Process for manufacturing a leather-like material from fruit, in particular bananas – material and associated products

Abstract

The present invention relates to a method for manufacturing a leatherette-type material in the form of a sheet or plate. According to the invention, - a puree of pulp and pericarp of at least one type of fruit containing water-insoluble fibers is produced; said puree is heated to a temperature greater than or equal to 70°C and less than or equal to 140°C; at least one vegetable oil capable of polymerizing and optionally at least one water-soluble polysaccharide capable of forming a gel and / or an emulsifier are added while mixing; a layer is formed with said mixture obtained, optionally on a textile sheet, and each face of said layer is dehydrated. The invention also relates to the material obtained and to products containing this material.

Description

Title of the invention: Method for manufacturing a leatherette-type material from fruit, in particular bananas - material and associated products Technical field

[0001] The present invention relates to a method for manufacturing a leatherette type material from fruit, in particular bananas and more particularly overripe bananas unsuitable for sale.

[0002] The present invention also relates to the material thus obtained and to the products containing this material. Technological background

[0003] Leather is a polluting material, particularly due to the tanning required to preserve the skin, which uses metal ions, particularly chromium ions.

[0004] Furthermore, intensive livestock farming is also a source of water pollution and generates significant quantities of greenhouse gases.

[0005] There are synthetic materials that replace leather (imitation leather). They are often derived from petrochemicals and are therefore also polluting.

[0006] More ecological alternatives to leather or synthetic materials have already been proposed.

[0007] Thus, document WO 2022 / 079284 A1 describes a process for manufacturing a leatherette based on vegetable proteins, in particular gluten and bean proteins to which vegetable tannins from cashew, grape or chestnut are added, as well as glycerol.

[0008] This process uses processed raw materials which are expensive and also have an impact on the environment due to their processing.

[0009] An aim of the present invention is to provide a method of manufacturing a material of the imitation leather type which has a limited environmental impact.

[0010] Another aim of the present invention is to propose a method which uses materials of plant origin and in particular fruits whose degree of ripening means that they are no longer marketable.

[0011] Another object of the present invention is to provide a leatherette type material which is hydrophobic without necessarily requiring the addition of a finishing layer making it hydrophobic.

[0012] Summary of the present invention

[0013] The present invention relates to a method of manufacturing a si-type material milicuir in the form of a sheet or plate, according to which, in a characteristic manner: • - a puree of pulp and pericarp of at least one type of fruit is produced containing water-insoluble fibers; • optionally water is added to the said puree • the said puree is heated to a temperature greater than or equal to 70°C and in less than or equal to 140°C; • at least one vegetable oil capable of polymerizing and optionally at least one water-soluble polysaccharide capable of forming a gel and / or an emulsifier are added while mixing; • a layer is formed with the mixture obtained, possibly on a sheet of textile, and • each face of said layer is dehydrated at a temperature greater than or equal to 40°C and less than or equal to 150°C, possibly under vacuum, until a solid sheet / plate is obtained.

[0014] The temperature below 140°C helps to avoid the Maillard reaction in the mixture. The minimum temperature helps to destroy any microorganisms present that could harm the durability of the material.

[0015] When heating the puree, the cell walls of the fruit are broken; they thus release the sugars, minerals and pectins they contain. During heating, the same reactions as when cooking jam take place. The pectins gel the water and the soluble compounds dissolved in it; the sugars also contribute to the thickening of the mixture. The polysaccharide will further gel the mixture if it does not contain enough pectin or starch. The oil, by polymerizing, will create a network of water-insoluble polymers / oligomers through the aqueous gel and the insoluble fibers trapped there. The emulsifier, when present, allows the good dispersion of the vegetable oil in the puree or the puree and water mixture and therefore promotes the homogeneity of the final material.The final result is a solid, non-porous material that resists traction and tearing due to the presence of insoluble plant fibers and the equally insoluble polymer formed by the oil, and which forms a solid gel.

[0016] Advantageously, the additives are added when the temperature of the mash or the water-mash mixture is 90°C.

[0017] The dehydration temperature affects the thickness of the final material. The more the gel is dehydrated, the thinner the material becomes (water is evaporated) and the more hydrophobic it becomes. However, beyond a certain dehydration, the material can become hygroscopic, especially when it contains excess glycerol. Dehydration completes the polymerization of the vegetable oil and must therefore be carried out with caution in order to obtain sufficient and homogeneous polymerization of the oil. in the viscous mixture which then forms a gel, while removing water from the latter so as to solidify it further. The dehydration temperature may be, for example, greater than or equal to 100°C and for example equal to 110°C.

