CN117814529A

CN117814529A - Tobacco smoke filter

Info

Publication number: CN117814529A
Application number: CN202410098072.8A
Authority: CN
Inventors: 詹姆斯·里德; 艾哈迈德·法希胡尔·利桑; 伊丽莎白·格林格; 肯尼斯·塔利
Original assignee: Essentra Filter Products Development Co Pte Ltd
Current assignee: Essentra Filter Products Development Co Pte Ltd
Priority date: 2013-09-11
Filing date: 2014-09-10
Publication date: 2024-04-05
Also published as: PL3043662T3; CN105813483A; JP2021119778A; RU2016111367A; JP2016533764A; US20160219930A1; KR20160054505A; GB201316210D0; WO2015036454A1; JP2019146577A; EP3043662A1; LT3043662T; EP3043662B1; RU2696025C2; RU2016111367A3; KR102358588B1

Abstract

The present application relates to a tobacco smoke filter, and a tobacco smoke filter element, comprising: a longitudinally extending core of tobacco smoke filter material having a circumference of 14mm to 17 mm; and an additive-releasing container completely enclosed within the core; wherein the filter material is a filiform material having a denier per filament of 5.3 or greater and a total denier of 18000 or less.

Description

Tobacco smoke filter

The present application is a divisional application of chinese patent application titled "tobacco smoke filter", application No. 201480050217.1, and patent application 201480050217.1 is a national application entering the national stage of china according to international application filed under the patent cooperation strip about 10/9/2014 (PCT/EP 2014/069328).

Technical Field

The present invention relates to tobacco smoke filters and filter elements, for example for smoking articles such as cigarettes.

Background

The manufacture and use of cigarette filters containing breakable capsules is well known. These capsules release the liquid or substance contained in these capsules (typically flavoring agents) when ruptured by the smoker before, during or after smoking, which can in turn be transferred to the cigarette smoke when the cigarette is smoked or to the surrounding environment after the cigarette has been extinguished.

It is also known to provide cigarette filters of a variety of different perimeters, typically from about 25mm to about 14mm. As the filter perimeter decreases within this range (e.g., from about 24.5mm, to about 23mm, to about 16mm to 17mm, to about 14mm to 15mm, respectively), it is referred to as "standard", "fine", "ultra-fine" and "fine" products. However, to date, filters containing capsules in ultra-fine (about 16mm to 17mm perimeter) and micro (about 14mm to 15mm perimeter) specifications have not been commercially developed. One of the problems is that the capsules tend to occupy a relatively high proportion of the cross-sectional area of the ultra-fine or microfilter product, resulting in an unacceptably high pressure drop (as the smoke is directed through the narrower channels around the capsule).

Disclosure of Invention

According to the present invention, in a first aspect there is provided a tobacco smoke filter or filter element comprising a longitudinally extending (e.g. generally cylindrical) core of tobacco smoke filtering material having a circumference (e.g. perimeter) of 14mm to 17mm (e.g. 16mm to 17 mm); and an additive-releasing container (e.g., a capsule) completely enclosed within the core; wherein the filter material is a filiform material (e.g., filiform filter tow) having a denier per filament of 5.3 or greater and a total denier of 18000 or less.

Preferably, the longitudinally extending core of tobacco smoke filter material is a generally cylindrical core of tobacco smoke filter material.

Preferably, the longitudinally extending core of tobacco smoke filter material has a perimeter of 16mm to 17mm (that is, the filter or filter element is an ultra-fine filter or ultra-fine filter element).

The filter or filter element may also include a wrapper (e.g., paper, tipping paper) engaged about a longitudinally extending (e.g., generally cylindrical) core. The wrapper may be a paper wrapper, such as a breathable paper wrapper.

