FILTER ELEMENT, MOUTHPIECE AND COOLING ELEMENT

Abstract

There is disclosed a mouth piece, filter element or cooling element for an aerosol generating article comprising: a first section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the first section; a second section comprising a longitudinally extending core of filtering material; wherein the first section and the second section are adjacent and integral; wherein the channel has a non-circular transverse cross section which varies in the longitudinal direction by rotating about a longitudinal axis of the first section.

Description

The use of tube filter elements and tube mouth pieces in smoking articles is well known in the art. Typically, a tube filter element includes a cylindrical core of filtering material which includes a channel that extends longitudinally from an end of the cylindrical core. A tube filter element is usually included as part of a multi segment filter and the tube filter element is usually positioned at the mouth end of the smoking article to provide a distinctive end appearance. Existing tube filters therefore require a step of assembling the tube filter element with a further filter segment which requires complex assembly processes. When incorporated into a smoking article a tube filter may, during use, cause the smoke to leave the filter in a concentrated stream directed at the tongue of the user.

There is a need for a tube filter element which does not require assembly with a further filter segment and can be manufactured in a single continuous process. There is also a need for tube filters which have different sensory properties.

In recent years, non-combustible smoking products have become increasingly popular. Such products include heated tobacco products, also known as tobacco heating products or heat-not-burn products. Heated tobacco products generally include tobacco, a heating element and a power source. The heating element heats the tobacco to generate an aerosol which is delivered to the user via a mouthpiece. The mouthpiece may act to mimic the sensory aspects of a traditional smoking article filter. Additionally, some heat not burn products include a cooling element which cools the aerosol before it reaches the mouthpiece. Cooling elements are typically discrete elements that require assembly with other components that form the non-combustible smoking product.

In a first aspect of the present invention there is provided a mouth piece or filter element for an aerosol generating article comprising: a first section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the first section; a second section comprising a longitudinally extending core of filtering material wherein the first section and the second section are adjacent and integral; wherein the channel has a non-circular transverse cross section which varies in the longitudinal direction by rotating about a longitudinal axis of the first section.

The channel may have a transverse cross section which is a modified circle having one or more protuberant portions extending towards the centre of the circle, a cross shape, or a rectangle.

The channel is configured such that its transverse cross section at a first point along the length of the longitudinally extending core of filtering material may be rotated with respect to an adjacent point along the length of the longitudinally extending core of filtering material. It will be appreciated that the transverse cross section of the channel may rotate by more or less than 360 degrees along the length of the channel.

The applicant has found that during use, aerosol in the form of smoke which passes through the mouth piece or filter element is caused to take a non-linear, for example helical or spiral path, through the channel. It has been found that, in use, the mouth piece or filter element of the present invention leads to a different smoking sensation in which the smoke feels more dispersed within the mouth as compared to a standard tube filter element or mouthpiece. Without wishing to be bound by theory, it is thought that the non-linear, for example helical or spiral path taken by the smoke leads to these differences in sensory properties.

The applicant has found that having a second section that is adjacent and integral with the first section negates the need for the use of a further discrete filter segment in order to impart additional properties or functionality on the filter element. The mouthpiece or filter element of the present invention can be manufactured in a single continuous process meaning that assembly of multiple filter segments is not required. However, it will be appreciated that the mouthpiece or filter element of the invention is nevertheless compatible with being incorporated into a multi-segment filter if necessary.

The channel may be a tube or bore. Preferably the channel is surrounded by filtering material.

The non-circular transverse channel cross section may vary in the longitudinal direction by rotating about a longitudinal axis of the channel, for example the central longitudinal axis of the channel.

The second section may comprise a longitudinally extending core of continuous or homogenously dispersed filtering material. Preferably, the second section does not include a channel, such as a tube or a bore.

The first section may be at the mouth end of the filter element or mouthpiece, for example such that the channel is visible when the filter element or mouthpiece is in use.

The inner surface may comprise one or more ridge(s) which extend helically about a longitudinal axis of the first section, for example about the longitudinal axis of the channel, for example about the central longitudinal axis of the channel. The one or more ridges protrude from the inner surface. The one or more ridges may be formed in the inner surface. The one or more ridges may be integral with the inner surface.

In the case of the channel having a transverse cross section which is a modified circle having one or more protuberant portions extending from the edge of the circle towards the centre of the circle, then the channel has a substantially cylindrical shape in which the inner surface defining the channel comprises one or more ridges which extend helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

In the case of the channel having a transverse cross section which is a cross shape, the channel has a substantially cylindrical shape, in which the inner surface defining the channel comprises four ridges which extend helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

The mouth piece or filter element may comprise a first section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the second section; a second section comprising a longitudinally extending core of filtering material; wherein the inner surface comprises one or more ridge(s) which extend helically about a longitudinal axis of the first section; and wherein the first section and the second section are adjacent and integral.

The applicant has found that in use the presence of one or more ridge(s) extending helically about a longitudinal axis of the first section leads to a different and improved smoke mouth feel compared to a standard tube mouth piece or filter element which has a constant transverse cross section in the longitudinal direction.

The applicant has found that during use, aerosol in the form of smoke which passes through the mouth piece or filter element is caused to take a helical or spiral path through the channel. It has been found that, in use, the mouth piece or filter of the present invention leads to a different smoking sensation in which the smoke feels more dispersed within the mouth as compared to a standard tube filter element or mouthpiece. Without wishing to be bound by theory, it is thought that the helical path taken by the smoke leads to these differences in sensory properties.

The applicant has also found that the inclusion of one or more ridge(s) which extend helically about the longitudinal axis of the or each channel may lead to improved filtration as compared to a filter element which includes a channel having a uniform transverse cross section in the longitudinal direction. The one or more ridges may increase the surface area of the inner surface of the or each channel, which leads to an increased surface area for adsorption.

The applicant has found that having a second section that is adjacent and integral with the first section negates the need for the use of a further discrete filter segment in order to impart additional properties or functionality on the filter element. The mouthpiece or filter element of the present invention can be manufactured in a single continuous process meaning that assembly of multiple filter segments is not required. However, it will be appreciated that the mouthpiece or filter element of the invention is nevertheless compatible with being incorporated into a multi-segment filter.

The channel may be a tube or bore. Preferably the channel is surrounded by filtering material.

The non-circular transverse channel cross section may vary in the longitudinal direction by rotating about a longitudinal axis of the channel, for example the central longitudinal axis of the channel.

The channel may extend along the entire length of the first section.

Preferably, each longitudinally extending core of filtering material is substantially cylindrical, for example cylindrical. The longitudinally extending core of filtering material may have a circumference from 14 mm to 25 mm.

The first section may have a wall thickness which is not constant because of the presence of the one or more ridges on the inner surface of the core. The wall thickness at the narrowest point may be from 0.6 mm to 2.3 mm, for example 1.8 to 2.3 mm. The wall thickness is defined herein as the distance between the outer surface and the inner surface of the longitudinally extending core.

The channel may be substantially cylindrical. It will be appreciated that while the channel may be substantially cylindrical, the transverse cross section will not be circular, for example the transverse cross section may be cross shaped, rectangular or a modified circle which includes one or more protuberant portions extending from the edge of the circle towards the centre of the circle.

Preferably the channel extends from the mouth end of the core of filtering material.

The channel may have a diameter at its widest point of from 1.5 mm to, 6 mm for example 1.5 mm to 5 mm.

The channel may have a diameter at its widest point of from 2 mm to 6 mm, for example 3 mm to 5 mm, for example 3.4 mm to 4.8 mm, for example from 3.5 mm to 4.7 mm, for example 3.7 mm or 4.5 mm.

The one or more ridges may extend along part of the length of the inner surface of the core. Preferably, the ridges extend along the full length of the inner surface of the core. The ridges may have a width of 1.0 mm to 2 mm, for example 1.2 to 1.7 mm, for example 1.5 mm. The ridges may have a height of from 0.2 to 1.5 mm.

The inner surface of the core may comprise one, two, three or four ridges extending helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel. The inner surface of the core may comprise two or more ridges extending helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel. Preferably, the inner surface of the core comprises two ridges extending helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

The first section may comprise more than one channel, for example two, three or four channels extending longitudinally from an end of the core.

The outer circumference of the mouthpiece or filter element may be between 14 and 25 mm.

The length of the mouthpiece or filter element may be between 4.0 mm and 50 mm, for example between 5 mm and 32 mm.

The second section may comprise a longitudinally extending core of continuous or homogenously dispersed filtering material. Preferably, the second section does not include a channel, such as a tube or a bore.

The mouth piece or filter element may comprise a third section comprising a longitudinally extending core of filtering material; wherein the third section is adjacent to the first section and integral with the first section, such that the first section is between the third section and the second section.

Alternatively, the mouth piece or filter element may comprise a third section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the third section.

The third section channel may have a non-circular transverse cross section which varies in the longitudinal direction by rotating about a longitudinal axis of the third section.

The third section channel may have a transverse cross section which is a modified circle having one or more protuberant portions extending towards the centre of the circle, a cross shape, or a rectangle. The third section may be adjacent to the second section and integral with the second section, such that the second section is between the first section and the third section.

The inner surface of the third section channel may comprise one or more ridge(s) which extend helically about a longitudinal axis of the third section.

The third section may be adjacent to the second section and integral with the second section, such that the second section is between the first section and the third section.