[0018] Preferably, the mixture is dehydrated until the thickness of the plate / sheet is at least equal to 35%, preferably 30%, of the thickness of the initial mixture layer.

[0019] Insoluble fibers are or include lignin, cellulose, and hemicellulose fibers.

[0020] Advantageously, said mixture also contains pectins, starch, sugars, magnesium and calcium, and optionally ethanol and / or melanin.

[0021] The aforementioned ions promote the formation of inter-molecular bonds between the pectins, thus creating a network which reinforces that formed by the polymerized oil.

[0022] The fruit is not limited according to the invention. Preferably, it is a fruit unfit for consumption due to its over-ripening. The puree may thus contain ethanol and / or melanin.

[0023] Advantageously, the at least one type of fruit is the dessert banana.

[0024] Tons of bananas considered overripe are in fact thrown away every year in Europe. The process of the invention thus allows the use of fruits that are considered waste.

[0025] The textile is not limited according to the invention. It may be a knit, a woven fabric or a non-woven fabric. Advantageously, said textile sheet is chosen from cotton textiles, linen textiles, hemp textiles and linen and cotton, linen and hemp and cotton and hemp textiles. Linen or textiles containing linen are preferred because linen gives greater tear resistance to the material of the invention.

[0026] The vegetable oil capable of polymerizing is not limited according to the invention. It may be an oil which polymerizes by reaction with oxygen in the air or an oil which polymerizes under heat. Indeed, heating can initiate the polymerization reaction, which will continue during drying, inside the material, protected from air.

[0027] The vegetable oil is not limited according to the invention. It can be chosen from linseed oil, rapeseed oil, soybean oil, olive oil, perilla oil, chia oil, tung oil, hemp oil, walnut oil and mixtures thereof.

[0028] Preferably, linseed oil is used, which is a drying oil and which may be non-food grade.

[0029] Advantageously, said polysaccharide is chosen from xanthan gum, gum arabic, dextran, rhamsan, succinoglycan, guar gum, fenugreek gum, tara gum, locust bean gum, cassia gum, carrageenans, in particular iota carrageenans and mixtures thereof and / or said emulsifier is chosen from polyols, in particular mannitol, glycerol, sorbitol and mixtures thereof.

[0030] These polysaccharides allow, in the presence of water, the production of a gel. They increase the viscosity and contribute to the elasticity of the material obtained and its soft feel.

[0031] Iota carrageenans also make it possible to control the syneresis of the gel contained / constituting the material of the invention. They make it possible to obtain a flexible gel and avoid excessive dehydration or excessively rapid dehydration of the gel.

[0032] Preferably, guar gum and xanthan gum are used in combination, which exhibit synergy for the formation of a gel when combined. In addition, xanthan gum also allows the formation of a gel in an acidic medium;

[0033] Advantageously, the mixture also contains an emulsifier, in particular a polyol, in order to disperse the polymerizable vegetable oil well in the water. Glycerol makes it possible to stabilize the oil / water mixture and thus to obtain a homogeneous polymerization of the oil. In addition, the secondary alcohol function of the glycerol can be esterified by a fatty acid contained in the vegetable oil. Esters are then formed at the same time as the polymerization of the vegetable oil, which make the mixture more homogeneous, increase its viscosity and make it hydrophobic. Glycerol should not be used in too large a quantity because it is hygroscopic and therefore can harm the hydrophobicity of the material.

[0034] As an indication, the polymerizable vegetable oil is introduced in an amount such that it represents 2 to 3% by mass and preferably 2.5% by mass of the starting mixture of the process. It is preferably linseed oil.

[0035] As an indication, the glycerol is introduced in an amount such that it represents 1.0 to 2.5% by mass and preferably 1.5% by mass of the starting mixture used in the process of the invention.

[0036] As an indication, the xanthan gum is introduced in an amount such that it represents 0.25 to 1.5% by mass and preferably 0.75% by mass of the starting mixture of the process.

[0037] As an indication, the guar gum is introduced in an amount such that it represents 0.2 to 1% by mass and preferably 0.5% by mass of the starting mixture of the process.

[0038] As an indication, the iota carrageenans are introduced in a quantity such that they represent from 0.1% to 0.5% by mass of the mixture, and in particular 0.15%, 0.2 or 0.3% by mass of the mixture.

