DE1028926B - Filter element for tobacco smoke - Google Patents

Description

It is also known to hold the fibers of a filter element together with a binding agent. This cohesion can be achieved by dipping the • optionally crimped fibers into the binder or by spraying the binder on to 35 the fibers can be achieved. Thereby one will fully educate and this strand by a conical permanent envelope by the binder or only Form nozzle to pull the strand by means of a cohesion at certain points at intervals Solution achieved with a holding the fibers together along the fibers or threads. Such Coat too. Binders, especially bitumen, rubber compounds,

There are also filter elements for cigarettes containing 40 nitrocellulose and the like, decompose at proportionally, at which the filter material by means of a moderately low temperature, so that; their anwert jacket is held together, which is made from plant manure as a smoke filter from hygienic, flavor glues or water-soluble, synthetic glues, borrowed or odor reasons is impossible.
for example cellulose derivatives. This is the underlying object of the invention

Solutions and glues are sensitive to moisture. 45 an effective, moisture-resistant, pressure-resistant When storing a cigarette for a long period of time or when the filter element is to be produced and thereby filter smoking the same can be summarized a moistening of the material that through the to-filter element, be it due to the summary contained in the tobacco no disturbing influences on moisture, by the humidity or by kicking. According to the invention this object is achieved Do not avoid the saliva of the mouth.'Therefore take 50 by loosening the fibers or threads through a these known filter elements are partly a sticky solvent or fused by heat. Texture, to some extent they also dissolve. The fibers or threads of the outer layer of the These known filter elements can also push bundles can in this case essentially over their be sensitive, so that the pressed entire length are fused together, worn 507/85

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created by a coat. This coat is with the In a preferred embodiment of the invention

The filter element consists essentially of fibers or threads resting against it at intervals

merged. The advantage of the invention is that the longitudinally oriented fibers made of acetyl

Fibers or threads by no binding agent to cellulose and / or from aligned fibers

be held together. The fibers or threads 5 are modified, for example containing plasticizers

are melted by a solvent or a soft acetyl cellulose, which is a coating of

Makers or loosened by heat, so that the zenen fibers.

Glue the fibers together. When using the filter element is manufactured by im a solvent this evaporates. Any substantial one continuous strand of fiber through one unfavorable effect passed through a glue or an io conical tube and the formed strand Binder is produced, can not be exposed to heat and / or solvents appear. and / or a plasticizer, in particular on its surface, in order to match the filter properties, is exposed in such a way that the fiber parts such filter elements from a mixture of the jacket of the combined strand itself Filamentary or fibrous acetyl cellulose and soft 15 completely unite with each other and on this Maeherhaltiger Acetylcellulose are produced in such a way as a continuous outer covering or skin that they form a corresponding porosity, integrity, which surrounds the inner fiber mass and is at the same time shaped Composition, appropriate strength. The one formed in this way Speed, stiffness and elasticity as well as the filter's own strand is then converted into individual cylindrical elements have shafts that allow their use in cigarettes of a certain length, which have the corresponding rigid Pipes or in cigarette or cigar holders in order to be able to maintain their shape, make possible. The manufacture of such filters- cut.

elements is also simple and cheap. Under the term "strand" are heden-like, According to the invention - from the freely lead- continuous fiber strands or combed strands the above apart from the gaps - a homogeneous one. 25 to understand how they are exemplified more uniformly cylindrical body with permeable way in the yarn production from the card or porous end faces. The fibers should run and where the fibers are essentially be sufficiently densely packed so that one is aligned along the course of the Hedenzug, Speaking effectiveness as a filter is guaranteed. However, the invention becomes clear with reference to the drawing on the other hand, such distances from one another are described in more detail. It shows

indicate that the filter element to the air flow Fig. 1 is a schematic and graphical representation

does not offer any resistance worth mentioning. management form of a device by means of which a

Instead of the fibers that have melted together, the fiber strand is gathered, heated and

or threads formed sheath can however be melted into

As is known, the bundle of a paper 35 Fig. 2 is a schematic vertical section of a

coat or the like. further embodiment of a device according to

To make the invention understandable, be to the invention in which to unite the fibers in the

only in a general way the production of a fiber strand and on the surface of the fiber strand

characteristic embodiment of a filter element- liquid chemicals, such as plasticizers, ments described according to the invention. Fibrous 40 can be used.

