Composite material containing coffee grounds and suitable for contact with a food product – process and associated products

Abstract

The present invention relates to a composite material comprising between 70% and 98.5% by weight of a thermoplastic polymeric material, between 1% and 29% by weight of coffee grounds, and between 0.5% and 5% by weight of a mixture comprising at least one silicate, a container comprising such a material, and a method of manufacturing such a material.

Description

Title of the invention: Composite material containing coffee grounds and capable of being brought into contact with a food product - process and associated products Technical field

[0001] The present invention relates to the field of composite polymer materials, more specifically to polymer composites reinforced with natural organic fillers and inorganic compounds. This invention falls within the technical field of advanced materials science and engineering, with a particular focus on the development of sustainable and performance-enhanced polymer materials for various industrial applications. The innovative aspect of the invention lies in the integration of coffee grounds, a widely available organic waste, with silicate compounds, which synergistically achieve excellent material properties such as mechanical strength, thermal stability and suitability for contact with food.The resulting composite materials are particularly relevant to industries seeking environmentally friendly alternatives to conventional fillers used in polymer matrices, including, but not limited to, the packaging, construction, automotive, and consumer goods sectors.

[0002] The present invention relates, in particular, to a composite material containing coffee grounds and capable of being brought into contact with a food product, a method and associated products, in particular a container such as a coffee cup. Technological background

[0003] A by-product of coffee preparation, several million tons of coffee grounds are generated annually worldwide. It is increasingly recognized for its many potential uses, particularly in terms of recycling and environmental impact.

[0004] Rich in organic compounds, including cellulose, lignin, and various acids and oils, coffee grounds also contain nutrients such as nitrogen, phosphorus, and potassium.

[0005] Coffee grounds are often thrown away with household waste and end up in landfills, where they decompose and can produce methane, a greenhouse gas. Recycling and reusing them can therefore help reduce the amount of waste sent to landfills and its harmful impact on the environment.

[0006] One of the difficulties in using coffee grounds in the production of materials for use in the food industry, and in particular materials in direct contact with solid or liquid foods, hot or cold, is to avoid or reduce as much as possible the unpleasant taste and / or smell associated with the use of coffee grounds while ensuring that the compounds contained in the coffee grounds, such as caffeine, acids or certain minerals, are not (or only slightly, within certain thresholds) extracted into the food. A number of standards and regulations for materials that come into contact with food are in force in France, Europe and most countries around the world, and must be respected.

[0007] Another of these difficulties is to obtain a composite material containing coffee grounds in a significant quantity while retaining mechanical properties identical or sufficiently close to the material free of coffee grounds, to allow its use in the desired applications, such as in particular, in the manufacture of cups or coffee mugs.

[0008] For example, document US 2022 / 0325104 A1 describes a composite material comprising coffee grounds particles having a size of 0.3 mm to 1 mm and at least one polymer chosen from aqueous acrylic emulsions, aqueous acrylic emulsions and styrene-acrylic copolymer emulsions.

[0009] GB 2567532 A describes a high-temperature resistant cup made entirely of biodegradable bioplastic containing up to 60% coffee residue. The bioplastic is described as not only keeping liquids warm but also providing a pleasant feel to the touch, without being too hot.

[0010] Document CN 110172258 A describes a composite material based on polyolefin and coffee grounds and a method for its preparation. This document highlights the difficulties related to the difference in polarity between coffee grounds and polyolefin plastic posing challenges in terms of compatibility and mechanical properties. To solve these problems, the patent application proposes a formulation comprising a mixture of 35 to 45% polyolefin, 45 to 55% coffee grounds, and 5 to 10% of an ionic polymer compatibilizer, of the ethylene-methacrylic acid copolymer type. Summary of the invention

[0011] An object of the present invention is to solve at least one of the drawbacks of the technological background.

[0012] The present invention relates to a novel composite material comprising a polymer matrix integrated with coffee grounds and at least one type of silicate compound. This invention addresses and solves specific challenges associated with existing composite polymers using organic fillers by introducing an inorganic silicate component to improve, or at least maintain, the characteristics material performance.

[0013] Key aspects of the invention include:

[0014] A composite material where the polymer matrix is ​​uniformly mixed with treated coffee grounds and silicate compounds, resulting in a homogeneous distribution of both types of fillers in the matrix.

[0015] The coffee grounds are treated to optimize their compatibility and adhesion with the polymer matrix and silicate compounds, thereby improving the overall structural integrity of the composite.

[0016] The silicate compounds are selected based on their ability to strengthen or maintain the mechanical strength, thermal stability, resistance to environmental degradation of the polymer matrix, and to allow the use of the composite in the manufacture of products intended to be placed in contact with food, in conjunction with coffee grounds.

[0017] The invention provides methods for preparing the composite material, including steps for treating coffee grounds, selecting appropriate silicate compounds and process conditions for incorporating them into the polymer matrix.

[0018] The resulting composite material exhibits improved, or at least equivalent, mechanical properties, such as tensile strength, compressive strength, fracture toughness, and impact resistance, superior to, or as good as, those of conventional polymers.

[0019] In addition, the composite material demonstrates very good thermal properties, including excellent heat resistance, making it suitable for a wider range of applications.

[0020] The invention also encompasses the use of the composite material in various products and industries, providing an environmentally friendly alternative to traditional polymer composites.

[0021] The specific ratio of coffee grounds to silicate compound(s) in the polymer matrix is ​​optimized to achieve the desired properties for the intended applications, allowing versatility in the use of the material.

[0022] The objectives of the present invention are to provide a polymer composite material that utilizes waste efficiently and functionally, to improve or maintain the physical properties of polymer composites while making them suitable for use in applications involving food contact, by incorporating silicate compounds, and to develop a material that is both environmentally friendly and has good performance compared to existing alternatives.

[0023] In achieving these objectives, the invention presents a composite material which is not only robust and versatile in its application, but also contributes posi tively to environmental sustainability by reusing organic waste. This dual focus on performance and ecology represents a significant advance in composite materials technology.

[0024] The advantages of the invention extend to ease of manufacture and potential for application in a wide range of industries where polymeric materials are used. The inventive composite is particularly advantageous in food fields where material properties and environmental impact are of concern, such as in the disposable food container industry.

