Patent Application
20240254668
The present invention relates to a method for producing a non-synthetic textile surface structure and to the non-synthetic textile surface structure.
Leather has always been an important material for the manufacture of clothing and objects. However, real leather is generally rejected by the growing number of vegans. In addition, the use of leather has been criticized for various ecological and ethical reasons. Among other things, the production of leather causes considerable CO2 emissions during the rearing of the animals. Ecologically questionable chemicals are often used in tanneries during further processing. Although it is a by-product of the meat industry, animal suffering has become a decisive argument against leather.
For these reasons, many products that are traditionally made from or with leather are therefore offered in artificial leather (e.g. bags, furniture or car interior panels).
However, in most cases, artificial leather is based on synthetic, petroleum-based components (e.g. PU coatings, carrier materials made of synthetic fibers), which limits biodegradability and leads to other ecological problems, such as the abrasion of microplastics.
The production of artificial leather or leather-like substitutes is known in general. For example, DE 16 35 546 C3 describes a process for the production of leather-like sheet material from an aqueous slurry.
DE 10 2006 001 095 A1 goes into a similar direction, describing a process for producing a leather-containing surface structure with a top layer and a backing layer.
After these two processes, however, genuine leather is still used, at least in fiber form.
The underlying object is to provide an improved leather substitute and a suitable manufacturing process therefor.
The problem is solved by a process for producing a non-synthetic textile surface structure, comprising the steps: a) providing a pulp comprising at least one liquid, in particular water, at least one non-synthetic fiber material, at least one binder, at least one process additive; b) producing a non-synthetic textile surface structure by at least partially separating the liquid, in particular the water, from the pulp; wherein the at least one binder comprises at least one natural latex.
The method according to the invention may additionally comprise one or more of the following sub-steps in step a): a1) providing the non-synthetic fiber material, wherein the non-synthetic fiber material comprises or consists of shortened and/or un-shortened fibers; and/or a2) adding the at least one liquid, in particular water, to the non-synthetic fiber material; and/or a3) mechanical preparation of the non-synthetic fiber material; and/or a4) cleaning of the non-synthetic fiber material; and/or a5) addition of the at least one binder; and/or a6) addition of the at least one process additive; and/or a7) addition of at least one auxiliary agent; and/or a8) production of the pulp.
The method according to the invention may additionally comprise one or more of the following sub-steps in step b): b1) applying the pulp provided in step a) to a liquid-permeable carrier element, in particular a water-permeable carrier element for at least partial separation of the at least one liquid, in particular the water; and/or b2) producing a pulp layer comprising the pulp from step a), wherein the at least one liquid, in particular the water, is at least partially removed from the pulp layer; and/or b3) drying the pulp layer; and/or b4) carrying out a moulding process on the pulp layer, in particular on the dried pulp layer to obtain the non-synthetic textile surface structure; and/or b5) adding at least one auxiliary agent.
The method according to the invention can additionally comprise, during mechanical preparation in step a3), splitting the non-synthetic fiber material into fibers, or fibrillating it.
The process according to the invention may comprise the at least one process additive which is selected from the group consisting of polysaccharides, in particular starch, modified starch, cationically modified starch, cellulose or derivatives thereof, in particular carboxymethylated cellulose, cellulose acetate, hydroxypropyl methylcellulose, aluminium sulphate, or mixtures thereof.
The method according to the invention may further comprise the at least one binder, which further comprises synthetic latex.
The method according to the invention may additionally comprise at least one auxiliary agent, wherein the at least one auxiliary agent is selected from plasticizers, fillers, dyes, pigments, UV protection agents, hydrophobicizing agents, antimicrobial agents, flame retardants, wet strength agents, sizing agents or mixtures thereof.
In the process according to the invention, the non-synthetic fiber material may be selected from vegetable fiber material, preferably from natural fibers, cellulose, preferably recycled cellulose, textiles made of natural fibers, preferably from recycled textiles made of natural fibers, or mixtures thereof.
The process according to the invention may further comprise the following step: c) carrying out a post-treatment on the non-synthetic textile surface structure produced in step b).
