Non-fluorinated exterior coating based on PES

Abstract

The present invention relates to a coated cooking element (1) for a kitchen item or electrical cooking appliance, comprising a metal substrate (2) coated on at least one face (2a) with a coating (3) intended to form a cooking face free of fluorocarbon resin and coated on at least the other face (2b) with a coating (4) comprising at least the following layers and in this order starting from the metal substrate (2): (4a) primer layer comprising polyethersulfone (PES), (4b) optionally, one or more intermediate layer(s) comprising polyethersulfone (PES) or a mixture of polyethersulfone (PES) and one or more silicone resins, (4c) finishing layer comprising polyethersulfone (PES) or one or more silicone resins or a mixture of polyethersulfone (PES) and one or more silicone resins.

Description

Title of the invention: Non-fluorinated exterior coating based on PES

[0001] The invention applies in the field of exterior coatings for culinary articles or electrical cooking appliances.

[0002] The present invention addresses the technical problem of improving the thermomechanical properties of an outer coating of a culinary item or an electrical cooking appliance. It aims in particular to improve its resistance to abrasion and, where appropriate, its suitability for stamping. DEFINITIONS

[0003] The term "layer" is understood to mean, within the meaning of the present invention, a continuous or discontinuous layer. A continuous layer (or also called a monolithic layer) is a single whole forming a total flat area completely covering the surface on which it is placed. A discontinuous layer (or non-monolithic layer) may comprise several parts, thus not being a single whole.

[0004] The term "base coat", "primer coat", "bonding coat" or "bonding primer" means all the layers from the first layer applied directly to the support (it is preferable that this layer adheres well to the support and provides all its mechanical properties to the coating: hardness, scratch resistance) to the last layer before the first intermediate or decorative layer. The first layer of the coating is a primer layer.

[0005] The term "intermediate layer" means the layers inserted between the primary layer(s) and the finishing layer(s). The intermediate layer(s) may be "decorations" or "decorative layers". The intermediate layer(s) is / are not intended to be in contact with food.

[0006] The term "finishing layer" or "finish" means a continuous surface layer applied after the intermediate layer(s) if the coating comprises one or more intermediate layer(s) or after the primary layer(s). The last layer of the coating is a finishing layer. Usually, at least the last finishing layer, or even all the finishing layers, is / are transparent to allow visibility of the underlying layers, in particular when the underlying layers are decorative layers. The finishing layer(s) protect the underlying layers from mechanical attack and give the coating its non-stick properties. Preferably, in the case of a culinary item or electrical cooking appliance, the last finishing layer is intended to be in contact with food.

[0007] The term "decor" or "decorative layer" means one or more continuous or discontinuous layers comprising a pigment composition. The decor may be in the form of one or more patterns, of one or more colors. A decor is visible to the user clearly with the naked eye and at a normal distance from the kitchen item or electrical cooking appliance.

[0008] The expression "cooking article" should be understood within the meaning of the present invention to mean an object intended for cooking and being heated by an external heating system such as frying pans, saucepans, sauté pans, woks, barbecue grills. A cooking article is capable of transmitting the heat energy provided by this external heating system to a material or food in contact with said object.

[0009] The expression "electric cooking appliance" should be understood within the meaning of the present invention to mean a heating object having its own heating system such as an electric crepe maker, an electric raclette appliance, an electric fondue appliance, an electric grill, an electric griddle, an electric cooker, a bread machine, or an electric pressure cooking appliance.

[0010] The term "coating" means all the layers adhering to the metal substrate and covering this substrate. The coating according to the invention obtained is advantageously solid, "solid" means the characteristic of a cohesive material insoluble in water, in usual solvents, in food components such as aqueous or fatty mixtures, even if the material may have great hardness or great flexibility such as an elastomer.

[0011] In the present invention, the % by weight are expressed in dry weight, i.e. without solvent. Summary of the invention

[0012] A first subject of the invention relates to a coated cooking element (1) for a culinary article or electrical cooking appliance, comprising a metal substrate (2) coated on at least one face (2a) with a coating (3) intended to form a cooking face free of fluorocarbon resin and coated on at least the other face (2b) with a coating (4) comprising at least the following layers and in this order starting from the metal substrate (2): - (4a) primer layer comprising polyethersulfone (PES), - (4b) optionally, one or more intermediate layer(s) comprising polyethersulfone (PES) or a mixture of polyethersulfone (PES) and one or more silicone resins, - (4c) topcoat comprising polyethersulfone (PES) or one or several silicone resins or a mixture of polyethersulfone (PES) and one or more silicone resins.

[0013] Another object of the invention relates to a method of manufacturing a culinary article or electrical cooking appliance comprising a cooking element coated (1) with a coating (4) according to the invention characterized by the following steps:

[0014] a) a step of providing a metal substrate (2) in the form of a substantially flat metal substrate comprising two opposite faces;

[0015] b) optionally, a step of treating at least one face (2a) of the metal substrate (2), to obtain a treated face (2a) promoting the adhesion of a primer layer (4a) on the support (2);

[0016] c) a step of applying the layers (4a), optionally (4b), and (4c) of the coating (4);

[0017] d) optionally a drying step between 50°C and 150°C after application of said layers;

[0018] e) a step of cooking the element obtained in step c) or d) at a temperature between 250°C and 420°C.

[0019] f) a step of shaping the element obtained to give it the shape of a support (2) of convex or hollow shape defining a concave inner face (21) and a convex outer face (22).

[0020] Another object of the invention relates to a culinary article or electrical cooking appliance comprising a coated cooking element (1) according to the invention or capable of being obtained according to the method of the invention, characterized in that the layer (4c) is intended to be placed in contact with a heating source. FIGURES [0021 ] [Fig. 1 ] ; diagram of a cooking element according to the invention in which the coating (4) comprises a layer (4a), a layer (4b) and a layer (4c)

[0022] [Fig.2]; diagram of a culinary article according to the invention

[0023] [Fig.3]: diagram of an electrical cooking appliance according to the invention DETAILED DESCRIPTION

[0024] A first subject of the invention relates to a coated cooking element (1) for a culinary article or electrical cooking appliance, comprising a metal substrate (2) coated on at least one face (2a) with a coating (3) intended to form a cooking face free of fluorocarbon resin and coated on at least the other face (2b) with a coating (4) comprising at least the following layers and in this order starting from the metal substrate (2): - (4a) primer layer comprising polyethersulfone (PES), - (4b) optionally, one or more intermediate layer(s) comprising polyethersulfone (PES) or a mixture of polyethersulfone (PES) and one or more silicone resins, - (4c) topcoat comprising polyethersulfone (PES) or one or several silicone resins or a mixture of polyethersulfone (PES) and one or more silicone resins.

[0025] Advantageously, the layer (4a) is in contact by one of its faces with the metal substrate (2) by its face (2b).

[0026] The coated face (2a) of the metal substrate forms a cooking face. In other words, the coating (3) according to the invention is then intended to be in contact with food. The coating (3) can be a non-stick coating of any kind.

[0027] A person skilled in the art will know how to choose the appropriate coating depending on the household item and its use(s).

[0028] Advantageously, the coating (3) comprises one or more layers. Conventionally, the coating (3) comprises in this order from the substrate (2) one or more primer layer(s), optionally one or more intermediate layer(s) and one or more finishing layer(s).

[0029] The coating (3) does not comprise fluorocarbon resin, also called fluorinated polymer or fluoropolymer. In other words, said coating (3) is free of fluorocarbon resin. Thus, the coating (3) does not comprise or emit perfluoroalkyl and polyfluoroalkyl compounds.

[0030] When the coating (3) comprises several layers, they may be identical or different in the nature of the components, in percentage by weight of the components, in thickness, etc.

