WO2024100084A1

WO2024100084A1 - A sustainable filter and filter element

Info

Publication number: WO2024100084A1
Application number: PCT/EP2023/081083
Authority: WO
Inventors: Boby ALEXANDER; Arief RAHMAN; Agus FAHRONI; Giyanto; Moch Anis FAUZI
Original assignee: Filtrona Development Co. Pte. Ltd.; Filtrona Filters Limited
Priority date: 2022-11-09
Filing date: 2023-11-08
Publication date: 2024-05-16
Also published as: GB202216672D0

Abstract

The present invention provides 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, wherein the second longitudinally extending core has a pressure drop of from 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 comprise a paper and/or other biodegradable material and wherein the second longitudinally extending core is formed from a paper and/or other biodegradable material which is gathered laterally into rod form and held in place.

Description

A SUSTAINABLE FILTER AND FILTER ELEMENT

INTRODUCTION

The present invention provides a sustainable filter and filter element for use with an aerosol generating article such as a tobacco heating product, a heat-not-burn (HNB) product or heated tobacco product (HTP).

BACKGROUND

Tobacco heating products [heat-not-burn (HNB) product or heated tobacco product (HTP)] are well known. The idea of a tobacco heating product is that the tobacco is heated to a specific temperature (such as 350°C) without burning. This delivers a vapour containing nicotine and it is believed that heating without burning avoids creation of combustion products that are harmful to the consumer.

Tobacco heating products (HNB products or HTP) may include a plug of modified tobacco and other mouthpiece elements which are wrapped in a paper plugwrap so as to provide a cigarette-like appearance. In one such product a reconstituted tobacco plug, a wrapped hollow acetate tube, a wrapped plug of PLA [poly(lactic acid)] and a conventional wrapped acetate segment (at the mouth end) are wrapped in a white paper. In use, the product is inserted, tobacco end first, into a device which has a heating element in the form of a heating blade, such that when the product is pushed into the device the heating blade enters into the tobacco plug. The heating blade heats the tobacco so the product can then be “smoked” by the consumer who puffs at the mouth end of the product. The function of the “filter” in these products is very different from that of a cigarette filter; the main functions are to provide the look and feel of a cigarette and also to cool the vapour down to an acceptable temperature for the consumer. In the product described above it is the PLA section that performs the significant cooling function and so it may be considered a cooling element.

It is well known to use materials such as PLA for cooling elements. More recently it has become known to use cellulose acetate for cooling elements, as discussed in WO2021/074222.

However, cellulose acetate and PLA are not readily biodegradable. As a result, aerosol generating article elements such as cellulose acetate containing filter elements and cooling elements may persist in the environment for many years. Due to this, and in consideration of new Ell legislation coming into force by 2021 (aimed at reducing the use of single-use plastics such as cellulose acetate filters), there is increasing interest in filters that do not comprise single-use plastics and are readily biodegradable. Consequently, there is a need for a filter that provides acceptable cooling of the vapour in a HNB product or HTP and acceptable filtration properties while having an improved biodegradability compared to conventional materials such as cellulose acetate.

SUMMARY OF THE INVENTION

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 heated product and/or HNB product or HTP), the filter comprising: a first longitudinally extending (e.g., cylindrical) core comprising a first filtering material; 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 longitudinally extending core has a pressure drop of from 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 from 0.5 to 0.6 mmWG per mm of its length; and a wrapper (e.g. filter wrapper) engaged around the first and second longitudinally extending cores; wherein each of the first and second filtering materials comprise a paper and/or other biodegradable material (e.g. non-cellulose acetate containing material). The second longitudinally extending core has a pressure drop of from 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 from 0.5 to 0.6 mmWG per mm of its length, for example a pressure drop of from 0.53 to 0.57 mmWG per mm of its length, for example a pressure drop of 0.55 mmWG per mm of its length. Preferably the second longitudinally extending core has a pressure drop of from 0.5 to 0.6 mmWG per mm of its length, for example a pressure drop of from 0.53 to 0.57 mmWG per mm of its length, for example a pressure drop of 0.55 mmWG per mm of its length. In some examples of the invention, the first longitudinally extending core is distanced longitudinally from the second longitudinally extending core such that the wrapper defines a cavity between the first and second longitudinally extending cores.

