ES2243125A1 - Filter for reducing the harmful substances present in smoke - Google Patents

Abstract

This invention relates to a filter to reduce the quantity of all or part of the harmful substances present in smoke, which comprises a sulfated polysaccharide or else a mixture of sulfated polysaccharides, in acid form or forming a salt, where the sulfated polysaccharide is selected from the group consisting of chondroitin sulfate, heparin, hyaluronic acid sulfate, keratan sulfate, inulin sulfate, xanthan sulfate, gellan sulfate, pullulan sulfate, curdlan sulfate, alginic acid sulfate, laminarin sulfate, pectin sulfate, dermatan sulfate, and heparan sulfate, where the sulfated polysaccharide may be totally or partially hydrolised. Preferably, the sulfated polysaccharide is chondroitin polysulfate sodium salt and the filter is a tobacco smoke filter.

Description

Filter to reduce harmful substances present in the smoke

Technical sector of the invention

The present invention relates to a filter for reduce the harmful substances present in the smoke. Likewise the present invention relates to a filter for the smoke of the tobacco, a procedure to prepare the filter and its utilization. It also refers to an article for smoking, more in Concrete to a cigarette.

Prior art

The smoke emitted by the facilities industrial and automobiles, as well as that coming from forest fires, contain substances that pollute the environment environment and that due to their toxicity exert a long-term pernicious effect on people's health.

Another type of smoke, no less worrying, is the which comes from the combustion of tobacco.

Primary smoke is the smoke that is introduced into the mouth when the smoker smokes, and the secondary smoke is the one that it follows from the lit end of the smoking article, by example the cigarette.

Tobacco smoke is a very complex mixture. He tobacco contains thousands of different components (in tobacco it have identified approximately 2,500). More than 4,000 are formed compounds when tobacco burns at varying temperatures with variable oxygen concentrations, among them is the nicotine, which is the agent that creates addiction, and tar (solid product consisting of a set of substances most of them carcinogenic).

It is estimated that tobacco is responsible for five million deaths a year worldwide.

For smokers, the health risks of Tobacco use include: lung disease (emphysema, chronic bronchitis, lung cancer), coronary heart disease (angina, heart attacks), atherosclerosis and vascular disease peripheral (aneurysms, hypertension, clots, strokes), oral / dental / gum diseases (including oral cancer), other cancers (kidney, bladder and pancreas) and in pregnancy, increased fetal death, premature delivery and low weight children by be born.

For non-smokers, exposed so indirect to smoke, health risks include: increase of lung cancer risk, compared to those who are not exposed to smoke, and in infants and children an increase in frequency of respiratory infections, so it is very important Prepare filters for enclosures where you can smoke.

Attempts to reduce the amount of compounds Toxic that reach the smoker has led to the preparation of tobacco smoke filters that are located between the tobacco that It burns and the smoker.

Conventional filters are prepared with cellulose acetate, with or without activated carbon. However, these conventional filters are only partially effective in the reduction of the amount of toxic compounds and carcinogens. In addition, those containing activated carbon are not well received by smokers because they reduce the aroma and taste of smoke.

Some patents describe procedures chemicals to reduce tar and nicotine from tobacco. These Chemical compounds are usually carboxylic acids, metals and transition metal oxides.

EP 673,667 describes a filter film that comprises a matrix of polymeric organic material (for example paper) with granules of calcium phosphate compounds dispersed in she. In the description they cite that calcium phosphate granules may contain active substances adsorbed on its surface, to modify its physicochemical properties and its properties immunological These active substances can be, for example, polysaccharides, and among them they cite chondroitin sulfate. In addition to not being described in any example, in any case use chondroitin sulfate alone without being adsorbed on the calcium phosphate granules, to reduce harmful substances Present in the smoke.

US 4,242,226 describes a filter comprising a product in the form of an activated carbon matrix containing scattered inside a metal. Said product is formed by chemical reaction between cations of a metal and anionic groups chemically bound to a substance that consists essentially of a polyhexose derivative, followed by pyrolysis and activation of said product. In the description they cite that polyhexose can be, for example, inulin and anionic acid groups sulfonic It is clear that the product that contains the filter is not inulin sulfate, this sulfated polyhexose can be used as raw material that is processed before preparing the product of filter.

