Coating and preparation method therefor

Abstract

A coating and a preparation method therefor. The coating is a polymerized coating deposited on the surface of a base material by means of a chemical reaction between an organic monomer of a perfluoropolyether derivative and / or a perfluoropolyether and a parylene active monomer subjected to high-temperature pyrolysis. The present coating solves the problem where the surface energy ranges of existing parylene protective coatings are all similar.

Description

A coating and a preparation method thereof

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on November 15, 2023, with application number 202311528758.8 and invention name “A coating and its preparation method”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention belongs to the field of coating protection, and in particular relates to a protective coating formed by high-temperature decomposition of parylene and a preparation method thereof. Background Art

[0003] Parylene is a new conformal coating material developed and applied by UnionCarbide Co. in the United States in the mid-1960s. It is prepared using a vacuum vapor deposition process, where reactive small molecules form a conformal polymer film on the substrate surface. Parylene is a protective polymer material, known in Chinese as poly(p-xylene). Depending on its molecular structure, parylene can be classified into various types, including N, C, D, F, and HT. Parylene coatings are polymers of p-xylene. P-xylene is first heated to 680°C to form a reactive p-xylene dimer. After the temperature is lowered in the deposition chamber, this dimer is deposited on the substrate surface, forming a polymer film. Due to the highly symmetrical structure of p-xylene and its zero dipole moment, the presence of benzene rings gives the polymer molecules a large free volume. Furthermore, the relatively high molecular weight of the polymer results in a highly dense coating. These characteristics give parylene coatings low water and gas permeability, a high barrier effect, and resistance to moisture, water, rust, and acid and alkali corrosion. However, due to the characteristics of the molecular structure of parylene, the surface energy range of its coating is relatively single, and its application scenarios are greatly limited.

[0004] Summary of the Invention

[0005] In order to overcome the problem of the single surface energy range of existing parylene protective coatings, the specific embodiment of the present invention provides the following coating and preparation method thereof:

[0006] A coating is a polymer coating deposited on the surface of a substrate by chemical reaction between a gaseous organic monomer and a parylene active monomer cracked at high temperature, wherein the organic monomer comprises perfluoropolyether and / or a perfluoropolyether derivative.

[0007] Optionally, the perfluoropolyether or perfluoropolyether derivative has a structure shown in the following formula (1):

[0008] In formula (1), R1 is a hydrogen atom, a halogen atom, a C1-C4 hydrocarbon group, a C1-C4 halogenated hydrocarbon group, a hydroxyl group, a carboxyl group, an isocyanate group, an ester group, or a group represented by the following formula (2) or (3).

[0009] R2 and R3 are independently selected from a linker, an amide group, a sulfonyl group, a carbamate group, a C1-C4 alkylene group, a C1-C4 halogenated alkylene group, a C 6-20 At least one of an arylene group or a group of the following formula (4),

[0010] R4 is a hydrogen atom, a halogen atom, a C1-C4 alkyl group, a C1-C4 haloalkyl group, a hydroxyl group, a carboxyl group, an isocyanate group, an ester group or -COF, n is an integer from 1 to 10, m is an integer from 1 to 200, m C n F 2n The O groups are independent of each other.

[0011] In formula (2), R5, R6 and R7 are independently selected from hydrogen atoms, C1-C 10 Alkyl or C1-C 10 The halogenated alkyl group, in formula (3), R8, R9 and R 10 are independently selected from hydrogen atoms, halogen atoms, C1-C 10 Alkyl, C1-C 10 Halogenated alkyl, C1-C 10 Alkoxy or C1-C 10 wherein X is O, S or NH, k is an integer from 1 to 10, j is an integer from 1 to 20, and j C k F 2k The O groups are independent of each other.

[0012] Optionally, in formula (1), R1 is a fluorine atom, a C1-C4 perfluoroalkyl group, a hydroxyl group, a carboxyl group, a group represented by formula (2) or formula (3), R2 and R3 are independently selected from a connecting bond, a C1-C2 alkylene group, a C1-C2 perfluoroalkylene group or a group represented by formula (4), R4 is a fluorine atom, -COF, a C1-C4 perfluoroalkyl group, a hydroxyl group or a carboxyl group, n is an integer of 1 to 3, and m is an integer of 5 to 50.

