EP1387626A1

EP1387626A1 - Method for producing a touch-and-close fastener element

Info

Publication number: EP1387626A1
Application number: EP02737993A
Authority: EP
Inventors: Jan Tuma
Original assignee: Gottlieb Binder GmbH and Co KG
Current assignee: Gottlieb Binder GmbH and Co KG
Priority date: 2001-05-12
Filing date: 2002-04-25
Publication date: 2004-02-11
Also published as: WO2002091869A1; JP2004533943A; US20040119192A1; JP2008221848A; DE10123206A1

Abstract

The invention relates to a method for producing a touch-and-close fastener element (18) comprising a multitude of hook means (16), which are provided with a support (26) as one piece. In order to form said support (26), a plastic material in a free-flowing state is fed to a gap (22) located between a pressing device (24) and a shaping device (10) that is provided with cavities (14) for shaping the respective hook means (16). A support (26) having a small thickness can be obtained and/or the removal of the support (26) from the shaping device (10) is facilitated by feeding the plastic material together with the supporting part (32) into the gap (22), whereby the supporting part bears the support (26) between the pressing device (24) and the plastic material.

Description

Method of making an adhesive fastener part

The invention relates to a method for producing an adhesive fastener part with a plurality of interlocking means formed in one piece with a carrier, in which a plastic material in a flowable state for forming the carrier is fed to a gap between a printing device and a molding device which is provided with cavities for shaping the respective hooking means is provided.

In a generic method according to DE 196 46 318 A1, a thermoplastic plastic in a plastic or liquid state is formed in a gap between a pressure roller and a to produce an adhesive fastener part with a plurality of interlocking means formed integrally with a carrier in the form of thickenings (interlocking heads) Form roll supplied, the form roll is provided with cavities open to the inside and outside, and both rolls are driven in opposite directions of rotation to form the carrier in the gap between the rolls. The known form roller also has a screen, the cavities of which are preferably etched or have been produced by means of a laser, the finished interlocking means being produced solely by the fact that the thermoplastic material at least partially hardens in the open cavities of the screen of the molding roll. The thermoplastic used is preferably polypropylene, polyamide, polyethylene, and one or more of these plastics-containing copolymers or terpolymers. The thickenings of the stems are formed in the form of flattened or concave mushroom heads.

With this known method, fastener parts can be produced very inexpensively and with high quality, which work together with corresponding fastener parts to form conventional fastener fasteners, which can have comparable hooking means or which are formed from a fleece, loops or loop material. The adhesive closure part produced in this way is flexible and can adapt to different geometries; there is no significant inherent elasticity behavior of the closure. This means that the molded or extruded adhesive closure part essentially retains its predetermined outer shape and cannot be elastically stretched to any appreciable extent. Resilient properties of this kind are, however, also desirable in the case of adhesive fastener systems, for example if one wants to fix bandages elastically to body parts in the orthopedic or sports-medical field, which in addition to a support function should nevertheless be so elastic that they are the wearer of such bandages and support parts do not interfere. Furthermore, elastic fastener systems are particularly well suited to keep cable harnesses to each other and this in such a way in the automotive and aircraft ^"vehicle sector, and be able to use shipbuilding. The usual clip-like cable connector currently still predominantly used are for a difficult to attach and can not be solved non-destructively, in contrast to the described fastener systems.

In WO 95/10202, an elastic adhesive closure system has already been described, in which individual hooking means in the form of engagement hooks are placed on a thin, elastic plastic carrier; the associated manufacturing process alone is complex and therefore cost-intensive. The known method can also be used to connect hooking means that are not configured in any way to the elastic carrier part. Since the hooking means are furthermore only placed on the elastically stretchable film, the hooking means are not integrally connected to the carrier, which can lead to the hooking means being able to tear off the carrier, in particular when force is applied to the closure system.

PCT publications W099 / 1 7630 and W099 / 1 7631 also describe an elastic adhesive fastener part in which a relatively rigid and rigid plastic material for the hooking means is applied in the manner of a layer to an elastic plastic film as a further layer, the layer materials establish a firm connection with one another. So that the hooking means can then move elastically with the elastic layer film, the rigid layer material with the hooking means is preferably severed by cutting, so that the hooking means can then be moved away from one another with the stretching of the elastic film and can be reset until they adjoin the intersected ones Join areas of the rigid layer material again. The manufacturing processes involved are also complex and costly, and due to the use of multiple layer materials, the thickness of the elastic adhesive closure part is dimensioned large, which makes the use of this known system in so-called micro-fasteners, which are geometrically extremely small, not seem suitable. Also, it cannot be ruled out that the layer layers will separate, particularly after a long period of use and greater forces are introduced, which leads to the fact that this known adhesive closure system becomes unusable.

