KR20240074821A - Filter elements for mouthpieces for use with smoking products or HNB products - Google Patents

Abstract

The present invention relates to a filter element for a mouthpiece for use with smoking products or HNB products. The filter material has a filter main portion made of tow material, the tow material being formed from a plurality of individual threads made of cross-linked and pressed cellulose acetate filaments. The cellulose acetate filaments have a cross-sectional shape, in particular polygonal and preferably Y-shaped, and the tow material has a mass specific surface area of less than 0.15 m2/g, more particularly less than 0.3 m2/g and more than 0.025 m2/g.

Description

Filter elements for mouthpieces for use with smoking products or HNB products

The invention relates to filter elements for mouthpieces for use with smoking products or HNB products, as well as to the use of such filter elements in mouthpieces for smoking products or cigarette filters or mouthpieces for HNB products, respectively.

Depending on the application, mouthpieces for using smoking products have various functions. For example, a mouthpiece can act as a filter device that removes harmful components from the cigarette smoke stream, such as condensed substances, especially tar, as well as particulate matter contained in the smoke stream. This filtering function is particularly used in conventional tobacco applications. The corresponding mouthpiece can thereby be formed as an integral part of the cigarette or cigar and thus form a “tip” on the cigarette/cigar.

Examples of other types of mouthpieces relate to interchangeable devices such as replaceable filter elements that can be removed after use. This mouthpiece is accommodated in a suitable holder, for example a cigarette holder or pipe mouthpiece.

A mouthpiece formed as an integral part of a cigarette is a cigarette filter. Cigarette filters are intended to reduce the proportion of harmful substances such as condensate and gases in cigarette smoke. Additionally, filters make the smoke somewhat milder or more palatable to a large number of smokers. In conventional filter cigarettes, the filter is wrapped in a filter wrapper and connected to the tobacco stick via a so-called tipping paper, so most industrially manufactured cigarettes are equipped with filters.

There are various types of filter materials already in use, particularly to reduce substances in cigarette smoke before they reach the smoker's respiratory tract. However, in addition to removing large amounts of hazardous substances, a satisfactory filter must be effective so that excessive delay in the filter is not necessary without undesirably impeding the passage of air or smoke through the filter. However, when using a cigarette smoke filter, the material of the filter should not also change the taste of the cigarette smoke by adding its own flavor.

The invention relates not only to filter materials for the conventional tobacco applications described above, but in particular to filter materials and/or filter elements for mouthpieces used in smoking products, whereby such filter elements have a particularly simple filtering function. It has other functions.

In other applications, the filtering function does not imply priority for the mouthpiece. This applies, for example, to non-combustible heated products (“HNB products”), which have become increasingly popular in recent years. In these devices, a portion of the processed tobacco is heated by a heat source during use but is not combusted. The volatile components of tobacco, such as flavoring, nicotine, glycerin, and water, are thereby vaporized and introduced into the air that the user inhales through the HNB product. As the released material cools, an aerosol is formed and is inhaled by the user.

Commercially available HNB products are generally a device consisting of a filter on the inlet side, as well as a power supply supplying the heating element and a separate consumable product consisting of a part of the processed tobacco, a supporting element such as a tubular cellulose acetate segment. , arranged downstream along the direction of flow, and comprising so-called cooling elements, for example in the form of a pressed polylactide film bound into a cylinder with a plurality of axial channels. The consumable product is inserted into the device prior to use so that the heating element heats a portion of the tobacco when the HNB product is used.

For example, in the Philip Morris product called IQOS/HEETS, the tobacco portion is pierced by the device's heating blades. IQOS/HEETS Product means an IQOS device containing the related consumable HEETS product sold by Philip Morris. Consumable HEETS products are non-combustible heating products that only heat tobacco without burning it.

A competing product from BAT ("Glo") heats the cigarette externally, replacing the so-called cooling element with a tube. In these devices too, a portion of the processed tobacco is heated by a heat source during use but is not combusted. Volatile tobacco components such as flavoring, nicotine, glycerin, and water vaporize and enter the air that users inhale through HNB products. As the released material cools, an aerosol is formed and is inhaled by the user.

Consumable products known for this purpose have the disadvantage that the inlet filter can be significantly heated due to its proximity to the heating element and the hot vapors generated during use of the HNB product.

