ES2774441T3 - Filter element for a smoking article - Google Patents

Abstract

A filter element (10; 110; 210; 210 '; 310; 410; 510) for use in a smoking article (80), the filter element (10) being formed from a filter material (20), such as cellulose acetate, wherein the filter element (10) includes a cavity (30; 130) devoid of filter material (20), wherein the cavity (30; 130) forms a channel that extends completely through the element (10; 110) filter, along a longitudinal direction (L) of the filter element (10; 110), wherein the channel (130) is a tube that is formed from a material (50; 150 ) of tube, said tube material being different from the filter material, wherein at least one internal surface of the tube material facing the tube cavity is provided at least partially with an adsorbent (40), wherein the tube is formed as a single central core of the filter element (210; 310).

Description

DESCRIPTION

Filter element for a smoking article

Field of the invention

The present invention relates generally to a filter element for a smoking article and to a smoking article including such a filter element.

Background of the invention

Filter elements for smoking articles are generally known in the art. Such filter elements are basically used to screen filterable materials in the smoke generated while smoking.

The invention is primarily directed to filter elements for conventional smoking articles, such as cigarettes. However, with respect to the present invention, the terms "smoking article" and "smoking" are intended to include both conventional smoking articles, such as cigarettes, where tobacco is burned to generate inhalable smoke, as well as electronic smoking or vaping devices. , such as electronic cigarettes or shishas, where a respective liquid is vaporized or atomized to generate inhalable vapor. Such vapor is also referred to as "smoke" hereinafter.

US 3,438,381 relates to a tobacco smoke filter having a plurality of longitudinal channels formed therein, each of which has a rough wall structure. The channels are coated with a viscous substance, such as honey, to trap harmful ingredients contained in the smoke. Document TW 2011/32303 A discloses a charcoal filter characterized by comprising supplemental carbon on the surfaces of carbon-containing papers, and folding within the papers.

Document DE 34 44 991 A1 relates to a filter cartridge for smokers' articles, such as tobacco pipes, cigarette tips and cigars, consisting of a spirally designed core of porous material and a housing enclosing the latter. The multi-turn spiral body that forms the central core consists of an adsorbent porous organic material, composed of a material containing albumin, to which is added, if necessary, a proportion of active carbon particles, the spiral body on its surface with active carbon particles.

US 2005/133053 A1 and WO 2004/080217 A1 disclose smoking articles involving the use of a copper exchanged molecular sieve catalyst that is capable of removing NO and / or NO2 from the mainstream smoke. . The copper exchanged molecular sieve catalyst comprises a microporous molecular sieve substrate, having pores with an average diameter of about 3 AA to about 15 AA, in which at least some of the pores of the microporous molecular sieve substrate contain Cu ions. +2 Also described in these documents are methods for making cigarette filters and smoking articles using the copper exchanged molecular sieve catalyst, as well as methods for smoking a cigarette comprising the copper exchanged molecular sieve catalyst.

The sensation of smoking can be influenced by filter elements in a number of ways. An object of the present invention is to suggest a new filter element that provides both an effective filtering action and a satisfactory sensation when smoking.

This object is solved by a filter element with the characteristics of the independent claim. Preferred embodiments and further developments are described with respect to the dependent claims.

Summary of the invention

In accordance with one aspect of the present invention, a filter element is provided for use in a smoking article. The filter element is made of a conventional filter material, such as cellulose acetate. The filter element includes a cavity lacking filter material, wherein one surface of the cavity is at least partially provided with at least one adsorbent. According to a first variant, the respective surface is partially or completely provided with an adsorbent.

According to a second alternative variant, the surface of the cavity can be provided with a first adsorbent in a first area of the surface, and with a second adsorbent that is different from the first adsorbent in a second area of the surface, said second differing area at least partially relative to the first area.

The adsorbent can be at least one of a group of adsorbents including activated carbon, zeolites, alumina, silica, silica gel, ion exchange resins, polyester resins, sepiolite, and carbon species, such as impregnated carbon, activated carbon fibers, or highly activated carbon. Suitable adsorbents and / or catalysts known in the art can be used to filter smoke or remove components from the smoke.