The second longitudinally extending core has a cooling effect (e.g. on aerosol drawn through the core second longitudinally extending core and/or the filter). The first longitudinally extending core may be formed from a 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 gathered laterally into rod form and held in place (e.g. by a wrapper, e.g. by a first core wrapper). The first longitudinally extending core may be formed from a paper (e.g. uncoated paper, coated paper, siliconized paper, e.g. Puracel FM26, Puracel FM36 and/or Greenbutts) and/or other biodegradable material of width 20 mm to 350 mm, for example of width 200 mm to 350 mm, for example of width 250 to 350 mm, for example 251 to 350 mm, for example 280 to 320 mm, for example 300 mm, which is gathered laterally into rod form and held in place (e.g. by a wrapper, e.g. by a first core wrapper). It will be appreciated that the first longitudinally extending core may have a wrapper (e.g. first core wrapper) which holds the filtering material in shape (e.g. in core form, e.g. in rod or plug form). This wrapper (e.g. first core wrapper) is e.g. separate from the wrapper (e.g. filter wrapper) which is engaged around the first and second longitudinally extending cores. If there is a wrapper (e.g. first core wrapper) for the first longitudinally extending core, it will be appreciated that the wrapper (e.g. filter wrapper) engaged around the first and second longitudinally extending cores is wrapped around the wrapper (e.g. first core wrapper) of the first longitudinally extending core as well as the first longitudinally extending core itself.

The second longitudinally extending core may be formed from a paper (e.g. uncoated paper, coated paper, siliconized paper, e.g. ZNP paper) and/or other biodegradable material which is gathered laterally into rod form and held in place (e.g. by a wrapper, e.g. a second core wrapper). The second longitudinally extending core may be formed from a paper (e.g. uncoated paper, coated paper, siliconized paper, e.g. ZNP paper) and/or other biodegradable material of width 20 mm to 350 mm, for example of width 200 mm to 350 mm, for example of width 250 to 350 mm, for example 251 to 350 mm, for example 280 to 320 mm, for example 300 mm, which is gathered laterally into rod form and held in place (e.g. by a wrapper, e.g. a second core wrapper. As set out above, it is preferred that the second longitudinally extending core has a pressure drop of from 0.5 to 0.6 mmWG per mm of its length, for example a pressure drop of from 0.53 to 0.57 mmWG per mm of its length, for example a pressure drop of 0.55 mmWG per mm of its length. The density of a second longitudinally extending core which has a pressure drop of from 0.5 to 0.6 mmWG per mm of its length and is formed from 300 mm wide paper will be 0.269 g/cm³ Preferably, the density of the second longitudinally extending core is from 0.215 g/cm³ to 0.33 g/cm³, for example 0.22 g/cm³ to 0.31 g/cm³, for example 0.24 g/cm³ to 0.30 g/cm³, for example 0.25 g/cm³ to 0.29 g/cm³, for example 0.26 g/cm³ to 0.275 g/cm³, for example 0.269 g/cm³. It will be appreciated that the second longitudinally extending core may have a wrapper (e.g. second core wrapper) which holds the filtering material in shape (e.g. in core form, e.g. in rod or plug form). This wrapper (e.g. second core wrapper) is e.g. separate from the wrapper (e.g. filter wrapper) which is engaged around the first and second longitudinally extending cores. If there is a wrapper (e.g. second core wrapper) for the second longitudinally extending core, it will be appreciated that the wrapper (e.g. filter wrapper) engaged around the first and second longitudinally extending cores is wrapped around the wrapper (e.g. second core wrapper) of the second longitudinally extending core as well as the second longitudinally extending core itself.

The filter may further comprise 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), wherein the third longitudinally extending core has a pressure drop of from 0.5 to 0.6 mmWG per mm of its length. The third longitudinally extending core comprises a paper and/or other biodegradable material (e.g. non-cellulose acetate containing material). If a third longitudinally extending core is present, the wrapper (e.g. filter wrapper) is engaged around the first and second and third longitudinally extending cores. The third longitudinally extending core has a pressure drop of from 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 from 0.5 to 0.6 mmWG per mm of its length, for example a pressure drop of from 0.53 to 0.57 mmWG per mm of its length, for example a pressure drop of 0.55 mmWG per mm of its length. Preferably the third longitudinally extending core has a pressure drop of from 0.5 to 0.6 mmWG per mm of its length, for example a pressure drop of from 0.53 to 0.57 mmWG per mm of its length, for example a pressure drop of 0.55 mmWG per mm of its 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 a paper (e.g. uncoated paper, coated paper, siliconized paper, e.g. ZNP paper) and/or other biodegradable material which is gathered laterally into rod form and held in place (e.g. by a wrapper, e.g. a third core wrapper). The third longitudinally extending core may be formed from a paper (e.g. uncoated paper, coated paper, siliconized paper, e.g. ZNP paper) and/or other biodegradable material of width 250 to 350 mm, for example 251 to 350 mm, for example 280 to 320 mm, for example 300 mm, which is gathered laterally into rod form and held in place (e.g. by a wrapper, e.g. a third core wrapper). It will be appreciated that the third longitudinally extending core may have a wrapper (e.g. third core wrapper) which holds the filtering material in shape (e.g. in core form, e.g. in rod or plug form). This wrapper (e.g. third core wrapper) is e.g. separate from the wrapper (e.g. filter wrapper) which is engaged around the first and second (and third) longitudinally extending cores. If there is a wrapper (e.g. third core wrapper) for the third longitudinally extending core, it will be appreciated that the wrapper (e.g. filter wrapper) engaged around the first and second (and third) longitudinally extending cores is wrapped around the wrapper (e.g. third core wrapper) of the third longitudinally extending core as well as the third longitudinally extending core itself.

