JP7407944B2 - Filter materials and/or filler materials for mouthpieces for use in smoking or HNB products, mouthpieces and cigarette filters comprising such filter materials and/or filler materials, and such filter materials and/or fillers Method for manufacturing materials - Google Patents

Description

The present invention provides filter materials and/or filler materials for mouthpieces for use in smoking or HNB products, as well as such filter materials and/or filler materials in cigarette filters or mouthpieces for smoking product mouthpieces or HNB products. or regarding the use of filler materials. According to a further aspect, the invention relates to a method for manufacturing such filter and/or filler materials.

Smoking products in the sense of the present invention relate to conventional tobacco products, in particular cigarettes, but also to pipes and marijuana products, as well as so-called heated tobacco (HNB) products, vaping products and so-called hybrid products.

Mouthpieces for smoking products have different functions depending on their use. Firstly, the mouthpiece can act as a filtering device for attracting harmful elements, such as condensed substances, such as tar, together with particulate matter that accompanies the flow of tobacco smoke from the smoke. This filtering function is particularly used in traditional tobacco applications. Thereby, the corresponding mouthpiece can be formed as an integral part of the cigarette or cigarillo, thus forming a "tip" on the cigarette or cigarillo.

A replaceable device is another type of mouthpiece, for example a replaceable filter element that can be removed after use. Such a mouthpiece is housed in a suitable holder, for example a cigarette holder or a pipe mouthpiece.

One mouthpiece that is 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. Filters also make the smoke somewhat milder or more palatable to most smokers. In conventional filter cigarettes, the filter is wrapped in filter wrap paper and connected to the tobacco roll with a so-called tipping paper, whereby most industrially produced cigarettes are provided with a filter. Those who roll their own can purchase them at tobacco stores.

In particular, many types of filter materials are already in use to reduce the levels of substances contained in tobacco smoke before it reaches the smoker's respiratory system. However, in addition to removing large amounts of harmful elements, a satisfactory filter will not undesirably impede the passage of air or smoke through the filter and will therefore be effective without requiring excessive drag on the filter. There is also a need. However, when used in tobacco smoke filters, the filter material must not alter the taste of tobacco smoke by adding unique flavors.

A further important factor in the manufacture of a satisfactory tobacco smoke filter is that its manufacture is not too complex so as not to unduly increase the final price of the smoking product in which the filter is used.

However, the present invention is not a filter material for the conventional tobacco applications mentioned above, but in particular a filter material and/or filler material for a mouthpiece used in a smoking product that has other functions than just a filtering function. Regarding.

In other applications, the filtering function of the mouthpiece is not really the main focus. This applies, for example, to heated tobacco products ("HNB products"), which have become increasingly popular in recent years. In these devices, the processed tobacco portion is heated by a heat source during use, but is not combusted. Volatile tobacco components such as flavoring agents, nicotine, glycerin, and water are thereby vaporized and entrained in the air that the user inhales through the HNB product. When the emitted substance cools, it forms an aerosol that is inhaled by the user.

Commercially available HNB products consist of a cylinder with a power supply supplying the heating element, a separate consumable consisting of a processed tobacco section, a support element such as a tubular cellulose acetate segment, and a number of axial channels and a mouth filter. and a so-called cooling element arranged downstream in the machine direction, such as in the form of a crimped polylactide film bundled into a shape. The consumable is inserted into the device prior to use so that the heating element heats the tobacco portion during use of the HNB product.

For example, in a Philip Morris product called IQOS/HEETS, the tobacco portion is penetrated by a heated blade within the device. IQOS/HEETS products refer to IQOS devices with accompanying consumable HEETS products sold by Philip Morris. Consumable HEETS products are heated tobacco products in which the tobacco is simply heated without being burned.

In BAT's competing product ("Glo"), the tobacco is heated externally and the so-called cooling element is replaced by a tube. In these devices, too, the processed tobacco portion is heated by a heat source during use, but is not combusted. Volatile tobacco components such as flavoring agents, nicotine, glycerin, and water are thereby vaporized and entrained in the air that the user inhales through the HNB product. When the emitted substance cools, it forms an aerosol that is inhaled by the user.

Known consumables for this application have the disadvantage that the mouth filter can become very hot due to its proximity to heat generating elements and due to the high temperature steam generated during use of the HNB product. be.

In so-called hybrid products, an aerosol generator is first vaporized (propylene glycol, glycerin) and upon cooling generates an aerosol. This aerosol passes through the processed tobacco portion and is inhaled by the consumer. Even in such applications, the mouthpiece has the particular function of keeping the user-facing end from becoming uncomfortably hot for the user.

In contrast to conventional tobacco products, which burn tobacco, in the case of HNB product consumables, elements placed downstream of the heated tobacco section, such as cooling elements and mouth-side filters, do not burn tar or other consumables. Regarding the condensed components, it may be desirable to have only a low filtering effect, since these smoke components may occur in substantially small amounts.

Accordingly, the materials required to form mouthpieces for smoking products need to be particularly compatible, matching the physical properties (temperature, flow profile, etc.) and chemical composition of the smoke. Both conventional cigarette filters and HNB products in particular have a number of target parameters that need to be adjusted or respectively met by proper selection and construction of mouthpiece materials. This is particularly relevant to the following target parameters, which are briefly explained below.
・Suction resistance ・Filtration performance ・Filter rod hardness/Filtrona hardness ・Appearance ・Manufacturing cost effectiveness ・Smoke temperature

Filter rod hardness is an important target criterion for cigarette filters. This is usually indicated as the so-called Filtrona hardness. The Filtrona hardness is determined by pressing the flat front end of a 12 mm diameter cylindrical rod vertically against a horizontally arranged filter rod with a load of 300 g. The ratio of the compressed diameter to the initial diameter predetermined at first contact yields the Filtrona hardness percentage.

