Paper Filter

Abstract

A mouthpiece, filter or filter element comprising a longitudinally extending core of paper or other biodegradable (e.g., not containing cellulose acetate) filtration material, a first wrapper wrapped around a peripheral surface of the core, and a second wrapper wrapped around the first wrapper, the first wrapper together with at least the second wrapper defining a plurality of channels extending longitudinally from an upstream end of the mouthpiece, filter or filter element and / or a plurality of channels extending longitudinally from a downstream end of the mouthpiece, filter or filter element.

Description

[Technical field]

[0001] The present invention provides a mouthpiece, filter or filter element for use with a smoking article, such as a cigarette, a heated tobacco product, or a non-combustion heating product. [Background technology]

[0002] Mouthpieces, filters or filter elements for smoking articles such as cigarettes, heated tobacco products, or heat-not-burn (HNB) products can be manufactured from several different materials. Currently, 98% of commercially available cigarette filters contain cellulose acetate (source: Euromonitor International). However, cellulose acetate is not biodegradable, and as a result, cigarette filters (and cigarette butts) containing cellulose acetate can persist in the environment for years. For this reason, and in light of new EU legislation coming into force in 2021 (aimed at reducing the use of single-use plastics such as cellulose acetate filters), there is growing interest in filter elements (such as mouthpieces) that do not contain single-use plastics and are biodegradable.

[0003] An alternative filter material to cellulose acetate is paper. Filters that contain paper as a filter material are well known in the art. Paper filters offer many advantages over cellulose acetate filters in terms of improved biodegradability and higher filtration efficiency at a given pressure drop. However, paper filters also have many disadvantages, for example, paper filters can have a detrimental effect on the taste of cigarettes and have low retention of toxic phenolic compounds. Therefore, the smoking experience of cigarettes that use traditional paper (monopaper) filters is inferior to that of cigarettes with traditional cellulose acetate filters.

[0004] It is therefore desirable to provide a mouthpiece, filter or filter element for a smoking article (e.g., cigarettes, heated tobacco products, heat-not-burn (HNB) products) that offers acceptable filtration and sensory properties while having improved biodegradability compared to conventional materials such as cellulose acetate. Summary of the Invention

[0005] According to the present invention, in a first aspect, there is provided a mouthpiece, filter or filter element (e.g. for a smoking article such as a cigarette, a heated tobacco product, an HNB product, etc.) comprising a longitudinally extending core of paper or other biodegradable (e.g. non-cellulose acetate containing) filtration material, a first wrapper (e.g. plug wrap) wrapped around a peripheral surface of the core, and a second wrapper (e.g. plug wrap) wrapped around the first wrapper, wherein the first wrapper, together with at least the second wrapper, defines a plurality of channels extending longitudinally from an upstream end of the mouthpiece, filter or filter element and / or a plurality of channels extending longitudinally from a downstream end of the mouthpiece, filter or filter element.

[0006] According to the invention, in one aspect, there is provided a mouthpiece, filter or filter element (e.g., for a smoking article such as a cigarette, a heated tobacco product, an HNB product, etc.) comprising a longitudinally extending core of paper or other biodegradable (e.g., non-cellulose acetate containing) filtration material, a first wrapper (e.g., plug wrap) wrapped around a peripheral surface of the core, and a second wrapper (e.g., plug wrap) wrapped around the first wrapper, wherein the first wrapper, together with at least the second wrapper, defines a plurality of channels extending longitudinally of the mouthpiece, filter or filter element, but not extending from either the upstream or downstream ends of the mouthpiece, filter or filter element (e.g., extending only a portion of the length of the core).

[0007] The paper or other biodegradable (e.g., non-cellulose acetate) filtration material of the longitudinal core of the present invention is biodegradable and has enhanced biodegradability compared to cellulose acetate. Thus, the present invention provides a mouthpiece, filter or filter element that is enhanced in biodegradability and is therefore more environmentally friendly and more compliant with EU legislation.

[0008] The term "biodegradable" means that the paper or other biodegradable filtration material, mouthpiece, filter or filter element is capable of exhibiting at least 90% biodegradation after 6 months under controlled composting conditions (see ISO14855-1 Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions-Method by analysis of evolved carbon dioxide).

[0009] Preferably, the paper or other biodegradable filter material, mouthpiece, filter or filter element is "readily biodegradable". The term "readily biodegradable" refers to the fact that the paper or other biodegradable filter material, mouthpiece, filter or filter element can be rapidly degraded and completely biodegraded when immersed in water. Preferably, the paper or other biodegradable filter material, mouthpiece, filter or filter element has a "Ready Biodegradability" level of biodegradability measured according to the OECD 301B "Ready Biodegradability" method (modified Sturm test), which is well known in the art. The term "readily biodegradable" is understood herein to mean a "readily biodegradable" level of biodegradability.

