METHOD AND DEVICE FOR BACKFOAMING AN UPPER MATERIAL

Description

[0001] The invention relates to a method for backfoaming an outer material.

[0002] Like flame-laminated or adhesive-laminated outer materials, back-foamed outer materials are used, for example, as decorative and / or functional materials, particularly as interior materials in the visible area of ​​a motor vehicle. During the production of such a material, the foam material and the outer material are first produced separately and then joined together in a subsequent joining step. Such a process is known from EP 3 085 606 A1.

[0003] US 2006 / 0079589 A1 discloses the preamble of claim 1; it shows a polyurethane foam layer and a method for a multi-layer composite with the polyurethane foam layer.

[0004] DE 19 23 531 A discloses a method and a device for leveling a foam-forming reaction mixture continuously applied to a moving substrate.

[0005] The invention is based on the object of simplifying the production of such a composite material and, in particular, of making the production economical.

[0006] The object is achieved by the features of claim 1. The core of the invention lies in the discovery that the foaming of a liquid foam material and the bonding of the foam material with a face material to form a composite material can be combined in one, particularly single-stage, manufacturing process. According to the invention, direct backfoaming of the face material is thus possible in a single-stage in-situ process. A multi-stage process with separate manufacturing processes and a subsequent joining step of semi-finished products is unnecessary. The manufacturing process according to the invention reduces process steps and is cost-effective. The manufacturing process according to the invention is economical.

[0007] It is essential that the foam material is first partially foamed before the foam layer is bonded to the outer material. It has been recognized that this counteracts foaming through the outer material. The outer material has a comparatively open surface, so that a mechanical and / or chemical bond with the foam material is favored. The outer material is in particular a woven fabric made of warp threads and weft threads. In particular, the warp thread density is less than 50 threads per cm, in particular less than 40 threads per cm and in particular a maximum of 35 threads per cm. In particular, the warp thread density is at least 10 threads per cm, in particular at least 20 threads per cm and in particular at least 25 threads per cm. The weft thread density is in particular a maximum of 25 threads per cm, in particular a maximum of 20 threads per cm and in particular a maximum of 17 threads per cm.The weft thread density is, in particular, at least five threads per cm, in particular at least seven threads per cm, and in particular at least eight threads per cm. Alternatively, the outer material can also be designed with a relatively closed surface, in particular as a closed film and in particular as artificial leather.

[0008] In the process according to the invention, a reactive foam material in the form of a liquid is first provided as a foam layer with an initial height. The foam material is, in particular, a mixture of polyol and isocyanate, although additional additives can be added.

[0009] Aggregates can be, for example, additives, in particular catalysts, which are present in particular in a proportion of 1 pphp based on polyol. pphp stands for "parts per hundred parts polyol per weight." The water content is in particular between 0 and 1.75 pphp, in particular 0.75 pphp. The quantitative ratio of polyol to isocyanate is in particular 2.0:1.0. This quantitative ratio is in particular in a range from 1.0 to 3.0:1.0, in particular from 1.5 to 2.5:1.0. The foam material is in particular provided at room temperature and in particular without additional heat input. For the subsequent foaming process, it can be advantageous if the foam material is heated, at least slightly, and in particular to a maximum temperature of at most 50°C, in particular at most 45°C, in particular at most 40°C, in particular at most 35°C, and in particular at most 30°C.

[0010] The initial height of the foam layer corresponds to the applied thickness of the liquid. The height direction during foaming of the foam material corresponds to the final thickness direction of the foam layer and, in particular, of the resulting composite material.

[0011] One finding underlying the invention is that the foam layer to be bonded to the outer material is produced from the reactive foam material during the process according to the invention and is immediately processed. It is therefore unnecessary for pre-foamed material to be provided in the form of a foam layer as a semi-finished product and bonded to the outer material. According to the invention, it was found that the production of the foam layer from the foam material and the bonding to the outer material can be combined in one and the same process. The process according to the invention is functionally integrated and avoids the storage and transport of semi-finished products. The process is efficient.

