Substrate comprising surface coated with oil repellent and method of oil repellent coating such substrate

Abstract

The invention relates to a substrate comprising a surface at least partially coated with an oil repellent, characterized in that the oil repellent comprises at least one compound in the form of a copolymer comprising M units and N units linked by covalent bonds on its backbone, where M, N, R1 and R2 are the same or different and are H, C1-C10 alkyl or C2-C10 alkenyl; x and Y are the same or different and are spacer arms formed by heteroatoms or linear or branched hydrocarbon chains containing at least one heteroatom and at least one carbon atom; b is the same or different and is a polyether group; l is the same or different and is a halogenated C1-C6 carbon group or a halogenated ether group shown in the formula (I), and in the formula (I), Q is a halogen atom; p, identical or different, is a linear or branched C1-C10 alkyl group or C2-C10 alkenyl group comprising at least one halogen atom; p is selected from 1 to 4; and n is selected from 1 to 20, and wherein the copolymer is water soluble. The invention also relates to a method for oil-proof coating of such a substrate, and to a timepiece or jewelry comprising an assembly containing such a substrate.

Description

Technical Field

[0001] The present invention relates to a substrate comprising a surface at least partially coated with an epilae agent. The invention also relates to a method for epilae coating such a substrate. Background Art

[0002] There are various methods for modifying the surface state of substrates by treating them with suitable agents, thereby specifically improving certain surface properties. For example, in the mechanical field, particularly in the watchmaking field, and in the jewelry field, oil-repellent coatings are commonly used to coat the surfaces of parts or components with oil in order to control and reduce the surface tension during use. More specifically, oil-repellent coatings are designed to create a hydrophobic and oleophobic surface, confining lubricants to predetermined locations on the treated surface, thereby preventing the spread of oil or lubricants onto components of the watch or jewelry.

[0003] However, the materials currently used for oil-repellent coatings have many disadvantages. For example, of Oil repellents such as ES / BS or 3M™'s Novec™ series have poor resistance to watch cleaning.

[0004] Patent application US2012 / 0088099 proposes using an oil-repellent with catechol functional groups at the end of its chain, partially addressing this issue. While these catechol functional groups can firmly adhere to certain substrates, they do not improve the watch cleaning resistance of substrates such as gold and steel, which are common in the watch and jewelry industries. Consequently, the use of known oil-repellents is generally limited to certain materials, requiring users to prepare different types of oil-repellents based on the properties of the surface being treated.

[0005] For example, patent application WO 2012 / 085130 describes a solution to this problem. This solution involves using a mixture of different compounds (thiols and bisphosphonates) as an oil-repellent composition. The synergistic effect of these compounds promotes adhesion of the oil-repellent agent to the substrate. However, the synthesis of each of these compounds requires at least four steps, making the overall oil-repellent composition synthesis process lengthy and complex.

[0006] For example, patents EP 3 070 133 and EP 3 070 152 describe another solution. Patent EP 3 070 133 describes an oil repellent comprising a statistical copolymer comprising fluorinated units, anchor units and optionally additional hydrocarbon chains. Patent EP 3 070 152 describes an oil repellent comprising a block copolymer comprising fluorinated units, anchor units and optionally additional hydrocarbon chains. Specifically, -C5F 11 and-C6F13 Fluorinated unit.

[0007] However, perfluorohexanoic acid (PFHxA, CAS 307-24-4), its salts, and related substances are subject to general regulatory scrutiny for environmental reasons. Furthermore, these repellents are typically applied to the substrate surface using a solvent-based repellent coating bath containing the repellent. Furthermore, the solvents used are often fluorinated, making the repellent coating process polluting. SUMMARY OF THE INVENTION

[0008] The present invention is particularly intended to remedy the various drawbacks of known oil-repellent agents and oil-repellent coating methods.

[0009] More specifically, one of the objects of the present invention is to provide an oil repellent that is not subject to general regulatory scrutiny for environmental reasons. The present invention also aims to provide an oil repellent that can be applied by an environmentally friendly method, more specifically a method that significantly reduces or even completely eliminates the use of polluting solvents (e.g., fluorinated solvents).

[0010] The present invention also aims to provide an oil repellent having higher washing resistance than known oil repellents. The present invention also aims to provide a universal oil repellent that can be used for any type of material.

[0011] The present invention also aims to provide an environmentally friendly oil-repellent coating method that does not require the use of solvents, more specifically, polluting fluorinated solvents. The present invention also aims to provide a cost-effective oil-repellent coating method that does not require the use of large amounts of expensive fluorinated solvents.

[0012] The present invention also aims to provide an oil-proofing agent and an oil-proofing coating method, which can accurately measure the concentration of the oil-proofing agent as it changes over time, thereby improving the stability of the entire oil-proofing coating process.

[0013] To this end, a first aspect of the present invention relates to a substrate comprising a surface at least partially coated with an oil repellent according to the appended claims.

[0014] According to the present invention, the oil repellent comprises at least one compound in the form of a copolymer comprising M units and N units. These M units and N units are linked via covalent bonds on their main chains.

[0015] According to the present invention, M is in R1, the same or different, is H, C1-C 10 Alkyl, C2-C 10 Alkenyl, preferably H or CH3; Y, which is the same or different, is a spacer arm formed by a heteroatom or a straight or branched hydrocarbon chain containing at least one heteroatom and at least one carbon atom; B, which are the same or different, are polyether groups.

[0016] Advantageously, Y, identical or different, is selected from C1-C 20 Ester groups, amide groups and styrene derivative groups. Optionally, Y, being the same or different, comprises at least one heteroatom.

[0017] Advantageously, B, identical or different, is -((CH2) α O) β -R3 group, wherein R3 is H, C1-C 10 Alkyl, C2-C 10 Alkenyl, preferably H or CH3, α is selected between 1 and 6, preferably between 2 and 3, and β is selected between 1 and 30, preferably between 2 and 20, for example, between 8 and 10 or between 18 and 20.

