JP2024517030A - Filter elements, mouthpieces and cooling elements - Google Patents

Abstract

Disclosed is a mouthpiece, filter element or cooling element (100) for an aerosol-generating article comprising: a first section (110) comprising a longitudinally extending core of filter material (112) having an outer surface (116) and an inner surface (118), the inner surface (118) defining a channel (114) extending longitudinally from an end of the first section (110); and a second section (120) comprising a longitudinally extending core of filter material (122), the first section (110) and the second section (120) being adjacent and integral, the channel (114) having a non-circular cross-section that varies longitudinally by rotation about the longitudinal axis of the first section (110).

Description

The use of tube filter elements and tube mouthpieces in smoking articles is well known in the art. Typically, a tube filter element comprises a cylindrical core of filter material that includes channels extending longitudinally from the end of the cylindrical core. Tube filter elements are usually included as part of a multi-segment filter, where the tube filter element is usually positioned at the mouth end of the smoking article to provide a distinctive end appearance. Thus, existing tube filters require a step of assembling the tube filter element with additional filter segments that require a complex assembly process. When incorporated into a smoking article, the tube filter allows smoke to exit the filter in a concentrated flow that is directed toward the user's tongue during use.

There is a need for tube filter elements that do not require assembly with additional filter segments and can be manufactured in a single continuous process. There is also a need for tube filters that have different sensory characteristics.

In recent years, non-combustion smoking products have become increasingly popular. Such products include heated tobacco products, also known as tobacco heating products or non-combustion heating 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 through a mouthpiece. The mouthpiece may act to mimic the sensory aspects of a traditional smoking article filter. Additionally, some non-combustion heating products include a cooling element that cools the aerosol before it reaches the mouthpiece. The cooling element is typically a separate element that requires assembly with other components to form the non-combustion smoking product.

In a first aspect of the invention, a mouthpiece or filter element for an aerosol-generating article is provided, comprising: a first section comprising a longitudinally extending core of filter material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the first section; and a second section comprising a longitudinally extending core of filter material, the first section and the second section being adjacent and integral, the channel having a non-circular cross-section that varies longitudinally by rotation about the longitudinal axis of the first section.

The channel may have a cross-section that is a modified circle, a cross, or a rectangle with one or more protruding portions extending toward the center of the circle.

The channel is configured such that its cross-section at a first location along the length of the longitudinally extending core of filter material can be rotated relative to an adjacent location along the length of the longitudinally extending core of filter material. It will be understood that the cross-section of the channel may be rotated 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 passing through the mouthpiece or filter element becomes adapted to take a non-linear path through the channel, e.g. a spiral or swirling path. In use, the mouthpiece or filter element of the present invention has been found to provide a different smoking sensation in which the smoke feels more dispersed in the mouth compared to a standard tube filter element or mouthpiece. Without wishing to be bound by theory, it is believed that the non-linear path taken by the smoke, e.g. a spiral or swirling path, results in these differences in sensory characteristics.

The applicant has found that by having a second section adjacent and integral to the first section, it is not necessary to use further separate filter segments to impart additional properties or functionality to 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 present invention is nevertheless suitable for being incorporated into a multi-segment filter if desired.

The channel may be a tube or a hole. Preferably, the channel is surrounded by a filter material.

A non-circular transverse channel cross-section can be varied longitudinally by rotating about the longitudinal axis of the channel, e.g., the central longitudinal axis of the channel.

The second section may comprise a longitudinally extending core of continuous or homogeneously distributed filter material. Preferably, the second section does not include channels such as tubes or holes.

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

The inner surface may include one or more ridges that extend helically about the longitudinal axis of the first section, e.g., about the longitudinal axis of the channel, e.g., about a central longitudinal axis of the channel. The one or more ridges protrude from the inner surface. The one or more ridges may be formed on the inner surface. The one or more ridges may be integral with the inner surface.

For a channel having a cross-section that is a modified circle with one or more protruding portions extending from the edge of the circle towards the centre of the circle, the channel has a substantially cylindrical shape and the inner surface defining the channel comprises one or more ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel.

In the case of a channel having a cross-section that is cruciform, the channel has a substantially cylindrical shape and the inner surface defining the channel comprises four ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel.

The mouthpiece or filter element may comprise a first section comprising a longitudinally extending core of filter material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the second section, and a second section comprising a longitudinally extending core of filter material, the inner surface comprising one or more ridges extending helically about the longitudinal axis of the first section, the first section and the second section being adjacent and integral.

The applicant has found that, in use, the presence of one or more ridges extending helically about the longitudinal axis of the first section provides a different and improved smoke mouthfeel compared to a standard tube mouthpiece or filter element having a constant longitudinal cross section.

The applicant has found that during use, aerosol in the form of smoke passing through the mouthpiece or filter element takes a helical or spiral path through the channels. In use, the mouthpiece or filter of the present invention has been found to provide a different smoking sensation in which the smoke feels more dispersed in the mouth compared to a standard tube filter element or mouthpiece. Without wishing to be bound by theory, it is believed that the helical path taken by the smoke leads to these differences in sensory characteristics.

Applicant has also found that filtration may be improved by including one or more ridges that extend helically about the longitudinal axis of the or each channel, as compared to filter elements that include channels having a uniform longitudinal cross-section. The one or more ridges may increase the surface area of the inner surface of the or each channel, thereby increasing the surface area for adsorption.

The applicant has found that by having a second section adjacent and integral to the first section, it is not necessary to use further separate filter segments to impart additional properties or functionality to 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 present invention is nevertheless suitable for being incorporated into a multi-segment filter.

The channel may be a tube or a hole. Preferably, the channel is surrounded by a filter material.

The non-circular transverse channel cross-section may vary longitudinally by rotating about the longitudinal axis of the channel, for example about 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 filter material is substantially cylindrical, e.g. cylindrical. The longitudinally extending core of filter material may have a circumference of between 14 mm and 25 mm.

The first section may have a non-constant wall thickness due to the presence of one or more ridges on the inner surface of the core. The wall thickness at the narrowest point may be 0.6 mm to 2.3 mm, for example 1.8 to 2.3 mm. Wall thickness is defined herein as the distance between the outer surface and the inner surface of the core in the longitudinal direction.

The channel may be substantially cylindrical. It will be appreciated that while the channel may be substantially cylindrical, the cross section may not be circular, but may be, for example, a cross, a rectangle, or a modified circle that includes one or more protruding portions extending from the edge of the circle toward the center of the circle.

Preferably, the channel extends from the mouth end of the core of filter material.

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

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

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 entire 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 0.2 to 1.5 mm.

The inner surface of the core may comprise one, two, three or four ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel. The inner surface of the core may comprise two or more ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel. Preferably, the inner surface of the core comprises two ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel.

The first section may include two or more channels, e.g., two, three, or four channels, extending longitudinally from the end of the core.

The 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 homogeneously distributed filter material. Preferably, the second section does not include channels such as tubes or holes.