[0012] In particular, it was discovered that the reactive foam material initiates a polyaddition reaction, which is what forms the actual foam layer, especially polyurethane, in the process according to the invention. This avoids the need to prepare a finished foam layer and subsequently re-thermally activate it, i.e., melt it. The process according to the invention is inexpensive. The energy input is reduced.

[0013] In particular, the components present in the foam material mixture, especially polyol and isocyanate, are present as liquids. This simplifies handling in the process according to the invention.

[0014] It was also recognized that separate adhesives for bonding the foam material to the outer material are unnecessary because the foam material itself, which is only produced during the process, has sufficient tackiness. One reason for this is that only partial foaming occurs. The tackiness of the incompletely cured foam material is sufficient.

[0015] It is essential that at the end of the process according to the invention the foam material has completely reacted to form a foam layer and is, in particular, mechanically resilient, i.e., foamed.

[0016] The foam material used is in particular unfoamed polyurethane foam material, which is particularly liquid.

[0017] The foam layer is, in particular, a flat structure with a length and a width that are each larger, in particular significantly larger, than the initial height. In particular, the length and / or width are at least ten times larger, in particular at least fifty times larger, in particular at least one hundred times larger than the initial height.

[0018] The foam material is foamed. The foaming takes place at least partially, in particular to at least 50%, in particular to at least 70%, in particular to at least 80%, in particular to at least 90% and in particular completely. The foaming takes place, in particular initially, incompletely but evenly. Incomplete means that only a proportion of the reactive foam material has reacted. Incompletely foamed foam material therefore still has a proportion of reactive, in particular liquid, foam material. Evenly means that the foam layer is foamed over its entire surface up to a first height, whereby the first height is greater than the initial height. In particular, the height of the foam material, i.e. the thickness of the foam layer, is constantly increased by the foaming. In particular, the height of the foam layer is distributed homogeneously over the entire surface of the foam layer.

[0019] Because the foam material is only partially foamed, an upper contact surface of the foam material is sticky, thus exhibiting adhesive material properties. The foam itself is mechanically and / or chemically unstable in the partially foamed state and, in particular, cannot withstand mechanical loads. It is advantageous if the incomplete foaming is completed when the foam layer, in particular, reaches a first height limit. Particularly in a continuous process, a control system is advantageous in which the foam layer reaches the first height limit after the incomplete foaming is completed.

[0020] An optional first height limiter ensures that the first height is not exceeded during partial foaming of the foam layer. The height expansion of the foam layer is limited by the first height limiter during foaming. The contact surface of the foam layer, which in particular faces the first height limiter, is optionally wetted with a reaction aid. The reaction aid is in particular a wetting agent. Water is used as a wetting agent in particular. Other wetting agents are also possible, which accelerate the foaming of polyurethane foam material in particular.

[0021] It is particularly advantageous that the reaction aid is applied to the foam layer before the outer material is applied to the foam layer. This allows the foaming process to be initiated earlier and, in particular, more effectively. This promotes the bonding of the foam layer to the outer material. In particular, the reaction aid is added directly as a component of the liquid foam layer.

[0022] The first height limitation is particularly unnecessary if the outer material has sufficient density. It has been found that the outer material has sufficient density to be bonded directly to a contact surface of the foam layer. In particular, if the outer material is sufficiently dense, the use of the upper contact material is unnecessary. A top material is considered sufficiently dense if, as a woven fabric composed of warp and weft threads, it has a density of at least 15 weft threads per cm and at least 23 warp threads per cm. Such a dense top material essentially serves as a film-like carrier material.

[0023] Surprisingly, it was found that the density of the outer material is sufficient to prevent it from being saturated by the foam material. According to the invention, the foam material therefore only reacts to the extent that it has a viscous consistency, in particular is so viscous that it does not become saturated with the outer material, i.e. this is prevented. Contact between the foam material and the outer material occurs in particular when the mixture reaches a so-called gel point, or shortly before. The gel point is defined as the point in time at which the mixture no longer deforms or flows. The gel point of the foam material is in particular in a range from 1.0 min to 5 min. In particular, the gel point for the foam material can vary depending on the composition and in particular depending on the ratio of polyol to isocyanate.

