Sustainable filters and filter elements

Abstract

The present invention provides a filter (1) for use in an aerosol-generating article, the filter comprising: a first longitudinally extending core (3) comprising a first filtering material; a second longitudinally extending core (7) comprising a second filtering material, the second longitudinally extending core having a pressure drop of 0.1 to 1 mmWG per mm of its length; and a wrapper (11) engaged around the first and second longitudinally extending cores, wherein each of the first and second filtering materials comprises paper and / or other biodegradable material, and the second longitudinally extending core is formed from paper and / or other biodegradable material, the paper and / or other biodegradable material being gathered laterally into a rod form and held in place.

Description

[Technical Field]

[0001] The present invention provides sustainable filters and filter elements for use with aerosol-generating articles such as tobacco heating products, heat-not-burn (HNB) products or heated tobacco products (HTP). [Background technology]

[0002] Tobacco heating products (heat-not-burn (HNB) products or heated tobacco products (HTP)) are well known. The concept of a tobacco heating product is that tobacco is heated to a specific temperature (e.g., 350°C) without combustion. This is thought to deliver a nicotine-containing vapor, and heating without combustion avoids the production of combustion products that are harmful to the consumer.

[0003] Tobacco heating products (HNB products or HTPs) may contain an improved tobacco plug and other mouthpiece elements wrapped in a paper plugwrap to provide a cigarette-like appearance. In one such product, a reconstituted tobacco plug, a wrapped hollow acetate tube, a PLA (poly(lactic acid)) wrapped plug, and a conventionally wrapped acetate segment (at the mouth end) are all wrapped in white paper. In use, the product is inserted tobacco-end first into a device containing a heating element in the form of a heating blade, which enters the tobacco plug as the product is forced into the device. The heating blade heats the tobacco, allowing the product to be "smoked" by a consumer who draws on the mouth end of the product. The function of the "filter" in these products is very different from that of a cigarette filter, the primary function of which is to provide the appearance and feel of a cigarette and also to cool the vapor to a temperature acceptable to the consumer. In the above-described products, it is the PLA portion that performs the key cooling function and, therefore, may be considered the cooling element.

[0004] The use of materials such as PLA in cooling elements is well known, and more recently, the use of cellulose acetate in cooling elements has become known, as discussed in WO 2021 / 074222.

[0005] However, cellulose acetate and PLA are not readily biodegradable. As a result, aerosol-generating article components such as cellulose acetate, including filter and cooling components, can persist in the environment for many years. For this reason, and in light of new EU legislation coming into effect in 2021 (aimed at reducing the use of single-use plastics such as cellulose acetate filters), there is growing interest in filters that are free of single-use plastics and readily biodegradable.

[0006] Therefore, there is a need for a filter that provides acceptable cooling and filtering properties of vapors in HNB products or HTPs while having improved biodegradability compared to conventional materials such as cellulose acetate. Summary of the Invention

[0007] According to the present invention, in a first aspect, there is provided a (e.g., biodegradable, e.g., readily biodegradable) filter for use in an aerosol-generating article (e.g., a tobacco heating product and / or an HNB product or HTP), the filter comprising a first longitudinally extending (e.g., cylindrical) core comprising a first filtering material, and a second longitudinally extending (e.g., cylindrical) core comprising a second filtering material (e.g., paper, e.g., uncoated paper, coated paper, siliconized paper), wherein the second a second longitudinally extending core having a pressure drop of 0.1 to 1 mmWG per mm of length, e.g., 0.31 to 0.7 mmWG per mm of length, e.g., 0.5 to 0.6 mmWG per mm of length, and wrappers (e.g., filter wrappers) engaged around the first and second longitudinally extending cores, each of the first and second filtering materials comprising paper and / or other biodegradable material (e.g., non-cellulose acetate containing material). The second longitudinally extending core has a pressure drop of 0.1 to 1 mmWG per mm of length, e.g., 0.31 to 0.7 mmWG per mm of length, e.g., 0.5 to 0.6 mmWG per mm of length, e.g., 0.53 to 0.57 mmWG per mm of length, e.g., 0.55 mmWG per mm of length. Preferably, the second longitudinally extending core has a pressure drop of 0.5 to 0.6 mmWG per mm of its length, such as a pressure drop of 0.53 to 0.57 mmWG per mm of its length, such as a pressure drop of 0.55 mmWG per mm of its length. In some examples of the invention, the first longitudinally extending core is longitudinally spaced from the second longitudinally extending core such that the wrapper defines a cavity between the first longitudinally extending core and the second longitudinally extending core.

[0008] The second longitudinally extending core has a cooling effect (eg, on the core, the second longitudinally extending core and / or the aerosol drawn through the filter).

[0009] The first longitudinally extending core may be formed from paper (e.g., uncoated paper, coated paper, siliconized paper, e.g., Puracel FM26, Puracel FM36, and / or Greenbutts) and / or other biodegradable material, which is laterally gathered into a rod form and held in place (e.g., by a wrapper, e.g., a first core wrapper). The first longitudinally extending core may be formed from paper (e.g., uncoated paper, coated paper, siliconized paper, e.g., Puracel FM26, Puracel FM36, and / or Greenbutts) and / or other biodegradable material having a width of 20 mm to 350 mm, such as 200 mm to 350 mm, for example 250 to 350 mm, for example 251 to 350 mm, for example 280 to 320 mm, for example 300 mm, which is laterally gathered into a rod form and held in place (e.g., by a wrapper, e.g., a first core wrapper). It will be appreciated that the first longitudinally extending core may have a wrapper (e.g., a first core wrapper) that holds the filtering material in an appropriate shape (e.g., in core form, e.g., in rod form or plug form). This wrapper (e.g., the first core wrapper) is separate from the wrappers (e.g., the filter wrappers) engaged around the first and second longitudinally extending cores, for example. It will be understood that if a wrapper (e.g., the first core wrapper) for the first longitudinally extending core is present, the wrappers (e.g., the filter wrappers) engaged around the first and second longitudinally extending cores are wrapped around the wrapper of the first longitudinally extending core (e.g., the first core wrapper) as well as the first longitudinally extending core itself.