[0031] The coating (3) may comprise: - one or more additive(s), and / or, - one or more coloring agent(s), and / or - one or more filler(s).

[0032] The coating (3) may be of organic, inorganic or hybrid nature.

[0033] The other face (2b) of the metal substrate (2) is coated with the coating (4).

[0034] Advantageously, the thickness of each of the layers of the coating (4a), optionally (4b) and (4c) is from 5 μm to 15 μm.

[0035] According to one embodiment, at least one intermediate layer (4b) is present in the coating (4) according to the invention. The at least one intermediate layer (4b) is different from at least one primer layer (4a) and from at least one finishing layer (4c). More preferably, in this case, all the intermediate layers (4b) are different from the primer layer(s) (4a) and from the finishing layer(s) (4c). PES

[0036] According to embodiments, the PES content increases from the primer layer (4a) to the finishing layer (4c).

[0037] Thus, in this case, the PES content in the primer layer (4a) is lower than the PES content in the layer(s) (4b) when they are present, which is itself lower than the PES content of the finishing layer (4c).

[0038] Thus, advantageously, the PES content of the primer layer (4a) represents from 50% to less than 75% by weight of the primer layer (4a), preferably from 55% to 70%.

[0039] Advantageously, the PES content of the intermediate layer (4b), when present, represents from 75 to less than 85% by weight of the intermediate layer (4b), preferably from 75% to 80%.

[0040] Advantageously, the PES content of the finishing layer (4c) represents from 85% to 98% by weight of the finishing layer (4c), preferably from 85% to 95%.

[0041] In these embodiments, advantageously, the layers (4a), (4b) when present, and (4c) comprise polyethersulfone (PES) and optionally: - one or more thermoplastics different from PES and / or - one or more filler(s) and / or - one or more additive(s), and / or - one or more coloring agent(s).

[0042] In these embodiments, advantageously, the layers (4a), (4b) when present, and (4c) comprise polyethersulfone (PES) and one or more fillers.

[0043] In these embodiments, advantageously, the filler content decreases from the primer layer (4a) to the finishing layer (4c).

[0044] According to other embodiments, the PES content decreases from the primer layer (4a) to the finishing layer (4c).

[0045] Thus, in this case, the PES content in the primer layer (4a) is greater than the PES content in the layer(s) (4b), when present, which is itself greater than the PES content of the finishing layer (4c).

[0046] Thus, advantageously, the PES content of the primer layer (4a) represents from 25% to 30% by weight of the primer layer (4a).

[0047] Advantageously, the PES of the intermediate layer (4b), when present, represents from 20% to less than 25% by weight of the intermediate layer (4b).

[0048] Advantageously, the PES of the finishing layer (4c) represents from 10% to less than 20% by weight of the finishing layer (4c), preferably from 15% to less than 20%.

[0049] In these embodiments, advantageously, the layers (4a), (4b) when present, and (4c) comprise a mixture of polyethersulfone (PES) and one or more silicone resins, and optionally: - one or more thermoplastics different from PES, and / or - one or more filler(s) and / or - one or more additive(s), and / or - one or more coloring agent(s).

[0050] In these embodiments, advantageously, the silicone resin content increases from the primer layer (4a) to the finishing layer (4c).

[0051] In these embodiments, advantageously, the PES content decreases from the primer layer (4a) to the finishing layer (4c) and the silicone content increases from the primer layer (4a) to the finishing layer (4c).

[0052] In these embodiments, advantageously, the (PES+silicone resin) content of the layers (4a), (4b) and (4c) ranges from 40% to 90% or from 50% to 90%, preferably from 60% to 90%, even more preferably from 70% to 90% by weight of each layer.

[0053] In these embodiments, the presence of silicone resins and PES makes it possible to confer both the non-stick character of the coating as well as its ability to be drawn in the case where the coated heating element is shaped after deposition of the coating (4).

[0054] These embodiments are thus particularly suitable in the case of shaping the heating element to give it a convex shape, such as for a frying pan, for example.

[0055] According to other embodiments, in particular when the coated heating element is shaped by stamping after deposition of the coating (4) and the coating (4) is subjected to high stresses during this stamping step, the layer (4c) comprises polyethersulfone (PES) and one or more silicone resins and, optionally: one or more thermoplastics other than PES and / or one or more fillers and / or; one or more additive(s) and / or; and one or more coloring agent(s).

[0056] the PES content being between 60% and 80% by weight of the layer (4c), the silicone resin content being between 5% and 30% by weight of the layer (4c) and the (PES+silicone resin) content being between 70% and 98%, preferably between 80% and 98%, even more preferably between 90% and 98% by weight of the layer (4c).

[0057] Advantageously, the PES of the primer layer (4a) represents from 50% to less than 75% by weight of the primer layer, preferably from 55% to 70%. Advantageously, the PES of the intermediate layer (4b), when present, represents from 75 to less than 85% by weight of the intermediate layer, preferably from 75% to 80%.

[0058] The high PES content of layer (4c) as well as layers (4a) and (4b) ensures good drawability under high stress. The presence of silicone resin in layer (4c) also ensures good non-stick properties.

[0059] These embodiments are thus particularly suitable in the case of shaping the heating element to give it a hollow shape for a saucepan for example.

[0060] CHARGES

[0061] Advantageously, the primer layer(s) (4a) and / or the optional intermediate layer(s) (4b) and / or the layer(s) (4c) comprises / comprise one or more fillers. According to this embodiment, the primer layer(s) (4a) and / or the optional intermediate layer(s) (4b) and / or the layer(s) (4c) comprises / comprise less than 40%, preferably less than 30%, by weight of fillers relative to the total weight of said layer, preferably between 5 and 25% by weight.

[0062] The fillers within the meaning of the invention make it possible to provide mechanical reinforcement and can also provide hydrophobicity properties, while improving the mechanical resistance and thermal conductivity of the coating.

[0063] Fillers do not only have the function of providing color to the coating, but can contribute to it.

[0064] Advantageously, the filler(s) is / are chosen from the group consisting of ceramic fillers (SiO2, etc.) and / or mineral and / or metallic fillers (A12O3, TiO2, etc.) and / or silicas and / or diamond particles.

[0065] Preferably, the filler(s) is / are chosen from the group consisting of metal oxides, metal carbides, metal oxynitrides, metal nitrides, and mixtures thereof.

[0066] Advantageously, said metal is a transition metal, such as at least one of the elements chosen from B, Ni, Ti, Zr or Hf.

[0067] More preferably, the filler(s) is / are chosen from the group consisting of:

[0068] - fillers for reinforcement: organic or inorganic hard fillers; the fillers inorganic hard particles are preferably particles of silicon carbides or alumina or zirconia or graphite, or ceramics, or carbonate, or hydrated alumina, aluminum trihydroxide or one or more metal oxide(s), graphite, graphene;

[0069] - other fillers for reinforcement chosen from metal oxides: silica, micas, lamellar fillers, clays such as montmorillonite, sepiolite, gypsite, kaolinite and laponite, zinc dioxide, quartz, and zirconium phosphate, alumina, zirconia, zinc oxide, copper oxide, iron oxide;

[0070] - fillers chosen from reinforcing fibers: glass or carbon fiber or aramid;

[0071] - conductive fillers comprising a transition metal carbide and / or a nitride of transition metal: characterized in that the transition metal is at least one of the elements chosen from B, Ni, Ti, Zr or Hf,

[0072] for example: Cubic Boron Nitride, diamond particles, metal particles;

[0073] - lamellar fillers capable of conferring lubricating properties, such as example clays, graphene or graphite.