[0039] It goes without saying that the compounds which are contained in the starting mixture and which do not react chemically are contained in the imitation leather of the invention in different mass proportions due to the dehydration of the starting mixture used in the process. Compounds that do not react chemically include polysaccharides and polyols.

[0040] The present invention also relates to a leatherette in the form of a sheet / plate obtainable according to the process of the invention and which comprises at least a first layer of an aqueous gel containing sugars, water-insoluble plant fibers and water-insoluble oligomers or polymers originating from the polymerization of a vegetable oil and optionally xanthan and / or galactomannan and / or an emulsifier chosen from polyols, in particular glycerol, sorbitol, mannitol and mixtures thereof, in particular mixtures of sorbitol and glycerol.

[0041] The water-insoluble fibers have, for example, a size ranging from 60 pm to 10 mm and preferably from 3 mm to 7 mm.

[0042] The oligomers and / or polymers originating from vegetable oil form a network which confers both the hydrophobicity of the material and its mechanical properties of resistance to tearing, traction and bending, in particular.

[0043] The imitation leather of the invention is non-porous. The gel gives the material a leather-like appearance with a certain velvetiness and a touch close to that of leather. The surface is soft to the touch and its appearance is matte with a deep, more or less light brown color. The surface is homogeneous without roughness or defects. The material resembles oiled leather.

[0044] The thickness of the imitation leather sheet / plate is not limited according to the invention. It may, for example, be equal to or greater than 0.5mm and less than or equal to 3mm. It is preferably equal to or greater than 1.2mm and less than or equal to 2mm and in particular equal to 1.2mm, 1.23mm or 1.24mm.

[0045] The aforementioned thickness of the imitation leather of the invention is obtained with a 4mm thick layer of starting mixture. This sheet of imitation leather can be used in leather goods or for the manufacture of shoes or other.

[0046] Advantageously, the sheet or plate of imitation leather of the invention has a thickness greater than or equal to 1.0 mm and preferably equal to 1.2 mm, 1.23 mm or 1.24 mm, a contact angle greater than or equal to 90° and which has a tear strength measured according to the ISO 3377-2 standard greater than or equal to 50 N / m and / or a tensile strength oR measured according to the ISO 3376 standard greater than 12 MPa, in particular greater than or equal to 15 MPa, 17 MPa or 19 MPa.

[0047] The aforementioned tear resistance may be less than or equal to 85N / m or 90 N / m.

[0048] The aforementioned tensile strength may be less than or equal to 23 MPa.

[0049] According to a preferred embodiment, the imitation leather of the invention is obtained from of bananas; it therefore also contains calcium, phosphorus, magnesium and iron. Thus, the imitation leather of the invention may contain at least 50 mg of calcium, at least 70 mg and in particular 78 mg of phosphorus and at least 10 mg of magnesium per 100 g.

[0050] Advantageously, the imitation leather of the invention comprises a textile layer integral with said first layer and / or a finishing layer which covers said first layer.

[0051] The textile layer is preferably a linen or linen-containing fabric.

[0052] The topcoat may be a layer of vegetable oil, preferably a A layer of oil that polymerizes with oxygen in the air, such as linseed oil, which makes the leatherette even more hydrophobic. It can also be a layer of wax, such as camauba wax, jojoba wax, candelilla wax, rice wax, soybean wax, rapeseed wax, coconut wax, palm wax, sunflower wax, olive wax, jasmine wax, pine resin, or any other wax or resin. This finishing layer increases the hydrophobicity of the surface of the leatherette. It can also give it a shiny appearance.

[0053] The imitation leather of the invention may also contain a colorant (added at the same time as the other additives and with stirring), in particular a food coloring such as activated carbon. It may also contain quercetin which also gives it a black color.

[0054] The imitation leather of the invention can be embossed due to the presence of the gel (which can be permanently deformable) and printed.

[0055] According to a particular embodiment, the imitation leather of the invention contains from 2.89% to 4.33% by mass of polymers / oligomers originating from the polymerization of the oil. It preferably contains 3.6% by mass of oligomers / polymers which preferably originate from linseed oil.

[0056] According to an embodiment which can be combined with the aforementioned embodiment, the imitation leather of the invention contains in mass percentage from 1.44% to 3.6% and preferably 2.7% by mass of polyol(s) and in particular glycerol.

[0057] According to another embodiment which can be combined with the other embodiments, the imitation leather of the invention contains in mass percentage from 0.79% to 4.33% of polysaccharide(s).