In so-called hybrid products, the aerosol generator is vaporized first (propylene glycol, glycerin); Cooling creates aerosols. This aerosol is transmitted through part of the processed tobacco and inhaled by the consumer. Additionally, even in this application, the mouthpiece has a special feature that prevents the user end from heating up to a degree that is unpleasant for the user.

In contrast to conventional tobacco products for burning tobacco, for HNB product consumables for elements disposed downstream of the heated tobacco portion in the direction of flow, such as cooling elements and inlet filters, substantially lower amounts of these components are formed. It may be desirable to have only a low filtering effect on condensed components of smoke such as tar.

In addition, the filter element must exhibit a selective filtration effect, especially for phenol, and must be able to reliably cool the heated particulate gas to reduce the temperature of the gas, aerosol or vapor inhaled by the user from the smoking product.

The invention relates not only to filter materials for the conventional tobacco applications described above, but in particular to filter materials and/or filter elements for mouthpieces used in smoking products, whereby such filter elements have a particularly simple filtering function. It has other functions.

The invention relates in particular to a filter element for a mouthpiece for use with a smoking product or HNB product, the filter element having a filter body made of a tow material, the tow material comprising a plurality of individual filaments of cross-linked and pressed cellulose acetate filaments. formed by, whereby the cellulose acetate filaments exhibit in particular a polygonal and preferably Y-shaped cross-sectional shape.

The tow material of the filter element of the invention should in particular have a mass-related specific surface area of less than 0.3 m ² /g, especially less than 0.15 m ² /g and more than 0.025 m ² /g. Mass-related specific surface area values, preferably between 0.3 m ² /g and 0.025 m ² /g, can significantly increase the performance and range of applications achievable with the filter element.

What was particularly recognized in this case was that the residual compression (RS) of the tow material of the filter body and the density of the filter body (Image) also have a significant impact on the performance of the filter element. Accordingly, the residual compression-related density value A is preferably at least 0.016 mg ² × mm ⁶ when:

Therefore, the residual compression (RS) of the tow material of the filter body should not exceed a value of 1.7, especially a value of 1.45, and therefore the residual compression (RS) of the tow material should be between about 1.05 and about 1.4, especially between 1.1 and 1.3. desirable.

According to an embodiment of the filter element of the invention, the filter body has a fiber weight of at most 10 mg/mm filter element length. The tow material constituting the base product for the manufacture of the filter elements of the invention should in particular exhibit a total fineness of 10,000 to 40,000 denier.

In particular, cellulose acetate filaments of tow material with a uniform filament fineness, which can be predefined or defined, are determined to be of particular interest. This predefined or definable uniform filament fineness is in particular in the range of 8 to 30 denier, preferably 9 to 30 denier, more preferably 10 to 20 denier.

The coefficient of variation of uniform filament fineness should be at most 0.1, preferably at most 0.05 and at most 0.01.

It is preferred that the individual filaments of the tow material formed from cellulose acetate filaments are predefined or can be defined and preferably exhibit a uniform filament fineness of at least 200 denier and at most 4000 denier, preferably at least 250 denier and at most 2500 denier, The coefficient of variation of the uniform filament fineness here is preferably at most 0.1, in particular at most 0.05 and at most 0.01.

A preferred embodiment of the filter element of the invention is provided in which the filter body is realized in particular as a filter rod and preferably has a diameter between approximately 8 mm and approximately 5 mm, in particular approximately 7.8 mm or approximately 5.35 mm.

Filter hardness is determined by pressing the flat end of a cylindrical rod with a diameter of 12 mm vertically against a horizontally positioned filter rod with a load of 300 g.

The minimum limit for Fitrona hardness is approximately 88% and is adjusted to market requirements. The filtrona hardness of the filter element can thereby be preferably set to approximately 88% to 95%, in particular approximately 90% to 93%.

A preferred embodiment of the filter element of the invention is provided wherein the filter body is realized in particular as a filter rod and preferably has a diameter between approximately 8 mm and approximately 5 mm, in particular approximately 7.8 mm or approximately 5.35 mm, wherein the filter body At least a portion of the packaging is made of paper or paper-like material.