It should be emphasized that Filtrona hardness is measured only on the filter and not on the underlying (raw) filter material.

The lower limit of Filtrona hardness is approximately 88% and is adjusted to market requirements. Thereby, the Filtrona hardness of the cigarette filter can preferably be set to about 88% to 95%, in particular about 90% to 93%.

In conventional cigarette filters, the Filtrona hardness is essentially determined by the fiber weight per unit volume for a given filter diameter. In particular, filament titer has only a small effect on Filtrona hardness.

In some cases, stronger filter wrap papers or stronger tip papers also achieve higher Filtrona hardness. Tipping paper is paper in which multiple filter elements are connected together or a filter element is connected to a tobacco rod. However, increasing the filtrona hardness by using stronger filter wrap paper or stronger chipping paper is economically disadvantageous as this approach can be expected to be more costly.

Related to Filtrona hardness is the so-called "hot collapse", where the filter hardness decreases during smoking. In conventional cigarettes, this can occur especially if the filter is heated in the presence of moisture during one of the last puffs. This undesirable result can also occur with HNB products.

In addition to a filtrona hardness that is as constant and high as possible in the use of the smoking product, the material of the mouthpiece should also exhibit a predefined or definable filtration performance. Filtration performance with respect to condensate (droplets, particles) (also referred to as condensate or tar) is of concern for conventional tobacco products and HNB products because condensate contains several unhealthy substances.

In conventional products, filtration performance (along with other influencing factors such as tobacco blend, ventilation, etc.) is selected to adjust the ``delivery'' of the cigarette (the level of smoke components within the mainstream smoke). In many markets, laws and regulations set limits on "delivery." Below legal caps, ``delivery'' can be tailored to consumer preferences.

With HNB products, the aerosol contains much less condensate that has negative health effects than with conventional products. However, since more desirable substances such as flavor substances and nicotine are present in the condensate as well, the aim here is to choose the lowest possible filtration performance without reducing it to zero.

It should be noted with respect to the target parameter of "draw resistance" that consumers prefer a certain range of draw resistance when using tobacco products. In conventional cigarettes, the filter serves to regulate the draw resistance of the cigarette (in addition to regulating "delivery").

However, in HNB products, the draw resistance provided by the oral filter (mouthpiece) is possible because other components of the HBN device, especially the tobacco heating part and the device, already provide a high contribution to the draw resistance. The trend should be as low as possible. The low suction resistance of the filter (mouthpiece) provides freedom in relation to other components of the HBN device. This is desirable.

However, suction resistance and filtration performance are closely related. Both can be reduced in multiple ways, but this often has a negative impact on other parameters.

For example, by shortening the filter length, suction resistance and filtration performance can be reduced. However, when the filter length becomes smaller than the filter diameter, processability becomes a problem. Shorter filters also shorten the cooling section, creating problems with heat balance.

Alternatively or in addition, suction resistance and filtration performance can be reduced by reducing the fiber weight in the filter material per volume content and/or total denier. However, this has the disadvantage that the filtrona hardness may be reduced and the minimum hardness may no longer be achieved.

Alternatively or in addition, suction resistance and filtration performance can be reduced by increasing filament titer. For a fixed filter diameter and a given fiber weight per unit volume, filtration performance and suction resistance decrease with increasing filament titer. This is desirable for HNB products compared to conventional products. As mentioned above, the Filtrona hardness is only slightly dependent on the titer of the filament, so the hardness is not adversely affected either.

It is noteworthy with respect to the target parameter of "appearance" that consumers prefer mouthpieces with a flat, white cross-sectional area on the oral side. However, some products have a tube-shaped opening.

The thing to note about smoke temperature is that smoke temperature does not pose a problem in today's conventional products. However, commercially available HNB products have significantly higher smoke temperatures, uncomfortably high for some consumers. Additionally, commercial HNB products require refrigeration to cool the vaporized components such that an aerosol of the gaseous components is first formed.

For commercially available HNB products, the distance from the heating element to the mouth end of the HNB product is probably the most important parameter for cooling the aerosol. Thus, for example, it is known to arrange so-called cooling elements downstream of the tobacco part and the support element. The cooling element can be in the form of a crimped polylactide film or in the form of a cardboard tube, so that this element, especially located downstream of the tobacco part and the support element, provides mechanical stability in addition to cooling. Also responsible for the function of the spacer provided.

Finally, the mouthpiece material must meet cost-effectiveness target parameters. In particular, there is a need for suitable mouthpiece materials that can be produced with the lowest possible material usage and lowest possible processing costs.

Conventional cigarette filters, usually composed of cellulose acetate filaments, ensure optimal filtration of components in the smoke, but these filter materials can be used in other applications, especially in the case of HNB products or e-cigarettes. It is often of limited use. This is because these applications require the filter material or the respective mouthpiece material to perform other functions.

HNB products and conventional smoking products generally have the disadvantage that users inhale inhaled aerosols at high temperatures. This can be unpleasant for users. Therefore, especially in the case of HNB products, the mouthpiece material serves to cool the aerosol with the lowest possible filtration performance.

Also, in the case of conventional cigarettes, especially so-called slim or ultra-slim cigarettes (i.e. cigarettes with a small diameter of e.g. 5.0 mm to 6.5 mm), the filter material/mouthpiece material is compared to the filter material of a king size cigarette. They should provide reduced filtration performance, improved cooling, and improved tactile properties (a firm but not too hard grip). Naturally, there is less smoke/flavor during combustion than a king size cigarette. Low filtration performance is required to avoid further deterioration of flavor. Merely reducing the amount of filter material for that purpose will eventually result in insufficient hardness of the filter.