[0074] Among the fillers in combination with silicone resins, the preferred fillers are:

[0075] - reinforcing fillers: silica or carbonates with minimum filler rates 10-15% / wt and up to 60% / wt,

[0076] - alumina, hydrated alumina, aluminum trihydroxide,

[0077] - silica (precipitated or pyrogenic) with a d50 <0.1 pm and a specific surface area BET > 30 m2 / g and preferably between 30 and 500 m2 / g,

[0078] - or mixture of quartz and silica, diatomaceous earth or ground quartz, titanium, mica, talc, kaolin, barium sulfate, slaked lime, zinc oxide, expanded vermiculite, unexpanded vermiculite, calcium carbonate etc.

[0079] More preferably, the filler(s) is / are chosen from the group consisting of alumina, silicon carbide, tungsten carbide, boron nitride, quartz, and mixtures thereof.

[0080] Advantageously, the fillers present in the primer layer(s) (4a) or the optional intermediate layer(s) (4b) are inorganic hard fillers, preferably metal oxides, carbides, nitrides, preferably alumina, silicon carbides or fumed silica.

[0081] Certain inorganic hard fillers such as silicon carbide, in addition to their mechanical reinforcement performance, also have the advantage of being conductive fillers and therefore provide excellent thermal conductivity.

[0082] The addition of this type of filler makes it possible to improve the culinary rendering with better diffusion of heat from the metal substrate to the food in contact with the coating.

[0083] Advantageously, the average diameter d50 of the charges is between 0.1 and 50 pm, advantageously still between 5 and 15 pm.

[0084] Advantageously, the proportion of fillers in a layer is between 0.5 and 30% by dry weight relative to the total weight of said layer after cooking, preferably between 5 and 20%.

[0085] Advantageously, the proportion of fillers in the layer (4a) is greater than 20% by weight, preferably greater than 30% by weight, relative to the total weight of said layer.

[0086] Advantageously, the proportion of fillers in the layer (4c) is less than 10% by weight relative to the total weight of said layer.

[0087] Advantageously, the proportion of fillers in layers (4a), (4b) and (4c) may be identical or different.

[0088] Advantageously, the nature of the charges in layers (4a), (4b) and (4c) may be identical or different.

[0089] ADDITIVES

[0090] Advantageously, the primer layer(s) ('a) and / or the intermediate layer(s) (4b) and / or the layer(s) (4c) comprises / comprise one or more additives.

[0091] Advantageously, the additive(s) is / are chosen from the group consisting of anti-foaming agents, dispersing agents, wetting agents, thickeners, pH adjusters, reactive silicone oils.

[0092] Said anti-foaming agent(s) are preferably chosen from the group consisting of mineral oils, diols, hydrocarbons, glycerides, oxirane, emulsified fatty acids.

[0093] The surfactant(s) is (are) preferentially chosen from the group consisting of glycol ether, ethoxylated alcohol excluding alkyl phenol ethoxylates (APE), gemini surfactants.

[0094] The dispersing agent(s) is (are) preferentially chosen from the group consisting of anionic dispersants such as fatty acid derivatives.

[0095] Said thickeners are preferably chosen from the group consisting of acrylic-based or polyurethane-based copolymer, cellulose, pyrogenic silica.

[0096] Said pH adjusters are preferably chosen from the group consisting of Bronsted bases: ammonia, amines (triethylamine, triethanolamine, etc.), hydroxides (soda, potash, etc.), carbonates.

[0097] Advantageously, the primer layer(s) (4a) and the intermediate layer(s) (4b) comprise one or more acrylic resin(s). The acrylic resin(s) is / are advantageously chosen from the group consisting of polymers resulting from an emulsion polymerization of different monomers with other acrylic-based monomers.

[0098] Advantageously, the primer layer(s) (4a) or the intermediate layer(s) (4b) comprises / comprise one or more surfactants.

[0099] Advantageously, the primer layer(s) (4a) or the intermediate layer(s) (4b) further comprises one or more anti-foaming agents.

[0100] Advantageously, the primer layer(s) (4a) or the optional intermediate layer(s) (4b) further comprises / comprise water and / or one or more solvents, preferably unlabeled, for example propionamide, N-formylmorpholine (NFM), N-Methyl Imidazole (NMI), N-ButylPyrrolidone (NBP), di-methylsulfoxide (DMSO), or alcoholic, for example Propylene Glycol (PPG), Die- ethylene glycol, dipropylene glycol butyl ether (DPNB).

[0101] Advantageously, the finishing layer (4c) comprises a silicone oil. The presence of a silicone oil in the finishing layer can make it possible to improve the stretchability of the coating (4) when the latter is subjected to mechanical stresses, such as during shaping by stamping for example.

[0102] Advantageously, the silicone oil represents from 1 to 5% by weight of the finishing layer (4c), preferably from 2% to 4%.

[0103] COLOURING AGENTS

[0104] Advantageously, the primer layer(s) (4a) or the optional intermediate layer(s) (4b) comprises / comprise one or more coloring agent(s). Advantageously, the primer layer(s) (4a) or the optional intermediate layer(s) (4b) comprises / comprise less than 30%, preferably less than 20%, by weight of one or more coloring agent(s) of the total weight of said layer.

[0105] Advantageously, the coloring agent(s) is / are chosen from the group consisting of thermostable pigments, glitter, preferably hologram glitter, and mixtures thereof.

[0106] The proportion of coloring agents in layers (4a), (4b) and (4c) may be between 0.5 and 50% by dry weight relative to the total weight of said layer after cooking.

[0107] Advantageously, the proportion of coloring agents in layers (4) and (4b) ranges from 10% to 40% by weight relative to the total weight of said layer.

[0108] Advantageously, the proportion of coloring agents in the layer (4c), when they are present, is less than 10% by weight relative to the total weight of said layer.

[0109] Advantageously, the proportion of coloring agents in layers (4a), (4b) and (4c) may be identical or different.

[0110] Advantageously, the nature of the coloring agents in layers (4a), (4b) and (4c) may be identical or different.

[0111] Advantageously, the layer (4c) is transparent. In this case, if it comprises coloring agents, these coloring agents are glitter. Thermostable pigments

[0112] Preferably, the thermostable pigment(s) is / are chosen from the group consisting of:

[0113] - Yellow titanium rutile pigment,

[0114] - Yellow pigment derived from bismuth, for example selected from vanadates of stabilized bismuth (Pyi84)

[0115] - Red pigment, for example selected from perylene red (for example PR149, PR178 and PR224), iron oxide,

[0116] - Orange pigment of bismuth oxyhalides type (PO85),

[0117] - Bismuth vanadate orange pigment (PO86)

[0118] - Zinc tin titanium orange pigment (PO82)

[0119] - Cerium sulfide orange pigment (PO75; PO78)

[0120] - Orange-yellow pigment of the antimony titanium chrome rutile type (PBr24)

[0121] - Orange-yellow pigment of tin and zinc rutile type (Py2i6)

[0122] - Niobium tin zinc sulfide orange-yellow pigment (Py227)

[0123] - Orange-yellow pigment of double oxides of tin and niobium

[0124] - Co3(PO4)2

[0125] - LiCoPO4

[0126] - CoA12O4

[0127] - Cr2O3

[0128] - TiO2

[0129] - Black pigment PBk28 (Copper chromite black spinel)

[0130] - and their mixtures. Sequins

[0131] The flakes that can be used in the context of the present invention can be independently chosen from mica flakes, coated or not, silica flakes, coated or not, aluminum flakes, coated or not, iron oxide flakes, coated or not. Mica or silica flakes coated with titanium dioxide. The flakes that can be used in the context of the present invention can be treated to give a particular color effect.

[0132] Advantageously, the flake(s) is / are particles chosen from the group consisting of particles of mica, aluminum, mica coated with titanium dioxide or mixtures thereof. Hologram sequins

[0133] Advantageously, the glitter(s) is / are hologram glitter, that is to say a mixture of magnetizable particles and non-magnetizable particles.