Preferably, the third section channel extends from the free end of the third section. The third section may be substantially the same as the first section. The third section channel is configured such that its transverse cross section at a first point along the length of the longitudinally extending core of filtering material may be rotated with respect to an adjacent point along the length of the longitudinally extending core of filtering material. It will be appreciated that the transverse cross section of the channel may rotate by more or less than 360 degrees along the length of the channel.

The third section channel may be a tube or bore. Preferably the third section channel is surrounded by filtering material.

The non-circular transverse channel cross section may vary in the longitudinal direction by rotating about a longitudinal axis of the channel, for example the central longitudinal axis of the channel.

The third section inner surface may comprise one or more ridge(s) which extend helically about a longitudinal axis of the third section, for example about the longitudinal axis of the channel, for example about the central longitudinal axis of the channel. The one or more ridges protrude from the inner surface. The one or more ridges may be formed in the inner surface. The one or more ridges may be integral with the inner surface.

In the case of the third section channel having a transverse cross section which is a modified circle having one or more protuberant portions extending from the edge of the circle towards the centre of the circle, then the channel has a substantially cylindrical shape in which the inner surface defining the channel comprises one or more ridges which extend helically about a longitudinal axis of the third section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

In the case of the third section channel having a transverse cross section which is a cross shape, the channel has a substantially cylindrical shape, in which the inner surface defining the channel comprises four ridges which extend helically about a longitudinal axis of the third section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

The third section channel may extend along the entire length of the third section.

Preferably, each longitudinally extending core of filtering material is substantially cylindrical, for example cylindrical. The longitudinally extending core of filtering material may have a circumference from 14 mm to 25 mm.

The third section may have a wall thickness which is not constant because of the presence of the one or more ridges on the inner surface of the core. The wall thickness at the narrowest point may be from 0.6 mm to 2.3 mm, for example 1.8 to 2.3 mm. The wall thickness is defined herein as the distance between the outer surface and the inner surface of the longitudinally extending core.

The third section channel may be substantially cylindrical. It will be appreciated that while the channel may be substantially cylindrical, the transverse cross section will not be circular, for example the transverse cross section may be cross shaped, rectangular or a modified circle which includes one or more protuberant portions extending from the edge of the circle towards the centre of the circle.

The third section channel may have a diameter at its widest point of from 1.5 mm to, 6 mm for example 1.5 mm to 5 mm.

The third section channel may have a diameter at its widest point of from 2 mm to 6 mm, for example 3 mm to 5 mm, for example 3.4 mm to 4.8 mm, for example from 3.5 mm to 4.7 mm, for example 3.7 mm or 4.5 mm.

The one or more ridges may extend along part of the length of the inner surface of the core.

Preferably, the ridges extend along the full length of the inner surface. The ridges may have a width of 1.0 mm to 2 mm, for example 1.2 to 1.7 mm, for example 1.5 mm. The ridges may have a height of from 0.2 to 1.5 mm.

The inner surface of the third section core may comprise one, two, three or four ridges extending helically about a longitudinal axis of the third section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel. The inner surface of the core may comprise two or more ridges extending helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel. Preferably, the inner surface of the third section core comprises two ridges extending helically about a longitudinal axis of the third section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

In the case of the filter element or mouth piece having a first section and a second section only, the first section may have a length of from 5 mm to 10 mm, for example 7 mm. The second section may have a length from 15 to 35 mm, for example 10 mm. In the case of the filter element or mouth piece having a first section a second section and a third section, the length of the first, second and third sections may each independently be from 5 to 15 mm, for example 11 mm.

Preferably, the first section, second section and third section, if present, comprise the same type of filtering material.

The filtering material may be a material conventionally employed for tobacco smoke filter manufacture, for example a filamentary material, fibrous material, web material or extruded material. The filtering material may be natural or synthetic filamentary tow, for example cotton or polymers such as polyethylene, polypropylene or cellulose acetate tow.

The filtering material may be a thermoplastic or otherwise spinnable polymer, for example polypropylene, polyethylene terephthalate or polyactide. It may be, for example, natural or synthetic staple fibres, cotton wool, web material such as paper (usually creped) and synthetic non-wovens, and extruded material (e.g. starch, synthetic foams). Preferably, the filtering material is a material which can be hardened using a plasticiser. Preferably the filtering material comprises cellulose acetate filamentary tow.

The total denier of the filtering material may be from around 20,000 to 100,000 g per 9000 m, for example 20,000 to 80,000 g per 9000 m, for example 20,000 to 50,000 g per 9000 m.

In the case of the filtering material being formed from a single bale of tow, the total denier of the filtering material may be from around 20,000 to 50,000 g per 9000 m for example from 30,000 g to 40,000 g per 9000 m, for example from 30,000 g to 38,000 g per 9000 m, for example 30,000 g, 32,000 g, 33,000 g, 37,000 g or 40,000 g per 9000 m.

In the case of the filtering material being formed from two bales of tow, the total denier of the filtering material may be from around 40,000 to 100,000 g per 9000 m for example from 60,000 g to 80,000 g per 9000 m, for example from 60,000 g to 76,000 g per 9000 m, for example 60,000 g, 64,000 g, 66,000 g, 74,000 g or 80,000 g per 9000 m.

The filament denier may be from 5 g to 9 g per 9000 m, for example 5 g, 7.3 g, 8 g or 9.0 g per 9000 m.

Filtering material is typically described by reference to the filament denier, the total denier and the fibre cross section. For example, the filtering material may comprise tow having the following denier: 8.0Y40, 8.0Y32, 7.3Y33, or 9.0Y37. For example, filtering material having a denier of 8.0Y40 means that the filament denier is 8.0 g per 9000 m, the total denier is 40000 g per 9000 m and the filaments have a Y shaped cross section.

The filtering material may comprise a plasticiser. The filtering material may include a plasticiser in an amount of from about 12% to 24% by weight of the filtering material and plasticiser, for example about 14% to 22%, for example about 16% to 20%, for example about 17 to 19%, for example about 18% of the weight of the filtering material and plasticiser.

The amount of plasticiser present in the mouthpiece or filter element is calculated as a percentage of the total weight of the filtering material and plasticiser via the general equation presented below.

$\mathrm{Percentage}\mathrm{of}\mathrm{plasticiser}\%=\frac{\mathrm{amount}\mathrm{of}\mathrm{plasticiser}\left(g\right)}{\mathrm{amount}\mathrm{of}\mathrm{plasticiser}\left(g\right)+\mathrm{amount}\mathrm{of}\mathrm{filtering}\mathrm{material}\left(g\right)}\times 100$

In the case of fibrous filtering material such as filamentary tow, the plasticiser acts to harden the fibres of the filtering material. Hardening the fibres of the filtering material may improve the shape definition of the filter element, and in particular the definition of the channel. For example, the filtering material may comprise plasticised fibres, for example plasticised tow, for example plasticised cellulose acetate tow. The formation of plasticised tow is well known in the art. The plasticiser may be, for example, triacetin, triethyleneglycol diacetate (TEGDA) or polyethylene glycol (PEG). The plasticiser may be applied to the filtering material by spraying onto the surface of the filtering material using methods known in the art.

The filtering material may optionally include a binder material. The filtering material may optionally include a water soluble binder material. Examples of water soluble materials include water soluble polymer materials such as polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl ether, starches, polyethylene glycols and polypropylene glycols; blends of water soluble binders with plasticisers such as triacetin, triethyleneglycol diacetate (TEGDA), or polyethylene glycol (PEG); and hot melt water soluble binders in particulate form. The inclusion of a water soluble binder material may further enhance the ability of the filter to be readily and swiftly degraded e.g. under environmental conditions.

The filtering material may include an additive. The additive may be a particulate additive. The particulate additive may be any particulate additive suitable for use in a smoke filter—e.g. activated carbon, zeolite, ion exchange resin (e.g. a weakly basic anion exchange resin), sepiolite, silica gel, alumina, molecular sieves, carbonaceous polymer resins and diatomaceous earths. The particulate additive may be a mixture of two, or more, materials. The additive may be a pigment, for example a pearlescent pigment or a thermo-chromatic pigment.

The additive may include a smoke modifying agent (for example a flavourant). The flavourant may, for example, be menthol, spearmint, peppermint, nutmeg, cinnamon, clove, lemon, chocolate, peach, strawberry, vanilla etc. The smoke modifying agent (e.g. flavourant) may be applied to the filtering material in liquid form. The smoke modifying agent (e.g. flavourant) may be liquefied prior to application to the filtering material, for example by heating above the melting point, for example by mixing with a liquid carrier. The smoke modifying agent (e.g. flavourant) may be mixed with and applied with a plasticiser, for example by spraying the mixture of smoke modifying agent (e.g. flavourant) and plasticiser onto the filtering material. A preferred smoke modifying agent (e.g. flavourant) is menthol or clove.

The mouth piece or filter element may be for use as part of a tobacco smoke filter or filter for a non-tobacco smokable material, for example marijuana. The mouth piece or filter element may be for use as part of a con-combustible tobacco product, such as a tobacco heating product device.

The mouth piece or filter element of the present invention may be incorporated into a smoking article, such as a cigarette, cigarillo, cigar and the like. The mouthpiece or filter element of the present invention may be incorporated into a tobacco heating product or an e-cigarette. The mouth piece or filter element may also be used alone or as part of a filter which is assembled by a user to form a smoking article, for example a roll-your-own smoking article.

The mouthpiece or filter element of the present invention may be incorporated into a multi-segment filter as a single segment. For example, a mouthpiece or filter element of according to any statement set out above may be joined with a further filter element containing an additive e.g. granular additive e.g. activated carbon granules. The mouthpiece or filter element of the present invention may be joined with a filter element containing a capsule e.g. a frangible capsule, e.g. a capsule containing a flavourant. The mouthpiece or filter element of the present invention may be joined with a filter element containing a flavourant e.g. (menthol) or multiple flavourants.

