EP1499769A1

EP1499769A1 - Thermo-adhesive mesh

Info

Publication number: EP1499769A1
Application number: EP03740560A
Authority: EP
Inventors: Thierry Gautreau
Original assignee: Chavanoz Industrie SARL
Current assignee: Chavanoz Industrie SARL
Priority date: 2002-04-03
Filing date: 2003-04-03
Publication date: 2005-01-26
Also published as: US20060035547A1; FR2838141B1; FR2838141A1; WO2003083198A1; CA2481249A1; JP2005527711A; AU2003258849A1

Abstract

The invention relates to a textile mesh (5A), embodied as a system of crossed, non-woven threads, comprising at least one layer of warp thread (1, 1') and at least one layer of weft thread (2), the warp (1,1') and weft (2) threads being connected to each other by means of a bonding agent (3). Said textile mesh (5A) is coated on at least one face (A) thereof by a thermally-reactivating glue (3), to glue the mesh (5A) to an external element, characterised in that the viscosity of said glue (3), measured at a temperature of 230 °C according to standard ASTM-D3236-88, is less than or equal to 40 Pa.s.. The invention further relates to textile meshes.

Description

THERMO-ADHESIVE GRID

TECHNICAL AREA

The present invention relates to the general technical field of textile grids formed of a network of warp and weft yarns, such grids acting in particular as reinforcements or supports in different industrial applications.

The present invention relates to a textile grid formed by a network of crossed or superimposed nonwoven threads comprising at least one ply of warp threads and at least one ply of weft threads, the warp and weft threads being linked together by a binder, said textile grid being coated on at least one of its faces with a thermally reactivable adhesive for laminating the grid on an external element, for example in order to reinforce it.

The present invention also relates to any finished or unfinished industrial product incorporating a textile grid according to the invention.

The present invention also relates to a method of manufacturing a textile grid in which a network of crossed or superimposed nonwoven threads is produced, comprising at least one ply of warp threads and at least one ply of weft threads to form a grid. primitive, and in which at least one of the faces of said primitive grid is coated with thermally reactivatable adhesive.

The present invention finally relates to a device for implementing at least part of the above-mentioned method. PRIOR ART

It is already known to produce grids industrially formed from a network of crossed nonwoven threads, the threads being bonded together at their crossing points by impregnation with a binder, of the thermoplastic adhesive type or the like. The known grids can, for example, use at least two layers of warp yarns which are superimposed or even offset, each pair of plies having interposed between them at least one ply of weft son.

According to these known embodiments, the warp threads and the weft threads are linked together at their crossings by a binder creating a series of bonding points, with a view to obtaining a textile grid having a finished structure and mechanically stable. .

The grids produced according to this technique generally give satisfaction and serve as reinforcements or supports in very varied technical fields such as, for example, without limitation, in the building industry as supports for parquet and ceramics, or coatings wall and carpet, in the paper industry, or even as reinforcing elements in synthetic or other foams.

Generally, the grids intended to serve as reinforcements are assembled by bonding to the surface of the element to be reinforced. Such an assembly is also called laminating. This lamination can be done using an external supply of glue.

In the case in particular of the grids described above, such an addition of adhesive is not necessary: the binder impregnating the grid is capable of ensuring this bonding function. In this case, it suffices to position the grid against the surface of the element to be reinforced, to thermally reactivate the binder using a heating device, i.e. to bring it to a temperature at which it has an adhesive character, which will allow the joining of the 'element to reinforce and grid; this joining remains effective once the binder has returned to a temperature below the above temperature.

Nevertheless, it appears that the textile grids impregnated with a reactivable binder for laminating known to date suffer from a certain number of drawbacks, and in particular drawbacks linked to the relatively high temperature necessary to reactivate the binder in such a way confer its adhesive character.

Indeed, the binders used to date are generally polymeric adhesives in aqueous phase or solvent crosslinked or not. The reactivation of such adhesives requires temperatures of the order of 150 ° C to 300 ° C. Such temperature levels therefore induce significant laminating times, since as a function of the time necessary for the heating device to reach the reactivation temperature, it being understood that the higher this temperature, the longer this temperature rise time will be. Such temperature levels also prohibit laminating on certain materials that would not support them. In particular, it is therefore impossible to laminate such textile grids to synthetic foams such as those used in the manufacture of automobile seats, for example made of polyethylene or polyurethane. Such foams are in fact generally altered or destroyed at such temperature levels. Finally, the higher the reactivation temperature, the greater the energy input required for this reactivation, requiring heavy equipment and therefore costly. This leads to an increase in the cost price of the reinforced products obtained, which constitutes an industrial disadvantage.

