DE102008031573B4 - Stretchable fleece with ladder structures - Google Patents

Abstract

Layer comprising a fleece (5), which is made up of fibers, and at least one metallic conductor track (3), wherein the conductor track (3) is firmly attached to the fibers of the fleece (5), the conductor track (3) against the Fleece (5) is electrically insulated with an insulator (4) arranged between the conductor track (3) and the fibers and the fibers of the fleece (5) and the conductor track (3) are at least partially embedded in the insulator (4), characterized by extensibility, wherein the fleece (5) and the conductor track (3) can jointly expand without being destroyed, and wherein the conductor track (3) has a meandering structure, preferably a wave structure.

Description

Technical area

The invention relates to a layer comprising a nonwoven, which is composed of fibers, and at least one metallic conductor track, wherein the conductor track is firmly connected to the fibers of the nonwoven, wherein the conductor track against the nonwoven with the arrangement of an insulator between the conductor track and the fibers is electrically isolated and wherein the fibers of the nonwoven and the conductor track are at least partially embedded in the insulator.

State of the art

Layers of the type mentioned are already known from the prior art. In particular, the shows US 5 277 734 A a layer on which a conductor track is applied by means of a transfer adhesive film.

In the generic composite according to DE 196 34 016 A1 For example, for curing an insulating resin composition, thermal curing or UV curing is proposed.

The DE 35 08 888 A1 discloses a layer of conductive tracks formed as non-metallic carbon and silicon carbide fibers.

The US 5,888,627 A shows a hard and firm layer of fleece, which is impregnated with a thermosetting resin.

In the DE 103 35 693 B3 describes a resin-impregnated glass fiber fabric whose resin hardens.

In the WO 02/31214 A1 discloses a layer which has been subjected to a plasma treatment and germinated with target atoms.

It is furthermore known from the prior art to structure layers of conductive material by means of chemicals and to create printed conductors.

However, in these methods, it is disadvantageous that the substrates to which the printed conductors are firmly connected are subjected to the chemicals.

In particular, chemicals used in structuring processes of conductive materials can be detrimental to health, damage the substrate or remain in the substrate. Nonwovens tend in particular to soak. Often, aftertreatment does not lead to the desired purity of the substrate. The breathability, porosity and tensile strength of the substrate remain negatively affected.

Although printed conductors can also be applied to substrates without the said chemicals being used, for example, an adhesive layer used in this case is often insufficient to permanently bond the printed conductors to a nonwoven under mechanical load.

In particular, in the case of twisting, stretching, folding or bending of the layer, the conductor tracks can detach from the substrate. Such layers are not suitable for applications in which they are subjected to vibrations, strains or vibrations.

Presentation of the invention

The invention is therefore based on the object to design a layer of the type mentioned and further, that this shows a firm connection of the metallic interconnects to the fibers, the situation has health largely harmless substances.

According to the invention the above object is achieved with the features of claim 1.

Thereafter, the aforementioned layer is characterized by an extensibility, wherein the web and the conductor are stretched together destructive and together and wherein the conductor has a meander structure, preferably a wave structure.

According to the invention, it has been recognized that an insulator which can embed both the fibers of the nonwoven and the conductive tracks can be at least partially introduced into the nonwoven fabric by lamination processes using heat and pressure. It has also been recognized that this makes possible a firm connection of metallic conductor tracks to a nonwoven. Finally, it has been recognized that the use of an insulator, which can at least partially integrate the conductor tracks, enables the production of particularly fine metallic conductor tracks. In a lamination process, the use of chemicals is not mandatory. Therefore, health-critical chemicals in the situation according to the invention do not come into contact with the fleece.

Against this background, the situation is characterized by a distensibility, wherein the fleece and the conductor can be stretched together non-destructive. The layer has a sufficient extensibility, since the insulator on the one hand fixes the conductor tracks and on the other hand, the fibers of the Vlieses embeds. Through this specific embodiment, the layer can be used for the production of products that are in contact with the human body. In particular, it is conceivable to use the situation for the production of fitness clothing, shoe soles, compression stockings, wound dressings or ECG accessories. The extensibility of the situation also allows the situation also apply to thermally deformable documents, such as those used for the manufacture of components for the automotive interior. In concrete terms, it is conceivable to use the situation for manufacturing a console. The situation has proven surprisingly elastic, strong and stable for use in shoe soles in which a permanent load on the situation is given. Next, the situation can be surprisingly well, without damaging the tracks, be thermoformed. This allows use of the situation in the automotive interior in various geometric configurations.