[0134] The magnetizable particles may advantageously be particles comprising at least one ferromagnetic metal. These magnetizable particles may be of a homogeneous nature, i.e. made of the same material, or of a composite nature, i.e. these magnetizable particles have a core-shell structure, in which the ferromagnetic metal is found in the core and / or in the shell of said particles. Examples of composite magnetizable particles include mica flakes coated with iron oxide Fe2O3 or stainless steel fibers coated with a sol-gel material, as protection against corrosion during the steps of implementing the coating, or or flakes made of plastic material coated with iron oxide Fe2O3, or flakes whose core is made of ferromagnetic metal and the shell is made of a plastic material or a sol-gel material.

[0135] According to one embodiment, a portion of said magnetizable particles is oriented so as to form a three-dimensional decoration.

[0136] Advantageously, the mixture of magnetizable particles and non-magnetizable particles represents between 1% and 5% by weight of the weight of the layer, preferably between 2% and 3% by weight.

[0137] Advantageously, the percentage of non-magnetizable particles in the mixture of magnetizable particles and non-magnetizable particles is between 15% and 40% by weight relative to the total weight of the mixture of magnetizable particles and non-magnetizable particles.

[0138] Advantageously, the magnetizable particles have a dimension D50 less than or equal to 23 pm.

[0139] By the term “D50” is meant, within the meaning of the present invention, the maximum dimension presented by 50% of the particles in number.

[0140] Advantageously, the non-magnetizable particles have a dimension D90 of between 20% and 250% of the dimension D90 of the magnetizable particles.

[0141] By the term “D90” is meant, within the meaning of the present invention, the maximum dimension presented by 90% of the particles in number.

[0142] Advantageously, the magnetizable particles and / or the non-magnetizable particles are colored on the surface.

[0143] Advantageously, the non-magnetizable particles consist of mica, aluminum, or mica coated with titanium dioxide.

[0144] Advantageously, the magnetizable particles consist of iron, iron oxide, iron-coated aluminum, or iron-coated mica, the iron being in ferritic form.

[0145] THERMOPLASTICS

[0146] Thermoplastics are thermoplastic polymers.

[0147] Advantageously, the thermoplastic polymer(s) other than PES is / are chosen from the group consisting of polyaryletherketone(s) (PAEK), aromatic thermoplastic polymer(s) such as poly(arylethersulfones) (PAES), poly(arylene sulfides) (PAS) or poly(phenylene oxide) (PPO), liquid crystal polymers, heterocyclic thermoplastic polymers and mixtures thereof.

[0148] PAEK

[0149] Advantageously, the polyaryletherketone(s) (PAEK) is (are) chosen from the group consisting of: polyetherketones (PEK), polyetheretherketone (PEEK), poly- etherketoneketones (PEKK), polyetheretherketoneketones (PEEKK) and polyetherketo-neetherketoneketones (PEKEKK), particularly preferably is (are) PEEK.

[0150] Other aromatic thermoplastic polymers

[0151] As aromatic thermoplastic polymer(s), examples which are suitable according to the invention are poly(phenylene oxide) (PPO), poly(arylethersulfone) polymer (PAES), with the exception of polyethersulfone (PES), poly-phenylene ether sulfone (PPSU), poly(arylene sulfides) (PAS) and in particular polyphenylene sulfide (PPS), liquid crystal polymers and their mixtures.

[0152] Heterocyclic thermoplastic polymers

[0153] As heterocyclic thermoplastic polymers, examples suitable according to the invention are polyetherimides (PEI), polyimides (PI), polyamideimides (PAI) and polybenzymidazole (PBI), or mixtures thereof.

[0154] Advantageously, the thermoplastic polymer(s) is / are chosen from the group consisting of polyethersulfone (PES), polyphenylene ether sulfone (PPSU), polyamideimide (PAI), polyimide (PI), poly(phenylene oxide) (PPO), poly(arylene sulfide) (PAS), polyetherimide (PEI), polybenzymidazole (PBI), liquid crystal polymers (LCP), polyphenylene sulfide (PPS), polyarylether ketone (PAEK) including polyether ketone (PEK), polyether ether ketone (PEEK), polyether ketone ketone (PEKK), polyether ether ketone ketone (PEEKK), polyether ketone ether ketone ketone (PEKEKK) and mixtures thereof.

[0155] Advantageously, the nature of the thermoplastic polymer(s) in the layers (4a), (4b) and (4c) may be identical or different.

[0156] SILICONE RESINS

[0157] In the text of the description, the expression "silicone resin" is used indifferently to refer to the silicone before its crosslinking or after its crosslinking. In the text of the description, the expression "silicone" designates an organo-lysiloxane material. Crosslinking is the step which makes it possible to transform the silicone into an insoluble material, for example by polyaddition, polycondensation or dehydrogenation. Crosslinking is carried out from precursors which are generally silicone oils or resins, which crosslink to obtain a three-dimensional network forming a material called silicone resin, in the description.

[0158] This crosslinking can be done by thermal activation, or chemical activation using a catalyst, such as platinum.

[0159] The silicone resins can be obtained from precursors, advantageously soluble in a solvent or in emulsion in water, such as oils or crosslinkable resins, notably chosen from: a silicone hydride, a silicone oil resin comprising at least one vinyl group (-CH=CH2), a silicone resin or silicone- polyester (copolymer) comprising at least one alkoxy group, for example methoxy or ethoxy, and / or a silicone or silicone-polyester resin (copolymer) comprising at least one alkoxy group, in particular ethoxy, or a hydroxy group and mixtures thereof. These precursors have the ability to crosslink in order to obtain a silicone resin which is characterized by its insolubility and its substantially solid form.

[0160] Advantageously, these precursors are polymeric or oligomeric, either in the form of silicone oils with a variable degree of branching, or in the form of silicone resins with a variable degree of pre-crosslinking or copolymers of silicone resins such as silicone-polyester, silicone-alkyd, silicone-polyurethane, silicone-epoxy resins, or in the form of a mixture of silicone oils, silicone resins and copolymers of silicone resins. The silicon atoms may be substituted by alkyl (in particular methyl) or aryl (in particular phenyl) groups or mixtures thereof. The oils or resins preferably comprise one or more (2, 3 or more) hydroxy or alkoxy (in particular methoxy, ethoxy, butoxy) functional groups as substituents of silicon atoms.

[0161] Advantageously, the silicone resin(s), obtained after crosslinking their precursors, i.e. crosslinked, is / are chosen from the group consisting of methyl silicone and / or phenyl silicone and / or methyl-phenyl-silicone resins, methyl silicone-polyester resin (copolymers), phenyl silicone-polyester resin (copolymers), methyl-phenyl silicone-polyester resin (copolymers), silicone-alkyd resin (copolymers), modified silicone resin and mixtures thereof.

[0162] Advantageously, the silicone resin(s) is / are chosen from the group consisting of methyl silicone and / or phenyl silicone and / or methyl-phenyl-silicone resins, methyl silicone-polyester resin (copolymers), phenyl silicone-polyester resin (copolymers), methyl-phenyl silicone-polyester resin (copolymers), silicone-alkyd resin (copolymers), modified silicone resin and mixtures thereof.

[0163] The silicone resins can be obtained from precursors, notably chosen from: a silicone hydride, a silicone resin comprising at least one vinyl group (-CH=CH2), a silicone-polyester resin (copolymer) comprising at least one methoxy group, and / or a silicone-polyester resin (copolymer) comprising at least one ethoxy group, and mixtures thereof.

[0164] The silicone resin forms a network which may consist of a combination of 4 simple organosiloxane units called M, D, T and Q depending on the degree of substitution by oxygen of the silicon atom, as described in the following table, where R is an organic substituent described below.

