DE102013021148A1 - Leather exchange material - Google Patents

Abstract

The invention relates to a leather replacement material comprising an outer layer (1) which is external during operation or use, a middle layer (2) connected thereto and a lower layer (3) connected thereto. According to the invention, it is provided that the upper layer (1) is formed from a solidified, crosslinked PU dispersion based on aliphatic polyester and / or polyether, that the middle layer (2) is formed from a knitted fabric or a woven fabric from polyester fibers, that the knitted fabric or Fabric has a basis weight of 190 to 420 g / m2 and a thickness of 0.30 to 0.60 mm, that the lower layer (3) is formed of a foamed plastic, which applied in liquid or pasty form on the middle layer (2) has been that both the upper layer (1) and the lower layer (3) in a thickness (5, 6) of at least 0.050 mm in the middle layer (2) are introduced and inseparably connected to this, and that in the middle layer (2) a layer having a thickness (D) is formed which is free of the plastics used in the upper layer (1) and the lower layer (3).

Description

The invention relates to a leather exchange material according to the preamble of claim 1.

The WO 2012072257 A1 shows a composite material with a Polyurethananschalschaum and a polyurethane dispersion coating on the surface. The composite also contains textile material and a peeling foam. The scarf foam is extremely lightweight, has large, open cells, in which dirt can easily penetrate, and is connected by flame lamination with the textile material. The connection between the peeling foam and the textile material is poor, because during flame lamination the finished foam adheres only by melting on the textile surface. In separation tests it dissolves already at a release force less than 2 N / cm ² from the textile material or is split in itself.

The WO 2011/157279 A1 describes a composite material, which may also be constructed in three layers, in which the back consists either of a polyurethane peel foam, a Polychloroprenschaum or a nonwoven. These prefabricated, solid, additionally applied layers are bonded to the carrier layer either by flame lamination or adhesive bonding. They are mainly used to give the material volume while maintaining low weight. These materials are in solid form and must, as stated, be connected to the carrier. These additionally applied layer or layers are not firmly anchored in the middle layer of the composite material because, as already stated, they are present as finished foams or nonwovens.

The measure of things for interior trim of vehicles and for shoes is genuine leather. It is predominantly used in a thickness between 1.2 and 1.6 mm and usually has a density which is between 0.80 g / cm ³ and 0.90 g / cm ³ . It absorbs moisture and stores it despite its polymer finish. In addition, it is cold- and heat-insulating, has a pleasant feel and a wear-resistant surface and is usually not pitted. The leather has the highest density in its surface (scar layer), the highest strength in its middle layer (leather fiber layer) and on its back a longer fibrous and less dense, loose fiber structure. When processing leather must be often bent. This assumes that it can be sharpened or split from the back, without losing its strength properties. Full-grain leather can be tougher or softer. However, they have an insufficient elongation at break for many applications. This is usually below 100%. Another disadvantage of grain leather is that the adhesion of the polymeric finish is less than 5 N / cm. Often, the flex life, especially at minus temperatures, is not sufficient. Full grain leather is not pressure elastic and does not recover sufficiently after static and / or dynamic stretching. Another advantage of full-grain leather is that it can also be processed unlined for shoes and handbags. This is an important point because leather exchange materials with a fabric or knit backing on their backs are neither sharpening nor splitting. The invention aims at a leather substitute material, which comes in the sum of its properties of a cowhide.

The main object of the present invention is to provide leather exchange materials which are bulky and lightweight, have excellent flex life and in which the different layers consist of different polymers. The constructed in the form of a composite leather exchange material should also be able to absorb and store moisture similar to leather. The leather exchange material should continue to be used for the interior of vehicles and shoe material. It is also part of the object to create leather exchange materials in which the different, different polymers of the top layer and the bottom layer do not interact, and the optical, haptic and physical properties of the top layer, even after a heat storage of 120 ° C over 100 Hours, unaffected. Another object of the invention is to provide a leather-exchange material which has a very thin coating surface and superior abrasion properties in the Martindale ball-plate test DIN EN ISO 17076-2 features. Thin, soft leather and thin, soft leather exchange materials show weaknesses in this test, in which the stressed areas caused by the ball plate protrude from the test area raised. This test destroys thin coatings. In addition, the leather exchange material should work like grain leather, ie it should be sharpening, splitting and buggbar and can be processed without food for shoes and bags. Furthermore, it should behave similar to leather when gluing. The randomly structured surface of the upper layer should have a high resistance to heat and light and remain very well and permanently connected to the carrier layer even under the action of water. Furthermore, the back of the leather exchange material should have an aesthetically pleasing surface which may be smooth or slightly textured.

Flame lamination of PUR peeling foams releases amines, which cause discoloration in light-colored coatings. This should also be avoided.

• – aus einer verfestigten, vernetzten PUR-Dispersion auf aliphatischer Polyester- und/oder Polyätherbasis insbesondere mit amorpher Struktur gebildet ist,
• – dass die Mittelschicht (2)
• – aus einem Gewirke oder ein Gewebe aus Polyesterfasern bzw. -fäden, gegebenenfalls mit einem Anteil von 10 bis 50 Gew.-% an Baumwolle und/oder Zellulosefasern bzw. -fäden gebildet ist,
• – wobei das Gewirke oder Gewebe ein Flächengewicht von 190 bis 420 g/m², vorzugsweise 220 bis 280 g/m², und eine Stärke von 0,30 bis 1,0 mm (gemäß DIN EN ISO 2589 ), vorzugsweise von 0,30 bis 0,60 mm, insbesondere von 0,30 bis 0,50 mm, besitzt, und gegebenenfalls das Gewebe eine Bruchdehnung in beiden Richtungen zwischen 25 und 90% (gemäß DIN EN ISO 3376 ), vorzugsweise zwischen 35 und 70%, und das Gewirke in beiden Richtungen eine Bruchdehnung zwischen 75 und 450% aufweist, und
• – dass die Unterschicht (3)
• – aus einem geschäumten Kunststoff gebildet ist, der in flüssiger oder pastöser Form auf die Mittelschicht (2) appliziert wurde oder
• – aus einer Kunststoffdispersion, insbesondere einer verfestigten amorphen, vernetzten, aliphatischen oder aromatischen PUR-Dispersion, gebildet ist, die mit der Mittelschicht (2) verbunden und auf ihrer der Mittelschicht (2) abgewandten Seite mit einer Außenschicht (12) verbunden ist bzw. eine Außenschicht (12) umfasst.

