WO2019037443A1

WO2019037443A1 - Preparation method for organosilicon hard nano-protective coating

Info

Publication number: WO2019037443A1
Application number: PCT/CN2018/082832
Authority: WO
Inventors: 宗坚
Original assignee: 江苏菲沃泰纳米科技有限公司
Priority date: 2017-08-23
Filing date: 2018-04-12
Publication date: 2019-02-28
Also published as: CN107523809B; CN107523809A

Abstract

A preparation method for an organosilicon hard nano-protective coating, belonging to the field of plasma technology. In the method, the vacuum degree within a reaction chamber is adjusted, an inert gas is introduced, a base material is caused to move, a monomer vapour is introduced for chemical vapour deposition, and an organosilicon nano-coating is prepared via chemical vapour deposition on a surface of the base material. The monomer vapour component is a mixture of at least one organosilicon monomer containing a double bond, Si-Cl, Si-O-C, Si-N-Si or Si-O-Si structure or an annular structure and at least one polyfunctional unsaturated hydrocarbon or hydrocarbon derivative. The introduction of the monomer vapour is stopped, and oxygen and/or water vapour is introduced for hardening the surface of the organosilicon nano-coating. The present invention replaces traditional carbon/hydrogen/oxygen organic compound monomers with the organosilicon monomer, wherein each silicon atom at least provides 1-4 active sites for higher activity. A portion of oxygen is introduced into the monomer, the organosilicon is oxidised to nano-silicon dioxide, and the coating hardness is significantly increased by a dispersion strengthening effect.

Description

Method for preparing silicone hard nano protective coating

Technical field

The invention belongs to the technical field of plasma chemical vapor deposition, and in particular relates to a preparation method of a silicone nano protective coating.

Background technique

Anti-mold, anti-moist and anti-salt spray (referred to as three-proof) is an important problem that needs to be solved in the process of storage, transportation and use of electronic devices. Mold, salt spray and moisture often cause electronic devices to fail due to short circuits. Therefore, applying a protective coating on the surface of electronic products is an important method to improve the service life of electronic products. As the variety of electronic products continues to increase, more and more electronic devices need to be touched and operated, so that the protective coating is damaged by external force, resulting in a decrease in coating protection performance. Therefore, in addition to the excellent "three-proof" performance, the protective coating applied to the electronics industry must have a certain strength, hardness and wear resistance.

At present, the use of protective coatings to protect electronic products is an effective way to improve the service life of electronic products. There are usually two methods for obtaining a protective coating, a liquid phase method and a gas phase method. The liquid phase method usually adopts three anti-paints. After coating the electronic products, it uses thermal curing or photocuring to form a dense organic coating on the circuit board to protect the circuit boards and related equipment from environmental pollution. . The three anti-paint has good resistance to high and low temperature; it forms a transparent protective film after curing, and has superior properties of insulation, moisture, leakage, shock, dust, corrosion, aging and corona resistance. However, the liquid phase method will produce waste water, waste gas and waste liquid. The solvent used will cause certain damage to the electronic device substrate itself. In addition, the thickness is mostly several tens of micrometers, which is difficult to control at the nanometer level. For some electrons requiring heat dissipation and signal transmission. Device features will have an impact.

The gas phase method includes methods such as vapor deposition and plasma vapor deposition. The most typical vapor deposition coating is a parylene coating, developed by Union Carbide Co. of the United States and widely used in electronic product protection. The parylene coating is a p-xylene polymer that first heats para-xylene to 680 degrees Celsius to form an active para-xylene dimer. After the deposition chamber is lowered in temperature, the dimer is deposited in the electron. On the surface of the product, a polymer film is formed. Since the paraxylene structure is highly symmetrical, the dipole moment is 0, and due to the presence of the benzene ring, the polymer molecule has a large free volume; and at the same time, due to the relatively large molecular weight of the polymer, the coating is dense. Due to the above characteristics, the parylene coating has low water, gas permeability and high barrier effect to achieve moisture, water, rust and acid and alkali corrosion resistance. This parylene is deposited under vacuum and can be used in applications where liquid coatings cannot be involved, such as high frequency circuits and very weak current systems. The thickness of the polymer film coating is the main reason for the protection failure of the para-xylene vapor-deposited conformal coating. The polymer film coating of the printed circuit board component is prone to local rust failure at a thickness of 3 to 7 microns without affecting the high. The coating thickness should be ≥ 30 μm in the case of frequency dielectric loss. Parylene coating requires high pretreatment of printed circuit boards that need protection, such as conductive components, signal transmission components, RF components, etc., in the vapor deposition of conformal coatings, it is necessary to pre-mask the circuit board components to avoid Affects component performance. This drawback has brought great limitations to the application of parylene coating. Pyrene coatings have high cost of raw materials, harsh coating preparation conditions (high temperature, high vacuum requirements), low film formation rate, and thick coatings tend to cause poor heat dissipation, signal blocking, and increased coating defects. In addition, the reactant monomers in this method can only select p-xylene and p-xylene chloride, and the coating structure and function are poorly controllable. Due to the above reasons, it is difficult to widely apply the parylene coating.

In view of the above problems, it is of great value to develop a coating and preparation method which is environmentally friendly, has high hardness and good insulation, and has excellent protection performance under thin coating conditions.

Plasma chemical vapor deposition (PCVD) is a technique in which a reactive gas is activated by a plasma to promote a chemical reaction on a surface of a substrate or a near surface to form a solid film. Plasma chemical vapor deposition coating has the following advantages

(1) It is a dry process that produces a uniform film without pinholes.

(2) The plasma polymerization film is stable in chemical and physical properties such as solvent resistance, chemical corrosion resistance, heat resistance, and abrasion resistance.

(3) The plasma polymerization film has good adhesion to the substrate.

(4) A uniform film can also be formed on the surface of the substrate having irregular irregularities.

(5) The coating preparation temperature is low, and can be carried out under normal temperature conditions, thereby effectively avoiding damage to temperature sensitive devices.

(6) The plasma process can not only prepare a coating having a thickness of a micron order but also can prepare an ultra-thin nano-scale coating.

(7) The coating is highly configurable. Under plasma conditions, most of the organic monomers can be activated into highly active free radicals and form a coating on the surface of the electronic product. The screening and design of the monomer dipole moment, chemical inertness, and free volume is an important strategy for obtaining a coating with good insulation and excellent protection in a thin condition.

(8) The coating structure is highly controllable, and the composition and proportion of the monomer can be changed at any time, so that the coating has a special structure such as multilayer, gradient and modulation.

(9) It is possible to prepare inorganic and organic composite structural coatings.

In the preparation process of the existing plasma chemical vapor deposition coating, the substrate is fixed, and the motion state of the substrate is not related to the discharge energy of the plasma; the stationary substrate is treated by the continuous discharge method. The activated chain scission in the monomer is generally formed into a film by simple stacking under the action of continuous discharge, and the obtained plating layer generally has a loose structure and even a high degree of pulverization, which is disadvantageous to the formation of a microscopic dense structure of the coating layer. Waterproof, moisture-proof, corrosion-resistant, solvent-resistant and other protective properties are poor.

