MXPA97002032A

MXPA97002032A - Procedure for the thermomechanical treatment of a vel cloth

Info

Publication number: MXPA97002032A
Application number: MXPA/A/1997/002032A
Authority: MX
Inventors: Kunze Bernd; Schulz Herbert
Original assignee: Reifenhaeuser Gmbh & Co Maschinenfabrik
Priority date: 1995-07-25
Filing date: 1997-03-18
Publication date: 1997-08-01

Abstract

The present invention relates to a process for the thermomechanical treatment of a fleece track consisting of filaments and / or fibers of a thermoplastic synthetic material, in a continuous process. The fleece track moves in the thermomechanical treatment and with uniform speed. The fleece track first passes a heat treatment station and is traversed at that station by a gaseous stream with a gaseous stream velocity and a pre-established gas stream temperature being heated to a preheat temperature. The preheated fleece track is subjected to mechanical treatment. The temperature of the gaseous stream and the velocity of the gaseous stream, on the one hand, as well as the treatment sections of the fleece track in the heat treatment station, on the other hand, are selected in such a way that the preheating temperature that below the temperature of the melting point of the filaments or fibers, at all speeds that the fleece track may acquire during operation including the zero speed. Apparatus is also presented to carry out the method according to the present invention.

Description

PROCEDURE FOR THE THERMOMECHANICAL TREATMENT OF A PE VELLON PATIO The present invention relates to a process for the thermomechanical treatment of a fleece cloth, consisting of filaments or fibers of thermoplasic synthetic material in a continuous process. The elements are indicated within the framework of the present invention as theoretically infinitely long individual synthetic yarns which are modeled to a non-woven fleece, where the individual filaments at the crossing positions and at the contact positions are joined by a closure of material in the fleece. Such fleece cloths are also indicated with spun fleece cloths. The fibers, on the other hand, indicate short synthetic elements in the form of fibers, which for example have been produced with the help of the Meltblown-Technik technique (meltblowing technique) and which form a Meltblown-Technik fleece whose fibers are also in place Contact junctions are joined in a material closure. The fleece cloth can be structured in one or more layers from several individual fleece cloths. Procedures for the thermomechanical treatment of a fleece track or cloth consisting of filaments and / or fibers made of thermoplastic material are known in different embodiments. A usual thermomechanical treatment is especially called Bondieren. With this it is understood that the fleece track simultaneously is provided with spot welding positions that with the predated diameter of the weld point as well as according to the measurement of a predated model is evenly distributed over the fleece track or cloth. Here the filaments or fibers in the area of the weld points are not complete so they do not weld together with one another to form plates. The welding points have a structure different from the shape of the plates, where the filaments or fibers are recognizable at the welding points at least as regards the texture. Such welding points are also indicated as jump or bonder points (Bonding). The bonderización causes an increase in the mechanical resistance of the p > Fleece. In order to achieve a definite increase in mechanical strength, all spot welding positions must have practically the same geometry and structure and be uniformly distributed throughout the length and width. The bonderización must be in this uniform sense. The bonderization is carried out according to the state of the art by using more directly the connection to the formation of the fleece in the apparatus for manufacturing such fleece and precisely with the help of rolls of embossing of bonderization point, this is heated to temperature with which the fleece runway is driven to the place where the bonderization points are made, no special influx is received. The bonder points thus achievable are capable of improvement in relation to the uniformity, also the quality of the bonder point connection can not be easily adjusted to the different operating conditions, for example in different or thick synthetic materials of the fleece or diameters of the filament of the different fibers. Another usual thermometric treatment is the stretching of the runway or strip of fleece finished in the longitudinal or transverse direction with the aid of suitable stretching apparatuses. Stretching also causes an increase in mechanical strength. This must also be carried out uniformly in the sense of the mentioned embodiments, depending on such measures it is known that the fleece track that runs towards the stretching apparatus or also in the apparatus itself preheat it and precisely with the help of infrared radiators. Also the measures for this known are able to be improved and especially in relation to the adjustment to the different operating conditions. The invention It is proposed to solve the technical problem of creating a procedure with which a thermomechanical treatment adjusted to the different operating relationships in the described sense is very uniform of a track or fleece made of filaments and in a simple way is possible. / or of fibers from a thermo-plastic synthetic material. In order to solve this problem, the object of the present invention is a method for the thermomechanical treatment for a fleece track consisting of filaments or fibers made of thermoplastic material in a continuous process with combination of the following characteristics, the fleece track moves in the thermomechanical treatment continuously and with uniform speed; the fleece pita first passes a heat treatment station and is traversed there by a gas stream of a predated velocity of gas stream as well as a temperature also preheated by preheating to a certain temperature; the preheated fleece track is subjected to mechanical treatment. where, the temperature of the gas stream and the velocity of the gas stream on the other hand the treatment section of the fleece track in the heat treatment station is selected in such a way that the temperature of p > overheating at all speeds that are assumed to have the fleece during operation including a null speed does not exceed the temperature of the melting point of the filaments and / or fibers. The fleece track or cloth is moved during the treatment according to its operation with a uniform velocity remaining of such a margin that it coincides with what is usually usual with the manufacture or treatment of a fleece track made of thermopipestic material. The method according to the invention prevails at all speeds. It is understood that the