A Parylene coating and its preparation method and application

Abstract

The present invention belongs to the technical field of coating materials, and specifically relates to a Parylene coating and a preparation method and application thereof, comprising a Parylene layer, a coupling agent between the Parylene layer and a substrate to be plated; the coupling agent has the following general formula: A-M-B; the mass content of N in the coupling agent is 3%-25%. The present invention can improve the adhesion or bonding force of the Parylene layer on the substrate to be plated, and greatly shorten the processing time to achieve high adhesion, while improving the wet heat aging resistance of the Parylene coating.

Description

Technical Field

[0001] The invention belongs to the technical field of coating materials, and in particular relates to a Parylene coating and a preparation method and application thereof. Background Art

[0002] Parylene layer (polyparaxylene, also known as paralon) provides various properties, such as protective properties, lubrication properties, barrier properties, insulation and withstand voltage properties. It is a new type of coating made of special materials. Parylene deposition adopts the process of vapor deposition, and Parylene itself has extremely strong water vapor barrier efficiency. Since the Parylene material itself is relatively symmetrical (weak polarity), the adhesion generated in the process of changing from gas to solid is like liquid wax turning into solid wax. It can have a little adhesion, but the adhesion strength is difficult to be used for industrialization. Therefore, the first way to interact with the substrate end is to introduce a very strong polar group, such as carboxyl, phosphate, etc., at the other end of the double bond of Parylene. The advantage of this type of group is that it is easy to greatly change the polarity of Parylene during the phase change process, thereby producing an electrostatic adsorption effect.

[0003] The second way to interact with the substrate end is that when the surface roughness of the substrate end material is large, the coupling agent with a smaller molecular weight can penetrate into the pores of the substrate, thereby forming a riveted structure (this bonding method can be understood as a physical mode in more senses). The potential condition of this bonding method is that the molecular weight must match the pores, so in the system, any substance that can control the molecular weight can change the quality of the bonding (it may develop in a good direction or in a bad direction). Therefore, generally speaking, either use coupling agents of different molecular weights to adapt to the substrate. Or use sandblasting or chemical etching processes to make the substrate suitable for the coupling agent.

[0004] The third way to interact with the substrate end is that the functional groups of the coupling agent itself can interact with the functional groups on the surface of the substrate. The most typical example is that trimethoxysilane can form a covalent bond with the hydroxyl groups on the surface of metal oxide ceramics, ultimately achieving extremely strong adhesion.

[0005] However, the coupling agent used in the prior art is a silane coupling agent, which makes the bonding force between the Parylene layer and the substrate to be plated weak, and is easy to fall off, affecting the performance of the Parylene performance of the substrate to be plated.

[0006] Moreover, the conventional silane coupling agent used in this industry is mainly soaking and evaporation. After soaking and evaporation, the adhesive force cannot be improved immediately after being taken out of the oven. It needs to go through a maturation process to ensure that the bonding force meets industrial requirements. In other words, the process of improving the adhesion of the existing silane coupling agent takes a long time.

[0007] It should be noted that this part of the present invention only provides background technology related to the present invention and does not necessarily constitute prior art or known technology. Summary of the invention

[0008] The purpose of the present invention is to overcome the defects of the prior art in that the bonding force between the Parylene layer and the substrate to be plated is weak and the process time for improving the adhesion is long, and to provide a Parylene coating and a preparation method and application thereof, wherein the Parylene coating can improve the adhesion or bonding force of the Parylene layer on the substrate to be plated, and greatly shorten the processing time for achieving high adhesion, while improving the wet heat aging resistance of the Parylene coating.

[0009] In order to achieve the above objectives, in a first aspect, the present invention provides a Parylene coating, comprising a Parylene layer, wherein a coupling agent exists between the Parylene layer and a substrate to be plated; the coupling agent has the following general formula: AMB; and the mass content of N in the coupling agent is 3%-25%.

[0010] In some preferred embodiments of the present invention, A is selected from H2C=C(R1)-COO- or H2C=CH-R2-, R1 is selected from H or an alkyl group having 1 to 3 carbon atoms, and R2 is selected from H, an alkyl group having 1 to 10 carbon atoms or a phenyl group;

[0011] B contains NH2-, NR3R4-, NHR5-, NH2-(NH) s -CO-, thiourea or , where the wavy line indicates the bond to M;

[0012] Wherein, R3 is selected from an alkyl, alkenyl or phenyl group having 1 to 9 carbon atoms, R4 is selected from an alkyl, alkenyl or phenyl group having 1 to 9 carbon atoms, and R3 and R4 cannot be phenyl groups at the same time; R5 is selected from an alkyl, alkenyl or phenyl group having 1 to 9 carbon atoms, and s is 0-2;

[0013] M contains -(CH2) n1 -、-CO-、-[O-(CH2) n2 -O] n3 -、 At least one group in

[0014] Among them, n1 is 0-12; n2 is 1-5, n3 is 1-6; a is 2-6, b is 1-3, c is 0-3, and d is 0-8.

[0015] In some preferred embodiments of the present invention, A is selected from , , or ; Wherein, the wavy line represents the connection bond with M.

[0016] In some preferred embodiments of the present invention, B comprises , , , or ; Wherein, the wavy line represents the connection bond with M.

