WO2015197674A1

WO2015197674A1 - Tobacco smoke filter

Info

Publication number: WO2015197674A1
Application number: PCT/EP2015/064223
Authority: WO
Inventors: James Reed; Philip WATKINSON
Original assignee: Essentra Filter Products Development Co. Pte. Ltd; Essentra Filter Products Limited
Priority date: 2014-06-26
Filing date: 2015-06-24
Publication date: 2015-12-30
Also published as: GB201411372D0

Abstract

There is disclosed a tobacco smoke filter or filter element comprising: a longitudinally extending core of tobacco smoke filtering material; at least one receptacle for an additive located in the longitudinally extending core; and at least one continuous element which extends through the longitudinally extending core from one end of the core to the other end of the core, wherein the longitudinally extending core has a length I and the (or each) continuous element has a length L, wherein L is greater (longer) than I. Also disclosed are methods and apparatus for making tobacco smoke filters and elements, and smoking articles containing tobacco smoke filters and elements.

Description

TOBACCO SMOKE FILTER

The present invention relates to tobacco smoke filters for smoking articles such as cigarettes, in particular filters which include one or more (e.g. flavour containing) frangible capsules, together with one or more continuous elements [e.g. one or more threads (such as flavour threads), tapes, filaments or extruded strands].

Tobacco smoke filters which include a frangible capsule, or a plurality of frangible capsules, are well-known. Similarly, tobacco smoke filters with a thread, or plurality of threads, running along their longitudinal axis are also well-known. Flavours may be applied to the filters incorporating these threads (either directly to the thread, or via a separate application route), in which case they can be known as 'Flavour Thread Filters'. However, there are very few disclosures of cigarette filters that incorporate both a thread and a capsule. WO 2013/098957 discloses a triple cavity filter with a capsule in a central cavity and a thread or similar in the downstream segment (i.e. in a separate section of the filter to the capsule) that can be used to provide an indication that the capsule has been ruptured (through wicking means). WO 2013/124377 discloses a single section filter with a capsule linked to a thread, again to provide a visual indication to the smoker of capsule breakage. It is clear from the description (e.g. see figure 7 of WO 2013/124377) that this requires the inclusion of 'capsules-on-a-string' - i.e. a preformed continuous array of capsules at spaced intervals that are linked by, and formed integrally with, thread-like members.

It would be highly desirable to produce a filter including discrete, separated, capsules and a separate thread (or threads) running longitudinally along the filter. This would provide much greater design flexibility in the choice of thread and capsule - e.g. in terms of size, flavour(s), positioning, colour(s), etc. - than a preformed array. However, this has previously not been possible to achieve due to interference between the respective current processes for inserting capsules and inserting longitudinal threads. The current invention overcomes these process limitations and identifies advantageous properties of the products so-formed.

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. substantially cylindrical) core of tobacco smoke filtering material;

at least one receptacle (e.g. capsule, e.g. a frangible capsule) for an (e.g. a first) additive (e.g. a (first) flavouring agent) located in (e.g. fully enclosed within) the

longitudinally extending (e.g. substantially cylindrical) core; and

at least one continuous element which extends through the longitudinally extending (e.g. substantially cylindrical) core from one end of the core to the other end of the core, wherein the longitudinally extending (e.g. substantially cylindrical) core has a length I and the (or each) continuous element (which extends through the longitudinally extending core) has a length L, wherein L is greater (longer) than I.

The (or each) continuous element (which extends through the longitudinally extending core from one end of the core to the other end of the core) is fully enclosed within the longitudinally extending (e.g. substantially cylindrical) core, apart from at each end of the longitudinally extending core (where it is exposed). Thus, the (or each) continuous element is only visible at the ends of the longitudinally extending (e.g.

substantially cylindrical) core. Herein the term "continuous element" means a single element (a thread, continuous extruded element etc.) which extends through the longitudinally extending (e.g. substantially cylindrical) core from one end of the core to the other end of the core and which does not have gaps or breaks (or joints or junctions) along its length.

The longitudinally extending core has length I and the (or each) continuous element has length L, where length L is greater (longer) than length I. In other words, the (or each) continuous element is longer than the longitudinally extending core through which it extends, such that the (or each) continuous element does not extend in a straight line through the longitudinally extending core from one end of the core to the other end (of the core). The (or each) continuous element may include one or more bends, kinks or the like [e.g. so that the full length L of the (or each) continuous element (which is greater than I) is accommodated within the full (but shorter) length I of the longitudinally extending core through which it extends]. The (or each) continuous element may follow a bent, kinked or curved path (e.g. a wave or wavy path or pattern, e.g. a sinusoidal wave path or pattern) through the longitudinally extending core from one end of the core to the other end (of the core). Preferably, the (or each) continuous element follows a curved path through the longitudinally extending core [from one end of the core to the other end (of the core)] such that the continuous element extends or bends around the (or each) receptacle. When a continuous element (e.g. thread) and capsule(s) are combined in such a pattern it enables the continuous element to be centrally located at the ends of the core and the capsule(s) to be centrally located in the body of the filter (with the continuous element following a curved path through the longitudinally extending core, e.g. with the continuous element following a curved path bending around the receptacles in the core). This provides superior end appearance (for eye appeal or anti-counterfeiting measures), while ensuring that the capsules are centrally located within the filter/element, which facilitates even capsule breakage and distribution of flavour. Herein the term "centrally located" means located at the centre point of a section of the longitudinally extending core taken perpendicular to the longitudinal axis of the core. Thus, where a continuous element is "centrally located" at the ends of the core, this means that the continuous element is located at the centre point of each (e.g. circular) end of the core, each end being a section of the longitudinally extending core taken perpendicular to the longitudinal axis of the core (at that end).

In examples of this aspect of the invention, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.01 x or greater than 1.01x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element. Thus, if the length I of the longitudinally extending (e.g.

substantially cylindrical) core of the filter or filter element is 20mm, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.01x20 mm (20.2mm), or greater than 1.01x 20 mm (greater than 20.2mm); in other words, if the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element is 20mm, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 20.2mm or greater. Preferably, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.1 x or greater than 1.1x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element. Thus, if the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element is 20mm, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.1x20 mm (22mm), or greater than 1.01x 20 mm (greater than 22mm). More preferably, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.2x or greater than 1.2x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element.

In examples of this aspect of the invention, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be up to 1.5x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element.

Advantageously, the filters of this aspect of the invention enclose a longer continuous element than conventional thread filters (where the thread extends in a straight line through the filter), which allows greater loading of flavour on the continuous element (if desired).

The tobacco smoke filter or filter element may be of length 12 to 40 mm, e.g. 15 to 35 mm, e.g. 20 to 30 mm. Thus, the length I of the longitudinally extending (e.g.

substantially cylindrical) core of the filter or filter element may be of length 12 to 40 mm, e.g. 15 to 35 mm, e.g. 20 to 30 mm. The length L of the (or each) continuous element

(which extends through the longitudinally extending core) may be 15 to 50 mm, e.g. 20 to

43 mm, e.g. 23 to 35 mm (depending on the length I of the core through which it extends).

It will be appreciated that in this aspect of the invention, for a given filter/filter element, the length L is always greater (longer) than the length I. The tobacco smoke filter (or filter element) may be of circumference 14 to 28 mm, for example 16 to 26mm, for example 16 to 17 mm or 24 to 25 mm.