[0058] According to one variant, the imitation leather of the invention contains from 0.36% by mass to 2.17% by mass and preferably 1.08% by mass of xanthan gum.

[0059] According to another variant which can be combined with the previous one, it contains from 0.29% by mass to 1.44% by mass of guar gum and in particular 0.72% by mass of guar gum.

[0060] According to another variant combinable with each of the aforementioned variants, the si- The leatherette of the invention contains from 0.14% by mass to 0.72% by mass of carrageenans, preferably iota carrageenans. In particular, it may contain 0.2% by mass, 0.29% or 0.43% by mass of carrageenans, in particular iota carrageenans.

[0061] The present invention also relates to a product chosen from shoes, leather goods, in particular wallets, bags, office items, in particular desk pads, furniture items, in particular armchairs, sofas, wall panels, interior, seat and steering wheel coverings for motor vehicles and jewelry which comprises a portion of imitation leather according to the invention.

[0062] Definitions

[0063] The terms "polymerizable vegetable oil" designate any unsaturated and in particular polyunsaturated fatty acid as well as any mixture containing at least one unsaturated and preferably polyunsaturated fatty acid or consisting of unsaturated and preferably polyunsaturated fatty acids. Thus, the vegetable oil may comprise linoleic acid, alpha-linolenic acid, gamma-linolenic acid, dihomo-gamma-linolenic acid, arachidonic acid, eicosapentaenoic acid or docosahexaenoic acid or a mixture of at least two of these polyunsaturated fatty acids.

[0064] The term “gel” designates a solid containing macromolecules and / or polymers / oligomers forming a three-dimensional network distributed in a fluid.

[0065] The term “sheet” designates a plate which can be rolled on itself and form a roll. Brief description of the figures

[0066] [Fig.l] represents photographs of the samples of imitation leather according to the invention.

[0067] Description of the examples of embodiment

[0068] Method of the invention

[0069] Preparation of the mixture

[0070] 2 kg of ripe bananas deemed unfit for consumption are mixed with their skin. Water may be added to obtain a homogeneous mixture.

[0071] The mixture is heated to a temperature below 100°C and above 70°C for 15-25 min so as to destroy any microorganisms (bacteria and fungi, in particular) and to release the contents of the cells. This produces an aqueous and viscous puree containing sugars (fructose in particular), proteins, minerals and water-insoluble fibers, particularly from banana skins.

[0072] According to a first particular variant, the puree is left to cool to the temperature room temperature and possibly left to stand for 2-3 days. It is then heated to a temperature greater than or equal to 60°C and less than or equal to 90°C before adding the additives indicated in Table 1 below.

[0073] According to a second variant, the puree is allowed to cool to a temperature greater than or equal to 60°C and less than or equal to 90°C and the additives are added.

[0074] In both variants, the additives are added while the puree is being mixed (mechanically stirred).

[0075] In both variants, it is possible to filter the puree before adding the additives.

[0076] The gelling agents used are xanthan gum and agar-agar.

[0077] The plasticizers used are guar gum and iota carrageenans.

[0078] The colorant used is activated carbon powder or quercetin.

[0079] The polymerizable vegetable oil used is linseed oil.

[0080] The texturizing and emulsifying agents used are glycerin and sorbitol.

[0081] The elasticity enhancing agents used are natural rubber (cis polyisoprene) and rosin gum.

[0082] The textiles used are linen fabrics and cotton fabrics.

[0083] Formatting

[0084] The mixture obtained in the above-mentioned step is placed on a glass plate, covered with linen or cotton fabric. Then, two 4 mm thick glass plates are placed on either side of the fabric. A third plate is used to spread the mixture so as to make the surface homogeneous and smooth between the two glass plates placed on either side of the fabric. The purpose of using the two glass plates placed on either side of the fabric is to control the thickness of the layer of puree deposited on the fabric. A 4 mm layer of puree makes it possible to obtain a sheet that can be used for making shoes, gloves and clothing items, in particular.

[0085] Drying

[0086] The layer of puree formed is placed in an oven at a temperature greater than or equal to 60°C and less than or equal to 80°C for a few hours. After this first dehydration step, the plate / sheet formed between the glass plates can be detached. The second side of this plate / sheet is then dried at a temperature less than or equal to 60°C and greater than or equal to 20°C. The plates thus obtained are then used for the mechanical characterization of the material and the measurement of the contact angle.

