WO2025004161A1 - Flavor inhaler filter, method for producing same, and flavor inhaler - Google Patents

Abstract

The present invention provides a flavor inhaler filter that contains cellulose fibers and has a high phenol filtration ability. This flavor inhaler filter comprises: a filtration material including a base material that contains cellulose fibers, and a coating layer that is provided on the base material; and a wrapper that is wrapped around the filtration material. The coating layer contains: a homopolymer or copolymer having an acetic acid ester group or hydroxypropyl group on a side chain; cyclodextrin; or lecithin.

Description

Flavor inhaler filter, manufacturing method thereof, and flavor inhaler

The present invention relates to a filter for a flavor inhaler, a method for manufacturing the same, and a flavor inhaler.

Acetate fiber is generally used as the filter material for flavor inhaler filters. However, filter materials containing cellulose fiber have attracted attention because they are more biodegradable than acetate fiber and can reduce environmental impact. Filter materials containing cellulose fiber have lower filtering performance for phenols and other compounds than filter materials containing acetate fiber, and tend to have a harsh flavor. Therefore, attempts have been made to improve the flavor by imparting the ability to filter phenols and other compounds to filter cellulose fiber.

For example, Patent Document 1 discloses the addition of polyalkylene glycol as a filter additive to reduce phenols. Patent Document 2 discloses the addition of triacetin or the like as an additive to reduce phenols. Meanwhile, Patent Document 3 discloses that fibers containing plant pulp are bound with a water-soluble binder when making a nonwoven fabric filter.

JP 2001-352963 A Special Publication No. 2021-515540 International Publication No. 2022/085072

The present invention aims to provide a filter for a flavor inhaler that contains cellulose fibers and has high phenol filtering performance, and a flavor inhaler equipped with the filter.

The present invention includes the following embodiments:

[1] A filter medium including a substrate containing cellulose fibers and a coating layer provided on the substrate;
A wrapper around the filter medium;
A flavor inhaler filter comprising:
A filter, wherein the coating layer comprises a homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin.

[2] The filter according to [1], wherein the homopolymer or copolymer having an acetate ester group in a side chain is at least one selected from the group consisting of polyvinyl acetate, vinyl acetate acrylic copolymer, and ethylene vinyl acetate copolymer.

[3] The filter according to [1] or [2], wherein the filter further contains granular material, and the wrapper wraps the filter medium and the granular material.

[4] The filter according to [3], wherein the granular material is at least one selected from the group consisting of activated carbon, hydrotalcite, and cellulose granules.

[5] The filter according to any one of [1] to [4], wherein the filter medium further contains a hydrophobic fragrance.

[6] The filter according to [5], wherein the hydrophobic flavoring is menthol.

[7] A filter according to any one of [1] to [6], in which the content of the homopolymer or copolymer having an acetate group or a hydroxypropyl group in a side chain, cyclodextrin, or lecithin is 1 to 20% by mass relative to 100% by mass of the filter medium.

[8] A filter according to any one of [1] to [7], having an airflow resistance of 5 to 130 mmWG/27 mmtip.

[9] A filter according to any one of [1] to [8], in which the concentration of the homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin on the surface of the filter medium is higher than the concentration of the homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin inside the filter medium.

[10] The filter according to any one of [1] to [9], wherein the substrate is a sheet of paper or nonwoven fabric containing cellulose fibers.

[11] A flavor inhaler comprising a tobacco rod containing tobacco components and a filter according to any one of [1] to [10].

[12] The flavor inhaler described in [11], which is a combustion type flavor inhaler.

[13] The flavor inhaler described in [12], in which the airflow resistance of the filter is 50 to 130 mmWG/27 mmtip.

[14] The flavor inhaler described in [11], which is a non-combustion heating type flavor inhaler.

[15] The flavor inhaler described in [14], in which the airflow resistance of the filter is 5 to 50 mmWG/27 mmtip.

[16] Preparing a substrate comprising cellulose fibers;
A step of applying a liquid containing a homopolymer or copolymer having an acetate group or a hydroxypropyl group in a side chain, cyclodextrin, or lecithin, and water on the surface of the substrate and drying the liquid to obtain a filter medium;
wrapping the filter medium in a wrapper;
A method for producing a filter for a flavor inhaler, comprising:

[17] The method according to [16], wherein the step of obtaining the filter medium is a step of spraying the liquid onto the surface of the substrate and drying it.

[18] The method according to [16] or [17], wherein the content of the homopolymer or copolymer having an acetate group or a hydroxypropyl group in a side chain, cyclodextrin, or lecithin is 1 to 60% by mass relative to 100% by mass of the liquid.

The present invention provides a filter for a flavor inhaler that contains cellulose fibers and has high phenol filtering performance, and a flavor inhaler that includes the filter.

