Method for manufacturing a filter element or a mouthpiece

Abstract

A method of manufacturing a filter element or mouthpiece (300) is disclosed, comprising the steps of longitudinally advancing filter material and drawing the advancing filter material into a forming element (110) to form a longitudinally extending rod of filter material with channels extending longitudinally through the rod of filter material, wherein the forming element (110) comprises a chamber and a forming rod (200) extending longitudinally within the chamber, an inner surface of the chamber shaping the advancing filter material to form the longitudinally extending rod of filter material, the shaping rod (200) shaping the advancing filter material to form channels extending longitudinally through the rod of filter material, and the shaping element (110) applies an additive to the filter material.

Description

Technical Field

[0001] The present invention relates to a mouthpiece, a filter element, and a filter, as well as methods for manufacturing these, and an apparatus used for manufacturing the filter element or the mouthpiece.

Background Art

[0002] Tube filter elements and tube mouthpieces for smoking articles are known in the art. Typically, a tube filter element or mouthpiece includes a cylindrical core of filter material having a channel extending longitudinally from an end of the cylindrical core. Tube filter elements are often included as part of a multi-segment filter, and the tube filter element is typically disposed at the mouth end of the filter to provide a unique end appearance that can serve an anti-counterfeiting purpose.

[0003] It is known in the art that additives such as flavorants are present in tobacco smoke filters. Typically, it is difficult to introduce flavorants into the filter material and difficult to retain flavorants in the filter material, so flavorants are not directly incorporated into the tube filter element. Tube filter elements often form part of a multi-segment filter where further filter elements perform further filtration or contain additives such as flavorants.

[0004] Applying an additive such as a flavorant after the filter element is formed can cause problems of contamination arising from the wet filter. Further, applying the flavorant in this way can potentially cause unacceptable odors and affect the air quality near the manufacturing line.

[0005] Accordingly, there is a need for tube filter elements or mouthpieces that contain additives such as flavorants so as not to require additional filter elements to provide additives to the tube filter or mouthpiece.

Summary of the Invention

Means for Solving the Problems

[0006] In one aspect of the present invention, there is provided a method of making a filter element or a mouthpiece, including the steps of advancing a filter material in a longitudinal direction, and drawing the advancing filter material into a forming element, thereby forming a longitudinally extending rod of the filter material that includes a channel extending longitudinally through the rod of the filter material, wherein the forming element includes a chamber and a forming rod (mandrel) extending longitudinally within the chamber, an inner surface of the chamber shaping the advancing filter material to form a longitudinally extending rod of the filter material, the forming rod shaping the advancing filter material to form a channel extending longitudinally through the rod of the filter material, and the forming element applying an additive to the filter material.

[0007] The applicant has discovered that by the method of the present invention, it is possible to directly apply an additive to a filter material that forms a filter element or a mouthpiece. The applicant has discovered that after the filter element or the mouthpiece is manufactured, most of the additive applied to the filter material remains as it is. The applicant has discovered that a filter element or a mouthpiece manufactured according to the method of the present invention exhibits an excellent additive filling amount and shows an additive level that is maintained for a long time even after the manufacture of the filter element / mouthpiece. This means that it is possible to provide a tube filter or a mouthpiece that does not require an additional filter element, for example, to impart flavor to the smoke generated by a smoking article. Further, by applying the additive within the forming element, the additive is more likely to fit within a small space, thus not affecting the air quality around the filter / mouthpiece manufacturing apparatus and not causing concern about the odor associated with the additive.

[0008] The forming rod may also be referred to as a mandrel.

[0009] The filter material can be a continuously advancing filter material.

[0010] Preferably, the additive is applied by a forming rod.

[0011] The forming rod can comprise a cavity and a plurality of apertures coupled to the cavity, such that when the advancing filter material passes through the forming element, the additive moves from the cavity and is discharged from the forming rod through the plurality of apertures. The plurality of apertures can be a plurality of holes or slits. Preferably, the plurality of apertures can be a plurality of holes. The forming rod can include 4 to 24 holes, such as 8 to 24 holes, such as 12 to 24 holes, such as 16 to 24 holes, such as 20 to 24 holes, such as 24 holes. The holes can be equally spaced around the circumference of the forming rod. The forming rod can include 1, 2, 3 or 4 sets of 6 holes equally spaced around the forming rod.

[0012] The forming rod can comprise an outer surface that defines the shape of a channel that longitudinally penetrates the rod of the filter material. The inner surface of the forming element chamber shapes the filter material as the filter material passes through the forming element, thereby defining the shape (e.g., cylindrical) of a longitudinally extending rod. The advancing filter material surrounds the forming rod as it advances through the forming element chamber. The filter material is pushed between the inner surface of the chamber and the outer surface of the forming rod. Thereby, the forming rod forms a longitudinally extending channel inside the longitudinally extending rod of the filter material.