[0010] In some instances, the channel may extend only a portion of the length of the core, while in other instances, the channel may extend the entire length of the core.

[0011] Where a channel may extend only part of the length of the core, it will be understood that the channel is closed or blocked at an end remote from the end of the mouthpiece, filter or filter element through which the channel extends. It will be further understood that where a channel extends the entire length of the core, the channel is open at both the upstream and downstream ends of the mouthpiece, filter or filter element.

[0012] At least one longitudinally extending portion of the mouthpiece, filter, or filter element may not include a channel within its cross section. It will be understood that the portion(s) may be located at either or both ends (i.e., the downstream end and / or the upstream end) of the mouthpiece, filter, or filter element, or the portion may be located in the center of the mouthpiece, filter, or filter element.

[0013] A portion (or each portion) of a mouthpiece, filter or filter element that does not contain a channel within its cross section is referred to herein as a rod or rod portion. A portion (or each portion) of a mouthpiece, filter or filter element that contains a longitudinally extending channel (extending the entire length of the core or only a portion of the length of the core) is referred to herein as a groove or grooved portion.

[0014] In one example, a mouthpiece, filter or filter element according to the invention comprises a 9 mm grooved portion at one end of the mouthpiece, filter or filter element and a 18 mm bar portion on the remaining length of the mouthpiece, filter or filter element (i.e., the other end of the mouthpiece, filter or filter element). In another example, a mouthpiece, filter or filter element according to the invention comprises a 7 mm grooved portion at the downstream end of the mouthpiece, filter or filter element, a 7 mm grooved portion at the upstream end of the mouthpiece, filter or filter element, and a 7 mm bar portion between the grooved portions. In another example, a mouthpiece, filter or filter element according to the invention is fully grooved and comprises a 27 mm grooved portion over the entire length of the mouthpiece, filter or filter element. In a further example, a mouthpiece, filter or filter element according to the invention comprises a 7 mm bar portion at the downstream end of the mouthpiece, filter or filter element, a 7 mm bar portion at the upstream end of the mouthpiece, filter or filter element, and a 7 mm grooved portion between the bar portions. Thus, a mouthpiece, filter or filter element according to the invention can have grooved portions and / or bar portions.

[0015] The length of the grooved portion(s) may be from 5 to 30 mm, such as from 8 to 25 mm, for example from 10 to 20 mm, such as from 12 to 15 mm. The length of the bar portion(s) may be from 5 to 30 mm, such as from 8 to 25 mm, for example from 10 to 20 mm, for example from 12 to 15 mm.

[0016] The applicants have found that a mouthpiece, filter or filter element with grooves or grooves and bars can provide improved filtration performance, especially with respect to phenol, compared to conventional paper (e.g., mono-paper) filters. Without being bound by theory, it is believed that the channels of the grooved portion(s) increase the surface area available for smoke filtration, thereby reducing the phenol yield compared to mono-paper filters. In one example, a mouthpiece, filter or filter element according to the present invention can reduce the phenol yield by up to 12% compared to mono-paper filters.

[0017] Furthermore, Applicants have found that in comparison to other mouthpieces, filters or filter elements that include grooves or grooves and bars, e.g., Corinthian™ filters, e.g., CPS™ filters, which are made from cellulose acetate combined with a plasticizer to create the grooves, the mouthpieces, filters or filter elements of the present invention do not contain plastic and are therefore biodegradable, yet still provide acceptable filtration and sensory properties.

[0018] Preferably, the length of the channels is between 5 mm and 30 mm, for example between 9 mm and 25 mm. The channels extending longitudinally from one end (upstream or downstream) may be of a different length than the channels extending from the other end, or may be the same length.

[0019] The channels are preferably of substantially uniform depth over the longitudinal extent of the channel, although there may be variation, for example if the channel extends only part of the length of the core and therefore has a closed end. The depth (e.g. maximum depth) of each channel is from 0.5mm to 2.6mm, such as from 0.8 to 2.2mm, for example from 1.3 to 2.1mm, preferably from 1.35 to 2mm, for example from 1.4 to 1.9mm.

[0020] The width (eg, maximum width) of each channel is from 1.0 to 3.0 mm, for example, from 1.3 to 2.1 mm, preferably from 1.35 to 2 mm, for example, from 1.4 to 1.9 mm.

[0021] The mouthpiece, filter or filter element may comprise 5 to 25 channels, preferably 10 to 16 channels, extending longitudinally from the upstream end of the mouthpiece, filter or filter element, and / or 5 to 25 channels, preferably 10 to 16 channels, extending longitudinally from the downstream end of the mouthpiece, filter or filter element.

[0022] The total cross-sectional area of ​​these channels may represent 2-12%, preferably 4-8%, of the overall cross-sectional area of ​​the mouthpiece, filter or filter element.