In a further aspect of the present invention, there is provided a filter for an aerosol generating article, for example a tobacco smoke filter, comprising a filter element according to any statement set out above. The filter, for example a tobacco smoke filter, may further comprise one or more further filter element(s). Such a filter which comprises more than one filter element may be referred to as a multi segment filter.

The one or more further filter elements may comprise a longitudinally extending core of filtering material as defined above. The one or more further filter elements may comprise an additive.

The one or more further filtering element may include fully enclosed (e.g. embedded) pocket(s) of additive embedded therein. The additive may be a particulate additive such as activated carbon (see above), which is for example enclosed within the filtering material as a discrete pocket or pod of particles of particulate additive which is substantially separate from, and fully enclosed within, the filtering material. In another example, the fully enclosed (e.g. embedded) pocket(s) of additive may be a frangible capsule or capsules, or one or a plurality of frangible microcapsules. The capsule(s) or microcapsule(s) may contain a variety of media—e.g. a smoke modifying agent such as a flavourant (such as those flavourants disclosed above) and/or a liquid, solid or other material e.g. to aid smoke filtration.

The one or more further filter elements may include a flavourant provided in and/or on a thread. “Flavour Thread” filter elements are well known in the art. Such filter elements incorporate a thread or tape element, typically longitudinally aligned therein, the element carrying a smoke modifying agent such as a flavourant.

The filter may comprise an outer wrapper, for example plugwrap, which surrounds the filter element or one or more filter elements. The wrapper may be paper, for example an air permeable paper. The wrapper may have a weight from 20 to 50 grams per square metre, for example from 27 to 35 grams per square metre. Particulate additives such as those discussed above may be applied to the wrapper or plugwrap surrounding the filter material, for example as described in GB 2261152. The further filter element may be wrapped by an outer wrapper, for example a plugwrap, which surrounds the further filter element. The filter element as defined according to any statement set out above and the further filter element may together be wrapped by an outer wrapper, such as a plug wrap. The outer wrapper may function to join the filter elements and secure them in place.

In a further aspect of the present invention there is provided an aerosol generating article comprising a filter, filter element or mouthpiece as described above. The aerosol-generating article may be a smoking article. The smoking article may include a filter as set out above that is joined to a wrapped rod of smoking material such as tobacco smoking material. Generally, in the case of a smoking article comprising marijuana smoking material, the smoking article includes a mouth piece according to any statement set out above. The smoking article may further comprise a tipping wrapper, for example a tipping paper. The tipping wrapper joins the wrapped rod of smoking material to the filter or mouthpiece by engaging around the adjacent ends of the filter or mouthpiece and the wrapped rod of smoking material. The tipping wrapper may be configured to leave some of the outer surface of the filter/mouthpiece or filter wrapper exposed. The filter may be joined to the wrapped rod of smoking material by a full tipping wrapper which engages around the full filter or mouthpiece length and the adjacent end of the rod of smoking material.

The mouthpiece, filter element, filter or smoking article according to the invention may be unventilated, or may be ventilated by methods well known in the art, e.g. by use of a pre-perforated or air-permeable filter wrapper (plugwrap) or tipping wrapper (tipping paper), and/or laser perforation of the filter wrapper and/or tipping wrapper. The mouthpiece, filter, filter element or smoking article according to the invention may be ventilated by laser perforation of the longitudinally extending core of filtering material (as well as wrapper(s) (plugwrap) and tipping wrapper (tipping paper) if present). A ventilating full tipping wrapper (tipping paper) may likewise be inherently air-permeable or may be provided with ventilation holes, and for ventilated products where both filter wrapper (plugwrap) and tipping wrapper (tipping paper) are present, ventilation through the tipping wrapper (tipping paper) will usually be in register with that through the filter wrapper (plug wrap). Ventilation holes through a filter wrapper (plugwrap), or through a tipping wrapper (tipping paper), or through both simultaneously, may be made by laser perforation during mouthpiece, filter or filter element production.

In a further aspect of the present invention there is provided a multiple rod comprising a plurality of mouthpieces or filter elements according to the invention arranged end-to-end in a mirror image relationship.

The aerosol-generating article may be a heated aerosol generating system.

The heated aerosol generating system may include a rod of tobacco material, a heating element, a power source, one or more cooling elements and a mouthpiece or filter element according to any statement set out above. The one or more cooling elements may be positioned downstream from the heating element and tobacco rod. In use, the tobacco rod is heated to thereby generate a heated aerosol. The heated aerosol then passes through the one or more cooling elements which act to cool the aerosol before it passes through the mouthpiece and into the user's mouth.

Herein, an aerosol generating article may include a smoking article such as a cigarette, cigar, cigarillo, roll your own cigarette and the like; heated tobacco products such as heat not burn devices, tobacco heating devices and the like; and electronic cigarettes.

In a further aspect of the present invention there is provided a cooling element for an aerosol generating article comprising: a first section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the first section; a second section comprising a longitudinally extending core of filtering material wherein the first section and the second section are adjacent and integral; wherein the channel has a non-circular transverse cross section which varies in the longitudinal direction by rotating about a longitudinal axis of the first section.

The channel may have a transverse cross section which is a modified circle having one or more protuberant portions extending towards the centre of the circle, a cross shape, or a rectangle.

The channel is configured such that its transverse cross section at a first point along the length of the longitudinally extending core of filtering material may be rotated with respect to an adjacent point along the length of the longitudinally extending core of filtering material. It will be appreciated that the transverse cross section of the channel may rotate by more or less than 360 degrees along the length of the channel.

The applicant has found that during use, heated aerosol which passes through the cooling element is caused to take a helical or spiral path through the or each channel. Without wishing to be bound by theory, it is thought that the helical path taken by the heated aerosol cools the aerosol.

The channel may be a tube or bore. Preferably the channel is surrounded by filtering material.

The non-circular transverse channel cross section may vary in the longitudinal direction by rotating about a longitudinal axis of the channel, for example the central longitudinal axis of the channel.

The second section may comprise a longitudinally extending core of continuous or homogenously dispersed filtering material. Preferably, the second section does not include a channel, such as a tube or a bore.

The inner surface may comprise one or more ridge(s) which extend helically about a longitudinal axis of the first section, for example about the longitudinal axis of the channel, for example about the central longitudinal axis of the channel. The one or more ridges protrude from the inner surface. The one or more ridges may be formed in the inner surface. The one or more ridges may be integral with the inner surface.

In the case of the channel having a transverse cross section which is a modified circle having one or more protuberant portions extending from the edge of the circle towards the centre of the circle, then the channel has a substantially cylindrical shape in which the inner surface defining the channel comprises one or more ridges which extend helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

In the case of the channel having a transverse cross section which is a cross shape, the channel has a substantially cylindrical shape, in which the inner surface defining the channel comprises four ridges which extend helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

The cooling element may comprise a first section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the second section; a second section comprising a longitudinally extending core of filtering material; wherein the inner surface comprises one or more ridge(s) which extend helically about a longitudinal axis of the first section; and wherein the first section and the second section are adjacent and integral.

The channel may be a tube or bore. Preferably the channel is surrounded by filtering material.

The non-circular transverse channel cross section may vary in the longitudinal direction by rotating about a longitudinal axis of the channel, for example the central longitudinal axis of the channel.

The channel may extend along the entire length of the first section.

Preferably, each longitudinally extending core of filtering material is substantially cylindrical, for example cylindrical. The longitudinally extending core of filtering material may have a circumference from 14 mm to 25 mm.

The first section may have a wall thickness which is not constant because of the presence of the one or more ridges on the inner surface of the core. The wall thickness at the narrowest point may be from 0.6 mm to 2.3 mm, for example 1.8 to 2.3 mm. The wall thickness is defined herein as the distance between the outer surface and the inner surface of the longitudinally extending core.

The channel may be substantially cylindrical. It will be appreciated that while the channel may be substantially cylindrical, the transverse cross section will not be circular, for example the transverse cross section may be cross shaped, rectangular or a modified circle which includes one or more protuberant portions extending from the edge of the circle towards the centre of the circle

The channel may have a diameter at its widest point of from 1.5 mm to, 6 mm for example 1.5 mm to 5 mm.

The channel may have a diameter at its widest point of from 2 mm to 6 mm, for example 3 mm to 5 mm, for example 3.4 mm to 4.8 mm, for example from 3.5 mm to 4.7 mm, for example 3.7 mm or 4.5 mm.

The one or more ridges may extend along part of the length of the inner surface of the core. Preferably, the one or more ridges extend along the full length of the inner surface of the core. The ridges may have a width of 1.0 mm to 2 mm, for example 1.2 to 1.7 mm, for example 1.5 mm. The ridges may have a height of from 0.2 to 1.5 mm.

The inner surface of the core may comprise one, two, three or four ridges extending helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel. The inner surface of the core may comprise two or more ridges extending helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel. Preferably, the inner surface of the core comprises two ridges extending helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

The cooling element may comprise more than one channel, for example two, three or four channels extending longitudinally from an end of the core.

The outer circumference of the cooling element may be between 14 and 25 mm.

The length of cooling element may be between 4.0 mm and 50 mm, for example between 5 mm and 32 mm.

The second section may comprise a longitudinally extending core of continuous or homogenously dispersed filtering material. Preferably, the second section does not include a channel, such as a tube or a bore.