The filtrona hardness of the filter element should preferably be greater than 85% in this embodiment, especially greater than 90%.

The configuration of the filter element of the invention provides for the filter body to have a fiber weight up to 10 mg/mm filter element length.

The cellulose acetate filaments of the tow material that serve as the base product for manufacturing the filter elements of the invention are in particular cellulose-2,5-acetate, cellulose butyrate, cellulose acetate butyrate, cellulose acetate propionate and/or cellulose propionate filaments. am. The cellulose acetate filaments preferably have a degree of substitution of approximately 1.5 to 3.0, preferably approximately 2.2 to 2.6.

The plasticizers preferably used in the plasticization, especially thermoplasticization, of cellulose acetate fibers and applied to the fibers may for example be selected from the following groups: glycerol esters (especially glycerol triacetate), ethylene and propylene carbonates, citric acid esters (especially acetyl citrate, triethyl citrate), glycose esters or diethylene glycol dibenzoate.

Additionally, it is preferred that the individual filaments of the tow material formed from cellulose acetate filaments may be predefined or defined and preferably exhibit a uniform filament fineness of at least 200 denier and at most 4000 denier, preferably at least 250 denier and at most 2500 denier. wherein the coefficient of variation of the uniform filament fineness is preferably at most 0.1, especially at most 0.05 to at most 0.01.

The present invention is based on the task of specifying a filter element for a mouthpiece for use with a smoking product or HNB product, where the filter element is suitable for a wide range of smoking product applications. Filter elements with a low resistance to suction and a low filtration performance are particularly mentioned, which sufficiently exhibit as consistent filter or hardness as possible when used in smoking products and which, nevertheless, allow the filter elements to be manufactured particularly economically.

The invention relates in particular to a filter element for a mouthpiece for use with a smoking product or HNB product, the filter element having a filter body made of a tow material, the tow material comprising a plurality of individual filaments of cross-linked and pressed cellulose acetate filaments. formed by, whereby the cellulose acetate filaments exhibit in particular a polygonal and preferably Y-shaped cross-sectional shape.

With this type of filter element, when the tow material exhibits the lowest possible mass-related specific surface area, sufficient filter hardness is achieved as well as the desired reduction in filtration performance, especially for condensable components such as tar, while maintaining overall tow material fineness. It was surprisingly found to be achievable.

The invention relates to filter elements for mouthpieces for use with smoking products or HNB products, as well as to the use of such filter elements in mouthpieces for smoking products or cigarette filters or mouthpieces for HNB products, respectively.

Smoking products in the sense of the present invention relate in particular to traditional tobacco products such as cigarettes, but also to pipes and marijuana products, so-called heat-not-burn (HNB) products, electronic cigarette products and so-called hybrid products.

In other applications, the filtering function does not imply priority for the mouthpiece. This applies, for example, to non-combustible heated products (“HNB products”), which have become increasingly popular in recent years. In these devices, a portion of the processed tobacco is heated by a heat source during use but is not combusted. The volatile components of tobacco, such as flavoring, nicotine, glycerin, and water, are thereby vaporized and introduced into the air that the user inhales through the HNB product. As the released material cools, an aerosol is formed and is inhaled by the user.

Commercially available HNB products are generally a device consisting of a filter on the inlet side, as well as a power supply supplying the heating element and a separate consumable product consisting of a part of the processed tobacco, a supporting element such as a tubular cellulose acetate segment. , arranged downstream along the direction of flow, and comprising so-called cooling elements, for example in the form of a pressed polylactide film bound into a cylinder with a plurality of axial channels. The consumable product is inserted into the device prior to use so that the heating element heats a portion of the tobacco when the HNB product is used.

For example, in the Philip Morris product called IQOS/HEETS, the tobacco portion is pierced by the device's heating blades. IQOS/HEETS Product means an IQOS device containing the related consumable HEETS product sold by Philip Morris. Consumable HEETS products are non-combustible heating products that only heat tobacco without burning it.

A competing product from BAT ("Glo") heats the cigarette externally, replacing the so-called cooling element with a tube. In these devices too, a portion of the processed tobacco is heated by a heat source during use but is not combusted. Volatile tobacco components such as flavoring, nicotine, glycerin, and water vaporize and enter the air that users inhale through HNB products. As the released material cools, an aerosol is formed and is inhaled by the user.

