Component and method for its production

Abstract

Component (1) formed from at least one fiber layer (1.1) and at least one foam layer (1.2), wherein the fiber layer (1.1) is a semi-finished product made of a pre-formed and thermally pre-treated fiber fleece made of a weldable thermoplastic, to which a foam material of the foam layer (1.2) is applied on one of the surface sides in such a way that this foam material partially penetrates into the fiber fleece of the semi-finished product and the component (1) has a thickness (D) of less than 8 mm and a density of greater than 90 kg / m 3 has.

Description

[0001] The invention relates to a method for producing a component, in particular a support component for a seat. Furthermore, the invention relates to a method for producing the component.

[0002] A cushioning element and a method for producing a cushioning element are known from the prior art according to EP 2 933 136 A1 of the applicant. The cushioning element is formed from a fiber composite material with a three-dimensionally stochastically oriented fiber material. The fiber composite material comprises at least one weldable thermoplastic.

[0003] A fiber composite material for a support component is also known from DE 30 22 017 C2.

[0004] DE 10 2008 035 610 A1 describes a seat cushion element for use in a motor vehicle and a method for producing a seat cushion element, wherein the seat cushion element has a foam region and wherein the cushion element has a fiber region with a fiber material, wherein the fiber material in the fiber region is foamed through by the foam of the foam region.

[0005] Furthermore, DE 10 2010 040 082 A1 discloses a padding and a method for producing the padding. The padding comprises a core part with at least one reinforcing element.

[0006] The object of the present invention is to provide a method for producing a component which is improved compared to the prior art and an improved component produced by means of the method.

[0007] The object is achieved according to the invention by a method for producing a component and by such a component.

[0008] In a method for producing a component, according to the invention, a fiber layer, in particular a fiber fleece made of a three-dimensionally stochastically oriented fiber material, is thermally pretreated in such a way that the porosity of the fiber layer can be adjusted. The manufactured component has a thickness of less than 8 mm, in particular equal to or less than 7 mm, and a density of greater than 90 kg / m 3 In particular, the fiber layer, in particular a prefabricated or preformed fiber fleece, has a density of greater than 90 kg / m 3 on.

[0009] A further development stipulates that the manufactured component has a density of greater than 100 kg / m 3 , especially in a range of 100 kg / m 3 up to 300 kg / m 3 , has.

[0010] Density is, in particular, the mass density, which is a quotient of the mass m of the component and its volume. In one possible measurement, a sample is cut from the component and determined using a conventional measurement method, for example, by measuring the displaced fluid volume. Alternatively, the density can also be determined theoretically by specifying the volume of the component and the mass, for example, the amount of fiber and foam material added.

[0011] In particular, such an adjustable density and the resulting adjustable porosity of the fiber layer, especially of the fiber fleece, allows the penetration of a subsequently applied foam material to be controlled. This also allows a component with an adjustable density of greater than 90 kg / m 3 and can therefore be produced with a specified strength and hardness.

[0012] The fiber material is preformed and pretreated. The fiber material can be made from one or more different materials, for example polyester, polyethylene, polypropylene, and / or polyurethane. It can be made from random fibers, in particular from recycled or non-recycled natural and / or synthetic fibers. Alternatively, it can be a woven or nonwoven fleece. Due to the thermal treatment of the fiber material, this is also called a thermal fleece. This is advantageously a three-dimensional, stochastically oriented fiber material. Plastic fibers are made from a thermoplastic, in particular from a modified and weldable thermoplastic. For example, the plastic fibers are made from polyethylene terephthalate (PET), polyester, or a synthetic polymer, in particular from polylactide (PLA). A mixture of fibers made from different plastics is also possible.A binder, in particular a thermosetting binder, is provided to bond the fiber material. The binder is, for example, a thermosetting adhesive, in particular a halogenated hydrocarbon, such as chloroprene rubber, and / or a polyurethane-based thermosetting binder, such as a PU or PUR adhesive.

[0013] In a further embodiment, the preformed fiber material, for example a nonwoven fabric, in particular a plastic nonwoven fabric, is coated. For example, the preformed fiber material is additionally provided with a plastic layer. Polyethylene (PE) is particularly suitable as a material for a plastic layer. The coating material is particularly thin and is applied, for example, in the form of a plastic film to the preformed fiber material. This enables improved air regulation. Furthermore, a coated preformed fiber material, for example a coated nonwoven fabric, is optimized and less susceptible to mechanical stress, in particular damage, pressure marks, and breakage.