[0013] In formula (2), R5, R6 and R7 are independently selected from hydrogen atoms or methyl groups. In formula (3), R8 is a C1-C4 alkyl group or a C1-C4 alkoxy group. R9 and R 10 They are independently selected from hydrogen atom, C1-C4 alkyl group or C1-C4 alkoxy group. In formula (4), k is an integer of 1 to 4, and j is an integer of 1 to 4.

[0014] Optionally, R1 is a fluorine atom or a C1-C4 perfluoroalkyl group, R2 and R3 are a connecting bond or a C1-C2 perfluoroalkylene group, and R4 is a fluorine atom, -COF or a C1-C4 perfluoroalkyl group.

[0015] Optionally, R1 and R4 are hydroxyl groups, and R2 and R3 are independently selected from at least one of a C1-C4 alkylene group and a group of formula (4).

[0016] Optionally, R1 is a carboxyl group or a group represented by formula (2), R2 is a connecting bond, or at least one of a C1-C4 alkylene group and a group represented by formula (4), R3 is a connecting bond, and R4 is a fluorine atom or a C1-C4 perfluoroalkyl group.

[0017] Optionally, the mass ratio of the parylene active monomer to the perfluoropolyether and / or perfluoropolyether derivative is 10:1 to 1:10.

[0018] Optionally, the mass ratio of the parylene active monomer to the perfluoropolyether and / or perfluoropolyether derivative is 5:1 to 5:1.

[0019] Optionally, the parylene is at least one of parylene N powder, C powder, D powder, F powder or HT powder.

[0020] A method for preparing one or more of the above coatings, comprising:

[0021] providing a substrate, and placing the substrate in a vacuum deposition chamber;

[0022] Gaseous organic monomers and parylene active monomers after high-temperature cracking are introduced into the vacuum deposition chamber;

[0023] The organic monomer and the parylene reactive monomer react in a vacuum deposition chamber to form the coating on the surface of the substrate.

[0024] A device, wherein at least a portion of the surface of the device has the above-mentioned coating.

[0025] The coating of the specific embodiment of the present invention is a polymer coating deposited on the surface of the substrate through a chemical reaction between an organic monomer including perfluoropolyether and / or a perfluoropolyether derivative and a parylene active monomer after high-temperature cracking. The coating overcomes the problem that the surface energy range of existing parylene protective coatings is relatively single and the application scenarios are greatly limited. DETAILED DESCRIPTION

[0026] A specific embodiment of the present invention provides a coating, which is a polymer coating deposited on the surface of a substrate by chemical reaction between a gaseous organic monomer and a parylene active monomer after high-temperature decomposition, wherein the organic monomer includes perfluoropolyether and / or a perfluoropolyether derivative.

[0027] The inventors of the present invention have found that the parylene active monomer after high-temperature pyrolysis can react with perfluoropolyether and / or perfluoropolyether derivatives to form a polymer coating with different hydrophobic effects on the surface of the substrate through chemical reaction.

[0028] Perfluoropolyether (PFPE) is a class of polymers containing -CF2-O-CF2- chains that can serve as an alternative to long-chain perfluoroalkyl compounds. They exhibit properties such as chemical inertness, oxidation resistance, a low glass transition temperature, and lubricity. Perfluoropolyethers also have low surface energy (10-14 mN / m) and excellent hydrophobicity and oleophobicity. Furthermore, the perfluorocarbon chains in the backbone are interrupted by oxygen atoms, resulting in the absence of long-chain perfluoroalkyl groups and a lack of bioaccumulation, eliminating the environmental challenges faced by long-chain fluoroalkyl compounds.

[0029] The coating of the specific embodiment of the present invention ensures a good hydrophobic and oleophobic effect, avoids the restrictions of regulations such as PFOA and PFOS, and is environmentally friendly.

