Resin composition, conformal coating and application thereof

Abstract

The invention discloses a resin composition, conformal coating and application thereof. The resin composition comprises the following raw materials: organic silicon resin, silicone oil, an adhesion promoter and a solvent. The organic silicon resin comprises at least one of methyl silicon resin, phenyl silicon resin, methyl vinyl silicon resin, methyl phenyl silicon resin or methyl hydrogen silicon resin; the silicone oil comprises at least one of methyl silicone oil, hydroxyl silicone oil, vinyl-terminated silicone oil, phenyl silicone oil, methyl phenyl silicone oil or hydrogen-terminated silicone oil; the mass ratio of the organic silicon resin to the silicone oil is (1.7-5): 1. Specific organic silicon resin is adopted as a film-forming framework material and combined with specific silicone oil, the specific organic silicon resin and the specific silicone oil are compounded according to a certain mass ratio, the internal stress and hardness of a film layer can be effectively improved, the compactness and the protection effect of the film layer are improved, and the resin composition which is low in internal stress, soft in film layer and high in curing speed is obtained and can be used for preparing conformal coating. And a good protection effect is achieved in electronic products such as printed circuit boards and the like.

Description

Technical Field

[0001] This invention belongs to the field of resin composition technology, and particularly relates to a resin composition, conformal coating and its application. Background Technology

[0002] Conformal coating (moisture-proof, salt spray-proof, mildew-proof) is a thin protective film applied to the surface of a printed circuit board (PCB) to protect electronic products from moisture, chemicals, dust, stress, and other damage that may occur in the working environment, thus significantly improving the reliability and lifespan of electronic products.

[0003] Currently, commonly used conformal coatings include acrylic, polyurethane, epoxy, and silicone resins. Among them, silicone resin conformal coatings are favored due to their excellent high and low temperature resistance (typically -50℃ to 200℃), good electrical insulation, chemical inertness, and elastic recovery ability.

[0004] However, existing silicone resin conformal coatings still have some shortcomings: 1) High internal stress: During the curing process, resin shrinkage generates internal stress. For PCBs with fragile components (such as large-size BGAs, chip resistors, etc.), this stress may cause cracking of component solder joints or damage to the components themselves. 2) High hardness: The cross-linking density of silicone resin after curing is too high, which is not conducive to the electrical connection between connectors on the circuit board and other connectors. Usually, these parts need to be masked before use. However, the masked connectors cannot be coated with conformal coating, thus becoming weak points in electronic devices, which are prone to short circuits, corrosion failures, and other problems. 3) Balance between curing speed and performance: Condensation reaction silicone resins have a long curing time, usually requiring several hours to achieve initial curing. Although addition reaction silicone resins can be cured quickly by heating, the platinum catalyst is easily poisoned by substances such as solder on the circuit board, resulting in poor local curing. Summary of the Invention

[0005] In order to overcome at least one of the problems existing in the prior art, one of the objectives of the present invention is to provide a resin composition that has the characteristics of low internal stress, soft film, and fast curing speed.

[0006] The second objective of this invention is to provide a coating.

[0007] The third objective of this invention is to provide a conformal coating.

[0008] The fourth objective of this invention is to provide an application of the above-mentioned resin composition, coating or conformal coating.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A first aspect of the present invention provides a resin composition comprising the following raw materials: an organosilicon resin, a silicone oil, an adhesion promoter, and a solvent; wherein the organosilicon resin comprises at least one of methyl silicone resin, phenyl silicone resin, methyl vinyl silicone resin, methyl phenyl silicone resin, or methyl hydrogen silicone resin; wherein the silicone oil comprises at least one of methyl silicone oil, hydroxyl silicone oil, terminal vinyl silicone oil, phenyl silicone oil, methyl phenyl silicone oil, or terminal hydrogen silicone oil; and wherein the mass ratio of the organosilicon resin to the silicone oil is (1.7~5):1.

