Patent Application
20230053954
The present invention relates to a method of manufacturing non-woven textiles from cellulose-rich waste, such as fruit and vegetable pomace. The present invention also describes a method of coating the non-woven textile to provide it with a hydrophobic surface. The present invention relates to food waste upcycling by converting fruit and vegetable waste obtained as by-product in industrial production into high-value textiles. In this sense, the present invention can provide as a substitute material for conventional animal leather.
With the emerging climate changes and a growing world population, there is an urgent need for sustainable and environmentally friendly materials to meet consumer needs and growing demands. Areas experiencing increasing demands include the food industry and the textile industry. Furthermore, the industries must adapt to the increasing consumer awareness regarding sustainability and animal health.
The fashion and design industries represent areas invested in finding sustainable materials, which are environmentally friendly and vegan. Conventional textile and leather production utilize hazardous ingredients and employ inadequate waste management practices. The environmental impact of the production processes, renewability of resources, and damage inflicted on ecosystems warrant health and sustainability concerns of consumers.
Enormous amounts of fruit and vegetable produce is wasted every year. In specific relation to industrial processing, approximately 1% to 20% of the pomace remaining after processing is wasted. Furthermore, >50% of the fruit and vegetable produce is wasted at different stages of the production. The wasted apple pomace is either landfilled, used as an animal feed, or used for production of low value products.
The use of fruit and vegetable waste for upscaling has been described previously. This includes the method disclosed in CN106748544, which relates to the production of fermented organic fertilizer from rural wastes, such as apple pulp and animal faeces. Additionally, US20050147723A1 discloses a method for making a nutrient-rich supplement powder based on apple peel subjected to phytochemical preservation treatment.
The use of fruit and vegetable pomace must not be limited to low value applications. Instead, upcycling fruit and vegetable waste to textile represents an opportunity of adding substantial value to the otherwise wasted fruit and vegetable pomace. Additionally, the pomace-derived textile serves as a sustainable and environmentally friendly alternative to the conventional animal textiles, such as for example animal leather.
The fruit and vegetable pomace-based non-woven textile is environmentally favourable as it employs a sustainable manufacturing process using environmentally friendly ingredients. At the same time, to meet the needs and expectations of consumers, the non-woven textile should retain features comparable to those of conventional textiles. An alternative textile to the conventional animal leather should include comparable characteristics in terms of water resistance, tensile strength, and physical appeal.
US2009301347A1 discloses an apple textile composition made up of apple flour and 5% polymer binder. However, the manufacturing technique for obtaining the apple textile can only be used for dry powders.
US20130149512A1 discloses a natural non-woven material made from a multi-layered stack of discrete interconnected plant fibre layers bound by a biodegradable polymer. The application relates to the use of plant-based fibres, in particular pineapple fibres, to manufacture a fused non-woven material.
WO2015018711A1 discloses a method for making spinnable cellulose from citrus fruits discarded by citrus fruit plantations or wasted during industrial processing of citrus fruit derivatives. The application discloses a method for chemical treatment used to extract cellulose from the citrus fruits. The method disclosed is, however, limited to citrus fruits and involves polysaccharide separation processes.
Furthermore it has been described of how to manufacture edible rolled sheets of fruit material from fruit mass, as exemplified by the methods disclosed in US20090169694A1 and KR100275214B1.
The company “Fruitleather Rotterdam”, featured in articles on the websites https://www.livingcircular.veolia.com/en/inspirations/rotterdam-unsold-fruit-becomes-fake-leather, https://en.reset.org/blog/voila-and-fruit-becomes-bag-09292015 and haps://mashable.com/2015/08/11/food-waste-fruitleather/?europe=true, turns fruit wastes, such as mangos, into fruit leather material. The websites, however, fail to disclose the manufacturing process used to obtain the fruit leather sheets.
Due to the challenges and disadvantages presented in the prior art, there is a need for an alternative production process to obtain a plant-based leather material with an improved tensile strength, appearance, and further advantageous material characteristics for its use as a textile material.
In view of the above, an object of the present invention is to provide a non-woven textile from fruit and/or vegetable waste. The resulting textile having physical properties comparable to those of conventional textiles, such as animal leather, concerning, for example, physical appeal, water resistance, and tensile strength of the textile. The present disclosure seeks to address the problems of negative environmental impact of industrial production, damages to ecosystem integrity, and poor waste utilization, posed by conventional textile production and food processing.
According to a first aspect of the inventive concept, it is provided a method for producing a hydrophobic non-woven textile, the method comprising the steps of providing fruit or vegetable pomace comprising water in the range of 60% to 95% (w/w) and a plant fibre, comminuting, preferably by milling or refining, the pomace to provide a disrupted pomace having fibres of a fibre length of below or equal to 2.0 mm, such as in the range of from 0.3 mm to 2.0 mm, 0.3 mm to 1.5 mm, 0.3 mm to 1.0 mm, 0.5 mm to 1.5 mm, 0.5 mm to 1.0 mm or 0.3 mm to 0.8 mm, mixing the disrupted pomace with a first, e.g. one or more, density-modifying agents at an amount of density-modifying agent in the range of 10% (w/w) to 85% (w/w), e.g. in the range of 10% to 40% (w/w), of the weight of the dry matter of the disrupted pomace, dehydrating, using one or more method from the list comprising heating, centrifugation, filtration, or mechanical pressing, the disrupted pomace by reducing the water content by 10% (w/w) to 30% (w/w), preferably by 10% (w/w) to 20% (w/w), to provide a water reduced pomace, optionally adding a second density-modifying agent at an amount of density-modifying agent in the range of 15% (w/w) to 60% (w/w) of the weight of dry matter of the disrupted pomace, distributing the water reduced pomace on a surface and drying the distributed water reduced pomace at a drying temperature in the range of 20° C. to 150° C., preferably in the range of 60° C. to 130° C., more preferably in the range of 70° C. to 110° C., e.g. in the range of 20° C. to 90° C., preferably in the range of 40° C. to 80° C., more preferably in the range of 45° C. to 70° C., for a drying duration to reduce the water content to 10% (w/w) to 30% (w/w) of the water reduced pomace, preferably to 20% (w/w) to 30% (w/w), to provide a non-woven textile, and coating the non-woven textile with a hydrophobic polymer to provide the hydrophobic non-woven textile.
The non-woven textile is manufactured using an environmentally favourable production process. The present invention can be produced in two forms: a sheet form, which is strong, flexible, stitchable, and durable, and in a vacuum-moulded 3D-form, which is strong, durable, and non-bendable. The sheet form can be used in applications in which conventional animal leather is used, including, but not limited to, clothing, accessories, book bindings, sports equipment, footwear, bags, furnishings, interior decors, automobile furnishing, etc. The vacuum-moulded 3D-form can be shaped into products with likeness to paper industry products, including, but not limited to, plates, bowls, packaging, wall panels, toys, etc.