Consumable products known for this purpose have the disadvantage that the inlet filter can be significantly heated due to its proximity to the heating element and the hot vapors generated during use of the HNB product.

In so-called hybrid products, the aerosol generator is vaporized first (propylene glycol, glycerin); Cooling creates aerosols. This aerosol is transmitted through part of the processed tobacco and inhaled by the consumer. Additionally, even in this application, the mouthpiece has a special feature that prevents the user end from heating up to a degree that is unpleasant for the user.

In contrast to conventional tobacco products for burning tobacco, for HNB product consumables for elements disposed downstream of the heated tobacco portion in the direction of flow, such as cooling elements and inlet filters, substantially lower amounts of these components are formed. It may be desirable to have only a low filtering effect on condensed components of smoke such as tar.

The present invention is based on the task of specifying a filter element for a mouthpiece for use with a smoking product or HNB product, where the filter element is suitable for a wide range of smoking product applications. Filter elements with a low resistance to suction and a low filtration performance are particularly mentioned, which sufficiently exhibit as consistent filter or hardness as possible when used in smoking products and which, nevertheless, allow the filter elements to be manufactured particularly economically.

In addition, the filter element must exhibit a selective filtration effect, especially for phenol, and must be able to reliably cool the heated particulate gas to reduce the temperature of the gas, aerosol or vapor inhaled by the user from the smoking product.

These and other problems are solved by the subject matter of independent claim 1.

Accordingly, the present invention relates in particular to a filter element for a mouthpiece for use with a smoking product or HNB product, the filter element having a filter body made of a tow material, the tow material comprising a plurality of cross-linked and pressed cellulose acetate filaments. It is formed by individual filaments, whereby the cellulose acetate filaments exhibit in particular a polygonal and preferably Y-shaped cross-sectional shape.

With this type of filter element, when the tow material exhibits the lowest possible mass-related specific surface area, sufficient filter hardness is achieved as well as the desired reduction in filtration performance, especially for condensable components such as tar, while maintaining overall tow material fineness. It was surprisingly found to be achievable.

The tow material of the filter element of the invention should in particular have a mass-related specific surface area of less than 0.3 m ² /g, especially less than 0.15 m ² /g and more than 0.025 m ² /g. Mass-related specific surface area values, preferably between 0.3 m ² /g and 0.025 m ² /g, can significantly increase the performance and range of applications achievable with the filter element.

According to a preferred embodiment of the filter element of the invention, the cellulose acetate filter element of tow material is at least partially tri-lobed; In other words, it has a star-shaped cross-sectional shape with three arms. This cross-sectional shape is very suitable when the cellulose acetate filaments must have the largest possible specific surface area to enable high filtration capacity - as in the case of conventional cigarettes - with simultaneous economical use of raw materials. Alternatively, it is possible to achieve the desired large specific surface area using, for example, bundles of extremely fine filaments of circular cross-section. However, other cross-sectional shapes for the cellulose acetate filaments are also conceivable, for example polygonal or four-sided cross-sectional shapes.

The tow material of the filter element of the present invention is formed from continuous stuffer box-pressed cellulose acetate filaments. A solution of about 30% cellulose-2,5-acetate in acetone is thereby compressed through the spinneret, the acetone is evaporated in the spinning chamber, and a plurality of cellulose acetate filaments are gathered into strips and then pressed in a stuffer box. The product is then dried and usually compressed into packages. Tow material (“filter tow”) is removed from the bale and processed into filter rods on a filter rod machine. Accordingly, the filter tow is stretched in a stretching device, provided with additives that bind the cellulose acetate filaments, forming the so-called rovings, and then compressed cross-axially, optionally wrapped in paper as well as cut to the final length of the filter element. .

By selecting a mass-related specific surface area for the tow material of the filter element of the invention in particular in the range of less than 0.3 m ² /g, especially less than 0.15 m ² /g and more than 0.025 m ² /g, the desired reduced filtration for condensable components. It is possible to achieve filter elements that achieve performance while still achieving sufficient filter hardness while maintaining total fineness.

