LAYER COMPOSITE FOR USE AS IMITATION LEATHER

Description

SUBJECT OF THE INVENTION

[0001] The invention relates to a layered composite for use as imitation leather, a process for producing the layered composite, and uses of the layered composite. BACKGROUND OF THE INVENTION

[0002] The leather industry is one of the sectors with the highest potential for environmental pollution. The chemicals used in tanning, particularly antibiotics, tanning agents, biocides, and volatile organic chemicals such as formaldehyde, can cause lasting environmental damage if not used properly. However, proper use of these chemicals is costly and time-consuming. Furthermore, some of the substances used can remain in the material and only leach out during later use. This poses health risks for the end consumer. Furthermore, there are also ethical concerns regarding the use of animal hides.

[0003] Therefore, there have long been efforts to replace leather with synthetic materials. These substitutes are generally referred to as synthetic leather. This is usually a composite of a textile base and a plastic layer applied to it, such as polyvinyl chloride (PVC) or polyurethane (PU).

[0004] DE 1 635 546 A describes an artificial leather produced by papermaking processes, wherein the artificial leather consists essentially of non-fibrous elastomeric polyurethane with minor admixtures of staple fibers, preferably synthetic fibers or leather fibers.

[0005] DE 199 37 808 A1 relates to a leather substitute material comprising a substantially fabric-like carrier layer, a thinner barrier layer applied thereto and a covering layer provided on the barrier layer.

[0006] GB 2 010 750 A relates to a decorative article comprising at least one layer of sheet material and one layer of a fibrous reinforcing material. The two layers are sandwiched between translucent layers of a cured synthetic resin matrix.

[0007] WO 2007 / 091770 A1 relates to an interior wall covering comprising: a multi-layer fabric consisting of a plurality of stacked thin layers of combed cotton fibers and a resin layer applied to a surface of the fabric, which resin layer consists of acrylic resin, EVA resin or biodegradable EVA resin.

[0008] DE 10 2006 001 095 A relates to a method for producing a leather-containing fabric with a cover layer and a carrier layer. It is characterized in that fine leather particles impregnated with a binder are applied to the carrier layer as a cover layer, and the binder is applied to the carrier layer to bond the leather particles. After the binder-impregnated, fine leather particles are applied to the carrier layer, textile fibers are applied to this layer, and the leather-containing fabric is needled using the textile fibers.

[0009] CN 203 198 318 U relates to a resin-coated floral synthetic leather comprising a body, characterized in that the body consists of four layers of different materials. The bottom layer of the body forms a base layer, to the upper end of which an adhesive layer is applied. On the upper side of the adhesive layer is a floral layer, which is coated with a resin layer at its upper end.

[0010] DE 10 2015 101 331 A1 relates to a translucent synthetic leather with a textile carrier structure and at least one layer of PU or PVC. The layered composite may also have a surface coating.

[0011] The synthetic leather obtained through these processes offers several advantages over animal leather. PVC synthetic leather is inexpensive and robust, whereas PU synthetic leather offers advantageous material properties such as repeated washability. Since synthetic leather is produced as a continuous material, cutting is also much easier than with animal leather. The manufacturing process is also considerably shorter, as the complex tanning process is eliminated. Furthermore, synthetic leather manufacturers are not tied to the market availability of specific animal hides.

[0012] However, previously available artificial leather materials are primarily based on synthetic plastics made from finite fossil resources such as petroleum and are not biodegradable. Furthermore, such artificial leather materials typically contain solvent or dispersant residues and plasticizers, making them potentially hazardous to health. Furthermore, artificial leather often cannot achieve the same visual and tactile properties as animal leather. TASK

[0013] Against this background, the object of the invention was therefore to provide an artificial leather which has comparable or better optical and haptic properties than synthetic leather, can be produced in a more environmentally friendly or sustainable manner than natural and / or synthetic leather and which is at least partially biodegradable. DESCRIPTION OF THE INVENTION

[0014] This object is achieved according to the invention by a layered composite for use as imitation leather, which has the following layers: a) a carrier layer comprising textile material, b) a decorative layer, c) a covering layer comprising a plastic, wax or protein material or a mixture of the above, wherein the decorative layer is arranged between the textile carrier layer and the cover layer, and wherein the decorative layer comprises or consists of plant leaf material, preferably tobacco, wherein the plant leaf material is whole or shredded treated leaves, wherein "treated leaves" is understood to mean plant leaves or shredded sections thereof that have been preserved by fermentation or chemical treatment, in particular with alcohols.

[0015] For the purposes of the invention, "plant leaf material" refers to whole or shredded, untreated or treated leaves, in particular leaf dust. In a preferred embodiment, the plant leaf material is fermented, i.e., it has undergone a fermentation process that renders the dried leaves suitable for storage and consumption.

[0016] Alternatively or additionally, the plant leaf material can be chemically treated, preferably with a mixture of water and a polyhydric alcohol such as glycerin. This gives the plant leaf material elastic deformability and increased breaking strength, in particular increased tensile strength and flexural strength. Furthermore, it has been found that the plant leaf material, even in the layered composite, can continue to undergo a maturing process which improves the deformability and breaking strength of the material. The maturing process lasts at least one week, preferably two weeks, more preferably one month, and most preferably two months. An improvement in the properties through the maturing process is particularly achieved when the covering layer comprises or consists of a wax material.

[0017] The decorative layer with plant leaf material essentially performs optical and tactile functions within the composite layer. Depending on the plant leaf material and the top layer applied to it, the decorative layer not only lends the composite layer a good grip and an appealing appearance but also a pleasant fragrance. This effect can be particularly enhanced by partially or fully needle-punching the individual layers of the composite rather than gluing and / or pressing them together. This results in increased permeability of the composite layer.

[0018] In a preferred embodiment of the invention, the decorative layer is essentially free of wood fibers. Within the scope of the present invention, this means that the proportion of wood fibers, for example, material from wood chips, sawdust, logs, and branches, is less than 5%, preferably less than 1%, even more preferably less than 0.5%, and most preferably less than 0.1%.

[0019] The plant leaf material is particularly preferably selected from the group consisting of rose petals, vine leaves, cherry laurel leaves, and tobacco. The plant leaf material is particularly preferably tobacco. In a preferred embodiment, the plant leaf material can be strip tobacco.