[0014] The fiber material can, for example, be applied to one surface side of a molding tool. For thermal treatment of the fiber material, one embodiment can thermally treat it once or multiple times in the molding tool itself. Alternatively, the fiber material can be prefabricated and thermally treated before being inserted into the molding tool. The thermal treatment softens the fiber material, with the thermal treatment being controlled such that a predetermined porosity can be achieved. The fiber material is preformed into a semi-finished product with a predetermined porosity, in particular surface porosity.

[0015] A foam material, particularly polyurethane, is then introduced into the mold. The mold may already be closed. Alternatively, the foam material, such as liquid polyurethane, can be introduced into the mold while it is open, and the mold is then closed. For example, the preformed fiber fleece is placed on the lid of a mold, and the foam material is introduced into the base of the mold. The lid is then closed, allowing the liquid foam material to penetrate the fiber fleece.

[0016] When using a coated preformed nonwoven fabric, less liquid foam material gets into the nonwoven fabric because the coating acts as a barrier.

[0017] As a component, a component for a vehicle is produced by means of the method, expediently a vehicle interior component, in particular a component for a vehicle seat, for example a backrest support or a seat cushion support for a vehicle seat.

[0018] The invention further relates to a component according to the invention, produced in particular by means of the method, which comprises a fiber layer, in particular a fiber fleece, made of a three-dimensionally stochastically oriented fiber material with partially penetrated foam material and, in the finished state, has a density in a range of greater than 90 g / l (=kg / m 3 ), in particular greater than 100 g / l or in a range from 100 g / l to 300 g / l, and a thickness of less than 8 mm.

[0019] Advantageously, the fiber layer forms a front side of the component, for example, a backrest support or a seat cushion support, and the foam layer forms a back side, or vice versa. Preferably, the fiber layer forms the back side of the component. The seat surface of a seat cushion or a seat back can then be formed on the front side of the component to form the vehicle seat, for example, by arranging a cushioning material and a seat cover, or by arranging only a seat cover.

[0020] The fiber layer, in particular the nonwoven fabric, advantageously has a constant basis weight, so that the manufactured components can also be formed with a substantially constant basis weight. The nonwoven fabric can optionally be prefabricated and preformed into a semi-finished product. Furthermore, the preformed nonwoven fabric can be provided with a coating, in particular a plastic coating, for example, a polyethylene layer or a polyethylene film.

[0021] For preforming the nonwoven fabric and / or for thermal treatment, in particular thermal post-treatment of a preformed nonwoven fabric, a heated plate can be provided, onto which the nonwoven fabric or the preformed nonwoven fabric is placed in order to heat it and then insert it into the forming tool. Alternatively or in addition to the heated plate, other heating devices for heating the nonwoven fabric are also possible, for example, heating by infrared radiation from one or more infrared radiators. This means that the nonwoven fabric must be heated by at least one heating device in order to soften it in the heated state such that a predetermined porosity can be achieved, at least in the surface area of the nonwoven fabric.

[0022] Advantageously, liquid plastic material, in particular a liquid, foamable plastic, is applied to the fiber fleece arranged in the mold, and the component is formed, pressed, or injection-molded using the mold. This requires only a single production station in which the entire process can be carried out.

[0023] The fiber fleece replaces in particular a conventional wool batting used in the prior art, which does not have the described advantages of the preform fleece, in particular the stiffness. Therefore, for example, applying the fiber material to the wool batting outside the molding tool and then transporting it to the molding tool would not be possible or would only be possible with considerable additional effort. The thermally treated fiber fleece, which has the adjustable porosity and density described above, is made, for example, from polyester fibers and / or other plastic fibers, in particular melt-bonded fibers. A design from wool batting / shredded wool batting mixed with such plastic fibers, in particular melt-bonded fibers is also possible. This means:the fiber layer or the fiber fleece is designed in such a way that it can be transformed or formed when heated to a predetermined softening temperature and stiffened again by subsequent cooling in such a way that a predetermined porosity and / or a predetermined density can be set at least in the surface region of the fiber layer or the fiber fleece.

[0024] The component, made of nonwoven fabric with penetrated foam material, exhibits high rigidity and, at the same time, improved contour formation as well as high strength and resistance after compression molding or injection molding.