[0018] According to the present invention, N is in R2, the same or different, is H, C1-C 10 Alkyl, C2-C 10 Alkenyl, preferably H or CH3; X, which is the same or different, is a spacer arm formed by a heteroatom or a linear or branched hydrocarbon chain containing at least one heteroatom and at least one carbon atom; L, the same or different, is a halogenated C1-C6 carbon group or a halogenated ether group represented by formula (I): in Q is a halogen atom; P, the same or different, is a straight or branched C1-C 10 Alkyl or C2-C 10 alkenyl; p is selected between 1 and 4, preferably between 2 and 3; and n is selected from 1 to 20, preferably from 1 to 10.

[0019] Advantageously, X, identical or different, is selected from C1-C 20 Ester groups, amide groups and styrene derivative groups. Optionally, X, identical or different, contains at least one heteroatom.

[0020] Advantageously, L is an at least partially fluorinated (e.g., fully fluorinated) C1-C6 carbon group. Alternatively, also advantageously, L is an at least partially fluorinated (e.g., fully fluorinated) ether group. As used in this disclosure, the term "fully fluorinated" refers to a group in which each hydrogen atom is replaced by a fluorine atom.

[0021] It is noted that the copolymer may contain different L groups, for example, a blend of at least partially halogenated C1-C6 carbon groups and halogenated ether groups according to formula (I).

[0022] Advantageously, the copolymer is a statistical copolymer. Advantageously, the M units and the N units are randomly distributed. Advantageously, the copolymer is a statistical copolymer and the M units and the N units are randomly distributed.

[0023] Alternatively, also advantageously, the copolymer is a block copolymer. Advantageously, the block copolymer comprises at least one M unit block covalently linked to its main chain, and at least one N unit block covalently linked to its main chain. Advantageously, these blocks are covalently linked together in a linear sequence via the main chain.

[0024] Advantageously, the ratio of M units to N units is between 1:10 and 10:1, preferably between 1:5 and 5:1.

[0025] More specifically, when B is -((CH2) α O) β When the α-R3 group is present, the inventors have discovered that the optimal ratio of M units to N units depends on the β value. "Optimal ratio of M units to N units" should be understood as the ratio of M units to N units that achieves the best oil-repellency. Excellent oil-repellency results from, but is not limited to, low surface tension values, high water droplet inclination angle values (in any case greater than 85°), and / or excellent resistance to cleaning, particularly resistance to watch cleaning.

[0026] For example, when β is equal to a value between 1 and 10, preferably between 5 and 10, more preferably between 8 and 10, for example 9, the optimal ratio of M units to N units is between 1:1 and 2:1, more specifically between 1:1 and 3:2, for example between 1:1 and 11:9, or between 1:1 and 10:9. For example, when β is equal to a value between 11 and 30, preferably between 12 and 20, more preferably between 18 and 20, for example 19, the optimal ratio of M units to N units is between 1:5 and 3:5, more specifically between 2:5 and 1:2.

[0027] The inventors have unexpectedly discovered that the oil repellent agent of the present invention is at least partially soluble in water, preferably completely soluble in water. More specifically, the copolymer is at least partially soluble in water, preferably completely soluble in water. The inventors believe that this excellent water solubility is due to, but not limited to, the specific composition of the copolymer. More specifically, the inventors believe that the ratio of M units to N units renders the copolymer, and advantageously the oil repellent agent, soluble in water. Therefore, the copolymer and oil repellent agent of the present invention enable the use of aqueous oil repellent coating methods, eliminating the need for polluting organic solvents.

[0028] Advantageously, and optionally, the copolymer according to the present invention further comprises K units. Advantageously, the K units are covalently bonded to the M units and the N units on the copolymer backbone. Advantageously, K is in R4, the same or different, is H, C1-C 10 Alkyl or C2-C 10 Alkenyl, preferably H or CH3; W, the same or different, is a spacer arm formed from a heteroatom or a straight or branched hydrocarbon chain containing at least one heteroatom and at least one carbon atom; and A, identical or different, forms an anchoring group on the substrate.

[0029] Advantageously, W, identical or different, is selected from C1-C 20 Ester groups, amide groups and styrene derivative groups. Optionally, W, being the same or different, contains at least one heteroatom.

[0030] Advantageously, A is selected from glycidyl, thiol, thioether, thioester, sulfide, thioamide, silanol, alkoxysilane, silane halide, hydroxyl, phosphate, protected or unprotected phosphonic acid, protected or unprotected phosphonate, amine, ammonium, nitrogen heterocycle, carboxylic acid, anhydride and catechol.

[0031] Advantageously, when the copolymer according to the invention comprises K units and β is equal to a value between 8 and 10, the copolymer comprises from 5% to 20%, preferably from 7% to 15%, of K units, from 30% to 65%, preferably from 35% to 60%, of M units and from 25% to 60%, preferably from 30% to 55%, of N units, these percentages being expressed relative to the total number of units in the copolymer.

[0032] Advantageously, when the copolymer according to the invention comprises K units and β is equal to a value between 18 and 20, the copolymer comprises from 5% to 20%, preferably from 7% to 15%, of K units, from 15% to 45%, preferably from 25% to 35%, of M units and from 50% to 75%, preferably from 55% to 65%, of N units, these percentages being expressed relative to the total number of units in the copolymer.

[0033] Advantageously and optionally, the copolymer according to the present invention further comprises V units. Advantageously, the V units are covalently bonded to the M units and the N units on the copolymer backbone. Advantageously, V is in R5, the same or different, is H, C1-C 10 Alkyl, C2-C 10 Alkenyl, preferably H or CH3; Z, identical or different, is a spacer arm formed by a heteroatom or a linear or branched hydrocarbon chain containing at least one heteroatom and at least one carbon atom; and T, which is the same or different, is a tracer group used to determine the concentration of the oil repellent agent in the oil repellent coating bath.