According to the invention the above objects are achieved in a leather exchange material according to the invention with the features cited in the characterizing part of claim 1. According to the invention, it is provided that the upper layer ( 1 )

• Is formed from a solidified, crosslinked PU dispersion based on aliphatic polyester and / or polyether, in particular having an amorphous structure,
• - that the middle class ( 2 )
• Is formed from a knitted fabric or a woven fabric of polyester fibers or filaments, optionally with a proportion of 10 to 50% by weight of cotton and / or cellulose fibers or filaments,
• - wherein the knitted or woven fabric has a basis weight of 190 to 420 g / m ² , preferably 220 to 280 g / m ² , and a thickness of 0.30 to 1.0 mm (according to DIN EN ISO 2589 ), preferably from 0.30 to 0.60 mm, in particular from 0.30 to 0.50 mm, and optionally the fabric has an elongation at break in both directions between 25 and 90% (according to US Pat DIN EN ISO 3376 ), preferably between 35 and 70%, and the knit has an elongation at break between 75 and 450% in both directions, and
• - that the lower class ( 3 )
• - is formed from a foamed plastic which is in liquid or pasty form on the middle layer ( 2 ) was applied or
• Is formed from a plastic dispersion, in particular a solidified amorphous, crosslinked, aliphatic or aromatic PU dispersion, which is in contact with the middle layer ( 2 ) and on its middle class ( 2 ) facing away with an outer layer ( 12 ) is connected or an outer layer ( 12 ).

Since the leather exchange material according to the invention is compared with grain leather, especially with regard to its processability, the tests were carried out according to standard leather tests.

It has been found that the leather exchange materials according to the invention have extremely good and durable tensile and compressive elastic properties, that the layers used or bonded together adhere to one another almost inseparably and show high resistance to heat and light. Furthermore, the leather exchange material can absorb and release water through any capillaries and / or microperforations provided. Furthermore, the leather exchange material is bulky and lightweight. If the topsheet and the backsheet are not in contact with each other, any existing softeners or chemical substances that are to be confined to the backsheet can not migrate to the topsheet.

High strength results when both the topsheet and the backsheet are at least 0.050 mm thick in the middle layer and inseparably bonded to it.

It is advantageous if in the middle layer, a layer is formed with a thickness which is free of the plastics used in the upper layer and the lower layer, and their strength at a pressure load of the leather exchange material of up to 2 kg / cm ² direct contact prevented from upper layer and lower layer and ensures a distance between the upper layer and the lower layer of at least 0.15 mm.

When the middle layer is substantially midway between the topsheet and the backsheet or outer layer and has a polymer-free zone at its center, the finished leather-exchange material remains particularly soft and has low flexural rigidity and high tear and puncture resistance.

High strength values result when the solidified PUR dispersion used for the upper layer and penetrating into the middle layer and the solidified PU dispersion used for the lower layer and penetrating into the middle layer meet in the middle region of the middle layer. It is expedient if the solidified PU dispersion of the upper layer and the lower layer have the same or a very similar structure and / or have the same or a very similar Shore A hardness.

The leather exchange material of the present invention is excellent in the Martindale ball-plate test despite its thin surface coating. As a result of the construction according to the invention and the compressive elasticity of the material according to the invention, the balls of the ball plate press into the rear foam or the lower layer and the outer layer and into the middle layer, so that the test surface remains substantially smooth or planar.

Similar to leather, the material can be sharpened, split and rolled over because the wearer with the thin upper layer is not weakened or hardly weakened. With the intended thickness and the weight of the middle layer, their meshes can be so close together that there are no voids of more than 0.25 mm between the fibers or yarns of the middle layer, so that even under pressure and the stress in practice the polymers the upper and lower classes do not come into contact with each other. This is especially important if the backsheet is made of polymers (such as PVC) containing plasticizers.

To a particularly durable and hard-wearing upper layer of the leather exchange material according to the invention contributes, if it is provided that the upper layer has a thickness of 0.10 to 0.22 mm, preferably from 0.12 to 0.15 mm, and / or a Shore A. Hardness of 22 to 88, preferably from 45 to 65, and / or has a homogeneous structure and / or has a density of 0.95 to 1.15 g / cm ³ . If the upper layer is multi-layered, its inner layer, which is in the middle layer 2 partially penetrated, have a Shore A hardness of less than 22 Shore A, preferably between 2 and 15 Shore A.

When a polymer-free layer is formed in the middle layer, contact between the top layer and the backsheet is avoided, in particular, when the knitted or woven fabric is pressure-elastic and the middle layer elastically returns to its original position up to a load of 1.0 kg / cm ² .

A well-flexible and highly durable leather exchange material results when the backsheet is made of a foamed, solidified plastic dispersion, e.g. As an aromatic and / or aliphatic polyurethane dispersion, optionally with a maximum of 30 wt .-%, polyacrylates.

In an alternative embodiment it can be provided that a nonwoven fabric made of synthetic fibers is attached as the outer layer to the lower layer formed by a solidified PU dispersion. This fleece contributes, above all, to the tensile and compressive elasticity and strength of the leather exchange material, without impairing its bendability.

In order to ensure the tensile and compressive elasticity of the leather exchange material and a low weight, it can be provided that the lower layer has a density of 0.30 to 0.85 g / cm ³ and / or under a load of 1 kg / cm ² μm at least 25% is reversibly compressible and / or has a thickness of 0.15 mm to 0.60 mm, preferably from 0.20 mm to 0.40 mm.

The durability of the leather exchange material is enhanced when the backsheet is formed from a plastic dispersion baffle having open cells or formed from a PVC plastisol containing propellants and having heat-sealed cells by solidification, or formed from a plastic dispersion. contains the hollow plastic microspheres that form closed cells.

In order to be able to realize a variety of applications, in particular in the motor vehicle industry, provision may be made for flameretardant additives to be contained in the middle layer and / or in the underlayer and / or in the bonded outer layer of a PUR foam film or nonwoven.

The moisture resistance and color fastness of the leather exchange material can be influenced or optimized if in the top layer and / or in the underlayer additives, preferably silicone emulsions and / or dispersions and / or pigments in a total amount of up to 25 wt .-% , preferably up to 21 wt .-%, based on the total weight of the dispersion are included.

An extremely high tear propagation and Stichausreißfestigkeit, which is far above the strengths of the same leather, results when the middle class 2 near, inner layer of the upper layer has a Shore A hardness of less than 22 Shore A, preferably between 2 and 15 Shore A, and is connected to the middle layer or introduced into this.

Moisture transport is made possible if it is provided that pores and / or capillaries are formed in the upper layer and / or if perforations, in particular microperforations, are formed in the lower layer which continue into the upper layer or run through it.

For the intended purposes it is advantageous for the leather exchange material according to the invention if the leather exchange material has a thickness of 1.00 to 1.80 mm, preferably 1.20 to 1.50 mm, and / or a basis weight of less than 800 g / m ² , preferably less than 700 g / m ² .

In order to improve the possible applications, it may be provided that the lower layer contains pigment and / or one or more layers and / or carries on its surface facing away from the upper layer as the outer layer a final coat of polyacrylate or polyurethane in a thickness of less than 0.01 mm , This is particularly advantageous if the lower layer consists of a soft PVC foam.