The cavity forms a channel that extends completely through the filter element, and at least partially along a longitudinal direction of the filter element. Preferably, the cavity or channel extends along a direction along which smoke is drawn during operation of a smoking article including the filter element, i.e. when the user absorbs or inhales into the article of smoke. With respect to an arrangement of the filter element in a smoking article, according to a first variant, the cavity or channel extends into the filter element from a mouth side. According to a second alternative variant, the channel or cavity can extend into the filter element from a cylinder side.

While smoking, the cavity or channel devoid of filter material allows the passage of at least a certain amount of smoke through the filter element without being filtered, that is, with an original flavor that is not altered when passing through the material of the filter. filter element. In this way, the sensation obtained from smoking can be improved.

On the other hand, due to the provision of the adsorbent on the inner surface of the filter element facing towards the cavity, some filtering or retention effect can still be provided with respect to the portion of smoke passing through the cavity or channel, and not through the filter material surrounding the cavity or channel. Furthermore, providing the adsorbent on the internal surface of the cavity and not embedding it in the filter material results in a lower pressure drop, compared to a solution in which the adsorbent is embedded in the filter material. .

The shape and dimension of the cavity or channel can vary. It goes without saying that the aforementioned effect of the cavity or channel increases proportionally to the size or volume of the cavity in relation to the size or volume of the filter element, ie the filter material surrounding the cavity or channel. It is also possible to provide more than one cavity or channel. In this way, the active surface area, ie the surface which is provided with the adsorbent, can be increased in particular, which increases the retention effect of the adsorbent. One or more channels can e.g. ex. extend in parallel along a longitudinal direction of the filter element, which generally has a circular-cylindrical shape. Furthermore, the channel (s) may have a circular-cylindrical shape, and may extend into / through the filter element partially, as a blind hole, or completely, as a through hole.

According to a first embodiment, which is not part of the invention, the cavity or channel is formed directly in the filter element, that is, the surface of the filter element facing the cavity is formed by filter material. With respect to the present embodiment, the adsorbent is applied directly to the inner surface of the cavity, that is, to the filter material in this area.

According to a second embodiment, which is part of the invention, the cavity or channel is a tube that is formed from a sheet-type tube material, preferably self-supporting. According to the present embodiment, the cavity or channel has a wall separate from the filter material of the filter element. In general, a tube material differs from filter material. However, the tube can also be formed from the same material, such as cellulose acetate. Providing such a tube in advance can serve to simplify the production of the filter element of the invention. The tube is formed as a single central or internal filter element core, the central core of which, in the finished filter element, is surrounded by filter material.

Some suitable tube materials are eg. ex. paper materials or polymeric materials known in the art. The tube material can include a layer or a plurality of layers, e.g. ex. two or three layers of paper.

Specifically, in accordance with the invention, at least the inner surface of the tube material facing the tube cavity is at least partially provided with the adsorbent. The adsorbent can be applied to the respective surface by any suitable application technology.

According to a variant, the tube material can already include the adsorbent. In particular, carbon paper can be used as the tube material or as a layer of a multilayer tube material. In case the tube material includes multiple layers, at least the innermost layer of the multiple layers, ie the layer facing the tube cavity, includes the adsorbent.

According to a third embodiment, a cavity or channel formed directly in the filter element can be partially lined with a liner material corresponding to the tube material. The adsorbent can be applied or integrated into the coating material, as described above with respect to the tube material.

According to a further embodiment, it is possible to color or print the tube material or the lining material, at least on the surface facing the cavity, to achieve visual differentiation and recognition.

A smoking article of the invention includes a filter element described above.

According to a preferred embodiment, the smoking article, in the form of a conventional cigarette, includes a wrapped tobacco cylinder and a filter. The filter consists of or includes at least one of the filter elements of the invention. The wrapped tobacco cylinder and the filter are connected by a tipping paper that surrounds the filter and a part of the wrapped tobacco cylinder.

According to a preferred embodiment, the filter includes at least a first filter element and a second filter element of the type described above, wherein a surface of the first filter element facing the cavity of the first filter element is provided with a first adsorbent, and wherein a surface of the second filter element facing the cavity of the second filter element is provided with a second adsorbent, which is different from the first adsorbent.