[0023] Applicants have found that mouthpieces, filters or filter elements with channels of these dimensions can provide improved mouthfeel compared to standard paper (e.g., monopaper) and standard cellulose acetate (e.g., monoacetate) filters. Without wishing to be bound by theory, it is believed that the additional ventilation provided by channels of these dimensions helps to overcome the "paper taste" typically associated with paper filters, reducing the harshness of the smoke or vapor, and thus improving mouthfeel.

[0024] The first wrapper may be a paper of 60 to 100 gsm basis weight, such as a paper of 70 to 90 gsm basis weight (e.g. plug wrap), for example a paper of 80 gsm basis weight (e.g. plug wrap). Preferably the first wrapper is air permeable.

[0025] The first wrapper may be colored. The first wrapper may be a colored paper (e.g., plug wrap). The color may be black, red, yellow, orange, green, blue, pink, purple, etc., or various shades thereof. As used herein, "colored" means a color (i.e., hue) that is different from white or off-white (i.e., the color of the paper).

[0026] Applicants have found that the use of a colored paper (e.g., plug wrap) carried by the first wrapper can provide a unique edge appearance that is visually appealing and can help combat counterfeiting.

[0027] The first wrapper may have longitudinally extending corrugations (e.g., grooves and ridges) that together with the second wrapper define longitudinally extending channels of the mouthpiece, filter or filter element. The first wrapper may be a sheet having a contoured surface, such as having longitudinally extending corrugations (e.g., grooves and ridges) along a regular portion of its length. The first wrapper may be wrapped around the peripheral surface of the core with the contoured (e.g., corrugated) surface facing the second wrapper. Each channel may be provided between the corrugations of the first wrapper and the inner surface of the second wrapper. A core of paper or other biodegradable (e.g., non-cellulose acetate-containing) filtration material may be conformed to the contoured (e.g., corrugated) surface of the first wrapper.

[0028] The first wrapper may have corrugated portions (i.e., longitudinally extending corrugations as described above) and non-contoured (i.e., flat) portions. The first wrapper may be a sheet with alternating contoured and flat surfaces, such as having longitudinally extending corrugations (e.g., grooves and ridges) along regular portions of its length and flat portions along regular portions of its length. As described above, the corrugated portions of the first wrapper may define, together with at least the second wrapper, longitudinally extending channels (i.e., grooved portions) of the mouthpiece, filter or filter element, but the flat portions of the first wrapper may not define channels (at least with the second wrapper) in the length of the core (i.e., rod portion) around which the flat portion of the first wrapper is wrapped. Thus, the corrugated and flat portions of the first wrapper may define, together with at least the second wrapper, the grooved and rod regions, respectively, of the mouthpiece, filter or filter element. It will be understood that a core of paper or other biodegradable (e.g., not containing cellulose acetate) filtration material may be conformed to a contoured (e.g., corrugated) and / or non-contoured (i.e., flat) surface of the first wrapper.

[0029] Applicants have found that using an 80 gsm paper wrapper having a contoured (e.g., corrugated) surface for the first wrapper maintains the structural integrity and depth of the channel.

[0030] The second wrapper may be a paper of from 25 to 140 gsm basis weight, such as a paper of from 60 to 100 gm basis weight (eg plug wrap), for example a paper of 80 gsm basis weight (eg plug wrap).

[0031] The second wrapper may be air permeable (e.g., up to 32000 Coresta units), or alternatively, the second wrapper may be air impermeable.

[0032] The mouthpiece or filter or filter element may include a plurality of additional channels defined by the first wrapper and at least the second wrapper, extending longitudinally of the core, extending only a portion of the length of the core, but not extending from either the upstream or downstream end of the core. The mouthpiece or filter or filter element may include 5 to 25 additional channels, preferably 10 to 16 additional channels, extending longitudinally of the core, extending only a portion of the length of the core, but not extending from either the upstream or downstream end of the core. In such an example, there are two or more sections of the filter (i.e., two or more rod sections) that have no channels.

[0033] In one example, a mouthpiece, filter or filter element according to the invention comprises a 5 mm groove portion at one end of the mouthpiece, filter or filter element, a 5 mm rod portion adjacent to the groove portion, a 5 mm groove portion at the other end of the mouthpiece, a 5 mm rod portion adjacent to the groove portion and a further 5 mm groove portion between the rod portions, such that the channels in this portion do not extend from either the upstream or downstream ends of the core.

[0034] The paper filtration material and / or other biodegradable (e.g., cellulose acetate-free) filtration material can be any form of paper conventionally used in filters for smoking articles. The paper filtration material and / or other biodegradable (e.g., cellulose acetate-free) filtration material can be standard paper, nonwoven paper, airlaid paper, carbon-impregnated paper, or cellulose / lyocell / viscose-based paper.

[0035] Paper filtration materials and / or other biodegradable (e.g., not containing cellulose acetate) filtration materials can be non-plastic plant-based fibers (e.g., flax, hemp, jute, sisal, abaca, coconut, bamboo, starch, or wood pulp or mixtures of these materials).