With the same fiber density, filters for slim or ultra-slim cigarettes have significantly higher draw resistance than king-size filters, which is generally undesirable.

For both HNB products and ultra-slim cigarettes, it is proposed to increase the filament titer while maintaining the total titer in order to achieve the desired reduction in filtration performance in terms of condensable components such as tar and sufficient filter hardness. ing. However, this approach has the disadvantage that such fiber materials of high filament titer are economically disadvantageous on conventional spinning machines. In conventional filter tow production, a solution of approximately 30% cellulose-2,5-acetate in acetone is extruded through a spinneret, the acetone is evaporated by blowing heated air in a spinning chamber, and then a number of filaments ( 1,000 to 35,000) are collected to form a strip and crimped in a stuffer box. For higher filament titers, a larger amount of solvent needs to be evaporated per filament, which in this case takes more time and requires a slower spinning speed due to the larger ratio of cross-sectional area to surface area of the filament. bring.

Based on this problem, the present invention is based on the challenge of identifying materials suitable for a wide range of smoking product applications.

In particular, the invention is based on the problem of identifying a filter material with low suction resistance and low filtration performance, which filter material has a sufficiently high filtrona hardness that is as constant as possible when used in smoking products. can be achieved and the filter material can nevertheless be produced particularly economically.

Furthermore, the filter material is suitable for producing filters with a uniform, white, flat front end on the oral side.

It is further desirable in this context that the filter material exhibits a selective filtration effect towards phenol.

The filter material is particularly suitable for ensuring cooling of heated particle-containing gases so that the user can reduce the temperature of the gas, aerosol, or vapor that is drawn from the smoking product.

Furthermore, this material is suitable, especially when used as filter material for slim or ultra-slim cigarettes, to be able to achieve adjustable suction resistance, and especially a reduced one compared to king size filters. It is.

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

The invention therefore particularly relates to a material for forming a mouthpiece for a smoking product, comprising a filler material based on cellulose acetate filaments, at least in part formed as hollow cellulose acetate filaments. Filler materials formed as partially hollow cellulose acetate filaments have lower densities and higher filling values than conventional cellulose acetate filaments that are not hollow in design and are commonly used in cigarette filters. By providing such filler materials, the performance that can be achieved in mouthpieces and various applications can be greatly improved.

The term "hollow fiber" as used herein is to be understood in particular as a preferably cylindrical fiber having one or more continuous hollow spaces in its cross section. The hollow fibers are preferably at least partially crimped. However, the invention is not limited to crimped hollow fibers, but instead also relates to uncrimped fibers or their respective uses.

According to a variant of an embodiment of the invention, the hollow fibers are at least partially realized as multi-lumen hollow fibers. Compared to single-lumen hollow fibers, multi-lumen hollow fibers are very kink resistant and can achieve particularly high filtrona hardness without increasing the compression of the material.

The term "filtrona hardness" as used herein is to be understood as the filter hardness determined according to the filtrona principle. This principle involves determining the filter hardness by pressing the flat front end of a cylindrical rod with a diameter of 12 mm vertically onto a horizontally arranged filter rod with a load of 300 g. The ratio of the compressed diameter to the initial diameter predetermined at first contact yields the Filtrona hardness percentage.

According to a preferred embodiment of the invention, the cellulose acetate filaments in hollow form exhibit an at least partially trilobal, ie three-armed, star-shaped cross-sectional shape. Such a cross-sectional shape is suitable if the cellulose acetate filament has the largest possible specific surface area, allowing for example a high filtration capacity with an economical use of raw materials. Alternatively, it is possible to use bundles of very thin filaments of circular cross section to obtain the desired large specific surface area. However, other cross-sectional shapes of the hollow cellulose acetate filaments are also conceivable, such as, for example, a square cross-sectional shape.

The filter materials and/or filler materials of the present invention are economical to manufacture and can be processed alone or together with conventional non-hollow cellulose acetate filaments to have adequate suction resistance and optimal filtration properties. Can be made into a filter rod.

Since the filter material and/or filler material according to the invention comprises a filler material based on cellulose acetate filaments that are at least partially in the form of hollow cellulose acetate filaments, low suction resistance and low filtration performance can be achieved. This is because the filaments of filter material and/or filler material in the form of at least partially hollow cellulose acetate filaments have a small external surface area relative to the total fiber volume. Preferably, the filaments of filter material and/or filler material in the form of at least partially hollow cellulose acetate filaments exhibit as round a cross-section as possible.

In this connection, it was surprising to find that particularly high Filtrona hardnesses can be achieved in filter materials and/or filler materials by means of filaments in the form of at least partially hollow cellulose acetate filaments. . In fact, it has been found that filters formed at least in part from hollow cellulose acetate filaments (hollow fibers) achieve the desired minimum Filtrona hardness when the fiber weight per unit volume is low.

Because it is based on cellulose acetate filaments, the filter material and/or filler material of the present invention is suitable for producing filters with a uniform, white and flat mouth front end, and also achieves a selective phenol filtration effect. be able to.

From the point of view of the dialogue on smoking and health, the use of filter materials and/or filler materials based on cellulose acetate filaments initially suggests that filter rods, especially for cigarettes, have clearly superior properties for certain retention phenomena. manufacturing becomes possible. Therefore, filters made from cellulose acetate filter harmful nitrosamines and phenols much more efficiently than condensate and nicotine. Additionally, smokers rate the taste of today's common tobacco blends such as "American Blend," "German Blend," and "Virginia" as most pleasant when combined with cellulose acetate filter rods. . Another advantage of cellulose acetate filter rods, which must not be underestimated, can be found in the optical uniformity of the filter cross section.