[0087] Characterization of banana puree

[0088] The sugar content in the banana puree was measured using a kitchen refractometer. It is the same before and after cooking, i.e. greater than or equal to 15% and less than or equal to 20% and preferably equal to 17% or 19% by mass.

[0089] The following table 1 groups together certain constituents of the ripe banne which was used in the process of the invention. For comparison, the levels of the same constituents in unripe banana are also indicated. The percentages are percentages by mass.

[0090] [Tables 1] Constituents % in ripe banana % in unripe banana Moisture content (%) 75.25 + 0.20 39.40 + 0.39 Ash (mg / 100g) 2.07 + 0.02 1.66 + 0.06 Protein (g / 100g) 3.25 + 0.20 1.75 + 0.20 Fat (g / 100g) 2.59 + 0.04 2.51 + 0.32 Crude fiber (g / 100g) 2.42 + 0.04 2.78 + 0.02 Total soluble sugars (g / 100g) 21.37 + 0.31 1.12 + 0.13 Polyphenols (mg / 100g) 725.00 + 20.41 506.25 + 15.30 Flavonoids (mg / lOOg) 126.00 + 20.41 131.00 + 0.81 Vitamins C (mg / lOOg) 0.54 + 0.004 0.55 + 0.01 Phytates (mg / lOOg) 0.3175 + 0.0002 0.0377 + 0.0002 Oxalates (mg / lOOg) 2.77 + 0.02 3.15 + 0.04 Calcium (mg / lOOg) 52.60 + 0.41 38.57 + 0.40 Phosphorus (mg / lOOg) 78.13 + 2.55 50.00 + 0.00 Iron (mg / lOOg) 1.00 + 0.20 1.00 + 0.20 Fructose (g / 100) 11.95 + 0.12 0.49+ 0.01 Magnesium (mg / 100g) 35 35 Reducing sugars 19.12 + 0.10 0.56 + 0.08 (g / 100g) Non-reducing sugars (g / 100g) 21.37 + 0.31 1.12 + 0.13 pectins 0.7% 1.2% Insoluble fiber 0.6% (without pericarp) 2.7% starch 2.6% 61.7

[0091] The pH of the mash is between 4 and 5 and in particular equal to 4.5.

[0092] The pectins of ripe bananas are highly degraded and their ability to form a network is to be questioned.

[0093] Bananas also contain melanin and ethanol due to their high ripeness. These are dessert bananas, not cooking bananas or plantains.

[0094] First embodiment: Formulation of the different mixtures

[0095] The different mixtures prepared and used for the formation of sheet / plate are grouped in the following table 2. The % are mass percentages. The water corresponds to the water added to the puree for mixing with the additives and / or to facilitate homogenization and / or possible filtration.

[0096] [Tables2] Puree (%) Water (ml / g) Glycerin (%) Linseed oil (%) Xanthan Gum Guar Gum (%) Carrageenan iota (%) FR 78.25 0.225 1.56 1.56 0.39 0.39 0.23 F0 78.25 0.225 0.00 0.00 0.00 0.00 0.00 F9 94.6 0.27 1.5 2.5 0.75 0.5 0.15% F10 94.45 0.27 2 2 0.75 0.5 0.3% F12 94.7 0.27 2 2.5 0.75 0.75 0.3% F13 94.1 0.27 2 2.5 0.75 0.5 0.15% F14 95 0.225 1.5 2.5 0.75 0.5 0.00% F18 93.5 0.27 2 2.0 0.50 2.0 0.00% F20 93.5 0.27 2.5 2.5 0.25 1.1 0.15

[0097] [Fig.l] shows various samples of imitation leather according to the invention. It can be seen that they have a smooth and uniform surface, slightly shiny, black in color. (obtained by adding quercetin or activated charcoal).

[0098] Characterization of the plate / sheet materials obtained

[0099] Measurement of hydrophobicity: measurement of the contact angle

[0100] Measuring the contact angle with a drop of water makes it possible to determine the hydrophilic or hydrophobic nature of the surface of the material. Indeed, depending on the value of the contact angle, the surface can be hydrophilic, partially hydrophilic, hydrophobic or superhydrophobic.