The applicants have surprisingly found that filters according to aspects the invention combine biodegradilbility (are “readily biodegradeable”) with a comparable thermal profile and/or comparable Aerosol Chemistry Delivery to the product in the market which uses cellulose acetate and PLA. Further the applicants have found the filters of the invention are adaptable to provide a customizable design to match a desired aerosol chemistry delivery profile.

The first filtering material may comprise a paper and/or other biodegradable material which is readily biodegradable. The second filtering material may comprise a paper and/or other biodegradable material which is readily biodegradable. Preferably, each of the first and second filtering materials comprise a paper and/or other biodegradable material which is readily biodegradable.

The term “biodegradable” as used herein refers to the filtering material and filter being able to exhibit a biodegradation of at least 90% 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).

Preferably, the paper and/or other biodegradable material (e.g. non-cellulose acetate containing material) used in the filtering material(s) of the filter of the present invention is “readily biodegradable” and has an enhanced biodegradability compared to cellulose acetate. Therefore, the present invention provides a filter of enhanced biodegradability, and thus is more environmentally friendly and is more in line with Ell legislation.

The phrase “readily biodegradable” as used herein refers to the filtering material and filter being able to disintegrate rapidly and completely biodegrade when immersed in water. Preferably the filter (and filtering materials used therein) has the ‘Ready Biodegradability’ level of biodegradability as measured according to OECD 301 B ‘Ready Biodegradability’ method (modified Sturm test), which is well known in the art. The phase “readily biodegradable” will here be understood to mean ‘Ready Biodegradability’ level of biodegradability.

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) may be comprised of any paper (in any form) which is conventionally used in filters or filter elements. The paper may be, for example, filtering paper, aperture paper, crepe paper, air-laid paper or machine glazed paper etc. of varying grades. The fibre of the paper and/or other biodegradable material (e.g. non- cellulose acetate containing filtering material) may be a natural fibre (e.g. flax, hemp, sisal, jute, abaca, cotton, coconut fibres, bamboo fibres, starch (e.g. from corn), or tobacco) or any roll material. The paper may be woven or non-woven, or in the form of a coherent web of paper, or a longitudinally corrugated and/or fibrillated web of paper e.g. gathered laterally into, and held, in plug form. 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 a similar structure to those papers sold under the trademark Myria® or Puracel® (of Essentra pic).

The first filtering material may comprise a paper and/or other biodegradable material which is readily biodegradable. The first filtering material may comprise a paper and/or other biodegradable material as set out in the paragraph above. In some examples, the first filtering material comprises Puracel FM26, Puracel FM36 and/or Greenbutts.

The second filtering material may comprise a paper and/or other biodegradable material which is readily biodegradable. The second filtering material may comprise a paper and/or other biodegradable material as described above. In some examples, the second filtering material comprises Uncoated Paper, Coated Paper and/or Siliconized Paper.

The third filtering material may comprise a paper and/or other biodegradable material which is readily biodegradable. The third filtering material may comprise a paper and/or other biodegradable material as described above. In some examples, the third filtering material comprises Uncoated Paper, Coated Paper and/or Siliconized Paper.

Preferably, the first filtering material comprises a paper having a basis weight from 20 gsm to 200 gsm. For example, the first filtering material may be a paper having a basis weight from 40 gsm to 180 gsm, e.g. from 60 gsm to 160 gsm, e.g. from 80 gsm to 140 gsm, e.g. from 100 gsm to 120 gsm, e.g. from 20 gsm to 60 gsm, e.g. from 30 gsm to 40 gsm.

Preferably, the second filtering material comprises a paper having a basis weight from 20 gsm to 200 gsm. For example, the second filtering material may be a paper having a basis weight from 40 gsm to 180 gsm, e.g. from 60 gsm to 160 gsm, e.g. from 80 gsm to 140 gsm, e.g. from 100 gsm to 120 gsm, e.g. from 20 gsm to 60 gsm, e.g. from 30 gsm to 40 gsm.

Preferably, the third filtering material comprises a paper having a basis weight from 20 gsm to 200 gsm. For example, the third filtering material may be a paper having a basis weight from 40 gsm to 180 gsm, e.g. from 60 gsm to 160 gsm, e.g. from 80 gsm to 140 gsm, e.g. from 100 gsm to 120 gsm, e.g. from 20 gsm to 60 gsm, e.g. from 30 gsm to 40 gsm.

The filter of the invention may be cylindrical. The filter of the invention may be cylindrical with circumference from 12 to 30 mm (e.g., 15 to 28 mm), more preferably from 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).

