EP3453266A1 - Tabacco sheet, rod-shaped smoking article and method for producing a tabacco sheet - Google Patents

Abstract

The invention relates to a tobacco foil (2), a rod-shaped smoking article (8) and a method for producing a tobacco foil (2). The tobacco sheet (2) of reconstituted tobacco comprises between 50% and 70% ground tobacco stems and between 10% and 20% tobacco dust. The tobacco sheet (2) comprises between 20% and 30% cellulose fibers and is produced in a paper process.

Description

The invention relates to a tobacco sheet of reconstituted tobacco which comprises between 50% and 70% ground tobacco ribs and between 10% and 20% tobacco dust. Furthermore, the invention relates to a rod-shaped smoking article comprising such a tobacco sheet. The invention also relates to a method of producing tobacco sheet from reconstituted tobacco comprising between 50% and 70% ground tobacco ribs and between 10% and 20% tobacco dust.

Much of the material cost of rod-shaped smoking articles, such as cigarettes, is determined by their proportion of tobacco. Therefore, the saving of tobacco material with regard to a possible cost savings gains more and more importance. For this purpose, various measures are known. One possibility is to produce the rod-shaped smoking article as a so-called double-wrap article with reduced tobacco content. The outer diameter of such a smoking article is unchanged compared to conventional smoking articles, while the effective diameter of the tobacco rod is reduced.

From the EP 0 160 380 A1 For example, a cigarette is known that has a tobacco rod of reduced diameter. This is surrounded by a sandwich casing, which consists of a directly resting on the tobacco rod, smooth inner shell and a likewise smooth outer shell and arranged between the inner and the outer shell longitudinally coined intermediate sheath. The wrappings may be made of tobacco foil.

In order for such a smoking article to have the desired mechanical properties, for example, sufficiently stable and, moreover, to reduce the diameter of the tobacco rod efficiently, the tobacco foil inserted as an intermediate wrap or liner is provided with a three-dimensional structure. For example, it is crimped so that it has parallel longitudinal grooves. In this processing of the tobacco sheet, the embossing or crimping, however, there are always undesirable breaks in the tobacco sheet.

It is an object of the invention to provide an improved tobacco sheet of reconstituted tobacco, an improved rod-shaped article comprising such a tobacco sheet, and an improved method for producing tobacco sheet from reconstituted tobacco.

The object is achieved by a tobacco sheet of reconstituted tobacco which comprises between 50% and 70% ground tobacco ribs and between 10% and 20% tobacco dust, this tobacco sheet being formed by the tobacco sheet comprising between 20% and 30% cellulose fibers have a fiber orientation direction.

Advantageously, such a tobacco sheet can be processed well, whereby, in particular, the probability of damage or even breakage of the film, for example during crimping, that is to say the introduction of a three-dimensional structure into the tobacco sheet, is reduced to a minimum is. Furthermore, the film receives the embossed or crimped structure very well and is very tear-resistant. This improved processability and increased tear resistance is due, among other things, to the existing fiber orientation.

According to one embodiment, it is provided that the ground tobacco ribs are obtainable by a high-consistency fibrillating grinding, in particular at a substance density of greater than 15%. Furthermore, the short fiber content of the cellulose fibers is in particular at a maximum of 30%.

The tobacco ribs are ground fibrillating, i. with as far as possible preservation of the fiber length "frayed". For this purpose, for example, a Refinermahlung comes into consideration. When grinding the tobacco ribs in the refiner special attention can be paid to the preservation of the long fibers. Due to the addition of low proportion of short fibers, a high long fiber content is achieved in the material of the tobacco sheet. This has an advantageous effect on the mechanical properties of the tobacco sheet, so that it shows an extremely low tendency to break during crimping.

The limited short fiber content can be achieved, for example, by admixing short fiber pulps. Pulp of birch, beech, poplar or eucalyptus, for example, is suitable for this purpose. According to a further advantageous embodiment, it is provided that the cellulose fibers are obtained from softwood pulp and / or from pulp of annual plants. Cellulosic fibers having a high fiber length can be obtained, for example, from European or Canadian pine or spruce which provide a softwood pulp. The pulp of annual plants is obtained, for example, from flax, hemp, sisal or bagasse.

