A water dispersible filter

Abstract

There is provided a filter for an aerosol generation consumable, the filter comprising: a segment comprising a water dispersible material; and a water dispersible wrapper at least partly surrounding the segment, wherein a base weight of the water dispersible material is higher than a base weight of the water dispersible wrapper.

Description

[0001] A Water Dispersible Filter

[0002] The present disclosure relates to a filter for an aerosol generation consumable and a consumable comprising the filter.

[0003] Background

[0004] Aerosol generation consumables, such as conventional cigarettes and consumables designed for non-combustion heating type devices typically comprise filters. The most common filters are made of acetate tow. However, acetate tow is biodegradable only in certain specific conditions not easily met in natural environment, and does not disperse in liquids, such as water. Therefore, known filters being made from acetate tow take a very long time, many years in practice, to break down naturally when left over in nature.

[0005] It is the object of the invention to overcome at least some of the above referenced problems.

[0006] Summary

[0007] According to the present disclosure there is provided a filter for an aerosol generation consumable, the filter comprising: a segment comprising a water dispersible material; and a water dispersible wrapper at least partly surrounding the segment, wherein a base weight of the water dispersible material is equal to or higher than a base weight of the water dispersible wrapper.

[0008] Advantageously, the filter comprising a water dispersible material and a water dispersible wrapper allows the filter to have a higher dispersibility in water and therefore be more environmentally friendly. Furthermore, a base weight of the water dispersible material being equal to or higher than a base weight of the water dispersible wrapper provides a filter with an improved dispersibility.

[0009] In one example, a base weight of the water dispersible material is higher than a base weight of the water dispersible wrapper. Advantageously, a base weight of the water dispersible material being higher than a base weight of the water dispersible wrapper provides a filter with an improved dispersibility. The water dispersible material may comprise cellulose fibres. Advantageously, cellulose fibres have good dispersibility in water. For example, the water dispersible material may be paper. The water dispersible material being formed from paper provides the wrapper with good dispersibility.

[0010] The water dispersible material may comprise a binding agent. Advantageously, the binding agent binds the fibres of the water dispersible material together to maintain its shape whilst also dissolving in water to allow the water dispersible material to disperse in water.

[0011] The water dispersible wrapper may be a paper wrapper. The wrapper being formed from paper provides the wrapper with good dispersibility.

[0012] The total dry weight of the water dispersible material and the water dispersible wrapper may be less than 0.25g. Advantageously, the total dry weight of the water dispersible material and the water dispersible wrapper being less than 0.25g provides a filter with improved water dispersibility.

[0013] The base weight of the water dispersible material may be from 30 to 50 g / m2. Advantageously, the base weight of the water dispersible material being from 30 to 50 g / m2improves the water dispersibility of the water dispersible material.

[0014] The base weight of the water dispersible wrapper may be from 25 to 45 g / m2. Advantageously, the base weight of the water dispersible wrapper being from 25 to 45 g / m2improves the water dispersibility of the water dispersible wrapper.

[0015] The porosity of the water dispersible material may be at least 3500 CU. The water dispersible material having a porosity of at least 3500 CU provides a filter with good dispersibility.

[0016] The porosity of the water dispersible material may be less than the porosity of the water dispersible wrapper. Advantageously, the porosity of the water dispersible material being less than the porosity of the water dispersible wrapper provides a filter with good dispersibility. The water dispersibility rate of the water dispersible material may be less than the water dispersibility rate of the water dispersible wrapper. In this example, the water dispersible wrapper is dispersed at a faster rate compared with the water dispersible material. After the water dispersible wrapper is dispersed, the filter cannot hold its shape (for example, the rod shape), and so at this stage the water dispersible material may become more dispersible.

[0017] The filter may have a water dispersibility rate of at least 50%. The filter being water dispersible means that it is less harmful to the environment.

[0018] The water dispersible material may have a creped structure. The creped structure provides the water dispersible material with a hardness which allows it to maintain its shape and function as a filter.

[0019] The filter may have a hardness of less than 85%. Advantageously, the hardness being less than 85% provides a filter which has improved dispersibility.

[0020] According to the present disclosure there is provided an aerosol generation consumable comprising: an aerosol generation precursor material wrapped with wrapping paper; a filter according to the present disclosure; and tipping paper connecting the aerosol generation precursor material and the filter.

[0021] The above referenced features may be combined in various combinations.

[0022] Brief Description of the Drawings

[0023] Examples of the present disclosure will now be described with reference to the accompanying drawings.