[0030] In some embodiments of the coating of the present invention, the perfluoropolyether or perfluoropolyether derivative has a structure shown in the following formula (1):

[0031] In formula (1), R1 is a hydrogen atom, a halogen atom, a C1-C4 hydrocarbon group, a C1-C4 halogenated hydrocarbon group, a hydroxyl group, a carboxyl group, an isocyanate group, an ester group, or a group represented by the following formula (2) or (3).

[0032] R2 and R3 are independently selected from a linker, an amide group, a sulfonyl group, a carbamate group, a C1-C4 alkylene group, a C1-C4 halogenated alkylene group, a C 6-20 At least one of an arylene group or a group of the following formula (4),

[0033] R4 is a hydrogen atom, a halogen atom, a C1-C4 alkyl group, a C1-C4 haloalkyl group, a hydroxyl group, a carboxyl group, an isocyanate group, an ester group or -COF, n is an integer from 1 to 10, m is an integer from 1 to 200, m C n F 2n The O groups are independent of each other.

[0034] In formula (2), R5, R6 and R7 are independently selected from hydrogen atoms, C1-C 10 Alkyl or C1-C10 The halogenated alkyl group, in formula (3), R8, R9 and R 10 are independently selected from hydrogen atoms, halogen atoms, C1-C 10 Alkyl, C1-C 10 Halogenated alkyl, C1-C 10 Alkoxy or C1-C 10 wherein X is O, S or NH, k is an integer from 1 to 10, j is an integer from 1 to 20, and j C k F 2k The O groups are independent of each other.

[0035] In the coating of the specific embodiment of the present invention, the alkyl group or alkylene group may be a linear structure alkyl group or alkylene group, or a branched structure alkyl group or alkylene group.

[0036] In the coating of the specific embodiment of the present invention, the hydrocarbon group can be a hydrocarbon group with a straight chain structure or a hydrocarbon group with a branched chain structure.

[0037] In the coating of the specific embodiment of the present invention, in some specific embodiments, the hydrocarbon group is an alkyl group, and in some specific embodiments, the hydrocarbon group is an alkenyl group or an alkynyl group.

[0038] In some specific embodiments of the coating of the present invention, in formula (1), R1 is a fluorine atom, a C1-C4 perfluoroalkyl group, a hydroxyl group, a carboxyl group, or a group represented by formula (2) or formula (3).

[0039] In some embodiments of the coating of the present invention, R2 and R3 are independently selected from a connecting bond, a C1-C2 alkylene group, i.e., a methylene group or an ethylene group, a C1-C2 perfluoroalkylene group or a group of formula (4).

[0040] In some embodiments of the coating according to the specific embodiment of the present invention, R4 is a fluorine atom, -COF, a C1-C4 perfluoroalkyl group, a hydroxyl group, or a carboxyl group.

[0041] In some specific embodiments of the coating according to the specific embodiment of the present invention, n is an integer of 1 to 3, and m is an integer of 5 to 50.

[0042] In some specific embodiments of the coating of the present invention, in formula (2), R5, R6 and R7 are independently selected from hydrogen atoms or methyl groups.

[0043] In some embodiments of the coating of the present invention, in formula (3), R8 is a C1-C4 alkyl group or a C1-C4 alkoxy group, and R9 and R 10They are independently selected from hydrogen atom, C1-C4 alkyl or C1-C4 alkoxy, the C1-C4 alkyl is specifically exemplified by methyl, ethyl, propyl or butyl, and the C1-C4 alkoxy is specifically exemplified by methoxy, ethoxy, propoxy or butoxy.

[0044] In the coating of the specific embodiment of the present invention, in some specific embodiments, k is an integer of 1 to 4, j is an integer of 1 to 4, and in some specific embodiments, in formula (4), k is an integer of 1 to 2, j is an integer of 1 to 2.