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

Alternatively, the mouthpiece or filter element may comprise a third section comprising a longitudinally extending core of filter 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 channel of the third section may have a non-circular cross-section that varies longitudinally by rotation about the longitudinal axis of the third section.

The channel of the third section may have a cross section that is a modified circle, a cross, or a rectangle with one or more protruding portions extending toward the center of the circle. The third section may be adjacent to 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 channel in the third section may include one or more ridges that extend helically around the longitudinal axis of the third section.

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

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

The channels in the third section may be tubes or holes. Preferably, the channels in the third section are surrounded by a filter material.

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

The inner surface of the third section may include one or more ridges that extend helically about the longitudinal axis of the third section, e.g., about the longitudinal axis of the channel, e.g., about a central longitudinal axis of the channel. The one or more ridges protrude from the inner surface. The one or more ridges may be formed on the inner surface. The one or more ridges may be integral with the inner surface.

For a channel of the third section having a cross-section that is a modified circle with one or more protruding portions extending from an edge of the circle toward the center of the circle, the channel has a substantially cylindrical shape and the inner surface defining the channel includes one or more ridges that extend helically about the longitudinal axis of the third section, e.g., about the longitudinal axis of the channel, e.g., about the central longitudinal axis of the channel.

When the channel of the third section has a cross-section that is cruciform, the channel has a substantially cylindrical shape and the inner surface defining the channel comprises four ridges that extend helically around the longitudinal axis of the third section, e.g., around the longitudinal axis of the channel, e.g., around a central longitudinal axis of the channel.

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

Preferably, each longitudinally extending core of filter material is substantially cylindrical, e.g. cylindrical. The longitudinally extending core of filter material may have a circumference of between 14 mm and 25 mm.

The third section may have a non-constant wall thickness due to the presence of one or more ridges on the inner surface of the core. The wall thickness at the narrowest point may be 0.6 mm to 2.3 mm, for example 1.8 to 2.3 mm. Wall thickness is defined herein as the distance between the outer surface and the inner surface of the core in the longitudinal direction.

The channel of the third section may be substantially cylindrical. It will be appreciated that although the channel may be substantially cylindrical, the cross section may not be circular, but may be, for example, a cross, a rectangle, or a modified circle that includes one or more protruding portions extending from the edge of the circle toward the center of the circle.

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

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

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 entire 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 0.2 to 1.5 mm.

The inner surface of the core of the third section may comprise one, two, three or four ridges that extend helically around the longitudinal axis of the third section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel. The inner surface of the core may comprise two or more ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel. Preferably, the inner surface of the core of the third section comprises two ridges that extend helically around the longitudinal axis of the third section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel.

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

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

The filter material may be any material conventionally used in tobacco smoke filter manufacture, such as filament, fibrous, web or extruded materials. The filter material may be natural or synthetic filamentary tow, such as cotton, or polymers such as polyethylene, polypropylene, or cellulose acetate tow.

The filter material may be a thermoplastic or otherwise spinnable polymer, such as polypropylene, polyethylene terephthalate or polylactide. It may also be, for example, natural or synthetic staple fibers, raw cotton, web materials such as paper (usually creped) and synthetic nonwovens, as well as extruded materials (e.g. starch, synthetic foams). Preferably, the filter material is a material that can be solidified using a plasticizer. Preferably, the filter material comprises filamentary tows of cellulose acetate.

The total denier of the filter material may be about 20,000-100,000g per 9000m, for example 20,000-80,000g per 9000m, for example 20,000-50,000g per 9000m.

When the filter material is formed from a single bale of tows, the total denier of the filter material may be about 20,000 to 50,000g per 9000m, for example 30,000g to 40,000g per 9000m, for example 30,000g to 38,000g per 9000m, for example 30,000g, 32,000g, 33,000g, 37,000g or 40,000g per 9000m.

When the filter material is formed from a tow of two bales, the total denier of the filter material may be about 40,000 to 100,000g per 9000m, for example 60,000g to 80,000g per 9000m, for example 60,000g to 76,000g per 9000m, for example 60,000g, 64,000g, 66,000g, 74,000g or 80,000g per 9000m.

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

Filter materials are typically described with reference to filament denier, total denier, and fiber cross-section. For example, a filter material may include tows having a denier of 8.0Y40, 8.0Y32, 7.3Y33, or 9.0Y37. For example, a filter material having a denier of 8.0Y40 means that the filament denier is 8.0 g per 9000 m, the total denier is 40,000 g per 9000 m, and the filaments have a Y-shaped cross-section.

The filter material may include a plasticizer. The filter material may include a plasticizer in an amount of about 12% to 24% by weight of the filter material and plasticizer, such as about 14% to 22% by weight of the filter material and plasticizer, such as about 16% to 20% by weight, such as about 17% to 19% by weight, such as about 18% by weight.

The amount of plasticizer present in the mouthpiece or filter element is calculated as a percentage of the total weight of the filter material and plasticizer according to the general formula shown below.

In the case of fibrous filter materials, such as filamentary tow, the plasticizer acts to stiffen the fibers of the filter material. Stiffening the fibers of the filter material may improve the shape definition of the filter element, particularly the channel definition. For example, the filter material may include plasticized fibers, such as plasticized tow, such as plasticized cellulose acetate tow. Formation of plasticized tow is well known in the art. The plasticizer may be, for example, triacetin, triethylene glycol diacetate (TEGDA) or polyethylene glycol (PEG). The plasticizer may be applied to the filter material by spraying onto the surface of the filter material using methods well known in the art.

The filter material may optionally include a binder material. The filter material may optionally include a water-soluble binder material. Examples of water-soluble materials include water-soluble polymeric materials such as polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl ether, starch, polyethylene glycol, polypropylene glycol, blends of water-soluble binders with plasticizers such as triacetin, triethylene glycol diacetate (TEGDA), or polyethylene glycol (PEG), and hot melt water-soluble binders in particulate form. The inclusion of a water-soluble binder material can further enhance the ability of the filter to be easily and quickly degraded under environmental conditions, for example.

The filter material may include an additive. The additive may be a particulate additive. The particulate additive may be any particulate additive suitable for use in smoke filters, such as activated carbon, zeolite, ion exchange resins (e.g., weakly basic anion exchange resins), sepiolite, silica gel, alumina, molecular sieves, carbonaceous polymer resins, and diatomaceous earth. The particulate additive may be a mixture of two or more materials. The additive may be a pigment, such as a pearlescent pigment or a thermochromatic pigment.

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

The mouthpiece or filter element may be for use as part of a tobacco smoke filter, or a filter for non-tobacco smokable materials, e.g., marijuana. The mouthpiece or filter element may be for use as part of a co-combustion tobacco product, such as a tobacco heating product device.