[0020] Tobacco offers several advantages over other plant leaf materials. As a raw material, it is readily available year-round. Due to declining demand for tobacco, there is generally excess production capacity, which can be acquired inexpensively. Furthermore, tobacco contains a high proportion of natural alkaloids, particularly nicotine, which act as insecticides. This keeps mites and other pests away from the laminated material, creating a particularly durable imitation leather. Furthermore, tobacco leaves, especially after treatment with a mixture of water and a polyhydric alcohol, exhibit particularly high flexibility and tear resistance. In addition to its visual qualities, its natural scent also speaks in favor of using tobacco as a decorative layer in imitation leather. These advantageous properties are particularly pronounced in fermented tobacco.

[0021] In addition, tobacco also exhibits moisture-regulating properties, making the laminated composite highly comfortable to wear when used as imitation leather. This effect is particularly pronounced when the laminated composite is partially or fully needled, as this results in a high level of permeability of the material.

[0022] In a preferred embodiment, the plant leaf material is dyed with a synthetic or, preferably, natural dye. This allows the optical properties of various animal leathers to be imitated. In a particularly preferred embodiment of the invention, the dye is partially or completely food-safe and / or consists of substances that can be returned to biological cycles as biological nutrients or continuously maintained in technical cycles as technical nutrients (cradle-to-cradle certification).

[0023] The carrier layer determines the structural strength of the composite and ensures good processability, particularly when the layered composite is sewn together.

[0024] In a preferred embodiment, the textile carrier layer comprises or consists of a material selected from the group consisting of nonwovens, woven fabrics, knitwear, braids or mixtures of the aforementioned.

[0025] Nonwovens, woven fabrics, knitwear, braids or mixtures of the above are textile materials that are made up of fibres but differ from one another in the arrangement of the fibres.

[0026] According to the invention, a nonwoven is understood to be a structure made of fibers of limited length, continuous fibers (filaments), or cut yarns of any type and origin, which have been combined in any way to form a fiber layer and bonded together in any way. This excludes the crossing or entanglement of yarns, as occurs in weaving, knitting, lacemaking, braiding, and the manufacture of tufted products. This definition corresponds to the DIN EN ISO 9092 standard. According to the invention, the term "nonwoven" also includes felt materials. Films and papers, however, are not considered nonwovens.

[0027] The nonwovens are preferably anisotropic nonwovens, i.e., those with fiber orientation. This allows for an anisotropic mechanical behavior of the layered composite to be created, thereby increasing its tear resistance.

[0028] According to the invention, a fabric is understood to be a textile fabric consisting of two thread systems, warp (warp threads) and weft (weft threads), which, viewed on the fabric surface, intersect in a pattern at an angle of exactly or approximately 90°. Each of the two systems can be composed of several warp or weft types (e.g., ground, pile, and filling warp; ground, binding, and filling weft). The warp threads run in the longitudinal direction of the fabric, parallel to the fabric edge, and the weft threads run in the transverse direction, parallel to the fabric edge. The threads are connected to the fabric primarily by friction. In order for a fabric to be sufficiently slip-resistant, the warp and weft threads must usually be woven relatively tightly. Therefore, with few exceptions, the fabrics also have a closed appearance. This definition corresponds to the standard DIN 61100, Part 1.

[0029] According to the invention, the terms woven and nonwoven also include tufted textile materials. Tufting is a process in which yarns are anchored into a woven or nonwoven fabric using a machine powered by compressed air and / or electricity.

[0030] According to the invention, knitwear refers to textile fabrics made from thread systems by stitch formation. This includes both crocheted and knitted fabrics.

[0031] For the purposes of the invention, braiding refers to the regular interlacing of several strands of flexible material. The difference from weaving is that in braiding, the threads are not fed at right angles to the main product direction.

[0032] The fibers of nonwovens, woven fabrics, knitwear, braids or mixtures thereof may be natural fibers, chemical fibers or mixtures of the above.

[0033] Preferably, the fibers are of plant or animal origin, or chemical fibers made from natural polymers or polymers based on natural raw materials. This can improve the proportion of natural components in the composite layer and thus its sustainability and biodegradability.

[0034] The natural fibers are preferably selected from the group consisting of seed fibers, bast fibers, leaf fibers, and animal fibers. They are particularly preferably selected from the group consisting of cotton, animal wool, animal hair, silk, kapok, akon, poplar fluff, bamboo fiber, fiber nettle, hemp, hemp nettle, jute, urena, linen, ramie, kenaf, roselle, sunns, abutilon, pung, castor bean, sisal, abaca, curaua, fibe, ixtle fiber, arenga, afrik, hequen, fique, phormium, alfa, maguey, yucca, pita, coconut, broom, hops, cattail, and bast.

[0035] The chemical fibers are preferably selected from natural polymers or polymers based on natural raw materials. Particularly preferably, they are selected from the group consisting of viscose, modal, lyocell, curpo, cellulose acetates, protein fibers such as casein fibers, polylactides, alginates, chitin, bio-based polyamides, polyesters, and polyisoprenes.

[0036] In a further embodiment, the chemical fibers made of synthetic polymers are selected from the group consisting of polyesters such as PET or PBT, polyamide, polyimide, polyamideimide, aramid, poly(metha)acrylates, modyacryl, polytetrafluoroethylene (PTFE), polyethylene, polypropylene, polychloride, PVC, elastane, polystyrene, polycarbonate, polyvinyl alcohol, vinylal, polyphenyl sulfide, melamine, polyurea, polyurethane, polybenzimidazole, polybenzoxal.

[0037] In a preferred embodiment, the thickness of the textile carrier layer is 0.1 to 10 mm, more preferably 0.1 to 5 mm, particularly preferably 0.1 to 2 mm, most preferably 0.2 to 1 mm.

[0038] In a preferred embodiment, the basis weight (grammage) of the carrier layer is 50 to 200 g / m 2 , more preferably 65 to 130 g / m 2 , particularly preferably 80-120 g / m 2 , most preferably 90-110 g / m 2 . A low basis weight allows for the production of particularly lightweight layered composites.

[0039] In a preferred embodiment, the plant leaf material of the decorative layer is finely ground tobacco and / or tobacco dust and / or tobacco clippings, wherein the plant leaf material is preferably bound in the decorative layer by a polysaccharide. In a preferred embodiment of the invention, the polysaccharide is dissolved or suspended in a solvent or dispersant containing or consisting of a polyhydric alcohol such as glycerin prior to formation of the decorative layer.