According to a further advantageous embodiment, it is provided that a material thickness of the tobacco foil is between 250 μm and 400 μm. This value has also proved to be advantageous, for example with regard to the preservation of the embossed structure, the tear strength and the further processing of the film.

It is further provided in particular that the tobacco sheet has a tensile strength which is greater than 20 N, based on an elongated test strip consisting of the tobacco foil with a width transverse to a tensile direction of 15 mm and a material thickness of between 250 μm and 400 μm. In particular, it is provided that the tear strength is determined on test strips having a material thickness of between 300 μm and 363 μm.

A three-dimensional structure can be impressed or crimped efficiently and sustainably in a tobacco foil of the stated material thickness and with the aforementioned tear resistance. At the same time, the likelihood of the tobacco foil breaking during this process is reduced to an absolute minimum.

According to a further advantageous embodiment, the tobacco foil has a three-dimensional structure consisting of alternately adjacent elongate elevations and depressions, wherein the elevations and depressions extend in a structure longitudinal direction, and wherein a fiber preform direction of the cellulose fibers is oriented transversely to the structure longitudinal direction.

The fact that these two directions are oriented transversely to each other, the cellulose fibers contained are bent along their longitudinal direction during crimping. Such a structure shows a reduced tendency to breakage, the film can be processed better and is more tear-resistant.

In particular, it is provided that the fiber biasing direction and the structure longitudinal direction include an angle which is between 45 ° and 90 °. Such an angle has been found in practice to be particularly advantageous.

The introduced into the tobacco sheet three-dimensional structure of the alternately adjacent elongated elevation and depressions has a structure longitudinal direction. This structural longitudinal direction is oriented parallel to a longitudinal extension direction of the adjacent elevations and depressions.

Furthermore, it is provided in particular that the tobacco foil is produced in a paper process.

A so-called slurry process, which is likewise often used to produce tobacco sheets, is not used. Both the paper process and the slurry process are in " Tobacco Encyclopedia ", Ernst Voges, 1984, publisher TJI, in Part II in the" Sheet Tobacco "chapter, beginning on page 389 , described in detail. In the widespread paper process, a mixture of tobacco dust, ribs and other components such as partially whole leaves is first crushed and extracted in water. This extract is then concentrated by evaporation, for example, and retained for later use. The insoluble residue is further softened so that the resulting fibrous material can be made into a paper-like material in a modified papermaking machine. This endless material is then dried and re-treated to the desired extent with the previously concentrated extract, so that the desired taste can be adjusted. The resulting impregnated material is dried before being sent for further processing. In contrast, in the slurry process, the dry tobacco materials are finely divided and usually mixed with a small amount of binder. The resulting mass is poured onto an endless metal strip on which it is dried.

The tobacco sheet according to an advantageous embodiment comprises 60% ground tobacco ribs, 15% tobacco dust and 25% cellulose fibers.

For further processing, the tobacco sheet is brought, for example, to a moisture content of between 12% and 14%. This can be done by storage in an appropriate atmosphere. If the tobacco film has the desired moisture content, it is packaged airtight for transport, for example, wrapped in cling film.

It is further provided, for example, that the tobacco foil is rolled up on a reel. This has for example a usual for the production of kingsize cigarettes width of 24mm. Furthermore, it is particularly provided that the tobacco sheet has a tensile strength of 6% to 10%, wherein the elongation is considered to break or crack. In particular, the tobacco foil has a basis weight which is between 80 g / m ² and 130 g / m ² .

The object is further achieved by a rod-shaped smoking article comprising a tobacco sheet according to one or more of the aforementioned embodiments, wherein the tobacco sheet on an inner side surrounds a tobacco rod, and wherein the structure longitudinal direction is oriented at least approximately in the direction of a longitudinal axial direction of the smoking article, and on an outer side is surrounded by a wrapping paper, wherein the elevations and depressions of the tobacco sheet in longitudinal axial direction formed channels between the tobacco sheet and the wrapping paper.