Acetyl cellulose material is in the form of a Fig. 3 shows a longitudinal section of a device for

Bundle brought uniform cross-section, forming the fiber strand, with the hot gases to

the fibers of the bundle are generally used in longitudinal fusing of the fibers,

direction run parallel, but short parts of Fig. 4 in an enlarged scale a partial section individual fibers run in any directions 45 a with a filter mouthpiece according to the invention

can. This fiber material is now a manure-provided cigarette,

Filter element processed by the acetyl cellulose- Fig. 5 schematically shows a longitudinal section of a pre-fiber at part of their points of contact with the direction for the production of filter elements according to FIG are fused together, so that the fiber of the invention, when spray nozzles for spraying strand forms a cohesive unit. 50 of a plasticizer are used, The union can, for example, by means of interweaving. kurag of heat on thermoplastic components of the direction shown in FIG. 5, but with additional Fiber material are effected. Preferably, means for completing the union of the a union also through partial dissolution or fibers and to the formation of the outer fiber skin a solution in the early stages of the fibrous 55 should be applied.

Material are effected, with parts of the individual The execution fibers shown in the drawing can be brought into a state in which they can form devices for the production of filters in similar dissolved or plastic material masses of the elements can in principle be divided into two types adjacent fibers flow. They are preferably divided as shown, for example, in FIGS. 3 and 5 the filters from a continuous fiber strand, the 60 are shown.

either a hede of a continuous fiber yarn in the device shown in FIG or a top of carded staple fiber be a fiber strand 31, which to a corresponding can, formed. The fiber strand material is treated as a percentage at a relatively low temperature, that at least some of the fibers contain fibers that become plastic or softened, Speaking adherence to its surface is conducted through a device in which the fibers are rich, and then by means of a condenser mass through hot, inert gases over the entire area tube or the like, through which you run the strand, cross section of the strand is heated. Strand 31 lets, combined, with the fibers firmly attached to one another in a non-combined state by a are pressed against the other and point-wise ve-r guide element 39 in one by a · bell unite or stick together. 70 part of the guide element 39 which is enlarged in a shape

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and a funnel-shaped widening part 30. The device according to FIG. 5 is similar to that in FIG. 3 a tube 38 formed chamber passed. In the device shown. The union of the fibers formed by the guide element 39 and the part 30 is in this case not conditioned by heating In the chamber, the fiber strand is affected, but primarily through a liquid one heated gas stream, for example an air. Stick- 5 plasticizers. A strand 51 of acetyl cellulose fibers substance or carbon dioxide stream, exposed. The occurs in the mouth 57 of an atomizer part 30 overlaps the guide element 39 so that a device. The mouth 57 serves only as a one-ring channel is formed by which the heated gas regulates the strand course, it presses the fiber stream, as indicated by the arrows 32, but not essentially in the strand. Behind Chamber enters. In the chamber is the fiber strand io the mouth 57 is the fiber strand in a still existed with a plasticizer in its loose, not combined, spray chamber 52, so that the hot gas stream sprays without significant. It should be noted that the strand Resistance due to the spaces between the in Fibers can pass through and the fiber strand is in a relatively loose state, so that the probably arranged uniformly on its surface as well as in its core 15 at different points in the chamber warmed up. Due to the heating by means of a neten atomizer directed onto the strand Gas flow, the easily melting parts are nozzle 53 the atomizer on, in and through the of the fiber strand at least partially drive into a first strand, so that all points of the fiber material softened or molten state exposed to the plasticizer. The strand works been. The fiber strand now runs continuously through the chamber 52 through the ver 20 and follows it narrowed tube 38, where he cut together on the desired cross-traversal of the same in a conical shape summarized and in the corresponding running pipe 54 and is then in the pipe 55 Is brought into shape. After the fiber strand has been put together to its desired final diameter Has passed through the shape-determining tube 38, taken. The inner diameter of the tube 55 is he enters a second chamber 33, in which the 25 is about a fifth of the diameter of the strand, Fibers are cooled and solidified so that when it enters the spray chamber 52. The structure of the fiber strand has a uniform, lead- The mode of action of the plasticizer is now thieving, assumes a cylindrical shape. The second is that the fibers of a partial or constituent chamber 33 can be subjected to under- going solution through an opening 34 so that it, pressure are set so that the heating of the 30 when the fiber mass in the tube 55 together-fiber strand causing gases from the fiber mass is summarized, with their outer layers in one another subtracted from. The fiber strand enters through an overflow and at a large number of loading exit opening 35 from the chamber 33. The points of contact stick together or iii-fiber strand canoe flow after leaving the apart. In this way the fiber duct opening becomes 35 are still further cooled, 35 stranded to one out of the mouth of the tube 55 auser formed in the form given to him by the tube 38 stepping cylindrical rod 56, which as remain. From the exit opening 35 a structural unit emerges more or less its continuation cylindrical filter rod of one unit of measurements and retains its shape and its borrowed structure, the fibers of which are essentially fibers permanently connected to one another at many points Run the length of the strand and are welded to the 40.