[0013] The plurality of apertures (e.g., holes) can be disposed on the outer surface of the forming rod.

[0014] The cavity can be a channel defined by the inner surface of the forming rod. The channel is connected to the plurality of holes such that the additive can move from the channel and be discharged from the forming rod through the plurality of holes located on the outer surface of the forming rod.

[0015] The forming rod can have, for example, a substantially circular cross-section, an elliptical cross-section, a triangular cross-section, a three-leaf cross-section, or a star-shaped cross-section. It will be understood that the shape of the forming rod determines the shape of the channels formed in the rod of filter material. Thus, for example, a forming rod having a circular cross-section will produce channels having a circular cross-section.

[0016] The forming rod can have a diameter of 0.5 mm to 10 mm, for example 1 mm to 8 mm, for example 1 mm to 4 mm, for example 4 mm to 8 mm, for example 3 mm to 6 mm. It will be understood that the diameter of the forming rod determines the diameter of the channels.

[0017] The inner surface of the chamber can define a substantially cylindrical hollow shape. The inner surface of the chamber defines the outer shape of the rod extending in the longitudinal direction of the filter material and thus will define the overall shape of the finished mouthpiece or filter element. For example, the inner surface of the chamber defining a cylinder will form a rod of filter material that is substantially cylindrical.

[0018] The inner surface of the chamber can have a circumference of 14 mm to 27 mm. It will be understood that the inner circumference of the chamber can define the outer circumference of the rod extending in the longitudinal direction of the filter material.

[0019] The filter material can be drawn from a source before being advanced towards the forming element.

[0020] Preferably, a plasticizer is applied to the advancing filter material.

[0021] The plasticizer can be applied to the advancing filter material before the advancing filter material is drawn into the forming element. For example, the plasticizer can be applied to the filter material at a plasticizing station before the filter material enters the forming element. The plasticizer can be sprayed onto the filter material, for example, onto the outer surface of the filter material. Alternatively, the plasticizer may be applied to the filter material in advance via a separate process in which the plasticizer is separated. The plasticizer can be triacetin, triethylene glycol diacetate (TEGDA) or polyethylene glycol (PEG).

[0022] The plasticizer can be applied in an amount such that the filter material contains 8% to 24% by weight of the filter material and the plasticizer, for example, about 12% to 24% by weight of the filter material and the plasticizer, for example, about 14% to 22% by weight, for example, about 16% to 20% by weight, for example, about 17% to 19% by weight, for example, about 18% by weight.

[0023] The amount of plasticizer present in the filter material is calculated by the following general formula as a percentage of the total weight of the filter material and the plasticizer.

[0024] Percentage % of plasticizer = Quantity of plasticizer (g) × 100 / (Quantity of plasticizer (g) + Quantity of filter material (g))

[0025] The addition of the plasticizer to the filter material can cure the filter material, thereby improving the shape definition of the filter element or the mouthpiece, particularly the shape definition of the channels.

[0026] Preferably, when the advancing filter material passes through the forming element, steam is applied to the advancing filter material. The steam may be applied directly to the filter material advancing within the forming element. The steam may be superheated steam. The forming element can include a steam inlet to allow steam (e.g., superheated steam) to move into the forming element and come into direct contact with the filter material when the filter material is formed. The steam has the effect of curing the filter material when the filter material is formed. The steam can be applied directly to the outer surface of a rod extending in the longitudinal direction of the filter material when the filter material is formed within the forming element.

[0027] Preferably, the additive is a liquid. The additive may form a spray when discharged from a plurality of apertures. For example, the additive may be pumped under pressure through an aperture from a cavity or channel so that the additive is discharged from the forming rod as a spray. As used herein, the term "spray" means a dynamic collection of droplets dispersed in a gas.

[0028] Surprisingly, Applicants have found that high additive loadings, e.g., flavorant loadings, can be achieved in the final product despite applying the additive in the presence of steam. Without wishing to be bound by theory, it is hypothesized that the additive is less susceptible to loss by evaporation because the additive is applied within the filter material and the forming element that confines the additive. Further, by applying the additive when forming the filter material, it is hypothesized that the additive can penetrate the filter material and coat individual fibers in the case of a fibrous filter material.

[0029] Preferably, the additive is a smoke or aerosol modifier, such as a smoke modifier. The smoke or aerosol modifier may contain a flavoring agent. Examples of suitable flavoring agents include menthol, spearmint, clove, nutmeg, cinnamon, lemon, chocolate, peach, strawberry, vanilla, etc. The flavoring agent may be a liquid composition containing only the flavoring agent, or the liquid composition may further contain a liquid carrier such as an alcohol, e.g., propylene glycol, or another organic solvent.