[0024] Alternatively, it is possible to allow the foam material to foam for a defined reaction period and to place it under the upper contact material until the foam material is almost solid.

[0025] In this case, the height can be defined via the material application, i.e. the addition of the foam material, the removal element in the form of a squeegee, and the second height limitation in particular.

[0026] In particular, the wetting agent is applied directly to the contact surface of the foam layer by means of the first height limitation, in particular by the contact of the foam layer with a contact foil arranged at the first height limitation. In particular, the wetting of the foam layer by means of the contact foil is straightforward. The wetting agent represents a processing aid. The contact surface of the foam layer is impregnated with the wetting agent. In particular, the degree of impregnation can be specifically adjusted. By applying the wetting agent, the reactions taking place during foaming of the foam material can be specifically influenced and, in particular, accelerated. It has been found that the reactive foam material, which in particular comprises a mixture of polyol and isocyanate with water, reacts more quickly through the addition of the reaction aid, in particular in the form of water.

[0027] The outer material is arranged on the contact surface of the foam layer and connected thereto. The height expansion of the composite material is limited by a second height limiter. The composite material is pressed, in particular, against the contact surface of the foam layer by means of the second height limiter. The foam layer is joined to the outer material to form the composite material, in particular by applying pressure by means of the second height limiter. In particular, a second height of the foam layer in the composite material is less than or equal to the first height. In particular, the second height limiter defines a gap with a gap dimension that corresponds to the second height.

[0028] The joining process, i.e., the bonding of the outer material to the foam layer, takes place as the composite material is moved through this gap. Pressure is applied with the second height limiter, which is optional, and is achieved by ensuring that the gap is smaller than the height of the composite material before it is moved through the gap. This reduces the height of the composite material. The composite material is thus compressed in the vertical direction.

[0029] The first height limitation and / or the second height limitation are designed as an upper barrier, in particular in the form of a lid, the base area of ​​which is in particular greater than or equal to the area of ​​the foam layer.

[0030] The height expansion of the foam layer during partial foaming is limited, in particular, by means of the first height limiter up to the first height. The first height is greater than or equal to the initial height.

[0031] When wetting and impregnating the contact surface of the foam layer with the reaction aid, the contact surface is arranged in particular facing the first height limitation.

[0032] A key finding of the invention is that the foam material is first, in particular at least partially foamed, without any connection or contact with the outer material. Contact and / or connection with the outer material only occurs after the foam material has already been partially foamed and has adhesive properties. In particular, this prevents the outer material from being impregnated by the foam material. This can rule out the possibility of the optical and / or haptic properties of the outer material being negatively affected by the back-foaming. The outer material back-foamed with the foam material has essentially the same optical and / or haptic properties as a composite material produced by flame lamination or adhesive lamination.In particular, unwanted hardening of the outer material as a result of undesired impregnation is avoided.

[0033] It has been found in particular that it is advantageous if the foam material has sufficient strength to be mechanically peeled off as a sheet material. This sufficient strength ensures that the foam material essentially retains its dimensions, in particular the layer thickness of the foam material, during mechanical peeling. This means in particular that the layer thickness of the foam material is not reduced or is only insignificantly reduced during mechanical peeling. In particular, the layer thickness of the foam material after mechanical peeling is at least 90% of the layer thickness of the foam material before peeling, in particular at least 92%, in particular at least 95%, in particular at least 98%, and in particular the layer thickness after peeling is identical to the layer thickness before peeling.

[0034] Furthermore, it is advantageous if the foam material has sufficient adhesive properties to enable bonding to the outer material, in particular by gluing and in particular without additional adhesive material. In particular, the foam material has an adhesion value of at least 6 N / 5 cm after a waiting period of at most 24 hours. In particular, the adhesion value after at most 24 hours is at least 8 N / 5 cm, in particular at least 9 N / 5 cm, and in particular at least 10 N / 5 cm.

[0035] Nevertheless, the connection of the foam layer to the outer material, i.e. the adhesion of the foam layer to the outer material, is sufficiently large and essentially corresponds to the adhesion that can be achieved if the foam layer had been produced with the outer material in a separate joining process, in particular by flame lamination or adhesive lamination.