[0017] More preferably, B comprises or , where the wavy line represents the connection bond to M.

[0018] In some preferred embodiments of the present invention, the coupling agent is allylamine, acrylamide, diallylamine, triallylamine, N-methylallylamine, N,N'-diethylacrylamide, 4-acryloylmorpholine, N,N-dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, 2-acrylic acid hydrazide or .

[0019] In some preferred embodiments of the present invention, the coupling agent accounts for 0.5%-7% of the mass of the Parylene layer, preferably 0.5%-5%, and more preferably 0.5%-3.5%.

[0020] In a second aspect, the present invention provides a method for preparing a Parylene coating, which is used for the Parylene coating described in the first aspect, and the method for preparing the Parylene coating comprises: immersing a substrate to be plated in an organic solution containing a coupling agent, and then drying; and then depositing a Parylene layer.

[0021] In some preferred embodiments of the present invention, the organic solution containing the coupling agent is obtained by dissolving the coupling agent in an organic solvent, and the mass concentration of the coupling agent in the organic solution containing the coupling agent is 0.5wt%-5wt%.

[0022] In the second aspect, in some preferred embodiments of the present invention, the immersion time is 1-2 hours, the drying conditions include: the drying temperature is 40-80°C, the time is 1-3 hours, and the conditions for depositing the Parylene layer include: the evaporation temperature is 20-30°C, and the evaporation time is 10-30 hours.

[0023] In a third aspect, the present invention provides a method for preparing a Parylene coating, which is used for the Parylene coating described in the first aspect, and the method for preparing the Parylene coating comprises: volatilizing a coupling agent under a vacuum environment; and then depositing a Parylene layer.

[0024] In some preferred embodiments of the present invention, the volatilization conditions of the coupling agent include: vacuum degree of 5-150 Pa, and time of 1.5-5 h.

[0025] In a fourth aspect, the present invention provides a method for preparing a Parylene coating, which is used for the Parylene coating described in the first aspect, and the method for preparing the Parylene coating comprises: placing a coupling agent in an atomization chamber, atomizing the coupling agent in a vacuum heating environment; and then depositing a Parylene layer.

[0026] In some preferred embodiments of the present invention, the vacuum heating conditions include: a vacuum degree of 13-33 Pa and a heating temperature of 60-200°C.

[0027] In a fifth aspect, the present invention provides use of the Parylene coating described in the first aspect in protecting the surface of a substrate to be plated.

[0028] In some preferred embodiments of the present invention, the substrate to be plated is metal, glass or ceramic.

[0029] Beneficial effects:

[0030] Through research, it was found that aminosilane, such as aminopropyltriethoxysilane, has amino and triethoxysilane as functional groups at both ends of its activity, and using this coupling agent alone cannot work in the Parylene system (it is speculated that it cannot react with Parylene to form a chemical bond), because Parylene is a free radical polymerization. In this regard, further research was conducted and the present invention was proposed.

[0031] The present invention, through the above technical scheme, especially the use of a coupling agent with a specific structure containing a carbon-carbon double bond end cap A and an N group end cap B, can improve the adhesion or bonding force of the Parylene layer on the substrate to be plated, and greatly shorten the processing time to achieve high adhesion, thereby achieving a stable adhesion of the Parylene layer on the substrate to be plated in a short process time, giving the substrate to be plated various properties of the Parylene layer (such as protective performance, lubrication performance, barrier performance, insulation and withstand voltage performance); while taking into account the improvement of the wet heat aging resistance of the Parylene coating. It is speculated that the reason may be that the coupling agent with the above specific structure has a catalytic effect and its own coupling effect, the carbon-carbon double bond and the Parylene layer can undergo a free radical polymerization reaction to chemically bond, and the coupling agent is mainly chemically bonded to the substrate to be plated by using the coordination ability of N, forming a final product of a two-layer three-dimensional coating structure (one end is the substrate, and the other end of the coupling agent is connected to Parylene).

[0032] The present invention also controls the coupling agent with an appropriate N mass content, can control the N-containing group to be within an appropriate molecular weight range and an appropriately high reactivity, matches Parylene, is beneficial to improving the adhesion or bonding force of the Parylene layer on the substrate to be plated, and greatly shortens the processing time to achieve high adhesion.

[0033] Moreover, the coupling agent of the prior art generally cannot improve the adhesion immediately after being attached and taken out of the oven, and needs to go through a maturation process to ensure that the bonding force meets industrial requirements. However, the specific coupling agent of the present invention can achieve the maximum adhesion state after the attachment coupling agent is taken out of the oven, which is mainly due to the fact that N can undergo Michael addition reaction with double bonds and potential free radical chain transfer reaction. The superposition of multiple possible reactions accelerates the overall reaction rate and shortens the processing time for improving adhesion. DETAILED DESCRIPTION

[0034] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article. Among them, the terms "optional" and "optional" all mean that they may be included or not included (or may be present or not).

[0035] In a first aspect, the present invention provides a Parylene coating, comprising a Parylene layer, wherein a coupling agent exists between the Parylene layer and a substrate to be plated; the coupling agent has the following general formula: AMB; and the mass content of N in the coupling agent is 3%-25%.

[0036] The N mass content in the coupling agent is 3%-25%, for example, it can be 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, etc., preferably 4%-11.8% or 14.5%-21.0%.