According to an embodiment of the filter element of the invention, the cellulose acetate filaments of the individual filaments of tow material are at least partially formed as hollow and/or tubular cellulose acetate filaments.

In particular, what is to be understood by hollow/tubular cellulose acetate filaments are preferably cylindrical filaments which, when viewed in cross section, exhibit one or more continuous cavities.

These hollow fibers may be designed, at least in part, as multi-lumen hollow fibers. Compared to “solid” cellulose acetate filaments, single-lumen or multi-lumen tubular cellulose acetate filaments are much more resistant to twisting, making it possible to achieve particularly high fitrona hardnesses without increasing material compression.

According to embodiments of the invention, the hollow cellulose acetate filaments are at least partially trilobal; In other words, it has a star-shaped cross-sectional shape with three arms. This cross-sectional shape is very suitable when the cellulose acetate filaments have the largest possible specific surface area, enabling for example high filtration capacities with simultaneous economical use of raw materials.

Alternatively, it is possible to achieve the desired large specific surface area using, for example, bundles of extremely fine filaments of circular cross-section. However, other cross-sectional shapes for the cellulose acetate filament are also conceivable, for example a four-sided cross-sectional shape.

The filter element of the invention comprises a filter body that may be based at least in part on cellulose acetate filaments, at least partially formed of hollow cellulose acetate filaments, such that the filaments of the filter element at least partially formed of hollow cellulose acetate filaments have an overall fiber volume of Because the external surface area is small, low suction resistance and low filtration performance can be realized.

In this context, it has surprisingly been discovered that particularly high filtrona hardnesses can be realized with filter elements, in part because the filaments are formed from hollow cellulose acetate filaments.

In practice, it has become clear that filter elements made at least partially from hollow cellulose acetate filaments (hollow fibers) achieve the desired minimum filtrona hardness at lower fiber weight per unit volume.

Since the filter element of the present invention is based on cellulose acetate filaments, the filter element of the present invention is designed to form a uniform, white and smooth entrance leaflet against the tobacco rod of, for example, a cigarette, thereby providing an additional selective phenol filtration effect. It can be realized.

First of all, the use of filter elements based on cellulose acetate filaments makes it possible to produce filter rods especially for cigarettes, which exhibit clearly superior properties compared to specific retention phenomena from a smoking and health point of view.

Therefore, filters made of cellulose acetate filter out condensate and harmful nitrosamines and phenols much more efficiently than nicotine. Additionally, smokers rate the flavors of today's common cigarette blends such as "American Blend", "German Blend" and "Virginia" combined with filter rods made of cellulose acetate as most palatable. Another advantage of cellulose acetate filter rods that cannot be underestimated is the optical homogeneity of the filter cut surface.

With the filter elements of the invention being made of hollow cellulose acetate filaments functioning at least partially as filler according to embodiments, there can be a wide range of variable resistance to draw and filtration performance in filter rods made from the materials of the invention.

In particular, filter materials composed at least partially of hollow cellulose acetate filaments have been shown to exhibit improved thermal cooling effectiveness. The use of hollow cellulose acetate filaments as filler still results in a very low filtration effect for suspended solids and gases to be removed; In other words, it was decided that a retention effect could be achieved.

It is assumed that this effect is achieved due to the surface or flow of the gas or air to be cleaned being modified by the hollow cellulose acetate filaments in a way that retains only minor amounts of any potential suspended solids in the gas/air. Another reason may be that the use of hollow cellulose acetate filaments can achieve different and particularly advantageous filter material surface structures.

The filter element of the invention also enables specific variable cooling of heated particulate gases (in particular aerosols) such that the temperature of the gas, aerosol or vapor inhaled by the user of the smoking product or HNB product can be selectively reduced. It has the advantage of By varying the proportion of hollow cellulose acetate filaments in the filter and/or filler, the desired cooling effect can be specifically tailored to the application.

What is further important to note is that there is essentially no flow in the filter element of the invention through the hollow cellulose acetate filaments (=hollow fibers). From geometric considerations, it is clear that the inter-fiber distance is much larger than the lumen (empty part) of the hollow fiber. The viscosity of the aerosol (effectively air) then creates the path of least resistance (i.e., flow between filaments rather than through each individual filament).