Advantageously, the proportion of tobacco can be reduced in such a rod-shaped article, whereby this is more economical to produce. The quality of the rod-shaped smoking article is improved by the use of the tobacco sheet according to aspects of the invention over conventional rod-shaped articles, since the tobacco sheet used exhibits a much lower tendency to break when producing its three-dimensional structure. Incidentally, the rod-shaped smoking article has the same or similar advantages as already mentioned with regard to the tobacco foil.

It is preferably provided that a ratio between a width of the tobacco foil and a width of a wrapping paper of the rod-shaped smoking article is between 1.05 and 1.2. This size ratio between tobacco foil and wrapping paper is useful for making various types of smoking articles such as kingsize cigarettes, slim cigarettes or super slim cigarettes. It has proven to be particularly advantageous in practice.

The object is further achieved by a method for producing a tobacco sheet from reconstituted tobacco, which comprises between 50% and 70% ground tobacco ribs and between 10% and 20% tobacco dust, this method being further developed by producing the tobacco sheet in addition to the ground tobacco ribs and the tobacco dust is used between 20% and 30% cellulosic fibers, and the cellulosic fibers are given a fiber orientation in manufacture.

The preparation of the tobacco sheet is carried out in particular in a paper process. The three-dimensional structure is produced, for example, in a crimping process or in an embossing process. The grinding of the tobacco ribs takes place for example in a refiner. The grinding of the tobacco ribs is a wet process, there is no dry grinding.

With the aid of such a method, it is possible with advantage to produce a tobacco foil which, when producing a three-dimensional structure, for example during crimping, tends to be damaged less than conventional films. This of course applies when a conventional film and a film according to an embodiment of the same thickness are compared. Thus, the method can be used to produce a film which, for the same thickness, exhibits the substantially improved resistance to the mechanical influence of the crimping process.

In particular, the method is developed in that the three-dimensional structure is produced such that the fiber orientation direction and the structural longitudinal direction include an angle that is between 45 ° and 90 °.

Furthermore, it is provided in particular that the tobacco ribs are ground in a fibrillating manner in a refiner, wherein a high consistency grinding, in particular at a consistency greater than 15%, is made, and / or a cutting angle between blades of the sets used in the refiner between 15 ° and 60 ° and / or a freeness of the ground tobacco ribs 30 to 35 SR (Schopper-Riegler) is. The mentioned parameters have proven to be particularly advantageous for the production of a well-processed, stable and resistant tobacco foil.

According to a further advantageous embodiment, it is provided that cellulose fibers are used which are obtained from softwood pulp and / or from pulp of annual plants. The softwood pulp is obtained, for example, from European or Canadian pine or spruce. The pulp of annual plants is obtained, for example, from flax, hemp, sisal or bagasse.

The cellulose fibers used furthermore preferably have a short fiber content of not more than 30%. This short fiber content is obtained, for example, from birch, beech, poplar or eucalyptus. Too high a short fiber content would reduce the strength of the tobacco sheet too much, which is why said limit has been found to be advantageous in practice.

It is further provided in particular that the tobacco sheet is produced with a material thickness between 250 microns and 400 microns.

According to a further advantageous embodiment, it is provided that the tobacco sheet is given a three-dimensional structure of alternately adjacent elongated elevations and depressions wherein the ridges and valleys extend in a structural longitudinal direction and wherein the three-dimensional structure is made such that a fiber biasing direction of the cellulose fibers is oriented transversely to the structural longitudinal direction. Furthermore, it is provided in particular that the three-dimensional structure is produced in such a way that the fiber preferential direction and the structure longitudinal direction enclose an angle which is between 45 ° and 90 °.

Incidentally, the same or similar advantages as already mentioned with respect to the tobacco sheet itself apply to the method for producing the tobacco sheet.

Further features of the invention will become apparent from the description of embodiments according to the invention together with the claims and the accompanying drawings. Embodiments of the invention may satisfy individual features or a combination of several features.

