A protective coating and a method for producing the same

Abstract

The embodiment of the present application provides a protective coating and a preparation method thereof, the protective coating is formed by plasma polymerization coating on the surface of an electronic device, an electrical device, an electronic component or an electrical component, the protective coating is formed by plasma of monomer alpha with a double acrylate structure and monomer beta with more than three carbon-carbon unsaturated bonds, the mass fraction of the monomer beta accounts for 10-35% of the total monomer, and the protective coating can effectively prevent the electronic device, the electrical device, the electronic component or the electrical component from short circuit and failure in a humid or water environment.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of plasma chemistry, and particularly relates to a protective coating and a preparation method thereof. BACKGROUND

[0002] For electronic devices, electrical devices, electronic components or electrical components, moisture is the most common and most important factor that reduces their service life. Moisture is easy to form a path between the device pins, causing device short circuit; long-term exposure to moisture environment can easily cause the device to rust, resulting in line circuit break. In addition, electronic devices, electrical devices, electronic components or electrical components are prone to short circuit and failure when used in water splashing, water splashing, water immersion and underwater environment.

[0003] The protective coating is an important protective measure to protect electronic devices, electrical devices, electronic components or electrical components, such as PCB (printed board assembly), from the effects of moisture, salt spray and mold. In order to improve the protection of the PCB board, the application of the coating will usually reduce the heat dissipation efficiency of the electronic components, and even reduce the fidelity and transmission rate of high-frequency signals. The preparation of polymer protective coating on the surface of the substrate by vapor deposition method is the mainstream method, which is economical and easy to operate. Especially the plasma chemical vapor deposition, which uses plasma to activate the monomer gas and deposits on the surface of the substrate. The polymer protective coating deposited by this method is uniform, which can effectively deposit ultra-thin, transparent and insulating anti-aging plasma polymer coating, and selectively protect electronic devices, electrical devices, electronic components or electrical components, especially printed circuit boards. At present, there are studies on the formation of hydrophobic and oleophobic protective coating on the surface of electronic devices, electrical devices, electronic components or electrical components by plasma chemical vapor deposition of different monomers, but further improvement is needed for the short circuit protection caused by moisture or water environment. SUMMARY

[0004] The specific embodiment of the present application provides a protective coating for avoiding the short circuit and failure of electronic devices, electrical devices, electronic components or electrical components in a moisture or water environment, and the specific scheme is as follows:

[0005] A protective coating, the protective coating is a plasma polymer coating formed by plasma containing monomer alpha and monomer beta on the surface of electronic devices, electrical devices, electronic components or electrical components;

[0006] Among them, the monomer alpha has the structure shown in the following formula (1), and the monomer beta has three or more carbon-carbon unsaturated bonds,

[0007]

[0008] In the above formula (1), A is a connecting part, R1, R2, R3, R4, R5 and R6 are independently selected from hydrogen atom, C1-C10 Alkyl or C1-C 10 The halogen atom replaces the alkyl group;

[0009] The monomer β accounts for 10-35% of the total monomer mass.

[0010] Optionally, the monomer α has the structure shown in formula (2).

[0011]

[0012] In equation (2) above, R7 is C2-C 10 alkylene or C2-C 10 The halogen atom is substituted with an alkylene group, where n is an integer from 1 to 10.

[0013] Optionally, R1, R2, R3, R4, R5 and R6 are each independently selected from hydrogen atoms or methyl groups.

[0014] Optionally, the monomer α is selected from at least one of 1,6-hexanediol dimethacrylate, diethylene glycol dimethacrylate, ethylene glycol dimethacrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, 1,4-butanediol diacrylate, or neopentyl glycol diacrylate.

[0015] Optionally, the monomer α is 1,6-hexanediol diacrylate.

[0016] Optionally, the monomer β has the structure shown in formula (3).