[0025] In particular, one of the advantages of the present invention is that it makes it possible, by replacing the virgin raw material of the thermoplastic polymeric material with coffee residues, to contribute to the reduction of waste and the protection of the environment by avoiding its decomposition and the emission of greenhouse gases.

[0026] Another advantage of the composite material of the present invention is to take advantage of coffee grounds waste by integrating them into a thermoplastic polymeric material to create a composite with multiple advantages, such as durability, aesthetic appearance, recyclability, corrosion resistance, and others.

[0027] Another advantage of the composite material of the present invention is that it allows the production of materials containing coffee grounds which can be used in the food industry, and in particular materials in direct contact with solid or liquid, hot or cold foods.

[0028] Another advantage of the composite material of the present invention is that it allows the production of materials containing coffee grounds and having little or no taste and / or olfactory unpleasantness linked to the use of coffee grounds.

[0029] Another advantage of the composite material of the present invention is that it allows the production of materials containing coffee grounds whose constituents, such as caffeine, acids or other minerals, do not migrate (or only slightly) into the foods with which it is in contact.

[0030] Another advantage of the composite material of the present invention is that it allows the production of materials containing coffee grounds which comply with the standards and regulations for materials which come into contact with food such as those in force in France, Europe and most countries in the world.

[0031] Another advantage of the composite material of the present invention is that it allows the production of materials containing coffee grounds allowing the manufacture of containers or receptacles, which can in particular accommodate solid or liquid foodstuffs, washable by hand or in the dishwasher, and thus allow their reuse.

[0032] Another advantage of the composite material of the present invention is to allow the production of materials containing coffee grounds allowing the manufacture of containers or receptacles, which can in particular accommodate solid or liquid foods, compatible with microwave use.

[0033] Another advantage of the composite material of the present invention is to allow the production of materials containing coffee grounds having identical, or almost identical, mechanical properties, or even sufficiently close to the virgin material free of coffee grounds, to allow its use in the desired applications, such as in particular, in the manufacture of coffee cups or mugs.

[0034] Another advantage of the composite material of the present invention is to allow the production of materials containing coffee grounds having at least one or more of the aforementioned advantages.

[0035] Accordingly, according to a first aspect, the present invention relates to a composite material comprising between 70% and 98.5% by weight of a thermoplastic polymeric material, between 1% and 29% by weight of coffee grounds, and between 0.5% and 5% by weight of a mixture comprising at least one silicate.

[0036] Advantageously, the silicate is a phyllosilicate, in particular a clay compound or talc, in particular the silicate is chosen from bentonite, kaolin or kaolinite, montmorillonite, illite, talc, or any of their combinations.

[0037] Advantageously, said thermoplastic polymeric material is chosen from polyolefins, polyesters, polystyrenes or any of their mixtures, in particular, chosen from polyolefins, polyesters, or any of their mixtures, in particular again, said thermoplastic polymeric material is a polyolefin or a mixture of polyolefins, in particular, a polyethylene or a polypropylene or a mixture of a polyethylene and a polypropylene.

[0038] Advantageously, said thermoplastic polymeric material is a polyethylene or a polypropylene.

[0039] The polyethylene, as may be used in the present invention, is selected from low density polyethylene (LDPE or LDPE), high density polyethylene (HDPE or HDPE), or linear low density polyethylene (LLDPE or LLDPE).

[0040] The polyester, as may be used in the present invention, is advantageously polylactic acid or PLA.

[0041] Advantageously, the thermoplastic polymeric material is biosourced and / or biodegradable.

[0042] Advantageously, said thermoplastic polymeric material is a biosourced and / or biodegradable polyethylene, polypropylene, or polylactic acid, or any of their mixtures.

[0043] Advantageously, said composite material additionally comprises carbon black.

[0044] The relative proportions of the compounds in the silicate mixture according to the invention are not particularly limited and may be present in varying proportions. In particular, when clay, talc and carbon black comprise the silicate mixture, the clay is present between 20% and 60%, the talc between 10% and 50% and the carbon black between 2% and 20% by weight relative to the total weight of the silicate mixture. In particular again, when bentonite, kaolinite, talc and carbon black comprise the silicate mixture, the bentonite is present between 10% and 30%, the kaolinite is present between 10% and 30%, the talc between 10% and 50% and the carbon black between 2% and 20% by weight relative to the total weight of the silicate mixture.

[0045] According to one embodiment, said coffee grounds are dried before the grinding step to achieve a residual moisture content of less than 50%, in particular less than 30%, and in particular still less than 20%. Drying can be obtained by various methods known to those skilled in the art, and in particular by steaming.

[0046] Advantageously, said coffee grounds are ground, in particular after drying, and comprise particles of a size essentially less than 500 pm (micron). In particular, more than 90% (between 90% and 100%) of the coffee grounds particles have a size of between 100 pm (micron) and 500 pm (micron) and / or more than 50% (between 50% and 100%) of the coffee grounds particles have a size of between 250 pm (micron) and 500 pm (micron) and / or less than 10% (between 0% and 10%) of the coffee grounds particles have a size of less than 100 pm (micron).

[0047] According to a second aspect, the present invention relates to a container or receptacle comprising a composite material according to the present invention.

[0048] Advantageously, said container or receptacle is obtained by a conventional injection process, optionally preceded by drying of the granules by placing the granules in an oven or any other method.

[0049] Said container or receptacle may be single-use or reusable, in particular reusable.

[0050] Advantageously, said container or receptacle can be cleaned in a dishwasher.

[0051] Advantageously, said container or receptacle is compatible with use in a microwave and is therefore capable of containing a food product that can be reheated using a microwave.

[0052] According to a third aspect, the present invention relates to a method for manufacturing a composite material comprising a succession of steps, in particular, drying, grinding, in particular by micronization, mixing, and optionally, extrusion, and granulation.