Due to the different regional differences in plasma density and chemical material density in the reaction chamber, the stationary substrate may cause slow deposition of coatings in some areas, low production efficiency, and a large difference in uniformity and compactness.

At present, most plasma coatings are traditional hydrocarbon-hydrogen organic compounds. Compared with these traditional organic coatings, silicone coatings are environmentally friendly, have high hardness, good wear resistance, and good insulation properties. Industry applications are becoming more widespread. The silicone monomer itself is non-toxic and does not decompose into toxic and harmful substances. After polymerization of the monomer, the polymer coating has high silicon due to silicon oxide bond or inorganic SiO ₂ nanoparticles formed in the coating. Hardness, good insulation and heat resistance. However, most silicone coatings are currently obtained by the liquid phase method. The silicone monomer is hydrolyzed in solution to form a sol. The sol is applied to the sample to be processed and finally thermally cured to form a dense coating on the surface of the sample. The thickness of the coating is typically from a few microns to a few microns. Liquid-phase silicone coating technology, although more environmentally friendly than traditional liquid-phase coating technology, has many shortcomings:

(1) It is necessary to use water or organic matter as a solvent, which adversely affects electronic products;

(2) The presence of wastewater, waste liquid and waste gas requires post-treatment;

(3) The thickness of the coating is poorly controllable and difficult to control to the nanometer level.

In addition, organic coatings obtained by plasma deposition, such as fluorocarbon coatings, parylene coatings, etc., usually have a hardness of HB-2H, which is easy to cause damage under touch and scratch conditions, reducing service life. .

Summary of the invention

The present invention provides a method for preparing a silicone hard nano protective coating to solve the above technical problems. In the preparation process, the substrate is kept in motion by the combination of the motion characteristics of the substrate and the plasma discharge energy, and the plasma discharge energy is output. The plasma discharge generates a plasma, and by controlling the relationship between the plasma discharge energy and the bond energy of the monomer, the effective activation of the higher energy active group in the monomer component by the low temperature plasma is obtained, and at the same time, The additional active sites introduced are cross-linked and polymerized in a plasma environment to form a dense network structure.

The present invention replaces a conventional hydrocarbon-hydrogen organic compound monomer with a silicone monomer. Since the functional group attached to the silicon in the silicone monomer is liable to undergo hydrolysis or alcoholysis, the obtained structure is very susceptible to condensation reaction and cross-linking with each other. Each silicon atom provides at least 1-4 active sites and has high activity. Therefore, in the case of low temperature plasma, free radicals are generated and cross-linking reaction occurs, forming a dense cross-linking compound and improving the protective property. The plasma deposition method can achieve precise and controllable coating thickness from nanometer to micrometer, and does not require the use of solvents, and also avoids the shortage of wastewater, waste liquid, exhaust gas, etc. by the liquid phase silicone coating method.

At the same time, partial oxygen is introduced into the monomer to cause oxidation reaction between the oxygen and the silicone monomer. When the oxygen completely replaces the carbon on the silicon atom, the silicone can be oxidized to nano silica. When water vapor is introduced into the monomer, hydrolysis reaction with the silicone can be carried out to produce nano silica. The obtained nano-silica has a mass percentage of about 5% to 20%; since the silica is an atomic crystal and has a hardness of up to 1500 Hv, it is dispersed in the coating layer, and the hardness of the coating can be greatly improved due to the dispersion strengthening effect. The organic coating obtained by plasma deposition usually has a hardness of HB-2H. When the mass percentage of silica in the coating is 5%, the hardness of the coating can be increased to H-3H. When the mass percentage of silica in the coating is 20%, the coating hardness is increased to 2H-4H.

The technical solutions adopted by the present invention are as follows:

A method for preparing a silicone hard nano protective coating, comprising: the following steps:

(1) Pre-processing:

The substrate is placed in a reaction chamber of the nano-coating preparation device, and the reaction chamber is continuously evacuated, and the vacuum in the reaction chamber is pumped to 10 to 200 mTorr, and an inert gas of He, Ar or He and Ar is introduced. Mixing the gas, opening the moving mechanism to cause the substrate to move in the reaction chamber;

(2) Preparation of silicone coating:

Passing monomer vapor into the reaction chamber to a vacuum of 30-300 mTorr, plasma discharge is started, chemical vapor deposition is performed, and a silicone nano-coating is prepared by chemical vapor deposition on the surface of the substrate;

The monomer vapor component comprises:

At least one silicone monomer containing a double bond, a Si-Cl, a Si-OC, a Si-N-Si, a Si-O-Si structure or a cyclic structure, and at least one polyfunctional unsaturated hydrocarbon and a hydrocarbon a mixture of derivatives;

The mass fraction of polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives in the monomer vapor is 15-65%;

The monomer steam is introduced into the reaction chamber by atomizing, volatilizing and introducing the monomer into the reaction chamber by a low pressure of 10 to 200 mTorr, and the flow rate of the monomer is 10 to 1000 μL/min;

(3) Surface hard treatment:

Stop the introduction of the monomer vapor, pass oxygen and/or water vapor, the flow rate is 10 ~ 100μL / min, wherein oxygen and water vapor can be mixed in any ratio, plasma discharge, discharge power is 50-100W, continuous discharge Hard time treatment of the surface of the silicone nano-coating layer for 60s-180s;

(4) Post-processing:

Stop the introduction of the oxygen and/or water vapor, stop the plasma discharge, continue to vacuum, keep the vacuum of the reaction chamber at 10~200 mTorr, and then pass air to an atmospheric pressure after 1 to 5 minutes to stop the substrate. Exercise, then remove the substrate;

Alternatively, stopping the introduction of the oxygen and/or water vapor while stopping the plasma discharge, charging the reaction chamber with air or an inert gas to a pressure of 2000-5000 mTorr, and then evacuating to 10-200 mTorr, The aeration and evacuation steps are performed at least once, the air is introduced to an atmospheric pressure, the movement of the substrate is stopped, and then the substrate is taken out.

In the step (1), the substrate generates motion in the reaction chamber, and the substrate moves in the form of a linear reciprocating motion or a curved motion of the substrate relative to the reaction chamber, the curved motion including circular motion, elliptical motion, planetary motion, Curved motion of spherical motion or other irregular routes.

The substrate in the step (1) is a solid material, and the solid material is an electronic product, an electrical component, an electronic assembly semi-finished product, a PCB board, a metal plate, a polytetrafluoroethylene plate or an electronic component, and the surface of the substrate After preparation of the silicone nano-coating, any interface can be exposed to water environment, mold environment, acid, alkaline solvent environment, acid, alkaline salt spray environment, acidic atmospheric environment, organic solvent soaking environment, cosmetic environment, sweat environment, Use in cold or hot cycle impact environment or wet heat alternating environment.