A contact of the upper layer and the lower layer is particularly well avoided if the meshes in the middle layer are close together and the voids between the fibers or threads have dimensions smaller than 0.30 mm, in particular 0.25 mm.

In terms of strength, it has proved to be advantageous if hollow microspheres are present in the underlayer in an amount of 6 to 12% by weight, based on the weight of the polymer dispersion.

It is advantageous for use if the surface of the top layer has the structure of embossed nubuck leather with scarcaps and scarabs formed on a negative template and / or if the surface of the top layer has regions with a different surface structure. It is possible with the successful leather exchange material to form the surface in the course of manufacture accordingly. Furthermore, it is possible shape blanks, z. As shoe parts to form with different surface structures on the same part. A zone or an area may, for. B. have a very matte nubuck surface and another zone a glossy paint surface or a logo. The different structures are formed in silicone rubber molds by lasers, ie the die is negatively lasered and the surface is molded. Such matrices for the production of differently textured surfaces on leather are in the US Pat. No. 6,177,198 B1 described.

• – eine Shore A Härte von 6–14, vorzugsweise von 8 bis 12, besitzt und/oder
• – eine Dichte von 0,15 bis 0,32 g/cm³, vorzugsweise von 0,18 bis 0,22 g/cm³, besitzt und/oder
• – die PUR-Schaumfolie aus einem, vorzugsweise aromatischen, Polyäther- oder Polyester-Polyurethan gebildet ist und/oder
• – die verfestigte PUR-Dispersion der Unterschicht zumindest 0,30 mm in die offenzellige PUR-Schaumfolie eingedrungen ist. Die einzelnen Parameter tragen jeder für sich zur Verbesserung der Eigenschaften des Lederaustauschmaterials bei und ergeben in Kombination unerwartete Verbesserungen des Gewichtes, der Festigkeiten und der Biegeeigenschaften. Diese Rückseite fühlt sich gut an, sieht gut aus, nimmt Feuchtigkeit auf und erhöht den Tragekomfort bei Schuhen und den Sitzkomfort bei automobilen Innenausstattungen.

A further advantageous alternative embodiment provides that a PUR film having a thickness of 0.60 to 1.20 mm, preferably 0.80 to 1.0 mm, is bonded to the PUR dispersion as the outer layer. In particular, the tensile and compressive elasticity, the bending behavior and the elongation at break are positively influenced. Appropriately, it is provided that the PUR film has an open-cell and fine-cell foam structure and / or

• - Has a Shore A hardness of 6-14, preferably from 8 to 12, and / or
• - Has a density of 0.15 to 0.32 g / cm ³ , preferably from 0.18 to 0.22 g / cm ³ , and / or
• - The polyurethane foam sheet is formed from a, preferably aromatic, polyether or polyester polyurethane and / or
• - The solidified PU dispersion of the lower layer at least 0.30 mm has penetrated into the open-cell PUR foam sheet. The individual parameters each individually contribute to the improvement of the properties of the leather exchange material and, when combined, provide unexpected improvements in weight, strength and flexural properties. This back feels good, looks great, absorbs moisture and increases the comfort of wearing shoes and the comfort of sitting in automotive interiors.

Low-stretch polyester fabrics also include a polyester fabric into which polyester fibers have been introduced (eg by needling). The polyester fabric with the introduced polyester fibers, which protrude fleece-like on both sides, has a basis weight between 200 and 300 g / m ² and a thickness between 0.5 and 0.8 mm.

In practice, it is advantageous if the leather exchange material has a Shore A hardness of from 25 to 65, preferably from 20 to 50.

The examination of the Shore A hardness of the leather exchange material according to the invention or individual layers thereof is always such that the leather exchange material or the individual worked out from the leather exchange material individual layers to be tested are superimposed until the required for the Shore A hardness test thickness of the test piece of mm is created. This specimen formed of a number of superimposed layers is then subjected to the Shore A hardness measurement. This is true not only for the finished leather exchange material, but also for the middle layer 2 and the lower class 3 , From the solidified, crosslinked dispersion formulation of the layer 1' a test specimen with a dimension of 6 mm is prepared which has a Shore A hardness of 35 to 88 Shore A, preferably between 45 and 60 Shore A. For the shift 1'' Also, a test specimen is prepared from the solidified, crosslinked dispersion formulation having a Shore A hardness of less than 22 Shore A, preferably between 2 and 15 Shore A. The determined value is reduced after 15 seconds by about 10%, which is due to a cold flow.

The stated thicknesses of the materials or layers, in particular of the PUR foam film or layers, and the thickness of the nonwoven fabric and the knitted fabric and fabric are according to DIN EN ISO 2589 measured.

High-grade properties of the leather exchange material according to the invention also result when the textile layer bonded to the consolidated PUR dispersion of the lower layer is a textile material, preferably a nonwoven fabric or a nonwoven fabric made of synthetic fibers, having a thickness of between 0.6 and 1.2 mm having. In this alternative embodiment it can be provided that the nonwoven fabric is a needle-punched nonwoven or a nonwoven consolidated by sewing or embossing and / or solidified by heat treatment and shrinkage of the fibers and / or that the nonwoven fabric has a basis weight of between 80 and 200 g / m ² has. Preferably, the fleece of the outer layer consists exclusively of polyester fibers and may optionally be additionally consolidated by sewing with two threads or with a thread, as a so-called loop composite. If the polyester nonwoven contains fibers between 5 and 25% by weight, which become plastic at a temperature above 100 ° C., the fibers can be additionally joined. These preferably mentioned nonwovens contribute to increasing the breaking load, which means that the final strength is also achieved with a woven or knitted fabric that is only 190 g / m ² or is easier. This makes the middle class 2 and the tethered outer layer 12 predominantly made of polyester fibers, recycling or disposal is easily possible and it does not interact even if the extremely soft inner layer of the upper layer in the form of a cold flow deep into the middle layer 2 or even entirely into the middle class 2 has penetrated. This structure is similar to a natural grain leather, which is a quasi sandwich construction, but in which the leather layer and meat side layer have different structures, but chemically have the same structure, as in the above-mentioned preferred embodiment.

For the strength and flexibility, it is advantageous if the consolidated PUR dispersion of the lower layer has a Shore A hardness of 8 to 22 Shore A, preferably from 6 to 15 Shore A.

The outer layer worn by the lower layer can also assume the function of a lining in the case of shoes and bags, especially if the outer layer is a PUR foam film. It can be provided to apply a pigment or dyes containing polyurethane or polyacrylate dispersion on the back of the outer layer or PUR foam sheet so that it penetrates at least 0.2 mm into the open cells and this area dyes and the photosensitivity of the aromatic polyurethane foam sheet eliminated.