[0101] - For 0°< 0 < 30°: hydrophilic surface

[0102] - For 30°< 0 < 90°: partially hydrophilic surface

[0103] - For 90°< 0 < 110°: hydrophobic surface

[0104] - For 110< 0 <180°: superhydrophobic surface

[0105] The contact angle measurement was carried out using a contact angle goniometer model OCA 15EC connected to a computer. Using the SCA20-Software for OCA and PCA software installed on the computer, a 3ql drop of water is placed on the surface of the material and after 2 seconds of waiting, a photo of the drop is taken. The angle is measured on the left and right and then the average is calculated according to the formula 0 = (0(left)+ 0(right)) / 2. For each material, this operation is repeated 10 times and the contact angle of the material corresponds to the average of the 10 measures.

[0106] Mechanical tests

[0107] Tensile strength

[0108] The tensile strength test was carried out according to ISO 3376 using the SHIMADZU tensile testing machine. A test piece is cut with a die as specified in ISO 2419.

[0109] Using a vemier caliper, the width of each specimen and the distance between the jaws of the tensile machine were measured. As for the thickness of the specimens, it was measured using a Mitutoyo thickness gauge. Once the specimen is ready, it is fixed to the jaws of the tensile machine and stretched at a specified speed until the specimen breaks. The tensile strength value is calculated using formula (1) and the elongation at break using formula (2).

[0110] “Formula 1 F max ,* x £ / O ~ sgj [YES] Formula 2 x 100 (2)

[0112] In formulas 1 and 2, Fmax is the maximum force recorded in newtons (N), f is the average width of the specimen in millimeters and e is the average thickness of the specimen in millimeters. oR represents the tensile strength and is expressed in MPa or N / mm2 (IMPa = 1 N / mm2). eR is the elongation at break in %, Lo is the initial spacing of the jaws of the tensile machine in millimeters, L is the spacing, in millimeters, of the jaws after the rupture of the specimen.

[0113] In total for each material, 6 test pieces are required, three cut in the longitudinal direction and three in the transverse direction. The tensile strength of the material corresponds to the average tensile strength of the 6 test pieces.

[0114] Tear resistance

[0115] The tearing of vegetable leather imitations was studied using a SHIMADZU tensile testing machine according to ISO 3377-2. The study consisted of cutting out, using a die conforming to the specifications of ISO 2419, a rectangular test piece, pierced with a hole of specified shape and placed on the upwardly facing ends of a pair of test piece holders fixed to the jaws of the tensile testing machine.

[0116] The maximum force required to tear the specimen is recorded. The tear strength is calculated according to formula (3).

[0117] In total for each material, 6 test pieces are required, three cut in the longitudinal direction and three in the transverse direction.

[0118] Formula 3 Fd Rd ~ (3) £

[0119] Rd denotes the tear strength in N / mm; Fd denotes the maximum force required to tear the specimen in N and e denotes the thickness of the specimen in mm.

[0120] Results

[0121] Contact angle measurement

[0122] [Tables3] Materials 0(°) with a drop of water Standard deviation FR 83.2 4.8 F0 53.3 13.7 F9 81.2 6.8 F10 66.7 5.3 F12 68 7 F13 79.9 7.2 F14 95.4 3.1 F18 105.2 8.7 F20 96.5 1.5

[0123] It can be seen from the results in Table 3 that materials F18, F14 and F20 are the most hydrophobic.

[0124] Tear resistance results

[0125] [Tables4] Thickness (mm) Tear force (N) ISO 3377-2 Standard deviation Tear strength (N / mm) FR 0.86 17.94 1.87 20.9 F9 1.23 57.18 5.78 46.5 F10 1.37 52.30 6.72 38.2 F12 1.54 62.66 8.61 40.7 F13 1.29 62.06 11.92 48.1 F14 1.28 61.15 9.8 49.7 F18 1.19 71.3 11.3 57.5 F20 1.01 53.53 5.19 53

[0126] It is found that the final material in the form of a plate / sheet has a lesser thickness than the formed composition layer. Nevertheless, all the sheets / plates have a thickness usable in the leather industry.

[0127] Materials F14, F18 and F20 are those which most meet expectations in qualitative and quantitative terms. Indeed, they have a good feel, a good texture, a good flexibility and flexing in the hand and in quantitative tests, they are all hydrophobic and have a tear resistance above that of the F9 material used as a reference. All these materials have tear resistance values ​​above the minimum values ​​required for footwear, bag, glove and clothing applications.

[0128] These results also show that the tear resistance depends on the type of fabric on which the composition layer is deposited. Tear resistance tests on the cotton fabric without formulation and on the linen fabric without formulation were carried out. The linen fabric has a tear resistance 3x higher than that of the cotton fabric.