Based on this prior art, the object of the invention is to further improve the known methods for producing an elastic adhesive fastener part, in particular to provide a cost-effective and safe method for producing such fasteners, which can also be used after a long period of use high introductory staff work safely. Furthermore, the invention is based on the object of making available adhesive fastener parts as micro-adhesive fastener parts with an elastic structure. Claim 1 and / or claim 2 achieves an object in this regard with the entirety of its features.

Characterized in that, according to the characterizing part of claim 1, in addition to the supply of the plastic material into the gap, a support member is fed to the latter, which supports the support between the printing device and the plastic material in such a way that it is so thin in the shaping of the interlocking means that the carrier is provided with a predeterminable extensibility or elasticity with a suitable plastic material, it is ensured that the hooking means are integrally connected to the carrier during the shaping process. Accordingly, it is ensured that the hooking means are not unintentionally even with a long period of use and high forces Allow it to tear off from the tape-like or foil-like carrier, which can otherwise lead to the adhesive closure system becoming unusable.

Since the support part absorbs a large part of the compressive forces supplied via the pressure device during the shaping, the carrier, which is designed as an expandable or elastic part, can be made extremely thin, so that elastic micro-adhesive closures or those with high elasticity can be realized with the method according to the invention. The extremely thin design of the support also benefits its elasticity values, so that very good elastic properties can be achieved in this way. With the method according to the invention, very high production speeds can be achieved, so that the elastic adhesive closure part produced can be obtained very inexpensively.

Characterized in that, according to the characterizing part of claim 2, in addition to feeding the plastic material into the gap, a supporting part is fed to the latter, which supports the support between the printing device and the plastic material in such a way that the plastic material is at least once again separable at least when the hooking means are shaped Incoming connection with the support part, on the one hand, very high supporting forces can be realized during the shaping by the adhesive connection and, on the other hand, the adhesive force can be used in order to be able to reliably and specifically form the interlocking means with their undercuts from the mold cavities of the molding device. The forced detachment from the molding device ensures that the interlocking means do not remain in the mold cavities, the latter being able to severely disrupt the production process. It is also ensured in this way that the 'counterforces introduced via the support part do not inadvertently result in the hooking means being torn off. since these can be formed from the cavities with gentle forces. Accordingly, the use of the support part is also useful in all those applications where undercuts are made in the molding tool when shaping the hooking means, in order, for example, to be able to form a conventional hook shape or the like. In such cases it is also possible to make the carrier material extremely thick, so that very small hooking means are then placed in one piece on a thick carrier part, which can be useful for certain application modalities.

In a further preferred form of the method according to the invention, a plastic film, preferably a polyester film, polypropylene film or polyamide film, is used as the support part. However, a thin metal foil, for example an aluminum foil, can also be used as the support part. Especially when using metal foils, the support part can be used again and again in a closed circuit, so that no waste arises, which on the one hand benefits the environment and on the other hand contributes to lowering the manufacturing costs for the system.

Any shape can be produced as a hooking means, such as hooking heads, engagement hooks, mushrooms or preforms on hooking means such as stem material, the free head ends of which are formed into hooking heads in a subsequent shaping process, for example a calendering process.

It has also proven to be particularly advantageous to use a printing or a forming roller with the opposite direction of rotation as the printing and shaping device, the rollers in question being heated for the shaping process. If the introduced plastic material for the shaping is a thermoplastic polyurethane material, on the one hand a favorable connection is achieved with the support part for the shaping process, which, however, can also be easily separated again after the shaping in order to obtain the elastic adhesive closure part.

The method according to the invention is explained in more detail below using an exemplary embodiment. The only figure shows, in principle and not to scale, the device for carrying out the method.