[0010] The second longitudinally extending core may be formed from paper (e.g. uncoated paper, coated paper, siliconized paper, e.g. ZNP paper) and / or other biodegradable material, which is laterally gathered into a rod form and held in place (e.g. by a wrapper, e.g. second core wrapper). The second longitudinally extending core may be formed from paper (e.g. uncoated paper, coated paper, siliconized paper, e.g. ZNP paper) and / or other biodegradable material, which is laterally gathered into a rod form and held in place (e.g. by a wrapper, e.g. second core wrapper), having a width of 20 mm to 350 mm, such as 200 mm to 350 mm, for example 250 to 350 mm, such as 251 to 350 mm, for example 280 to 320 mm, for example 300 mm. As mentioned above, the second longitudinally extending core preferably has a pressure drop of 0.5 to 0.6 mmWG per mm of length, such as a pressure drop of 0.53 to 0.57 mmWG per mm of length, for example a pressure drop of 0.55 mmWG per mm of length. A second longitudinally extending core having a pressure drop of 0.5 to 0.6 mmWG per mm of length and formed from paper with a width of 300 mm may have a density of 0.269 g / cm. 3 Preferably, the density of the second longitudinally extending core is 0.215 g / cm 3 ~0.33g / cm 3 , e.g., 0.22 g / cm 3 ~0.31g / cm 3 , e.g., 0.24 g / cm 3 ~0.30g / cm 3 , e.g., 0.25 g / cm 3 ~0.29g / cm 3 , e.g., 0.26 g / cm 3 ~0.275g / cm 3 , e.g., 0.269 g / cm 3It will be appreciated that the second longitudinally extending core may have a wrapper (e.g., second core wrapper) that holds the filtering material in an appropriate shape (e.g., in a core form, e.g., a rod form or a plug form). This wrapper (e.g., second core wrapper) is separate from the wrappers (e.g., filter wrappers) engaged around the first and second longitudinally extending cores, for example. It will be appreciated that if a wrapper (e.g., second core wrapper) for the second longitudinally extending core is present, the wrappers (e.g., filter wrappers) engaged around the first and second longitudinally extending cores are wrapped around the wrapper (e.g., second core wrapper) of the second longitudinally extending core as well as the second longitudinally extending core itself.

[0011] The filter may further include a third longitudinally extending core. The third longitudinally extending core comprises a third filtering material (e.g., paper, e.g., uncoated paper, coated paper, siliconized paper, e.g., ZNP paper), and the third longitudinally extending core has a pressure drop of 0.5 to 0.6 mmWG per mm of its length. The third longitudinally extending core comprises paper and / or other biodegradable materials (e.g., non-cellulose acetate-containing materials). When the third longitudinally extending core is present, a wrapper (e.g., a filter wrapper) is engaged around the first, second, and third longitudinally extending cores. The third longitudinally extending core has a pressure drop of 0.1 to 1 mmWG per mm of length, for example, 0.31 to 0.7 mmWG per mm of length, for example, 0.5 to 0.6 mmWG per mm of length, for example, 0.53 to 0.57 mmWG per mm of length, for example, 0.55 mmWG per mm of length. Preferably, the third longitudinally extending core has a pressure drop of 0.5 to 0.6 mmWG per mm of length, for example, 0.53 to 0.57 mmWG per mm of length, for example, 0.55 mmWG per mm of length. The third longitudinally extending core may, for example, be positioned between the first longitudinally extending core and the second longitudinally extending core. The third longitudinally extending core may be formed from paper (e.g., uncoated paper, coated paper, siliconized paper, e.g., ZNP paper) and / or other biodegradable material, which is laterally gathered into a rod form and held in place (e.g., by a wrapper, e.g., the third core wrapper). The third longitudinally extending core may be formed from paper (e.g., uncoated paper, coated paper, siliconized paper, e.g., ZNP paper) and / or other biodegradable material, which is laterally gathered into a rod form and held in place (e.g., by a wrapper, e.g., the third core wrapper), and has a width of 250 to 350 mm, such as 251 to 350 mm, for example 280 to 320 mm, for example 300 mm.It will be appreciated that the third longitudinally extending core may have a wrapper (e.g., a third core wrapper) that holds the filtering material in an appropriate shape (e.g., in a core form, e.g., a rod form or a plug form). This wrapper (e.g., a third core wrapper) is separate from the wrappers (e.g., filter wrappers) that are engaged around the first and second (and third) longitudinally extending cores. It will be appreciated that when a wrapper (e.g., a third core wrapper) for the third longitudinally extending core is present, the wrappers (e.g., filter wrappers) engaged around the first and second (and third) longitudinally extending cores are wrapped around the third longitudinally extending core's wrapper (e.g., the third core wrapper) as well as the third longitudinally extending core itself.

[0012] Applicants have surprisingly found that filters according to embodiments of the present invention combine biodegradability ("readily biodegradable") with a comparable thermal profile and / or comparable aerosol chemical delivery to marketed products that use cellulose acetate and PLA. Additionally, Applicants have found that filters of the present invention are adaptable to provide customizable designs to match desired aerosol chemical delivery profiles.

[0013] The first filtering material may comprise readily biodegradable paper and / or other biodegradable materials. The second filtering material may comprise readily biodegradable paper and / or other biodegradable materials. Preferably, each of the first and second filtering materials comprises readily biodegradable paper and / or other biodegradable materials.

[0014] As used herein, the term "biodegradable" refers to filtering materials and filters that can exhibit at least 90% biodegradation after 6 months under controlled composting conditions (see ISO 14855-1 Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions - Method by analysis of evolved carbon dioxide).

[0015] Preferably, the paper and / or other biodegradable materials (e.g., non-cellulose acetate-containing materials) used in the filtering material(s) of the filters of the present invention are "readily biodegradable" and have improved biodegradability compared to cellulose acetate. Thus, the present invention provides a filter with improved biodegradability, and is therefore more environmentally friendly and more compliant with EU legislation.

[0016] As used herein, the phrase "readily biodegradable" refers to the filtering material and filter's ability to rapidly disintegrate and completely biodegrade when immersed in water. Preferably, the filter (and the filtering material used therein) has a "Ready Biodegradability" level of biodegradability, as measured according to the OECD 301B "Ready Biodegradability" method (modified Sturm test), which is well known in the art. The phrase "readily biodegradable" is understood herein to mean a "ready biodegradable" level of biodegradability.