In the step (1), the reaction chamber is a rotating body chamber or a cubic chamber, the volume of the reaction chamber is 50-1000 L, the temperature of the reaction chamber is controlled at 30-60 ° C, and the inert gas is introduced into the flow. It is 5 to 300 sccm.

In the step (2): plasma discharge, chemical vapor deposition, the plasma discharge process during the deposition process includes low power continuous discharge, pulse discharge or periodic alternating discharge.

The plasma discharge process during the deposition process is a low power continuous discharge, specifically including the following deposition process at least once:

The deposition process includes a pretreatment stage and a coating stage. The plasma discharge power in the pretreatment stage is 150-600 W, the continuous discharge time is 60-450 s, and then enters the coating stage. The plasma discharge power is adjusted to 10 to 150 W, and the continuous discharge time is 600 to 3600 s. .

The plasma discharge process during the deposition is a pulse discharge, specifically including the following deposition process at least once:

The deposition process includes a pretreatment stage and a coating stage. The plasma discharge power of the pretreatment stage is 150-600 W, and the continuous discharge time is 60-450 s, and then enters the coating stage. The coating stage is pulse discharge, the power is 10 to 300 W, and the time is 600 s to 3600 s. The frequency of the pulse discharge is 1 to 1000 Hz, and the duty ratio of the pulse is 1:1 to 1:500.

The plasma discharge process during the deposition process is a periodic alternating discharge, specifically including the following deposition process at least once:

The deposition process includes a pretreatment stage and a coating stage. The plasma discharge power in the pretreatment stage is 150-600 W, and the continuous discharge time is 60-450 s, and then enters the coating stage. The plasma in the coating stage is a periodic alternating discharge output with a power of 10 to 300 W. The time is 600s~3600s, the frequency conversion rate is 1-1000Hz, and the plasma cycle alternately changes. The discharge output waveform is a sawtooth waveform, a sinusoidal waveform, a square wave waveform, a full-wave rectified waveform or a half-wave rectified waveform.

The silicone monomer containing a double bond, a Si—Cl, a Si—O—C, a Si—N—Si, a Si—O—Si structure or a ring structure includes:

Silicone monomer containing double bond structure: allyl trimethoxy silane, vinyl triethoxy silane, vinyl trimethyl silane, 3-butenyl trimethyl silane, vinyl tributyl ketone fluorenyl Silane, tetramethyldivinyldisiloxane, 1,2,2-trifluorovinyltriphenylsilane;

Silicone monomer containing Si-Cl bond: triphenylchlorosilane, methylvinyldichlorosilane, trifluoropropyltrichlorosilane, trifluoropropylmethyldichlorosilane, dimethylphenylchlorosilane , tributylchlorosilane, benzyldimethylchlorosilane;

Silicone monomer containing Si-OC structure: tetramethoxysilane, trimethoxyhydrogensiloxane, n-octyltriethoxysilane, phenyltriethoxysilane, vinyltris(2-methoxy Ethyl ethoxy) silane, triethyl vinyl silane, hexaethylcyclotrisiloxane, 3-(methacryloyloxy)propyl trimethoxy silane, phenyl tris(trimethyl siloxane group Silane, diphenyldiethoxysilane, dodecyltrimethoxysilane, n-octyltriethoxysilane, dimethoxysilane, 3-chloropropyltrimethoxysilane;

Silicone monomer containing Si-N-Si or Si-O-Si structure: hexamethyldisilazide, hexamethylcyclotrisilylamino, hexamethyldisilazane, hexamethyldisiloxane;

Silicone monomer containing cyclic structure: hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, hexaphenylcyclotrisiloxane, decamethylcyclopentasiloxane, octaphenyl ring Tetrasiloxane, triphenylhydroxysilane, diphenyldihydroxysilane, bis(tritylsilyl) chromate, trifluoropropylmethylcyclotrisiloxane, 2,2,4,4 -tetramethyl-6,6,8,8-tetraphenylcyclotetrasiloxane, tetramethyltetravinylcyclotetrasiloxane, 3-glycidoxypropyltriethoxysilane, γ - glycidyloxypropyltrimethoxysilane;

The polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives include:

1,3-butadiene, isoprene, 1,4-pentadiene, ethoxylated trimethylolpropane triacrylate, tripropylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, ethylene glycol diacrylate, diethylene glycol divinyl ether or neopentyl glycol diacrylate.

In the steps (2) and (3), the plasma discharge mode is radio frequency discharge, microwave discharge, intermediate frequency discharge, high frequency discharge, and electric spark discharge, and the waveforms of the high frequency discharge and the intermediate frequency discharge are sinusoidal or double A pole pulse, a radio frequency plasma is a plasma generated by discharge of a high frequency electromagnetic field. The microwave method utilizes the energy of the microwave to excite the plasma, and has the advantages of high energy utilization efficiency. At the same time, since the electrodeless discharge and the plasma are pure, it is an excellent method for high-quality, high-rate, large-area preparation.

During the preparation of the coating, the motion characteristics of the substrate and the plasma discharge energy are combined. During the plasma discharge during the preparation process, the substrate generates motion, improves the deposition efficiency of the coating, and improves the uniformity and compactness of the coating thickness.

The prepared coating has good wear resistance, and has waterproof and moisture proof, mold proof, acid resistance, alkaline solvent, acid and alkali salt spray, acid atmosphere, organic solvent immersion, cosmetics resistance, sweat resistance and resistance. Thermal and thermal cycle impact (-40 ° C ~ +75 ° C), resistance to heat and humidity (humidity 75% ~ 95%) and other characteristics. With the above protective performance, the coating thickness is between 1 and 1000 nm, and the influence on the RF communication signal in the range of 10M to 8G is less than 5%.

The above technical solution of the present invention has the following advantages compared with the prior art:

1. The plasma chemical vapor deposition method is more environmentally friendly than the liquid phase three-coating coating method; and the deposition temperature is lower, the speed is faster, and the coating structure and composition are controllable compared to the vapor deposition parylene method. Strong, the monomer is highly selective.

2. The substrate moves in the reaction chamber, so that the coating thickness of the substrate at different positions tends to be uniform, which solves the problem that the thickness of the coating on the surface of the substrate is not uniform due to the difference in monomer density in different regions of the reaction chamber. During the preparation process, the combination of the motion characteristics of the substrate and the plasma discharge energy, while the discharge energy is output, the substrate moves, and the deposition efficiency is improved, so that the denseness of the obtained silicone nano protective coating is remarkably improved. At the same time, due to the increase of deposition efficiency, the amount of chemical monomer raw materials used in monomer steam is only 10% to 15% of the amount in other prior art, thereby reducing emissions of exhaust gas, making it more environmentally friendly and improving actual production efficiency. It has great significance.

