DE102019135114A1 - FILTER AND / OR FILLING MATERIAL FOR MOUTHPIECES FOR USE WITH SMOKED PRODUCTS OR HNB PRODUCTS, MOUTHPIECES AND CIGARETTE FILTERS WITH SUCH FILTER AND / OR FILLING MATERIAL, AS WELL AS PROCESS FOR PRODUCING SUCH FILTER AND / OR FILTER - Google Patents

Abstract

The invention relates to a filter and / or filler material for mouthpieces for use with tobacco products or HNB products, the filter and / or filler material being based on cellulose acetate filaments which are at least partially designed as hollow cellulose acetate filaments. The invention also relates to a mouthpiece for use with tobacco products or HNB products, the mouthpiece having a filter and / or filler material of the type according to the invention. The invention also relates to a cigarette filter with such a filter and / or filler material and a corresponding method for producing a filter and / or filler material for mouthpieces for use with tobacco products or HNB products.

Description

The present invention relates to a filter and / or filling material for mouthpieces for use with smoking products or HNB products and the use of such a filter and / or filling material in mouthpieces for smoking products or in cigarette filters or in mouthpieces for HNB products. According to a further aspect, the invention relates to a method for producing such a filter and / or filler material.

Tobacco products within the meaning of the present invention relate to classic tobacco products, in particular cigarettes, but also pipes and marijuana products as well as so-called heat-not-burn (HNB) products, vaping products and so-called hybrid products.

Depending on the application, mouthpieces for the use of smoking products have different functions. On the one hand, mouthpieces can serve as a filter device in order, for example, to extract harmful components, such as condensed substances such as tar, and particulate matter entrained by the smoke flow, from a tobacco smoke flow. This filter function is used in particular in classic tobacco applications. A corresponding mouthpiece can be designed as an integral part of a cigarette or a cigarillo and thus form a “tip” on the cigarette or on the cigarillo.

Another type of mouthpiece is replaceable devices, such as replaceable filter elements that can be removed after use. Such mouthpieces are received in corresponding holders, for example in a cigarette holder or in a pipe mouthpiece.

A mouthpiece designed as an integral part of a cigarette is the cigarette filter. The cigarette filter is intended to prevent the proportion of harmful substances such as condensate and gases in the smoke of the cigarette. In addition, the smoke is perceived as somewhat milder or more pleasant by a large proportion of smokers through the filter. In the case of a classic filter cigarette, the filter is wrapped in a filter wrapping paper and is coupled to the tobacco rod with what is known as tipping paper, with most industrially manufactured cigarettes being provided with a filter. Do-it-yourselfers can buy these in tobacco shops.

Numerous types of filter materials have already been used, particularly in order to reduce the content of the constituents of tobacco smoke before it reaches the smoker's respiratory system. In addition to removing the harmful constituents in large quantities, a satisfactory filter must also be effective without undesirably hindering the passage of air or smoke through the filter, so that too strong a draft is required. When used in tobacco smoke filters, however, the filter material must not change the taste of the tobacco smoke by adding its own taste.

Another essential factor in the production of a satisfactory tobacco smoke filter is that its production is not too expensive so that the final price of the smoking article in which the filter is used does not rise too high.

The present invention, however, relates less to filter materials for the classic tobacco applications described above, but in particular to filter and / or filling materials for mouthpieces for the use of tobacco products, these filter and / or filling materials in particular having other functions than just a filter function.

In other applications, a filter function of the mouthpieces is by no means in the foreground. This applies, for example, to heat-not-burn products ("HNB products"), which have enjoyed increasing popularity in recent years. In these devices, a portion of processed tobacco is heated by a heat source during use, but not burned. In the process, volatile tobacco components such as flavorings, nicotine, glycerine and water evaporate and are carried away by the air drawn through the HNB product by the user. While the released substances cool down, an aerosol is formed which is inhaled by the user.

Commercially available HNB products usually include a device consisting of a power supply that supplies a heating element and a separate consumable consisting of a portion of processed tobacco, a support element such as a tubular cellulose acetate segment, a so-called cooling element downstream in the flow direction, for example in the form of a crimped polylactide film, which is gathered into a cylinder with many axial channels, as well as a mouth-side filter. The consumables are placed in the device before use in such a way that the heating element heats the portion of tobacco when the HNB product is used.

For example, in a so-called IQOS / HEETS product from Philip Morris, the tobacco portion is impaled on a heating sheet in the device. An IQOS / HEETS product is an IQOS device marketed by Philip Morris with the associated HEETS consumable. The HEETS consumable is a heat-not-burn product in which tobacco is simply heated instead of being burned.

A competitor product from BAT ("Glo") heats the tobacco from the outside, whereby the so-called cooling element is replaced by a tube. In these devices, too, a portion of processed tobacco is heated by a heat source during use, but not burned. In the process, volatile tobacco components such as flavorings, nicotine, glycerine and water evaporate and are carried away by the air drawn through the HNB product by the user. While the released substances cool down, an aerosol is formed which is inhaled by the user.

The consumables known for this application have the disadvantage that their mouth-side filters can heat up considerably due to their proximity to the heating element and due to the hot steam generated when the HNB product is used.