[0025] The nonwoven fabric used, in particular rolls or sheets, comprises, for example, a polyester material and / or other melt-bonded fibers, i.e., it expediently comprises fibers made of plastic, in particular thermoplastic. Furthermore, it may also comprise, for example, natural fibers or other fibers. The fiber materials already mentioned above are suitable for forming the nonwoven fabric.

[0026] The component is formed in the mold by bonding the fibers of the fiber layer or nonwoven fabric to the liquid foam material and pressing them together using the mold. The bonding is achieved using the binder and / or by heating the fiber material in the mold and / or before insertion into the mold.

[0027] In one possible embodiment, one or more inserts made of plastic, for example made of polyethylene terephthalate (PET), can additionally be provided. Such inserts, for example to enable seat ventilation, are expediently applied to the fiber layer or the fiber fleece and connected to the fiber layer or the fiber fleece with a so-called adhesive web and / or by hot riveting using a so-called hot riveting unit and / or by cold stamping. The fiber material is then introduced into the mold, in particular laid, and the component is formed in the mold by introducing the foam material and subsequently pressing the fiber layer and foam layer, so that the insert or inserts are integrated into the component, in particular partially or largely completely surrounded, in particular cast, by the foam material.

[0028] Due to the resulting partially different thickness of the applied and pressed fiber material in the area of the insert(s) compared to a component without inserts, a so-called cassette tool is expediently used as the molding tool, whereby the shape of the molding tool can be changed using one or more cassettes. Therefore, multiple molding tools are not required, but the molding tool can be adapted to different shapes. This embodiment of the component is also lighter than the prior art, can be easily dried after formation in the cassette tool, and has a higher grade of purity, since, for example, the inserts, the fiber material, and the foam material are made of the same plastic, for example, polyester or polyethylene terephthalate (PET), whereas the prior art uses a wool fleece, i.e.another material that reduces the purity of the variety.

[0029] Embodiments of the invention are explained in more detail with reference to the drawings. In the drawings: Fig. 1 schematically shows an embodiment of a component designed as a seat back, Fig. 2 schematically shows an embodiment of a component designed as a seat part, and Fig. 3A, Fig. 3B schematically enlarged partial views of a section through a component designed as a seat part in various embodiments, Fig. 4 schematically shows a process flow of a method for producing a component.

[0030] Corresponding parts are provided with the same reference numerals in all figures.

[0031] The Fig. 1 and Fig. 2 each show a plan view of a component 1 according to the invention. Fig. 1 shows a component 1 designed as a backrest cushion part and Fig. 2 a component 1 of a vehicle seat not shown in detail, designed as a seat part cushion.

[0032] The component 1, which is designed in particular as a cushioning element for a vehicle seat, is formed, as an alternative to a known fleece or cushion, in particular a wool-wool fleece or natural fiber cushion, from a fiber layer 1.1 made of a fiber material that is provided with a foam layer 1.2 on at least one surface side. The foam layer 1.2 can be applied completely to the fiber layer 1.1 on at least one surface side. Alternatively, it can also be applied only partially.

[0033] The component 1 according to the invention comprises at least one fiber layer 1.1, wherein the foam material of the foam layer 1.2 has partially or, according to a non-inventive embodiment, completely penetrated, in particular, into the surface area of the fiber layer 1.1. In the finished state, the component 1 has a density in a range of greater than 90 g / l (= kg / m 3 ), in particular greater than 100 g / l or in a range from 100 g / l to 300 g / l.

[0034] The component 1 has a high density, in particular a density in the range of 300 kg / m, when the foam material fully penetrates into the fiber layer 1.1. 3 If only a partial penetration of the foam material into the fiber layer 1.1 occurs, the component 1 has a density of at least greater than 90 kg / m 3 , especially greater than 100 kg / m 3 on.

[0035] For this purpose, the component 1 is formed from a fiber layer 1.1 that is thermally treated in such a way that porosity can be adjusted at least in the surface area of the fiber layer 1.1. The fiber layer 1.1, in particular a fiber fleece, can be prefabricated as a roll or sheet and can be thermally pretreated at least once or multiple times.

[0036] In addition, the fiber layer 1.1 can also be preformed.

[0037] The fiber layer 1.1, in particular a nonwoven fabric, is formed from a three-dimensionally stochastically oriented fiber material. For example, the fiber layer 1.1 has a surface porosity that is exposed by thermal treatment, allowing the foam material of the foam layer 1.2 to penetrate into the fiber layer 1.1 to a predetermined depth.