For strength and flexibility, it is expedient for a sub-layer impact foam penetrated into the middle layer to have the structure of a non-foamed solidified plastic dispersion in the penetration areas and / or the amorphous, preferably polyether-based solidified PU dispersion of the sub-layer to have a basis weight of 30 to 90 g / m ² has.

According to the invention, there is the advantage that the elongation at break of the middle layer does not change due to the upper layer and lower layer. The top layer alone has an elongation at break of at least 350%. The underlayer, depending on the structure, has an elongation at break between 60 and 400%.

Particularly advantageously, the leather exchange material according to the invention is suitable for the interior decoration or lining of the interior walls of vehicles, for shoes, for bags or for handbags as well as for sheet or plate goods and custom blanks for shoes, bags and car interior trim.

In the drawing is shown schematically in 1 a section through an inventive leather exchange material in unloaded and in 2 shown in loaded condition.

3 shows a section through an alternative embodiment with a PUR film as the outer layer.

4 shows an embodiment with a middle layer, which is formed with a fabric and a non-woven.

The leather exchange material according to the invention comprises a layer structure with a top layer 1 , a middle class 2 and an underclass 3 , which are each connected to each other. The upper class 1 may be single or multi-layered, advantageously from mutually identical layers 1' . 1'' be constructed of identical or similar material. In the upper class 1 or wear layer can capillaries or pores 4 be formed, in particular in the production of the upper class 1 were trained on a mold.

The upper class 1 consists predominantly of a solidified and crosslinked polyurethane dispersion based on aliphatic polyester and / or polyether and has an amorphous structure. The upper class 1 has a thickness between 0.10 and 0.22 mm, preferably between 0.12 and 0.15 mm. It can be prepared in a known manner on a negatively structured silicone rubber backing or on a negatively structured, so-called release paper. It has a hardness of 22 to 88 Shore A, preferably from 45 to 65 Shore A.

The upper class 1 can known additives such. As silicone emulsions to handle improvement and pigments. Depending on any pigments and additives used, the upper layer has 1 a density of 0.95 to 1.15 g / cm ³ . It can consist of several, but at least two layers. The individual layers are joined in the course of their production while they still contain water and are not cross-linked. Thereby they connect to an inseparable layer. Any existing pores and capillaries are in the upper layer 1 ,

According to the following properties are substantially improved. Stichausreißfestigkeit, tear propagation resistance, restoring force, compressive elasticity, but especially the flex life at normal and minus temperatures when the upper class 1 from two layers 1' . 1'' exists, wherein the inner connection layer, so the layer into the middle layer 2 penetrates extremely soft and in uncrosslinked state, but after evaporation of water, has excellent contact adhesive properties. By this is meant that two layers, made of the polyurethane dispersion, put together under a pressure of 100 g / cm ² no longer destructive can be separated. After crosslinking, the solidified dispersion has a Shore A hardness between 2 and 15 Shore A. An 80% aqueous polyisocyanate crosslinker is used at between 4 and 10%. After 15 seconds, the displayed Shore A hardness is reduced by more than 10%, which is due to a so-called cold flow. This solidified dispersion has an amorphous structure and preferably consists of a polyether polyurethane. The puncture and tear propagation resistance is improved by softness and the cold flow, because the threads and yarns of the layer 2 can move elastically at the crossing points. This is true even if this dispersion is deep in the middle layer 2 penetrated so deep that they contact with the solidified, chemically same or similar dispersion, with which the lower layer 3 with the middle class 2 connected has.

The carrier or middle layer 2 exists at the in 1 and 2 illustrated embodiment of a knitted fabric or fabric of polyester fibers, preferably from a knitted fabric or fabric, which consists of mixed fibers, such as. As polyester-cotton fibers or polyester-cellulose fibers. The carrier layer has a basis weight of 190 to 420 g / m ² , preferably from 220 to 280 g / m ² , and a thickness of 0.30 to 0.60 mm, preferably from 0.40 to 0.50 mm. In a preferred embodiment, the middle layer contains 2 between 10 and 50% cotton and / or cellulose fibers. The middle class 2 has small meshes, smaller than 0.30 mm, especially smaller than 0.25 mm.

The foamed lower layer 3 consists of a solidified plastic dispersion and has a thickness of 0.15 mm to 0.60 mm, preferably from 0.20 mm to 0.40 mm. It has an open-celled foam structure, as it arises when smearing or stirring air into a dispersion. It is inseparable from the middle class 2 connected, because they as a so-called Schlagschaum in their liquid phase with the middle layer 2 was brought together and at least 0.05 mm has penetrated into this and has also anchored there mechanically.

The lower class 3 is tensile and compressive elastic deformable such that it is reversibly compressible at a load of 1 kg / cm ² at least 25%.

As the light fastness of the lower layer 3 is not important, come here, in contrast to the upper class 1 , inexpensive polymers are used. It is important that the polymers are foamable either by stirring in air, which is possible with most polymer dispersions with the concomitant use of emulsifiers or the use of a blowing agent which allows foaming. Above all, dispersions with a solids content of more than 40% are well suited for this purpose. There are uniform dispersions such as aromatic polyurethane dispersions, polyacrylate or mixtures of these two in question. Preferably, dispersions with elastomeric properties in the solidified state in question, which are reversibly deformable. Such open-cell, solidified dispersions, so-called impact foams, have a typical Schlagschaumstruktur and take on similar to leather water, which is advantageous for the carrying or seating comfort. In the resting phase, the moisture is released faster than leather. The one for the lower class 3 used dispersions are solidified, elastic and usually form open-celled foams.

For certain applications, it is important that the different polymers that make up the upper layer 1 is formed, and those polymers that make up the lower layer 3 is formed, do not get in contact with each other to avoid interactions. This, though both layers 1 . 3 each in a thickness of at least 0.05 mm in the carrier layer 2 have penetrated. According to the invention between the in the carrier layer 2 penetrated polymer of the upper layer 1 and in the carrier layer 2 penetrated polymer of the lower layer 3 maintain a distance of at least 0.015 mm even under pressure of 2 kg / cm ² . This ensures that even under the harshest conditions, the two layers 1 . 3 do not touch. 2 shows a loaded with pressure P leather exchange material, wherein the thickness of the unloaded middle layer 2 is reduced to a thickness D '. In such a leather exchange material thus no plasticizer in the upper layer 1 migrate; the polymer-free region of the middle layer 2 serves as a barrier to plasticizers.

According to the invention, the lower layer 3 also made of a soft PVC foam or a soft PVC. Also in this case the liquid plastisol becomes the lower layer 3 with the middle class 2 inseparably brought together and penetrates in one strength 6 ( 1 ) of at least 0.05 mm in this one.

