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 leather-like material in sheet or plate form. According to the invention, a puree is made from the pulp and pericarp of at least one type of fruit containing water-insoluble fibers; 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 polymerization and optionally at least one water-soluble polysaccharide capable of forming a gel and / or an emulsifier are added by mixing; a layer is formed with said mixture, optionally on a textile sheet, and each side of said layer is dehydrated. The invention also relates to the material obtained and to products containing this material.

Description

Title of the invention: Process for manufacturing a leather-like material from fruit, in particular bananas - material and associated products technical field

[0001] The present invention relates to a method for manufacturing a imitation leather type material from fruits, in particular bananas and more particularly overripe bananas unsuitable for marketing.

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

[0003] Leather is a polluting material due in particular to the tanning required for the preservation of the skin, which uses metallic ions, in particular chromium ions.

[0004] Furthermore, intensive 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 environmentally friendly alternatives to leather or synthetic materials have already been proposed.

[0007] Thus, document WO 2022 / 079284 Al describes a process for manufacturing a imitation leather based on vegetable proteins, in particular gluten and bean proteins to which vegetable tannins from catechu, 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 object of the present invention is to propose a method for manufacturing a imitation leather type material which has a limited environmental impact.

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

[0011] Another object of the present invention is to propose a imitation leather 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 for manufacturing a si-type material microleather in the form of a sheet or plate, according to which, characteristically: • - a puree is made from the pulp and pericarp of at least one type of fruit containing fibers that are not soluble in water; • Optionally, water is added to the purée. • 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 suitable for polymerization is added by mixing, and possibly at least one water-soluble polysaccharide suitable for forming a gel and / or an emulsifier; • a layer is formed with the said mixture obtained, possibly on a sheet of textile, and • Each side 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] A temperature below 140°C prevents the Maillard reaction in the mixture. This minimum temperature destroys any microorganisms present that could compromise the material's durability.

[0015] When the purée is heated, the cell walls of the fruit are broken, releasing the sugars, minerals, and pectins they contain. During heating, the same reactions occur as when making jam. The pectins gel the water and the soluble compounds in solution within it; the sugars also contribute to thickening the mixture. The polysaccharide will further gel the mixture if it does not contain enough pectin or starch. As the oil polymerizes, it creates a network of water-insoluble polymers / oligomers through the aqueous gel and the insoluble fibers trapped within it. The emulsifier, when present, ensures the proper dispersion of the vegetable oil in the purée or the purée-water mixture, thus promoting the homogeneity of the final material.The result is a solid, non-porous material that resists tension and tearing due to the presence of insoluble plant fibers and the equally insoluble polymer formed by the oil, which forms a solid gel.

[0016] Advantageously, the additives are added when the temperature of the puree or the water-puree 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 (as water evaporates) and the more hydrophobic it becomes. However, beyond a certain point of dehydration, the material can become hygroscopic, particularly when it contains excess glycerol. Dehydration completes the polymerization of the vegetable oil and must therefore be carried out carefully to ensure sufficient and homogeneous polymerization of the oil. in the viscous mixture which then forms a gel, while removing water from it to further solidify it. The dehydration temperature can 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 further contains pectins, starch, sugars, magnesium and calcium, and possibly ethanol and / or melanin.

[0021] The aforementioned ions promote the formation of intermolecular bonds between 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 being overripe. The puree may therefore contain ethanol and / or melanin.

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

[0024] Tons of bananas deemed overripe are indeed thrown away each year in Europe. The process of the invention thus allows for the use of fruit that is considered waste.

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

[0026] The vegetable oil suitable for polymerization is not limited according to the invention. It may be an oil that polymerizes by reaction with atmospheric oxygen or an oil that polymerizes when heated. 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 can be non-food grade.

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

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

[0031] Iota carrageenans also allow for the control of syneresis of the gel contained in / constituting the material of the invention. They allow for the formation of a flexible gel and prevent excessive or too rapid dehydration of the gel.

[0032] Preferably, guar gum and xanthan gum are used in combination, as they exhibit synergy for gel formation when combined. Furthermore, xanthan gum also allows gel formation in an acidic environment;

[0033] Advantageously, the mixture also contains an emulsifier, in particular a polyol, to ensure good dispersion of the polymerizable vegetable oil in water. Glycerol helps stabilize the oil / water mixture and thus achieve homogeneous polymerization of the oil. Furthermore, the secondary alcohol group of glycerol can be esterified by a fatty acid contained in the vegetable oil. Esters are then formed simultaneously with the polymerization of the vegetable oil, making the mixture more homogeneous, increasing its viscosity, and rendering it hydrophobic. Glycerol should not be used in excessive quantities because it is hygroscopic and can therefore impair the hydrophobicity of the material.

[0034] By way of example, the polymerizable vegetable oil is introduced in such a quantity that it represents 2 to 3% by mass and preferably 2.5% by mass of the starting mixture of the process. This is preferably linseed oil.