Also according to the invention is the use of cationic starch as a process additive in the process according to the invention.
Also according to the invention is a non-synthetic textile surface structure, obtainable by the process according to the invention.
Also according to the invention is a non-synthetic textile surface structure comprising non-synthetic fiber material, at least one process additive, at least one binder, wherein the at least one binder comprises natural latex.
The non-synthetic textile surface structure according to the invention may further comprise at least one auxiliary agent selected from plasticizers, dyes, UV protection agents, hydrophobicizing agents, antimicrobial agents, flame retardants, wet strength agents, sizing agents, pigments, or mixtures thereof.
Further according to the invention is the use of the non-synthetic textile surface structure according to the invention as a leather substitute, in particular for the manufacture of fashion (shoe components, bags, accessories, clothing), furniture (seat covers, furniture surfaces), car interiors, stationery (e.g. covers), facade paneling or floor coverings.
Also according to the invention is a leather substitute comprising the non-synthetic textile surface structure according to the invention.
Furthermore, the leather substitute according to the invention comprises decorations, engravings, embossings, embroideries, coatings, adhesions, or mixtures thereof.
The object is solved by a process for producing a non-synthetic textile surface structure, comprising the steps: a) providing a pulp comprising at least one liquid, in particular water, at least one non-synthetic fiber material, at least one binder, at least one process additive; b) producing a non-synthetic textile surface structure by at least partially separating the liquid, in particular the water, from the pulp, wherein the at least one binder comprises at least one natural latex.
The method according to the invention has the advantage that a non-synthetic textile surface structure can be produced, which can be used as a leather substitute.
The term “pulp” as used in the present application refers to a fibrous, pulpy mixture, in particular a fibrous, pulpy substance, comprising at least one liquid, in particular water, at least one non-synthetic fiber material, at least one binder, in particular a plant-based binder, and at least one process additive, in particular a plant-based process additive. The pulp used in the process according to the invention is similar in its properties to the pulp known, for example, from paper production. The fiber concentration in the pulp can preferably be set to a value between 0.1% and 5% by weight.
The at least one liquid comprises water. In one embodiment, the pulp is an aqueous pulp, which means that the liquid is water. The water may be selected from distilled water or tap water or mixtures thereof. The liquid may further comprise organic solvents or oils. In one embodiment, the liquid is a mixture of water and oils. The proportion of oil in the liquid may be in the range of 10% to 30% by weight, based on the dry weight of the non-synthetic fiber material used.
The at least one non-synthetic fiber material is preferably selected from vegetable fiber material, preferably natural fibers, cellulose, preferably recycled cellulose, textiles made of natural fibers, preferably recycled textiles made of natural fibers, or mixtures thereof. In one embodiment, the non-synthetic fiber material is not present as a non-woven or woven material, but rather in the form of an accumulation of loose, isolated fibers, e.g. in the form of a bale or ball. The non-synthetic fiber material does not contain any synthetic fibers, i.e., fibers obtained from petroleum-based polymers. Furthermore, the non-synthetic fiber material does not contain any leather fibers of animal origin. This has the advantage that a non-synthetic textile surface structure can be obtained, which contains no leather fibers of animal origin, and also no fibers which have been produced from petroleum-based polymers.
Natural fibers can be by-products of agricultural products or obtained from annual plants. Examples of plants from which the natural fibers can be obtained are hemp, bananas, pineapple, silphia, flax, kenaf, jute, cotton, sisal, agave, abaca, ramie, curauá, coconut and kapok. Hemp fibers are particularly preferred according to the invention. Mixtures of the above-mentioned natural fibers can also be used. For economic and ecological reasons, it is advantageous if as non-synthetic fiber material natural fibers are used, which have been obtained as by-products of agricultural products. In this way, the CO2 balance is ceteris paribus better compared with plants that are only planted for fiber production. It is also advantageous if the value of the plant is not solely based on the fibers, and economic scaling is possible.