The cooling element may comprise a third section comprising a longitudinally extending core of filtering material; wherein the third section is adjacent to the first section and integral with the first section, such that the first section is between the third section and the second section.

Alternatively, the mouth piece or filter element may comprise a third section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the third section.

The third section channel may have a non-circular transverse cross section which varies in the longitudinal direction by rotating about a longitudinal axis of the third section. The channel may have a transverse cross section which is a modified circle having one or more protuberant portions extending towards the centre of the circle, a cross shape, or a rectangle. The third section may be adjacent to the second section and integral with the second section, such that the second section is between the first section and the third section.

The inner surface of the third section channel may comprise one or more ridge(s) which extend helically about a longitudinal axis of the third section.

The third section may be adjacent to the second section and integral with the second section, such that the second section is between the first section and the third section.

Preferably, the channel extends from the free end of the third section. The third section may be substantially the same as the first section. The third section channel is configured such that its transverse cross section at a first point along the length of the longitudinally extending core of filtering material may be rotated with respect to an adjacent point along the length of the longitudinally extending core of filtering material. It will be appreciated that the transverse cross section of the channel may rotate by more or less than 360 degrees along the length of the channel.

The third section channel may be a tube or bore. Preferably the third section channel is surrounded by filtering material.

The non-circular transverse channel cross section may vary in the longitudinal direction by rotating about a longitudinal axis of the channel, for example the central longitudinal axis of the channel.

The third section inner surface may comprise one or more ridge(s) which extend helically about a longitudinal axis of the third section, for example about the longitudinal axis of the channel, for example about the central longitudinal axis of the channel. The one or more ridges protrude from the inner surface. The one or more ridges may be formed in the inner surface. The one or more ridges may be integral with the inner surface.

In the case of the third section channel having a transverse cross section which is a modified circle having one or more protuberant portions extending from the edge of the circle towards the centre of the circle, then the channel has a substantially cylindrical shape in which the inner surface defining the channel comprises one or more ridges which extend helically about a longitudinal axis of the third section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

In the case of the third section channel having a transverse cross section which is a cross shape, the channel has a substantially cylindrical shape, in which the inner surface defining the channel comprises four ridges which extend helically about a longitudinal axis of the third section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

The third section channel may extend along the entire length of the third section.

Preferably, each longitudinally extending core of filtering material is substantially cylindrical, for example cylindrical. The longitudinally extending core of filtering material may have a circumference from 14 mm to 25 mm.

The third section may have a wall thickness which is not constant because of the presence of the one or more ridges on the inner surface of the core. The wall thickness at the narrowest point may be from 0.6 mm to 2.3 mm, for example 1.8 to 2.3 mm. The wall thickness is defined herein as the distance between the outer surface and the inner surface of the longitudinally extending core.

The third section channel may be substantially cylindrical. It will be appreciated that while the channel may be substantially cylindrical, the transverse cross section will not be circular, for example the transverse cross section may be cross shaped, rectangular or a modified circle which includes one or more protuberant portions extending from the edge of the circle towards the centre of the circle.

The third section channel may have a diameter at its widest point of from 1.5 mm to, 6 mm for example 1.5 mm to 5 mm.

The third section channel may have a diameter at its widest point of from 2 mm to 6 mm, for example 3 mm to 5 mm, for example 3.4 mm to 4.8 mm, for example from 3.5 mm to 4.7 mm, for example 3.7 mm or 4.5 mm.

The one or more ridges may extend along part of the length of the inner surface of the core.

Preferably, the ridges extend along the full length of the inner surface. The ridges may have a width of 1.0 mm to 2 mm, for example 1.2 to 1.7 mm, for example 1.5 mm. The ridges may have a height of from 0.2 to 1.5 mm.

The inner surface of the third section core may comprise one, two, three or four ridges extending helically about a longitudinal axis of the third section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel. The inner surface of the core may comprise two or more ridges extending helically about a longitudinal axis of the first section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel. Preferably, the inner surface of the third section core comprises two ridges extending helically about a longitudinal axis of the third section, for example about a longitudinal axis of the channel, for example about the central longitudinal axis of the channel.

The channel in the first section or the third section may comprise, for example house, a heating element.

The applicant has found that a cooling element which includes a first section, second section and third section as described herein can house a heating element within the channel in either the first section or the third section. In such a case, the second section and the remaining section may act to cool the aerosol formed by the heating element.

In the case of the cooling element having a first section and a second section only, the first section may have a length of from 5 mm to 10 mm, for example 7 mm. The second section may have a length from 15 to 35 mm, for example 10 mm. In the case of the filter element or mouth piece having a first section a second section and a third section, the length of the first, second and third sections may each independently be from 5 to 15 mm, for example 11 mm.

Preferably, the first section, second section and third section if present comprise the same type of filtering material.

The filtering material may be a material conventionally employed for tobacco smoke filter manufacture, for example a filamentary material, fibrous material, web material or extruded material. The filtering material may be natural or synthetic filamentary tow, for example cotton or polymers such as polyethylene, polypropylene or cellulose acetate tow.

The filtering material may be a thermoplastic or otherwise spinnable polymer, for example polypropylene, polyethylene terephthalate or polyactide. It may be, for example, natural or synthetic staple fibres, cotton wool, web material such as paper (usually creped) and synthetic non-wovens, and extruded material (e.g. starch, synthetic foams). Preferably, the filtering material is a material which can be hardened using a plasticiser. Preferably the filtering material comprises cellulose acetate filamentary tow.

The total denier of the filtering material may be from around 20,000 to 100,000 g per 9000 m, for example 20,000 to 80,000 g per 9000 m, for example 20,000 to 50,000 g per 9000 m.

In the case of the filtering material being formed from a single bale of tow, the total denier of the filtering material may be from around 20,000 to 50,000 g per 9000 m for example from 30,000 g to 40,000 g per 9000 m, for example from 30,000 g to 38,000 g per 9000 m, for example 30,000 g, 32,000 g, 33,000 g, 37,000 g or 40,000 g per 9000 m.

In the case of the filtering material being formed from two bales of tow, the total denier of the filtering material may be from around 40,000 to 100,000 g per 9000 m for example from 60,000 g to 80,000 g per 9000 m, for example from 60,000 g to 76,000 g per 9000 m, for example 60,000 g, 64,000 g, 66,000 g, 74,000 g or 80,000 g per 9000 m.

The filament denier may be from 5 g to 9 g per 9000 m, for example 5 g, 7.3 g, 8 g or 9.0 g per 9000 m.

Filtering material is typically described by reference to the filament denier, the total denier and the fibre cross section. For example, the filtering material may comprise tow having the following denier: 8.0Y40, 8.0Y32, 7.3Y33, or 9.0Y37. For example, filtering material having a denier of 8.0Y40 means that the filament denier is 8.0 g per 9000 m, the total denier is 40000 g per 9000 m and the filaments have a Y shaped cross section.

The filtering material may comprise a plasticiser. The filtering material may include a plasticiser in an amount of from about 12% to 24% by weight of the filtering material and plasticiser, for example about 14% to 22%, for example about 16% to 20%, for example about 17 to 19%, for example about 18% of the weight of the filtering material and plasticiser.

The amount of plasticiser present in the mouthpiece or filter element is calculated as a percentage of the total weight of the filtering material and plasticiser via the general equation presented below.

$\mathrm{Percentage}\mathrm{of}\mathrm{plasticiser}\%=\frac{\mathrm{amount}\mathrm{of}\mathrm{plasticiser}\left(g\right)}{\mathrm{amount}\mathrm{of}\mathrm{plasticiser}\left(g\right)+\mathrm{amount}\mathrm{of}\mathrm{filtering}\mathrm{material}\left(g\right)}\times 100$

In the case of fibrous filtering material such as filamentary tow, the plasticiser acts to harden the fibres of the filtering material. Hardening the fibres of the filtering material may improve the shape definition of the filter element, and in particular the definition of the channel. For example, the filtering material may comprise plasticised fibres, for example plasticised tow, for example plasticised cellulose acetate tow. The formation of plasticised tow is well known in the art. The plasticiser may be, for example, triacetin, triethyleneglycol diacetate (TEGDA) or polyethylene glycol (PEG). The plasticiser may be applied to the filtering material by spraying onto the surface of the filtering material using methods known in the art.

The filtering material may optionally include a binder material. The filtering material may optionally include a water soluble binder material. Examples of water soluble materials include water soluble polymer materials such as polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl ether, starches, polyethylene glycols and polypropylene glycols; blends of water soluble binders with plasticisers such as triacetin, triethyleneglycol diacetate (TEGDA), or polyethylene glycol

(PEG); and hot melt water soluble binders in particulate form. The inclusion of a water soluble binder material may further enhance the ability of the filter to be readily and swiftly degraded e.g. under environmental conditions.

The filtering material may include an additive. The additive may be a pigment, for example a pearlescent pigment or a thermo-chromatic pigment.

The additive may include an aerosol modifying agent (for example a flavourant). The flavouring agent may, for example, be menthol, spearmint, peppermint, nutmeg, cinnamon, clove, lemon, chocolate, peach, strawberry, vanilla etc. The aerosol modifying agent (e.g. flavourant) may be applied to the filtering material in liquid form. The aerosol modifying agent (e.g. flavourant) may be liquefied prior to application to the filtering material, for example by heating above the melting point, for example by mixing with a liquid carrier. The aerosol modifying agent (e.g. flavourant) may be mixed with and applied with a plasticiser, for example by spraying the mixture of smoke modifying agent (e.g. flavourant) and plasticiser onto the filtering material. A preferred aerosol modifying agent (e.g. flavourant) is menthol or clove.