Fig. 1 und 2

jeweils eine schematisch vereinfachte Darstellung einer Tabakfolie in angedeutet perspektivischer Draufsicht,

Fig. 3

eine schematisch vereinfachte Seitenansicht eines stabförmigen Rauchartikels und

Fig. 4

einen schematisch vereinfachten Querschnitt durch einen solchen Rauchartikel entlang der Ebene IV - IV.

The invention will be described below without limiting the general inventive idea by means of embodiments with reference to the drawings, reference being expressly made to the drawings with respect to all in the text unspecified details of the invention. Show it:

Fig. 1 and 2

in each case a schematically simplified representation of a tobacco sheet in an indicated perspective plan view,

Fig. 3

a simplified schematic side view of a rod-shaped smoking article and

Fig. 4

a schematically simplified cross section through such a smoking article along the plane IV - IV.

In the drawings, the same or similar elements and / or parts provided with the same reference numerals, so that is apart from a new idea each case.

Fig. 1 and 2 show schematically and simplifies a tobacco sheet 2 of reconstituted tobacco. The tobacco sheet 2 comprises between 50% and 70% ground tobacco stems. The tobacco ribs are preferably treated in a high consistency milling, wherein in this process, the consistency is set for example to greater than 15%. The grinding takes place fibrillating, ie "fraying", with as much as possible preservation of the long fiber content. The high consistency range in which the refiner takes place is of a mid-consistency range typically between 8% and 15% stock and a low consistency range typically below 8% stock. The preparation of the tobacco ribs is procedurally with the aim of creating new surfaces and to increase the strength of the films produced therefrom. Special attention is paid to the preservation of the long fibers. The grinding of the tobacco ribs is done in a wet process, there is no dry grinding.

The tobacco sheet 2 also comprises between 10% and 20% tobacco dust. The tobacco dust is suspended or added after grinding. Too high a proportion of tobacco dust would reduce the strength of the tobacco sheet 2, which is why its proportion remains limited to values in the interval mentioned.

Furthermore, the tobacco sheet 2 comprises between 20% and 30% cellulose fibers. The cellulose fibers have a fiber orientation direction. In particular, it is envisaged that the tobacco sheet comprises 60% ground tobacco ribs, 15% tobacco dust and 25% cellulose fibers.

According to a further embodiment, the tobacco sheet 2 further comprises a three-dimensional structure of alternately adjacent elongated elevations and depressions. This three-dimensional Structure, more precisely a longitudinal extent of the elevations and depressions, is / are in Fig. 1 and 2 indicated by parallel lines. They define a structural longitudinal direction 4, which extends in the direction of the solid lines shown only in sections. The structure longitudinal direction 4 is thus parallel to a longitudinal direction of the elevations and depressions.

The tobacco sheet 2 comprises between 20% and 30% cellulose fibers which have an in Fig. 1 and 2 having fiber-preferred direction 6 indicated by dashed lines. The tobacco sheet 2 is produced in a paper process. In this process, the cellulosic fibers are oriented in the fiber orientation direction 6 by making use of a speed difference in the flow of material between the jet and the wire during production in the paper machine. Due to this speed difference, ie, a forward or lagging of the screen, the fibers are oriented more or less strongly in the machine direction. The fiber orientation direction 6 thus denotes a preferred orientation of the cellulose fibers, wherein, of course, the orientations of individual fibers deviate more or less from this fiber orientation direction.

At the in Fig. 1 illustrated embodiment, the fiber prefeeding 6 is oriented parallel to the longitudinal direction of the schematically indicated path of the tobacco sheet 2. In Fig. 2 the opposite situation is shown. In the case of the tobacco sheet 2 shown schematically and simplified there, the fiber prefraction direction 6 indicated by a dashed line is oriented transversely to a longitudinal direction of the illustrated web, while the structure longitudinal direction 4 extends parallel to this longitudinal direction.

It is important that the fiber orientation direction 6 of the cellulose fibers and the structure longitudinal direction 4 of the three-dimensional structure are oriented transversely to one another. An angle α between the fiber biasing direction 6 and the structural longitudinal direction 4 is preferably between 45 ° and 90 °. In the illustrated embodiments, the angle α is at least approximately 90 ° by way of example.