The filter material and/or filler material of the present invention is formed at least in part from hollow cellulose acetate filaments serving as filler material, thereby providing a wide variety of draw resistances in filter rods made from the material of the present invention. and filtration performance can be achieved.

In particular, filter materials consisting at least partially of hollow cellulose acetate filaments have been shown to exhibit improved thermal cooling effects. It has been found that even with the use of hollow cellulose acetate filaments as filler material, it is still possible to achieve a very low filtration or retention effect on the suspended solids and gases to be removed. This effect is achieved by modifying the surface or the gas or air flow to be cleaned by hollow cellulose acetate filaments so as to retain a small amount of potentially suspended substances in the gas/air. Presumed. Another reason may be that the use of hollow cellulose acetate filaments makes it possible to achieve different particularly advantageous filter material surface structures.

The filter materials and/or filler materials of the present invention may further be used in heated particle-containing gases (particularly This has the advantage that it allows a particularly adjustable cooling of aerosols). Thus, by varying the proportion of hollow cellulose acetate filaments in the filter material and/or filler material, the desired cooling effect can be specifically tailored to the application.

It is noted that in the filter material and/or filler material of the invention, the flow is essentially around the hollow cellulose acetate filaments (=hollow fibers) and less through the hollow cellulose acetate filaments (=hollow fibers). This is even more important. From geometrical considerations it is clear that the distance between the fibers is considerably larger than the lumen (hollow part) of the hollow fiber. In that case, the viscosity of the aerosol (essentially air) will cause it to follow the path of least resistance (i.e., flow between the filaments rather than through the individual filaments).

In other words, the functional filtration surface is never maximized in the filter and/or filler materials of the present invention since there is no flow through the hollow cellulose acetate filaments in the filter and/or filler materials.

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

What is particularly noteworthy in this context is that hollow cellulose acetate filaments designed as hollow fibers do not have to be continuously hollow, but rather can be partially closed by kinks. Further, the shape may deviate from the ideal circular shape.

Embodiments of the present invention provide hollow cellulose acetate filaments of filter material and/or filler material that function on the one hand as support material and on the other hand as cooling material. By means of hollow cellulose acetate filaments which at the same time serve as supporting material, a particularly compact mouthpiece can be realized, in which case there is no need to increase the dimensions of the smoking product.

For example, it is conceivable for the filter material and/or the filler material to represent adjacent regions of hollow and non-hollow cellulose acetate filaments in the longitudinal direction of the mouthpiece. Mixtures of hollow and non-hollow cellulose acetate filaments are also conceivable. Alternatively, or in addition, hollow and non-hollow cellulose acetate filaments can be arranged in layers and then crimped. Doing so allows the maximum possible area of hollow cellulose acetate filaments to act as cooling material, thereby allowing better cooling of the particle-containing gas.

The filter material and/or filler material can be introduced into the smoking product, in particular in such a way that the hollow cellulose acetate filaments are arranged essentially longitudinally with respect to the direction of flow of the particle-containing gas or aerosol. By doing so, it is possible to achieve a filter material and/or filler material that reduces the pressure drop when the user draws on the mouthpiece, but does not make the user find the drawing action difficult or uncomfortable. can. By varying the alignment of the hollow cellulose acetate filaments relative to the direction of flow of the particle-containing gas or aerosol, the suction resistance of the filter material and/or filler material can be varied over a wide range and adapted to the respective application. .

By varying the proportion of hollow and non-hollow cellulose acetate filaments in the filter material and/or filler material and/or by varying the proportion of hollow and non-hollow cellulose acetate filaments in the filter material and/or filler material with respect to the direction of flow of the particle-containing gas or aerosol. By varying the arrangement of the hollow cellulose acetate filaments, it is possible not only to adjust the cooling and filtration performance, but also to adjust the suction resistance of the filter material and/or filler material.

Alternatively, it is provided that the filter material and/or filler material consists solely of hollow cellulose acetate filaments. In that case, the filter material and/or filler material is provided with optimal cooling efficiency with reduced filtration performance.

A further embodiment of the filter material and/or filler material of the invention provides the filter material and/or filler material being arranged as a separate segment in front of the mouthpiece in the direction of flow of the particle-containing gas or aerosol. The separate segments can be of various shapes. Although a cylindrical shape is cited as a preferred example, the present invention is not limited thereto. Conventional smoking products are typically of substantially cylindrical design. A separate segment can further be placed in front of any possible filter in the direction of flow of the particle-containing gas. The filter material and/or filler material, which acts as a cooling device and is formed as a separate segment, can, for example, consist entirely of hollow cellulose acetate filaments.

It is also conceivable that the separate segments include a wrapping made of, for example, paper or some kind of housing, so that the hollow cellulose acetate filaments serving as cooling material can be encapsulated. The wrapping or housing has inlet and outlet openings for the particle-containing gas/aerosol, respectively, through which the flow is passed by suction by the user's mouthpiece. Hollow cellulose acetate filaments serving as cooling material may optionally be added in or on the smoking product, for example in encapsulated form. In this way, the user has the option of only cooling the particle-containing gas if the user deems it necessary.

As already mentioned, the suction resistance of filter rods formed in particular from the filter material of the invention can be varied over a much wider range by varying the proportion of hollow cellulose acetate filaments in the filter material.

In summary, by using filter materials consisting at least partially of hollow cellulose acetate filaments, the suction resistance and filtration performance, respectively, can be adapted to a wide range of requirements, and are superior to conventional cellulose acetate filament-based filter materials. It can be said that this can be done more flexibly and clearly than with filter materials. Furthermore, the cooling effect can be variably adjusted.

In particular, the invention enables the mouthpiece or filter to be formed from cellulose acetate, which is normally present in the form of an essentially longitudinal strand of endless filaments, preferably consisting of individual filaments. The short sections of the strands are crimped so that they are irregularly arranged in non-parallel, converging and diverging directions compared to the primarily longitudinal direction of the strands.