By comminuting the pomace and by adding a density-modifying agent to the disrupted pomace according to the invention, it has surprisingly been found that the resulting textile material has an increased tensile strength, resulting in a versatile use of the textile material for several purposes. Particularly the addition of lignocellulosic fibres as density-modifying agents has been proven to increase the tensile strength of the non-woven textile (Example 4, Table 7). Also, the addition of natural rubber milk has been found to increase durability of the textile. Surprisingly, the method of the invention furthermore provides a non-woven textile with improved tactile and optical characteristics as well as improved material flexibility. The process disclosed herein minimizes the economical strain associated with drying the fruit and vegetable waste, embraces the natural composition of the waste, and delivers a product that satisfies perceptive and tactility requirements of the consumer.
The disclosed process is particularly advantageous due to its robustness in incorporating pomace of different compositions and varieties, such as pomace derived from apple, pear, citrus fruits, ginger, rhubarb, cactus, mango, pineapple, carrot, cucumber, tomato and the like. Fruit pomace generally includes a mixture of outer skin, fruit pulp, stems, and seeds, while vegetable pomace includes, outer skin, vegetable pulp, stalks, and roots. In a preferred embodiment, the pomace employed in the disclosed process is apple pomace obtained from industrial juice and cider production.
The disclosed process employs comminuting fruit and vegetable pomace, preferably by milling or refining, as the first step in the manufacturing process. The step of comminution is of particular relevance for the particle size and viscosity of the comminuted pomace and influence the texture of the final textile. Furthermore, water is optionally added during comminution of the pomace.
In one embodiment, the pomace is comminuted by milling, in which a toothed or stone colloidal mill is used, to reduce the particle size in the pomace from between 0.5 mm to 20 mm to a particle size of <0.1 mm. In another embodiment, the milling step increases the water content of the pomace by 20% to 80%, thus reducing the density by 20% to 80%.
In one embodiment, the mixing of the disrupted pomace with one or more density-modifying agents is at an amount of density-modifying agent in the range of 10% (w/w) to 40% (w/w) of the weight of the dry matter of the disrupted pomace.
In a preferred embodiment of the method of producing a hydrophobic non-woven textile, the density-modifying agent is selected from the list comprising carbohydrates, plant fibres, proteins, polymer emulsions, gums, polyols, cationic polymers, siloxanes and fatty acids. In one embodiment of the method of producing a hydrophobic non-woven textile, the density-modifying agent is selected from the list comprising carbohydrates, plant fibres, proteins, polymer emulsions, gums, polyols, and cationic polymers. In one embodiment of the method of producing a hydrophobic non-woven textile, the density-modifying agent is selected from the list comprising siloxanes and fatty acids. Surprisingly the inventors have found that the type and concentration of the density-modifying agent can be used to modify the flexibility and the tensile strength of the non-woven textile.
Non-limiting examples for suitable carbohydrates as density-modifying agents are starch, cellulose, microcrystalline cellulose, carrageenan, agar, sugar, and agaropectin.
Non-limiting examples for suitable plant fibres as density-modifying agents are softwood pulp, paper pulp, hemp, jute, flax, cotton, nettle, ramie, corn, bamboo, and straw.
Non-limiting examples for suitable polymer emulsions as density-modifying agents are latex milk, natural latex milk, rubber milk, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene copolymer, styrene-acrylic polymer emulsion, polyurethane, polylactic acid, acrylic, styrene, polyester, polyvinyl butyral (PVB), polyolefin copolymer and ethylene vinyl acetate copolymer. The inventors have surprisingly found that the addition of natural rubbers to the pomace can increase the durability of the non-woven textile product.
Non-limiting examples for suitable gums as density-modifying agents are guar gum, gum Arabic, gum ghatti, karaya gum, tara gum, dammar gum, and gum tragacanth. The addition of gums was surprisingly found to increase flexibility of the non-woven textile product (example 4, Table 8).
Non-limiting examples for suitable polyols as density-modifying agents are glycerol (synonyms: glycerine, glycerin), glycol, pentaerythritol, and polyethylene glycol (PEG). Surprisingly, the addition of glycerol to the pomace has been found to increase the product flexibility (example 5) rendering a more versatile use of the non-woven textile by preventing a break, rupture or fraction of the textile during bending of the textile.
A non-limiting example for a suitable cationic polymer as density-modifying agent is polyacrylamide.
Non-limiting examples for suitable siloxanes as density-modifying agents are silicone glycols, silicone emulsion, cyclosiloxane, organosiloxane, carboxysiloxane, amino siloxane, polysiloxane, polysiloxane adduct, silicone elastomer, silicone gum, silicone rubber and epoxy modified siloxane.
Non-limiting examples for suitable fatty acids as density-modifying agents are palmitic acid, linolenic acid, tall oil fatty acid, fatty acid esters, stearic acid and oleic acid.
When proteins are used as density-modifying agents, the proteins are preferably obtained from a plant source. The plant source can be by-products from industrial processes. Non-limiting examples for proteins are soy protein, whey protein, chia protein, flax protein, black bean protein, and mycoprotein. The protein can constitute up to 30% (w/w) of the final composition of the textile. The use of proteins has been found to be a suitable and efficient substrate for cross-linking reactions.
The density-modifying agent can act as a filler and has been found to enhance strength to the textile, to provide substrate for cross-linking reactions, or to aid in preserving moisture content in the textile. In particular, natural latex milk has surprisingly been found to enhance the textile durability of the material significantly. Alternatively or additionally the density-modifying agent itself can act as a cross-linking agent.
One embodiment describes a non-woven textile fortified with at least one density-modifying agent. Another embodiment describes a non-woven textile fortified with at least two, e.g. two different, density-modifying agent. The density-modifying agent is included in the textile in concentrations between 10% (w/w) to 85% (w/w) of the dry weight of disrupted pomace. In the process disclosed in the present invention, water is added together with the density-modifying agent to the disrupted pomace.
In another embodiment, a non-water-soluble complex carbohydrate or lignocellulosic fibre is preferred as density-modifying agent. The non-water-soluble complex carbohydrate or lignocellulosic fibre comprises carbohydrates, such as starch, cellulose, microcrystalline cellulose, carrageenan, agar, and agaropectin; plant fibres, such as softwood pulp, paper pulp, hemp, jute, flax, cotton, nettle, ramie, corn, bamboo, and straw; proteins; polymer emulsions, such as latex milk, natural latex milk, rubber milk, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene copolymer, styrene-acrylic polymer emulsion and ethylene vinyl acetate copolymer; gums, such as guar gum, gum Arabic, gum ghatti, karaya gum, tara gum, dammar gum, and gum tragacanth; and cationic polymers, such as polyacrylamide. The insoluble complex carbohydrate or lignocellulosic fibre preferably constitutes 5% (w/w) to 50% (w/w) of the final composition of the textile.