[0024] Figure 1 shows a schematic view of an aerosol generation consumable comprising a filter with a portion exposed to show the internal construction;

[0025] Figure 2 shows a schematic cross section of a filter in an undeformed state and a deformed state; and Figure 3 shows a perspective view of the aerosol generation consumable of Figure 1 , with further optional components shown.

[0026] Detailed Description

[0027] As used herein, the term “aerosol precursor material”, “vapour precursor material” or “vaporizable material” are used synonymously and may refer to a material and / or composition, which may for example comprise nicotine or tobacco and, optionally, a vaporising agent. The aerosol precursor material is configured to release an aerosol when combusted, heated or otherwise mechanically stimulated (such as by vibrations). Tobacco may take the form of various materials such as shredded tobacco, granulated tobacco, tobacco leaf and / or reconstituted tobacco. Nicotine may be in the form of nicotine salts. Suitable vaporising agents include: a polyol such as sorbitol, glycerol, and glycols like propylene glycol or triethylene glycol; a non-polyol such as monohydric alcohols, acids such as lactic acid, glycerol derivatives, esters such as triacetin, triethylene glycol diacetate, triethyl citrate, glycerin or vegetable glycerin. In some examples, the aerosol precursor material is substantially a liquid or a gel that holds or comprises one or more solid particles, such as tobacco particles extracted from tobacco materials or suspended in a solution or gel.

[0028] As used herein, the term “aerosol” may include a suspension of vaporizable material as one or more of: solid particles; liquid droplets; gas. Said suspension may be in a gas including air. Aerosol herein may generally refer to / include a vapour. Aerosol may include one or more components of the vaporizable material.

[0029] As used herein, the term “water dispersible” refers to a component formed of a material that physically breaks down or disintegrates when the material comes into contact with water. A “water dispersible material” and a “water dispersible wrapper” is considered to be “water dispersible” if it has a dispersibility of at least 30%, such as 40%, as measured by the procedure discussed below. A “filter” is considered to be “water dispersible” if it has a dispersibility of at least 20%, such as 30%, as measured by the procedure discussed below.

[0030] As used herein, “g / m2” means grams per metre squared and may be used interchangeably with “grams per square metre (gsm)”. An embodiment of a filter 100 for an aerosol generation consumable according to the present invention is shown in Figure 1.

[0031] The filter 100 comprises a segment comprising a water dispersible material 102 and a water dispersible wrapper 104. The water dispersible wrapper 104 is at least partially surrounding the segment comprising a water dispersible material 102. In one example, the water dispersible wrapper 104 is fully surrounding the segment comprising a water dispersible material 102, as shown in Figure 1.

[0032] The water dispersible material 102 may comprise any suitable fibres. For example, the water dispersible material may comprise fibres selected from wood pulp fibres such as soft-wood kraft pulp, hard-wood kraft pulp or dissolving pulp, and non-wood plant fibres such as kenaf pulp, flax pulp or linter pulp. In one example, the water dispersible material 102 is formed from cellulose fibres. For example, the water dispersible material 102 may comprise cellulose fibres such as paper and / or non-woven fabric. In some examples, the water dispersible material 102 only comprises pulp fibres. That is that it does not contain chemical cellulose fibres and / or plastic fibres.

[0033] The water dispersible material may also comprise a binding agent. The binding agent may be selected from any suitable water-soluble binding agent. The water-soluble binding agent may be impregnated into components of the water dispersible material 102 and filled at least partially in the voids between the fibres of the water dispersible material 102.

[0034] In one example, the water-soluble binding agent may be selected from carboxyalkyl cellulose salt, alginic acid salt, pectic acid salt, polyacrylic acid salt, polymethacrylic acid salt, carboxyalkylated starch, phosphate esterified starch, anionic polyacrylamide, or other anionic polymer electrolyte salt, methyl cellulose, hydroxyalkyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, polyalkylene oxide, polyvinyl alkyl ether, hydroxyalkylated starch, oxidized starch, pregelatinized starch, or other polymer nonelectrolyte, guar gum, trant gum, xanthan gum, gum arabic, carrageenan, galactomannan, pullulan, dextran, dextrin, or other water-soluble polysaccharide, gelatin, casein, or other water-soluble protein, etc., of which one type may be used alone or two or more types may be combined. In one example, the water-soluble binding agent may be selected from carboxymethyl cellulose salt and / or carboxyethyl cellulose salt.

[0035] Preferably, the water dispersible material 102 comprises cellulosic fibres and a water- soluble binding agent.