[0036] Textiles are used in particular as the outer material, in particular textile fabrics, in particular knitted fabrics, woven fabrics, crocheted fabrics and / or scrims made of fiber material. The fibers can be of natural and / or synthetic origin. In particular, the textiles are flame-laminatable or adhesive-laminatable. In particular, the outer material has an adhesion value after lamination of at least 2 N / 5 cm, in particular at least 4 N / 5 cm, in particular at least 6 N / 5 cm, in particular at least 8 N / 5 cm, in particular at least 10 N / 5 cm, in particular at least 15 N / 5 cm and in particular at least 20 N / 5 cm. Flame-laminatable outer materials typically have a temperature resistance of at least 60°C. Such outer materials can be used for the process according to the invention. However, outer materials that have a lower temperature resistance or no temperature resistance are also suitable.

[0037] Films, in particular made of plastic, in particular comprising polyvinyl chloride (PVC), or metal can also be used as the outer material.

[0038] The upper material is typically a composite material made of textile fabric, knit, warp, and / or scrim, coated with a particularly soft PVC and / or polyurethane coating. This type of composite material is referred to as synthetic leather.

[0039] A method according to claim 2 enables a targeted and, in particular, variably definable adjustment of the material properties of the foam material. Depending on the composition of the foam material, a reaction time can be variably determined. The reaction time refers to the wetting and impregnation of the upper contact surface of the foam layer with the reaction aid. During the reaction time, the foam layer is arranged, in particular, at the first height limit. The first height limit serves, in particular, as a lid for the foam layer.

[0040] It is advantageous if the time of contact and / or the pressing duration are determined such that the outer material is placed on the foam layer and bonded to it before the foam layer has completely reacted. The pressing of the outer material is carried out in particular by means of the second height limiter. The pressing duration is reduced compared to the reaction duration and is in particular no more than 2 minutes, in particular no more than 1 minute, in particular no more than 30 seconds.

[0041] A method according to claim 3 prevents undesired adhesion of the foam material to the first height limit. A contact foil, in particular made of plastic material, serves as the contact material. The contact foil is in particular designed as a so-called prepreg foil. A prepreg foil is in particular formed by reinforcing fibers impregnated with a resin, in particular a plastic resin.

[0042] Alternatively, the contact foil can be made of polytetrafluoroethylene (PTFE) foil.

[0043] A method according to claim 4 simplifies the subsequent arrangement and connection of the upper material with the foam layer.

[0044] A method according to claim 5 enables a defined and, in particular, flat-structured production of a composite material consisting of an outer material and a foam material. This ensures the production of particularly thin composite materials. The production of particularly thin composite materials is straightforward.

[0045] A method according to claim 6 ensures sufficient adhesive strength of the composite material. In particular, the adhesive strength of the outer material to the foam layer is at least 6 N / 5 cm, in particular at least 7 N / 5 cm, in particular 8 N / 5 cm, in particular at least 9 N / 5 cm, and in particular at least 10 N / 5 cm.

[0046] In particular, the foam layer is glued to the outer material. A separate adhesive is unnecessary.

[0047] A method according to claim 7 enables a targeted influencing of the foaming and / or bonding of the foam layer to the outer material. In particular, it is possible to set defined temperature profiles that are provided at the first and / or second height limit during the manufacturing process. Such a temperature profile is particularly time-dependent, so that a provided temperature can be set variably during the manufacturing process with a substantially arbitrary temperature profile over time.

[0048] Typically, tempering takes place in a range of at least room temperature and at most 50°C and in particular at most 60°C and over a tempering time of about 3 minutes to at most 12 minutes.

[0049] Depending on the foam material and the outer material used, the tempering parameters, especially duration and temperature, can vary.

[0050] It is advantageous if the provided temperature is distributed evenly across the surface of the foam layer. However, it is also conceivable in principle to provide a temperature profile to heat certain areas more or less, in order to enable a property profile of a composite component produced in this way. The temperature profile enables the production of a composite component with locally varying material properties. The temperature profile can be distributed spatially, in particular across the surface of the foam layer, and / or adjusted to vary along the height direction of the foam layer. However, it is also possible, additionally or alternatively, to design a temperature profile that is variable over time.