[0030] When the additive is a flavoring agent, the flavoring agent is applied such that the final filter element or mouthpiece has a flavoring agent loading of from 1 mg per filter element / mouthpiece to 30 mg per filter element / mouthpiece, e.g., from 2 mg per filter element / mouthpiece to 25 mg per filter element / mouthpiece, e.g., from 2 mg per filter element / mouthpiece to 20 mg per filter element / mouthpiece, e.g., from 2 mg per filter element / mouthpiece to 10 mg per filter element / mouthpiece, e.g., from 2 mg per filter element / mouthpiece to 8 mg per filter element / mouthpiece, e.g., from 4 mg per filter element / mouthpiece to 8 mg per filter element / mouthpiece, e.g., 6 mg per filter element / mouthpiece.

[0031] The filter material can be any of the materials conventionally used in the manufacture of tobacco smoke filters (usually filamentous, fibrous, web-like, or extruded). The filter material can be, for example, natural or synthetic filament tow of cotton or plastics such as polyethylene or polypropylene, or cellulose acetate filament tow. The filter material can be a thermoplastic or otherwise spinnable polymer, such as polypropylene, polyethylene terephthalate, or polylactide. The filter material can be, for example, natural or synthetic staple fibers, absorbent cotton, web materials such as paper (usually crepe-like), and synthetic non-woven materials, as well as extruded materials (such as starch foams, synthetic foams). Preferably, the filter material includes cellulose acetate filament tow.

[0032] Optionally, the filter material may contain a binder material. Optionally, the filter material may contain a water-soluble binder material. Examples of water-soluble binder materials include water-soluble polymer materials such as polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl ether, starch, polyethylene glycol, and polypropylene glycol; blends of plasticizers such as triacetin, triethylene glycol diacetate (TEGDA), or polyethylene glycol (PEG) with water-soluble binders; and particulate hot melt water-soluble binders. By including a water-soluble binder material, for example, the ability to easily and rapidly decompose filter elements or mouthpieces formed by the process of the present invention under environmental conditions can be further improved.

[0033] When the filter material is filament tow, this can be drawn from two sources, for example, two bales of filament tow. The tow can be drawn from each bale and subsequently spread laterally before applying a plasticizer to the surface of the tow fibers. Spreading the tow laterally increases the surface area available for applying the plasticizer.

[0034] After the plasticizer is applied, the corn can be collected before entering the forming element.

[0035] This method may further include the step of cooling the rod extending in the longitudinal direction of the filter material after it is discharged from the forming element. The cooling can be carried out by one or more jets of air directed at the rod extending in the longitudinal direction of the filter material.

[0036] This method may further include the step of wrapping the rod extending in the longitudinal direction of the filter material with a paper material such as a plug wrap. The rod extending in the longitudinal direction of the filter material may be wrapped after the cooling step.

[0037] This method may further include the step of cutting the rod extending in the longitudinal direction of the filter material to form a filter element or a mouthpiece. The rod extending in the longitudinal direction of the filter material can be cut using standard cutting methods known in the art such as a rotary drum cutter. The cutting step may be performed after cooling the rod extending in the longitudinal direction of the filter material.

[0038] In a further aspect of the invention, a filter element or a mouthpiece formed by the method according to any of the above descriptions is provided.

[0039] In a further aspect of the invention, there is provided a forming rod for use in a method of making a filter element or a mouthpiece, comprising a longitudinal rod including a cavity and an outer surface, and a plurality of apertures located on the outer surface of the longitudinal rod, the plurality of apertures being coupled to the cavity.

[0040] The cavity may be in the form of a channel defined by the inner surface of the forming rod, such as a cylindrical channel.

[0041] The plurality of apertures can extend from the outer surface of the forming rod to the cavity or channel.

[0042] The plurality of apertures can include a plurality of holes or slits, preferably a plurality of holes.

[0043] The forming rod can include 4 to 24 holes, such as 8 to 24 holes, such as 12 to 24 holes, such as 16 to 24 holes, such as 20 to 24 holes, such as 24 holes. The holes can be arranged equidistantly around the circumference of the forming rod. The forming rod can include one, two, three or four sets of six holes arranged equidistantly around the forming rod.

[0044] The forming rod can be made of a metal such as brass or stainless steel. The forming rod can have, for example, a circular cross-section, an elliptical cross-section, a triangular cross-section, a three-leaf cross-section, or a star-shaped cross-section. It will be understood that the shape of the forming rod determines the shape of the channels formed in the rod of the filter material. Thus, for example, a forming rod having a circular cross-section produces channels having a circular cross-section.

[0045] In a further aspect of the invention, there is provided an apparatus for making a filter element or a mouthpiece, the apparatus comprising a forming element comprising a chamber and a forming rod according to the invention, the forming rod extending longitudinally within the chamber.