The cooling element of the invention may be for use as part of an aerosol generating article, for example which may form part of a heated tobacco product.

In a further aspect of the present invention, there is provided an aerosol generating article comprising a cooling element according to any statement set out herein.

The aerosol generating article may be a heated aerosol generating system. The heated aerosol generating system may include a rod of tobacco material, a heating element, a power source, one or more cooling elements according to any statement set out above and a mouthpiece or filter element, for example according to any statement set out herein. The one or more cooling elements may be positioned downstream from the heating element and tobacco rod. In use, the tobacco rod is heated to thereby generate a heated aerosol. The heated aerosol then passes through the one or more cooling elements which act to cool the aerosol before it passes through the mouthpiece and into the user's mouth.

In the case of the cooling element comprising a first section, second section and a third section, the heating element may be housed within the channel in either the first section or the third section. The second section and remaining section act to cool the heated aerosol in use.

In a further aspect of the present invention there is provided a multiple rod comprising a plurality of cooling elements according to the invention arranged end-to-end in a mirror image relationship.

In a further aspect of the present invention, there is provided an apparatus for making a mouth piece, filter element or a cooling element for an aerosol generating article, the apparatus comprising: a shaping chamber having an inlet for receiving filtering material and an outlet for discharging a rod of filtering material, and a shaping rod; wherein the shaping rod is configured to rotate, wherein the shaping chamber comprises a curing zone extending longitudinally along at least part of the length of the shaping chamber; and wherein the shaping rod is configured to move (e.g. reciprocate) longitudinally between a first position in which the end of the shaping rod is positioned at an end of the curing zone and in which the shaping rod extends along the entire length of the curing zone; and a second position in which the end of the shaping rod is distanced longitudinally from the first position and in which the shaping rod does not extend along the entire length of the curing zone.

The curing zone extends transversely along the width of the shaping chamber.

The shaping rod may be configured to rotate about the central longitudinal axis of the shaping rod.

In the second position, the shaping rod may be configured not to extend into the curing zone.

The shaping chamber may comprise a substantially cylindrical hollow element, for example a cylindrical hollow element, the inner surface of the cylindrical hollow element being configured to shape filtering material to form a cylindrical rod of filtering material. The shaping chamber inlet may be longitudinally spaced from the shaping chamber outlet.

The curing zone may extend along the entire width and the entire length of the shaping chamber. Alternatively, the curing zone may extend along the entire width and part of the length of the shaping chamber.

The shaping rod may be configured to extend at least partially within the shaping chamber. For example, the shaping rod may be configured to protrude from the shaping chamber. The shaping rod may be configured to extend along the entire length of the shaping chamber. For example, in the first position the shaping rod may be configured to extend along the entire length of the shaping chamber, and in the second position the shaping rod may be configured to extend along part of the length of the shaping chamber. In the second position the shaping rod may be configured not to extend into the shaping chamber.

In the second position the shaping rod may be configured to extend along part of the length of the curing zone. Alternatively, in the second position the shaping rod may be configured to extend up to but not into the curing zone.

The applicant has found that an apparatus which includes a shaping rod configured to rotate about a longitudinal axis of the shaping chamber and which is also configured to reciprocate longitudinally as described herein, enables the production of a filter element or mouthpiece as described herein. It will be appreciated that control of the rate at which filtering material is advanced into the shaping chamber and the frequency at which the shaping rod reciprocates can control the relative lengths of the first section, second section and third section (if present) forming the filter element or mouthpiece of the present invention.

The shaping rod may be coupled to a first motor for rotating the shaping rod. The motor may be configured to rotate the shaping rod.

The shaping rod may be coupled to a second motor for moving the shaping rod between the first position and the second position. The motor may be configured to move the shaping rod between the first position and the second position. The shaping rod may be coupled to the second motor via a cam.

Preferably, the shaping rod has a non-circular transverse cross section. The non-circular transverse cross section may be a modified circle having one or more indentations, a cross shape or a rectangle.

Preferably, the apparatus comprises a heating element for applying heat to the filtering material to thereby cure the filtering material. Preferably, the shaping chamber comprises a heating element such that heat is applied to the filtering material within the curing zone. The heating element may apply heat in the form of a jet of hot air, infrared radiation or steam. Preferably, the heating element comprises a steam element for applying steam (or configured to apply steam) to the filtering material. The shaping chamber may comprise a steam element for applying (or configured to apply) steam to the filtering material within the curing zone. The steam element may be for applying (or configured to apply) steam directly to the filtering material within the curing zone. The shaping chamber may comprise a steam inlet for applying (or configured to apply) steam to the filtering material within the shaping chamber, for example within the curing zone.

The apparatus may comprise further heating elements (for example in the form of steam elements) for applying heat (for example in the form of steam) to the rod of filtering material.

The further heating elements or steam elements may be spaced longitudinally apart from the outlet of the shaping chamber.

The apparatus may comprise a stuffer jet which is for gathering (or configured to gather) the filtering material before the filtering material enters the shaping chamber. The stuffer jet may comprise an inlet for applying fast moving air, such as compressed air, to the filtering material,

The apparatus may comprise a filtering material expansion element which is for expanding or is configured to expand the filtering material before the filtering material enters the shaping chamber. For example, the filtering material expansion element is for blooming or is configured to bloom the filtering material. The shaping rod may extend through the filtering material expansion element. The applicant has found that including a filtering material expansion element enables the filtering material to twist as the shaping rod rotates which starts the channel formation before the filtering material enters the shaping chamber and thereby helps to improve the definition of the channel.

The filtering material expansion element may be between the stuffer jet and the shaping chamber. The stuffer jet and the shaping chamber may be longitudinally spaced such that filtering material expands into the space between the stuffer jet and the shaping chamber. The apparatus may comprise one or more air jet elements for applying (or configured to apply) fast moving air, such as compressed air, to the filtering material after the filtering material exits the shaping chamber.

The apparatus may comprise a plasticising element for applying (or configured to apply) plasticiser to the filtering material before the filtering material enters the shaping chamber. The plasticising element may be positioned longitudinally apart from the inlet of the shaping chamber.

The apparatus may comprise a wrapping element for wrapping (or configured to wrap) the longitudinally extending rod with a wrapper, for example a plug wrap.

The apparatus may comprise a cutting element for cutting (or configured to cut) the rod of filtering material.

In a further aspect of the present invention there is provided a method of making a mouth piece, filter element or cooling element for an aerosol generating article, the method comprising: advancing filtering material in a longitudinal direction; drawing the filtering material into and through a shaping chamber having an inlet for receiving filtering material and an outlet through which a rod of filtering material exits the chamber; wherein the shaping chamber comprises a curing zone extending longitudinally along at least part of the length of the chamber; moving (for example reciprocating) a shaping rod longitudinally between a first position in which the end of the shaping rod is positioned at an end of the curing zone and in which the shaping rod extends along the entire length of the curing zone; and a second position in which the end of the shaping rod is distanced longitudinally from the first position and in which the shaping rod does not extend along the entire length of the curing zone, rotating the shaping rod; such that in the first position the advancing filtering material advances through the space defined by the inner surface of the shaping chamber and the shaping rod to form a first section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a longitudinally extending channel having a non-circular transverse cross section which varies in the longitudinal direction by rotating about a longitudinal axis of the first section, and in the second position filtering material advances into the space defined by the end of the shaping rod, the inner surface of the chamber and the end of the curing zone to form a second section comprising a longitudinally extending core of filtering material; to thereby form a longitudinally extending rod of filtering material having alternating first and second sections.

The filtering material may advance continuously.

Preferably, the curing zone extends along the width of the shaping chamber.

The shaping chamber may comprise a substantially cylindrical (e.g. cylindrical) hollow element, for example a cylindrical hollow element, the inner surface of the cylindrical hollow element being configured to shape filtering material to form a cylindrical rod of filtering material. The substantially cylindrical hollow element comprises a curing zone extending laterally along the width of the substantially cylindrical element and longitudinally along at least part of the substantially cylindrical hollow element.

The outlet of the shaping chamber may be spaced longitudinally from the inlet of the shaping chamber.

The curing zone may extend along the entire length of the shaping chamber. Alternatively, the curing zone may extend along part of the length of the shaping chamber.

The shaping rod may extend at least partially within the shaping chamber. For example, the shaping rod may protrude from the shaping chamber. The shaping rod may extend along the entire length of the shaping chamber. For example, in the first position the shaping rod may extend along the entire length of the shaping chamber, and in the second position the shaping rod may extend along part of the length of the shaping chamber. In the second position, the shaping rod may not extend into the shaping chamber.

In the second position, the shaping rod may extend along part of the length of the curing zone. Alternatively, in the second position the shaping rod may extend up to but not into the curing zone.

It will be appreciated that control of the rate at which filtering material is advanced into the shaping chamber and the frequency at which the shaping rod reciprocates can control the relative lengths of the first section, second section and third sections forming the filter element, mouthpiece or cooling element of the present invention. The relative rates at which filtering material advances and the frequency at which the shaping rod reciprocates may be controlled by a controller using techniques known in the art.

The shaping rod may be rotated by a first motor coupled to the shaping rod.

The shaping rod may be moved (reciprocated) longitudinally between the first position and the second position by a second motor coupled to the shaping rod.

Preferably, the shaping rod has a non-circular transverse cross section. The non-circular transverse cross section may be a modified circle having one or more indentations, a cross shape or a rectangle.