[0017]

[0018] In equation (3) above, R8 is a hydrogen atom, C1-C 10 Alkyl groups, or C1-C groups substituted with hydroxyl or halogen atoms 10 Alkyl groups, R9, R 10 and R 11 Selected independently from C1-C 10 alkylene or C1-C 10 The halogen atom is substituted for the alkylene group, R 12 R 13 and R 14 Each independently selected from C2-C 10 alkylene or C2-C 10 The halogen atom is substituted for the alkylene group, R 15 R 16 R 17 R 18 R 19 R 20 R 21 R22 and R 23 are each independently selected from the group consisting of a hydrogen atom, a C1-C4 alkyl group or a C1-C4 halo-substituted alkyl group, and m1, m2 and m3 are each independently selected from the group consisting of an integer from 0 to 10. 10 10

[0019] Optionally, R8 is a C1-C4 alkyl group or a C1-C4 hydroxyalkyl group, R9, R 10 and R 11 are each independently selected from the group consisting of a C1-C4 alkylene group, R 12 , R 13 and R 14 are each independently selected from the group consisting of a C2-C8 alkylene group, R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 and R 23 are each independently selected from the group consisting of a hydrogen atom or a methyl group, and m1, m2 and m3 are each independently selected from the group consisting of an integer from 0 to 2.

[0020] Optionally, the monomer β is selected from at least one of pentaerythritol triacrylate, 2,6-dimethyl-2,4,6-octatriene, triallyl isocyanurate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane triacrylate or glyceryl trihydroxypropyl ether triacrylate.

[0021] Optionally, the monomer β is pentaerythritol triacrylate, trimethylolpropane trimethacrylate or ethoxylated trimethylolpropane triacrylate.

[0022] Optionally, the electronic device, the electrical device, the electronic component or the electrical component protected by the protective coating is connected to an alternating current power supply of 20.5 V, is placed in tap water to be turned on, and the current is measured, and the holding time of the current of 0.6 A or less is 10 hours or more.

[0023] Optionally, the electronic device, the electrical device, the electronic component or the electrical component is a PCB board.

[0024] Optionally, the thickness of the protective coating is 200-3000 nm.

[0025] A method for preparing any of the above-mentioned protective coatings, comprising:

[0026] forming the protective coating on at least part of the surface of the electronic device, the electrical device, the electronic component or the electrical component by plasma deposition coating.​​

[0027] Optionally, the plasma is a pulsed plasma.

[0028] Optionally, the pulsed plasma is generated by discharging a pulsed voltage, wherein the pulse duty cycle is 0.1-70%, the pulse frequency is 10-500Hz, the repetition frequency is 20Hz-10kHz, the discharge power is 10-400W, and the discharge time is 600-7200s.

[0029] An electronic device, an electrical device, an electronic component, or an electrical component, at least part of a surface of which has the protective coating of any of the above.

[0030] The protective coating and the method for preparing the same according to the embodiment of the present application, the protective coating is formed by plasma polymerization of a plasma of monomer α having a diacrylate structure and monomer β having three or more carbon-carbon unsaturated bonds, which accounts for 10-35% of the total monomer mass fraction, on the surface of an electronic device, an electrical device, an electronic component, or an electrical component, and the protective coating can effectively protect the electronic device, the electrical device, the electronic component, or the electrical component from short circuit and failure in a humid or water environment. EMBODIMENT

[0031] The embodiment of the present application provides a protective coating, which is formed by plasma polymerization of a plasma containing monomer α and monomer β on the surface of an electronic device, an electrical device, an electronic component, or an electrical component.

[0032] The monomer α has the structure shown in the following formula (1), and the monomer β has three or more carbon-carbon unsaturated bonds.

[0033]

[0034] In the above formula (1), A is a connecting moiety, R1, R2, R3, R4, R5, and R6 are each independently selected from a hydrogen atom, a C1-C6 alkyl group, or a C1-C6 halogen-substituted alkyl group. 10 10

[0035] The monomer β accounts for 10-35% of the total monomer mass fraction.

[0036] ​​The protective coating of the embodiment of the present application is formed by plasma of monomer α with double acrylate and monomer β with three or more carbon-carbon unsaturated bonds on the surface of electronic equipment, electrical equipment, electronic components or electrical components to form a high cross-linking degree plasma polymerization coating, which can effectively prevent the electronic equipment, electrical equipment, electronic components or electrical components from short circuit and failure in a humid or water environment. The mass fraction of the monomer β in the total monomers is preferably 10-35%. The content of the monomer β is too high or too low, which is not conducive to the effective protection of the electronic equipment, electrical equipment, electronic components or electrical components from short circuit in a humid or water environment. When the mass fraction of the monomer β in the total monomers is too high, it is easy to cause too large viscosity and gelation, resulting in poor protective performance of the coating. When the mass fraction of the monomer β in the total monomers is too low, it is difficult to form an effective high cross-linking degree protective coating.