3. General plasma polymerization uses a monofunctional hydrocarbon-hydrogen organic compound monomer to obtain a coating having a certain cross-linking structure. The crosslinked structure is formed by a plurality of active sites formed by chain scission of a monomer during plasma discharge by cross-linking. However, this crosslinked structure is relatively loose, contains more linear components, and is resistant to solution penetration and solubility.

Compared with the conventional monofunctional organic monomer, under the plasma condition, the silicon-bonded functional groups in the silicone monomer can undergo a condensation reaction with each other, and therefore, a three-dimensional network can occur between the monomer and the monomer. Cross-linking can further improve the compactness, wear resistance and corrosion resistance of the coating.

(1) Replacing a conventional monofunctional hydrocarbon-hydrogen organic compound monomer with a silicone monomer containing a double bond, Si-Cl, Si-OC, Si-N-Si, Si-O-Si structure or a cyclic structure Under the plasma condition, since the functional groups linked to silicon have high reactivity, these organosilicon monomers have more crosslinkable active sites;

(2) An additional crosslinking point is introduced by introducing other monomer components having a polyfunctional crosslinked structure to form a crosslinked structure. During plasma discharge, under the action of low temperature plasma, the active group with higher energy in the monomer component is broken to form an active point by effective control and output of energy, and the additional active point introduced is in the plasma environment. They cross-link and polymerize to form a dense network structure.

Compared with the loose coating composition with more linear components, the mesh structure has better compactness and can effectively improve the anti-wear and anti-corrosion properties of the film. In the plasma environment, the surface of the coated substrate is activated to obtain a plurality of active sites. The active sites are combined with the active radicals of the plasma-excited monomeric material with strong chemical bonds, and various forms of primitives are generated. The reaction makes the nano film of the base material have excellent bonding force and mechanical strength. By controlling the mixing mode of different monomers and controlling different process conditions at the same time, the effective control of the corrosion-resistant environment of the material surface is realized, and the structure with large roughness of the underlying dense surface layer with special microstructure is obtained, and the comprehensive performance of environmental corrosion resistance is obtained. Increased by 20% to 35%, hardness can reach 2H-4H.

4. The invention utilizes plasma chemical vapor deposition to obtain a protective coating with excellent performance by controlling the structure of the monomer and the coating. The coating has the following advantages: the thickness is controllable between 20 nm and 10 μm; It is controllable between 2H-4H; it has excellent insulation performance and underwater power resistance; it has excellent three-proof performance.

5. Since the group linked to silicon in the organosilicon monomer has high activity, it is easier to generate free radicals and crosslink reaction in the case of low temperature plasma to form a dense cross-linking compound; oxygen can be introduced into the coating. Produces a high-hardness nano-silica phase, which effectively improves the hardness of the coating. After hardening, the silicone-based coating can achieve a hardness of 2H-4H, which can effectively improve the wear resistance and prolong the service life of the coating. .

By introducing other monomers of the crosslinked structure, controlling the monomer ratio, according to the difference of molecular bond energy, bond length difference and vaporization temperature of different monomers, the corresponding energy output and effective changes of process parameters are given to the device, and the composite is obtained. The gradual structure of the polymer nano-coating not only ensures the hydrophobicity of the film, but also improves the corrosion resistance and wear resistance of products such as electronic products. When the mass percentage of silica in the coating is 20%, the ratio is The abrasion resistance of the silica-free coating is increased by 2-3 times.

Electronic equipment in daily life is extremely vulnerable to corrosion by corrosive environments, and is basically in a corrosive environment during use. In the long run, it will cause irreparable damage to electronic equipment. The typical plasma organic coating has a hardness of HB-2H, has poor wear resistance, and has a relatively short service life. The coating method of the patent of the invention greatly increases the significance of the nanometer in improving the actual production efficiency. The hardness of the coating is increased by more than 2 times, and the service life of the corrosive and easy-to-contact environment is increased by 4-6 times, which effectively improves the protection effect of the product. Mainly used in the following products:

(1), portable device keyboard: portable keyboard has small and light features, commonly used in computers, mobile phones and other equipment. It makes it easy for users to work on the journey. However, when it encounters the contamination of common liquids, such as the accidental overturn of the water cup, the soaking of rain and sweat, the inside of the keyboard is easily short-circuited and damaged. After coating with this type of nano-coating, it can ensure that the surface of the keyboard is easy to clean and function properly after being exposed to water, so that the keyboard can adapt to a more severe environment.

(2), LED display: LED display has product promotion, store decoration, lighting, warning and other purposes. Some of its uses need to face the harsh environment of rain or dust, such as the rainy days, the mall's open-air LED advertising screen, road warning lights, LED display control panel in the production workshop, these harsh environments lead to LED screen failure, and easy to accumulate dust, It is difficult to clean, and after using the nano-coating, the above problems can be effectively solved.

(3), intelligent fingerprint lock: fingerprint lock is a smart lock, which integrates computer information technology, electronic technology, mechanical technology and modern hardware technology, is widely used in public security criminal investigation and judicial field. However, after it meets water, its internal circuit is short-circuited, difficult to repair, and requires violent de-locking. This coating can be used to avoid this problem.

(4), hearing aid, Bluetooth headset: There is no communication line between the hearing aid and the Bluetooth headset. After using this coating, the user can use it in a water environment for a certain period of time, such as bathing, raining, the equipment will not be infiltrated by rain. damage.

(5) Some sensors: Some sensors need to work in a liquid environment, such as water pressure, oil pressure sensors, and sensors used in underwater operation equipment, as well as sensors that often encounter water in the working environment. These sensors use this coating. After the layer, it can guarantee that the sensor will not malfunction due to the liquid invading the internal structure of the mechanical device.

(6) Most 3C products: such as mobile phones, notebooks, PSPs, etc.

(7) Other equipment that needs to be waterproof: including equipment that needs to work in a humid environment, or may encounter unexpected accidents such as liquid spills, which may affect the normal operation of internal weak current lines.

The silicone nano-coating prepared by the method can also be applied to the following different environments and related products:

Waterproof, moisture proof, moldproof:

1 House interior: bathroom top, wallpaper, chandeliers, curtains, screens. 2 daily necessities: mosquito nets, table lamp covers, chopsticks, car rearview mirrors. 3 Cultural relics and works of art: copybooks, antiques, woodcarving, leather, bronze, silk, costumes, ancient books. 4 Electronic components and electronic products: sensors (working in wet or dusty environments), chips of various electronic products (electronic sphygmomanometers, smart watches), circuit boards, mobile phones, LED screens, hearing aids. 5 precision instruments and optical equipment: mechanical watches, microscopes.

Acid and alkaline solvents, acid and alkali salt spray, acid resistant atmosphere:

1 housing interior parts: wallpaper, tiles. 2 protective equipment: acid (alkali) gloves, acid (alkali) protective clothing. 3 Mechanical equipment and pipelines: flue desulfurization equipment, seals (acid/alkaline lubricants), pipes, valves, large-diameter sea pipelines, etc. 4 various reactors, reactors. 5 chemical production, storage; sewage treatment, aeration tank; 6 other: acid and alkali workshop, anti-alkali aerospace, energy and power, steel and metallurgy, petrochemical, medical and other industries, storage containers, statues (reduced acid rain Corrosion), sensor (acid/alkaline environment).