FIG. 2 is a schematic diagram showing an example of a flavor inhaler filter according to the present embodiment. FIG. 2 is a schematic diagram showing an example of a combustion type flavor inhaler according to the present embodiment. FIG. 2 is a schematic diagram showing an example of a non-combustion heating type flavor inhaler according to the present embodiment. FIG. 1 is a schematic diagram showing an example of a non-combustion heating type flavor inhalation system according to the present embodiment, in which (a) is a state before a non-combustion heating type flavor inhaler is inserted into a heating device, and (b) is a state in which the non-combustion heating type flavor inhaler is inserted into the heating device and heated. 1 is a graph showing the amount of phenol passing through a filter per TPM versus the amount of each phenol trapping component applied in the examples. 1 is a graph showing the airflow resistance of a filter versus the amount of water applied for each phenol-trapping component in the examples.

[Flavor inhaler filter]
The flavor inhaler filter according to the present embodiment includes a filter medium and a wrapper around which the filter medium is wrapped. The filter medium includes a substrate containing cellulose fibers and a coating layer provided on the substrate. The coating layer includes a homopolymer or copolymer having an acetate group or a hydroxypropyl group on a side chain, cyclodextrin, or lecithin.

In the flavor inhaler filter (hereinafter also referred to as "filter") according to this embodiment, the filter medium is made of a base material containing cellulose fibers, and a coating layer containing a homopolymer or copolymer having an acetate ester group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin (hereinafter also referred to as "phenol capture component") is provided on the surface of the base material. Therefore, when vaporized phenol passes through the filter, it chemically interacts with the phenol capture component present on the surface of the filter medium. As a result, phenol is captured on the surface of the filter medium, and phenol filtration performance is improved despite the use of cellulose fibers.

(Substrate)
The substrate according to the present embodiment is not particularly limited as long as it contains cellulose fibers, but may be a sheet-like substrate. The substrate is preferably a sheet-like paper or nonwoven fabric containing cellulose fibers from the viewpoint of high biodegradability and reducing environmental load. The type of paper is not particularly limited, and gather paper, pleated paper, crimp paper, crepe paper, shredded paper, etc. may be used. The method of manufacturing the paper or nonwoven fabric may be either wet or dry, and may be selected as desired.

When the substrate is in sheet form, the thickness of the substrate is not particularly limited, but is usually 20 μm or more, preferably 30 μm or more, and is usually 1.4 mm or less, preferably 1.2 mm or less. The width of the substrate in sheet form is not particularly limited, but is usually 50 mm or more, preferably 100 mm or more, more preferably 170 mm or more, and is 300 mm or less, preferably 250 mm or less, more preferably 230 mm or less.

When the substrate is a sheet-like paper containing cellulose fibers, the basis weight of the paper is not particularly limited, but is usually 20 g/m ² or more, preferably 25 g/m ² or more, and usually 120 g/m ² or less, preferably 80 g/m ² or less, more preferably 45 g/m ² or less. By having the basis weight of 25 g/m ² or more, the tensile strength can be ensured, which is preferable for the production of filters. In addition, by having the basis weight of 80 g/m ² or less, the flexibility of the sheet-like material can be ensured, making it easy to achieve an appropriate pressure drop.

The substrate may have multiple fold lines (also called crimps or crepes) in the axial direction of the filter, allowing it to be folded accordion-like along the fold lines. By providing such fold lines, the filter medium can be folded and gathered when placed inside the wrapper, increasing the surface area of the filter medium. The spacing between the fold lines is not particularly limited, but can be, for example, 0.5 to 4.0 mm.

(Covering layer)
The coating layer according to the present embodiment is provided on the surface of the substrate and contains a homopolymer or copolymer having an acetate group or a hydroxypropyl group in the side chain, cyclodextrin, or lecithin. The coating layer only needs to cover at least a part of the substrate surface, and may cover the entire substrate surface. The coating layer may be made of a homopolymer or copolymer having an acetate group or a hydroxypropyl group in the side chain, cyclodextrin, or lecithin.

As homopolymers or copolymers having acetate ester groups in the side chains, polyvinyl acetate, vinyl acetate acrylic copolymers, and ethylene vinyl acetate copolymers are preferred from the viewpoint of exhibiting higher phenol filtration performance. As homopolymers or copolymers having hydroxypropyl groups in the side chains, hydroxypropyl cellulose and hydroxypropyl methyl cellulose are preferred. As cyclodextrins, α-cyclodextrin, γ-cyclodextrin, and hydroxypropyl cyclodextrin (HP-cyclodextrin) are preferred. These may be used alone or in combination of two or more.

The method for forming the coating layer is not particularly limited, but for example, as described below, the coating layer can be formed by spraying a liquid containing a homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin, and water as a solvent (if necessary, the solvent may further contain glycerin or propylene glycol) onto the surface of the substrate and then drying it.