A conductor track has a meander structure, preferably a wave structure. By forming a meander structure, the track can be stretched in length without tearing. The formation of a meander structure complements combinatorial with the connection of the conductor tracks through the insulator to the fibers of a nonwoven. Since the insulator is elastic and the fibers are largely loose and disordered in the fleece, stretching of the layer is possible without the conductor tracks being torn or damaged. Consequently, the object mentioned above is achieved.

Against this background, it is conceivable that a conductor track is made of copper. Copper is particularly suitable as a conductive material due to its excellent electrical conductivity.

The trace could be enclosed by the insulator or multiple insulators. Through this specific embodiment, the layer can be brought into contact with the human body, without this being affected by flowing currents. It is conceivable that the side of the layer, which has the fleece, is in contact with the human body.

The insulator could be designed as an at least partially hardened insulation paste. An insulating paste can be applied by screen printing on a substrate.

The isolation paste could include polyurethane and methylcellulose. An insulating paste of this composition is particularly suitable for the production of a layer, since these insulation paste undergoes an excellent bond with the fibers of a nonwoven and the metallic conductor tracks when heated. Furthermore, an insulating paste of this embodiment surprisingly shows a particular elasticity after cooling. The insulation paste can in particular according to the embodiments of the DE 10 2007 042 253 A1 , but without conductive fillers.

A sheet of the type described above could be made by a process comprising the following steps:
Providing an at least one-sided adhesive film,
Applying a layer of conductive material to the adhesive side of the film,
Patterning the conductive material to create traces;
Coating the printed conductors with at least one insulating paste,
Applying a fleece to the insulation paste and
Remove the foil.

Such a method makes it possible to produce a layer which is characterized by a particular elasticity and extensibility with fixed connection of the conductor tracks to the nonwoven.

As a film, a self-adhesive thermo-release film could be used, which loses its adhesive power when heated. The use of such a film allows a brief heating of the thermo-release film to about 155 ° C, which loses its adhesive power. The film can then be easily removed from the finished layer without tearing the webs connected to the web from the web or pulled out.

Against this background, the layer of conductive material could be configured as copper foil and the application to the adhesive film by lamination. This concrete embodiment ensures that an electrically very good conductive material enters a tight bond with the film almost wrinkle-free.

The patterning of the conductive material could be done by etching. An etching process is particularly well suited for producing very fine printed conductors. In particular, it is possible by means of an etching process to produce meander-shaped structures, such as spirals, zig-zag structures or undulating structures.

The coating of the conductor tracks with insulating paste could be carried out such that initially a first layer of insulating paste is applied by printing and subsequent lamination and then a second layer of insulating paste is applied by printing on the first layer. Through this specific embodiment is First, ensure that the first layer of insulation paste forms a firm bond with the conductor tracks. However, printing can cause pinholes in the first layer of insulation paste. By printing with a second layer of insulation paste, the pinholes are closed.

The fleece could be applied to the insulation paste by lamination. This concrete embodiment ensures that the nonwoven forms a very strong bond with the insulation paste. By lamination, the polyurethane in the insulation paste bonds particularly tightly to the fibers of the nonwoven, so that they are at least partially enclosed by the insulating paste. Of the more valuable causes the lamination, that the insulating paste enters into a particularly strong bond with the tracks and this also at least partially encloses.

The lamination could be done by heating and compressing the individual layers or foils. It is actually conceivable that the lamination takes place at a temperature of 125 ° C and at a pressure of 5.8 bar.

The film could be briefly heated and then removed from the tracks. By heating the film to about 155 ° C this loses its self-adhesive properties and can be removed from the tracks, without being pulled out of the fleece or torn out.

The conductor tracks released by the film could be printed with insulation paste. By this step, the tracks could be completely surrounded with insulating paste.

The situation described here could also be produced by a method comprising the following steps:
Providing an at least one-sided adhesive film,
Coating the film with at least one insulating paste,
Applying a layer of conductive material to the insulating paste,
Patterning the conductive material to create traces;
Coating the printed conductors with at least one insulating paste,
Applying a fleece to the insulation paste and
Remove the foil.

By this method, a layer with excellent elongation properties can be generated, since the insulating paste, the conductor tracks completely and the fibers of the nonwoven at least partially encloses.

Against this background, it is conceivable that a polyethylene terephthalate adhesive film with pure acrylate adhesive is used as the film. The pure acrylate adhesive could be applied in very small quantities. This makes it possible to easily remove the film from the finished layer without the fleece is separated from the tracks.

