconstituted tobacco product of the present disclosure or may comprise a combination of the reconstituted tobacco product with other tobacco material. In one embodiment, for instance, the reconstituted tobacco product may be combined with a standard tobacco blend made from finely cut tobacco leaves. The tobacco blend may primarily comprise flue-cured bright leaf, burley tobacco and/or oriental tobacco. In one embodiment, the reconstituted tobacco product may be contained in the smokable column in an amount from about 10% to about 70% by weight, such as in an amount from about 15% to about 50% by weight. As described above, the presence of the novel reconstituted tobacco product can dramatically improve and reduce the carbon monoxide to tar ratio.

The present disclosure may be better understood with reference to the following examples.

EXAMPLE 1

The following example demonstrates some of the advantages and benefits of the present disclosure.

In order to produce reconstituted tobacco, the following process was generally used.

A mixture of threshed tobacco stems and tobacco scraps was initially mixed with an aqueous solution. This was followed by an extraction step in an hydraulic press to separate the aqueous portion from the tobacco fiber portion. The recovered tobacco fiber portion was again dispersed in an aqueous solution. After an additional extraction (by pressing), wood pulp was added to the tobacco fibrous residue. These samples were then refined in a beater. The resultant stock was used to make sheets. An aqueous portion was concentrated in an evaporator and then impregnated into the sheet. The impregnated sheets were then dried.

Fourteen different samples were made and tested in this example. In

Samples 1 -8, the reconstituted tobacco was produced on a commercial production machine. The samples, except for sample No. 1 , were then coated in the laboratory using a lab coater with a polymer component alone or in combination with one or more burn retardants. In Sample Nos. 2-8, the polymer component and the burn retardants were combined together and applied to the reconstituted tobacco sheet after the soluble fraction was applied to the sheet. The following summarizes Sample Nos. 1 -8. Table 1

1 2 3 4 5 6 7 8

Starch (wt%) - 1 .6 2.6 2.7 2.6 2.9 3.5 2.8

K₂C0₃ (wt%) - 4.8 - 4.1 7.6

K₃P0₄ (wt%) - - 7.8 4.1 - 8.7 -

CaC0₃ (wt%) - - - - 3.8 4.4 - 1 1 .5

In Sample Nos. 9-14 below, the reconstituted tobacco product was produced on a laboratory pilot line. In Sample Nos. 10-14, one or more burn retardants were added to the soluble fraction and applied to the sheet. The polymer component and optionally calcium carbonate were then applied as a coating after the soluble fraction had been applied to the sheet. A summary of Sample Nos. 9-14 is shown below. Table 2

9 10 11 12 13 14

K₂C0₃ (wt%) - 7.9 7.9 - - 6.3

K₃P0₄ (wt%) - - - 7.3 7.3 1 .7

Coating

Starch (wt%) - 3.9 2.4 3.9 2.4 3.9

CaC0₃ wt%) - - 7.2 - 7.2

The sheets were shredded and formed into cigarettes containing 30% by weight of the shredded reconstituted tobacco. A commercial tobacco blend was used in this example. The hand-made cigarettes were made using filtered cigarette tubes with the same hardness and tobacco weight. The hardness was 1 .5 millimeters. The tobacco weight was 850 milligrams. The cigarettes were smoked on a Borgwaldt RM20 kit smoking machine. An analysis of the smoke for each of the cigarette samples gave the following results for tar, nicotine and carbon monoxide using the ISO smoking regime:

CO/tar

Tar Nicotine CO

Sample CO/tar change vs.

(mg/cig) (mg/cig) (mg/cig)

control

1 12.3 0.88 13.7 1.12 -

2 10.5 0.78 10.4 0.99 -11 %

3 11.3 0.8 12.7 1.12 1%

4 10.9 0.8 11.8 1.08 -3%

5 10.1 0.74 10.1 1 -11 %

6 10.4 0.73 12.1 1.17 5%

7 12.1 0.87 12.7 1.05 -6%

8 10.9 0.76 12.2 1.12 0%

9 11.8 0.84 13.7 1.16 -

10 11.1 0.79 11.6 1.04 -10%

11 11.8 0.83 12.8 1.08 -7%

12 11.8 0.84 12.2 1.03 -11 %

13 10.9 0.71 12.2 1.12 -4%

14 10.7 0.7 12.3 1.15 -1%

As shown above, reconstituted tobacco made in accordance with the present disclosure can significantly reduce carbon monoxide and CO/tar ratio. As also shown above, introducing the burn retardant with the solubles is generally not as effective as adding the burn retardant after the solubles have been incorporated into the sheet by coating. EXAMPLE 2

The procedure of Example 1 was repeated. In particular, Control Sample No. 1 and Sample No. 2 were produced. Sample No. 2 included reconstituted tobacco coated with a combination of starch and potassium carbonate. The starch was present in the reconstituted tobacco in an amount of 1 .6% by weight, while the potassium carbonate was present in the tobacco material in an amount of 4.8% by weight.

Cigarettes were made as described above containing 30% by weight of the reconstituted tobacco or containing 15% by weight of the reconstituted tobacco. The following results were obtained when the reconstituted tobacco product was contained in the cigarette in an amount of 30% by weight.

TABLE 1

Puff Tar Nicotine CO CO/tar

Sample 1 7.3 12.3 mg/cig 0.88 mg/cig 13.7 mg/cig 1 .12

Sample 2 8.1 10.5 mg/cig 0.78 mg/cig 10.4 mg/cig 0.99

Difference 12% -14% -10% -24% -1 1 .2%

The following results were obtained when the reconstituted tobacco product was contained in the cigarette in an amount of 15% by weight.