[0046] The chamber can have an inner surface configured to shape the filter material so as to thereby form a rod extending longitudinally of the filter material. The forming rod can be configured to shape the filter material so as to form channels extending longitudinally through the rod of the filter material. The chamber and the forming rod together can be configured to form a longitudinal rod of filter material including channels extending longitudinally therethrough. The forming rod may be configured to apply an additive, such as a flavorant, to the filter material within the chamber. The forming rod may be configured to apply the additive in the form of a spray. The chamber may comprise an inner surface defining a hollow cylinder.

[0047] The chamber can include one or more steam inlets configured to allow steam, such as superheated steam, to enter the chamber. A particular steam inlet or each steam inlet can be configured to apply steam or superheated steam to the filter material within the chamber, for example, directly. A particular steam inlet or each steam inlet can be configured to apply steam or superheated steam directly to the outer surface of a rod extending in the longitudinal direction of the filter material when formed within the forming element.

[0048] The forming rod can be aligned centrally within the chamber. Aligning the forming rod centrally means that the channels formed in the rod extending in the longitudinal direction of the filter material are disposed centrally within the rod extending in the longitudinal direction of the filter material.

[0049] The forming rod can be connected to an additive reservoir. The apparatus can further include a pump for pumping the additive from the additive reservoir to the forming rod.

[0050] The apparatus can further include one or more of a plasticizing station configured to apply a plasticizer to the filter material or for applying a plasticizer to the filter material, and a cutting element configured to cut a rod extending in the longitudinal direction of the filter material or for cutting a rod extending in the longitudinal direction of the filter material.

[0051] The apparatus can further include a wrapping element configured to wrap a rod extending in the longitudinal direction of the filter material before cutting or for wrapping a rod extending in the longitudinal direction of the filter material.

[0052] In a further aspect of the present invention, there is provided a filter element or a mouthpiece comprising a core extending in the longitudinal direction of the filter material, the core having an outer surface and an inner surface; a channel extending from an end of the core, the channel being defined by the inner surface of the core; and a layer of additive disposed on the inner surface of the core.

[0053] The core extending in the longitudinal direction of the filter material can have a substantially circular or elliptical cross-section. Preferably, the core extending in the longitudinal direction has a substantially circular cross-section, for example, a circular cross-section. It will be understood that a substantially circular cross-section results in a substantially cylindrical core.

[0054] The channel can extend through a part of the length of the core extending in the longitudinal direction or through the entire length of the core extending in the longitudinal direction.

[0055] The channel can have a substantially circular cross-section, an elliptical cross-section, a triangular cross-section, a three-lobed cross-section, or a star-shaped cross-section.

[0056] The filter material can be any of the materials conventionally used in the manufacture of cigarette filters (usually filamentous, fibrous, web-like, or extruded). The filter material can be, for example, natural or synthetic filament tow of cotton or plastics such as polyethylene and polypropylene, or cellulose acetate filament tow. The filter material can also be a thermoplastic or spinnable polymer, such as polypropylene, polyethylene terephthalate, or polyactide. The filter material can be, for example, natural or synthetic staple fibers, absorbent cotton, web materials such as paper (usually crepe-like), and synthetic non-woven materials, as well as extruded materials (e.g., starch foam, synthetic foam). Preferably, the filter material includes cellulose acetate filament tow.

[0057] The filter material may optionally include a binder material. The filter material may optionally include a water-soluble binder material. Examples of water-soluble binder materials include water-soluble polymer materials such as polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl ether, starch, polyethylene glycol, and polypropylene glycol; blends of plasticizers such as triacetin, triethylene glycol diacetate (TEGDA), or polyethylene glycol (PEG) with water-soluble binders; and particulate hot melt water-soluble binders. By including a water-soluble binder material, for example, the ability of a filter element or mouthpiece formed by the method of the present invention to decompose easily and rapidly under environmental conditions can be further improved.

[0058] The total denier of the filter material can be about 12,000 to 100,000 g per 9000 m, for example 20,000 to 80,000 g per 9000 m, for example 20,000 to 50,000 g per 9000 m.

[0059] In the case of a filter material formed from a single tow of yarn, the total denier of the filter material can be about 12,000 to 50,000 g per 9000 m, for example 30,000 g to 40,000 g per 9000 m, for example 30,000 g to 38,000 g per 9000 m, for example 30,000 g, 32,000 g, 33,000 g, 37,000 g, or 40,000 g per 9000 m.

[0060] In the case of a filter material formed from two tows of yarn, the total denier of the filter material can be about 20,000 to 100,000 g per 9000 m, for example 60,000 g to 80,000 g per 9000 m, for example 60,000 g to 76,000 g per 9000 m, for example 60,000 g, 64,000 g, 66,000 g, 74,000 g, or 80,000 g per 9000 m.

[0061] The filament denier can be 1.5 g to 12 g per 9000 m, for example 1.5 g to 9 g per 9000 m, for example 5 g, 7.3 g, 8 g or 9.0 g per 9000 m.

