Method of making article comprising antistatic coating and article comprising such coating

Abstract

Disclosed is an article comprising a substrate comprising a ceramic and / or polymer; and an antistatic coating present on at least a portion of the surface of the substrate. The antistatic coating is a cross-linked inorganic-organic hybrid coating comprising at least one epoxy functional group, wherein the coating further comprises an ammonium salt and / or phosphoric acid; wherein the antistatic coating has a surface resistivity of at most 1010 [Omega] / cm as measured by a multimeter with punctiform electrodes, and wherein the cross-linked inorganic-organic hybrid coating comprises silicon and / or titanium. A method of manufacturing such an article is also disclosed.

Description

Technical Field

[0001] The present invention relates to an article comprising a substrate and an antistatic coating on at least a portion of the surface of the substrate. The present invention also relates to a method for manufacturing such an article and to the use of such an article. Background Art

[0002] It is well known that polymeric materials and ceramics are good electrical insulators. As a consequence, one of the results is that charges on the surfaces of polymers and ceramics are not easily removed from the surface, leading to the accumulation of static charges.

[0003] Static charges can be obtained by rubbing or abrading the surface with another surface, for example, rubbing a polyester surface with a cloth. Static charges can also be generated in a variety of industrial processes, especially those carried out in a dry environment. Examples of such processes include, but are not limited to, injection molding, blow molding, thermoforming, rotational molding, part handling and collection, and assembly processes.

[0004] One of the effects of these static charges present on the surface is that objects located near the surface of the substrate (e.g., within a few centimeters) are attracted and held to the surface. This is especially true for small and lightweight particles such as dust or debris. This typically results in an undesirable aesthetic effect, namely that the surface appears dirty. This can further lead to industrial contamination and quality problems (e.g., products being rejected due to non - compliance), and even pose safety hazards, which can trigger production problems or even explosions.

[0005] In order to reduce or even suppress the attraction of such particles, the strength of the electrostatic field must be reduced, i.e., the amount of static charge present on the surface of the substrate must be reduced.

[0006] The term "antistatic" (or static - dissipative) generally refers to the property of not retaining and / or not generating significant static charges. Many articles are considered to have acceptable antistatic properties, i.e., when the surface is rubbed with a suitable cloth, it does not attract or adhere to dust or small particles. Antistatic surfaces or materials are generally able to rapidly dissipate the accumulated static charges. The ability to dissipate static charges can be quantified by measuring the time required to dissipate such static charges (i.e., the so - called "charge decay time"). The charge decay time of an antistatic article is typically preferably 400 milliseconds or less, more preferably 200 milliseconds or less, which is much shorter than the charge decay time of an electrostatic article, which is typically on the order of several tens of seconds and sometimes up to several minutes.

[0007] Currently, there are several methods for reducing the accumulation of static charges, including but not limited to so - called "internal antistatic agents" and "external antistatic compounds".

[0008] Internal antistatic agents refer to additives that are mixed with raw materials (such as polymers or monomers) during the processing of polymer materials or polymer products. Internal antistatic agents usually migrate to the polymer surface, thereby forming a surface with antistatic activity. Non-limiting examples of such antistatic agents include polyvalent alcohols, esters of long-chain fatty acids, polyols, and amino alcohols.

[0009] External antistatic compounds refer to hygroscopic compounds that are applied as a coating on the polymer surface. Due to their hygroscopicity, they absorb moisture, thereby reducing the surface resistance. Non-limiting examples of such antistatic agents include ammonium salts, sulfonium salts, or phosphates.

[0010] WO01 / 55752 discloses an antistatic, antireflective transparent coating for a transparent substrate (such as a lens, such as an ophthalmic lens). The coating comprises at least one conductive layer, and its sheet resistance is at most 10 10 ohms per square. The coating comprises a plurality of layers, wherein the antistatic layer (conductive layer) can be located at any position among the plurality of layers of the coating. The conductive layer is preferably indium tin oxide.