[0045] In some embodiments of the coating of the present invention, R1 is a fluorine atom or a C1-C4 perfluoroalkyl group, R2 and R3 are a connecting bond or a C1-C2 perfluoroalkylene group, and R4 is a fluorine atom, -COF, or a C1-C4 perfluoroalkyl group. For example, in some embodiments, the perfluoropolyether has the following structure: CF3CF2CF2O[CF(CF3)CF2O] x1 CF(CF3)COF, x1 is an integer greater than 1. In some embodiments, the perfluoropolyether has the following structure: CF3O(C3F6O) x2 (CF2O) x3 CF3, x2 and x3 are integers greater than 1. In some embodiments, the perfluoropolyether has the following structure: CF3O(C2F4O) x4 (CF2O) x5 CF3, x4 and x5 are integers greater than 1. In some embodiments, the perfluoropolyether has the following structure: C3F7O(CF2CF2CF2O) x6 C2F5,x6 is an integer greater than 1.

[0046] In some embodiments of the coating of the present invention, R1 and R4 are hydroxyl groups, and R2 and R3 are independently selected from at least one of a C1-C4 alkylene group and a group of formula (4). For example, in some embodiments, the perfluoropolyether derivative has the structural formula: HO-CH2CF2O(CF2O) y1 (CF2CF2O) y2 CF2CH2-OH, y1 and y2 are integers greater than 1. In some embodiments, the perfluoropolyether derivative has the structural formula: HO-(CH2CH2O) y3 CH2CF2O(CF2O) y4 (CF2CF2O) y5 CF2CH2(OCH2CH2) y3 -OH, y4 and y5 are integers greater than 1, and y3 is 1 or 2.

[0047] In the coating of the specific embodiment of the present invention, in some specific embodiments, R1 is a carboxyl group or a group represented by formula (2), R2 is a connecting bond, or at least one of a C1-C4 alkylene group and a group represented by formula (4), R3 is a connecting bond, and R4 is a fluorine atom or a C1-C4 perfluoroalkyl group. Specifically, for example, in some specific embodiments, the perfluoropolyether derivative is perfluoropolyether methacrylate, perfluoropolyether acrylate or perfluoropolyether carboxylic acid.

[0048] In the coating of the specific embodiment of the present invention, in some specific embodiments, the perfluoropolyether derivative can also include perfluoropolyether methyl ester, perfluoropolyether dimethylamino propionamide, perfluoropolyether carbonyl n-butyl thioester, perfluoropolyether amide ethyl alcohol, perfluoropolyether isocyanate or perfluoropolyether amide acrylate, etc.

[0049] In some embodiments of the coating of the present invention, specific examples of perfluoropolyether or perfluoropolyether derivatives include and In some embodiments, the perfluoropolyether or perfluoropolyether derivative is selected from SOLVAY D7 0 0, or In some embodiments, the perfluoropolyether or perfluoropolyether derivative is selected from 3M's Novec fluorinated liquid.

[0050] In the coating of the specific embodiment of the present invention, in some specific embodiments, the mass ratio of the parylene active monomer to the monomer of the structure represented by formula (1) is 10:1 to 1:10. In some specific embodiments, the mass ratio of the parylene active monomer to the monomer of the structure represented by formula (1) is 5:1 to 1:5. Specifically, for example, it can be 5:1, 4:1, 3:1, 2:1, 1:1, 2:1, 3:1, 4:1 or 5:1.

[0051] In some embodiments of the coating according to the specific embodiment of the present invention, the parylene is at least one of parylene N powder, C powder, D powder, F powder or HT powder.

[0052] The coating of the specific embodiment of the present invention, in some specific embodiments, the thickness of the coating is 1 to 10000 nm, in some specific embodiments, the thickness of the coating is 1 to 1000 nm, in some specific embodiments, the thickness of the coating is 5 to 100 nm, and in some specific embodiments, the thickness of the coating is 10 to 50 nm.

[0053] In the coating of the specific embodiment of the present invention, in some specific embodiments, the substrate is a metal, specifically for example, iron, magnesium, aluminum, copper or their alloys. In other specific embodiments, the substrate is various plastics, fabrics, glass, ceramics, paper, electrical components or optical instruments. Specifically, the electrical component can be a printed circuit board (PCB), an electronic product or a semi-finished electronic assembly. When the substrate is an electronic product, examples include but are not limited to mobile phones, tablet computers, keyboards, e-readers, wearable devices, displays, headphones, etc. The substrate can also be any suitable electrical component of the electrical component, specifically, the electrical component can be a resistor, capacitor, transistor, diode, amplifier, relay, transformer, battery, fuse, integrated circuit, switch, LED, LED display, piezoelectric element, optoelectronic component or antenna or oscillator, etc.