The figure shows a shaping device, generally designated 10, in the form of a shaping roller on which. a sieve 12 is drawn up, which can for example consist of nickel. The screen 12 of the shaping roller 10 has cavities 14 on its entire outer circumference which have been etched in a manner known per se by means of a galvanic process. These cavities 14 can have a substantially cylindrical basic shape; however, any other shape can also be etched. The galvanic treatment of the cavities 14 gives them a characteristic shape. The elevations in question can be used to produce the hooking means of an adhesive closure part 18, designated as a whole by 16, in a single operation. For this purpose, a flowable plastic material is supplied in a manner known per se in a plastic or liquid state by means of a feed device 20 in the form of an extruder to a gap 22 between the forming roll 10 and a printing device in the form of a printing roll 24.

The shaping roller 10 and the pressure roller 24 are driven in the opposite direction of rotation, so that the plastic released from the extruder 20 into the gap 22 between the rollers 10 and 24 and thus in the assignable cavities 14 can flow. The plastic located in the gap 22 forms a carrier 26 to which the hooking means 16 are connected in one piece. At the same time, the distance between the two rollers 10 and 24 determines the width of the gap 22 and thus the thickness of the carrier 26. The hooking means 16 themselves are formed by the plastic flowing into the open cavities 14 of the screen 12 of the shaping roller 10, whereby in Interaction with the elevations in the cavities 14 caused by the galvanic etching as described above, which have a stem 28 formed by the cavity 14, at the end facing away from the carrier 26 an all-round edge in the form of a thickening or a hooking head 30 is formed. The respective interlocking head 30 is suitable for interlocking with interlocking means of a further adhesive closure part, not shown in more detail, for example in the form of a fake. The relevant manufacturing process for adhesive fastener parts is known and is described in detail, for example, in DE 196 46 318 A1.

The manufacturing process described above is also particularly suitable for the production of so-called micro-adhesive material. in which the interlocking means 16 have an extremely small geometric size. In the present embodiment, a thermoplastic polyurethane material serves as the plastic material for producing the hooking means 16 including the carrier 26. In order to be able to reduce the thickness of the carrier 26 in the manufacture of the hooking means 16 in detail, in addition to the feeding of the plastic material into the gap 22, the feeding of a support part 32 is provided which is fed between the pressure roller 24 and the plastic material of the carrier 26, the latter Supports. Without the supporting part 32 in question, the contact pressure of the pressure rollers 24 would be sufficient if the support 26 were made sufficiently thin sufficient, which can be at a line pressure of more than 1 t, to damage the carrier 26. By means of the mentioned support part 32, on the other hand, the relevant contact pressure forces are absorbed uniformly and it is surprising that in this way the carrier 26 can be exempted from harmful forces and made extremely thin.

A plastic film, preferably a polyester film, polypropylene film or polyamide film, can be used as the support part 32. A polyester film is to be used in the present exemplary embodiment. The support part 32 can also consist of a thin metal foil, for example an aluminum foil or the like. In the embodiment shown, the support part 32 is continuously moved via deflection rollers 34 in a closed circuit, the direction of rotation of the deflection rollers 34 being represented by arrows. If the support part 32 is designed as a polyester film, it is more practical, according to practical tests, to dispose of the polyester film after its use and to insert new film material at the location of the upper feed of the plastic material.

In addition to the aforementioned deflection rollers 34, a take-off roller 36 is also provided, with the same direction of rotation as the pressure roller 24, the take-off roller 36 serving to remove the hooking means 16 from the cavities 14 of the forming roller 10. In order to make the head shapes of the interlocking heads 30 flat, in particular in order to broaden their edge, it can be provided that the actual shaping process is followed by a calendering process in which two calender rolls 38 under pressure with the support part 32 removed on the rear side of the carrier 26 and act on the top of the interlocking heads 30. After the relevant calendering process the fastener part 18 can then be wound up on shipping rolls for further transport in the usual and not shown manner. After the removal of the support part 32 in the form of the polyester film, provision can also be made for the adhesive closure part 18 to be removed immediately and subjected to the calendering process mentioned in another work station (not shown). If 12 modern conical sieve structures are used instead of the simple structure of a sieve, calendering can also be dispensed with entirely if necessary.