thermomechanical treatment takes place uniformly along and across the fleece cloth. The invention is based on the knowledge that with a gas stream passing through the fleece cloth it is possible to achieve a uniform preheating of the fleece cloth and in this connection a very uniform thermomechanical treatment of the fleece cloth and precisely in a uniform manner through it . The estimation rule according to the invention with which they are selected; the temperature of the gas stream and the velocity of the gas stream, on the one hand, as well as the treatment section of the mellon track in the heat treatment station, on the other hand, the preheating temperature at all speeds that they can acquire the fleece track during operation. including when the speed is zero, do not exceed the temperature of the melting point of the filaments or fibers. making sure that the fleece track will not receive any damage in the heat treatment station, but will remain in the optimum state for the next mechanical treatment. Preferably, the heat treatment station is operated in such a way that the preheating temperature coincides with the temperature of the gas stream. In this way the preheating temperature can be controlled very accurately. This also allows a simple adjustment to different operating conditions, for example in relation to different thermoplastic synthetic materials, a specified surface weight different from the fleece cloth and other different parameters. The parameters can always be selected in such a way that in the fleece track the melting temperature of the filaments or fibers does not exceed one when the gas stream temperature is higher than the melting temperature. 3i the temperature of the gas stream is less than the melt temperature will also not be reached with an infinitely long uniform treatment of a section of the fleece in the heat treatment station the melting point. Operating interruptions are mastered without major problem, the preheating temperature is measured when leaving the heat treatment station. In particular, within the scope of the invention there are several possibilities for idealizing and structuring the process, so that the fleece cloth can be brought to the thermal treatment station on a conveyor belt permeable to the current that is traversed from above and down by the gas stream. But there is also the possibility of conducting the fleece track in the heat treatment station between two conveyor belts permeable to the current, where they are traversed both from above and from below upwards by the gas stream. In this case, the fleece clue or cloth may be traced one after the other from top to bottom or bottom to top by the flow of gas flowing through it. It also presents the possibility that the fleece track both in the same place and at the same time in the heat treatment station is traversed by the gas stream, where the two gas streams collide with one another uniunisonous. According to a preferred embodiment of the invention, the preheated fleece track is provided in the mechanical treatment with bonderization points. For this purpose, the preheated fleece track in the mechanical treatment between the rollers of the heated bonderisation patches can be equipped with the connection points, it can presend cooling. The fleece track can also undergo mechanical stretching in the longitudinal direction and / or in the transverse direction and then be cooled. According to a preferred embodiment of the invention, the preheated fleece track is provided during the mechanical treatment with the bonder points first and then subjected to a stretching in the longitudinal direction and / or in the transverse direction. That within the framework of the invention as has already been stated in idealizing is such a procedure that the temperature of the gas stream and the velocity of the gas stream on the one hand as well as the treatment section of the fleece track on the thermal treatment station. on the other hand, it is selected in such a way that the pre-warming temperature in all those speeds that the fleece track could acquire, including the zero velocity, coincides practically with the temperature of the gas stream. The invention makes it possible to adjust the gas flow temperature and the treatment section of the fleece cloth in the heat treatment station of different thermoplastic synthetic materials and / or different fleece products. Within the framework of the invention, it is possible to work with an air stream representing a gas stream, preferably using a stream of dry air, using a gas stream or gas stream. Depending on the synthetic materials used and the temperatures, it is recommended to work with an oxygen-free gas stream. As a gas stream you can also use water vapor or a mixture of air and water vapor, if condensation is present in the fleece track, it is recommended to connect a drying stage afterwards. Next, apparatuses for carrying out the method according to the invention as well as some particularities of the method of the invention will be described in detail with reference to the drawings. Where: Figure 1 shows the diagram of an apparatus for carrying out the method according to the invention with a device for joining the track or cloth: Figure 2 the diagram of an apparatus for carrying out the process of according to the invention with device for stretching the fleece track: Figure 3 with Figures 3a and 3b which are a graphic representation to explain the procedure according to the invention. In order to carry out the method according to the invention, it consists of its basic structure of an apparatus 1 of fleece deformation, an endless circulating conveyor belt 2, a heat treatment station 3 and a mechanical treatment station 4. The endless conveyor belt 2 is determined to receive the track or cloth of hair that is forming so as to transport the formed fleece cloth. The heat treatment station 3 for the formed fleece cloth 5 has devices 6 so that a gas stream with a predated current velocity flows through the cloth 5- with a certain temperature in the gas stream. The current is indicated in Figure 1 by means of arrows. The mechanical treatment station 5 serves in the embodiment of Figure 1 to provide the fleece cloth 5 with bonderization points. The mechanical treatment station 4 is equipped for them with rollers "B". * The fleece cloth 5 is carried on the conveyor belt 2 through the heat treatment station 3 and the mechanical treatment station 4. The apparatus of fleece formation 1, a spindle 8 belongs to which a pre-processed plastic material is carried in a conventional manner from the spindle 8, corresponding filaments 9 pass, a cooling station 10 passes, and they enter a so-called stretching well. 11, to which a diffuser 12 is connected. The rollers 13 fulfill a sealing function and allow the process air to be vented in the direction of the indicated arrow.

