WO2000033675A1

WO2000033675A1 - Cigarette paper tubes and method for making same

Info

Publication number: WO2000033675A1
Application number: PCT/BE1999/000162
Authority: WO
Inventors: Clément Victor Joseph CLAESEN
Original assignee: Rizla International B.V.
Priority date: 1998-12-09
Filing date: 1999-12-08
Publication date: 2000-06-15
Also published as: BE1012329A3; EP1054604A1; CA2320345A1; AU1540300A

Abstract

The invention concerns a cigarette paper (2) tube (1) comprising at least a filter element (3) housed in the tube at one first end thereof and peripherally permeable to air, an empty section (6) for receiving tobacco, located in the tube between the filter element and a second end of the tube, axially opposite to the first, and an insert to be placed in the mouth (7), formed by a tape (8) made of porous material and enclosing the tube at its first end over a distance sufficient to cover at least said filter element, the cigarette paper tube including at least an air permeable ventilating zone located so as to cover at least part of said filter element and produced on the cigarette paper (2, 12) before the tube (1, 19) is formed.

Description

"Cigarette paper tubes and their manufacturing process"

The present invention relates to a cigarette paper tube comprising,

- at least one filter element housed in the tube at a first end thereof and peripherally permeable to air,

- an empty tobacco receiving compartment, located in the tube between the filter element and a second end of the tube, axially opposite the first, this compartment being to be filled with tobacco by a user to make a cigarette, and - a socket to be placed in the mouth, formed of a ribbon of porous material and enveloping the tube at its first end over a distance sufficient to cover at least said at least one filtering element,

- the cigarette paper tube having at least one air permeable zone.

Prefabricated cigarette paper tubes which are to be filled with tobacco by the user have already been known on the market for a long time. Tobacco can be used in loose form and it is then packed inside the tube or it is in the form of a rod or carrot of tobacco perfectly suited to be pressed inside the cigarette paper tube. Such tubes provided at one end with a "filter tip" are also available on the market.

There is currently a general trend to smoke lighter cigarettes which are less harmful to health. One of the ways to make lighter cigarettes is to ventilate the cigarettes. The ventilation of filter-tipped cigarettes can be obtained by making the part of the cigarette that surrounds the filter element breathable.

In factory filter-tipped cigarettes two methods are currently used to break them down: a. An air permeable sleeve is used which surrounds the filter end itself enclosed in a very porous envelope (see for example GB-A-2264038). b. The socket to be placed in the mouth is punctured in the cigarette-making machine, after the cigarette has been fitted (see for example DE-

A-19530216).

It should however be noted that a cigarette with a factory filter tip has a specific structure: the tobacco rod wrapped in cigarette paper is mounted against a cylindrical filter element and the whole is held together by a so-called "mouthpiece" socket. . It suffices to provide a socket made of a very porous or perforated material before or during manufacture to obtain ventilation of the filter element.

Laser perforation, as provided in DE-A-19530216, is a complex operation requiring sophisticated and expensive equipment.

The paper cigarette tubes intended for the manufacture of cigarettes by the user himself have a fundamentally different structure from that of factory cigarettes. Since there is no tobacco to be applied during the manufacturing process, an empty compartment for receiving the tobacco must be made by wrapping a strip of cigarette paper around the filter elements.

In longitudinal section, a tube of cigarette paper with filter tip comprises on the mouth side: at. The absorbent fibrous material of the filter element. b. The envelope of the fibrous material which is preferably very porous. vs. Cigarette paper that is waterproof or not very breathable. d. The socket to be placed in the mouth which may be formed of a porous material and which envelops the tube over a sufficient distance to cover the filter element and preferably exceed it.

To allow ventilation of the filter end it is therefore necessary that the air can pass through the three layers b, c and d to reach the material a. The air permeability of layers b and d is therefore neutralized here by the cigarette paper, because using too porous cigarette paper would make the cigarette smokable since there would then be air penetration over the entire length of cigarette.

We therefore sought to solve the problem of ventilation in the filter ends of cigarette paper tubes and various proposals have already been made.