In this aspect, it is preferred that the continuous element(s) is not formed integrally with the receptacle(s). In other words, it is preferred that the receptacles (e.g. capsules, e.g. frangible capsules) for additive are separate to (i.e. not formed as part of, not of unitary construction with) the continuous element.

The applicants have found that filters and filter elements of the invention, which may be made by the methods described herein, are advantageous because they (and the associated method) provide greater flexibility in terms of design selection for capsule and continuous element (e.g. thread) than 'capsule-on-thread' designs such as WO

2013/124377, because the continuous element and the receptacle are separate from each other.

According to the present invention in a further aspect there is provided a tobacco smoke filter or filter element comprising:

longitudinally extending (e.g. substantially cylindrical) core; and

two or more (e.g. two to four, 2, 3 or 4) continuous elements which extend through the longitudinally extending (e.g. substantially cylindrical) core from one end of the core to the other end of the core.

In examples of this aspect of the invention, the longitudinally extending (e.g.

substantially cylindrical) core has a length I and the (or each) continuous element (which extends through the longitudinally extending core) has a length L, wherein length L is equal to or greater (longer) than length I. It will be appreciated that more than one (e.g. 2-4) threads may be inserted into the filter using derivations of the process described below. When more than one thread is present, the need for the continuous element to follow a 'wave' path around the receptacles is reduced (or even eliminated), because there is less need for the continuous element to be centrally located at the ends of the longitudinally extending (e.g. substantially cylindrical) core of the finished filter. The applicants have found that filters and filter elements of the invention, which may be made by the methods described herein, are advantageous because they (and the associated method) provide greater flexibility in terms of design selection for capsule and continuous element (e.g. thread) than 'capsule-on-thread' designs such as WO 2013/124377, because the continuous element and the receptacle are separate from each other.

substantially cylindrical) core of the filter or filter element is 20mm, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.01x20 mm (20.2mm), or greater than 1.01x 20 mm (greater than 20.2mm); in other words, if the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element is 20mm, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 20.2mm or greater. Preferably, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.1 x or greater than 1.1x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element. Thus, if the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element is 20mm, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.1x20 mm (22mm), or greater than 1.01x 20 mm (greater than 22mm). More preferably, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.2x or greater than 1.2x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element. In examples of this aspect of the invention, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be up to 1.5x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element.

a longitudinally extending (e.g. substantially cylindrical) core of tobacco smoke filtering material; at least one receptacle (e.g. capsule, e.g. a frangible capsule) for an (e.g. a first) additive (e.g. a (first) flavouring agent) located in (e.g. fully enclosed within) the

longitudinally extending (e.g. substantially cylindrical) core; and

at least one continuous element which extends through the longitudinally extending (e.g. substantially cylindrical) core from one end of the core to the other end of the core, wherein the continuous element(s) is not formed integrally with the receptacle(s). In this aspect the receptacles (e.g. capsules, e.g. frangible capsules) for additive are separate to (i.e. not formed as part of, not of unitary construction with) the continuous element.

In examples of this aspect of the invention, the longitudinally extending (e.g.

substantially cylindrical) core has a length I and the (or each) continuous element (which extends through the longitudinally extending core) has a length L, wherein length L is greater (longer) than length I.

In examples of this aspect of the invention, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.01x or greater than 1.01x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element. Thus, if the length I of the longitudinally extending (e.g.

substantially cylindrical) core of the filter or filter element is 20mm, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.01x20 mm (20.2mm), or greater than 1.01x 20 mm (greater than 20.2mm); in other words, if the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element is 20mm, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 20.2mm or greater. Preferably, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.1 x or greater than 1.1x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element. Thus, if the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element is 20mm, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1.1x20 mm (22mm), or greater than 1.01x 20 mm (greater than 22mm). More preferably, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be 1 2x or greater than 1.2x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element. In examples of this aspect of the invention, the length L of the (or each) continuous element (which extends through the longitudinally extending core) may be up to 1.5x the length I of the longitudinally extending (e.g. substantially cylindrical) core of the filter or filter element.

The applicants have found that filters and filter elements of this aspect of the invention, which may be made by the methods described herein, are advantageous because they (and the associated method) provide greater flexibility in terms of design selection for capsule and continuous element (e.g. thread) than 'capsule-on-thread' designs such as WO 2013/124377, because the continuous element and the receptacle are separate from each other.

The longitudinally extending (e.g. substantially cylindrical) core comprises tobacco smoke filtering material. The tobacco smoke filtering material may be, for example, any of those materials (usually filamentary, fibrous, web or extruded) which are conventionally employed for tobacco smoke filter manufacture. The tobacco smoke filtering material may be, for example, natural or synthetic filamentary tow, e.g. of cotton or plastics such as polyethylene or polypropylene, or cellulose acetate filamentary tow. It may comprise, for example, natural or synthetic staple fibres, cotton wool, a web material such as paper (usually creped), an (e.g. synthetic) non-woven material, and/or an extruded material (e.g. starch, synthetic foams, extruded foams).

Preferably, the filtering material is cellulose acetate (e.g. in the form of a filamentary tow). The filtering material may be cellulose acetate to which a plasticiser has been applied (e.g. plasticised filamentary tow). Triacetin is, as is well known in the art, and typically applied to cellulose acetate filters as a plasticiser (e.g. at around 6-8% w/w).

The (or each) receptacle (e.g. capsule, e.g. frangible capsule) for the (e.g. first) additive is located in (e.g. is fully enclosed within) the longitudinally extending (e.g.

substantially cylindrical) core. Preferably the receptacle is a capsule, for example a frangible capsule. Frangible or breakable capsules for filters are well known in the art. The frangible or breakable capsule may include a frangible/breakable outer layer or shell which surrounds the (e.g. first) additive [e.g. a (e.g. first) flavouring agent]. The (e.g. first) additive [e.g. a (e.g. first) flavouring agent] may be in the form of a liquid, such that the additive is held within the outer layer/shell (e.g. within an enclosure defined by the inner surface of the outer layer/shell). The outer layer/shell of the capsule may comprise gelatin. The outer layer/shell may comprise one or more of gelatin, gellan gum, agar, an alginate, a carrageenan, a pectin, arabic gum, ghatti gum, pullulan gum, mannan gum or modified starch. The thickness of the outer layer (shell) of the capsule may be 10-500 microns, preferably 30-150 microns, more preferably 50-80 microns. The outer diameter of the capsule may be 2 to 8 mm, for example 3 to 7 mm, for example 3 to 5 mm, for example 3.5 to 4.5 mm.

Preferably the (e.g. first) additive (in the receptacle) is a (e.g. first) flavouring agent. Preferably the first additive is in the form of a liquid. The (e.g. first) flavouring agent may be any flavouring agent known for use in tobacco smoke filters or filter elements. For example, the flavouring agent may be menthol, spearmint, peppermint, nutmeg, cinnamon, clove, lemon, chocolate, peach, strawberry, vanilla etc. The (e.g. first) additive [e.g.

flavouring agent] may contain nicotine or a salt or derivative thereof. Preferably the (first) flavouring agent contains menthol.

The (or each) continuous element may be, for example, a thread or tape element, as are well known in the art e.g. a cotton thread. The (or each) continuous element may be a woven natural fibre (e.g. cotton), woven synthetic fiber (e.g. nylon, polyester, cellulose acetate), etc. The (or each) continuous element may be a continuous extruded element, as described below. The (or each) continuous element is not (e.g. formed from) a tobacco smoke filtering material. In other words, the (or each) continuous element is a separate entity to the tobacco smoke filtering material.