In the case of so-called hybrid products, an aerosol former is first evaporated (propylene glycol, glycerine), then an aerosol is created by cooling. This aerosol is passed through a serving of processed tobacco and inhaled by the consumer. In such applications, too, the mouthpiece has the particular function of protecting the user-side end against heating that is unpleasant for the user.

In contrast to conventional tobacco products, in which tobacco is burned, it may be desirable in the case of consumables of HNB products that the elements downstream of the heated tobacco portion in the flow direction, such as cooling element and mouth-side filter, only have a low filtering effect with regard to condensed components such as tar as these smoke components can be produced in significantly smaller quantities.

• • Zugwiderstand
• • Filtrationsleistung
• • Filterstabhärte/Filtronahärte
• • Optik
• • Wirtschaftlichkeit der Herstellung
• • Rauchtemperatur

The materials required to form a mouthpiece for tobacco products must therefore be adapted and in particular adaptable to the physical properties of the smoke (temperature, flow profile, etc.) and to the chemical composition. In particular, with conventional cigarette filters as well as with HNB products, there are a number of target parameters that must be set or fulfilled by a suitable choice and configuration of the mouthpiece materials. In particular, these are the following target parameters, which are briefly discussed below:

• • Draw resistance
• • Filtration performance
• • Filter rod hardness / Filtrona hardness
• • Optics
• • Economy of production
• • Smoking temperature

The hardness of the filter rod is an important target criterion for cigarette filters. It is usually given as the so-called Filtrona hardness. The Filtrona hardness is determined by pressing a cylindrical rod 12 mm in diameter with its flat end face vertically with a load of 300 g onto a horizontally positioned filter rod. The ratio of the compressed diameter to the initial diameter previously determined by the first contact gives the percentage of the Filtrona hardness.

It should be emphasized that the Filtrona hardness is only measured on a filter, but not on the underlying filter (raw) material. In particular, the triacetin sprayed on all cigarette filters affects the Filtrona hardness.

The minimum limit for Filtrona hardness is around 88% and is based on market requirements. 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, for a given filter diameter, the Filtrona hardness is essentially determined by the fiber weight per unit volume. In particular, the filament titer has only a minor influence on the Filtrona hardness.

Occasionally, a higher Filtrona hardness is achieved with a thicker filter wrap paper or a thicker tipping paper. A tipping paper is a paper with which either several filter elements are coupled to one another or filter elements are coupled to the tobacco rod. However, increasing the Filtrona hardness by using a thicker filter wrap paper or tipping paper has economic disadvantages as this approach is expected to be more expensive.

The so-called “hot collapse”, in which the filter hardness decreases during smoking, is related to the Filtrona hardness. This can occur in particular if, in the case of a classic cigarette, the filter heats up in the presence of moisture during one of the last puffs. This undesirable effect can also occur with HNB products.

In addition to a Filtrona hardness that is as constant and high as possible when a smoking product is used, the mouthpiece material should also exhibit a filtration performance that has been determined or can be determined in advance. The filtration performance with regard to condensed matter (droplets, particles), also known as condensate or tar, is of interest for conventional tobacco products and HNB products, since a large number of substances with negative health relevance can be found in the condensed matter.

In the case of conventional products (in addition to other influencing factors such as tobacco blend, ventilation, etc.), the filtration capacity is selected in order to adjust the "delivery" of the cigarette (content of smoke ingredients in the mainstream smoke). In many markets, the upper limit of delivery is imposed by statutory provisions. Below the legal limit, the “delivery” can be adapted to the preferences of the consumers.

With HNB products, there is much less condensed matter with negative health relevance in the aerosol than with conventional products. However, since more desirable substances, such as taste-forming substances and nicotine, are also present in the condensate, the aim here is rather to select the lowest possible filtration performance, which, however, must not drop to zero.

With regard to the target parameter “draw resistance” it should be noted that consumers prefer a certain draw resistance range when consuming a tobacco product. In the case of conventional cigarettes, the filter (in addition to setting the "Delivery") is used to set the draw resistance of the cigarette.

In the case of HNB products, however, the draw resistance contribution of the mouth-side filter (mouthpiece) should be as low as possible, since the other components of the HBN device, in particular the heated tobacco portion and the device, already have a high draw resistance contribution. A low draw resistance of the filter (mouthpiece) leads to degrees of freedom in the other components of the HBN device, which is desirable.

However, the draw resistance and the filtration performance are closely linked. Both can be reduced in several ways, but this often negatively affects other parameters.

For example, the draw resistance and the filtration performance can be reduced by reducing the filter length. But as soon as the filter length becomes smaller than the filter diameter, the processability becomes problematic. A shorter filter also leads to a shorter cooling section, which is problematic for the heat balance.

Alternatively or in addition to this, the draw resistance and the filtration performance can be reduced by reducing the fiber weight in the filter material per volume fraction and / or the total denier. However, this has the disadvantage that the Filtrona hardness decreases and under certain circumstances the minimum hardness can no longer be achieved.

As an alternative or in addition to this, the draw resistance and the filtration performance can be reduced by increasing the filament denier. With a constant filter diameter and a given fiber weight per unit volume, the filtration performance and the draw resistance are reduced as the filament titre increases, which is desirable for HNB products compared to conventional products. Since, as stated above, the Filtrona hardness hardly depends on the filament titer, the hardness is not negatively influenced either.