[0011] WO2016 / 005782 discloses an antistatic (coating) composition, which is a transparent hard coating formed on a transparent substrate. The charge decay time of the antistatic coating composition is less than 400 ms, the light transmittance is at least 90%, and the haze value is at most 0.50%. The antistatic composition comprises: a salt containing an alkali metal cation (such as a lithium cation) or a rare earth ion and a counterion; an organic compound containing an ether group and an optional hydroxyl functional group; and a binder. The composition may further comprise a filler or a crosslinking agent.

[0012] One of the disadvantages of internal antistatic agents and external antistatic agents is their compatibility with a variety of polymers or ceramics. Another disadvantage is that the antistatic effect provided is usually temporary, thus limiting the lifespan of the product. Therefore, in order to have a long-term antistatic effect, external antistatic compounds must be reapplied after a period of time, which increases the manufacturing cost and complexity. Summary of the Invention

[0013] The present invention aims to overcome one or more of the above disadvantages. One object of the present invention is to provide an article comprising a substrate and an antistatic coating, thereby protecting the surface from damage, such as scratches or indentations. Another object is to provide an article comprising a substrate and a transparent antistatic coating. Another object is to provide an article comprising a substrate and an antistatic coating having excellent adhesion to the substrate.

[0014] Another object of the present invention is to provide a method for producing such articles, which method does not require the use of irritating or toxic compounds, is carried out at moderate temperatures and does not require long processing times.

[0015] According to a first aspect of the present invention, there is disclosed an article comprising a substrate and an antistatic coating present on at least a portion of the surface of the substrate, as described in the appended claims.

[0016] The substrate comprises or consists essentially of ceramic and / or polymer. Advantageously, the polymer is polyurethane, preferably thermoplastic polyurethane.

[0017] In the present invention, "consisting essentially of" means that the amount of impurities or other components present in the substrate is advantageously less than 1% by weight, preferably less than 0.5% by weight, more preferably less than 0.1% by weight, for example less than the detection limit of the analytical technique used to determine the composition, such as X-ray photoelectron spectroscopy (XPS).

[0018] Advantageously, the article is a watch component. Non-limiting examples of watch components include watch cases and watch straps.

[0019] The antistatic coating is a crosslinked inorganic-organic hybrid coating comprising at least one epoxy functional group R 1 . The epoxy functional group optionally contains at least one halogen atom. Advantageously, the halogen atom is fluorine, chlorine, bromine or iodine. When R 1 contains two or more halogen atoms, they may be the same or different, i.e. a combination of two or more of fluorine, chlorine, bromine and iodine.

[0020] The antistatic coating, in other words the crosslinked inorganic-organic hybrid coating, further contains silicon and / or titanium. Advantageously, the crosslinked inorganic-organic hybrid coating is bonded to the ceramic and / or polymer by polar interactions between the coating and the substrate.

[0021] The crosslinked inorganic-organic hybrid coating further contains an ammonium compound and / or phosphoric acid (H3PO4). Advantageously, the coating contains an ammonium compound and phosphoric acid.

[0022] Advantageously, the ammonium compound is a trialkylammonium compound or group. Advantageously, each alkyl is independently a C1-C 20 alkyl, preferably a C1-C 12 alkyl, for example a C1-C8 alkyl, a C1-C6 alkyl, more preferably a C1-C4 alkyl, such as methyl, ethyl, propyl or butyl.

[0023] Optionally, the ammonium compound is bonded to a silane compound. Advantageously, the ammonium compound is covalently bonded to the silane compound.

[0024] Advantageously, by measurement with a multimeter equipped with a dot electrode, the surface resistivity of the antistatic coating is at most 10 10 Ω / / cm, preferably at most 10 9 Ω / cm, even more preferably at most 10 8 Ω / / cm.

[0025] Advantageously, the optical transmittance of the antistatic coating in visible light is at least 90%, preferably at least 92%, more preferably at least 95%. According to the present disclosure, a coating with an optical transmittance of at least 90% in visible light is regarded as a transparent coating. In other words, the antistatic coating of the present invention is advantageously transparent.

[0026] Advantageously, the light absorption rate of the antistatic coating is less than 5%, preferably less than 4%, for example less than 3%, more preferably less than 2%.