[0054] In the coating of the specific embodiments of the present invention, in some specific embodiments, the organic monomer is a perfluoropolyether and / or perfluoropolyether derivative monomer. In other specific embodiments, the organic monomer includes other organic monomers other than appropriate perfluoropolyether and / or perfluoropolyether derivative monomers without affecting the overall coating performance.

[0055] In some embodiments of the coating of the present invention, the substrate is a substrate that has been surface treated, such as plasma surface treatment, thermal oxygen surface treatment, coating with other coatings, etc.

[0056] A specific embodiment of the present invention further provides a method for preparing the coating as described above, comprising:

[0057] providing a substrate, and placing the substrate in a vacuum deposition chamber;

[0058] Gaseous organic monomers and parylene active monomers after high-temperature cracking are introduced into the vacuum deposition chamber;

[0059] The organic monomer and the parylene reactive monomer react in a vacuum deposition chamber to form the coating on the surface of the substrate.

[0060] The method for preparing the coating according to the specific embodiment of the present invention, the descriptions of the substrate, the organic monomer, and parylene are as described above.

[0061] In the method for preparing the coating of a specific embodiment of the present invention, in some specific embodiments, the temperature in the vacuum deposition chamber is 20°C-80°C, for example, it can be 20°C, 30°C, 40°C, 50°C, 60°C, 70°C or 80°C, etc.

[0062] In the method for preparing the coating according to a specific embodiment of the present invention, in some specific embodiments, the pressure in the vacuum deposition chamber is 1-500 mTorr, and in some specific embodiments, the pressure in the vacuum deposition chamber is 5-100 mTorr.

[0063] In some specific embodiments of the method for preparing the coating according to a specific embodiment of the present invention, the organic monomer is vaporized and then enters the vacuum deposition chamber through an organic monomer inlet. The parylene active monomer is sublimated from parylene powder in a sublimation chamber and then enters a cracking chamber for cracking, and then enters the vacuum deposition chamber through a parylene active monomer inlet.

[0064] In the method for preparing the coating of a specific embodiment of the present invention, in some specific embodiments, the vaporization temperature of the organic monomer is 50°C-180°C, for example, it can be 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C or 180°C, etc., and the vaporization occurs under vacuum conditions.

[0065] In the method for preparing the coating according to a specific embodiment of the present invention, in some specific embodiments, the sublimation temperature in the sublimation chamber is 80°C to 200°C, for example, it can be 80°C, 100°C, 120°C, 150°C, 180°C or 200°C, etc., and sublimation occurs under vacuum conditions.

[0066] In the method for preparing the coating according to a specific embodiment of the present invention, in some specific embodiments, the pyrolysis temperature in the pyrolysis chamber is 500-750°C, for example, 500°C, 600°C, 650°C, 700°C or 750°C, etc.

[0067] A specific embodiment of the present invention further provides a device, wherein at least a portion of the surface of the device has the above-mentioned coating. In some specific embodiments, the above-mentioned coating is deposited on a portion of the surface or the entire surface of the device.

[0068] The present invention is further described below with reference to specific examples.

[0069] Example

[0070] Test method description

[0071] Coating thickness test: The coating was applied to the silicon wafer and tested using the American Filmetrics F20-UV-film thickness gauge.

[0072] Water drop angle test: tested according to GB / T 30447-2013 standard.

[0073] Color difference test: Calculated according to GB 11186.3-1989 standard, using a Minolta CM-5 portable colorimeter to calculate the total color difference ΔE.

[0074] Light transmittance test: tested according to GB / T 2410-2008 standard.

[0075] Example 1

[0076] The silicon wafer and mobile phone screen were placed in a vacuum deposition chamber. 20g of parylene N powder was loaded into the sublimation chamber. Perfluoropolyether methacrylate was added to the organic monomer feed tank. The valve connecting the parylene cracking furnace and the chamber was opened. The chamber and the cracking furnace were continuously evacuated to below 20mTorr. The chamber temperature was kept at 48°C.