Points of contact over the entire cross-section The devices of the strand shown in Figures 1 and 2 are welded together. The outlines are mainly used for the production of a pressure "filter rod" is intended to indicate that the fiber mass of a filter rod is somewhat different from that in such a state that the rod is inde- pendent of the invention. FIG. 6 shows the embodiment of a device that is suspended from any carrier and that retains its shape and shape according to the measurements made so far. The filter rod experience has proven to be the best. is nonetheless of course not rigid, but on the contrary, the device shown in Fig. 1 becomes flexible and elastic. a fiber strand 11 in a conically narrowing The device shown in Fig. 3 is advantageous pipe 12 passed. Due to the funnel-like design, it can be used in cases in which the temperature of the tube 12 can be used in radial directions without adverse effects to achieve its desired end diameter, by means of which the fibers are partially or fully compressed. The tube 12 has at its failure in a plastic state transition end 13 can be constant over a short distance. The fiber mass can have a mixture of diameter and at this point is made of plasticized or non-plasticized acetyl 55, an electrical coil 14 or a similar cellulose. Such a mixture of the fiber-end material, such as a steam-flowed coil, material has heated up for processing in the dielectric device or the like in FIG. 1. The device shown has also proven its worth. With regard to the temperature of the short piece of the tube 12 and the device shown in FIG. 3, the speed of passage of the fiber strand should also be mentioned, so that the fiber bundles are so coordinated and adjusted, summarizing tube 38 with additional heat that all swelling on the surface of the fiber strand, for example an electrical heating coil, lying fibers can be provided heated to their melting point so as to be complete, so that the fibers to a closed melting of the surface of the fiber strand to a jacket or a continuous Fuse skin, guarantee. The hot air chamber can also by 65 which surrounds the fiber strand. After the fiber any arbitrary means, for example by extrusion through the in Fig. 1 illustrated \ ^r orrichtung a fiber strand enclosing spiral has passed, it can be replaced, wherein the inner shell of the cutting machine are supplied to a copper pipe, not shown, that the continued Coil with serving as nozzles for the heated gases running rod in individual, ge-bores provided by a jacket. 70 filter elements surrounded by melted fibers

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the correct length. These filter elements both in the surface area and can then directly in the usual machines also inside. The percentage of the Used to make cigarettes, the fibers can be bonded to the jacket and in the core modified as substantial areas wrapped in the cigarette paper where mouthpiece to be inserted into the cigarettes. 5 filter elements with different physical

The device shown in Fig. 2 operates in the kaiischen properties result. At a pre-essential according to the same method as the preferred embodiment, the filter element has a direction according to FIG. 1, with the one exception that the structure in which the lying on the surface the conically converging tube 26 are united on Zimmer fibers to form a jacket, which the temperature is maintained and that the fusing together of the fibers of the core, which, however, should not lie loosely, of the fibers on the surface of the fiber strand but connected to one another or to the sheath by means of one on the combined strand 21, holds together.

Acting solvent atomizer as appears from the above description will. The atomizer nozzles 27 of the atomizer are the essential features of the process device are behind the outlet opening of the 15 for the production of the embodiments of filter tube 26 arranged. The agent to be atomized elements according to the invention, in which above all the penetration of the agent into the fiber can be a surface bond the fibers of the sheath strand promoting substance such as acetone contain. Who united with one another, the following:

summarized and pollinated strand can, if 1. First a fiber strand is formed in which

It is desirable that the fibers are then aligned in an oven or the like in such a way that they are elevated in the water Temperatures are exposed to the borrowed run lengthways. The fiber strand To support staff formation. It also turns out to be a compact mass of fibers, which is a convenient, the fiber strand before it is agreed, usually circular or oval run into the pipe 26 with the solvent to be loaded cross-section, summarized, spray. 25 2. The preformed fiber strand is through

The embodiment shown in Fig. 6 of a heat or similarly acting measures so beVorrichtung generally provides the most that the fiber mass becomes a cylinder-preferred filter element. The device is solidified to the body of a structural unit similar to the device shown in FIG. They or to such a welded, that is, contains only an additional heating element 68, formed by means of 30 formed fiber bundle, the fibers of which the jacket zone of the combined fiber their contact points are partially welded, strand is heated so that the fibers on the upper -... having and a certain constant cross-sectional area "of the strand fully comparable with each other, the bonding of the fibers at their Berühschmelzen and a continuous dense skin or approximately score is formed by dissolving or fusing L ^T mhüllung in the in Figure 6 is shown 35 the At or in the vicinity of the surface of the device, the fiber strand 61 is inserted into the mouth of the bundled strand with fibers 67 of the atomizer chamber 62, and acts in such a way that a uniform, continuous, smooth jacket of the atomizer chamber 62 is formed by the atomizer nozzle Lanier sprayed the expression "loosening" 63. The strand then runs Finally, in the sense used here, the formation of a conically converging tube 64 and, in the sticky part 65, which opens into the fleece element 68, which ensures adhesion, reaches the state of the desired final diameter which is initially or easily bonded. The heating element fibers by loosening or inserting or releasing is coordinated with the corresponding throughput speed of loosening the fibers or parts of the fiber strand in such a way that the surface thereof is essentially understood. The cylindrical filter rod of the fiber strand, which accumulates in continuous lengths only of the fibers 45 lying on the surface, is heated to such an extent that the fiber strand can be cut into a continuous outer skin, the shape of which is sanitary-melted fibers in terms of size receives. and cross-section the different types of cigarette