[0034] Advantageously, T, identical or different, is a UV absorbing group or a fluorophore.

[0035] Advantageously, when the copolymer according to the invention comprises V units, it comprises from 0.1% to 20% of K units, preferably from 0.5% to 15% and more preferably from 1% to 10%, these percentages being expressed relative to the total number of units in the copolymer.

[0036] Advantageously, the surface of the substrate coated at least in part with the oil repellent is made of a material selected from the group consisting of optionally doped metals, metal oxides, metal nitrides, metal carbides, optionally doped metalloids, metalloid oxides, metalloid nitrides, metalloid carbides, alloys comprising at least one metal element, polymers, sapphire, ruby, diamond-like carbon (DLC), and combinations of two or more thereof.

[0037] A second aspect of the present invention relates to a method for oil-repellent coating of at least part of the surface of a substrate according to the appended claims.

[0038] The oil-repellent coating method according to the present invention comprises preparing an oil-repellent agent comprising at least one water-soluble copolymer as defined above. Optionally, the oil-repellent coating method further comprises preparing a substrate surface. The oil-repellent coating method further comprises contacting the substrate surface with the oil-repellent agent.

[0039] Advantageously, the oil-proofing agent is prepared by copolymerizing a monomer capable of forming an M unit with a monomer capable of forming an N unit (the preparation of the oil-proofing agent is completed). Advantageously, the M unit and the N unit are as described above. Advantageously, the monomer is selected from acrylate monomers, methacrylate monomers, acrylamide monomers, methacrylamide monomers, vinyl monomers, and styrene monomers.

[0040] According to one embodiment of the oil-repellent coating method, the oil-repellent agent is prepared by preparing an oil-repellent coating bath containing the oil-repellent agent. Advantageously, the oil-repellent coating bath is an aqueous oil-repellent coating bath comprising the oil-repellent agent dissolved in water. Subsequently, at least a portion of the surface of the substrate is contacted with the oil-repellent agent in the aqueous oil-repellent coating bath, for example, by immersing the substrate in the aqueous oil-repellent coating bath.

[0041] This method of preparing the oil repellent agent is particularly suitable when the oil repellent agent comprises at least one copolymer, and the copolymer further comprises V units covalently bonded to M units and N units in its backbone. Advantageously, the V units are as described above. The presence of the V units, and particularly the tracer group, advantageously and optionally enables testing the concentration of the oil repellent agent in the aqueous oil repellent coating bath prior to contact. Advantageously, this testing is performed using the tracer group. Optionally, after testing the concentration of the oil repellent agent, the concentration of the oil repellent agent in the aqueous oil repellent coating bath can be readjusted.

[0042] According to another embodiment of the oil-repellent coating method, a substrate and an oil-repellent agent are placed in a container at ambient pressure, which is then sealed, allowing the surface of the substrate to contact the oil-repellent agent. CO2 at a pressure of 25 to 74 bar (preferably 45 to 70 bar) and a temperature of 10°C to 80°C (preferably 15°C to 50°C) is then introduced into the sealed container. The pressure in the container is then reduced, and the oil-repellent-coated substrate is removed from the container.

[0043] A third aspect of the present invention relates to the use of a copolymer comprising M units and N units covalently bonded through their molecular chains as an oil repellent for at least a portion of the surface of a substrate. The M units and N units are as described above. The copolymer is water-soluble.

[0044] The invention also relates to a timepiece or jewellery comprising a component comprising a substrate according to the first aspect of the invention.

[0045] One advantage of the oil repellents of the present invention is that they are not subject to typical regulatory scrutiny for environmental reasons, despite their high oil repellency. Another advantage is that the copolymers contained in the oil repellents are water-soluble, which makes fluorinated solvents redundant and provides a more environmentally friendly and generally more economical alternative. Another advantage is that the oil repellents of the present invention have excellent resistance to cleaning, especially watch cleaning. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The objects, advantages and features of the present invention are illustrated by the following drawings, which are not limiting, in which: - Figure 1 The structure of the oil-proof copolymer according to the present invention is shown; - Figure 2The contact angles measured on various substrates coated with the oil repellent according to the present invention are shown; - Figure 3 Shown is a surface coated with reference C6F 13 Contact angles of oil repellents measured on various substrates; - Figure 4 Shows the contact angles measured on various substrates coated with competing oil repellents;

[0047] According to the present invention, the substrate comprises a surface, at least a portion of which is coated with an oil repellent. Advantageously, at least the surface of the substrate, and optionally the entire substrate, is made of a material selected from the group consisting of optionally doped metals, metal oxides, metal nitrides, metal carbides, optionally doped metalloids, metalloid oxides, metalloid nitrides, metalloid carbides, alloys comprising at least one metallic element, polymers, sapphire, ruby, diamond-like carbon (DLC), and combinations of two or more thereof.

[0048] Preferably, the metal is copper, nickel, beryllium, iron, cobalt, titanium, zirconium, tungsten, silver, gold, platinum, chromium, manganese, magnesium, molybdenum, rhodium, palladium or zinc.

[0049] Non-limiting examples of doping metals include nickel phosphorus (NiP) and boron doped platinum.

[0050] Preferably, the metalloid is boron or silicon.

[0051] Non-limiting examples of alloys containing at least one metal element include brass, aluminum brass, and steel. Non-limiting examples of steel include carbon steel and stainless steel. Non-limiting examples of carbon steel include 15P (also known as S15P), CK75, and 20AP.

[0052] Advantageously, in the present invention, the substrate is a substrate of a timepiece component or jewelry.