[0051] A process according to claim 8 is particularly economical and, in particular, enables the high-throughput production of back-foamed outer material. Such a process is efficient.

[0052] A method according to claim 9 enables uncomplicated provision of the foam material and, in particular, its conveyance. The carrier material used is, in particular, a carrier film, which is designed, in particular, as a so-called prepreg film, particularly analogous to the contact film.

[0053] It is also possible to remove the carrier material from the foam material in a similar way to the contact material, particularly in a downstream process step, and to bond a base material to the foam material, especially if the composite material to be produced has a three-layer design. In the three-layer design, the composite material comprises the outer material, the foam layer, and the base material. The base material can be, for example, circular knit, nonwoven, a knitted fabric, a woven fabric, and / or a film. In particular, the bonding of the foam layer to the outer material and the base material can take place in a single process step.

[0054] A method according to claim 10 ensures continuous conveyance of the foam material along a material conveying direction. In such a method, the respective duration for foaming and / or bonding the foam layer to the outer material can be temporally influenced by means of the conveying speed along the material conveying direction. In particular, it is possible to adjust the conveying speed along the material conveying direction and / or the respective length of the first height limit and the second height limit such that a continuous material flow is enabled while maintaining the required reaction time. Such a method is particularly efficient and very easy to automate. Human interaction is essentially unnecessary.

[0055] A device for backfoaming an outer material essentially has the advantages of the manufacturing method, to which reference is hereby made. The device comprises a base on which the unfoamed foam material can be provided. The device comprises, in particular, a first height limiter. The first height limiter serves, in particular, to limit the vertical expansion of the foam layer during partial or complete foaming up to a first height that is greater than or equal to the initial height. A second height limiter serves to limit the vertical expansion of the foam layer during partial or complete foaming and during bonding of the foam layer to the outer material. It is fundamentally conceivable that one and the same height limiter is used for both process steps, i.e. one after the other in terms of time.However, it has proven advantageous to use separate height stops for the various process steps. It is advantageous if the face material is secured to the second height stop before it is bonded to the foam material. This simplifies the feeding and positioning of the face material to the foam layer.

[0056] A withdrawal element is advantageous, which is arranged, in particular in the material conveying direction, between a foam material feed device, i.e., in particular, the polyurethane foam applicator, and the, in particular, first, height limit and / or the second height limit. The withdrawal element is designed, in particular, as a doctor blade unit. The withdrawal element ensures a predefined height of the foam material, i.e., the starting height. This ensures that the foam material can be fed and connected to the upper material at the, in particular, variably definable, starting height, in particular, the first height limit, and the second height limit. This simplifies limiting the height of the foam material to the first height and / or the second height.

[0057] A device comprising a conveying device that serves to convey, in particular continuously, the foam material, in particular by means of a carrier material, along a material conveying direction, in particular relative to a first height limit and / or relative to the second height limit, enables a continuous manufacturing process. In particular, a conveying device enables a conveying, in particular continuously, of the foam material along a material conveying direction.

[0058] A device comprising a first temperature control unit for controlling the temperature of a first height limit during foaming and / or a second temperature control unit for controlling the temperature of the second height limit during bonding to the outer material ensures targeted adjustment of temperature profiles during production. For this purpose, appropriate temperature control units can be provided, which can be arranged in particular at the height limits and, in particular, integrated therein. The temperature control units can be designed as integrated heaters, for example, as electric heaters and / or as heat exchangers. The temperature control units serve, in particular, to provide heat for the foam reaction and to promote foaming.

[0059] Alternatively, it is possible to design the device without temperature control units and, in particular, to foam the foam material and / or bond it to the outer material at ambient temperature, i.e., without additional heating. The foam material is bonded to the outer material essentially cold. In particular, the maximum temperature of the foam material is 50°C.

[0060] A device having a separating unit for separating the contact material from the foam layer, wherein the separating unit is arranged along the material conveying direction, in particular upstream of the second height limitation, ensures that the foam layer is provided after partial foaming before the foam layer is connected to the outer material.