The cellulose fibers used are obtained, for example, from softwood pulp, such as European or Canadian pine or spruce. Alternatively or additionally, pulp from annual plants may also be used, such as, for example, flax, hemp, sisal or bagasse. A short fiber content of the cellulose fibers is preferably below 30%. The short fiber content is obtained, for example, from short fiber pulps of, for example, birch, beech, poplar or eucalyptus.

A thickness of the tobacco sheet 2 is for example between 250 microns and 400 microns. Further, the tobacco sheet 2 has a tensile strength which is greater than 20 N, which is considered to be an elongated test strip with a width transverse to a tensile direction of 15 mm and a material thickness of between 250 μm and 400 μm cut out of the tobacco foil 2. The said tensile strength also relates in particular to a situation in which the tensile force is applied at least approximately parallel to the fiber preferential direction 6.

Essential for the crimping result, ie the quality of the three-dimensional structure, which is introduced into the tobacco sheet 2, is the orientation of the fiber preferential direction 6 to the structure longitudinal direction 4, which is introduced in the crimping process. The crimping takes place in such a way that the structure longitudinal direction 4 lies transversely to the fiber preferential direction 6. Thus, it can be achieved that a probability of the formation of cracks, fractures or other damage to the material during the crimping process is substantially reduced.

The tobacco sheet 2 has, for example, a basis weight which is between 80 g / m ² and 130 g / m ² . The cellulose used for the production of the tobacco sheet 2 is ground, for example, in a refiner, namely at a freeness in the range between 30 SR and 35 SR, where the abbreviation SR stands for the known unit of the degree of grinding Schopper-Riegler. The sets used in the refiner are for example adjusted so that between the knives of the cooperating sets an angle of 15 ° to 60 ° is set.

With the help of the tobacco foil 2, rod-shaped smoking articles can preferably be produced. Such is exemplified in a schematically simplified side view Fig. 3 shown. The rod-shaped smoking article 8 comprises a tobacco foil 2 as described above. At one end of the rod-shaped smoking article 8 is a filter plug 10, opposite the fire end. A tobacco rod is enclosed by a wrapping paper 12, which adjoins the filter plug 10.

At the in Fig. 3 As shown by way of example the smoking article 8, the tobacco foil 2, as indicated by the extent of the longitudinal direction 4 of the structure in the longitudinal axial direction L, does not reach the filter stopper 10 directly, for example only. The ratio of a width of the tobacco sheet 2 and a width of the wrapping paper 12 used, which reaches up to the filter plug 10 and slightly overlaps it, is in the range between 1.05 and 1.2.

Fig. 4 shows a schematically simplified cross section through the smoking article 8 in an area outside the filter plug 10, for example in the direction indicated by dashed line level IV-IV. In the center of the smoking article 8 is the tobacco rod 14, which is surrounded directly by the tobacco sheet 2. The tobacco sheet 2 comprises elongated elevations 16, which are in direct contact with the wrapping paper 12 and alternate with elongated depressions 18. The elevations 16 and recesses 18 extend in a structural longitudinal direction 4, which in Fig. 3 indicated by parallel lines. This structural longitudinal direction 4 is preferably parallel to a longitudinal direction L of the smoking article 8. As a result of the three-dimensional structure formed in the longitudinal direction L of the smoking article 8 oriented channels 20 between the tobacco sheet 2 and the wrapping paper 12. Compared to conventional smoking products by this measure, the volume of the tobacco rod 14 is reduced, which is why Smoking article 8 can be produced more economically.

All mentioned features, including the drawings alone to be taken as well as individual features that are disclosed in combination with other features are considered alone and in combination as essential to the invention. Embodiments of the invention may be accomplished by individual features or a combination of several features. In the context of the invention, features which are identified by "particular" or "preferably" are to be understood as optional features.