Fig., Further presses the fleece track formed 5. against the transport belt 2, which is guided through a corresponding counter. The circulation path of the conveyor belt 2 is not indicated. The heat treatment station 3. is so aerodynamically shaped that a very uniform heat treatment occurs in the transverse direction of the fleece track 5. and also that. in the longitudinal direction of the track or fleece cloth 5. there are no upsetting positions or singularities, the mechanical treatment station 4. works as already mentioned with bonderizing rollers The fleece track 5. will leave the heat treatment station 3. with the temperature, that is, with a preheating temperature that is below the melting temperature of the filaments or the rows, and will be conducted to the treatment station 4. In contrast to this, FIG. 2 shows an apparatus for carrying out a method according to the invention which has a winding station of the fleece track 14. a heat treatment station 3, for the fleece track 5. and a mechanical treatment station 4. where the mechanical treatment station 4. is made as a stretching apparatus, the fleece track 5. wound on the reel or reel 15, occurs elsewhere and may have been manufactured in another time. For the thermal treatment station 3, what is already said is valid. The mechanical treatment station 4 is connected to the heat treatment station 3. with the result that the fleece track 5, which is at the preheating temperature, is conducted directly to the stretching apparatus, where a stretch is carried out in the direction longitudinal and / or in transverse direction.

The fleece track 5. - "orno has already been explained in relation to Fig. 1. It may have been equipped with bonderization points; ^ il they maintain their structure during the stretch, if it has been worked in accordance with the procedure of the In the partial Figs 3a and 3b of Fig. 3, graphical representations are recognized, in which the temperature and on the abscissa are set as ordinate The length of the treatment section, where the fleece track 5 , has undergone a heat treatment in station 3, and precisely when the fleece track 5 flows, with the gas stream for the thermal treatment, in Fig. 3a, there is the treatment section between Ll, L2; fleece 5, may have been introduced with three different inlet temperatures in the heat treatment station, which belong to the graphic representation according to Fig. Sa. In all three cases, the transport speed of the fleece track is equal and constant 5. It is recognized in Fig. 3a that the fleece track . a preheating temperature Tv penetrates or runs through the heat treatment station. which in all three cases is equal and constant. with this a constant preheating is achieved, even when the inlet temperatures of the fleece track 5 are different.

In Fig. 3b, the treatment section for the fleece track 5 is plotted in relation to the abscissa axis. corresponds to the sections Ll, L2, in the example of embodiment of Fig. 3b, the fleece track with different speeds VI may have been introduced. V2, V3. and constant inlet temperature in thermal treatment station. Here again, it is ensured by the treatment section that. the exit temperature and with this, the temperature Tv, of the fleece track 5, will be the same and precisely also when starting from the representation of Fig. 3b, the fleece track 5. that leaves the fleece formation station must stop because of a functioning disorder. It is understood. that in the heat treatment station, the lengths of the treatment sections can be varied.