The mouthpiece or filter element of the present invention may be incorporated into a smoking article, such as a cigarette, cigarillo, or cigar. The mouthpiece or filter element of the present invention may be incorporated into a tobacco heating product or an electronic cigarette. The mouthpiece or filter element may also be used alone or as part of a filter that is assembled by a user to form a smoking article, such as 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 according to any of the above descriptions may be joined with a further filter element containing an additive, such as a granular additive, such as activated carbon granules. A mouthpiece or filter element of the present invention may be joined with a filter element comprising a capsule, such as a frangible capsule, such as a capsule containing a flavoring agent. A mouthpiece or filter element of the present invention may be joined with a filter element containing a flavoring agent, such as (menthol) or multiple flavoring agents.

In a further aspect of the invention, there is provided a filter for an aerosol-generating article, e.g. a tobacco smoke filter, comprising a filter element according to any of the above descriptions. The filter, e.g. a tobacco smoke filter, may further comprise one or more further filter elements. Such a filter comprising two or more filter elements may be referred to as a multi-segment filter.

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

One or more of the further filter elements may include a 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 encapsulated within the filter material, for example, as individual pockets or pods of particulate additive particles substantially separate from and fully encapsulated within the filter material. In another example, the fully enclosed (e.g., embedded) pocket(s) of additive may be one or more frangible capsules or one or more frangible microcapsules. The capsule(s) or microcapsule(s) may contain various media, for example, smoke modifiers, such as flavorants (such as those disclosed above), and/or liquids, solids, or other materials, for example, to aid in smoke filtration.

The one or more additional filter elements may include a flavoring agent provided in and/or on the thread. "Flavor thread" filter elements are well known in the art. Such filter elements typically incorporate an internally longitudinally aligned thread or tape element that carries a smoke modifier, such as a flavoring agent.

The filter may include an outer wrapper, for example plug wrap, surrounding the filter element or one or more filter elements. The wrapper may be paper, for example air permeable paper. The wrapper may have a weight of 20 to 50 grams per square meter, for example 27 to 35 grams per square meter. A particulate additive as described above may be applied to the wrapper or plug wrap surrounding the filter material, for example as described in GB 2261152. The further filter element may be wrapped by an outer wrapper, for example plug wrap, surrounding the further filter element. The filter element and the further filter element defined according to any of the above statements may be wrapped together by an outer wrapper, such as plug wrap. The outer wrapper may function to join the filter elements and secure them in place.

In a further aspect of the 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 comprise a filter as described above joined to a wrapped rod of smoking material, such as tobacco smoking material. Generally, for smoking articles comprising marijuana smoking material, the smoking article comprises a mouthpiece according to any of the above descriptions. The smoking article may further comprise a tipping wrapper, e.g., tipping paper. The tipping wrapper joins the wrapped rod of smoking material to the filter or mouthpiece by engaging around adjacent ends of the filter or mouthpiece and the wrapped rod of smoking material. The tipping wrapper may be configured to leave a portion 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 that engages around the entire length of the filter or mouthpiece and the adjacent ends 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 known in the art, for example by the use of pre-perforated or air-permeable filter wrappers (plug wrap) or tipping wrappers (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 the filter material (and the wrapper(s) (plug wrap) and tipping wrapper (tipping paper), if present). The breathable full tipping wrapper (tipping paper) may likewise be essentially air-permeable or may be provided with ventilation holes, and in the case of breathable products in which both the filter wrapper (plug wrap) and the tipping wrapper (tipping paper) are present, the ventilation through the tipping wrapper (tipping paper) usually coincides with the ventilation through the filter wrapper (plug wrap). Vents through the filter wrapper (plug wrap), or through the tipping wrapper (tipping paper), or both simultaneously, may be created by laser drilling during manufacture of the mouthpiece, filter, or filter element.

In a further aspect of the 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 of the above descriptions. The one or more cooling elements may be positioned downstream from the heating element and the tobacco rod. In use, the tobacco rod is heated, thereby generating a heated aerosol. The heated aerosol then passes through one or more cooling elements which act to cool the aerosol before it passes through the mouthpiece and into the user's mouth.

As used herein, aerosol-generating articles may include smoking articles such as cigarettes, cigars, cigarillos, roll-your-own cigarettes, heated tobacco products such as non-combustion heating devices and tobacco heating devices, and electronic cigarettes.

In a further aspect of the invention, a cooling element for an aerosol-generating article is provided, comprising a first section comprising a longitudinally extending core of filter material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the first section, and a second section comprising a longitudinally extending core of filter material, the first section and the second section being adjacent and integral, the channel having a non-circular cross-section that varies longitudinally by rotation about the longitudinal axis of the first section.

The channel may have a cross-section that is a modified circle, a cross, or a rectangle with one or more protruding portions extending toward the center of the circle.

The channel is configured such that its cross-section at a first location along the length of the longitudinally extending core of filter material can be rotated relative to an adjacent location along the length of the longitudinally extending core of filter material. It will be understood that the cross-section of the channel may be rotated more or less than 360 degrees along the length of the channel.

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

The channel may be a tube or a hole. Preferably, the channel is surrounded by a filter material.

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

The second section may comprise a longitudinally extending core of continuous or homogeneously distributed filter material. Preferably, the second section does not include channels such as tubes or holes.

The inner surface may include one or more ridges that extend helically about the longitudinal axis of the first section, e.g., about the longitudinal axis of the channel, e.g., about a central longitudinal axis of the channel. The one or more ridges protrude from the inner surface. The one or more ridges may be formed on the inner surface. The one or more ridges may be integral with the inner surface.

For a channel having a cross-section that is a modified circle with one or more protruding portions extending from the edge of the circle towards the centre of the circle, the channel has a substantially cylindrical shape and the inner surface defining the channel comprises one or more ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel.

In the case of a channel having a cross-section that is cruciform, the channel has a substantially cylindrical shape and the inner surface defining the channel comprises four ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel.

The cooling element may comprise a first section comprising a longitudinally extending core of filter material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the second section, and a second section comprising a longitudinally extending core of filter material, the inner surface comprising one or more ridges extending helically about the longitudinal axis of the first section, the first section and the second section being adjacent and integral.

The channel may be a tube or a hole. Preferably, the channel is surrounded by a filter material.

The non-circular transverse channel cross-section may vary longitudinally by rotating about the longitudinal axis of the channel, for example about 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 filter material is substantially cylindrical, e.g. cylindrical. The longitudinally extending core of filter material may have a circumference of between 14 mm and 25 mm.

The first section may have a non-constant wall thickness due to the presence of one or more ridges on the inner surface of the core. The wall thickness at the narrowest point may be 0.6 mm to 2.3 mm, for example 1.8 to 2.3 mm. Wall thickness is defined herein as the distance between the outer surface and the inner surface of the core in the longitudinal direction.

The channel may be substantially cylindrical. It will be appreciated that while the channel may be substantially cylindrical, the cross section may not be circular, but may be, for example, a cross, a rectangle, or a modified circle that includes one or more protruding portions extending from the edge of the circle toward the center of the circle.

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

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

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 entire 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 0.2 to 1.5 mm.

The inner surface of the core may comprise one, two, three or four ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel. The inner surface of the core may comprise two or more ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel. Preferably, the inner surface of the core comprises two ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel.