[0040] In another preferred embodiment, plant leaves and / or sections and / or panicles are the plant leaf material of the decorative layer. Such a decorative layer lends the layered composite a particularly natural and elegant appearance and can therefore also be referred to as a finishing layer. Similar to animal crocodile or snakeskin, such a decorative layer creates a unique, ever-changing, and vibrant appearance of the layered composite. To achieve particularly good visual and tactile properties of the composite, in a preferred embodiment of the invention the leaves are laid overlapping. This creates a decorative layer with sections of varying thickness. These "irregularities" in the layered composite give the user the impression of a particularly natural imitation leather.

[0041] In a further preferred embodiment, the plant leaf material of the decorative layer is strip tobacco. According to the invention, strip tobacco refers to a film in which pressed tobacco waste, tobacco dust, ground tobacco leaves and / or stems are blended with a binding agent, usually cellulose and polysaccharide derivatives, or applied to fibrous cellulose carrier materials coated with setting agents and processed into a flat, endless strip of virtually uniform thickness and quality. Treating the strip tobacco with a mixture of water and a polyhydric alcohol, especially glycerin, has proven particularly advantageous.

[0042] Strip tobacco offers the advantage of particularly good availability at low purchase prices. Furthermore, the use of strip tobacco allows for the creation of a particularly homogeneous decorative layer. This can be advantageous in some applications of the layered composite, for example, when a particularly uniform color is desired.

[0043] In a preferred embodiment, the thickness of the decorative layer is 0.1 to 10 mm, more preferably 0.1 to 5 mm, particularly preferably 0.1 to 2 mm, most preferably 0.2 to 1 mm.

[0044] In a preferred embodiment, the basis weight (grammage) of the decorative layer is 40 to 150 g / m 2 , more preferably 65 to 120 g / m 2 , particularly preferably 70 to 100 g / m 2 , most preferably 80 to 100 g / m 2 . A low basis weight allows for the production of particularly lightweight layered composites.

[0045] The top layer of the laminate comprises or consists of a plastic, wax, or protein material, or a mixture of the aforementioned. Its primary purpose is to protect the underlying decorative layer from external influences such as moisture, abrasion, and / or radiation.

[0046] When very high demands are placed on strength, water resistance, and abrasion resistance, plastic materials are preferred. According to the invention, this refers to all materials consisting of macromolecules of natural or synthetic origin.

[0047] In a preferred embodiment, the plastic comprises or consists of a material selected from the group consisting of polypropylene (PP), polyethylene (PE), polyvinyl butyral (PVB), polyamide (PA), polyester, in particular polybutylene terephthalate (PBT) and polyethylene terephthalate (PET), polyurethane (PU), polyethylene oxides, polyphenylene oxides, thermoplastic polyurethanes (TPU), polyurea, polyacetal, polyacrylate, poly(meth)acrylates, polyoxymethylene (POM), polyvinyl acetal, polystyrene (PS), acryloyl-butadiene-styrene (ABS), acrylonitrile-styrene-acrylate (ASA), polysaccharides, in particular pectin and agar-agar, polycarbonates, polyethersulfones, polysulfonates, polytetrafluoroethylene (PTFE), polyurea, formaldehyde resins, melamine resins, polyether ketone, polyvinyl chloride, polylactide, polysiloxane, phenolic resins, Epoxy resins, poly(imide), bismaleimide triazine, thermoplastic polyurethane, ethylene-vinyl acetate copolymer (EVA), polylactide (PLA),Polyhydrobutyric acid (PHB), copolymers and / or mixtures of the aforementioned polymers. Particularly preferred are PE, PET, PU and PA.

[0048] The plastic is preferably used in the form of a film. According to the invention, this refers to a flat plastic material produced in webs with a layer thickness of < 5 mm, preferably < 1 mm.

[0049] If high demands are placed on feel, smell and appearance, a decorative layer made of protein material or wax is preferred.

[0050] Wax, as defined in the present invention, refers to natural or synthetically obtained substances that are malleable at 20°C, solid to brittle-hard, have a coarse to finely crystalline structure, are translucent to opaque in color but not glassy, ​​melt above 40°C without decomposition, are slightly liquid (i.e., slightly viscous) slightly above the melting point, have a highly temperature-dependent consistency and solubility, and are polishable under light pressure. This corresponds to the definition in the Römpp Chemie Lexikon, 10th edition, 1999, Georg Thieme Verlag.

[0051] Waxes can be divided into natural waxes, chemically modified waxes, and synthetic waxes. In a preferred embodiment of the invention, the wax material is selected from the group of natural waxes, particularly preferably from the group of vegetable waxes, in particular candelilla wax, carnauba wax, Japan wax, esparto grass wax, cork wax, guaruma wax, rice germ oil wax, sugar cane wax, ouricury wax, and montan wax.

[0052] In another preferred embodiment, the natural wax is selected from the group consisting of animal waxes and mineral waxes, in particular from the group consisting of beeswax, shellac wax, spermaceti, lanolin (wool wax), rump grease, ceresin, ozokerite (earth wax).

[0053] Natural waxes offer the advantage that they are not petroleum-based and thus contribute to the sustainability and biodegradability of the layer composite.

[0054] In another embodiment, the wax is selected from the group consisting of chemically modified waxes or synthetic waxes, in particular from the group selected from montan ester waxes, sasol waxes, paraffins, hydrogenated jojoba waxes, polyalkylene waxes, polyethylene glycol waxes.

[0055] In a further preferred embodiment, the cover layer of the laminate comprises or consists of a protein material. These are preferably proteins of plant origin. Proteins found in lupin, soy, peas, linseed, wheat, corn, and / or rapeseed are particularly preferred.

[0056] In a further embodiment, the proteins are of animal origin, with gelatin, casein, whey proteins and / or their derivatives being particularly preferred.

[0057] The advantage of a protein top layer is that the production costs are very low and that it is harmless to health. The layer can also be processed without organic solvents, i.e., it is water-based. It is also worth emphasizing that the protein top layer is made from renewable raw materials that are biodegradable and self-adhesive.

[0058] In a preferred embodiment, the thickness of the cover layer is 5 µm-1 mm, more preferably 10 µm to 0.5 mm, particularly preferably 20 µm to 0.1 mm, most preferably 50 µm to 0.1 mm.