[0053] Advantageously, the X groups are identical or different and are selected from C1-C 20 Ester group, preferably C2-C 10 Ester groups, more preferably C2-C6 ester groups, even more preferably C2-C5 ester groups, preferably alkyl ester groups, preferably linear alkyl ester groups, amide groups and styrene derivative groups.

[0054] Advantageously, the Y groups are identical or different and are selected from C1-C 20 Ester group, preferably C2-C 10 Ester groups, more preferably C2-C6 ester groups, even more preferably C2-C5 ester groups, preferably alkyl ester groups, preferably linear alkyl ester groups, amide groups and styrene derivative groups.

[0055] The functional groups B are hydrophilic groups. Advantageously, they determine the water solubility of the copolymer. Advantageously, the functional groups B contain 1 to 30 ether groups, preferably 2 to 20 ether groups. In other words, the functional groups B are polyethers.

[0056] Advantageously, the ether group contains 1 to 6 CH2 groups, preferably 2 to 3 CH2 groups. For example, when α is 2, the ether group is of the ethyl ether type (CH2CH2O). For example, when α is 4, the ether group is of the butyl ether type (CH2CH2CH2CH2O).

[0057] The functional group L is responsible for producing the oil-proofing effect. They contain at least one halogen atom. Preferably, the halogen atoms are identical or different and are fluorine atoms, iodine atoms, bromine atoms or chlorine atoms. Preferably, the halogen atoms are fluorine atoms. If the L group contains multiple halogen atoms, these atoms can be identical or different. Advantageously, all halogen atoms in the L group are fluorine atoms.

[0058] When the functional group L is a halogenated C1-C6 carbon group, the group is preferably partially or fully halogenated. Advantageously, when L is a halogenated C1-C6 carbon group, L is at least partially fluorinated, preferably fully fluorinated. When L is a halogenated C1-C6 carbon group, the terminal group of L may further contain a hydrogen atom.

[0059] When the functional group L is a halogenated ether group, L further comprises a P group. The P groups, which are identical or different, are advantageously C1-C 10 Alkyl, C2-C 10 Alkyl or C2-C 10 Alkynyl. The P group advantageously contains at least one halogen atom. Advantageously, the halogen atoms, identical or different, are fluorine atoms, iodine atoms, bromine atoms or chlorine atoms. Preferably, the halogen atom is a fluorine atom. The P group may be straight-chain or branched.

[0060] Advantageously, the P group is C1-C 10 Perfluoroalkyl, preferably C1-C6 perfluoroalkyl, such as C1-C4 perfluoroalkyl, such as CF3, C2F5, C3F7 or C4F9.

[0061] Advantageously and alternatively, the P group is C2-C 10 Perfluoroalkenyl, preferably C2-C6 perfluoroalkenyl, such as C2-C4 perfluoroalkenyl, such as C2F3, C3F5 and C4F7.

[0062] Advantageously and alternatively, the P group is C2-C 10 Perfluoroalkynyl, preferably C2-C6 perfluoroalkynyl, such as C2-C4 perfluoroalkynyl, such as C2F, C3F3 and C4F5.

[0063] Advantageously, in the functional group L, p is selected from 1 to 4, preferably 2 to 3.

[0064] Advantageously, in the functional group L, n is selected from 1 to 20, such as 1 to 16, preferably 1 to 10, such as 2 to 8.

[0065] A preferred functional group L in the present invention is C6F 13 Structural representation.

[0066] Another preferred functional group L in the present invention is (CF(CF3)OCF2) n The structure of CF2CF3 is represented, that is, Q is a fluorine atom (F), P is CF3, and p is 2. More specifically, the preferred structure of the L group is (CF(CF3)OCF2)5CF2CF3, that is, Q is a fluorine atom (F), P is CF3, p is 2, and n is 5.

[0067] One of the copolymers preferably used in the present invention has the following structure (II)

[0068] In other words, in the copolymer (II), X is C(O)O(CH2)2; Y is C(O)O; L is (CF2)5CF3; α is 2, which means that B is ((CH2)2O) β R3. Preferably, in the copolymer represented by structure (II), R1, R2 and R3 are the same or different and are H or CH3.

[0069] A specific example (but not limited to) of the copolymer shown in structure (II) is the following copolymer: wherein R1 is CH3, R2 is CH3, R3 is CH3, when the average value of β in the copolymer is between 8 and 10, the m / p ratio is between 1:1 and 11:9; when the average value of β in the copolymer is between 18 and 20, the m / p ratio is 3:7.

[0070] Optionally, the copolymer may further comprise at least one K unit, wherein K is as described above. Advantageously, when the copolymer comprises at least one K unit, the K unit is linked to the M unit and the N unit on its main chain via a covalent bond.

[0071] Advantageously, the W groups, identical or different, are selected from C1-C 20 Ester group, preferably C2-C 10 Ester groups, more preferably C2-C6 ester groups, even more preferably C2-C5 ester groups, preferably alkyl ester groups, preferably linear alkyl ester groups, amide groups and styrene derivative groups.

[0072] The functional group A can react with the surface of the substrate to be coated with the oil repellent agent, thereby forming an anchoring group for the oil repellent agent on the substrate surface. Advantageously, the A group can also be located at the end of the copolymer.

[0073] Optionally, the copolymer may further comprise at least one U unit, wherein U is in R6, the same or different, is H, C1-C 10 Alkyl or C2-C 10 alkenyl, preferably H or CH3; and R7, identical or different, is H, CH3, a hydrocarbon chain which may contain at least one linear or branched, saturated or unsaturated heteroatom, said hydrocarbon chain containing at least 2 carbon atoms.

[0074] Advantageously, when the copolymer comprises at least one U unit, the U unit, the M unit and the N unit are linked on its main chain by covalent bonds.