[0035] For the sake of indication, glycerol is introduced in such a quantity 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, xanthan gum is introduced in such a quantity 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, guar gum is introduced in such a quantity that it represents 0.2 to 1% by mass and preferably 0.5% by mass of the starting mixture of the process.

[0038] By way of example, the iota carrageenans are introduced in such a quantity 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 The mass proportions vary 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 imitation leather in the form of a sheet / plate which can be obtained according to the process of the invention and which comprises at least a first layer of an aqueous gel containing sugars, water-insoluble vegetable fibers and water-insoluble oligomers or polymers and obtained from the polymerization of a vegetable oil and optionally xanthan gum and / or galactomannan and / or an emulsifier selected 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 µm to 10 mm and preferably from 3 mm to 7 mm.

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

[0043] The imitation leather of the invention is non-porous. The gel gives the material an appearance similar to leather, with a certain velvety feel and a touch close to that of leather. The surface is soft to the touch and has a matte finish with a deep, more or less light brown color. The surface is homogeneous, without any 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 0.5 mm and less than or equal to 3 mm. Preferably, it may be equal to or greater than 1.2 mm and less than or equal to 2 mm, and in particular equal to 1.2 mm, 1.23 mm or 1.24 mm.

[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 items.

[0046] Advantageously, the imitation leather sheet or plate 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 resistance measured according to ISO 3377-2 greater than or equal to 50 N / m and / or a tensile strength oR measured according to ISO 3376 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 can 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 attached to said first layer and / or a finishing layer which covers said first layer.

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

[0052] The topcoat can be a layer of vegetable oil, preferably a A layer of oil that polymerizes with atmospheric oxygen, such as linseed oil, makes the imitation leather even more water-repellent. It can also be a layer of wax, such as camauba wax, jojoba wax, candelilla wax, rice wax, soy 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 water repellency of the imitation leather's surface and can also give it a glossy appearance.

[0053] The imitation leather of the invention may also contain a colorant (added at the same time as the other additives and under agitation), in particular a food coloring such as activated charcoal. 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 obtained from the polymerization of the oil. It preferably contains 3.6% by mass of oligomers / polymers, which preferably come from linseed oil.

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

[0057] According to another embodiment combinable with the other embodiments, the imitation leather of the invention contains by 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 combinable 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 microleather of the invention contains from 0.14% by mass to 0.72% by mass of carrageenan, preferably iota carrageenan. In particular, it may contain 0.2% by mass, 0.29% or 0.43% by mass of carrageenan, especially iota carrageenan.

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

[0062] Definitions

[0063] The term “polymerizable vegetable oil” means any unsaturated fatty acid, and in particular any polyunsaturated fatty acid, as well as any mixture containing at least one unsaturated fatty acid, preferably polyunsaturated, or consisting of unsaturated fatty acids, preferably polyunsaturated. Thus, the vegetable oil may include 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” refers to a solid containing macromolecules and / or polymers / oligomers forming a three-dimensional network distributed in a fluid.

[0065] The term "sheet" refers to a plate that can be rolled up on itself and form a roll. Brief description of the figures

[0066] Fig. 1 shows photographs of the imitation leather samples according to the invention.

[0067] Description of examples of implementation

[0068] Method of the invention

[0069] Preparation of the mixture

[0070] 2 kg of ripe bananas deemed unfit for consumption are blended with their peel. 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 minutes in order to destroy any microorganisms (bacteria and fungi, in particular) and to release the cell contents. This yields a viscous, aqueous puree containing sugars (especially fructose), proteins, minerals, and water-insoluble fiber, notably from banana peels.

[0072] According to a first particular variant, the puree is allowed to cool until the temperature room temperature and possibly left to rest 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 (mechanical stirring).

[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 carrageenan.

[0078] The colorant used is activated charcoal 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 aforementioned step is deposited onto a glass plate covered with linen or cotton fabric. Next, 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 pulp deposited on the fabric. A 4 mm layer of pulp produces a sheet suitable for making shoes, gloves, and clothing, among other things.

[0085] Drying

[0086] The resulting layer of puree is placed in an oven at a temperature of 60°C or higher and 80°C or lower for several hours. After this initial 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 of 20°C or lower. 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, either 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 lists some of the constituents of the ripe banana that was used in the process of the invention. For comparison, the levels of the same constituents in unripe bananas are also indicated. The percentages are mass percentages.

[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% (excluding pericarp) 2.7% Starch 2.6% 61.7

[0091] The pH of the puree 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 needs to be called into question.

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

[0094] First embodiment: Formulation of the different mixtures

[0095] The various mixtures prepared and used for sheet / plate formation are grouped in Table 2 below. The % are mass percentages. Water refers to the water added to the puree for mixing with 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] Figure 1 shows various samples of imitation leather according to the invention. They can be seen to have a smooth, uniform, slightly glossy, black surface. (obtained by adding quercetin or activated charcoal).