Preferably, heat is applied to the filtering material within the curing zone. The heat may be applied in the form of steam, hot air or infrared radiation. Preferably, steam is applied directly to the filtering material within the curing zone.

The heat acts to cure the filtering material within the curing zone to thereby form a longitudinally extending rod of filtering material, for example a longitudinally extending cylindrical rod of filtering material which includes a longitudinal extending channel as described herein.

The method may comprise a step of applying plasticiser to the filtering material before the filtering material is drawn into the shaping chamber. The plasticiser may be applied to the filtering material at a plasticising station. The plasticiser may be sprayed on to the filtering material using techniques known in the art. Alternatively, the filtering material may be pre-plasticised by a separate plasticising process.

The plasticiser may be applied such that the filtering material includes plasticiser in an amount of from about 12% to 24% by weight of the filtering material and plasticiser, for example about 14% to 22%, for example about 16% to 20%, for example about 17 to 19%, for example about 18% of the weight of the filtering material and plasticiser.

The amount of plasticiser present in filtering material is calculated as a percentage of the total weight of the filtering material and plasticiser via the general equation presented below.

$\mathrm{Percentage}\mathrm{of}\mathrm{plasticiser}\%=\frac{\mathrm{amount}\mathrm{of}\mathrm{plasticiser}\left(g\right)}{\mathrm{amount}\mathrm{of}\mathrm{plasticiser}\left(g\right)+\mathrm{amount}\mathrm{of}\mathrm{filtering}\mathrm{material}\left(g\right)}\times 100$

The plasticiser may be, for example, triacetin, triethyleneglycol diacetate (TEGDA) or polyethylene glycol (PEG).

The filtering material used in the methods of the invention may be as defined according to any statement herein.

The method may comprise a step of expanding the filtering material before the filtering material enters the shaping chamber. The filtering material may expand into a space before entering the shaping chamber. The filtering material may expand from a narrow stream of filtering material into an broader (more disperse) stream of filtering material. The shaping chamber may condense the expanded filtering material to thereby form a rod of filtering material as described above.

The shaping rod may extend through the expanded filtering material.

The method may comprise a step of drawing the filtering material into a stuffer jet before entering the shaping chamber. The filtering material may be drawn into the stuffer jet before the step of expanding the filtering material. In such a configuration, the step of expanding the filtering material may comprise expanding the filtering material into a space between the stuffer jet and the shaping chamber. The stuffer jet may condense the filtering material into a narrow stream of filtering material. Upon exiting the stuffer jet, the filtering material may expand to form a broader (more disperse) stream of filtering material.

The applicant has found that a step of expanding the filtering material before the filtering material enters the shaping chamber helps the filtering material to twist as the shaping rod rotates which starts the channel formation before the filtering material enters the shaping chamber and helps to improve the definition of the channel.

The method may comprise a step of cutting the longitudinally extending rod of filtering material to form one or more filter elements, cooling elements or mouthpieces. It will be appreciated that the longitudinally extending rod of filtering material may be cut at regular intervals to form a filter element, mouthpiece or cooling element according to the present invention. The cutting frequency may be determined depending on the type of filter. The cutter may be controlled by a controller using techniques known in the art.

The cutting step may form a filter element, mouthpiece or cooling element having two or three sections as described herein. It will be appreciated that the timing of the cutting step combined with the speed at which the filtering material advances will determine whether the filter element, mouthpiece or cooling element formed includes two or three sections and also the configuration of those sections.

The method may comprise a step of wrapping the longitudinally extending rod with a wrapper, for example before the step of cutting.

The method may comprise a step of applying fast moving air, such as compressed air, to the rod of filtering material after it leaves the shaping chamber. The applicant has found that applying fast moving air to the rod of filtering material helps to further cure and harden the rod of filtering material.

Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a mouthpiece, filter element or cooling element according to the present invention.

FIG. 2 is an end view of a mouthpiece, filter element or cooling element according to the present invention.

FIG. 3 is a perspective view of a mouthpiece, filter element or cooling element according to the present invention.

FIG. 4 is a side view of a mouthpiece, filter element or cooling element according to the present invention.

FIG. 5 is a sectional view of a mouthpiece, filter element or cooling element shown in FIG. 3.

FIG. 6 is sectional view of a mouthpiece, filter element or cooling element according to the invention.

FIG. 7 is sectional view of a mouthpiece, filter element or cooling element according to the invention.

FIG. 8 is an end view of a mouthpiece, filter element or cooling element according to the invention.

FIG. 9 is a sectional view of a mouthpiece, filter element or cooling element according to the invention.

FIG. 10 is an end view of a mouthpiece, filter element or cooling element according to the invention.

FIG. 11 is a sectional view of a mouthpiece, filter element or cooling element according to the invention.

FIG. 12 is a perspective view of a mouthpiece, filter element or cooling element according to the invention.

FIG. 13 is a schematic view of an apparatus for making a mouthpiece, filter element or cooling element in use.

FIGS. 14a and 14b are sectional views of part of the apparatus for making a mouthpiece, filter element or cooling element in use.

FIG. 1 shows a perspective view of a mouthpiece, filter element or cooling element 100 for an aerosol generating device according to an embodiment of the present invention. The mouthpiece, filter element or cooling element 100 comprises a first section 110 and a second section 120. The first section 110 comprises a longitudinally extending core 112 of filtering material in the form of a cylindrical core of filtering material. The filtering material may be cellulose acetate, although it will be appreciated that other filtering materials are also suitable The cylindrical core 112 of filtering material forming the first section includes an outer surface 116 and an inner surface (shown as 118 in FIG. 2). The outer surface 116 defines the cylindrical core and the inner surface 118 defines a channel 114. The channel 114 extends from the free end of the first section 110 and extends along the entire length of the first section 110. In the case of a filter element or mouthpiece, the channel 114 extends from the mouth end. The channel 114 has a non-circular transverse cross section, and as shown in FIG. 1, the transverse cross section is a modified circle having two protuberant portions 119. The transverse cross section varies in the longitudinal direction by rotating about a longitudinal axis of the first section 110, for example about a longitudinal axis of the channel 114. The protuberant portions 119 are formed as ridges (as shown in FIG. 2) which extend helically about the longitudinal axis L. The ridges 119 extend along the inner surface 118 that defines the channel 114 and the ridges protrude from that inner surface. The two ridges 119 are integral with the inner surface 118 and are defined by the filtering material that makes up the core. As illustrated in FIG. 1, the channel is located centrally with respect to the core 112.

Integral with the first section 110 is the second section 120. The second section 120 comprises a longitudinally extending core 122 of filtering material in the form of a cylindrical core of filtering material. The filtering material may be cellulose acetate, although it will be appreciated that other filtering materials are also suitable. The filtering material forming the second section 120 is continuous and homogenous. The filtering material forming the second section 120 is the same type of filtering material that formed the first section. The second section does not include a channel. The cylindrical core of filtering material 122 is defined by an outer surface 126.

FIG. 2 shows an end view of the mouthpiece, filter element or cooling element shown in FIG. 1, which also amounts to the end view of the first section 110. FIG. 2 illustrates the ridges 119 in more detail.

FIG. 3 shows a perspective view of the first section as illustrated in FIG. 1. As shown in FIG. 3, the core 112 extends along the longitudinal axis (L), and the channel 114 extends along the longitudinal axis L of the core 112.

FIG. 4 shows a side view of the first section along the plane defined by the y and L axis shown in FIG. 3.

FIG. 5 shows a sectional view of the first section along line A-A, as shown in FIG. 4. The channel transverse cross section shown in FIG. 5 includes a modified circle having two diametrically opposed protuberant parts which extend from the edge of the circle towards the centre of the circle. The diametrically opposed protuberant parts correspond to the ridges 119 which extend helically about the longitudinal axis of the first section 110. As shown in FIG. 5, the transverse cross section of the channel 114 is rotated with respect to the channel cross section shown at the end of the first section as shown in FIG. 3.

The ridges 119 extend helically with respect to the longitudinal axis (L) of the first section 110, so the position of the ridges 119 with respect to the circumference of the channel 114 varies along the length of the first section 110.

FIG. 6 shows a further sectional view of the first section 110 along line B-B as shown in FIG. 4. As is shown in FIG. 6, the transverse cross section of the channel 114 is rotated with respect to both the transverse cross section shown in FIG. 5 and the end cross section shown in FIG. 3.

FIG. 7 shows a sectional view of the first section of a further filter element, mouth piece or cooling element 200 according to the present invention. The filter element or mouthpiece 200 shown in FIG. 7 is similar to that shown in FIGS. 5 and 6, but includes four ridges 219 extending along the inner surface of the core 214 helically about the longitudinal axis of the first section.

FIG. 8 shows an end view and FIG. 9 shows a sectional view of the first section of a further filter element, mouthpiece or cooling element 300 according to the present invention. The first section shown in FIGS. 7 and 8 is similar to that shown in FIGS. 1 to 6, but the first section shown in FIGS. 7 and 8 has a channel 314 having a rectangular transverse cross section. The transverse cross section of the channel varies in the longitudinal direction of the core by rotating about a longitudinal axis of the first section.

FIG. 10 shows an end view and FIG. 11 shows a sectional view of the first section of a further filter element, mouth piece or cooling element 400 according to the present invention. The first section shown in FIG. 10 is similar to that shown in FIGS. 1 to 8, but the first section shown in FIGS. 10 and 11 has a channel 414 having a cross shaped transverse cross section. The transverse cross section of the channel varies in the longitudinal direction of the core by rotating about a longitudinal axis of the first section.