[0165] [Tables 1]

[0166] The organopolysiloxane material or polymer is obtained by crosslinking from precursors which can be monomeric or polymeric, or intermediately which can be oligomeric. The organopolysiloxane polymer can also be obtained from a mixture of these different kinds of precursors. When the network contains a higher number of T and Q units than D, the crosslinking density is higher. The distribution between the M, D, T and Q units depends on the chemical structure of the precursors, in particular on this M, D, T, Q distribution within the precursors.

[0167] The polymeric precursors are organopolysiloxanes. These macromolecules are formed from M, D, T, and / or Q units as described in the table, where R is independently an alkyl group, in particular methyl, or aryl, in particular phenyl, different natures of R being able to be present on the same macromolecule.

[0168] Organopolysiloxanes can be either linear or slightly branched (majority of D groups), or branched or highly branched (majority of T and Q groups). Linear or lightly branched organopolysiloxanes are generally liquid, more or less viscous at room temperature, and are called silicone oils. Branched or highly branched (pre-crosslinked) organopolysiloxanes constitute a network at the scale of the individual macromolecule and are called silicone resins. At room temperature, the resins are substantially in solid form, or in liquid form provided in particular that they have a fairly low molecular weight, in the form of a solution in a solvent or in the form of an aqueous emulsion. They can be copolymerized with organic polymers or oligomers not containing silicon, chosen in particular from polyesters, acrylics, alkyds, polyurethanes, epoxy resins.

[0169] When the crosslinking is a hydrolysis-polycondensation: it is carried out thanks to the reactive hydroxy or alkoxy functions, in particular methoxy, ethoxy or butoxy, present on the organopolysiloxane.

[0170] When the crosslinking is a polyaddition (or hydrosilylation): it is carried out by reaction between the reactive vinyl functions (-CH=CH2) present on one of the organopolysiloxanes and the reactive silyl hydride functions (Si-H) present on the other organopolysiloxane mixed with the first.

[0171] All these reactive functions are present on each organopolysiloxane in the number of at least one and can be present in the number of 2, 3, or more ... as much as the molecular structure allows. Silicone oils comprising at least one reactive function are called "reactive oils". The reactive functions can be found either at the end of the macromolecular chain (termination), or distributed over the chain.

[0172] The silicone-polyester resins in particular have silicone / polyester mass ratios for example 90 / 10, 80 / 20, 70 / 30, 60 / 40, 50 / 50, 40 / 50, 30 / 70, 20 / 80, 10 / 90, advantageously between 80 / 20 and 50 / 50.

[0173] Linear PDMS silicone oils, pure or pre-emulsified in water, are characterized firstly by their molecular mass, which is a direct increasing function of the viscosity of the pure oil. They are then characterized by the presence or absence of reactive functions, for example hydroxyls on the silicon atoms (silanol), their number and their location on the molecular chain. For example, reactive oils with viscosities of between 50 and 20,000 mPa.s, and in particular between 300 and 5,000 mPa.s, can be used, having at least one reactive function, preferably at least 2, which can be placed at the end of the chain.

[0174] Polymer precursors reacting by polyaddition may include, for example, polymethylhydrosiloxane, vinylmethylsiloxane, vinyl-terminated polydimethylsiloxane (PDMS), in particular linear, vinyl-terminated diphenylsiloxane-dimethylsiloxane copolymers, hydride-terminated polydimethylsiloxanes, hydride-terminated polyphenylmethylsiloxanes, cyclic vinylmethylsiloxane, vinyl-MQ resin, trimethylsilyl-terminated polymethylhydrosiloxane, trimethylsiloxane-terminated dimethylsiloxane copolymer, MQ resin hydride, and the like, as well as combinations thereof.

[0175] The polymeric precursors reacting by hydrolysis-polycondensation, whether they are silicone resins or silicone oils, may include for example poly(methylsilsesquioxanes), poly(propylsilsesquioxanes), poly(phenylsilsesquioxanes), polydimethylsiloxane (PDMS), polydimethyl-siloxane (PDMS), trimethylsilyl terminated, polydimethylsiloxane (PDMS) terminated hydroxyl, polydimethylsiloxane (PDMS) terminated silanol, polyphenylsiloxane (PDMS) terminated silanol, diphenylsiloxane-dimethylsiloxane copolymer terminated silanol, poly(2-acetoxyethylsilsesquioxanes), organomodified alkoxy-silanes and their oligomers, and all similar macromolecules as well as their mixtures.

[0176] The organopolysiloxane material or polymer may also be obtained by crosslinking a mixture of one or more monomeric precursors and one or more polymeric precursors as described above, as well as one or more oligomeric precursors which may be linear, branched or cyclic. These oligomeric precursors have a lower molecular weight than the polymeric precursors. Polymeric and / or oligomeric precursors comprising a number of reactive functions as described above greater than 2, advantageously much greater than 2, may be added to the mixture as a “co-binder” in order to promote a high crosslinking density of the organopolysiloxane polymer finally obtained.

[0177] The monomeric, oligomeric and / or polymeric precursors, in particular silicone resins, copolymerized or not with an organic polymer, play the role of polymeric binder in order to obtain the solid organopolysiloxane polymer combined with the thermoplastics of each layer.

[0178] Silicone oil type organopolysiloxane precursors can be considered as additives if they are added in small quantity (generally between 0.1 and 5% dry) in the whole formula of a layer, independently of the other components for the formation of the solid organopolysiloxane polymer.

[0179] Crosslinking may require a catalyst:

[0180] - In the case of crosslinking of organopolysiloxanes by hydrolysis-polycon densation, the formula may include a metal catalyst, such as, for example, metal complexes based on platinum, tin, zinc, zirconium and cerium, in particular platinum-cyclovinylmethyl-silxane complexes, tin ethylhexanoate, zinc ethylhexanoate, zirconium ethylhexanoate, cerium ethylhexanoate, and tin dibutyl laurate.

[0181] - In the case of the crosslinking of organopolysiloxanes by hydrosylilation, the addition a catalyst may be necessary: ​​this may be, for example, platinum or a suitable platinum-based catalyst such as the Karstedt catalyst or the Ashbys catalyst.

[0182] A crosslinking agent, for example carrying Si-H bonds, may be present.

[0183] OTHER ARCHITECTURES

[0184] Preferably, the intermediate layer(s) (4b) only partially cover the base layer (4a).

[0185] According to one embodiment, the finishing layer (4c) is made up of one or more silicone resins, and optionally: - one or more fillers and / or - one or more additive(s), and / or - one or more coloring agent(s).

[0186] According to one embodiment, the layer (4c) is made up of:

[0187] - of a silicone elastomer obtained from at least one carrier organopolysiloxane of reactive vinyl functions (-CH=CH2), at least one other organopolysiloxane carrying reactive silyl hydride functions (Si-H), preferably in the presence of a metal catalyst; and optionally:

[0188] - of one or more thermoplastics

[0189] - of one or more charge(s), and / or

[0190] - one or more additive(s), and / or

[0191] - one or more coloring agents.

[0192] when at least one layer (4b) is present.

[0193] In this case, advantageously, the PES content increases from layer (4a) to layer (4b). Layer (4a) and layer (4b) may be as described above.

[0194] The organopolysiloxanes carrying reactive functions of layer (4c) are precursors which react by a crosslinking which is a polyaddition (or hydrosilylation). This crosslinking is carried out by reaction between the vinyl reactive functions (-CH=CH2) present on one of the organopolysiloxanes and the silyl hydride reactive functions (Si-H) present on the other organopolysiloxane mixed with the first.

[0195] This crosslinking can be done by thermal activation, or chemical activation using a catalyst.

[0196] Advantageously, the organopolysiloxanes carrying reactive functions of layer (4c) are silicone oils.