Soaked with organic solvents, resistant to cosmetics, sweat resistant:

1 such as paraffin, olefin, alcohol, aldehyde, amine, ester, ether, ketone, aromatic hydrocarbon, hydrogenated hydrocarbon, terpene olefin, halogenated hydrocarbon, heterocyclic compound, nitrogen-containing compound and sulfur compound solvent; 2 cosmetic packaging container ; 3 fingerprint lock, headphones.

Resistance to cold and heat cycle (-40 ° C ~ +75 ° C), resistance to heat and humidity (humidity 75% ~ 95%): electrical, electronic, automotive electrical, such as aviation, automotive, home appliances, scientific research and other fields of equipment.

Detailed ways

The invention will be described in detail below with reference to specific embodiments, but the invention is not limited to the specific embodiments.

Example 1

A method for preparing a silicone hard nano protective coating comprises the following steps:

(1) Pre-processing:

The substrate is placed in a reaction chamber of the nano-coating preparation device, the reaction chamber is closed, and the reaction chamber is continuously evacuated, and the vacuum in the reaction chamber is pumped to 10 mTorr, and an inert gas Ar is introduced to open the moving mechanism. , causing the substrate to generate motion in the reaction chamber;

The substrate in the step (1) is a solid material, and the solid material is a block-shaped polytetrafluoroethylene sheet.

In the step (1), the reaction chamber is a rotating body chamber, the volume of the reaction chamber is 50 L, the temperature of the reaction chamber is controlled at 30 ° C, and the flow rate of the inert gas is 5 sccm.

In the step (1), the substrate moves in the reaction chamber, and the substrate moves in the form of a circular motion of the substrate relative to the reaction chamber at a rotation speed of 3 rpm.

(2) Preparation of silicone coating:

Passing monomer vapor into the reaction chamber to a vacuum of 30 mTorr, plasma discharge is started, chemical vapor deposition is performed, and a silicone nano-coating is prepared by chemical vapor deposition on the surface of the substrate;

The monomer vapor component is:

a mixture of a silicone monomer having a double bond structure and three polyfunctional unsaturated hydrocarbons and a hydrocarbon derivative, the mass fraction of polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives in the monomer vapor 15%;

In the step (2): plasma discharge, chemical vapor deposition, the plasma discharge process is a low-power continuous discharge during the deposition process, specifically including the following deposition process:

The deposition process includes the pretreatment stage and the coating stage. The plasma discharge power of the pretreatment stage is 150W, the discharge time is 450s, and then enters the coating stage. The plasma discharge power is adjusted to 150W and the continuous discharge time is 600s.

In step (2):

Passing monomer steam to atomize and volatilize the monomer through the feed pump, and introduce the reaction chamber into the reaction chamber by a low pressure of 10 mTorr, and the flow rate of the monomer vapor is 1000 μL/min;

The organosilicon monomer containing a double bond structure is: 3-butenyltrimethylsilane;

The three polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives are: 1,4-pentadiene, ethoxylated trimethylolpropane triacrylate, ethylene glycol diacrylate;

(3) Surface hard treatment:

Stopping the monomer vapor, introducing oxygen, the flow rate is 10 μL/min, plasma discharge, discharge power is 50 W, and the discharge time is 180 s, and the surface of the silicone nano-coating layer is hard-treated;

The plasma discharge mode in the step (2) and the step (3) is radio frequency discharge.

(4) Post-processing:

Stop the oxygen supply, stop the plasma discharge, continue to vacuum, keep the vacuum of the reaction chamber at 10 mTorr, and then open the air to an atmospheric pressure after 1 min, stop the movement of the substrate, and then take out the substrate.

The resulting polytetrafluoroethylene sheet deposited with silicone coating was tested in the GJB 150.10A-2009 mold test standard with the following performance:

Example 2

(1) Pre-processing:

The substrate is placed in a reaction chamber of the nano-coating preparation device, the reaction chamber is closed, and the reaction chamber is continuously evacuated, and the vacuum in the reaction chamber is pumped to 60 mTorr, and an inert gas He is introduced to start the moving mechanism. Moving the substrate;

The substrate in the step (1) is a solid material, and the solid material is a bulk aluminum alloy material.

In the step (1), the reaction chamber is a cubic chamber, the volume of the reaction chamber is 250 L, the temperature of the reaction chamber is controlled at 43 ° C, and the flow rate of the inert gas is 18 sccm.

In the step (1), the substrate is subjected to planetary motion, the revolution speed is 2 rpm, and the rotation speed is 6 rpm.

(2) Preparation of silicone coating:

Passing monomer vapor into the reaction chamber to a vacuum of 110 mTorr, plasma discharge is started, chemical vapor deposition is performed, and a silicone nano-coating is prepared by chemical vapor deposition on the surface of the substrate;

The monomer vapor component is:

a mixture of three Si-Cl-containing organosilicon monomers and four polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives, the mass of polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives in the monomer vapor The score is 23%;

In the step (2): plasma discharge, chemical vapor deposition, the plasma discharge process is a low-power continuous discharge during the deposition process, specifically including the following deposition process three times:

The deposition process includes a pretreatment stage and a coating stage. The plasma discharge power of the pretreatment stage is 600 W, the discharge time is 60 s, and then enters the coating stage. The plasma discharge power is adjusted to 10 W and the continuous discharge time is 3600 s.

In step (2):

The monomer steam is introduced into the reaction chamber by atomizing and volatilizing the monomer, and is introduced into the reaction chamber by a low pressure of 60 mTorr, and the flow rate of the monomer vapor is 700 μL/min;

The three Si-Cl-containing silicone monomers are: methylvinyldichlorosilane, trifluoropropyltrichlorosilane, and tributylchlorosilane;

The four polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives are: 1,4-pentadiene, polyethylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol divinyl ether

(3) Surface hard treatment:

Stop the introduction of the monomer vapor, pass oxygen and water vapor, the volume percentage of oxygen is 26%, the flow rate is 30 μL/min, the plasma discharge, the discharge power is 70W, the continuous discharge time is 140s, and the nano-coating of the silicone Hard surface treatment of the layer surface;

The plasma discharge mode in the step (2) and the step (3) is an intermediate frequency discharge.

(4) Post-processing:

Stop the oxygen and water vapor, stop the plasma discharge, continue to vacuum, keep the vacuum of the reaction chamber at 100 mTorr, and then pass the air to an atmospheric pressure after 2 min, then take out the substrate.