FIG. 12 shows a further filter element, mouthpiece or cooling element 500 according to the present invention. The filter element, mouthpiece or cooling element 500 is similar to that shown in FIG. 1 but includes a third section 130 which is integral with the second section. The first section 110 and second section 120 are the same as described above with respect to FIGS. 1-6. The third section 130 is similar to the first section 110 and includes a longitudinally extending core of filtering material in the form of a cylindrical core 132 of filtering material. The cylindrical core 132 of filtering material forming the third section includes an outer surface 136 and an inner surface. The outer surface 136 defines the cylindrical core 132 and the inner surface defines a channel 134. The channel 134 extends from the free end of the third section 130 and extends along the entire length of the third section 130. In the case of a filter element or mouthpiece, the first section channel 114 extends from the mouth end. The channel 134 has a non-circular transverse cross section, and as shown in FIG. 1, the transverse cross section is a modified circle having two protuberant portions 139. The transverse cross section varies in the longitudinal direction by rotating about a longitudinal axis of the third section, for example about a longitudinal axis of the channel 134. The protuberant portions 139 are formed as ridges which extend helically about the longitudinal axis. The ridges 139 extend along the inner surface that defines the channel 134 and the ridges 139 protrude from that inner surface. The two ridges 139 are integral with the inner surface and are defined by the filtering material that makes up the core. As illustrated in FIG. 12, the channel is located centrally with respect to the core 132.

The applicant has found that the filter element shown in FIG. 12 may be particularly suitable for use in a heated tobacco product because the channel in the first section or the third section can house a heating element and the second section and remaining section which does not house the heating element can provide filtration of the aerosol as well as act as a cooling element to cool the aerosol.

Any of the mouthpieces or filter elements illustrated in FIGS. 1 to 12 may form part of a filter which is included in a smoking article such as a cigarette. Some smoking articles, such as those containing marijuana, include a mouthpiece as described herein.

During use, smoke travels through the mouthpiece or filter element, and the smoke takes a helical path within the channel which means that smoke emerging from the mouthpiece or filter element will continues to follow a helical path, for example in the mouth of the user. The helical path taken by the smoke affects the mouthfeel of the smoke. The second section provides additional filtration of the smoke and the second section may include an additive to modify the properties of the smoke.

Any of the mouthpieces or filter elements illustrated in FIGS. 1 to 12 may also form part of a heated tobacco product or an electronic cigarette.

The cooling element as illustrated in FIGS. 1 to 12 may form part of a heated aerosol generating system which may form part of a non-combustible product, such a heated tobacco product. A heated aerosol generating system typically includes a heating element, a power source, a rod of tobacco, one or more cooling elements and a mouthpiece. The cooling element described herein may be incorporated into the heated aerosol generating system between the mouthpiece and the tobacco rod. During use, the heating element heats the rod of tobacco to form an aerosol. The aerosol then passes into the cooling element and is cooled by the cooling element. Due to the configuration of the channel, the aerosol takes a helically path through the cooling element which reduces the temperature of the aerosol. In the case of the cooling element illustrated in FIG. 12, either the first or third section may house the heating element thereby enabling the heating element and cooling element to be included in a single element.

FIG. 13 is a schematic view of the method and apparatus for making the filter elements, mouthpieces or cooling elements as described with respect to FIGS. 1 to 12.

Referring to FIG. 13, the apparatus comprises a stuffer jet 20 configured to receive filtering material 10. Spaced longitudinally from the stuffer jet is a shaping chamber 30. The space between the stuffer jet and the shaping chamber defines a filtering material expansion element in the form of a tow blooming section 25, into which filtering material expands as the filtering material exits the stuffer jet 20. A shaping rod in the form of a mandrel 60 extends longitudinally through the centre of the stuffer jet 20, the tow blooming section 25 and into the shaping chamber 30. The mandrel 60 is coupled to a first motor 70 which is configured to cause the mandrel to rotate about the central longitudinal axis of the mandrel. A second motor 80 is coupled to the mandrel and is configured to cause the mandrel 60 to reciprocate in a longitudinal direction. It will be appreciated that for the second motor 80 to cause the mandrel 60 to reciprocate while also rotate at the same time, the second motor 80 is coupled to the first motor 70 such that the second motor 80 will cause the first motor 70 to reciprocate together with the mandrel 60. Spaced longitudinally from the shaping chamber 30 is an air jet element 40 which is configured to apply a stream of fast moving air, such as compressed air, to the rod of filtering material 50 after it exits the shaping chamber 30. Spaced longitudinally from the air jet element 40 is a cutter 90 which is configured to cut the rod of filtering material 50 into one or more filter elements, mouthpieces or cooling elements 100. The mandrel 60, stuffer jet 20, tow blooming section 25 and shaping chamber 30 are described in more detail below with respect to FIGS. 14a and 14b.

Referring to FIG. 13, the method of making the filter element, mouthpiece or cooling element 100 will now be described. Tow 10 is continuously advanced in the longitudinal direction L. The tow may be cellulose acetate or another suitable filtering material. The tow may be drawn from a bale and may be pre-processed. For example, plasticiser may be sprayed directly on to the tow at a plasticising station (not shown) using methods known in the art. Alternatively, plasticiser may have been applied to the bale of tow using a separate process prior to the bale of tow being formed.

The tow 10 is advanced and flattened before entering stuffer jet 20. The stuffer 20 jet is configured to draw and gather the tow. As the tow exits the stuffer jet 20 via the stuffer jet outlet, the tow expands into a gap between the outlet of the stuffer jet 20 and the inlet of the shaping chamber 30. The tow 10 continues to advance into the shaping chamber 30 which shapes the tow into a longitudinally extending cylindrical rod 50 of filtering material. A mandrel 60 extends longitudinally through the centre of the stuffer jet 20, tow expansion section 25 and into the shaping chamber 30. The tow 10 advances around the mandrel 60, such that the mandrel 60 forms a longitudinally extending channel within the forming rod of tow.

Rotation of the mandrel 60, as the tow 10 passes through the shaping chamber 30, forms a longitudinally extending channel in which the channel cross section varies in the longitudinal direction by rotating about the central longitudinal axis of the channel.

Reciprocation of the mandrel 60 forms alternating first and second sections in the rod of filtering material. The first section comprises a longitudinally extending core of filtering material including an outer surface defining the core and an inner surface defining a channel, as described with respect to FIGS. 1 to 12. The second section comprising a longitudinally extending core of filtering material that is continuous and homogenous and does not include a channel.

The tow 10 is cured within the shaping chamber 30 by steam.

After the rod of filtering material exits the shaping chamber 30, it is treated with a fast moving stream of air by air jet element 40 to further cure the rod of filtering material 50. The rod of filtering material is subsequently cut into individual filter elements, mouth pieces or cooling elements by cutter 90.

The process and apparatus for shaping the rod of filter material, shaping the channel and forming alternating first and second sections will now be described in further detail with reference to FIGS. 14a and 14b.

FIGS. 14a and 14b show the configuration of the stuffer jet, tow expansion element, and shaping chamber in use and in a first and second configuration.

FIG. 14a shows the mandrel 60 in a first position. FIG. 14a shows the stuffer jet 20 which is a funnel shaped element having an inlet 24 and an outlet 26 for filtering material such as tow 10, and an air inlet 22 for applying fast moving air to the tow 10. The inlet 24 of the stuffer jet 20 has a larger diameter than the outlet 26 such that the stuffer jet 20 is tapered. Fast moving air passes into the stuffer jet 20 via air inlet 22 and causes the tow to advance longitudinally into and through the stuffer jet 20 where the tow is condensed into a cylinder. After the tow exits the stuffer jet via the outlet 26, the tow 10 expands into the gap 25 between the stuffer jet outlet 26 and the inlet of the shaping chamber which is spaced longitudinally from the outlet 26 of the stuffer jet 20. The expanded tow continues to advance longitudinally and enters the shaping chamber 30. The shaping chamber includes an inlet into which expanded tow enters and an outlet from which a longitudinally extending rod 50 of filtering material exits the shaping chamber 30. The shaping chamber 30 includes a steam inlet 32 through which steam enters the shaping chamber. As shown in FIG. 13a the shaping chamber includes a curing zone 35 which extends along the longitudinal length of the shaping chamber and across the width of the shaping chamber 30. The mandrel 60 extends longitudinally through the centre of the stuffer jet 20, the tow expansion element 25 and along the entire length of the curing zone 35 within the shaping chamber 30, such that the end of the mandrel 60 is in line with the end of the curing zone 35.

In this first configuration, tow 10 passes through the annular space between the mandrel 60 and the inside surface of the shaping chamber 30 to thereby form a channel extending along the length of the curing zone 35. Steam is applied to the filtering material within the shaping chamber 30 to thereby cure the filtering material by hardening the filtering material such that a first section is formed which comprises a longitudinally extending core of filtering material having an outer surface defining the longitudinally extending core of filtering material and an inner surface defining a longitudinally extending channel.

FIG. 14b shows the mandrel 60 in a second position in which the mandrel 60 is positioned rearward of the mandrel shown in FIG. 14a. In the second position, the end of the mandrel 60 is distanced longitudinally from the first position the mandrel took as shown in FIG. 14a, and the mandrel 60 does not extend along the entire length of the curing zone 35. As shown in FIG. 14b, the mandrel 60 is withdrawn to outside of the curing zone 35. In the second position, tow 10 passes into the space defined by the end of the mandrel 60 and the inner surface of the shaping chamber 30 to form a second section comprising a longitudinally extending core of filtering material without a channel.