[0053] The term "approximately", as used in this patent application, refers to a tolerance range or degree of accuracy associated with a numerical value. This range is generally within an interval of plus or minus 10%, in particular plus or minus 5%, and in particular still, plus or minus 1% of the stated value, unless a different range is explicitly specified. This definition is generally intended to encompass slight variations that may be encountered under practical implementation or measurement conditions, while preserving the integrity and clarity of the patent claims. Detailed description

[0054] An object of the present invention is to solve at least one of the drawbacks of the technological background.

[0055] According to a first aspect, the present invention relates to a composite material comprising between 70% and 98.5% by weight of a thermoplastic polymeric material, between 1% and 29% by weight of coffee grounds, and between 0.5% and 5% by weight of a mixture comprising at least one silicate. Advantageously, the present invention comprises between 70% and 98% by weight of a thermoplastic polymeric material, between 1% and 29% by weight of coffee grounds, and between 1% and 5% by weight of a mixture comprising at least one silicate. Particularly, the present invention comprises between 70% and 80% by weight of a thermoplastic polymeric material, between 19% and 29% by weight of coffee grounds, and between 1% and 5% by weight of a mixture comprising at least one silicate.More particularly, the present invention comprises about 74%, in particular 74%, by weight of a thermoplastic polymeric material, about 25%, in particular 25%, by weight of coffee grounds, and about 1%, in particular 1%, by weight of a mixture comprising at least one silicate.

[0056] The term "coffee grounds" or "used coffee residue" refers to ground coffee beans after they have been used to make coffee. Thus, used coffee residue may also be referred to, where appropriate, as "recycled coffee residue" or "waste coffee residue".

[0057] The composition of coffee grounds varies slightly depending on the type of coffee, the preparation method and the degree of roasting, which has no impact on the present invention. However, in general, the main components of coffee grounds are cellulosic fibers, mainly in the form of cellulose and other non-digestible polysaccharides, proteins, lipids, phenols and phenolic acids such as chlorogenic acid, caffeine, minerals such as potassium, magnesium, and phosphorus, melanoidins, dextrins, trigonelline and other organic acids such as citric acid, malic acid and acetic acid which may be present in small amounts.

[0058] Advantageously, the silicate is a phyllosilicate, in particular a clay compound, or talc, in particular the silicate is chosen from bentonite, kaolin or kaolinite, montmorillonite, illite, talc, or any of their combinations.

[0059] Particularly, said composite material comprises between 70% and 98.5% by weight of a thermoplastic polymeric material (in particular 70%-80%), between 1% and 29% by weight of coffee grounds (in particular 19%-29%), and between 0.5% and 5% by weight of a mixture (in particular 1%-5%) comprising at least one, in particular at least two, clay compounds, such as bentonite or kaolin, and talc. Even more particularly, said composite material comprises between 70% and 98.5% by weight of a thermoplastic polymeric material (in particular 70%-80%), between 1% and 29% by weight of coffee grounds (in particular 19%-29%), and between 0.5% and 5% by weight of a mixture (in particular 1%-5%) comprising bentonite, kaolin (or kaolinite), and talc.

[0060] According to the present invention, the term “clay compound” means a compound comprising at least one clay, designating a group of natural, fine, water-soluble earth minerals, composed mainly of hydrated aluminum silicates with the potential presence of other cations such as magnesium, sodium, potassium, and calcium. Types of clay include, but are not limited to, bentonite, kaolinite, montmorillonite, illite, and other clay minerals. The composition of the clay may be modified or optimized by chemical or thermal treatments to improve its properties or make it suitable for specific applications that may be described within the scope of the invention.

[0061] Talc, as used in the present invention, refers to a naturally occurring hydrated magnesium silicate having the chemical formula Mg3Si4O10(OH)2. This mineral substance is characterized by its lamellar or flaky nature, its softness (being the softest mineral on the Mohs scale). In the context of the present invention, talc may be used in various forms, including but not limited to micronized powders, or granules.

[0062] A thermoplastic polymeric material, according to the present invention, refers to a material comprising one or more long molecular chain polymers that exhibit a reversible transition between the solid state and the fluid state under the effect of heat. These polymers are characterized by repeating units of monomers and / or co-monomers that may be linear, branched or networked, without inter-chain covalent bonds, thus allowing repeated melting and molding of the material. The solidification process does not result from irreversible chemical crosslinking but from the cooling and partial recrystallization of the polymer chains, thus allowing the material to retain its initial physical properties without significant degradation. This property is, in general, exploited in applications requiring manufacturing processes such as injection, extrusion, blow molding or thermoforming.The composition may also include various additives to optimize properties such as thermal stability, mechanical strength, . conductivity, color and compatibility with other materials.

[0063] Advantageously, said thermoplastic polymeric material is chosen from polyolefins, polyesters, polystyrenes or any of their mixtures, in particular, chosen from polyolefins, polyesters, or any of their mixtures, in particular again, said thermoplastic polymeric material is a polyolefin or a mixture of polyolefins, in particular, a polyethylene or a polypropylene or a mixture of a polyethylene and a polypropylene.

[0064] Polyethylene (PE), as used in the context of the present invention, refers to a thermoplastic polymer consisting of long repeating chains of ethylene units (CH2=CH2), resulting from the polymerization of ethylene. It can be classified into different categories based on its density and molecular structure, including low-density polyethylene (LDPE), high-density polyethylene (HDPE), and linear low-density polyethylene (LLDPE).

[0065] Polypropylene (PP), according to the present invention, refers to a thermoplastic polymer obtained by the polymerization of propylene (or propene, CH3CH=CH2). Polypropylene can be in different forms, such as polypropylene homopolymer, polypropylene block copolymer, and polypropylene random copolymer, each offering distinct properties in terms of rigidity, clarity, impact resistance, and heat treatment.

[0066] Polyesters, as defined in the context of the present invention, are a category of polymers obtained by the polycondensation reaction between carboxylic acids (or their derivatives, such as anhydrides or esters) and polyhydric alcohols. This family of polymers is characterized by the repetition of ester units in their main chain. Common examples of polyesters include polylactic acid or PLA.