[0027] Advantageously, when the antistatic coating contains silicon, the crosslinked inorganic-organic hybrid coating further contains carbon-silicon bonds. Advantageously, when the antistatic coating contains titanium, the crosslinked inorganic-organic hybrid coating further contains carbon-titanium bonds. Advantageously, when the antistatic coating contains silicon and titanium, the crosslinked inorganic-organic hybrid coating further contains carbon-silicon bonds and carbon-titanium bonds.

[0028] According to a second aspect of the present invention, a method for producing an article is disclosed, the article comprising a substrate and an antistatic coating present on at least a portion of the surface of the substrate, as described in the appended claims.

[0029] The method includes providing a substrate. The substrate is advantageously as described above.

[0030] The method further includes providing a first compound according to formula (I)

[0031]

[0032] wherein

[0033] M is silicon or titanium,

[0034] R 1 is an epoxy functional group, and

[0035] R 2 、R 3 and R 4 are each independently H, C1-C 20 alkyl, C3-C 10 aryl, C2-C 20 alkenyl, C4-C 20 alkylaryl or C4-C 20 arylalkyl.

[0036] The method further includes providing a second compound according to formula (II)

[0037]

[0038] wherein

[0039] M is silicon or titanium,

[0040] R 5 is a crosslinkable functional group, and

[0041] R 6 、R 7 and R 8 are each independently H, C1-C 20 alkyl, C3-C 10 aryl, C2-C 20 alkenyl, C4-C 20 alkylaryl or C4-C 20 arylalkyl.

[0042] According to the present disclosure, a "crosslinkable functional group" refers to a functional group that can react with other functional groups. After the reaction, a covalent bond is formed, thereby forming a crosslinked polymer. A crosslinked polymer can be considered a polymer having a three-dimensional structure.

[0043] Advantageously, R 5 is a thermally crosslinkable group and / or a photocrosslinkable group. In other words, R 5 can be thermally crosslinkable, photocrosslinkable, or both.

[0044] According to the present disclosure, a "thermally crosslinkable group" refers to a group that induces and / or undergoes crosslinking of R 5 by thermal crosslinking (also known as thermal curing). Thermal curing is carried out by exposing the (thermally) crosslinkable group (and thus the prepolymer containing such crosslinkable groups in the present disclosure) to an elevated temperature (i.e., by heating the prepolymer).

[0045] According to the present disclosure, a "photocrosslinkable group" refers to a group that induces and / or undergoes crosslinking of R 5 by photochemical crosslinking (also known as photochemical curing). Photochemical curing is carried out by exposing the (photocrosslinkable group (and thus the prepolymer containing such crosslinkable groups in the present disclosure) to radiation. Advantageously, the radiation includes one or more of infrared (IR) radiation, ultraviolet (UV) radiation, or light radiation having a wavelength within the visible light (VIS) wavelength range.

[0046] Advantageously, R 5is a functional group selected from epoxy group, (meth)acrylate group, ester group, mercapto group, vinyl group and (meth)acrylated urethane. In the present disclosure, the "(meth)acrylate group" means that the functional group can be acrylate group or methacrylate group.

[0047] Advantageously, R 2 , R 3 , R 4 , R 6 , R 7 and R 8 are each independently H or C1-C 20 alkyl, preferably C1-C8 alkyl, more preferably C1-C6 alkyl, and most preferably C1-C4 alkyl. In particular, R 2 , R 3 , R 4 , R 6 , R 7 and R 8 are each independently methyl (-CH3, i.e., C1 alkyl) or ethyl (-C2H5, i.e., C2 alkyl).

[0048] The method further includes hydrolyzing the first compound and the second compound in the presence of water. After hydrolysis, the C1-C8 alkyl chain of any one of R 2 , R 3 , R 4 , R 6 , R 7 and R 8 is converted to a hydrogen atom or reacts to form a hydrogen atom, thereby forming a hydroxyl group. The hydrolysis reaction also produces an alcohol molecule of the formula C x H 2x+1 OH, where x is the number of carbon atoms in the C1-C8 alkyl chain of R 2 , R 3 , R 4 , R 6 , R 7 and R 8 (i.e., x is from 1 to 8).