[0129] The material of formulation F9 proves to be satisfactory in terms of qualitative and quantitative properties. Indeed, it has a good texture, a good feel, flexibility and hand flexion which allow its use in leather goods as well as good tensile strength. It is also relatively hydrophobic.

[0130] Tensile strength tests of the F9 formulation material were carried out. They are grouped in Table 5 below. [Tables 5] Test specimen Width (mm) Thickness (mm) oR ( MPa) ISO 3376 Standard deviation Longitudinal direction 1 4.2 1.14 20.89 Longitudinal direction 2 4.2 1.15 17.61 Longitudinal direction 3 4.2 1.18 9.65 Transverse direction 1 4.2 1.11 10.42 Transverse direction 2 4.2 1.11 10.19 Transverse direction 3 4.2 1.13 9.45 Average 4.2 1.14 13 4.48

[0131] It is found that the value of the tensile strength of the material of formulation F9 is of the order of 13 MPa. This value is similar to that of certain brands of commercial vegetable leatherette.

[0132] Tensile strength tests of materials F14, 18 and F20 were carried out as indicated for material F9. The results are seen in the following Table 6. [Tableauxô] Materials Thickness (mm) oR (MPa) ISO 3376 F14 1.24 19.9 ± 2.3 F18 1.42 6.55 F20 1.24 12.5 ± 4 F9 1.14 13

[0133] It is found that it is the material of formulation F14 which has the greatest tensile strength. However, the material F20 also has a tensile strength which allows it to be used in all uses of an imitation leather.

[0134] Second embodiment

[0135] Other formulations were tested. They are grouped in Tables 7 and 8 below. Table 8 lists the additives used in the different formulations. The same operating protocol was used except for one sample whose drying temperature is explicitly mentioned. [Tables?] Puree (%) Water (ml / g) F25 93.4 0.27 F26 93.4 0.27 F27 93.1 0.27 [Tables 8] Glycerol (%) Sorbitol Linseed oil (%) Agar-agar (%) Guar gum (%) Color (%) Natural rubber (%) Rosin gum (%) F25 0.00 2.00 2.00 0.50 0.8 0 0.8 0.5 F26 2.00 0.00 2.00 0.50 0.8 0 0.8 0.5 F27 2.00 0.00 2.00 0.50 0.8 0.3 0.8% 0.5

[0136] The colorant used is quercetin.

[0137] The same contact angle and tear resistance measurement tests were carried out. The results are grouped in the following tables 9 and 10. The same protocols were used.

[0138] Contact angle measurement [Tables 9] Materials 0(°) with a drop of water Standard deviation F25 52.5 3.1 F25 (Dried at 110°C for 30min) 82.7 5.9 F26 49.4 3.7 F27 74.8 6.4

[0139] It is noted that increasing the drying temperature makes the material more hydrophobic but that it still remains partially hydrophilic.

[0140] Measurement of tear strength and thickness

[0141] [Tables 10] Material Thickness (mm) Tearing force (N) ISO 3377-2 Standard deviation Tearing strength (N / mm) F25 (Linen France) 1.2 75.5 11.84 63 F25 (Linen) 1.2 46.2 9.16 38.5 F26 (Linen France) 1.3 70.4 7.37 54.1 F27 (Cotton fabric) 1.3 17.4 2.38 13.4

[0142] Again, it is found that the tear resistance is related to the underlay textile. It is also found that the use of sorbitol as a texturing agent provides less tear resistance than glycerin.

[0143] Results of resistance tests of the material referenced FR

[0144] A bending test according to ISO 5402-1

[0145] direction 1 hole at 30000 flexions; direction 2 hole at 200000 flexions.