A PVC-containing foam of the underlayer 3 is predominantly closed-celled and shows a thin skin on its outer or back. It is used in products in which a water absorption is undesirable, such. B. in boat building or motorcycle seats. The lower class 3 is in liquid or pasty form on web goods of the textile material of the middle class 2 applied so that they are at least 0.05 mm into the middle layer 2 penetrates. The Application takes place by means of a doctor blade or roller application, directly or indirectly on the carrier or the middle layer 2 ,

The liquid whipped foam of the lower layer 3 is solidified by dehydration by heat between +80 and + 180 ° C. When using a plastisol containing a propellant, the lower layer becomes 3 thereby solidified with simultaneous foaming of the plastisol. In this consolidation of the lower class 3 A thin skin forms on the foam in the desired manner, which, in contrast to a peeling foam, prevents the penetration of dirt.

The prepared material, consisting of the middle layer 2 and the lower class 3 , can then for the production of the leather exchange material both in the form of sheet goods as well as a formatting cut in a known manner in the reversal process with the top layer 1 provided or on the upper class 1 At the same time, the surface structure is also designed with a silicone matrix or a release paper.

For special applications, but especially for the application or application of the applied on a die dispersion of the upper layer 1 at the middle class 2 , the underclass can 3 Microperforations contain, through which the water of the upper class 1 can evaporate forming dispersion. According to the invention, for special applications, the leather exchange material can also be provided with microperforations, in particular through the cross section or its entire thickness.

By combining high quality polymers in the upper class 1 and inexpensive polymers in the foamed lower layer 3 the task is not only achieved, but even surpassed. For example, after DIN EN ISO 11644 a liability between the upper class 1 and the middle class 2 of more than 10 N / cm ² , preferably more than 20 N / cm ² . For samples of known layer materials, in which the lower layer 3 in the middle, and the middle class 2 as lower area or as lower layer 3 is arranged, the adhesion values are up to 40% lower, because the foam splits.

The abrasion properties are extremely high. Thus, in the leather exchange material produced according to the invention in the Taber test, carried out in accordance with DIN 53109 with a friction wheel of grain size H18, after 2000 tours no damage, while test specimens known layer materials in which a foam middle layer was used, already after 1000 tours had damage.

Regardless of the strength, the foamed backside of the leather exchange material, formed from a whipped foam or micro-perforated PVC foam, has a water vapor permeability DIN EN ISO 20344 of at least 2.4 mg / cm ² · h.

The middle class 2 and the lower class 3 and the on layer 3 tethered outer layer 12 may contain flame retardant additives.

With the leather exchange material according to the invention all tasks can be optimally fulfilled, because the middle layer 2 is about in the middle of the leather exchange material and the volume bringing, soft, pressure-elastic layer is located on the back, and because the middle layer 2 in their midst one of the plastics of the upper class 1 and the lower class 3 may have free zone.

The leather exchange material according to the invention has a weight of less than 700 g / m ² at a thickness of 1.4 mm and is therefore more than 30% lighter than a grain leather of the same thickness. Due to its properties, it is ideal for seat covers of vehicles, aircraft and ships. The surface of the upper class 1 can have a nubuck-like structure, which, in contrast to real nubuck leather, is very light-fast, dirt-repellent and resistant to abrasion and scratching and fully meets the requirements of the automotive industry.

The pores or cells in the lower layer 3 are according to the invention a maximum of 0.04 mm in size. In contrast, the pores of a peelable foam used in the prior art are 4 to 8 times larger.

The upper class 1 may also have fine capillaries which are microperforated or, when forming the topsheet 1 , Evolved by evaporation of water from the polyurethane dispersion.

The foamed lower layer 3 may also have, if it is formed from a polymer dispersion, a predominantly closed-cell structure, namely, when in the liquid dispersion microballoons having a diameter of 20 to 60 microns in an amount between 6 and 12 wt .-% based on the polymer dispersion introduced are, whose shell is made of thermoplastic material. In this case, both open and closed cells are formed. The specified parameters remain for the lower layer 3 unchanged.

The lower class 3 may contain pigments, may be single-layered or multi-layered and on theirs the upper class 1 surface facing a final coat of polyacrylate or polyurethane in a thickness of less than 0.01 mm, especially if the lower layer 3 formed with a foamed PVC material. The final coat prevents plasticizer migration through contact with other materials and positively influences the feel.

The invention is explained in more detail below on the basis of examples:
Example 1: A mixed fiber knitted fabric of 70% polyester and 30% cotton fibers and having a basis weight of 370 g / m ² and a thickness of 0.5 mm is used as a middle layer 2 used and with a the lower layer 3 coating foam. The whipped foam consists of 60% of a 40% aromatic polyether dispersion and 40% of a 50% polyacrylate dispersion. 5% by weight of aqueous isocyanate crosslinker and 2% by weight of a foam aid as emulsifier were added to the dispersion mixture. The mixture had a density of 1.05 g / cm ³ . By stirring in air to a density of 0.65 g / cm ³ , the mass was foamed, and applied by means of a doctor blade in a thickness of 0.45 mm on a release paper. On the wet dispersion became the middle layer 2 or the carrier and the lower layer 3 put it on and slightly pressed with a roller until the foam dispersion has penetrated 0.015 mm into the carrier. After drying for 4 min at + 90 ° C, the middle layer became 2 with the lower class 3 separated from the releasepaper. The lower class 3 has a fine-pored, open-celled structure and a density of about 0.45 g / cm ³ .

The topsheet formed from an aliphatic polyester polyurethane having a 48% solids amorphous structure 1 consists of two layers 1' . 1'' , wherein the outer, upper layer 1' the upper class 1 applied to a structured release paper or textured silicone rubber matrix and heat-set by dehydration. This upper class 1 consisting of layer 1' and 1'' has a Shore A hardness, measured from the top, between 35 and 52 Shore A. The Shore A hardness was determined after crosslinking. After that, on this layer 1' an also consisting of an aliphatic, amorphous polyester dispersion layer 1'' applied, this layer has after curing a Shore A hardness of 6 to 15 Shore A. On the still moist layer 1'' The middle layer is placed and lightly pressed by a roller. This layer construction alone leads to a Shore A hardness between 55 and 88 Shore A.

Alternatively, as an upper, outer layer 1' in thinner (less than 0.09 mm, preferably less than 0.04 mm) thickness, a polyurethane dispersion can be applied to the matrix. This layer 1' is pre-dried so that it contains more than 5% water. The chemically same but physically softer dispersion formulation becomes a layer 1'' , also in thin thickness on the middle layer 2 with an amount between 30 and 90 g / m ² , preferably between 40 and 60 g / m ² , applied so that they are about 0.05 mm into the carrier or the middle layer 2 penetrates. After that, the middle class becomes 2 with the at least 20 wt .-% water-containing polyurethane dispersion on the preconsolidated layer 1' applied and pressed with a pressure of less than 0.4 kg / cm ² either with a roller or plate press. Thereafter, the material is subjected to a heat treatment between 70 and 120 ° C. The moisture initially migrates to the middle layer 2 and then through the open pores or capillaries of the lower layer 3 escape. This application of the upper class 1 applies to all examples.

