WO2006066601A1 - Thermoformable support element - Google Patents

Abstract

The invention relates to a thermoformable support element which comprises at least one layer, produced from a spunbonded nonwoven having a dry weight per unit area of 100 - 1500 g/m<SUP>2</SUP>. The invention also relates to support elements produced from said material, preferably for use as molded parts for vehicles.

Description

 description

Thermoform bares carrier part

Technical area

The invention relates to a thermoformable carrier part comprising at least one layer of a spunbonded nonwoven, which preferably consists at least partially of contoured fibers, of hollow fibers or mixtures thereof, wherein the layer has a basis weight dry of 100-1500 g / m ² at a thickness of 1-100 mm, as well as thermoformed carrier therefrom, in particular for molded parts of a vehicle.

State of the art

As materials for thermoformed carrier parts, such as. As headliner in vehicles, thermoset composite materials are preferably used from several materials. It forms the core of such

Composite is a saturated or coated with liquid isocyanates polyurethane foam, which is solidified by crosslinking during deformation. In order to achieve the necessary mechanical properties, in particular the necessary high rigidity, for such carrier parts, the isocyanate-impregnated or coated polyurethane foam is used before the Thermoforming, inter alia, covered on both sides with glass fibers. Nonwovens and / or films and decorative layers are applied over the glass fibers. Such thermoformed carrier, such as. As headliner, prepare because of the glass fibers contained therein problems in the disposal and show only a limited acoustic effectiveness, which is not sufficient for vehicles. Corresponding constructions are known, for example, from DE-A-1 974 468 2, DE-A-1 975 710 2 or DE-A-1 981 315 2.

Carrier parts, in which this problem is largely avoided, are known from DE-U-2 990 409 1. These carrier parts are made of staple fiber nonwovens based on thermoplastic polyester fibers, which have a high proportion of so-called bicomponent binder fibers in the nonwoven fabric to achieve the necessary mechanical properties, in particular a high stiffness and thermal resistance. To achieve the necessary stiffness basis weights of more than 1500 g / m ² to 1800 g / m ^{2 are} necessary, which is not acceptable in view of the desired weight reduction of vehicles and the associated lower fuel consumption.

Presentation of the invention

It was therefore an object of the present invention to provide a thermoformable support member comprising a carrier formed therefrom, preferably a molding for vehicles, excellent acoustic effectiveness, easy disposal and excellent mechanical properties, in particular excellent rigidity, at a relatively low basis weight guaranteed. This object is achieved by providing the thermoformable support part according to the invention comprising at least one layer of a spunbonded nonwoven fabric, wherein the layer has a basis weight dry of 100-1500 g / m ² at a thickness of 1-100 mm.

Preferably, the layer of spunbonded nonwoven fabric of the thermoformable carrier part has a weight per unit area of 300 to 1200 g / m ² at a thickness of 2 to 30 mm, particularly preferably a basis weight of 400 to 1000 g / m ² at a thickness of 3 to 15 mm.

The thermoformable carrier part according to the invention preferably has no glass fibers.

The spunbonded fabrics used are preferably obtained from the corresponding polymer melt in line by spinning, drawing, laying and solidification. As solidification of the spunbonded nonwovens, the well-known in the art methods such as thermofusion and possibly needling come into question.

The fibers of the spunbonded fabric are at least partially solid or hollow fibers. At least part of the fibers may have a round or contoured cross-section.

It is also possible that all the fibers of the spunbond fabric are solid, but preferably at least a portion of the fibers is hollow. It is also preferred that at least a part of the fibers has a contoured cross-section.

The contoured fibers preferably have a multilobal, polygonal, preferably triangular, star-shaped, flat, oval, T-shaped, Y-shaped shaped or H-shaped cross-section. Preferably, the hollow fibers have a round cross-section.

The fibers of the spunbonded nonwoven fabric are preferably made of synthetic, particularly preferably thermoplastic polymers selected from the

Group comprising polyesters, polyamides, viscose, polyolefins, polyacrylonitriles and mixtures of at least two polymers of the same or a different type. More preferably, the fibers of the spunbonded nonwoven fabric are made of polyester.

The spunbonded fabric also includes binder fibers. As binder fibers mono- and / or bicomponent binder fibers can be used. The bicomponent binder fibers may preferably have a core / sheath or side by side construction.