[0037] In some embodiments of the present invention, A is selected from H2C=C(R1)-COO- or H2C=CH-R2-, wherein R1 is selected from H or an alkyl group with 1-3 carbon atoms, and R2 is selected from H, an alkyl group with 1-10 carbon atoms, or a phenyl group. In A, the double bonds in acrylates and the double bonds in allyl and vinyl groups can react with Parylene, and the reaction mechanism is a free radical reaction. The above-mentioned range of A of acrylates has a faster reaction speed and a higher overall efficiency, which is more conducive to improving the adhesion or bonding force of the Parylene layer on the substrate to be plated. The above-mentioned range of A of alkenyl groups (such as allyl groups or vinyl groups, etc.) has a higher temperature resistance, which is more conducive to improving the wet heat aging resistance of the Parylene coating.

[0038] Preferably, R1 is a methyl group, and R2 is a methyl group or a phenyl group, which makes the coupling agent more active, is more conducive to improving the adhesion or bonding strength of the Parylene layer on the substrate to be plated, and further shortens the processing time to achieve high adhesion.

[0039] In some preferred embodiments of the present invention, A is selected from , , or The use of these groups A is more conducive to improving the adhesion or bonding strength of the Parylene layer on the substrate to be plated, and further shortening the processing time to achieve high adhesion.

[0040] In some preferred embodiments of the present invention, B comprises NH2-, NR3R4-, NHR5-, NH2-(NH) s -CO-, thiourea or , wherein the wavy line represents the connection bond with M; wherein R3 is selected from an alkyl, alkenyl or phenyl group with a carbon number of 1-9, R4 is selected from an alkyl, alkenyl or phenyl group with a carbon number of 1-9, and R3 and R4 cannot be phenyl groups at the same time; R5 is selected from an alkyl, alkenyl or phenyl group with a carbon number of 1-9; s is 0-2. B with the above-mentioned specific structure can coordinate with the metal substrate, or corrode the substrate, or when used in conjunction with other existing coupling agents, control the reaction activity so that the reaction speed is slower than the penetration rate, which is conducive to bonding to the surface of the substrate material with lower roughness. In addition to these groups, B can also include other groups as long as they are conducive to improving the bonding strength.

[0041] Among them, R3, R4, and R5 are preferably alkyl groups, and the alkyl group can be, for example, methyl, ethyl, propyl or an alkyl chain with a longer target number of carbon atoms and a combination thereof. Preferably, the shorter the chain length, the better, the higher the reaction activity, and the more conducive to improving the adhesion or bonding strength of the Parylene layer on the substrate to be plated.

[0042] It is understandable that B contains It means that the N of the group is connected to any of A and M.

[0043] In some more preferred embodiments of the present invention, B comprises , , , or ; Wherein, the wavy line represents the connection bond with M. The use of these groups B is more conducive to improving the adhesion or bonding force of the Parylene layer on the substrate to be plated, and further shortening the processing time to achieve high adhesion.

[0044] More preferably, B comprises or , where the wavy line represents the connection bond with M. It uses a primary amine functional group or a hydrazine functional group containing N, which has a certain corrosiveness and can corrode certain micro-channels on the surface of the substrate to be plated (especially metal), which is more conducive to increasing the possibility of improving adhesion.

[0045] In some embodiments of the invention, M comprises -(CH2) n1 -、-CO-、-[O-(CH2) n2 -O] n3 -、 In addition to these groups, M may also include other groups as long as they are beneficial to improving the binding force.

[0046] Among them, n1 is 0-12; n2 is 1-5, n3 is 1-6; a is 2-6, b is 1-3, c is 0-3, and d is 0-8. The use of M with this suitable structure can improve adhesion and promote temperature resistance, which is conducive to the use of F-type Parylene or HT-type Parylene at high temperatures. The long-term use temperature of F-type Parylene can be 180°C. The long-term use temperature of HT-type Parylene can be 350°C. n1 is 0-12, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0047] The above-mentioned specific structure of the silicon-oxygen group is used as the bridge between the two specific end caps A and B. The silicon element is connected with three oxygen-containing silicon-oxygen groups and four oxygen-containing silicon-oxygen groups, which is more conducive to the adhesion of Parylene to the substrate to be plated and improves the heat resistance of the Parylene coating.

[0048] The coupling agent AMB of the present invention can be obtained by commercial purchase or by synthesis. The synthesis method can refer to any existing synthesis method corresponding to the target structure. As long as the coupling agent of the target chemical formula is obtained, it can be used in the present invention.

[0049] Among them, including The coupling agent can be obtained commercially or by synthesis. The synthesis method can refer to the corresponding existing synthesis method of the target structure, and can be used in the present invention.

[0050] Exemplarily, the coupling agent is (In the corresponding M group, a is 2, b is 1, c is 2, and d is 5), the corresponding raw materials include:

[0051] (A447 for short), , , , The preparation process of a corresponding specific embodiment includes: putting A447 into an organic solvent (such as isopropanol), adding tetraethyl orthosilicate, hexamethyldisiloxane, adding acid (such as acetic acid), adding water to obtain a first mixture; after mixing trimethoxy [3- (methylamino) propyl] silane and 3-aminopropyl methyl dimethoxy silane, neutralizing with acid (such as acetic acid), after neutralization, obtaining a second mixture, putting the second mixture into the reactor of the first mixture, stirring and hydrolyzing, evaporating excess organic solvent; then adding an azeotropic agent (such as toluene) to azeotropically remove excess water; obtaining a dry target N-containing coupling agent.