In one possible embodiment of the filter material according to the invention, the surface structure of the filter material can be varied, in particular by using crimped cellulose acetate filaments. The crimp index of the cellulose acetate filaments is preferably between 10% and 60%, especially between 20% and 50%.

Crimp index Ix is a measure of crimp strength. The crimp index of filter tow is determined by tensile testing (force/strain relationship). It is defined as the ratio of the stretched length under test load _L2 minus the initial length under preload _L1 to the initial length under preload _L1 .

The test load is 25N and the preload is 2.5N. The clamp length is 250mm. The crimp index is determined in a tensile test at a constant strain rate of 300 mm/min on a G02 device from Borgwaldt GmbH, Hamburg. Ten individual measurements are recorded for each measurement. The test is carried out in a standard climate at 20° C. and 60% relative humidity.

The filter material of the invention is preferably in the form of a filter tow consisting of endless cellulose acetate filaments, especially cellulose-2,5-acetate filaments crimped in a stuffer box. To produce filter tow, a solution of approximately 30% cellulose-2,5-acetate in acetone is extruded through a specific spinneret, the acetone is evaporated by blowing heated air in the spinning chamber, and then a large number of Filaments (1,000-35,000) are collected to form a strip and crimped in a stuffer box. The product is then dried, filled into storage containers and finally pressed into bales of 300-600 kg.

Used to spin the spinning solution is a spinneret designed to spin hollow cellulose acetate filaments and/or cellulose acetate staple fibers.

After the filter tow bale is transported to the filter or cigarette manufacturer, the filter tow is removed from the bale and processed into filter rods on a filter rod machine as described, for example, in US 5,460,590A. In this case, the filter tow is drawn in a drawing device with additives that help bind the filaments and then, after the formation of three-dimensional rovings, is fed through an inlet funnel to a formatting device where it is It is compressed, wrapped in paper and cut to the final length of the filter rod.

The additive applied to bind the filaments can be, for example, a high boiling solvent of cellulose acetate, such as glycerin triacetate (triacetin), which temporarily solubilizes the surface of the filament after application. When two filaments come into contact, a permanent bond point occurs when, some time later, excess additive migrates to the fiber surface. This solidifies the solution, which was previously a droplet. Due to the aforementioned curing agent migration, mechanically strong three-dimensionally crosslinked filter rods are obtained after a storage period of less than 1 hour. Said filter rods are also called "spatial filters" and have a low packing density, usually from 20 mg/ml to 90 mg/ml, preferably from 30 mg/ml to 70 mg/ml, more preferably from 40 mg/ml to 60 mg/ml. Due to their hardness, these filter rods can be processed without problems at high speeds in modern cigarette machines.

Tests have shown that using hollow cellulose acetate filaments in the filter material can reduce the filtration performance of spatial filters and increase cooling efficiency while maintaining specifications such as length, diameter, suction resistance, and filament titer. Shown.

In this way, by increasing the proportion of hollow fibers (hollow cellulose acetate filaments) in the filter material, the suction resistance can be reduced to the required level without increasing the filament titer, despite improving cooling efficiency and decreasing filtration performance. can be kept within range.

Therefore, according to the realization of the filter material of the invention, the percentage of hollow-shaped (hollow) cellulose acetate filaments in the filter material is between 20 and 100%, preferably between 40 and 100%, more preferably depending on the application: Particularly defined as 70-100%.

In particular, the hollow portion in the filter material is preferably between 25 and 90%, preferably between 50 and 80%. This hollow part makes a decisive contribution to the filtration performance on the one hand and to the reduction of the suction resistance on the other hand. This is only possible with a suitable proportion of hollow fibers in the filter material and cannot be achieved with closed filaments. In this case, the hollow portion corresponds to the ratio of the "hollow" area of the filter material to the "total" cross-sectional area of the fibers.

It is noteworthy in this context that the filter material of the present invention also provides a method in which the filament diameter of the cellulose acetate filaments is significantly greater than that of other (synthetic) hollow fibers with filament diameters in the range 10-30 μm. It is characterized by being large. In contrast, the filament diameter of hollow cellulose acetate filaments ranges from 30 to 150 μm (external diameter), preferably from 50 to 120 μm (external diameter), more preferably from 60 to 100 μm (external diameter). In this way, the hollow area can be increased and thus the specific filtration performance of the filter material and/or filler material of the invention is significantly reduced, while at the same time the cooling efficiency of the filter material and/or filler material of the invention is It has increased.

The invention further relates to cigarette filters made from filter materials of the type described above.

According to a non-limiting embodiment, filters according to the invention can be manufactured using thermoplastic cellulose ester fiber materials or, in the case of non-thermoplastic cellulose esters, water-soluble adhesives. . In the first case of thermoplastic cellulose ester fiber materials, two cases can be distinguished. In the first case, the fiber material is manufactured from natural thermoplastic cellulose esters, such as cellulose acetate butyrate, for example. No further measures are required here for processing the filter tow into the filter of the invention. For example, with non-thermoplastic base polymers such as cellulose-2,5-acetate, it is necessary to add a suitable plasticizer to thermoplasticize the polymer.

To produce the filters of the invention, the filter tow is drawn from the bale, pneumatically spread, and stretched according to methods customary for spatial filters.

Within the context of the teachings of the present invention, the weight of acetate can be up to 5 mg, at least about 2 mg, especially about 3-4 mg per mm of filter length. Above a maximum value of 5 mg per mm of filter length, such products are not economical enough. Preferably, a minimum value of about 2 mg per mm of filter length is maintained. According to the prior art, below this value it is no longer possible to maintain the desired minimum 88% cigarette filter hardness.