The cooling element may have two or more channels extending longitudinally from the end of the core, for example, two, three, or four channels.

The cooling element may have a circumference of 14-25mm.

The length of the 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 homogeneously distributed filter material. Preferably, the second section does not include channels such as tubes or holes.

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

Alternatively, the mouthpiece or filter element may comprise a third section comprising a longitudinally extending core of filter 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 channel of the third section may have a non-circular cross-section that varies longitudinally by rotation about the longitudinal axis of the third section. The channel may have a cross-section that is a modified circle, a cross, or a rectangle with one or more protruding portions that extend toward the center of the circle. The third section may be adjacent to and integral with the second section such that the second section is between the first and third sections.

The inner surface of the channel in the third section may include one or more ridges that extend helically around the longitudinal axis of the third section.

The third section may be adjacent to 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 a free end of the third section. The third section may be substantially the same as the first section. The channel of the third section is configured such that its cross-section at a first location along the length of the longitudinally extending core of the filter material may be rotated relative to an adjacent location along the length of the longitudinally extending core of the filter material. It will be appreciated that the cross-section of the channel may be rotated more or less than 360 degrees along the length of the channel.

The channels in the third section may be tubes or holes. Preferably, the channels in the third section are surrounded by a filter material.

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

The inner surface of the third section may include one or more ridges that extend helically about the longitudinal axis of the third section, e.g., about the longitudinal axis of the channel, e.g., about a central longitudinal axis of the channel. The one or more ridges protrude from the inner surface. The one or more ridges may be formed on the inner surface. The one or more ridges may be integral with the inner surface.

For a channel of the third section having a cross-section that is a modified circle with one or more protruding portions extending from an edge of the circle toward the center of the circle, the channel has a substantially cylindrical shape and the inner surface defining the channel includes one or more ridges that extend helically about the longitudinal axis of the third section, e.g., about the longitudinal axis of the channel, e.g., about the central longitudinal axis of the channel.

When the channel of the third section has a cross-section that is cruciform, the channel has a substantially cylindrical shape and the inner surface defining the channel comprises four ridges that extend helically around the longitudinal axis of the third section, e.g., around the longitudinal axis of the channel, e.g., around a central longitudinal axis of the channel.

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

Preferably, each longitudinally extending core of filter material is substantially cylindrical, e.g. cylindrical. The longitudinally extending core of filter material may have a circumference of between 14 mm and 25 mm.

The third section may have a non-constant wall thickness due to the presence of one or more ridges on the inner surface of the core. The wall thickness at the narrowest point may be 0.6 mm to 2.3 mm, for example 1.8 to 2.3 mm. Wall thickness is defined herein as the distance between the outer surface and the inner surface of the core in the longitudinal direction.

The channel of the third section may be substantially cylindrical. It will be appreciated that although the channel may be substantially cylindrical, the cross section may not be circular, but may be, for example, a cross, a rectangle, or a modified circle that includes one or more protruding portions extending from the edge of the circle toward the center of the circle.

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

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

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 entire 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 0.2 to 1.5 mm.

The inner surface of the core of the third section may comprise one, two, three or four ridges that extend helically around the longitudinal axis of the third section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel. The inner surface of the core may comprise two or more ridges that extend helically around the longitudinal axis of the first section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel. Preferably, the inner surface of the core of the third section comprises two ridges that extend helically around the longitudinal axis of the third section, e.g. around the longitudinal axis of the channel, e.g. around the central longitudinal axis of the channel.

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

Applicant has found that a cooling element including a first section, a second section, and a third section as described herein can accommodate a heating element within a channel of either the first section or the third section. In such a case, the second section and the remaining sections can act to cool the aerosol formed by the heating element.

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

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

The filter material may be any material conventionally used in tobacco smoke filter manufacture, such as filament, fibrous, web or extruded materials. The filter material may be natural or synthetic filamentary tow, such as cotton, or polymers such as polyethylene, polypropylene, or cellulose acetate tow.

The filter material may be a thermoplastic or otherwise spinnable polymer, such as polypropylene, polyethylene terephthalate or polylactide. It may also be, for example, natural or synthetic staple fibers, raw cotton, web materials such as paper (usually creped) and synthetic nonwovens, as well as extruded materials (e.g. starch, synthetic foams). Preferably, the filter material is a material that can be solidified using a plasticizer. Preferably, the filter material comprises filamentary tows of cellulose acetate.

The total denier of the filter material may be about 20,000-100,000g per 9000m, for example 20,000-80,000g per 9000m, for example 20,000-50,000g per 9000m.

When the filter material is formed from a single bale of tows, the total denier of the filter material may be about 20,000 to 50,000g per 9000m, for example 30,000g to 40,000g per 9000m, for example 30,000g to 38,000g per 9000m, for example 30,000g, 32,000g, 33,000g, 37,000g or 40,000g per 9000m.

When the filter material is formed from a tow of two bales, the total denier of the filter material may be about 40,000 to 100,000g per 9000m, for example 60,000g to 80,000g per 9000m, for example 60,000g to 76,000g per 9000m, for example 60,000g, 64,000g, 66,000g, 74,000g or 80,000g per 9000m.

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

Filter materials are typically described with reference to filament denier, total denier, and fiber cross-section. For example, a filter material may include tows having a denier of 8.0Y40, 8.0Y32, 7.3Y33, or 9.0Y37. For example, a filter material having a denier of 8.0Y40 means that the filament denier is 8.0 g per 9000 m, the total denier is 40,000 g per 9000 m, and the filaments have a Y-shaped cross-section.

The filter material may include a plasticizer. The filter material may include a plasticizer in an amount of about 12% to 24% by weight of the filter material and plasticizer, such as about 14% to 22% by weight of the filter material and plasticizer, such as about 16% to 20% by weight, such as about 17% to 19% by weight, such as about 18% by weight.

The amount of plasticizer present in the mouthpiece or filter element is calculated as a percentage of the total weight of the filter material and plasticizer according to the general formula shown below.

In the case of fibrous filter materials, such as filamentary tow, the plasticizer acts to stiffen the fibers of the filter material. Stiffening the fibers of the filter material may improve the shape definition of the filter element, particularly the channel definition. For example, the filter material may include plasticized fibers, such as plasticized tow, such as plasticized cellulose acetate tow. Formation of plasticized tow is well known in the art. The plasticizer may be, for example, triacetin, triethylene glycol diacetate (TEGDA) or polyethylene glycol (PEG). The plasticizer may be applied to the filter material by spraying onto the surface of the filter material using methods well known in the art.

The filter material may optionally include a binder material. The filter material may optionally include a water-soluble binder material. Examples of water-soluble materials include water-soluble polymeric materials such as polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl ether, starch, polyethylene glycol, polypropylene glycol, blends of water-soluble binders with plasticizers such as triacetin, triethylene glycol diacetate (TEGDA), or polyethylene glycol (PEG), and hot melt water-soluble binders in particulate form. The inclusion of a water-soluble binder material can further enhance the ability of the filter to be easily and quickly degraded under environmental conditions, for example.