[0197] The reactive functions are present on each organopolysiloxane in the number of at least one and can be present in the number of 2, 3, or more ... as much as the molecular structure allows. Silicone oils comprising at least one reactive function are called "reactive oils". The reactive functions can be found either at the end of the macromolecular chain (termination), or distributed over the chain.

[0198] The addition of a catalyst may be necessary for crosslinking: this may be, for example, platinum or a suitable platinum-based catalyst such as the Karstedt catalyst or the Ashbys catalyst.

[0199] The thermoplastics, additives and coloring agents are as described above. The thermoplastic of layer (4c) may also be PES.

[0200] Advantageously, the thickness of the finishing layer (4c) is from 0.1 μm to 10 μm, preferably from 0.5 μm to 5 μm, particularly preferably from 1 μm to 2 μm.

[0201] METAL SUBSTRATE

[0202] Advantageously, said metal substrate (2), also called support, is a substrate made of aluminum, stainless steel, cast iron or aluminum, iron, titanium or copper.

[0203] For the purposes of the present invention, aluminum means a metal consisting of 100% aluminum or an aluminum alloy.

[0204] Advantageously, the metal substrate (2) is an aluminum substrate, a stainless steel substrate or a multi-layer metal substrate. The metal substrate (2) may be a two-layer or three-layer substrate, these multi-layers being able to be obtained for example by co-lamination, by hot diffusion under load (solid State bonding) or by hot or cold impact bonding.

[0205] Preferably, the metal substrate (2) comprises an alternation of layers of metal and / or metal alloy.

[0206] According to one embodiment, the metal substrate (2) is a substrate made of aluminum alloy, stainless steel or a multi-layer metal substrate whose face (2a) is made of aluminum alloy or stainless steel.

[0207] Preferably, the metal substrate (2) is an aluminum substrate.

[0208] Advantageously, the thickness of the metal substrate (2) is between 0.5 mm and 10 mm.

[0209] Advantageously, the face (2a) of the metal substrate (2) has previously undergone a surface treatment making it possible to improve the adhesion of the coating to said substrate.

[0210] According to one embodiment, the surface of the face (2a) of the metal substrate (2) has undergone a surface treatment, said surface treatment being a chemical attack, brushing, hydration, sandblasting, shot blasting, a physicochemical treatment of the plasma or corona or laser type, a chemical activation or a combination of these different techniques.

[0211] Advantageously, the face of the substrate (2a) on which the coating (3) according to the invention will be applied can be treated so as to increase its specific surface area; for an aluminum substrate, this treatment can be done by anodization (creation of a tubular alumina structure), by chemical attack, by sandblasting, by brushing, by shot blasting or by adding material by means of a technology such as thermal projection (flame, plasma or arc spray). The other metal substrates can also be polished, sandblasted, brushed, micro-blasted or receive an addition of material by means of a technology such as thermal projection (flame, plasma or arc spray).

[0212] As metallic substrates which can be used in the present invention, mention may advantageously be made of anodized or non-anodized aluminum substrates, optionally polished, brushed, sandblasted, shot-blasted or micro-blasted, anodized or non-anodized aluminum alloy substrates, optionally polished, brushed, sandblasted or micro-blasted, steel substrates, optionally polished, brushed, sandblasted, shot-blasted or micro-blasted, stainless steel substrates. possibly polished, brushed, sandblasted or microblasted, substrates made of cast steel, aluminum or iron, substrates made of copper possibly hammered or polished.

[0213] Advantageously, the substrate may be chosen from substrates comprising ferritic stainless steel / aluminum / austenitic stainless steel layers, substrates comprising stainless steel / aluminum / copper / aluminum / austenitic stainless steel layers, cast aluminum, aluminum or aluminum alloy caps lined with an outer base of stainless steel, metallic co-laminated substrates, for example two-layer co-laminated substrates comprising a stainless steel layer (for example intended to constitute the inner face of the article) and a layer of aluminum or aluminum alloy, anodized or not (for example intended to constitute the outer face of the article).

[0214] Advantageously, the average arithmetic roughness Ra of the surface of the face (2a) of the metal substrate (2) is greater than or equal to 1 pm.

[0215] The arithmetic mean roughness Ra is measured using a roughness meter according to ISO 4287. Ra represents the arithmetic mean of the deviations from the mean. The surface topography can be studied in particular with a profilometer with a probe equipped with a fine stylus fitted with a diamond tip, or with an optical metrology device such as Altisurf®, in which a chromatic confocal sensor allows a contactless measurement. The study of this surface topography makes it possible to define the arithmetic mean roughness Ra.

[0216] METHOD

[0217] The invention also relates to a method of manufacturing a coated cooking element (1) with a coating (4) for a household article according to the invention, characterized by the following steps:

[0218] a) a step of providing a metal substrate (2) comprising two opposite faces;

[0219] b) optionally, a step of treating at least one face (2a) of the metal substrate (2), to obtain a treated face (2a) promoting the adhesion of a primer layer (4a) on the support (2);

[0220] c) a step of applying the layers (4a), optionally (4b) and (4c) of the coating (4);

[0221] d) optionally a drying step between 50°C and 100°C after application of said layers;

[0222] e) a step of cooking the element obtained in step c) or d) at a temperature between 250°C and 400°C

[0223] The invention also relates to a method for manufacturing a culinary article or electrical cooking appliance comprising a heating element coated (1) with a coating (4) according to the invention, characterized by the following steps:

[0224] a) a step of providing a metal substrate (2) in the form of a substantially flat metal substrate comprising two opposite faces;

[0225] b) optionally, a step of treating at least one face (2a) of the metal substrate (2), to obtain a treated face (2a) promoting the adhesion of a primer layer (4a) on the support (2);

[0226] c) a step of applying the layers (4a), optionally (4b), and (4c) of the coating (4);

[0227] d) optionally a drying step between 50°C and 150°C after application of said layers;

[0228] e) a step of cooking the element obtained in step c) or d) at a temperature between 250°C and 420°C;

[0229] f) a step of shaping the element obtained to give it the shape of a support (2) of convex or hollow shape defining a concave inner face (21) and a convex outer face (22).

[0230] Advantageously, during step c), the layer(s) (4a), (4b) and (4c) is / are applied by pad printing, electrostatic powdering, spray spraying, screen printing, roller application or digital printing, preferably by spraying. Advantageously, the spraying is carried out in a solvent-based or aqueous phase.

[0231] Advantageously, when the layer (4c) is made up of:

[0232] - of a silicone elastomer obtained from at least one carrier organopolysiloxane of reactive vinyl functions (-CH=CH2), at least one other organopolysiloxane carrying reactive silyl hydride functions (Si-H), preferably in the presence of a metal catalyst; and optionally:

[0233] - of one or more thermoplastics

[0234] - one or more charge(s), and / or

[0235] - one or more additive(s), and / or

[0236] - one or more coloring agents

[0237] when at least one layer (4b) is present, the method according to the invention may comprise a step of crosslinking g) of the finishing layer (4c) subsequent to or simultaneously with step d).

[0238] According to a variant, the crosslinking of the composition of the layer (4c) can generally be activated, for example, by heat treatment, at a temperature between 50 and 400°C, preferably between 50 and 300°C, obviously taking into account the maximum resistance of the support to heat.

[0239] Advantageously, the crosslinking g) of the layer (4c) is carried out at a temperature of 300°C for a duration of 10 min.

[0240] Advantageously, the higher the crosslinking temperature, the longer the re- ticulation is short.

[0241] According to a variant, the crosslinking step g) does not require heat treatment, in particular because the support is hot at the time of step g).

[0242] Advantageously, during step c), this finishing layer (4c) is applied by electrostatic powdering, spray spraying, screen printing, spray gun, doctor blade, coating cylinder, brush, roller application or digital printing, preferably by spraying.

