AU763222B2 - Smoking article and smoking material thereof - Google Patents

Description

-1-

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: British American Tobacco (Investments) Limited Actual Inventor: Kevin Gerard McAdam and Philip John Biggs and Richard Thomas Gilbert and Bhasker Natarajan Address for Service: BALDWIN SHELSTON WATERS 60 MARGARET STREET SYDNEY NSW 2000 CCN: 3710000352 Invention Title: 'SMOKING ARTICLE AND SMOKING MATERIAL THEREOF' Details of Original Application No. 76680/98 dated 29 May 1998 The following statement is a full description of this invention, including the best method of performing it known to me/us:- File: 26194AUP01 *00 1A Smoking Article and Smoking Material therefor The subject invention relates to smoking articles, cigarettes for example, and smoking material therefor.

The patents literature contains many proposals for smoking materials for use in place of conventional cut tobacco cigarette filler.

It is an object of the subject invention to provide new smoking materials which provide for mainstream smoke which although containing low levels of tobacco derived components, is fully acceptable to the consumer or to at least ameliorate at least one of the disadvantages in the prior art.

The subject invention provides a smoking article comprising a smokable rod and a filter, the smokable rod comprising smoking material and the filter comprising filtration material provided with an elutable aerosol generator which is a non-polyol aerosol generator being one or more of triethylene glycol diacetate, glycerol triacetate and glycerol diacetate, the aerosol generator being elutable from the filter upon smoking of 15 the smoking article to enhance the aerosol provided from the smoking material.

Unless the context clearly requires otherwise, throughout the description and the claims, the words 'comprise', 'comprising', and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to".

20 Triethylene glycol diacetate ('TEGDA'), glycerol triacetate ('triacetin') or glycerol diacetate ('diacetin'), for example, can be used as the non-polyol aerosol generator either individually or in combination. As is well known to those skilled in smoking article science and technology, TEGDA and triacetin are substances with an established use as plasticisers (bonding agents) for cellulose acetate cigarette-filter tow. It was thus surprising to find that these substances and similar substances, when used as aerosol -2generating substances in smoking materials according to the subject invention, provide aerosols in mainstream smoke which smokers register as very acceptable.

Non-polyol aerosol generator is usefully present in smoking materials of the subject invention at levels in a range of about 2% to about 30% by weight. More usually the range will be about 5% to about 20% by weight, and more usually 5-15%.

Total aerosol generator can include a polyol aerosol generator, such as for example one or more of glycerol, propylene glycol and triethylene glycol.

Smoking materials according to the subject invention can, as will be readily appreciated by those skilled in the art, be fabricated by slurrying the components, in fine particulate form, with water and casting the slurry to sheet form on a band or wire sheetforming machine or on a heated drum. An alternative is to feed a mixture of the components, together with water, to an extruder. The product of casting or extrusion is suitably cut and shredded to provide smoking material of particulate form.

If the components used to provide the smoking material do not include tobacco, then advantageously the smoking material, in particulate form, is blended with .particulate tobacco. In such case, the smoking material expediently accounts for at least about 30% by weight of the blend. Suitably, the smoking material will account for the 'i majority, by weight, of the blend, that is more than 50% by weight of the blend. The tobacco in the blend may be expanded tobacco.

:i 20 A class of substance suitable for the selection therefrom of binder in smoking materials according to the subject invention is the alginates. Sodium alginate has been found to be advantageous. Other suitable binder substances are celluloses or modified celluloses, hydroxypropyl cellulose or carboxymethyl cellulose, for example, starches or modified starches and natural gums.

-3- Suitable substances for use as inorganic filler are calcium carbonate, perlite, vermiculite, diatomaceous earth, colloidal silica, magnesium oxide, magnesium sulphate, magnesium carbonate or other low density inorganic filler materials known to those skilled in the art.

In smoking materials according to the subject invention inorganic filler is preferably present at a level of at least about 35%, preferably at least about 40% and more preferably at least about 45% by weight.

In smoking materials according to the subject invention tobacco may be present at less than 15%, preferably less than 10% and more preferably less than The binder of smoking materials according to the invention may be present at less than 15%, and more preferably less than 10% by weight.

Smoking materials according to the subject invention may comprise one or more mechanical stabiliser or strengthening materials, examples being cocoa, sugar and fibre, paper fibre for instance. Expansion medium, such as starch, pullulan or other i: 15 polysaccharides or foaming agents, for example, and high fat or high oil materials, such as cocoa butter or olive oil, corn oil, for example, may also be advantageously included.

Much by preference, in smoking articles in accordance withthe subject invention S..both the core and the outer part of the smokable rod extend over the full length of the rod. It is much by preference too for the core to be disposed coaxially of the rod.

i 20 The smoking article may be of a coaxial arrangement or non-coaxial arrangement.