Some patent documents describe filters for tobacco smoke containing alginic acid or alginates. Among these documents we will cite: JP 7039361, GB 654.994, FR 1,081,215 and JP 56091836.

However, so far it has not been found described no filter containing alginic acid sulfate.

A sulfated polysaccharide that has been described for use in the manufacture of filters to reduce the harmful substances present in the smoke, and more specifically filters for tobacco smoke, is cellulose sulfate. US Patent 3,661,160 refers to a filter for tobacco smoke comprising sodium ethyl sulfate sulfate.
slab.

However, so far it has not been found described no filter containing cellulose polysulfate.

In US Patent 5,947,127 they cite that the carrageenan (polysaccharide that already contains in its structure groups sulfate) can be included in the tobacco filter as an adhesive. They use this water-soluble polysaccharide to avoid the use of plasticizers

We have not found described any filter that contain carrageenan polysulfate.

For all that has been said it follows that there is a need for an improved filter to reduce the amount of harmful substances present in the smoke, and more especially in the tobacco smoke, keeping in the latter case a level Enough aroma and taste of smoke. Thus, providing new filters is a topic of great interest for both human beings and For the enviroment.

Explanation of the invention.

The present invention provides a new filter. to reduce the amount of all or part of the substances harmful in smoke, which comprises a polysaccharide sulfated or a mixture of sulfated polysaccharides, in the form acidic or forming a salt, in which the sulfated polysaccharide is select from the group consisting of sulfate Chondroitin, heparin, hyaluronic acid sulfate, queratane, inulin sulfate, xanthan sulfate, gelane, pululane sulfate, curdlano sulfate, acid sulfate alginic, laminarin sulfate, pectin sulfate, dermatan, heparan sulfate, cellulose polysulfate and carrageenan polysulfate, the polysaccharide may be totally or partially hydrolyzed sulphated.

In a preferred embodiment the sulfated polysaccharide is selected from the group consisting of: chondroitin sulfate; heparin; hyaluronic acid sulfate; keratane sulfate; inulin sulfate; xanthan sulfate; gelan sulfate; pululane sulfate; curdlano sulfate; alginic acid sulfate; laminarin sulfate; pecti- sulfate
na.

In an equally preferred embodiment the sulfated polysaccharide is a polysulfated polysaccharide selected from the group consisting of: polysulfate chondroitin; hyaluronic acid polysulfate; polysulfate queratano; inulin polysulfate; xanthan polysulfate; gellan polysulfate; pululane polysulfate; polysulfate curdlano; alginic acid polysulfate; laminarin polysulfate; pectin polysulfate, cellulose polysulfate, polysulfate carrageenan The most preferred polysulfated polysaccharide is the chondroitin sodium polysulfate, equally preferred is the inulin sodium polysulfate. Other polysulfated polysaccharide Preferred is cellulose polysulfate. Equally preferred is the carrageenan polysulfate.

Another aspect of the present invention is a procedure to prepare a filter for tobacco smoke that It comprises the following stages:

(a) preparation of an aqueous solution of the sulfated polysaccharide;

(b) application of the aqueous solution to a fibrous material in sufficient quantity for the polysaccharide sulfated retain harmful substances that result from combustion of tobacco;

(c) drying the filter so that the polysaccharide sulfate is in solid form.

In another equally preferred embodiment the filter is used for tobacco smoke, being preferably the sulfated polysaccharide in solid form dispersed in the material fibrous or with equal preference the polysaccharide being sulphated in solid form in a certain cylindrical section of the filter with the same diameter as the filter.

Another aspect of the present invention is the use of a filter for tobacco smoke, to reduce the amount of all or part of the harmful substances that result from the combustion of tobacco, especially when harmful substances they are the components of tar, as well as gases Toxic

Another aspect of the present invention is the use of a filter for tobacco smoke to reduce nicotine.

Another aspect of the present invention is a tobacco smoking article, preferably a cigarette.

The sulfated polysaccharides of the present invention are known, and can be obtained by sulfonation partial or total of the free hydroxyl groups present in the structure of commercial polysaccharides: sulfate Chondroitin, heparin, hyaluronic acid, keratane sulfate, cellulose, inulin, carrageenan, xanthan, gelane, pululane, curdlano, alginic acid, laminarin, pectin, dermatan sulfate or heparan sulfate.

The sulfonation of a hydroxyl group gives rise to corresponding sulfate group.