The wrapper (e.g. filter wrapper) engaged around the first and second (and optionally, third) longitudinally extending cores may be a paper (e.g., plugwrap), preferably a paper (e.g., plugwrap) of basis weight 20 to 160 gsm, for example a paper (e.g., plugwrap) of basis weight 24 to 150 gsm, for example a paper (e.g., plugwrap) of basis weight 70 to 150 gsm, for example a paper (e.g., plugwrap) of basis weight 70 to 140 gsm. Preferably the wrapper (e.g. filter wrapper) engaged around the first and second (and optionally, third) longitudinally extending cores is biodegradable, more preferably readily biodegradable.

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 a paper (e.g., plugwrap). The paper may be a paper (e.g., plugwrap) of basis weight 20 to 160 gsm, for example a paper (e.g., plugwrap) of basis weight 24 to 150 gsm, for example a paper (e.g., plugwrap) of basis weight 70 to 150 gsm, for example a paper (e.g., plugwrap) of basis weight 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, is 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.

The wrapper for the third longitudinally extending core (e.g. third core wrapper) may be a paper (e.g., plugwrap). The paper may be a paper (e.g., plugwrap) of basis weight 20 to 160 gsm, for example a paper (e.g., plugwrap) of basis weight 24 to 150 gsm, for example a paper (e.g., plugwrap) of basis weight 70 to 150 gsm, for example a paper (e.g., plugwrap) of basis weight 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.

The filter of the invention may be of length 18 mm to 60mm, for example 20 to 50 mm (e.g., from 20 to 35mm). Preferably, the filter of the invention is of length 30 to 35 mm, for example 31 mm to 34 mm, for example 33 mm.

The first longitudinally extending core may be of length 3 to 18mm, for example of length 3 to 11 mm, for example 6 to 10 mm, for example 6, 7, 8, 9 or 10 mm.

The second longitudinally extending core may be of length 7 to 30 mm, for example 17 to 25 mm, for example 18 to 24mm, for example, 18, 19, 20, 21 , 22, 23 or 24 mm.

The third longitudinally extending core, if present, may be of length 3 to 18mm, for example of length 3 to 11 mm, for example 6 to 10 mm, for example 6, 7, 8, 9 or 10 mm.

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

Preferably the filter has pressure drop (longitudinally along the length of the whole filter) of 10 to 50 mmWG, for example 23 to 35 mmWG, for example 24 to 31 mmWG, for example 28 to 31 mm WG. In one example, the filter of the invention is of length 33 mm and comprises a first longitudinally extending core of length 10 mm; a second longitudinally extending core of length 18 mm; and a cavity between the first and second longitudinally extending cores of length 5 mm. This example is illustrated in attached Figure 1.

In another example, the filter of the invention is of length 33 mm and comprises a first longitudinally extending core of length 8 mm; a second longitudinally extending core of length 18 mm; and a cavity between the first and second longitudinally extending cores of length 7 mm.

In a further example, the filter of the invention is of length 33 mm and comprises a first longitudinally extending core of length 6 mm; a second longitudinally extending core of length 18 mm; and a cavity between the first and second longitudinally extending cores of length 9 mm.

In a still further example, the filter of the invention is of length 33 mm and comprises a first longitudinally extending core of length 9 mm abutted to a second longitudinally extending core of length 24 mm. In this example there is no cavity between the first and second longitudinally extending cores. This example is illustrated in attached Figure 2.

In a further example, the filter of the invention is of length 33 mm and comprises a first longitudinally extending core of length 8 mm; a second longitudinally extending core of length 18 mm; and a third longitudinally extending core of length 7mm between the first and second longitudinally extending cores. In this example there is no cavity between the first and second longitudinally extending cores.

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 wanting to be bound by theory, it is thought that the hydrophobic material within the filtering material causes water vapour within the element (e.g. cooling element) to condense within the element (e.g. cooling element) which provides the beneficial effect of cooling the vapour as it passes through the element. Preferably, the hydrophobic material is distributed throughout the longitudinally extending (e.g., cylindrical) core(s). The applicants have found that this provides an optimal level of vapour cooling and filtration for use in a tobacco heating product or HNB product. The hydrophobic coati ng/material may be any suitable hydrophobic material. For example, the hydrophobic coating/material may a polymer or a blend of polymers. Preferably, the hydrophobic coating/material is a starch, such as a modified starch, for example oxidized starch (E1404). A starch such as a modified starch is preferred as it is inert and provides a non-plastic hydrophobic coating. The hydrophobic coating/material may be present in an amount from 0.01 % to 50 % weight of hydrophobic coating/material with respect to weight of the relevant longitudinally extending core (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. 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.

Preferably the filter has a substantially circular cross section meaning the element is substantially cylindrical in shape. However, the filter of the present invention may be any shape. For example, the filter may have an annular cross section or an oval cross section or a square cross section or a rectangular cross section.

It will be appreciated that the filter of the invention may be used in any multi-segment filter or consumable. The multi-segment filter may comprise one, two, three, four or more additional discrete segments. The additional discrete further segments may be (e.g., cylindrical) plugs of tobacco smoke filtering material (e.g., paper) and/or a hollow (e.g., paper) tube filter. 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 include other filter segments that include capsule containing filters, carbon containing filters, CPS filters, tube filters, paper filters, menthol containing filters etc.