Within the context of the teachings of the present invention, the suction resistance may be up to 2 mm daPa per mm of filter length, at least about 0.1 daPa, in particular between 0.2 daPa and 1 daPa. A suction resistance of 0.3 daPa to 0.7 daPa per mm of filter length is particularly preferred. It is preferred to maintain a minimum value of 0.3 daPa per mm of filter length. According to the prior art, below this value it is no longer possible to maintain the desired minimum 88% cigarette filter hardness.

Some essential aspects of the invention are summarized below.

According to a first aspect, the invention relates to filter and/or filler materials for mouthpieces for use in smoking or HNB products. Here, the filter material and/or filler material is a cellulose acetate-based filament that is at least partially formed as a hollow and/or tubular cellulose acetate filament.

According to a variant of one embodiment of the filter material and/or the filler material, the cellulose acetate filaments are hollow, in particular crimped, endless cellulose acetate filaments and/or hollow, in particular crimped, truncated endless cellulose acetate filaments. Contains filament.

According to one embodiment variant of the filter material and/or filler material, the crimp index of the cellulose acetate filaments is between 10% and 60%, in particular between 20% and 50%.

According to a variant of one embodiment of the filter material and/or filler material, the cellulose acetate filaments are formed from a thermoplastic cellulose material, and when the cellulose acetate filaments contain a plasticizer, the cellulose acetate filaments have a homogeneously dispersed plasticizer. and/or a water-soluble adhesive is present on the surface of the cellulose acetate filament.

According to one embodiment variant of the filter material and/or filler material, if a plasticizer is used, the plasticizer content is between 1% and 40%.

According to a variant of one embodiment of the filter material and/or filler material, if a plasticizer is used, the plasticizer is triacetin, triethylene glycol diacetate and/or citric acid diethyl ester.

According to a variant of one embodiment of the filter material and/or filler material, the cellulose acetate filaments have a fineness of 5 to 30 denier, preferably 10 to 25 denier, more preferably 15 to 20 denier.

According to a variant of one embodiment of the filter material and/or filler material, the total titer of the filter material and/or filler material is between 4,000 and 40,000 denier, preferably between 6,000 and 30,000 denier. be.

According to a variant of one embodiment of the filter material and/or filler material, the hollow portions of the filter material and/or filler material are 25% to It ranges from 90%, preferably from 50% to 80%.

According to a variant of one embodiment of the filter material and/or filler material, the filament diameter of the cellulose acetate filaments is from 30 to 150 μm (external diameter), preferably from 50 to 120 μm (external diameter), more preferably from 60 to 100 μm (outer diameter).

According to a variant of one embodiment of the filter material and/or filler material, the mass fraction of hollow cellulose acetate filaments is between 20 and 100%, preferably between 50 and 100%, more preferably between 70 and 100%.

According to a variant of one embodiment of the filter material and/or filler material, the hollow cellulose acetate filaments are spaced apart from each other in an irregular arrangement, the cellulose acetate filaments are cross-linked, and the connected cellulose acetate filaments are , intertwined and/or intertwined.

According to a variant of one embodiment of the filter material and/or filler material, a binder, in particular an organic or inorganic binder, is further provided for binding the cellulose acetate filaments.

According to a further aspect, the invention relates to a mouthpiece for use with smoking or HNB products. The mouthpiece here comprises a filter material and/or filler material of the type of the invention described above.

According to a further aspect, the invention relates to a cigarette filter or a cigarette filter element having a filter material and/or filler material of the type of the invention as described above.

According to a variant of the respective embodiment of the cigarette filter or cigarette filter element, at least one of the following features is realized.
- The fiber density of the filter material and/or filler material is 10-70 kg/m ³ , preferably 20-70 kg/m ³ , more preferably 40-60 kg/m ³ .
- The cigarette filter or cigarette filter element has a Filtrona hardness of at least 88%, preferably from 88% to 95%, more preferably from 90% to 93%.
- The cigarette filter or cigarette filter element has a suction resistance of at least 0.1 daPa per mm of filter length, preferably from 0.2 daPa to 1.0 daPa, more preferably from 0.3 daPa to 0.7 daPa.
- The filter material and/or filler material contains a plasticizer, and the plasticizer content is between 1% and 40%.

According to a variant of the embodiment of the cigarette filter/cigarette filter element, in particular capsule-shaped or capsule-like flavor release elements are further incorporated into the filter material and/or the filler material.

According to a variant of the embodiment of the cigarette filter/cigarette filter element, in addition to the hollow cellulose acetate filaments, the cigarette filter or cigarette filter element each further comprises solid cellulose acetate filaments.

According to a further aspect, the invention relates to the use of the filter and/or filler materials of the invention in smoking products or HNB products.