The additive-releasing container (e.g., capsule) is entirely enclosed within a longitudinally extending (e.g., generally cylindrical) core of tobacco smoke filter material. This means that the additive release container (e.g. capsule) is not visible at the mouth end or mouth end of the filter/filter element, or at the mouth end of a cigarette comprising the filter of this aspect of the invention (for the smoker) when in use. Preferably, at least one end of the longitudinally extending (e.g., generally cylindrical) core of tobacco smoke filtering material has a uniform appearance. Preferably, at least one end of the longitudinally extending (e.g., generally cylindrical) core of tobacco smoke filter material has a uniform appearance such that only the tobacco smoke filter material is visible at that end of the core (e.g., such that other components such as additives, channels, etc. are not visible at that end of the core). A uniform end appearance (e.g., an appearance such that only the smoke filtering material is visible at that end of the core) may be advantageous to the smoker.

The tobacco smoke filter material of the longitudinally extending core may be any filamentary material commonly used in tobacco smoke filter manufacture. The filter material may be a natural or synthetic filamentary tow, for example, a cotton or plastic (such as polyethylene or polypropylene), or a cellulose acetate filamentary tow. Preferably, the filter material is a filamentous cellulose acetate tow.

In accordance with the present invention, in one aspect, there is provided a tobacco smoke filter or filter element comprising a longitudinally extending (e.g. generally cylindrical) core of tobacco smoke filter material having a circumference (e.g. perimeter) of 14mm to 17mm (e.g. 16mm to 17 mm); and an additive-releasing container (e.g., a capsule) completely enclosed within the core; wherein the tobacco smoke filter material is a (e.g., filiform) cellulose acetate (e.g., cellulose acetate tow) having a denier per filament of 5.3 or greater and a total denier of 18000 or less.

The specifications of a filamentous tobacco smoke filter material (e.g., a filter material tow) such as cellulose acetate are described in terms of denier per filament (dpf), total denier, and cross-sectional shape of the fiber. Denier per filament is defined as the weight gram of a single filament of 9000 meters; the total denier is simply dpf multiplied by the number of filaments in the filament bundle. Thus, for example, a 5Y30000 tow describes a material having filaments of dpf 5 grams per 9000 meters in a Y-shape, comprising 6000 filaments of total denier given 30000 grams per 9000 meters in length; 5.2Y18000 tow describes a material having filaments of 5.2 grams per 9000 meters of dpf in a Y-shape, comprising about 3500 filaments of given 18000 grams total denier per 9000 meters length; 6.8Y15000 tow describes a material having filaments of 6.8 grams per 9000 meters of dpf in a Y-shape, comprising about 2200 filaments of 15000 grams total denier per 9000 meters length.

The filament material (e.g., filament filter tow, cellulose acetate tow) may have a denier per filament of 5.3 or greater, such as 5.3 to 13, such as 5.3 to 12, such as 5.3 to 9, such as 5.4 to 8, such as 6 to 7. The filament material (e.g., filament filter tow, cellulose acetate tow) may have a denier per filament of from 5.3 to 7.9, from 5.3 to 7.5, such as from 6 to 7.5. The filament material (e.g., filament filter tow, cellulose acetate tow) may have a denier per filament of 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, 7, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9. In examples, the filament material may have a denier per filament of 5.3 or greater, such as 5.4 or greater, such as 5.5 or greater, such as 5.6 or greater, such as 5.7 or greater, such as 5.8 or greater, such as 5.9 or greater, such as 6 or greater, such as 6.1 or greater, such as 6.2 or greater, such as 6.3 or greater, such as 6.4 or greater, such as 6.5 or greater.

The total denier of the filamentary material (e.g., filamentary filter tow, cellulose acetate tow) may be 9000 to 18000, such as 10000 to 18000, such as 12000 to 17000, such as 14000 to 16000. The total denier of the filamentary material (e.g., filamentary filter tow, cellulose acetate tow) may be from 15000 to 18000, such as from 15100 to 18000, such as from 15500 to 17000, such as from 15500 to 16000. The total denier of the filamentary material (e.g., filamentary filter tow, cellulose acetate tow) may be 10000, 11000, 12000, 13000, 14000, 15000, 16000, 17000, 18000. In examples, the total denier of the filamentary material may be 18000 or less, e.g., 17900 or less, e.g., 17800 or less, e.g., 17700 or less, e.g., 17600 or less, e.g., 17500 or less, e.g., 17400 or less, e.g., 17300 or less, e.g., 17200 or less, e.g., 17100 or less, e.g., 17000 or less.