[0049] The method further includes condensing the hydrolyzed first compound with the hydrolyzed second compound. During condensation, water molecules are formed and removed. A prepolymer is obtained from the hydrolyzed first compound and the hydrolyzed second compound. The prepolymer contains R 1 and R 5 as functional groups. The prepolymer can be considered a so-called "sol".

[0050] The method further includes adding an ammonium compound and / or phosphoric acid to the prepolymer. Advantageously, the ammonium compound is as described above. Advantageously, the ammonium compound and / or phosphoric acid are at least partially dissolved or dispersed in the prepolymer.

[0051] Advantageously, an ammonium compound and / or phosphoric acid is added such that the prepolymer comprising one or more ammonium salts and / or phosphoric acid comprises 5 wt% to 50 wt%, preferably 10 wt% to 45 wt%, more preferably 15 wt% to 40 wt%, for example 20 wt% to 30 wt% of the ammonium compound and / or phosphoric acid, based on the total weight of the prepolymer comprising the ammonium compound and / or phosphoric acid.

[0052] The prepolymer comprising the ammonium compound and / or phosphoric acid is applied to at least a part of the surface of the substrate. The application can be carried out by methods known in the art, such as casting or dipping the substrate in the prepolymer, spraying or electrospraying the prepolymer onto the substrate, bar coating or roll-to-roll coating.

[0053] The method further comprises inducing crosslinking of the prepolymer comprising the ammonium compound and / or phosphoric acid applied to at least a part of the surface of the substrate. Advantageously, the prepolymer is crosslinked by crosslinkable functional groups R 5 by crosslinking.

[0054] When R 5 is a thermally crosslinkable functional group, advantageously, the crosslinking is induced and / or carried out by exposing the prepolymer to a temperature up to 250 °C, advantageously, a temperature of 25 °C to 250 °C, preferably 30 °C to 250 °C, for example 40 °C to 225 °C, more preferably 50 °C to 200 °C, even more preferably 100 °C to 175 °C.

[0055] When R 5 is a photocrosslinkable functional group, advantageously, the crosslinking is induced and / or carried out by exposing the prepolymer to radiation. Advantageously, the radiation is IR radiation, UV radiation or a combination thereof.

[0056] When R 5 is a thermally crosslinkable and photocrosslinkable functional group, advantageously, the crosslinking is induced and / or carried out by exposing the prepolymer to a temperature up to 250 °C and exposing it to radiation.

[0057] After the prepolymer is crosslinked, an article comprising a substrate and an antistatic coating covering at least a part of the surface of the substrate is obtained. The antistatic coating comprises at least one functional group R 1 (so-called "gel"). The antistatic coating is a crosslinked inorganic-organic hybrid coating. The surface resistivity of the antistatic coating is at most 10 10 Ω / / cm, preferably at most 10 9 Ω / cm, even more preferably at most 10 8 Ω / cm, measured by a multimeter with dot electrodes.

[0058] Advantageously, the crosslinked inorganic-organic hybrid coating is bonded to the ceramic and / or polymer of the substrate by polar interactions.

[0059] According to a third aspect of the present invention, there is disclosed the use of the article of the first aspect as described in the appended claims. Advantageously, the article is used in a watch.

[0060] According to a fourth aspect of the present invention, there is disclosed the use of the method of the second aspect as described in the appended claims. Advantageously, the method is used for obtaining an antistatic watch component.

[0061] Advantages of the method of the present disclosure include, but are not limited to: the ability to apply an antistatic coating to various substrates, wherein the antistatic coating has excellent adhesion to the substrate. Another advantage is that the method is particularly suitable for uniformly applying an antistatic coating to a substrate having a complex geometry. The coating thickness can be well controlled such that the thickness remains within the tolerance range. Such tolerances are typically determined by the use of the resulting article. Brief Description of the Drawings

[0063] Aspects of the present invention will now be described in more detail with reference to the drawings, in which like reference numerals represent like features and in which:

[0064] - Figure 1 schematically represents the steps of the method according to the present disclosure,

[0065] - Figure 2 shows a ceramic plate including an antistatic coating according to the present invention,

[0066] - Figure 3 shows a ceramic watch case including an antistatic coating according to the present invention,

[0067] - Figure 4A and 4B respectively show the (anti)static behavior of untreated and treated ceramic plates,

[0068] - Figure 5 shows a TPU watch strap including an antistatic coating according to the present invention. Detailed Description of the Invention

[0070] Figure 1 Schematically shows the steps of the method according to the present disclosure. Method 10 includes step 1 of providing a substrate. Advantageously, the substrate comprises or consists essentially of ceramic and / or polymer.