In addition to insoluble carbohydrates, the textile can contain water-soluble carbohydrates. Non-limiting examples for water-soluble carbohydrates are sugars such as maltodextrin, glucose, sucrose, maltose, trehalose or combinations thereof; and polyols, such as pentaerythritol, glycerol, glycol and polyethylene glycol (PEG). The soluble carbohydrate can constitute up to 20% (w/w) of the final composition of the textile.
In another embodiment, a step of odour and colour harmonization is included in the manufacturing process after the step of comminution of the pomace. In the fashion and design industries, it is important for a consumer product to have an appealing colour and smell. The optional step of odour and colour harmonization can, therefore, aid in obtaining a sensorial appealing textile.
Another embodiment employs sustainable bleaching using chlorine-free bleaching agents for odour and colour harmonization of the textile. Non-limiting examples for chlorine-free bleaching agents are hydrogen peroxide, sodium percarbonate, sodium perborate, benzoyl peroxide, potassium persulfate, sodium bicarbonate, sodium dithionite, sulfur dioxide, peracetic acid or ozone. Bleaching is carried out in a closed vessel with 0.005% (v/v) to 50% (v/v) at 30° C. to 90° C. and pH 2 to 13, preferably pH 10, for 1 hours to 48 hours with continuous stirring. The described embodiment is advantageous since it does not employ chlorine-containing agents. Toxic organochlorine is formed when chlorine radicals are reacted with cellulosic material. This embodiment thereby limits the amount of toxic waste produced.
Another embodiment describes the use of acidified solvents as an alternative to bleaching for odour neutralization and colour removal in the non-woven textile. Solvents can reduce the intensity of odour by solubilizing the molecules responsible for the odour. The solvents used for treatment of the pomace can be isolated from the solvent-pomace slurry by, for example, different methods of distillation, including, but not limited to simple distillation, fractional distillation, steam distillation, vacuum distillation, and short path distillation. The distillation allows for the solvents to be reused. In the present embodiment, the solvents are economical and do not leave any residual odour or fragrance in the slurry. Environmentally-friendly non-toxic solvents may include, but are not limited to, ethanol, butane, acetone, chlorine, 3-methoxy-3-methyl-1-butanol, ethylene glycol monobutyl ether, and supercritical carbon-dioxide, for example. The solvents are acidified with weak organic acids, which may include, but are not limited to citric acid, acetic acid, formic acid, benzoic acid, phosphoric acid, oxalic acid, and lactic acid, for example. The acidified solvent treatment is carried out in a closed vessel at between 25° C. to 30° C. and between pH 1 to 3, preferably pH 2, for 4 hours to 120 hours with continuous stirring.
In another embodiment, cross-linking agents capable of cross-linking molecules of carbohydrates or molecules of proteins may be added during the manufacturing of the non-woven textile. Furthermore, the cross-linking agent may be activated by a catalyst. The addition of cross-linking agents in the manufacturing of the non-woven textile can help to increase the strength of the textile. The cross-linking agent is selected from the list comprising bifunctional cross-linking agents, dialdehydes, acetals, polycarboxylic acids, phosphorus derivates, protein cross-linking agents, homo-bifunctional cross-linking agents, hetero-bifunctional cross-linking agents, enzymatic cross-linking agents, or combinations thereof.
In one embodiment, the cross-linking agent is chosen for carbohydrates. Non-limiting examples for cross-linking agents are dialdehydes (such as glyoxal and glutaraldehyde), acetals (such as 1,1,4,4-tetramethoxybutane and 1,1,5,5-tetramethoxybutane), polycarboxylic acids (such as acrylic, maleic, polymaleic, succinic polyitaconic, and citric acids), phosphorus derivatives (such as phosphoric acitriethyld and phosphate), silica derivatives (such as tetraethoxysilane), epichlorohydrin, polyepichlorohydrin, polyamidoamine epichlorohydrin (PAE), polyacrylamide, and glyloxilated polyacrylamide. The carbohydrate cross-linking agent may constitute 0.5% (w/w) to 10% (w/w) of the final composition of the textile. In one particular embodiment, the addition of PAE cross-linking agent together with soft wood fibres and sucrose surprisingly resulted in a non-woven textile with tensile strength of >10 N/mm2 (Example 4, Table 10).
In another embodiment, the cross-linking agent chosen for proteins may be a chemical or enzymatic cross-linking agent. Protein cross-linking agents are molecules that contain two or more reactive ends capable of chemically attaching to specific functional groups on proteins. Attachment between two groups on a single protein results in intramolecular cross-links, which stabilize the tertiary or quaternary structure of the protein. Attachment between groups of two different proteins results in intermolecular cross-links. The intermolecular cross-links stabilize protein-protein interaction. Non-limiting examples for chemical cross-linking agents for proteins are homo-bifunctional agents, such as, glutaraldehyde, dithiobis (sulfosuccinimidylpropionate), dimethyl adipimidate (DMA), dimethyl suberimidate (DMS), and dimethyl pimelimidate (DMP), as well as hetero-bifunctional agents, such as, maleimides, pyridyl disulfides, bis[2-(4-azidosalicylamido)ethyl)] disulfide, succinimidyl 3-(2-pyridyldithio)propionate, and succinimidyl trans-4-(maleimidylmethyl)cyclohexane-1-carboxylate. Non-limiting examples for enzymatic cross-linking agents are transglutaminases, sortases, lysyl oxidases, and oxidoreductases. In a preferred embodiment the protein cross-linking agent constitutes 0.1% (w/w) to 10% (w/w) of the final composition of the textile.
Non-limiting examples for catalysts for cross-linking agents are titanium dioxide, sodium dihydrogen phosphate, polyethylene glycol. Catalysts may constitute 0.2% (w/w) to 1% (w/w) of the final composition of the textile. A surprising effect of the catalyst titanium dioxide in use together with the cross-linking agent citric acid on the tensile strength has been observed in one embodiment, namely in example 4 (Table 10).
In one embodiment, the method for dehydrating the pomace to yield a water reduced pomace is selected from the list comprising heating, centrifugation, vacuum filtration, belt filtration, hot filtration, cold filtration, cloth filtration, mechanical press, hydraulic press or forging press.
In a preferred embodiment, the dehydrating step to reduce the water content of the disrupted pomace is achieved using the method of heating. For the heating, the temperature is in the range of 50° C. to 80° C., and the pomace is maintained at the temperature for a given duration to reduce the water content in the pomace by 10% (w/w) to 30% (w/w), preferably by 10% (w/w) to 20% (w/w).
When dehydration of the disrupted pomace involves heating, the density-modifying agents and optionally the cross-linking agents may be added after the heating step in the manufacturing process. If, for example, the density-modifying agent or cross-linking agent has a low decomposition temperature, is volatile, is an enzyme, coagulates, or is toxic when heated, the agent is added after the heating step. Heating the pomace allows homogeneous distribution and promotes carbohydrate/protein intra- or intermolecular interactions. Exemplary, the heating is carried out at 50° C. to 80° C. to reduce the water content of the pomace by 20% to 25%. Additionally or alternatively, the pomace mixture is continuously stirred during the heating to further improve the homogeneous distribution.