[0036] The applicants have found that the use of standard paper filtration material may be particularly suitable for the core of the present invention as it has good filtration properties and is flexible, allowing it to easily conform to the contoured (e.g. corrugated) and / or non-contoured (i.e. flat) surfaces of the first wrapper, meaning that the channels are only between the first and second wrappers.

[0037] Preferably, the length of the mouthpiece, filter or filter element is from 12 to 30 mm, such as from 15 to 28 mm, for example from 18 to 26 mm, for example from 20 to 24 mm.

[0038] Preferably, the circumference of the mouthpiece, filter or filter element is from 14 to 30 mm, such as from 16 to 25 mm, for example from 24 to 25 mm.

[0039] The mouthpiece or filter element may be biodegradable and may be greater than 90% biodegradable as measured according to ISO14855-1 Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions-Method by analysis of evolved carbon dioxide.

[0040] Preferably, the mouthpiece, filter or filter element has a "Ready Biodegradability" level of biodegradability as measured according to the OECD 301B "Ready Biodegradability" method (modified Sturm test).

[0041] The mouthpiece, filter or filter element may include a smoke or vapor modifier that may modify or enhance the consumer's experience. The smoke or vapor modifier may impart additional taste or aroma to the vapor passing through the mouthpiece or filter, or may suppress a particular flavor or aroma. The smoke or vapor modifier may be located in or on the longitudinally extending core of the paper or other biodegradable (e.g., not containing cellulose acetate) filtration material, or on the first and / or second wrapper. The smoke or vapor modifier may be a particulate additive. The particulate additive may be activated carbon (e.g., activated carbon granules), zeolite, ion exchange resin (e.g., weakly basic anion exchange resin), sepiolite (e.g., sepiolite granules), silica gel, alumina, molecular sieves, carbonaceous polymer resins, and diatomaceous earth. The particulate additive may be a mixture of two or more materials. The smoke or vapor modifier may be a liquid additive (e.g., a flavor enhancing additive, e.g., smoke chemical effects). The flavor enhancing additive may be any known in the art, e.g., menthol, peppermint, fruit, berry, vanilla, chocolate, coffee, etc., with a suitable carrier, e.g., propylene glycol, vegetable glycerin, medium-chain triglyceride (MCT) oil, other oils. The additive for smoke chemical effects may be PG, PEG, triacetin, or TEC.

[0042] The mouthpiece, filter or filter element of the present invention may be used in a multi-segment filter as a single segment with one or more separate additional segments. The filter structure could be two, three, four or more separate segments. The separate segments can be (e.g., cylindrical) plugs of filtering material (e.g., paper filtering material and / or other biodegradable (e.g., non-cellulose acetate-containing) filtering material), which can include, for example, capsules, carbon, CPS, tubes, acetate, paper, menthol, etc. The multi-segment filter can be attached to a tobacco rod (which can be made from any form of tobacco, including reconstituted).

[0043] In accordance with the present invention, there is provided a smoking article (e.g., a cigarette, e.g., a heated tobacco product, e.g., an HNB product) comprising a mouthpiece, filter, filter element or multi-segment filter as described herein and claimed below, joined at one end (e.g., by conventional means, i.e., by tipping paper) to a rolled tobacco rod.

[0044] In one example, a smoking article according to the invention comprises a filter according to the invention comprising a 9mm grooved portion at one end of the filter and a 18mm rod portion joined at the grooved end to a rolled tobacco rod (i.e. by tipping paper) for the remaining length of the filter. In another example, a smoking article according to the invention comprises a filter according to the invention comprising a 9mm grooved portion at one end of the filter and a 18mm rod portion joined at the rod end to a rolled tobacco rod (i.e. by tipping paper) for the remaining length of the filter.

[0045] In the above examples, it will be appreciated that the appearance of the end of a smoking article will appear different to a consumer depending on whether a grooved end or a rod end is joined to a wrapped tobacco rod, and therefore whether the grooved end or rod end is at the mouth end of the smoking article and therefore visible. Applicants have found that by locating a grooved portion (as opposed to a rod portion) at the mouth end of a smoking article, they can provide consumers with a unique end appearance that is visually appealing and may help resist counterfeiting.

[0046] Alternatively, placing the rod portion at the mouth end of the smoking article may give the impression of a standard single segment (ie, monopaper) filter.

[0047] According to the present invention, in another aspect, there is provided a method for making a mouthpiece, filter or filter element, the method comprising the steps of: providing a longitudinally extending continuous core of paper or other biodegradable (e.g., non-cellulose acetate containing) filtration material; wrapping and securing a first wrapper (e.g., plug wrap) around a peripheral surface of the core; wrapping and securing a second wrapper around the wound core, the first wrapper together with at least the second wrapper defining a plurality of channels extending longitudinally of the core; and cutting the continuous core to form individual mouthpieces or filter elements, the cut ends being configured to form an upstream end of the mouthpiece, filter or filter element and a downstream end of the mouthpiece, filter or filter element.