•Oo.oi Advantageously the smoking material comprises an aerosol generator, a binder and an inorganic filler, and is more advantageously comprised of a non-polyol aerosol generator, up to 20% by weight tobacco, binder at not more than 20% by weight and not -4less than 30% by weight inorganic filler. Alternatively the smoking material may comprise one or more of the aerosol generating means or aerosol generating fuel sources of our co-pending application filed on 6 September 1995 under International Patent Application No. PCT/GB 95/02110. As a further alternative, the smoking material may comprise conventional cut tobacco leaf material.

The aerosol generator may be a polyhydric alcohol, an ester, a high boiling point hydrocarbon, glycerol, propylene glycol, triethylene glycol, methylene glycol, methyl citrate, triacetin or diacetin, either alone or in combination.

In a smoking article of an exterior circumference conventional for a cigarette, i.e.

c.25mm, the exterior circumference of the said core is suitably about 17mm.

EXAMPLE 1 A smoking article, a cigarette, exemplary of the subject invention comprised a core of approximately 17mm circumference, which core consisted of cut lamina filler conventional for ultra-slim cigarettes, such, for example, as the ultra-slim cigarette made by British American Tobacco (Germany) under the brand name CAPRICE, and a wrapper of conventional cigarette paper. The outer part of the cigarette disposed S"annularly about the core consisted of a blend of 50% by weight of expanded lamina tobacco and 50% by weight of a smoking material according to the subject invention enwrapped in an outer wrapper of low sidestream cigarette paper made by Glatz Inc.

20 under the experimental designation GNS40MV. The expanded tobacco had been °•om• expanded by the well known Dry Ice Expanded Tobacco (DIET) tobacco expansion process. The smoking material according to the subject invention, which had been band cast and then cut and shredded, had a percentage composition by weight as follows.

TEGDA 2.6 Glycerol Conventional Tobacco Blend (ground) 19.8 Sodium Alginate 9.9 Chalk 48.3 Cocoa 6.4 Demerera Sugar Paper Fibre The core and the outer part were lengthwise coterminous.

The cigarette according to the subject invention further comprised a conventional ventilated fibrous cellulose acetate filter..

EXAMPLE 2 A second exemplary smoking material in accordance with the subject invention is of a percentage composition by weight as follows.

TEGDA 6 15Glycerol 6 *15 Conventional Tobacco Blend (ground) Sodium Alginate Chalk 51 Cocoa 4 Demerera Sugar 3 20 This second smoking material in cut and shredded form could, for example, be blended with a conventional cut tobacco cigarette filler. The ratio in the blend of smoking material to filler might, for instance, be 7:3. The blend could be fed to a cigarette making machine to provide cigarette rod comprising the blend and a wrapper of conventional cigarette paper or a low sidestream paper, for example.

-6- EXAMPLE 3 A third exemplary smoking material in accordance with the subject invention is of a percentage composition by weight as follows.

TEGDA Glycerol 4 Sodium Alginate 8 Chalk 78 This third smoking material in cut and shredded form could, for example, be blended with conventional cut tobacco filler in a ratio of, for instance, 4:6 and used for the provision of cigarette rod.

EXAMPLE 4 The following three smoking material formulations were prepared for comparison.

The compositions are percentage by weight of each component.

*C*

C

C

C

-7- TABLE 1 Triacetin Glycerol Conventional Tobacco Blend (ground) Sodium Alginate Fibre Perlite 1 0 8.6 20.3 8.1 1 62 Sample Number 2 9.6 0 20.1 8 1 61.3 Smoke Deliveries Puff No.

TPM (mg/cig) Water (mg/cig) Nicotine (mg/cig) Glycerol (mg/cig) Triacetin NFDPM (mg/cig) NAFDPM (mg/cig) 3.4 7.5 2.7 0.19 1.11 n/m 4.59 3.48 5.3 5.3 0.8 0.1 n/m 2.03 4.36 2.33 o o* "222.

go* 7.6 2.1 0.2 n/m n/m 5.35 n/m NAFDM Nicotine, aerosol free dry particulate matter (aerosol being glycerol or triacetin).

NFDPM Nicotine free dry particulate matter.

n/m Not measured The cigarettes were smoked under standard machine smoking conditions of 3 puff of 2 seconds duration taken every minute to a butt length of EXAMPLE 0 In order to observe the influence of an aerosol generator held on a filter element against a smoking article having a standard fibrous cellulose acetate filter the mixed -8glycerol and triacetin sheet (Sample 3 of Example 4 above) was used in smoking articles with an aerosol generator in the filter at various levels. The cigarettes were of 84mm length, c.8mm diameter with a 27mm filter element and were smoked under standard machine smoking conditions to 35mm butt length. The aerosol generator on the filter was propylene glycol (PG).