[0061] A method comprising an upper material feed device for feeding the upper material, wherein the upper material feed device is coupled in particular to the second height limitation, ensures the direct and uncomplicated feeding of the upper material to the second height limitation, in particular for connecting to the foam layer.

[0062] Both the features specified in the patent claims and the features specified in the following embodiments of a device are suitable, either individually or in combination with one another, for further developing the subject matter of the invention. The respective combinations of features do not represent any limitation with regard to further developments of the subject matter of the invention, but are essentially merely exemplary in nature.

[0063] Additional features, advantageous embodiments, and details of the invention will become apparent from the following description of exemplary embodiments with reference to the drawings. They show: Fig. 1 is a schematic representation of a device according to a first embodiment, and Fig. 2 is a schematic representation of a device according to a second embodiment for a continuous implementation of the method.

[0064] One in Fig. 1 The device, designated overall by 1, serves for back-foaming an outer material 2. The device 1 comprises a base 3, which, according to the illustrated embodiment, is designed as a frame-like shape, with a bottom wall and side walls extending vertically upward from the bottom wall. The base area of ​​the base 3 defines the surface area of ​​the foam material. A carrier material 5 in the form of a carrier film is arranged on the base 3 on an upper side facing the foam material 4.

[0065] A first height limiter 6 or a second height limiter 7 can be arranged on an upper side of the mold opposite the base 3. The height limits 6, 7 are designed such that they can be moved relative to the base 3. The height limits 6, 7 are essentially identical. The height limits each have a base area that essentially corresponds to the base area of ​​the base 3. The height limits 6, 7 essentially form a cover for the base 3, wherein the cover can be designed such that it rests on the side walls or can penetrate into the interior of the mold defined by the side walls.

[0066] On an underside facing the base 3, a contact material 8, in particular a contact foil, is attached to the first height limit 6.

[0067] The upper material 2 is attached to the second height limit 7 on the underside facing the base 3.

[0068] The device 1 can have a withdrawal element 9 for defining the initial height h 0 of the foam material 4 prior to foaming. The withdrawal element 9 is arranged so as to be adjustable in the height direction. The initial height h 0 can be variably set by means of the withdrawal element. The withdrawal element 9 is displaceable in particular along a withdrawal direction 10, which is oriented in particular transversely and in particular perpendicularly to the height direction of the foam material 4.

[0069] The foam layer has an upper contact surface 11 facing the respective height limit 6, 7.

[0070] The following is based on Fig. 1 a method for backfoaming the outer material 2 is explained in more detail using the device 1. Unfoamed foam material, i.e. unfoamed polyurethane mass, is applied in a liquid state to the base 3. The initial height h 0 of the foam material 4 is determined by means of the draw-off element 9. During a foaming process, which in particular occurs spontaneously, the foam material 4 expands. In particular, the height of the foam layer expands from the initial height h 0 to a first height h 1 . Further height expansion beyond the first height h 1 is mechanically prevented by the first height limitation 6. The first height limitation 6 represents a mechanical barrier for the foam layer. Water is provided on the contact material 8 as a wetting agent for the foam layer. The wetting with the water promotes and, in particular, specifically influences the further foaming of the foam layer.

[0071] After a defined reaction time, the first height limit 6 is removed and replaced by the second height limit 7. The second height limit 7 is pressed against the upper material 2 at the contact surface 11 arranged in the foam layer.

[0072] By further reacting the foam layer, the outer material 2 is bonded to the foam layer to form a composite material, in particular at the contact surface 11the foam layer 4 is glued. The bonding of the foam layer 4 to the outer material 2 takes place in particular under the application of pressure, i.e. by pressing the second height limitation 7 against the outer material 2. The second height limitation 7 is then removed. The composite material, consisting of the outer material 2 and the foam material 4 connected thereto, can be removed from the base 3. The composite material 2, 4 has a second height h 2 . The foam layer 4 in the composite material has a height that is less than or equal to the first height h 1 that the foam layer 4 has at the first height limitation 6 after the reaction period has ended.