The filamentary material may have any cross-section (e.g., Y-section, X-section, circular section), and those skilled in the art will appreciate that various cross-sections are known in the art. Filiform materials of Y-shaped cross section are preferred.

The additive-releasing container may be a capsule, such as a frangible capsule. The (e.g. friable) capsule may contain additives in the form of flavouring agents. The additive release container [ (e.g., frangible) capsule ] may contain one or more additives, such as flavoring agents and/or liquid materials, solid materials, or other materials, such as activated carbon to aid in the filtration of smoke. The use of additives comprising capsules in filters is well known in the art.

Flavoring agents may be any flavoring agent known or suitable for smoking articles such as cigarettes, for example menthol, spearmint, peppermint, fenugreek, clove and the like. Preferably, the flavoring agent is menthol or comprises menthol. The container (capsule) may contain more than one flavouring agent (and may provide a blend of different flavours, which may or may not contain menthol).

The filter or filter element may contain an additive in the form of a flavouring agent [ e.g. in an additive releasing container (e.g. a frangible) capsule ], wherein the amount of additive (flavouring agent) is less than 35mg (per filter/filter element). The filter or filter element may comprise the additive in the form of a flavouring agent [ e.g. in an additive releasing container (e.g. a frangible) capsule ], wherein the amount of additive (flavouring agent) is from 5mg to 30mg, e.g. from 7mg to 25mg, e.g. from 10mg to 20mg (per filter/filter element).

The width of the additive release container [ (e.g. frangible) capsule ] (the direction perpendicular to the direction in which the longitudinally extending core extends when measured at the widest point in the cross-filter direction) may be from 2.0mm to 4mm, such as from 2.5mm to 3.9mm, such as from 3.0mm to 3.8mm, such as from 3.2mm to 3.7mm, such as 3.5mm. The additive release container [ (e.g., frangible) capsule ] may contain less than 35mg of flavoring agent. The additive release container [ (e.g., frangible) capsule ] may contain from 5mg to 30mg, e.g., 7mg to 25mg, e.g., 10mg to 20mg of flavoring agent.

The length of the filter or filter element may be from 10mm to 30mm, for example from 14mm to 27mm, for example from 17mm to 25mm.

As set forth in example 1 below, the applicant produced ultrafine filters without capsules to determine minimum, maximum and optimum tow weights for the relevant filter sizes, and then produced corresponding filters with capsules in order to evaluate the effect of the capsules on pressure drop. Unexpectedly, the applicant found that: the inclusion of capsules in a filter comprising a core of filiform filter material (e.g. cellulose acetate tow) having a denier per filament of 5.3 or more (e.g. 6.8) and a total denier of 18000 or less (15000) is only associated with a relatively small increase in pressure drop. This suggests that filiform filter materials (e.g. cellulose acetate tow) having a denier per filament of 5.3 or more (e.g. 6.8) and a total denier of 18000 or less (15000) may be particularly suitable for use in ultra-fine filters or microfilters comprising capsules.

The filter element according to the invention can be used as a segment of a multi-segment fine filter, such as a two-segment filter, a three-segment filter, or other multi-segment filter. Such filters are well known in the art. If the filter element is used as or in a section of a multi-section filter, the filter element may be used at (or in) the mouth end or mouth end section of the filter, or as (or in) any other section of the filter. If the filter element is used as or in a section of a multi-section filter, the other sections may be, for example, wrapped or unwrapped acetate sections, sections containing particulate additives or liquid additives such as activated carbon or flavorants (e.g., active acetate filter sections, flavor wire filter sections (flavour thread filter segment)), sections containing paper or nonwoven materials, other sections containing capsules, and the like. The filter element according to the invention can itself be used, for example, as a single-stage ultrafine filter or as a microfilter (for example in the same way as a monoacetate filter).