For the purposes of the present application, “cellulose” means a fibrous material which consists of cellulose and which results from the chemical and mechanical processing of fiber-containing plants or wood. The plants can be selected from the plants disclosed above, from which the natural fibers can also be obtained. The cellulose may also consist of recycled cellulose or at least comprise recycled cellulose.
Furthermore, the non-synthetic fiber material can be selected from textiles made from natural fibers, preferably from recycled textiles made from natural fibers, for example old clothing made from natural fibers suitable for making clothing, such as jute, cotton, sisal or hemp.
The term “binder” as used in the present application is understood to mean a substance which elastically binds fibers of the non-synthetic fiber material together to form a three-dimensional network. According to the invention, the at least one binder comprises a plant-based binder of natural latex. Natural latex can be obtained from the rubber tree (Hevea brasilensis), guayle (Parthenium argentatum), Russian dandelion (Taraxacum koksaghyz), or mixtures thereof. The latter in particular can also be cultivated in Europe, so that this raw material can be sourced regionally and thus in a more climate-friendly way. Preferably, the at least one binder consists of natural latex. In one embodiment, however, the binder can also comprise synthetic latex, which is, for example, obtained from petroleum-based polymers. By using latex or rubber, or a latex- or rubber-based binder, a leather-like, softer texture is achieved in the end product, i.e., in the leather substitute or in the non-synthetic textile surface structure according to the invention.
The term “process additive” as used in the present application refers to a precipitating agent which enables the formation of the three-dimensional network of non-synthetic fiber material and binder. The at least one process additive is selected from the group consisting of polysaccharides, in particular starch, modified starch, cationically modified starch, cellulose or derivatives thereof, in particular carboxymethylated cellulose, cellulose acetate, hydroxypropyl methylcellulose, aluminium sulphate (also called alum), or mixtures thereof. The at least one process additive is preferably a vegetable process additive selected from polysaccharides, in particular starch or cellulose or mixtures thereof. The use of polysaccharide, in particular cationic starch, has the advantage that it is at least partially water-soluble (in both cold and warm water) and develops its effect in the neutral range. The pulp is therefore no longer acidic or contaminated with acid. In addition, the use of metal salts that are harmful to health and environment is avoided. In particular, the use of cationic starch as a process additive is also in accordance with the invention, preferably in the process according to the invention.
Step a) of the method according to the invention may comprise one or more of the following sub steps:
In step a1), the non-synthetic fiber material is provided, wherein the non-synthetic fiber material comprises or consists of shortened and/or un-shortened fibers. The non-synthetic fiber material used in the process according to the invention generally has to be prepared in order to achieve a homogeneous distribution and an increased strength. Depending on the type and extraction of the non-synthetic fiber material, it must also be unravelled, for example using a carding machine. In the case of textiles, the textiles must first be chopped into small pieces, for example using a shredder.
In step a2), the at least one liquid already described above is added to the provided non-synthetic fiber material which may have passed through step a1). This can be done by placing the non-synthetic fiber material in a suitable container and then adding the liquid, or by using a reverse order. The fiber concentration can be adjusted as required. The fiber concentration may be at least 0.1 wt %, or at least 0.2 wt %, or at least 0.3 wt %, or at least 0.5 wt %, or at least 0.7 wt %, or at least 1 wt %, or at least 1.3 wt %, or at least 1.5% by weight, or at least 2% by weight, or at least 2.5% by weight, or at least 3% by weight, and/or up to 10% by weight, or up to 9% by weight, or up to 8% by weight, or up to 7% by weight, or up to 6% by weight, or up to 5% by weight, or up to 4% by weight. In particular, the fiber concentration may be at least 0.1 wt % up to 10 wt %, or 0.1 wt % up to 8 wt %, or 0.1 wt % up to 5 wt %.
In step a3), the non-synthetic fiber material is mechanically processed. The non-synthetic fiber material may have undergone at least steps a2) and a4). The term “mechanical preparation” as used in the present application means that the non-synthetic fiber material is subjected to a mechanical process comprising separating the non-synthetic fiber material into fibers and fibrillating the fibers.