[0052] For example, the coupling agent is The synthesis method may include: adding hydroxyethyl acrylate into a container, then adding IPDI (isophorone diisocyanate) and DBTDL (dibutyltin dilaurate), heating at 60-80°C with stirring, cooling to room temperature, and then slowly adding ethylenediamine in an ice bath (such as 0°C). After the addition is complete, the reaction is heated to room temperature for a certain period of time (such as 1h) to obtain the target coupling agent.

[0053] For another example, the coupling agent is The synthesis method may include: adding diethylene glycol monoacrylate into a container, then adding IPDI (isophorone diisocyanate) and DBTDL (dibutyltin dilaurate), heating to 60-80°C and stirring for a certain time (such as 2-4h), then cooling to room temperature, and then slowly adding ethylenediamine in an ice bath (such as 0°C). After the addition is completed, the reaction is heated to room temperature for a certain time (such as 1h) to obtain the target coupling agent.

[0054] It is understood that when n1 is 0, the coupling agent has the following general formula: AB.

[0055] In some preferred embodiments of the present invention, the coupling agent is allylamine, acrylamide, diallylamine, triallylamine, N-methylallylamine, N,N'-diethylacrylamide, 4-acryloylmorpholine, N,N-dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, 2-acrylic acid hydrazide or The preferred coupling agent is more conducive to improving the adhesion or bonding strength of the Parylene layer on the substrate to be plated, and further shortens the processing time to achieve high adhesion.

[0056] In some specific embodiments, the coupling agent is allylamine. Allylamine has a small molecular weight, strong penetrability, and strong corrosiveness. It can corrode microchannels on the surface of the substrate to be plated (especially metal), which is convenient for riveting and is more conducive to improving the bonding strength between the coupling agent and the substrate to be plated.

[0057] In some specific embodiments, the coupling agent is 4-acryloylmorpholine, which has a relatively low reactivity. It is possible to find a balance between the penetration time and reactivity of the coupling agent, which is more conducive to improving the bonding strength to the surface of the low-roughness substrate and greatly shortening the processing time.

[0058] In some preferred embodiments of the present invention, the coupling agent is 0.5%-7%, preferably 0.5%-5%, more preferably 0.5%-3.5%, more preferably 0.5%-2%, and more preferably 0.5%-1.5% of the mass of the Parylene layer. The appropriate ratio of coupling agent to Parylene can increase the total content of Parylene in the Parylene coating, which is more conducive to improving the barrier properties of the Parylene coating, and at the same time, it is more conducive to improving the bonding force to the surface of the low-roughness substrate, while greatly shortening the processing time.

[0059] The coupling agent of the present invention is applicable to any type of Parylene layer, for example, C-type, N-type, F-type or HT-type Parylene, etc., all of which can be used in the present invention.

[0060] The coupling agent of the present invention is applicable to a wide range of preparation processes, and can be applied to any existing preparation method of Parylene coatings, for example, it can be applied to an immersion method, a volatilization method, an atomization method, and the like.

[0061] In a second aspect, the present invention provides a method for preparing a Parylene coating, which is used for the Parylene coating described in the first aspect, and the method for preparing the Parylene coating comprises: immersing the substrate to be plated in an organic solution containing a coupling agent, and then drying; and then depositing a Parylene layer. The advantage of this method is that the amount of the coupling agent is relatively uniform, and the Parylene coating product has relatively stable adhesion.

[0062] In some preferred embodiments of the present invention, the organic solution containing the coupling agent is obtained by dissolving the coupling agent in an organic solvent.

[0063] The organic solvent may be, for example, at least one of isopropanol, ethanol, toluene, acetone, and butanone.

[0064] Preferably, the mass concentration of the coupling agent in the organic solution containing the coupling agent is 0.5wt%-5wt%, preferably 1wt%-5wt%. A suitable concentration of the coupling agent is more conducive to improving the barrier properties of the Parylene coating.

[0065] Preferably, the conditions for depositing the Parylene layer include: a vapor deposition temperature of 20-30° C., and a vapor deposition time of 10-30 hours, preferably 20-30 hours. The preferred conditions for depositing the Parylene layer are more conducive to improving the bonding strength.

[0066] In the second aspect, the soaking time is shorter if the substrate has no pores, and longer if the substrate has many pores. In some preferred embodiments of the present invention, the soaking time is 1-2 hours.

[0067] Preferably, the drying conditions include: a drying temperature of 40-80° C. and a drying time of 1-3 h.

[0068] In a third aspect, the present invention provides a method for preparing a Parylene coating, which is used for the Parylene coating described in the first aspect, and the method for preparing the Parylene coating comprises: volatilizing a coupling agent in a vacuum environment; and then depositing a Parylene layer. The coupling agent of the present invention is relatively easy to volatilize, and can be applied to the volatilization method of the third aspect, and is suitable for some sensitive devices or products that cannot be subjected to any surface treatment. However, the coupling agents conventionally used in the prior art have a carboxyl or phosphate group at one end. Due to the strong intramolecular hydrogen bond, this type of coupling agent is extremely difficult to be vaporized.