[0048] The first wrapper may be a sheet that has been embossed to provide a contoured surface, such as having longitudinally extending corrugations (e.g., grooves and ridges) along regular portions of its length.

[0049] Preferably, the first wrapper paper is uniformly embossed to provide grooves of uniform depth and width over their longitudinal extent. The depth of the grooves may be from 0.5mm to 2.6mm, such as from 0.8 to 2.2mm, for example from 1.3 to 2.1mm, preferably from 1.35 to 2mm, for example from 1.4 to 1.9mm. The width (e.g. maximum width) of each groove may be from 1.0 to 3.0mm, such as from 1.3 to 2.1mm, preferably from 1.35 to 2mm, for example from 1.4 to 1.9mm.

[0050] The first wrapper may have embossed (e.g., corrugated) and non-contoured (i.e., flat) portions. The embossed and flat portions may alternate and may be of the same or different lengths.

[0051] It will be appreciated that the corrugated portions of the first wrapper, together with at least the second wrapper, may define a channel (i.e., a grooved portion) extending longitudinally of the core, but the flat portion of the first wrapper may not define a channel (at least with the second wrapper) in the length of the core (i.e., the rod portion) around which the flat portion of the wrapper is wrapped. Thus, the corrugated and flat portions of the first wrapper, together with at least the second wrapper, may define the grooved and rod regions, respectively, of an individual mouthpiece, filter or filter element (i.e., after cutting).

[0052] A continuous core of paper or other biodegradable (e.g., not containing cellulose acetate) filtration material may be cut axially at any location along the continuous core to form individual mouthpieces or filter elements. It will be understood that the cut ends form the upstream end of the mouthpiece, filter or filter element and the downstream end of the mouthpiece, filter or filter element. Thus, depending on whether the continuous core is cut through or between the grooved or rod sections, the length and arrangement of the mouthpiece, filter or filter element (i.e., groove-rod, i.e., groove-rod-flume, i.e., groove, i.e., rod-groove-rod).

[0053] It will be understood that the above-described paper or other biodegradable (e.g., not containing cellulose acetate) filtration materials, first wrapper, second wrapper, channel dimensions, etc., can be used in the methods of making a mouthpiece, filter or filter element.

[0054] According to the present invention there is provided a mouthpiece, filter or filter element obtainable by the method described herein and claimed below. [Brief description of the drawings]

[0055] The invention will now be described in more detail with reference to the accompanying drawings. [Figure 1]FIG. 1 shows a perspective view of a mouthpiece, filter or filter element according to an example of the present invention. [Diagram 2] 1 shows a perspective view of a mouthpiece, filter or filter element according to another example of the present invention. [Diagram 3] 1 shows a perspective view of a mouthpiece, filter or filter element according to another example of the present invention. [Figure 4] 1 shows a perspective view of a mouthpiece, filter or filter element according to another example of the present invention. [Diagram 5] 1 shows a comparison of mainstream smoke delivery of a filter of the present invention with a conventional paper filter and a CPS acetate filter.

[0056] 1 shows a mouthpiece, filter or filter element 100 having a length of 27 mm and a circumference of 24 mm. The mouthpiece, filter or filter element 100 comprises a longitudinally extending core 101 of standard paper filtration material having a length of 27 mm, a first wrapper 102 of 80 gsm paper wrapped around the peripheral surface of the core 101, and a second wrapper 103 of 100 gsm paper wrapped around the first wrapper 102. The first wrapper 102 together with at least the second wrapper 103 define sixteen channels 104 having a depth of 1.5 mm, a width of 1.2 mm and a length of 9 mm, extending longitudinally from the upstream end (i.e., the grooved portion) of the mouthpiece, filter or filter element 101. The total cross-sectional area of ​​these channels is 6.1% of the overall cross-sectional area of ​​the mouthpiece, filter or filter element. The remaining 18 mm of the length of the mouthpiece, filter or filter element 100 does not include channels within its cross section (ie, the bar portion).

[0057] The mouthpiece, filter or filter element 100 comprises: providing a longitudinally extending continuous core of 36 gsm standard paper filtration material; wrapping and securing a first wrapper of 80 gsm paper around a peripheral surface of the core in alternating embossed (e.g., corrugated) and non-contoured (i.e., flat) sections; wrapping and securing a second wrapper of 100 gsm paper around the wound core, the first wrapper together with at least the second wrapper defining a plurality of channels extending longitudinally of the core; and cutting the continuous core between the embossed and non-contoured portions of the first wrapper to form individual mouthpieces, filters or filter elements 100, the cut ends of which are configured to form a fluted upstream end of the mouthpiece, filter or filter element and a rod downstream end of the mouthpiece, filter or filter element, using techniques well known in the art.