The hardness of the above aluminum alloy coating film is 4H, and its acid and alkali resistance are tested by exposure to acid and alkali environment. The test results are as follows:

Example 3

(1) Pre-processing:

The substrate is placed in a reaction chamber of the nano-coating preparation device, the reaction chamber is closed, and the reaction chamber is continuously evacuated, and the vacuum in the reaction chamber is drawn to 130 mTorr, and a mixture of inert gases Ar and He is introduced. a gas that activates a moving mechanism to move the substrate;

The substrate in the step (1) is a solid material, and the solid material is a bulk alloy steel sheet material.

In the step (1), the reaction chamber is a rotating body chamber, the volume of the reaction chamber is 480 L, the temperature of the reaction chamber is controlled at 50 ° C, and the flow rate of the inert gas is 80 sccm.

In the step (1), the substrate was subjected to a circular motion at a rotation speed of 8 rpm.

(2) Preparation of silicone coating:

Passing monomer vapor into the reaction chamber to a vacuum of 170 mTorr, plasma discharge is started, chemical vapor deposition is performed, and a silicone nano-coating is prepared by chemical vapor deposition on the surface of the substrate;

The monomer vapor component is:

a mixture of four Si-OC structured silicone monomers and a polyfunctional unsaturated hydrocarbon and a hydrocarbon derivative, the mass fraction of polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives in the monomer vapor 37%;

Plasma discharge, chemical vapor deposition, plasma discharge process during the deposition process is pulse discharge, specifically including the following deposition process four times:

The deposition process includes pretreatment stage and coating stage. The plasma discharge power of the pretreatment stage is 150W, the discharge time is 450s, and then enters the coating stage. The coating stage is pulse discharge, power 300W, time 600s, pulse discharge frequency is 1HZ, pulse The duty cycle is 1:1.

In step (2):

The monomer steam is introduced into the reaction chamber by atomizing and volatilizing the monomer through a feed pump, and the flow rate of the monomer vapor is 580 μL/min;

The four Si-O-C structure-containing silicone monomers are: diphenyldiethoxysilane, dodecyltrimethoxysilane, triethylvinylsilane, hexaethylcyclotrisiloxane;

The polyfunctional unsaturated hydrocarbon derivative is: neopentyl glycol diacrylate;

(3) Surface hard treatment:

Stop the introduction of the monomer vapor, pass oxygen and water vapor, the volume percentage of oxygen is 37%, the flow rate is 60 μL/min, the plasma discharge, the discharge power is 60W, the continuous discharge time is 130s, and the nano-coating of the silicone Hard surface treatment of the layer surface;

The plasma discharge mode in the step (2) and the step (3) is high frequency discharge, and the waveform of the high frequency discharge is a bipolar pulse.

(4) Post processing

Stop the oxygen and water vapor, stop the plasma discharge, continue to vacuum, keep the vacuum of the reaction chamber at 160 mTorr, and then pass the air to an atmospheric pressure after 3 min, then take out the substrate.

The above alloy steel plate material is coated with a coating hardness of 4H, immersed in an organic solvent, and tested for resistance to organic solvents. The test results are as follows:

Example 4

(1) Pre-processing:

The substrate is placed in a reaction chamber of the nano-coating preparation device, the reaction chamber is closed, and the reaction chamber is continuously evacuated, and the vacuum in the reaction chamber is pumped to 160 mTorr, and an inert gas He is introduced to start the moving mechanism. Moving the substrate;

In the step (1), the substrate is a solid material, and the solid material is a bulk aluminum material and a PCB board.

The volume of the reaction chamber in the step (1) was 640 L, the temperature of the reaction chamber was controlled at 53 ° C, and the flow rate of the inert gas was 160 sccm.

In step (1), the substrate is linearly reciprocated at a speed of 32 mm/min.

(2) Preparation of silicone coating:

Passing monomer vapor into the reaction chamber to a vacuum of 210 mTorr, plasma discharge is started, chemical vapor deposition is performed, and a silicone nano-coating is prepared by chemical vapor deposition on the surface of the substrate;

The monomer vapor component is:

a mixture of three organosilicon monomers containing Si-N-Si or Si-O-Si structure and five polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives, said polyfunctional unsaturated hydrocarbons in said monomer vapor and The hydrocarbon derivative accounts for 65% by mass;

Plasma discharge, chemical vapor deposition, plasma discharge process during the deposition process is pulse discharge, specifically including the following deposition process:

The deposition process includes pretreatment stage and coating stage. The plasma discharge power of the pretreatment stage is 600W, the discharge time is 60s, and then enters the coating stage. The coating stage is pulse discharge, power 10W, time 3600s, pulse discharge frequency is 1000HZ, pulse The duty cycle is 1:500.

In step (2):

The monomer steam is introduced into the reaction chamber by atomization and volatilization, and is introduced into the reaction chamber by a low pressure of 160 mTorr, and the flow rate of the monomer vapor is 260 μL/min;

The three organosilicon monomers containing Si-N-Si or Si-O-Si structure are: hexamethylcyclotrisilylamino, hexamethyldisilazane, hexamethyldisiloxane;

The five polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives are: 1,3-butadiene, 1,6-hexanediol diacrylate, ethylene glycol diacrylate, diethylene glycol divinyl Ether, neopentyl glycol diacrylate;

(3) Surface hard treatment:

Stopping the introduction of the monomer vapor, introducing water vapor, the flow rate is 100 μL/min, plasma discharge, discharge power is 100 W, and the discharge time is 50 s, and the surface of the silicone nano-coating layer is hard-treated;

The plasma discharge mode in steps (2) and (3) is microwave discharge.

(4) Post-processing:

Stop the water vapor, stop the plasma discharge, continue to vacuum, keep the vacuum of the reaction chamber at 200 mTorr, and then pass the air to an atmospheric pressure after 4 minutes, then take out the substrate.

The silicone coating deposited on the bulk aluminum material has a hardness of 4H and a silicone coating deposited on the PCB with a hardness of 2H. The two coated materials are exposed to the cold and heat cycle test environment to test the cold and heat cycle impact resistance. The test results are as follows:

Example 5

(1) Pre-processing:

The substrate is placed in a reaction chamber of the nano-coating preparation device, the reaction chamber is closed, and the reaction chamber is continuously evacuated, and the vacuum in the reaction chamber is pumped to 200 mTorr, and an inert gas Ar is introduced to start the moving mechanism. Moving the substrate;

The substrate in the step (1) is a solid material, and the solid material is an electronic component.

The volume of the reaction chamber in the step (1) was 1000 L, the temperature of the reaction chamber was controlled at 60 ° C, and the flow rate of the inert gas was 300 sccm.

In the step (1), the substrate was subjected to a curve reciprocating motion at a speed of 120 mm/min.