The layer or layers of spunbonded nonwoven fabric are preferably solidified by thermofusion with the aid of mono- or bicomponent binder fibers and optionally by needle punching.

The needling of the spunbond fabric is carried out by known methods.

The binding fibers mentioned can, like the other fibers of the spunbonded fabric, have a round or contoured cross section, be solid or hollow, but a round cross section is preferred. The contoured cross sections correspond to the cross sections given for the remaining fibers of the spunbonded fabric. Preferably, the monocomponent binder fibers have a contoured cross-section. Preferably, they are hollow. The bicomponent binder fibers are preferably solid. Preferably, they have a contoured cross-section. The binder fibers consist of at least one synthetic thermoplastic polymer selected from the group comprising polyesters, polyamides, viscose, polyolefins and polyacrylonitriles, wherein the bicomponent binder fibers are composed of two thermoplastic polymers with different melting points. At least one outboard part of a binder fiber is composed of a thermoplastic polymer which melts more deeply by at least 15 ⁰ C as the polymers from which the fibers of the spunbonded nonwoven fabric are constructed. When monocomponent binder fibers are used, these fibers are entirely composed of the aforementioned lower melting thermoplastic polymers, while when using bicomponent binder fibers, the outer-member polymer, preferably the sheath, of the bicomponent binder fibers has a melting point which is around at least 15 ⁰ C is lower than the melting point of the polymer of the remaining part, preferably of the core, the

Bicomponent binding fibers or the remaining fibers of the spunbonded nonwoven fabric. Preferably, one part, preferably the core, of the bicomponent binder fiber consists of the same polymer as the other fibers of the spunbonded nonwoven, more preferably the same polyester. The monocomponent binder fiber or an outer part, preferably the sheath, the bicomponent binder fiber preferably consists of the same type of polymer of the thermoplastic polymer from which the remaining fibers of the spunbonded fabric have been produced, wherein, as already stated, such a polymer or Copolymer has a melting point at least 15 ⁰ C lower than the melting point of the polymer were made from the fibers of the spunbonded nonwoven fabric. Particularly preferably, the monocomponent binder fibers or an outer part, preferably the sheath, the bicomponent binder fiber of a further polyester or copolyester, if the fibers of the spunbonded fabric or the remaining part, preferably the core, the bicomponent Bindefasem consist of preferably identical polyesters.

The layer or layers of the spunbonded fabric can consist of up to 100% by weight of bicomponent binder fibers.

The layer or layers of the spunbonded fabric preferably have 20 to 80% by weight, particularly preferably 40 to 60% by weight, based on the total weight of the respective spunbonded nonwoven layer, bicomponent binder fibers or preferably 1-50% by weight, preferably 1 to 25% by weight, particularly preferably 5 to 20% by weight, based on the total weight of the spun-bonded nonwoven layer of the monocomponent binder fiber.

The fibers of the spunbonded fabric including the monocomponent binder fibers or the bicomponent binder fibers have a titer in the range of 2 to 20 dtex, preferably 5 to 15 dtex.

The layer or layers of spunbonded nonwoven fabric of the thermoformable carrier part according to the invention may also be constructed in multiple layers to adjust the mechanical properties of the carrier formed therefrom. The individual layers of this layer preferably consist of identical spunbonded nonwovens. But it is also possible to use for each layer a spunbonded fabric of identical staple fibers and different binder fibers, provided that the above-mentioned conditions for the binder fibers are met. This also applies to a multi-layered build that out

Spunbonded fabrics with different staple fibers and identical binder fibers or a multi-layer structure of spunbonded nonwovens, each with different staple fibers and each different binder fibers. It is also possible, the individual layers of the layer of spunbonded nonwoven fabric using an adhesive based on a polyolefin, a polyamide, copolyamide, a polyester, a copolyester, an optionally crosslinkable polyurethane and / or a crosslinkable epoxy resin, or by hydroentanglement and optionally by needling to connect with each other. For this purpose, the adhesive can be used as a powder, adhesive fleece (M-Webs), spray adhesive, individual adhesive dots or in the form of an adhesive film.

Advantageously, the thermoformable carrier part according to the invention also has a multi-layered construction beyond. In addition to the layer of spunbonded nonwoven fabric, which may optionally be constructed in multiple layers, at least one surface of the support part may be covered with a textile covering layer.