[0058] 2 shows a mouthpiece, filter or filter element 200 having a length of 27 mm and a circumference of 24 mm. The mouthpiece, filter or filter element 200 comprises a longitudinally extending core 201 of standard paper filtration material having a length of 27 mm, a first wrapper 202 of 80 gsm paper wrapped around the peripheral surface of the core 201, and a second wrapper 203 of 100 gsm paper wrapped around the first wrapper 202. The first wrapper 202 together with at least the second wrapper 203 define sixteen channels 204 having a depth of 1.2 mm, a width of 1.8 mm and a length of 27 mm that extend longitudinally along the entire length of the core 201. The total cross-sectional area of ​​these channels is 4.5% of the overall cross-sectional area of ​​the mouthpiece, filter or filter element.

[0059] It will be appreciated that the method of making the mouthpiece, filter or filter element 100 described above may be used to make the mouthpiece, filter or filter element 200. However, in the method for making the mouthpiece, filter or filter element 200, the first wrapper is only embossed to have longitudinally extending corrugations (e.g., grooves and ridges) along regular portions of its length and does not include any non-contoured (i.e. flat) portions.

[0060] 3 shows a mouthpiece, filter or filter element 300 having a length of 27 mm and a circumference of 24 mm. The mouthpiece, filter or filter element 300 comprises a longitudinally extending core 301 of standard paper filtration material having a length of 27 mm, a first wrapper 302 of 80 gsm paper wrapped around the peripheral surface of the core 301, and a second wrapper 303 of 100 gsm paper wrapped around the first wrapper 302. The first wrapper 302 together with at least the second wrapper 303 define 16 channels 304 having a depth of 1.35 mm, a width of 1.35 mm and a length of 9 mm extending longitudinally from the upstream end of the mouthpiece, filter or filter element 300, and 12 channels 304 having a depth of 1.35 mm, a width of 1.35 mm and a length of 9 mm extending longitudinally from the downstream end of the mouthpiece, filter or filter element 300. The total cross-sectional area of ​​these channels is 4.8% of the overall cross-sectional area of ​​the mouthpiece, filter or filter element. The remaining 9 mm of the length of the mouthpiece, filter or filter element 300 does not include any channels within its cross section (i.e., the bar portion).

[0061] It will be appreciated that the method of making mouthpiece, filter or filter element 100 described above may be used to make mouthpiece, filter or filter element 300. However, in the method for making mouthpiece, filter or filter element 300, a continuous core is cut through the embossed portion of the first wrapper, such that the cut edges form the grooved upstream and downstream edges of mouthpiece, filter or filter element 300.

[0062] 4 shows a mouthpiece, filter or filter element 400 having a length of 27 mm and a circumference of 24 mm. The mouthpiece, filter or filter element 400 comprises a longitudinally extending core 401 of standard paper filtration material having a length of 27 mm, a first wrapper 402 of 80 gsm paper wrapped around the peripheral surface of the core 401, and a second wrapper 403 of 100 gsm paper wrapped around the first wrapper 402. The first wrapper 402 together with at least the second wrapper 403 define sixteen channels 404 having a depth of 1.35 mm, a width of 1.35 mm and a length of 7 mm that do not extend from either the upstream or downstream ends of the mouthpiece, filter or filter element 400. The total cross-sectional area of ​​these channels is 4.8% of the overall cross-sectional area of ​​the mouthpiece, filter or filter element. The two remaining 7 mm lengths of mouthpiece, filter or filter element 400 on either side of the 7 mm grooved section do not contain channels within their cross sections (ie, the bar portions).

[0063] It will be appreciated that the method of making mouthpiece, filter or filter element 100 described above may be used to make mouthpiece, filter or filter element 400. However, in the method for making mouthpiece, filter or filter element 400, a continuous core is cut through the uncontoured (i.e., flat) portion of the first wrapper, such that the cut ends form the upstream and downstream ends of mouthpiece, filter or filter element 400.

[0064] It will be appreciated that the mouthpiece, filter or filter element 100, 200, 300 and 400 may be used in a multi-segment filter as a single segment with one or more separate further segments. It will further be appreciated that the mouthpiece, filter or filter element 100, 200, 300 and 400, or a multi-segment filter comprising 100, 200, 300 or 400, may be joined at one end to a rolled tobacco rod for use as a smoking article (e.g., a cigarette, e.g., a heated tobacco product, e.g., an HNB product).

[0065] Smoke and Sensory Experiment 1 Filter A of the present invention (as shown in Figure 1) was made by the method described above. The filter was tested against a conventional paper filter (i.e., monopaper) and a conventional cellulose acetate filter (i.e., monoacetate).

[0066] Filter A, the mono paper filter, and the mono acetate filter were assembled for smoke testing by joining each filter at one end to a rolled tobacco rod to form a cigarette. The mouth end of each cigarette was then inserted into a smoking machine configured to smoke the cigarette. The experiments were conducted at standard room temperature and humidity.