[0037] In some embodiments of the protective coating of the embodiment of the present application, R1, R2, R3, R4, R5 and R6 are independently selected from hydrogen atom or methyl group.

[0038] In the protective coating of the embodiment of the present application, A is a connecting part, which can be, for example, alkylene, substituted alkylene, alkylene with O or S atom or carbonyl between carbon-carbon connecting bonds, etc. In some embodiments, the monomer α has the structure shown in the following formula (2).

[0039]

[0040] In the above formula (2), R7 is C2-C 10 alkylene or C2-C 10 halogen atom substituted alkylene, and n is an integer from 0 to 10, specifically 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.

[0041] In the protective coating of the embodiment of the present application, the alkyl group includes straight chain alkyl group, such as methyl, ethyl, propyl or butyl, etc., or branched chain alkyl group, such as isopropyl or isobutyl, etc., and the alkylene group includes straight chain alkylene group, such as methylene, ethylene, propylene or butylene, etc., or branched chain alkylene group, such as isopropylene or isobutylene, etc.

[0042] In some embodiments of the protective coating of the embodiment of the present application, the monomer α is at least one selected from 1,6-hexanediol dimethacrylate, diethyleneglycol dimethacrylate, ethyleneglycol dimethacrylate, tripropyleneglycol diacrylate, 1,6-hexanediol diacrylate, 1,4-butanediol diacrylate or neopentylglycol diacrylate. In some embodiments, the monomer α is 1,6-hexanediol diacrylate.

[0043] The protective coating of this invention, in a specific embodiment, has monomer β having three or more carbon-carbon unsaturated bonds, including carbon-carbon double bonds and carbon-carbon triple bonds. In some specific embodiments, monomer β has three carbon-carbon unsaturated bonds. Specifically, monomer β is selected from at least one of pentaerythritol triacrylate, 2,6-dimethyl-2,4,6-octtriene, triallyl isocyanate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane triacrylate, or glycerol trihydroxypropyl ether triacrylate. In some specific embodiments, monomer β is pentaerythritol triacrylate, trimethylolpropane trimethacrylate, or ethoxylated trimethylolpropane triacrylate.

[0044] In some specific embodiments of the protective coating of the present invention, the monomer β has the structure shown in formula (3).

[0045]

[0046] In equation (3) above, R8 is a hydrogen atom, C1-C 10 Alkyl groups, or C1-C groups substituted with hydroxyl or halogen atoms 10 Alkyl groups, R9, R 10 and R 11 Selected independently from C1-C 10 alkylene or C1-C 10 The halogen atom is substituted for the alkylene group, R 12 R 13 and R 14 Each independently selected from C2-C 10 alkylene or C2-C 10 The halogen atom is substituted for the alkylene group, R 15 R 16 R 17 R 18 R 19 R 20 R 21 R 22 and R 23 Each atom is independently selected from hydrogen atoms, C1-C 10 Alkyl or C1-C 10 The halogen atom replaces the alkyl group, and m1, m2 and m3 are each independently selected from integers from 0 to 10, specifically 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.

[0047] In some specific embodiments of the protective coating of the present invention, R8 is a C1-C4 alkyl or C1-C4 hydroxyalkyl, and R9, R... 10 and R11 each independently selected from the group consisting of C1-C4 alkylene, R 12 , R 13 , and R 14 each independently selected from the group consisting of C2-C8 alkylene, R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 , and R 23 each independently selected from the group consisting of hydrogen atom or methyl group, m1, m2 and m3 are each independently selected from the group consisting of integers from 0 to 2.

[0048] The protective coating of the embodiment of the present application, the electronic device, electrical device, electronic component or electrical component with the protective coating is connected to 20.5V AC power supply, placed in tap water to conduct, the current is measured, the current is 0.6A or less, the holding time is 10 hours or more.

[0049] The protective coating of the embodiment of the present application, the monomer β accounts for 10-35% of the total monomer mass fraction, for example, can be 10%, 12%, 13%, 14%, 15%, 20%, 25%, 30% or 35% and so on, the specific amount can be adjusted according to the actual requirements, for example, in some embodiments, the electronic device, electrical device, electronic component or electrical component with the protective coating is connected to 20.5V AC power supply, placed in tap water to conduct, the current is measured, the current is 0.6A or less, the holding time is 10 hours or more, the amount of monomer β is adjusted.