Rescue eggs with a filter element according to the invention, cigar and cigarette holders and pipes The cigarette provided in the usual way is available in the various types of machines for example shown in FIG. That can be adapted by-making cigarettes. In going outer skin 71 of molten fibers in some cases it is desirable that those in the core having, in its structure uniform filter of the filter element located fibers stronger miteinelement 72 is to be united to the tobacco core 73 of the cigarette, in particular with one another attached and will be fused by an extension of the 55, as this is by a the fiber tobacco core wrapping cigarette paper 74 accomplished on bundle encompassing heating element this kept. The mouthpiece of the cigarette can be can. In this case it is necessary that be stiffened by a cork plate 75 or the like. the fibers in the core of the strand to the necessary The given embodiments show that temperature can be brought without the fibers the filter elements exceed the required 60 on the surface inadmissibly far above the nest and proportions in their dimensions and melting point heated or if a plasticizer Properties can be customized. In each one or a solvent can be used, one too However, if the filter element is to be exposed to the strengthening solution, findv.'ig a structural unit of cylindrical shape in all cases where the treatment is to

made of acetylcellulose fibers, which are essentially due to heating or to the E'n- ■ are aligned along the axis and the effect of a solvent on the on or in the Points of contact have permanent bonds. Located near the surface of the fiber strand In all embodiments of according to the invention fibers is limited, the filter element consists of filter elements manufactured a bin in a jacket-shaped housing of the fibers to a lesser or greater extent 70, whereby the inside of the egg

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cellulose ester having a content of 38.0 to 38.7% and a hydroxyl content of 3.89 to 4.0% consists.

The acetyl cellulose fibers can contain plasticizers in 5 different proportions. Of the Plasticizers must only be non-toxic and must not provide any toxic decomposition products.

Triethyl citrate has proven to be a satisfactory plasticizer. The plasticized ones

mentes located fibers in their position in the housing to a lesser extent through welding points between the fibers and to a greater extent held by the pressure exerted by the housing and the resulting felting of the fibers will.

In the embodiments according to FIGS. 3 and 5, filter elements are manufactured by mainly the fibers lying in the fiber strand are hot

Gases or with plasticizers. io acetyl fibers can use this plasticizer for example These filter elements differ from the previous 33 percent by weight. More suitable described in that the plasticizers in the fiber bundle are tripropionine and n-isopropyl-paraane toluene sulfonamide at the points of contact of the fibers.

Union of these an additional union. Suitable filter elements were also made from one

of the fibers to a 100% plasticizer-containing fibrous acetylcellu element that is uniform in its structure supplies, which in and of itself no one loose material, such as is used for yarn production ensuring adequate dimensional stability of the element, in which the acetate is very little, the coat skin needs. Although also the degree of deheating, for example, a minimum of plasticizer the fibers held inside the fiber bundle. In those cases where a mixture of and the degree of fusion of the plasticized and non-plasticized fibers produced thereby Fibers have a noticeable effect on the stiffness, and plasticizers can also be used and elasticity of the finished filter element shows the surface of the fiber bundle being sprayed on, however, these properties also exist before it runs through the condenser tube, a corresponding change in the degree of frill as stated above, will be coordinated

Development of the fibers used or by changing mixtures of plasticizer and non-plasticizer the number and denier of the fibers containing fibers are preferred. This can be controlled softly. In those cases where the made and non-plasticized fibers are made filter element manufactured by a jacket made of any of the acetates specified above or from Melting combined, modified cellulose mixtures of the same or of mixtures of these ester fibers and a core made of a mixture of 30 acetates with other fibrous material, such as viscose, modified, for example softened cellu wool or cotton fibers, besteben. The fiberless ester fibers with non-softened fibers, mixtures of softening and non-softening fibers and those fibers contained in the fiber blend of the core were found to be useful for shaping no or little association or binding and for closing the filter element than on The elasticity 35 is most suitable. Furthermore, viscose fibers, of the filter element essentially has a function, preferably in admixture with other fibers, e.g. B. the amount of fiber contained in the sheath. A cotton to be used.

corresponding control of this amount of fiber regardless of whether the fibers are in the form of

Sheath enables, for example, a doubling of running, infinite fiber lengths or the elasticity that the tobacco core of the cigarette demonstrates from pieces of carded staple fiber. Such precise control provides, they can be used both in smooth and in for example a filter element that can be used with a large pre-curled condition. Ruffled parts in common cigarette making and fibers are preferred. Combed pieces out - packaging machines can be used. crimped staple fibers turned out to be something

The properties of the filter-filter elements of good quality, adjusted by controlling the degree of union 45 more advantageous than fibers of continuous length, of the fibers were derived from the fol, -

Rods can of course by changing the degree of heating or by changing the air flow Ratio or the total air flow can be changed, since these conditions of the 50 driving will affect the degree of union or fusing of the fibers.