The continuous element (thread, tape, continuous extruded element, etc.) may be of diameter 0.25 -3.0mm.

The (or each) continuous element (thread, tape, continuous extruded element, etc.) may be coloured or pigmented. The (or each) continuous element (thread, tape, continuous extruded element, etc.) may be coloured or tinted using appropriate pigments, preferably those with regulatory approval for use in food contact applications. The pigment(s) may preferably be any colour which contrasts with the (e.g. white) tobacco smoke filtering material, for example green, blue, red, orange etc. A coloured continuous element (or coloured continuous element if more than one is present) may provide a distinctive end appearance that is useful for anti-counterfeit purposes. It will be

appreciated that if more than one continuous element is present, any continuous element may be of different type (thread, strip, extruded element) to the other element(s), and/or of different colour to the other element(s).

The (or each) continuous element may include an additive (e.g. element additive) on or in the continuous element. Preferably the (e.g. element) additive is a flavouring agent. The element flavouring agent may be any flavouring agent known for use in tobacco smoke filters or filter elements. For example, the (e.g. element) flavouring agent may be menthol, spearmint, peppermint, nutmeg, cinnamon, clove, lemon, chocolate, peach, strawberry, vanilla etc. The (e.g. element) additive [(e.g. element) flavouring agent] may contain nicotine or a salt or derivative thereof. Preferably the flavouring agent contains menthol. The additive (flavouring agent) in the receptacle, and the (e.g. element) flavouring agent(s) if present may be the same or different.

Herein the term "continuous extruded element" means a single element formed by extrusion. The continuous extruded element may be of any cross-sectional shape, thereby providing a much greater distinctive end appearance for e.g. anti-counterfeiting measures. The continuous extruded element may comprise a thermoplastic polymer, for example, cellulose acetate, polyethylene, polypropylene, polylactic acid, polyester or mixture thereof. Preferably the continuous extruded element comprises cellulose acetate. Methods of preparing extrusion grade cellulose acetate powder are known (e.g. see US4,228,246). Extrusion grade cellulose ester pellets are commercially available from Rotuba Extruders of Lindon, New Jersey, under trade mark "NATURACELL". Continuous extruded elements, and their use in tobacco smoke filters, are well known in the art (see e.g.

WO201 1/058319). The (or each) continuous extruded element may be of circular cross- section, star shape cross-section, trilobal cross-section, pentagonal or cog-shaped cross section, or of a cross-section in the shape of a logo or other pattern. The (or each) continuous extruded element may be a tubular element, for example cylindrical (i.e. a continuous extruded hollow tubular element of a circular cross-section) or a continuous extruded hollow tubular element of other (non-circular) cross section (e.g. hollow star- shaped, hollow trilobal, hollow pentagonal, or hollow cog-shaped cross section, or of a hollow cross-section in the shape of a logo or other pattern).

The filter or filter element may comprises a further additive [e.g. (further) flavouring agent] located (e.g. disposed, e.g. dispersed) on and/or in the tobacco smoke filtering material. Preferably the further additive is a (further) flavouring agent. The further flavouring agent may be any flavouring agent known for use in tobacco smoke filters or filter elements. For example, the further flavouring agent may be menthol, spearmint, peppermint, nutmeg, cinnamon, clove, lemon, chocolate, peach, strawberry, vanilla etc. The further additive [e.g. (further) flavouring agent] may contain nicotine or a salt or derivative thereof. Preferably the further flavouring agent contains menthol. The additive (flavouring agent) in the receptacle, and the further flavouring agent(s) may be the same or different.

The further additive [e.g. (further) flavouring agent] may be applied to the tobacco smoke filtering material by feeding or injection into the tobacco smoke filtering material (e.g. by feeding or injecting the flavouring agent into the gathered tow band via a delivery wheel, for example as described and illustrated below). In another example, the further additive [e.g. (further) flavouring agent] may be applied to the tobacco smoke filtering material as a solution comprising the further additive [e.g. (further) flavouring agent] dissolved in a plasticiser. The plasticiser may be any plasticiser, for example any plasticiser which is known for use with a tobacco smoke filtering material. Preferably the plasticiser is triacetin. Preferably the solution comprises further additive [e.g. (further) flavouring agent] dissolved in the plasticiser (e.g. triacetin) wherein the concentration of plasticiser (e.g. triacetin) in the solution is 5% to 40%, preferably 10% to 30%, more preferably 20% (plasticiser).

2013/124377, because the continuous element and the receptacle are separate from each other. The products and methods of the invention allow: (i) enablement of wicking of flavours contained within the capsule along the length of the filter (along the continuous element), for example resulting in more rapid transfer of flavour to the mouth end or providing a colour change to take place (when suitable colour-change agents are present in the thread), through use of a one-step process which leads to separate capsules and continuous elements, rather than the more complex, conventional, multi-segment products or "capsule on thread" designs; (ii) provision of an indication when a capsule has inadvertently been broken prior to smoking (which may provoke a colour change); (ii) use in anti-counterfeit products where a certain colour change can denote an authentic product; (iv) use of types or colours of thread to denote different types of capsule contained within the filter; and/or (iv) application of additional flavours, or increased loading of the same flavour, to a capsule product, e.g. as a flavour boost.

A filter according to any aspect of the invention may further comprise a wrapper engaged around the longitudinally extending (e.g. substantially cylindrical) core. The wrapper may be a paper, e.g. plugwrap paper. The wrapper may be coated to minimise absorption of liquids released from the ruptured capsule, as is well-known in the art. The wrapper may include a still further flavouring agent located thereon, which may be any flavouring agent known for use in tobacco smoke filters or filter elements (e.g. the flavouring agent may be menthol, spearmint, peppermint, nutmeg, cinnamon, clove, lemon, chocolate, peach, strawberry, vanilla etc.).

A filter according to any aspect of the invention may be used on its own e.g. as a single segment filter. Such filters are well known in the art. A filter element according to any aspect of the invention may be used as a segment, for example the mouth end segment, of a multi-segment filter, e.g. a dual, triple, or other multiple filter. A filter element according to any aspect of the invention may be used as another e.g. upstream segment, of a multi-segment filter - for example the tobacco end segment, middle segment etc. of a multi-segment filter, e.g. a dual, triple, or other multiple filter. Multi-segment filters are well known in the art. The other elements of the multi-segment filter - e.g. those which are not according to the invention - may comprise activated carbon or other particulate additive(s), flavouring agent(s) etc.. Filters according to any aspect of the invention, or filters incorporating a filter element according to any aspect of the invention, may be used (made, sold) as stand-alone filters for later inclusion in a cigarette, for example for use by smokers who assemble their own cigarettes (that is as a roll-your-own product).

The tobacco smoke filter or filter element according to any aspect of the invention may be of length 12 to 40 mm, e.g. 15 to 35 mm, e.g. 20 to 30 mm.

The tobacco smoke filter (or filter element) according to any aspect of the invention may be of circumference 14 to 28 mm, for example 16 to 26mm, for example 16 to 17 mm or 24 to 25 mm.