[0077] After the pressure in the vacuum deposition chamber stabilizes, the pyrolysis chamber and sublimation chamber are heated to 650°C and 145°C, respectively. Parylene N powder is sublimated and pyrolyzed before being introduced into the vacuum deposition chamber. Simultaneously, perfluoropolyether methacrylate is vaporized at 120°C at a monomer flow rate of 50 μl / min and introduced into the vacuum deposition chamber. It reacts chemically with the pyrolyzed parylene active monomer molecules and is deposited on the surfaces of the silicon wafer and mobile phone screen substrate.

[0078] After 2 hours, deposition was completed. The monomer feed and the parylene powder feed system were shut down, compressed air was introduced, and the chamber returned to normal pressure. The vacuum chamber was opened, and the silicon wafer and mobile phone screen substrate were removed. The coating thickness and water drop angle of the coated silicon wafer were tested. The color difference and transmittance of the coated mobile phone screen are listed in Table 1.

[0079] Example 2

[0080] Place the silicon wafer and mobile phone screen in a vacuum deposition chamber, put 20g of Parylene N powder into the sublimation chamber, and Add perfluoropolyether to the organic monomer feed tank, open the valve at the connection between the parylene cracking furnace and the chamber, and continuously evacuate the chamber and the cracking furnace to below 20mTorr. The chamber temperature is 48°C.

[0081] After the pressure in the vacuum deposition chamber is stabilized, the pyrolysis chamber and sublimation chamber are heated to 650℃ and 145℃ respectively, and the parylene N powder is introduced into the vacuum deposition chamber after sublimation and pyrolysis. At the same time, the monomer flow rate is 70ul / min. After being vaporized at 120°C, the perfluoropolyether is introduced into a vacuum deposition chamber, where it reacts chemically with the cracked parylene active monomer molecules and is deposited on the surface of the silicon wafer and mobile phone screen substrate.

[0082] After 2 hours, deposition was completed. The monomer feed and the parylene powder feed system were shut down, compressed air was introduced, and the chamber returned to normal pressure. The vacuum chamber was opened, and the silicon wafer and mobile phone screen substrate were removed. The coating thickness and water drop angle of the coated silicon wafer were tested. The color difference and transmittance of the coated mobile phone screen are listed in Table 1.

[0083] Example 3

[0084] Place the silicon wafer and mobile phone screen in a vacuum deposition chamber, and put 20g of Parylene N powder into the sublimation chamber. Add perfluoropolyether to the organic monomer feed tank, open the valve at the connection between the parylene cracking furnace and the chamber, and continuously evacuate the chamber and the cracking furnace to below 20mTorr. The chamber temperature is 48°C.

[0085] After the pressure in the vacuum deposition chamber is stabilized, the pyrolysis chamber and sublimation chamber are heated to 650℃ and 145℃ respectively. After sublimation and pyrolysis, the Parylene N powder is introduced into the vacuum deposition chamber. At the same time, the monomer flow rate is 75ul / min. After being vaporized at 120°C, the perfluoropolyether is introduced into a vacuum deposition chamber, where it reacts chemically with the cracked parylene active monomer molecules and is deposited on the surface of the silicon wafer and mobile phone screen substrate.

[0086] After 2 hours, deposition was completed. The monomer feed and the parylene powder feed system were shut down, compressed air was introduced, and the chamber returned to normal pressure. The vacuum chamber was opened, and the silicon wafer and mobile phone screen substrate were removed. The coating thickness and water drop angle of the coated silicon wafer were tested. The color difference and transmittance of the coated mobile phone screen are listed in Table 1.

[0087] Comparative Example 1

[0088] Place the silicon wafer and mobile phone screen in a vacuum deposition chamber, add 20g of parylene N powder into the sublimation chamber, open the valve at the connection between the parylene cracking furnace and the chamber, and continuously evacuate the chamber and cracking furnace to below 20mTorr. The chamber temperature is 48℃.