[0071] Advantageously, the substrate comprises ceramic or a ceramic combination. Particularly suitable ceramics are bioceramics. According to the present disclosure, a bioceramic is a hybrid composition of a ceramic material or compound and a bio-derived material. For example, the bio-derived material can be derived from castor oil.

[0072] Alternatively or additionally, advantageously, the substrate comprises a polymer or a combination of polymers, including copolymers. Non-limiting examples of polymers and copolymers include polyurethanes, such as thermoplastic polyurethanes (TPU), polyethylene, polypropylene, polyesters (e.g., PBT or PET), polyamides (e.g., PA6, PA6-6), polyimides, polyamide-imides, polystyrene, polytetrafluoroethylene (PTFE), polymethyl methacrylate, polycarbonate, and methacrylate-acrylonitrile-butadiene-styrene (MABS).

[0073] Optionally, the substrate may comprise other additives. Such additives may be additives known in the art, such as fillers or flame retardants.

[0074] The method further comprises providing a first compound 3 according to formula (I), wherein formula (I) is as described above.

[0075] Advantageously, R 1 comprises or consists essentially of epoxy functional groups (i.e., ethylene oxide functional groups). For example, R 1 can be an α-epoxy group or a 1,2-epoxy group containing a three-membered ring structure.

[0076] Advantageously, "C1-C 20 alkyl" includes an alkyl functional group having 1 to 20 carbon atoms in the chain. Advantageously, C1-C 20 alkyl is C1-C 12 alkyl, preferably C1-C 10 alkyl, such as C1-C8 alkyl, C1-C6 alkyl, or C1-C4 alkyl.

[0077] Advantageously, "C3-C 10 aryl" includes an aryl functional group having 3 to 10 carbon atoms in the chain. For example, R 1 can contain a phenyl functional group, or can be a C3-C 20 alkylphenyl.

[0078] Advantageously, "C2-C 20 alkenyl" includes an alkenyl functional group having 2 to 20 carbon atoms in the chain. Advantageously, C2-C 20 alkenyl is C2-C 12 alkenyl, preferably C2-C 10 alkenyl, such as C2-C8 alkenyl, C2-C6 alkyl, or C2-C4 alkenyl.

[0079] The method further comprises providing a second compound 4 according to formula (II), wherein formula (II) is as described above.

[0080] Advantageously, the first compound and the second compound are hydrolyzed as described above 5. Advantageously, the hydrolyzed first compound and the hydrolyzed second compound are condensed as described above 6 to obtain a prepolymer.

[0081] The method further comprises adding an ammonium compound and / or phosphoric acid 7 to the prepolymer. Advantageously, the ammonium compound is as described above. Advantageously, the ammonium compound and / or phosphoric acid are added to the prepolymer in an amount as described above.

[0082] Optionally, other components or substances can be added to the prepolymer. For example, a surfactant can be added to the prepolymer. Advantageously, when a surfactant is added, its addition amount is 0.5 wt% to 30 wt% based on the total weight of the prepolymer containing the ammonium compound and / or phosphoric acid.

[0083] Advantageously, the prepolymer containing the ammonium compound and / or phosphoric acid is applied to at least a part of the surface of the substrate 8 as described above. Various application methods known in the art can be used. A preferred method includes dipping the substrate into the prepolymer so that the surface (a part) of the substrate to which the prepolymer is to be applied comes into contact with the prepolymer. The substrate can be dipped into the prepolymer by immersing the substrate into the prepolymer.

[0084] The method further comprises crosslinking 9 the prepolymer to obtain an antistatic coating on the substrate. The crosslinking 9 is advantageously carried out as described above.