[0017] The paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) is preferably readily biodegradable. The paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) can be composed of any paper (in any form) conventionally used in filters or filter elements. The paper can be, for example, various grades of filter paper, aperture paper, crepe paper, airlaid paper, or machine-glazed paper. The fibers of the paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) can be natural fibers (e.g., flax, hemp, sisal, jute, abaca, cotton, coconut fiber, bamboo fiber, starch (e.g., from corn), or tobacco) or any roll material. The paper can be woven or nonwoven, and can be in the form of a coherent web of paper, or a longitudinally corrugated and / or fibrillated web of paper, for example, laterally gathered and held in the form of a plug. The paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) may be in the form of a coherent web comprising a first paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) and a second paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material). The paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) may be in the form of a blend of different paper materials and / or other biodegradable materials (e.g., non-cellulose acetate-containing filtering materials). The paper filtering material may have the same or similar structure as papers sold under the trade names Myria® or Puracel® (by Essentra plc).

[0018] The first filtering material may include readily biodegradable paper and / or other biodegradable materials. The first filtering material may include paper and / or other biodegradable materials as described in the paragraph above. In some examples, the first filtering material includes Puracel FM26, Puracel FM36, and / or Greenbutts.

[0019] The second filtering material may include readily biodegradable paper and / or other biodegradable materials. The second filtering material may include paper and / or other biodegradable materials as described above. In some examples, the second filtering material includes uncoated paper, coated paper, and / or siliconized paper.

[0020] The third filtering material may include readily biodegradable paper and / or other biodegradable materials. The third filtering material may include paper and / or other biodegradable materials as described above. In some examples, the third filtering material includes uncoated paper, coated paper, and / or siliconized paper.

[0021] Preferably, the first filtering material comprises paper having a basis weight of 20 gsm to 200 gsm. For example, the first filtering material may be paper having a basis weight of 40 gsm to 180 gsm, such as 60 gsm to 160 gsm, for example 80 gsm to 140 gsm, for example 100 gsm to 120 gsm, such as 20 gsm to 60 gsm, for example 30 gsm to 40 gsm.

[0022] Preferably, the second filtering material comprises paper having a basis weight of 20 gsm to 200 gsm. For example, the second filtering material may be paper having a basis weight of 40 gsm to 180 gsm, such as 60 gsm to 160 gsm, for example 80 gsm to 140 gsm, for example 100 gsm to 120 gsm, such as 20 gsm to 60 gsm, for example 30 gsm to 40 gsm.

[0023] Preferably, the third filtering material comprises paper having a basis weight of 20 gsm to 200 gsm. For example, the third filtering material may be paper having a basis weight of 40 gsm to 180 gsm, such as 60 gsm to 160 gsm, for example 80 gsm to 140 gsm, for example 100 gsm to 120 gsm, for example 20 gsm to 60 gsm, for example 30 gsm to 40 gsm.

[0024] The filter of the present invention may be cylindrical, having a circumference of 12 to 30 mm (e.g., 15 to 28 mm), more preferably 17 to 25 mm (e.g., 18 to 25 mm, e.g., 20 to 24 mm, e.g., 22 to 24 mm, e.g., 23 mm, e.g., 22 mm, e.g., 22.45 mm).

[0025] The wrappers (e.g., filter wrappers) engaged around the first and second (and optionally, third) longitudinally extending cores may be paper (e.g., plug wrap), preferably a paper (e.g., plug wrap) having a basis weight of 20 to 160 gsm, for example, a paper (e.g., plug wrap) having a basis weight of 24 to 150 gsm, for example, a paper (e.g., plug wrap) having a basis weight of 70 to 150 gsm, for example, a paper (e.g., plug wrap) having a basis weight of 70 to 140 gsm. Preferably, the wrappers (e.g., filter wrappers) engaged around the first and second (and optionally, third) longitudinally extending cores are biodegradable, more preferably readily biodegradable.

[0026] The wrapper for the first longitudinally extending core (e.g., first core wrapper), if present, and / or the wrapper for the second longitudinally extending core (e.g., second core wrapper), if present, may be paper (e.g., plug wrap). The paper may be paper (e.g., plug wrap) having a basis weight of 20 to 160 gsm, for example, paper (e.g., plug wrap) having a basis weight of 24 to 150 gsm, for example, paper (e.g., plug wrap) having a basis weight of 70 to 150 gsm, for example, paper (e.g., plug wrap) having a basis weight of 70 to 140 gsm. Preferably, the wrapper for the first longitudinally extending core (e.g., first core wrapper), if present, and the wrapper for the second longitudinally extending core (e.g., second core wrapper), if present, are biodegradable, more preferably readily biodegradable. The wrapper for the first longitudinally extending core (e.g., first core wrapper) and the wrapper for the second longitudinally extending core (e.g., second core wrapper) may be made from the same material or from different materials.

[0027] The wrapper for the third longitudinally extending core (e.g., third core wrapper) may be paper (e.g., plug wrap). The paper may be paper (e.g., plug wrap) having a basis weight of 20 to 160 gsm, for example, paper (e.g., plug wrap) having a basis weight of 24 to 150 gsm, for example, paper (e.g., plug wrap) having a basis weight of 70 to 150 gsm, for example, paper (e.g., plug wrap) having a basis weight of 70 to 140 gsm. Preferably, the wrapper for the third longitudinally extending core (e.g., third core wrapper), if present, is biodegradable, more preferably readily biodegradable.

[0028] The filter of the present invention may have a length of 18 mm to 60 mm, for example, 20 to 50 mm (for example, 20 to 35 mm). Preferably, the filter of the present invention has a length of 30 to 35 mm, for example, 31 mm to 34 mm, for example, 33 mm.

[0029] The first longitudinally extending core may be 3 to 18 mm in length, such as 3 to 11 mm, for example 6 to 10 mm, for example 6, 7, 8, 9, or 10 mm in length.

[0030] The second longitudinally extending core may be from 7 to 30 mm in length, such as from 17 to 25 mm, for example from 18 to 24 mm, for example 18, 19, 20, 21, 22, 23 or 24 mm in length.

[0031] The third longitudinally extending core, if present, may be from 3 to 18 mm in length, such as from 3 to 11 mm, for example from 6 to 10 mm, for example 6, 7, 8, 9, or 10 mm in length.