The features, functions and advantages of the present invention and the manner in which they are obtained as described above, will become more apparent and more clearly understood in connection with the following description of exemplary embodiments, which are explained with reference to accompanying drawings. .

Brief description of the drawings

In the drawings, the same item numbers indicate the same items in each of the views:

Figure 1A is a schematic cross-sectional illustration of an exemplary filter element;

Figure 1B shows the filter element of Figure 1A in a front view;

Figure 2 is a schematic cross-sectional illustration of an exemplary filter element;

Figure 3A is a schematic cross-sectional illustration of an exemplary filter element according to a first variant of a third embodiment;

Figure 3B is a schematic cross-sectional illustration of an exemplary filter element according to a second variant of the third embodiment;

Figure 4 is a schematic cross-sectional illustration of an exemplary filter element in accordance with the invention;

Figure 5A is a schematic cross-sectional illustration of an exemplary filter element;

Figure 5B shows the filter element of Fig. 5A in front view;

Figure 6A is a schematic cross-sectional illustration of an exemplary smoking article, including the filter element of Fig. 4;

Figure 6B is a schematic cross-sectional illustration of an exemplary smoking article, including the filter element of Fig. 4 as a first filter element and a variant of the filter element of Fig. 4 as a second element. filter; and

Figure 6C is a schematic cross-sectional illustration of an exemplary smoking article including the filter element of Fig. 2.

The figures are not generally drawn to scale, but only indicate in an exemplary manner the elements of the respective filter elements and smoking articles.

Description of the preferred embodiments

Figure 1A is a schematic cross-sectional illustration of an exemplary filter element 10. Figure 1B shows the filter element 10 of Fig. 1A in a front view.

The filter element 10 is formed of a conventional filter material 20, such as cellulose acetate. Other filter materials known in the art can also be used. Filter material 20 may be wrapped in filter wrap (not shown). The filter element 10 has a circular-cylindrical shape. Similar shapes can also be used. The length of the filter element 10 (in the longitudinal direction L) can vary between about 5mm and 40mm, preferably between 6mm and 30mm. The diameter D of the filter element 10 can also vary between about 2mm and 15mm, preferably between 4mm and 10mm.

The filter element 10 includes a cavity (or channel) 30, which extends into the filter element 10 along the longitudinal direction L. The cavity 30 is devoid of filter material 20. The shape and size of the filter cavity may vary. The cavity 30 may have e.g. ex. the shape of a blind hole, as in Fig. 1A, and extend into the filter element to a certain depth, depending on the length of the filter element. Preferably, the depth of the cavity 30 is at least 1/3 of the length of the filter element 10. The cavity can also be circular-cylindrical. An internal diameter d may vary, depending on the diameter D of the filter element 10. The cross-sectional area of the cavity 30 should be at least 3mm2, preferably between 10mm2 and 30mm2. In other words, in case the cavity is circular-cylindrical, the diameter of the cavity should be at least 1 mm, preferably between 3 mm and 7 mm.

At least part of the inner surface of the cavity 30 is provided with an adsorbent 40. one or more adsorbents on the surface of cavity 30. Adsorbents can be selected, for example, from a group that includes activated carbon, zeolites, alumina, silica, silica gel, ion exchange resins, polyester resins, sepiolite, and species carbon, such as impregnated carbon, activated carbon fibers, or highly activated carbon. Suitable adsorbents and / or catalysts known in the art can be used to filter smoke or remove components from the smoke.

The adsorbent 40 can be applied to the internal surface of the filter element facing the cavity, the surface of which is formed by the filter material 20, by any suitable application technology.

Figure 2 is a schematic cross-sectional illustration of an exemplary filter element 110.

The filter element 110 of Fig. 2 differs primarily from the filter element 10 of Fig. 1A in that the cavity 130 now forms a channel that extends completely through the filter element 110, along the length of the longitudinal direction. Additionally, cavity 130 is provided with the adsorbent not only on part of its internal surface, but essentially on its entire surface.

Figures 3A and 3B are schematic cross-sectional illustrations of a first and second variant of an exemplary filter element 210 in accordance with the invention.