With regard to the target parameter “optics” it should be noted that the consumer prefers a mouthpiece with a flat, white cross-sectional area on the mouth side. However, there are also products that are shaped into a tube on the mouth side.

With regard to the smoking temperature, it should be noted that the smoking temperature is not a problem with conventional products today. With commercially available HNB products, however, the smoking temperature is noticeably high and uncomfortably high for some consumers. In addition, commercially available HNB products require cooling to cool down the evaporated components so that an aerosol is first created from the gaseous components.

In the case of commercially available HNB products, the distance from the heating element to the end of the mouth of the HNB article is certainly the most important parameter for cooling the aerosol. For example, it is known to connect a so-called cooling element downstream of the tobacco portion and the support element. The cooling element can be designed in the form of a crimped polylactide film or in the form of a cardboard tube, with - in addition to cooling - this element following the tobacco portion and the support element also has the function of a placeholder, which gives mechanical stability.

Ultimately, mouthpiece materials must meet the target parameter cost-effectiveness. In particular, there is a need for suitable mouthpiece materials that can be produced with the least possible amount of material and with the lowest possible process costs.

Although conventional cigarette filters, which are usually made up of cellulose acetate filaments, ensure optimal filtration of smoke constituents, these filter materials can often only be used to a limited extent in other applications, in particular for HNB products or e-cigarettes, since in these applications the filter materials or materials for the Mouthpiece have to take on other functions.

HNB products, as well as conventional smoking articles, generally have the disadvantage that the inhaled aerosol is absorbed by the user at a high temperature. This is sometimes uncomfortable for the user. Especially in the case of HNB products, the task of the mouthpiece materials is to cool the aerosol with the lowest possible filtration performance.

But even with classic cigarettes, in particular with so-called slim or ultra-slim cigarettes, ie cigarettes with a small diameter of, for example, 5.0 mm to 6.5 mm, filter materials or materials for the mouthpiece have to be compared to filter materials for King-size cigarettes - offer reduced filtration performance and increased cooling and improved haptic properties (firm, but not too hard grip). Naturally, there is less smoke / taste when burned than with a king-size cigarette. In order not to further reduce the taste, a low filtration rate is aimed for. If only the amount of filter material is reduced for this purpose, the filter hardness will eventually become insufficient.

Filters for slim or ultra-slim cigarettes also have significantly higher draw resistance than king-size filters with the same fiber density, which is generally not desired.

For both HNB products and ultra-slim cigarettes, it was proposed to achieve the desired reduced filtration performance with regard to condensable components such as tar, as well as sufficient filter hardness by increasing the film titer while maintaining the total titer. However, this approach has the disadvantage that such fiber materials with a high filament denier have economic disadvantages on the conventionally used spinning machines. In the production of conventional filter tow, a solution of approx. 30% cellulose-2,5-acetate in acetone is pressed through spinnerets, the acetone evaporates in a spinning shaft by blowing heated air, a large number of filaments (1,000 to 35,000) combined into a ribbon and then curled in a shrub chamber. In the case of higher filament titers, a larger amount of the solvent has to be evaporated per filament, which, due to the larger ratio of filament cross-sectional area to filament surface, takes more time and results in slower spinning speeds.

On the basis of this problem, the present invention is based on the object of specifying a material which is suitable for a wide range of applications in smoking products.

In particular, the present invention is based on the object of specifying a filter material with low draw resistance and low filtration performance, with the filter material being able to achieve a sufficiently high Filtrona hardness that is as constant as possible when used in smoking goods, and the filter material can nevertheless be produced particularly economically.

In addition, the filter material should be suitable for producing a filter with a uniform, white and flat face on the mouth side.

In this context, it is also desirable that the filter material shows a selective filtration effect on phenols.

The filter material should in particular be suitable for reliably cooling a heated, particle-laden gas so that the temperature of the gas, aerosol or vapor absorbed by a smoking article can be reduced.

Furthermore, the material should be suitable so that when the material is used as a filter material for slim or ultra-slim cigarettes, in particular, an adjustable and, in particular, reduced draw resistance compared to king-size filters can be achieved.

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

Accordingly, the invention relates in particular to a material for forming a mouthpiece for tobacco products, the material having a filler material based on cellulose acetate filaments which are at least partially designed as hollow cellulose acetate filaments. The filler material, which is partially designed as hollow cellulose acetate filaments, has a lower density and a higher fill value than classic cellulose acetate filaments, which are not hollow-shaped and which are usually used in cigarette filters. By providing such a filler material, the performance that can be achieved with the mouthpiece and the range of applications can be significantly increased.

The term “hollow fiber” used here is to be understood in particular as a preferably cylindrical fiber which has one or more continuous cavities in cross section. The hollow fibers are preferably at least partially curled. However, the invention is not limited to crimped hollow fibers, but also relates to non-crimped fibers or their use.

According to variant embodiments of the present invention, the hollow fibers are at least partially designed as multi-lumen hollow fibers. Compared to single-lumen hollow fibers, multi-lumen hollow fibers are significantly more kink-resistant, which means that particularly high Filtron hardnesses can be achieved without increased material compression.

The term “Filtrona hardness” used here is to be understood as the filter hardness determined according to the Filtrona principle. With this principle, the filter hardness is determined by pressing a cylindrical rod 12 mm in diameter with its flat face vertically with a load of 300 g onto a horizontally positioned filter rod. The ratio of the compressed diameter to the initial diameter previously determined by the first contact gives the percentage of the Filtrona hardness.