[0032] The cavity between the first longitudinally extending core and the second longitudinally extending core, if present, may be 4 to 10 mm in length, for example 5 to 9 mm, for example 5, 6, 7, 8, or 9 mm in length.

[0033] Preferably the filter has a pressure drop (longitudinal along the entire length of the filter) of 10 to 50 mmWG, such as 23 to 35 mmWG, for example 24 to 31 mmWG, for example 28 to 31 mmWG.

[0034] In one example, a filter of the present invention is 33 mm long and includes a first longitudinally extending core having a length of 10 mm, a second longitudinally extending core having a length of 18 mm, and a cavity between the first and second longitudinally extending cores having a length of 5 mm. This example is shown in accompanying Figure 1.

[0035] In another example, a filter of the present invention is 33 mm long and includes a first longitudinally extending core that is 8 mm long, a second longitudinally extending core that is 18 mm long, and a cavity between the first and second longitudinally extending cores that is 7 mm long.

[0036] In a further example, a filter of the present invention is 33 mm long and includes a first longitudinally extending core that is 6 mm long, a second longitudinally extending core that is 18 mm long, and a cavity between the first and second longitudinally extending cores that is 9 mm long.

[0037] In yet a further example, the filter of the present invention is 33 mm long and includes a first longitudinally extending core 9 mm long abutting a second longitudinally extending core 24 mm long. In this example, there is no cavity between the first longitudinally extending core and the second longitudinally extending core. This example is shown in accompanying Figure 2.

[0038] In a further example, a filter of the present invention is 33 mm long and includes a first longitudinally extending core having a length of 8 mm, a second longitudinally extending core having a length of 18 mm, and a third longitudinally extending core between the first and second longitudinally extending cores having a length of 7 mm. In this example, there is no cavity between the first and second longitudinally extending cores.

[0039] The paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) of the first and / or second longitudinally extending cores may be coated with a hydrophobic coating or hydrophobic material. Without being bound by theory, it is believed that the hydrophobic material within the filtering material causes water vapor within the element (e.g., cooling element) to condense within the element (e.g., cooling element), which provides a beneficial effect of cooling the vapor as it passes through the element. Preferably, the hydrophobic material is distributed throughout the longitudinally extending (e.g., cylindrical) core(s). Applicants have found that this provides an optimal level of vapor cooling and filtering for use in tobacco heating products or HNB products. The hydrophobic coating / material may be any suitable hydrophobic material. For example, the hydrophobic coating / material may be a polymer or a blend of polymers. Preferably, the hydrophobic coating / material is a starch, such as a modified starch, e.g., oxidized starch (E1404). Starches, such as modified starches, are preferred because they provide an inert, non-plasticizing hydrophobic coating. The hydrophobic coating / material may be present in an amount of 0.01% to 50% by weight (w / w), for example, 0.01% to 20% w / w, for example, 0.1% to 20% w / w, for example, 5% to 20% w / w, for example, 10% to 20% w / w, for example, 0.1% to 10% w / w, for example, 0.1% to 5% w / w, for example, 0.5% to 2.5% w / w, based on the weight of the associated longitudinally extending core. The hydrophobic coating can be applied to the paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) of the first and / or second longitudinally extending cores via any of the standard coating methods known in the art.

[0040] Preferably, the filter has a substantially circular cross-section, meaning that the element is substantially cylindrical in shape. However, the filter of the present invention may have any shape. For example, the filter may have a circular or elliptical cross-section, or a square or rectangular cross-section.

[0041] It will be understood that the filters of the present invention can be used in any multi-segment filter or consumable. A multi-segment filter may include one, two, three, four, or more additional separate segments. The additional separate segments may be (e.g., cylindrical) plugs of tobacco smoke filtering material (e.g., paper) and / or hollow (e.g., paper) tube filters. A multi-segment filter may be attached to a tobacco plug (which can be made from any form of tobacco, including reconstituted). A multi-segment filter may also include other filter segments, including capsule-containing filters, carbon-containing filters, CPS filters, tube filters, paper filters, menthol-containing filters, etc.

[0042] According to a further aspect, the present invention provides a (e.g., biodegradable, e.g., readily biodegradable) filter element comprising a longitudinally extending (e.g., substantially cylindrical) core having a pressure drop of 0.1 to 1 mmWG per mm of length, e.g., 0.31 to 0.7 mmWG per mm of length, e.g., 0.5 to 0.6 mmWG per mm of length (e.g., a pressure drop of 0.53 to 0.57 mmWG per mm of length, e.g., a pressure drop of 0.55 mmWG per mm of length), and the longitudinally extending (e.g., substantially cylindrical) core comprises a filtering material comprising paper and / or other biodegradable material (e.g., a non-cellulose acetate-containing material). The filter element may also have a wrapper (e.g., core wrapper), e.g., a paper wrapper, e.g., a biodegradable and / or readily biodegradable paper wrapper, engaged around the longitudinally extending core. The longitudinally extending core may be formed from paper (e.g., uncoated paper, coated paper, siliconized paper, e.g., ZNP paper) and / or other biodegradable material, which is laterally gathered into a rod form and held in place (e.g., by a wrapper, e.g., a core wrapper). The longitudinally extending core may be formed from paper (e.g., uncoated paper, coated paper, siliconized paper, e.g., ZNP paper) and / or other biodegradable material, which is laterally gathered into a rod form and held in place (e.g., by a wrapper, e.g., a core wrapper), having a width of 250 to 350 mm, such as 251 to 350 mm, for example 280 to 320 mm, for example 300 mm. Preferably, the longitudinally extending (e.g., substantially cylindrical) core has a pressure drop of 0.5 to 0.6 mmWG per mm of length, such as a pressure drop of 0.53 to 0.57 mmWG per mm of length, for example a pressure drop of 0.55 mmWG per mm of length. Preferably, the longitudinally extending (e.g., substantially cylindrical) core has a pressure drop of 0.215 g / cm 3 ~0.33g / cm 3 , e.g., 0.22 g / cm 3 ~0.31g / cm 3 , e.g., 0.24 g / cm 3 ~0.30g / cm 3 , e.g., 0.25 g / cm 3~0.29g / cm 3 , e.g., 0.26 g / cm 3 ~0.275g / cm 3 , e.g., 0.269 g / cm 3 It has a density of .