[0067] Polylactic acid (PLA), as used herein, refers to a biodegradable thermoplastic aliphatic polymer synthesized from lactic acid, a monomer derived from renewable sources such as corn starch, sugarcane, or other biomasses. PLA is characterized by its composition of stereoregular polymer chains, which can vary between atactic, isotactic, and syndiotactic, depending on the synthesis method and catalysts used. The polymer can have various forms, including but not limited to, homopolymers, copolymers, blends, and composites, and can be modified with various additives to improve properties such as clarity, impact resistance, biodegradability rate, and heat resistance.

[0068] Polystyrene (PS), as used in the context of the present invention, refers to a thermoplastic polymer synthesized by the polymerization of styrene (ethenylbenzene) monomer. This polymer is characterized by its transparency, rigidity, and ease of molding and processing. It exists in various forms, including, but not limited to, crystal polystyrene (PS), high-impact or impact-resistant polystyrene (HIPS), and expanded polystyrene (EPS). Each of these variants has unique properties in terms of mechanical strength, density, impact behavior, and thermal insulation. Polystyrene can be modified with additives, colorants, reinforcing agents, or other polymers to improve specific properties such as UV resistance, fire resistance, solvent resistance, or to obtain special characteristics that may be useful for applications related to the present invention.

[0069] Advantageously, said thermoplastic polymeric material is a polyethylene or a polypropylene.

[0070] The polyethylene, as may be used in the present invention, is selected from low density polyethylene (LDPE or LDPE), high density polyethylene (HDPE or HDPE), or linear low density polyethylene (LLDPE or LLDPE).

[0071] The polyester, as may be used in the present invention, is advantageously polylactic acid or PLA.

[0072] Advantageously, the thermoplastic polymeric material is biosourced and / or biodegradable. PE, PP or PLA will be preferred in this particular case.

[0073] Bio-based polymers, as defined in the present invention, refer to thermoplastic polymers wholly or partially derived from renewable resources, instead of traditional petrochemical sources. These materials are obtained by the polymerization of one or more monomers (such as, for example, ethylene, propylene, or PLA), where the monomer(s) are produced from biological feedstocks such as sugarcane, grains, vegetable oils, or biomass. Bio-based polymers may have the same chemical and physical characteristics as their conventional counterparts, including the same chemical formula, but are distinguished by their bio-based origin. This material can be used in various applications where the conventional polymer in question is used, such as packaging, household products, automotive components, and agricultural films.

[0074] Advantageously, said thermoplastic polymeric material is a biosourced polyethylene, a biosourced polypropylene or a biosourced polylactic acid.

[0075] A biodegradable polymer, according to the present invention, refers to a polymer that can decompose into natural elements such as water, carbon dioxide, and biomass, under the action of microorganisms such as bacteria, fungi, and algae. This decomposition must occur under specific environmental conditions, such as industrial composting or soil, within a period of time reasonable. Biodegradable polymers can be either synthetic or natural, and are characterized by their molecular structure which allows for easy and complete degradation.

[0076] Advantageously, said thermoplastic polymeric material is a biosourced and / or biodegradable polyethylene, polypropylene, or polylactic acid, or any of their mixtures.

[0077] PLA is, for example, a biodegradable polymer, and it will therefore be particularly advantageous to use it for applications requiring or involving the need to use a biodegradable and biosourced polymeric material.

[0078] Advantageously, said composite material additionally comprises carbon black.

[0079] Carbon black, as described in the present invention, refers to a finely divided amorphous form of carbon obtained by the partial combustion or thermal decomposition of fossil or natural hydrocarbons. This material is characterized by its high specific surface area, its particulate structure in the form of spheres or aggregates of spheres, and its intense black color.

[0080] In particular, said composite material comprises between 70% and 98.5% by weight of a thermoplastic polymeric material, such as PE, PP, PLA or one of their mixtures, in particular bio-sourced PE or PP, between 1% and 29% by weight of coffee grounds, and between 0.5% and 5% by weight of a mixture comprising at least one, in particular at least two, and in particular still at least three, compounds chosen from a clay, such as bentonite and / or kaolin (kaolinite), talc and carbon black. Even more particularly, said composite material comprises between 70% and 98.5% by weight of a thermoplastic polymeric material, such as PE, PP, PLA or one of their mixtures, in particular bio-sourced PE or PP, between 1% and 29% by weight of coffee grounds, and between 0.5% and 5% by weight of a mixture comprising bentonite, kaolin (or kaolinite), and talc.

[0081] Advantageously, said composite material comprises between 70% and 80% by weight of a thermoplastic polymeric material, such as PE, PP, PLA or one of their mixtures, in particular bio-sourced PE or PP, between 19% and 29% by weight of coffee grounds, and between 1% and 5% by weight of a mixture comprising at least one, in particular at least two, in particular still at least three, and more particularly all four, compounds chosen from a clay, such as bentonite and / or kaolin (kaolinite), talc and carbon black.

[0082] The relative proportions of the compounds in the silicate mixture according to the invention are not particularly limited and may be present in equal proportions by weight. In particular, when clay, talc and carbon black make up the silicate mixture, the clay is present between 20% and 60%, the talc between 10% and 50% and carbon black between 2% and 20% by weight relative to the total weight of silicate mixture. In particular again, when bentonite, kaolinite, talc and carbon black compose the silicate mixture, bentonite is present between 10% and 30%, kaolinite is present between 10% and 30%, talc between 10% and 50% and carbon black between 2% and 20% by weight relative to the total weight of silicate mixture.

[0083] Advantageously, said coffee grounds are ground, in particular after drying, and comprise particles of a size essentially less than 500 pm (micron). In particular, more than 90% (between 90% and 100%) of the coffee grounds particles have a size of between 100 pm (micron) and 500 pm (micron) and / or more than 50% (between 50% and 100%) of the coffee grounds particles have a size of between 250 pm (micron) and 500 pm (micron) and / or less than 10% (between 0% and 10%) of the coffee grounds particles have a size of less than 100 pm (micron). In particular, between 0% and 10% of the coffee grounds particles have a size less than 100 pm (micron), between 35% and 45% of the coffee grounds particles have a size between 100 pm (micron) and 250 pm (micron), and between 45% and 55% of the coffee grounds particles have a size between 250 pm (micron) and 500 pm (micron).In particular again, between 6% and 7% (in particular about 6.7%) of the coffee grounds particles have a size of less than 100 pm (micron), between 41% and 42% (in particular about 41.8%) of the coffee grounds particles have a size of between 100 pm (micron) and 250 pm (micron), and between 51% and 52% (in particular about 51.5%) of the coffee grounds particles have a size of between 250 pm (micron) and 500 pm (micron).