[0089] After the pressure in the vacuum deposition chamber stabilizes, the pyrolysis chamber and sublimation chamber are heated to 650°C and 145°C, respectively. After sublimation and pyrolysis, the Parylene N powder is introduced into the vacuum deposition chamber for chemical reaction and deposition on the surface of the silicon wafer and mobile phone screen substrate.

[0090] After 2 hours of deposition, the parylene powder feeding system was closed and compressed air was introduced to return the chamber to normal pressure. The vacuum chamber was opened, and the silicon wafer and mobile phone screen substrate were removed. The coating thickness and water drop angle of the silicon wafer after coating were tested. The color difference and transmittance of the mobile phone screen after coating are listed in Table 1.

[0091] Comparative Example 2

[0092] The silicon wafer and mobile phone screen were placed in a vacuum deposition chamber. The organic monomer perfluoropolyether methacrylate was added to the organic monomer feed tank. The chamber was continuously evacuated to below 20 mTorr, and the chamber temperature was 48°C.

[0093] After the pressure in the vacuum deposition chamber stabilized, perfluoropolyether methacrylate was vaporized at 120°C at a monomer flow rate of 50 μl / min and introduced into the vacuum deposition chamber, where it was deposited on the surfaces of the silicon wafer and the mobile phone screen substrate.

[0094] After 2 hours, the deposition was completed, the monomer feed was turned off, compressed air was introduced, and the chamber returned to normal pressure. The vacuum chamber was opened, and the silicon wafer and mobile phone screen substrate were removed. The coating thickness and water drop angle of the silicon wafer after coating were tested. The color difference and transmittance of the mobile phone screen after coating are listed in Table 1.

[0095] Comparative Example 3

[0096] The silicon wafer and mobile phone screen were placed in a vacuum deposition chamber. 20g of parylene N powder and 6.3g of perfluoropolyether methacrylate were loaded into the sublimation chamber. The valve connecting the parylene cracking furnace and the chamber was opened. The chamber and the cracking furnace were continuously evacuated to below 20mTorr. The chamber temperature was kept at 48°C.

[0097] After the pressure in the vacuum deposition chamber stabilizes, the pyrolysis chamber and sublimation chamber are heated to 650°C and 145°C, respectively. After sublimation and pyrolysis, parylene N powder and perfluoropolyether methacrylate are introduced into the vacuum deposition chamber for chemical reaction and deposition on the surface of the silicon wafer and mobile phone screen substrate.

[0098] After 2 hours of deposition, the parylene powder feeding system was closed and compressed air was introduced to return the chamber to normal pressure. The vacuum chamber was opened, and the silicon wafer and mobile phone screen substrate were removed. The coating thickness and water drop angle of the silicon wafer after coating were tested. The color difference and transmittance of the mobile phone screen after coating are listed in Table 1.

[0099] Table 1 Test results of Examples 1-3 and Comparative Examples 1-3

[0100] As can be seen from the results in Table 1 above, compared with Comparative Example 1, the polymer coatings deposited on the substrate surface by chemical reaction of the parylene active monomer after pyrolysis with the perfluoropolyether organic monomer in Examples 1-3 can greatly improve the hydrophobicity of the parylene coating. As can be seen from the results of Example 1 and Comparative Examples 2-3, the polymer coatings deposited on the substrate surface by chemical reaction of the parylene (parylene N powder) active monomer after pyrolysis with the perfluoropolyether organic monomer (perfluoropolyether methacrylate) have better hydrophobicity than the coatings deposited on the substrate surface by the perfluoropolyether organic monomer (perfluoropolyether methacrylate) alone or the polymer coatings deposited on the substrate surface by chemical reaction after pyrolysis of the perfluoropolyether organic monomer (perfluoropolyether methacrylate) and parylene (parylene N powder).

[0101] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the claims.

Claims

1. A coating, characterized in that: The coating is a polymerized coating deposited on the surface of the substrate by chemical reaction between gaseous organic monomers and parylene active monomers after high-temperature cracking, and the organic monomers include perfluoropolyether and / or perfluoropolyether derivatives.