[0043] The filter element has a cooling effect (e.g., on aerosols drawn through any filter including a longitudinally extending core and / or filter element). As used herein, the term "element" or "filter element" will be understood to refer to any discrete segment that may be used in a filter or aerosol-generating article. The element may also be a cooling element. As used herein, the term "cooling element" will be understood to refer to a discrete segment that provides a significant cooling function, i.e., the ability to reduce the temperature of the aerosol or vapor as it passes along the length of the element.

[0044] As used herein, the term "biodegradable" refers to filtering materials and filter elements that can exhibit at least 90% biodegradation after six months under controlled composting conditions (see ISO 14855-1 Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions—Method by analysis of evolved carbon dioxide). Preferably, the paper and / or other biodegradable materials (e.g., non-cellulose acetate-containing materials) used in the filtering material of the (filter) element of the present invention are "easily biodegradable," meaning they have improved biodegradability compared to cellulose acetate. Thus, the present invention provides filter elements with improved biodegradability, which are therefore more environmentally friendly and more compliant with EU legislation.

[0045] As used herein, the phrase "readily biodegradable" refers to the filtering material and element being capable of rapidly disintegrating and completely biodegrading when immersed in water. Preferably, the element has a "Ready Biodegradability" level of biodegradability as measured according to the OECD 301B "Ready Biodegradability" method (modified Sturm test), which is well known in the art. The phrase "readily biodegradable" is understood herein to mean a "ready biodegradable" level of biodegradability.

[0046] The paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) is preferably readily biodegradable. The paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) can be composed of any paper (in any form) conventionally used in filters or filter elements. The paper can be, for example, various grades of filter paper, aperture paper, crepe paper, airlaid paper, or machine-glazed paper. The fibers of the paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) can be natural fibers (e.g., flax, hemp, sisal, jute, abaca, cotton, coconut fiber, bamboo fiber, starch (e.g., from corn), or tobacco) or any roll material. The paper can be woven or nonwoven, and can be in the form of a coherent web of paper, or a longitudinally corrugated and / or fibrillated web of paper, for example, laterally gathered and held in the form of a plug. The paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) may be in the form of a coherent web comprising a first paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) and a second paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material). The paper and / or other biodegradable material (e.g., non-cellulose acetate-containing filtering material) may be in the form of a blend of different paper materials and / or other biodegradable materials (e.g., non-cellulose acetate-containing filtering materials). The paper filtering material may have the same or similar structure as papers sold under the trade names Myria® or Puracel® (by Essentra plc).

[0047] The filtering material may comprise readily biodegradable paper and / or other biodegradable materials. The filtering material may comprise paper and / or other biodegradable materials as described above. In some examples, the filtering material comprises uncoated paper, coated paper, and / or siliconized paper. Preferably, the filtering material comprises paper having a basis weight of 20 gsm to 200 gsm. For example, the filtering material may be paper having a basis weight of 40 gsm to 180 gsm, such as 60 gsm to 160 gsm, such as 80 gsm to 140 gsm, such as 100 gsm to 120 gsm, such as 20 gsm to 60 gsm, or such as 30 gsm to 40 gsm. The filter element of the present invention may be cylindrical. The filter element of the present invention may be cylindrical with a circumference of 12 to 30 mm (e.g., 15 to 28 mm), more preferably 17 to 25 mm (e.g., 18 to 25 mm, e.g., 20 to 24 mm, e.g., 22 to 24 mm, e.g., 23 mm, e.g., 22 mm, e.g., 22.45 mm).

[0048] The wrapper (e.g., core wrapper) engaged around the longitudinally extending core may be paper (e.g., plug wrap), preferably paper (e.g., plug wrap) having a basis weight of 20 to 160 gsm, for example, paper (e.g., plug wrap) having a basis weight of 24 to 150 gsm, for example, paper (e.g., plug wrap) having a basis weight of 70 to 150 gsm, for example, paper (e.g., plug wrap) having a basis weight of 70 to 140 gsm. Preferably, the wrapper (e.g., core wrapper) engaged around the longitudinally extending core is biodegradable, more preferably readily biodegradable.

[0049] The filter element (and longitudinally extending core) may be from 7 to 30mm in length, such as from 17 to 25mm, for example from 18 to 24mm, for example 7, 8, 9, 10, 18, 19, 20, 21, 22, 23 or 24mm in length.

[0050] The paper and / or other biodegradable material (eg, non-cellulose acetate-containing filtering material) of the longitudinally extending core may be coated with a hydrophobic coating or material, as described above.

[0051] It will be understood that the filter element of the present invention can be used in any multi-segment filter or consumable. The filter structure may be two, three, four, or more separate segments. The separate additional segments may be (e.g., cylindrical) plugs of tobacco smoke filtering material (e.g., paper) and / or hollow (e.g., paper) tube filters. The multi-segment filter may be attached to a tobacco plug (which can be made from any form of tobacco, including reconstituted). The multi-segment filter may also include other filter segments, including capsule-containing filters, carbon-containing filters, CPS filters, tube filters, paper filters, menthol-containing filters, etc.

[0052] It will be appreciated that filters or filter elements according to the present invention may be manufactured by methods and machines well known in the art.

[0053] According to a further aspect, the present invention provides an aerosol-generating article (eg, a cigarette, e.g., a tobacco heating product, HNB product) comprising a filter or filter element according to any aspect of the present invention.

[0054] The filters or filter elements of the present invention are suitable for use with any type of tobacco blend.

[0055] In an aerosol-generating article according to the present invention, a filter of the present invention (or a filter comprising a filter element of the present invention) may be joined to a wrapped plug of tobacco (e.g., a wrapped plug of improved tobacco, as is well known in the art). The filter of the present invention (or a filter comprising a filter element of the present invention) may be joined to the wrapped tobacco plug so that a (second) longitudinally extending core having a pressure drop of 0.1 to 1 mmWG per mm of its length, for example 0.31 to 0.7 mmWG per mm of its length, for example 0.5 to 0.6 mmWG per mm of its length (e.g., 0.55 mmHG per mm), is adjacent to the tobacco plug. The filter may be joined to the wrapped tobacco plug by ring tipping (i.e., an outer wrapper (e.g., tipping paper) that engages only around the adjacent ends of the wrapped filter and tobacco plug, leaving much of the filter wrap exposed). The filter may be joined to the wrapped tobacco plug with a complete tipping overlap (i.e., an outer wrapper (e.g., tipping paper) engaging around the entire length of the wrapped filter and the adjacent end of the tobacco plug). The wrapper (e.g., filter wrapper) may be ventilated, for example, by laser perforation. Ventilation may be applied to the wrapper (e.g., filter wrapper) before or after the filter is joined to the wrapped tobacco plug. Ventilation may be aligned (applied to the wrapper) with cavities (if present) in the filter.