[0036] In one example, the water dispersible material 102 has a creped structure. For example, the water dispersible material 102 may be in the form of a sheet (not shown) which may be formed into a continuous rod by rolling, crimping, corrugating or folding. Preferably, the water dispersible material 102 is paper, preferably, paper which has been corrugated to form a creped structure.

[0037] The base weight of the water dispersible material 102 may be at least 20 g / m2, such as at least 25 g / m2, such as at least 30 g / m2. The base weight of the water dispersible material 102 may be up to 60 g / m2, such as up to 55 g / m2, such as up to 50 g / m2. The base weight of the water dispersible material 102 may be from 20 to 60 g / m2, such as from 25 to 55 g / m2, or from 30 to 50 g / m2.

[0038] In one example, the porosity of the water dispersible material 102 may be at least 3500 CU, as measured in accordance with ISO 2965. In one example, the porosity of the water dispersible material 102 may be less than the porosity of the water dispersible wrapper 104. The porosity of the water dispersible material 102 may be up to 10000 CU, more preferably up to 6000CU. Generally providing a water dispersible wrapper 104 with a higher porosity means that it has a tendency to absorb water easier, thereby leading to a higher dispersibility relative to the water dispersible material 102.

[0039] In one embodiment, when the water dispersible material 102 comes into contact with water, the water-soluble binder dissolves and the fibres are able to disperse, which brings about disintegration of the water dispersible material 102.

[0040] The water dispersible wrapper 104 may comprise any suitable fibres. For example, the water dispersible wrapper 104 may comprise fibres selected from wood pulp fibres such as soft-wood kraft pulp, hard-wood kraft pulp or dissolving pulp, and non-wood plant fibres such as kenaf pulp, flax pulp or linter pulp. In one example, the water dispersible material 102 is formed from cellulose fibres. For example, the water dispersible wrapper 104 may comprise cellulose fibres such as paper and / or non-woven fibres. In some examples, the water dispersible wrapper 104 only comprises pulp fibres. That is that it does not contain chemical cellulose fibres and / or plastic fibres.

[0041] As shown in Figure 1 , the water dispersible wrapper 104 may be a sheet-like material which is wrapped around the rod-shaped water dispersible material 102.

[0042] The base weight of the water dispersible wrapper 104 may be at least 15 g / m2, such as at least 20 g / m2, such as at least 25 g / m2. The base weight of the water dispersible wrapper 104 may be up to 55 g / m2, such as up to 50 g / m2, such as up to 45 g / m2. The base weight of the water dispersible wrapper 104 may be from 15 to 55 g / m2, such as from 20 to 50 g / m2, or from 25 to 45 g / m2.

[0043] In one example, the base weight of the water dispersible material 102 may be from 38 to 42 g / m2and the base weight of the water dispersible wrapper 104 may be from 27 to 31 g / m2.

[0044] The total dry weight of the water dispersible material 102 and the water dispersible wrapper 104 may be less than 0.40g. For example, the total dry weight of the water dispersible material and the water dispersible wrapper may be less than 0.35g, such as less than 0.30g, such as less than 0.25g.

[0045] The water dispersibility (£> [%]) of the water dispersible material 102 may be less than the water dispersibility of the water dispersible wrapper 104. For example, the water dispersibility of the water dispersible material 102 may be from 30 to 60%, such as from 40 to 50%; and the water dispersibility of the water dispersible wrapper 104 may be from 50 to 95%, such as from 60 to 85%, or even 70 to 85%.

[0046] In one example, the filter may have a water dispersibility of at least 50%. The filter may have a water dispersibility of at least 55%, such as at least 60%, such as at least 65%, such as at least 70%, such as at least 75%, such as at least 80%, such as at least 85%, or even at least 90%.

[0047] The water dispersibility of the filter 100 was measured by the following method:

[0048] 1 . The initial weight of two filters 100 is measured. 2. The two filters 100 are added to a sample tube containing distilled water. The sample tube has a capacity of approximately 50mL containing approximately 40mL of distilled water. Each of the two filters 100 has a length of 30mm. Note that if a sample is smaller than 30mm, multiple samples may be used to achieve an equivalent size, such that the total length of the filters equals 60mm. For example, if one sample is 10mm, six samples may be used to achieve a length equivalent to two filters of 30mm length.

[0049] 3. The sample tube containing the filters 100 is shaken (130rpm) for 20 minutes.

[0050] 4. The contents of the sample tube are passed through a sieve with a pore size of 9.5mm.

[0051] 5. The recovered filter fragment is oven dried at a temperature of 105°C and the weight of the dry filter fragment is measured.