Chondroitin sulfate, heparin, keratane sulfate, dermatan sulfate, sulfate heparan and carrageenan are already polysaccharides partially sulfated.

When in the memory of the present invention Speaking of degree of sulfation refers to% of sulfate groups on anhydrous basis (with respect to the molecule).

When in the memory of the present invention talks about sulfated polysaccharide, refers to a polysaccharide sulphated with any degree of sulfation. By polysaccharide polysulphated means a sulfated polysaccharide with a high degree of sulfation, which includes the polysaccharide completely sulfated

Sulfated polysaccharides may be total or partially hydrolyzed by chemical or enzymatic methods. The The present invention includes both sulfated oligosaccharides (partial hydrolysis) as disaccharide units (hydrolysis total).

The sulfated polysaccharides can be obtained by partial or total sulfonation of the free hydroxyls of the commercial polysaccharides mentioned above, using methods described in the literature, such as by chlorosulfonic acid / pyridine (T. Astrup et al ., Acta Physiol. Scand. , 8 , 215-226 (1944)), either using piperidine- N- sulfonic acid (N. Kinzo et al ., Carbohyd. Res., 21 , 420-426 (1972)), or using the trioxide complex of sulfur-pyridine (C. Mähner et al ., Carbohyd. Res., 331 , 203-208 (2001)).

To obtain different degrees of sulfation, may modify the procedures mentioned above (vary reagent concentration, reaction temperature, times reaction etc ...). Also, if desired, they can be sulfonated. selectively different hydroxyl of the polysaccharide, by protection / deprotection of the polysaccharide hydroxyls.

When in the memory of the present invention talk about the sulfated polysaccharide forming a salt, it refers to an alkali metal salt, such as sodium or potassium, an alkaline earth metal salt, such as calcium or magnesium, or an organic salt such as salt with trimethylamine, with triethylamine, or with an amino acid, as per example lysine, arginine, proline, glycine or serine.

The salification of the sulfated polysaccharide is can carry out through simple chemical procedures well known.

The sulfated polysaccharide or the mixture of sulfated polysaccharides can be added in solution or in form solid to the fibrous material of a conventional filter or it can be use powder or granules as the main component of the filter.

If it is added in solution, the water sulfated polysaccharide and the resulting solution use it to spray or impregnate the fibrous material of a filter conventional, then drying it so that the polysaccharide sulfate is in solid form. In this way the polysaccharide sulfated will be dispersed in the fibrous material of the filter conventional.

If it is added in solid form, usually as powder, sulfated polysaccharide can be mixed with the material fibrous, compacting it later. In this case the polysaccharide sulfated will also be dispersed in the fibrous material of the filter conventional.

It can also be added in solid form so that the sulfated polysaccharide is in a certain cylindrical section of the filter with the same diameter as the filter. For this, for example, the filter of a conventional cigarette, formed of fibrous material, can be separated from the part of the cigarette containing the tobacco, without altering the paper that covers said filter, whereby an empty cylindrical container remains. The separated filter can be cut transversely into two parts, one of them can be placed back into the empty cylindrical container that was left. The sulfated polysaccharide, or the mixture of sulfated polysaccharides, can be applied in solid form on the part of the conventional filter reintroduced into the cylindrical paper container, forming a cylindrical section with the same diameter as that of the filter. The other part of the conventional filter that had been separated can then be replaced, making contact with the section of the sulfated polysaccharide, so that the cylindrical section of the sulfated polysaccharide remains in the inner part of the cigarette filter
commercial.

The sulfated polysaccharide can also be enter in the form of powder or granules in containers, by example nozzles, which can then be coupled, for example, to a cigarette, a pipe or a cigar. In this way the container can contain the sulfated polysaccharide alone or may additionally contain a fibrous support.

In the present invention when talking about tobacco smoking articles, refers, for example, to cigarettes, pipes or cigars.

An advantage that can be obtained with the invention is that the filters of the invention reduce notably an important part of the components of the tar.

Another advantage is that smokers, by smoking cigarettes containing the filters of the invention, not They detect that the aroma and taste of tobacco smoke is altered.