[0243] According to an advantageous arrangement of the invention, this finishing layer (4c) is applied to the coated support at a deposition rate of less than or equal to 5 g / m2, preferably between 0.1 and 2.5 g / m2, even more preferably between 0.2 and 2 g / m2.

[0244] Advantageously, the steps of the method according to the invention make it possible to coat the metal support (2) with a coating (4) formed by the layers (4a), optionally (4b) and (4c). Generally, these layers are wet when they are applied. By wet layer, it is understood within the meaning of the present invention that the layer comprises all or part of its solvents.

[0245] Shaping is also called stamping.

[0246] When the shaping step precedes the application d) of the coating, the coating is preferably carried out by spraying.

[0247] When this shaping step is subsequent to the application d) of the coating, the coating is preferably carried out by screen printing or by roller.

[0248] ARTICLE

[0249] The invention also relates to a culinary article or an electrical cooking appliance comprising a cooking element coated according to the invention or capable of being obtained according to the method of the invention.

[0250] Advantageously, the culinary article (100) according to the invention is chosen from the group consisting of saucepan, frying pan, skillets or caquelons for fondue or raclette, stewpot, wok, sauté pan, crepe maker, grill, griddle, pot, casserole dish, cooker or bread machine bowl, culinary mold, molds and plates for pastry, barbecue plates and grills, preparation bowls.

[0251] According to one embodiment, the culinary article (100) comprises a heating face (6) intended to be placed in contact with an external heating source, the heating face (6) being opposite the cooking face (5) intended to be placed in contact with the food during cooking.

[0252] The culinary article according to the present invention may in particular be a culinary article of which one of the two opposite faces of the substrate is an inner face, possibly concave, intended to be arranged on the side of food likely to be introduced into or onto said article, and of which the other face of the substrate is an outer face, possibly actually convex, intended to be placed towards a heat source.

[0253] Advantageously, the electric cooking appliance (200) is chosen from the group consisting of electric crepe maker, electric raclette appliance, electric fondue appliance, electric grill, electric griddle, electric cooker, bread maker, electric pressure cooking appliance, waffle makers, rice cookers and jam makers.

[0254] The electrical cooking appliance (200) comprises a coated cooking element (1) according to the invention and a heating source (210) configured to heat said coated cooking element (1). EXAMPLES

[0255] The aims, aspects and advantages of the present invention will be better understood from the description given below of a particular embodiment of the invention presented by way of non-limiting example.

[0256] Of course, the invention is in no way limited to the embodiment described and illustrated, which has been given only as an example. Modifications remain possible, in particular from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

[0257] 1) Examples of implementation:

[0258] Raw materials: - PES resin • PolyEtherSulfone (PES) powder resin, micronized grade from SUMITOMO, polymer powder with a d50 between 11 and 15 pm. - Solvents: • propionamide - Reinforcement charges: • Alumina, • Silicon Carbide • Pyrogenic silica, • Colloidal silica • Colloidal alumina • Mica - Thickener: • 50% acrylic polymer solution in water • hydrogenated castor oil - Silicone resins: • Methyl-phenyl silicone resin, in flakes • Methyl silicone resin, in flakes - Alcohol Solvent • di propylene glycol butyl ether (DPNB), • MPG propylene glycol - Surfactant: • Fatty alcohol polyglycol ether - Anti-foam agent • Mineral oil - Pigments: • Mica or glitter • Carbon black: - Silicone oil: • A: non-reactive • B: reactive - Other additives: • buffering agent • anionic ester in ethanol / water, wetting agent, • aqueous dispersion of polydimethylsiloxane gum, surface tension agent

[0259] Examples of production of a culinary article according to the invention:

[0260] On a flat aluminum disc (30 cm in diameter), previously degreased and sandblasted to obtain a roughness of 4 to 7 pm (Ra), a continuous layer 3a is deposited by screen printing, chosen from the base layer compositions (4al and 4a2) as described below: Layers 4a:

[0261] Layer 4al: Material Nature % wet % in cooked film Solvent DEMINERALIZED WATER 29.57 0.00 Solvent PROPIONAMIDE 22.18 0.00 Thermoplastic polymer PES 18.48 59.19 Wetting agent Fatty alcohol polyglycol ether 0.52 0.07 Acrylic thickener Acrylic polymer solution (50% in water) 5.48 1.95 Buffering agent Amino alcohol 1.05 0.00 Pigment Carbon black 4.13 4.14 Antifoam Mineral oil 1.24 0.20 Reinforcing filler Colloidal silica 4.13 4.01 Reinforcing filler Colloidal alumina 9.50 18.41 Reinforcing filler Silicon carbide 3.72 12.03 100.00 100 Layer 4a2: Material Nature % wet % in cooked film Silicone resin Methyl or methyl-phenyl silicone resin 18.75 45.07 Solvent Alcohol Glycol ether 18.75 0.00 Thickener Hydrogenated castor oil 0.62 1.45 Reinforcing filler Mica 1.87 4.79 Reinforcing filler Pyrogenic silica 1.25 3.20 Pigment Carbon black 3.75 2.97 Reinforcing filler Alumina 1.87 4.79 Wetting agent Fatty alcohol polyglycol ether 1.19 0.12 Solvent DEMINERALIZED WATER 14.56 0.00 Solvent PROPIONAMIDE 10.92 0.00 Thermoplastic polymer PES 10.92 27.66 Acrylic thickener 50% acrylic polymer solution in water 0.73 0.21 Buffering agent Amino alcohol 0.11 0.00 Spreading agent Anionic ester in ethanol / water 1.25 1.12 Solvent Alcohol Propylene glycol 5.94 0.00 Reinforcing filler Colloidal alumina 3.75 5.74 Reinforcing filler Colloidal silica 3.75 2.88 100.00 100

[0264] The thickness of this base layer 4a of the example is between 5 pm and 15 pm.

[0265] The substrate, on which the continuous base layer 4a as described above is applied, is coated with a multi-layer non-stick coating composed of an intermediate layer 4b (5-15 pm) which is dried at 80°C and a finishing layer 4c (5-15 pm). The whole being finally heated to 300°C for approximately 10 min, i.e. the process comprises only one baking step, after the deposition of the different layers. Layers 4b:

[0266] The compositions of the intermediate layers 4b deposited by screen printing are as described below (layer 4b 1 and layer 4b2).

[0267] Layer 4b 1:

[0268] [Tables4] Material Nature % wet % in cooked film Solvent DEMINERALIZED WATER 33.63 0.00 Solvent PROPIONAMIDE 25.22 0.00 Thermoplastic polymer PES 21.02 79.52 Wetting agent Fatty alcohol polyglycol ether 0.59 0.09 Acrylic thickener 50% acrylic polymer solution in water 6.23 2.62 Buffering agent Amino alcohol 1.19 0.00 Pigment Carbon black 4.70 5.57 Antifoam Mineral oil 1.41 0.27 Reinforcing filler Colloidal silica 4.14 4.75 Reinforcing filler Mica 1.40 5.35 Pigment Glitter 0.48 1.83 100.00 100

[0269] Layer 4b2: Material Nature % wet % in cooked film Silicone resin Methyl or methyl-phenyl silicone resin 21.62 51.39 Solvent Alcohol Glycol ether 21.62 0.00 Thickener Hydrogenated castor oil 0.72 1.66 Reinforcing filler Mica 1.08 2.73 Reinforcing filler Pyrogenic silica 1.44 3.65 Pigment Carbon black 4.32 3.39 Wetting agent Fatty alcohol polyglycol ether 1.08 0.11 Solvent DEMINERALIZED WATER 11.19 0.00 Solvent PROPIONAMIDE 8.40 0.00 Thermoplastic polymer PES 8.40 21.02 Acrylic thickener 50% acrylic polymer solution in water 0.56 0.16 Buffering agent Amino alcohol 0.09 0.00 Spreading Agent Anionic Ester in Ethanol / Water 1.44 1.28 Surface Tension Agent Aqueous Dispersion of Polydimethylsiloxane Gum 0.72 0.97 Solvent Alcohol Propylene Glycol 6.49 0.00 Reinforcing Filler Colloidal Alumina 7.21 10.92 Reinforcing Filler Colloidal Silica 3.60 2.73 100.00 100