In step a3), the non-synthetic fiber material is mechanically processed. The non-synthetic fiber material may have undergone at least steps a2) and a4). The term “mechanical preparation” as used in the present application means that the non-synthetic fiber material is subjected to a mechanical process comprising separating the non-synthetic fiber material into fibers and fibrillating the fibers. This has the advantage that the fiber bundles are broken down into their individual fibers, which increases the contact surface between the fibers and the binder. In this way, a more tear-resistant and homogeneous material can be formed in the subsequent process. Essentially all processes known in the prior art are suitable for this purpose. According to the invention, the non-synthetic fiber material is mechanically processed in the form of a grinding process. For this purpose, the non-synthetic fiber material is introduced into a grinding unit and subjected to a grinding process. Suitable grinding units are cone refiners, disc refiners, Holländer, Papillon refiners, PFI mills and Jokro mills. One or more grinding processes can be carried out. The grinding processes can be adjusted depending on the desired degree of grinding of the non-synthetic fiber material. Usually, a higher degree of grinding also provides a better product quality. Typically, a grinding process takes between 1 minute and 2 hours. But in principle, the duration of the grinding process depends on the targeted degree of grinding as well as the energy input (kWh/t fiber) during the grinding process. During the grinding process, the fibers are shortened, separated and fibrillated. The result is a homogeneous fiber suspension. The suspension can then be cleaned, rinsed or thickened again using a pressure screen.
In step a4), the non-synthetic fiber material is cleaned. It has been found to be advantageous for the quality and processability of the non-synthetic fiber material if the non-synthetic fiber material is freed from of foreign bodies (such as dust, splinters/woody parts, other impurities) before or after step a1) or before or after step a2) or before or after step a3). In step a4), the non-synthetic fiber material can therefore be freed from foreign bodies, in for example a mechanical way. Furthermore, the cleaning may also comprise one or more washing processes, and/or alkaline boiling and/or enzymatic treatment. For example, the non-synthetic fiber material can be boiled in an alkaline medium to break down the fibers, and to remove lignin. If the lignin remains in the non-synthetic fiber material, a natural colouring results, depending on the origin of the non-synthetic fiber material. If this natural colouring is not desired, alkaline boiling can be applied. Alkaline boiling not only removes lignin, but also reduces the strength of the non-synthetic fiber material. Purification generally has the advantage that undesirable components such as foreign bodies or interfering chemical compounds such as pectin or lignin can be at least partially, preferably completely, removed. This supports or simplifies the fibrillation in step a3) or can facilitate or accelerate the separation of the liquid in step b).
In step a5), the at least one binder can be added. For example, the binder can be provided in a suitable container, and the non-synthetic fiber material, which has optionally undergone steps a1) and/or a2) and/or a3) and/or a4) and/or a6), can be added to the binder. The sequence can also be inverse, i.e., the non-synthetic fiber material, which has optionally undergone steps a1) and/or a2) and/or a3) and/or a4) and/or a6), is placed in a suitable container and the binder is added. Binder and non-synthetic fiber material can be mixed in this step. The weight ratio of binder to non-synthetic fiber material can be varied depending on the desired property of the non-synthetic textile surface structure. For example, if more latex is used than fiber material, the result is a more rubber-like non-synthetic surface structure. Typical weight ratios of non-synthetic fiber material:latex or binder are in the range of 1:0.2 to 1:3, or 1:0.3 to 1:3, or 1:0.5 to 1:2.5, or 1:0.7 to 1:2.
In step a6), the at least one process additive can be added. The process additive can, for example, be provided in a suitable container, and the non-synthetic fiber material, which has optionally undergone steps a1) and/or a2) and/or a3) and/or a4) and/or a5), can be added to the process additive. The sequence can also be inverse, i.e., the non-synthetic fiber material, which has optionally undergone steps a1) and/or a2) and/or a3) and/or a4) and/or a5), is placed in a suitable container and the process additive added. Process additive and non-synthetic fiber material may be mixed in this step. Typical weight ratios of non-synthetic fiber material:process additive are in the range of 1:0.02 to 1:0.2, or 1:0.03 to 1:0.2, or 1:0.05 to 1:0.15.