[0069] In some preferred embodiments of the third aspect of the present invention, the conditions for volatilization of the coupling agent include: vacuum degree of 5-150 Pa, preferably 5-40 Pa, more preferably 13-33 Pa, and time of 1.5-5 h.

[0070] In the third aspect, the coupling agent is evaporated (or heated) first, and then Parylene is deposited. The time ratio of the corresponding evaporation and deposition depends on the volatility of the coupling agent. Specifically, the heating (or evaporation) time of the coupling agent can be selected according to the target time required for the deposition thickness of Parylene. Generally speaking, assuming that Parylene with a thickness of 20μm is deposited, the time for depositing Parylene is generally 10h, and the time for evaporating the coupling agent is generally 1.5-5h. Preferably, the time for heating the coupling agent is 1.5-5h.

[0071] In a fourth aspect, the present invention provides a method for preparing a Parylene coating, which is used for the Parylene coating described in the first aspect, and the method for preparing the Parylene coating comprises: placing a coupling agent in an atomization chamber, atomizing the coupling agent in a vacuum heating environment; and then depositing a Parylene layer. The coupling agent of the present invention can be atomized under relatively low temperature conditions, can be applied to the atomization method of the fourth aspect, and is applicable to some sensitive devices or products that cannot be subjected to any surface treatment. However, the coupling agents conventionally used in the prior art have a carboxyl group or a phosphate group at one end. Due to the strong intramolecular hydrogen bond, this type of coupling agent is extremely difficult to be atomized.

[0072] In the second aspect to the fourth aspect, the deposition amount ratio of Parylene to the coupling agent can be adjusted to a suitable range by controlling the feeding amount of the coupling agent and Parylene.

[0073] In some preferred embodiments of the fourth aspect of the present invention, the vacuum heating conditions include: a vacuum degree of 13-33 Pa, a heating temperature of 60-200° C., preferably 100-200° C. The vacuum heating time is generally continuous, for example, a total of about 10-24 hours before and after the deposition of Parylene, depending on the thickness of the Parylene to be deposited.

[0074] In the second to fourth aspects of the present invention, the Parylene layer is deposited by Chemical Vapor Deposition (CVD) with Parylene N, Parylene C, Parylene F or Parylene HT as raw materials, and the deposition process can be carried out with reference to the prior art. For example, the deposition of Parylene is generally divided into three temperature zones: the first temperature zone is called the evaporation zone, and the temperature is generally controlled at 150°C; the second temperature zone is called the cracking zone, and the temperature is controlled at 690°C; the third temperature zone is called the deposition zone, and the temperature is controlled at 25°C; it is the prior art and will not be repeated here.

[0075] In a fifth aspect, the present invention provides use of the Parylene coating described in the first aspect in protecting the surface of a substrate to be plated.

[0076] In some preferred embodiments of the present invention, the substrate to be plated is any one of metal, glass, and ceramic. The metal may be, for example, copper, silver, aluminum, gold-plated, stainless steel sheet, etc. The ceramic may be, for example, an oxide or a nitride.

[0077] The embodiments of the present invention are described in detail below, which are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0078] Example 1

[0079] The coupling agent is N-methylallylamine, and the mass content of N in the coupling agent is 19.68%.

[0080] The preparation method of Parylene coating is as follows:

[0081] The coupling agent was dissolved in isopropanol to prepare a 3% immersion solution. The substrate to be plated (specifically, a glass slide, a stainless steel sheet, an aluminum sheet, a gold-plated sheet, and a copper sheet to form a Parylene coating) was immersed in the immersion solution for 1 hour, and then dried at a drying temperature of 65°C and a drying time of 1 hour; the plated device was obtained, and then the plated device was placed in a furnace, and Parylene N was used as a raw material (its commercial manufacturer is Suzhou Yaco Chemical Reagent Co., Ltd.) to deposit the Parylene layer by CVD. The conditions for depositing the Parylene layer are: the evaporation temperature is 25°C and the evaporation time is 24 hours. The mass ratio of Parylene to the coupling agent is 15:1.

[0082] Example 2

[0083] The method of Example 1 is referred to, except that the preparation method is different. Specifically, under a vacuum environment, the vacuum degree is 20 Pa, and the coupling agent is naturally volatilized for 2 hours under a vacuum environment at room temperature; after the coupling agent is completely volatilized, a Parylene layer is deposited by CVD (the deposition process is the same as that of Example 1), so that the volatilized coupling agent and Parylene react simultaneously on the surface of the substrate to be plated, and a Parylene coating with good bonding strength is obtained.

[0084] Example 3

[0085] The method of Example 1 is referred to, except that the preparation method is different. Specifically, the coupling agent is placed in an atomization chamber, in a vacuum heating environment, the vacuum degree is 20 Pa, the heating temperature is 150° C., the heating time is 2 h, the coupling agent is atomized, and then the Parylene layer is deposited by CVD (the deposition process is the same as in Example 1), so that the coupling agent and Parylene react simultaneously on the surface of the substrate to be plated to obtain a Parylene coating with good bonding strength.