According to the present invention in a further aspect there is provided a (e.g. biodegradable, e.g. readily biodegradable) filter element comprising a longitudinally extending (e.g. substantially cylindrical) core having a pressure drop of from 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 from 0.5 to 0.6 mmWG per mm of its length (for example a pressure drop of from 0.53 to 0.57 mmWG per mm of its length, for example a pressure drop of 0.55 mmWG per mm of its length); the longitudinally extending (e.g. substantially cylindrical) core comprising a filtering material comprising a paper and/or other biodegradable material (e.g. non-cellulose acetate containing material). The filter element may have a wrapper (e.g. a core wrapper), e.g. a paper wrapper, e.g. a paper wrapper which is biodegradable and/or readily biodegradeable, engaged around the longitudinally extending core. The longitudinally extending core may be formed from a paper (e.g. uncoated paper, coated paper, siliconized paper, e.g. ZNP paper) and/or other biodegradable material which is gathered laterally into rod form and held in place (e.g. by the wrapper, e.g. core wrapper). The longitudinally extending core may be formed from a paper (e.g. uncoated paper, coated paper, siliconized paper, e.g. ZNP paper) and/or other biodegradable material of width 250 to 350 mm, for example 251 to 350 mm, for example 280 to 320 mm, for example 300 mm, which is gathered laterally into rod form and held in place (e.g. by the wrapper, e.g. core wrapper). Preferably the longitudinally extending (e.g. substantially cylindrical) core has a pressure drop of from 0.5 to 0.6 mmWG per mm of its length, for example a pressure drop of from 0.53 to 0.57 mmWG per mm of its length, for example a pressure drop of 0.55 mmWG per mm of its length. Preferably, the longitudinally extending (e.g. substantially cylindrical) core has a density of from rom 0.215 g/cm³ to 0.33 g/cm³, for example 0.22 g/cm³ to 0.31 g/cm³, for example 0.24 g/cm³ to 0.30 g/cm³, for example 0.25 g/cm³ to 0.29 g/cm³, for example 0.26 g/cm³ to 0.275 g/cm³, for example 0.269 g/cm³. .

The filter element has a cooling effect (e.g. on aerosol drawn through the longitudinally extending core and/or any filter including the filter element). It will be appreciated that the term “element” or “filter element” as used herein refers to any discrete segment that can be used in a filter or aerosol generating article. The element may be a cooling element. It will be appreciated that the term “cooling element” as used herein refers to a discrete segment which provides a significant cooling function i.e., lowering the temperature of aerosol or vapour as it passes along the length of the element.

The term “biodegradable” as used herein refers to the filtering material and filter element being able to exhibit a biodegradation of at least 90% 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). Preferably, the paper and/or other biodegradable material (e.g. non-cellulose acetate containing material) used in the filtering material of the (filter) element of the present invention is “readily biodegradable” and has an enhanced biodegradability compared to cellulose acetate. Therefore, the present invention provides a filter element of enhanced biodegradability, and thus is more environmentally friendly and is more in line with Ell legislation. The phrase “readily biodegradable” as used herein refers to the filtering material and element being able to disintegrate rapidly and completely biodegrade when immersed in water. Preferably the element has the ‘Ready Biodegradability’ level of biodegradability as measured according to OECD 301 B ‘Ready Biodegradability’ method (modified Sturm test), which is well known in the art. The phase “readily biodegradable” will here be understood to mean ‘Ready Biodegradability’ level of biodegradability.

The filtering material may comprise a paper and/or other biodegradable material which is readily biodegradable. The filtering material may comprise a paper and/or other biodegradable material described above. In some examples, the filtering material comprises Uncoated Paper, Coated Paper and/or Siliconized Paper. Preferably, the filtering material comprises a paper having a basis weight from 20 gsm to 200 gsm. For example, the filtering material may be a paper having a basis weight from 40 gsm to 180 gsm, e.g. from 60 gsm to 160 gsm, e.g. from 80 gsm to 140 gsm, e.g. from 100 gsm to 120 gsm, e.g. from 20 gsm to 60 gsm, e.g. from 30 gsm to 40 gsm. The filter element of the invention may be cylindrical. The filter element of the invention may be cylindrical with circumference from 12 to 30 mm (e.g., 15 to 28 mm), more preferably from 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).

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

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

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

It will be appreciated that the filter element of the invention may be used in any multi-segment filter or consumable. The filter construction could be two, three, four or more discrete segments. The discrete further segments may be (e.g., cylindrical) plugs of tobacco smoke filtering material (e.g., paper) and/or a hollow (e.g., paper) tube filter. 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 include other filter segments that include capsule containing filters, carbon containing filters, CPS filters, tube filters, paper filters, menthol containing filters etc.