In one embodiment, the second density-modifying agent added after heating of the disrupted pomace is the polymer emulsions, such as latex milk, natural latex milk, rubber milk, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene copolymer, styrene-acrylic polymer emulsion and ethylene vinyl acetate copolymer, and gums such as guar gum, gum Arabic, gum ghatti, karaya gum, tara gum, dammar gum, and gum tragacanth. The inventors found that adding the natural rubbers or gums after heating helped to preserve the integrity of the agents.
In another embodiment, a colorant and/or an antimicrobial agent is added to the pomace mixture after the dehydration step and before the forming and drying steps in the manufacturing process. Non-limiting examples for the inorganic colorants are metal oxide, such as titanium dioxide, iron oxide, and ultramarine blue, earth pigments, such as natural mineral powders and mica powders. Non-limiting examples for the organic colorant are Indigofera tinctora, Haematoxylum campechianum, Rubia tinctorum, Madura pomifera, Punica granatum, Schinopsis lorentzii, and Reseda luteola, phthalocyanine, diketopyrrolo-pyrrole, and quinacridone. The colorant may constitute 0.1% (w/w) to 50% (w/w) of the final composition of the textile. In one embodiment iron oxide colorant is used at a concentration of 0.5% (w/w) with no binder to obtain a vibrant black-coloured sample. In the context of the present invention, the term “colorant” describes a substance, whether it being a pigment powder, pigment preparation or dye, that can inherently give the non-woven textile the wanted colour, shade or nuance. In the context of the present invention, the terms colorant and dye are used interchangeably.
Colorants can be used in combination with binders. Non-limiting examples for binders are acetic acid, citric acid, alum, potassium bitartrate, ferrous sulphate, copper sulphate, and sodium carbonate, polyurethane, acrylic, styrene, polyester, polyvinyl butyral, polyolefin copolymer and vinyl chloride-vinyl acetate copolymer (VC/VAC copolymer). The binder may constitute 0.1% (w/w) to 10% (w/w) of the final composition of the textile. Non-limiting examples for antimicrobial agents are green preservatives, such as carvacol and lecithin mixtures, oligochitosan hydrochloride from mushrooms, green/benzoates/sorbates from mushrooms, preservatives from Inula viscosa, tea tree oil, jojoba oil, and grapefruit extract, and antibiotic/antimicrobial agents non-toxic to humans. Non-limiting examples for antibiotic or antimicrobial agents which are non-toxic to humans are cephalosporins, penicillins, erythromycin, benzyl alcohol, dehydroacetic acid, salicylic acid, sorbic acid, and glycerin. The antimicrobial agent may constitute 0.05% (w/w) to 5% (w/w) of the final composition of the textile. If the colorant or the antimicrobial agent is hydrophobic, they can be applied to the textile as a coating together with a binder after the drying step in the manufacturing process.
The disclosed method for manufacturing a hydrophobic non-woven textile includes a forming and drying step. The water reduced pomace is distributed on a surface to have a thickness in the range of 0.2 mm to 20 mm, preferably in the range of from 1.0 mm to 10 mm, more preferably in the range of from 1.0 mm to 8 mm, and more preferably in the range of from 1.0 mm to 5 mm. In a preferred embodiment, the water reduced pomace is distributed on a surface to have a thickness in the range of 0.5 mm to 2.0 mm. Prior to drying, the water reduced pomace is distributed in frames. The forming frames are made up of materials, which may include, but are not limited to, glass, wood, stone, ceramic, unglazed ceramic, biodegradable polymer, and textiles. The size and type of frame can be changed to fit the required application. The frames aid in achieving a suitable shape, size, and texture of the non-woven textile. The drying of the material into different shapes and thicknesses allows a very versatile use of the finished product, e.g. thin material for accessories and thick material for packaging.
The water reduced pomace can also be distributed on a conveying belt. The conveying belt is made up of materials which may include, but are not limited to, urethane (polyurethane), polyolefin, silicone, PVC, mesh, nitrile, polyester, and polypropylene. The belt convey the water reduced pomace through a gap consisting of conveyer belt and rollers, or scraper, or blades to define the width and thickness of the non-woven textile.
The disclosed drying step allows for reducing the water activity and water content of the pomace. The reduced water activity and reduced water content of the pomace enable improved tensile strength, storage conditions, and avoid decay processes. The pomace may be dried by any method known to a person skilled in the art. Exemplary, the pomace can be dried by air-drying, freeze-drying, roller-drying, spray-drying, vacuum-drying, microwave-drying, or combinations thereof. The inventors have explored several drying techniques and were surprised to see that air-drying had several advantages over the other drying techniques. Drying is carried out at between 20° C. to 150° C., e.g. between 20° C. to 90° C. for 2 to 48 hours to reduce the water content of the pomace to 15% to 30%. It was observed that the moisture content for optimal flexibility and strength of the textile depends on the thickness of the samples, wherein thicker textile samples have higher moisture contents.
In one embodiment, the step of distributing the water reduced pomace on a surface and drying the distributed water reduced pomace is carried out at a drying temperature in the range of 20° C. to 90° C., preferably in the range of 40° C. to 80° C., more preferably in the range of 45° C. to 70° C., for a drying duration to reduce the water content to 10% (w/w) to 30% (w/w) of the water reduced pomace, preferably to 20% (w/w) to 30% (w/w), to provide a non-woven textile.
In one embodiment, the drying step comprises drying of the pomace as a vacuum-moulded 3D-form. Vacuum-moulding in a 3D-form allows the production of a non-woven textile which is strong, durable, and non-bendable. The vacuum-moulded 3D-form can be shaped into products with likeness to paper industry products, including, but not limited to, plates, bowls, packaging, wall panels, toys, etc.
In a preferred embodiment of the method of producing a hydrophobic non-woven textile, the coating comprises one or more of spray coating, wet spray coating, immersion dip coating, suspension plasma spraying, roller coating, direct coating, foamed foam coating, crushed foam coating, transfer coating, hotmelt extrusion coating, calendar coating, rotary screen coating, dry powder coating, curtain coating, slot-die coating, extrusion coating, mayer rod coating, kiss roll coating, gravure roll coating and reverse roll coating.
The non-woven textile is subjected to hydrophobic coating to achieve the hydrophobic non-woven textile. The disclosed coating technique and coating formulations achieve good results in terms of coating uniformity, smoothness, adhesion, and water repellent properties.
In one embodiment, the polymer solutions for coating are prepared at concentrations between 0.1 g per mL to 0.5 g per mL of solvent, together with conditioning agents at concentrations between 1 μL per ml to 10 μL per mL of solvent (if required), and held in stirred suspension at 25° C. In the case of spray coatings, a technique compatible with commercial wet-spray processes, which utilizes compressed air, has been developed in the disclosed method. For this technique, the polymer solutions are applied to the textile to form a coating film over the surface of the textile. The solvent is evaporated at 25° C. for 30 min before applying the next layer of coating. When using suspension plasma spraying for coating, the polymer is loaded into the feeder hopper and a combustion spray gun has been tested for trials.