[0086] Example 4

[0087] The method of Example 1 was followed, except that the coupling agent was 4-acryloylmorpholine (purchased from Sinopharm Chemical Reagent Co., Ltd.), the mass content of N in the coupling agent was 9.91%, and the other conditions remained unchanged.

[0088] Example 5

[0089] The method of Example 1 was followed, except that the coupling agent was (In the corresponding M group, a is 2, b is 1, c is 2, and d is 5), the mass content of N in the coupling agent is 4.03%, and the others remain unchanged. The preparation process of the coupling agent is as follows:

[0090] 10g (Commercial manufacturer: Momentive Performance Materials Inc. (referred to as "Momentive Company", referred to as A447) was added to 226g of isopropanol, tetraethyl orthosilicate (commercial manufacturer: Sinopharm Chemical Reagent Co., Ltd.) 19.56g, hexamethyldisiloxane (commercial manufacturer: Sinopharm Chemical Reagent Co., Ltd.) 15g, 8mL of acetic acid, and 20g of water to obtain a first mixture; trimethoxy [3- (methylamino) propyl] silane (commercial manufacturer: Sinopharm Chemical Reagent Co., Ltd.) 8.9g, 3-aminopropylmethyldimethoxysilane (commercial manufacturer: Nanjing Nengde New Materials Technology Co., Ltd.) 15.1g were mixed, and then neutralized with 9mL of acetic acid to obtain a second mixture after neutralization. The second mixture was put into the reactor of the first mixture, stirred for hydrolysis reaction for 3h, and then the excess isopropanol was evaporated by rotary evaporation; then 100ml of toluene was added to azeotropically remove excess water; the dry target N-containing coupling agent was obtained.

[0091] Example 6

[0092] The method of Example 1 was followed, except that the coupling agent was N,N'-diethylacrylamide (purchased from Sinopharm Chemical Reagent Co., Ltd.), the mass content of N in the coupling agent was 11.00%, and the other conditions remained unchanged.

[0093] Example 7

[0094] The method of Example 1 was followed, except that the coupling agent was diallylamine (purchased from Sinopharm Chemical Reagent Co., Ltd.), the mass content of N in the coupling agent was 14.41%, and the other conditions remained unchanged.

[0095] Example 8

[0096] The method of Example 1 was followed, except that the coupling agent was triallylamine (purchased from Sinopharm Chemical Reagent Co., Ltd.), the mass content of N in the coupling agent was 10.20%, and the other conditions remained unchanged.

[0097] Example 9

[0098] The method of Example 1 was followed, except that the coupling agent was allyl thiourea (purchased from Sinopharm Chemical Reagent Co., Ltd.), the mass content of N in the coupling agent was 12.05%, and the other conditions remained unchanged.

[0099] Example 10

[0100] The method of Example 1 was followed, except that the coupling agent was , the mass content of N in the coupling agent is 14.06%, and the others remain unchanged. The preparation method of the coupling agent is as follows:

[0101] 10g of hydroxyethyl acrylate was added into a three-necked flask, followed by 17.1g of IPDI and 0.031g of DBTDL. After heating at 70°C and stirring for 3h, the mixture was cooled to room temperature, and then 4.6g of ethylenediamine was slowly added in an ice bath at 0°C. After the addition was completed, the mixture was heated to room temperature and reacted for 1h to obtain a coupling agent.

[0102] Among them, hydroxyethyl acrylate (Sinopharm Chemical Reagent Co., Ltd.), IPDI (isophorone diisocyanate) (Wanhua Chemical Group Co., Ltd.), DBTDL (dibutyltin dilaurate) (Sinopharm Chemical Reagent Co., Ltd.), ethylenediamine (Sinopharm Chemical Reagent Co., Ltd.)

[0103] Embodiment 11

[0104] The method of Example 1 was followed, except that the coupling agent was , the mass content of N in the coupling agent is 12.66%, and the others remain unchanged. The preparation method of the coupling agent is as follows:

[0105] 10g of diethylene glycol monoacrylate was added into a three-necked flask, followed by 13.88g of IPDI and 0.027g of DBTDL. After heating at 70°C and stirring for 3h, the mixture was cooled to room temperature, and then 3.75g of ethylenediamine was slowly added in an ice bath at 0°C. After the addition was completed, the mixture was heated to room temperature and reacted for 1h. A coupling agent was obtained.

[0106] Among them are diethylene glycol monoacrylate (Hannong Chemicals), IPDI (isophorone diisocyanate) (Wanhua Chemical Group Co., Ltd.), DBTDL (dibutyltin dilaurate) (Sinopharm Chemical Reagent Co., Ltd.), and ethylenediamine (Sinopharm Chemical Reagent Co., Ltd.).

[0107] Example 12

[0108] The method of Example 1 is referred to, except that the amount of the coupling agent is different, and the ratio of the amount of Parylene to the coupling agent layer is adjusted to 25:1.

[0109] Embodiment 13

[0110] The method of Example 1 is referred to, except that in the immersion method of Example 1, the time for depositing the Parylene layer is adjusted, specifically, the evaporation time is shortened to 15 hours by controlling the evaporation pressure.

[0111] Embodiment 14

[0112] The method of Example 1 is referred to, except that in the preparation method of Example 2, the vacuum degree for volatilization of the coupling agent is adjusted to 100 Pa.