That used in fibrous or filamentary form
Raw material can be made from a large number of
Cellulose derivatives, in particular cellulose esters, to 55
be composed. Acetyl celluloses were found
as particularly suitable. For example, the raw material can consist of a triacetate or a mixed ester such as an acetate propionate or
Acetate butyrate, in general, have been found to be 60
however, all acetyl celluloses are considered suitable. Particularly
Acetyl cellulose provides useful results,
how it is used for spinning yarn,
which has 38.8 to 39.2% acetyl content. It appears, however, that the acetyl content in and for material containing plasticized fibers is not particularly critical. A suitable acetyl temperature of 260 ° C is required. In general, for example, in the USA, mixtures of cellulose mixtures have been found to be described in acetyl patent specification 2,097,464. Cellulose fibers containing 15 to 50%, preferably 20%, also proved to be well suited to a raw material made from a plasticized fiber, from a propionyl content of 0.6 to 1.7%, an acetyl-70 range.

809 507/85

raw material mixtures: I. 50% crimped, cut, plasticized, spun acetyl cellulose fibers; and 50% crimped, chopped, spun acetyloellulose fibers.

II. 15% crimped, chopped, plasticized, spun acetyl cellulose fibers and 85% crimped, chopped, spun acetyl cellulose fibers.

III. 20% plasticized staple fibers made from acetyl * - cellulose and 80% non-plasticized staple fibers made from acetyl cellulose.

IV. Crimped, cut and spun acetyl cellulose fibers, which did not contain plasticized fibers.

The fiber blends specified under I and II were at temperatures of 220 to 230 ° C ~ acts, while for the specified under IV, none

As already indicated, the fibers can in their passage through the shaped tube or shaped piece in any of the various arrangements exist.

Examples of such arrangements are:

One consisting of essentially parallel fibers spun in continuous lengths Fiber strand,

one made from spun in continuous lengths, crimped and lying essentially parallel Fibers of existing strand,

a part of a lap taken from a rake or the like made of completely unoriented, cut fibers,

a carded or coated top, at

Has an acetyl content of 38 to 41%, the permissible temperature ranges of the heating pipe can be approximated by determining the melting or softening point of the plasticized fibers 5 or the melting point of the earliest softening acetyl cellulose fibers for the lower Limit the range and by determining the flash point of the fibers for the upper limit of the Area can be specified. In general, ίο the most favorable temperatures will be in the range of about 200 to 260 ° C. For example, if a fiber strand from a mixture of 50% plasticized and 50% non-plasticized fibers is treated from acetyl cellulose at 195 ° C

which the cut fibers partially aligned 15 the surface of the fiber strand flaky or frizzy, are, indicating that the fusing of the fibers was imperfectly removed from the roving machine. If the same fiber strand in one A strand of cut fibers, which is treated in any temperature of 248 ° C, shows a Degrees. '' wrinkled surface and runaway fibers, which

From the examples given, it can be seen that the fiber strand was heated too much that, although according to the invention, predominantly strands Although the throughput speed of the fiber of fibers for the production of the filter elements vor- strand through the condenser tube is struck by a row which the fibers are essentially oriented in the longitudinal direction due to factors such as the composition of the fibers, the temperature of the tube, the thickness of the strand The structure of the product is dependent on the uniformity of the product, filter elements are lent to those skilled in the art, in which the fibers, however, are always in a position to be aligned with the most favorable leg to a lesser extent. The ultimate goal of finding conditions. It is important also to hinder od Wergstraeg. Like. May be in any rejected that satisfactory filter cylindrical or band-like shape is used in all respects 30 elements at the temperatures indicated above ans are often present in which such material is available. Mixtures of plasticized and non-plasticized AI's only requirement to be mentioned is that the
The strand must not be too bulky so that it can access the
desired diameter can be summarized
can. 35