In a filter cigarette according to the invention, a filter of the invention (or a filter which includes a filter element of the invention) is joined to a wrapped tobacco rod with one end of the filter towards the tobacco. The filter may be joined to the wrapped tobacco rod by ring tipping [which engages around just the adjacent ends of the (wrapped) filter and rod to leave much of the filter wrap exposed], for example transparent ring tipping. The filter may be joined by a full tipping overwrap (which engages around the full filter length and the adjacent end of the tobacco rod). The full tipping overwrap may be transparent, e.g. along part of its length.

The filter, filter element or filter cigarette according to the invention may be ventilated by methods well known in the art, e.g. by use of a pre-perforated or air- permeable wrapper, and/or laser perforation of the wrapper and, if present, tipping overwrap. A ventilating full tipping overwrap may likewise be inherently air-permeable or provided with ventilation holes, and in ventilated products where both outer wrapper and tipping overwrap are present ventilation through the overwrap will usually (and preferably) be in register with that through the plug wrap. Ventilation holes through the filter outer wrapper, or through a tipping overwrap, or through both simultaneously, may be made by laser perforation during filter or filter cigarette production, as is well known in the art.

According to the invention in a further aspect there is provided a multiple rod comprising a plurality (e.g. 2, 4, 6 etc.) of filters (or filter elements) as described above and/or herein integrally joined end-to-end in a mirror image relationship.

According to the present invention in a further aspect, there is provided a method of making a tobacco smoke filter or filter element [e.g. a tobacco smoke filter or filter element comprising:

longitudinally extending (e.g. substantially cylindrical) core; and at least one continuous element which extends through the longitudinally extending (e.g. substantially cylindrical) core from one end of the core to the other end of the core, for example a tobacco smoke filter or filter element wherein the longitudinally extending (e.g. substantially cylindrical) core has a length I and the (or each) continuous element (which extends through the longitudinally extending core) has a length L, wherein L is greater (longer) than I]; the method comprising the steps of:

(a) continuously advancing, longitudinally, a train of tobacco smoke filtering material;

(b) inserting receptacles (e.g. capsules, e.g. frangible capsules) for additive, together with a separate continuous element (a continuous element which is separate from, e.g. not formed integrally with, the receptacles), into the advancing tobacco smoke filtering material, such that the receptacles are inserted at (e.g. predetermined, e.g. longitudinally- spaced) locations along the (e.g. advancing) train of tobacco smoke filtering material;

(c) gathering and securing the tobacco smoke filtering material around the receptacles and continuous element to form a continuous product rod comprising a longitudinally extending (e.g. substantially cylindrical) core of tobacco smoke filtering material engaged around the (e.g. longitudinally-spaced) receptacles and the continuous element; and (d) cutting the resulting continuous product rod.

The method may further comprise a step of shaping the continuous element into a bent, kinked or curved path which is maintained through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod. Shaping the continuous element into a bent, kinked or curved path may be prior to, or simultaneous with (e.g. the same step) or substantially simultaneous with the step of inserting the receptacles for additive, together with a separate continuous element, into the advancing tobacco smoke filtering material.

According to the present invention in a further aspect, there is provided an apparatus for making a tobacco smoke filter or filter element [e.g. a tobacco smoke filter or filter element comprising:

longitudinally extending (e.g. substantially cylindrical) core; and

at least one continuous element which extends through the longitudinally extending (e.g. substantially cylindrical) core from one end of the core to the other end of the core, for example a tobacco smoke filter or filter element wherein the longitudinally extending (e.g. substantially cylindrical) core has a length I and the (or each) continuous element (which extends through the longitudinally extending core) has a length L, wherein L is greater (longer) than I]; the apparatus comprising:

(a) advancing means for continuously advancing, longitudinally, a train of tobacco smoke filtering material;

(b) insertion means for inserting receptacles (e.g. capsules, e.g. frangible capsules) for additive, together with a separate continuous element (a continuous element which is separate from, e.g. not formed integrally with, the receptacles), into the advancing tobacco smoke filtering material, such that the receptacles are inserted at (e.g. predetermined, e.g. longitudinally-spaced) locations along the (e.g. advancing) train of tobacco smoke filtering material;

(c) gathering means for gathering and securing the tobacco smoke filtering material around the receptacles and continuous element to form a continuous product rod comprising a longitudinally extending (e.g. substantially cylindrical) core of tobacco smoke filtering material engaged around the (e.g. longitudinally-spaced) receptacles and the continuous element; and

(d) cutting means (e.g. a knife) for cutting the resulting continuous product rod. The apparatus may further comprise a continuous element shaper for shaping the continuous element into a bent, kinked or curved path which is maintained through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod. Shaping the continuous element into a bent, kinked or curved path may be prior to, or simultaneous with (e.g. the same step) or substantially simultaneous with the step of inserting the receptacles for additive, together with a separate continuous element, into the advancing tobacco smoke filtering material.

The receptacles (e.g. capsules, e.g. frangible capsules) for additive may be inserted into the advancing tobacco smoke filtering material simultaneously or substantially simultaneously with the separate continuous element.

The method may include a step of shaping (using a filtering material shaper) the continuously advancing tobacco smoke filtering material to a channel section [into which the receptacles and separate continuous element are inserted].

The receptacles and separate continuous element may be inserted by means of an applicator wheel or a drum having peripherally-spaced recesses around its applicator surface for receiving individual receptacles (capsules), the applicator wheel or drum being rotated into position so that the recesses insert their contents (the receptacles e.g.

capsules) into the tobacco smoke filtering material. The applicator wheel or drum preferably also includes applicator means (e.g. a slot or groove in the applicator surface) for receiving the continuous element, the applicator wheel or drum being rotated into position so that the applicator means inserts its contents (the continuous element) into the tobacco smoke filtering material (e.g. as the receptacles are being inserted into the tobacco smoke filtering material).

The recesses in the wheel or drum may be filled (with receptacles) continuously at or adjacent to the top of their travel path, and may discharge the receptacles at or adjacent to the bottom of their travel path. A means such as a guard shoe may be used for (a further method step of) preventing premature spillage of the receptacles from the recesses during travel from the filling region to the depositing region. The applicator means (e.g. a slot or groove in the applicator surface) in the wheel or drum preferably continuously receives the continuous element after the recesses in the wheel or drum have been filled (with receptacles), and discharges the continuous element as the receptacles are being inserted into the tobacco smoke filtering material. The guard shoe may prevent premature removal (slippage) of the continuous element from the applicator means during travel from the filling region to the depositing region. In this example, the applicator means may be located such that the continuous element covers the recesses in the wheel or drum (and the receptacles held therein) from when it is received into the applicator means until the continuous element is discharged (together with the receptacles) and inserted into the advancing tobacco smoke filtering material. In this example, the continuous element may serve as, or in addition to, the means for preventing premature spillage of the receptacles from the recesses.

In another, less preferred example, the applicator means (e.g. a slot or groove in the applicator surface) in the wheel or drum preferably continuously receives the continuous element before the recesses in the wheel or drum have been filled (with receptacles), and discharges the continuous element (i.e. inserts the continuous element into the tobacco smoke filtering material) as the receptacles are being inserted into the tobacco smoke filtering material. In this example, the applicator means may be located such that the receptacles held in the recesses in the wheel or drum cover the continuous element in the applicator means (and hold it in place in the applicator means) until the continuous element is discharged (together with the receptacles) and inserted into the advancing tobacco smoke filtering material.