It will be appreciated that filters or filter elements according to the invention may be manufactured by methods and machinery well known in the art.

According to the present invention in a further aspect there is provided a aerosol generating article (e.g. cigarette, e.g. tobacco heat product, HNB product) comprising a filter or filter element according to any aspect of the invention.

The filter or filter element of the present invention is suitable for use with all varieties of tobacco blends. In a aerosol generating article according to the invention, a filter of the invention (or a filter which includes a filter element of the invention) may be joined to a wrapped plug of tobacco (e.g. wrapped plug of modified tobacco, as is well known in the art). The filter of the invention (or filter which includes a filter element of the invention) may be joined to the wrapped tobacco plug such that the (second) longitudinally extending core which has a pressure drop of from 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 from 0.5 to 0.6 mmWG per mm (e.g. 0.55 mmHG per mm) of its length is adjacent 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) which engages around just the adjacent ends of the wrapped filter and the tobacco plug to leave much of the filter wrap exposed). The filter may be joined to the wrapped tobacco plug by a full tipping overwrap (i.e. an outer wrapper (e.g. tipping paper) which engages around the full wrapped filter length and the adjacent end of the tobacco plug). The wrapper (e.g. filter wrapper) may be ventilated by e.g. laser perforations. The ventilation may be applied to the wrapper (e.g. filter wrapper) before or after the filter is joined to the wrapped tobacco plug. The ventilation may be (applied to the wrapper) in register with the cavity in the filter (if present).

The tobacco heating product and/or HNB product or HTP according to the present invention may further comprise one or more discrete further segments (e.g., of a HNB mouthpiece). The discrete further segments may be (e.g., cylindrical) plugs of tobacco smoke filtering material (e.g., paper), a (e.g., cylindrical) rod of tobacco (e.g., any form of tobacco (including reconstituted tobacco)), hollow (e.g., paper) tubes, capsule containing filters, carbon containing filters, CPS filters, tube filters, acetate filters, paper filters, menthol containing filters etc.

The present invention will now be described in further detail by reference to the attached Figures in which:

Figure 1 shows a perspective view, part cut away, of a filter according to one embodiment of the invention which includes a filter element according to a further embodiment of the invention;

Figure 2 shows a perspective view, part cut away, of a filter according to a further embodiment of the invention (different to that of figure 1) which includes a filter element according to a still further embodiment of the invention; Figure 3 is a graphical representation of how the temperature at the mouth end of HTPs including filters and filter elements according to the invention (Examples SAM111426- IQ- 150, SAM111426-8-150 and SAM111426-6-150) and the reference product Amber HEETS varies as puffs are taken (see Example 1).

Figure 1 illustrates a perspective view, part cut away, of a filter 1 for use in a aerosol generating article (e.g., a tobacco heated product and/or HNB product and/or HTP). Filter 1 is cylindrical in shape with length 33 mm and circumference 22.45 mm.

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

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

A further filter wrapper 11 of stiff plug wrap of 78 g/m² weight [from Mudanjiang Hengfeng Paper Co., Ltd of Mundanjiang, China] is engaged around the wrapped longitudinally extending cores 3 and 7 to define a cavity 13 of length 5 mm between the wrapped longitudinally extending cores 3 and 7. Both ends of the further wrapper 11 are flush with the ends of wrapped cores 3 and 7. The filter wrapper 11 has an overlapping longitudinal edge with adhesive applied thereon which provides a lapped and stuck seam (not shown) holding the further wrapper 11 around the wrapped cores 3 and 7 and a further adhesive in anchor lines (not shown) in register with the wrapped cores 3 and 7 to hold the cores in place. The first and second longitudinally extending cores 3 and 7, their respective first core wrapper 5 and second core wrapper 9, and the filter wrapper 11 , are all made of paper material and are all “readily biodegradeable”, meaning they are able to disintegrate rapidly and completely biodegrade when immersed in water, such that filter 1 (and materials therein) have the ‘Ready Biodegradability’ level of biodegradability as measured according to OECD 301 B ‘Ready Biodegradability’ method (modified Sturm test), which is well known in the art.

The applicants have surprisingly found that filters such as filter 1 combine biodegradilbility (are “readily biodegradeable”) with a comparable thermal profile and/or comparable Aerosol Chemistry Delivery to the product in the market which uses cellulose acetate and PLA (see Example 1 below). Further the applicants have found the filters of the invention are adaptable to provide a customizable design to match a desired aerosol chemistry delivery profile.

It will be appreciated that the filter 1 may be made by methods known in the art and may be prepared as a multiple rod comprising a plurality (e.g. 2, 4, 6 etc.) of filters or filter rods integrally joined end-to-end.

The filter 1 may be joined, at the end opposite to mouth end 2, to a wrapped plug of modified tobacco, by methods well known in the art. A suitable plug of reconstituted tobacco is 12 mm long and has a circumference of 22 mm. Such plugs of reconstituted tobacco are well known in the art. Together the filter and plug of tobacco form a HNB product or HTP including filter of the invention 1.