[0113] Embodiment 15

[0114] The method of Example 1 is referred to, except that in the preparation method of Example 3, the key process parameters are adjusted: the heating temperature is 60°C.

[0115] Example 16

[0116] The method of Example 1 was followed, except that the coupling agent was N,N-dimethylaminoethyl acrylate (purchased from Sinopharm Chemical Reagent Co., Ltd.), the N content in the coupling agent was 9.78%, and the other conditions remained unchanged.

[0117] Embodiment 17

[0118] The method of Example 1 was followed, except that the coupling agent was dimethylaminoethyl methacrylate (purchased from Sinopharm Chemical Reagent Co., Ltd.), the N content in the coupling agent was 8.91%, and the other conditions remained unchanged.

[0119] Embodiment 18

[0120] The method of Example 1 was followed, except that the coupling agent was acrylamide (purchased from Sinopharm Chemical Reagent Co., Ltd.), the N content in the coupling agent was 19.69%, and the other conditions remained unchanged.

[0121] Embodiment 19

[0122] The method of Example 1 was followed, except that the coupling agent was 2-acrylic acid hydrazide (purchased from Sinopharm Chemical Reagent Co., Ltd.), the N content in the coupling agent was 16.26%, and the other conditions remained unchanged.

[0123] Comparative Example 1

[0124] The method of Example 1 is referred to, except that the coupling agent is γ-aminopropyltriethoxysilane (purchased from Sinopharm Chemical Reagent Co., Ltd.), the N mass content in the coupling agent is 6.32%, and the others remain unchanged. It does not contain a carbon-carbon double bond and cannot undergo a free radical polymerization reaction with the Parylene layer to form a chemical bond.

[0125] Comparative Example 2

[0126] The method of Example 1 was followed, except that the coupling agent was A174 ((3-Methacryloxypropyl)trimethoxysilane, purchased from Sinopharm Chemical Reagent Co., Ltd.), and the other components remained unchanged.

[0127] Comparative Example 3

[0128] The method of Example 1 was followed, except that the coupling agent was trimethoxy[3-(methylamino)propyl]silane (purchased from Sinopharm Chemical Reagent Co., Ltd.) The mass content of N in the coupling agent was 7.24%.

[0129] Comparative Example 4

[0130] The method of Example 1 was followed, except that the coupling agent was [3-(N,N-dimethylamino)propyl]trimethoxysilane (purchased from Sinopharm Chemical Reagent Co., Ltd.) The mass content of N in the coupling agent was 6.75%.

[0131] Comparative Example 5

[0132] The method of Example 1 was followed, except that the coupling agent was The N content in the coupling agent is 1.07%. The preparation method of the coupling agent is as follows:

[0133] 10g of bis(3-trimethoxysilylpropyl)amine (commercial manufacturer: Sinopharm Chemical Reagent Co., Ltd.) was added to 186g of isopropanol, and 21.37g of hexamethyldisiloxane (commercial manufacturer: Sinopharm Chemical Reagent Co., Ltd.), 8.69g of vinyltrimethoxysilane (commercial manufacturer: Sinopharm Chemical Reagent Co., Ltd.), 14.07g of dimethyldimethoxysilane (commercial manufacturer: Sinopharm Chemical Reagent Co., Ltd.), 6mL of acetic acid and 18g of water were added to obtain a first mixture; 10g of bis(3-trimethoxysilylpropyl)amine (commercial manufacturer: Sinopharm Chemical Reagent Co., Ltd.) was neutralized with 1.75mL of acetic acid to obtain a second mixture after neutralization. The second mixture was added to the reactor of the first mixture, stirred for hydrolysis reaction for 3h, and then the excess isopropanol was evaporated by rotary evaporation; then 100ml of toluene was added to azeotropically remove excess water; and the dry target N-containing coupling agent was obtained.

[0134] Comparative Example 6

[0135] The method of Example 1 was followed, except that the coupling agent was methyl methacrylate (purchased from Sinopharm Chemical Reagent Co., Ltd.).

[0136] Test Case

[0137] The Parylene coating obtained in the above embodiment and comparative example was subjected to various performance tests shown in Table 1, and the results are shown in Table 1. Among them, the binding force was tested according to the standard ASTM D3359 hundred-grid test method, and the binding force grade is shown in Table 1. The higher the grade number, the stronger the binding force; the hundred-grid test method includes: marking the coating surface according to the standard, and then adhering it with a specific tape to see whether the coating can be adhered by the tape to judge the binding force of the coating. And because the atmosphere at different heights in the CVD deposition furnace of the Parylene coating may be different, the present invention divides the furnace into 5 different heights in the corresponding CVD deposition process in each example, and places corresponding slides (i.e., glass slides, stainless steel sheets, aluminum sheets, gold-plated sheets, and copper sheets) at different heights for coating, to obtain five groups of samples, and obtain five groups of grade data according to the above standard test, and the data with higher grade occurrence times is taken as the final data measured; for example, if the five groups of grade data of the glass slide are 5B, 5B, 4B, 4B, and 5B, the data with higher occurrence times is 5B, which is the final data measured.