For example, cigarette paper tubes are known as described at the start (see EP-A-0615699). The cigarette paper tubes according to this patent application contain two filter elements spaced from each other. Perforations opening into the space between the two filter elements can be provided and they pass in one piece with the socket to be placed in the mouth and the cigarette paper. It is not explained in this document how these perforations are carried out, but it appears from the drawings that these are made after the manufacture of the tube, which poses problems of mechanical resistance of the tubes in the case of a perforation by mechanical means or cost problems in the case of the application of laser equipment, as mentioned above.

In EP-A-0689776, it has been proposed to produce a cigarette paper tube containing a first filter element at one of its ends and having against this first filter element a second filter element located outside the tube, but connected to the latter by a socket to be placed in the mouth which covers the two filter elements. The material of the socket to be placed in the mouth can be very porous or perforated in its part where it covers the second filter element. As there is no interposed cigarette paper at this level, ventilation may occur, ventilation which is not possible at the level of the first filter element. This arrangement nevertheless requires the use of two filters of different cross sections and a method of assembling the different parts which is relatively complex.

There are also known cigarette paper tubes with filter tips, the cigarette paper of which is provided with rows of perforations arranged longitudinally on the part of the tube forming the tobacco receiving compartment (DE-C-4107026). In this compartment can be inserted a tobacco cartridge wrapped in cigarette paper also provided with rows of longitudinal perforations. After sinking the tobacco cartridge into the tube, the user can, if he wishes to obtain a ventilation of his cigarette, rotate the cartridge around its axis to make the perforations of the cartridge coincide with those of the tube. This embodiment therefore does not relate to direct ventilation of the filter tip. The perforations on the part of the tube forming the hollow tobacco receiving compartment mechanically weaken this part and nothing is explained about the embodiment of the perforations. The present invention aims to develop cigarette paper tubes as described at the beginning, having a simple structure, which allows ventilation of the filter end of the tube. These tubes must be capable of being manufactured at high speed, at speeds of, for example, 6,000 tubes per minute or more, without incurring an indefensible additional cost. This problem is solved according to the invention by a cigarette paper tube as described at the start, this tube being characterized by the fact that it comprises at least one air permeable ventilation zone which is located so as to cover at least part of said at least one filter element and which is produced on cigarette paper before forming the tube. These tubes have the advantage of retaining an unmodified structure of non-ventilated filter-tip cigarette paper tubes, and of introducing ventilation therein. Perforations on already constructed tubes are not necessary, and various arrangements of several different filter elements inside the tube are not absolutely required. In addition, the air permeable ventilation zone which necessarily has a lower mechanical resistance than the other zones of the cigarette paper tube is completely or at least partially enclosed between, on the one hand, the filter element and, on the other hand, the socket to put in the mouth, which compensates for the local loss of mechanical strength of the cigarette paper.

According to one embodiment of the invention, the ventilation zone consists of pre-cut openings in the cigarette paper, which are completely interposed between, on the one hand, the filter element which is peripherally breathable and, d on the other hand, the ribbon of porous material of the sleeve. In this case, fairly wide openings can be provided in the cigarette paper, for example circular, oval, elongated, polygonal or other openings. One can in particular provide circular cutouts with a diameter of the order of 1 mm to 5 mm, preferably from 3 to 4 mm.

It is known to use cigarette paper having cutouts of this order of magnitude in the manufacture of cigarettes which one wishes to make smokable. The openings are located at the level of the tobacco rod and they are of a size such that the supply of air into the tobacco is too large to allow these cigarettes to be smoked. The user must then plug these openings to be able to smoke these cigarettes (see WO-98/07338). It is of course impossible to design cigarette paper tubes carrying such openings at the level of the compartment intended to receive tobacco, without mechanically weakening unbearably these tubes.

According to another embodiment of the invention, the ventilation zone comprises peripheral openings precut in the cigarette paper which, on a part of their surface, are interposed between, on the one hand, the filter element which is peripherally permeable to the air and, on the other hand, the ribbon of porous material of the sleeve and which, on another part of their surface, overflow into the empty tobacco receiving compartment. Such tubes offer the advantage of simultaneously ventilating the filter element and the tobacco introduced into the tobacco receiving compartment, by providing an appropriate dilution of the inspired smoke and also reducing in the smoke the tar, nicotine and monoxide content. of carbon.