In other words, because there is no flow through the hollow cellulose acetate filaments in the tow material, the operating filtration surface is never maximized in embodiments of the filter element of the present invention.

In particular, the hollow cellulose acetate filaments can thus have a twist that closes the lumen of the hollow cellulose acetate filaments without affecting the performance of the filter and/or filler of the invention with respect to the set target parameters.

What should be particularly noted in this regard is that the hollow cellulose acetate filaments realized as hollow fibers need not be continuously hollow, but rather may be partially closed by twisting. It may also deviate from the ideal circular shape.

Embodiments of the invention provide that the hollow cellulose acetate filaments of the tow material serve on the one hand as a support material and on the other hand as a cooling material. With the hollow cellulose acetate filaments simultaneously serving as support material, a particularly compact filter element can be realized, thereby eliminating the need to increase the size of the smoking product.

As used herein, the term “Filtrona hardness” refers to filter hardness determined according to the Filtrona principle. According to this principle, the filter hardness is determined by pressing the flat front end of a cylindrical rod with a diameter of 12 mm vertically on a horizontally positioned filter rod with a load of 300 g. The ratio of the compressed diameter to the predetermined initial diameter at first contact yields the filtrona hardness percentage.

Filter element or filter rod hardness are respectively important target criteria, especially for cigarette filters. It is usually expressed in so-called filtrona longitude. It should be noted here that filtrona hardness is measured only on filter elements, but on the base (original) filter material; That is, it is not measured in tow material. The filtrona hardness of the filter element is particularly influenced by the amount of triacetin that is or may be sprayed onto the filter element.

The minimum limit for Fitrona hardness is approximately 88% and is adjusted to market requirements. The filtrona hardness of the filter element can thereby be preferably set to approximately 88% to 95%, in particular approximately 90% to 93%.

A preferred embodiment of the filter element of the invention is provided wherein the filter body is realized in particular as a filter rod and preferably has a diameter between approximately 8 mm and approximately 5 mm, in particular approximately 7.8 mm or approximately 5.35 mm, wherein the filter body At least a portion of the packaging is made of paper or paper-like material.

The filtrona hardness of the filter element should preferably be greater than 85% in this embodiment, especially greater than 90%.

Filtrona hardness is specifically determined by the fiber weight per volume for a given filter diameter, and the filament fineness of the cellulose acetate filaments of the tow material has a minor effect on Filtrona hardness.

The configuration of the filter element of the invention provides for the filter body to have a fiber weight up to 10 mg/mm filter element length.

Filter element hardness can also be achieved by using stronger filter wrappers or stronger tipping papers.

Tipping paper is paper with multiple filter elements joined together or with filter elements connected to a tobacco stick. However, increasing the filtration or hardness of the filter element by using stronger filter wrappers or stronger tipping papers has an economic disadvantage as higher costs can be expected.

The filtrona hardness of the filter element is related to so-called “hot decay”, in which the filter hardness decreases as the filter element is used, i.e. used with smoking products or HNB products. This phenomenon can occur in traditional cigarettes, especially when the filter element heats up in the presence of moisture during the last puff, but this undesirable effect can also occur in HNB products.

In this context, when using tow materials with a quoted mass-related specific surface area of less than 0.15 m ² /g as the base material of the filter element of the invention, the degree of degradation of the filtrona hardness due to the phenomenon of “hot collapse” is significantly reduced. It turns out that it can be done.

By means of the tow material of the filter body of the filter element of the invention having a mass-related specific surface area in the range between 0.3 m ² /g and 0.025 m ² /g, especially less than 0.15 m ² /g, without reducing the length of the filter element. The suction resistance and filtration performance of the filter element of the present invention can be reduced. Relatively long filter elements that enable correspondingly long cooling sections can thus be realized, which is advantageous compared to the heat balance, especially when the filter elements are used in conjunction with HNB products.

In addition, the specification of the present invention for a mass-related specific surface area of the tow material in particular to a value of less than 0.15 m ² /g without reducing the fiber weight of the filter element per volume fraction and/or without reducing the total fineness of the tow material. This allows the suction resistance and filtration performance of the filter element to be reduced. This has the advantage that the filter or hardness of the filter element does not decrease due to a reduction in the total fineness and/or a reduction in the fiber weight of the filter element per volume fraction.