[0067] The amount of phenol in the smoke of cigarettes with filter A (30.8 mg / cigarette) is lower than the amount of phenol in the smoke of cigarettes with mono paper filters (34.7 mg / cigarette). Thus, the filter of the present invention can reduce the amount of phenol by up to 12% compared to the mono paper filter.

[0068] Filter A, the mono paper filter and the mono acetate filter were assembled for sensory testing by joining each filter at one end to a rolled tobacco rod to form a cigarette. Preliminary smoking panel results suggest that the mouthpiece, filter or filter element of the present invention may provide improved mouthfeel compared to the mono paper filter and the mono acetate filter.

[0069] Smoke and Sensory Experiment 2 Filter A of the present invention (as shown in Figure 1) was made by the method described above. The filter was tested against a cellulose acetate filter of the same construction having high quality crimped cellulose acetate fibers bonded together by a plasticizer (i.e., a Combined Performance Superior™ (CPS™) filter available from Essentra plc.). This filter is referred to as CPS acetate.

[0070] The Filter A and the CPS acetate filter were assembled for smoke testing by joining each filter at one end to a rolled tobacco rod to form a cigarette. The mouth end of each cigarette was then inserted into a smoking machine configured to smoke the cigarette. The experiments were conducted at standard room temperature and humidity.

[0071] Figure 5 shows the amount of phenol, nicotine free dry particulate matter (NFDPM), nicotine, carbon monoxide and water in the smoke of each filter cigarette. For comparison, the results of the mono paper filter cigarette from Smoke and Sensory Experiment 1 are included in Figure 5.

[0072] Filter A has a lower nicotine-free dry particulate matter (NFDPM) yield (11.4 mg / cigarette) than the CPS acetate filter (13.69 mg / cigarette). Thus, the filter of the present invention can reduce the amount of NFDPM compared to the CPS acetate filter. Filter A also has nicotine, carbon monoxide and water yields comparable to the CPS filter, indicating that the mouthpiece, filter or filter element of the present invention is comparable to a cellulose acetate filter of the same structure. Thus, the mouthpiece, filter or filter element of the present invention can provide a biodegradable alternative to the CPS acetate filter with comparable filtration properties.

[0073] Filter A and CPS acetate filters were assembled for sensory testing by joining each filter at one end to a rolled tobacco rod to form a cigarette. The smoking panel results suggest that the mouthpiece, filter or filter element of the present invention improves mouthfeel compared to the monopaper and CPS acetate filters. In the experiment, Filter A provided a smoother smoke than the monopaper filter, and both provided a smoother smoke than the CPS acetate.

[0074] Biodegradability Experiment The biodegradability of paper filtration materials and / or other biodegradable (e.g., non-cellulose acetate containing) filtration materials used in the mouthpieces, filters or filter elements of the present invention was compared to the biodegradability of known cellulose acetate filters and filters containing cellulose acetate.

[0075] Biodegradability was measured according to ISO14855-1 Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions-Method by analysis of evolved carbon dioxide. This test provides a measure of the biodegradability of a material (expressed as a percentage) over a period of 180 days under optimal oxygen, temperature and humidity conditions.

[0076] Table 1 shows the biodegradability results for monoacetate filters, airlaid paper filters (Genia), wood pulp paper filters and hemp paper filters compared to conventional cellulose acetate (CA) filter rods when tested according to the method of ISO 14855-1. Filters were either purchased or made according to methods known in the art.

[0077] [Table 1]

[0078] Table 1 shows that wood pulp paper and hemp paper have the highest biodegradability among all filtration materials. Furthermore, airlaid paper (Genia) also shows good biodegradability compared to CA.

[0079] Thus, the paper filtration materials and / or other biodegradable filter materials used in the mouthpieces or filter elements of the present invention degrade faster and more extensively than cellulose acetate.

Claims

1. 1. A mouthpiece, filter or filter element comprising: a longitudinally extending core of paper or other biodegradable, cellulose acetate-free filtration material; a first wrapper wrapped around the peripheral surface of the core; and a second wrapper wrapped around the first wrapper, wherein the first wrapper, together with at least the second wrapper, defines a plurality of channels extending longitudinally from an upstream end of the mouthpiece, filter or filter element and / or a plurality of channels extending longitudinally from a downstream end of the mouthpiece, filter or filter element, the channels extending along only a portion of the length of the core.

2. 1. A mouthpiece, filter or filter element comprising: a longitudinally extending core of paper or other biodegradable, cellulose acetate-free filtration material; a first wrapper wrapped around the peripheral surface of the core; and a second wrapper wrapped around the first wrapper, the first wrapper, together with at least the second wrapper, defining a plurality of longitudinally extending channels of the mouthpiece, filter or filter element, the plurality of channels extending only a portion of the length of the core and not extending beyond either the upstream or downstream ends of the mouthpiece, filter or filter element.