[0056] Tobacco heating products and / or HNB products or HTPs according to the present invention may further comprise one or more separate additional segments (e.g., of an HNB mouthpiece), which may be a (e.g., cylindrical) plug of tobacco smoke filtering material (e.g., paper), a (e.g., cylindrical) rod of tobacco (e.g., tobacco of any form (including reconstituted tobacco)), a hollow (e.g., paper) tube, a capsule-containing filter, a carbon-containing filter, a CPS filter, a tube filter, an acetate filter, a paper filter, a menthol-containing filter, etc. [Brief explanation of the drawings]

[0057] The present invention will now be described in more detail with reference to the accompanying drawings.

[0058] [Figure 1] 1 shows a cutaway perspective view of a filter according to an embodiment of the present invention, including a filter element according to a further embodiment of the present invention; [Figure 2] 2 shows a cutaway perspective view of a filter according to a further embodiment of the invention (different from that of FIG. 1) including a filter element according to a still further embodiment of the invention; [Figure 3] 1 is a graph showing how the temperature at the mouth end of HTPs comprising filters and filter elements according to the invention (Examples SAM111426-10-150, SAM111426-8-150 and SAM111426-6-150) and the reference product Amber HEETS varies as a puff is taken (see Example 1).

[0059] 1 shows a cutaway perspective view of a filter 1 for use in an aerosol-generating article (e.g., a tobacco heating product and / or an HNB product and / or an HTP). Filter 1 is cylindrical, 33 mm long and 22.45 mm in circumference.

[0060] The filter 1 includes, at its mouth end 2, a first longitudinally extending cylindrical core 3 having a circumference of 22.45 mm and a length of 10 mm. The first longitudinally extending cylindrical core 3 is gathered together transversely in a plug form and held in place with a first core wrapper 5 of Puracel FM26 paper (300 mm Puracel® FM26 g / m²) weighing 78 gsm and non-porous plug wrap (manufactured by Mudanjiang Hengfeng Paper Co., Ltd., Mundanjiang, China). 2 It is formed from a plug of a first filtering material in the form of a sheet of SWM (manufactured by Essentra plc).

[0061] The filter 1 also includes a second longitudinally extending cylindrical core 7 longitudinally spaced 5 mm from the first longitudinally extending cylindrical core 3. The second longitudinally extending cylindrical core 7 has a circumference of 22.45 mm and a length of 18 mm. The second longitudinally extending cylindrical core 7 includes a plug of second filtering material in the form of a 300 mm wide sheet of ZNP paper (obtained from PT Bukit Muria Jaya (BMJ) in West Java, Indonesia) gathered transversely into a rod and held in place with a second core wrapper 9 of 78 gsm non-porous plug wrap (manufactured by Mudanjiang Hengfeng Paper Co., Ltd. in Mundanjiang, China). The second longitudinally extending core has a pressure drop of 0.55 mmWG per mm of its length.

[0062] Weight 78g / m 2 A stiff plug wrap further filter wrapper 11 (manufactured by Mudanjiang Hengfeng Paper Co., Ltd., Mundanjiang, China) is engaged around the wrapped longitudinally extending cores 3 and 7 to define a 5 mm long cavity 13 between the wrapped longitudinally extending cores 3 and 7. Both ends of the further wrapper 11 are flush with the ends of the wrapped cores 3 and 7. The filter wrapper 11 has overlapping longitudinal edges coated with adhesive, which provide overlapping and glued seams (not shown) that hold the further wrapper 11 around the wrapped cores 3 and 7, and further adhesive in anchor lines (not shown) aligned with the wrapped cores 3 and 7 to hold the cores in place.

[0063] The first and second longitudinally extending cores 3 and 7, their respective first and second core wrappers 5 and 9, and the filter wrapper 11 are all made of paper materials and are all "readily biodegradable," meaning that the filter 1 (and the materials therein) are capable of rapidly disintegrating and completely biodegrading when immersed in water such that the filter 1 (and the materials therein) have a "Ready Biodegradability" level of biodegradability, as measured according to the OECD 301B "Ready Biodegradability" method (modified Sturm test), which is well known in the art.

[0064] Applicants have surprisingly found that filters such as Filter 1 combine biodegradability ("readily biodegradable") with a comparable thermal profile and / or comparable aerosol chemical delivery to marketed products that use cellulose acetate and PLA (see Example 1 below). Additionally, Applicants have found that the filters of the present invention are adaptable to provide customizable designs to match desired aerosol chemical delivery profiles.

[0065] It will be appreciated that filter 1 may be made by methods known in the art and may be prepared as multiple (e.g., 2, 4, 6, etc.) filters or multiple rods, including filter rods joined together end-to-end.

[0066] The filter 1 may be joined at its end opposite the mouth end 2 to a wrapped plug of improved tobacco by methods well known in the art. A suitable reconstituted tobacco plug is 12 mm in length and 22 mm in circumference. Such reconstituted tobacco plugs are well known in the art. The filter and tobacco plug together form an HNB product or HTP containing the filter 1 of the present invention.

[0067] In use, the tobacco plug end of an HNB product or HTP containing the filter 1 of the present invention is inserted into an HTP device. The plug is heated in use by a heating device (HTP device) to generate vapor, as is well known in the art. This generates hot vapor, which is drawn first through the second longitudinally extending cylindrical core 7, through the cavity 13, and through the first longitudinally extending cylindrical core 3 to the smoker's mouth (i.e., the mouth end). Drawing this hot vapor through the second longitudinally extending core 7 at a pressure drop of 0.55 mmWG per mm of its length is believed to have a cooling effect (e.g., on the aerosol drawn through the second longitudinally extending core and / or filter) that cools the vapor to a temperature acceptable to the user.