[0038] The fiber material can, for example, comprise at least one modified and weldable thermoplastic formed from a three-dimensional stochastically oriented polyethylene terephthalate (PET) or polyester or from a synthetic polymer, in particular from polylactide (PLA for short), which is additionally bound, for example, by means of a thermosetting binder or a halogenated hydrocarbon, in particular chloroprene rubber, and / or by means of a polyurethane- or PUR-based binder.

[0039] Fig. Figure 3A shows an enlarged sectional view of a component 1 in a possible embodiment. Due to the improved strength and hardness of the component 1 as a result of the foam material of the foam layer 1.2 penetrating the fiber layer 1.1, the fiber layer 1.1 can have a smaller thickness than conventional cushioning elements for a vehicle seat. The cushioning element in Fig. The component 1 shown in Fig. 3 preferably has a thickness D of less than 8 mm, in particular less than 7 mm.

[0040] In particular, the fiber layer 1.1 has a thickness D1 of 0.5 mm to 5 mm. The foam layer 1.2 has a thickness D2 of less than 6 mm. The thickness D2 of the foam layer 1.2 also depends on the degree of penetration of the foam material into the fiber layer 1.1. If the foam material of the foam layer 1.2 completely penetrates the fiber layer 1.1, the foam layer 1.2 has a small thickness D2, for example, of 1 mm to 4 mm.

[0041] Advantageously, the fiber layer 1.1 forms a back side of the component 1 and the foam layer 1.2 forms a front side of the vehicle seat.

[0042] To form the vehicle seat, the seat surface of a seat cushion or a seat back can then be formed on the front side of the component 1, for example by arranging a padding material and a seat cover or by arranging only a seat cover.

[0043] The fiber layer 1.1 advantageously has a constant basis weight, so that the manufactured component 1 is also formed with a substantially constant basis weight.

[0044] The foam layer 1.2 is made, in particular, of polyurethane. Alternatively, another suitable foam material may be used.

[0045] Fig. 3B shows an alternative embodiment of a component 1 with an enlarged cross-sectional view of the component 1. The nonwoven fabric 1.1 is provided with a coating 1.3. The coating 1.3 is particularly thin, in particular formed as a film on the nonwoven fabric 1.1. For example, the coating 1.3 is made of plastic, in particular polyethylene. The coating 1.3 improves the strength and hardness of the component 1, in particular of the fiber layer 1.1.

[0046] The coating 1.3 is designed such that the foam material of the foam layer 1.2 can at least partially penetrate the fiber layer 1.1. The combination of the coating 1.3 on the fiber layer 1.1 and the foam material of the foam layer 1.2 that has partially penetrated the fiber layer 1.1 further increases the strength and results in the component 1 having a significantly lower thickness than conventional upholstery elements for a vehicle seat.

[0047] The upholstery element in Fig. 3A and Fig. The component 1 shown in Figure 3B has a thickness D of less than 8 mm, in particular less than 7 mm.

[0048] A manufacturing process is schematically simplified as follows: Fig.4. In a first method step S1, to produce the component 1, the fiber layer 1.1 is thermally treated, for example by applying heat T, such that a predetermined porosity P1.1, in particular a predetermined surface porosity on at least one surface side of the fiber layer 1.1, can be achieved. In this case, the fiber layer 1.1 can be thermally treated differently in certain regions, resulting in fiber layer regions of varying strength. For example, regions with inserts 2 to 4 can be thermally treated more intensively to achieve greater strength than other regions.

[0049] In a second step S2, the fiber layer 1.1 is provided with a foam material, in particular polyurethane, at least on one surface side, preferably on the side with the predetermined porosity P1.1. The foam material penetrates into the surface of the fiber layer 1.1 due to its permeable and open surface porosity. The predetermined and adjustable porosity P1.1 of the fiber layer 1.1 is characterized by an adjustable number of pores, an adjustable pore size, and / or an adjustable pore depth as a result of the thermal treatment.

[0050] The foam material does not penetrate the fiber layer 1.1. The fiber layer 1.1 is produced with a porosity P1.1 such that the foam material only penetrates the surface and does not penetrate through it.

[0051] The component 1 is finally formed by closing the mold and pressing, in particular hot pressing, the two layers, in particular the fiber layer 1.1 and the foam layer 1.2. Such a component 1 has a small thickness of less than 8 mm, in particular less than 7 mm. Furthermore, such a component 1 has a high density of greater than 90 g / l, in particular from 100 g / l to 300 g / l.