[0010] This invention uses silicone resin as the film-forming framework material; silicone oil as a flexibility modifier to improve the resin's toughness and leveling properties, and participates in film formation; an adhesion promoter is used to enhance the bonding force between the film layer and the substrate, improving the protective effect; and a solvent is used to make the composition a uniform mixture without suspended phases. This invention combines specific silicone resins and silicone oils in a certain compounding ratio, which can effectively improve the internal stress and hardness of the film layer, and enhance the film layer's density and protective effect.

[0011] Preferably, the mass ratio of the organosilicon resin to the silicone oil is (2~4):1; more preferably (2.5~3.5):1.

[0012] When silicone resin is used as a film-forming skeleton material in a composition, an excessively high proportion is not conducive to improving the internal stress and hardness of the film; while an excessively low proportion results in insufficient film density and poor protective effect. By optimizing the mass ratio of silicone resin to silicone oil, internal stress and hardness can be better reduced, and the protective effect can be improved.

[0013] Preferably, the silicone resin includes at least one of methyl silicone resin, phenyl silicone resin, or methylphenyl silicone resin; more preferably, the silicone resin is selected from methyl silicone resin.

[0014] Preferably, the structure of the silicone resin includes MQ type, MT type or a combination thereof; more preferably, the structure of the silicone resin is selected from MQ type.

[0015] Preferably, the silicone resin is selected from MQ type methyl silicone resin.

[0016] Preferably, the organosilicon resin has a weight-average molecular weight of 1000~10000 g / mol; more preferably 2000~8000 g / mol; and even more preferably 4000~5000 g / mol.

[0017] Preferably, the softening point of the silicone resin is 50~150℃.

[0018] Preferably, the silicone resin is solid at 25°C.

[0019] Preferably, the silicone oil includes at least one of methyl silicone oil, phenyl silicone oil, or methylphenyl silicone oil; more preferably, the silicone oil is selected from methyl silicone oil.

[0020] Preferably, the viscosity of the silicone oil at 25°C is 1000~10000 mPa·s; more preferably 2000~9000 mPa·s; and even more preferably 4000~6000 mPa·s.

[0021] Preferably, the adhesion promoter has the following structural formula: ; Wherein, R is methyl, ethyl, or propyl; a = 2 or 3; Y is epoxy, methacryloyloxy, amino, isocyanate, or mercapto.

[0022] Preferably, R is methyl or ethyl.

[0023] Preferably, Y is an epoxy group or an amino group.

[0024] Preferably, the adhesion promoter comprises at least one of γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, 3-aminopropyltrimethoxysilane, or 3-aminopropyltriethoxysilane; more preferably, the adhesion promoter is selected from γ-glycidoxypropyltrimethoxysilane (KH560).

[0025] Preferably, the adhesion promoter accounts for 0.1-1.5% of the total mass of the silicone resin and silicone oil; more preferably, 0.3-1.2%; and even more preferably, 0.5-1%.

[0026] Using an appropriate amount of adhesion promoter can improve adhesion and ensure good performance in other aspects.

[0027] Preferably, the solvent includes hydrocarbon solvents, organosilicon solvents, or combinations thereof.

[0028] Preferably, the hydrocarbon solvent includes alkane solvents, aromatic hydrocarbon solvents, or combinations thereof; more preferably, the hydrocarbon solvent includes at least one of n-hexane, isohexane, n-heptane, isoheptane, n-octane, isooctane, n-nonane, isononane, n-decane, isodecanane, toluene, or xylene; even more preferably, the hydrocarbon solvent includes at least one of n-hexane, isohexane, n-heptane, isoheptane, isooctane, or toluene.

[0029] Preferably, the organosilicon solvent is selected from linear organosilicon solvents with a degree of polymerization ≤10; more preferably, the organosilicon solvent includes at least one of hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane or dodecylpentasiloxane; even more preferably, the organosilicon solvent includes hexamethyldisiloxane, octamethyltrisiloxane or a combination thereof.

[0030] Preferably, the solvent includes at least one selected from n-hexane, isohexane, n-heptane, isoheptane, n-octane, isooctane, n-nonane, isononane, n-decane, isodecanane, toluene, xylene, hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, or dodecylpentasiloxane; more preferably, the solvent includes at least one selected from n-hexane, isohexane, n-heptane, isoheptane, isooctane, toluene, hexamethyldisiloxane, or octamethyltrisiloxane; even more preferably, the solvent is selected from n-hexane.