[0085] Optionally, before applying 8 the prepolymer to at least a part of the surface of the substrate, the substrate can be pretreated 2 (so-called pretreatment). Suitable examples of pretreatment include cleaning at least a part of the surface of the substrate (so-called pre-cleaning). The pre-cleaning can be carried out by methods known in the art. Non-limiting examples include grinding and polishing, chemical cleaning, ultrasonic cleaning, sandblasting, atmospheric or reduced-pressure plasma treatment, corona treatment (air plasma), and alkali treatment.

[0086] Advantageously, the antistatic coating is an inorganic-organic hybrid coating. Advantageously, the antistatic coating is a crosslinked inorganic-organic hybrid coating. Advantageously, the antistatic coating is bonded to the surface of the substrate through one or more polar interactions.

[0087] Advantageously, the crosslinked inorganic-organic hybrid coating contains one or more of silicon, titanium, zirconium, aluminum, iron, or boron, preferably silicon and / or titanium.

[0088] Advantageously, the crosslinked inorganic-organic hybrid coating further contains carbon-silicon bonds.

[0089] Advantageously, the coating thickness is from 1 μm to 20 μm, preferably from 1.2 μm to 10 μm, such as from 1.5 μm to 5 μm. It is understood that the optimal coating thickness depends in particular on the substrate (especially its composition and shape), the desired saturation and transparency of the coating, and the intended use of the article. Examples

[0090] Example 1

[0091] A ceramic plate and a ceramic watch case are provided as substrates.

[0092] A prepolymer is prepared. A trimethylammonium compound covalently bonded to a silane compound and phosphoric acid are added to the prepolymer in an amount such that the prepolymer containing trimethylammonium and phosphoric acid contains 30% by weight of the trimethylammonium compound and phosphoric acid.

[0093] The prepolymer containing the trimethylammonium compound and phosphoric acid is applied to the ceramic substrate by immersing the ceramic substrate in the prepolymer at a rate of 100 mm / min. After removing the ceramic substrate from the prepolymer, the prepolymer present on the ceramic is crosslinked by thermally curing the substrate at 95 °C for 1 hour.

[0094] Figure 2 The flat ceramic substrate after crosslinking is shown. Figure 3 The watch case after crosslinking is shown. It can be clearly seen that the antistatic coating uniformly covers the surface.

[0095] The antistatic properties are tested by the following method: the surface is charged by rubbing it vigorously with a textile paper towel, and then the rubbed surface is placed directly above a tray containing ashes. The distance between the rubbed surface and the tray is 3 to 5 cm. The same test is also carried out on a reference ceramic substrate without any antistatic treatment.

[0096] Figure 4A It is shown that the reference ceramic substrate adsorbed a large amount of ashes, indicating significant electrostatic adsorption. Figure 4B It is shown that the ceramic substrate with the antistatic coating of the present invention did not adsorb any ashes, clearly demonstrating the antistatic properties. Similar results were also obtained for the ceramic watch case.

[0097] The adhesion of the ceramic sample is tested in accordance with ASTM 3359-95A, and the result shows that the adhesion is 100% (no delamination is found).

[0098] Example 2

[0099] A thermoplastic polyurethane (TPU) watch strap is provided as the substrate.

[0100] The prepolymer of Example 1 was applied to the TPU watchband by immersing the watchband into the prepolymer at a rate of 100 mm / min. After taking the TPU watchband out of the prepolymer, the prepolymer present on the watchband was crosslinked by thermally curing the substrate at 95 °C for 1 hour.

[0101] Figure 5 The crosslinked TPU watchband is shown. It can be clearly seen that the antistatic coating uniformly covers the surface.

[0102] The antistatic properties were tested as described in Example 1. The TPU with the antistatic coating of the present invention did not adsorb any ash, clearly demonstrating the antistatic properties, while the reference TPU without any antistatic treatment adsorbed a large amount of ash.

[0103] The adhesion of the treated TPU watchband was tested in accordance with ASTM 3359-95A, and the result showed that the adhesion was 100% (no delamination was found).