The method may include a further step of controlling (e.g. by first control means) the position of the continuous element (e.g. thread) on the (e.g. outside of the) wheel or drum (e.g. controlling the position of the continuous element in the applicator), for example to ensure that the continuous element does not exert sufficient pressure on the receptacles (capsules) in the recesses to inadvertently rupture the receptacles (capsules). The method may include a further step of adjusting the position of the continuous element (e.g. thread) (e.g. for centrality) in the product rod (e.g. by the first control means, or different control means). A vision system may be used to measure the centrality of the continuous element (e.g. thread) where the product rods are subsequently cut. The vision system may be linked by a feedback mechanism to the aforementioned first or further control means to adjust the position of the thread.

Each receptacle (e.g. capsule) may be positively ejected from its recess in the wheel or drum and inserted onto/into the tow by operation of a plunger forming the base of the recess. Each recess may be provided with its own plunger, the plungers being operated sequentially to empty their recesses by engagement with a stationary cam surface (as they rotate past the cam).

It will be appreciated that there is interference between the position of the continuous element within the product rod (in the X-Y direction) and the position of the capsule in the product rod in the X-Y plane - i.e. because they are separate they both cannot occupy the same central space. For example, when there is a single continuous element, it is desirable that the continuous element is centrally located where the product rod is cut into multiple filter rods and subsequently into individual filters or elements (and the element becomes visible to the smoker), and that the capsule is centrally located in the middle of the product rod filter (where it can be ruptured by the application of an even pressure). There are various modifications by which this can be achieved. The plunger may be fitted with shaping means (e.g. a shaper) for pushing the continuous element along with the receptacle to thereby shape the continuous element into a bent, kinked or curved path (e.g. a wave or wavy path or pattern, e.g. a sinusoidal wave path or pattern), a path which is maintained through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod. In an alternative example, the outer surface of the wheel or drum (or the applicator means) may be undulating to thereby shape the continuous element into a bent, kinked or curved path (e.g. a wave or wavy path or pattern, e.g. a sinusoidal wave path or pattern), a path which is maintained through the

longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod.

Accordingly, the method may include a further step of shaping the continuous element into a bent, kinked or curved path (e.g. a wave or wavy path or pattern, e.g. a sinusoidal wave path or pattern), a path which is maintained through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod.

The recesses in the wheel or drum may be substantially circular or square in cross section, e.g. to provide an appropriate match to the shape and dimensions of the receptacles (e.g. capsules) being transported on the wheel or drum.

The present invention will now be illustrated with reference to the following

Examples and the attached drawings in which FIGURE 1 illustrates a view, part cut away, of a filter according to an example of the invention (not to scale); FIGURE 2 illustrates a cross section of the filter of Figure 1 (not to scale); FIGURE 3 is a diagrammatic elevation view of a complete apparatus for forming a tobacco smoke filter rod according to an aspect of the invention; FIGURE 4 is a side elevation, in section, of an applicator wheel and tow trumpet for use with the apparatus of Figure 3, for inserting capsules and a continuous element into the tobacco smoke filtering material when forming the tobacco smoke filter rod, FIGURE 4A being an enlarged view of part of Figure 4 showing capsules and continuous element as they are inserted into the rod, and FIGURE 4B showing an alternative pattern for inserting the capsules and continuous element into the rod; FIGURE 5 is a part-sectional view on the lines 5' of Fig. 4, and FIGURE 6 illustrates, in perspective, another example.

Figures 1 and 2 show an example of a tobacco smoke filter 1 according to an example of the invention. Tobacco smoke filter 1 includes a longitudinally extending, cylindrical, core 2 of length (I) 30mm and circumference around 25 mm. The core 2 comprises a filamentary tow of cellulose acetate tobacco smoke filtering material having 3 denier per filament and 35,000 total denier which has been plasticised with triacetin (at around 6- 8%w/w), as is well known in the art. The core 2 includes a receptacle for additive in the form of a spherical frangible capsule 3 of diameter 4 mm fully enclosed within the longitudinally extending, cylindrical, core 2. The frangible capsule 3 includes a frangible/breakable outer layer or shell 4 of gelatin which surrounds an additive, flavouring agent, in the form of a menthol solution 5. The menthol solution 5 is held within the outer layer/shell 4 within an enclosure defined by the inner surface of the outer layer/shell. This kind of capsule construction is well known in the art.

Filter 1 also includes a continuous element 7 in the form of a cotton thread of diameter 0.25 mm (and which is pigmented green, in contrast to the white cellulose acetate tow of core 2). The continuous element (thread) 7 extends through the longitudinally extending (e.g. substantially cylindrical) core 2 from one end of the core to the other end of the core. The continuous element (thread) 7 is fully enclosed within the longitudinally extending (e.g. substantially cylindrical) core, apart from at each end of the longitudinally extending core (where it is exposed). Thus, the (or each) continuous element is only visible at the ends of the longitudinally extending (e.g. substantially cylindrical) core 2, where it is centrally located (i.e. located at the centre point of the circular ends of core 2). As can be best seen in Figure 2, the continuous element (thread) 7 extends from one end of the core to the other end of the core and does not have gaps or breaks (or joints) along its length.

The longitudinally extending (e.g. substantially cylindrical) core 2 has a length I of 30 mm and the (or each) continuous element (thread) 7 (which extends through the longitudinally extending core) has a length L of approximately 35 to 37 mm. Thus, length L is greater (longer) than length I, and continuous element (thread) 7 is therefore longer than the longitudinally extending core through which it extends, and does not extend in a straight line through the longitudinally extending core [from one end of the core to the other end (of the core)]. As best seen in Figure 2, continuous element 7 follows a "wave" or curved path through the longitudinally extending core [from one end of the core to the other end (of the core)] such that the continuous element extends or bends around the capsule 3 (and the length of continuous element 7 can be accommodated over the shorter length I of the core). Thus, the continuous element 7 is centrally located at both ends of the core, and capsule 3 is centrally located within in the body of the filter, with the continuous element 7 following a curved path through the longitudinally extending core 2, bending around the capsule 3. This provides superior end appearance (for eye appeal or anticounterfeiting measures), because the visible ends of continuous element are centrally located (i.e. located at the centre point) of the circular ends of core 2 (as shown at one core end in Fig 1 ), while ensuring that the capsule 3 is centrally located within the filter 1 , which facilitates even capsule breakage and distribution of flavour when pressure is applied to the filter in use. The thread 7 may include additional menthol, or other, flavouring.

Figures 1 and 2 show an embodiment in which the continuous element 7 is not touching (not in direct contact with) capsule 3. It will be appreciated that in other

embodiments, the continuous element 7 may touch, or be in contact with, the capsule 3 within the core. However, even if the capsule 3 touches element 3, it will be appreciated that the continuous element 7 is not formed integrally with the capsule 3 (because they are separate entities). In other words, the capsule 3 is separate to (i.e. not formed as part of, not of unitary construction with) the continuous element 7.

The filter 1 includes a wrapper 8 of paper which is engaged around the core 2 and held in place by a lapped and stuck seam, as is well known in the art.

The filter 1 may be joined to a wrapped tobacco rod (not shown) with the upstream end of the core 2 towards the tobacco, to form a filter cigarette. The filter 1 may be joined to the wrapped tobacco rod by ring tipping [which engages around just the adjacent ends of the (wrapped) filter and rod to leave much of the wrapper 8 exposed], by methods which are well known in the art. In an alternative embodiment, the filter may be joined by a full tipping overwrap (which engages around the full filter length and the adjacent end of the tobacco rod).