In step a7), at least one auxiliary agent can be added. The auxiliary agent can, for example, be provided in a suitable container, and the non-synthetic fiber material, which has optionally undergone steps a1) and/or a2) and/or a3) and/or a4) and/or a5) and/or a6), can be added to the auxiliary agent. The sequence can also be inverse, i.e., the non-synthetic fiber material, which has optionally undergone steps a1) and/or a2) and/or a3) and/or a4) and/or a5) and/or a6), is placed in a suitable container, and the at least one auxiliary agent added. The auxiliary agent and the non-synthetic fiber material can be mixed in this step.
Suitable additives can be selected from plasticizers, fillers, dyes, pigments, UV protection agents, hydrophobicizing agents, antimicrobial agents, flame retardants, wet strength agents, sizing agents, or mixtures thereof.
Plasticizers are used when the non-synthetic textile surface structure according to the invention shall be more supple. Various types of plasticizers can be used according to the invention. Preferably, inorganic chemical plasticizers are avoided. In particular, plant-based plasticizers can be used, wherein the plant-based plasticizers can be selected from modified natural oils, plant-based anhydrides of alkenyl succinic acid, plant-based alkylated ketene dimers, plant-based polyhydric alcohols or mixtures thereof. The plant-based, modified oils can be sulphated. This has the advantage that these oils are easy to emulsify. In general, such natural oils can be plant-based oils, which are selected from sunflower oil, Turkish red oil (sulphated castor oil) or rapeseed oil. Furthermore, the natural oils can also be of animal origin, such as fish oil. The plasticizers, especially the modified plant-based oils, remain in the material as small droplets and thus create free spaces so that the individual fibers can move more freely. This makes the material softer and more supple. Typical weight ratios of non-synthetic fiber material:softener are in the range of 1:0.01 to 1:0.4, or 1:0.05 to 1:0.35, or 1:0.1 to 1:0.3.
Fillers can be used if the non-synthetic sheet material according to the invention is to form a smooth surface and/or is to have a higher suppleness. Fillers can be selected from silicates, such as kaolin; carbonates, such as chalk or gypsum; metal oxides, such as titanium oxide or aluminium oxide; barium sulphate; nanocellulose, such as CNC (cellulose nanocrystals), CNF (cellulose nanofibrils), FNC (fibrillated nanocellulose); or mixtures thereof. Typical weight ratios of non-synthetic fiber material:filler are in the range of 1:0.1 to 1:1, or 1:0.15 to 1:0.9, or 1:0.2 to 1:0.8.
Dyes can be used if the non-synthetic textile surface structure is to have a specific colour. The non-synthetic textile surface structure can therefore be dyed, whereby the dyeing process can be carried out at different times during the process. For example, the dyeing can be carried out before, during or after step a). Either the non-synthetic fiber material or the pulp can be dyed. The dyes can be selected from inorganic pigments such as carbon, metal oxides or metal sulphates; natural dyes such as saffron, indigo, onion peel, quebracho wood extract, madder root extract, woad extract, brazilin, blue wood extract, synthetic dyes, such as direct dyes, cationic dyes, vat dyes, reactive dyes, developing dyes, food dyes, or mixtures thereof. The material to be coloured can be placed in a corresponding liquid/suspension. In addition, the finished non-synthetic textile surface structure can be dyed by applying dyes to the surface. Alternatively, dyes/pigments can be added to the pulp. By processing dyed fibers, the material is dyed thoroughly. This prevents colour abrasion—as is the case with a paint finish, for example.
In step a8), the pulp is produced, wherein the non-synthetic fiber material, the at least one binder, the at least one process additive and the at least one liquid are brought into contact with each other and mixed, so that the pulp is formed.
The sub-steps a1) to a8) of step a) of the method according to the invention can be carried out in any order, or even in parallel. For example, a portion of the non-synthetic fiber material may be subjected to step a2) while another portion of the non-synthetic fiber material is subjected to step a5). Preferably, step a6) is performed or carried out as the last sub-step in step a).
