WO2012104621A1

WO2012104621A1 - Smoking article

Info

Publication number: WO2012104621A1
Application number: PCT/GB2012/050200
Authority: WO
Inventors: Matthew Knight
Original assignee: British American Tobacco (Investments) Limited
Priority date: 2011-02-01
Filing date: 2012-01-31
Publication date: 2012-08-09
Also published as: GB201101714D0; AR085103A1

Abstract

The invention relates to a smoking article which demonstrates a reduced transfer of odour to a user's fingers. The filter of the smoking article comprises particulate sepiolite material and the rod of smokeable material comprises low sidestream wrapping paper.

Description

Smoking Article Field of the Invention

The invention relates to reduced odour smoking articles.

Background

Smoking articles generally give out a distinctive odour as they are smoked. This odour is transmitted via the sidestream smoke, and as a result, the fingers of the user can be particularly affected by the odour, which can be difficult to remove.

Previously, research activities have not typically been specifically aimed at reducing the transfer of odour to the user's fingers. Historically, approaches to reducing the odour emitted from smoking articles have instead focused on altering the quantity or properties of the smoke produced.

For example, a number of smokeless cigarettes have been developed which deliver nicotine without burning a smoking material. Smokers frequently find such smoking articles unsatisfactory, however, as they do not have the taste and feel of a conventional smoking article.

Alternatively, smoking articles have been described which are designed to mask or alter the odour emitted by the smoking article. For example, European Patent No. 0294972 describes a flavourant material, which pyrolyses on combustion to produce an aromatic agent which masks the odour of sidestream smoke. More recently, U.S. Patent No. 5,494,055 described an aroma mixture for reducing undesired sidestream smoke effects. The aroma mixture comprises at least vanillin, an aldehyde, and a heterocyclic compound in an ethanol solution and can be applied in encapsulated or unencapsulated form. However, it may be preferable to remove or reduce the odour, rather than simply mask it, and the present invention seeks to provide a smoking article that overcomes or substantially alleviates the problems described above. Statements of the Invention

According to a first aspect of the present invention, a smoking article is provided which is arranged to reduce transfer of odour to a user's fingers and comprises a filter and a rod of smokeable material. The filter comprises particulate sepiolite material and the rod of smokeable material comprises low sidestream wrapping paper.

The particulate sepiolite may be flavoured where permitted by regulation, for example, it may be mentholated. The smoking material may comprise expanded tobacco, such as dry ice expanded tobacco (DIET) in an amount of at least 70% of the total tobacco blend.

The filter of the smoking article may be ventilated. The particulate sepiolite material may be dispersed within the filter material. The particulate sepiolite material may additionally or alternatively be adhered to one or more portions of the plugwrap.

According to a second aspect of the invention, the use of a smoking article as described in the first aspect is provided to reduce odour transfer to the user's fingers.

According to a third aspect of the invention, a method of reducing the transfer of odour from a smoking article to the user's fingers is provided. The method comprises providing a smoking article as described in the first aspect.

Description of Dr wing

For a fuller understanding of the invention, reference is made to the accompanying drawing which illustrates an individual filter cigarette according to an embodiment of the invention (not to scale). Detailed Description

The accompanying figure shows a smoking article 1 comprising a filter 2. The filter 2 comprises a substantially cylindrical plug of filter material 3 wrapped in a plugwrap 4 around its circumferential surface. Particulate sepiolite is dispersed in the filter material 3 and is adhered to a portion 5 of the inner face of the plugwrap 4.

The smoking article further comprises a cylindrical rod of smokeable material 6, in this case, a blend of tobacco comprising 70% dry-ice expanded tobacco (DIET). The tobacco rod 6 is aligned with the filter 2, such that the end of the tobacco rod abuts the end of the filter. The tobacco rod is wrapped in a low sidestream paper wrapper 7, and is joined to the filter 2 by tipping paper 8 in a conventional manner.

The filter 2 is ventilated by means of perforations 9 in the tipping paper 8, and the use of a porous plugwrap 4.