According to preferred embodiments of the present invention, the hollow-shaped cellulose acetate filaments have at least partially a trilobal, i.e. three-armed star-shaped cross-sectional shape. Such a cross-sectional shape is advisable when the cellulose acetate filaments are to have the largest possible specific surface area, for example in order to enable a high filtration capacity with the economical use of raw materials at the same time. Alternatively, it is possible to obtain the desired large specific surface area by means of a bundle of extremely fine filaments with a circular cross-section. However, other cross-sectional shapes are also conceivable for the hollow cellulose acetate filaments, such as, for example, a square cross-sectional shape.

The filter and / or filler material of the present invention is inexpensive to manufacture and can be processed alone or with classic cellulose acetate filaments that are not hollow-shaped to form a filter rod with suitable tensile resistance and optimized filter properties.

Because the filter and / or filler material according to the invention has a filler material which is based on cellulose acetate filaments, which are at least partially designed as hollow cellulose acetate filaments, a low tensile resistance and a low filtration performance can be achieved, since the at least partially designed as hollow cellulose acetate filaments of the Filter and / or filler material have a small outer surface based on the total fiber volume. It is preferred here that the filaments of the filter and / or filler material, which are at least partially designed as hollow cellulose acetate filaments, have a cross-section that is as round as possible.

In this context, it was surprisingly found that because of the filaments, which are at least partially designed as hollow cellulose acetate filaments, with the filter and / or filler material, particularly high Filtron hardnesses can be achieved. In fact, it has been found that filters which are at least partially formed from hollow cellulose acetate filaments (hollow fibers) achieve the desired minimum Filtrona hardness with a lower fiber weight per unit volume.

Since it is based on cellulose acetate filaments, the filter and / or filler material according to the invention is suitable for the production of a filter with a uniform, white and flat face on the mouth side, it also being possible to achieve a selective filtration effect on phenols.

By using a filter and / or filler material based on cellulose acetate filaments, on the one hand filter rods, especially for cigarettes, can be produced which have demonstrably to be emphasized properties regarding specific retention phenomena with regard to the discussion regarding smoking and health. For example, a cellulose acetate filter filters nitrosamines and phenols that are harmful to health far more efficiently than condensate and nicotine. In addition, the smoke taste of the tobacco mixture commonly used today, such as "American Blend", "German Blend" and "Virginia" in combination with a filter rod made of cellulose acetate, is judged to be the most pleasant by the smoker. Another advantage of a cellulose acetate filter rod that should not be underestimated is the optical homogeneity of the cut surfaces of the filters.

Since the filter and / or filler material according to the invention is at least partially formed from hollow cellulose acetate filaments which serve as filler material, the draw resistance and the filtration performance can be varied over a wide range in filter rods made from the material according to the invention.

In particular, it has been shown that a filter material which at least partially consists of hollow cellulose acetate filaments has an improved thermal cooling effect. It was found that through the use of hollow-shaped cellulose acetate filaments as filler material still have a very low filter effect, ie retention effect for the suspended matter and gases to be removed. It is assumed that this effect is achieved by changing the surface or the flow of the gas to be cleaned or the air through the hollow cellulose acetate filaments in such a way that any suspended matter present in the gas or in the air is hardly retained. Another reason could be that the use of hollow cellulose acetate filaments makes it possible to achieve a different, particularly advantageous surface structure of the filter material.

The filter and / or filler material according to the invention also has the advantage that it enables, in particular, adjustable cooling of a heated particle-laden gas (in particular aerosol), so that the temperature of the gas, aerosol or vapor absorbed by the user of a smoking article or HNB product can be reduced in a targeted manner. By varying the proportion of the hollow cellulose acetate filaments in the filter and / or filler material, the desired cooling effect can be adapted to the specific application.

It is also important to mention that the hollow-shaped cellulose acetate filaments (= hollow fibers) in the filter and / or filler material according to the invention are essentially flowed around and flowed through less. From geometrical considerations it can be seen that the fiber-to-fiber distances are significantly larger than the lumen (hollow portion) of the hollow fiber. The viscosity of the aerosol (essentially air) then helps to choose the path of least resistance (i.e. it flows between the filaments and not through each individual filament.

In other words, in the case of the filter and / or filler material according to the invention, the surface effective for filtration is by no means maximized, since the flow does not flow through the hollow cellulose acetate filaments in the filter and / or filler material.

In particular, the hollow cellulose acetate filaments can thus have kinks that close the lumen of the hollow cellulose acetate filaments without this having an effect on the performance of the filter and / or filler material according to the invention with regard to the set target parameters.

In particular, it should be mentioned in this connection that the hollow-shaped cellulose acetate filaments made as hollow fibers do not have to be hollow throughout, but can also be partially closed by kinks. They can also deviate from an ideal circular shape.

In embodiments of the invention it is provided that the hollow-shaped cellulose acetate filaments of the filter and / or filler material serve on the one hand as a carrier material and on the other hand as a cooling material. Since the hollow-shaped cellulose acetate filaments also serve as a carrier material, particularly compact mouthpieces can be produced in which the dimensions of the smoking article do not have to be increased.