The filter of Figures 1 and 2 may be made by an adaptation of conventional methods and apparatus for making capsule filters, for example using an adapted version of the method and apparatus described in GB1585761 , as described below with reference to Figures 3 to 6 (which employ like reference numerals from earlier Figures to indicate like items).

In the drawings, from a bale 101 of tobacco smoke filtering material in the form of cellulose acetate tow, the tow 102 is drawn through an air banding jet 104 over a cylindrical guide 105 by rollers 103. Rollers 106 rotate faster than rollers 103 to stretch the tow between themselves and rollers 103. A further air banding jet 107 forms the tow into a band approximately 250 mm wide before it passes into a box 110 where it is sprayed with glyceryl triacetate plasticiser by spray guns 108 and 109. The banding jets 104 and 107 are of known form and comprise a narrow slot through which the tow passes. On one side of the slot is a perforate wall communicating with a supply of compressed air and on the other side of the slot an imperforate wall retains the tow whilst the air impinges upon it. Rollers 11 hold the tow in the band form as it advances which form is continued until the tow passes through the tow trumpet 15 which (together with wire 12) converts the tow into a loosely condensed channel 55 of tobacco smoke filtering material (tow) having U-shaped cross section (see Fig 6) before it enters beneath a tongue 16. Thus, the rollers, together with the tow trumpet 15, serve to continuously advance, longitudinally, a train of tobacco smoke filtering material, to a point where receptacles (capsules) and a continuous member are inserted. Further, the tow trumpet serves to shape the continuously advancing tobacco smoke filtering material into a channel [into which the receptacles and separate continuous element are inserted, as described below].

Between trumpet 15 and tongue 16 is positioned an applicator wheel or drum 50 fed with capsules 3 from hopper 54, and a continuous element in the form of green cotton thread 7, fed from spool 7a. A flavouring agent (e.g. menthol) may be applied to the thread 7 by methods known in the art, for example by passing the thread through a menthol path positioned between the spool 7a and the drum 50. Alternatively or additionally, flavouring agent may be applied in liquid form directly to the tow (also by methods known in the art).

A suitable applicator wheel or drum, which can be employed as the wheel 50 in the embodiment of Fig 3, is illustrated in Figs. 4 and 5, and given reference number 70 in these figures (and Fig 6). The applicator wheel or drum 70 of Figs 4 and 5 is used for inserting receptacles (e.g. capsules 3) for additive, together with a separate continuous element in the form of green cotton thread 7, into the advancing tobacco smoke filtering material, such that the receptacles are inserted at (e.g. predetermined, e.g. longitudinally-spaced) locations along the (e.g. advancing) train of tobacco smoke filtering material. It should be noted that thread 7 is a continuous element which is separate from, e.g. not formed integrally with, the receptacles. Referring to Figs. 4 and 5, the applicator wheel 70 has radially extending cylindrical recesses 72 spaced equidistantly around its cylindrical surface. The base of each recess 72 is formed by the free end of a plunger or piston 74. Each piston 74 is resiliently biased by a spring 76 radially towards the centre 78 of the wheel, but is movable radially outwards against this spring bias to sweep through the recess and so positively eject its contents (positively eject capsule 3). Sequential operation of the pistons or plungers as the wheel rotates clockwise as seen in Fig. 4 is effected by means of stationary cam surface 80 which engages with the radially inner end of the pistons or plungers over a portion of their travel path as shown in Fig. 5.

In use in the method according to the invention, the applicator wheel 70 will be mounted as shown in and described with reference to Fig. 4, extending as shown down between the limbs of the channel 55 of loosely gathered tow advancing from trumpet 15 (see also Fig 6). As the wheel 70 rotates, each recess 72 is filled with an individual frangible capsule 3 from a hopper 71 as the recesses 72 pass around the top of their travel path. The pistons or plungers are operated by cam surface 80 to empty the capsules 3 from the recesses, into the U-shaped channel 55 of the continuously advancing train of tobacco smoke filtering material (see Fig 6), at the bottom of the travel path of the recesses, before the filtering material enters beneath the tongue 16.

The applicator wheel or drum also includes applicator means 207 in the form of a slot or groove in the applicator surface for receiving the continuous element (cotton thread) 7, the applicator wheel or drum 70 being rotated into position so that the applicator means inserts its contents (the continuous element 7) into the tobacco smoke filtering material (e.g. as the capsules 3 are being inserted into the tobacco smoke filtering material, before the filtering material enters beneath the tongue 16). As described above, the recesses in the wheel or drum are filled (with capsules 3) at or adjacent to the top of their travel path, and discharge the receptacles at or adjacent to the bottom of their travel path. A means such as a guard shoe may be used for preventing premature spillage of the receptacles from the recesses during travel from the filling region to the depositing region. The applicator means 207, a slot or groove in the wheel or drum, continuously receives the continuous element 7 from reel 7'after the recesses in the wheel or drum have been filled (with capsules 3), and discharges the continuous element 7 as the receptacles are being inserted into the tobacco smoke filtering material (see Fig 4). The guard shoe may prevent premature removal (slippage) of the continuous element from the applicator means during travel from the filling region to the depositing region. In the illustrated example, the applicator means 207 is located such that the continuous element 7 covers the recesses 72 in the wheel or drum (and the capsules 3 held therein) from the point when it is received into the applicator means 207 until the continuous element 7 is discharged (together with the receptacles) and inserted into the advancing tobacco smoke filtering material. The frangible capsules 3 are thus inserted into the advancing tobacco smoke filtering material simultaneously or substantially simultaneously with the separate continuous element 7. In this example, the continuous element 7 serves as, or in addition to, the means for preventing premature spillage of the capsules from the recesses.

In the illustrated example, the apparatus and method of the invention are being used to manufacture products which include capsules 3 and a single continuous element 7. [It will of course be appreciated that the apparatus of Figs 3 to 6 may be modified to produce other filters or filters of the invention, including more than one continuous element, more than one capsule etc.] Where a single continuous element is present in the product, it is generally desirable that the continuous element is centrally located (in the core of tobacco smoke filtering material) at positions where the product rod is cut into multiple filter rods and subsequently into individual filters or elements (and the element becomes visible to the smoker); and that the capsule is centrally located in the middle of the product rod filter (where it can be ruptured by the application of an even pressure). The

plungers/pistons 74 are fitted with shaping means for pushing the continuous element 7 along with the receptacle 3 to thereby shape the continuous element into a curved, e.g. substantially sinusoidal wave path or pattern, through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod. The curved pattern of the element 7 in the channel of tobacco smoke filtering material is best seen at the bottom of Fig 4, which is shown enlarged at Figure 4A. The shaping means has pushed the continuous element 7 along with the receptacles 3 into the U shaped channel 55 and shaped the continuous element 7 into a curve which undulates under the capsules within the channel 55 (lead line 55 in Figure 4A points to the bottom of the U, and it will be appreciated that the sides of the U are not shown because this is a cross section). The curve in the continuous element will be maintained in the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod, as the tobacco smoke filtering material is gathered around the capsules 3 and continuous element 7 to form a continuous product rod [comprising a longitudinally extending (e.g. substantially cylindrical) core of tobacco smoke filtering material engaged around the (e.g. longitudinally- spaced) capsules 3 and the continuous element 7].

In an alternative example, not shown, the outer surface of the wheel or drum (or the applicator means) may be undulating to thereby shape the continuous element into a bent, kinked or curved path (e.g. a wave or wavy path or pattern, e.g. a sinusoidal wave path or pattern) through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod.