(2) Preparation of silicone coating:

Passing monomer vapor into the reaction chamber to a vacuum of 300 mTorr, plasma discharge is started, chemical vapor deposition is performed, and a silicone nano-coating is prepared by chemical vapor deposition on the surface of the substrate;

The monomer vapor component is:

a mixture of four cyclic-containing organosilicon monomers and three polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives, the mass fraction of polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives in the monomer vapor 48%;

Plasma discharge, chemical vapor deposition, plasma discharge process during the cycle is alternately discharged, specifically including the following deposition process three times:

The deposition process includes the pretreatment stage and the coating stage. The plasma discharge power of the pretreatment stage is 150W, the continuous discharge time is 450s, and then enters the coating stage. The plasma in the coating stage is the periodic alternating discharge output, power 300W, time 600s, alternating frequency At 1 Hz, the plasma cycle alternately changes the discharge output waveform to a sawtooth waveform;

In step (2):

The monomer steam is introduced into the reaction chamber by atomizing and volatilizing the monomer, and is introduced into the reaction chamber by a low pressure of 200 mTorr, and the flow rate of the monomer vapor is 10 μL/min;

The four silicone monomers containing a cyclic structure are: bis(tritylsilyl) chromate, trifluoropropylmethylcyclotrisiloxane, 2,2,4,4-tetramethyl a group of 6,6,8,8-tetraphenylcyclotetrasiloxane, tetramethyltetravinylcyclotetrasiloxane;

The three polyfunctional unsaturated hydrocarbon derivatives are: 1,4-pentadiene, tripropylene glycol diacrylate, neopentyl glycol diacrylate.

(3) Surface hard treatment:

Stop the introduction of the monomer vapor, pass oxygen and water vapor, the volume percentage of oxygen is 23%, the flow rate is 80 μL/min, the plasma discharge, the discharge power is 80W, the continuous discharge time is 90s, and the nano-coating of the silicone Hard surface treatment of the layer surface;

The plasma discharge mode in the step (2) and the step (3) is a spark discharge.

(4) Post-processing:

Stop the introduction of the oxygen and water vapor while stopping the plasma discharge, fill the reaction chamber with inert gas to a pressure of 2000 mTorr, then evacuate to 10 mTorr, perform the above-mentioned aeration and vacuum steps once, and introduce air. At one atmosphere, stop the movement of the substrate and then remove the substrate. The above-mentioned coated electronic components have a coating hardness of 2H, and are exposed to the damp heat test environment to test the resistance to moisture and heat exchange. The test results are as follows:

Example 6

(1) Pre-processing:

The substrate is placed in a reaction chamber of the nano-coating preparation device, the reaction chamber is closed, and the reaction chamber is continuously evacuated, and the vacuum in the reaction chamber is pumped to 180 mTorr, and an inert gas Ar is introduced to start the moving mechanism. Moving the substrate;

Step (1) The substrate is a solid material, and the solid material is an electrical component.

The volume of the reaction chamber in the step (1) was 780 L, the temperature of the reaction chamber was controlled at 50 ° C, and the flow rate of the inert gas was 200 sccm.

In the step (1), the substrate is subjected to planetary motion, the revolution speed is 4 rpm, and the rotation speed is 3 rpm.

(2) Preparation of silicone coating:

Passing monomer vapor into the reaction chamber to a vacuum of 280 mTorr, plasma discharge is started, chemical vapor deposition is performed, and a silicone nano-coating is prepared by chemical vapor deposition on the surface of the substrate;

The monomer vapor component is:

a mixture of five cyclic-containing organosilicon monomers and five polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives, the mass of polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives in the monomer vapor The score is 45%;

Plasma discharge, chemical vapor deposition, plasma discharge process is a periodic alternating discharge during deposition, specifically including the following deposition process:

The deposition process includes the pretreatment stage and the coating stage. The plasma discharge power of the pretreatment stage is 600W, the continuous discharge time is 60s, and then enters the coating stage. The plasma in the coating stage is the cycle alternating discharge output, power 10W, time 3600s, alternating frequency For 1000 Hz, the plasma cycle alternately changes the discharge output waveform to a full-wave rectified waveform;

In step (2):

The monomer steam is introduced into the reaction chamber by atomizing and volatilizing the monomer, and is introduced into the reaction chamber by a low pressure of 180 mTorr, and the flow rate of the monomer vapor is 49 μL/min;

The five kinds of silicone monomers containing a cyclic structure: hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, octaphenylcyclotetrasiloxane, Diphenyldihydroxysilane;

The five polyfunctional unsaturated hydrocarbon derivatives are: 1,3-butadiene, isoprene, ethoxylated trimethylolpropane triacrylate, polyethylene glycol diacrylate, 1 , 6-hexanediol diacrylate;

(3) Surface hard treatment:

Stop the introduction of the monomer vapor, pass oxygen and water vapor, the volume percentage of oxygen is 58%, the flow rate is 100 μL/min, the plasma discharge, the discharge power is 70W, the continuous discharge time is 120s, and the nano-coating of the silicone Hard surface treatment of the layer surface;

In the step (2) and the step (3), the plasma discharge mode is an intermediate frequency discharge, and the waveform of the intermediate frequency discharge is sinusoidal.

(4) Post-processing:

Stop the introduction of the oxygen and water vapor while stopping the plasma discharge, charge the reaction chamber with air to a pressure of 5000 mTorr, then evacuate to 200 mTorr, perform the above aeration and vacuum steps 10 times, and introduce air. At one atmosphere, stop the movement of the substrate and then remove the substrate. After the above-mentioned coated electrical parts, the coating hardness was 4H, and the underwater electric resistance and underwater immersion test were tested in the environment described in the international industrial waterproofing standard IPX7. The test results are as follows:

The following table tests the time taken for the coating prepared in this example to reach 1 mA at different voltages:

电压Voltage	3.8V3.8V	5V5V	12.5V12.5V
时间time	>48h>48h	＞24h>24h	＞24h>24h

The IPX 7 test (underwater 1m immersion test for 30 minutes) works properly.

Claims

A method for preparing a silicone hard nano protective coating, comprising: the following steps:

(1) Pre-processing:

The substrate is placed in a reaction chamber of the nano-coating preparation device, and the reaction chamber is continuously evacuated, and the vacuum in the reaction chamber is pumped to 10 to 200 mTorr, and an inert gas of He, Ar or He and Ar is introduced. Mixing the gas, opening the moving mechanism to cause the substrate to move in the reaction chamber;

(2) Preparation of silicone coating:

Passing monomer vapor into the reaction chamber to a vacuum of 30-300 mTorr, plasma discharge is started, chemical vapor deposition is performed, and a silicone nano-coating is prepared by chemical vapor deposition on the surface of the substrate;

The monomer vapor component comprises:

At least one silicone monomer containing a double bond, a Si-Cl, a Si-OC, a Si-N-Si, a Si-O-Si structure or a cyclic structure, and at least one polyfunctional unsaturated hydrocarbon and a hydrocarbon a mixture of derivatives;

The mass fraction of polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives in the monomer vapor is 15-65%;

The flow rate of the monomer to be introduced is 10 to 1000 μL/min;

(3) Surface hard treatment:

Stop the introduction of the monomer vapor, pass oxygen and / or water vapor, the flow rate is 10 ~ 100μL / min, plasma discharge, discharge power is 50-100W, continuous discharge time is 60s-180s, for nano-coating of silicone Hard surface treatment of the layer surface;