The phenol trapping component may also be contained in the base material. However, it is preferable that the concentration of the phenol trapping component on the surface of the filter medium is higher than the concentration of the phenol trapping component inside the filter medium, as this improves the phenol trapping performance. Whether the concentration of the phenol trapping component on the surface of the filter medium is higher than the concentration of the phenol trapping component inside the filter medium can be confirmed, for example, by the following method. A cross section of the target filter medium is imaged using microscopic laser Raman spectroscopy. This makes it possible to measure the concentration of the phenol trapping component on the surface and inside the filter medium.

Patent Document 3 also discloses that when forming a nonwoven fabric, fibers containing plant pulp are bound with a water-soluble binder such as polyvinyl acetate. However, in Patent Document 3, polyvinyl acetate is used as a binder to bind the fibers that make up the nonwoven fabric, so the polyvinyl acetate is only present inside the nonwoven fabric, and no coating layer of polyvinyl acetate is formed on the surface of the nonwoven fabric.

(Filter media)
The filter medium according to the present embodiment includes the substrate and the coating layer. The content of the phenol trapping component contained in the filter medium is preferably 1-20% by mass, more preferably 2-11% by mass, and even more preferably 2-7% by mass, of the homopolymer or copolymer having an acetate group or a hydroxypropyl group in the side chain, cyclodextrin, or lecithin, relative to 100% by mass of the filter medium. When the content is 1% by mass or more, the phenol trapping performance is further improved. In addition, when the content is 20% by mass or less, the adhesion of the phenol trapping component to the machine during the filter winding is suppressed, which is preferable in terms of manufacturing suitability.

In addition to the base material and the coating layer, the filter medium may further contain a hydrophobic fragrance. In this embodiment, the filter medium has a coating layer containing a homopolymer or copolymer having an acetate ester group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin, and therefore has a high hydrophobic fragrance carrying capacity. In this embodiment, examples of hydrophobic fragrances include menthol, cocoa (powder, extract, etc.), esters (isoamyl acetate, linalyl acetate, isoamyl propionate, linalyl butyrate, etc.), natural essential oils (vegetable essential oils such as vanilla extract, spearmint, peppermint, cassia, jasmine, etc.; animal essential oils such as musk, ambergris, civet, castoreum, etc.), single fragrances (anethole, limonene, linalool, eugenol, vanillin, etc.), etc., and menthol is preferred. These hydrophobic fragrances may be used alone or in combination of two or more. When the filter medium contains a hydrophobic fragrance, the content of the hydrophobic fragrance contained in the filter medium is preferably 10 to 50% by mass relative to 100% by mass of the filter medium.

(Filter configuration, etc.)
The filter according to this embodiment is configured by wrapping the filter material with a wrapper. An example of the filter according to this embodiment is shown in FIG. 1. The filter 1 shown in FIG. 1 includes a filter material 2 including the substrate and the coating layer, and a cylindrical wrapper 3 that wraps the filter material 2. Examples of the material of the wrapper 3 include paper. The filter material 2 has a plurality of fold lines in the axial direction of the filter 1, i.e., in the horizontal direction of FIG. 1, and is gathered while being folded in an accordion-like shape along the fold lines and filled in the wrapper 3. The grooves formed by the gathers extend in the axial direction of the filter 1. By filling the filter material 2 in this way in the filter 1, the surface area of the filter material 2 can be increased while maintaining the permeability of aerosols and flavor components in the axial direction of the filter 1. This allows the filter material 2 to efficiently and selectively capture phenol.

The filter according to this embodiment may further include granular materials. In this case, the wrapper may further wrap the granular materials in addition to the filter medium. In the cylindrical wrapper, the granular materials may be located, for example, on the surface of the filter medium or in the gaps between the filter medium. In this embodiment, the filter medium has a coating layer containing a homopolymer or copolymer having an acetate ester group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin, so that the surface of the filter medium is highly adhesive. As a result, when granular materials are placed in the filter, the granular materials have a high carrying capacity and can be prevented from falling off. Examples of granular materials include activated carbon, hydrotalcite, and cellulose granules. These may be used alone or in combination of two or more types. Activated carbon has the effect of smoothing the flavor. Hydrotalcite can selectively adsorb specific vapor phase components. Cellulose granules can increase the amount of permeation of particle phase components and semi-volatile components. The average particle size of the granular materials is not particularly limited, but may be, for example, 200 to 1500 μm. If the filter contains granular matter, the amount of granular matter contained is preferably 1 part by weight to 50 parts by weight, and more preferably 1 part by weight to 20 parts by weight, per 100 parts by weight of the filter medium.