[0073] The device 1 enables a particularly uncomplicated and flexible production of composite components. In particular, the device 1 enables uncomplicated manual operation.

[0074] In the following, with reference to Fig. 2 A second embodiment is described. Structurally identical parts are given the same reference numerals as in the first embodiment, to whose description reference is hereby made. Structurally different but functionally similar parts are given the same reference numerals with an a suffix.

[0075] The essential difference compared to the previous embodiment is that the device 1a enables a continuous manufacturing process.

[0076] For this purpose, the base 3a is equipped with a conveyor device 12, which enables a, in particular continuous, conveyance of the foam material 4 along a material conveying direction 13. According to the illustrated embodiment, the conveyor device is designed as a roller conveyor. Other conveyor devices are also possible. Fig. 2 The material conveying direction 13 is oriented from left to right. The carrier material 5 is arranged on the base 3a.

[0077] The device 1a has a foam material feed device 14, by means of which the, in particular liquid, foam material 4 can be applied to the carrier material 5 on the base 3a. The discharge element 9a is arranged downstream with respect to the material conveying direction 13. In the device 1a, the discharge element 9a is arranged so as to be exclusively vertically displaceable. Relative displacement of the discharge element 9a with respect to the foam material 4 occurs by conveying the foam material 4 along the material conveying direction 13.

[0078] With respect to the material conveying direction 13, the first height limiter 6a is arranged downstream of the discharge element 9a. The first height limiter 6a is arranged statically with respect to the conveying device 12 and is spaced apart from the foam material 4 by a height distance corresponding to the first height h1.

[0079] A contact material feed device 15 is coupled to the first height limiter 6a, which Fig. 2 is shown purely schematically. The contact material feed device 15 serves for the, in particular continuous, feeding of the contact material, in particular in the form of the contact foil 8, at the first height limitation. In particular, the contact material feed device 15 can have a wetting unit 16 which ensures the wetting of the carrier material with the wetting agent, in particular water. In particular, it is conceivable for the contact material 8 to continuously pass through the wetting unit 16 in the contact material feed device 15 and thereby be wetted, in particular automatically, with the wetting agent. Additional effort for wetting the contact material 8 is thereby avoided. In particular, it is conceivable for the contact material 8 to be provided in a circumferential manner via the contact material feed device, i.e. along a closed endless path.For this purpose, the contact material 8 is returned to the contact material feed device 15 downstream of the first height limit 6a.

[0080] According to the illustrated embodiment, the first height limiter 6a has a first temperature control unit 17, by means of which it is possible to apply a specifically adjustable temperature profile to the foam material 4. The first temperature control unit 17 can also be omitted.

[0081] Downstream of the material conveying direction 13, a separating unit 18 is arranged relative to the first height limit 6a. The separating unit 18 simplifies the separation of the contact material 8 from the expanded foam layer 4. This simplifies the return of the contact material 8. In particular, the separating unit 18 ensures that the foam material 4, which is conveyed further along the material conveying direction 13 in the device 1a, contains no residues of the contact material 8. The separating unit 18 ensures reliable separation of the contact material 8 from the foam material 4.

[0082] It was recognized that the contact material 8 is only required in the region of the first height limit 6a. The separation unit 18 can also be omitted. The second height limit 7a is arranged downstream of the first height limit 6a in relation to the material conveying direction 13. The upper material 2 is fed to the second height limit 7a by means of an upper material feed device 19 (not shown in detail). In particular, the upper material 2 is made available by the upper material feed device 19 as endless material, in particular as roll material. This facilitates carrying out the method as a continuous process. The upper material is connected to the contact surface 11 of the foam material 4 in the region of the second height limit 7a. Downstream of the second height limit 7a, the composite material thus produced, which consists of the upper material 2 and the foamed foam material 4 connected thereto, is transported away.The composite material can be delivered to a composite material receiving device not shown in detail, in particular as roll material.

[0083] A second temperature control unit 20 can be arranged at the second height limit 7a and, in particular, integrated into the second height limit 7a. The second temperature control unit 20 can be designed essentially identically to the first temperature control unit 17.