The filter material may include an additive. The additive may be a pigment, for example a pearlescent pigment or a thermochromatic pigment.

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

The cooling element of the present invention may be intended for use as part of an aerosol-generating article, for example forming 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 of the descriptions 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 of the descriptions above, and a mouthpiece or filter element, for example, according to any of the descriptions herein. The one or more cooling elements may be positioned downstream from the heating element and the tobacco rod. In use, the tobacco rod is heated, thereby generating a heated aerosol. The heated aerosol then passes through one or more cooling elements which act to cool the aerosol before it passes through the mouthpiece and into the mouth of the user.

In the case of a cooling element including a first section, a second section and a third section, the heating element may be housed within a channel in either the first section or the third section. The second section and the remaining sections 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 present invention arranged end-to-end in a mirror image relationship.

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

The curing zone extends laterally along the width of the forming chamber.

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

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

The forming chamber may comprise a substantially cylindrical hollow element, e.g., a cylindrical hollow element, the inner surface of which is configured to form the filter material to form a cylindrical rod of filter material. The forming chamber inlet may be longitudinally spaced from the forming chamber outlet.

The curing zone may extend along the entire width and length of the molding chamber. Alternatively, the curing zone may extend along a portion of the entire width and length of the molding chamber.

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

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

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

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

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

Preferably, the molded rod has a non-circular cross-section. The non-circular cross-section may be a modified circle, a cross or a rectangle having one or more depressions.

Preferably, the apparatus comprises a heating element for applying heat to the filter material, thereby hardening the filter material. Preferably, the moulding chamber comprises a heating element such that heat is applied to the filter material in the hardening zone. The heating element may apply heat in the form of hot air, infrared radiation or a jet of steam. Preferably, the heating element comprises a steam element for applying steam (or configured to apply steam) to the filter material. The moulding chamber may comprise a steam element for applying steam (or configured to apply steam) to the filter material in the hardening zone. The steam element may be for applying steam (or configured to apply steam) directly to the filter material in the hardening zone. The moulding chamber may comprise a steam inlet for applying steam (or configured to apply steam) to the moulding chamber, e.g. to the filter material in the hardening zone.

The apparatus may comprise a further heating element (e.g. in the form of a steam element) for applying heat (e.g. in the form of steam) to the rod of filter material. The further heating element or steam element may be spaced longitudinally from the outlet of the forming chamber.

The apparatus may include a stuffer jet for collecting (or configured to collect) the filter material before it enters the forming chamber. The stuffer jet may include an inlet for applying fast moving air, such as compressed air, to the filter material.

The apparatus may include a filter material expansion element for or configured to expand the filter material before the filter material enters the forming chamber. For example, the filter material expansion element is for or configured to bloom the filter material. The forming rod may extend through the filter material expansion element. Applicant has found that including the filter material expansion element allows the filter material to twist as the forming rod rotates, thereby initiating channel formation before the filter material enters the forming chamber, thereby helping to improve channel definition.

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

The apparatus may include a plasticizing element that applies (or is configured to apply) a plasticizer to the filter material before the filter material enters the forming chamber. The plasticizing element may be positioned longitudinally away from the entrance to the forming chamber.

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

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

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

The filter material may advance continuously.

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

The forming chamber may comprise a substantially cylindrical (e.g., cylindrical) hollow element, e.g., a cylindrical hollow element, the inner surface of which is configured to form the filter material to form a cylindrical rod of filter material. The substantially cylindrical hollow element includes a hardening zone extending laterally along a width of the substantially cylindrical element and longitudinally along at least a portion of the substantially cylindrical hollow element.

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

The curing zone may extend along the entire length of the molding chamber. Alternatively, the curing zone may extend along only a portion of the length of the molding chamber.

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

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

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

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

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

Preferably, the molded rod has a non-circular cross-section. The non-circular cross-section may be a modified circle, a cross or a rectangle having one or more depressions.

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

The heat acts to harden the filter material within the hardening zone, thereby forming a longitudinally extending rod of filter material, e.g., a longitudinally extending cylindrical rod of filter material including longitudinally extending channels as described herein.

The method may include applying a plasticizer to the filter material before it is drawn into the molding chamber. The plasticizer may be applied to the filter material at a plasticizing station. The plasticizer may be sprayed onto the filter material using techniques known in the art. Alternatively, the filter material may be pre-plasticized by a separate plasticizing process.

The plasticizer may be applied such that the filter material comprises plasticizer in an amount of about 12% to 24% by weight of the filter material and plasticizer, such as about 14% to 22% by weight of the filter material and plasticizer, such as about 16% to 20% by weight, such as about 17% to 19% by weight, such as about 18% by weight.

The amount of plasticizer present in the filter material is calculated as a percentage of the total weight of the filter material and plasticizer according to the general formula shown below.

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

The filter material used in the method of the present invention may be as defined by any description herein.

The method may include expanding the filter material before it enters the forming chamber. The filter material may expand into the space before it enters the forming chamber. The filter material may expand from a narrow stream of filter material to a wider (more dispersed) stream of filter material. The forming chamber may condense the expanded filter material, thereby forming a rod of filter material as described above.

The shaped rod may extend through the expanded filter material.

The method may include drawing the filter material into the stuffer jet before it enters the forming chamber. The filter material may be drawn into the stuffer jet before the step of expanding the filter material. In such a configuration, the step of expanding the filter material may include expanding the filter material into a space between the stuffer jet and the forming chamber. The stuffer jet may condense the filter material into a narrow stream of filter material. Upon exiting the stuffer jet, the filter material may expand to form a wider (more dispersed) stream of filter material.

Applicant has found that the step of expanding the filter material before it enters the forming chamber helps the filter material to twist as the forming rod rotates, initiating channel formation before the filter material enters the forming chamber and helping to improve channel definition.

The method may include cutting a longitudinally extending rod of filter material to form one or more filter elements, cooling elements, or mouthpieces. It will be appreciated that the longitudinally extending rod of filter material may be cut at regular intervals to form filter elements, mouthpieces, or cooling elements according to the present invention. The frequency of cutting may depend 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 filter material advances will determine whether the filter element, mouthpiece, or cooling element formed includes two or three sections, as well as the configuration of those sections.

The method may include, for example, wrapping the longitudinally extending rod in a wrapper prior to the cutting step.

The method may include the step of applying fast moving air, such as compressed air, to the rod of filter material after it exits the forming chamber. Applicant has found that applying fast moving air to the rod of filter material helps to further stiffen and harden the rod of filter material.