[0146] The tables below summarize the results of the various tests. [Tableauxll] Tensile strength and percentage elongation - EN ISO 3376: 2020 result unit Size Normal Conditioning and testing atmosphere 23°C (+ / - 2°C) & 50% RH (+ / -5%) Longitudinal direction - thickness 1.01 mm Transverse direction - thickness 1.01 mm Longitudinal direction - Average tensile strength 5.5 N / mm2 Transverse direction - Average tensile strength 8.5 N / mm2 Tensile strength - average 7.0 N / mm2 Longitudinal direction - Elongation under maximum force - average value 29% Transverse direction - Elongation under maximum force - average value 24% Elongation under maximum force - average value 27% [Tables 12] Dry bending (BALLYFlexion) - ISO 5402-1:2017 Direction 1- dry bending- number of cycles 2000 Direction 1- dry bending- de- Visible cracks at gradations observed by eye Direction 2- dry bending- number of cycles 1000 Direction 1- dry bending- de- Visible cracks at gradations observed by eye [Tables 13] Martindale dry abrasion resistance on uppers, linings and insoles - EN 13520:2001 / Al:2004 Applied pressure 12kPa Abrasive Abrasive combed wool Number of cycles to first degradation 10000 Number of cycles to first hole >256000 Total number of cycles 25600 Final observations 1st degradation: partial abrasion of the specimen. / / at 25600 cycles: slight abrasion of the material, black over the entire specimen. No hole [Tables 14] Tear - single edge - EN ISO 3377-1: 2011 Conditioning atmosphere 23°C / 50%RH Thickness 0.80 mm Tear force - Longitudinal direction (1) 6.8 N Tear force - Longitudinal direction (2) 7.3 N Tear force - Longitudinal direction (3) 6.5 N Average longitudinal 6.9 N Tear force - Transverse direction (1) 5.1 N Tear force - Transverse direction (2) 4.7 N Tear force - Transverse direction (3) 4.4 N Average transverse 4.7 N Average tear force 5.8 N

Claims

Claims

1. Method for manufacturing a material of the imitation leather type in the form of a sheet or plate, characterized in that: - a puree of pulp and pericarp of at least one type of fruit containing fibers not soluble in water is produced; - optionally water is added to said puree - said puree is heated to a temperature greater than or equal to 70°C and less than or equal to 140°C; - at least one vegetable oil capable of polymerizing and optionally at least one polysaccharide soluble in water and capable of forming a gel and / or an emulsifier are added while mixing; - a layer is formed with said mixture obtained, optionally on a textile sheet, and - each face of said layer is dehydrated at a temperature greater than or equal to 40°C and less than or equal to 150°C until a solid sheet / plate is obtained.

2. Method according to claim 1, characterized in that said puree further contains pectins, starch, sugars, magnesium and calcium and optionally ethanol and / or melanin.

3. Method according to claim 1 or 2, characterized in that the at least one type of fruit is dessert banana.

4. Method according to any one of claims 1 to 3, characterized in that said textile sheet is chosen from cotton textiles, linen textiles, hemp textiles, linen and cotton textiles, linen and hemp and cotton and hemp.

5. Method according to any one of the preceding claims, characterized in that said vegetable oil capable of polymerization is chosen from linseed oil, rapeseed oil, soybean oil, olive oil, perilla oil, chia oil, Chinese wood oil, hemp oil, walnut oil and mixtures thereof.

6. Process according to any one of the preceding claims, characterized in that said polysaccharide is chosen from xanthan gum, gum arabic, dextran, rhamsan, succinoglycan, guar gum, fenugreek gum, tara gum, locust bean gum, cassia gum and carrageenans, in particular iota carrageenans and mixtures thereof, and / or in that said emulsifier is chosen from polyols, in particular mannitol, glycerol, sorbitol and mixtures thereof.

7. Imitation leather in sheet / plate form obtainable according to the method according to any one of the preceding claims, characterized in that it comprises at least a first layer of an aqueous gel which contains sugars, water-insoluble plant fibers and water-insoluble oligomers or polymers originating from the polymerization of a vegetable oil and optionally xanthan and / or galactomannan and / or an emulsifier chosen from polyols, in particular glycerol, sorbitol, mannitol and mixtures thereof.

8. Imitation leather according to claim 7, characterized in that it has a thickness greater than or equal to 1.0 mm, preferably equal to 1.2 mm, in particular equal to 1.23 or 1.24 mm, a contact angle greater than or equal to 90° and a tear strength measured according to standard ISO 3377-2 greater than or equal to 50 N / m and / or a tensile strength oR measured according to standard ISO 3376 greater than 12 MPa, in particular greater than or equal to 15 MPa, 17 MPa or 19 MPa.

9. Imitation leather according to claim 7 or 8, characterized in that it comprises a textile layer on which said first layer is arranged and / or a finishing layer which covers the free surface of said first layer.

10. Product chosen from shoes, leather goods, in particular wallets, bags, office items, in particular desk pads, furniture items, in particular armchairs, sofas, wall panels, interior, seat and steering wheel coverings for motor vehicles and jewelry, characterized in that it comprises a portion of imitation leather according to any one of claims 7 to 9.

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