[0084] The following will be based on Fig. 2 A continuous process for backfoaming the outer material 2 is explained in more detail. The liquid foam material is applied to the carrier material 5 by means of the foam material feed device 14. The foam material 4 is continuously conveyed with the carrier material 5 on the base 3a by means of the conveying device 12 along the material conveying direction 13. The starting height h 0 is set in a defined manner by means of the withdrawal element 9a.

[0085] In the area of ​​the first height limit 6a, carrier material 8, which is wetted with a wetting agent, is fed. This ensures that the foam material 4 is wetted with the wetting agent. At the same time, the first height limit 6a ensures a defined height expansion during foaming of the foam material. The height expansion is limited to the first height h 1 . Downstream of the first height limit 6a, the separation unit 18 serves to reliably separate the contact material 8 from the at least partially foamed foam material 4. The separated contact material 8 is returned to the contact material feed device 15.

[0086] The at least partially foamed foam material 4 is fed to the second height limit 7a, where it contacts the outer material 2 at the contact surface 11 and, in particular, is bonded to the outer material 2. In particular, the second height h 2 for the composite material, defined by the second height limit 7a, is set such that the outer material 2 is pressed against the foam material 4 and bonded thereto. In particular, the second height h 2 is smaller than the sum of the material thickness of the outer material 2 and the first height h 1 of the foam material 4 at the first height limit 6a.

[0087] If the composite material is to include a base material in addition to the outer material 2 and the foam material 4, this base material could be bonded to the foam material after the carrier material 5 has been removed from the foam material 4. This allows a three-layer composite material, a so-called trilaminate, to be produced. The base material can be attached to the foam material in a combined process step with the attachment of the outer material 2 to the foam material 4, in an upstream or downstream process step.

[0088] The temperature control units 17, 20 are used for the targeted adjustment of the foaming in the area of ​​the first height limit 6a and / or for connecting to the upper material 2 in the area of ​​the second height limit 7a.

Claims

1. Method for foaming in-situ of a top material comprising the method steps of - providing a reactive foam material (4) in the form of a liquid as foam layer with an initial height (h0), - - at least partially foaming the foam material (4), - limiting a height expansion of the foam layer during partial foaming up to a first height (h1), wherein h1 > h0, - wetting and impregnating an upper contact surface (11) of the foam layer (4) with a reaction aid, - arranging the top material (2) on the contact surface of the foam layer, characterised in that the method further comprises the following method step: - bonding the at least partially foamed foam layer on the contact surface (11) with the top material (2) to form a composite material by means of a second height limit (7; 7a).

2. Method according to claim 1, characterised by a reaction time of at least 2 mins, in particular at least 3 mins, in particular at least 5 mins and in particular no more than 12 mins, wherein the reaction time relates to the wetting and impregnation of the upper contact surface (11) of the foam layer (4) with the reaction aid.

3. Method according to one of the preceding claims, characterised in that a contact material (8), in particular a contact foil, is arranged at a first height limit (6; 6a).

4. Method according to claim 3, characterised by separating the foam layer (4) from the contact material (8), in particular before the top material (2) is arranged on the foam layer.

5. Method according to one of the preceding claims, characterised in that a second height (h2) defined by the second height limit (7; 7a) is between 0.5 mm and 10.0 mm.

6. Method according to one of the preceding claims, characterised in that the foam layer (4) is bonded with the top material (2) by adhesion, in particular adhesion of the impregnated foam layer (4) to the top material (4), wherein in particular a separate adhesive material is dispensable.

7. Method according to one of the preceding claims, characterised by tempering, in particular a first height limit (6; 6a) during foaming and / or the second height limit (7; 7a) during bonding with the top material (2).

8. Method according to one of the preceding claims, characterized in that the method is carried out continuously.

9. Method according to one of the preceding claims, characterised in that the foam material (4) is applied to a support material (5), in particular a support foil.

10. Method according to claim 8 or 9, characterised in that the foam material (4) is moved, in particular by means of the support material (5), continually along a material conveying direction (13), in particular relative to the first height limit (6a) and / or relative to the second height limit (7a).