[0059] The top layer may also contain additives such as dyes, UV filters, binders, or fillers. The addition of additives and fillers can alter the properties of the top layer, particularly its color, strength, and manufacturing price.

[0060] The additives are preferably selected from the group consisting of calcium carbonate, chemical and physical UV filters such as titanium dioxide, calcium and barium sulfate, aluminum hydroxide, silicates such as talc, clay or mica, kaolin or wolastonite, glass fibers, dyes, silica, glass fibers and glass beads as well as cellulose powder, carbon black and graphite.

[0061] In a preferred embodiment, the layered composite comprises the following layers: a) a carrier layer consisting of textile material, b) a decorative layer consisting of plant leaf material, c) a covering layer consisting of a plastic, wax or protein material or a mixture of the above, wherein the decorative layer is arranged between the textile carrier layer and the cover layer.

[0062] In a further preferred embodiment, the layer composite has the following layers: a) a carrier layer consisting of textile material, b) a decorative layer consisting of plant leaf material, c) a covering layer comprising a plastic, wax or protein material or a mixture of the above,

[0063] In a further preferred embodiment, the layer composite has the following layers: a) a carrier layer consisting of textile material, b) a decorative layer comprising plant leaf material, c) a covering layer comprising a plastic, wax or protein material or a mixture of the above, wherein the decorative layer is arranged between the textile carrier layer and the cover layer.

[0064] In another preferred embodiment, the layer composite consists of the following layers: a) a carrier layer consisting of textile material, b) a decorative layer consisting of plant leaf material, c) a covering layer consisting of a plastic, wax or protein material or a mixture of the above, wherein the decorative layer is arranged between the textile carrier layer and the cover layer.

[0065] In another preferred embodiment, the layered composite comprises the following layers: a) a carrier layer consisting of textile material, b) a decorative layer consisting of tobacco, c) a covering layer consisting of a plastic, wax or protein material or a mixture of the above, wherein the decorative layer is arranged between the textile carrier layer and the cover layer.

[0066] In a further preferred embodiment, the layer composite has the following layers: a) a carrier layer consisting of textile material, b) a decorative layer consisting of tobacco, c) a covering layer comprising a plastic, wax or protein material or a mixture of the above,

[0067] In a further preferred embodiment, the layer composite has the following layers: a) a carrier layer consisting of textile material, b) a decorative layer comprising tobacco, c) a covering layer comprising a plastic, wax or protein material or a mixture of the above, wherein the decorative layer is arranged between the textile carrier layer and the cover layer.

[0068] In another preferred embodiment, the layer composite consists of the following layers: a) a carrier layer consisting of textile material, b) a decorative layer consisting of tobacco, c) a covering layer consisting of a plastic, wax or protein material or a mixture of the above, wherein the decorative layer is arranged between the textile carrier layer and the cover layer.

[0069] In a particularly preferred embodiment, the layer composite consists of a carrier layer made of flax fleece or a fabric, a decorative layer made of the plant material tobacco and a cover layer made of a plastic, wax or protein material, preferably of polyethylene, polyethylene terephthalate, polyurethane, polyamide or a mixture of the aforementioned plastics.

[0070] The layered composite may comprise additional layers. These are preferably selected from the group consisting of carrier, decorative, adhesive, and cover layers. Particularly preferably, the layered composite comprises one or more additional decorative layers arranged between the carrier and cover layers. In a preferred embodiment, the additional layers are arranged on both sides of the carrier layer. Particularly preferred in this context is the symmetrical arrangement of the layers in relation to the carrier layer, for example, a layer sequence: 1st cover layer, 1st decorative layer, carrier layer, 2nd decorative layer, 2nd cover layer.

[0071] In a preferred embodiment of the invention, the laminated composite comprises only adhesive layers as additional layers. In another preferred embodiment, the laminated composite comprises no additional layers other than carrier, decorative, and cover layers.

[0072] In a preferred embodiment, the individual thicknesses of these additional layers are 0.1 to 10 mm, more preferably 0.5 to 8 mm, particularly preferably 1 to 5 mm, most preferably 2 to 4 mm.

[0073] In a preferred embodiment, the basis weight (grammage) of the additional layers is 50 to 200 g / m 2 , more preferably 65 to 130 g / m 2 , particularly preferably 80 to 120 g / m 2 , most preferably 90 to 110 g / m 2 . A low basis weight allows for the production of particularly lightweight layered composites.

[0074] In a preferred embodiment, the layered composite may comprise one or more adhesive layers. The adhesive of the adhesive layers may be chemically curing and / or physically setting.

[0075] The adhesive of the adhesive layers is preferably selected from the group consisting of cyanoacrylates, methyl methacrylates, unsaturated polyesters, dispersion adhesives, solvent- or dispersion-containing wet adhesives, protein-based adhesives, hot melt adhesives, plastisols, epoxy adhesives, polyurethane adhesives, silicones, resins, in particular phenolic resins, polyimides, polysulfides, poly(meth)acrylates, polyvinyl acetates, rubbers and bismaleimides.

[0076] In order to produce the material in the most environmentally friendly way possible, protein adhesives are particularly preferred.

[0077] The adhesive is preferably cured by chemical curing or solidification through cooling. This allows for the use of small amounts of solvents or dispersants, or even eliminates them entirely. This is not only particularly sustainable, but also generally improves processing times and bonding within the layered composite.

[0078] In a further advantageous embodiment, the strength, in particular the tensile strength and / or the flexural strength, of one, several or all cover and / or carrier layers is greater than that of the at least one decorative layer.

[0079] Tensile strength, also known as tear strength, is the maximum tensile stress a body can withstand. It can be determined through a tensile test.

[0080] Flexural strength is the maximum tensile stress a body can withstand when subjected to bending. It can be determined using a 3- or 4-point bending tensile test.

[0081] If, in an advantageous embodiment, the strength, in particular the tensile strength and / or flexural strength, of one, several or all cover and / or carrier layers is greater than that of the at least one decorative layer, the carrier and / or cover layers can absorb the stresses arising under mechanical stress, so that the at least one decorative layer does not break or only breaks under greater stress, which would result in disadvantageous cracks in the layer determining the appearance.

[0082] The elasticity of the decorative layer, and thus its strength, can be increased by fermentation and / or chemical treatment of the plant material. Treating fermented leaves with a mixture of water and a polyhydric alcohol, especially glycerin, has proven particularly advantageous.