In another preferred embodiment of the method of producing a hydrophobic non-woven textile, the coating step comprises applying one or more coating layers, wherein each coating layer comprises one or more of an amphiphilic polymer, a hydrophobic polymer and a conditioning agent. The application of several layers of coating is easily applicable during production and provides coating layers with several functions to increase the overall hydrophobic property of the textile.
A range of water resistant polymers may be used for coating the non-woven textile. This includes a multi-layered coating comprising at least one hydrophobic polymer, optionally a layer comprising a binder, such as an amphiphilic polymer, and optionally a layer comprising a conditioning agent. Non-limiting examples for hydrophobic polymers are polyvinyl butyrate, polydimethylsiloxane, sodium carbonate decahydrate, Colophonium, polylactic acid (PLA), poly-3-hydroxybutyrate and carboxylated styrene-butadiene emulsion. Non-limiting examples for amphiphilic polymers are polyacrylic acid, polyethyleneimine, polyvinylpyrrolidone, polyvinyl alcohol, polyvinyl acetate, carboxymethylcellulose, and hydroxyethyl cellulose. Non-limiting examples for conditioning agents are alkyl citrates, acetylated monoglycerides, epoxidized vegetable oils, methyl ricinoleate, dibutyl sebacate, dimethyl/dioctyl adipate, dibutyl/diisobutyl maleate, polyethylene glycol, polypropylene glycol, glycerol, potassium oleate, potassium cocoate, and potassium palm kernalate.
In another embodiment, the coating layer comprising a hydrophobic polymer may additionally include a plasticizer. Triethylene glycol bis(2-ehtylhexanoate) is a non-limiting example for a preferred plasticizer. The plasticizer can be added to the coating layer of the non-woven textile to alter the physical properties of the material by increasing the plasticity or decreasing the viscosity of the textile material.
In a preferred embodiment, a hydrophobic non-woven textile is obtained by the method of producing a hydrophobic non-woven textile according to above described embodiments. The disclosed method describes a process of upcycling fruit or vegetable pomace obtained as a by-product of industrial processes, such as those of juice and cider production, sugar extraction, and oil extraction, for example. According to the present inventive concept, approximately 2 kg to 10 kg of fruit or vegetable pomace allow for the manufacturing of 1 square meter of the hydrophobic non-woven textile with a thickness of around 0.5 mm to 1.5 mm.
According to a second aspect of the present inventive concept, a non-woven hydrophobic textile is provided, which comprises water, a fruit or vegetable material comprising a plant fibre, a density-modifying agent, and a layer of hydrophobic coating, wherein the content of water is in the range of from 10% (w/w) to 30% (w/w), e.g. in the range of from 15% (w/w) to 30% (w/w), of the hydrophobic non-woven textile, the content of the density-modifying agent is in the range of from 4% (w/w) to 70% (w/w), e.g. in the range of from 4% (w/w) to 40% (w/w), of the hydrophobic non-woven textile, and plant fibre having a fibre length of below or equal to 2.0 mm, such as in the range of from 0.3 mm to 2.0 mm, 0.3 mm to 1.5 mm, 0.3 mm to 1.0 mm, 0.5 mm to 1.5 mm, 0.5 mm to 1.0 mm or 0.3 mm to 0.8 mm. For example, according to a second aspect of the present inventive concept, a non-woven hydrophobic textile is provided, which comprises a layer of a non-woven textile and a layer of hydrophobic coating, wherein the non-woven textile comprises water at a content in the range of from 10% (w/w) to 30% (w/w) of the hydrophobic non-woven textile, a fruit or vegetable material comprising a plant fibre having a fibre length of below or equal to 2.0 mm, and one or more density-modifying agents at a content in the range of from 4% (w/w) to 70% (w/w) of the hydrophobic non-woven textile, and the hydrophobic coating comprises a hydrophobic polymer.
With regards to the described hydrophobic non-woven textile, it has surprisingly been found that the textile is water resistant, has a good tensile strength, and physical appeal. Furthermore, the disclosed non-woven textile is vegan and has a unique texture. Optionally, the pomace-based non-woven textile can be subjected to different colorants to achieve a coloured non-woven textile, to bleaching agents for odour and colour harmonization, and to multiple layers of coating for changing the physical properties of the non-woven textile.
In one embodiment, the hydrophobic non-woven textile of the present invention comprises one or more density-modifying agents at a content in the range of from 4% (w/w) to 40% (w/w) of the hydrophobic non-woven textile.
In one embodiment, the hydrophobic non-woven textile of the present invention has a thickness in the range of 0.2 mm to 20 mm, preferably in the range of from 1.0 mm to 10 mm, more preferably in the range of from 1.0 mm to 8 mm, more preferably in the range of from 1.0 mm to 5 mm. In a preferred embodiment, the hydrophobic non-woven textile of the present invention has a thickness in the range of 0.5 mm to 2.0 mm. Providing the material in several thicknesses enables various applications of the material in different products. Also, the flexibility of the textile is to a large portion defined by the thickness of the textile. Thereby various degrees of material flexibility can be designed through pre-determined textile thickness.
In the present invention, the tensile strength of the textile is an important measure in the evaluation of the performance and durability of the textile. The tensile strength is defined as a stress, which is measured as force per unit area. In the present invention, tensile strength is thus given in Newtons per squared millimetre (N/mm2). Furthermore, in the present invention the tensile strength is determined according to standard ISO 3376-2011. It has surprisingly been found that the fibre particle length influences the tensile strength of the textile. Thereby the tensile strength can be designed through different ways of comminuting, achieving different fibre particle length depending on the intended use of the hydrophobic non-woven textile. Surprisingly, also cross-linking reactions and the type and amount of density-modifying agent has been found to alter the tensile strength of the non-woven textile significantly.
In a preferred embodiment the hydrophobic non-woven textile has a tensile strength in the range of from 5 N per mm2 to 20 N per mm2, 5 N per mm2 to 12 N per mm2, 6 N per mm2 to 12 N per mm2, 6 N per mm2 to 10 N per mm2, 6 N per mm2 to 9 N per mm2 or 8 N per mm2 to 10 N per mm2. The tensile strength of the textile is important when evaluating flexibility, strength, and durability of the product. A good tensile strength results in a textile with features suitable for the production of clothing, accessories, book bindings, sports equipment, footwear, bags, furnishings, interior decors, toys, and automobile furnishing, for example.
In another embodiment, the non-woven textile comprises two different density-modifying agents. In one embodiment, the two different density-modifying agents are a first density-modifying agent at a content in the range of 4% (w/w) to 40% (w/w) of the hydrophobic non-woven textile and a second density-modifying, which is different from the first density-modifying agent, at a content in the range of 10% (w/w) to 66% (w/w) of the hydrophobic non-woven textile.