The filters of the invention may be packaged and sold for use in self-wrapping (Roll Your Own) or self-made (Make Your Own) smoking articles, such as self-wrapping cigarettes. The filter can be in the form of Pop-a-Tip ^TM Filters, which are known and available from Filtrona Filters, are packaged in a similar manner for use by self-Rolling (RYO) smokers. The type of Pop-a-Tip filter comprises a series of filters (filters) wrapped in a transparent film made of BOPP or cellophane, for example. The filter is individually pushed out (or "popped out") of the transparent wrapper by the smoker of the RYO product, who then causes them to roll their cigarettesA filter is used. According to the present invention there is provided in a further aspect a product bar comprising: a plurality (e.g., two or more, such as 4 to 6) individual tobacco smoke filters according to any aspect of the invention (or a plurality of individual tobacco smoke filters comprising filter elements according to any aspect of the invention) contiguous end-to-end; and a (common) wrap engaged around the plurality of filters or filter elements. The common wrapper may be a transparent material made of BOPP or cellophane, for example.

In a filter cigarette according to the invention, the filter of the invention (or a filter comprising a filter element of the invention) is attached to a wrapped tobacco rod with the end of the filter facing the tobacco. The filter may be attached to the wrapped tobacco rod by annular end fitting (which is engaged only around the adjacent ends of the (wrapped) filter and rod so that most of the filter wrap is exposed). The filter may be connected by a fully end-tipping overwrap (full tipping overwrap) which is joined around the entire filter length and adjacent ends of the tobacco rod.

The filter, filter element or filter cigarette according to the invention may be ventilated by methods known in the art, for example by using a pre-perforated or air-permeable wrap, and/or laser perforation of the wrap and, if present, the end-tipping overwrap. The vented full end-tipping overwrap may also be inherently breathable or provided with ventilation holes, and in a vented product in which both the wrapper and the end-tipping overwrap are present, ventilation through the overwrap will normally (and preferably) be aligned with ventilation through the wrapper (tipping paper). As is well known in the art, ventilation holes through the wrap of the filter, or through the end-tipping overwrap, or both, may be made by laser perforation during the filter or filter cigarette production.

According to the present invention, in a further aspect there is provided a multi-section wand comprising a plurality (e.g. 2, 4, 6, etc.) of filters (or filter elements) as described above and/or herein, said filters (or filter elements) being integrally connected end-to-end in mirrored relation.

Drawings

The invention will now be illustrated with reference to the accompanying drawings, in which:

fig. 1 is a view of a tobacco smoke filter according to an example of the present invention;

fig. 2 is a view of the tobacco smoke filter of fig. 1 with portions cut away to show the interior of the filter;

FIG. 3 shows a plot of the capacity of 5.2Y18000 tow as described in example 1 below, and

fig. 4 shows the capacity curve of 6.8Y15000 described in example 1 below.

Detailed Description

The filter 1 shown in figure 1 (and figure 2) comprises a longitudinally extending generally cylindrical core 2 of tobacco smoke filtering material of circumference 16.8mm and length 27 mm. (in fact, the perimeter of the core 2 is 16.8mm, since the cylindrical core 2 has a circular cross section). The filter material was 6.8Y15000 filiform strands of filiform cellulose acetate. The filter 1 further comprises a wrapper 3 of tipping paper (plugwrap), which wrapper 3 is joined around the longitudinally extending core 2 and held in place by overlapping and bonded seams, as is well known in the art.

The filter 1 further comprises an additive release container in the form of a frangible capsule 5 containing a flavouring agent, the frangible capsule 5 being fully enclosed within the cylindrical core 2; the filter material completely encapsulates the capsule. This may be best seen in fig. 2 (which shows a cross-sectional view of the filter and capsule), but the position of the capsule 5 within the core 2 is also shown in fig. 1 by means of a dashed line 5 a. The additive releasing container is a spherical capsule 5 of 3.5mm diameter comprising a breakable outer shell 6 of gelatin or the like, the spherical capsule 5 enclosing a menthol-coated liquid 7. Such frangible or breakable spherical capsules 5 containing flavoring agents and their method of manufacture are well known in the art.