[0083] Tobacco leaves are particularly suitable for this purpose, as they naturally have good moisture-regulating properties and are not prone to breaking.

[0084] The invention also includes a method for producing the layered composite, which comprises the following steps: A) applying a plant leaf material to a carrier or a cover layer so that a decorative layer is formed which preferably covers ≥ 90% of a flat side of the carrier or the cover layer, B) applying a cover layer made of a plastic, wax or protein material or a mixture of the aforementioned to the decorative layer if the decorative layer was applied to a carrier layer in step A), or applying a carrier layer if the decorative layer was applied to a cover layer in step A).

[0085] According to the invention, application refers to the creation of a solid bond between the layers. This can be achieved, for example, by gluing, curing a layer, needling, or 3D printing.

[0086] In a preferred embodiment of the invention, a transfer film is used in the manufacturing process.

[0087] In a preferred embodiment of the invention, in step A) the plant leaf material is applied to a carrier layer and in step B) the cover layer is applied to the decorative layer.

[0088] In another preferred embodiment of the invention, in step A) the plant leaf material is applied to a cover layer and in step B) the carrier layer is applied to the decorative layer.

[0089] In a preferred embodiment, a pre-cured layer, such as a plastic film, can be applied to the decorative layer. This can be achieved, for example, by applying adhesive to the decorative layer and / or the plastic film, placing the film on the decorative layer, and pressing the layers together, preferably under pressure. Alternatively and / or additionally, the cover layer can be needle-punched to the decorative layer.

[0090] In a particularly preferred embodiment of the method, a polyethylene layer is glued onto the decorative layer in a laminating plant for paper products.

[0091] In another embodiment of the invention, a composition that is yet to be cured can be applied to the decorative layer, from which the cover layer is formed. For example, one or more waxes can be applied to the decorative layer, which then cure on the decorative layer.

[0092] The curing of the composition and the formation of the top layer can also occur under the influence of elevated temperatures, pressure and / or radiation.

[0093] In another embodiment of the invention, the layers are additionally needled. Needled-punching the layers has the advantage of significantly increasing permeability, for example, to gases such as water vapor.

[0094] Since the carrier layer is usually supplied as a continuous web, the production of the layer composite can take place in a continuous process, which represents a significant advantage over the discontinuous process of animal leather production.

[0095] The topcoats commonly used in the textile sector for screen printing have also been successfully tested. Topcoats produced from water-based mixed systems for textile printing are particularly preferred in this context. These water-based mixed systems comprise a water-based binder, in particular a synthetic resin dispersion binder, which preferably has a transparency of ≥ 80% and / or contains additional components such as pigments, adhesion promoters, or fillers. Water-based mixed systems that are free of organic solvents or dispersants, phthalates, formaldehyde, alkylphenols, and alkylphenol ethoxylates are particularly preferred. The water-based mixed systems are preferably non-hazardous, non-toxic, and skin-friendly.

[0096] After application to the decorative layer, the water-based mixed systems are preferably dried with heat and then heat-set at a temperature of 150-160°C. Setting can be done with a transfer press, a drying tunnel, a hot air gun, an iron, a press, or in an oven. The setting time at the above temperatures is 2-3 minutes.

[0097] In a particularly preferred embodiment, the manufacturing process is carried out as follows. First, the carrier layer is transported through rollers. In a first section, the adhesive is applied. In a subsequent section, the adhesive-coated plant leaves are applied. In a subsequent section, the plant leaves are pressed onto the substrate by a heated calender or pressure rollers. In a further section, the cover layer is applied. If the cover layer is a plastic material in the form of a film, it can be applied using a heated calender.

[0098] In a preferred embodiment of the invention, the method comprises the following additional method steps: C) Dispersing the plant leaf material in an aqueous solvent or dispersant before application to the carrier or cover layer, wherein the plant material is preferably tobacco, D) Removing the aqueous solvent or dispersant of the dispersion after application of the dispersion to the carrier or cover layer, preferably at elevated temperature and / or reduced pressure, so that the decorative layer is formed. Optional: E) Needling and / or gluing at least two layers of the composite layer.

[0099] In a preferred embodiment, steps A) to E) are carried out in the order A), B), C), D), E).

[0100] In a preferred embodiment of the method, adhesive is applied to the plant leaf material and / or the carrier layer before applying the plant leaf material to the textile carrier layer. This allows a particularly strong bond between the carrier and decorative layers to be achieved.

[0101] In a preferred embodiment of the method, the layers of the composite are pressed under increased pressure, wherein the pressing takes place in a transfer press and / or using elevated temperatures.

[0102] In a preferred embodiment of the process, the aqueous solvent or dispersant comprises a binder selected from the group consisting of polysaccharides, in particular agar agar, pectin, xanthan, natural and synthetic resins, gelatin, alginate, chitosan, cellulose ether, modified starch, glue or mixtures of the aforementioned

[0103] The binder serves to increase the viscosity of the dispersion during the manufacturing process. This allows it to be applied more effectively to the carrier layer. After the manufacturing process, the binder, which remains in the decorative layer, ensures a better bond between the plant leaf material. This effect is particularly pronounced when the solvent or dispersant is a mixture of water and a polyhydric alcohol, especially glycerin.

[0104] In a preferred embodiment of the process, the aqueous solvent or dispersant therefore comprises an alcohol, preferably a polyhydric alcohol such as glycerol, glycol, polyethylene glycol or polyethylene oxide.

[0105] The invention further encompasses various uses of the layer composite according to the invention.

[0106] The composite layer is stable, lighter than animal leather, scratch-resistant, and water-repellent. Therefore, it is ideally suited for use as a material for clothing and fashion accessories. Clothing, according to the invention, refers to all materials that more or less tightly surround the human body as an artificial covering. This also includes headwear, especially hats, and shoes. Fashion accessories, according to the invention, are accessories for clothing. These are preferably belts, gloves, fans, parasols or umbrellas, bags, scarves, and jewelry, especially watch straps.

[0107] The composite layer can also be used for coverings and upholstery.

[0108] In a preferred embodiment, the cover layer of the laminate has a transmission in the visible wavelength range of ≥ 30%, preferably ≥ 50%, more preferably ≥ 70%, and most preferably ≥ 90%. This allows the optical properties of the tobacco to be particularly well emphasized.