The airflow resistance of the filter according to this embodiment is preferably 5 to 130 mmWG/27 mmtip when the axial length of the filter is 27 mm. For example, when the filter is a filter for a combustion type flavor inhaler, the airflow resistance is preferably 50 to 130 mmWG/27 mmtip. On the other hand, when the filter is a filter for a non-combustion heating type flavor inhaler, the airflow resistance is preferably 5 to 50 mmWG/27 mmtip. As described below, the airflow resistance can be adjusted by adjusting the amount of water applied when applying a liquid containing a vinyl acetate homopolymer or copolymer or hydroxypropyl cellulose and water to the surface of the substrate and drying to form a coating layer. It can also be adjusted by the packing density of the filter material filled in the filter. The airflow resistance can be measured with an airflow resistance meter (product name: SODIMAX, manufactured by SODIM).

The shape of the filter according to this embodiment is not particularly limited, but can be, for example, columnar. When the filter is columnar, the circumferential length of the filter can be changed as appropriate according to the size of the product to be used, but is usually 14.0 mm or more, preferably 15.0 mm or more, more preferably 16.0 mm or more, and is usually 27.0 mm or less, preferably 26.0 mm or less, more preferably 25.0 mm or less. The axial length of the filter can be changed as appropriate according to the size of the product, but may be 5 mm or more, 10 mm or more, 15 mm or more, 17.5 mm or more, or 20.0 mm or more, and may be 40 mm or less, 35 mm or less, 32.5 mm or less, or 30.0 mm or less. The cross-sectional shape of the filter is not particularly limited, but can be, for example, circular, elliptical, polygonal, etc.

[Method of manufacturing a filter for a flavor inhaler]
The method for producing the flavor inhaler filter according to the present embodiment includes the following steps: preparing a substrate containing cellulose fibers; applying a liquid containing a homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin, and water on the surface of the substrate and drying the liquid to obtain a filter medium; and wrapping the filter medium with a wrapper. According to the above method, the filter according to the present embodiment can be produced efficiently and simply.

The method according to this embodiment can be carried out, for example, by the following method. While unwinding a raw material sheet, which is a base material containing cellulose fibers, from a raw paper roll, the raw material sheet is wrinkled vertically, gathered, wrapped with a wrapper by a filter winding machine, and formed into a rod shape, and then cut to a specified size. Here, between the step of unwinding the raw material sheet from the raw paper roll and the step of winding it with a wrapper, a liquid containing a homopolymer or copolymer having an acetate ester group or a hydroxypropyl group on a side chain, cyclodextrin, or lecithin, and water is applied to the surface of the raw material sheet and dried. For example, after unwinding the raw material sheet from the raw paper roll and before being fed to the filter winding machine, the liquid can be applied to the raw material sheet and dried. Also, the liquid may be applied to the raw material sheet on the filter winding machine before winding the wrapper.

In the process of applying liquid to the surface of the substrate and drying it, the distance between the fibers of the substrate becomes shorter, causing it to shrink (i.e., the apparent density of the substrate decreases). This is thought to be due to the influence of the water contained in the liquid as a solvent. Therefore, when comparing substrates of the same amount, those that are dried after applying liquid (water) have a smaller volume than those that are not applied, and the air resistance is reduced when the filter is formed. Therefore, by adjusting the amount of water applied when applying the liquid, the air resistance of the resulting filter can be adjusted to the desired value. It is believed that the phenol-trapping components contained in the liquid do not contribute to the reduction in the volume of the substrate.

The liquid may contain, in addition to water, for example, glycerin or propylene glycol as a solvent. When a homopolymer or copolymer having an acetate ester group on the side chain is used as the phenol-trapping component, an emulsion is formed when this component is mixed with water as the solvent. On the other hand, when a homopolymer or copolymer having a hydroxypropyl group on the side chain, cyclodextrin, or lecithin is used as the phenol-trapping component, glycerin or propylene glycol can be used as the solvent in addition to water.

The step of obtaining the filter medium is preferably a step of spraying the liquid onto the surface of a substrate and drying the liquid, from the viewpoint of being able to apply the liquid uniformly onto the substrate surface. The content ratio of the homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin relative to 100% by mass of the liquid is preferably 1 to 60% by mass, more preferably 2 to 40% by mass, and even more preferably 4 to 25% by mass. By having the ratio be 1 to 60% by mass, the phenol capture component can be applied uniformly onto the substrate. The liquid can be dried by heating, natural drying, or the like.

[Flavor inhaler]
The flavor inhaler according to the present embodiment includes a tobacco rod containing tobacco components and a filter according to the present embodiment. The flavor inhaler according to the present embodiment includes the filter according to the present embodiment, so that phenol is sufficiently filtered during use, and the amount of phenol is reduced. Examples of the flavor inhaler include a combustion type flavor inhaler (cigarette, cigarette) that burns a tobacco rod to obtain flavor, and a non-combustion heating type flavor inhaler that heats a tobacco rod instead of burning it to obtain flavor.