In another embodiment, the two different density-modifying agents are a first density-modifying agent at a content in the range of 4% (w/w) to 40% (w/w) of the hydrophobic non-woven textile and a second density-modifying, which is different from the first density-modifying agent, at a content in the range of 10% (w/w) to 40% (w/w) of the hydrophobic non-woven textile.
In one embodiment, the non-woven textile comprises two or more different density-modifying agents, such as three or four different density-modifying agents.
In a preferred embodiment, the hydrophobic non-woven textile comprises a density-modifying agent selected from the list consisting of carbohydrates, such as starch, cellulose, microcrystalline cellulose, carrageenan, agar, sugar, and agaropectin; plant fibres, such as softwood pulp, paper pulp, hemp, jute, flax, cotton, nettle, ramie, corn, bamboo, and straw; proteins; polymer emulsions, such as latex milk, natural latex milk, rubber milk, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene copolymer, styrene-acrylic polymer emulsion and ethylene vinyl acetate copolymer; gums, such as guar gum, gum Arabic, gum ghatti, karaya gum, tara gum, dammar gum, and gum tragacanth; polyols, such as glycerol, glycol, pentaerythritol and polyethylene glycol (PEG); cationic polymers, such as polyacrylamide; siloxanes, such as silicone glycols and polysiloxane adduct; and fatty acids, such as fatty acid esters. It has surprisingly been found that the addition of density-modifying agents is not only modifying the pomace density but can also modify the tensile strength, the flexibility and the appearance of the non-woven textile.
In a further embodiment, the hydrophobic non-woven textile comprises at least 30% (w/w) of fruit or vegetable material. Additionally or alternatively, the non-woven textile comprises at least 40% (w/w) fruit or vegetable material. Using a defined amount of fruit or vegetable material enables to control the overall amount of plant or vegetable fibres in the non-woven textile.
In one embodiment, fruit or vegetable material from more than one type of fruit or vegetable are used for the production of the hydrophobic non-woven textile. By using more than one type of fruit or vegetable useful characteristics of the fruit or vegetable compositions can be merged to produce non-woven textiles for various purposes.
In another embodiment, the hydrophobic coating of the hydrophobic non-woven textile further comprises one or more of an amphiphilic polymer and a conditioning agent. The listed polymers and agent can be coated as separated layers, such as one layer of the amphiphilic polymer, one layer of the hydrophobic polymer and one layer of the conditioning agent, or they can be coated as layers which partially mix with another. If the polymers are coated as layers, the number of layers can be one, such as a single hydrophobic layer, two, such as a layer of a hydrophobic polymer and a layer of conditioning agent or such as a layer of a hydrophobic polymer and a layer of an amphiphilic polymer, or three, such as a first layer of amphiphilic polymer, a second layer of hydrophobic polymer and a third layer of conditioning agent. The coating with different layers of polymers and/or agents provides a versatile platform to equip the textile with distinct hydrophobic properties for its use within e.g. clothing, accessories, sports equipment, footwear, bags, furnishings, and automobile furnishing, or other fields where hydrophobic properties are advantageous and/or desired by the customer.
According to a third aspect of the present inventive concept, a composite material is provided which comprises the hydrophobic non-woven textile according to the present inventive concept, an adhesive layer and a backing. The inventors have surprisingly found that the addition of a backing material to the hydrophobic non-woven textile of the present inventive concept enhances the overall performance of non-woven textile.
In a preferred embodiment, glue may be used as the adhesive layer between the non-woven textile and the backing. The glue is selected from the list of dextrin, latex, modified latex, polyvinyl acetate, polyurethane, polyacrylic, polychloroprene, epoxy, cyanoacrylate, aliphatic resin, bone glue, hide glue and hotmelt including ethylene-vinyl acetate, polyolefins, polyamides and styrene block copolymers. In one embodiment, the glue is an ester acrylic copolymer. The glue used greatly influenced the final appearance of the composite material as well as the durability of the composite material.
The backing applied to the non-woven textile of the present invention via the adhesive layer may be selected from list of a textile backing, a glass fiber, a carbon fiber, a metal mesh and a latex sheeting.
In one embodiment, the backing is a textile backing selected from the list consisting of non-woven textiles, woven textiles, polyester tulle textiles, cotton tulle textiles and knitted textiles. Non-limiting examples for woven textiles as textile backing are cotton plain woven textile, linen plain woven textil, pima cotton satin woven textile, cotton twill woven textile, polyester plain woven textile, chiffon, and regenerated cellulose twill woven textile. Non-limiting examples of weave patterns of the woven textile are plain weave, twill weave and satin weave. Non-limiting examples for knitted textiles as textile backing are cotton knitted textile, cotton wrap knitted textile, wrap knitted textile of cotton/polyester-blend, polyester knitted textile, polyester wrap knitted textile and polypropene wrap knitted textile.
The performance of the composite material of the present invention may be evaluated by its tear strength. The tear strength or tear resistance of the composite material is an important measure in the evaluation of how well a material can withstand the effects of tearing and thereby the durability of the composite material. The tear strength is defined as the maximum force required to tear a material in a direction normal to (perpendicular to) the direction of the stress. In the present invention, the tear strength is thus given in Newtons (N). It has surprisingly been found that the textile backing influences the tear strength of the composite material significantly. Thereby the tear strength can be altered through variation in the textile backing depending on the intended use of the hydrophobic non-woven textile. In an embodiment, the composite material has a tear strength in the range of 2 N to 45 N, such as in the range of from 5N to 40 N, 5N to 35 N, 7 N to 40 N, 10 N to 35 N or 15 N to 35 N as tested and evaluated according to the standard ISO 3377-1-2016.
In the above, the invention has mainly been described with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended claims.
Other objectives, features, and advantages of the present inventive concept will appear from the following detailed disclosure, from the attached claims, as well as from the drawings. Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to “a/an/the [textile, material, agent, polymer, step, etc.]” are to be interpreted openly as referring to at least one instance of said textile, material, agent, polymer, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.
In the context of the present invention, the term “hydrophobic” refers to the property of the non-woven textile to repel water at least on a portion of the surface of the non-woven textile. A hydrophobic textile exhibits hydrophobicity and therefore may be termed hydrophobic. The hydrophobic interaction is mostly an entropic effect originating from the disruption of the highly dynamic hydrogen bonds between molecules of liquid water by the nonpolar solute forming a clathrate-like structure around the non-polar molecules. Hydrophobicity is the physical property of a hydrophobic molecule or material that is seemingly repelled from a mass of water, or vice versa, a mass of water which is seemingly repelled from a hydrophobic molecule or material, such as from a hydrophobic non-woven textile. Hydrophobic molecules or materials tend to be nonpolar and, thus, prefer other neural molecules and solvents. Also, water on hydrophobic surfaces of hydrophobic materials or textiles will exhibit a low contact angle. Generally, if the water contact angle is smaller than 90°, the surface of the material or textile is considered hydrophobic, and if the water contact angle is larger than 90°, the surface of the material or textile is considered hydrophilic.