Furthermore, the method according to the invention comprises step b), wherein step b) may comprise one or more of the following substeps:
In step b1), the pulp provided in step a) is applied to a liquid-permeable carrier element, in particular a water-permeable carrier element for at least partial separation of the at least one liquid, in particular the water. The application can be carried out by suitable methods known from the prior art, such as brushing or pouring. The “liquid-permeable carrier element” is a device such as a sieve or a perforated plate onto which the pulp is applied to separate the liquid.
In step b2), a pulp layer is produced, comprising the pulp from step a), wherein the at least one liquid, in particular the water, is at least partially removed from the pulp layer. The at least one liquid is removed either by the action of gravity or by the action of an external force such as a pressure plate or the application of a vacuum. Once the liquid has been removed, the partially dried or partially dehydrated pulp layer is removed from the liquid-permeable carrier element. This distinguishes the liquid-permeable carrier element from carrier materials known from the prior art, which remain in the finished product.
In step b3), the pulp layer which was produced, for example, in step b2) is further dried until at least 90%, or at least 95%, or at least 98%, or at least 99% of the at least one liquid has been removed from the pulp layer. The drying can take place either at room temperature by evaporation or in suitable devices such as drying ovens at elevated temperatures and/or pressure. In step b3) the so-called sheet formation takes place. This sheet formation can be continuous or discontinuous. Continuous sheet formation requires large screening machines with vacuum suction (similar to a paper machine). Discontinuous sheet formation can be carried out using laboratory equipment (e.g. Rapid-Köthen sheet formers) or by hand, similar to paper scooping.
In step b4), a moulding process is carried out on the pulp layer, in particular on the dried pulp layer, to obtain the non-synthetic textile surface structure. Steps b3) and b4) can be carried out simultaneously, i.e., drying takes place at the same time as the moulding process. However, steps b3) and b4) can also take place one after the other, i.e., step b4) after b3) or vice versa. The moulding process can also be carried out using devices known from the prior art, such as rollers. The moulding performed in step b4) may include pressing and/or embossing the material. By pressing the material in the dried state, the surface becomes smooth, in some cases also slightly glossy by satinising.
In step b5), at least one auxiliary agent can be added, as already described above in step a7). Step b5) can be carried out at any time before or after or at the same time as steps b1) to b4).
The above-described substeps b1) to b5) of step b) of the method according to the invention can be carried out in any order or in parallel.
The method according to the invention may further comprise a step c):
The post-treatment may consist of one or more treatments selected from: fulling, cleating and/or milling; equipping with UV protection and/or flame retardancy and/or antimicrobial protection (e.g. by applying nano-silver), hydrophobisation (e.g. by applying a polymer emulsion); applying wet strength agents and/or sizing agents; embroidering; (laser) engraving; embossing (e.g. by means of plates or rollers); coating (e.g. with proteins or waxes); surface dyeing; pigment application (e.g. effect pigments). The aim of the post-treatment is to refine the non-synthetic textile surface structure or to provide it with certain properties. According to the invention, such post-treatments include coating or impregnating the non-synthetic textile surface structure, for example hydrophobising the surface with waxes. The surface can also be laser engraved or embroidered using a suitable device. The material can be embossed to give it a special look and feel, for example grain embossing to create an animal leather look. Logos, lettering etc. can also be embossed. As already described, further mechanical processing can also be carried out, for example by fulling, cleating and/or milling. This loosens the fibers, causing the material to lose stability and thus become softer or more supple.
One embodiment of the method according to the invention for producing a non-synthetic textile surface structure comprises the following steps:
The process according to the invention has the advantage that it can be based entirely on plant and/or plant-based raw materials, so that it can be carried out vegan on the one hand and petroleum-free on the other hand and can lead to a vegan, petroleum-free product, the non-synthetic textile surface structure according to the invention.
The terms “plant-based” or “natural” are used synonymously in the present application and mean that no synthetic, petroleum-based raw materials/substances are contained, or, for example, that the plant-based binder is derived from plant components, without the addition of artificial raw materials.