Preferably, the textile cover layer consists of a nonwoven fabric. As the nonwoven fabric, a spunbonded fabric, a wet nonwoven fabric or a dry laid nonwoven fabric based on the above-mentioned fibers, preferably polyester fibers, may be used. Nonwovens with a low intrinsic weight and with a low extensibility are preferably used.

These cover layers of nonwoven fabric layers preferably have a thickness between 0.05 and 1 mm and have a weight per unit area of 20 to 250, preferably between 50 and 200 and very particularly preferably between 50 and 150 g / m ² . The nonwoven fabrics used can be solidified by any known consolidation methods such as needling, thermofusion, calendering, chemical bonding or hydroentanglement or a combination of these methods. Very particular preference is given to a spun-bonded nonwoven fabric or a dry-laid nonwoven fabric, if appropriate may contain up to 50-80 wt .-% of natural fibers and is solidified by water jet used.

As natural fibers are z. As wood fibers, flax, hemp, kenaf, jute or sisal fibers. The concomitant use of natural fibers makes it possible to further increase the stiffness of the carriers formed from the carrier parts according to the invention. This is necessary if the thermoformed carrier as a molded part such. As a headliner, used in vehicles, the complete attachments, such as sun visors, mirrors, lighting systems and cable strands must carry freely.

The second, opposite surface of the layer of spunbonded nonwoven fabric of the thermoformable support part according to the invention may also be covered with a further textile layer, which is preferably identical to the first cover layer described above. The basis weight dry of the preferably used nonwoven fabric preferably corresponds to the values given above.

Overall, the total weight per unit area dry of the thermoformable carrier part according to the invention is 100-1500, preferably 300-1200, particularly preferably 400-1000 g / m ² .

In addition, a visible decorative material can still be applied on the visible side of the above-described overall construction of the thermoformable carrier part according to the invention, so that after thermoforming of the carrier part the desired finished molded part, preferably a molded part of a vehicle, is obtained.

The bonding of the individual layers can be carried out with the aid of the abovementioned adhesives, after the layers have been preceded if necessary have already been loosely connected by a needling together. For this purpose, these adhesives can be used as a powder, adhesive fleece (M-Webs), spray adhesive, individual adhesive dots or in the form of an adhesive film. The permanent connection of the individual layers is preferably achieved by the subsequent thermoforming of the carrier part according to the invention, which is covered with the covering layers and optionally the decorative layer, in particular by the thermofusion of the binding fibers.

A further subject of the present invention is therefore also a process for the preparation of a thermoformable support member by in line, solid and / or hollow fibers with a round or contoured cross-section and corresponding mono- or bicomponent binder fibers according to a corresponding melt spinning process using suitable nozzle devices prepares, deposits to a spunbonded fabric and solidified by thermofusion using the existing mono- or bicomponent binder fibers and optionally needlepunching, optionally with the above-mentioned other textile layers, and optionally decorated and singulated into a carrier part.

The thermoforming process for producing a thermoformed carrier from the thermoformable carrier part according to the invention can take place with the aid of a so-called cold or hot pressing process. According to the hot process, the thermoformable carrier part according to the invention, which is optionally provided with the cover layers and the decorative layer, placed in a preheated press and deformed under pressure to the desired shape. According to the cold process, a corresponding thermoformable support member is heated prior to pressing by means of IR-beam, hot air or contact heating to the temperature necessary for the deformation and deformed in a cold press under pressure to the desired shape. Another object of the present invention are therefore also a thermoformed carrier with a dry area of 100-1500 g / m ² and with a flexural strength of> 1000 N mm. These carriers are obtained by thermoforming from the thermoformable carrier part according to the invention. Preferably, they are used as a molded part of a vehicle.

Most preferably, such a thermoformed support is a molded part of a vehicle, preferably in the form of a vehicle headliner, a pillar and / or door panel, a floor panel, a parcel shelf, a trunk lining, at least part of an engine compartment lining, such as a Bonnetliner, an insert mat and / or a front wall insulation.

The supports of the invention are characterized by an excellent bending strength characterized by a maximum bending force of> 35 N measured according to EN 310 with the test parameters: sample size 90 x 75 mm, test speed: 20 mm / min, open width: LS = 80 mm, off.

Embodiment of the invention

The object of the invention will now be explained in more detail with reference to some examples.