In use, the tobacco plug end of a HNB product or HTP including filter of the invention 1 is inserted in a HTP device. This plug is heated in use by a heating device (HTP device) to produce a vapour, as is well known in the art. This produces a hot vapour which is first drawn 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). It is believed that drawing this hot vapour through the second longitudinally extending core 7 of pressure drop 0.55 mmWG per mm of its length has a cooling effect (e.g. on aerosol drawn through the second longitudinally extending core and/or the filter) which cools the vapour down to a temperature that is acceptable for the user.

Figure 2 illustrates a schematic view of a further embodiment of the invention. Figure 2 shows filter 101 for use in a aerosol generating article (e.g., a tobacco heated product and/or HNB product and/or HTP). Filter 101 is cylindrical in shape with length 33 mm and circumference 22.45 mm.

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

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

A further filter wrapper 111 of stiff plug wrap of 78 g/m² weight [from Mudanjiang Hengfeng Paper Co., Ltd of Mundanjiang, China] is engaged around the wrapped cores 103 and 107. Both ends of the further wrapper 111 are flush with the ends of wrapped cores 103 and 107. The further wrapper 111 has an overlapping longitudinal edge with adhesive applied thereon which provides a lapped and stuck seam (not shown) holding the further wrapper 111 around the wrapped cores 103 and 107 and a further adhesive in anchor lines (not shown) in register with the wrapped cores 103 and 107 to hold the cores in place.

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 material and are all “readily biodegradeable”, meaning they are able to disintegrate rapidly and completely biodegrade when immersed in water, such that filter 101 (and materials therein) have the ‘Ready Biodegradability’ level of biodegradability as measured according to OECD 301 B ‘Ready Biodegradability’ method (modified Sturm test), which is well known in the art. The applicants have surprisingly found that filters such as filter 101 combine biodegradilbility (are “readily biodegradeable”) with a comparable thermal profile and/or comparable Aerosol Chemistry Delivery to the product in the market which uses cellulose acetate and PLA. Further the applicants have found the filters of the invention are adaptable to provide a customizable design to match a desired aerosol chemistry delivery profile.

Example 1 - Experiment

A filter according to the invention as illustrated with reference to Figure 1 of length 33 mm including a first longitudinally extending core of length 10 mm (FM26 paper); a second longitudinally extending core of length 18 mm (ZNP paper); and a cavity between the first and second longitudinally extending cores of length 5 mm, was attached to a plug of reconstituted tobacco by methods well known in the art to provide a HNB product or HTP for testing. This is referred to as test Example SAM111426-10-150 (abbreviated to SAM426- 10-150).

Similarly, a second filter according to the invention of length 33 mm including a first longitudinally extending core of length 8 mm (FM26 paper); a second longitudinally extending core of length 18 mm (ZNP paper); and a cavity between the first and second longitudinally extending cores of length 7 mm, was attached to a plug of reconstituted tobacco by methods well known in the art to provide a HNB product or HTP for testing. This is referred to as test Example SAM111426-8-150 (abbreviated to SAM426-8-150).

A third filter according to the invention of length 33 mm including a first longitudinally extending core of length 6 mm (FM26 paper); a second longitudinally extending core of length 18 mm (ZNP paper); and a cavity between the first and second longitudinally extending cores of length 9 mm, was attached to a plug of reconstituted tobacco by methods well known in the art to provide a HNB product or HTP for testing. This is referred to as test Example SAM111426-6-150 (abbreviated to SAM 426-6- 150).

The reference product Amber HEETS includes a plug of reconstituted tobacco, and a 3mm long filter including a hollow acetate tube of length 7 mm (tobacco end), a PLA cooling element of length 18 mm, herein referred to as a “conventional cooling element”, and a mouth end cylindrical plug of cellulose acetate tow of length 8mm, in an analogous arrangement to that shown in Figure 1. The HNB test Examples SAM111426-10-150, SAM111426-8-150 and SAM111426-6-150 and the reference Amber HEETS were compared as follows.

Each product was inserted into a heating device. The mouth end of the product was inserted into a smoking machine which is configured to smoke the product. An IR camera was used to analyse the temperature at the mouth end of the product while it was being smoked. The smoking machine was configured to take a puff on the product every 30 seconds, each puff being 2 seconds long. The temperature at the mouth end of the product was measured for each puff. The experiment was performed 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.

Figures 3 is a graphical representation of how the temperature at the mouth end of HNB products/THP including filters and filter elements according to the invention (Examples SAM111426-10-150, SAM 111426-8-150 and SAM 111426-6-150) and the reference product Amber HEETS varies as puffs are taken. Figure shows that paper based filters of the present invention are capable of providing a cooling effect that is equivalent to conventional cooling elements, while providing the huge benefit of being readily biodegradable.