It is conceivable, for example, for the filter and / or filler material to have areas with hollow cellulose acetate filaments and non-hollow cellulose acetate filaments that adjoin one another in the longitudinal direction of the mouthpiece. A mixture of hollow and non-hollow cellulose acetate filaments would also be conceivable. Alternatively or in addition to this, the hollow-shaped and non-hollow-shaped cellulose acetate filaments can be arranged in layers and then folded. In this way, the largest possible area of the hollow-shaped cellulose acetate filaments serving as cooling material is possible, as a result of which the particle-laden gas can be cooled better.

The filter and / or filler material can be introduced into the smoking article in such a way that in particular the hollow cellulose acetate filaments are arranged essentially along the direction of flow of the particle-laden gas or the aerosol. In this way it can be achieved that the filter and / or filler material causes only a reduced pressure loss when the user is sucking on the mouthpiece, so that the user does not perceive the suction to be strenuous or uncomfortable. By varying the alignment of the hollow cellulose acetate filaments with respect to the direction of flow of the particle-laden gas or the aerosol, the tensile resistance of the filter and / or filler material can be varied over a wide range and adapted to the particular application.

By varying the proportion of the hollow and non-hollow cellulose acetate filaments in the filter and / or filling material and / or by adjusting the orientation of the hollow and non-hollow cellulose acetate filaments with respect to the flow direction of the particle-laden gas or the aerosol in the filter and / or or filling material is varied, not only the cooling and filtration performance, but also the draw resistance of the filter and / or filling material can be adjusted.

Alternatively, it is provided that the filter and / or filler material consists only of hollow cellulose acetate filaments. Then comes the filter and / or filler material to provide an optimal cooling performance with a reduced filtration performance.

Another embodiment of the filter and / or filler material according to the invention provides that the filter and / or filler material is arranged as a separate segment in the flow direction of the particle-laden gas or the aerosol in front of the mouthpiece. The separate segment can have a variety of shapes. A preferred cylindrical shape is described by way of example, to which the invention is not intended to be limited. Conventional smoking articles are mostly designed essentially cylindrical. The separate segment can also be arranged in front of a possible filter in the flow direction of the particle-laden gas. The filter and / or filler material, which serves as a cooling device and is designed as a separate segment, can for example consist entirely of hollow-shaped cellulose acetate filaments.

It is also conceivable that the separate segment has a cover, for example made of paper or a type of housing, so that the hollow-shaped cellulose acetate filaments serving as cooling material can be encapsulated. The casing or the housing has an inlet opening and an outlet opening for the particle-laden gas or the aerosol, through which it flows due to the suction by the mouthpiece by the user. The hollow-shaped cellulose acetate filaments used as cooling material can, for example, also optionally be attachable in or on the smoking article in encapsulated form. In this way, a user has the option of only cooling the particle-laden gas when he deems it necessary.

As already stated, in particular the tensile resistance of a filter rod formed from the filter material according to the invention can be varied over a significantly larger range by varying the proportion of hollow cellulose acetate filaments in the filter material.

In summary, it can be said that by using a filter material which consists at least partially of hollow cellulose acetate filaments, the tensile resistance and the filtration performance can be adapted over a wide range to the respective requirements, much more flexibly than is the case with conventional filter materials based on cellulose acetate filaments Case is. In addition, a cooling effect can be set variably.

In particular, the present invention allows mouthpieces or filters to be formed from cellulose acetate, which is normally in the form of a strand of essentially longitudinally directed continuous filaments, the continuous filaments preferably being crimped so that short regions of the individual filaments are irregularly shaped non-parallel, converging and diverging directions compared to the predominantly longitudinal direction of the strand are arranged.

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

The ripple index I _x is a measure of the intensity of the ripple. The curl index of a filter tow is determined by a tensile test (relationship between force and elongation). It is defined as the ratio of the stretched length L ₂ under test load minus the initial _{length to the initial length under preload L 1} : $${\text{I.}}_{\text{x}}=\left({\text{L.}}_2-{\text{L.}}_1\right)/{\text{L.}}_1\ast 100\%$$

The test load is 25 N and the preload is 2.5 N. The clamping length is 250 mm. The crimp index is determined in a tensile test with a constant expansion speed of 300 mm / min on a G02 device from Borgwaldt GmbH, Hamburg. 10 individual measured values are recorded per measurement. The test is carried out under a standard climate: 20 ° C and 60% relative humidity.

The filter material according to the invention is preferably in the form of a filter tow consisting of endless, crimped cellulose acetate filaments, and in particular cellulose-2,5-acetate filaments. To produce the filter tow, a solution of approx. 30% cellulose-2,5-acetate in acetone is pressed through special spinnerets, the acetone evaporates in a spinning shaft by blowing heated air into a large number of filaments (1,000 to 35,000) summarized in a band and then curled the shrub chamber. The product is then dried, filled into storage containers and finally pressed into bales weighing between 300 and 600 kg.

To spin the spinning solution, spinnerets are used which are designed to spin hollow cellulose acetate filaments and / or cellulose acetate staple fibers.

After the filter tow bales have been transported to the filter or cigarette manufacturer, the filter tow is removed from the bale and placed on a Filter rod machine, for example in the publication U.S. 5,460,590 A described, processed into filter rods. The filter tow is stretched in a stretching device, provided with an additive used to glue the filaments and then, after a three-dimensional fuse has been formed, introduced into the format part with the help of an inlet funnel, where it is transversely axially compressed, wrapped with paper and cut to the final length of the filter rods cut.