[0052] The fiber layer 1.1 can be thermally treated in the mold itself. For example, the fiber material can be introduced into the mold, in particular, scattered, and thermally treated. Subsequently, the foam material of the foam layer 1.2 is introduced into the mold. Due to the given porosity P1.1, the foam material penetrates the fiber layer 1.1, so that the foam does not foam or only partially foams. The mold is then closed, and the component 1 is formed, for example, by hot pressing.

[0053] Alternatively, the fiber layer 1.1 can be prefabricated and thus be in solid form, for example, as a fiber fleece in rolls or mats. The fiber fleece can be introduced into the mold and thermally treated there. Alternatively, the fiber fleece can be heat-pretreated outside the mold.

[0054] Due to its high resilience, the foam material of foam layer 1.2 introduced into the mold fills any remaining free space between fiber layer 1.1 and a mold half of the mold corresponding to the shape of the back side without any further action. The foam material thus fills the free volume of the mold and penetrates the fiber layer 1.1 already inserted or introduced into the mold. Subsequently, both layers 1.1 and 1.2 are pressed together and bonded. As a result, component 1 exhibits good rigidity, strength, and resilience in its final manufactured state, while preferably still being soft.

[0055] After component 1, for example, a backrest or seat part, has been formed, the component 1 is dried. Additionally, the component 1 can be punched or pinched. Pinching is advantageously performed during drying, while punching is advantageously performed after drying, with component 1, for example, either pinched or punched, or, for example, pinched and punched in certain areas. Drying is advantageously performed in a closed mold. Drying is advantageously achieved by supplying air to the component 1.

[0056] In addition, the component 1 can be provided with at least one or more inserts 2 to 4. For example, fastening means 2 and nonwoven inserts 3 to 4 are integrated into the component 1 as inserts 2 to 4. The component 1 and the insert(s) 2 to 4 are connected to one another by means of suitable connections, such as so-called adhesive web or hot riveting units.

[0057] Compared to the conventional manufacturing process, this results in improved high strength and density of greater than 100 g / l while maintaining a low thickness D of less than 8 mm for component 1. List of reference symbols 1 component 1.1 Fiber layer 1.2 Foam layer 1.3 Coating 2 to 4 inserts D, D1, D2 thickness S1, S2 process steps P1.1 Porosity T Heat supply

Claims

[1] Component (1) formed from at least one fiber layer (1.1) and at least one foam layer (1.2), wherein the fiber layer (1.1) is a semi-finished product made of a pre-formed and thermally pre-treated fiber fleece made of a weldable thermoplastic, to which a foam material of the foam layer (1.2) is applied on one of the surface sides in such a way that this foam material partially penetrates into the fiber fleece of the semi-finished product and the component (1) has a thickness (D) of less than 8 mm and a density of greater than 90 kg / m 3 has. [2] Component (1) according to claim 1, wherein the component (1) and / or the at least one fiber layer (1.1) has a density of greater than 100 kg / m 3 , especially in a range of 100 kg / m 3 up to 300 kg / m 3 , has. [3] Component (1) according to one of the preceding claims, wherein the fiber layer (1.1) is additionally provided with a coating (1.3). [4] Component (1) according to one of the preceding claims, wherein the fiber layer (1.1) is formed at least from fibers of a polyester material. [5] Component (1) according to one of the preceding claims, wherein the at least one foam layer (1.2) is formed at least from polyurethane on the fiber layer (1.1). [6] Component (1) according to one of the preceding claims, wherein the fiber layer (1.1) and the foam layer (1.2) are integrally connected to one another. [7] Component (1) according to one of the preceding claims, wherein the fiber layer (1.1) forms a rear side of the component (1). [8] Component (1) according to one of the preceding claims, wherein the foam layer (1.2) forms a front side of the component (1). [9] Method for producing a component (1) formed from at least one fiber layer (1.1) and one foam layer (1.2), wherein - the fiber layer (1.1) is preformed as a fiber fleece made of fibers of a thermoplastic to form a semi-finished product and is thermally pretreated by applying heat in such a way that a predetermined surface porosity is set on at least one surface side of the fiber layer, and wherein a foam material of the foam layer (1.2) is subsequently applied to the at least one surface side with the predetermined surface porosity of the preformed and thermally pretreated fiber fleece of the semi-finished product, wherein the foam material partially penetrates into the fiber layer (1.1) and foams out, and wherein a component (1) is produced by pressing to a thickness (D) of less than 8 mm and a density of greater than 90 kg / m 3 is finally formed.

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