[0104] Nomenclature

[0105] 1. Provide a substrate

[0106] 2. Optional substrate pretreatment

[0107] 3. Provide a first compound

[0108] 4. Provide a second compound

[0109] 5. Hydrolysis

[0110] 6. Condensation

[0111] 7. Add an ammonium compound and / or phosphoric acid

[0112] 8. Apply to the substrate

[0113] 9. Crosslinking

[0114] 10. Method

Claims

1. An article comprising a substrate and an antistatic coating present on at least a portion of the surface of the substrate, wherein the substrate comprises a ceramic and / or a polymer, and wherein the antistatic coating is a crosslinked inorganic-organic hybrid coating comprising at least one epoxy functional group R 1 ​ It is characterized in that The crosslinked inorganic-organic hybrid coating contains an ammonium compound and phosphoric acid, and the antistatic coating has a surface resistivity measured by a multimeter with a dot electrode of at most 10 10 Ω / cm, and the crosslinked inorganic-organic hybrid coating contains silicon and / or titanium.

2. The article according to claim 1, wherein the ammonium compound is a trialkylammonium group, optionally bonded to a silane compound.

3. The article according to any one of the preceding claims, wherein the surface resistivity of the antistatic coating measured by a multimeter with a dot electrode is at most 10 9 Ω / cm.

4. The article according to any one of the preceding claims, wherein the optical transmittance of the coating in visible light is at least 90%, preferably at least 95%.

5. The article according to claim 3, wherein the light absorption rate of the coating is less than 5%, preferably less than 2%.

6. The article according to any one of the preceding claims, wherein when the coating contains silicon and / or titanium respectively, the crosslinked inorganic-organic hybrid coating contains carbon-silicon bonds and / or carbon-titanium bonds.

7. The article according to any one of the preceding claims, wherein the substrate contains ceramics, and the ceramics are a mixed composition of ceramics and biogenic compounds.

8. The article according to any one of the preceding claims, wherein the substrate contains a polymer, and the polymer is polyurethane, preferably thermoplastic polyurethane.

9. The article according to any one of the preceding claims, wherein the article is a watch component.

10. A method (10) for producing an article, the article comprising a substrate and an antistatic coating present on at least a portion of the surface of the substrate, wherein the substrate contains ceramics and / or polymers, the method comprising: - providing a substrate (1) containing ceramics and / or polymers, - providing a first compound (3) according to formula (I) and a second compound (4) according to formula (II) wherein M is silicon or titanium, R 1 is an epoxy functional group R 5 is a crosslinkable functional group, R 2 、R 3 、R 4 、R 6 、R 7 and R 8 each independently is H, C1-C 20 alkyl, C3-C 10 aryl, C2-C 20 alkenyl, C4-C 20 alkylaryl or C4-C 20 arylalkyl, - hydrolyzing the first compound and the second compound (5) in the presence of water, -The first compound that undergoes condensation hydrolysis and the second compound that undergoes hydrolysis (6), thereby obtaining a prepolymer containing R 1 and R 5 as functional groups - adding an ammonium compound and phosphoric acid to the prepolymer (7), - applying the prepolymer containing the ammonium compound and / or phosphoric acid to at least a portion of the surface of the substrate (8), and - By exposing a prepolymer containing an ammonium compound and / or phosphoric acid to one or more of a temperature up to 250 °C, UV radiation, or IR radiation, crosslinking (9) of the crosslinkable functional group R is induced, thereby obtaining an article including a substrate and an antistatic coating covering at least a part of the surface of the substrate. 5 ​ Characterized in that the antistatic coating is a crosslinked inorganic-organic hybrid coating containing at least one functional group R 1 and the surface resistivity of the antistatic coating measured by a multimeter with a dot electrode is at most 10 10 Ω / cm.

11. The method according to claim 10, wherein the ammonium compound is a trialkylammonium group, optionally bonded to a silane compound.

12. The method (10) according to any one of claims 10 to 11, wherein R 5 is a functional group selected from epoxy group, (meth)acrylate group, ester group, mercapto group, vinyl group and (meth)acrylated urethane.

13. The method according to claim 10 or 12, wherein the crosslinking is carried out at a temperature of 50 °C to 200 °C, preferably 100 °C to 175 °C.

14. Use of the article according to any one of claims 1 to 9 in a watch.

15. Use of the method according to any one of claims 10 to 13 for obtaining an antistatic watch component.

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