STATEMENT OF THE INVENTION

The objects assigned to the present invention therefore aim to remedy the various drawbacks of the heat-activated textile grids of the prior art mentioned above, and to propose a new textile grid having improved properties and which is easy to use and at a reduced cost, said grid being formed by a network of crossed non-woven threads, and being coated with a thermally reactivable glue to laminate the grid to an external element.

Another object of the invention is to propose a new textile grid coated with a thermally reactivable adhesive which is suitable for laminating on most materials.

Another object of the invention is to propose a new textile grid coated with a thermally reactivable adhesive capable of improving the general mechanical and chemical resistance of the grid.

Another object of the invention is to propose a new textile grid allowing a clean bonding without solvent.

Another object of the invention is to propose a new method of manufacturing a textile grid coated with reactivable glue which is particularly simple and quick to implement. Another object of the invention is to propose a new device for implementing the method according to the invention which makes it possible to produce grids with high levels of glue in a simple and rapid manner.

The objects assigned to the invention are achieved using a textile grid formed by a network of nonwoven cross-threads, comprising at least one layer of warp threads and at least one layer of weft threads, the threads of warp and weft being linked together by a binder, said textile grid being coated on at least one of its faces with a thermally reactivable glue to laminate the grid to an external element, characterized in that the viscosity of said glue, measured at a temperature of 230 ° C according to standard ASTM-D3236-88, is less than or equal to 40 Pa.s.

The objects assigned to the invention are also achieved using a method of manufacturing a grid according to the invention, characterized in that it comprises at least:

a step of crossing the warp and weft threads to form a primitive grid,

a coating step where at least one of the faces of said primitive grid is coated with thermally reactivable adhesive, the viscosity of which is measured at a temperature of 230 ° C. according to the standard

ASTM-D3236-88, is less than or equal to 40 Pa.s.

Finally, the objects assigned to the invention are also achieved by a device for implementing the method according to the invention, characterized in that it comprises: - a tank intended to contain thermally reactivable glue, the viscosity of which, measured at 230 ° C according to standard ASTM-D3236-88, is less than or equal to 40 Pa.s, said tank being heated so as to keep the glue in melting, and having at least one opening, - a cylinder rotating around its axis of symmetry, said cylinder being arranged and positionable relative to the tank so as to continuously feed, due to its rotation, glue in fusion through of said opening, and continuously depositing this molten glue on the face of a textile grid to be coated with glue, - a conveyor means for bringing said textile grid substantially into contact with the cylinder.

SUMMARY OF DRAWINGS

Other particular objects and advantages of the invention will appear in more detail on reading the description which follows, and with the aid of the appended drawings below, purely by way of non-limiting illustration, in which:

- Figure 1 illustrates, in a side view in section, a detail of the structure of a textile grid according to the invention.

- Figure 2 illustrates, in a top view, a detail of a grid according to the invention.

- Figure 3 illustrates, in a schematic view in longitudinal section, the principle of embodiment and operation of a device for implementing the method according to the invention. - Figure 4 illustrates a detail of the device shown schematically in Figure 3 on an enlarged scale.

BEST WAY TO IMPLEMENT THE INVENTION

According to the invention, the textile grid 5A according to the invention is formed by a network of nonwoven crossed threads, comprising at least one ply of warp threads 1, 1 ', and at least one ply of weft threads 2.

The wires thus delimit empty zones, so that the grid has an openwork structure.

Advantageously, the textile grid according to the invention comprises at least two plies of warp threads 1, 1 ′ between which is interposed at least one ply of weft threads 2.

As is well known to those skilled in the art, the construction of the network of warp threads 1, 1 'and weft threads 2 is obtained by shifting the warp threads 1, 1' and weft 2 without superposition (see Figure 2), or on the contrary by ensuring a superposition of the wires.

Likewise, the network of warp 1 and weft 2 threads can be obtained by crossing the warp and weft threads at 90 ° (square construction), or according to a different angular inclination, for example bidirectional or tri- directional.