The process according to the invention can preferably be completely ecological, since the generated non-synthetic textile surface structure does not emit any microplastic abrasion, as is the case with synthetic fibers or artificial leather. By using natural fibers and plant-based raw materials, the product of the process according to the invention can be biodegradable.
Furthermore, the present problem is solved by a non-synthetic textile surface structure. In particular, the non-synthetic textile surface structure is obtainable by the method according to the invention described above. Preferably, the non-synthetic textile surface structure has a single-layer structure and consists entirely of plant-based materials. The non-synthetic textile surface structure according to the invention does not contain any leather of animal origin. Preferably, the non-synthetic textile surface structure according to the invention is free of petroleum-based components. Preferably, the non-synthetic textile surface structure according to the invention is free from chemicals that are hazardous to human health.
For the purposes of the present application, the term “non-synthetic textile surface structure” refers to a material which is similar to real or artificial leather, can be processed like leather and can therefore be used as a substitute for leather. The non-synthetic textile surface structure is non-woven. The non-synthetic textile surface structure within the meaning of the present application comprises at least one non-synthetic fiber material, at least one process additive and at least one binder, wherein the at least one binder comprises natural latex.
Furthermore, the non-synthetic textile surface structure according to the invention may comprise at least one auxiliary agent selected from plasticizers, dyes, UV protection agents, hydrophobicizing agents, antimicrobial agents, flame retardants, wet strength agents, sizing agents, pigments, or mixtures thereof. Examples and specific embodiments of these auxiliaries have already been described above in connection with the method according to the invention.
The plant-based textile surface structure basically has the same advantages as those mentioned above for the method according to the invention. The non-synthetic textile surface structure according to the invention can be produced entirely from plant and/or plant-based raw materials, so that it is vegan on the one hand and petroleum-free on the other. Due to the process according to the invention and the raw materials or auxiliaries used, it cannot contain any metal residues. The non-synthetic textile surface structure according to the invention does not produce any microplastic abrasion and is also biodegradable.
In contrast to animal skins, the thickness of the non-synthetic textile surface structure according to the invention is not predetermined by nature, but can be freely selected and controlled. The non-synthetic textile surface structure according to the invention can have a thickness that is customary for leather, and can have, for example, a thickness of between 0.2 and 5 mm.
The non-synthetic textile surface structure according to the invention can—unlike multi-layer artificial leather—be processed with open edges.
The non-synthetic textile surface structure according to the invention is a single-layer product that can be further processed using conventional methods. For example, it can be sewn, glued, nailed and embroidered.
Further according to the invention is the use of the non-synthetic textile surface structure according to the invention, in particular for the manufacture of textiles, seat covers, bags, applications. Possible areas of application are in fashion (shoe components, bags, accessories, clothing), furniture (seat covers, furniture surfaces), car interiors, stationery (e.g. covers). The non-synthetic textile surface structure according to the invention can also be used in the construction industry or in interior design, e.g., for façade paneling or floor coverings.
Also according to the invention is a leather substitute comprising the non-synthetic textile surface structure according to the invention. The leather substitute according to the invention can comprise decorations, engravings, embossings, embroideries, coatings, adhesions or mixtures thereof. The leather substitute according to the invention can be combined with other materials that can usually be combined with leather. The leather substitute according to the invention can be processed and used like conventional leather of animal origin or artificial leather. In particular, the leather substitute according to the invention, as well as the non-synthetic textile surface structure according to the invention, can have the same, similar or even improved properties compared to conventional leather of animal origin or artificial leather. Such properties include tensile strengths, for example in the range from 15 to 50 N/mm2, elongation at break, for example in the range from 10 to 50%, tear resistance, for example in the range from 4 to 40 N/mm, residual moisture, for example in the range from 0.5 to 10%, or abrasion resistance, for example in the range of >20,000 cycles according to Martindale.
The leather substitute according to the invention differs from the non-synthetic textile surface structure according to the invention in that the leather substitute according to the invention has already been optimised for the subsequent application, for example by cutting or further (surface) treatments, in order to achieve certain properties. Examples of such (surface) treatments have already been described above.