In contrast to filter elements 10, 110 according to Figs. 1 and 2, in the filter elements 210, 210 'according to Figs. 3A, 3B, cavity 130 is provided by a tube formed from tube material 50. The tube forms a single inner or central core of filter element 210, 210 ', said inner core being surrounded by filter material 20. Tube material 50 may be, for example, a paper material or a suitable polymeric material.

According to the first variant shown in Fig. 3A, the inner surface of the tube material facing the tube cavity is provided with an adsorbent 40.

On the contrary, according to the second variant shown in Fig. 3B, a first area of the inner surface of the tube material 50 facing the tube cavity is provided with a first adsorbent 40, while a second area of the The inner surface of the tube material facing the cavity is provided with a second adsorbent 40 ', different from the first adsorbent 40. The first area and the second area may partially overlap.

It goes without saying that the respective variants, which include different areas of the filter element surface facing the cavity that are provided with different adsorbents 40, 40 ', are also applicable with respect to Figs. 1, 2 previously described and to Figs. 4, 5. The number of different areas / different absorbents can vary and is not limited to two.

Preferably, the tube material 50 is self-supporting so that the tube can be formed in advance and has a predefined stability with respect to crushing. The thickness of the tube material 50, which defines the thickness of a tube wall, can vary, e.g. ex. between about 0.1mm and 1mm.

Figure 4 is a schematic cross-sectional illustration of an exemplary filter element 310.

This differs from the embodiments of Figs. 3A, 3B in that, in the filter element 310 the adsorbent 40 is not only applied to the inner surface of the tube material facing the tube, but the tube material 150 itself already includes the absorbent 40, that is, the Adsorbent 40 is embedded or embedded in tube material 150. Carbon paper would represent, for example, a respective tube material 150.

FIG. 5A is a schematic cross-sectional illustration of an exemplary filter element 410 according to a fifth embodiment. Figure 5B shows the filter element of Figure 5A in front view. The filter element 410 of Fig. 5 differs from the filter element 310 of Fig. 4 (and the other filter elements described above) in that a plurality of cavities or channels 230, 231, 231, 233 are included in filter element 410. The number of cavities or channels can vary, e.g. ex. between 1 and 5. When using a plurality of channels the sum of the surface areas of the channels can be increased, compared to when providing a single channel with the same cross-sectional area as the sum of the cross-sectional areas of the plurality of channels.

It goes without saying that also in the embodiments according to Figs. 1 to 3B a plurality of channels or cavities may be included in the respective filter elements.

Figure 6A is a schematic cross-sectional illustration of an exemplary smoking article, including the filter element of Fig. 4; Figure 6B is a schematic cross-sectional illustration of an exemplary smoking article, including the filter element of Fig. 4 as a first filter element and a variant of the filter element of Fig. 4 as a second filter element; and Figure 6C is a schematic cross-sectional illustration of an exemplary smoking article including the filter element of Fig. 2.

Figure 6A illustrates, in longitudinal view, a cigarette-shaped smoking article 80. The cigarette comprises a wrapped tobacco cylinder 60, including a quantity of a tobacco blend wrapped in cigarette paper (not shown), and a filter. The filter is comprised of filter elements 510 and 310, where filter element 310 is the filter element described above with reference to Fig. 4. Filter element 510 simply consists of a suitable filter material, e.g. ex. the filter material 20 discussed above, e.g. ex. cellulose acetate, which can be wrapped in filter wrap (not shown).

The filter 510, 310 is connected to the wrapped tobacco cylinder 60 by a tipping paper 70, which envelops the filter, that is, the filter elements 510, 310, and a portion of the wrapped tobacco cylinder 60. As shown in Fig. 6A, the filter can be designed as a filter having more than one segment, namely, filter elements 510, 310. The order of these filter elements can be changed, along the longitudinal direction of the smoking article. Additionally, any of the filter elements 10, 110, 210, 410, 510 may be used in place of the filter element 310 of the embodiment according to Fig. 6A.