Without limitation, the texture of the textile grid according to the invention may vary from 0.4 thread per centimeter to 10 threads per centimeter, for warp and weft threads. By way of non-limiting example, and as is well known to those skilled in the art, any type of textile thread commonly used to date in the production of textile grids may be used, and for example glass threads (having a linear mass can for example vary from 11 to 544 tex) or polyester (having a linear mass which can vary for example between 78 Dtex and 1100 Dtex).

According to the invention, the warp 1, 1 ′ and weft 2 threads are linked together by a binder creating a series of bonding points at the intersections of the network of threads.

Within the meaning of the invention, any binder commonly used to date in the technical field considered may in particular be used, and in particular any polymer adhesive of the thermoplastic polymer binder type.

By way of non-limiting example, the network of threads forming the textile grid in accordance with the invention can thus be made using synthetic latex (SBR), PVAC, PVC plastisols, polyvinyl alcohol (PVA), conventional iron-on impregnations, polyurethane binders or acrylic binders for example.

According to the invention, the textile grid 5A is coated on at least one of its faces A with a thermally reactivable adhesive 3 to laminate the grid to an external element.

Within the meaning of the invention, a thermally reactivatable adhesive is a material which, when it is going to be subjected to a characteristic temperature known as thermal reactivation, will have an adhesive character allowing it to become integral with an external element. This solidarity is lasting, a times the material returned to a temperature below said thermal reactivation temperature.

Thus, the reactivatable adhesive material can have a non-adhesive nature at room temperature and be in the solid state, while when it is heated to at least its thermal reactivation temperature, it takes the form of a liquid, which can be very viscous, with good adhesive power.

The thermal reactivation is done using a heating means which can be of any known type, and for example using high frequency or infrared radiation, conduction or convection phenomena.

According to an essential characteristic of the invention, the viscosity of the adhesive 3, measured at a temperature of 230 ° C according to standard ASTM-D3236-88, is less than or equal to 40 Pa.s.

Preferably, the viscosity of said adhesive, measured at a temperature of 200 ° C according to standard ASTM-D3236-88, is less than or equal to 30 Pa.s.

Even more preferably, the viscosity of said adhesive, measured at its application temperature (the value of which is systematically available from the manufacturer) according to standard ASTM-D3236-88, is less than or equal to 30 Pa.s.

Such a viscosity characteristic is representative of an adhesive which can be reactivated at temperatures which may be relatively low, and which may drop, for example, up to 70 ° C. Thus, the textile grid 5A according to the invention can be laminated without damage to materials which do not withstand high temperatures, and in particular synthetic foams.

Advantageously, the adhesive 3 is of the “hot-melt” type. A “hot-melt” type adhesive is a 100% hot-melt adhesive, also called 100% active adhesive, which comprises a thermoplastic material capable of passing from a non-adhesive solid state to an adhesive viscous state, and this in a reversible manner. The solid state is obtained when the material is subjected to a temperature below a characteristic temperature called the thermal reactivation temperature, which can vary for example between 70 ° C. and 180 ° C. depending on the formulation of the adhesive. When the material is subjected to a temperature greater than or equal to this thermal reactivation temperature, it is in the viscous and adhesive state mentioned above.

Hot-melt adhesives are well known as such. They consist of a mixture of polymers including:

- one or more polymers or copolymers of high molecular weight, for example polyethylene vinyl acetate, polyamide, polyester, epoxy, polyethylene, - waxes of the paraffin type of low molecular weight

(800-1000 g.mol- ¹ ),

- low molecular weight rosin-type tackifying resins,

- additives, for example anti-UV or antioxidants.

They allow a clean and solvent-free bonding, and can be used with many materials, whether cellular or solid, such as polymers, including polyolefins, natural materials, metals, composites, ceramics.

Thus, the grid according to the invention can be laminated to most materials, so as to form a complex.

The grid according to the invention is thus also capable of being compatible with secondary or final transformations of the complex, such as for example thermoforming of the complex.

The textile grid according to the invention can use any type of known “hot-melt” glue.

The textile grid 5A according to the invention may be covered with thermally reactivable adhesive 3 on at least one of its faces according to a surface mass (or sizing weight) of for example between 2 and 300 g / m ² .

Advantageously, the ratio of the mass of glue 3 coating the network of wires to the mass of said network of wires may be between 50 and 400%, and preferably between 100 and 300%.