The thickness of the resulting topsheet is 0.15 mm with a Shore A hardness of 58 and a density of 1.05 g / cm ³ .

Example 2: On a release paper, a propellant-containing PVC plastisol in a thickness of 0.2 mm was applied by means of a doctor blade. On that the underclass 3 plastisol forming was the same the middle layer 2 forming carrier as laid out in Example 1 and slightly pressed by a roller, so that the plastisol penetrated about 0.05 mm into the knitted fabric. At a temperature of + 182 ° C and a time of 4.5 min, the PVC plastisol was foamed and solidified by gelling to a thickness of 0.4 mm and a density of about 0.6 g / cm ³ . After cooling, it was separated from the release paper.

Example 3: A mixture consisting of 75 parts by weight of a 50% polyurethane dispersion and 25 parts by weight of a 50% polyacrylate dispersion has a density of about 1 g / cm ³ . There were so many hollow microspheres mixed with a diameter between 20 and 60 microns until one liter of liquid weighs 850 g. The shell of the hollow microspheres consists of a thermoplastic plastic, preferably polyvinylidene chloride. This approach for the lower class 3 is applied with an opposing roller, squeegee or by spraying on the middle layer 2 applied, so that this lower layer pulls about 0.06 mm in this. Subsequently, the middle class 2 dried with the wet coating in a tunnel at an inlet temperature of 100 degrees Celsius and an outlet temperature of about 145 degrees Celsius. In the process, the dispersion crosslinks and more than 95% of closed cells are formed. According to the invention, it is also possible in this approach for the lower layer 3 stir in any amount of air and thus a whipped foam to create. In this case arise in the lower class 3 closed and open cells.

In the education of the lower class 3 with an outer layer 12 in the form of a PUR film can be proceeded according to Example 4.

Example 4: As outer layer 12 a PUR foam sheet is provided with a thickness of 1 mm and a density of 0.2 g / cm ³ , which has predominantly fine open cells. It consists of Polyetherpolyurethan and has a Shore A hardness of about 10 Shore A. This foam sheet was produced by the compression and compression under temperature and pressure of a correspondingly thicker Schälschaumfolie. This film is relatively smooth and fine-pored on both sides, it works well and can serve as food. A dispersion mixture consisting of 75 parts of an alipatic aromatic polyether dispersion and 25 parts of a polyacrylate dispersion is applied to this foam film in an amount of 75 g / m ² in such a way that about 30 g into the open cells of the foam sheet and about 45 g in the middle layer carrier 2 penetration. After a drying time of about 4 min. At 100 ° C, the water is evaporated. This underclass 3 between the middle class 2 and the outer layer 12 that is virtually absent because they are in the two layers 2 . 12 penetrated, leads to a hardness of 10 to 17 Shore A.

In a further preferred embodiment, it can be provided that in the case of a comparable production method, instead of the PUR foam film, the solidified PUR dispersion of the lower layer 3 a textile material, preferably a nonwoven fabric or a nonwoven fabric of synthetic fibers, as an outer layer 12 is connected, which has a thickness between 0.6 to 1.2 mm. This nonwoven can be a needle-punched nonwoven or a water-jet-bonded or heat-shrink-bonded nonwoven thermoformed by stitching or embossing and have a basis weight of between 80 and 200 g / m ² . This back has the advantage that it is very light, very soft and pressure-equalizing and at the same time serves as lining material. In addition, it contributes to increasing the breaking load.

For the construction of the leather exchange material according to the invention, it is advantageous if the solidified PU dispersion of the lower layer 3 It has a Shore A hardness of 2 to 15 and has a slight cold flow, as it has the mid-layer elongation at break 2 preserved.

The surface of the leather exchange material may have geometric shapes or protrusions and depressions. The elevations forming surfaces of the matrix may be light or finely ground, such that these sanding marks on the material, for. B. at 100-fold magnification, are visible. This considerably improves the feel and appearance. The leather exchange material according to the invention may have a surface which has differently structured regions. This means that the leather exchange materials have an appearance as if they were made with materials of different surface structure and / or different gloss level, for example by sewing. Seams formed in this manner look very similar to properly executed seams. The desired surface structures can be lasered into the silicone rubber matrices used for the production of the format sections, or the desired structures are lasered into a plastic film or plastic plate and shaped with silicone rubber.

The advantage of the tensile and compressive elastic layers, ie the middle layer 2 and the lower class 3 and the outer layer 12 , achieves the design of structures on the surface of the upper class 1 which structures optimally reproduce all elevations and depressions as well as seams, as they are predefined in the matrix. In particular, this is advantageous for the formation of surfaces with the appearance of embossed nubuck leather. It is advantageous in this case that the seam crests and Nahttäler have the same fine structure and the same gloss.

In conventional leather and artificial leather, the nubuck surface is created by grinding. During grinding, however, only the scar bodies can be ground. If you want to grind into the valleys, you lose the knolls. If, after full-surface grinding, heat and pressure are usually applied, the surface in the grapevines is more compacted, thus losing the nubuck effect in the valleys. The more pronounced the effect is, ie the higher the crests and the deeper the valleys are, the worse the result becomes when imprinting. This is especially true for genuine nubuck leather. In particular, however, this applies to nubuck effects, which are formed by grinding fine-pored foams. Due to the grinding, especially in ground, thermoplastic foams, the valleys are shiny. If the ground foam is an elastomer, it can not be permanently embossed. In contrast, according to the invention, the nubuck effect or the structure is already present in the negative in the silicone rubber matrix by molding or by laser. The pressure-elastic layers 2 respectively. 3 even allow structures with grapevines with a depth of up to 0.2 mm. Thus, the Narbtäler and Narbkuppen have the same nubuck structure and the same dullness or the same degree of gloss.

4 shows an embodiment of the invention, in which the fabric of the middle layer 2 is formed such that the middle layer 2 from a polyester fabric is formed, which with a polyester fleece 14 mechanically connected. It is envisaged that the fibers 13 of the central in the fabric embedded polyester fleece 14 protrude on both sides of the polyester fabric, and that the solidified polyurethane dispersions of the upper layer 1 and the lower class 3 up to the polyester fabric in the layer 2 penetrated and the polyester fabric is connected on both sides with the solid polyurethane dispersions and the fibers 13 of the polyester fleece 14 to the upper class 1 and in the lower class 3 protrude. This leather exchange material has a high tensile strength, a low elongation and does not deform in practice.