The shaping step, of course, requires that
the cellulose ester fibers through the condenser tube
pulled under a certain tension and not
be pressed into the same. The union, and
in particular the melting of the fiber strand lying on the surface 4 ° in which a steam treatment is applied and with the surface, the method explained in relation to the embodiment according to the hot tube in contact with the fibers Fig. 3 is preferred. while the fibers stand under at least a portion of the steam up to the tensile stress inside the know. In general, fibers located as a fiber strand can penetrate. A steam treatment similar to any heatable tube can also be employed if desired, which has a funnel-shaped guide with the use of hot gases, such as hot ends and a mold surface at its other end, air, hot nitrogen, hot Has carbon dioxide. Embodiments in which the to etc. are combined. It is also possible to use a steam-converging part of the tube on an inner surface, which has solvents or softeners, through which the fiber strand slowly and all-in-one contains fumes. If the fibers are gradually gathered on these, they are preferred. Way to be heated as long as they are in a loose. The fiber strand will of course be fluffy or loose in the wide end, the earth funnel-shaped part of the condenser tube heating medium can be guided into the interior of the fiber bundle and so penetrate when passing through the narrower part of the that _r when the fiber bundle in the following tube is approximately open the desired cross section 55 pulled through a tube with a smaller diameter of the filter element compressed. It was found, is the union of the under the action of that the fiber strand, in general, to a slightly heat or the solvent softened fibers ia smaller cross-section, ^r as the desired filter a by corresponding W would correspond ahl the operating cross-section, together conditions in Wide limits of controllable strength must be made in order for the elastic springback of 60 and degrees to take place.

Fibers after the strand is released by the process changes noted above

Pressure exerted by the condenser tube atiszu- according to the invention hold all in common, daft they same. one that is related in its structure and

The condenser tube can in and of itself be on a uniform rod, which means that there are no longer any loose particles be heated in a loving way. For example, 65 has to deliver, and that from one of a marble there is a heat-enclosed fiber bundle flowing around the condenser tube. It showed exchange liquid, an infrared radiation or a heating element that those embodiments of a rod due to dielectric losses are particularly suitable where the jacket passes through will. For acetyl cellulose, such as those used to unite the yarn at or near the OberffäAe> Production is used, which is formed, for example, a 70 of the fiber bundle lying fibers. ■ ..!

macher-containing acetyl cellulose fibers at throughput speeds from 30 to 60 cm / min up to 1220 cm / min and more can be produced.

In cases where the surface of the fiber strand is exposed to a solvent mist or solvent vapors is exposed, the tube forming the fiber strand into the filter rod can be at room temperature being held. In certain cases,

Such a design can of course be used together with a further wrapping made of paper or the like , which is particularly appropriate if the association only partially or incoherent skin was formed.

The filter elements according to the invention can not only remove tars, nicotine or serve similar substances distilling from burning tobacco. The manufactured according to the invention Material is also, for example, for filtering air, e.g. B. in air cleaning systems, suitable.

The material can also be used to filter other gases or liquids.

The following examples serve to further illustrate the invention.

example 1

A fiber strand of continuous length made of plasticized cellulose ester fibers, as used in yarn manufacture Acetyl triethyl citrate is used as a pleasant-tasting, non-toxic plasticizer was fed in sufficient quantity through a circular shaped heating element Condenser tube. The temperature of the tube was kept at 225 ° C. The one from the condenser tube the compressed fiber strand running out was pulled at such a speed that that the fibers of the surface of the fiber strand in the condenser tube melted and adhered to each other and thus formed a thin, solid surface that holds the fiber strand together.

The mouth of the condenser tube had a diameter of about 8.4 mm. The educated Accordingly, the filter rod had just the right dimensions to be used in normal cigarettes Filter mouthpiece to be used. The density of one and the pressure drop in one piece of one The particular length of the filter rod depends essentially on the denier, the dimensions and the number depends on the plasticized fibers used. Depending on the material at hand, it is It is readily possible to choose these conditions in such a way that the properties are highly satisfactory of the filter elements can be achieved in terms of their density, their pressure drop and their filtering ability

can. _r,. . , _

Example 2

Usual non-plasticized acetyl cellulose staple fibers, how they are used to make yarn were made on a coating or carding machine with plasticized staple fibers containing 40% triacetin, in the ratio 70% not plasticized fibers mixed to 30% · plasticized fibers. The fibers were in the Brought the form of a drawn strand in which they were oriented substantially in the longitudinal direction and then through a cylinder heated to 250 ° C Condenser tube has been passed. In doing so, the fibers were pressed together and formed into a continuous, heat-sealed rod, which is cut into long pieces became. One of these parts was attached to the tobacco core of a cigarette and with it through a common paper wrapping connected. Finally the filter mouthpiece of the cigarette got through a cork sheet stuck over as a mouthpiece.

Example 3

According to one embodiment of the method according to the invention, a strand piece, its fibers were oriented essentially in the longitudinal direction and that made of 20% plasticized staple fibers and consisted of 80% non-plasticized staple fibers, through one consisting largely of glass Device drawn, as shown schematically in Fig. 3.