(Combustion-type flavor inhaler)
An example of a combustion type flavor inhaler according to the present embodiment is shown in FIG. 2. As shown in FIG. 2, the combustion type flavor inhaler 11 includes a tobacco rod 12 and a filter 13 according to the present embodiment provided adjacent to the tobacco rod 12. The airflow resistance of the filter 13 is preferably 50 to 130 mmWG/27 mmtip. The tobacco rod 12 includes a tobacco filler 14 filled with tobacco leaves or the like, and a wrapper 15 wrapped around the tobacco filler 14. The tobacco rod 12 and the filter 13 are connected by a tipping paper member 16 wrapped around the tobacco rod 12 and the filter 13. The tipping paper member 16 may have an air hole in a part of its outer periphery. The number of the air holes may be one or more, and may be, for example, 10 to 40. When the number of the air holes is more than one, the air holes may be arranged in a line in a ring shape on the outer periphery of the tipping paper member 16. The multiple air holes may be arranged at approximately regular intervals. By providing the vent hole, air is taken into the filter 13 through the vent hole during inhalation. By diluting the mainstream smoke with outside air from the vent hole, a product with a desired tar value can be designed. A typical example of such a combustion type flavor inhaler is a cigarette.

The user can enjoy the flavor of tobacco by lighting the tip of the tobacco rod 12 and inhaling by placing the mouth end of the filter 13 in the mouth. In particular, because the combustion-type flavor inhaler 11 is equipped with the filter 13 according to this embodiment, the amount of phenol in the flavor supplied is reduced, making the harshness of the flavor milder.

(Non-combustion heating type flavor inhaler)
An example of a non-combustion heating type flavor inhaler according to this embodiment is shown in Fig. 3. The non-combustion heating type flavor inhaler 20 shown in Fig. 3 includes a tobacco rod 21 and a mouthpiece segment 22. The mouthpiece segment 22 includes a cooling segment 23, a first filter 24 which is a filter according to this embodiment, and a second filter 25. The first filter 24 preferably has an airflow resistance of 5 to 50 mmWG/27 mmtip. During inhalation, the tobacco rod 21 is heated, and each component contained in the tobacco filler is vaporized, and these are transferred to the mouthpiece segment 22 by inhalation. Inhalation is then performed from the end of the filter 25.

The tobacco rod 21 has a tobacco filler containing tobacco and an aerosol-generating base material, and a cylindrical wrapper that covers the tobacco filler. Examples of aerosol-generating base materials include glycerin and propylene glycol. The tobacco filler may further contain volatile flavoring components, water, etc. There are no particular limitations on the size of the tobacco used as the filler or the method of preparation thereof. For example, dried tobacco leaves that have been chopped may be used. Dried tobacco leaves that have been crushed and homogenized may be processed into sheets that are then chopped. Furthermore, the above-mentioned sheet-processed material may be gathered without being chopped and used as the filler. Whether dried tobacco leaves are chopped and used, or crushed and homogenized sheets, various types of tobacco may be used as the tobacco filler. Flue, Burley, Orient, native, and other Nicotiana tabacum and Nicotiana rustica varieties may be appropriately blended to achieve the desired flavor. Details of the tobacco varieties are disclosed in the "Encyclopedia of Tobacco, Tobacco Research Center, March 31, 2009."

The cooling segment 23 can be composed of a cylindrical member 26. The cylindrical member 26 can be, for example, a paper tube made by processing cardboard into a cylindrical shape. The cylindrical member 26 and the mouthpiece lining paper 31 described later are provided with perforations 27 penetrating both. Due to the presence of the perforations 27, outside air is introduced into the cooling segment 23 during inhalation. As a result, the vaporized components of the aerosol generated by heating the tobacco rod 21 come into contact with the outside air, and as their temperature drops, they are liquefied, forming an aerosol. The diameter (distance across) of the perforations 27 is not particularly limited, but can be, for example, 0.5 to 1.5 mm. The number of perforations 27 is not particularly limited, and may be one or more than two. For example, a plurality of perforations 27 may be provided on the circumference of the cooling segment 23.

The first filter 24 is a filter according to this embodiment that contains a phenol trapping component, and the second filter 25 is a filter similar to the filter according to this embodiment except that it does not contain a phenol trapping component. The first filter 24 may be a filter similar to the filter according to this embodiment except that it does not contain a phenol trapping component, and the second filter 25 may be a filter according to this embodiment that contains a phenol trapping component. Furthermore, both the first filter 24 and the second filter 25 may be filters according to this embodiment that contain a phenol trapping component. Note that only one filter according to this embodiment may be provided without providing a filter that does not contain a phenol trapping component.