The coating of the film with insulating paste could be carried out such that first a first layer of insulating paste is applied by printing and subsequent lamination and then a second layer of insulating paste is applied by printing on the first layer. This specific embodiment ensures that pinholes that occur in the first layer due to the printing are closed by the second layer.

The layer of conductive material could be configured as a copper foil and the application to the insulating paste could be done by lamination.

The lamination allows a particularly firm connection of the layer of conductive material on the insulation paste.

The patterning of the conductive material could be done by etching. Etching processes allow the production of very fine meander structures.

The coating of the conductive material or of the conductor tracks provided with insulating paste could be carried out such that initially a first layer of insulating paste is applied by printing and subsequent lamination and then a second layer of insulating paste is applied by printing on the first layer. By this method, pinholes introduced by printing in the first layer can be closed by the second layer.

The fleece could be applied to the insulation paste by lamination. The lamination allows a firm connection of the fleece on the insulation paste.

Against this background, the lamination could be carried out under heating and pressure loads. To avoid repetition, reference should be made at this point to the comments on the first method already described.

There are now various possibilities, the teaching of the present invention in an advantageous To design and develop ways. For this purpose, on the one hand to the subordinate claims, on the other hand, to refer to the following explanation of preferred embodiments of the inventive situation with reference to the drawings.

In conjunction with the explanation of the preferred embodiments with reference to the drawings, generally preferred embodiments and developments of the teaching are explained.

Brief description of the drawing

In the drawing show

1 individual process steps of a first method for producing a layer,

2 individual process steps for producing a layer according to a second method, and

3 four schematic examples of meander-shaped structures of the conductor tracks.

Embodiment of the invention

1 schematically shows a method for producing a sheet comprising the following steps:
Providing an at least one-sided adhesive film 1 , which is designed as a self-adhesive thermo-release film that loses its adhesive power when heated. Concretely, a film of the type Rexpan RP 70 E5 Teltec is used.

On the slide 1 becomes a layer of conductive material 2 , namely a copper foil, applied. The layer of conductive material 2 is on the adhesive side of the film 1 applied by lamination. The lamination is carried out at a temperature of 40 ° C at a pressure of 2 bar and at a speed of 0.4 m / min. A roll lamination is performed.

This is followed by patterning of the layer of conductive material 2 under creation of tracks 3 , Structuring is carried out using a UV laser using a Bluetape Minitron 1008 R etching mask. The patterning is further carried out by etching. An alkaline etching solution used at 45 ° C is used.

Following this, the tracks will 3 with at least one insulation paste 4 coated. The coating of the tracks 3 with insulation paste 4 takes place such that initially a first layer of insulating paste 4 is applied by printing and subsequent lamination and then a second layer of insulating paste 4 by printing on the first layer of insulation paste 4 is applied. The lamination is carried out at a temperature of 125 ° C and a pressure of 5.8 bar at a belt speed of 2.5 m / min. It is used a so-called Bandlaminiergerät.

After that, the fleece becomes 5 by laminating on the insulating paste 4 applied. At the fleece 5 it is a fleece of the type Evolon 100 or XO 90 of Freudenberg Nonwovens KG, Weinheim, DE. Lamination takes place with heating and pressure loading. The isolation paste 4 combines firmly with the fibers of the fleece 5 ,

After that, the film becomes 1 briefly heated to about 155 ° C. Heating the foil 1 At about 155 ° C leads to the reduction of their adhesive power, leaving the film 1 after cooling to room temperature easily from the tracks 3 can be removed.

After removing the film 1 from the tracks 3 become the tracks 3 on the slide 1 facing side with insulation paste 4 printed.

By the method described above creates a layer with a nonwoven 5 which is composed of fibers. The layer has at least one metallic conductor track 3 on. The conductor track 3 is firmly attached to the fibers of the fleece 5 tethered, with the conductor track 3 against the fleece 5 under arrangement of an insulator 4 between the track 3 and the fibers are electrically isolated. Some fibers of the fleece 5 are at least partially in the insulator 4 embedded. The tracks 3 are completely in the insulator 4 embedded.

The resulting layer is characterized by the use of a nonwoven type XO 90 by an excellent extensibility, wherein the nonwoven 5 and the tracks 3 together can be stretched non-destructive.

The tracks 3 are made of copper and of the insulator 4 , namely the insulation paste 4 , enclosed. The isolation paste 4 has polyurethane and methylcellulose.