Claims

CLAIMS 1. Procedure for the thermomechanical treatment of a track or strip of fleece consisting of filaments / or fibers made of a thermoplastic synthetic material. in a continuous procedure. with the combination of the following characteristics: a) the fleece track moves during the thermomechanical treatment continuously and with uniform velocity: b) the fleece track first passes through a heat treatment station and is traversed in that station by a stream of gas having a predated speed and temperature and heated to a preheating temperature; c) the pre-stressed fleece track is subjected to the mechanical treatment: where the temperature of the gas stream and the velocity of the gas stream on the one hand as well as on the other hand the treatment sections of the fleece track at the heat treatment are selected such that the preheat temperature at all speeds that the fleece track can acquire during operation including when it has zero velocity, will not exceed the temperature of the melting point of the filament and / or fibers .
2. Method according to claim 1. wherein the fleece track in the funtional treatment will move with a uniform speed that will correspond to the usual speeds of passage.
3. Method according to claims 1. 2. where the fleece track is conveyed to the thermal treatment station on a conveyor belt permeable to the current, being traversed from bottom to top by the gas stream.
Method according to one of claims 1, 2, wherein the fleece track is conveyed to the heat treatment station between two conveyor belts permeable to the current and is traversed both from bottom to top and from top to bottom, by the gas stream.
5. Method according to claim 4. wherein the fleece track is successively crossed by the gas stream from top to bottom or from bottom to top or in inverse sequence.
6. Method according to claim 4. where the fleece track is in the same place and at the same time traversed by a gas stream in the thermal treatment station.
7. Procedure according to one of claims 1 to ß. where the preheated fleece track is provided in the mechanical treatment with bonderization points.
Method according to one of claims 1 to 7, wherein the fleece track preheated during the mechanical treatment is provided between rolls of heated stampings of bonderization points with bonderization points.
Method according to one of claims 1 to 6, wherein the fleece track preheated in the mechanical treatment is subjected to a stretching in the longitudinal direction or to a stretch in the transverse direction and then cooled.
10. Method according to claim 1, wherein the fleece track in the mechanical treatment is first provided with bonder points and subsequently subjected to a stretching in the longitudinal direction or in the transverse direction.
The method according to one of claims 1 to 10, wherein the temperature of the gas stream and the velocity of the gas flow as well as the treatment sections of the fleece track in the thermal treatment station. on the other hand, they are selected in such a way that the preheating temperature remains at all the speeds that the fleece track can acquire during operation, including the zero speed, practically coinciding with the temperature of the gaseous current. .
12. Process according to one of claims 1 to 11, wherein the temperature of the gaseous stream, the velocity of the gaseous stream and the processing section of the fleece track. in the thermal treatment station it is adjusted to different thermoplastic synthetic materials, and / or different products of track or fleece band.
Method according to one of claims 1 to 12, where a stream of air is used as a gaseous stream.
14. Process according to one of claims 1 to 12, where a stream of dry air is used as a gaseous stream.
15. Method according to one of claims 1 to 12, wherein an oxygen-free gas stream is used.
Apparatus for carrying out a process for the thermomechanical treatment of a fleece track according to one of claims 1 to 15, which has: a fleece forming apparatus; a non-circular conveyor belt to receive the fleece track that is being formed as well as to transport the formed fleece track: thermal treatment station for the fleece track formed with an installation for crossing the fleece track with a stream have a predetermined gaseous current temperature and gaseous stream velocity: mechanical treatment station with bonderizing rollers. where the fleece track is conductive on the conveyor belt through the heat treatment station and through the mechanical treatment station, and where the temperature of the gaseous stream is below the melt temperature of the filament or fibers.
17. Apparatus according to claim 16, wherein in the direction of travel of the conveyor belt behind the mechanical treatment station with bonderizing rollers. a stretching device is arranged in which the fleece track is insertable and the conveyor belt before the stretching device retracts to the fleece forming apparatus. Apparatus for carrying out a process for the thermomechanical treatment of a fleece track according to one of claims 1 to 15, with a fleece track winding station, thermal treatment station for the fleece track formed with an installation for a current to pass through the fleece track formed by a gaseous stream of predetermined temperature and speed: a mechanical treatment station in the form of a stretching apparatus. where the fleece track is introduced to the stretching apparatus practically with the preheating temperature established in the heat treatment station. R E S U M N A procedure for the thermomechanical treatment of a fleece track consisting of filaments and / or fibers of a thermoplastic synthetic material. in a continuous procedure. The fleece track moves in the thermomechanical treatment and with uniform speed. The fleece track first passes a heat treatment station and is traversed at that station by a gaseous stream with a gaseous stream velocity and a pre-established gas stream temperature being heated to a preheat temperature. The preheated fleece track is subjected to mechanical treatment. The temperature of the gaseous stream and the velocity of the gaseous stream, on the one hand, as well as the processing sections of the fleece track in the heat treatment station, on the other hand, are selected in such a way that the Preheating is below the temperature of the melting point of the filaments or fibers, at all speeds that the fleece track may acquire during operation including zero speed. Apparatus is also presented for carrying out the method according to the present invention.