[0098] Characterization of the materials in plate / sheet form obtained

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

[0100] Measuring the contact angle with a water droplet makes it possible to determine whether the surface of the material is hydrophilic or hydrophobic. 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 was measured using an OCA 15EC contact angle goniometer connected to a computer. Using the SCA20-Software for OCA and PCA software installed on the computer, a 3 ql water droplet was deposited onto the surface of the material, and after a 2-second wait, a photograph of the droplet was taken. The angle was measured on the left and right sides, and then the average was calculated using the formula 0 = (0(left) + 0(right)) / 2. For each material, this operation was repeated 10 times, and the contact angle of the material corresponded to the average of the 10 measurements.

[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 specimen is cut with a punch as specified in ISO 2419.

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

[0110] "Formula 1 F max ,* x £ / O ~ sgj [YES] Formula 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 gap of the jaws of the tensile testing machine in millimeters, and L is the gap, in millimeters, of the jaws after the specimen breaks.

[0113] In total, for each material, 6 test specimens are required, three cut lengthwise and three crosswise. The tensile strength of the material corresponds to the average tensile strength of the 6 specimens.

[0114] Tear resistance

[0115] The tearing of vegetable-based imitation leathers was studied using a SHIMADZU tensile testing machine according to ISO 3377-2. The study consisted of cutting a rectangular specimen, pierced with a hole of specified shape, using a die conforming to the specifications of ISO 2419, and placing it on the upward-facing ends of a pair of specimen holders fixed to the jaws of the tensile testing machine.

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

[0117] In total for each material, 6 test specimens 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 resistance 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] Measurement of the contact angle

[0122] [Tables3] Materials 0(°) with a water droplet 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 strength (N) ISO 3377-2 Standard deviation Tear resistance (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 observed that the final material in the form of a plate / sheet has a thinner profile than the composition layer formed. Nevertheless, all the sheets / plates have a thickness usable in the leather industry.

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

[0128] These results also show that tear resistance depends on the type of fabric on which the composition layer is deposited. Tear resistance tests were carried out on untreated cotton fabric and untreated linen fabric. Linen fabric exhibited a tear resistance 3 times greater than that of cotton fabric.

[0129] The F9 formulation material proves satisfactory in terms of qualitative and quantitative properties. Indeed, it exhibits good texture, a pleasant feel, suppleness, and hand flexibility, making it suitable for use in leather goods, as well as good tensile strength. It is also relatively hydrophobic.

[0130] Tensile strength tests of the material with formulation F9 were carried out. They are grouped in Table 5 below. [Tables 5] Specimen Width (mm) Thickness (mm) ΔR (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 Mean 4.2 1.14 13 4.48

[0131] It is observed that the tensile strength value of the material in formulation F9 is on the order of 13 MPa. This value is similar to that of certain brands of commercial vegetable-based imitation leathers.

[0132] Tensile strength tests of materials F14, 18 and F20 were carried out as indicated for material F9. The results are shown in Table 6 below. [Tableauxô] Materials Thickness (mm) orR (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 observed that the F14 formulation material exhibits the highest tensile strength. However, the F20 material also exhibits sufficient tensile strength to be used in all applications of 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 procedure was used except for one sample for which the drying temperature is explicitly stated. [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 (%) Colorant (%) 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 tests for measuring the contact angle and tear resistance were carried out. The results are summarized in Tables 9 and 10 below. The same protocols were used.

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

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

[0140] Measurement of tear resistance and thickness

[0141] [Tables 10] Material Thickness (mm) Tear Strength (N) ISO 3377-2 Standard Deviation Tear Resistance (N / mm) F25 (French Linen) 1.2 75.5 11.84 63 F25 (Linen) 1.2 46.2 9.16 38.5 F26 (French Linen) 1.3 70.4 7.37 54.1 F27 (Cotton Fabric) 1.3 17.4 2.38 13.4

[0142] Again, it is observed that tear resistance is related to the underlayer textile. It is also observed that the use of sorbitol as a texturizing agent provides lower 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 bends; direction 2 hole at 200000 bends.

[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 Average tensile strength 7.0 N / mm² Longitudinal direction - average elongation under maximum force 29% Transverse direction - average elongation under maximum force 24% Average elongation under maximum force 27% [Tables 12] Dry bending (FlexionBALLY) - ISO 5402-1: 2017 Direction 1 - Dry bending - Number of cycles: 2000 Direction 1 - Dry bending - De- Visible cracks with gradations observed by the eye Direction 2 - Dry bending - Number of cycles: 1000 Direction 1 - Dry bending - De- Visible cracks with gradations observed by the eye [Tables 13] Dry Martindale abrasion resistance on uppers, linings, and insoles - EN 13520:2001 / Al:2004 Applied pressure: 12 kPa Abrasive: Abrasive combed wool Number of cycles to first degradation: 10,000 Number of cycles to first hole: >256,000 Total number of cycles: 25,600 Final observations: 1st degradation: partial abrasion of the specimen. / / at 25,600 cycles: slight abrasion of the material, black over the entire specimen. No hole [Tables 14] Tear resistance - 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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