Methods for manufacturing filters including capsules are well known. It is known to manufacture longitudinally extending filter rods from a filiform filter material such as cellulose acetate tow by the steps of: the cellulose acetate filaments are pulled from the source, the longitudinally advancing filaments are gathered (e.g., by passing through a nozzle), and the gathered/compressed filaments are advanced through a reinforcement (garniture) where the newly formed longitudinally extending rod of filter material is wrapped in tipping paper and the tipping paper is held in place by overlapping and bonded seams. The longitudinally advancing rod may be cut into individual filters or, more typically, into multiple sections of rods comprising multiple (e.g., 2, 4, 6, etc.) filters. The method may be adapted to make a filter containing capsules by including in the process a machine for inserting capsules (such machines are well known). In one such machine, the (spherical) capsules 5 are held in a stacked fashion and fed continuously into the longitudinally advancing filamentary cellulose acetate tow as it is gathered, whereby the advancing tow is gathered and compressed around the capsules 5 as it passes through the nozzle and into the reinforcement. The resulting longitudinally advancing rod (containing capsules) is cut into filters/rods in the usual manner.

The filter of fig. 1 may be attached to a wrapped tobacco rod (not shown) by methods known in the art with the end of the filter facing the tobacco. The filter may be connected to the wrapped tobacco rod by an annular end fitting which engages around only the wrapped filter 1 and the adjacent end of the rod leaving most of the wrap 3 exposed, or the filter may be connected by means of a full end fitting overwrap which engages around the full length of the filter 1 and the adjacent end of the tobacco rod.

Example 1-test for manufacturing ultra-fine capsule filters

Multiple length "single" filter rods are made by methods known in the art. Each multiple length filter rod includes a longitudinally extending generally cylindrical core of filamentous cellulose acetate having a length of 108mm and a perimeter of 16.8 mm. It will be appreciated that the rod is a multi-section rod which can be cut into four 27mm long filters (so-called "4-minute" rods). Two different cellulose acetate filter tow were used: 5.2Y18000 and 6.8Y15000. As is known, the first number (5.2 or 6.8) refers to the denier per filament, Y refers to the filament cross-sectional shape, and the second number (15000 or 18000) refers to the total denier of the filament bundle.

The single filter/filter rod without capsules described above was evaluated to determine minimum, maximum and optimum tow weights for these filter sizes, enabling the so-called "tow capability curves" to be plotted. Such curves are well known to those skilled in the art. These three points for a "single" rod have been determined (and also confirmed that these values are consistent with those predicted by the standard modeling program "virtual tow selector"), the corresponding rod having 4 evenly spaced capsules (spherical shape, 3.5mm diameter) per 108mm rod, one for each filter in the rod, to evaluate the effect of the capsules on the pressure drop across the filters.

Tables 1 and 2 below show the results of the pressure drop resistance of "single" filter rods, including the 5.2Y18000 tow (table 1) and 6.8Y15000 tow (table 2) evaluated later, and the filter rods comprising capsules, and these data are also graphically depicted in fig. 3 and 4.

The minimum point is determined based on the weight of the tow giving a 1mm groove in the finished rod (i.e., the tow "bounces" after cutting to give the disc-shaped end of the finished filter/rod). The maximum point is determined by the weight of the tow that produces a coefficient of variation in pressure drop of about 6%, with higher variation values generally being considered unacceptable. The tow weight is input into a virtual tow selector program to determine the "percent capacity" shown in the table. 5.2Y18000 tow project provides a range of-1% to 36% capacity. 6.8Y15000 tow project produced a range of capacities from 0% to 70%.

Tables 1-5.2Y18000 tow results

Tables 2-6.8Y15000 tow results

* Correction was made for the perimeter differences and 4 filters per rod.

Pressure drop is a critical parameter in filter design. The decision criteria for the range of available pressure drops are typically based on those data points that yield a coefficient of variation of 6% or less from the tow item. Thus, available pressure drops for capsule filters using these tows were found to range from 270mm to 380mm water column for 6.8Y15000 tows and from 480mm to 550mm water column for 5.2Y18000 tows. Use of these tows outside of these ranges may result in poor performance or poor product performance (i.e., the tows are difficult to manufacture or perform poorly).

As expected, the addition of the capsules caused an increase in the pressure drop across the rod. 5.2Y18000 tow sees an increase in average pressure drop per filter of 33mm (based on the result of 108mm/4 rod) while the average filter PD for 6.8Y15000 tow is only 18mm.