According to an advantageous embodiment of the invention, the sleeve to be placed in the mouth is made of a ribbon of porous material which has a predetermined air permeability and comprises at least one zone of higher permeability, which is located so as to cover at least partially said at least one ventilation zone of the cigarette paper tube and with which the ribbon of material is provided before winding the sleeve around the tube. In this exemplary embodiment, the socket to be placed in the mouth may be formed of a material which is not very breathable with the exception of at least one zone and therefore be mechanically resistant, while allowing air to pass through. through the cigarette paper ventilation area. When the latter is formed by large openings, the tolerances are advantageously large for the arrangement of the permeability zone. from the socket. The superposition of the two ventilation and permeability zones regulates the ventilation rate to be obtained.

According to a preferred embodiment of the invention, said at least one upper permeability zone comprises perforations in the strip of porous material. These perforations can be microperforations quite common for those skilled in the art in the field of cigarette ventilation.

The present invention also relates to a method of manufacturing cigarette paper tubes comprising - unwinding a ribbon of cigarette paper,

an application of at least one cylindrical filter element that is peripherally permeable to air on said tape,

a wrapping of said at least one filter element by the tape so as to form a cigarette paper tube, a sectioning of the cigarette paper tube provided with said at least one filter element, and

- A winding of a ribbon of porous material around said tube so as to form a sleeve covering at least said at least one filter element. The present invention aims to develop a manufacturing process allowing the use of the known apparatus for manufacturing such cigarette paper tubes, without having to add expensive device in the manufacturing line. The method must allow the manufacture of the cigarette paper tube, the filter end of which is directly ventilated at its periphery and the mechanical stability of which has not been unbearably reduced for manufacture or transport.

This problem has been resolved by a method as described above which further comprises shaping the strip of cigarette paper before forming the tube so that it has at least one air permeable ventilation zone which, after said wrap, is located so as to cover at least a part of said at least one filter element. This shaping may include a displacement of the strip of cigarette paper in a longitudinal direction and a cutting of openings arranged substantially transversely to this direction, at regular distances. This is advantageously carried out in a completely usual manner, for example by a rotary perforation mechanism or by holes of the punch type using punches (see for example GB-A-2264038 cited above ), on the transport line of the cigarette paper tape, after unwinding from a reel.

According to one embodiment of the invention, the ribbon of porous material of the sleeve to be placed in the mouth has a predetermined air permeability and the method comprises shaping the ribbon of porous material before said winding so that it has at least one upper permeability zone which, after winding, at least partially covers said at least one tube ventilation zone. The shaping of the ribbon of porous material can comprise a displacement of the ribbon of porous material in a longitudinal direction and a perforation in the longitudinal direction of rows of perforations arranged parallel to this direction.

Embodiments of the cigarette paper tubes according to the invention are indicated in claims 1 to 10.

Embodiments of the method according to the invention are indicated in claims 11 to 18. Other details and particularities of the invention will emerge from the description given below, without limitation and with reference to the accompanying drawings.

Figure 1 shows a perspective view of a cigarette paper tube according to the invention, partially disassembled. FIG. 2 schematically represents a device for manufacturing tubes according to the invention.

Figure 3 shows an alternative embodiment of the tube according to the invention. Figure 1 illustrates a partially disassembled cigarette paper tube 2. The tube 1 comprises a filter element 3, which in the illustrated case is in the usual way made up of a core of absorbent material 4, for example of fibers, which is surrounded by an envelope 5 of breathable material . This filter element 3 is housed in the tube at a first end thereof. It should be understood that the tube may contain several filter elements which succeed one another side by side or which are spaced from one another.

When the cigarette paper 2 is completely wrapped around the filter element 3, it forms in the part which is not filled by the filter element a tobacco receiving compartment 6 which is empty and which is to be filled with a way known by tobacco to make a cigarette. This compartment can be filled with tobacco in loose form or in the form of a preformed tobacco rod or carrot.