[0050] The protective coating of the embodiment of the present application, in some embodiments, the protective coating is a plasma polymerized coating formed by the plasma of monomer α and monomer β, in other embodiments, the protective coating can be a plasma polymerized coating formed by the plasma of monomer α and monomer β plus appropriate other monomers without affecting the overall coating performance of the protective coating.

[0051] The protective coating of the present application embodiment, in some embodiments, the electronic device or electrical device, for example, can be a mobile phone, tablet, keyboard, e-reader, wearable device, display, earphone, USB data line, USB interface, sound transmission net, ear cap or headband, etc., the electronic component or electrical component, for example, can be printed circuit board (PCB), printed circuit board array (PCBA), resistor, capacitor, transistor, diode, amplifier, relay, transformer, battery, fuse, integrated circuit, switch, LED, LED display, piezoelectric element, optoelectronic component or antenna or oscillator, etc.

[0052] The protective coating of the present application embodiment, in some embodiments, the thickness of the protective coating is 200-3000 nm, in some embodiments, the thickness of the protective coating is 400-1000 nm, for example, can be 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm or 1000 nm, etc.

[0053] The present application embodiment also provides a method for preparing the above protective coating, the method comprising:

[0054] The protective coating is formed on at least part of the surface of the electronic device, electrical device, electronic component or electrical component by plasma deposition coating.

[0055] The method for preparing the protective coating of the present application embodiment, the description of monomer α, monomer β, electronic device, electrical device, electronic component or electrical component, etc. is as described above.

[0056] The method for preparing the protective coating of the present application embodiment, in order to further enhance the bonding force of the protective coating and the surface of the electronic device, electrical device, electronic component or electrical component, in some embodiments, the surface of the electronic device, electrical device, electronic component or electrical component is pretreated by continuous or pulsed plasma, for example, the discharge power is 100-600 W, the discharge time is 60-600 s, or the pulse duty cycle is 0.1-70%, the pulse frequency is 10-500 Hz, the discharge power is 10-500 W, and the discharge time is 60-600 s. In some other embodiments, the surface of the electronic device, electrical device, electronic component or electrical component is pretreated by heat, oxygen or high-energy radiation, etc.

[0057] In some embodiments of the method of preparing a protective coating of the present disclosure, the monomer flow rate is 10-2400 ul / min, for example, 10 ul / min, 50 ul / min, 100 ul / min, 200 ul / min, 300 ul / min, 500 ul / min, 1000 ul / min, 1500 ul / min, 2000 ul / min, or 2400 ul / min, etc.; the temperature in the cavity is controlled at 20-80°C, for example, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, or 80°C, etc.; and the monomer vaporization temperature is 50-120°C, for example, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, or 120°C, etc., and the vaporization occurs under vacuum.

[0058] In some embodiments of the method of preparing a protective coating of the present disclosure, the plasma is continuous plasma generated by applying continuous voltage discharge, wherein the discharge power is 10-300 W, for example, 10 W, 50 W, 100 W, 150 W, 200 W, 250 W, or 300 W, and the discharge time is 60-600 s, for example, 60 s, 100 s, 200 s, 300 s, 400 s, 500 s, or 600 s, etc. In some embodiments, the plasma is pulsed plasma generated by applying pulsed voltage discharge, wherein the pulsed power is 10-400 W, for example, 10 W, 50 W, 100 W, 150 W, 200 W, 250 W, 300 W, 350 W, or 400 W, etc.; the pulsed frequency is 10-500 Hz, for example, 10 Hz, 15 Hz, 20 Hz, 25 Hz, 30 Hz, 35 Hz, 40 Hz, 45 Hz, 50 Hz, 100 Hz, 200 Hz, 300 Hz, 400 Hz, or 500 Hz, etc.; the pulsed duty cycle is 0.1%-70%, for example, 0.1%, 0.5%, 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, or 70%, etc.; and the plasma discharge time is 600-7200 s, for example, 600 s, 700 s, 800 s, 900 s, 1000 s, 2000 s, 3000 s, 4000 s, 5000 s, 6000 s, or 7000 s, etc.