The use of an adhesive 3 of the “hot-melt” type thus makes it possible to produce large and uniform adhesive deposits, since the adhesive 3 consists entirely of adhesive material, and not of an adhesive-solvent mixture.

This makes it possible to produce a substantially waterproof protective layer on the warp 1, 1 ′ and weft 2 yarns. Preferably, the binder of the textile grid according to the invention is formed by said thermally reactivable adhesive 3, said adhesive thus ensuring a double function:

- holding of the wires, so that the grid has a finite and mechanically stable structure (i.e. which stands by itself, independently of any interaction with an external element),

- And bonding when the grid is used as reinforcement, and for this purpose is laminated to the element to be reinforced.

It is thus unnecessary, in this case, to carry out a primary impregnation of binder to link the warp 1, 1 ′ and weft 2 yarns together.

In general, the grids according to the invention have a mechanical resistance to rupture of between approximately 19 and 1970 Newtons over 5 cm. The coating of hot-melt type adhesive improves the tensile and tear strength of the grid. It also allows an improvement in the flexural modulus and the stiffness of the grid.

The textile grid 5A in accordance with the invention can also be advantageously used as reinforcement for automobile wheelchair foam, since the reactivation temperature of the adhesive is compatible with the temperature that such foam can endure. This makes it possible to produce mechanically resistant armchairs while giving them a high-end connotation.

The textile grid according to the invention can be used to replace the polyvinyl chloride reinforcements, usually used for example for car seats. Such use has the important advantage that, in the event of combustion (accidental or end of product life) of the seat, the grid does not release toxic products, while polyvinyl chloride releases chlorine.

The textile grid according to the invention will also be particularly well suited for assembling floor coverings of the tiling, parquet type, or for reinforcing wiping cloths. It can also be used for the production of crack cover adhesives.

The grid according to the invention thus makes it possible to be adapted to the conditions of use of the final product. It also allows recycling of reinforced products at the end of their life, since due to the reversible nature of the glue used (character which aqueous glues do not have), the grid can be separated at will from the element it reinforces.

According to the invention, the process for manufacturing a textile grid according to the invention and as described above implements a series of production steps, at least of which:

a step of crossing (not shown) the warp 1, 1 ′ and weft 2 threads to form a primitive grid 5; such a production step is well known to those skilled in the art, and can for example be carried out by any suitable method,

a coating step (see FIGS. 3 and 4), where at least one of the faces A of said primitive grid 5 is coated with thermally reactivable adhesive 3 whose viscosity, measured at a temperature of 230 ° C. according to the ASTM standard- D3236-88, is less than or equal to 40 Pa.s, or more preferably is less than or equal to 30 Pa.s, when it is measured at 200 ° C according to the same standard. Preferably, the coating step is carried out immediately after the crossing step.

Thus, at the end of the wire crossing step, the grid 5 does not stand by itself, and the coating step makes it possible both to give the grid 5 a clean mechanical strength and to provide it with a thermally reactivable glue, for subsequent lamination.

In this case, the thermally reactivable glue 3 therefore acts both as a binder and as a lamination glue.

Preferably, during the coating step, the warp 1, 1 ′ and weft 2 threads are simultaneously covered with glue 3.

Advantageously, said adhesive 3 is of the “hot-melt” type.

Advantageously, during the coating step, the face A of the primitive grid 5 is coated with glue 3 which can be reactivated thermally, by tangential passage against at least part of the lateral surface 7A of a rotary cylinder 7 coated with said glue 3 in fusion.

The use of a cylinder 7 allows an application "with the roller", which allows a deposit of substantially uniform and regular adhesive on the primitive grid 5, without bead.

The use of a cylinder 7 makes it possible to avoid the drawbacks of conventional technologies for coating “hot-melt” type products, such as machines with “lip nozzles”. Such machines, if they can be successfully used for coating closed supports, such as paper or fabric panels over large widths, are however ineffective for coating open substrates over suitable widths, with a low inherent mechanical strength, such as a primitive grid, without causing beads of glue which make the product very difficult to use.

According to a variant of the method according to the invention, a primary bonding step occurs between the step of crossing the wires and the coating step. During this primary connection step, the primitive grid 5 is impregnated with a binder, so as to bond the weft 2 and warp 1 yarns together. Thus, a method according to this variant implements, after the primary bonding step, a grid having its own mechanical strength imparted by the primary impregnation of binder; the coating step, in this case, is only intended to provide the grid with a layer of thermally reactivable adhesive.