Low Sidestream Wrapper

Inherently porous cigarette wrapper paper consists of an interlocking network of fibres, which are usually cellulose fibres, generally interspersed with particles of a filler such as calcium carbonate. Openings in the fibre/ filler matrix are of the order of 1 μπι wide, which dimension is small compared with the thickness of the paper (usually 20 to 50 μηι) and the flow of air through such openings is governed by viscous forces. In the embodiment shown in the accompanying figure, the tobacco wrapping paper 7 comprises sidestream-smoke reducing wrapping paper. This wrapping paper comprises a sidestream reducing filler substance, in an amount of up to 20% by weight. At least a proportion of this filler is capable of effecting visible sidestream reduction. Suitably, the visible sidestream reducing filler content is present in the range of about 4 to 20%, by weight, and is preferably present at between 4% and 10%. Preferably, the filler which effects a reduction in visible sidestream may be magnesium oxide, magnesium hydroxide, aluminium hydroxide, lithium hydroxide, high surface area chalk or a mixture thereof. The filler is preferably magnesium oxide of a reactive grade.

In addition to the visible sidestream reducing filler, the filler may comprise conventional chalk. If conventional chalk is present, it may be present in a range of between 5% and 20% by weight of the paper, and is preferably present at between 10% and 15% by weight of the paper.

The average size of the chalk particles may be between 0.5 μπι and 4 μπι, and is preferably between 0.7 μπι and 2 μπι.

The air permeability of a paper expressed in CORESTA Units (CU) is the amount of air (in cm³) which passes through one square centimetre of the paper in one minute at a constant pressure difference of 1.0 KPa. Conventional cellulose pulp paper wrappers have an inherent permeability (i.e. that due to viscous flow) in the range of 2 to 300 CU and generally less than 100 CU. The permeability of the paper used in the present invention is advantageously about 10 CU or less. The permeability is preferably about 7 CU or less, and is more preferably about 5 CU or less.

The weight of paper is suitably at least about 20 g/ m², preferably at least about 25 g/ m², and most preferably within a range of about 30 g/ m² to 40 g/ m².

In some embodiments, the wrapper further comprises a burn additive in a range of between 2% and 10%, by weight. Suitable burn additives will be known to the skilled person. Additives which may be used include sodium acetate, tri-potassium citrate, potassium di-hydrogen orthophosphate and potassium tartrate. The salts of the burn additives may be alkaline or acidic in aqueous solution. The burn additives may be either burn rate promoters or burn rate retardants. Sepiolite

The filter of the smoking article comprises particulate sepiolite material.

Sepiolite, formerly known as Meerschaum (sea froth), is a non-swelling, lightweight, porous clay with a large specific surface area (of about 300 m²/g), and a high capacity to adsorb vapours and odours. Chemically, sepiolite is a hydrated magnesium silicate with the ideal formula Si₁₂Mg₈O₃₀(OH)₄(OH₂) 4.8H₂O. Sepiolite particles have a needle-like morphology with an average length of 1 to 2 μπι, and a width of 0.01 μηι. These particles are arranged forming loosely packed and porous aggregates which explains the high surface area, porosity, and light weight of sepiolite and accounts for the remarkable adsorptive and absorptive properties of this clay.

In some embodiments, a flavourant is added to the sepiolite.

As used herein, the terms "flavour" and "flavourant" refer to materials which, where local regulations permit, may be used to create a desired taste or aroma in a product. Suitable flavourants may include extracts such as licorice, hydrangea, Japanese white bark magnolia leaf, chamomile, fenugreek, clove, menthol, Japanese mint, aniseed, cinnamon, herb, wintergreen, cherry, berry, peach, apple, Drambuie, bourbon, scotch, whiskey, spearmint, peppermint, lavender, cardamon, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, honey essence, rose oil, vanilla, lemon oil, orange oil, cassia, caraway, cognac, jasmine, ylang-ylang, sage, fennel, piment, ginger, anise, coriander, coffee, or a mint oil from any species of the genus Mentha. They may be imitation, synthetic or natural ingredients or blends thereof.

A preferred flavourant is menthol such as Indian menthol, which may be used in an amount of between about 0.2g and about 0.6g of menthol per gram of sepiolite, preferably about 0.4g of menthol per gram of sepiolite.

Applying flavourant to the sepiolite may have two advantages. Firstly, this allows flavourant to become entrained in the mainstream smoke from the sepiolite and as the user draws on the smoking article. Secondly, odour that is not adsorbed by the sepiolite may be masked by the flavourant.