[0062] The filter material is usually described with reference to the filament denier, the total denier, and the fiber cross-section. For example, the filter material can include tows having a denier of 8.0Y40, 8.0Y32, 7.3Y33, or 9.0Y37. For example, a filter material with a denier of 8.0Y40 means that the filament denier is 8.0 g per 9000 m, the total denier is 40000 g per 9000 m, and the filament has a Y-shaped cross-section.

[0063] The filter material may contain a plasticizer. The filter material can contain the plasticizer in an amount of about 8 wt% to 24 wt% of the filter material and the plasticizer, for example, about 12 wt% to 24 wt% of the filter material and the plasticizer, for example about 14 wt% to 22 wt%, for example about 16 wt% to 20 wt%, for example about 17 wt% to 19 wt%, for example about 18 wt%.

[0064] The amount of plasticizer present in the mouthpiece or the filter element is calculated as a percentage of the total weight of the filter material and the plasticizer via the general formula shown below.

[0065] Percentage of plasticizer % = Quantity of plasticizer (g) × 100 / (Quantity of plasticizer (g) + Quantity of filter material (g))

[0066] The plasticizer functions to harden the filter material. By hardening the filter material, the shape definition of the filter element, particularly the definition of channels, can be improved. For example, the filter material can include plasticized fibers, such as plasticized tow, such as plasticized cellulose acetate tow. The plasticizer can be, for example, triacetin, triethylene glycol diacetate (TEGDA) or polyethylene glycol (PEG). The plasticizer can be applied to the filter material by spraying it onto the surface of the filter material using methods known in the art.

[0067] The layer of additive may include a smoke modifier such as a flavorant. Examples of suitable flavorants include menthol, spearmint, clove, nutmeg, cinnamon, lemon, chocolate, peach, strawberry, vanilla, etc.

[0068] When the additive is a flavorant (e.g., menthol), the filter element or mouthpiece can have a flavorant loading of from 1 mg per filter element / mouthpiece to 30 mg per filter element / mouthpiece, for example, from 2 mg per filter element / mouthpiece to 25 mg per filter element / mouthpiece, for example, from 2 mg per filter element / mouthpiece to 20 mg per filter element / mouthpiece, for example, from 2 mg per filter element / mouthpiece to 10 mg per filter element / mouthpiece, for example, from 2 mg per filter element / mouthpiece to 8 mg per filter element / mouthpiece, for example, from 4 mg per filter element / mouthpiece to 8 mg per filter element / mouthpiece, for example, 6 mg of flavorant loading per filter element / mouthpiece. The additive may also be dispersed within a core extending in the longitudinal direction of the filter material, for example, throughout the core extending in the longitudinal direction of the filter material.

[0069] The outer perimeter of the mouthpiece or filter element can be from 14 mm to 27 mm. The channel can have a diameter of, for example, from 0.5 mm to 10 mm, such as from 1 mm to 8 mm, such as from 1 mm to 4 mm, such as from 4 mm to 8 mm, such as from 3 mm to 6 mm.

[0070] The length of the mouthpiece or filter element can be from 4.0 mm to 50 mm, such as from 5.0 mm to 40 mm, such as from 10 mm to 35 mm, such as from 18.0 mm to 30 mm, such as from 22 mm to 28 mm, such as about 25 mm.

[0071] The core extending in the longitudinal direction of the filter material can be wrapped with a wrapper or plug wrap, such as a paper wrapper, such as an air-permeable paper wrapper.

[0072] The mouthpiece or filter element can be for use as part of a tobacco smoke filter or as a filter for smokable materials other than tobacco such as marijuana or cannabis.

[0073] The mouthpiece or filter element of the present invention can be incorporated into smoking articles such as cigarettes, cigars, and cigars. The mouthpiece or filter element of the present invention can be incorporated into tobacco heating products or electronic cigarettes. The mouthpiece or filter element can also be used alone or as part of a filter that the user assembles to form a smoking article (e.g., a roll-your-own smoking article).

[0074] In a further aspect of the present invention, there is provided a filter containing a filter element according to the present invention, such as a tobacco smoke filter.

[0075] The filter can include an outer wrapper, such as a plug wrap, that encloses the filter element. The wrapper can be paper, such as air-permeable paper. The wrapper can have a weight of 20 to 100 grams per square meter, such as 20 to 50 grams per square meter, such as 27 to 35 grams per square meter.

[0076] In a further aspect of the invention, there is provided a smoking article comprising the filter, filter element or mouthpiece as described above. The smoking article can include the filter as described above, coupled to a rod of smoking material, such as a tobacco smoking material. Generally, in the case of a smoking article comprising a marijuana or cannabis smoking material, the smoking article includes a mouthpiece according to any of the above descriptions. The smoking article can further include a tipping wrapper, such as tipping paper. The tipping wrapper joins the rod of smoking material to the filter or mouthpiece by engaging around an adjacent end of the filter or mouthpiece and the rod of smoking material. The tipping wrapper can be configured to leave a portion of the outer surface of the filter / mouthpiece or filter wrapper exposed. The filter can be joined to the rod of smoking material by a full tipping wrapper that engages around the entire length of the filter or mouthpiece and the adjacent end of the rod of smoking material.