According to the invention it is thus possible, with otherwise constant parameters as the middle layer 2 to use a woven or knitted fabric, optionally with a fleece insert.

In general, it is possible to contact the lower class 3 connected outer layer 12 as PUR foam film or fleece to design.

Not shown in 3 is the possibility that on the back of the outer layer formed by a PUR foam sheet 12 , preferably nonwoven, an additional layer of a solidified polyurethane and / or polyacrylate dispersion is applied, which is at least 0.30 mm in the open cells of the outer layer 12 has penetrated and optionally contains colored pigments.

The leather exchange material according to the invention can absorb water from its rear side, through the outer layer 12 or the lower layer 3 and through the middle class 2 to the upper class 1 can be derived.

The flex life of the leather exchange material according to the invention DIN EN ISO 5402 (Bally Flexometer) is with 200,000 flexes at normal temperature and with 50,000 flexes at -10 ° C far above the requirements of genuine leather.

According to the invention, the best properties in terms of flex life, puncture and tear strength, softness and flexural strength are achieved when for the layer 1'' and for the lower class 3 Dispersions are used which have a preferred Shore A hardness between 2 and 15 Shore A and if this layer 1'' and layer 3 deep in the carrier or in the middle class 2 protrude or meet there. At the same time, the elongation at break of the middle class becomes 2 not reduced, in contrast to dispersions which have a Shore A hardness of more than 22 Shore A.

The contact adhesive properties of the layer 1'' can be demonstrated on the finished product, in which one layer 1 from the shift 2 separates and the layer 1'' moistened with MEK. It becomes sticky, although it is networked, as opposed to, layer 1' ,

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2012072257 A1 [0002]
• WO 2011/157279 A1 [0003]
• US 6177198 B1 [0030]

Cited non-patent literature

• DIN EN ISO 17076-2 [0005]
• DIN EN ISO 2589 [0007]
• DIN EN ISO 3376 [0007]
• DIN EN ISO 2589 [0035]
• DIN EN ISO 11644 [0059]
• DIN 53109 [0060]
• DIN EN ISO 20344 [0061]
• DIN EN ISO 5402 [0087]

Claims (34)