[0059] The method for preparing the protective coating in the embodiment of the present application can be any of the existing discharge modes, such as electrodeless discharge (e.g., radio frequency inductive coupling discharge, microwave discharge), single electrode discharge (e.g., plasma jet formed by corona discharge, single electrode discharge), double electrode discharge (e.g., dielectric barrier discharge, bare electrode radio frequency glow discharge), and multi-electrode discharge (e.g., discharge using a floating electrode as a third electrode).

[0060] The embodiment of the present application also provides an electronic device, an electrical device, an electronic component, or an electrical component, at least a part of the surface of which is provided with the protective coating described above, and in some embodiments, a part of the surface or the entire surface of the electronic device, the electrical device, the electronic component, or the electrical component is deposited with the protective coating described above.

[0061] The present application is further described below through specific examples.

[0062] Examples

[0063] Test method description

[0064] Coating thickness test: The test was performed using a US Filmetrics F20-UV-film thickness meter.

[0065] Coating protection performance test: The printed circuit board with the protective coating was connected to a 20.5V AC power supply and placed in running water to determine the current of the circuit board. When the current exceeded 0.6A, it was determined that the printed circuit board was conducting in water, and the conduction time of the circuit board with different high cross-linking degree waterproof coatings was recorded.

[0066] Example 1

[0067] A printed circuit board (PCB board) was placed on a rotating support rotating around the center in a plasma chamber, the chamber was vacuumed to 80 mTorr, helium gas was introduced at a flow rate of 40 seem, the chamber temperature was 50°C, and a plasma continuous discharge was started for pretreatment, the pretreatment discharge power was 60 W, and the discharge was continued for 300 s. Then, monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate was introduced at a mass ratio of 6:1, the monomer vaporization temperature was 110°C, the rotating support and pulsed plasma discharge were started, the pulse duty cycle was 8%, the pulse frequency was 60 Hz, the pulse discharge power was 65 W, the monomer flow rate was 480 μL / min, and the reaction time was 3600 s. After completion, compressed air was filled to restore the chamber to normal pressure, the PCB board was taken out, and points A, B and C were taken at the positions farthest from the axis, the center and the closest position in the rotating support for coating thickness testing, the results of which are listed in Table 1 below. The coating protection performance of positions A, B and C was tested, and the results are listed in Table 2 below.

[0068] Example 2

[0069] Except that monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate was introduced at a mass ratio of 3:1 instead of monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate introduced at a mass ratio of 6:1, other conditions were the same as in Example 1. The PCB board was also taken at points A, B and C at the positions farthest from the axis, the center and the closest position in the rotating support for coating thickness testing, the results of which are listed in Table 1 below. The coating protection performance of positions A, B and C was tested, and the results are listed in Table 2 below.

[0070] Example 3

[0071] Except that monomer gas of 1,6-hexanediol diacrylate and trimethylolpropane trimethacrylate was introduced at a mass ratio of 7:1 instead of monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate introduced at a mass ratio of 6:1, other conditions were the same as in Example 1. The PCB board was also taken at points A, B and C at the positions farthest from the axis, the center and the closest position in the rotating support for coating thickness testing, the results of which are listed in Table 1 below. The coating protection performance of positions A, B and C was tested, and the results are listed in Table 2 below.

[0072] Example 4

[0073] Except for replacing the monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate by mass ratio 6:1 with the monomer gas of 1,6-hexanediol diacrylate and pentaerythritol triacrylate by mass ratio 5:1, other same as example 1, also take the PCB board in the turret farthest from the axis, the center position and the nearest position respectively as points A, B and C for coating thickness test, the results are listed in the following table 1, compare the coating protection performance test of A, B and C positions, the results are listed in the following table 2.

[0074] Example 5

[0075] Except for replacing the monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate by mass ratio 6:1 with the monomer gas of 1,6-hexanediol diacrylate and pentaerythritol triacrylate by mass ratio 3:1, other same as example 1, also take the PCB board in the turret farthest from the axis, the center position and the nearest position respectively as points A, B and C for coating thickness test, the results are listed in the following table 1, compare the coating protection performance test of A, B and C positions, the results are listed in the following table 2.

[0076] Comparative example 1

[0077] Except for replacing the monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate by mass ratio 6:1 with only the monomer gas of 1,6-hexanediol diacrylate, other same as example 1, also take the PCB board in the turret farthest from the axis, the center position and the nearest position respectively as points A, B and C for coating thickness test, the results are listed in the following table 1, compare the coating protection performance test of A, B and C positions, the results are listed in the following table 2.