The tongue 16 serves to guide the tow (into which the receptacles and continuous element have been inserted) into a heating enclosure 18 as well as correctly to position a pervious tape 19 around the tow. Heating enclosure 18, with tape 19, acts as a tubular former to condense and shape the tow to filter rod (product rod) form, as described below. The tobacco smoke filtering material is gathered around the capsules 3 and continuous element 7 to form a continuous product rod comprising a longitudinally extending (e.g. substantially cylindrical) core of tobacco smoke filtering material engaged around the (e.g. !ongitudinally-spaced) capsules 3 and the continuous element 7.

The pervious tape 19 which is drawn through the heating enclosure by drum 20 and which is further trained round rollers 21 , 22, 23 and 24 has an open structure and may be made from woven nylon polyethylene terephthalate monofilament. The tape may have a surface coating of silicone resin or polytetrafluoroethylene in order to prevent the tow 102 from adhering to it. The heating enclosure 18 is provided with a conduit 25 connected to a supply of steam which passes through passageways in the enclosure thence through the tape and into the tow in order to heat it and cause the glyceryl triacetate plasticiser to bond the filaments of cellulose acetate to each other.

Thus by the bonding of the filaments a continuous product rod 26 is formed. The longitudinal edges of the tape 19 do not generally meet each other perfectly so that some of the filaments of the tow press between the edges forming a ridge. This ridge is removed by a presser foot 27 which lies between the edges of the tape and serves to press upon the ridge thus reforming the product rod 26 into a substantially cylindrical shape. Then the product rod 26 passes into a cooling enclosure 28 wherein air or other gas supplied through conduit 30 passes through the tape and into contact with the filaments of the rod in order to cool them and to remove any condensate from the rod 26. Preferably, the cooling air passes through the tape at a multiplicity of points spaced along the length of the cooling enclosure 28. After passing through the rod, the air, with any entrained condensate, passes into receiver 17, which is vented towards the rear of the machine. The results of the action of the air is also to cause the rod to become more rigid.

Whilst the tape is passing about the drum 20 and the rollers 21 to 24 it occupies a flat form. During its passage from roller 24 to the drum 20 it is folded into an incomplete cylindrical form with a slight gap between its edges. On leaving the cooling enclosure 28 it opens out and is separated from the rod. The apertures in the tape are of sufficient size to provide an easy passage for the steam and the air to pass into the filaments and to effect heat transfer. The surface finish of the product rod 26 is dependent upon the surface characteristics of the tape since the filaments of the tow press against the tape whilst they are in a softened condition under the influence of the steam. If a deeply embossed finish to the rod is desired a coarse weave tape may be used. If a smoother rod is required a finely woven tape may be used. The embossing serves to inhibit fibre separation upon the peripheral surface of the rod without the need, in general of causing coalescence of the peripheral fibres of the rod.

If desired it may be arranged that the bore of the heating enclosure is slightly greater than the bore of the cooling enclosure. The latter then serves to set the rod in its final desired diameter.On leaving the cooling enclosure 28 the product rod 26 can pass directly to a cut off, but is preferably first wrapped (e.g. in a paper wrapper, by passage through a conventional wrapping device) and then passed to a cut off. In either case, the cut off sub-divides the (wrapped or unwrapped) rod into discrete lengths (product rods), the cuts being made between capsules 78. The rod may be cut into individual filters or filter elements, but is more usually cut into multiple rods each comprising a plurality (e.g. 2, 4, 6 etc.) of filters (or filter elements) as described above and/or herein joined end-to-end (e.g. in a mirror image relationship). Such multiple filter rods, and their subsequent incorporation into filter cigarettes, are well known in the art.

In an alternative method, the advancing tobacco smoke filtering material is gathered around the capsules 3 and continuous element 7 by a rod former (by conventional means) to form a continuous product rod comprising a longitudinally extending substantially cylindrical core of tobacco smoke filtering material engaged around the capsules 3 and continuous element 7. The continuous product rod is wrapped (by conventional means), and the wrapper secured in place using a lapped and stuck seam. This method of forming a rod, and using a lapped and stuck wrapper to hold the rod together, is well known in the art. The resulting continuous product rod is then cut by methods known in the art. The rod may be cut into individual filters or filter elements, but is more usually cut into multiple rods each comprising a plurality (e.g. 2, 4, 6 etc.) of filters (or filter elements) as described above and/or herein joined end-to-end (e.g. in a mirror image relationship). Such multiple filter rods, and their subsequent incorporation into filter cigarettes, are well known in the art.

A vision system can be used to measure the centrality of the continuous element (e.g. thread) 7 where the product rods are subsequently cut. The vision system may be linked by a feedback mechanism to a control means for adjustment of the position of the thread on the wheel 70 in the event this is not correct (e.g. not central).

The apparatus of Figs 3 to 6 includes control means for controlling the position of the continuous element 7 (e.g. thread) on the (e.g. outside of the) wheel or drum, for example to ensure that the continuous element does not exert sufficient pressure on the capsules 3 in the recesses 72 to inadvertently rupture the capsules 3. The control means may also be used to adjusting the position of the continuous element (e.g. thread) 7 (e.g. for centrality) in the product rod.

In another, less preferred example, the applicator means (e.g. a slot or groove in the applicator surface) in the wheel or drum preferably continuously receives the

continuous element before the recesses in the wheel or drum have been filled (with receptacles), and discharges the continuous element (i.e inserts the continuous element into the tobacco smoke filtering material) as the receptacles are being inserted into the tobacco smoke filtering material. In this example, the applicator means may be located such that the receptacles held in the recesses in the wheel or drum cover the continuous element in the applicator means (and hold it in place in the applicator means) until the continuous element is discharged (together with the receptacles) and inserted into the advancing tobacco smoke filtering material. The curved pattern of the element 7 in the channel of tobacco smoke filtering material in this less preferred element is shown in Figure 4B. The shaping means has pushed the continuous element 7 along with the receptacles 3 into the channel 55 and shaped the continuous element 7 into a curve which undulates over the capsules within the channel 55 (lead line 55 in Figure 4B points to the bottom of the U, and it will be appreciated that the sides of the U are not shown because this is a cross section). The curve in the continuous element will be maintained in the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod, as the tobacco smoke filtering material is gathered around the capsules 3 and continuous element 7 to form a continuous product rod [comprising a longitudinally extending (e.g. substantially cylindrical) core of tobacco smoke filtering material engaged around the (e.g. longitudinally-spaced) capsules 3 and the continuous element 7].

Figs. 4 and 5 also illustrate another feature, this being the use of a tow trumpet 15 which is provided with a channel section tow support 85 extending from its outlet to and past the region where the applicator wheel deposits the capsules 3 and the continuous element 7. This extension piece 85 supports the tow at the time of capsule and elongate member insertion and controls the tow correctly either side of the applicator wheel.

Fig. 6 illustrates, in perspective, parts of another example according to the invention. Fig. 6 employs like reference numerals from earlier Figures to indicate like items. In Fig. 6, the applicator wheel is of the same type as illustrated in Figs. 4 and 5, except that the tow trumpet 15 does not have the channel section extension running from its throat to the insertion location. The Figure 6 shows how the band of tow passing from the rolls 1 1 is deformed by former 12 into the shape of a shallow trough or channel for delivery to the tow trumpet 15, this ensuring a stable and symmetrical channel section of loosely gathered tow 55 for delivery to the applicator wheel 70.