[0068] Figure 2 shows a schematic diagram of a further embodiment of the present invention. Figure 2 shows a filter 101 for use in an aerosol-generating article (e.g., a tobacco heating product and / or an HNB product and / or an HTP). The filter 101 is cylindrical with a length of 33 mm and a circumference of 22.45 mm.

[0069] The filter 101 includes, at its mouth end 102, a first longitudinally extending cylindrical core 103 having a circumference of 22.45 mm and a length of 9 mm. The first longitudinally extending cylindrical core 103 is gathered together transversely in a plug form and held in place with a first core wrapper 105 of Puracel FM26 paper (300 mm Puracel® FM26 g / m²) that is non-porous plug wrap weighing 78 gsm (obtained from Mudanjiang Hengfeng Paper Co., Ltd., Mundanjiang, China). 2 It is formed from a plug of a first filtering material in the form of a sheet of SWM (manufactured by Essentra plc).

[0070] The filter 101 also includes a second longitudinally extending cylindrical core 107, which abuts the first longitudinally extending cylindrical core 103 at the end opposite the mouth end 102. The second longitudinally extending cylindrical core 107 has a circumference of 22.45 mm and a length of 24 mm. The second longitudinally extending cylindrical core 107 contains a plug of second filtering material in the form of a 300 mm wide sheet of ZNP paper (obtained from PT Bukit Muria Jaya (BMJ) in West Java, Indonesia) gathered transversely into a rod and held in place with a second core wrapper 109 of 78 gsm non-porous plug wrap (manufactured by Mudanjiang Hengfeng Paper Co., Ltd. in Mundanjiang, China). The second longitudinally extending core has a pressure drop of 0.55 mmWG per mm of its length.

[0071] Weight 78g / m 2 A stiff plug wrap additional filter wrapper 111 (manufactured by Mudanjiang Hengfeng Paper Co., Ltd., Mundanjiang, China) is engaged around the wrapped cores 103 and 107. Both ends of the additional wrapper 111 are flush with the ends of the wrapped cores 103 and 107. The additional wrapper 111 has overlapping longitudinal edges coated with adhesive, which provide an overlapping and attached seam (not shown) that holds the additional wrapper 111 around the wrapped cores 103 and 107, and additional adhesive in anchor lines (not shown) aligned with the wrapped cores 103 and 107 to hold the cores in place.

[0072] The first and second longitudinally extending cores 103 and 107, their respective first and second core wrappers 105 and 109, and the further wrapper 111 are all made of paper materials and are all "ready biodegradable", meaning that the filter 101 (and the materials therein) are capable of rapidly disintegrating and completely biodegrading when immersed in water such that the filter 101 (and the materials therein) have a "Ready Biodegradability" level of biodegradability, as measured according to the OECD 301B "Ready Biodegradability" method (modified Sturm test), which is well known in the art.

[0073] Applicants have surprisingly found that filters such as filter 101 combine biodegradability ("readily biodegradable") with a comparable thermal profile and / or comparable aerosol chemical delivery to marketed products that use cellulose acetate and PLA. Additionally, applicants have found that the filters of the present invention are adaptable to provide customizable designs to match desired aerosol chemical delivery profiles.

[0074] Example 1 - Experimental A 33 mm long filter according to the invention, as shown in Figure 1 and including a 10 mm long first longitudinally extending core (FM26 paper), an 18 mm long second longitudinally extending core (ZNP paper), and a 5 mm long cavity between the first and second longitudinally extending cores, was attached to a plug of reconstituted tobacco by methods well known in the art to provide a test HNB product or HTP, designated Test Example SAM111426-10-150 (abbreviated as SAM426-10-150).

[0075] Similarly, a second filter according to the present invention, measuring 33 mm in length and including an 8 mm long first longitudinally extending core (FM26 paper), an 18 mm long second longitudinally extending core (ZNP paper), and a 7 mm long cavity between the first and second longitudinally extending cores, was attached to a plug of reconstituted tobacco by methods well known in the art to provide a test HNB or HTP product, designated Test Example SAM111426-8-150 (abbreviated as SAM426-8-150).

[0076] A third filter according to the present invention, measuring 33 mm in length and including a first longitudinally extending core (FM26 paper) measuring 6 mm in length, a second longitudinally extending core (ZNP paper) measuring 18 mm in length, and a 9 mm in length cavity between the first and second longitudinally extending cores, was attached to a plug of reconstituted tobacco by methods well known in the art to provide a test HNB or HTP product, designated Test Example SAM111426-6-150 (abbreviated as SAM426-6-150).

[0077] The reference product, Amber HEETS, includes a plug of reconstituted tobacco and a 3 mm long filter comprising a 7 mm long hollow acetate tube (tobacco end), an 18 mm long PLA cooling element, referred to herein as the "conventional cooling element," and an 8 mm long mouth-end cylindrical plug of cellulose acetate tow in an arrangement similar to that shown in FIG. 1.

[0078] HNB test examples SAM111426-10-150, SAM111426-8-150 and SAM111426-6-150 and the benchmark Amber HEETS were compared as follows:

[0079] Each product was inserted into a heating device. The mouth-end of the product was inserted into a smoking machine configured to smoke the product. An IR camera was used to analyze the temperature of the mouth-end of the product during smoking. The smoking machine was configured to take a puff on the product every 30 seconds, with each puff lasting 2 seconds. The temperature at the mouth-end of the product was measured for each puff. The experiment was conducted at standard room temperature and humidity. The experiment was repeated for each example product, i.e., SAM111426-10-150, SAM111426-8-150, SAM111426-6-150, and the reference product, Amber HEETS.

[0080] 3 is a graph showing how the temperature at the mouth end of HNB products / THPs containing filters and filter elements according to the present invention (Examples SAM111426-10-150, SAM111426-8-150, and SAM111426-6-150) and the reference product Amber HEETS varies as a puff progresses. The figure shows that the paper-based filters of the present invention can provide cooling effects comparable to those of conventional cooling elements, while offering the significant advantage of being readily biodegradable.