The additive applied to bond the filaments can be a high-boiling solvent for cellulose acetate, such as glycerol triacetate (triacetin), which briefly dissolves the surface of the filaments after its application. Wherever two filaments happen to come into contact with each other, there will be a firm bond point some time afterwards, as the excess additive migrates into the fiber surface, causing the previously liquid drop of solution to solidify. After a storage period of less than an hour, mechanically strong, three-dimensional cross-linked filter rods, which are also known as "space filters" and which have a low packing density of usually 20 mg / ml to 90 mg, are obtained due to the aforementioned migration of the hardening agent / ml, preferably 30 to 70 mg / ml and more preferably 40 to 60 mg / ml. Due to their hardness, these filter rods can be processed without difficulty on modern cigarette machines at high speeds.

Investigations have shown that by using hollow cellulose acetate filaments in the filter material, the filtration performance of room filters can be reduced and the cooling performance can be increased while maintaining the specifications such as length, diameter, tensile resistance and filament titre.

By increasing the proportion of hollow fibers (hollow cellulose acetate filaments) in the filter material accordingly, the draw resistance can be kept in the required low range despite the increase in the cooling capacity and the reduction in the filter capacity, without the filament titer increasing.

In particular, according to implementations of the filter material according to the invention, it is provided that the proportion of hollow-shaped (hollow) cellulose acetate filaments in the filter material is between 20 to 100% and preferably between 40 to 100% and even more preferably - depending on the application - between 70 to 100%.

In particular, the proportion of hollow parts in the filter material is preferably 25 to 90% and preferably 50 to 80%. This hollow portion makes a decisive contribution to the filtration performance on the one hand and to the reduction of the tensile resistance on the other hand, which can only be achieved due to a corresponding portion of hollow fibers in the filter material, but not in the case of closed filaments. The hollow portion corresponds to the ratio of the "hollow" area of the filter material to the "total" cross-sectional area of the fibers.

In this context, it should be mentioned that the filter material according to the invention is also particularly characterized in that the filament diameter of the cellulose acetate filaments is significantly larger than the filament diameter of other (synthetic) hollow fibers whose filament diameter is in the range between 10 and 30 μm. In contrast, the filament diameter of the hollow cellulose acetate filaments is in the range between 30 to 150 µm (outside diameter), and preferably between 50 to 120 µm (outside diameter), and more preferably between 60 to 100 µm (outside diameter). In this way, the hollow portion can be increased and thus the specific filtration performance of the filter and / or filler material according to the invention can be significantly reduced, while at the same time the cooling performance of the filter and / or filler material according to the invention is increased.

The invention also relates to a cigarette filter made from a filter material of the aforementioned type.

According to non-limiting embodiments, either a thermoplastic cellulose ester fiber material or, in the case of a non-thermoplastic cellulose ester, a water-soluble adhesive can be used to produce a filter according to the invention. For the first case of a thermoplastic cellulose ester fiber material, a distinction can be made between two cases. In the first case, the fiber material is made from a naturally thermoplastic cellulose ester, such as cellulose acetobutyrate. In this, the filter tow can be processed into filters according to the invention without further measures. In the case of a non-thermoplastic starting polymer, such as cellulose-2,5-acetate, this must be thermoplasticized by adding a suitable plasticizer.

To produce the filter according to the invention, a filter tow is pulled off a bale, pneumatically spread out and stretched according to the method customary for space filters.

In the context of the teaching according to the invention, the acetate weight can be a maximum of 5 mg per mm filter length and at least about 2 mg per mm filter length and is in particular about 3 to 4 mg per mm filter length. If the maximum value of 5 mg per mm of filter length is exceeded, then a such a product is not sufficiently economical. A minimum value of approximately 2 mg per mm of filter length is preferably maintained. If this value is not reached, the required hardness of the cigarette filter of a minimum of 88% can no longer be maintained according to the state of the art.

The tensile resistance within the scope of the inventive teaching can be a maximum of 2 mm daPa per mm filter length and at least about 0.1 daPa per mm filter length and is in particular 0.2 daPa to 1 daPa per mm filter length. A tensile resistance of 0.3 daPa to 0.7 daPa per mm of filter length is particularly preferred. A minimum value of 0.3 daPa per mm of filter length is preferably maintained. If this value is not reached, the required hardness of the filter of a minimum of 88% can no longer be maintained according to the state of the art.

• Gemäß einem ersten Aspekt betrifft die Erfindung ein Filter- und/oder Füllmaterial für Mundstücke zur Verwendung mit Rauchwaren oder HNB-Produkten, wobei das Filter- und/oder Füllmaterial auf Celluloseacetatfilamenten basiert, welche zumindest teilweise als hohlförmige und/oder rohrförmige Celluloseacetatfilamente ausgebildet sind.

Some aspects essential to the invention are summarized below:

• According to a first aspect, the invention relates to a filter and / or filler material for mouthpieces for use with smoking goods or HNB products, the filter and / or filler material being based on cellulose acetate filaments which are at least partially designed as hollow and / or tubular cellulose acetate filaments.