[0077] The mouthpiece, filter element, filter or smoking article according to the present invention may not be ventilated, or may be ventilated by methods well known in the art, for example, by using a pre-perforated or breathable filter wrapper (plug wrap) or tipping wrapper (tipping paper), and / or by using laser perforation of the filter wrapper and / or tipping wrapper. The mouthpiece, filter, filter element or smoking article according to the present invention can be ventilated by laser perforation of a core extending in the longitudinal direction of the filter material (as well as the wrapper (plug wrap) and tipping wrapper (tipping paper) if present). A fully breathable tipping wrapper (tipping paper) can also be inherently breathable or provided with ventilation holes. In a ventilated product where both a filter wrapper (plug wrap) and a tipping wrapper (tipping paper) are present, the ventilation through the tipping wrapper (tipping paper) typically coincides with the ventilation through the filter wrapper (plug wrap). Ventilation holes passing through the filter wrapper (plug wrap), or the tipping wrapper (tipping paper), or both simultaneously can be created by laser perforation during the manufacture of the mouthpiece, filter, or filter element.

[0078] 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 in an end-to-end mirror relationship.

[0079] Next, preferred embodiments of the present invention will be described by way of example only with reference to the accompanying drawings.

Brief Description of the Drawings

[0080]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0081] FIG. 1 shows a schematic view of a method for manufacturing a filter element or a mouthpiece according to the present invention.

[0082] The filament tow 100 is simultaneously drawn from two bales of tow 102a and 102b and continuously advances in the longitudinal direction L. Each advancing web of tows 100a and 100b is bloomed by a blooming device 104 that spreads the fibers in the transverse direction. Next, each web of the laterally spread fibers enters a plasticizing station 106, where a plasticizer is sprayed onto each web of the advancing laterally spread fiber tow to form two webs of plasticized filament tow. The plasticizer is sprayed onto the surface of the fibers constituting the filament tow. Although the plasticizer is triacetin, it will be understood that other plasticizers may also be suitable. The two webs of plasticized filament tow are collected in a collecting device 108 to form a single web of plasticized filament tow. The web of plasticized filament tow continues to advance in the longitudinal direction and enters a forming element 110. The forming element 110 forms the tow into a longitudinally extending rod of filter material through which a longitudinally extending channel passes.

[0083] The forming element includes a hollow cylindrical chamber (die) formed of a metallic material such as brass or stainless steel, through which the plasticized tow advances. The chamber has an inner surface that defines a hollow cylinder extending in the longitudinal direction L. The inner surface can have a circumference of 14 mm to 27 mm. As the tow advances into the chamber, the tow is formed against the inner surface of the chamber to form a cylindrical rod extending in the longitudinal direction of the filter material.

[0084] The forming element 110 also includes a mandrel shown in FIGS. 2 and 3. The mandrel extends in the longitudinal direction L within the center of the chamber.

[0085] As shown in FIG. 2, the forming rod (mandrel) 200 includes a frustoconical section 202 from which a cylindrical rod 204 extends. The cylindrical rod 204 has an outer surface 206 and a cavity (not shown). The portion of the cylindrical rod located near the free end of the cylindrical rod 204 includes a plurality of holes 208 (e.g., 4 sets of 6 equally spaced holes) that extend into the cavity through the outer surface 206. The plurality of holes are regularly spaced over the entire circumference of the outer surface of the mandrel. The mandrel can be made from any suitable metal such as brass or stainless steel.

[0086] Returning to FIG. 1, when the web of plasticized tow advances into the forming element 110, the plasticized tow is pressed against the outer surface of the cylindrical rod 204. Thereby, the cylindrical rod 204 forms a cylindrical channel within the rod extending in the longitudinal direction of the filter material. That the cylindrical rod 204 is cylindrical means that a substantially cylindrical channel is formed within the rod of the filter material. It will be understood that other shaped rods 204 are possible, such as rods having a triangular, elliptical or star-shaped cross-section. The cross-sectional shape and diameter of the rod 204 determine the cross-sectional shape and diameter of the channel formed within the rod extending in the longitudinal direction of the filter material. The cylindrical rod 204 can have a diameter of 0.5 mm to 10 mm, such as 1 mm to 8 mm, such as 1 mm to 4 mm, such as 4 mm to 8 mm, such as 3 mm to 6 mm.

[0087] The mandrel 200 can be aligned centrally within the chamber of the forming element 110. Aligning the mandrel 200 centrally means that the channel formed within the rod extending in the longitudinal direction is disposed centrally within the rod of the filter material extending in the longitudinal direction.