A preferred embodiment of the present 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. 1 is a perspective view of a mouthpiece, filter element or cooling element according to the present invention. FIG. 2 is a side view of a mouthpiece, filter element or cooling element according to the present invention. FIG. 4 is a cross-sectional view of the mouthpiece, filter element or cooling element shown in FIG. FIG. 2 is a cross-sectional view of a mouthpiece, filter element or cooling element according to the present invention. FIG. 2 is a cross-sectional 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. 2 is a cross-sectional 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. 2 is a cross-sectional view of a mouthpiece, filter element or cooling element according to the present invention. FIG. 1 is a perspective view of a mouthpiece, filter element or cooling element according to the present invention. FIG. 1 is a schematic diagram of an apparatus for making a mouthpiece, a filter element or a cooling element in use. FIG. 2 is a cross-sectional view of a portion of an apparatus for making a mouthpiece, filter element or cooling element in use. FIG. 2 is a cross-sectional view of a portion of an apparatus for making a mouthpiece, filter element or cooling element in use.

1 shows a perspective view of a mouthpiece, filter element or cooling element 100 for an aerosol generating device according to one embodiment of the present invention. The mouthpiece, filter element or cooling element 100 includes a first section 110 and a second section 120. The first section 110 includes a longitudinally extending core 112 of filter material in the form of a cylindrical core of filter material. The filter material may be cellulose acetate, although it will be understood that other filter materials are suitable. The cylindrical core 112 of filter 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 a 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 cross-section, which is a modified circle with two protruding portions 119, as shown in FIG. 1. The cross-section varies longitudinally around the longitudinal axis of the first section 110, for example by rotating around the longitudinal axis of the channel 114. The protruding portion 119 is formed as a ridge (as shown in FIG. 2) that extends in a spiral manner around the longitudinal axis L. The ridge 119 extends along and protrudes from the inner surface 118 that defines the channel 114. The two ridges 119 are integral with the inner surface 118 and are defined by the filter material that constitutes the core. As shown in FIG. 1, the channel is centrally located with respect to the core 112.

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

Figure 2 shows an end view of the mouthpiece, filter element or cooling element shown in Figure 1, which is also an end view of the first section 110. Figure 2 shows the ridge 119 in more detail.

Figure 3 shows a perspective cross-sectional view of the first section shown in Figure 1. As shown in Figure 3, the core 112 extends along a longitudinal axis (L) and the channel 114 extends along the longitudinal axis L of the core 112.

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

Figure 5 shows a cross-sectional view of the first section taken along line A-A as shown in Figure 4. The channel cross-section shown in Figure 5 comprises a modified circle with two diametrically opposed protrusions extending from the edge of the circle towards the center of the circle. The diametrically opposed protrusions correspond to ridges 119 that extend helically about the longitudinal axis of the first section 110. As shown in Figure 5, the cross-section of the channel 114 is rotated relative to the channel cross-section shown at the end of the first section as shown in Figure 3.

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

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

Figure 7 shows a cross-sectional view of a first section of a further filter element, mouthpiece or cooling element 200 according to the invention. The filter element or mouthpiece 200 shown in Figure 7 is similar to that shown in Figures 5 and 6, but includes four ridges 219 that extend helically around the longitudinal axis of the first section along the inner surface of the core 214.

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

Figure 10 shows an end view and Figure 11 shows a cross-sectional view of a first section of a further filter element, mouthpiece or cooling element 400 according to the invention. The first section shown in Figure 10 is similar to that shown in Figures 1 to 8, but the first section shown in Figures 10 and 11 has a channel 414 with a cross-shaped cross section. The cross section of the channel varies longitudinally of the core by rotating the first section about its longitudinal axis.

12 shows a further filter element, mouthpiece or cooling element 500 according to the invention. The filter element, mouthpiece or cooling element 500 is similar to that shown in FIG. 1, but includes a third section 130 integral with the second section. The first section 110 and the second section 120 are the same as those 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 filter material in the form of a cylindrical core 132 of filter material. The cylindrical core 132 of filter 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 a 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 channel 114 of the first section extends from the mouth end. The channel 134 has a non-circular cross-section, which is a modified circle with two protruding portions 139, as shown in FIG. 1. The cross-section varies longitudinally around the longitudinal axis of the third section, for example by rotating around the longitudinal axis of the channel 134. The protruding portion 139 is formed as a ridge that extends in a spiral manner around the longitudinal axis. The ridge 139 extends along the inner surface that defines the channel 134, and the ridge 139 protrudes from the inner surface. The two ridges 139 are integral with the inner surface and are defined by the filter material that constitutes the core. As shown in FIG. 12, the channel is centered with respect to the core 132.

Applicant has found that the filter element shown in FIG. 12 may be particularly suitable for use in a heated tobacco product because the channels in the first section or the third section may accommodate a heating element, and the second section and the remaining sections not accommodating a heating element may provide aerosol filtration as well as act as cooling elements to cool the aerosol.

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

During use, smoke travels through the mouthpiece or filter element and the smoke takes a spiral path within the channel, meaning that as the smoke exits the mouthpiece or filter element it continues to follow a spiral path, for example in the user's mouth. The spiral path the smoke takes affects the mouthfeel of the smoke. The second section provides additional filtration of the smoke and the second section may contain additives to modify the characteristics of the smoke.

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

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

Figure 13 is a schematic diagram of a method and apparatus for manufacturing the filter element, mouthpiece or cooling element described with respect to Figures 1 to 12.

13, the apparatus includes a stuffer jet 20 configured to receive the filter material 10. Spaced longitudinally from the stuffer jet is a forming chamber 30. The space between the stuffer jet and the forming chamber defines a filter material expansion element in the form of a tow blooming section 25 into which the filter material expands as it exits the stuffer jet 20. A forming rod in the form of a mandrel 60 extends longitudinally through the center of the stuffer jet 20, the tow blooming section 25, and into the forming chamber 30. The mandrel 60 is coupled to a first motor 70, which is configured to rotate the mandrel about a central longitudinal axis of the mandrel. A second motor 80 is coupled to the mandrel and configured to reciprocate the mandrel 60 longitudinally. It will be appreciated that the second motor 80 is coupled to the first motor 70 such that the second motor 80 reciprocates the first motor 70 with the mandrel 60 so that the second motor 80 reciprocates and simultaneously rotates the mandrel 60. An air jet element 40 is spaced longitudinally from the forming chamber 30 and configured to apply a stream of fast moving air, such as compressed air, to the rod of filter material 50 after it exits the forming chamber 30. A cutter 90 is spaced longitudinally from the air jet element 40 and configured to cut the rod of filter material 50 into one or more filter elements, mouthpieces or cooling elements 100. The mandrel 60, stuffer jet 20, tow blooming section 25 and forming chamber 30 are described in more detail below with respect to Figures 14a and 14b.

13, a method of making a filter element, mouthpiece or cooling element 100 is described. A tow 10 is continuously advanced in a longitudinal direction L. The tow may be cellulose acetate or another suitable filter material. The tow may be drawn from a bale and may be pre-treated. For example, a plasticizer may be sprayed directly onto the tow at a plasticizing station (not shown) using methods well known in the art. Alternatively, the plasticizer may have been applied to the bale of tow using a separate process before the bale of tow is formed.