The first filter 24 and the second filter 25 are connected by an outer plug wrapper 28. The outer plug wrapper 28 can be, for example, a cylindrical piece of paper. The tobacco rod 21, the cooling segment 23, and the connected first filter 24 and second filter 25 are connected by a mouthpiece lining paper 29. These can be connected by, for example, applying a glue such as a vinyl acetate glue to the inner surface of the mouthpiece lining paper 29, inserting the three segments, and rolling them up. Since the non-combustion heating type flavor inhaler 20 is equipped with the first filter 24 according to this embodiment, the amount of phenol in the flavor supplied is reduced, and the harshness of the flavor is mitigated.

[Non-combustion heating type flavor inhalation system]
The non-combustion heating type flavor inhalation system according to the present embodiment may include the non-combustion heating type flavor inhaler according to the present embodiment described above and a heating device for heating the non-combustion heating type flavor inhaler. The non-combustion heating type flavor inhalation system according to the present embodiment may have other configurations in addition to the non-combustion heating type flavor inhaler according to the present embodiment and the heating device.

An example of a non-combustion heating type flavor inhalation system according to this embodiment is shown in FIG. 4. The non-combustion heating type flavor inhalation system shown in FIG. 4 includes a non-combustion heating type flavor inhaler 40 according to this embodiment, and a heating device 41 that heats the tobacco rod of the non-combustion heating type flavor inhaler 40 from the outside. FIG. 4(a) shows the state before the non-combustion heating type flavor inhaler 40 is inserted into the heating device 41, and FIG. 4(b) shows the state after the non-combustion heating type flavor inhaler 40 is inserted into the heating device 41 and heated. The heating device 41 shown in FIG. 4 includes a body 42, a heater 43, a metal tube 44, a battery unit 45, and a control unit 46. The body 42 has a cylindrical recess 47, and the heater 43 and the metal tube 44 are arranged on the inner side of the recess 47 at a position corresponding to the tobacco rod of the non-combustion heating type flavor inhaler 40 inserted into the recess 47. The heater 43 can be a heater that uses electrical resistance, and is heated by power supplied from a battery unit 45 in response to instructions from a control unit 46 that controls temperature. The heat generated by the heater 43 is transferred to the tobacco rod of the non-combustion heating type flavor inhaler 40 through a metal tube 44 with high thermal conductivity.

Since FIG. 4(b) is a schematic illustration, there is a gap between the outer circumference of the non-combustion heating type flavor inhaler 40 and the inner circumference of the metal tube 44, but in reality, it is preferable that there is no gap between the outer circumference of the non-combustion heating type flavor inhaler 40 and the inner circumference of the metal tube 44 in order to efficiently transfer heat. In addition, the heating device 41 heats the tobacco rod of the non-combustion heating type flavor inhaler 40 from the outside, but it may also heat from the inside. If it heats from the inside, it is preferable to use a rigid plate-shaped, blade-shaped, or columnar heater without using the metal tube 44. Examples of such heaters include ceramic heaters in which molybdenum, tungsten, or the like is applied to a ceramic substrate.

The heating temperature by the heating device is not particularly limited, but is preferably 400°C or less, more preferably 150°C to 400°C or less, and even more preferably 200°C to 350°C or less. The heating temperature refers to the temperature of the heater of the heating device.

　Below, this embodiment will be described in detail with reference to examples, but this embodiment is not limited to these examples.

[Example 1]
An emulsion was prepared by mixing 20% by weight of vinyl acetate acrylic copolymer and 80% by weight of water. The emulsion was sprayed onto both surfaces of a corrugated paper (basis weight 40 g/m ² ) (amount of vinyl acetate acrylic copolymer applied: 26 mg), and dried at room temperature for 30 minutes to 1 hour. As a result, a filter medium was obtained in which a coating layer of vinyl acetate acrylic copolymer was formed on the substrate surface. The content ratio of vinyl acetate acrylic copolymer to 100% by weight of the filter medium was 10.9% by weight. The filter medium was folded to form a plurality of air flow paths each extending from one end to the other end, and wrapped with a paper wrapper to form a filter. The filter was joined to a tobacco rod of a commercially available cigarette (product name: Winston Filter, manufactured by Japan Tobacco Inc.) to prepare a cigarette. The tip of the tobacco rod of the cigarette was burned and used to measure the amount of phenol in the cigarette smoke passing through the filter. The results are shown in Table 2.