Thus, unexpectedly, the applicant found that: the inclusion of capsules in a filter comprising a core of filiform filter material (e.g. cellulose acetate tow) having a denier per filament of 5.3 or more (e.g. 6.8) and a total denier of 18000 or less (e.g. 15000) is only associated with a relatively small increase in pressure drop. This suggests that filiform filter materials (e.g., cellulose acetate tow) having a denier per filament of 5.3 or greater (e.g., 6.8) and a total denier of 18000 or less (e.g., 15000) may be particularly suitable for use in ultra-fine filters or microfilters comprising capsules.

The invention provides the following technical scheme:

scheme 1. A tobacco smoke filter or filter element comprising: a longitudinally extending core of tobacco smoke filter material having a circumference of 14mm to 17 mm; and an additive-releasing container completely enclosed within the core; wherein the filter material is a filiform material having a denier per filament of 5.3 or more and a total denier of 18000 or less.

The tobacco smoke filter or filter element of aspect 1, wherein the longitudinally extending core of tobacco smoke filtering material is a generally cylindrical core of tobacco smoke filtering material.

Solution 3 the tobacco smoke filter or filter element of solution 1 or 2 wherein the longitudinally extending core of tobacco smoke filtering material has a circumference or perimeter of 16mm to 17mm.

The tobacco smoke filter or filter element of any preceding aspect, further comprising a wrapper engaged around the longitudinally extending core.

A tobacco smoke filter or filter element according to any preceding claim wherein the filter material is a filamentary cellulose acetate tow.

A tobacco smoke filter or filter element according to any preceding claim wherein the filament material has a denier per filament of from 5.3 to 13, such as from 5.3 to 9, such as from 5.4 to 8, such as from 6 to 7.

A tobacco smoke filter or filter element according to any preceding claim, wherein the total denier of the filamentary material is from 9000 to 18000, for example from 10000 to 18000, for example from 12000 to 17000, for example from 14000 to 16000.

A tobacco smoke filter or filter element comprising a longitudinally extending core of tobacco smoke filtering material having a circumference of 14mm to 17 mm; and an additive-releasing container completely enclosed within the core; wherein the tobacco smoke filter material is cellulose acetate having a denier per filament of 5.3 or greater and a total denier of 18000 or less.

The tobacco smoke filter or filter element of claim 8, wherein the longitudinally extending core of tobacco smoke filtering material is a generally cylindrical core of tobacco smoke filtering material.

The tobacco smoke filter or filter element of claim 8 or 9, wherein the perimeter or perimeter of the longitudinally extending core of tobacco smoke filtering material is 16mm to 17mm.

The tobacco smoke filter or filter element of claim 8, 9, or 10 further comprising a wrapper engaged around the longitudinally extending core.

A tobacco smoke filter or filter element according to any one of claims 8 to 11 wherein the cellulose acetate has a denier per filament of 5.3 to 13, such as 5.3 to 9, such as 5.4 to 8, such as 6 to 7.

A tobacco smoke filter or filter element according to any one of claims 8 to 12 wherein the cellulose acetate has a total denier of 9000 to 18000, such as 10000 to 18000, such as 12000 to 17000, such as 14000 to 16000.

A tobacco smoke filter or filter element according to any preceding claim wherein the additive release container is a capsule, such as a frangible capsule.

A tobacco smoke filter or filter element according to any preceding claim wherein the additive release container comprises an additive in the form of a flavouring agent.

A tobacco smoke filter or filter element according to any preceding claim wherein the additive release container has a width of from 2.0mm to 4mm, for example from 3.2mm to 3.7mm, for example 3.5mm.

Scheme 17 a tobacco smoke filter or filter element substantially as hereinbefore described with reference to figures 1 and 2 of the accompanying drawings.

A filter cigarette comprising a filter according to any preceding claim or a filter comprising a filter element according to any preceding claim, the filter being attached to a wrapped tobacco rod with one end of the filter facing the tobacco.