The sepiolite particles used are preferably between 0.2 mm and 2 mm in diameter, and most preferably are between 0.5 mm and 1.3 mm.

The sepiolite may be incorporated into the filter in one or both of two ways. Firstly, the sepiolite may be adhered to the plugwrap in one or more patches. Secondly, the sepiolite may be interspersed in the filter material.

1. Sepiolite Adhered to the Plugwrap

The sepiolite may be disposed in discrete portions of the inner or outer surface of the plugwrap. In some embodiments, including the preferred embodiment shown in the accompanying figure, the sepiolite is disposed in a single patch on the inner face of the plugwrap.

In other embodiments, the sepiolite may be disposed in two portions which are diametrically opposed or otherwise circumferentially spaced from one another. In some embodiments, the sepiolite may be disposed in 3, 4, 5, 6, 7, 8, or more, separate regions each spaced circumferentially from one another.

In some embodiments, the plugwrap has an overlapping longitudinal edge which is free of sepiolite and which is suitable for the application of adhesive, thus providing a seam holding the wrapper around the filter material.

The sepiolite adhered to the plugwrap may be in contact with the filter material. In general, preferably substantially all of the sepiolite adhered to the wrapper is in contact with the filter material.

The plugwrap of the filter element is preferably a paper wrapper, for example, the plugwrap may simply be conventional plugwrap. However, to avoid bulging of the sections where the sepiolite is applied, it may be advantageous to use a plugwrap having a greater base weight compared with conventional plugwrap. Conventional plugwrap has a base weight of approximately 23 to 27 g/ m². In the present application, it is therefore preferable to use a plugwrap which has one of the following base weights: at least 26 g/m², at least 27 g/m², at least 28 g/m², at least 30 g/m², at least 33 g/m², at least 35 g/m², at least 37 g/m², or at least 40 g/m². The preferred base weight of the plugwrap is 27 g/m² for cork tipping and 35 g/m² for white tipping. The plugwrap may be porous or non-porous, and may be ventilated or unventilated. The plugwrap used is preferably porous and is used in combination with a ventilated tipping paper.

The plugwrap may be pre-coated with the sepiolite. Additionally or alternatively, sepiolite may be added during the filter manufacturing process.

The sepiolite may be directly adhered to the plugwrap, for example, by hot melt adhesive (for example, using various polyester adhesives), polyethylene glycol, or emulsion-type adhesive such as PVA.

Alternatively, the sepiolite may be indirectly adhered to the plugwrap. For example, the particulate material may be adhered to an intermediate layer (which may be made of paper or other suitable support matrix such as a textile material) by means of a suitable adhesive. The intermediate layer is adhered to the plugwrap by means of a suitable adhesive. Preferably, the adhesive is applied to the plugwrap, and then sepiolite is applied to the adhesive.

The core may be pre-formed before application of the coated plugwrap.

Alternatively, the formation of the core and application of the coated plugwrap may occur substantially simultaneously. 2. Sepiolite Interspersed in the Filter Material

In addition, or as an alternative, to being incorporated in the filter as a patch, sepiolite may simply be interspersed in the filter material in the form known as a Dalmatian filter. The particulate material may be interspersed throughout the filter material, or may be interspersed in some parts (but not all) of the filter material, and these parts may be evenly or unevenly distributed. For example, the sepiolite particles may be concentrated towards the tobacco rod end of the filter.

In the embodiment shown in the accompanying figure, the filter material 3

comprises cellulose acetate. In some embodiments, the filter material comprises fibrous cellulose acetate, polypropylene material, polyethylene material.

Alternatively or additionally, the filter may comprise a paper filter.

The skilled person will be aware of various suitable methods for incorporating sepiolite into the filter material. For example, the sepiolite particles may be sprinkled onto sticky cellulose acetate tow, which is then gathered in conventional manner and cut into the appropriate unit lengths. Alternatively, the filter material may be injected with sepiolite into the centre of the filter. Composite Filters

In the embodiment shown in the accompanying figure, the filter 2 comprises a single filter element comprising a plug of filter material 3 wrapped in plugwrap 4. Consequently, in this embodiment, the sepiolite in the filter material extends over the full longitudinal length of the filter.