[0081] The temperature change, nicotine, and aerosol collection mass yield of products SAM111426-10-150 and SAM111426-6-150 (each containing a filter according to the present invention) and the reference product Amber HEETS were measured by methods well known in the art (ISO 3308:2012 Routine analytical cigarette-smoking machine—Definitions and standard conditions). The results are shown in Table 1. [Table 1] *This is hotter than the standard, but is acceptable as it is less than 5% hotter than the standard.

[0082] Table 1 (and FIG. 3) shows that filters and elements according to the present invention can provide comparable thermal profiles and / or comparable aerosol chemical delivery performance to conventional cooling elements (the benchmark), while also providing improved biodegradability (because they do not contain, for example, PLA elements).

Claims

1. 1. A filter for use in an aerosol-generating article, said filter comprising: a first longitudinally extending core including a first filtering material; a second longitudinally extending core comprising a second filtering material, said second longitudinally extending core having a pressure drop of 0.1 to 1 mmWG per mm of its length, for example 0.31 to 0.7 mmWG per mm of its length, for example 0.5 to 0.6 mmWG per mm of its length, for example 0.55 mmWG per mm of its length; a wrapper engaged about the first longitudinally and second longitudinally extending core; each of the first filtering material and the second filtering material comprises paper and / or other biodegradable material; A filter wherein the second longitudinally extending core is formed from paper and / or other biodegradable material that is gathered laterally into a rod form and held in place (e.g., by a wrapper).

2. 10. The filter of claim 1, wherein the second longitudinally extending core has a cooling effect on aerosols drawn therethrough.

3. 3. The filter of claim 1, wherein the first longitudinally extending core is longitudinally spaced from the second longitudinally extending core such that the wrapper defines a cavity between the first longitudinally extending core and the second longitudinally extending core.

4. 4. A filter according to any one of claims 1 to 3, wherein the second longitudinally extending core is formed from paper and / or other biodegradable material having a width of 20mm to 350mm, such as a width of 200mm to 350mm, for example 250-350mm, such as 251-350mm, for example 280-320mm, for example 300mm, and the paper and / or other biodegradable material is gathered laterally into a rod form and held in place (for example by a wrapper).

5. The filter of any one of claims 1 to 4, wherein the first filtering material and the second filtering material each comprise readily biodegradable paper and / or other biodegradable material.

6. 6. A filter according to any one of the preceding claims, wherein the filter is cylindrical with a circumference of 12 to 30mm (e.g. 15 to 28mm), more preferably 17 to 25mm (e.g. 18 to 25mm, for example 20 to 24mm, such as 22 to 24mm, for example 23mm, such as 22mm, for example 22.45mm).

7. A filter according to any preceding claim, having a length of 18 to 60 mm, for example 30 to 35 mm, for example 33 mm.

8. A filter according to any preceding claim, wherein the first longitudinally extending core is 3 to 18 mm in length, such as 3 to 11 mm, for example 6 to 10 mm in length.

9. A filter according to any preceding claim, wherein the second longitudinally extending core is from 7 to 30 mm in length, such as from 17 to 25 mm, for example from 18 to 24 mm.

10. 10. A filter according to any preceding claim, comprising a cavity between the first longitudinally extending core and the second longitudinally extending core, the cavity being 3 to 18 mm in length, such as 4 to 10 mm in length, for example 5 to 9 mm in length.

11. 1. A filter element comprising a longitudinally extending core, the longitudinally extending core having a pressure drop of 0.1 to 1 mmWG per mm of length, e.g., 0.31 to 0.7 mmWG per mm of length, for example, 0.5 to 0.6 mmWG per mm of length (e.g., a pressure drop of 0.53 to 0.57 mmWG per mm of length, e.g., a pressure drop of 0.55 mmWG per mm of length), the longitudinally extending (e.g., substantially cylindrical) core comprising a filtering material comprising paper and / or other biodegradable material (e.g., a non-cellulose acetate-containing material), and a wrapper engaged around the longitudinally extending core, the longitudinally extending core being formed from paper and / or other biodegradable material that is gathered laterally into a rod form and held in place by the wrapper.

12. 12. A filter element according to claim 11, wherein the longitudinally extending core is formed from paper and / or other biodegradable material having a width of 20mm to 350mm, for example 200mm to 350mm, such as a width of 250-350mm, for example 251-350mm, such as 280-320mm, for example 300mm, and the paper and / or other biodegradable material is gathered laterally into a rod form and held in place (for example by the wrapper).

13. 13. An aerosol-generating article (e.g. tobacco heating product, HNB product) comprising a filter according to any one of claims 1 to 10, or comprising a filter comprising a filter element according to claim 11 or 12 and, optionally, one or more separate further segments.

14. 13. A tobacco heating product and / or HNB product and / or HTP comprising a filter according to any one of claims 1 to 10, or comprising a filter comprising a filter element according to claim 11 or 12 and, optionally, one or more separate further segments.

15. Use of a filter according to any one of claims 1 to 10 or a filter element according to claim 11 or 12 in tobacco heating products and / or HNB products and / or HTPs.

16. 3. A filter substantially as hereinbefore described with reference to either Figure 1 or Figure 2 of the drawings.

17. 1. A filter for use in an aerosol-generating article, said filter comprising: a first longitudinally extending core including a first filtering material; a second longitudinally extending core comprising a second filtering material, said second longitudinally extending core having a pressure drop of 0.1 to 1 mmWG per mm of its length, for example 0.31 to 0.7 mmWG per mm of its length, for example 0.5 to 0.6 mmWG per mm of its length, for example 0.55 mmWG per mm of its length; a wrapper engaged about the first longitudinally and second longitudinally extending core; A filter, wherein the first filtering material and the second filtering material each comprise paper and / or other biodegradable material.

18. 1. A filter element comprising a longitudinally extending core, the longitudinally extending core having a pressure drop of 0.1 to 1 mmWG per mm of length, e.g., 0.31 to 0.7 mmWG per mm of length, e.g., 0.5 to 0.6 mmWG per mm of length (e.g., a pressure drop of 0.53 to 0.57 mmWG per mm of length, e.g., a pressure drop of 0.55 mmWG per mm of length), the longitudinally extending (e.g., substantially cylindrical) core comprising a filtering material comprising paper and / or other biodegradable material (e.g., a non-cellulose acetate-containing material), and optionally a wrapper engaged around the longitudinally extending core.

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