[0271] The compositions of the 4c ​​finishing layers deposited by screen printing are as described below (layers 4c 1 to 4c4): Top coat (4c)

[0272] Layer 4cl: Material Nature %humid e % in cooked film Solvent DEMINERALIZED WATER 39.4 0.00 Solvent PROPIONAMIDE 29.55 0.00 Thermoplastic polymer PES 24.62 91.15 Wetting agent Fatty alcohol polyglycol ether 0.69 0.10 Acrylic thickener 50% acrylic polymer solution in water 3.44 1.42 Buffering agent Amino alcohol 0.3 0.00 Silicone oil A 2.00 7.33 100 100

[0274] Layer 4c2: Material Nature % wet % in cooked film Silicone resin Methyl or methyl-phenyl silicone resin 30.00 70.62 Solvent Alcohol Glycol ether 39.60 0.00 Reinforcing filler Pyrogenic silica 1.00 2.50 Thickener Hydrogenated castor oil 1.70 3.87 Wetting agent Fatty alcohol polyglycol ether 1.65 0.17 Solvent DEMINERALIZED WATER 8.54 0.00 Solvent PROPIONAMIDE 6.41 0.00 Thermoplastic polymer PES 6.41 15.89 Acrylic thickener 50% acrylic polymer solution in water 0.43 0.12 Buffering agent Amino alcohol 0.06 0.00 Spreading agent Anionic ester in ethanol / water 1.50 1.31 surface tension Aqueous dispersion of poly-dimethylsiloxane gum 1.00 1.33 Silicone oil B 1.00 2.45 Silicone oil A 0.50 1.23 Glitter pigment 0.20 0.50 100.00 100

[0276] Layer 4c3: Material Nature % wet % in cooked film Silicone resin Methyl or methyl-phenyl silicone resin 7.1 23.44 Solvent Alcohol Glycol ether 7.1 0.00 Thickener Hydrogenated castor oil 0.1 0.32 Reinforcing filler Pyrogenic silica 0.2 0.70 Wetting agent Fatty alcohol polyglycol ether 0.4 0.06 Solvent Alcohol Propylene glycol 12.82 0.00 Spreading agent Anionic ester in ethanol / water 0.35 0.43 Antifoam Mineral oil 0.7 0.12 Solvent DEMINERALIZED WATER 27.3 0.00 Solvent PROPIONAMIDE 20.48 0.00 Thermoplastic polymer PES 20.48 71.21 Wetting agent Fatty alcohol polyglycol ether 0.48 0.07 Acrylic Thickener 50% Acrylic Polymer Solution in Water 1.39 0.54 Buffering Agent Amino Alcohol 0.2 0.00 Silicone Oil A 0.7 2.41 Pigment Glitter 0.2 0.70 100 100

[0278] Layer 4c4: Material Nature % wet % in cooked film Silicone resin Methyl or methyl-phenyl silicone resin 30.00 84.33 Solvent Alcohol Glycol ether 41.70 0.00 Thickener Hydrogenated castor oil 1.60 4.35 Reinforcing filler Pyrogenic silica 1.00 2.99 Wetting agent Fatty alcohol polyglycol ether 1.50 0.18 Solvent Alcohol Propylene glycol 20.00 0.00 Spreading agent Anionic ester in ethanol / water 1.50 1.57 Surface tension agent Aqueous dispersion of polydimethylsiloxane gum 1.00 1.58 Silicone oil B 1.00 2.93 Silicone oil A 0.50 1.47 Pigment Glitter 0.20 0.60 100.00 100

[0280] Examples of construction / architecture of heating elements according to the invention:

[0281] [Tables10] 1 2 3 Base coat al a2 al Intermediate coat bl b2 bl Top coat cl c2 c3

Claims

Claims

1. Coated cooking element (1) for a cooking article or electrical cooking appliance, comprising a metal substrate (2) coated on at least one face (2a) with a coating (3) intended to form a cooking face free of fluorocarbon resin and coated on at least the other face (2b) with a coating (4) comprising at least the following layers and in this order starting from the metal substrate (2): - (4a) primer layer comprising polyethersulfone (PES), - (4b) optionally, one or more intermediate layer(s) comprising polyethersulfone (PES) or a mixture of polyethersulfone (PES) and one or more silicone resins, - (4c) finishing layer comprising polyethersulfone (PES) or one or more silicone resins or a mixture of polyethersulfone (PES) and one or more silicone resins.

2. Coated cooking element (1) according to claim 1, characterized in that the PES content increases from the primer layer (4a) to the finishing layer (4c).

3. Coated cooking element (1) according to claim 2, characterized in that the PES content of the primer layer (4a) represents from 50% to less than 75% by weight of the primer layer (4a).

4. Coated cooking element (1) according to any one of the preceding claims, characterized in that the PES content of the intermediate layer(s) (4b) represents from 75% to less than 85% by weight of said layer(s) when it is / are present.

5. Coated cooking element (1) according to any one of the preceding claims, characterized in that the PES content of the finishing layer (4c) represents from 85% to 98% by weight of the finishing layer (4c).

6. Coated cooking element (1) according to any one of the preceding claims, characterized in that the thickness of each of the coating layers (4a), (4b) and (4c) is from 5 pm to 15 pm.

7. Coated cooking element (1) according to claim 1, characterized in that the layer (4c) is made up of: - a silicone elastomer obtained from at least one organopolysiloxane carrying reactive vinyl functions (-CH=CH2), at least one other organopolysiloxane carrying reactive silyl hydride functions (Si-H), preferably in the presence of a metal catalyst; and optionally: - one or more thermoplastics, and / or - one or more additive(s), and / or - one or more coloring agents when at least one layer (4b) is present.

8. Method for manufacturing a culinary article or electrical cooking appliance comprising a cooking element coated (1) with a coating (4) according to any one of the preceding claims, characterized by the following steps: a) a step of providing a metal substrate (2) in the form of a substantially flat metal substrate comprising two opposite faces; b) optionally, a step of treating at least one face (2a) of the metal substrate (2), to obtain a treated face (2a) promoting the adhesion of a primer layer (4a) to the support (2); c) a step of applying the layers (4a), optionally (4b), and (4c) of the coating (4); d) optionally a drying step between 50°C and 150°C after application of said layers; e) a step of baking the element obtained in step c) or d) at a temperature between 250°C and 420°C.f) a step of shaping the element obtained to give it the shape of a support (2) of convex or hollow shape defining a concave inner face (21) and a convex outer face (22).

9. Culinary article or electrical cooking appliance comprising a coated cooking element (1) according to any one of claims 1 to 7 or capable of being obtained according to claim 8 characterized in that the layer (4c) is intended to be placed in contact with a heating source.

10. Culinary article (100) according to claim 9, chosen from the group consisting of saucepan, frying pan, skillets or pots for fondue or raclette, stewpan, wok, sauté pan, crepe pan, grill, griddle, pot, casserole dish, cooker or bread machine bowl, culinary mold, molds and plates for baking, barbecue plates and grills, preparation bowls.

11. Electric cooking appliance (200) according to claim 9, chosen from the group consisting of electric crepe maker, electric raclette appliance, electric fondue appliance, electric grill, electric griddle, electric cooker, bread maker, electric pressure cooker, waffle irons, rice cookers and jam makers.

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