In alternative embodiments, however, the filter may be a composite filter comprising a number of individual filter elements, some of which may not comprise sepiolite. Suitably the filter elements of the composite filter are arranged

longitudinally of one another with the end of each filter element abutting the next. Suitably the composite filter may have 2, 3, 4 or more, elements.

In some embodiments in which the filter is a composite filter, all of the different filter elements comprise sepiolite. In alternative embodiments, one or more of the elements may not contain sepiolite and may be a conventional filter element, for example, comprising cellulose acetate. The one or more filter elements comprising sepiolite may be located at any position within the filter. Suitably however, in composite filters in which one or more of the filter segments do not comprise sepiolite, the sepiolite containing segments are preferably located towards the tobacco-rod end of the filter. In addition, in the case of ventilated filters, it is preferred for the sepiolite containing filter segments to be located in a position corresponding to the ventilation means of the ventilated filter. In a triple filter, for instance, the filter element comprising sepiolite may be located at the smoking material end of the filter. Alternatively, the filter element comprising sepiolite may be the central section, when this section corresponds to the position of the ventilating means. Additional flavourant may be added directly to the filter material, or otherwise incorporated in the filter independently of the sepiolite, to provide the desired level of flavour and/ or aroma to the smoke.

Ventilated Filters

The filter may comprise ventilation means. For example, the ventilation means may comprise one or more holes in the plugwrap and/ or tipping paper. Alternatively, porous plugwrap and/ or tipping paper may be used.

In some embodiments, a porous plugwrap is used in combination with a pre- perforated tipping paper.

In other embodiments, non-porous plugwrap is used, and the tipping paper and plugwrap are subsequently perforated, for example by means of an on machine laser method (OML).

In the preferred embodiment shown in the accompanying figure, a porous plugwrap 4 is used in combination with a pre-perforated 9 tipping paper 8. The position of sepiolite in the filter may correspond to the position of the ventilation holes. For example the ventilation holes may correspond to the location of the sepiolite patches adhered to the plugwrap. Additionally or alternatively, the position of the ventilation holes may correspond to regions of filter material comprising particulate sepiolite. This is thought to allow sepiolite to adsorb odour that would otherwise diffuse out of the filter through the ventilation holes. In addition, odour may diffuse or become drawn into the filter via the ventilation holes and thereby be adsorbed by the sepiolite. The ventilation holes in the plugwrap and/ or tipping paper are preferably positioned in a circumferential band around the filter, as shown in the embodiment of the accompanying figure. The ventilation holes can be arranged in a single row around the filter, or in a zone comprising two or more closely spaced rows. The number of holes in the row or zone, and the spacing between the holes, can be selected to give the desired level of ventilation. Further, deep holes of varying depth may be combined in a single row or zone, possibly further combined with conventional shallow ventilation holes. The ventilation holes may be situated 5 to 20 mm from the mouth end of the filter. Preferably the ventilation holes are situated 10 to 15 mm, most preferably 13 mm from the mouth end of the filter.

Smoking Material

In the embodiment shown in the accompanying figure, the smokeable material 6 comprises tobacco and is joined to the filter 2 by tipping paper 8 in a conventional manner. Generally, the filter is attached to the rod of smokeable material by conventional tipping overwrap to form a smoking article.

According to some embodiments, the smoking material comprises a proportion of expanded tobacco such as dry ice expanded tobacco (DIET). The expanded tobacco suitably has a bulk density in a range of 100 to 175 mg/ cm³. The proportion of the smoking material accounted for by expanded tobacco may be at least about 40% by weight and may suitably be at least about 50% by weight, and is preferably at least about 60%, 65%, 70%, 75%, 80%, or 85% by weight. Most preferably, the proportion of the smoking material accounted for by expanded tobacco is about 70% of the overall blend.

The smoking material which is not expanded tobacco preferably comprises leaf tobacco, suitably in conventional cut filler form. The leaf tobacco may be lamina and/ or stem tobacco. The smoking material may comprise a reconstituted tobacco or a tobacco substitute.

The length of the rod of smokeable material is preferably not less than 45 mm, is advantageously at least 55 mm, and is preferably not less than 60 mm.