According to an embodiment of the filter element of the invention, the filter body has a fiber weight of at most 10 mg/mm filter element length. The tow material constituting the base product for the manufacture of the filter elements of the invention should in particular exhibit a total fineness of 10,000 to 40,000 denier.

The cellulose acetate filaments of the tow material that serve as the base product for manufacturing the filter elements of the invention are in particular cellulose-2,5-acetate, cellulose butyrate, cellulose acetate butyrate, cellulose acetate propionate and/or cellulose propionate filaments. am. The cellulose acetate filaments preferably have a degree of substitution of approximately 1.5 to 3.0, preferably approximately 2.2 to 2.6.

The plasticizers preferably used in the plasticization, especially thermoplasticization, of cellulose acetate fibers and applied to the fibers may for example be selected from the following groups: glycerol esters (especially glycerol triacetate), ethylene and propylene carbonates, citric acid esters (especially acetyl citrate, triethyl citrate), glycose esters or diethylene glycol dibenzoate.

A person skilled in the art is familiar with the amount of plasticizer and/or water-soluble binder used. Typically the plasticizer and/or binder content is about 1 to 14 weight percent; However, in special cases the plasticizer content can easily exceed this range.

Water-soluble binders that are preferentially present on the surface of the cellulose acetate filaments are, in particular, individual filaments of the tow material or polyalkylene oxides, water-soluble esters or ethers, starch, starch derivatives, p-polyvinyl alcohol, polyvinyl ether, p-polyvinyl acetate. and/or high boiling point solvents applied to tow materials such as polysaccharides, water-soluble polyamides and polyacrylates.

What was particularly recognized in this case was that the residual compression (RS) of the tow material of the filter body and the density of the filter body (Image) also have a significant impact on the performance of the filter element. Accordingly, the residual compression-related density value A is preferably at least 0.016 mg ² × mm ⁶ when:

Therefore, the residual compression (RS) of the tow material of the filter body should not exceed a value of 1.7, especially a value of 1.45, and therefore the residual compression (RS) of the tow material should be between about 1.05 and about 1.4, especially between 1.1 and 1.3. desirable.

Residual compression is therefore understood as the ratio of the length of the final pressed cellulose acetate filament to the length of the filter element. Residual compression is an inherent characteristic for a given filter element.

A further aspect of the present invention relates to specifying a tow material for providing a filter element for a mouthpiece to be used with a smoking product or HNB product, wherein the tow material provides the most consistent performance possible, particularly with regard to filtration performance and filter hardness. The effectiveness of filter elements produced from tow materials is optimized.

In this context, the cellulose acetate filaments of the tow material are determined to be of particular importance, especially with a uniform filament fineness that is or can be defined in advance. This predefined or definable uniform filament fineness is in particular in the range of 8 to 30 denier, preferably 9 to 30 denier, more preferably 10 to 20 denier.

In order to achieve consistent performance of filter elements made of tow material, especially with regard to filtration performance and filter hardness, the coefficient of variation of uniform filament fineness should be at most 0.1, preferably at most 0.05 and at most 0.01.

The coefficient of variation of uniform filament titer, which may also be referred to as the coefficient of variation, is a statistical parameter and - in contrast to dispersion - characterizes a measure of relative dispersion; That is, it does not depend on the unit of measurement of the statistical or random variable.

That is, during the production of tow material, it is ensured that the individual filaments produced by the spinning projections of each used spinning frame exhibit uniform filament fineness.

Therefore, each spinneret of the spinning frame is assigned itself to a specific frequency-controlled spin pump, in order to ensure that each spinneret is supplied with spinning fluid (a solution of approximately 30% cellulose-2,5-acetate in acetone). This can be practically realized by means of a spinneret, enabling the realization of a uniform nozzle pressure and a uniform flow rate of the spinning fluid delivered from each spinneret per unit time.

This easily realizable yet effective approach makes it possible to achieve particularly predefined or definable uniform filament fineness.

Alternatively or additionally, individual filaments of tow material formed from cellulose acetate filaments may be predefined or defined and preferably have a uniform filament fineness of at least 200 denier and at most 4000 denier, preferably at least 250 denier and at most 2500 denier. wherein the coefficient of variation of the uniform filament fineness is preferably at most 0.1, in particular at most 0.05 and at most 0.01.