[0109] In a further preferred embodiment, the transmission of both the textile carrier layer and the cover layer in the visible wavelength range is ≥ 30%, preferably ≥ 50%, more preferably ≥ 60%, and most preferably ≥ 80%. This results in a layered composite that can be backlit particularly well and can thus be used in various applications in the lighting sector, for example, as a lampshade or in the interior of a motor vehicle. EXAMPLES

[0110] The invention will now be further explained using specific embodiments of layered composites, a manufacturing example, and the attached figures. These layered composites do not contain any treated sheet material and are therefore reference examples.

[0111] In the following versions, the laminated composite comprises layers containing the materials listed in the respective cells. The layers comprise or consist of the material listed in the respective cells. 1. Versions with different carrier layers

[0112] # Carrier layer decorative layer Top layer T1 fleece tobacco PE / PP / PET / PU / PA T2 fleece tobacco wax T3 fleece tobacco Protein material T4 flax fleece tobacco PE / PP / PET / PU / PA T5 flax fleece tobacco wax T6 flax fleece tobacco Protein material T7 tissue tobacco PE / PP / PET / PU / PA T8 tissue tobacco wax T9 tissue tobacco Protein material T10 Natural fiber fabric tobacco PE / PP / PET / PU / PA T11 Natural fiber fabric tobacco wax T12 Natural fiber fabric tobacco Protein material T13 Synthetic fiber fabric tobacco PE / PP / PET / PU / PA T14 Synthetic fiber fabric tobacco wax T15 Synthetic fiber fabric tobacco Protein material T16 Knitted fabric tobacco PE / PP / PET / PU / PA T17 Knitted fabric tobacco wax T18 Knitted fabric tobacco Protein material 2. Versions with different decorative layers

[0113] # Carrier layer decorative layer Top layer D1 flax fleece rose petals PE / PP / PET / PU / PA D2 tissue rose petals PE / PP / PET / PU / PA D3 Knitted fabric rose petals PE / PP / PET / PU / PA D4 flax fleece vine leaves PE / PP / PET / PU / PA D5 tissue vine leaves PE / PP / PET / PU / PA D6 Knitted fabric vine leaves PE / PP / PET / PU / PA D7 flax fleece rose petals wax D8 tissue rose petals wax D9 Knitted fabric rose petals wax D10 flax fleece vine leaves wax D11 tissue vine leaves wax D12 Knitted fabric vine leaves wax D13 flax fleece rose petals Protein material D14 tissue rose petals Protein material D15 Knitted fabric rose petals Protein material D16 flax fleece vine leaves Protein material D17 tissue vine leaves Protein material D18 Knitted fabric vine leaves Protein material 3. Versions with different cover layers

[0114] # Carrier layer decorative layer Top layer P1 flax fleece tobacco PE P2 tissue tobacco PE P3 Knitted fabric tobacco PE P4 flax fleece tobacco PP P5 tissue tobacco PP P6 Knitted fabric tobacco PP P7 flax fleece tobacco PET P8 tissue tobacco PET P9 Knitted fabric tobacco PET P10 flax fleece tobacco PU P11 tissue tobacco PU P12 Knitted fabric tobacco PU P13 flax fleece tobacco PA P14 tissue tobacco PA P15 Knitted fabric tobacco PA 4. Versions with additional layers

[0115] # Carrier layer 1. Decorative layer Additional shift Top layer F1 flax fleece tobacco Carrier layer PE / PP / PET / PU / PA F2 tissue tobacco Carrier layer PE / PP / PET / PU / PA F3 Knitted fabric tobacco Carrier layer PE / PP / PET / PU / PA F4 flax fleece rose petals Carrier layer PE / PP / PET / PU / PA F5 tissue rose petals Carrier layer PE / PP / PET / PU / PA F6 Knitted fabric rose petals Carrier layer PE / PP / PET / PU / PA F7 flax fleece tobacco Carrier layer wax F8 tissue tobacco Carrier layer wax F10 Knitted fabric tobacco Carrier layer wax F11 flax fleece rose petals Carrier layer wax F12 tissue rose petals Carrier layer wax F13 Knitted fabric rose petals Carrier layer wax F14 flax fleece tobacco Carrier layer Protein material F15 tissue tobacco Carrier layer Protein material F16 Knitted fabric tobacco Carrier layer Protein material F17 flax fleece rose petals Carrier layer Protein material F18 tissue rose petals Carrier layer Protein material F19 Knitted fabric rose petals Carrier layer Protein material F20 flax fleece tobacco decorative layer PE / PP / PET / PU / PA F21 tissue tobacco decorative layer PE / PP / PET / PU / PA F22 Knitted fabric tobacco decorative layer PE / PP / PET / PU / PA F23 flax fleece rose petals decorative layer PE / PP / PET / PU / PA F24 tissue rose petals decorative layer PE / PP / PET / PU / PA F25 Knitted fabric rose petals decorative layer PE / PP / PET / PU / PA F26 flax fleece tobacco decorative layer wax F27 tissue tobacco decorative layer wax F28 Knitted fabric tobacco decorative layer wax F29 flax fleece rose petals decorative layer wax F30 tissue rose petals decorative layer wax F31 Knitted fabric rose petals decorative layer wax F32 flax fleece tobacco decorative layer Protein material F33 tissue tobacco decorative layer Protein material F34 Knitted fabric tobacco decorative layer Protein material F35 flax fleece rose petals decorative layer Protein material F36 tissue rose petals decorative layer Protein material F37 Knitted fabric rose petals decorative layer Protein material F38 flax fleece tobacco Top layer PE / PP / PET / PU / PA F39 tissue tobacco Top layer PE / PP / PET / PU / PA F40 Knitted fabric tobacco Top layer PE / PP / PET / PU / PA F41 flax fleece rose petals Top layer PE / PP / PET / PU / PA F42 tissue rose petals Top layer PE / PP / PET / PU / PA F43 Knitted fabric rose petals Top layer PE / PP / PET / PU / PA F44 flax fleece tobacco Top layer wax F45 tissue tobacco Top layer wax F46 Knitted fabric tobacco Top layer wax F47 flax fleece rose petals Top layer wax F48 tissue rose petals Top layer wax F49 Knitted fabric rose petals Top layer wax F50 flax fleece tobacco Top layer Protein material F51 tissue tobacco Top layer Protein material F52 Knitted fabric tobacco Top layer Protein material F53 flax fleece rose petals Top layer Protein material F54 tissue rose petals Top layer Protein material F55 Knitted fabric rose petals Top layer Protein material 5. Versions with additional decorative layer of ribbon tobacco