[0084] It has been discovered, quite surprisingly, that the technical characteristics, in particular mechanical and thermal characteristics, of the composite material obtained according to the invention are particularly good.

[0085] For example, the composite material according to the invention has a tensile modulus greater than 500 MPa, in particular greater than 700 MPa, and in particular still greater than 900 MPa, as measured by common standard methods such as governed by standards ASTM D638, ISO 527-1, or ASTM D3039, in particular standard ISO 527-1 or similar. According to a particular embodiment of the invention, said composite material has a tensile modulus of between 800 MPa and 1000 MPa.

[0086] For example, the composite material according to the invention has a threshold stress greater than 10 MPa, in particular greater than 15 MPa, and in particular still greater than 20 MPa, as measured by common standard methods such as governed by standards ASTM D638, ISO 527-1, or ASTM D3039, in particular standard ISO 527-1 or similar. According to a particular embodiment of the invention, said composite material has a threshold stress of between 15 MPa and 25 MPa.

[0087] For example, the composite material according to the invention has a stress at the rupture greater than 10 MPa, and in particular greater than 15 MPa, as measured by common standard methods such as governed by standards ASTM D638, ISO 527-1, or ASTM D3039, in particular standard ISO 527-1 or similar. According to a particular embodiment of the invention, said composite material has a breaking stress of between 15 MPa and 25 MPa.

[0088] For example, the composite material according to the invention has an elongation at break greater than 10 MPa, and in particular greater than 15 MPa, as measured by common standard methods such as those governed by standards ASTM D638, ISO 527-1, or ASTM D3039, in particular standard ISO 527-1 or similar. According to a particular embodiment of the invention, said composite material has an elongation at break of between 15 MPa and 25 MPa.

[0089] For example, the composite material according to the invention has a 2J notched Charpy impact test toughness greater than 1 kJ / m2, and in particular approximately 3 kJ / m2, as measured by the standard method ISO 179-1 / lfU or similar.

[0090] For example, the composite material according to the invention has a resistance to hot deformation (0.45 MPa) greater than 50°C, and in particular greater than 70°C, as measured by the current standard methods ISO 75-2 / B or similar. According to a particular embodiment of the invention, said composite material has a resistance to hot deformation of between 50 MPa and 100 MPa.

[0091] For example, the composite material according to the invention has a Vicat point (temperature at which the material softens) greater than 80°C, in particular greater than 100°C, and in particular still greater than 120°C, as measured by the current standard methods ISO 306 / A or similar. According to a particular embodiment of the invention, said composite material has a Vicat point of between 80°C and 150°C MPa.

[0092] These mechanical and thermal properties are important, in particular when the composite material of the invention is used in applications where the material is in contact with hot products such as hot liquids, and in particular, hot coffee whose temperature is often around 100°C.

[0093] The composite material of the invention may also be compatible with food contact and may therefore be used in the manufacture of coffee cups or tumblers. To this end, it has been discovered, quite surprisingly, that the composite material of the invention complies with the requirements of the global and specific migration standards, in particular, of Commission Regulation (EU) No 10 / 2011 of 14 January 2011 and its amendments, as well as with the requirements of the standards on suitability for food contact, in particular, of Regulation (EC) 1935 / 2004 Article 3, Decree 2007 / 766.

[0094] In particular, the composite material of the invention allows contact with cold foods, particularly hot foods, which can be consumed by a consumer without risk to their health, and in particular, due to the non- or low migration of phthalates and / or metals from the material to the food in contact.

[0095] Equally surprisingly, the authors discovered that the specific composition of the composite material of the invention was entirely suitable for the manufacture of products requiring contact with food intended to be consumed by a human being. In particular, the composite material of the invention does not modify or only slightly modifies the taste and / or the smell of the food with which it is in contact.

[0096] According to a second aspect, the present invention relates to a container or receptacle comprising a composite material according to the present invention.

[0097] In particular, the container or receptacle is a cup or mug, whatever its shape, for single use or reusable, capable of receiving a solid or liquid food product, in particular liquid, hot or cold, in particular hot. In particular, said food product is coffee or hot water.

[0098] The cup may be of any shape suitable for holding liquids. For example, the cup may be handleless, or may include a handle. Preferably, the cup may be a cylindrical or frusto-conical cup without a handle.

[0099] The composite material may advantageously have low thermal conductivity, so that the hot contents within the container remain hot, and the cup is not too hot to the touch when containing hot liquids.

[0100] Advantageously, said container or receptacle is obtained by mixing a thermoplastic polymeric material, used coffee grounds and at least one silicate to form a mixture; and by extruding the mixture to form rods or rods. Said rods are then transformed into composite granules suitable for injection molding or blow molding, in particular by injection.

[0101] The mixture may be granulated using conventional twin-screw extrusion equipment to obtain the plastic pellets. The plastic pellets may also contain other polymer processing additives such as pigments, UV antioxidants, lubricants and reinforcers if necessary.

[0102] Said container or receptacle may be single-use or reusable, in particular reusable. Advantageously, to be reused under good hygienic conditions, the container or receptacle must be able to be cleaned without this causing deformation, wear, deterioration or significant damage preventing its reuse by the same user or a different user. In particular, said container or receptacle is therefore compatible with washing in water, with or without detergent, hot or cold. Advantageously again, said container or receptacle is dishwasher-safe. It is therefore compatible with a cleaning treatment involving the use of a detergent, hot water, in particular hot water at a temperature temperature above 40°C, in particular still between 40°C and 70°C, for a period of at least 5 minutes, in particular at least 10 minutes and in particular still at least 20 minutes.

[0103] Advantageously, said container or receptacle is capable of containing a food product which can be reheated using a microwave.

[0104] Advantageously, the container can withstand temperatures of at least 100°C, or at least 120°C, or at least 150°C without deforming.