Detailed description of the preferred embodiments

The following examples are merely illustrative and do not represent a limitation of the scope of the present invention

Chemical examples Example 1 Chondroitin Sodium Polysulfate Preparation

A liner was added with 30 L of pyridine With stirring, 15 L of acid was slowly added chlorosulfonic, preventing the solution temperature from exceeding 75 ° C temperature. To the resulting mixture 10 were added Kg of chondroitin sulfate mixed with 20 L of pyridine. Be stirring continued and heated to 90 ° C, staying in these conditions for two hours. Then 250 L were added of methanol and stirring was maintained for a few more minutes, after which the stirring was stopped and allowed to decant.

The supernatant was separated and the precipitated with 100 L of a saline solution at temperature ambient. It was precipitated again by adding, with constant stirring, methanol He left stirring a few more minutes and stopped the agitation.

The supernatant was decanted and the precipitated with deionized water by stirring and at temperature ambient. Salt was added, the pH was readjusted to 5.3, heated to 90 ° C and hydrogen peroxide was added, maintaining these conditions and in stirring for 1 h. After this time it was filtered through of diatomaceous earth.

The resulting solution was ultrafiltered and diafiltered. three times through a molecular cut membrane comprised between 1,000 and 5,000 daltons.

The final solution was subjected to a treatment with hydrogen peroxide at a temperature of 45 ° C and for 40 minutes, after which sodium chloride was added again, it was stirred until complete dissolution and precipitated with methanol under stirring vigorous

It was allowed to decant, the supernatant was separated and anhydrified the solid. Drained and dried at 60 ° C under vacuum. He Dry product was ground and homogenized. Polysulfate was obtained Chondroitin sodium with a yield greater than 90%.

Degree of sulphation obtained (organic sulfates total): 41.5% expressed on an anhydrous basis

Free sulfates: <0.5%

IR (KBr) cm -1: 3467, 1634, 1235, 1055, 1024, 996, 820

Example 2 Preparation of inulin sodium polysulfate

With constant stirring and at a temperature < at 6 ° C, 88 mL (1.32 mol; 1.8 eq / OH) of chlorosulfonic acid on 580 mL (7.20 mol) of dry pyridine. The The resulting mixture was heated to 75 ° C and subsequently added 40 g (0.25 mol) of inulin (Fibruline Standar, marketed by Trades S.A.). Stirring and heating was continued at 100 ° C for 5 h. After this time the reaction mixture allowed to cool to about 50 ° C and 50 mL of deionized water to destroy excess chlorosulfonic acid. During this step the temperature of the medium rose slightly and Two phases appeared.

The reaction crude was allowed to stand until It reached room temperature. The upper phase (pyridine) is separated by suction, while the lower oil phase was poured on a 10% solution of sodium acetate in methanol. He precipitate that formed was allowed to settle. The supernatant is separated by decantation and discarded.

Treatment with the methanolic solution of Sodium acetate was repeated twice and in the last step the solid it was removed by vacuum filtration with a depth filter type k-100 (Pall Corporation. Seitz-K-100).

The obtained filter (brown solid) was dissolved in distilled water and the resulting solution was filtered under vacuum by a K-100 depth filter to remove traces of insoluble matter from the reaction.

The filtrate from the previous step was a dark amber solution that was treated with quaternary ammonium (Cuartamin). As a consequence, a very abundant solid formed which was isolated by vacuum filtration using a Hyflo land pre-layer (100 g). The filter is washed thoroughly with distilled water.

The polysulfate complex of inulin-Cuartamin was carefully separated from filtration soil and treated with an aqueous solution of NaCl 20%, at 80 ° C, for two hours.

After two hours of reaction, it stopped heating, and when the temperature of the medium reached 60 ° C it  added isopropanol. Stirring was maintained for 30 years. min. and then the mixture was poured into a separatory funnel to separate the aqueous phase from the organic one.

The organic phase (isopropanol + ammonium quaternary) was discarded. The aqueous phase was filtered under vacuum to Remove the remains of Hyflo land.

A mixture of methanol / acetone The brown precipitate that formed was left settling The supernatant was separated by decantation and discarded. The sediment was washed with methanol and subsequently dissolved in deionized water.

The pH of the resulting solution was adjusted between 10.5-11 with 10% NaOH. The solution was heated to 50 ° C and treated for 15 min with H 2 O 2. Finally I know the heating stopped and the pH of the medium was adjusted to 5.5 with a 2% acetic acid solution.