Claims

1. A tobacco smoke filter or filter element comprising:

a longitudinally extending core of tobacco smoke filtering material;

at least one receptacle for an additive located in the longitudinally extending core; and

at least one continuous element which extends through the longitudinally extending core from one end of the core to the other end of the core,

wherein the longitudinally extending core has a length I and the (or each) continuous element has a length L, wherein L is greater (longer) than I.

2. A tobacco smoke filter or filter element comprising:

a longitudinally extending core of tobacco smoke filtering material;

two or more continuous elements which extend through the longitudinally extending core from one end of the core to the other end of the core.

3. A filter or filter element according to claim 2 wherein the longitudinally extending core has a length I and the (or each) continuous element has a length L, wherein length L is equal to or greater (longer) than length I.

4. A tobacco smoke filter or filter element comprising:

a longitudinally extending core of tobacco smoke filtering material;

wherein the continuous element(s) is not formed integrally with the receptacle(s).

5. A filter or filter element according to any preceding claim wherein the (or each) continuous element does not extend in a straight line through the longitudinally extending core from one end of the core to the other end of the core.

6. A filter or filter element according to any preceding claim wherein the (or each) continuous element follows a bent, kinked or curved path (through the longitudinally extending core from one end of the core to the other end of the core.

7. A filter or filter element according to any preceding claim wherein the (or each) continuous element follows a curved path through the longitudinally extending core such that the continuous element extends or bends around the (or each) receptacle.

8. A filter or filter element according to any preceding claim wherein the (or each) continuous element is centrally located at the ends of the core and the receptacle(s) is centrally located in the body of the core.

9. A filter or filter element according to any preceding claim wherein the continuous element(s) is not formed integrally with the receptacle(s).

10. A filter or filter element according to any preceding claim wherein the tobacco smoke filtering material comprises natural or synthetic filamentary tow, e.g. of cotton or plastics such as polyethylene or polypropylene, or cellulose acetate filamentary tow, natural or synthetic staple fibres, cotton wool, a web material such as paper (usually creped), an (e.g. synthetic) non-woven material, and/or an extruded material (e.g. starch, synthetic foams, extruded foams).

11. A filter or filter element according to any preceding claim wherein the (or each) receptacle is a capsule, for example a frangible capsule.

12. A filter or filter element according to any preceding claim wherein the additive in the receptacle is a flavouring agent.

13. A filter or filter element according to any preceding claim wherein the

(or each) continuous element is a thread or tape element or a continuous extruded element.

14. A filter or filter element according to any preceding claim wherein the (or each) continuous element is coloured or tinted.

15. A filter or filter element according to claim 14 wherein the (or each) continuous element is coloured or tinted in a colour which contrasts with the tobacco smoke filtering material.

16. A filter or filter element according to any preceding claim wherein the (or each) continuous element includes a flavouring agent.

17. A filter or filter element according to any preceding claim wherein the filter or filter element comprises a further additive (e.g. flavouring agent) located on and/or in the tobacco smoke filtering material.

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

19. A tobacco smoke filter or filter element substantially as hereinbefore described with reference to Figures 1 and 2 of the attached drawings.

20. A smoking article (e.g. a cigarette) comprising a tobacco smoke filter according to any preceding claim, or a tobacco smoke filter including a filter element according to any preceding claim, joined to a wrapped tobacco rod with one end of the filter towards the tobacco.

21. A multiple rod comprising a plurality (e.g. 2, 4, 6 etc.) of filters or filter elements according to any of claims 1 to 19 integrally joined end-to-end.

22. A method of making a tobacco smoke filter or filter element comprising the steps of:

(b) inserting receptacles for additive, together with a separate continuous element, into the advancing tobacco smoke filtering material, such that the receptacles are inserted at locations along the train of tobacco smoke filtering material;

(c) gathering and securing the tobacco smoke filtering material around the receptacles and continuous element to form a continuous product rod comprising a longitudinally extending core of tobacco smoke filtering material engaged around the receptacles and the continuous element; and

(d) cutting the resulting continuous product rod.

23. A method according to claim 22 comprising a further step of shaping the continuous element into a bent, kinked or curved path which is maintained through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod.

24. A method according to claim 22 or claim 23 which further comprises a step of shaping the continuously advancing tobacco smoke filtering material into a channel into which the receptacles and separate continuous element are inserted.

25. A method according to claim 22, 23 or 24 in which the receptacles and separate continuous element are inserted by means of an applicator wheel or a drum having peripherally-spaced recesses around its applicator surface for receiving individual receptacles, the applicator wheel or drum being rotated into position so that the recesses insert their contents into the tobacco smoke filtering material.

26. A method according to 25 in which the applicator wheel or drum includes applicator means for receiving the continuous element, the applicator wheel or drum being rotated into position so that the applicator means inserts its contents into the tobacco smoke filtering material.

27. A method according to any of claims 22 to 26 comprising a further step of controlling and/or adjusting the position of the continuous element.

28. A method according to any of claims 22 to 27 in which the receptacles are inserted into the advancing tobacco smoke filtering material simultaneously or substantially simultaneously with the separate continuous element.

29. An apparatus for making a tobacco smoke filter or filter element comprising:

(b) insertion means for inserting receptacles for additive, together with a separate continuous element, into the advancing tobacco smoke filtering material, such that the receptacles are inserted at locations along the train of tobacco smoke filtering material;

(c) gathering means for gathering and securing the tobacco smoke filtering material around the receptacles and continuous element to form a continuous product rod comprising a longitudinally extending core of tobacco smoke filtering material engaged around the receptacles and the continuous element; and

(d) cutting means for cutting the resulting continuous product rod.

30. Apparatus according to claim 29 further comprising a filtering material shaper for shaping the continuously advancing tobacco smoke filtering material into a channel into which the receptacles and separate continuous element are inserted.

31. Apparatus according to claim 29 or claim 30 further comprising an applicator wheel or a drum having peripherally-spaced recesses around its applicator surface for receiving individual receptacles, the applicator wheel or drum being rotated into position so that the recesses insert their contents into the tobacco smoke filtering material.

32. Apparatus according to claim 31 wherein the applicator wheel or drum includes applicator means for receiving the continuous element, the applicator wheel or drum being rotated into position so that the applicator means inserts its contents into the tobacco smoke filtering material.

33. Apparatus according to any of claims 31 or 32 further comprising a continuous element shaper for shaping the continuous element into a bent, kinked or curved path which is maintained through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod.

34. Apparatus according to any of claims 31 to 34 wherein each recess is provided with its own plunger, the plungers being operated sequentially to empty their recesses by engagement with a stationary cam surface as they rotate past the cam surface.

35. Apparatus according to claim 33 or claim 34 wherein each plunger is fitted with a continuous element shaper for pushing the continuous element along with the receptacle to thereby shape the continuous element into a bent, kinked or curved path which is maintained through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod.

36. Apparatus according to any of claims 31 to 33 wherein the outer surface of the wheel or drum is undulating to thereby shape the continuous element into a bent, kinked or curved path which is maintained through the longitudinally extending core of tobacco smoke filtering material in the subsequently formed product rod.

37. Apparatus substantially as hereinbefore described with reference to Figures 3 to 6 of the attached drawings.

38. A method substantially as hereinbefore described with reference to Figures 3 to 6 of the attached drawings.