The tow 10 is advanced and flattened before entering the stuffer jet 20. The jets of the stuffer 20 are configured to draw and collect the tow. As the tow exits the stuffer jet 20 through the stuffer jet outlet, the tow expands into the gap between the outlet of the stuffer jet 20 and the inlet of the forming chamber 30. The tow 10 continues to advance into the forming chamber 30, which forms the tow into a longitudinally extending cylindrical rod 50 of filter material. The mandrel 60 extends longitudinally through the center of the stuffer jet 20, the tow expansion section 25, and into the forming chamber 30. The tow 10 advances around the mandrel 60, which forms a longitudinally extending channel in the forming rod of the tow.

Rotation of the mandrel 60 as the tow 10 passes through the forming chamber 30 creates a longitudinally extending channel whose cross-section varies longitudinally as it rotates about the central longitudinal axis of the channel.

The reciprocating motion of the mandrel 60 forms alternating first and second sections in the rod of filter material. The first section comprises a longitudinally extending core of filter material including a core-defining outer surface and a channel-defining inner surface, as described with respect to Figures 1-12. The second section comprises a longitudinally extending core of filter material that is continuous and homogenous and does not include channels.

The tow 10 is hardened in the forming chamber 30 by steam.

After the rod of filter material exits the forming chamber 30, it is treated with a high velocity air stream by the air jet element 40 to further harden the rod of filter material 50. The rod of filter material is then cut by the cutter 90 into individual filter elements, mouthpieces, or cooling elements.

The process and apparatus for forming the rods of filter material, forming the channels, and forming the alternating first and second sections will now be described in more detail with reference to Figures 14a and 14b.

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

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 filter material, such as the 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 so that the stuffer jet 20 is tapered. The fast moving air enters the stuffer jet 20 via the air inlet 22 and advances the tow longitudinally into and through the stuffer jet 20, where it is condensed into a cylindrical shape. After the tow exits the stuffer jet via the outlet 26, the tow 10 expands into a gap 25 between the outlet 26 of the stuffer jet and an inlet of a forming chamber that is spaced longitudinally from the outlet 26 of the stuffer jet 20. The expanded tow continues to advance longitudinally into the forming chamber 30. The forming chamber includes an inlet through which the expanded tow enters and an outlet through which the longitudinally extending rod 50 of filter material exits the forming chamber 30. The forming chamber 30 includes a steam inlet 32 through which steam enters the forming chamber. As shown in FIG. 13a, the forming chamber includes a curing zone 35 that extends along the longitudinal length of the forming chamber and across the width of the forming chamber 30. A mandrel 60 extends longitudinally through the center of the stuffer jet 20, the tow expansion element 25, and along the entire length of the curing zone 35 within the forming chamber 30, such that the ends of the mandrel 60 are aligned with the ends of the curing zone 35.

In this first configuration, the tow 10 passes through the annular space between the mandrel 60 and the inner surface of the forming chamber 30, thereby forming a channel extending along the length of the curing zone 35. Steam is applied to the filter material in the forming chamber 30, thereby hardening the filter material by consolidating the filter material to form a first section comprising a longitudinally extending core of filter material having an outer surface defining the longitudinally extending core of the filter material and an inner surface defining a longitudinally extending channel.

Figure 14b shows the mandrel 60 in a second position where the mandrel 60 is positioned behind the mandrel shown in Figure 14a. In the second position, the end of the mandrel 60 is longitudinally moved away from the first position assumed by the mandrel as shown in Figure 14a, and the mandrel 60 does not extend along the entire length of the curing zone 35. As shown in Figure 14b, the mandrel 60 is withdrawn outside the curing zone 35. In the second position, the tow 10 enters the space defined by the end of the mandrel 60 and the inner surface of the forming chamber 30 to form a second section comprising a longitudinally extending core of filter material without channels.

As shown in FIG. 14b, the first section advances forward and retains its shape, including the channel, due to steam applied to the filter material in the curing zone 35. Thus, the method forms alternating first and second sections. It will be appreciated that the filter material is advanced at a speed that correlates with the speed at which the mandrel reciprocates such that alternating first and second sections are formed. The relative speed of the advancing filter material and the mandrel can be controlled by a controller (not shown).

The shape of the mandrel determines the cross-sectional shape of the channels. For example, the rod used to make the mouthpiece, filter element or cooling element shown in Figures 1-6 is a cylinder containing two diametrically opposed grooves running along the length of the mandrel. The mandrel used to make the mouthpiece, filter element or cooling element shown in Figure 7 is a cylinder with two pairs of diametrically opposed grooves. The mandrel used to make the mouthpiece, filter element or cooling element shown in Figures 8 and 9 has a rectangular cross-section, and the mandrel used to form the mouthpiece, filter element or cooling element shown in Figures 10 and 11 has a cross-shaped cross-section.

The channel shape is defined by the mandrel as described above. At all times during the method, the mandrel is rotating. Rotation of the mandrel as the filter material passes through the forming chamber forms longitudinally extending channels, the channel cross section being varied longitudinally by rotation around the central longitudinal axis of the channel. In the case of grooved mandrels such as those used to make the mouthpieces, filter elements, or cooling elements shown in Figures 1-6, the grooves in the mandrel define ridges on the inner surface of the core that defines the channel. Rotation of the mandrel, and therefore rotation of the grooves, forms ridges on the inner surface of the core that defines the channel. The ridges extend along the inner surface and follow a helical path around the longitudinal axis of the channel. By controlling the speed of rotation of the mandrel and the speed at which the tow is drawn through the forming chamber, it is possible to vary the helical pitch of the ridges. The depth and width of each ridge may be altered by varying the depth and width of each groove in the mandrel. If additional ridges are desired, the mandrel may include additional grooves. For example, the mouthpiece, filter element, or cooling element shown in FIG. 7 utilizes a mandrel with four grooves.

The diameter of the channel at its widest point can be varied by changing the diameter of the rod at its widest point. Similarly, the diameter and shape of the core of the filter material can be varied by changing the diameter and shape of the molding chamber.

Applicant has found that the inclusion of a tow expansion element may improve channel definition by allowing the expanded tow to twist before entering the forming chamber, aiding in the formation of the channel as described above.

It will be appreciated that while the mandrel extends through the stuffer jet and tow blooming sections, channel formation may be initiated in these sections, but since no heating is applied, the filter material does not harden. This means that when the mandrel is withdrawn to a second position, a second section may still be formed that does not include channels.

The cutting steps are timed according to the type of filter element, mouthpiece, or cooling element desired. For example, the cutting steps can be timed to form a filter element, mouthpiece, or cooling element including a first section and a section as shown in FIG. 1. The rod of filter material can be cut through the center of each first section, thereby forming a filter element, mouthpiece, or cooling element having first, second, and third sections, the first and third sections being shorter than the second section. The rod can be cut such that each filter element, mouthpiece, or cooling element includes a first section, a second section, and a third section of the same length.