According to a variant embodiment of the filter and / or filler material, the cellulose acetate filaments have hollow and in particular crimped endless cellulose acetate filaments and / or hollow and in particular crimped and cut endless cellulose acetate filaments.

According to one embodiment of the filter 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 one embodiment of the filter and / or filler material, the cellulose acetate filaments are formed from a thermoplastic cellulose material, the cellulose acetate filaments, if a plasticizer is included, containing this evenly distributed, and / or where a water-soluble adhesive is present on the surface of the cellulose acetate filaments.

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

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

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

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

According to one embodiment of the filter and / or filler material - based on a section orthogonal to the fibers of the filter and / or filler material - the hollow portion in the filter and / or filler material is 25% to 90% and preferably 50% to 80% .

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

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

According to an embodiment of the filter and / or filler material, the hollow cellulose acetate filaments are spaced apart in an unregulated arrangement, the cellulose acetate filaments being crosslinked and the connecting cellulose acetate filaments being looped and / or interlocked with one another.

According to one embodiment of the filter and / or filler material, a binder, in particular an organic or inorganic binder, is also provided to hold the cellulose acetate filaments together.

According to a further aspect, the present invention relates to a mouthpiece for use with tobacco products or HNB products, the mouthpiece having a filter and / or filler material of the aforementioned type according to the invention.

According to a further aspect, the present invention relates to a cigarette filter or a cigarette filter element which has a filter and / or filler material of the aforementioned type according to the invention.

• • die Faserdichte des Filter- und/oder Füllmaterials beträgt zwischen 10 bis 70 kg pro m³ und vorzugsweise zwischen 20 bis 70 kg pro m³ und noch bevorzugter zwischen 40 bis 60 kg pro m³;
• • der Zigarettenfilter oder das Zigarettenfilterelement weist eine Filtronahärte von mindestens 88 % und vorzugsweise eine Filtronahärte von 88 % bis 95 % und noch bevorzugter eine Filtronahärte von 90% bis 93 % auf;
• • der Zigarettenfilter oder das Zigarettenfilterelement weist einen Zugwiderstand von mindestens 0,1 daPa pro mm Filterlänge und vorzugsweise einen Zugwiderstand von 0,2 daPa bis 1,0 daPa pro mm Filterlänge und noch bevorzugter einen Zugwiderstand von 0,3 daPa bis 0,7 daPa pro mm Filterlänge auf;
• • das Filter- und/oder Füllmaterial weist einen Weichmacher auf, wobei der Weichmachergehalt zwischen 1 % bis 40 % liegt.

According to variant embodiments of the cigarette filter or the cigarette filter element, at least one feature of the following features is implemented:

• The fiber density of the filter and / or filler material is between 10 to 70 kg per m ³ and preferably between 20 to 70 kg per m ³ and even more preferably between 40 to 60 kg per m ³ ;
• The cigarette filter or the cigarette filter element has a Filtrona hardness of at least 88% and preferably a Filtrona hardness of 88% to 95% and more preferably a Filtrona hardness of 90% to 93%;
• • the cigarette filter or the cigarette filter element has a tensile resistance of at least 0.1 daPa per mm filter length and preferably a tensile resistance of 0.2 daPa to 1.0 daPa per mm filter length and more preferably a tensile resistance of 0.3 daPa to 0.7 daPa per mm of filter length;
• • the filter and / or filler material has a plasticizer, the plasticizer content being between 1% and 40%.

According to variant embodiments of the cigarette filter or the cigarette filter element, an in particular capsule-shaped or capsule-like flavor release element is also embedded in the filter and / or filler material.

According to variant embodiments of the cigarette filter or the cigarette filter element, the cigarette filter or the cigarette filter element has solid cellulose acetate filaments in addition to the hollow cellulose acetate filaments.

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

According to a further aspect, the present invention relates to a method for producing a filter and / or filler material for mouthpieces for use with smoking goods or HNB products, the filter and / or filler material preferably consisting of cellulose acetate filaments and / or cellulose acetate staple fibers, with a solution of cellulose acetate with an acetyl number of at least 53% in acetone is pressed through a spinneret with several openings, and then optionally the cellulose acetate filaments are cut into cellulose acetate staple fibers and a large number of the cellulose acetate filaments and / or cellulose acetate staple fibers thus obtained, which are optionally combined into a filter tow is crimped, the spinneret through which the solution of cellulose acetate is pressed is designed such that hollow cellulose acetate filaments are spun.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 5460590 A [0080]

Claims (23)