2. The coating according to claim 1, characterized in that The perfluoropolyether or perfluoropolyether derivative has a structure shown in the following formula (1): In formula (1), R1 is a hydrogen atom, a halogen atom, a C1-C4 hydrocarbon group, a C1-C4 halogenated hydrocarbon group, a hydroxyl group, a carboxyl group, an isocyanate group, an ester group, or a group represented by the following formula (2) or (3), R2 and R3 are independently selected from a linker, an amide group, a sulfonyl group, a carbamate group, a C1-C4 alkylene group, a C1-C4 halogenated alkylene group, a C 6-20 At least one of an arylene group or a group of the following formula (4), R4 is a hydrogen atom, a halogen atom, a C1-C4 alkyl group, a C1-C4 haloalkyl group, a hydroxyl group, a carboxyl group, an isocyanate group, an ester group or -COF, n is an integer from 1 to 10, m is an integer from 1 to 200, and m C n F 2n The O groups are independent of each other. In formula (2), R5, R6 and R7 are independently selected from hydrogen atoms, C1-C 10 Alkyl or C1-C 10 In formula (3), R8, R9 and R 10 are independently selected from hydrogen atoms, halogen atoms Sub, C1-C 10 Alkyl, C1-C 10 haloalkyl, C1-C 10 Alkoxy or C1-C 10 wherein X is O, S or NH, k is an integer from 1 to 10, j is an integer from 1 to 20, and j C k F 2k The O groups are independent of each other.

3. The coating according to claim 2, characterized in that In formula (1), R1 is a fluorine atom, a C1-C4 perfluoroalkyl group, a hydroxyl group, a carboxyl group, a group represented by formula (2) or formula (3), R2 and R3 are independently selected from a connecting bond, a C1-C2 alkylene group, a C1-C2 perfluoroalkylene group or a group represented by formula (4), R4 is a fluorine atom, a C1-C4 perfluoroalkyl group, a hydroxyl group, a carboxyl group or -COF, n is an integer of 1 to 3, and m is an integer of 5 to 50. In formula (2), R5, R6 and R7 are independently selected from hydrogen atoms or methyl groups. In formula (3), R8 is a C1-C4 alkyl group or a C1-C4 alkoxy group. R9 and R 10 They are independently selected from a hydrogen atom, a C1-C4 alkyl group or a C1-C4 alkoxy group. In formula (4), k is an integer of 1 to 4, and j is an integer of 1 to 4.

4. The coating according to claim 2, characterized in that The R1 is a fluorine atom or a C1-C4 perfluoroalkyl group, R2 and R3 are connecting bonds or a C1-C2 perfluoroalkylene group, and R4 is a fluorine atom, -COF or a C1-C4 perfluoroalkyl group.

5. The coating according to claim 2, characterized in that R1 and R4 are hydroxyl groups, and R2 and R3 are independently selected from at least one of a C1-C4 alkylene group and a group of formula (4).

6. The coating according to claim 2, characterized in that R1 is a carboxyl group or a group represented by formula (2), R2 is a connecting bond, or at least one of a C1-C4 alkylene group and a group represented by formula (4), R3 is a connecting bond, and R4 is a fluorine atom or a C1-C4 perfluoroalkyl group.

7. The coating according to claim 1, characterized in that The mass ratio of the parylene active monomer to the perfluoropolyether and / or perfluoropolyether derivative is 10:1 to 1:

10.

8. The coating according to claim 7, characterized in that The mass ratio of the parylene active monomer to the perfluoropolyether and / or perfluoropolyether derivative is 5:1 to 5:

1.

9. The coating according to claim 1, characterized in that The parylene is at least one of parylene N powder, C powder, D powder, F powder or HT powder.

10. A method for preparing a coating according to any one of claims 1 to 9, characterized in that: include: Providing a substrate, and placing the substrate in a vacuum deposition chamber; Introducing gaseous organic monomers and parylene active monomers after high-temperature cracking into the vacuum deposition chamber; The organic monomer and the parylene active monomer react in a vacuum deposition chamber to form the coating on the surface of the substrate.

11. A device, characterized in that: At least part of the surface of the device has the coating according to any one of claims 1 to 9.

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