In the context of the present invention, the term “non-water-soluble” refers to compounds that are mostly polymers, and is defined as non-water-soluble if <10% (w/w) of the compound does not dissolve completely in water at room temperature within 1 hour.
In the context of the present invention, the term “w/w” refers to “weight for weight” or “weight by weight” and gives the proportion of a particular substance within a mixture, as measured by weight or mass.
In the context of the present invention, the term “v/v” refers to the volume concentration of a solution and is expressed as % v/v, which stands for volume per volume of liquids in a solution.
In the context of the present invention, the term “fruit or vegetable material” is the fruit and vegetable product comprising dry matter and water. The fruit or vegetable material may be obtained from fruit and/or vegetable processing, such as from industrial production of for example juice and/or cider.
In the context of the present invention, the term “one or more density-modifying agents” is to be understood as at least one density-modifying agents being added, the density-modifying agent being selected from the list of different density-modifying agents. When for example two, three or four density-modifying agents are used, then the two, three or four density-modifying agents are different density-modifying agents.
In the context of the present invention, the density modifying agent being added in the range of 10% (w/w) to 85% (w/w) of the weight of the dry matter of the disrupted pomace is to be understood as each individual density-modifying agent being added in the range of 10% (w/w) to 85% (w/w) of the weight of the dry matter of the disrupted pomace.
In the context of the present invention, the term “carrageenan” describes a family of linear sulphated polysaccharides that are extracted from red edible seaweeds, the term “agar” (or “agar-agar”) describes a jelly-like substance obtained from red algae. Agar is a mixture of two components: the linear polysaccharide agarose, and a heterogeneous mixture of smaller molecules called agaropectin.
In the context of the present invention, the term “hemp” describes a strain of the Cannabis sativa plant species that is grown specifically for the industrial uses of its derived products, such as fibre products. A synonym for hemp fibre is “bast”, which refers to the fibres which grow on the outside of the plant's stalk.
In the context of the present invention, the term “jute” describes a long, soft, shiny vegetable fibre which can be used for various textile application. Jute is produced primarily from plants in the genus Corchorus; the term “flax” describes a bast fibre which is extracted from the plant of the linseed/flax plant (Linum usitatissimum). In the context of the present invention, the term “cotton” describes a soft, staple fibre that grows around the seeds of the cotton plants of the genus Gossypium in the mallow family Malvaceae; the term “nettle” describes a very strong fibre derived from the plant Urtica dioica; the term “ramie” describes any of several fibre-yielding plants of the genus Boehmeria, belonging to the nettle family (Urticaceae) and their fibre, one of the bast fibre group; the term “corn” or “corn fibre” describes any fibre derived from the corn plant Zea mays; the term “bamboo” or “bamboo fibres” describes a cellulosic fibre that is regenerated from bamboo plant, typically bamboo used for fibre preparation is 3 to 4 years old; the term “straw” describes fibre from straw as an agricultural by-product consisting of the dry stalks of cereal plants after the grain and chaff have been removed.
In the context of the present invention, “hemp”, “jute”, “flax”, “cotton”, “nettle”, “ramie”, “corn”, “bamboo”, and “straw” can exist in different forms, such as a newly harvested, or raw form, and in refined, or spun form, which influence the performance of the fibres.
In the context of the present invention, the term “softwood pulp” describes a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibres from wood of softwood trees including spruce, pine, beech, aspen, fir, larch and hemlock, whereas the term “paper pulp” describes a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibres from paper or waste paper.
In the context of the present invention, the term “guar gum”, also called guaran, describes a galactomannan polysaccharide extracted from guar beans with thickening and stabilizing properties; the term “gum Arabic”, also known as gum sudani, acacia gum, Arabic gum, gum acacia, acacia, Senegal gum or India gum, describes a natural gum consisting of the hardened sap of various species of the acacia tree; the term “gum ghatti”, also known as Indian gum, describes a complex non-starch polysaccharide exuded from the bark of the tree Anogeissus latifolia of the family Combretaceae; the term “karaya gum”, also known as gum sterculia or Indian gum tragacanth, describes an acid polysaccharide produced as an exudate by trees of the genus Sterculia; the term “tara gum”, also known as Tara spinosa; describes a galactomannan polysaccharide extracted from the endosperm of Tara spinosa seeds; the term “dammar gum”, also known as Dammar or damar gum, describes a triterpenoid resin obtained from the tree family Dipterocarpaceae; the term “gum tragacanth”, also known as Shiraz gum, gum elect or gum dragon, describes a mixture of polysaccharides, which is obtained from dried sap of several species of Middle Eastern legumes of the genus Astragalus; the term “latex milk” or “latex” or “natural latex milk” describes a stable dispersion (emulsion) of polymer microparticles in an aqueous medium found in nature as a milky fluid in ca. 10% of all flowering plants and is a complex emulsion consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins and gums that coagulate on exposure to air; the term “rubber milk” describes latex from the rubber tree Hevea brasiliensis.
The above, as well as additional objects, features, and advantages of the present inventive concept will be better understood through the following illustrative and non-limiting detailed description of preferred embodiments of the present inventive concept, with reference to the appended drawings, wherein:
The present invention in a first aspect relates to a method for producing a hydrophobic non-woven textile from fruit or vegetable pomace. In a second aspect the invention relates to a hydrophobic non-woven textile comprising a fruit or vegetable material, a density-modifying agent, and a layer of hydrophobic coating. In a third aspect, the invention relates to a composite material comprising a hydrophobic non-woven textile comprising a fruit or vegetable material, a density-modifying agent and a layer of hydrophobic coating, an adhesive layer and a backing.
The following examples relate to 2D hydrophobic non-woven textile compositions made from fruit or vegetable pomace in which apple pomace serves as a representative example. The examples are included solely to assist one of ordinary skill in obtaining a more complete understanding of the present invention. The examples are not intended in any way to otherwise limit the scope of the present invention.
In some embodiments, apple pomace is used as the starting material for the non-woven textile. Apple pomace is obtained as a by-product of apple juice and/or cider production. 100% (w/w) of the apple pomace can be used for production of the non-woven textile of the present invention. However, besides apple pomace, also the pomace of other fruits or vegetables can be used as a starting material in the present invention. Tables 1-4 summarize the composition of regular biomass including apple pomace and banana peels. The percentages are given in % (w/w).
This example describes an odour and colour harmonization step as a part of the manufacturing process. Herein, bleaching with oxidizing agents is described as a suitable method of odour and colour harmonization of the apple pomace. Bleaching with hydrogen peroxide (H2O2) is carried out in a closed tank with 0.01% (w/w) to 0.04% (w/w) of 31% 14202 at 80° C. and pH 10 for 1h with continuous stirring. The pH of the solution is preferably adjusted with a base, sodium hydroxide (NaOH) for example, to the desired pH. Representative findings related to these experiments are depicted in Table 5.