[0138] Among them, the storage conditions for 2 hours or 3 days out of the oven are storage at room temperature of 25°C and humidity of 50%. After the target storage time, the bonding strength is tested according to the above standards.

[0139] The bonding strength at 150℃ for 2h refers to the bonding strength measured according to the above standard after being baked for 3 days and aged in a drying oven at 150℃ for 2h.

[0140] Double 85% refers to the bonding strength measured according to the above standard after aging for 120 hours in an environment with a temperature of 85°C and a humidity of 85% for 3 days after being baked.

[0141] Table 1

[0142]

[0143] Table 1 (Continued from Table 1)

[0144]

[0145] From the above results, it can be seen that, compared with the comparative example, the embodiment of the present invention can improve the bonding strength of the Parylene layer on the substrate to be plated, and greatly shorten the processing time to achieve high adhesion, thereby achieving a stable adhesion of the Parylene layer on the substrate to be plated in a shorter process time. Among them, comparative example 2 is a coupling agent commonly used in the industry, and the trimethoxysilane at the end acting on the substrate needs to react with water to take effect. In the absence of a catalyst, the reaction time of trimethoxysilane and water is relatively slow, and the bonding strength is significantly weaker than that of the embodiment of the present invention.

[0146] Furthermore, according to Example 1 and Examples 9-19, it can be seen that the use of the preferred specific structure coupling agent or specific process of the present invention is more conducive to improving the bonding strength of the Parylene layer on the substrate to be plated.

[0147] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A Parylene coating, comprising a Parylene layer, characterized in that: There is a coupling agent between the Parylene layer and the substrate to be plated; the coupling agent includes the following general formula: AMB; the mass content of N in the coupling agent is 3%-25%; wherein, A is selected from H2C=C(R1)-COO- or H2C=CH-R2-, R1 is selected from H or an alkyl group having 1 to 3 carbon atoms, and R2 is selected from H, an alkyl group having 1 to 10 carbon atoms or a phenyl group; B contains NH2-, NR3R4-, NHR5-, NH2-(NH) s -CO-, thiourea or , where the wavy lines represent connecting bonds; Wherein, R3 is selected from an alkyl, alkenyl or phenyl group having 1 to 9 carbon atoms, R4 is selected from an alkyl, alkenyl or phenyl group having 1 to 9 carbon atoms, and R3 and R4 cannot be phenyl groups at the same time; R5 is selected from an alkyl, alkenyl or phenyl group having 1 to 9 carbon atoms, and s is 0-2; M contains -(CH2) n1 -、-CO-、-[O-(CH2) n2 -O] n3 -、 At least one group in Among them, n1 is 0-12; n2 is 1-5, n3 is 1-6; a is 2-6, b is 1-3, c is 0-3, and d is 0-8.

2. The Parylene coating according to claim 1, characterized in that: A is selected from , , or ; and / or, B contains , , , or ; The wavy lines represent connecting keys.

3. The Parylene coating according to claim 2, characterized in that: B contains or , where the wavy lines represent connecting bonds.

4. The Parylene coating according to claim 1, characterized in that: The coupling agent is allylamine, acrylamide, diallylamine, triallylamine, N-methylallylamine, N,N'-diethylacrylamide, 4-acryloylmorpholine, N,N-dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, 2-acrylic acid hydrazide or .

5. The Parylene coating according to claim 1, characterized in that: The coupling agent is 0.5%-7% of the mass of the Parylene layer.

6. Use of the Parylene coating according to any one of claims 1 to 5 in surface protection of a substrate to be plated, wherein the substrate to be plated is metal, glass or ceramic.

7. A method for preparing a Parylene coating, characterized in that: It is used to prepare the Parylene coating as described in any one of claims 1 to 5, and the preparation method of the Parylene coating comprises: immersing the substrate to be plated in an organic solution containing a coupling agent, then drying; and then depositing a Parylene layer.

8. The method for preparing the Parylene coating according to claim 7, characterized in that: The organic solution containing the coupling agent is obtained by dissolving the coupling agent in an organic solvent, and the mass concentration of the coupling agent in the organic solution containing the coupling agent is 0.5wt%-5wt%; and / or, The immersion time is 1-2 hours, the drying conditions include: the drying temperature is 40-80° C., the time is 1-3 hours, and the conditions for depositing the Parylene layer include: the evaporation temperature is 20-30° C., and the evaporation time is 10-30 hours.

9. A method for preparing a Parylene coating, characterized in that: It is used to prepare the Parylene coating as described in any one of claims 1 to 5, and the preparation method of the Parylene coating comprises: volatilizing the coupling agent in a vacuum environment; and then depositing the Parylene layer.

10. The method for preparing the Parylene coating according to claim 9, characterized in that: The volatilization conditions of the coupling agent include: vacuum degree of 5-150 Pa, and time of 1.5-5 hours.

11. A method for preparing a Parylene coating, characterized in that: It is used to prepare the Parylene coating as described in any one of claims 1 to 5, and the preparation method of the Parylene coating comprises: placing a coupling agent in an atomization chamber, atomizing the coupling agent in a vacuum heating environment; and then depositing a Parylene layer.

12. The method for preparing the Parylene coating according to claim 11, characterized in that: The vacuum heating conditions include: vacuum degree of 13-33 Pa, heating temperature of 60-200°C.

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