[0075] Advantageously, the R7 functional group can modify the properties of the oil repellent and / or add other functionalities. For example, R7 can be an alkyl chain for modifying the resulting contact angle, or a chain capable of forming crosslinking points in an additional crosslinking step.

[0076] Optionally, the copolymer may further comprise at least one V unit, wherein V is as described above. Advantageously, when the copolymer comprises at least one V unit, the V unit is linked to the M unit and the N unit on its main chain via covalent bonds.

[0077] Advantageously, the Z groups are identical or different and are selected from C1-C 20 Ester group, preferably C2-C 10 Ester groups, more preferably C2-C6 ester groups, even more preferably C2-C5 ester groups, preferably alkyl ester groups, preferably linear alkyl ester groups, amide groups and styrene derivative groups.

[0078] Advantageously, the T group allows the concentration of the copolymer to be determined, for example, by spectroscopic methods.

[0079] Advantageously, T, identical or different, is a UV-absorbing group derived from a compound selected from benzotriazoles, triazines, benzophenones (especially benzophenones, acetophenones, hydroxyalkylphenones, hydroxyarylphenones, aminoalkylphenones and anthraquinones) and acylphosphine oxides.

[0080] Advantageously, T, identical or different, is a fluorophore group derived from a compound selected from fluorescein, naphthyl, anthracene, coumarin, rhodamine and fluorobenzoate.

[0081] Advantageously, the copolymer comprises from 5 to 500 units, preferably from 10 to 350 units.

[0082] The copolymers may be statistical copolymers or block copolymers.

[0083] Advantageously, when the copolymer is a statistical copolymer, the M, N units, the optional K units, the optional V units and the optional U units are randomly distributed. In other words, these units are linked to each other in a statistical manner via their backbone.

[0084] Advantageously, when the copolymer is a block copolymer, the copolymer comprises at least one M unit block connected by covalent bonds on its main chain, and at least one N unit block connected by covalent bonds on its main chain. Preferably, the block copolymer comprises a single M unit block and / or a single N unit block.

[0085] Optionally, the block copolymer further comprises at least one K unit block covalently linked to its backbone.Preferably and optionally, the block copolymer comprises a single K unit block.

[0086] Optionally, the block copolymer further comprises at least one V unit block connected via a covalent bond on its backbone.Preferably and optionally, the block copolymer comprises a single V unit block.

[0087] Optionally, at least one of the M unit block, the N unit block, the optional K unit block and the optional V unit block comprises at least one U unit connected by covalent bonds on its main chain. Advantageously, these blocks are covalently linked together with a straight chain sequence on its main chain. If the block copolymer also comprises at least one U unit, at least one of the M unit block, the N unit block, the optional K unit block and the optional V unit block comprises at least one U unit, and the number of U units in the M unit block can be different from the number of U units in the N unit block, the number of U units in the K unit block and the number of U units in the V unit block (if the latter (K and V) is included in the block copolymer).

[0088] Preferably, the U units are introduced and distributed within the blocks composed of N units, for example by statistically copolymerizing the U units with the N units to form a single block composed mainly of N units and assimilating it with the N unit blocks.

[0089] The present invention also relates to a method for coating at least a portion of a substrate surface with oil repellent, comprising preparing an oil repellent agent, optionally preparing a substrate surface, and contacting the substrate surface with the oil repellent agent.

[0090] Advantageously, the preparation of the oil repellent comprises copolymerizing a monomer capable of forming an M unit with a monomer capable of forming an N unit, optionally a monomer capable of forming at least one K unit, optionally a monomer capable of forming at least one V unit and optionally a monomer capable of forming at least one U unit.

[0091] Advantageously, the monomers are chosen from acrylate, methacrylate, acrylamide, methacrylamide, vinyl, diene, styrene and olefin monomers.

[0092] Particularly preferred monomers for forming the V unit containing the tracer group T are selected from the group consisting of 2-H-benzotriazol-2-yl-hydroxyphenylethyl methacrylate, 2-(2H-benzotriazol-2-yl)-4-methyl-6-(2-propenyl)phenol, 2-(4-benzoyl-3-hydroxyphenoxy)ethyl acrylate, 4-allyloxy-2-hydroxybenzophenone, 2-naphthyl(meth)acrylate, fluorescein O-(meth)acrylate, 9-anthrylmethyl(meth)acrylate, ethidium bromide-N,N'-bisacrylamide, N-(1-naphthyl)-N-phenylmethacrylamide, and 7-[4-(trifluoromethyl)coumarin]methacrylamide. Such monomers are commercially available and polymerizable.

[0093] More preferably, the monomers used to form the V unit containing the tracer group T are selected from the group consisting of 2-H-benzotriazol-2-yl-hydroxyphenylethyl methacrylate, 2-(2H-benzotriazol-2-yl)-4-methyl-6-(2-propenyl)phenol, 2-(4-benzoyl-3-hydroxyphenoxy)ethyl acrylate, and 4-allyloxy-2-hydroxybenzophenone. These monomers contain tracer groups that can be monitored by UV-visible spectroscopy, which is easier to establish in an industrial environment than fluorescence spectroscopy.

[0094] Polymerization techniques include those known to those skilled in the art. Optionally, the copolymerization is carried out in the presence of an initiator system comprising an initiator such as, but not limited to, azobisisobutyronitrile (AIBN). Optionally, the copolymerization is carried out at an elevated temperature.

[0095] The copolymer used in the present invention can be prepared in the form of a powder or a viscous liquid.

[0096] A particularly suitable polymerization process for preparing statistical copolymers is free radical copolymerization in solution or emulsion. Advantageously, the free radical copolymerization is a free radical copolymerization or a controlled radical copolymerization, preferably a controlled radical copolymerization.