The assessments of degree of offensiveness in regard to colour and odour were carried out by a panel of organoleptically-trained experts. The degree of offensiveness of the odour and colour are given in values between 0 and 10, in which 0=no odour, and 10=extremely odorous. Table 5 shows that the concentration of H2O2 and the duration of bleaching affect the colour, odour, and tensile strength of the textile.
This example relates to the use of solvents for the odour and colour harmonization step during the manufacturing process of the non-woven textile. Ethanol, acetone and chlorine treatment, as non-limiting examples, were carried out with 300% (v/v) solvent in a closed vessel at 25° C. for 120h with continuous stirring. The pH of the solution is preferably adjusted to pH 3 with a weak organic acid, acetic acid for example. The assessments of degree of offensiveness in regard to colour and odour were carried out by a panel of organoleptically-trained experts. The degree of offensiveness of the odour and colour are given values between 0 and 10, in which 0=no odour and 10=extremely odorous. Table 6 shows that the pH of the solution affects both the product colour and the odour.
Density-modifying agents are added in the manufacturing process of the non-woven textile. As an example, at least one complex non-water-soluble carbohydrate or lignocellulosic fibre is added as density-modifying agent to the pomace. As seen in Table 7, the type of lignocellulosic fibre chosen can affect the tensile strength of the non-woven textile. The type of lignocellulosic fibre is also evaluated based on its adhesion potential with apple pomace. The adhesion potential is important for the mixing during the manufacturing of the non-woven textile. The assessments are carried out by a panel of organoleptically trained experts. The degree of adhesion is given values from 0 to 10 (0=no adhesion; 10=extreme adhesion).
In addition to lignocellulosic fibres, the textile may contain other insoluble carbohydrates, water-soluble carbohydrates, and proteins. The soluble carbohydrate can constitute up to 20% (w/w) of the final composition of the textile. The protein can constitute up to 30% (w/w) of the final composition of the textile. Table 8 summarizes the influence of addition of different carbohydrates and proteins on tensile strength of the apple non-woven textile. To further increase the strength of the textile, enzymatic cross-linking reaction can be performed. In one embodiment, the enzyme transglutaminase was used to crosslink soy protein. The transglutaminase and soy protein were added to the sample containing apple pomace, 3% soft wood fibres and 3% sucrose at 35° C. The sample then was mixed and dried at 35° C. for 6 h.
In another embodiment natural latex milk is used as density-modifying agent. The use of natural latex milk as density-modifying agent affects the tensile strength of the product as depicted in Table 9. The addition of 9.6% and 19% natural latex milk in combination with 10% soft wood fibres and 23% sucrose to the dry matter of the milled apple pomace has been found to provide a high tensile strength between 8.95 to 9.90 N/mm2.
In another embodiment chemical cross-linking agents are added as density-modifying agents. Cross-linking agents have been found to alter the product strength. Exemplary, a mixture of citric acid and TiO2 was added to apple pomace together with 9% soft wood fibres and 23% sucrose, and thereafter heated at 80° C. for 1 h. The sample then was dried at 70° C. for 5 hours with or without curing at 165° C. for 5 minutes. This treatment resulted in a tensile strength of 7.82 N/mm2 for the final product. In another example, polyamidoamine epichlorohydrin (PAE) was added as cross-linking agent. For cross-linking PAE, the apple pomace was preferably bleached. The sample was dried at 40° C. for 6 h. As seen in Table 10, the addition of 8% soft wood fibres, 3% sucrose and 2% PAE (percentage of PAE based on the weight of the soft wood fibres) to the dry matter of milled apple pomace results in a product with tensile strength of 10.28 N/mm2.
The hydrophobic non-woven textile may additionally or alternatively include a humectant as a density-modifying ingredient. The humectant can constitute between 0.1% (w/w) to 2% (w/w) of the final composition of the textile and helps to preserve moisture content of the textile. The use of glycerol as a humectant was tested. Glycerol at concentrations 0% (w/w), 0.75% (w/w) or 1.5% (w/w) was added to the mixture containing milled apple pomace, 9% soft wood fibres, and 23%, 17.25% or 11.5% sucrose. The mixtures were heated at 70° C. for 2h and dried at 70° C. for 5h. As seen in Table 11, the treatment of the present embodiment adversely affected the tensile strength of the textile, however, improved the moisture retention in the apple pomace-based non-woven textile.
The process disclosed in the present invention includes forming and drying as parts of manufacturing the non-woven pomace-based textile. In one embodiment, biodegradable cellulose acetate frames are used for forming the textile. Therein, the sample is dried at 30° C. under a free flow of air until the moisture content in the non-woven textile is reduced to 20%. The temperature setting for drying different samples can differ for each sample composition. Examples of drying temperature settings with regards to product composition are given in Table 12.
The non-woven pomace-based textile achieved by the process disclosed in the present inventive concept is coated with a hydrophobic polymer to increase water resistance and to control moisture transport. One embodiment exemplifies the use of the polymer-based coatings polyvinyl butyrate (PVB) and a polymer emulsion in the presence and absence of corona treatment to improve coating adhesiveness. As seen in Table 13, a coating of the polymer emulsion followed by a layer of PVB, with (PVB corona) or without corona treatment (PVB), showed appreciable water resistance of the textile, resulted in a matte finish of the textile, and in good adhesiveness to the non-woven textile.
The aqueous liquid repellency test is carried out according to DS/ISO 23232:2009. The degree of aqueous liquid repellency is given values from 0 to 8 (0=not aqueous liquid repellent; 8=a surface tension of <24.0 dyne/cm, which is seen as highly aqueous liquid repellent).
The non-woven pomace-based textile achieved by the process disclosed in the present inventive concept may be used to form a composite material by attaching a textile backing to the finished non-woven textile using a certain adhesive solution. As an example, at least one layer of textile is attached as a backing. As seen in Table 14, the types of woven textile backing can affect the tensile strength of the non-woven textile. The type of textile backing is also evaluated based on the tear strength, measured in newtons (N) of the composite non-woven textile. The tear strength is important for the durability of the final composite material. The tear strength assessments are carried out and evaluated according to the standard ISO 3377-1-2016. The adhesion used for the embodiments listed in Table 14-16 is ester acrylic copolymer. As seen in Tables 14 and 15, the tear strength varies according to the types of backing textile used, e.g. when using linen plain woven textile the composite material has a high tear strength of 30.85 N (Table 14), whereas e.g. the use of cotton wrap knitted textile as backing for the composite non-woven textile results in a tear strength of 7.52 N (Table 15).
IThe textile is composed of a mixture of 54% cotton and 46% polyester.
Alternative textiles to the woven and knitted textiles listed in Tables 14 and 15, respectively, were also tested. The tear strengths of polyester tulle textile and natural fiber non-woven textile is shown in Table 16. For this experiment, the natural fiber was composed of 50% cotton and 50% soy.
| Number | Date | Country | Kind |
|---|---|---|---|
| PA 2019 70770 | Dec 2019 | DK | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/DK2020/050369 | 12/16/2020 | WO |