Claims (15)

A filter element for a mouthpiece for use with a smoking product or HNB product, the filter element having a filter body made of a tow material, the tow material being formed by a plurality of individual filaments of cross-linked and pressed cellulose acetate filaments. wherein the cellulose acetate filaments exhibit a particularly polygonal, preferably Y-shaped cross-sectional geometry, and the tow material has a mass of less than 0.3 m ² /g, especially less than 0.15 m ² /g and more than 0.025 m ² /g. A filter element having an associated specific surface area. According to paragraph 1,
A filter element in which the tow material of the filter body exhibits a residual compression (RS) and a density (Image), wherein the residual compression-related density value A amounts to at least 0.016 mg ² × mm ⁶ .

. According to claim 1 or 2, especially clause 2,
wherein the residual compression (RS) of the tow material of the filter body does not exceed a value of 1.7, and the residual compression (RS) of the tow material of the filter body is preferably between approximately 1.1 and approximately 1.7, especially 1.3. A filter factor between 1.7 and 1.7. Filter according to claim 1 , in particular 2 or 3 , wherein the filter body exhibits a fiber weight, wherein the fiber weight of the filter body amounts to at most 10 mg/mm filter length. Element. According to any one of claims 1 to 4,
The cellulose acetate filaments of the tow material may in particular have a predefined or definable uniform filament fineness, in particular between 8 denier (8.88 dtex) and 30 denier (33.33 dtex), preferably between 9 denier (10 dtex) and 30 denier (33.33 dtex). dtex), more preferably a filter element exhibiting a predefined or definable uniform filament fineness within the range between 10 denier (11.11 dtex) and 20 denier (22.22 dtex). According to clause 5,
A filter element wherein the coefficient of variation of the uniform filament fineness is at most 0.1, preferably at most 0.05 to at most 0.01. According to any one of claims 1 to 6,
Said individual filaments of tow material formed from said cellulose acetate filaments have a particularly pre-fine thickness of at least 200 denier (222 dtex) and at most 4000 denier (4.444 dtex), preferably at least 250 denier (277 dtex) and at most 2500 denier (2.777 dtex). A filter element exhibiting a defined or definable and preferably uniform filament fineness. In clause 7,
A filter element wherein the coefficient of variation of the uniform filament fineness is at most 0.1, preferably at most 0.05 to at most 0.01. According to any one of claims 1 to 8,
The filter body is in particular realized as a filter rod and preferably has a diameter between approximately 8 mm and approximately 5 mm, in particular approximately 7.8 mm or approximately 5.35 mm, and at least a part of the filter body is wrapped in paper or paper-like material. filter element. According to clause 9,
A filter body with packaging consisting of paper or paper-like material, when a cylindrical test piece with a mass of 300 g and a diameter of 12 mm is placed at the front end of the filter body perpendicular to the axis of the filter body, has a thickness of less than 0.90 mm, especially 0.85 mm. A filter element with a compression depth less than According to clause 9,
A filter body without packaging consisting of paper or paper-like material has a compression of less than 0.90 mm, especially less than 0.85 mm, when a cylindrical test piece with a mass of 300 g and a diameter of 12 mm is placed at the front end of the filter body perpendicular to the axis of the filter body. Filter element with depth. According to any one of claims 1 to 11,
The filter element of claim 1, wherein the cellulose acetate filaments of the individual filaments of tow material are at least partially formed of hollow and/or tubular cellulose acetate filaments. According to any one of claims 1 to 12,
A filter element wherein the hardness of the filter body is at least 80% Fitrona hardness, preferably at least 90% Fitrona hardness. According to any one of claims 1 to 13,
The filter body has a plasticizer content representing a plasticizer content of about 2% to about 15%, preferably about 4% to 10%, the plasticizer being in particular triacetin, triethylene glycol diacetate and/or citric acid diethyl ester. Containing filter elements. According to any one of claims 1 to 14,
The tow material exhibits a total fineness of between 4000 denier (4.444 dtex) and 40000 denier (44.444 dtex), preferably between 6000 denier (6.667 dtex) and 30000 denier (33.333 dtex).