[0088] The mandrel 200 can include two or more cylindrical rods 204, for example, two, three, or four cylindrical rods, thereby forming a plurality of channels in the rod of the filter material. In such a configuration, the mandrel can include two, three, or four pins protruding in the longitudinal direction, thereby forming two, three, or four channels in the filter material.

[0089] The mandrel 200 further applies an additive in the form of a menthol composition to the continuously advancing filter material. The additive is pumped from an external reservoir 112 and conveyed to the mandrel by a pipe 114. The pipe 114 is connected to the frustoconical section 202 of the mandrel 200. The additive passes through the cavity in the mandrel and is discharged from the mandrel through a plurality of holes 208. When the additive is discharged from the holes 208, the additive forms a spray. The spray of the additive is directed towards the filter material and the additive penetrates throughout the filter material. The additive can also form a layer on the inner surface of the filter material that defines the channels.

[0090] As described above, the plurality of holes extend over the entire circumference of the cylindrical rod 204, which means that the additive can be applied in many directions, thereby applying the additive throughout the filter material.

[0091] The menthol composition includes a solvent such as menthol and propylene glycol. It should be understood that the menthol composition can also include pure menthol without a solvent.

[0092] Superheated steam is applied directly to the filter material within the forming element chamber via a steam inlet pipe that passes outside the forming element. The superheated steam functions to cure the plasticized filter material when the plasticized filter material is formed by the forming element. The curing cures the filter material such that the rod shape and channel shape of the filter material are clearly defined. The superheated steam is applied directly to the outer surface of the rod extending in the longitudinal direction of the filter material when the rod extending in the longitudinal direction of the filter material is formed by the forming element chamber.

[0093] Surprisingly, the applicant has found that despite the presence of steam within the forming element, a high menthol loading can be achieved and, as shown in Examples 1 and 2, the menthol remains incorporated into the filter material over a long period of time.

[0094] After the rod extending in the longitudinal direction of the filter material is discharged from the forming element, the rod continues to advance, is cooled by the air jet 116, and is cut by the rotary cutter 118 to form a filter element or a mouthpiece.

[0095] Before being cut, the rod extending in the longitudinal direction of the filter material may be wrapped with a paper wrapper.

[0096] The filter element or mouthpiece may be incorporated into a multiple rod including a plurality of filter elements or mouthpieces joined in an end-to-end mirror image relationship.

[0097] The filter element or mouthpiece can be incorporated into a smoking article using techniques well known in the art.

[0098] Figure 3 is a perspective view of a filter element or mouthpiece according to the present invention.

[0099] The filter element or mouthpiece 300 shown in FIG. 3 can be manufactured by the method described above.

[0100] The filter element or mouthpiece 300 includes a core 302 extending in the longitudinal direction of the filter material. The longitudinally extending core 302 has an outer surface 304 and an inner surface 306. The filter material includes cellulose acetate filament tow and a plasticizer such as triacetin. The filter element or mouthpiece also includes a channel 308 extending from the end of the core, and the channel is defined by the inner surface of the core. The channel includes a layer of menthol disposed on the inner surface of the core. The core 302 also includes menthol dispersed throughout the filter material. The filter element or mouthpiece contains approximately 6 mg of menthol per filter element / mouthpiece.

[0101] The filter element or mouthpiece 300 can form part of a smoke filter suitable for a tobacco smoking article or a smokable material other than tobacco such as marijuana or cannabis. Further, the filter element or mouthpiece can be used in a heated or electronic tobacco type device.

Example

[0102] The filter element was made according to the method described above and shown in FIG. 1.

[0103] The filter element includes a core extending in the longitudinal direction of cellulose acetate filament tow having an inner surface and an outer surface, and a cylindrical channel extending from the end of the filter element is defined by the inner surface. The core was formed from two bales of cellulose acetate tow having a denier of 5.0 Y30.

[0104] The filter material included menthol applied according to the method of the present invention. Menthol was applied as a liquid solution containing menthol and propylene glycol. The filter material included triacetin in an amount of 19.7% of the total weight of the filter material and the plasticizer, and this was applied according to the method of the present invention. The cylindrical channel had a diameter of 5 mm. The length of the filter element was 120 mm.

[0105] The filter elements were analyzed in 10 batches. Each batch included 4,520 filter elements. From each batch, 5 multi-segment filters each having 6 filter elements were assembled. The 5 multi-segment filters from each batch were analyzed using gas chromatography, and the menthol filling amount was measured over 32 days. The average menthol filling amount was calculated based on the measured values of each batch at each time point. Further, using a quality tester (QTM3 (laser gauge) Cerulean), the filter circumferences of 10 multi-segment filters from each batch were measured. The results are shown in Table 1 below.