When the decolorized solution reached room temperature, a methanol / acetate solution was poured over it
to 10% sodium. Immediately a white or slightly yellow precipitate formed which was allowed to settle.

The supernatant was separated by decantation and the Sediment was abundantly anhydrified with methanol.

Inulin sulfate was filtered off at vacuum with porous plate No. 3 and dried in a vacuum oven at 30 ° C until the methanol concentration was equal to or less than 0.3%

The product was obtained as a fine, amorphous powder, White or slightly yellow.

Determination of the sulfation plow (organic sulfates) of inulin polysulfate obtained

Exactly 150 mg of product was weighed, dissolved in water and the resulting solution was brought to 250 mL with the same solvent. 5 mL of this solution was pipetted, transferred to a 50 mL beaker and 25 mL of water was added. It was titrated photometrically at 420 nm with a 0.1% solution of N- ethylpyridinium chloride (CPC) (0.00279 M).

Sulfate content was calculated by following equation:

% SO_ {4} = \ frac {V \ times 0.00279 \ times 96 \ times 100} {\ frac {5 \ times (100 - PPS) \ times P} {250 \ times 100}} = \ frac {13,392 \ times V \ times 100} {\ frac {100 - PPS} {100} \ times P}

Where:

V:

Volume consumed of the 0.1% CPC solution in mL

P:

Sample weight in mg.

PPS:

Weight loss due to product drying (105 ° C, 4 h) in%.

Degree of sulfation obtained: 58.0% expressed on anhydrous basis, which corresponds to an inulin molecule completely sulfated (sulfonation of all hydroxyls).

Residual salt-free pyridine: 127 ppm (the allowed limit is 200 ppm)

Free sulfates: 0.08%

IR (KBr) cm -1: 2900 (C-O-H), 1247 (S = 0), 800 (C-S-O)

Examples of filter efficiency Example 1 Comparison of the efficiency between a conventional filter that contains poultry and a conventional filter containing polysulfate chondroitin sodium

This procedure can be applied to the evaluation of a conventional filter containing any sulfated polysaccharide of the invention.

The filter of a commercial cigarette (brands Ducats or Fortuna) separated from the part of the cigarette that it contained the tobacco, without altering the paper that covered said filter, So there was an empty cylindrical container. The filter was cut transversely separated into two parts, one of them was placed again inside the empty cylindrical container that was left. He solid state chondroitin polysulfate was applied on the part of the conventional filter that had been reintroduced in the cylindrical paper container, forming a section cylindrical with the same diameter as the filter. Then the other part of the conventional filter was replaced had separated, making contact with the polysulfate section chondroitin sodium, so that the cylindrical section of Chondroitin Sodium Polysulfate remained inside the Commercial cigarette filter.

Following the same procedure, a filter that instead of chondroitin sodium polysulfate contained avicel (trade name of a microcrystalline cellulose).

This way Ducats cigarettes were prepared and Fortune with modified filters, in which in a given cylindrical section of the filter with the same diameter as that of the filter was chondroitin sodium polysulfate or poultry, in variable quantities (see Table 1).

The cigarettes were inserted in a machine Heinrich-Borwaldt Technik, model RM 200, machine specially designed for the analysis of smoke components of tobacco

The results are presented in Table 1.

After a certain number of suctions, proceeded to determine the amount of matter (TPM) retained in the fiberglass filter installed in the machine and through which it passes all the smoke sucked, that is, the one that comes from combustion of tobacco and that has passed through the cigarette filter. Be determined the amount of nicotine and water contained in the filter fiberglass, and with these data we proceeded to calculate the amount of tar (TAR). The results were expressed in mg / cigarette, and the data correspond to the average of four cigarettes

Table 1 shows the highest efficiency. of the filter containing chondroitin sodium polysulfate in comparison with the one containing poultry, both in regard to the reduction of the amount of nicotine as above all to the reduction of the amount of tar.

You can also see the greater effectiveness of filter when we increase the amount of sodium polysulfate from Chondroitin

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TABLE 1

one

Example 2 Determination of hydrogen cyanide, phenolic compounds and compounds containing carbonyl groups from the smoke of the tobacco, comparing a filter that contains poultry and one that contains chondroitin sodium polysulfate with a standard filter

This procedure can be applied to the evaluation of a conventional filter containing any sulfated polysaccharide of the invention.