[0078] Comparative example 2

[0079] Except for replacing the monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate by mass ratio 6:1 with the monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate by mass ratio 3:2, other same as example 1, also take the PCB board in the turret farthest from the axis, the center position and the nearest position respectively as points A, B and C for coating thickness test, the results are listed in the following table 1, compare the coating protection performance test of A, B and C positions, the results are listed in the following table 2.

[0080] Comparative example 3

[0081] Except for the monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate with a mass ratio of 6:1 was replaced by the monomer gas of diethylene glycol divinyl ether and ethoxylated trimethylolpropane triacrylate with a mass ratio of 3:1, other same as example 1, the PCB board was taken points A, B and C respectively at the farthest position, the center position and the nearest position of the off-axis in the turntable for coating thickness test, the results were listed in the following table 1, and the coating protection performance test was carried out at the positions A, B and C, and the results were listed in the following table 2.

[0082] Comparative example 4

[0083] Except for the monomer gas of 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate with a mass ratio of 6:1 was replaced by the monomer gas of diethylene glycol divinyl ether and ethoxylated trimethylolpropane triacrylate with a mass ratio of 3:1, other same as example 1, the PCB board was taken points A, B and C respectively at the farthest position, the center position and the nearest position of the off-axis in the turntable for coating thickness test, the results were listed in the following table 1, and the coating protection performance test was carried out at the positions A, B and C, and the results were listed in the following table 2.

[0084] Table 1, coating thickness test results of example 1-2 and comparative example 1-5

[0085]

[0086] Table 2, coating protection performance test results of example 1-2 and comparative example 1-5

[0087] A position on time / h B position on time / h C position on time / h Example 1 22.0 31.0 36.0 Example 2 15.6 14.5 14.3 Example 3 10.3 9.6 10.8 Example 4 22.5 18.0 32.5 Example 5 16.7 15.0 14.8 Comparative Example 1 7.5 7.0 7.2 Comparative Example 2 5.1 4.8 6.0 Comparative Example 3 0 0 0 Comparative Example 4 0 0 0

[0088] From the coating thickness test results in Table 1 and the coating protection performance test results in Table 2, compared with the PCB board of Comparative Example 1 in which only 1,6-hexanediol diacrylate was passed, the conduction time of the PCB board of Example 1 in which 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate were passed in a mass ratio of 6:1 was increased to about 22 hours, the conduction time of the PCB board of Example 2 in which 1,6-hexanediol diacrylate and ethoxylated trimethylolpropane triacrylate were passed in a mass ratio of 3:1 was increased to about 14 hours, the conduction time of the PCB board of Example 3 in which 1,6-hexanediol diacrylate and trimethylolpropane trimethylacrylate were passed in a mass ratio of 7:1 was increased to about 10 hours, the conduction time of the PCB board of Example 4 in which 1,6-hexanediol diacrylate and pentaerythritol triacrylate were passed in a mass ratio of 5:1 was increased to about 20 hours, and the conduction time of the PCB board of Example 5 in which 1,6-hexanediol diacrylate and pentaerythritol triacrylate were passed in a mass ratio of 3:1 was increased to about 15 hours, indicating that the addition of ethoxylated trimethylolpropane triacrylate, trimethylolpropane trimethylacrylate and pentaerythritol triacrylate having three unsaturations can effectively improve the underwater protection capability of the film layer on the printed circuit board. However, when the content of ethoxylated trimethylolpropane triacrylate monomer was increased to 40%, the underwater protection performance decreased, for example, the conduction time of the PCB board in Comparative Example 2 was reduced to about 5 hours. When only ethoxylated trimethylolpropane triacrylate monomer or ethoxylated trimethylolpropane triacrylate monomer and diethylene glycol divinyl ether were used to form the plasma protection coating, as in Comparative Examples 3 and 4, the coating thickness was greatly reduced under the same conditions, and an effective protection coating could not be formed. In the protection performance test, the PCB board was conductioned instantly and almost had no underwater protection capability.

[0089] Although the present application has been disclosed as above, the present application is not limited to this. Any person skilled in the art can make various modifications and changes without departing from the spirit and scope of the present application, and the protection scope of the present application should be defined by the scope defined in the claims.