Finally, the tube 1 made of cigarette paper is surrounded by a sleeve to be placed in the mouth 7 which is formed from a ribbon of porous material 8. The sleeve 7 surrounds the tube 1 at its end carrying the filter element 3, on a sufficient distance to cover at least this filter element. In the example illustrated, the sleeve 7 slightly exceeds the filter element 3 and covers part of the tobacco receiving compartment 6.

According to the invention, the tube 1 made of cigarette paper is provided with at least one air permeable ventilation zone, which is situated so as to cover part of the filter element 3 and which is produced before formation of the tube. In the example illustrated, one can observe a ventilation zone consisting of openings 9 which are precut in the cigarette paper and are completely interposed between, on the one hand, the filter element 3 peripherally permeable to air, and on the other hand, the ribbon of porous material of the sleeve. The ventilation openings 9 can advantageously be disposed peripherally on the tube at a uniform distance from the end of the mouth side of the tube. Without this ventilation zone of the cigarette paper, which is little or not breathable per se, no ventilation is possible, despite the air permeability of the casing 5 of the filter element 3 and the porosity of the socket 8. It is obvious that it is possible to provide several ventilation zones axially spaced from one another.

It can be provided that the sleeve 8 is very porous in its entirety or that it is more permeable to air in a so-called permeability zone, the rest of the sleeve can even then be of low porosity.

In the example illustrated in FIG. 1, the ribbon 8 of the socket to be placed in the mouth 7 has a predetermined air permeability (which may be low) and comprises at least one zone of higher permeability. In FIG. 1, this upper permeability zone is formed of perforations 10, arranged in parallel peripheral rows, in the axis of the ribbon. This permeability zone is located so as to cover at least partially the ventilation zone of the cigarette paper. The rows of perforations 10 extend in the example illustrated so as to cover the openings 9. The ribbon of material 8 is provided with these perforations 10 before winding the sleeve 7 around the tube 1.

In the assembled state of the tube, ventilation can be carried out, during aspiration into the filter element, by air passing through the perforations 10 covering openings 9, then through these openings 9 and finally through the 'envelope 5 of the filter element. In the example illustrated the perforations 10 cover openings 9 which have a dimension in the axial direction of the tube 1 which is greater than the width of the rows of perforations 10. The air flow is thus regulated by the number of perforations 10 superimposed on openings 9. The manufacturer can thus offer cigarette paper tubes with filter tips which will allow the manufacture of differently ventilated cigarettes according to this data.

When the tape 8 is made of a material of high and uniform porosity and is not perforated, the air flow rate is regulated by this porosity value and by the surface of the tape which covers openings 9. The manufacturer can then play on the porosity of the tape 8 and / or on the cut surface of the openings 9 to adjust the ventilation of the cigarettes obtained by the tubes according to the invention.

According to the embodiment illustrated in FIG. 3, the ventilation zone of the tube comprises openings 9 ′ similar to those already described, which on a part of their surface project beyond the filter element and overflow into the tobacco receiving compartment 6 They are however still advantageously covered with the sleeve 7 which provides mechanical support to the openwork cigarette paper at this location.

There is thus obtained, in addition to the ventilation of the filter, a ventilation of the tobacco which can also be adjusted as a function of the number of perforations 10 superimposed on the parts of openings 9 in direct contact with the tobacco. In Figure 2 there is schematically illustrated a method of manufacturing tubes according to the invention.

From a reel 11, a ribbon 12 of cigarette paper is continuously unwound. This is transferred flat over a predetermined distance during which in known and usual manner the cigarette paper is printed by a printing device, to receive for example the impression of a commercial mark. In the example illustrated, this printing is carried out between two printing rollers 13 and 14 known per se. This printing process is, in a known manner, synchronized mechanically or electronically so that the printing is positioned exactly with respect to the filter element which will be brought to the ribbon and with respect to the cutting. tubes.

This synchronization can be used to implement on the ribbon 12 driven flat a perforating device formed by two perforating rollers 15 and 16. This perforating device can obviously be placed before the printing device, but it must anyway be arranged before the location where the tape is caused to wrap the filter element.