[0097] A particularly suitable polymerization process for preparing block copolymers is the continuous controlled free-radical copolymerization of the following monomers: - a monomer capable of forming at least one block of M units, and optionally a monomer capable of forming at least one U unit; - monomers capable of forming at least one block of N units, and optionally monomers capable of forming at least one U unit, wherein U is identical or different; - optionally monomers capable of forming at least one block of K units, and optionally monomers capable of forming at least one U unit, wherein U is identical or different; - optionally monomers capable of forming at least one block of V units, and optionally monomers capable of forming at least one U unit, wherein U are identical or different;

[0098] According to the first copolymerization mode, the copolymer can be prepared in a single step by copolymerization (preferably free radical copolymerization) of a monomer with a YB side chain with a monomer with an XL side chain, optionally a monomer with a WA side chain, optionally a monomer with a ZT side chain and optionally a monomer with an R7 side chain.

[0099] According to another copolymerization mode, the copolymer can be obtained by copolymerizing (preferably free radical copolymerization) a monomer with sufficient Y side chains with a monomer with sufficient X side chains, optionally a monomer with sufficient W side chains, optionally a monomer with sufficient Z side chains, and optionally a monomer with a side chain for carrying R7, and then modifying the side chains, for example, by "click chemistry", to introduce the functional groups B, L, A (optional), T group (optional) and R7 group (optional).

[0100] Optional preparation of the substrate surface may include cleaning and / or rinsing the surface to be coated with the oil repellent. Such cleaning or rinsing may be performed using methods known to those skilled in the art. For example, particularly when the substrate is a watch component, cleaning may include cleaning according to standard watchmaking methods.

[0101] Alternatively, the preparation of the substrate surface may comprise a CO2 treatment at a temperature of 10°C to 80°C and a pressure of 25 bar to 250 bar, for example for 1 minute to 60 minutes. Advantageously, this treatment removes particulate dust and degreases the surface.

[0102] Advantageously, one or more copolymers are dissolved in the aqueous solution. Advantageously, based on the cumulative volume of the aqueous solution before adding one or more polymers, the aqueous solution comprises 0 volume % to 15 volume % of a non-halogenated organic solvent, preferably 0 volume % to 10 volume %. Therefore, when the aqueous solution does not contain a non-halogenated organic solvent (0 volume %), the aqueous solution is water. Advantageously, one or more copolymers are dissolved in water. Known addition of a non-halogenated organic solvent helps polymer to be soluble in water.

[0103] Non-limiting examples of non-halogenated organic solvents include alcohols such as methanol, ethanol, n-butanol, and isopropanol; ethers; esters; ketones such as acetone and butanone; amines; and alkanes such as pentane, hexane, and heptane.

[0104] Advantageously, the aqueous solution does not contain any halogenated solvents. Advantageously, the oil repellent solution does not contain any halogenated solvents.

[0105] Advantageously, one or more copolymers are dissolved in an aqueous solution (eg water), preferably at a concentration of 50 mg / L to 1 g / L, to obtain an oil repellent solution.

[0106] According to a first embodiment of the oil repellent coating method, the oil repellent solution is then applied to an oil repellent coating bath. The same oil repellent coating bath can be used multiple times. Advantageously, when the same oil repellent coating bath is used multiple times, a device for measuring the concentration of the oil repellent agent and, optionally, a device for maintaining the concentration of the oil repellent agent should be provided to measure and, optionally, maintain the concentration over time, preferably before the oil repellent agent is brought into contact with the substrate surface in the oil repellent coating bath.

[0107] Such a concentration test means may comprise the presence of at least one V unit as described above in the copolymer. In other words, as described above, the presence of at least one V unit comprising a T group enables the concentration of the oil repellent agent in the oil repellent coating bath to be tested.

[0108] Advantageously, when the T group is a UV-absorbing group or a fluorophore, the concentration of the oil-repellent agent is determined spectroscopically (e.g., by absorbance measurement). Before testing the concentration of the oil-repellent agent in the oil-repellent coating bath, an intermediate step is to create a calibration curve for the copolymer. To do this, the copolymer is dissolved in a solvent at varying concentrations, and the absorbance of each solution is measured spectroscopically as a function of wavelength. The wavelength at which the absorbance reaches a maximum is determined, and a calibration curve A=F(concentration) is created at this wavelength. The molar extinction coefficient of the polymer can then be derived (Beer-Lambert law A=εcl).

[0109] To test the concentration of the repellent in the repellent coating bath, simply measure the absorbance of the bath liquid spectroscopically. Then, using a previously established calibration curve, the concentration of the repellent in the bath can be deduced. Based on the result, additional repellent can be added to the bath to precisely readjust the concentration.

[0110] The oil-repellent coating method according to the present invention may further include the step of drying the surface coated with the oil-repellent agent after the surface of the substrate is brought into contact with the oil-repellent agent.

[0111] According to the second embodiment of the oil-proof coating method, the oil-proof agent solution as described above is used in (including placed in) a container. Alternatively, the oil-proof agent can be placed in the container in a pure form.

[0112] Advantageously, the substrate and the oil repellent are placed in a container at ambient pressure (ie a pressure between 0.6 bar and 1.1 bar), which is then sealed.

[0113] Then, CO2 is passed into the sealed container. Advantageously, the CO2 passing time is 1 minute to 30 minutes, preferably 1 minute to 20 minutes, and more preferably 3 minutes to 15 minutes.

[0114] Advantageously, the pressure of CO2 is from 25 to 74 bar, preferably from 45 to 70 bar, more preferably from 50 to 60 bar.

[0115] Advantageously, the temperature of the CO2 is between 10°C and 80°C, preferably between 10°C and 60°C, more preferably between 15°C and 50°C.

[0116] Then, the CO2 feed is stopped and the pressure in the container is reduced. Preferably, the pressure is reduced to ambient pressure, i.e., a pressure between 0.6 bar and 1.1 bar.