(4) Post-processing:

Stop the introduction of the oxygen and/or water vapor, stop the plasma discharge, continue to evacuate, maintain the vacuum of the reaction chamber at 10 to 200 mTorr, and then pass the atmosphere to an atmospheric pressure after 1 to 5 minutes to stop the substrate. Exercise, then remove the substrate;

Alternatively, stopping the introduction of the oxygen and/or water vapor while stopping the plasma discharge, charging the reaction chamber with air or an inert gas to a pressure of 2000-5000 mTorr, and then evacuating to 10-200 mTorr, The aeration and evacuation steps are performed at least once, the air is introduced to an atmospheric pressure, the movement of the substrate is stopped, and then the substrate is taken out.
The method for preparing a silicone hard nano protective coating according to claim 1, wherein in the step (1), the substrate generates motion in the reaction chamber, and the substrate moves in the form of a relative reaction of the substrate. The chamber performs a linear reciprocating motion or a curvilinear motion including a circular motion, an elliptical circumferential motion, a planetary motion, a spherical motion, or other irregularly curved motion.
The method for preparing a silicone hard nano protective coating according to claim 1, wherein the substrate in the step (1) is a solid material, and the solid material is an electronic product, an electrical component, or an electronic device. Assembling semi-finished products, PCB boards, metal sheets, Teflon sheets or electronic components, and any interface of the surface of the substrate after preparation of the silicone nano-coating can be exposed to water environment, mold environment, acid, alkaline solvent Environment, acid, alkaline salt spray environment, acidic atmospheric environment, organic solvent soaking environment, cosmetic environment, sweat environment, hot and cold cycle impact environment or wet heat alternating environment.
The method for preparing a silicone hard nano protective coating according to claim 1, wherein the reaction chamber in the step (1) is a rotating body chamber or a cubic chamber having a volume of 50 ～1000 L, the temperature of the reaction chamber is controlled at 30 to 60 ° C, and the flow rate of the inert gas is 5 to 300 sccm.
The method for preparing a silicone hard nano protective coating according to claim 1, wherein in the step (2): plasma discharge, chemical vapor deposition, and the plasma discharge process during the deposition comprises Low power continuous discharge, pulse discharge or periodic alternating discharge.
The method for preparing a silicone hard nano protective coating according to claim 5, wherein the plasma discharge process is a low-power continuous discharge during the deposition process, and specifically includes the following deposition process at least once:

The deposition process includes a pretreatment stage and a coating stage. The plasma discharge power in the pretreatment stage is 150-600 W, the continuous discharge time is 60-450 s, and then enters the coating stage. The plasma discharge power is adjusted to 10 to 150 W, and the continuous discharge time is 600 to 3600 s. .
The method for preparing a silicone hard nano protective coating according to claim 5, wherein the plasma discharge process during the deposition is a pulse discharge, specifically comprising the following deposition process at least once:

The deposition process includes a pretreatment stage and a coating stage. The plasma discharge power of the pretreatment stage is 150-600 W, and the continuous discharge time is 60-450 s, and then enters the coating stage. The coating stage is pulse discharge, the power is 10 to 300 W, and the time is 600 s to 3600 s. The frequency of the pulse discharge is 1 to 1000 Hz, and the duty ratio of the pulse is 1:1 to 1:500.
The method for preparing a silicone hard nano protective coating according to claim 5, wherein the plasma discharge process during the deposition is a periodic alternating discharge, specifically comprising the following deposition process at least once:

The deposition process includes a pretreatment stage and a coating stage. The plasma discharge power in the pretreatment stage is 150-600 W, and the continuous discharge time is 60-450 s, and then enters the coating stage. The plasma in the coating stage is a periodic alternating discharge output with a power of 10 to 300 W. The time is 600s~3600s, the frequency conversion rate is 1-1000Hz, and the plasma cycle alternately changes. The discharge output waveform is a sawtooth waveform, a sinusoidal waveform, a square wave waveform, a full-wave rectified waveform or a half-wave rectified waveform.
The method for preparing a silicone hard nano protective coating according to claim 1, wherein:

The silicone monomer containing a double bond, a Si—Cl, a Si—O—C, a Si—N—Si, a Si—O—Si structure or a ring structure includes:

Silicone monomer containing double bond structure: allyl trimethoxy silane, vinyl triethoxy silane, vinyl trimethyl silane, 3-butenyl trimethyl silane, vinyl tributyl ketone fluorenyl Silane, tetramethyldivinyldisiloxane, 1,2,2-trifluorovinyltriphenylsilane;

Silicone monomer containing Si-Cl bond: triphenylchlorosilane, methylvinyldichlorosilane, trifluoropropyltrichlorosilane, trifluoropropylmethyldichlorosilane, dimethylphenylchlorosilane , tributylchlorosilane, benzyldimethylchlorosilane;

Silicone monomer containing Si-OC structure: tetramethoxysilane, trimethoxyhydrogensiloxane, n-octyltriethoxysilane, phenyltriethoxysilane, vinyltris(2-methoxy Ethyl ethoxy) silane, triethyl vinyl silane, hexaethylcyclotrisiloxane, 3-(methacryloyloxy)propyl trimethoxy silane, phenyl tris(trimethyl siloxane group Silane, diphenyldiethoxysilane, dodecyltrimethoxysilane, n-octyltriethoxysilane, dimethoxysilane, 3-chloropropyltrimethoxysilane;

Silicone monomer containing Si-N-Si or Si-O-Si structure: hexamethyldisilazide, hexamethylcyclotrisilylamino, hexamethyldisilazane, hexamethyldisiloxane;

Silicone monomer containing cyclic structure: hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, hexaphenylcyclotrisiloxane, decamethylcyclopentasiloxane, octaphenyl ring Tetrasiloxane, triphenylhydroxysilane, diphenyldihydroxysilane, bis(tritylsilyl) chromate, trifluoropropylmethylcyclotrisiloxane, 2,2,4,4 -tetramethyl-6,6,8,8-tetraphenylcyclotetrasiloxane, tetramethyltetravinylcyclotetrasiloxane, 3-glycidoxypropyltriethoxysilane, γ - glycidyloxypropyltrimethoxysilane;

The polyfunctional unsaturated hydrocarbons and hydrocarbon derivatives include:

1,3-butadiene, isoprene, 1,4-pentadiene, ethoxylated trimethylolpropane triacrylate, tripropylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, ethylene glycol diacrylate, diethylene glycol divinyl ether or neopentyl glycol diacrylate.
The method for preparing a silicone hard nano protective coating according to claim 1, wherein in the steps (2) and (3), the plasma discharge mode is radio frequency discharge, microwave discharge, and intermediate frequency discharge. , high frequency discharge, spark discharge, the waveform of the high frequency discharge and the intermediate frequency discharge is a sinusoidal or bipolar pulse.