The amount of phenol passing through the filter was measured by the following method. Using an automatic smoking machine (Cerulean SM410), cigarette samples were automatically smoked under the following conditions: smoke volume 17.5 mL/sec, puff time 2 sec/puff, puff frequency 1 puff/min, butt length 35 mm, and total particulate matter (TPM) in the cigarette smoke was collected with a Cambridge filter (Borgwaldt 44 mmφ). The amount of TPM was measured by the mass difference of the Cambridge filter before and after smoking. The Cambridge filter was then immersed in 10 mL of the phenol extraction solvent shown in Table 1 in a screw cap bottle and shaken to obtain an analytical sample. 1 μL of the obtained analytical sample was collected with a microsyringe and analyzed by gas chromatography-mass spectrometry (GC-MSD: Gas Chromatography-Mass Selective Detector). The GC used was an Agilent G7890A manufactured by Agilent Technologies Inc., and the MSD used was an Agilent_5795C manufactured by Agilent Technologies Inc.

The amount of phenol passing through the filter is the amount of phenol equivalent to TPM (total particulate matter) that passes through the filter, and is shown as a relative value when the amount of phenol passing through the filter in Comparative Example 1 (an example in which a coating layer is not formed) described below is set to 1.

[Examples 2 to 13, Comparative Examples 1 and 2]
A filter was prepared and evaluated in the same manner as in Example 1, except that the components shown in Table 2 were used as the phenol trapping components, and the concentration of the phenol trapping components in the solution and the amount of the phenol trapping components applied were changed as shown in Table 2. The results are shown in Table 2. In Example 7, a commercially available non-combustion heating type flavor inhaler (product name: Mevius Rich Ploom X Ploom S, manufactured by Japan Tobacco Inc.) and a heating device (product name: PloomX, manufactured by Japan Tobacco Inc.) were used instead of commercially available cigarettes. A filter containing cellulose acetate fiber and a center hole segment were taken out from the non-combustion heating type flavor inhaler. A paper filter not containing a phenol trapping component was inserted in the position of the center hole segment of the filter prepared in the same manner as in Example 1, to obtain a non-combustion heating type flavor inhaler having the configuration shown in FIG. 3. In addition, in Comparative Example 1, a coating layer was not formed, and evaluation was performed as it was.

As shown in Table 2, in Examples 1 to 13, which used filter media with a coating layer containing a homopolymer or copolymer having an acetate group or a hydroxypropyl group in the side chain, cyclodextrin, or lecithin, the amount of phenol passing through the filter was reduced compared to Comparative Example 1, which used filter media without a coating layer. On the other hand, in Comparative Example 2, which used filter media with a coating layer containing polyvinyl alcohol, the amount of phenol passing through the filter was slightly increased compared to Comparative Example 1.

[Examples 14 to 34]
Filters were prepared and evaluated in the same manner as in Example 1, except that the components shown in Table 3 were used as the phenol-trapping components, and the concentrations of the phenol-trapping components in the solutions, the amounts of the phenol-trapping components added, and the amounts of water added were changed as shown in Table 3. Furthermore, the airflow resistance was measured for the filters of Examples 3 to 8 and Examples 14 to 34. The results are shown in Table 3. Graphs showing the amount of phenol passing through the filter per TPM relative to the amount of each phenol-trapping component added, and the airflow resistance of the filter relative to the amount of water added for each phenol-trapping component are shown in Figures 5 and 6, respectively. Note that in measuring the airflow resistance of the filter of Example 7, the axial length was converted to 27 mm for calculation.

As shown in Table 3, in Examples 3 to 8 and 14 to 34, which used filter media with a coating layer containing a homopolymer or copolymer having acetate groups or hydroxypropyl groups in the side chain, cyclodextrin, or lecithin, the amount of phenol passing through the filter was reduced compared to Comparative Example 1, even when the amount of phenol-trapping component added was changed to change the content of the phenol-trapping component in the filter media. Furthermore, in Examples 3 to 6, 8, and 14 to 34, the airflow resistance of the filter was reduced by increasing the amount of water added. This shows that the airflow resistance of the resulting filter can be adjusted to a desired value by adjusting the amount of water added when liquid is added.