[0117] The oil-repellent coated substrate is then removed from the container.

[0118] Optionally, after reducing the pressure in the container and removing the oil-repellent substrate from the container, the oil-repellent substrate can be heat-treated. For example, the oil-repellent-coated substrate can be heated in the container to a temperature between 250°C and 90°C, preferably between 30°C and 80°C, for a period of 1 to 45 minutes, preferably between 2 and 30 minutes. This heat treatment can enhance the anchoring force of the oil-repellent agent on the treated substrate surface.

[0119] The oil-repellent coating method according to the present invention may further include an additional crosslinking step after the substrate surface is contacted with the oil-repellent agent. Additional crosslinking can be advantageously achieved by providing a suitable desired functional group on the R5 side chain of the U unit. Example Example 1

[0120] The oil repellent was prepared by statistical copolymerization. 1H,1H,2H,2H-perfluorooctyl methacrylate monomer (CAS2144-53-8, R2 is CH3, X is C(O)C(CH2)2, L is C6F 13 ) were statistically copolymerized with polyethylene glycol methyl ether methacrylate monomer (CAS26915-72-0; R1 is CH3, R3 is CH3, α is 2, Y is C(O)O) and 2-methylthioethyl methacrylate monomer (CAS14216-23-0; R4 is CH3, W is C(O)O, A is (CH2)2SCH3) in the presence of an initiator system.

[0121] Figure 1 The resulting oil-resistant copolymer is shown, wherein R1 is CH3, R2 is CH3, R3 is CH3, R4 is CH3, and A is (CH2)2SCH3). The value of q is preferably between 1 and 20 (if present in the copolymer).

[0122] For copolymers with an average β value between 8 and 10, for example, a β value of 9, the m / p / q ratio is 45:45:10. For copolymers with an average β value between 18 and 20, for example, a β value of 19, the m / p / q ratio is 30:60:10. Example 2

[0123] Three different oil repellents were deposited on the surface of a steel substrate that had previously been surface pretreated using an oil repellent coating bath.

[0124] The first oil-proofing agent is the copolymer synthesized in Example 1. The oil-proofing coating bath used is an aqueous oil-proofing coating bath.

[0125] The second oil repellent contains C6 perfluoroalkyl group, namely C6F 13 The oil-proofing agent contains no hydrophilic group. The oil-proofing coating bath used is an oil-proofing coating bath containing a fluorinated solvent.

[0126] The third oil repellent is a competitive oil repellent comprising methyl nonafluoroisobutyl ether (CAS 163702-08-7), methyl nonafluorobutyl ether (CAS 163702-07-6) and a fluoroaliphatic polymer. The oil repellent coating bath used is an oil repellent coating bath containing a fluorinated solvent.

[0127] Various tests were performed to evaluate the performance of the oil repellents.

[0128] As a first test, surface tension was determined. This procedure, known to those skilled in the art, involves measuring the contact angles of three liquid droplets using a Dataphysics OCA 15 contact angle meter. These droplets, water, diiodomethane, and ethylene glycol, each have significantly different surface tensions. Based on the resulting angles, the surface tension was calculated using the Owens, Wendt, Rabel, and Kaelble (OWRK) method.

[0129] The results are shown in Table 1. The surface tension of the steel substrate surface that was not treated with the oil repellent agent was 34.95 mN / m after the surface treatment process. The surface tension of all oil repellent agents was reduced, and the surface tension value of the oil repellent agent of the present invention was equal to (within the measurement error range) C6F 13 The surface tension of the oil repellent is lower than that of competing oil repellents. The lower the surface tension, the better the oleophobicity.

[0130] The results show that the oil repellent of the present invention is C6F 13 A good alternative to oil repellents without the need for fluorinated solvents. Table 1: Surface tension of various oil repellents Example 3

[0131] The three oil-repellent agents in Example 2 were then applied to several substrates with different compositions.

[0132] To evaluate the performance of the oil repellent, #3 test oil and Contact angle measurements were performed using 9010 oil. Two oils were added and the contact angles were measured using an optical instrument (Dataphysics OCA 15). To evaluate the resistance to watch cleaning, the substrates were cleaned three times with a watch cleaning agent (an amino hydrocarbon solution) and then the contact angles were measured.

[0133] The target values for each indicator are as follows: -#3 Test oil - Initial (before cleaning): ≥60° -#3 Test Oil - After 3 washes: ≥35° -9010 oil-initial ≥70° -9010 oil-After 3 washes: ≥45°

[0134] Figure 2 Shown are the test results of the copolymers of the present invention on different substrates. Figure 3 Shows C6F 13 Test results of oil repellent, Figure 4 Results from tests of competing oil repellents are shown. from Figure 4 It can be clearly seen that each oil did not reach the target value on any substrate before and after the three washes. 13 The oil repellent achieved the target value of 9010 oil on almost all substrates. The target value of #3 oil was achieved on most substrates after using both oil repellents ( Figure 2 and 3 ).

Claims

1. A substrate comprising a surface at least partially coated with an oil repellent, characterized in that The oil repellent comprises at least one compound in the form of a copolymer, wherein the copolymer comprises M units and N units connected by covalent bonds on its main chain, wherein M is N is in R1 and R2, the same or different, are H, C1-C 10 Alkyl, C2-C 10 Alkenyl, preferably H or CH3; X and Y, which are the same or different, are spacer arms formed by a heteroatom or a linear or branched hydrocarbon chain containing at least one heteroatom and at least one carbon atom; B, the same or different, is -((CH2) α O) β -R3, where R3 is H, C1-C 10 Alkyl, C2-C 10 Alkenyl, preferably H or CH3, α is selected between 1 and 6, preferably between 2 and 3, and β is between 1 and 30, preferably between 2 and 20; L, the same or different, is a halogenated C1-C6 carbon group or a halogenated ether group represented by formula (I) in Q is a halogen atom, P, the same or different, is a straight or branched C1-C 10 Alkyl or C2-C 10 alkenyl, p is selected between 1 and 4, preferably between 2 and 3, and n is selected between 1 and 20, preferably between 1 and 10, Characterized in that the copolymer is water-soluble, and the ratio of M units to N units is between 1:10 and 10:

1.