Solution 19. A multi-section rod comprising a plurality of filters or filter elements according to any of the preceding solutions connected end-to-end.

Scheme 20. A product bar comprising: a plurality of individual tobacco smoke filters according to any one of claims 1 to 19, or a plurality of individual tobacco smoke filters comprising filter elements according to any one of claims 1 to 19, abutting end-to-end; and a wrapper engaged around the plurality of filters.

Claims

1. A tobacco smoke filter or filter element comprising: a longitudinally extending core of tobacco smoke filter material having a circumference of 14mm to 17 mm; and an additive-releasing container completely enclosed within the core; wherein the filter material is a filiform material having a denier per filament of 5.3 or more and a total denier of 18000 or less.

2. A tobacco smoke filter or filter element according to claim 1 wherein the longitudinally extending core of tobacco smoke filtering material is a generally cylindrical core of tobacco smoke filtering material.

3. A tobacco smoke filter or filter element according to claim 1 or claim 2 wherein the longitudinally extending core of tobacco smoke filtering material has a circumference or perimeter of from 16mm to 17mm.

4. A tobacco smoke filter or filter element according to any preceding claim further comprising a wrapper engaged around the longitudinally extending core.

5. A tobacco smoke filter or filter element according to any preceding claim wherein the filter material is a filamentary cellulose acetate tow.

6. A tobacco smoke filter or filter element according to any preceding claim wherein the filament material has a denier per filament of from 5.3 to 13, such as from 5.3 to 9, such as from 5.4 to 8, such as from 6 to 7.

7. A tobacco smoke filter or filter element according to any preceding claim wherein the total denier of the filamentary material is 9000 to 18000, such as 10000 to 18000, such as 12000 to 17000, such as 14000 to 16000.

8. A tobacco smoke filter or filter element comprising a longitudinally extending core of tobacco smoke filtering material having a circumference of 14mm to 17 mm; and an additive-releasing container completely enclosed within the core; wherein the tobacco smoke filter material is cellulose acetate having a denier per filament of 5.3 or greater and a total denier of 18000 or less.

9. A tobacco smoke filter or filter element according to claim 8 wherein the longitudinally extending core of tobacco smoke filtering material is a generally cylindrical core of tobacco smoke filtering material.

10. A tobacco smoke filter or filter element according to claim 8 or 9 wherein the circumference or perimeter of the longitudinally extending core of tobacco smoke filtering material is from 16mm to 17mm.

11. A tobacco smoke filter or filter element according to claim 8, 9 or 10 further comprising a wrapper engaged around the longitudinally extending core.

12. A tobacco smoke filter or filter element according to any one of claims 8 to 11 wherein the cellulose acetate has a denier per filament of from 5.3 to 13, such as from 5.3 to 9, such as from 5.4 to 8, such as from 6 to 7.

13. A tobacco smoke filter or filter element according to any one of claims 8 to 12 wherein the cellulose acetate has a total denier of 9000 to 18000, such as 10000 to 18000, such as 12000 to 17000, such as 14000 to 16000.

14. A tobacco smoke filter or filter element according to any preceding claim wherein the additive release container is a capsule, such as a frangible capsule.

15. A tobacco smoke filter or filter element according to any preceding claim wherein the additive release container contains an additive in the form of a flavouring agent.

16. A tobacco smoke filter or filter element according to any preceding claim wherein the additive release container has a width of from 2.0mm to 4mm, such as from 3.2mm to 3.7mm, such as 3.5mm.

17. A tobacco smoke filter or filter element substantially as hereinbefore described with reference to figures 1 and 2 of the accompanying drawings.

18. A filter cigarette comprising a filter according to any preceding claim or a filter comprising a filter element according to any preceding claim, the filter being connected to a wrapped tobacco rod, wherein one end of the filter is directed towards the tobacco.

19. A multi-section rod comprising a plurality of filters or filter elements according to any preceding claim connected end to end.

20. A product bar, comprising: a plurality of individual tobacco smoke filters according to any one of claims 1 to 19, or a plurality of individual tobacco smoke filters comprising filter elements according to any one of claims 1 to 19, abutting end-to-end; and a wrapper engaged around the plurality of filters.