For the production of the situation just described, a method according to 2 be used. The method according to 2 includes the following steps:
It is an at least one-sided adhesive film 1a provided. At the slide 1a it is a film of the type Duplocoll 6001 B from Lohmann. At the slide 1a it is a polyethylene terephthalate adhesive film with pure acrylate adhesive.

The foil 1a comes with at least one insulation paste 4 coated. The isolation paste 4 is applied to the film by a screen printing process 1a applied. On it is the isolation paste 4 along with the foil 1a laminated. For lamination, a tape laminator is used. The lamination process is carried out at a temperature of 125 ° C and a pressure of 5.8 bar. The lamination process takes about 27 seconds, with a belt speed of 2.5 m / min. Coating the foil 1a with insulation paste 4 takes place such that initially a first layer of insulating paste 4 is applied by printing and subsequent lamination and then a second layer of insulating paste 4 by printing on the first layer of insulation paste 4 is applied. Through the second layer of insulation paste 4 Pinholes are closed in the first layer of insulation paste caused by the printing.

This is followed by a layer of conductive material 2 namely, a copper foil on the insulating paste 4 laminated. The lamination of the layer of conductive material 2 is carried out by a belt laminator, which performs the lamination at 125 ° C and 5.8 bar in a time of about 27 seconds at a belt speed of 2.5 m / min.

This is followed by patterning of the layer of conductive material 2 , namely the copper foil, by etching, a so-called subtractive method. Here are tracks 3 created. The etching is carried out using a UV laser and an etching mask of the type Bluetape Minitron 1008 R. For the etching of the copper foil, an alkaline etching solution at a temperature of 45 ° C is used.

Then the resulting tracks are 3 with at least one insulation paste 4 coated. Coating the layer of conductive material 2 or the conductor tracks 3 with insulation paste 4 takes place such that initially a first layer of insulating paste 4 is applied by printing and subsequent lamination and then a second layer of insulating paste 4 by printing on the first layer of insulation paste 4 is applied. Through the second layer of insulation paste 4 should pinholes in the first layer of insulation paste 4 be closed by printing in the first layer of insulation paste 4 were introduced.

Following this will be a fleece 5 on the insulation paste 4 applied. At the fleece 5 it is a fleece of the type Evolon 100 or XO 90 of Freudenberg Nonwovens KG, Weinheim, DE. The fleece 5 is by lamination on the insulation paste 4 applied. Lamination takes place with heating and pressure loading. The isolation paste 4 combines firmly with the fibers of the fleece 5 , After that, the fleece becomes 5 with the tracks 3 that are in the isolation paste 4 are included, from the foil 1a deducted.

Performing the methods described above results in a layer of fine metallic interconnects 3 , where the fleece 5 not in contact with chemicals. This gives a breathable and elastic layer with good conductivity.

The isolation paste 4 in the embodiments described here is according to embodiment 1 of the DE 10 2007 042 253 A1 , but made without conductive fillers.

3 shows four schematic examples of meander-shaped structures of the conductor tracks 3 , In 3a) and b) wavy structures are shown. In 3c) and d) so-called horseshoe-shaped structures are shown. 3d) shows three fine adjacent tracks 3 , which together follow the horseshoe-shaped structure.

With regard to further advantageous embodiments and developments of the teaching of the invention reference is made on the one hand to the general part of the description and on the other hand to the appended claims.

Finally, it should be emphasized that the previously selected embodiments are only for the purpose of discussing the teaching of the invention, but not limit these to these embodiments.

Claims (5)

Layer comprising a fleece ( 5 ), which is composed of fibers, and at least one metallic conductor track ( 3 ), wherein the conductor track ( 3 ) to the fibers of the nonwoven ( 5 ) is firmly connected, wherein the conductor track ( 3 ) against the fleece ( 5 ) with an insulator ( 4 ) between the track ( 3 ) and the fibers is electrically isolated and wherein the fibers of the nonwoven ( 5 ) and the track ( 3 ) at least partially into the insulator ( 4 ), characterized by a stretchability, wherein the fleece ( 5 ) and the track ( 3 ) are non-destructively extensible and wherein the conductor track ( 3 ) has a meander structure, preferably a wave structure. Layer according to claim 1, characterized in that the conductor track ( 3 ) is made of copper. Layer according to claim 1 or 2, characterized in that the conductor track ( 3 ) from the insulator ( 4 ) or more insulators is enclosed. Layer according to one of claims 1 to 3, characterized in that the insulator ( 4 ) as insulation paste ( 4 ) is trained. Layer according to claim 4, characterized in that the insulating paste ( 4 ) Polyurethane and methylcellulose.

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