The smoke analysis method of cigarettes from Arista Laboratories (www.aristalabs.co.uk).

The cigarettes in whose filter was incorporated Avicel or chondroitin polysulfate sodium were branded Marlboro commercial, and the filter preparation procedure of cigarettes is the same as detailed in Example 1 of Filter efficiency

The corresponding filter was taken as standard to Kentucky cigarette, reference 2R4F.

The results of the determination of phenols are they gather in Table 2, those of the determination of compounds that contain carbonyl groups in Tables 3 and 4, and the results of the determination of hydrogen cyanide in Table 5.

The data obtained correspond to the average of Three cigarettes

In all the tables a greater efficiency is observed of the cigarette whose filter contains sodium polysulfate of Chondroitin, significantly reducing the amount of all compounds studied that appear in the Tables.

Smoke sucked from a cigarette that contains in the chondroitin sodium polysulfate filter, it has a lower amount of highly toxic and carcinogenic compounds that form part of the tar (see Tables 2, 3, 4 and 5).

TABLE 2

2

TABLE 3

3

TABLE 4

4

TABLE 5

5

Claims (17)

1. A filter to reduce the amount of all or from the harmful substances present in the smoke, which it comprises a sulfated polysaccharide or a mixture of sulfated polysaccharides, in acid form or forming a salt, in the that the sulfated polysaccharide is selected from the group that It consists of chondroitin sulfate, heparin, acid sulfate hyaluronic acid, queratane sulfate, inulin sulfate, xanthan, gellan sulfate, pululane sulfate, curdlano, alginic acid sulfate, laminarin sulfate, sulfate of pectin, dermatan sulfate, heparan sulfate, polysulfate of cellulose and carrageenan polysulfate, the fully or partially hydrolyzed sulfated polysaccharide. 2. The filter according to claim 1, wherein the sulfated polysaccharide is selected from the group formed by: chondroitin sulfate; heparin; hyaluronic acid sulfate; keratane sulfate; inulin sulfate; xanthan sulfate; gelano sulfate; pululane sulfate; curdlano sulfate; alginic acid sulfate; laminarin sulfate; pectin sulfate 3. The filter according to claim 1, wherein the sulfated polysaccharide is a polysulfated polysaccharide selected from the group consisting of: chondroitin polysulfate; hyaluronic acid polysulfate; keratane polysulfate; inulin polysulfate; xanthan polysulfate; gellan polysulfate; pululane polysulfate; curdlano polysulfate; alginic acid polysulfate; laminarin polysulfate; pectin polysulfate; cellulose polysulfate; carrageenan polysulfate. 4. The filter according to claim 3, wherein the polysulfated polysaccharide is sodium polysulfate of Chondroitin 5. The filter according to claim 3, wherein The polysulfated polysaccharide is inulin sodium polysulfate. 6. The filter according to claim 3, wherein The polysulfated polysaccharide is cellulose polysulfate. 7. The filter according to claim 3, wherein The polysulfated polysaccharide is carrageenan polysulfate. 8. A procedure to prepare a filter for tobacco smoke according to claims 1 to 7 which It comprises the following stages: (a) preparation of an aqueous solution of the sulfated polysaccharide of claim 1; (b) application of the aqueous solution to a fibrous material in sufficient quantity for the polysaccharide sulfated retain harmful substances that result from combustion of tobacco; (c) drying the filter so that the polysaccharide sulfate is in solid form. 9. Use of a filter in accordance with the claims 1 to 7, for tobacco smoke. 10. Use according to claim 9, wherein the sulfated polysaccharide in solid form is dispersed in the material fibrous. 11. Use according to claim 9, wherein the sulfated polysaccharide in solid form is in a certain cylindrical section of the filter with the same diameter as the one of the filter. 12. Use of a tobacco smoke filter from according to claims 1 to 7 and 9, to reduce the amount of all or part of the harmful substances that result of the combustion of tobacco. 13. Use according to claim 12, wherein harmful substances are the components of tar. 14. Use according to claim 12, wherein harmful substances are toxic gases. 15. Use of a tobacco smoke filter from according to claims 1 to 7 and 9, to reduce the nicotine. 16. Article for smoking tobacco incorporating a filter according to claims 1 to 7. 17. Article for smoking tobacco according to claim 16, which is a cigarette.