2. The substrate according to claim 1, wherein The copolymer is a statistical copolymer, and the M units and the N units are randomly distributed.

3. The substrate according to claim 1, wherein The copolymer is a block copolymer comprising at least one M unit block connected by covalent bonds on its main chain, and at least one N unit block connected by covalent bonds on its main chain, wherein the blocks are connected together in a linear sequence by covalent bonds on its main chain.

4. The substrate according to any one of the preceding claims, characterized in that L is an at least partially fluorinated, preferably fully fluorinated, C1-C6 carbon group, or an at least partially fluorinated, preferably fully fluorinated, ether group.

5. The substrate according to any one of the preceding claims, characterized in that When the β value is 8 to 10, the ratio of the M unit to the N unit is between 1:1 and 2:1; when the β value is 18 to 20, the ratio of the M unit to the N unit is between 1:5 and 3:

5.

6. The substrate according to any one of the preceding claims, characterized in that X and Y, the same or different, are selected from C1-C 20 Ester groups, amide groups and styrene derivative groups, wherein X and Y are the same or different, optionally contain at least one heteroatom.

7. The substrate according to any one of the preceding claims, characterized in that The copolymer further comprises a K unit covalently bonded to the M and N units on its main chain, wherein K is in R4, the same or different, is H, C1-C 10 Alkyl, C2-C 10 Alkenyl, preferably H or CH3; W, identical or different, is a spacer arm formed by a heteroatom or a linear or branched hydrocarbon chain containing at least one heteroatom and at least one carbon atom; as well as A, identical or different, forms an anchoring group on the substrate.

8. The substrate according to any one of the preceding claims, characterized in that The copolymer further comprises V units covalently bonded to the M and N units on its main chain, wherein V is in R5, the same or different, is H, C1-C 10 Alkyl, C2-C 10 Alkenyl, preferably H or CH3; Z, which are the same or different, is a spacer arm formed by a heteroatom or a linear or branched hydrocarbon chain containing at least one heteroatom and at least one carbon atom; and T, which is the same or different, is a tracer group used to determine the concentration of the oil repellent agent in the oil repellent coating bath.

9. The substrate according to claim 8, characterized in that T, which are the same or different, are ultraviolet absorbing groups or fluorescent groups.

10. The substrate according to any one of the preceding claims, characterized in that The surface at least partially coated with the oil repellent is made of a material selected from the group consisting of optionally doped metals, metal oxides, metal nitrides, metal carbides, optionally doped metalloids, metalloid oxides, metalloid nitrides, metalloid carbides, alloys comprising at least one metal element, polymers, sapphire, ruby, diamond-like carbon (DLC), and combinations of two or more thereof.

11. A method for applying an oil-repellent coating to at least a portion of a substrate, comprising the following steps: - Preparation of an oil repellent comprising at least one water-soluble copolymer according to the preceding claims; - optionally, preparing the surface of the substrate; - Contact the substrate surface with the oil repellent.

12. The oil-repellent coating method according to claim 11, characterized in that: The oil repellent is prepared by copolymerizing a monomer capable of forming an M unit with a monomer capable of forming an N unit. Preferably, the monomer is selected from acrylate monomers, methacrylate monomers, acrylamide monomers, methacrylamide monomers, vinyl monomers and styrene monomers.

13. The oil-repellent coating method according to any one of claims 11 to 12, characterized in that: The oil-repellent agent comprises at least one copolymer according to claims 8 to 9, and is prepared as follows: an aqueous oil-repellent coating bath containing the oil-repellent agent dissolved in water is prepared, and a substrate surface is contacted with the oil-repellent agent in the aqueous oil-repellent coating bath, the method optionally comprising: before contacting, a step of testing the concentration of the oil-repellent agent in the aqueous oil-repellent coating bath using a tracer group; and optionally, a step of readjusting the concentration of the oil-repellent agent in the aqueous oil-repellent coating bath.

14. The oil-repellent coating method according to any one of claims 11 to 12, characterized in that: The step of contacting the substrate surface with the oil repellent comprises the following steps: - Place the substrate and oil repellent in a container at ambient pressure; - sealing the container; - CO2 is introduced into a sealed container at a pressure of 25 to 74 bar, preferably 45 to 70 bar and a temperature of 10 to 80°C, preferably 15 to 50°C; - reducing the pressure within the container; and - Removing the oil-repellent coated substrate from the container.

15. A use of a water-soluble copolymer as an oil-proofing agent for at least part of the surface of a substrate, wherein the water-soluble copolymer comprises M units and N units connected by covalent bonds on its main chain, wherein M is N is in R1 and R2, the same or different, are H, C1-C 10 Alkyl, C2-C 10 Alkenyl, preferably H or CH3; X and Y, which are the same or different, are spacer arms formed by a heteroatom or a linear or branched hydrocarbon chain containing at least one heteroatom and at least one carbon atom; B, which are the same or different, are polyether groups; L, the same or different, is a halogenated C1-C6 carbon group or a halogenated ether group represented by formula (I) in Q is a halogen atom; P, the same or different, is a straight or branched C1-C 10 Alkyl or C2-C 10 alkenyl; p is selected between 1 and 4, preferably between 2 and 3, and n is selected from 1 to 20, preferably from 1 to 10.

16. A timepiece or jewellery comprising a component comprising a substrate according to any one of claims 1 to 10.

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