[0116] # Carrier layer 1. Decorative layer 2. Decorative layer Top layer S1 flax fleece tobacco Band tobacco PE / PP / PET / PU / PA S2 tissue tobacco Band tobacco PE / PP / PET / PU / PA S3 Knitted fabric tobacco Band tobacco PE / PP / PET / PU / PA S4 flax fleece rose petals Band tobacco PE / PP / PET / PU / PA S5 tissue rose petals Band tobacco PE / PP / PET / PU / PA S6 Knitted fabric rose petals Band tobacco PE / PP / PET / PU / PA S7 flax fleece tobacco Band tobacco wax S8 tissue tobacco Band tobacco wax S9 Knitted fabric tobacco Band tobacco wax S10 flax fleece rose petals Band tobacco wax S11 tissue rose petals Band tobacco wax S12 Knitted fabric rose petals Band tobacco wax S13 flax fleece tobacco Band tobacco Protein material S14 tissue tobacco Band tobacco Protein material S15 Knitted fabric tobacco Band tobacco Protein material S16 flax fleece rose petals Band tobacco Protein material S17 tissue rose petals Band tobacco Protein material S18 Knitted fabric rose petals Band tobacco Protein material 6. Versions with additional layers on both sides of the carrier layer (asymmetrical)

[0117] # 1. Top layer 1. Decorative layer Carrier layer 2. Decorative layer 2. Top layer Q1 PE / PP / PET / PU / PA Band tobacco flax fleece tobacco PE / PP / PET / PU / PA Q2 PE / PP / PET / PU / PA Band tobacco tissue tobacco PE / PP / PET / PU / PA Q3 PE / PP / PET / PU / PA Band tobacco Knitted fabric tobacco PE / PP / PET / PU / PA Q4 PE / PP / PET / PU / PA Band tobacco flax fleece rose petals PE / PP / PET / PU / PA Q5 PE / PP / PET / PU / PA Band tobacco tissue rose petals PE / PP / PET / PU / PA Q6 PE / PP / PET / PU / PA Band tobacco Knitted fabric rose petals PE / PP / PET / PU / PA Q7 wax Band tobacco flax fleece tobacco wax Q8 wax Band tobacco tissue tobacco wax Q9 wax Band tobacco Knitted fabric tobacco wax Q10 wax Band tobacco flax fleece rose petals wax Q11 wax Band tobacco tissue rose petals wax Q12 wax Band tobacco Knitted fabric rose petals wax Q13 Protein material Band tobacco flax fleece tobacco Protein material Q14 Protein material Band tobacco tissue tobacco Protein material Q15 Protein material Band tobacco Knitted fabric tobacco Protein material Q16 Protein material Band tobacco flax fleece rose petals Protein material Q17 Protein material Band tobacco tissue rose petals Protein material Q18 Protein material Band tobacco Knitted fabric rose petals Protein material 7. Versions with additional layers on both sides of the carrier layer (symmetrical)

[0118] # 1. Top layer 1. Decorative layer Carrier layer 2. Decorative layer 2. Top layer M1 PE / PP / PET / PU / PA tobacco flax fleece tobacco PE / PP / PET / PU / PA M2 PE / PP / PET / PU / PA tobacco tissue tobacco PE / PP / PET / PU / PA M3 PE / PP / PET / PU / PA tobacco Knitted fabric tobacco PE / PP / PET / PU / PA M4 PE / PP / PET / PU / PA rose petals flax fleece rose petals PE / PP / PET / PU / PA M5 PE / PP / PET / PU / PA rose petals tissue rose petals PE / PP / PET / PU / PA M6 PE / PP / PET / PU / PA rose petals Knitted fabric rose petals PE / PP / PET / PU / PA M7 wax tobacco flax fleece tobacco wax M8 wax tobacco tissue tobacco wax M9 wax tobacco Knitted fabric tobacco wax M10 wax rose petals flax fleece rose petals wax M11 wax rose petals tissue rose petals wax M12 wax rose petals Knitted fabric rose petals wax M13 Protein material tobacco flax fleece tobacco Protein material M14 Protein material tobacco tissue tobacco Protein material M15 Protein material tobacco Knitted fabric tobacco Protein material M16 Protein material rose petals flax fleece rose petals Protein material M17 Protein material rose petals tissue rose petals Protein material M18 Protein material rose petals Knitted fabric rose petals Protein material Manufacturing example

[0119] 50 g of rose petals are dispersed in 50 ml of a glycerin / water solution and, after decanting the solvent or dispersant, applied to a section of flax fleece with a grammage of 100 g / m². The aqueous solvent or dispersant is removed by air drying at 50°C to obtain a uniform decorative layer. Liquid beeswax heated to 60°C is applied to this layer and allowed to cool to create a uniform covering layer. Short description of the characters:

[0120] Fig. 1: schematic sectional view of the layer composite with carrier, adhesive, decorative, 2nd adhesive, 2nd decorative and cover layer, Fig. 2: schematic sectional view of the layer composite with carrier, adhesive, decorative, 2nd adhesive and cover layer, Fig. 3: schematic sectional view of the layer composite with carrier, adhesive, decorative and cover layer, Fig. 4: schematic sectional view of the layer composite with carrier, adhesive, decorative, 2nd adhesive, 2nd decorative and cover layer, Fig. 5a / b: laying pattern of the tobacco leaves of an exemplary decorative layer. List of reference symbols:

[0121] 1Carrier layer 2Adhesive 3Band tobacco 4Adhesive layer 5Tobacco 6Adhesive layer 7Cover layer Detailed description of the characters:

[0122] Fig. 1shows the layer structure of a layered composite according to the invention, which comprises a carrier layer, adhesive layer, decorative layer, second adhesive layer, second decorative layer, and cover layer. The carrier layer 1 is bonded to the decorative layer of strip tobacco 3 by the adhesive 2. The second decorative layer 5 of tobacco is bonded to the decorative layer 3 and the cover layer 7 by the adhesive 4. The plant leaf material of the decorative layer 5 is bonded together by the adhesive.