As a perforating device, use may be made of a cylinder provided peripherally with punches (for example the roller 15) and a cylinder provided peripherally with corresponding counter-knives (for example the roller 16) in which the punches fit perfectly. In this counter knife cylinder the cut material is safely removed. This technique is commonly applied for example in machines making perforations at the edges of chain forms. We can also refer to GB-A-2264038 already cited, which describes such a device.

Other perforation devices can of course also be provided, and even devices involving step-by-step advancement of the tape. However, advantageously devices that do not slow the continuous movement of the tape will be used.

The size and position of the openings 17 made in the tape must be determined according to the degree of ventilation desired. Consideration should also be given to the reduction in resistance to the tension that the ribbon undergoes following the perforation. During the production process a certain tensile force is applied to the tape of cigarette paper and it is necessary to avoid that, by a rupture of the tape due to too strong reduction in its tensile strength, a shutdown of the installation does not be provoked.

The position of the openings 17 cut from the ribbon advantageously take account of the surface of the paper which must be available for the application of the line of adhesive intended to hold the filter element 18 in place and to allow its wrapping by the paper ribbon and for the application of the line of adhesive necessary for closing the sleeve to be placed in the mouth when it is wound around the tube. Sufficient space will therefore be provided between two openings 17 for the application of a bead of adhesive which will keep the filter element deposited on the tape 12. The filter element 18 is then in a known manner wrapped in the tape. cigarette paper and the openings 17 arranged transversely to the longitudinal axis of the tape are applied to the periphery of the filter element 18. A bead of glue is applied longitudinally to the cigarette paper so as to extend along of an edge of the ribbon and during the wrapping it allows the closing of the cigarette paper tube 19.

In the example illustrated, the tube 19 is sectioned halfway between two successive filter elements 18. Each filter element 18 is thus provided, in a known manner, with a tobacco receiving compartment at each end. These double tubes are then, in a known manner, moved transversely to the direction of movement of the tape 12, to be wound in a tape of porous material 20. This tape is made of highly porous material or it has for example two permeability zones , the upper being formed of microperforations 21. These microperforations are here arranged in rows which extend along the longitudinal direction of the ribbon 20. After this winding, the sleeves formed are closed by gluing. Obviously the bead of adhesive used must not block the perforated area.

Finally after this operation, the double tubes are sectioned in a known manner, not shown, in the middle of the filter element so as to form two tubes according to the invention, separated.

It is obvious that one can also implement a manufacturing process which produces not double tubes, but directly single tubes, adapting the process accordingly. The arrangement and the shape of the openings 17 and the perforations 21 may vary, for example if it is desired to ventilate part of the tobacco receiving compartment simultaneously.

It should be understood that the present invention is in no way limited to the forms and embodiments described above and that many modifications can be made thereto without departing from the scope of the appended claims.

One could for example provide a ribbon of cigarette paper which, already in the reel, has a ventilation zone formed from a part of the highly porous paper, unlike the rest of the ribbon, which could be obtained for example by treatment chemical tape prior to winding.

Claims

1. Tube (1, 19) made of cigarette paper (2, 12) comprising,

- at least one filter element (3, 18) housed in the tube at a first end thereof and peripherally permeable to air, - an empty tobacco receiving compartment (6), located in the tube (1, 19) between the filter element (3, 18) and a second end of the tube, axially opposite the first, this compartment being to be filled with tobacco by a user to make a cigarette, and - a socket to be placed in the mouth ( 7), formed of a ribbon (8,

20) of porous material and enveloping the tube (1, 19) at its first end over a distance sufficient to cover at least said at least one filter element (3, 18),

- the cigarette paper tube (1, 19) having at least one breathable zone, characterized in that the cigarette paper tube (1, 19) has at least one breathable ventilation zone which is situated so as to cover at least a part of said at least one filter element (3, 18) and which is produced on the cigarette paper (2, 12) before forming the tube (1, 19).

2. cigarette paper tube according to claim 1, characterized in that the ventilation zone consists of openings (9, 17) precut in the cigarette paper (2, 12), which are completely interposed between, d ' on the one hand, the filter element (3, 18) peripherally permeable to air and, on the other hand, the strip (8, 20) of porous material of the sleeve (7).