Example 1 :

A layer of spunbonded nonwoven having a basis weight of 500 g / m ² consisting of 80 wt .-% polyester hollow fibers having a fiber denier of about 6 dtex and 20 wt .-% monocomponent binder fibers having a fiber denier of about 6 dtex of copolyester having a melting point of 225 ⁰ C, which after the

Fiber deposit slightly vorvernadelt and was thermally prefixed at 200 ⁰ C, is with a second layer of identical spunbonded nonwoven fabric having a basis weight of 250 g / m ² using a propylene copolymer spunbonded with a basis weight of 30 g / m ² at a temperature of 130 ⁰ C laminated. The total basis weight of the carrier part is 780 g / m ² .

The support member is heated by means of flow heating so that the temperature is 200 ⁰ C and pressed in a cold press at 80 ⁰ C to a headliner. Obtained is a molding, which in the three-point bending test as indicated above, according to EN 310 has a maximum bending force of 35.9 N at a flexural strength of 1100 Nmm. The acoustic behavior was determined in the impedance tube according to DIN EN ISO 105341-1 and compared with a headliner made of PU / glass fibers (prior art) in Tab.

Example 2:

Two layers of spunbonded nonwoven having a basis weight of 500 g / m ² each consisting of 40 wt .-% polyester fibers with a fiber denier of about 6 dtex and 60 wt .-% bicomponent binder fibers with a fiber denier of about 6 dtex of a polyester core (83 wt .-% of the fiber weight) with a copolyester sheath (17 wt .-% of the fiber weight) with a melting point of 225 ° C, which were easily vorvernadelt after fiber deposition and thermally pre-fixed at 200 ⁰ C, are using a propylene - Laminated spunbonded nonwoven fabric having a basis weight of 30 g / m ² at a temperature of 130 ⁰ C. The total basis weight of the carrier part is 1030 g / m ² .

The support member is heated by means of flow heating so that the temperature is 200 ⁰ C and pressed in a cold press at 80 ⁰ C to a headliner. Obtained is a molding that in the three-point bending test as indicated above, according to EN 310 a maximum Bending force of 67.4 N with a bending stiffness of 1236 Nmm. The acoustic behavior was determined in the impedance tube according to DIN EN ISO 105341-1 and compared with a headliner made of PU / glass fibers (prior art) in Tab.

Table 1 :

Determination of the sound absorption coefficient according to DIN EN ISO 105341-1