[0052] The water dispersibility (£> [%] ) was defined as water solubility according to the following equation:

[0053] ( Dry Weight After Experiment [^]) Initial Sample Weight Mo[^] J

[0054] The water dispersibility of the water dispersible wrapper 104 was measured by the following method:

[0055] 1 . The initial weight of the water dispersible wrapper 104 is measured.

[0056] 2. The water dispersible wrapper 104 is added to a sample tube containing distilled water. The sample tube has a capacity of approximately 50mL containing approximately 40mL of distilled water. The water dispersible wrapper 104 is rectangular in shape, corresponding to a typical A6 sheet format (10.5cm x 14.8cm). Note that if a sample that is smaller than A6 format, the measurement may be performed on multiple samples to achieve an equivalent size. For example, if one sample is smaller than the A6 format, multiple samples may be used to achieve an area equivalent to the A6 format.

[0057] 3. The sample tube containing the water dispersible wrapper 104 is shaken (130rpm) for 2 hours.

[0058] 4. The contents of the sample tube are passed through a sieve with a pore size of 9.5mm. 5. The recovered water dispersible wrapper fragment is oven dried at a temperature of 105°C and the weight of the dry wrapper fragment is measured.

[0059] The water dispersibility (£> [%] ) was defined as water solubility according to the following equation:

[0060] ( Dry Weight After Experiment Initial Sample Weight Mo[^] J

[0061] The water dispersibility of the water dispersible material 102 is measured in the same way, by replacing the water dispersible wrapper with the water dispersible material 102.

[0062] The filter may have a hardness of less than 90%. In one example, the filter may have a hardness of less than 85%. The filter may have a hardness of at least 80%. The hardness being at least 80% provides a filter which has improved comfort for the user.

[0063] The term "hardness" as used herein refers to resistance to compression. The hardness is measured by applying a load of 2kg for 20 seconds to ten filters wound with the water dispersible wrappers and measuring the average diameter of the depression in the filter wound with the wrapper. The load is applied by two cylindrical rods and each of the filters has a contact point with each rod. Figure 2 shows a filter 100 in an undeformed state 300, which represents a diameter of the filter before it is subject to force F. Figure 2 also shows the filter 100 in a deformed state 400 after the load F has been applied. The hardness is calculated from the diameter Ds before the load F is applied and the diameter Dd when the load F is applied, by the following equation.

[0064] Hardness (%) = Dd / Ds 100 (%)

[0065] This test can be performed using a DD60A-type Densimeter manufactured by Borgwaldt Corporation. This test is called DD60A test, which is the standard test method for this device. This test is conducted at an ambient temperature of 22 + / - 2 degrees Celsius. Note that if the filter is not long enough to contact each cylindrical rod, the measurement may be performed so that the one filter has one contact point with one cylindrical rod. The filter may have a draw resistance of at least 60 mmWG, such as at least 65, such as at least 70 mmWG, such as at least 75 mmWG, such as at least 80 mmWG, such as at least 85 mmWG. The filter may have a draw resistance of up to 100 mmWG, such as up to 95 mmWG, such as up to 90 mmWG.

[0066] The term "draw resistance" or “resistance of draw” as used herein is well-known in the art and is measured in millimetres water gauge (mmWG) according to ISO 6565.

[0067] In one embodiment, when the filter 100 comes into contact with water, the water dispersible material 102 and the water dispersible wrapper 104 are operable to disintegrate and therefore disperse in the water, such that the dry weight of the filter post-dispersion is less than the dry weight of the filter pre-dispersion.

[0068] The aerosol generation consumable 200 may comprise an aerosol precursor material 120 wrapped with wrapping paper 116; a filter 100; and tipping paper 114 connecting the aerosol generation precursor material 120 and the filter 100.

[0069] As shown in Figure 3, an aerosol generation consumable 200 comprises a filter 100 as previously described and an aerosol substrate portion 106.

[0070] The aerosol substrate portion 106 may be configured to generate aerosol / vapour when heated or combusted. The aerosol substrate portion 106 has an inlet end (or distal end) 108 through which air may be drawn into the aerosol substrate portion 106. The aerosol substrate portion 106 also has an outlet end (or proximal end) 110 through which generated aerosol may exit the aerosol substrate portion 106.

[0071] The filter 100 may be arranged downstream of the outlet end 110 of the aerosol substrate portion 106. In one example, the filter 100 abuts the outlet end 110 of the aerosol substrate portion 106. In another example, not shown in the drawings, an intermediate cooling segment such a tubular member, such as a paper tube or the like, may be arranged between the filter 100 and the aerosol substrate portion 106 contribute to cool the aerosol without increasing the resistance to draw.