As shown in FIG. 14b, the first section has advanced forwards and has retained its shape, including the channel, due to the steam applied to the filtering material within the curing zone 35. Accordingly, the method forms alternating first and second sections. It will be appreciated that the filtering material is advanced at a rate which is correlated with the speed at which the mandrel reciprocates such that alternating first and second sections are formed. The relative speeds of the advancing filtering material and the mandrel may be controlled by a controller (not shown).

The shape of the mandrel determines the cross sectional shape of the channel. For example, the rod used to make the mouthpiece, filter element or cooling element shown in FIGS. 1 to 6 is a cylinder which includes two diametrically opposed grooves which extend along the length of the mandrel. The mandrel used to make the mouthpiece, filter element or cooling element shown in FIG. 7 is a cylinder having two pairs of diametrically opposed grooves. The mandrel used to make the mouth piece, filter element or cooling element shown in FIGS. 8 and 9 has a rectangular cross section, and the mandrel used to form the mouthpiece, filter element or cooling element shown in FIGS. 10 and 11 has a cross shaped cross section.

The channel shape is defined by the mandrel as explained above. At all times during the method, the mandrel is rotating. Rotation of the mandrel, as the filtering material passes through the shaping chamber, forms a longitudinally extending channel in which the channel cross section varies in the longitudinal direction by rotating about the central longitudinal axis of the channel. In the case of a mandrel which includes grooves, such as used to make the mouthpiece, filter element or cooling element shown in FIGS. 1 to 6, the grooves in the mandrel define ridges on the inner surface of the core that defines the channel. The rotation of the mandrel and consequently the rotation of the grooves causes ridges to form on the inner surface of core that defines the channel. The ridges extend along the inner surface and follow a helical path about the longitudinal axis of the channel. It is possible to vary the helical pitch of the ridges by controlling the rotational speed of the mandrel and the speed at which the tow is drawn through the shaping chamber. The depth and width of each ridge may be modified by varying the depth and width of each groove in the mandrel. If additional ridges are desired, then the mandrel may include additional grooves. For example, the mouth piece, filter element or cooling element shown in FIG. 7 makes use of a mandrel having four grooves.

The diameter of the channel at its widest point may be varied by changing the diameter of the rod at its widest point. Similarly, the diameter and shape of the core of filtering material may be varied by modifying the diameter and shape of the shaping chamber.

The applicant has found that including a tow expansion element may improve the channel definition because the expanded tow is able to twist before entering the shaping chamber which aids formation of the channel as described above.

It will be appreciated that while the mandrel extends through the stuffer jet and the tow blooming section, in these sections channel formation may begin, but there is no application of heat so the filtering material does not cure. This means that a second section which does not include a channel can still be formed when the mandrel is withdrawn to the second position.

The cutting step is timed according to the type of filter element, mouthpiece or cooling element desired. For example the cutting step could be timed to form filter elements, mouthpieces or cooling elements that include a first section and section such as shown in FIG. 1. The rod of filtering material may be cut through the centre of each first section to thereby form a filter element, mouthpiece or cooling element having a first, second and third section in which the first and third sections are shorter than the second section. The rod could be cut such that each filter element, mouthpiece or cooling element includes a first section, second section and third section of the same length.

Claims

1. A mouth piece, filter element or cooling element for an aerosol generating article comprising: a first section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the first section; a second section comprising a longitudinally extending core of filtering material; wherein the first section and the second section are adjacent and integral; wherein the channel has a non-circular transverse cross section which varies in the longitudinal direction by rotating about a longitudinal axis of the first section.

2. The mouth piece, filter element or cooling element according to claim 1, wherein the channel has a transverse cross section which is a modified circle having one or more protuberant portions extending towards the centre of the circle, a cross shape, or a rectangle; and/or wherein the inner surface comprises one or more ridges which extend helically about a longitudinal axis of the first section.

3. (canceled)

4. The mouth piece, filter element or cooling element according to claim 1, comprising a third section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the third section; for example wherein the third section channel has a non-circular transverse cross section which varies in the longitudinal direction by rotating about a longitudinal axis of the third section; for example wherein the third section channel has a transverse cross section which is a modified circle having one or more protuberant portions extending towards the centre of the circle, a cross shape, or a rectangle.

5-6. (canceled)

7. A mouth piece, filter element or cooling element for an aerosol generating article comprising: a first section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the first section; a second section comprising a longitudinally extending core of filtering material; wherein the inner surface comprises one or more ridge(s) which extend helically about a longitudinal axis of the first section; and wherein the first section and the second section are adjacent and integral.

8. The mouth piece, filter element or cooling element according to claim 7 comprising: a third section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the third section; for example, wherein the inner surface comprises one or more ridge(s) which extend helically about a longitudinal axis of the third section.

9. (canceled)

10. The mouth piece, filter element or cooling element according to claim 4, wherein the third section is adjacent to the second section and integral with the second section, such that the second section is between the first section and the third section.

11. The mouth piece, filter element or cooling element according to of claim 2, wherein the or each ridge extends along the entire length of the inner surface; and/or wherein the inner surface comprises two or more ridges.

12. (canceled)

13. The mouth piece filter element or cooling element according to claim 1, wherein the filtering material comprises a plasticiser.

14. A filter for an aerosol-generating article comprising a filter element according to claim 1.

15. A multiple rod comprising a plurality of mouthpieces, filter elements or cooling elements according to claim 1 joined end-to-end in a mirror image relationship.

16. An aerosol-generating article comprising a mouthpiece, filter element or cooling element according to claim 1 or a filter for an aerosol-generating article comprising the filter element.

17. (canceled)

18. An apparatus for making a mouth piece filter element or cooling element for an aerosol generating article, the apparatus comprising:

a shaping chamber having an inlet for receiving filtering material and an outlet for discharging a rod of filtering material; and a shaping rod; wherein the shaping rod is configured to rotate; wherein the shaping chamber comprises a curing zone extending longitudinally along at least part of the length of the shaping chamber; and wherein the shaping rod is configured to move longitudinally between a first position in which the end of the shaping rod is positioned at an end of the curing zone and the shaping rod extends along the entire length of the curing zone; and a second position in which the end of the shaping rod is distanced longitudinally from the first position and the shaping rod does not extend along the entire length of the curing zone.

19. The apparatus according to claim 18, wherein the shaping rod is coupled to a first motor for rotating the shaping rod; and/or wherein the shaping rod is coupled to a second motor for moving the shaping rod between the first and second position; and/or wherein the shaping chamber comprises a hollow substantially cylindrical element for shaping the filtering material; and/or wherein the shaping rod has a non-circular transverse cross section; for example wherein the non-circular transverse cross section is a modified circle having one or more indentations, a cross shape or a rectangle.

20-23. (canceled)

24. The apparatus according to claim 18, comprising a heating element for applying heat to the filtering material; and/or comprising a steam element for applying steam to the filtering material; for example wherein the shaping chamber comprises a steam element for applying steam to the filtering material within the curing zone.

25-26. (canceled)

27. The apparatus according to claim 18, comprising a cutting element for cutting the rod of filtering material; and/or comprising a plasticising element for applying plasticiser to the filtering material before the filtering material enters the shaping chamber.

28. (canceled)

29. A method of making a mouth piece, filter element or cooling element for an aerosol generating article, the method comprising:

advancing filtering material in a longitudinal direction;

drawing the filtering material into and through a shaping chamber, wherein the shaping chamber comprises an inlet for receiving filtering material and an outlet through which a rod of filtering material exits the shaping chamber; wherein the shaping chamber comprises a curing zone extending longitudinally along at least part of the length of the chamber;

moving a shaping rod longitudinally between a first position in which the end of the shaping rod is positioned at an end of the curing zone and the shaping rod extends along the entire length of the curing zone, and a second position in which the end of the shaping rod is distanced longitudinally from the first position, and the shaping rod does not extend along the entire length of the curing zone;

rotating the shaping rod; such that in the first position the advancing filtering material advances through the space defined by the inner surface of the chamber and the shaping rod to form a first section comprising a longitudinally extending core of filtering material having an outer surface and an inner surface, the inner surface defining a longitudinally extending channel having a non-circular transverse cross section which varies in the longitudinal direction by rotating about a longitudinal axis of the first section, and in the second position filtering material advances into the space defined by the end of the shaping rod, the inner surface of the chamber and the end of the curing zone to form a second section comprising a longitudinally extending core of filtering material; to thereby form a longitudinally extending rod of filtering material having alternating first and second sections.

30. The method according to claim 29, wherein heat is applied to the filtering material within the curing zone; and/or wherein steam is applied to the filtering material within the curing zone; and/or wherein the shaping chamber comprises a substantially cylindrical hollow element comprising an inlet for receiving filtering material and an outlet for discharging a rod of filtering material; and/or wherein shaping rod has a non-circular transverse cross section; for example wherein the non-circular transverse cross section is a modified circle having one or more indentations, a cross shape or a rectangle.

31-34. (canceled)

35. The method according to claim 29, comprising applying plasticiser to the filtering material before the filtering material is drawn into the shaping chamber; and/or comprising a step of expanding the filtering material before the filtering material enters the shaping chamber; and/or wherein the filtering material is drawn into a stuffer jet before entering the shaping chamber; and/or comprising a step of cutting the longitudinally extending rod of filtering material to form one or more filter element(s), mouthpiece(s) or cooling element(s).

36-38. (canceled)