Further objectives, features, advantages and possible applications are shown in the figures and in the following non-limiting examples of embodiments of the invention. All the features described and/or illustrated form the object of the invention, either individually or in any combination, even independently of their summary in the claims or their relationship to one another.
In one embodiment, the non-synthetic textile surface structure according to the invention is made from hemp fibers. The fibers are obtained from a farm in Germany. The fibers are available as wool, as shown photographically in
In order to be able to produce a tear-resistant and homogeneous surface structure from the fibers in accordance with the present invention, they must first be mechanically processed. The preparation can be carried out in various machines. The process can be carried out either with a cone refiner known from the paper industry or with a Hollander. Water can be added to the fibers prior to the process. During the so-called refining process, the fibers are shortened, separated and fibrillated in the refining units. The result is a homogeneous fiber suspension. The suspension can then be cleaned, rinsed or thickened again using a pressure screen.
In the next step, the pulp is produced. The preferably diluted (plant-based) binder and the (plant-based) process additive are added to the fiber suspension one after the other. Successful fixation is clearly visible to the eye. The fibers flocculate noticeably and settle at the bottom of the container after a resting period.
The so-called sheet is then formed. Leaf formation can take place in both a continuous and a discontinuous process. Continuous sheet formation requires large screening machines with vacuum suction (similar to a paper machine). Discontinuous sheet formation can be carried out using laboratory equipment (e.g. Rapid-Köthen sheet formers) or by hand, similar to paper scooping.
During sheet formation, the water is separated from the other solids in the pulp. The pulp is placed on a sieve (water-permeable carrier element) for this purpose. Such a pulp layer is shown photographically in
The partially dewatered pulp layer in the form of a fiber mat is then transferred from the screen to a felt by inverting the screen box (only temporarily). For further dewatering, the fiber mat is pressed between two nonwovens in a press. The remaining liquid must be pressed out as slowly as possible to not damage the three-dimensional structure. After pressing, the formed sheet is already so tear-resistant that it is easy to handle. The sheet must now be dried further with room air until equilibrium is reached. Drying takes place in an oven at moderate temperatures or in the air.
In a continuous process, pressing and drying takes place via pairs of rollers and drying cylinders or via calenders.
The surface of the dried material can be further refined by embossing or pressing between metal plates or rollers.
In this way, the non-synthetic textile surface structure according to the invention is obtained. A specific embodiment of this non-synthetic textile surface structure is shown photographically in
The present invention is explained again below with reference to the examples, but without being limited to these.
200 g fibers (hemp, long wool fiber) are added to 18 liters of water in a Hollander. The subsequent grinding process is carried out for 30 minutes under standard weight. 10 g carbon black (as color pigment) and 60 g latex (binding agent) are added while stirring. 30 g of cationic starch (process additive) are dissolved in 3 liters of water, which is then also added. The pulp is stirred and the pulp precipitates while stirring. This pulp is then placed in a sieve box for dewatering. After dewatering, the generated partially dewatered pulp layer is placed between two layers of felt, pressed, and then air-dried.
A grey/black surface structure, haptically reminiscent of leather, is obtained. The surface structure is stiff after drying.
30 g of hemp fibers are cut to a length of 0.5 cm and mixed with water to a total weight of 300 g. The mixture is placed in a PFI mill and ground at normal weight for 3 minutes. The fiber suspension is then mixed with 1.5 liters of water and whipped in a whipping device. The pulp is then produced by adding 1 g of sulphated sunflower oil (plasticizer), 10 g of latex (binder), 2 g of kaolin (filler) and 1 liter of water. 0.01 to 0.02 M aluminum sulphate (process additive) is added under stirring until a pH value of 5 is reached, to precipitate or fix the pulp. The pulp obtained in this way is placed in a sieve box for dewatering. After dewatering, the generated, partially dewatered pulp layer is placed between two layers of felt, pressed, and then air-dried.
The non-synthetic textile surface structure shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2021 119 667.1 | Jul 2021 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/071283 | 7/28/2022 | WO |