The smoking material rods are preferably of uniform circular cross-sectional shape and dimensions throughout the lengths thereof, generally having a circumference of about 10 to 30 mm. Preferably, the rod circumference is not less than 12.5 mm.

When smoked under CORESTA standard machine smoking conditions, the smoking article should provide not less than 5 puffs, preferably not less than 6 puffs, and most preferably not less than 7 puffs. Smoking Article

Smoking articles comprising two or more of the following features:

(a) sepiolite in a patch or Dalmatian filter;

(b) flavouring applied to the sepiolite;

(c) low sidestream wrapper; and/ or

(d) a tobacco blend comprising greater than 70% of dry ice expanded tobacco; have been found to have a greater than expected capacity to reduce the transfer of odour to the fingers of the smoker.

Examples

Smoking Articles

Test cigarettes comprising sepiolite were prepared in a conventional manner. The filter tip of each cigarette contained 90.4 mg of sepiolite in the form of a patch adhered to the plugwrap of 19 mm in length and 16 mm in width. The sepiolite used in the test cigarettes was mentholated in an amount of 4.02 g of menthol per 10.5 g of sepiolite.

The filter of each test cigarette was ventilated using a conventional on-machine laser method, with the ventilation holes positioned to perforate the sepiolite patch.

The test cigarettes contained a 70% DIET blend of tobacco, which was wrapped using low sidestream wrapping paper. In all other aspects, the cigarettes, were produced in a conventional manner. The tobacco rod was 56 mm in length, and the filter was 27 mm in length and comprised a plug of cellulose acetate.

Control cigarettes were also produced, which were identical to the test cigarettes in all aspects, with the exception of having a standard (not low sidestream) cigarette paper, and containing no sepiolite. In a further difference, the test cigarettes were 1 mg products, whereas the control cigarettes were 10 mg products.

Experimental Design

In each test, four smokers, two male and two female, each smoked one test cigarette and one control cigarette. The control and test cigarettes were held in the opposite hands, and the same hand was used for each cigarette throughout the study.

After smoking, the subject's fingers were inserted into specially designed containers. The contents of the containers were then sampled by a panel of odour testers, to determine which of the two containers (corresponding to the control or test cigarette) had the stronger odour.

Test 1

In the first test, a panel of 4 judges sampled each of the containers.

All four panellists determined that the control containers had a stronger odour than the containers corresponding to the test cigarettes. Test 2

The containers generated in the second test were sampled by a panel of 27 judges. A 67% difference between the control and test samples was observed. The test samples were found to have a lower odour, and this finding was statistically significant (with a 5% level of significance).

Test 3

In the first test, a panel of 13 judges sampled each of the containers.

A 73% difference between the control and test samples was observed. The test samples were found to have a lower odour, and this finding was statistically significant (with a 5% level of significance).

In conclusion, the results of the sensory panel test clearly indicate that the test cigarettes show a reduced perceivable odour transfer to the fingers of the smoker.

Claims

1. A smoking article arranged to reduce transfer of odour to a user's fingers, comprising a filter and a rod of smokeable material, wherein the filter comprises particulate sepiolite material and the rod of smokeable material comprises low sidestream wrapping paper.

2. A smoking article according to claim 1, wherein the particulate sepiolite material is flavoured.

3. A smoking article according to any of the preceding claims, wherein the filter is ventilated.

4. A smoking article according to any of the preceding claims, wherein particulate sepiolite material is present in the filter in one or more patches on the surface of the filter wrapper.

5. A smoking article according to any of the preceding claims, wherein particulate sepiolite material is dispersed within the filter material.

6. A smoking article according to any of the preceding claims, wherein the smoking material comprises at least 70% DIET tobacco.

7. A smoking article according to any of the preceding claims, wherein the low sidestream wrapping paper comprises 20% by weight, or less, of a filler which is capable of effecting visible sidestream reduction, the weight of the paper being about thirty grams per square metre or more.

8. The use of a smoking article according to any of claims 1 to 7 to reduce odour transfer to a user's fingers.

9. A method of reducing the transfer of odour from a smoking article to a user's fingers, the method comprising providing a smoking article according to any of claims 1 to 7.