Air that had passed through a hot copper coil was supplied to that indicated in FIG Bodies initiated into the device and impacted in the enlarged, spherical portion of the device the piece of rope that was continuously drawn through the device. The strand piece, whose fibers were now softened by the action of the hot air, then ran through the with 38 designated, narrowed part of the device. As the fibers pass through part 35, they cool while or while continuing to run below their softening point, so that welding of the Fibers takes place in the fiber strand. By introducing the hot air under positive pressure and / or by application a negative pressure on the other side of the device, the hot air is constricted by the one on the Part of the device located section of the fiber bundle driven so that welding of the fibers occurs not only on the surface of the strand but also inside it. the However, the use of a vacuum pump is not absolutely necessary for this. By changing the Flow rate of the hot air and by changing the throughput speed of the fiber strand by means of the device, the degree of welding can be changed as desired. By choosing high flow speeds and high temperatures of the hot air and a lower one The throughput speed of the fiber bundle is essentially dependent on the welding effect Limited surface of the strand piece. By reducing the flow speed of the hot air a much lower degree of welding can be achieved, so that the end product rather soft and furry and not, as in the former case, highly elastic and smooth.

Example 4

Another device similar to that used in Example 3 was made. At this However, the device has considerably lengthened the spherical part into which the hot air is introduced and provided with two further inlet openings for hot air. The middle of the additionally arranged Hot air openings were in a perpendicular to the plane laid by the first pair Level. In this way, the length of the fiber strand exposed to the stream of hot air was increased and thus a better penetration of the hot air into the fiber strand. The use of four hot air ovens instead of two also ensures a more even distribution of the hot air on the fiber strand.

B e i s ρ ί e 1 5

A third, that used in Examples 3 and 4 Devices also similar device consisted of a copper pipe coil attached to its inner circumference was provided with a large number of bores, so that in this way one A plurality of outlet openings for the hot air guided in the copper pipe was formed. By A loose bundle of fibers or a strand of fibers was pulled from the copper pipe coil so that it was removed from the

Hot air was irradiated. In addition to the copper pipe coil a funnel made of glass was provided. It is of course possible at any time the funnel can also be made of metal or another material. The entire fiber strand ran from the copper coil into the funnel, in which it was compressed so that its fibers spread out united with each other. On the outside of the neck of the funnel was an electric heating coil

made and non-plasticized acetyl cellulose fibers jv has been processed. The fiber strand weighed 14.9 to 16.3 g / m and provided one Filter rod from 12.8 to 14.2 g / m. In order to achieve a winding 5 with a uniform weight, a Impact machine used with three clubs. The fiber strand continuously running out of the card was placed in a preheat tube that was 2.54 cm in diameter, extending across a

put on. The heat generated by this heating coil was 16 inches long to 1.59 inches in diameter

welds the fibers lying on the surface of the fiber bundle even further.

When the heating coil is switched off, i.e. the neck of the funnel is not heated, the through the shows

narrowed. The tube was heated to 220 ° C and served to preheat the fiber strand, which the further summarization of the fiber strand before it reaches the forming nozzle, facilitated. The pre

The hot air heating generated by the copper pipe snake also enables better control of the jets and the temperature of the fiber strand drawn through the funnel of the shaping nozzle. The preheated in this way ensures a relatively good weld of the fibers
at its core, however, a relatively weak one

Welding of the fibers on its surface.

Fiber strand, as already mentioned above, adjusted so as to increase or decrease to achieve the degree of welding of the fibers.

Example 6

A hede of continuous, crimped acetyl cellulose fibers or threads, but not containing any soft

The fiber strand was then put into a smooth surface initiated having molding nozzle. This shaping nozzle was made of brass and had a length of When the combed fiber strand rises under the same 20 22.9 cm, of which 15.25 cm is tapered. the Conditions, but with heating of the throat of the forming nozzle had a through funnel at its input end, is treated, a good diameter of 2.23 cm occurs, which is in the conical weld the fibers of the fiber strand across the 0.86 cm portion to the 7.62 cm long forming surface entire cross-section. decreased. The molding surface of the molding nozzle was

In the tests given above, the 25 most favorable around the shaping nozzle were made by means of immersion heaters Operating conditions of the various wraps were heated to 210 ° C. In the molding nozzle According to the physical properties devices, the preheated fiber strand turned into satisfactory The filter rod produced by the device is turned into a cylindrical rod in a determining manner and l> eurteilt and j * e after the heating, molded by the plasticized acetyl die Flow rate of the hot air stream 30 cellulose fibers on the surface of the fiber mass and the passage speed of the combed melted and so the surface part of the mass too

fused to a fiber skin or housing surrounding the inner fiber bundle.