According to a further aspect, the invention relates to a method for manufacturing filter and/or filler materials for mouthpieces for use in smoking or HNB products. wherein the filter material and/or the filler material preferably consists of cellulose acetate filaments and/or cellulose acetate staple fibers, and an acetone solution of cellulose acetate with an acetyl value of at least 53% is spun into a fiber having a plurality of openings. The cellulose acetate filament is extruded through a die and subsequently cut into cellulose acetate staple fibers as required, and a number of cellulose acetate filaments and/or cellulose acetate staple fibers so obtained are optionally collected. to form a potentially crimped filter tow,
The spinneret through which the solution of cellulose acetate is extruded is designed so that hollow cellulose acetate filaments are spun.
The present disclosure includes the following embodiments.
<1> Filter material and/or filler material for mouthpieces for use in smoking or HNB products based on cellulose acetate filaments, at least in part formed as hollow and/or tubular cellulose acetate filaments.
<2> The filter material according to <1> above, wherein the cellulose acetate filament comprises a hollow, particularly crimped, endless cellulose acetate filament and/or a hollow, particularly crimped, cut endless cellulose acetate filament; /or filler material.
<3> The filter material and/or filler material according to <1> or <2> above, wherein the cellulose acetate filament has a crimp index of 10% to 60%, particularly 20% to 50%.
<4> The cellulose acetate filament is formed from a thermoplastic cellulose material, and when the cellulose acetate filament includes a plasticizer, the cellulose acetate filament includes a uniformly distributed plasticizer, and/or
a water-soluble adhesive is present on the surface of the cellulose acetate filament;
The filter material and/or filler material according to any one of <1> to <3> above.
<5> When a plasticizer is used, the filter material and/or filler material according to any one of <1> to <4>, wherein the plasticizer content is 1% to 40%.
<6> When a plasticizer is used, the filter material according to any one of <1> to <5> above, wherein the plasticizer is triacetin, triethylene glycol diacetate and/or citric acid diethyl ester; /or filler material.
<7> The filter according to any one of <1> to <6>, wherein the cellulose acetate filament has a fineness of 5 to 30 denier, preferably 10 to 25 denier, more preferably 15 to 20 denier. Materials and/or Filler Materials.
<8> Any one of <1> to <7> above, wherein the total titer of the filter material and/or filler material is 4,000 to 40,000 deniers, preferably 6,000 to 30,000 deniers. Filter materials and/or filler materials as described in section.
<9> The hollow portion of the filter material and/or filler material ranges from 25% to 90%, preferably from 50% to 80%, with respect to a cross section perpendicular to the fibers of the filter material and/or filler material. The filter material and/or filler material according to any one of <1> to <8> above.
<10> The above <1>, wherein the filament diameter of the cellulose acetate filament is within the range of 30 to 150 μm (outer diameter), preferably 50 to 120 μm (outer diameter), more preferably 60 to 100 μm (outer diameter). The filter material and/or filler material according to any one of ~<9>.
<11> The hollow cellulose acetate filament has a mass fraction of 20 to 100%, preferably 50 to 100%, more preferably 70 to 100%, according to any one of <1> to <10> above. filter material and/or filler material.
<12> Hollow cellulose acetate filaments are spaced apart from each other in an irregular arrangement, making the cellulose
The filter material and/or the filter material according to any one of <1> to <11>, wherein the cellulose acetate filaments are crosslinked and the connected cellulose acetate filaments are entangled and/or entangled with each other. or filler material.
<13> The filter material and/or according to any one of <1> to <12>, wherein a binder, in particular an organic or inorganic binder, is further provided for binding the cellulose acetate filaments. filler material.
<14> A mouthpiece for use in a smoking product or HNB product, comprising the filter material and/or filler material according to any one of <1> to <13> above.
<15> The filter material and/or filler material has a fiber density of 10 to 70 kg/m ³ , preferably 20 to 70 kg/m ³ , more preferably 40 to 60 kg/m ³ , and/or
the cigarette filter or cigarette filter element has a filtrona hardness of at least 88%, preferably from 88% to 95%, more preferably from 90% to 93%, and/or
the cigarette filter or cigarette filter element has a suction resistance of at least 0.1 daPa per mm of filter length, preferably from 0.2 daPa to 1.0 daPa, more preferably from 0.3 daPa to 0.7 daPa, and/or
The filter material and/or filler material contains a plasticizer, and the plasticizer content is 1% to 40%.
The mouthpiece according to <14> above.
<16> Mouthpiece according to <14> or <15>, wherein a particularly capsule-like or capsule-like flavor release element is further incorporated into the filter material and/or filler material.
<17> The mouthpiece according to any one of <14> to <16>, wherein the filter material and/or filler material further includes solid cellulose acetate filaments in addition to hollow cellulose acetate filaments.
<18> A cigarette filter or cigarette filter element comprising the filter material and/or filler material according to any one of <1> to <13>.
<19> The filter material and/or filler material has a fiber density of 10 to 70 kg/m ³ , preferably 20 to 70 kg/m ³ , more preferably 40 to 60 kg/m ³ , and/or
said cigarette filter or cigarette filter element has a filtrona hardness of at least 88%, preferably from 88% to 95%, more preferably from 90% to 93%, and/or
said cigarette filter or cigarette filter element has a suction resistance of at least 0.1 daPa per mm of filter length, preferably from 0.2 daPa to 1.0 daPa, more preferably from 0.3 daPa to 0.7 daPa, and/or
The filter material and/or filler material contains a plasticizer, and the plasticizer content is 1% to 40%.
The cigarette filter or cigarette filter element according to <18> above.
<20> The cigarette according to <18> or <19>, wherein a capsule-like or capsule-like flavor release element is further incorporated into the filter material and/or filler material.
filter or cigarette filter element.
<21> The cigarette filter or the cigarette filter according to any one of <18> to <20>, wherein the cigarette filter or cigarette filter element each further includes a solid cellulose acetate filament in addition to a hollow cellulose acetate filament. Cigarette filter element.
<22> Use of the filter material and/or filler material according to any one of <1> to <13> above in a smoking product or an HNB product.
<23> An acetone solution of cellulose acetate having an acetyl value of at least 53% is extruded through a spinneret having a plurality of orifices, and then the cellulose acetate filaments are optionally cut into cellulose acetate staple fibers and the A large number of cellulose acetate filaments and/or cellulose acetate staple fibers thus obtained are optionally assembled to form a potentially crimped filter tow;
the spinneret through which the solution of cellulose acetate is extruded is designed such that hollow cellulose acetate filaments are spun;
Filter materials and/or filler materials for mouthpieces for use in smoking products or HNB products, in particular any one of <1> to <13> above, consisting of cellulose acetate filaments and/or cellulose acetate staple fibers. Methods for manufacturing the described filter materials and/or filler materials.