The primary bonding step can be carried out by any method of the prior art, which are well known to those skilled in the art.

Any binder conventionally used for such an application can be used during this step, and in particular the binders formed by a polymer adhesive, or those mentioned above.

The invention also relates to a device for implementing the method according to the invention.

This device includes:

- a tank 6 intended to contain glue 3 which can be reactivated thermally, the viscosity of which, measured at 230 ° C. according to standard ASTM-D3236-88, is less than or equal to 40 Pa.s, and so preferential is less than or equal to 30 Pa.s at 200 ° C., said tank 6 being heated by any suitable means, so as to keep the glue 3 in fusion, and having at least one opening,

- A cylinder 7 rotating around its axis of symmetry X, said cylinder 7 being arranged and positionable relative to the tank 6, so as to continuously feed, due to its rotation, glue 3 molten through said opening , and continuously depositing this glue 3 in fusion on the face A of a textile grid 5 to be coated with glue, - a conveying means (not shown) for bringing said grid 5 substantially into contact with the cylinder 7.

Advantageously, the cylinder 7 is also heated to a temperature for example between 70 and 300 ° C, and preferably between 100 ° C and 220 ° C.

This heating can be achieved by any known means.

Advantageously, the rotating cylinder 7 is arranged so that any zone of at least part of its lateral surface 7A is alternately in contact:

on the one hand with the glue 3 in fusion, through said opening, so that the part of the lateral surface 7A is coated with glue,

- And on the other hand with the face A of the textile grid 5 to be coated with glue, brought in a longitudinal translational movement (the direction of which is materialized by the arrow 8) substantially tangentially to the lateral surface, so as to deposit at less a part of the glue coating said part of the lateral surface 7A on said face A.

Preferably, as shown in FIGS. 3 and 4, the cylinder 7 is positioned between the opening and the face A of the grid to be coated with glue 3.

The cylinder 7 is driven by a rotational movement (materialized by the arrow 9) around its axis of symmetry X, which gives its lateral surface 7A a certain linear speed. The conveying means, which can be of any known type (for example a conveyor belt), gives the grid 5 to be coated with adhesive a longitudinal translational movement which takes place at a certain speed of movement.

Preferably, the longitudinal translational movement 8 takes place at a displacement speed which is substantially equal to the linear speed of the lateral surface 7A of the cylinder. In this way, the quantity of glue deposited on the warp threads is substantially equal to the quantity deposited on the weft threads. The difference in linear speed between the lateral surface 7A of the cylinder 7 and the primitive grid 5 to be coated makes it possible to obtain a thickness E1 of adhesive on the warp threads 1, 1 ′ which is different from the thickness E2 of adhesive on the weft yarn 2.

The tank 6 is in turn made up of a body 6C provided with a doctor blade 6A for calibrating the coating of the cylinder, that is to say for controlling the thickness E of adhesive depositing on the lateral surface 7A of the rotary cylinder. 7. A second doctor blade 6B opposite the first makes it possible to close the tank 6 in cooperation with the first doctor blade 6A, during machine stops. It is of course conceivable to design a device using two cylinders to coat a primitive grid 5 of glue 3 on its two faces, simultaneously or not, without departing from the scope of the invention.

It is interesting to note that, in most cases, the textile grids are thin enough that a coating on one side is sufficient to obtain a grid coated on both sides with glue.

The device according to the invention thus makes it possible to coat, for example, grids whose width can vary between 0.2 and 5 m, at a speed of, for example, between 0.4 and 150 m per minute. The control of the linear speed differentials between the cylinder and the grid, that is to say the control of the difference between the linear speed of the cylinder and the speed of movement of the grid, makes it possible to control the distribution of the adhesive deposit between the warp and weft threads, avoiding any unwanted bead.

POSSIBILITY OF INDUSTRIAL APPLICATION

The invention finds its industrial application in the field of textile grids intervening in particular as reinforcements or supports.

Claims

- Textile grid (5A) formed by a network of nonwoven crossed threads, comprising at least one ply of warp threads (1, 1 ') and at least one ply of weft threads (2), the warp threads (1 , 1 ') and weft (2) being linked together by a binder (3), said textile grid (5A) being coated on at least one of its faces (A) with a thermally reactivable adhesive (3) to laminate the grid (5A) on an external element, characterized in that the viscosity of said adhesive (3), measured at a temperature of 230 ° C according to standard ASTM-D3236-88, is less than or equal to 40 Pa.s.