LIST OF REFERENCE NUMBERS

2

tobacco sheet

4

Structure longitudinally

6

Fiber preferred direction

8th

A smoking article

10

filter plug

12

wrapping paper

14

tobacco rod

16

increase

18

deepening

20

channels

α

corner

L

longitudinal axial

Claims (15)

A tobacco sheet (2) of reconstituted tobacco comprising between 50% and 70% ground tobacco ribs and between 10% and 20% tobacco dust, characterized in that the tobacco sheet (2) comprises between 20% and 30% cellulose fibers having a fiber orientation direction. Tobacco film (2) according to claim 1, characterized in that the ground tobacco ribs by a fibrillierende Hochkonsistenzmahlung, in particular at a consistency greater than 15%, are available. Tobacco film (2) according to claim 1 or 2, characterized in that the cellulose fibers are obtained from softwood pulp and / or from pulp of annual plants. Tobacco film (2) according to one of claims 1 to 3, characterized in that the cellulose fibers have a short fiber content of not more than 30%. Tobacco film (2) according to one of claims 1 to 4, characterized in that a thickness of the tobacco sheet (2) is between 250 microns and 400 microns. Tobacco film (2) according to one of claims 1 to 5, characterized in that the tobacco sheet (2) has a tensile strength which is greater than 20 N, based on a consisting of the tobacco sheet (2) elongated test strip with a width transverse to one Pull direction of 15 mm and a material thickness between 250 microns and 400 microns. Tobacco foil (2) according to one of claims 1 to 6, characterized in that the tobacco foil (2) has a three-dimensional structure of alternately juxtaposed elongated elevations (16) and depressions (18), wherein the elevations (16) and depressions ( 18) in a structural longitudinal direction (4), wherein a fiber prefraction direction (6) of the cellulose fibers is oriented transversely to the structure longitudinal direction (4), wherein in particular the fiber preforming direction (6) and the structural longitudinal direction (4) enclose an angle (α) between 45 ° and 90 °. Tobacco foil (2) according to one of claims 1 to 7, characterized in that the tobacco foil (2) is produced in a paper process. A rod-shaped smoking article (8) comprising a tobacco sheet (2) according to claim 7 or 8, which surrounds a tobacco rod (14) on an inner side, the structural longitudinal direction (4) being oriented at least approximately in the direction of a longitudinal axial direction (L) of the smoking article (8) is surrounded by a wrapping paper (12) on an outer side, wherein the elevations (16) and depressions (18) of the tobacco sheet (2) are channels oriented in the longitudinal axial direction (L) (20) form between the tobacco sheet (2) and the wrapping paper (12). A method of manufacturing a tobacco sheet (2) of reconstituted tobacco comprising between 50% and 70% ground tobacco ribs and between 10% and 20% tobacco dust, characterized in that in manufacturing the tobacco sheet (2) in addition to the ground tobacco ribs and tobacco dust 20% and 30% cellulose fibers are used and the cellulose fibers in manufacturing a fiber orientation direction (6) is given, wherein the tobacco sheet (2) is produced in particular in a paper process. A method according to claim 10, characterized in that the tobacco ribs are ground fibrillating in a refiner, wherein a Hochkonsistenzmahlung, in particular at a consistency greater than 15%, is made, and / or a cutting angle between knives of the sets used in the refiner between 15 ° and 60 ° and / or a freeness of the ground tobacco ribs is 30 to 35 SR (Schopper-Riegler). A method according to claim 10 or 11, characterized in that the cellulose fibers are used which are obtained from softwood pulp and / or from pulp of annual plants. Method according to one of claims 10 to 12, characterized in that cellulose fibers are used with a short fiber content of not more than 30%. Method according to one of claims 10 to 13, characterized in that the tobacco sheet (2) is produced with a material thickness between 250 microns and 400 microns. Method according to one of claims 10 to 14, characterized in that the tobacco sheet (2) has a three-dimensional structure alternately juxtaposed elongated ridges (16) and recesses (18), said ridges (16) and recesses (18) extending in a structural longitudinal direction (4), and wherein said three-dimensional structure is made such that a fiber biasing direction (6) of the cellulose fibers is oriented transversely to the structure longitudinal direction (4), wherein in particular the three-dimensional structure is produced such that the fiber biasing direction (6) and the structural longitudinal direction (4) enclose an angle (α) which is between 45 ° and 90 °.

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