TABLE 2

Puff Tar Nicotine CO CO/tar

Sample 1 7.8 13.5 mg/cig 1 .00 mg/cig 14.3 mg/cig 1 .06

Sample 2 8.3 12.7 mg/cig 0.92 mg/cig 12.4 mg/cig 0.98

Difference 6% -6% -8% -13% -7.9%

As shown above, the presence of the reconstituted tobacco product of the present disclosure produces higher puff numbers, lower tar yields and nicotine yields. The reconstituted tobacco product also significantly lowers carbon monoxide and the carbon monoxide to tar ratio.

These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention so further described in such appended claims.

Claims

What Is Claimed:

1 . A tobacco product comprising:

a reconstituted tobacco material comprising tobacco stems and fines;

a tobacco soluble fraction optionally combined with the tobacco stems and fines;

a coating on the reconstituted tobacco material, the coating comprising a polymer component, the reconstituted tobacco material further optionally

containing a burn retardant.

2. A tobacco product as defined in claim 1 , wherein the polymer component is non-fibrous.

3. A tobacco product as defined in claim 1 or 2, wherein a burn retardant is contained in the tobacco product and comprises a carbonate, a phosphate, or mixtures thereof.

4. A tobacco product as defined in claim 3, wherein the burn retardant comprises an alkali metal salt or an ammonium salt of a carbonate or a phosphate.

5. A tobacco product as defined in any of the preceding claims, wherein the burn retardant is present in an amount from about 0.1 % to about 20% by weight, and the polymer component is present in an amount from about 0.1 % to about 10% by weight.

6. A tobacco product as defined in any of the preceding claims, wherein the burn retardant is present in an amount from about 5% to about 10% by weight, and the polymer component is present in an amount from about 0.5% to about 5% by weight.

7. A tobacco product as defined in any of the preceding claims, wherein the polymer component and the burn retardant are combined together and applied to the reconstituted tobacco material.

8. A tobacco product as defined in any of the preceding claims, wherein the polymer component comprises guar gum, pectin, polyvinyl alcohol, a cellulose derivative, alginate, starch, a starch derivative, or mixtures thereof.

9. A tobacco product as defined in any of the preceding claims, or in the polymer component comprises starch or a starch derivative.

10. A tobacco product as defined in any of the preceding claims, wherein a burn retardant has been applied to the reconstituted tobacco material prior to forming the coating.

1 1 . A tobacco product as defined in any of the preceding claims, wherein the reconstituted tobacco material comprises a reconstituted tobacco sheet having a first side and a second side and wherein the reconstituted tobacco sheet is only coated on one side with the polymer component.

12. A tobacco product as defined in any of the preceding claims, wherein the reconstituted tobacco material comprises a reconstituted tobacco sheet having a first side and a second side and wherein the tobacco sheet has been coated on the first side and the second side with the polymer component.

13. A smoking article comprising a smokable rod containing from about 10% by weight to about 70% by weight, such as from about 15% by weight to about 50% by weight of the tobacco product as defined in any of the preceding claims combined with a tobacco blend, the smokable rod being surrounded by a wrapping paper.

14. A smoking article as defined in claim 13, wherein the smokable rod includes the tobacco product in an amount sufficient to decrease a carbon monoxide to tar ratio by at least 5% such as by at least 10%, such as by at least 15% in comparison the same smoking article containing the same reconstituted tobacco material not including the polymer component or burn retardant.

15. A smoking article as defined in claim 14, wherein the carbon monoxide to tar ratio is decreased by from about 5% up to about 25%.

16. A tobacco product as defined in any of the preceding claims, wherein the coating comprises a film on the surface of the reconstituted tobacco material.

17. A method for forming a reconstituted tobacco material for use in a smoking article, the method comprising:

combining tobacco with a solvent to form a soluble component and an insoluble component;

removing at least a portion of the soluble component;

refining the tobacco;

recombining the refined tobacco with the soluble component; and prior to or after the soluble component is recombined with the refined tobacco, adding a burn retardant and a polymer component to the refined tobacco.

18. A method as defined in claim 17, wherein the burn retardant and polymer component are combined together and then added to the refined tobacco as a coating.

19. A method for forming a smoking article by combining the

reconstituted tobacco material produced in claim 17 or 18 with a tobacco blend to form a smokable rod and surrounding the smokable rod with a wrapping paper.

20. A reconstituted tobacco product comprising:

a tobacco material comprising tobacco stems and fines;

a tobacco soluble fraction combined with the tobacco material;

a burn retardant present in the tobacco material; and

a polymer component coated on at least a portion of the tobacco material.

21 . A reconstituted tobacco product as defined in claim 20, wherein a burn retardant is contained in the tobacco product and comprises a carbonate, a phosphate, or mixtures thereof.

22. A reconstituted tobacco product as defined in claim 21 , wherein the burn retardant comprises an alkali metal salt or an ammonium salt of a carbonate or a phosphate.

23. A reconstituted tobacco product as defined in claim 20, wherein the burn retardant is present in an amount from about 0.1 % to about 20% by weight, and the polymer component is present in an amount from about 0.1 % to about 10% by weight.

24. A reconstituted tobacco product as defined in claim 20, wherein the burn retardant is present in an amount from about 5% to about 20% by weight, and the polymer component is present in an amount from about 0.5% to about 5% by weight.

25. A smoking article as defined in any of claims 20 through 24, comprising a smokable rod containing from about 10% by weight to about 70% by weight, such as from about 15% by weight to about 50% by weight of the reconstituted tobacco product as defined in any of claims 20 through 24combined with a tobacco blend, the smokable rod being surrounded by a wrapping paper.