The temperature change, nicotine and aerosol collected mass yields of the products SAM111426-10-150 and SAM111426-6-150 (each including a filter according to the 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 illustrated in Table 1.

Table 1

*This is hotter than reference but acceptable because it is less than 5% hotter than the reference. Table 1 (and Fig 3) shows that filters and elements according to the present invention may provide comparable thermal profile and/or comparable Aerosol Chemistry Delivery performance to conventional cooling elements (the reference), while also providing improved biodegradability (because they do not contain e.g. PLA elements).

Claims

1 . A filter for use in an aerosol generating article, the filter comprising: a first longitudinally extending core comprising a first filtering material; a second longitudinally extending core comprising a second filtering material, wherein the second longitudinally extending core has a pressure drop of from 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; and a wrapper engaged around the first and second longitudinally extending cores; wherein each of the first and second filtering materials comprise a paper and/or other biodegradable material; and wherein the second longitudinally extending core is formed from a paper and/or other biodegradable material which is gathered laterally into rod form and held in place (e.g. by a wrapper).

2. A filter according to claim 1 wherein the second longitudinally extending core has a cooling effect on aerosol drawn through the core.

3. A filter according to claim 1 or claim 2 wherein the first longitudinally extending core is distanced longitudinally from the second longitudinally extending core such that the wrapper defines a cavity between the first and second longitudinally extending cores.

4. A filter according to any preceding claim wherein the second longitudinally extending core is formed from a paper and/or other biodegradable material of width of width 20 mm to 350 mm, for example of width 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 which is gathered laterally into rod form and held in place (e.g. by a wrapper).

5. A filter according to any preceding claim wherein each of the first and second filtering materials comprise a paper and/or other biodegradable material which is readily biodegradable. A filter according to any preceding claim wherein the filter is cylindrical with circumference from 12 to 30 mm (e.g., 15 to 28 mm), more preferably from 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). A filter according to any preceding claim of length 18 to 60 mm, for example 30 to 35 mm, for example 33 mm. A filter according to any preceding claim wherein the first longitudinally extending core is of length 3 to 18mm, for example 3 to 11 mm, for example 6 to 10 mm. A filter according to any preceding claim wherein the second longitudinally extending core is of length 7 to 30 mm, for example 17 to 25 mm, for example 18 to 24mm. A filter according to any preceding claim which includes a cavity between the first and second longitudinally extending cores, wherein the cavity is of length 3 to 18mm, for example length 4 to 10 mm, for example 5 to 9 mm. A filter element comprising a longitudinally extending core having a pressure drop of from 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 from 0.5 to 0.6 mmWG per mm of its length (for example a pressure drop of from 0.53 to 0.57 mmWG per mm of its length, for example a pressure drop of 0.55 mmWG per mm of its length); the longitudinally extending (e.g. substantially cylindrical) core comprising a filtering material comprising a paper and/or other biodegradable material (e.g. non-cellulose acetate containing material) and a wrapper engaged around the longitudinally extending core; wherein the longitudinally extending core is formed from a paper and/or other biodegradable material which is gathered laterally into rod form and held in place by the wrapper. A filter element according to claim 11 wherein the longitudinally extending core is formed from a paper and/or other biodegradable material of width 20 mm to 350 mm, for example of width 200 mm to 350 mm, for example of width 250 to 350 mm, for example 251 to 350 mm, for example 280 to 320 mm, for example 300 mm, which is gathered laterally into rod form and held in place (e.g. by the wrapper). A aerosol generating article (e.g., tobacco heating product, HNB product) comprising a filter according to any of claims 1 to 10 or comprising a filter comprising a filter element according to any of claims 11 to 12 and optionally one or more discrete further segments. A tobacco heating product and/or HNB product and/or HTP comprising a filter according to any of claims 1 to 10 or comprising a filter comprising a filter element according to any of claims 11 to 12 and optionally one or more discrete further segments.. The use, in a tobacco heated product and/or HNB product and/or HTP, of a filter according to any of claims 1 to 10 or a filter element according to any of claims 11 to 12. A filter substantially as hereinbefore described with reference to either Figure 1 or Figure 2 of the drawings. A filter for use in an aerosol generating article, the filter comprising: a first longitudinally extending core comprising a first filtering material; a second longitudinally extending core comprising a second filtering material, wherein the second longitudinally extending core has a pressure drop of from 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; and a wrapper engaged around the first and second longitudinally extending cores; wherein each of the first and second filtering materials comprise a paper and/or other biodegradable material. A filter element comprising a longitudinally extending core having a pressure drop of from 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 from 0.5 to 0.6 mmWG per mm of its length (for example a pressure drop of from 0.53 to 0.57 mmWG per mm of its length, for example a pressure drop of 0.55 mmWG per mm of its length); the longitudinally extending (e.g. substantially cylindrical) core comprising a filtering material comprising a paper and/or other biodegradable material (e.g. non-cellulose acetate containing material) and optionally a wrapper engaged around the longitudinally extending core.