Claims (38)

A mouthpiece, filter element or cooling element for an aerosol-generating article, comprising: a first section having a longitudinally extending core of filter material having an outer surface and an inner surface, the inner surface defining a channel extending longitudinally from an end of the first section; and a second section having a longitudinally extending core of filter material, the first section and the second section being adjacent and integral, the channel having a non-circular cross-section that varies longitudinally by rotation about the longitudinal axis of the first section. The mouthpiece, filter element, or cooling element of claim 1, wherein the channel has a cross section that is a modified circle, a cross, or a rectangle with one or more protruding portions extending toward the center of the circle. A mouthpiece, filter element, or cooling element according to claim 1 or 2, wherein the inner surface comprises one or more ridges that extend helically around the longitudinal axis of the first section. A mouthpiece, filter element or cooling element according to any one of claims 1 to 3, comprising a third section comprising a longitudinally extending core of filter 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 mouthpiece, filter element, or cooling element of claim 4, wherein the channels of the third section have a non-circular cross-section that varies in the longitudinal direction by rotation about the longitudinal axis of the third section. The mouthpiece, filter element, or cooling element of claim 5, wherein the channel of the third section has a cross section that is a modified circle, a cross, or a rectangle with one or more protruding portions extending toward a center of the circle. A mouthpiece, filter element or cooling element for an aerosol-generating article, comprising: a first section comprising a longitudinally extending core of filter material having an outer surface and an inner surface, the inner surface defining a longitudinally extending channel from an end of the first section; and a second section comprising a longitudinally extending core of filter material, the inner surface comprising one or more ridges extending helically about the longitudinal axis of the first section, the first section and the second section being adjacent and integral. 8. The mouthpiece, filter element, or cooling element of claim 7, further comprising a third section comprising a longitudinally extending core of filter 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 mouthpiece, filter element, or cooling element of claim 8, wherein the inner surface comprises one or more ridges that extend helically about the longitudinal axis of the third section. The mouthpiece, filter element or cooling element of any one of claims 4, 5, 6, 8 or 9, wherein the third section is adjacent to and integral with the second section such that the second section is between the first section and the third section. A mouthpiece, filter element or cooling element according to any one of claims 3 to 10, wherein the or each ridge extends along the entire length of the inner surface. A mouthpiece, filter element, or cooling element according to any one of claims 3 to 11, wherein the inner surface has two or more ridges. The mouthpiece, filter element or cooling element according to claims 1 to 12, wherein the filter material contains a plasticizer. A filter for an aerosol-generating article, comprising a filter element according to any one of claims 1 to 13. A multiple rod comprising a plurality of mouthpieces, filter elements or cooling elements according to any one of claims 1 to 13 joined end-to-end in a mirror image relationship. An aerosol-generating article comprising a mouthpiece, a filter element or a cooling element according to any one of claims 1 to 13, or a filter according to claim 14. The aerosol-generating article according to claim 16, wherein the aerosol-generating article is a smoking article, the smoking article comprises a mouthpiece or filter element according to any one of claims 1 to 13, or a filter according to claim 14, and the mouthpiece, filter element or filter is joined to a rod of smokable material. 1. An apparatus for making a mouthpiece, filter element, or cooling element for an aerosol-generating article, comprising:
a forming chamber having an inlet for receiving a filter material and an outlet for discharging a rod of filter material; and a forming rod;
The forming rod is configured to rotate;
the molding chamber comprising a cure zone extending longitudinally along at least a portion of the length of the molding chamber;
the shaped rod is configured to move longitudinally between a first position in which an end of the shaped rod is positioned at an end of the curing zone and the shaped rod extends along the entire length of the curing zone, and a second position in which the end of the shaped rod is longitudinally spaced from the first position and the shaped rod does not extend along the entire length of the curing zone.
Device. The apparatus of claim 18, wherein the forming rod is coupled to a first motor for rotating the forming rod. 20. The apparatus of claim 18 or 19, wherein the forming rod is coupled to a second motor for moving the forming rod between the first position and the second position. The apparatus of any one of claims 18 to 20, wherein the forming chamber comprises a hollow, substantially cylindrical element for forming the filter material. The apparatus of any one of claims 18 to 21, wherein the shaped rod has a non-circular cross-section. 23. The device of claim 22, wherein the non-circular cross section is a modified circle, a cross, or a rectangle having one or more indentations. The apparatus of any one of claims 18 to 23, comprising a heating element for applying heat to the filter material. The apparatus of any one of claims 18 to 24, comprising a steam element for applying steam to the filter material. 26. The apparatus of claim 25, wherein the forming chamber includes a steam element for applying steam to the filter material in the curing zone. The apparatus of any one of claims 18 to 26, comprising a cutting element for cutting the rod of filter material. The apparatus of any one of claims 18 to 27, comprising a plasticizing element for applying a plasticizer to the filter material before it enters the forming chamber. 1. A method of making a mouthpiece, filter element, or cooling element for an aerosol-generating article, comprising the steps of:
longitudinally advancing the filter material;
drawing the filter material into and through a forming chamber;
the forming chamber having an inlet for receiving a filter material and an outlet through which a rod of filter material exits the forming chamber;
the molding chamber comprising a cure zone extending longitudinally along at least a portion of the length of the chamber;
moving the shaped rod longitudinally between a first position in which an end of the shaped rod is positioned at an end of the curing zone and the shaped rod extends along the entire length of the curing zone and a second position in which the end of the shaped rod is longitudinally spaced from the first position and the shaped rod does not extend along the entire length of the curing zone;
and rotating the forming rod;
at the first position, the advancing filter material advances through a space defined by an inner surface of the chamber and the forming rod to form a first section comprising a longitudinally extending core of filter material having an outer surface and an inner surface, the inner surface defining a longitudinally extending channel having a non-circular cross-section that varies longitudinally by rotation about a longitudinal axis of the first section;
at the second position, filter material advances into a space defined by the end of the shaped rod, the interior surface of the chamber, and the end of the cure zone to form a second section having a longitudinally extending core of filter material, thereby forming a longitudinally extending rod of filter material having alternating first and second sections.
Method. The method of claim 29, wherein heat is applied to the filter material in the curing zone. The method of claim 29 or 30, wherein steam is applied to the filter material in the curing zone. The method of any one of claims 29 to 31, wherein the forming chamber comprises a substantially cylindrical hollow element having an inlet for receiving filter material and an outlet for discharging a rod of filter material. The method of any one of claims 29 to 32, wherein the molded rod has a non-circular cross-section. The method of claim 33, wherein the non-circular cross-section is a modified circle, a cross, or a rectangle having one or more indentations. The method of any one of claims 29 to 34, comprising applying a plasticizer to the filter material before it is drawn into the forming chamber. The method of any one of claims 29 to 35, comprising expanding the filter material before it enters the forming chamber. The method of any one of claims 29 to 36, wherein the filter material is drawn into a stuffer jet before entering the forming chamber. The method of any one of claims 29 to 37, comprising cutting the longitudinally extending rod of filter material to form one or more filter elements, mouthpieces, or cooling elements.