[0106]

Table 1

[0107] As shown in Table 1, the tested filters had a highly desirable menthol filling amount exceeding the target filling amount of 2.52 on the first day. The menthol filling amount remained substantially constant until the 32nd day, and no significant decrease in the menthol filling amount was observed.

[0108] The circumference also remained constant from the first day to the 32nd day, and no significant increase in the circumference was observed.

Example

[0109] The filter elements were created according to the method described above and shown in FIG. 1.

[0110] The filter element includes a core extending in the longitudinal direction of a cellulose acetate filament tow having an inner surface and an outer surface, and a star channel extending from the end of the filter element is defined by the inner surface. The core was formed from two bales of cellulose acetate tow having a denier of 5.0Y30.

[0111] The filter material included menthol applied according to the method of the present invention. The menthol was applied as a liquid solution containing menthol and propylene glycol. The filter material included 19.7% by weight of triacetin, based on the total weight of the filter material and the plasticizer, as a plasticizer, and this was applied according to the method of the present invention. The cylindrical channel had a diameter of 5 mm. The length of the filter element was 120 mm.

[0112] The filter elements were analyzed in batches of 10. Each batch included 4520 filter elements. From each batch, five multi-segment filters each having six filter elements were assembled. The five multi-segment filters from each batch were analyzed using gas chromatography, and the menthol filling amount was measured over 32 days. The average menthol filling amount was calculated based on the measured values of each batch at each time point. Further, using a quality tester (QTM3 (laser gauge) Cerulean), the filter circumferences of 10 filter elements from each batch were measured. The results are shown in Table 2 below.

[0113]

Table 2

[0114] As shown in Table 2, the tested filters had a highly desirable menthol filling amount on the first day. The menthol filling amount remained substantially constant until the 33rd day, and no significant decrease in the menthol filling amount was observed.

[0115] The circumference also remained constant from the first day to the 33rd day, and no significant increase in the circumference was observed.

Claims

1. A method for manufacturing a filter element or a mouthpiece (300), comprising: Advancing a filter material (100a, 100b) in a longitudinal direction; Drawing the advancing filter material (100a, 100b) into a forming element (110), thereby forming a longitudinally extending rod of the filter material that includes a channel passing longitudinally through the rod of the filter material; including: The forming element (110) includes a chamber and a forming rod (200) extending longitudinally within the chamber; An inner surface of the chamber forms the advancing filter material (100a, 100b) to form the longitudinally extending rod of the filter material; The forming rod (200) forms the advancing filter material (100a, 100b) to form a channel passing longitudinally through the rod of the filter material; The forming element (110) applies a flavoring agent to the filter material; Directly applying steam to the advancing filter material as the advancing filter material passes through the forming element.

2. The method according to claim 1, wherein the forming rod (200) applies the flavoring agent to the filter material.

3. The forming rod (200) includes a cavity and a plurality of holes (208) connected to the cavity. When the advancing filter material (100a, 100b) passes through the forming element (110), the flavoring agent moves from the cavity and is discharged from the forming rod (200) through the plurality of holes (208). The method according to claim 1 or 2.

4. The method according to any one of claims 1 to 3, wherein the forming rod (200) includes an outer surface (206) defining a shape of the channel passing longitudinally through the rod of the filter material.

5. The method according to claim 3 or 4, wherein the flavoring agent is a liquid.

6. The method according to claim 5, wherein a spray is formed when the flavoring agent is discharged from the plurality of holes (208).

7. The method according to any one of claims 1 to 6, wherein a plasticizer is applied to the advancing filter material (100a, 100b).

8. The method according to claim 7, wherein the plasticizer is applied to the filter material before the filter material is drawn into the forming element (110).

9. The method according to any one of claims 1 to 8, wherein when the rod extending in the longitudinal direction of the filter material is formed within the forming element (110), the vapor is directly applied to the outer surface of the rod extending in the longitudinal direction of the filter material.

10. The method according to any one of claims 1 to 9, further comprising the step of cutting the rod extending in the longitudinal direction of the filter material to form a filter element or a mouthpiece (300).

11. The method according to any one of claims 1 to 10, wherein the flavorant is applied to the filter material in the presence of vapor.

12. An apparatus for producing a filter element or a mouthpiece (300), comprising a forming element (110) including a chamber and a forming rod (200) for use in a method of manufacturing a filter element or a mouthpiece (300), wherein the forming rod (200) includes a longitudinal rod (204) including a cavity and an outer surface (206), and at least 24 holes (208) disposed on the outer surface (206) of the longitudinal rod (204), the at least 24 holes (208) extending from the outer surface (206) to the cavity and being connected to the cavity. wherein the forming rod (200) extends longitudinally within the chamber, the chamber comprises one or more vapor inlets, the one or more vapor inlets being configured to directly apply vapor to filter material (100a, 100b) within the chamber, and the apparatus is configured such that, in use, the forming rod (200) applies a flavorant to filter material (100a, 100b) within the chamber.

Images