[0123] Fig. 2 shows the layer structure of a layered composite according to the invention, which comprises a carrier layer, adhesive layer, decorative layer, second adhesive layer, and cover layer. Carrier layer 1 is bonded to decorative layer 5 by adhesive 2. Decorative layer 5 made of tobacco is bonded to decorative layer 3 and cover layer 7 by adhesive 4. The plant leaf material of decorative layer 5 is bonded together by adhesive.

[0124] Fig. 3shows the layer structure of a layered composite according to the invention, which comprises a carrier layer, adhesive layer, decorative layer, and cover layer. The carrier layer 1 is bonded to the decorative layer 5 by the adhesive 2. The decorative layer 5 made of tobacco is bonded to the decorative layer 3 and the cover layer 7 by the adhesive 4. The plant leaf material of the decorative layer 5 is bonded together by the adhesive.

[0125] Fig. 4 shows the layer structure of a layered composite according to the invention, comprising a carrier layer, adhesive layer, decorative layer, second adhesive layer, second decorative layer, and cover layer. Carrier layer 1 is bonded to the decorative layer of strip tobacco 3 by adhesive 2. The second decorative layer 5 of tobacco is bonded to the decorative layer 3 and the cover layer 7 by adhesive 4. The plant leaf material of the decorative layer 5 is bonded together by adhesive.

[0126] In Fig. 5a / 5bPossible installation patterns for the tobacco leaves are shown. The installation pattern should ensure that the carrier layer is covered by ≥ 90% of one of its flat sides, preferably completely, with leaf material.

Claims

1. Layer composite for use as imitation leather, which has the following layers: a) a carrier layer, which contains textile material, b) a decorative layer, c) a cover layer, which contains a polymer, wax or protein material or a mixture of the above-named, wherein the decorative layer is arranged between the textile carrier layer and the cover layer, wherein the decorative layer contains or consists of plant leaf material, preferably tobacco, characterized in that the plant leaf material is whole or shredded treated leaves, whereby 'treated leaves' refers to plant leaves or shredded sections thereof that have been preserved by fermentation or chemical treatment.

2. Layer composite according to claim 1, characterized in that the carrier layer contains a nonwoven fabric, preferably flax nonwoven fabric, and / or a woven fabric, preferably natural fibre, man-made fibre or mixed woven fabric.

3. Layer composite according to claims 1 to 2, characterized in that the plant leaf material of the decorative layer is finely ground tobacco and / or tobacco powder and / or tobacco offcuts, wherein the decorative layer preferably contains a binder based on a polysaccharide.

4. Layer composite according to claims 1 to 3, characterized in that the cover layer contains a polymer material, which is selected from the group consisting of polypropylene (PP), polyethylene (PE), polyvinyl butyral (PVB), polyamide (PA), polyester, in particular polybutylene terephthalate (PBT) and polyethylene terephthalate (PET), polyurethane (PU), polyethylene oxides, polyphenylene oxides, thermoplastic polyurethanes (TPU), polyurea, polyacetal, polyacrylate, poly(meth)acrylates, polyoxymethylene (POM), polyvinyl acetal, polystyrene (PS), acrylic butadiene styrene (ABS), acrylonitrile styrene acrylate (ASA), polysaccharides, in particular pectin and agar-agar, polycarbonates, polyethersulfones, polysulfonates, polytetrafluoroethylene (PTFE), polyurea, formaldehyde resins, melamine resins, polyetherketone, polyvinyl chloride, polylactide, polysiloxane, phenolic resins, epoxy resins, poly(imide), bismaleimide-triazine, thermoplastic polyurethane, ethylene-vinyl acetate (EVA), polylactide (PLA), polyhydroxybutyrate (PHB), copolymers and / or mixtures of the above-named polymers.

5. Layer composite according to claims 1 to 4, characterized in that the layer composite consists of a carrier layer made of flax nonwoven fabric or a woven fabric, a decorative layer made of the plant material tobacco and a cover layer made of a polymer, wax or protein material, preferably of polyethylene, polyethylene terephthalate, polyurethane, polyamide or a mixture of the above-named polymers.

6. Layer composite according to claims 1 to 5, characterized in that it has one or more additional decorative layers, which are arranged between carrier layer and cover layer.

7. Layer composite according to claims 1 to 6, characterized in that it has one or more adhesive layers.

8. Layer composite according to claims 1 to 7, characterized in that the tensile strength and / or the bending tensile strength of one, several or all cover and / or carrier layers is greater than that of the at least one decorative layer.

9. Method for producing a layer composite according to claims 1-8, which has the following steps: A) applying a plant leaf material, namely whole or crushed treated leaves, whereby 'treated leaves' refers to plant leaves or crushed sections thereof that have been preserved by fermentation or chemical treatment, to a carrier layer or a cover layer, with the result that a decorative layer is formed, which preferably covers ≥ 90% of a flat side of the carrier layer or the cover layer, B) applying a cover layer made of a polymer, wax or protein material or a mixture of the above-named to the decorative layer, if the decorative layer was applied to a carrier layer in step A), or applying a carrier layer, if the decorative layer was applied to a cover layer in step A).

10. Method according to claim 9, characterized in that the method has the following additional method steps: C) dispersing the plant leaf material in an aqueous solvent or dispersant before it is applied to the carrier layer or cover layer, wherein the plant material is preferably tobacco, D) removing the aqueous solvent or dispersant from the dispersion after the dispersion has been applied to the carrier layer or cover layer, preferably at increased temperature and / or decreased pressure, with the result that the decorative layer is formed. Optionally: E) needle-punching and / or gluing together at least two layers of the layer composite.

11. Method according to claims 9-10, characterized in that adhesive is applied to the plant leaf material and / or the carrier layer before the plant leaf material is applied to the textile carrier layer.

12. Method according to claims 9-11, characterized in that the layers of the composite are pressed together, wherein the pressing together is effected in a transfer press and / or using increased temperatures.

13. Method according to claims 9-12, characterized in that the aqueous solvent or dispersant contains a binder selected from the group consisting of polysaccharides, in particular agar-agar, chitosan, pectin and xanthan gum, natural and synthetic resins, gelatin, alginate, cellulose ether, modified starch, mucilage or mixtures of the above-named.

14. Method according to claims 9 to 13, characterized in that the aqueous solvent or dispersant contains an alcohol, preferably a polyvalent alcohol such as glycerol, glycol, polyethylene glycol or polyethylene oxide.

15. Use of a layer composite according to claims 1-9 for clothing and fashion accessories, in particular belts, bags and jackets.