3. cigarette paper tube according to claim 1, characterized in that the ventilation zone comprises peripheral openings (9 ') precut in the cigarette paper (2, 12), which, on a part of their surface, are interposed between, on the one hand, the filter element (3, 18) peripherally permeable to air and, on the other hand, the strip (8, 20) of porous material of the sleeve and which, on another part of their surface, protrude into the compartment receiving tobacco (6) empty.

4. Cigarette paper tube according to claim 3, characterized in that, in said other part of their surface, the openings (9 ') in the tube (1, 19) are completely covered by the tape (8, 20) of porous material from the sleeve (7) to be placed in the mouth.

5. cigarette paper tube according to any one of claims 1 to 4, characterized in that the ventilation openings

(9, 9 ', 17) are disposed peripherally on the tube (1, 19) at a uniform distance from said first end.

6. cigarette paper tube according to any one of claims 1 to 5, characterized in that the socket to be placed in the mouth (7) is made of a ribbon (8, 20) of porous material which has a permeability to the air is predetermined and comprises at least one upper permeability zone, which is situated so as to cover at least partially said at least one ventilation zone of the cigarette paper tube and with which the ribbon of material is provided before winding of the sleeve ( 7) around the tube (1, 19).

7. A cigarette paper tube according to claim 6, characterized in that said at least one upper permeability zone comprises perforations (10, 21) in the ribbon of porous material.

8. A cigarette paper tube according to claim 7, characterized in that the aforesaid perforations (10, 21) are arranged in parallel peripheral rows covering said at least one ventilation zone of the tube.

9. cigarette paper tube according to claim 8, characterized in that the aforesaid perforations (10, 21) cover openings (9, 9 ', 17) of said at least one ventilation zone which have a dimension in the axial direction of the tube which is greater than that of the upper permeability zone formed by these perforations.

10. A cigarette paper tube according to any one of claims 1 to 9, characterized in that the filter element (3, 18) comprises a core of absorbent material (4) and a casing (5) of a permeable material to the air.

11. A method of manufacturing cigarette paper tubes comprising

- an unwinding of a ribbon of cigarette paper,

a wrapping of said at least one filtering element by the tape so as to form a cigarette paper tube,

a sectioning of the cigarette paper tube provided with said at least one filtering element, and

a winding of a ribbon of porous material around said tube so as to form a sleeve covering at least said at least one filter element, characterized in that it further comprises a shaping of the ribbon of cigarette paper before formation of the tube so that it has at least one air permeable ventilation zone which, after said wrapping, is located so as to cover at least a part of said at least one filter element.

12. The method of claim 11, characterized in that it comprises a displacement of the strip of cigarette paper in a longitudinal direction and in that said shaping comprises a cutting of openings arranged substantially transversely to this direction, at regular distances.

13. Method according to either of claims 11 and 12, characterized in that the strip of porous material of the sleeve to be placed in the mouth has a predetermined air permeability and in that the method comprises a shaping a ribbon of porous material before said winding so that it has at least one zone of higher permeability which, after winding, at least partially covers said at least one zone of ventilation of the tube.

14. Method according to claim 13, characterized in that it comprises a displacement of the ribbon of porous material in a longitudinal direction and in that said shaping of this ribbon comprises a perforation in the longitudinal direction of rows of perforations arranged parallel to this direction .

15. Method according to any one of claims 11 to 14, characterized in that the sectioning of the tube is carried out so as to form a symmetrical empty tobacco receiving compartment on either side of the filter element, in that that, after its shaping, the strip of cigarette paper has two ventilation zones each arranged after said wrapping so as to cover at least partially a respective end of the filter element.

16. The method of claim 15, characterized in that the ribbon of porous material has a predetermined air permeability and in that the method comprises shaping the ribbon of porous material before said winding so that it has a zone of higher permeability covering, after winding, at least partially each ventilation region of the tube as well as a sectioning of the filter element in its center with the formation of two cigarette paper tubes.

17. The method of claim 12, characterized in that the cutting of the openings in the cigarette paper tape is carried out on the cigarette paper tape arranged flat.

18. The method of claim 14, characterized in that the perforation of the ribbon of porous material is carried out on this ribbon disposed flat.