[0072] In use, the filter 100 acts as a mouthpiece through which a user draws on the aerosol generating device 200 to inhale generated aerosol and is configured to filter certain components in the aerosol before inhalation thereof by the user, as known in the art. The filter 100 has an inlet end 118 through which aerosol generated from the aerosol substrate portion in use may be drawn into the filter 100. The filter 100 also has an outlet end 112 through which generated aerosol may exit the filter 100 and through which a user inhales the generated aerosol. The filter 100 and aerosol substrate portion may extend coaxially in a substantially longitudinal direction from the outlet end 112 of the filter 100 to the inlet end 108 of the aerosol substrate portion 106. That is to say that the filter 100 and aerosol substrate portion define a longitudinal axis X of the aerosol generation consumable 200 between the outlet end 112 of filter 100 and the inlet end 108 of the aerosol substrate portion 106 and extend coaxially along the longitudinal axis.

[0073] The aerosol generation consumable 200 may may also comprise a tipping paper 114 which connecting the filter 100 and the aerosol consumable portion 106 in longitudinal alignment along longitudinal axis X of the aerosol generation consumable 200. The tipping paper 114 surrounds the water dispersible wrapper 104 and extends along the aerosol generation consumable 200 to surround a portion of the aerosol substrate portion 106.

[0074] In one example, a wrapping layer 116 may be present around the aerosol precursor material 120. The wrapping layer 116 may extend at least from the inlet end 108 to the outlet end 110 of the aerosol substrate portion 106. The wrapping layer 116 is for example formed of cigarette paper, as well known in the art. Where the aerosol consumable article 200 comprises a cooling segment as previously mentioned, the aerosol substrate portion 106 may be individually wrapped with a first wrapping layer and then wrapped together at its outlet end 110 with the cooling segment in longitudinal alignment by the wrapping layer 116. The tipping paper 114 then attaches filter 100 to an outlet end of the cooling segment.

[0075] Although preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in the appended claims and as described above.

[0076] Examples Different paper samples were used as water dispersible material and water dispersible wrappers to form filters according to the present invention. The paper information is set out in Table 1 below. Table 1 - Paper samples

[0077] The filters formed from the different paper samples in Table 1 are set out in Table 2 below.

[0078] Table 2 - Filters

[0079] Even though “Paper 1” and “Paper 2” are listed in the table under the “Water dispersible material” and “Water dispersible wrapper” headings, both paper 1 and paper 2 are nonwater dispersible papers (as described in Table 1) and are therefore not according to the invention.

[0080] The dispersibility, resistance to draw, and hardness of the filters were measured as discussed above and the results are set out in Table 3 below. Table 3 - Results

Claims

CLAIMS1. A filter for an aerosol generation consumable, the filter comprising: a segment comprising a water dispersible material; and a water dispersible wrapper at least partly surrounding the segment, wherein a base weight of the water dispersible material is equal to or higher than a base weight of the water dispersible wrapper.

2. A filter according to claim 1, wherein a base weight of the water dispersible material is higher than a base weight of the water dispersible wrapper.

3. A filter according to claim 1 or 2, wherein the water dispersible material comprises cellulose fibres.

4. A filter according to any one of claims 1 , 2 or 3, wherein the water dispersible material is paper.

5. A filter according to any one of the preceding claims, wherein the water dispersible material comprises a binding agent.

6. A filter according to any one of the preceding claims, wherein the water dispersible wrapper is a paper wrapper.

7. A filter according to any one of the preceding claims, wherein the total dry weight of the water dispersible material and the water dispersible wrapper is less than 0.25g.

8. A filter according to any one of the preceding claims, wherein the base weight of the water dispersible material is from 30 to 50 g / m2.

9. A filter according to any one of the preceding claims, wherein the base weight of the water dispersible wrapper is from 25 to 45 g / m2.

10. A filter according to any preceding claim, wherein the porosity of the water dispersible material is at least 3500 CU.

11. A filter according to any one of the preceding claims, wherein the porosity of the water dispersible material is less than the porosity of the water dispersible wrapper.

12. A filter according to any one of the preceding claims, wherein the water dispersibility rate of the water dispersible material is less than the water dispersibility rate of the water dispersible wrapper.

13. A filter according to any one of the preceding claims, wherein the filter has a water dispersibility of at least 50%.

14. A filter according to any preceding claim, wherein the filter has a hardness of less than 85%.

15. An aerosol generation consumable comprising: an aerosol generation precursor material wrapped with wrapping paper; a filter according to any one of claims 1 to 14; and tipping paper connecting the aerosol generation precursor material and the filter.

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