TABLE 2 PG on filter (mg) Smoke Deliveries Puff Number TPM (mg/cig) Water (mg/cig) Nicotine (mg/cig) NFDPM (mg/cig) Smoke Composition Water Nicotine Sample Number 4 5 6 7 8 0 5 10 20 4 7.6 2.05 0.20 5.35 27.0 2.6 4 5.7 1.35 0.17 4.18 23.7 3.0 4 7.56 1.33 0.17 6.06 17.6 2.2 3.75 8.4 1.58 0.13 6.69 18.8 1.5 4 11.6 2.23 0.15 9.22 19.2 1.3 *r It can be seen that the presence of additional aerosol generator dilutes the smoke constituents and provides a useful means for reducing the smoke delivery levels of 10 various smoke components.

EXAMPLE 6 Other formulations of smoking material according to the invention were made according to Table 3. Additional materials included starch, oils and alkaline water. In Sample 58a a 0.1M solution of sodium carbonate was made up and added to the dry -9mixture instead of the usual water, until the required pH was reached. The compositions are percentage by weight of each component. 0 0 00 00 0 0000 0* 0 0 0* 000000 0 000000 0000 0* 00 0 0 0 4 4 4 0 *0* *0 0 00 00 0 *00 0 0 0 0 i **i 0 0 *0 00 TABLE 3 Sample No.

2a 3a 7a 8a Ila 1 2a 1 6a 1 7a 26a 34a 39a 41a 42a 51a 52a 58a Tobacco Sodium Alginate Sugar Cocoa Chalk Glycerol Tegda Triacetin Other Components 10 (Paper Fibre) 10 (Starch) 10 (Cocoa Butter) 10 (Corn oil) 51 (Perlite) 25 (Perlite) 15 (Cooked Starch) 15 (Olive Oil) pH=9.3

Claims (9)

11- THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:- 1. A smoking article comprising a smokable rod and a filter, the smokable rod comprising smoking material and the filter comprising filtration material provided with an elutable aerosol generator which is a non-polyol aerosol generator being one or more of triethylene glycol diacetate, glycerol triacetate and glycerol diacetate, the aerosol generator being elutable from the filter upon smoking of the smoking article to enhance the aerosol provided from the smoking material. 2. A smoking article according to Claim 1, wherein said elutrable aerosol generator further comprises a polyol aerosol generator. 3. A smoking article according to claim 1 or 2, wherein said rod comprises an axially arranged core disposed within an annulus. 4. A smoking article according to Claims 1, 2 or 3, wherein said smoking material comprises an aerosol generator, a binder and an inorganic filler. 15 5. A smoking article according to Claim 4, wherein said smoking material comprises a non-polyol aerosol generator, tobacco at up to 20% by weight, binder at not more than 20% by weight and not less than 30% by weight ~inorganic filler. 6. A smoking article according to Claim 4, wherein said smoking material 4 20 comprises a non-polyol aerosol generator, no tobacco, binder at less than 10% by weight and not less than 30% by weight inorganic filler. 7. A smoking article according to Claims 5 or 6, wherein said non-polyol aerosol generator is present in said smoking material in a range of about 2% to about by weight. -12- 8. A smoking material according to Claim 7, wherein said non-polyol aerosol generator is present in a range of about 5% to about 20% by weight. 9. A smoking material according to Claim 8, wherein said non-polyol aerosol generator is present in a range of about 5% to about 15% by weight. 10. A smoking material according to any one of Claims 5 to 9, wherein said inorganic filler is present in said smoking material at a level of at least 35% by weight. 11. A smoking material according to Claim 10, wherein said inorganic filler is present at a level of at least 40% by weight.

12. A smoking material according to Claim 11, wherein said inorganic filler is present at a level of at least 45% by weight.

13. A smoking material according to any one of Claims 4-12, wherein said tobacco in said smoking material is present at less than 15% by weight.

14. A smoking material according to Claim 4, wherein said tobacco is present at less than 10% by weight.

15. A smoking material according to Claim 14, wherein said tobacco is present at less than 5% by weight. °ooo•

16. A smoking material according to any one of Claims 4-12, wherein said binder in said smoking material is present at less than 15% by weight. 20 17. A smoking material according to Claim 16, wherein said binder is present at less than 10% by weight.

18. A smoking material according to any one of Claims 4-17, wherein said inorganic filler is one or more of calcium carbonate, perlite, vermiculite, diatomaceous earth, colloidal silica, magnesium oxide, magnesium sulphate, magnesium 13- carbonate or other low density inorganic filler materials, having a density similar to the materials cited in the group.

19. A smoking article according to any one of Claims 4-18, wherein said binder is one or more of an alginate, celluloses or modified celluloses, starches or modified starches, and natural gums. A smoking material according to any one of Claims 4-19, wherein said smoking material further comprises a mechanical stabiliser or strengthening material, an expansion medium or a high fat or high oil containing material.

21. A smoking material according to Claim 20, wherein said material further comprises one or more of cocoa, sugar, fibre, starch, pullulan, polysaccharide expansion agents, foaming agents, cocoa butter, olive oil and corn oil. DATED this 8th Day November 2001 BRITISH AMERICAN TOBACCO (INVESTMENTS) LIMITED Attorney: DENIS E. TUFFERY 15 Registered Patent Attorney of BALDWIN SHELSTON WATERS