- Textile grid (5A) according to claim 1 characterized in that it comprises at least two plies of warp threads (1, 1 ') between which said at least one ply of weft threads (2) is interposed.

- Textile grid (5A) according to claim 1 or 2 characterized in that the viscosity of said adhesive (3), measured at a temperature of 200 ° C according to standard ASTM-D3236-88, is less than or equal to 30 Pa. s.

- Textile grid (5A) according to one of claims 1 to 3 characterized in that the adhesive (3) is of the "hot-melt" type.

- Textile grid (5A) according to one of claims 1 to 4 characterized in that the weft son (2) and / or warp (1, 1 ') are made of glass.

- Textile grid (5A) according to one of claims 1 to 4 characterized in that the weft son (2) and / or warp (1, 1 ') are made of polyester. - Textile grid (5A) according to one of claims 1 to 6 characterized in that the adhesive (3) covers at least one of the faces (A) of the grid, according to a surface mass of between 2 and 300 g / m ² .

- Textile grid (5A) according to one of claims 1 to 7 characterized in that the binder is a polymer adhesive.

- Textile grid according to one of claims 1 to 7 characterized in that the binder is formed by the thermally reactivable adhesive (3).

-Process of manufacturing a grid according to one of claims 1 to 9 characterized in that it comprises at least:

a step of crossing the warp (1, V) and weft (2) threads to form a primitive grid (5),

a coating step where at least one of the faces (A) of said primitive grid (5) is coated with thermally reactivable adhesive (3) whose viscosity, measured at a temperature of 230 ° C. according to standard ASTM- D3236- 88, is less than or equal to 40 Pa.s.

-A method according to claim 10 characterized in that the viscosity of said adhesive (3), measured at 200 ° C, is less than or equal to 30 Pa.s.

-Manufacturing method according to claim 10 or 11 characterized in that the adhesive (3) is of the "hot-melt" type.

-A method according to one of claims 10 to 12 characterized in that during the coating step, the face of the primitive grid (5) is coated with thermally reactivatable adhesive (3), by tangential passage against the at least a part of the lateral surface (7A) of a rotary cylinder (7) coated with said glue (3) in fusion.

-A method according to one of claims 10 to 13 characterized in that it comprises a primary connection step intervening between the step of crossing the wires and the coating step, where the primitive grid (5) is impregnated with a binder, so as to bind the weft (2) and warp (1, l) threads together.

-A method according to claim 14 characterized in that the binder is a polymer adhesive.

-A device for implementing a method according to one of claims 10 to 13 characterized in that it comprises:

- a tank (6) intended to contain thermally reactivable adhesive (3) whose viscosity, measured at 230 ° C according to standard ASTM-D3236-88, is less than or equal to 40 Pa.s, said tank (6) being heated so as to keep the adhesive (3) in fusion, and having at least one opening,

- a cylinder (7) rotating around its axis of symmetry (X), said cylinder (7) being arranged and positionable relative to the tank (6) so as to continuously feed, due to its rotation, glue ( 3) in fusion through said opening, and in continuously depositing this adhesive (3) in fusion on the face (A) of a textile grid (5) to be coated with adhesive,

- Conveying means for bringing said textile grid (5) substantially into contact with the cylinder (7). -A device according to claim 16 characterized in that the rotating cylinder (7) is arranged so that any zone of at least part of its lateral surface (7 A) is alternately in contact:

on the one hand with the glue (3) in fusion, through said opening, so that the part of the lateral surface (7A) is coated with glue (3),

- And secondly with the face (A) of the textile grid (5) to be coated with glue, brought in a longitudinal translational movement (8) substantially tangentially to the lateral surface (7A), so as to deposit at least a part of the glue (3) coating said part of the lateral surface (7 A) on said face (A).

-A device according to claim 17 characterized in that the cylinder (7) is positioned between the opening and the face (A) of the grid (5) to be coated with glue.

-A device according to claim 17 or 18 characterized in that the longitudinal translational movement (8) is carried out at a speed which is substantially equal to the linear speed of the lateral surface (7 A) of the cylinder.