Claims

1. A protective coating, characterized in that, The protective coating is formed by plasma polymerization of a plasma of monomer alpha and monomer beta on the surface of an electronic device, an electrical device, an electronic component or an electrical component; The monomer alpha has a structure shown in formula (1) below, and the monomer beta has three or more carbon-carbon unsaturated bonds, ， （1） In the above formula (1), A is a linking moiety, R1, R2, R3, R4, R5and R6are each independently selected from a hydrogen atom, a C1-C 10 alkyl group or a C1-C 10 halogen atom-substituted alkyl group; The monomer beta has a structure shown in formula (3) below, ， （3） In the above formula (3), R8is a hydrogen atom, a C1-C 10 alkyl group, or a C1-C 10 alkyl group having a hydroxyl group or a halogen atom substituted thereon, R9, R 10 and R 11 are each independently selected from a bond, a C1-C 10 alkylene group, or a C1-C 10 halogen atom substituted alkylene group, R 12 , R 13 and R 14 are each independently selected from a C2-C 10 alkylene group, or a C2-C 10 halogen atom substituted alkylene group, R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 and R 23 are each independently selected from a hydrogen atom, a C1-C 10 alkyl group, or a C1-C 10 halogen atom substituted alkyl group, m1, m2 and m3 are each independently selected from an integer of 0 to 10; The monomer beta accounts for 10-35% of the total monomer mass fraction; The electronic device, the electrical device, the electronic component or the electrical component protected by the protective coating is connected to an alternating power supply of 20.5V, and the current is measured when the electronic device, the electrical device, the electronic component or the electrical component is turned on in tap water. The holding time of the current of 0.6A or less is 10 hours or more.

2. The protective coating of claim 1, wherein, The monomer alpha has a structure shown in formula (2) below, ， （2） In the above formula (2), R7is a C2-C 10 alkylene group or a C2-C 10 halogen atom-substituted alkylene group, and n is an integer of 1 to 10.

3. The protective coating of claim 1, wherein, The R1, R2, R3, R4, R5 and R6 are independently selected from a hydrogen atom or a methyl group.

4. The protective coating of claim 3, wherein, The monomer alpha is at least one selected from 1,6-hexanediol dimethacrylate, diethylene glycol dimethacrylate, ethylene glycol dimethacrylate, tripropyleneglycol diacrylate, 1,6-hexanediol diacrylate, 1,4-butanediol diacrylate or neopentyl glycol diacrylate.

5. The protective coating according to claim 4, characterized in that The monomer alpha is 1,6-hexanediol diacrylate.

6. The protective coating of claim 1, wherein, R8is a C1-C4alkyl or a C1-C4hydroxyalkyl, R9, R 10 and R 11 are each independently selected from a C1-C4alkylene, R 12 , R 13 , and R 14 are each independently selected from a C2-C8alkylene, R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 and R 23 are each independently selected from a hydrogen atom or a methyl group, and m1, m2, and m3 are each independently selected from an integer of 0 to 2.

7. The protective coating of claim 1, wherein, The monomer beta is pentaerythritol triacrylate, trimethylolpropane trimethacrylate or ethoxylated trimethylolpropane triacrylate.

8. The protective coating of claim 1, wherein, The electronic device, the electrical device, the electronic component or the electrical component is a PCB board.

9. The protective coating of claim 1, wherein, The thickness of the protective coating is 200-3000nm.

10. A method for producing the protective coating according to any one of claims 1 to 9, characterized in that Comprising: The protective coating is formed on at least part of the surface of the electronic device, the electrical device, the electronic component or the electrical component by plasma deposition coating.

11. The method of claim 10, wherein the protective coating is prepared by, The plasma is a pulsed plasma.

12. The method of claim 11, wherein the protective coating is prepared by, The pulsed plasma is generated by applying a pulsed voltage discharge, wherein the pulse duty cycle is 0.1-70%, the pulse frequency is 10-500Hz, the discharge power is 10-400W, and the discharge time is 600s-7200s.

13. An electronic device, an electrical device, an electronic component, or an electrical component, characterized by comprising the compound according to any one of claims 1 to 12. At least part of the surface of the electronic device, the electrical device, the electronic component or the electrical component has the protective coating according to any one of claims 1-9.

Images