3. 10. The mouthpiece, filter or filter element of claim 1, wherein the channel extends the entire length of the core.

4. A mouthpiece, filter or filter element according to claim 1 or 2, wherein at least one longitudinally extending portion of the mouthpiece, filter or filter element does not include a channel in its cross-section, and / or the length of the channels is between 5 mm and 30 mm, for example between 9 mm and 25 mm, and / or the depth of each channel is between 0.5 mm and 2.6 mm, for example between 0.8 mm and 2.2 mm, such as between 1.3 mm and 2.1 mm, preferably between 1.35 mm and 2 mm, for example between 1.4 mm and 1.9 mm, and / or the width of each channel is between 1.0 mm and 3.0 mm, for example between 1.3 mm and 2.1 mm, preferably between 1.35 mm and 2 mm, for example between 1.4 mm and 1.9 mm.

5. 3. The mouthpiece, filter or filter element of claim 1 or 2, comprising 5 to 25 channels, preferably 10 to 16 channels, extending longitudinally from the upstream end of the mouthpiece, filter or filter element, and / or 5 to 25 channels, preferably 10 to 16 channels, extending longitudinally from the downstream end of the mouthpiece, filter or filter element, and / or wherein the total cross-sectional area of ​​the channels extending longitudinally from the upstream and / or downstream ends of the mouthpiece, filter or filter element is 2 to 12%, preferably 4 to 8%, of the overall cross-sectional area of ​​the mouthpiece, filter or filter element.

6. 3. The mouthpiece, filter or filter element according to claim 1 or 2, wherein the first wrapper is a paper with a basis weight of 60 to 100 gsm, such as a paper with a basis weight of 70 to 90 gsm, for example a paper with a basis weight of 80 gsm.

7. 3. The mouthpiece, filter or filter element of claim 1 or 2, wherein the first wrapper is air permeable, and / or the first wrapper has longitudinally extending corrugations which, together with the second wrapper, define the channels extending longitudinally of the filter, and / or the second wrapper is a paper having a basis weight of 25 to 140 gsm, for example a paper having a basis weight of 70 to 90 gsm, for example a paper having a basis weight of 80 gsm.

8. 3. The mouthpiece, filter or filter element of claim 1 or 2, further comprising a plurality of further channels defined by the first wrapper and at least the second wrapper, the further channels extending longitudinally of the core and extending only a portion of the length of the core, but not extending from either the upstream or downstream end of the core; and / or wherein the paper filtration material and / or other biodegradable, cellulose acetate-free filtration material is standard paper, nonwoven paper, airlaid paper, carbon-impregnated paper, or a cellulose / lyocell / viscose-based paper.

9. A mouthpiece, filter or filter element as claimed in claim 1 or 2, wherein the paper filtering material and / or other biodegradable, cellulose acetate-free filtering material is a non-plastic plant fibre, such as flax, hemp, jute, sisal, abaca, coconut, bamboo, starch or wood pulp, or a mixture of these materials, and / or the length of the mouthpiece, filter or filter element is 12 to 30 mm, such as 15 to 28 mm, for example 18 to 26 mm, for example 20 to 24 mm.

10. the mouthpiece or filter element is more than 90% biodegradable when measured according to ISO 14855-1 Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions - Method by analysis of evolved carbon dioxide, and / or the mouthpiece, filter or filter element is more than 90% biodegradable when measured according to OECD 301B "Ready to compost" method.

3. The mouthpiece, filter or filter element according to claim 1 or 2, having a "Ready Biodegradability" level of biodegradability as measured according to the "Ready Biodegradability" method (modified Sturm test).

11. A multi-segment filter comprising a mouthpiece, filter or filter element according to claim 1 or 2 and one or more separate further segments.

12. A smoking article comprising a mouthpiece, filter, or filter element according to claim 1 or 2 joined at one end to a wound tobacco rod.

13. A method for making a mouthpiece, filter, or filter element, comprising the steps of providing a longitudinally extending continuous core of paper or other biodegradable, cellulose acetate-free filtering material; wrapping and securing a first wrapper around a peripheral surface of the continuous core; wrapping and securing a second wrapper around the wound continuous core, the first wrapper together with at least the second wrapper defining a plurality of channels extending longitudinally of the continuous core; and cutting the continuous core to form individual mouthpieces or filter elements, the cut ends configured to form an upstream end of the mouthpiece, filter or filter element and a downstream end of the mouthpiece, filter or filter element.

14. 14. A method of making a mouthpiece, filter or filter element according to claim 13, wherein the first wrapper is embossed to provide a contoured (e.g. corrugated) surface, such as having longitudinally extending corrugations along regular portions of its length.

15. A mouthpiece, filter or filter element obtainable by the method of claim 13.

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