Filter and / or filler material for mouthpieces for use with tobacco products or HNB products, the filter and / or filler material being based on cellulose acetate filaments which are at least partially in the form of hollow and / or tubular cellulose acetate filaments. Filter and / or filler material after Claim 1 wherein the cellulose acetate filaments have hollow and in particular crimped continuous cellulose acetate filaments and / or hollow and in particular crimped and cut continuous cellulose acetate filaments. Filter and / or filler material after Claim 1 or 2 , wherein the crimp index of the cellulose acetate filaments is between 10% and 60%, in particular between 20% and 50%. Filter and / or filling material according to one of the Claims 1 to 3 wherein the cellulose acetate filaments are formed from a thermoplastic cellulose material, and wherein the cellulose acetate filaments, if a plasticizer is included, contain this evenly distributed; and / or wherein a water-soluble adhesive is present on the surface of the cellulose acetate filaments. Filter and / or filling material according to one of the Claims 1 to 4th , the plasticizer content being between 1 and 40% if a plasticizer is used. Filter and / or filling material according to one of the Claims 1 to 5 , in the case of the use of a plasticizer this is triacetin, triethylene glycol diacetate and / or citric acid diethyl ester. Filter and / or filling material according to one of the Claims 1 to 6th , wherein the cellulose acetate filaments have a fineness between 5 to 30 denier, preferably between 10 to 25 denier and even more preferably between 15 to 20 denier. Filter and / or filling material according to one of the Claims 1 to 7th , the total denier of the filter and / or filler material being between 4,000 and 40,000 denier and preferably between 6,000 and 30,000 denier. Filter and / or filling material according to one of the Claims 1 to 8th , wherein - based on a section orthogonal to the fibers of the filter and / or filler material - the hollow portion in the filter and / or filler material is 25% to 90% and preferably 50% to 80%. Filter and / or filling material according to one of the Claims 1 to 9 , wherein the filament diameter of the cellulose acetate filaments is in a range between 30 to 150 µm (outside diameter), and preferably in a range between 50 to 120 µm (outside diameter), and more preferably in a range between 60 to 100 µm (outside diameter). Filter and / or filling material according to one of the Claims 1 to 10 wherein the mass fraction of hollow cellulose acetate filaments is 20 to 100%, preferably 50 to 100% and more preferably 70 to 100%. Filter and / or filling material according to one of the Claims 1 to 11 , wherein the hollow cellulose acetate filaments are spaced apart in an unregulated arrangement, and wherein the cellulose acetate filaments are crosslinked, the connecting cellulose acetate filaments being looped and / or interlocked with one another. Filter and / or filling material according to one of the Claims 1 to 12th wherein a binder, in particular an organic or inorganic binder, is also provided for holding the cellulose acetate filaments together. Mouthpiece for use with tobacco products or HNB products, the mouthpiece being a filter and / or filler material according to one of the Claims 1 to 13th having. Mouthpiece after Claim 14 wherein the fiber density of the filter and / or filler material is between 10 to 70 kg per m ³ and preferably between 20 to 70 kg per m ³ and even more preferably between 40 to 60 kg per m ³ ; and / or wherein the cigarette filter or the cigarette filter element has a Filtrona hardness of at least 88% and preferably a Filtrona hardness of 88% to 95% and more preferably a Filtrona hardness of 90% to 93%; and / or wherein the cigarette filter or the cigarette filter element has a draw resistance of at least 0.1 daPa per mm filter length and preferably a draw resistance of 0.2 daPa to 1.0 daPa per mm filter length and more preferably a draw resistance of 0.3 daPa to 0, 7 daPa per mm of filter length; and / or wherein the filter and / or filler material has a plasticizer, the plasticizer content being between 1% and 40%. Mouthpiece after Claim 14 or 15th wherein an in particular capsule-shaped or capsule-like flavor release element is embedded in the filter and / or filler material. Mouthpiece according to one of the Claims 14 to 16 , the filter and / or filler material in addition has solid cellulose acetate filaments to the hollow-shaped cellulose acetate filaments. Cigarette filter or cigarette filter element, which or which a filter and / or filler material according to one of the Claims 1 to 13th having. Cigarette filter or cigarette filter element Claim 18 wherein the fiber density of the filter and / or filler material is between 10 to 70 kg per m ³ and preferably between 20 to 70 kg per m ³ and even more preferably between 40 to 60 kg per m ³ ; and / or wherein the cigarette filter or the cigarette filter element has a Filtrona hardness of at least 88% and preferably a Filtrona hardness of 88% to 95% and more preferably a Filtrona hardness of 90% to 93%; and / or wherein the cigarette filter or the cigarette filter element has a draw resistance of at least 0.1 daPa per mm filter length and preferably a draw resistance of 0.2 daPa to 1.0 daPa per mm filter length and more preferably a draw resistance of 0.3 daPa to 0, 7 daPa per mm of filter length; and / or wherein the filter and / or filler material has a plasticizer, the plasticizer content being between 1% and 40%. Cigarette filter or cigarette filter element Claim 18 or 19th wherein an in particular capsule-shaped or capsule-like flavor release element is embedded in the filter and / or filler material. Cigarette filter or cigarette filter element according to one of the Claims 18 to 20th , wherein the cigarette filter or the cigarette filter element has solid cellulose acetate filaments in addition to the hollow cellulose acetate filaments. Use of the filter and / or filling material according to one of the Claims 1 to 13th in tobacco products or in HNB products. Method for producing a filter and / or filler material for mouthpieces for use with smoking goods or HNB products, in particular a filter and / or filler material according to one of the Claims 1 to 13th , which consists of cellulose acetate filaments and / or cellulose acetate staple fibers, wherein a solution of cellulose acetate with an acetyl number of at least 53% in acetone is pressed through a spinneret with several openings, and then optionally the cellulose acetate filaments are cut into cellulose acetate staple fibers and wherein a plurality of the thus obtained Cellulose acetate filaments and / or cellulose acetate staple fibers are combined to form a filter tow, which is optionally crimped, the spinneret through which the solution of cellulose acetate is pressed is designed such that hollow cellulose acetate filaments are spun.