[0105] According to a third aspect, the present invention relates to a method for manufacturing a composite material comprising a succession of steps, in particular, drying, grinding, in particular by micronization, mixing, and optionally, extrusion, and granulation.

[0106] According to a third aspect, the present invention relates to a method of manufacturing a composite material comprising the steps of: - Grinding coffee grounds, in particular, grinding coffee grounds into coffee grounds powder with a particle size as described in the present application, essentially less than 500 pm (micron), in a grinder; - Optionally, drying the coffee grounds, in particular, placing the ground coffee grounds powder in a dryer, and drying for 2 to 4 hours at a temperature of 50 to 100°C to ensure that the water content of the coffee grounds powder is less than 50%, in particular less than 30%, and in particular still less than 20%; - compounding of the raw materials, in particular, bringing into contact, in particular mixing, the polymer matrix, the coffee grounds and at least one type of silicate compound, all as described in the present application, at a temperature between 150°C and 250°.

[0107] Optionally, the method comprises an additional step of extruding the compounded material, in particular in the form of a rod or rod, and / or followed by a granulation step.

[0108] According to a certain embodiment, the compounding, extrusion and granulation steps can be carried out “one pot”, that is to say using the same equipment, in particular a granulator.

[0109] Optionally, the method comprises an additional step of drying the compounded composite material at a temperature between 50°C and 100°C, in particular 70°C and 100°C, and in particular still approximately 80°C, for a period of at least 30 minutes, in particular at least 1 hour, in particular still at least 2 hours.

[0110] Optionally, the method may comprise an additional molding step, in particular, in which the composite material, typically in the form of granules, is placed in a molding machine for extrusion or injection molding, in particular injection molding. This additional molding step may be preceded by an additional step of drying the granules, in particular, at a temperature between 50°C and 100°C, in particular 70°C and 100°C, and in particular still about 90°C, for a period of at least 30 minutes, in particular at least 1 hour, in particular still at least 2 hours, and particularly 3 hours or more.

[0111] In the context of the invention, the injection step can be carried out by any type of apparatus provided for this purpose. In particular, the injection molding machine is an injection-molding machine having a barrel in which the composite material is placed. The temperature of this barrel can be set to a temperature between 150°C and 250°C, and in particular to approximately 200°C. The temperature at which the injection is carried out is between 150°C and 250°C, in particular 150°C and 200°C, and in particular still approximately 195°C.

[0112] At the end of the injection, the molds are cooled and the parts, objects, containers or receptacles produced are removed from the mold.

[0113] The measurement of the humidity level can be carried out by various methods and devices. These methods vary in accuracy, cost and complexity. Within the scope of the invention, oven drying, Karl Fischer, desiccant, spectroscopic, hydrometric balance, or distillation methods can be considered.

[0114] According to a certain embodiment, the humidity level after grinding is lower than that before grinding and is advantageously lower than 10% after grinding, in particular approximately 6%.

[0115] In the context of the invention, the compounding step can be carried out by any type of equipment provided for this purpose, in particular, a high-speed mixer, an extruder (single-screw or twin-screw), a ball mixer, a ribbon or paddle mixer, a vacuum mixer, or a calender. The temperature at which the compounding is carried out generally depends on the thermal properties of the constituents of the mixture subjected to compounding. It is generally between 150°C and 250°C, in particular 180°C and 250°C, and in particular still between 200°C and 250°C. Lower temperatures will be used, for example, when the polymeric material is PLA (generally between 170°C and 190°C) compared to polypropylene (typically between 200°C and 250°C).

[0116] In the context of the invention, the extrusion flow rate is typically less than 15 kg / h (kilogram of composite material compounded per hour), in particular between 5 kg / h and 15 kg / h, in particular still approximately 100 kg / h. Description of examples of implementation

[0117] A composite material and a method according to the invention will now be described. in the following. These examples are not intended to limit the present invention but simply to illustrate the invention as defined in the claims.

[0118] Protocols for producing a composite material according to the invention and manufacturing cups from said material

[0119] The coffee grounds came from the company Expresseau in France. No pre-grinding was carried out. The tests were carried out on a quantity of 5 kg. The inlet humidity level was: 65% RH.

[0120] Drying: The coffee grounds were dried and steamed conventionally at 80°C for 3 hours in a conventional oven / dryer. The outlet moisture content was approximately 15% (15.67%) RH.

[0121] Micronization: The coffee grounds thus dried were micronized using a knife mill as described in French patent application FR3110478A1. The residual moisture content obtained after micronization was approximately 6% (6.07%) RH.

[0122] The particle size profile obtained following grinding was as follows:

[0123] 0-100 pm (micron): 6.7%

[0124] 100-250 pm (micron): 41.8%

[0125] 250-500 pm (micron): 51.5%

[0126] Extrusion: 74% BIO polyethylene (PE) (braskem food contact) was pre-mixed with 25% micronized coffee grounds and 1% of a mixture of bentonite / kaolinite / talc / carbon black reed.

[0127] The extrusion is carried out at a flow rate of 10 kg / h using a twin-screw extruder as described in French patent application FR3110478A1. The compounded material was then dried for 2 hours at 80°C under the same conditions as previously used.

[0128] Injection: The cups were prepared by applying the following different steps:

[0129] - Stoving the pellets

[0130] - Placing the pellets in the sheath

[0131] - Manual injection of test pieces

[0132] - Demolding of the part obtained (test piece for mechanical tests).

[0133] Relative humidity tests: The compound granules are first dried in an oven at 90°C for 4 hours with the following results:

[0134] Compound before steaming:

[0135] Sample 1: 0.24% Sample 2: 0.17%

[0136] Sample 3: 0.17%

[0137] Average: 0.19%

[0138] Compound after removal from the oven:

[0139] Sample 1: 0.18%

[0140] Sample 2: 0.09%

[0141] Sample 3: 0.12%

[0142] Average: 0.13% Observation

[0143] It is noted that the compound absorbs very little moisture.

[0144] Injection tests: An extruder as described in French patent application FR3110478Al is used with a barrel temperature of 200°C and an injection temperature of 195°C and 80 cups conforming to expectations are obtained.