The smoking article 180 shown in Fig. 6B differs from the smoking article according to Fig. 6A in that, instead of the filter element 510 (without cavity), a second inventive filter element 310 'forms part of the filter. . The filter element 310 'differs from the filter element 310 by the adsorbent 40' included in the tube material 150 ', which differs from the absorbent 40 included in the tube material 150 of the filter element 310. According to the present embodiment, different effects can be combined that can be achieved by different adsorbents. Apparently, more than two filter elements including different adsorbents can also be combined in this way. In this context, filter elements without tube material can also be used, as described eg. ex. with reference to Fig. 2, and / or filter elements where the adsorbent is only applied to the tube material (as shown in Fig. 3A).

As shown in Fig. 6C with respect to the smoking article 280, the filter may also comprise only one filter element, e.g. ex. filter element 110 according to FIG. 2 (or any other filter element described above). To achieve an effect similar to that achieved by the embodiment according to Fig. 6B, instead of the filter element 110 according to Fig. 1, a filter element as described with reference to Fig. 3B can be used, that is, a filter element in which different areas of the filter element surface facing the cavity or channel are provided with different adsorbents.

Although the present invention has been described in relation to what are presently considered practical exemplary embodiments, it should be understood that the invention is not limited to the disclosed embodiments, but rather is intended to cover various modifications and equivalent arrangements. which are included within the scope of the appended claims.

List of reference signs

elemento de filtro10, 110, 210,, 310,

filter element

20 filter material

30, 130, 230, 231, 233 cavity

40, 40 'adsorbent

50, 150, tube material

60 tobacco cylinder

70 nozzle paper

80, smoking article

L longitudinal direction

D, d diameter

Claims (10)

1. A filter element (10; 110; 210; 210 '; 310; 410; 510) for use in a smoking article (80), the filter element (10) being formed from a filter material (20 ), such as cellulose acetate, wherein the filter element (10) includes a cavity (30; 130) devoid of filter material (20), wherein the cavity (30; 130) forms a channel that extends completely through the filter element (10; 110), along a longitudinal direction (L) of the filter element (10; 110), wherein the channel (130) is a tube that is formed from a tube material (50; 150), said tube material being different from the filter material, wherein at least one internal surface of the tube material facing the tube cavity is at least partially provided with an adsorbent (40), wherein the tube is formed as a single central core of the filter element (210; 310). 2. The filter element (10) according to claim 1, wherein the adsorbent (40) is at least one of a group of adsorbents including activated carbon, zeolites, alumina, silica, silica gel, exchange resins ionic, polyester resins, sepiolite, and carbon species, such as impregnated carbon, activated carbon fibers, or highly activated carbon. The filter element (210; 310) according to claim 1 or 2, wherein the tube material (50; 150) is a paper material or a polymeric material. The filter element (310) according to any one of claims 1 to 3, wherein the tube material (150) includes the adsorbent (40). The filter element according to claim 4, wherein the tube material includes multiple layers, and wherein the innermost layer of the multiple layers facing the tube cavity includes the adsorbent. 6. The filter element (310) according to any one of claims 1 to 5, wherein the tube material (150) comprises or consists of carbon paper. The filter element according to any one of claims 1 to 6, wherein the filter element (410) includes a plurality of cavities (230; 231; 232; 233) lacking filter material (20), wherein a surface of the filter element facing at least one of the cavities (230; 231; 232; 233) is provided with the adsorbent (40). A smoking article (80; 180; 280) including a filter element (10; 110; 210; 210 '; 310; 410; 510) according to any one of claims 1 to 7. The smoking article (80) according to claim 8, comprising a wrapped tobacco cylinder (60) and a filter (510, 310) including the filter element (310), the cylinder (60) being connected ) of wrapped tobacco and the filter (510, 310) by a nozzle paper (70) that surrounds the filter (510, 310) and a part of the wrapped tobacco cylinder (60). The smoking article (180) according to claim 9, wherein the filter (310, 310 ') includes at least a first filter element (310) and a second filter element (310') according to any of claims 1 to 7, wherein a surface of the first filter element (310) facing the cavity of the first filter element (310) is provided with a first adsorbent (40), and wherein a surface of the second element Filter (310 ') facing the cavity of the second filter element (310') is provided with a second adsorbent (40 '), which is different from the first adsorbent (40).