The present embodiment includes the following aspects.
[1] A filter medium including a substrate containing cellulose fibers and a coating layer provided on the substrate;
A wrapper around the filter medium;
A flavor inhaler filter comprising:
A filter, wherein the coating layer comprises a homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin.
[2] The filter according to [1], wherein the homopolymer or copolymer having an acetate group in a side chain is at least one selected from the group consisting of polyvinyl acetate, vinyl acetate acrylic copolymer, and ethylene vinyl acetate copolymer.
[3] The filter according to [1] or [2], wherein the filter further comprises particulate matter, and the wrapper wraps the filter medium and the particulate matter.
[4] The filter according to [3], wherein the granular material is at least one selected from the group consisting of activated carbon, hydrotalcite, and cellulose granules.
[5] The filter according to any one of [1] to [4], wherein the filter medium further contains a hydrophobic fragrance.
[6] The filter according to [5], wherein the hydrophobic flavoring is menthol.
[7] The filter according to any one of [1] to [6], wherein the content of the homopolymer or copolymer having an acetate group or a hydroxypropyl group in a side chain, cyclodextrin, or lecithin is 1 to 20% by mass relative to 100% by mass of the filter medium.
[8] The filter according to any one of [1] to [7], having an airflow resistance of 5 to 130 mmWG/27 mmtip.
[9] The filter according to any one of [1] to [8], wherein the concentration of the homopolymer or copolymer having an acetate group or a hydroxypropyl group on a side chain, cyclodextrin, or lecithin on the surface of the filter medium is higher than the concentration of the homopolymer or copolymer having an acetate group or a hydroxypropyl group on a side chain, cyclodextrin, or lecithin inside the filter medium.
[10] The filter according to any one of [1] to [9], wherein the substrate is a sheet of paper or nonwoven fabric containing cellulose fibers.
[11] A flavor inhaler comprising a tobacco rod containing tobacco components and the filter according to any one of [1] to [10].
[12] The flavor inhaler according to [11], which is a combustion type flavor inhaler.
[13] The flavor inhaler described in [12], wherein the air resistance of the filter is 50 to 130 mmWG/27 mmtip.
[14] The flavor inhaler according to [11], which is a non-combustion heating type flavor inhaler.
[15] The flavor inhaler described in [14], wherein the air resistance of the filter is 5 to 50 mmWG/27 mmtip.
[16] Preparing a substrate comprising cellulose fibers;
A step of applying a liquid containing a homopolymer or copolymer having an acetate group or a hydroxypropyl group in a side chain, cyclodextrin, or lecithin, and water on the surface of the substrate and drying the liquid to obtain a filter medium;
wrapping the filter medium in a wrapper;
A method for producing a filter for a flavor inhaler, comprising:
[17] The method according to [16], wherein the step of obtaining the filter medium is a step of spraying the liquid onto the surface of the substrate and drying it.
[18] The method according to [16] or [17], wherein the content of the homopolymer or copolymer having an acetate group or a hydroxypropyl group at a side chain, cyclodextrin, or lecithin is 1 to 60% by mass relative to 100% by mass of the liquid.

1 Filter 2 Filter media 3 Wrapper

Claims (18)

A filter medium including a substrate including cellulose fibers and a coating layer provided on the substrate;
A wrapper around the filter medium;
A flavor inhaler filter comprising:
A filter, wherein the coating layer comprises a homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin. The filter according to claim 1, wherein the homopolymer or copolymer having an acetate ester group in a side chain is at least one selected from the group consisting of polyvinyl acetate, vinyl acetate acrylic copolymer, and ethylene vinyl acetate copolymer. The filter of claim 1 or 2, wherein the filter further comprises granular material, and the wrapper wraps the filter medium and the granular material. The filter according to claim 3, wherein the granular material is at least one selected from the group consisting of activated carbon, hydrotalcite, and cellulose granules. The filter according to any one of claims 1 to 4, wherein the filter medium further comprises a hydrophobic fragrance. The filter of claim 5, wherein the hydrophobic flavoring is menthol. The filter according to any one of claims 1 to 6, wherein the content of the homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin is 1 to 20% by mass relative to 100% by mass of the filter medium. The filter according to any one of claims 1 to 7, having an airflow resistance of 5 to 130 mmWG/27 mm tip. The filter according to any one of claims 1 to 8, wherein the concentration of the homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin on the surface of the filter medium is higher than the concentration of the homopolymer or copolymer having an acetate group or a hydroxypropyl group on the side chain, cyclodextrin, or lecithin inside the filter medium. The filter according to any one of claims 1 to 9, wherein the substrate is a sheet of paper or nonwoven fabric containing cellulose fibers. A flavor inhaler comprising a tobacco rod containing tobacco components and a filter according to any one of claims 1 to 10. The flavor inhaler according to claim 11, which is a combustion type flavor inhaler. The flavor inhaler according to claim 12, wherein the airflow resistance of the filter is 50 to 130 mmWG/27 mm tip. The flavor inhaler according to claim 11, which is a non-combustion heating type flavor inhaler. The flavor inhaler according to claim 14, wherein the airflow resistance of the filter is 5 to 50 mmWG/27 mm tip. Providing a substrate comprising cellulose fibers;
A step of applying a liquid containing a homopolymer or copolymer having an acetate group or a hydroxypropyl group in a side chain, cyclodextrin, or lecithin, and water on the surface of the substrate and drying the liquid to obtain a filter medium;
wrapping the filter medium in a wrapper;
A method for producing a filter for a flavor inhaler, comprising: The method according to claim 16, wherein the step of obtaining the filter medium is a step of spraying the liquid onto the surface of the substrate and drying it. The method according to claim 16 or 17, wherein the content of the homopolymer or copolymer having an acetate group or a hydroxypropyl group on a side chain, cyclodextrin, or lecithin is 1 to 60% by mass relative to 100% by mass of the liquid.