[0145] Testing of the mechanical and thermal properties of a composite material according to the invention

[0146] [Tables 1] Mechanical properties Tensile modulus (MPa) 956 ISO 527-1 Yield stress (MPa) 21 ISO 527-1 Stress at break (MPa) 19 ISO 527-1 Elongation at break (%) 16 ISO 527-1 Charpy notched impact 2J (kJ / m2) 3 ISO 179-1 / lfU Thermal properties Heat deformation (0.45 Mpa) (°C) 72 ISO 75-2 / B Vicat point (°C) 125 ISO 306 / A Processing conditions Baking (°C) 2-3 h at 50°C Processing temperature (°C) 140-180 Mold temperature (°C) 20-30

[0147] Global and specific migratory and organoleptic tests of coffee cups made from a composite material according to the invention

[0148] Test Results: • Global Migration: Compliant with standards with tests carried out under different conditions (acetic acid 3%, ethanol 20%, etc.). • Sensory Examination: Compliance in odor and taste tests. • Bisphenol A in the Material: Concentration below the limit of detection. • Phthalates in Material: All tested forms of phthalates were below the detection limit.

[0149]

[0150]

[0151]

[0152]

[0153]

[0154]

[0155] • Presence of Metals: Tests showed compliance for the presence of various metals in 20% ethanol and 3% acetic acid. Conclusion : • The sample complies with the current legal requirements of Regulations (EC) No. 1935 / 2004 and (EU) No. 10 / 2011. In particular, the results obtained are as follows: Methods used: [Tables 2] Parameters Methods / Method Overall migration EN 1186 A Organoleptic Test BVL B 80.00-4 A Specific migration preparation EN 13130-1:2004 A Metals EPA 6010C A EPA 6020A A Phthalates in the material Standard Bisphenol A in the material Standard Global Migration: Test condition: 3 x 1 hour at 100°C, surface area / volume: 0.8 dm2 / 70 mL - per filling. [Tables 3] Food simulant Individual values ​​Average value Limit value (1) Conclusion Acetic acid 3% (B) 1.0 mg / dm2 1.3 mg / dm2 <1.0 mg / dm2 <1.1 mg / dm2 10 mg / dm2 Compliant Ethanol 20% (C) 1.2 mg / dm2 <1.0 mg / dm2 <1.0 mg / dm2 <1.1 mg / dm2 10 mg / dm2 Compliant (1) according to Regulation (EU) No 10 / 2011 Sensory examination: Test condition: 1 hour at 100°C, surface area / volume: 2.4 dm2 / 210 mL - per filling. [Tables 4] Sample Odor deviation Taste deviation Intensity Significance Intensity Significance Mineral water 1.5 0.05 2.0 0.05 Limit value [2] max. 2.5 max. 2.5 Conclusion Conforms Conforms (2) according to DIN 10955

[0156] Intensity scale

[0157] 0 = Indistinguishable

[0158] 1 = Perceptible

[0159] 2 = Discernable

[0160] 3 = Light

[0161] 4 = Strong

[0162] Dosage of bisphenol A in a composite material according to the invention:

[0163] Test condition: Immersion of a cut sample (size less than 1 cm) with a mass of 5 g (± 0.05 g). Extraction by 100 ml acetonitrile for 24 h (± 1 h) at 23°C (± 1°C). [Tables 5] Parameters Result Limit of quantification Bisphenol A <0.1 mg / kg 0.1 mg / kg According to the implementation of Law No. 2010-729 of June 30, 2010, amended by Law No. 2012-1442 of December 24, 2012 by the DGCCRF, "the threshold of 2 mg / kg of paper and cardboard, determined according to the conventional analysis method developed and validated by the SCL33, is indicated as a threshold for the presence of bisphenol A corresponding to good manufacturing practices (GMP).

[0164] Dosage of phthalates in a composite material according to the invention:

[0165] [Tableauxô] Parameters Result Limit value (3) Conclusion Bis-(2-ethylhexyl)phthalate (DEHP) < 0.01% / / Butylbenzylphthalate (BBP) < 0.01% / / Di-(2-propylheptyl)phthalate (DPHpP) < 0.01% / / Diallylphthalate (DallP) < 0.01% / / Di-benzylphthalate (DBzP) < 0.01% / / Dicyclohexylphthalate (DCHP) < 0.01% / / Diethylphthalate (DEP) < 0.01% / / Diisobutylphthalate (DIBP) < 0.01% / / Diisodecylphthalate (DIDP) < 0.01% / / Diisoheptylnonylundecylphthalate (DHNUP) < 0.01% / / Di-iso-heptylphthalate (DIHP) < 0.01% / / Diisononyl phthalate (DINP) < 0.01% / / Diisooctylphthalate (DIOP) < 0.01% / / Di-isopentylphthalate (DiPP) < 0.01% / / Dimethoxyethylphthalate (DMEP) < 0.01% / / Dimethylphthalate (DMP) < 0.01% / / Di-n-butylphthalate (DBP) < 0.01% / / Di-n-heptylphthalate (DHpP) < 0.01% / / Di-n-hexylphthalate (DNHP) < 0.01% / / Di-n-octylphthalate (DNOP) < 0.01% / / Di-n-pentylphthalate (DNPP) < 0.01% / / Di-n-propylphthalate (DPrP) < 0.01% / / Diphenylphthalate (DPP) < 0,01% / / n-Pentyl-isopentylphthalat (PIPP) < 0.01% / / Diethyladipate (DEA) < 0.01% / / Dibutyladipate (DBA) < 0.01% / / Diisobutyladipate (DIBA) < 0.01% / / 1,2-Cyclohexane-diisononylester < 0.01% / / , (DINCH) Bis(2-ethylhexyl)adipate (DEHA) < 0.01% / / Bis(2-ethylhexyl)terephthalate < 0.01% / / Sum of phthalates Sum of phthalates < 0.01% Not detectable Compliant (3) according to Regulation (EC) No 552 / 2009.