Claims

claims A thermoformable support member comprising at least one layer of a spunbonded nonwoven having a dry basis weight of 100 - 1500 g / m ² at a thickness of 1 - 100 mm. 2. Thermoformable support member according to claim 1, characterized in that ddaassss ddaass FFlläächengewicht 300 - 1200 g / m ² at a thickness of 2 - 30 mm. 3. Thermoformable carrier part according to claim 1 or 2, characterized ggeekkeennnnzzeeiicchhnneett ,, ddaassss ddaass FFllääichengewicht 400 - 1000 g / m ² at a thickness of 3 - 15 mm. 4. Thermoformable carrier part according to one of claims 1 to 3, characterized in that at least a part of the fibers of the spunbond fabric consists of solid or hollow fibers with a round or contoured cross-section. 5. Thermoformable carrier part according to one of claims 1 to 4, characterized in that the spunbonded comprises mono- or bicomponent binder fibers. 6. Thermoformable carrier part according to one of claims 1 to 5, characterized in that at least part of the monocomponent binder fibers is solid or hollow and the fibers have a round or contoured cross-section. 7. Thermoformable carrier part according to one of claims 5 to 6, characterized in that the proportion of monocomponent binder fibers. 1 to 50% by weight, preferably 1 to 25% by weight, particularly preferably 5 to 20% by weight, based on the total weight of the spunbonded nonwoven layer. 8. Thermoformable carrier part according to one of claims 1 to 5, characterized in that at least part of the bicomponent binding fibers is solid or hollow and the fibers have a round or contoured cross-section. 9. Thermoformable carrier part according to one of claims 5 to 8, characterized in that the bicomponent binder fibers side by side or sheath / core binder fibers. 10. Thermoplastic carrier part according to claim 8 or 9, characterized in that the spunbonded fabric of up to 100 wt.% Bicomponent binder fibers. 11. Thermoplastic carrier part according to claim 10, characterized in that the proportion of bicomponent binder fibers 20 to 80 wt.%, Preferably 40 to 60 wt.%, Based on the Total weight of the spunbonded fabric is. 12. Thermoformable carrier part according to one of claims 1 to 11, characterized in that the contoured fibers or binding fibers have a multilobal, polygonal, preferably triangular, star-shaped, flat, oval, T-shaped, Y-shaped or H-shaped cross-section. 13. Thermoformable carrier part according to one of claims 1 to 12, characterized in that the spunbonded nonwoven fabric by thermofusion is solidified by means of the mono- or bicomponent binder fibers and optionally by needle punching. 14. Thermoformable carrier part according to one of claims 1 to 13, characterized in that the fibers and binding fibers of Spunbonded nonwoven fabric made of synthetic, thermoplastic polymers, preferably of at least one polyester, at least one polyamide, at least one viscose, at least one polyolefin and / or at least one polyacrylonitrile or at least two of said polymers of different types. 15. Thermoformable carrier part according to claim 14, characterized in that the fibers and a part, preferably the core, of the bicomponent binding fibers of the same polymer and at least one outer part, preferably the jacket, the Bicomponent binder fibers or monocomponent binder fibers from a corresponding polymers having a lower by at least 15 ⁰ C melting point than the melting point of the polymer of the remaining part, preferably the core of the bicomponent binder fibers or other fibers are constructed. Thermoformable support member according to claim 15, characterized in that the fibers and at least a part, preferably the core, of the bicomponent fibers of the same polyester and an outer part, preferably the sheath, the bicomponent Binder fiber or the monocomponent binder fiber of a polyester or copolyester having a melting point at least 15 ° C lower than the melting point of the polymer of the remaining part, preferably the core, the bicomponent binder fibers or the other fibers are constructed. 17. Thermoformable carrier part according to one of claims 1 to 13, characterized in that all fibers have a titer in the range of 2 to 20 dtex, preferably 5 to 15 dtex. 18. Thermoformable carrier part according to one of claims 1 to 17, characterized in that the layer of spunbonded nonwoven fabric is constructed in multiple layers. 19. Thermoplastic carrier part according to claim 18, characterized in that the individual layers of the layer of spunbonded nonwoven fabric by means of an adhesive based on a polyolefin, polyamide, copolyamide, a polyester, a copolyester, an optionally crosslinkable polyurethane and / or a crosslinkable epoxy resin, by Needling and / or by Hydroentanglement are connected together. 20. Thermoformable support member according to one of claims 1 to 19, characterized in that at least one surface of the thermoformable support member is covered with a textile covering layer, preferably based on a nonwoven fabric. 21. The thermoformable carrier part according to claim 20, wherein the nonwoven fabric of the cover layer or cover layers is a spunbonded nonwoven fabric, a wet nonwoven fabric or a dry laid nonwoven fabric, preferably a spunbond fabric or a dry laid nonwoven fabric made of polyester fibers and optionally 50 to 80 wt% natural fibers , the water jet was solidified. 22. Thermoformable carrier part according to claim 20 or 21, characterized in that over at least one cover layer, a visible decorative material is applied. 23. Process for the in-line production of a thermoformable carrier part according to one of claims 1 to 22, characterized in that fibers and binder fibers are produced by the melt spinning process using suitable nozzle devices, laid down to the nonwoven fabric and solidified by thermofusion with the aid of binder fibers and possibly needlepunching, optionally covers and optionally decorated, and isolated to the support part. 24. Thermoformed carrier of a carrier part according to one of claims 1 to 22. 25. Thermoformed carrier according to claim 24, having a basis weight dry of 100 to 1500 g / m ² and with a bending stiffness of> 1.000 N x mm. 26. Thermoformed carrier according to claim 24 or 25 as a molded part of a vehicle. 27. A thermoformed carrier according to claim 26 in the form of a vehicle headliner, a pillar and / or door trim, a floor assembly, a parcel shelf, a trunk lining, a An inlay mat, at least part of an engine compartment lining, such as a Bonnetliners, and / or a bulkhead insulation is. 28. A method for producing a thermoformed carrier according to any one of claims 24 to 27, characterized in that the after the thermoformable carrier part produced in line method according to claim 22, after or during a heating phase to the carrier pressed molding.