It turns out that the diameter of the fiber rod produced in this way is between 8.15 mm and 8.40 mm, depending on the weight of the unprocessed fiber rod and the strength of the pull with which the filter rod is pulled out of the molding lies. After the molding process, the filter maker was added, and the rod shown in FIG. 1 was passed through a 2V2-inch tube in which it was treated. At higher temperatures, four compressed air nozzles under a pressure of temperatures resulted in a fusion of the fibers in 2.81 atm and was cooled. An immediately following notable measure, but it was also possible to prevent cooling from determining the degradation of the acetyl cellulose on the filter rod. However, when the applied tension reaches an inadmissible magnitude because it has softened the acetyl cellulose fibers, a solidification of the molten softener showed itself that easily reached fibers contained with this device. The pulling action required to pull through the usable filter rods according to the invention was able to be established. The use of fiber end of all process stages is generated by pulling drums arranged at the end of the head or a fiber hede instead of a combed direction. In the case of a fiber strand, the advantage of a larger preferred embodiment is the uniformity of tension and the avoidance of some working drums consisting of two grooved steps in the production of the raw material. Drive wheels or drive rollers attached belts. The -p,. · 1 7 continuously running out ^{of the device}

^Sp filter rod was then used at the end of the pull

A mixture was cut from acetyl cellulose cutting knives arranged in drums into pieces of staple fiber with a 2W staple length, as cut for the 66 mm length yarn used in conventional manufacture, the maximum crimp
and weighed 5 denier per fiber length, first
Component and a plasticized acetyl cellulose staple fiber with a fiber length of 2Va ", as they are also 60
if used for yarn production and the
also weighed 5 denier per fiber length and as
Plasticizer contained 50% acetyl triethyl citrate than
/ • -leitern component produced and with a

Mixture of 96% polyoxyethylene sorbitan mono- 65 arranged and formed a matted rod, laurate and 4% saccharine lubricated. The tuned its fibers on the surface of the same means Mixture was placed in a beater, connected to a solvent sprayer in which it was processed into a lap, which was and which encloses the inner fiber core formed by means of a card to form a clipped fiber housing. A number of this way strand made of a balanced mixture of soft filter elements was made with Filtejv

Cigarette making machines used to make filter tipped cigarettes became.

Example 8

A filter element made of fine, white acetyl cellulose fibers was made according to the above procedure manufactured. The fibers were longitudinal

elements of the known type are compared in order to determine the physical properties and the filter efficiency to determine the same. The results showed that the filter elements according to the invention improved Have effectiveness and nicotine, tars or the like. To a greater extent, without them would adversely affect the moisture content of the smoke passed through the filter.

The most favorable specific weight of the filter elements cannot be stated without further ado, since the large number of variables in the manufacture of the filter elements cover a relatively wide range the most favorable specific weights. If a mixture of plasticized and Non-plasticized acetyl cellulose fibers are used and the fibers are converted into rods by means of heat of the usual cigarette diameter are welded, filter elements turned out to be, of which 917 up to 1121 pieces with a length of 66 mm each weigh 1 kg, for filter mouthpieces of cigarettes with Cork mouth sheet most suitable.

Such filter elements can be easiest also with the usual cigarette manufacturing machines to process.

Claims (10)

Claims 1. Filter element for tobacco smoke, consisting of a rod-shaped fiber mass, in the synthetic Fibers or threads, in particular cellulose derivative threads, join together to form a self-supporting, coherent one and dimensionally stable, connected at least at intervals along the fibers or threads, optionally by a sheath wrapped bundles are united, characterized in that the fibers or threads by a Solvent and / or fused by heat. 2. Filter element according to claim 1, characterized in that the fibers or threads of the outer layer of the bundle are fused together essentially over their entire length, creating a coat. 3. Filter element according to claim 2, characterized in that the jacket with the adjacent to it Fibers or threads fused at intervals. 4. Filter element according to claim 1, characterized in that the bundle of a paper jacket or the like is wrapped. 5. Filter elements according to claims 1 to 4, characterized in that the bundle consists of one Mixture of acetyl cellulose threads consists of those that have been mixed with a plasticizer and those that do not contain a plasticizer, those with a plasticizer staggered threads due to the action of heat and / or a solvent among themselves and are fused with the threads not mixed with a plasticizer. 6. A method for producing filter elements according to claims 1 to S, in which a longer bundle or strand of substantially longitudinally oriented Acetyl cellulose fibers or threads are drawn through a conical forming nozzle, characterized in that that the fibers or threads are atomized in a solvent or a plasticizer before they pass through the conical shaping nozzle Form or in vapor form, so that the bundle or strand at Passage through the conical shaping nozzle, preferably with the application of heat, to one dimensionally stable rod fused to one another at least at intervals along their course Filaments or fibers is formed, which is then cut into filter elements of appropriate length will. 7. The method according to claims 1 to 6, characterized in that the shaping nozzle so far is heated that the lying on the surface of the fiber bundle fibers to form a closed Mantle merge. 8. The method according to claims 6 and 7, characterized in that acetyl cellulose threads with an acetyl value of 38.9 to 39.2% can be used. 9. The method according to claims 6 to 8, characterized in that an acetyl cellulose fiber strand, as it is usually used for yarn production, is used. 10. Filter element according to claim 9, characterized by the use of continuous curled threads. Considered publications: German Patent No. 186,929; British Patent Nos. 419 629, 665 278. 1 sheet of drawings © 809 507/85 4.58