In order to ensure that the connection between the support part 32 and the support 26 in the shaping gap 22 runs smoothly and the subsequent removal of the support part 32 from the support 26 in the region of the lower deflection roller 34, as shown, both the molding roll 10 and the pressure roller 24 are heated. It has proven to be advantageous to drive the pressure roller 24 in a temperature range up to 130 ° C., preferably in the range around 100 ° C., whereas the shaping roller 10 is preferably operated in a temperature range between 20 ° C. and 150 ° C. in a temperature range around 40 ° C. Furthermore, it has proven to be advantageous to select film material for the support part 32, for example in the form of a polyester film whose Shore A hardness according to DIN 53.504 is in a range from 80 to 89, preferably 85. The stretch elasticity of the carrier film as support part 32 can be in the range from 0 to 5% for a polyester film, whereas the thermoplastic polyurethane material used for the adhesive fastener part 18 has a stretch elasticity between 15 to 89%; both values measured according to Vickers at 1 mm thick test specimen and room temperature.

_: The mentioned carrier 26 and the support part 32 can have a band structure, but can also be designed as a sheet-like film body his. The extensible or elastic support 26 can be made very thin. In the case of an elastic property, the hooking means 16 can be moved away from one another under the action of force, whereby the carrier 26 expands further and, when the force 26 of the carrier 26 is removed, the hooking means 16 automatically returns to their original position due to its inherent elasticity. In this respect, a fully elastic adhesive closure part 18 is realized with which a large number of practical applications can be realized.

If a polyester film is used as the support part 32, it is also possible to produce a separable connection between the support part 32 and the support 26 during the shaping. The relevant adhesive or adhesive connection then ensures that the subsequent removal process, in which the interlocking means 16 are molded out of the cavities 14 of the molding device 10, can take place without hindrance, even if undercuts in the head material of the interlocking means 16 were undermined by parts of the molding device 10 are. The latter also allows a higher speed of the production process. Furthermore, it is possible in this way to implement small-sized head parts or hooking means 16 with very thick supports 26 (not shown).

The polyester film preferably remains as a support part 32 on the carrier 26 in the subsequent calendering process 38, in order to influence the head design of the hooking means 16 in a favorable manner. Then the support part 32 can then be separated from the carrier 26 and disposed of or returned to the molding device for a new processing step.

Claims

Patent claims

1. A method for producing an adhesive closure part (18) with a multiplicity of hooking means (16) formed in one piece with a carrier (26), in which a plastic material in a flowable state for

Formation of the carrier (26) is fed to a gap (22) between a pressure device (24) and a shaping device (10) which is provided with cavities (14) for shaping the respective hooking means (16), characterized in that in addition to the feed of the plastic material in the gap (22) this a support member (32) is fed, the ial between the pressure device (24) and the plastic material supports the support (26) such that it is so thin in the shape of the hooking means (16) is that the carrier (26) is provided with a predeterminable extensibility or elasticity with a suitable plastic material.

2. A method for producing an adhesive closure part (18) with a plurality of interlocking means (16) formed in one piece with a carrier (26), in which a plastic material in a flowable state to form the carrier (26) has a gap (22) between a printing device ( 24) and a molding device (10) which is provided with cavities (14) for shaping the respective interlocking means (16), characterized in that, in addition to feeding the plastic material into the gap (22), a supporting part (32) is fed to the latter that supports the support (26) between the printing device (24) and the plastic material in such a way that the plastic material at times forms a releasable connection with the support part (32) at least when the hooking means (16) are shaped.

3. The method according to claim 1 or 2, characterized in that a plastic film, preferably a polyester film, polypropylene film or polyamide film is used as the support part (32).

4. The method according to claim 1 or 2, characterized in that a thin metal foil, for example an aluminum foil, is used as the support part (32).

5. The method according to any one of claims 1 to 4, characterized in that the film-like support member (32) is reused in the manner of a closed circuit.

6. The method according to any one of claims 1 to 5, characterized in that hooking heads (30), engagement hooks, mushrooms or preforms such as stems (28) are formed as the hooking means (16) during the shaping process.

7. The method according to any one of claims 1 to 6, characterized in that the shaping process is followed by a calendering process (38) which preferably acts on the head design of the hooking means (16).

8. The method according to any one of claims 1 to 7, characterized in that the plastic material introduced is a thermoplastic polyurethane material. Method according to one of Claims 1 to 8, characterized in that a pressure or molding roll with opposite direction of rotation is used as the pressure (10) and molding device (12), and in that the rolls (10, 12) in question are heated for the molding process become.