[0166] Dosage of metals in 20% ethanol in a composite material according to the invention:

[0167] Test condition: 1 hour at 100°C, surface area / volume: 1.6 dm2 / 140 mL - per filling. [Paintings?] Paramètres Résultat Valeur limite (4) Conclusion Baryum (Ba) < 0,01 mg / kg 1 mg / kg Conforme Cobalt (Co) < 0,01 mg / kg 0,05 mg / kg Conforme Cuivre (Cu) < 0,01 mg / kg 5 mg / kg Conforme Fer (Fe) <0,1 mg / kg 48 mg / kg Conforme Lithium (Li) < 0,01 mg / kg 0,6 mg / kg Conforme Manganèse (Mn) < 0,01 mg / kg 0,6 mg / kg Conforme Zinc (Zn) < 0,05 mg / kg 5 mg / kg Conforme Aluminium (Al) <0,1 mg / kg 1 mg / kg Conforme Nickel (Ni) < 0,01 mg / kg 0,02 mg / kg Conforme Antimoine (Sb) < 0,01 mg / kg 0,04 mg / kg Conforme Arsenic (As) < 0,002 mg / kg 0,01 mg / kg Conforme Cadmium (Cd) < 0,001 mg / kg 0,01 mg / kg Conforme Calcium (Ca) < 0,2 mg / kg 60 mg / kg Conforme Chrome (Cr) < 0,01 mg / kg 0,01 mg / kg Conforme Plomb (Pb) < 0,002 mg / kg 0,01 mg / kg Conforme Magnésium (Mg) < 0,2 mg / kg 60 mg / kg Conforme Potassium (K) < 0,2 mg / kg 60 mg / kg Conforme Sodium (Na) 0,36 mg / kg 60 mg / kg Conforme Ammonium (NH4) < 0,5 mg / kg 60 mg / kg Conforme Europium (Eu) < 0,01 mg / kg 0,05 mg / kg Conforme Gadolinium (Gd) < 0,01 mg / kg 0,05 mg / kg Conforme Lanthane (La) < 0,01 mg / kg 0.05 mg / kg Compliant Terbium (Tb) < 0.01 mg / kg 0.05 mg / kg Compliant Mercury (Hg) < 0.0002 mg / kg 0.01 mg / kg Compliant,

[0168]

[0169] (4) according to Regulation (EU) No 10 / 2011. Dosage of metals in 3% acetic acid in a composite material according to the invention: Test condition: 1 hour at 100°C, surface area / volume: 1.6 dm2 / 140 mL - per filling. [Tables 8] Paramètres Résultat Valeur limite (5) Conclusion Baryum (Ba) 0,012 mg / kg 1 mg / kg Conforme Cobalt (Co) < 0,01 mg / kg 0,05 mg / kg Conforme Cuivre (Cu) < 0,01 mg / kg 5 mg / kg Conforme Fer (Fe) <0,1 mg / kg 48 mg / kg Conforme Lithium (Li) < 0,01 mg / kg 0,6 mg / kg Conforme Manganèse (Mn) 0,029 mg / kg 0,6 mg / kg Conforme Zinc (Zn) < 0,05 mg / kg 5 mg / kg Conforme Aluminium (Al) <0,1 mg / kg 1 mg / kg Conforme Nickel (Ni) < 0,01 mg / kg 0,02 mg / kg Conforme Antimoine (Sb) < 0,01 mg / kg 0,04 mg / kg Conforme Arsenic (As) < 0,002 mg / kg 0,01 mg / kg Conforme Cadmium (Cd) < 0,001 mg / kg 0,01 mg / kg Conforme Calcium (Ca) 3,9 mg / kg 60 mg / kg Conforme Chrome (Cr) < 0,01 mg / kg 0,01 mg / kg Conforme Plomb (Pb) < 0,002 mg / kg 0,01 mg / kg Conforme Magnésium (Mg) 0,61 mg / kg 60 mg / kg Conforme Potassium (K) 1,4 mg / kg 60 mg / kg Conforme Sodium (Na) 1,9 mg / kg 60 mg / kg Conforme Ammonium (NH4) < 0,5 mg / kg 60 mg / kg Conforme Europium (Eu) < 0,01 mg / kg 0,05 mg / kg Conforme Gadolinium (Gd) < 0,01 mg / kg 0,05 mg / kg Conforme Lanthane (La) < 0,01 mg / kg 0,05 mg / kg Conforme Terbium (Tb) < 0,01 mg / kg 0,05 mg / kg Conforme Mercure (Hg) < 0,0002 mg / kg 0,01 mg / kg Conforme (5) selon le règlement (UE) N° 10 / 2011.

Claims

Claims

1. Composite material comprising between 70% and 98.5% by weight of a thermoplastic polymeric material, between 1% and 29% by weight of coffee grounds, and between 0.5% and 5% by weight of a mixture comprising at least one silicate.

2. A composite material according to claim 1, wherein said silicate is a phyllosilicate, preferably a clay compound or talc.

3. A composite material according to claim 1 or 2, wherein said silicate is selected from bentonite, kaolin or kaolinite, montmorillonite, illite, talc, or any combination thereof.

4. A composite material according to any preceding claim, wherein said thermoplastic polymeric material is selected from polyolefins, polyesters, polystyrenes, or any mixture thereof.

5. A composite material according to any preceding claim, wherein said thermoplastic polymeric material is selected from polyethylene, polypropylene, polylactic acid or any mixture thereof.

6. A composite material according to any preceding claim, wherein said composite material further comprises carbon black.

7. A composite material according to any preceding claim, wherein the relative proportions of the compounds in the silicate mixture by weight are clay between 20% and 60%, talc between 10% and 50% and carbon black between 2% and 20% by weight relative to the total weight of silicate mixture.

8. A composite material according to any preceding claim, wherein said coffee grounds comprise particles substantially less than 500 pm (micron) in size.

9. A container or receptacle comprising a composite material according to any preceding claim.

10. A method of manufacturing a composite material according to any one of the preceding claims, comprising the steps of: - grinding the coffee grounds to obtain a particle size essentially less than 500 pm (micron); - compounding the thermoplastic polymeric material, the coffee grounds and at least one silicate compound, at a tem- temperature between 150°C and 250°.