Leather exchange material comprising an outer layer which is in operation or in use ( 1 ), a middle layer ( 2 ) and one with this middle class ( 2 ) associated sublayer ( 3 ), characterized in that - the upper class ( 1 ) Is formed from a solidified, crosslinked PU dispersion based on aliphatic polyester and / or polyether, in particular with an amorphous structure, that the middle layer ( 2 ) - is formed from a knitted fabric or a woven fabric of polyester fibers or filaments, optionally with a proportion of 10 to 50 wt .-% of cotton and / or cellulose fibers or filaments, - wherein the knitted fabric or fabric has a basis weight of 190 to 420 g / m ² , preferably 220 to 280 g / m ² , and a thickness of 0.30 to 1.0 mm, preferably from 0.30 to 0.60 mm, in particular from 0.30 to 0.50 mm , and optionally the fabric has a breaking extension in both directions between 25 and 90%, preferably between 35 and 70%, and the fabric has an elongation at break between 75 and 450% in both directions, and 3 ) - is formed from a foamed plastic, which in liquid or pasty form on the middle layer ( 2 ) was applied or - from a plastic dispersion, in particular a solidified amorphous, crosslinked, aliphatic or aromatic PUR dispersion, formed with the middle layer ( 2 ) and, if appropriate, that of the middle class ( 2 ) side facing away from the lower layer ( 3 ) with an outer layer ( 12 ) connected is. Leather exchange material according to claim 1, characterized in that both the upper layer ( 1 ) as well as the lower class ( 3 ) in one strength ( 5 . 6 ) of at least 0.050 mm into the middle layer ( 2 ) are introduced and inseparably connected with this. Leather exchange material according to claim 1 or 2, characterized in that in the middle layer ( 2 ) a layer ( 10 ) is formed with a thickness (D) free of those in the upper class ( 1 ) and the lower class ( 3 ) and whose thickness (D) at a pressure load of the leather exchange material of up to 2 kg / cm ² direct contact of upper layer ( 1 ) and sublayer ( 3 ) and prevents a gap between the upper class ( 1 ) and the lower class ( 3 ) of at least 0.15 mm or - that for the upper class ( 1 ) and into the middle class ( 2 ) penetrated solid PUR dispersion and for the lower layer ( 3 ) and into the middle class ( 2 ) penetrated solidified polyurethane dispersion in the middle region of the middle layer ( 2 ) meet. Leather exchange material according to one of claims 1 to 3, characterized in that the solidified PU dispersion of the upper layer ( 1 ) and the lower class ( 3 ) have the same or a very similar structure and / or have the same or a very similar, preferably at most 15% different, Shore A hardness. Leather exchange material according to one of Claims 1 to 4, characterized in that, at a thickness of 0.3 to 0.5, the middle layer ( 2 ) the solidified PU dispersions of the upper layer ( 1 ) and the lower class ( 3 ), preferably in the middle region of the middle layer ( 2 ), and at a greater thickness of the middle class ( 2 ) or a thickness of the middle layer exceeding the two indentation depths ( 2 ) the polymer or plastic-free layer ( 10 ) is trained. Leather exchange material according to one of claims 1 to 5, characterized in that the upper layer ( 1 ) has a thickness of 0.10 to 0.22 mm, preferably 0.12 to 0.15 mm, - and / or a Shore A hardness of 22 to 88, preferably from 45 to 65, owns - and / or has a homogeneous structure is - and / or has a density of 0.95 to 1.15 g / cm ³ . Leather exchange material according to one of claims 1 to 6, characterized in that the knitted fabric or fabric of the middle layer ( 2 ) is elastically elastic and the middle layer ( 2 ) elastically returns to its initial position up to a load of 1.0 kg / cm ² . Leather exchange material according to one of claims 1 to 7, characterized in that the lower layer ( 3 ) of a foamed, solidified plastic dispersion, for. B. an aromatic and / or aliphatic polyurethane dispersion, optionally with a maximum of 30 wt .-% polyacrylates, constructed or formed or is formed from a soft PVC foam. Leather exchange material according to one of claims 1 to 8, characterized in that the lower layer ( 3 ) optionally together with the outer layer ( 12 ) has a density of 0.30 to 0.85 g / cm ³ and / or is reversibly compressible at a load of 1 kg / cm ² by at least 25% and / or a thickness of 0.15 mm to 0.60 mm , preferably from 0.20 mm to 0.40 mm. Leather exchange material according to one of claims 1 to 9, characterized in that the lower layer ( 3 ) from a plastic Disperse foam, preferably polyurethane foam, which has open cells or is formed with a plastisol containing propellant and by solidification by heat closed cells, or is formed from a plastic dispersion containing hollow microspheres made of plastic, forming the closed cells , Leather exchange material according to one of claims 1 to 10, characterized in that in the middle layer ( 2 ) and / or in the lower class ( 3 ) flame-retardant additives are contained and / or that in the upper class ( 1 ) and / or in the lower class ( 3 ) Additives, preferably silicone emulsions and / or dispersions and / or pigments, in a total amount of up to 25 wt .-%, preferably up to 21 wt .-%, based on the total weight of the dispersion. Leather exchange material according to one of claims 1 to 11, characterized in that the upper layer ( 1 ) of several, in particular with respect to their composition, or similar, layers ( 1' . 1'' ), which are assembled into an inseparable layer, wherein the inner layer ( 1'' ) with the middle class ( 2 ) and / or introduced into this and / or that in a multi-layered upper layer ( 1 ) which are partly in the middle class ( 2 ) penetrated, inner layer ( 1'' ) has a Shore A hardness of less than 22 Shore A, preferably between 2 and 15 Shore A. Leather exchange material according to one of claims 1 to 12, characterized in that in the upper layer ( 1 ) Pores and / or capillaries are formed and / or that in the lower layer ( 3 ) Microperforations are formed, which are also covered by the upper layer ( 1 ) are continued. Leather exchange material according to one of claims 1 to 13, characterized in that the upper layer ( 1 ), the middle class ( 2 ) and the lower layer ( 3 ) has a thickness of 1.00 to 1.80 mm, preferably 1.20 to 1.50 mm, and / or has a basis weight of less than 800 g / m ² , preferably less than 700 g / m ² , has. Leather exchange material according to one of claims 1 to 14, characterized in that the lower layer ( 3 ) is formed in one or more layers and / or on its upper layer ( 1 ) surface facing away from the outer layer ( 12 ) carries a final coat of polyacrylate or polyurethane in a thickness of less than 0.01 mm. Leather exchange material according to one of claims 1 to 15, characterized in that the stitches in the middle layer ( 2 ) are close to each other and the cavities or distances between the fibers or threads smaller dimensions than 0.30 mm, in particular 0.25 mm, have. Leather exchange material according to one of claims 1 to 16, characterized in that in the lower layer ( 3 ) Hollow microspheres in an amount of 6 to 12 wt .-%, based on the weight of the polymer dispersion, are included. Leather exchange material according to one of claims 1 to 17, characterized in that the surface of the upper layer ( 1 ) has the structure of embossed nubuck leather with scarcuts and scar troughs formed on a negative template and / or that the surface of the upper layer ( 1 ) Has areas with different surface structure and / or that the valleys have a depth which is greater than the thickness of the upper layer ( 1 ). Leather exchange material according to one of claims 1 to 18, characterized in that with the solidified PUR dispersion of the lower layer ( 3 ) as outer layer ( 12 ) is bonded to a PUR film having a thickness of 0.60 to 1.20 mm, preferably 0.80 to 1.0 mm. Leather exchange material according to claim 17, characterized in that the PUR film has an open and fine-cell foam structure and / or - has a Shore A hardness of 6 to 14, preferably from 8 to 12, and / or - has a density of 0.15 to 0.32 g / cm ³ , preferably from 0.18 to 0.22 g / cm ³ , and / or - the polyurethane foam sheet is formed from one, preferably aromatic, polyether or polyester polyurethane and / or that the solidified PU dispersion of the lower layer ( 3 ) penetrated at least 0.30 mm into the open-cell PUR foam sheet. Leather exchange material according to one of claims 1 to 20, characterized in that the leather exchange material has a Shore A hardness of 25 to 60, preferably from 20 to 50, possesses. Leather exchange material according to one of claims 1 to 21, characterized in that the to the solidified PU dispersion of the lower layer ( 3 ) a textile material, preferably a nonwoven fabric or a nonwoven fabric of polyester fibers, as outer layer ( 12 ), which advantageously has a thickness between 0.6 to 1.2 mm. Leather exchange material according to claim 22, characterized in that the nonwoven fabric is a needle-punched nonwoven fabric or a spunbonded nonwoven or a nonwoven fabric solidified by sewing or embossing. Leather exchange material according to claim 22 or 23, characterized in that the nonwoven has a basis weight between 80 and 200 g / m ² . Leather exchange material according to one of claims 1 to 24, characterized in that the solidified PUR dispersion of the lower layer ( 3 ) has a Shore A hardness of 8 to 22, preferably 6 to 15. Leather exchange material according to one of claims 1 to 25, characterized in that the middle layer ( 2 ) penetrated foam of the lower layer ( 3 ) in the penetration areas has the structure of a non-foamed solidified plastic dispersion. Leather exchange material according to one of Claims 1 to 26, characterized in that the amorphous, preferably polyether-based, solidified PUR dispersion of the lower layer ( 3 ) has a basis weight of 30 to 90 g / m ² . Leather exchange material according to one of claims 1 to 27, characterized in that the leather exchange material at a thickness of 1.2 to 1.4 mm according to DIN EN ISO 3376 an elongation at break in both or in mutually perpendicular directions in each case from 38 to 300%, preferably from 45 to 220%, and / or has a basis weight of less than 700 g / m ² . Leather exchange material according to one of claims 1 to 28, characterized in that the upper layer ( 1 ) an elongation at break of more than 350% and / or that the lower layer ( 3 ) has an elongation at break between 60% and 400%. Leather exchange material according to one of claims 1 to 29, characterized in that the middle layer ( 2 ) is formed of a polyester fabric, which polyester fibers, for. B. by needling, are introduced, wherein the in particular centrally embedded in the polyester fabric fibers protrude on both sides of the polyester fabric, wherein optionally the polyester fabric with the polyester fibers, a basis weight between 200 and 300 g / cm ³ and / or a thickness between 0.5 and 0.8 mm. Leather exchange material according to claim 30, characterized in that the solidified PU dispersions of the upper layer ( 1 ) and the lower class ( 3 ) up to those in the layer ( 2 ) embedded fibers and the polyester fibers ( 13 ) into the upper class ( 1 ) and the lower class ( 3 protrude). Leather exchange material according to one of claims 1 to 31, characterized in that on the back of the outer layer formed by a PUR film ( 12 ) an additional layer of a solidified polyurethane and / or polyacrylate dispersion is applied which is at least 0.30 mm into the open cells of the outer layer ( 12 ) and optionally contains colored pigments. Leather exchange material according to one of claims 1 to 32, characterized in that the flex life of the leather exchange material according to the invention according to DIN EN ISO 5402 (Bally Flexameter) at 200,000 Flexen at normal temperature and 50,000 Flexen at -10 ° C. Use of the leather exchange material according to any one of claims 1 to 33 for the interior decoration or lining of the interior walls of vehicles, for shoes, for bags or for handbags and for sheet or plate goods and trim for shoes, bags and car interior trim.

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