Claims (18)

An acetone solution of cellulose acetate having an acetyl value of at least 53% is extruded through a spinneret having a plurality of openings, and subsequently the cellulose acetate filaments are cut into cellulose acetate staple fibers, thus obtained. a plurality of cellulose acetate filaments and/or cellulose acetate staple fibers are assembled to form a crimped filter tow;
the spinneret through which the solution of cellulose acetate is extruded is designed such that hollow cellulose acetate filaments are spun;
A method for producing filter and/or filler materials consisting of cellulose acetate filaments and/or cellulose acetate staple fibers for mouthpieces for use in smoking or HNB products, comprising:
With respect to the cross section perpendicular to the fibers of the filter material and/or filler material, the hollow portion of the filter material and/or filler material ranges from 25% to 90%, preferably from 50% to 80%;
The filament diameter of the cellulose acetate filament is within the range of 60 to 100 μm.
Method. Process according to claim 1, wherein the crimp index of the cellulose acetate filaments is between 10% and 60%, in particular between 20% and 50%. the cellulose acetate filament comprises a uniformly distributed plasticizer, and/or
a water-soluble adhesive is present on the surface of the cellulose acetate filament;
The method according to claim 1 or 2. A method according to any one of claims 1 to 3, wherein the cellulose acetate filaments and/or cellulose acetate staple fibers contain a plasticizer. According to any one of claims 1 to 4, the cellulose acetate filament and/or cellulose acetate staple fiber comprises a plasticizer, and the plasticizer is triacetin, triethylene glycol diacetate and/or citric acid diethyl ester. the method of. A method according to any one of claims 1 to 5, wherein the cellulose acetate filaments have a fineness of 5 to 30 denier, preferably 10 to 25 denier, more preferably 15 to 20 denier. A method according to any one of claims 1 to 6, wherein the total titer of the filter material and/or filler material is between 4,000 and 40,000 denier, preferably between 6,000 and 30,000 denier. Any one of claims 1 to 7, wherein the mass fraction of hollow cellulose acetate filaments in the filter material and/or filler material is between 20 and 100%, preferably between 50 and 100%, more preferably between 70 and 100%. The method described in section. Claims 1 to 8, wherein the hollow cellulose acetate filaments are separated from each other in an irregular arrangement, the cellulose acetate filaments are crosslinked, and the connected cellulose acetate filaments are intertwined and/or entangled with each other. The method described in any one of the above. A method according to any one of claims 1 to 9, wherein a binder, in particular an organic or inorganic binder, is further provided for binding the cellulose acetate filaments. A mouthpiece for use in a smoking or HNB product comprising a filter material and/or filler material based on cellulose acetate filaments, at least in part formed as hollow and/or tubular cellulose acetate filaments, comprising :
With respect to the cross section perpendicular to the fibers of the filter material and/or filler material, the hollow portion of the filter material and/or filler material ranges from 25% to 90%, preferably from 50% to 80%;
The filament diameter of the cellulose acetate filament is within the range of 60 to 100 μm.
mouthpiece . The filter material and/or filler material has a fiber density of 10 to 70 kg/m ³ , preferably 20 to 70 kg/m ³ , more preferably 40 to 60 kg/m ³ , and/or
said mouthpiece comprises a cigarette filter or cigarette filter element, said cigarette filter or cigarette filter element having a filtrona hardness of at least 88%, preferably from 88% to 95%, more preferably from 90% to 93%; and /or,
The mouthpiece comprises a cigarette filter or a cigarette filter element, the cigarette filter or cigarette filter element having a pressure per mm of filter length of at least 0.1 daPa, preferably from 0.2 daPa to 1.0 daPa, more preferably from 0.3 daPa to 0.3 daPa. having a suction resistance of 0.7 daPa,
The mouthpiece according to claim 11. Mouthpiece according to claim 11 or 12, wherein a capsule -like or capsule-like flavor releasing element is further incorporated into the filter material and/or filler material. Mouthpiece according to any one of claims 11 to 13, wherein the filter material and/or filler material further comprises solid cellulose acetate filaments in addition to hollow cellulose acetate filaments. A cigarette filter or cigarette filter element comprising a filter material and/or filler material based on cellulose acetate filaments, at least in part formed as hollow and/ or tubular cellulose acetate filaments , comprising:
With respect to the cross section perpendicular to the fibers of the filter material and/or filler material, the hollow portion of the filter material and/or filler material ranges from 25% to 90%, preferably from 50% to 80%;
The filament diameter of the cellulose acetate filament is within the range of 60 to 100 μm.
Cigarette filter or cigarette filter element . The filter material and/or filler material has a fiber density of 10 to 70 kg/m ³ , preferably 20 to 70 kg/m ³ , more preferably 40 to 60 kg/m ³ , and/or
said cigarette filter or cigarette filter element has a filtrona hardness of at least 88%, preferably from 88% to 95%, more preferably from 90% to 93%, and/or
the cigarette filter or cigarette filter element has a suction resistance of at least 0.1 daPa per mm of filter length, preferably from 0.2 daPa to 1.0 daPa, more preferably from 0.3 daPa to 0.7 daPa;
A cigarette filter or cigarette filter element according to claim 15. Cigarette filter or cigarette filter element according to claim 15 or 16, wherein a capsule-like or capsule-like flavor release element is further incorporated into the filter material and/or filler material. Cigarette filter or cigarette filter element according to any one of claims 15 to 17, wherein the cigarette filter or cigarette filter element each further comprises, in addition to hollow cellulose acetate filaments, solid cellulose acetate filaments.