[0031] In this invention, the solvent is used to simultaneously dissolve the organosilicon resin, silicone oil, and adhesion promoter in the composition, so that the composition forms a uniform mixture without suspended phase. This is the key to achieving uniform film formation. Using the above-mentioned solvent can obtain better dispersion effect and achieve more uniform film formation.

[0032] Preferably, the relative evaporation rate of the solvent is ≥1; more preferably 1.5~6.5; even more preferably 1.8~5.5.

[0033] Relative evaporation rate measures the rate at which a solvent changes from the liquid phase to the gas phase, with the evaporation rate of n-butyl acetate as 1 as the benchmark. This invention selects a solvent with a relatively fast evaporation rate. If the solvent's evaporation rate is slow, it is not conducive to achieving rapid curing, and slow evaporation can lead to uneven surface film formation or orange peel-like phenomena. Conversely, if the solvent's evaporation rate is too fast, it can also result in poor film continuity or clog automated equipment, leading to uneven coating.

[0034] Preferably, the solvent accounts for 35-80% of the total mass of the raw materials in the resin composition; more preferably, 50-78%; and even more preferably, 70-75%.

[0035] Preferably, the sum of the mass of the silicone resin, silicone oil and adhesion promoter accounts for 20-60% of the total mass of the raw materials of the resin composition; more preferably, 26-55%; and even more preferably, 38-35%.

[0036] If the mass ratio of silicone resin, silicone oil, and adhesion promoter in the raw materials is low, the film formed in one step will be thin and the protective effect will be poor; while if the mass ratio is high, it may lead to uneven film formation or an excessively thick film, resulting in unnecessary waste. By optimizing the total mass ratio of silicone resin, silicone oil, and adhesion promoter, the protective effect and film formation performance can be better balanced.

[0037] In some embodiments of the present invention, the raw materials of the resin composition further include at least one of pigments, thixotropic agents, antioxidants, or leveling agents; in some specific embodiments of the present invention, the raw materials of the resin composition further include pigments.

[0038] In some embodiments of the present invention, the pigment may be an OB fluorescent agent. The addition of the pigment enables online detection of film uniformity, thickness, and other properties.

[0039] Thixotropic agents, antioxidants, or leveling agents can be selectively added or combined according to the requirements of the application scenario. After addition, there may be incompatibility with the main components of the composition. Compatibility screening can be carried out through experiments. Alternatively, the composition can be stirred and dispersed again before application. Once it is evenly dispersed, it can be used immediately.

[0040] A second aspect of the present invention provides a coating obtained by curing the resin composition described in the first aspect of the present invention.

[0041] Preferably, the thickness of the coating is 10~100μm; more preferably 20~50μm.

[0042] Preferably, the coating is obtained by spraying and then curing the resin composition.

[0043] A third aspect of the present invention provides a conformal coating comprising the resin composition described in the first aspect of the present invention.

[0044] The fourth aspect of the present invention provides the application of a resin composition as described in the first aspect of the present invention, or a coating as described in the second aspect of the present invention, or a conformal coating as described in the third aspect of the present invention, in the protection of electronic products.

[0045] In some embodiments of the present invention, the electronic product includes a printed circuit board (PCB), a sensor, a connector, or a transformer, etc.

[0046] The beneficial effects of this invention are as follows: This invention uses a specific organosilicon resin as the film-forming skeleton material, combined with a specific silicone oil, and blends them in a certain mass ratio. This effectively improves the internal stress and hardness of the film layer, and enhances its density and protective effect, resulting in a resin composition with low internal stress, a soft film layer, and fast curing speed. The resin composition provided by this invention can be used to prepare conformal coatings, exhibiting excellent protective effects in printed circuit boards and other electronic products. Detailed Implementation

[0047] The following specific embodiments further illustrate the content of the present invention in detail. It should also be understood that the following embodiments are only for further explanation of the present invention and should not be construed as limiting the scope of protection of the present invention. Non-essential improvements and adjustments made by those skilled in the art based on the principles described herein are all within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make selections within a suitable range based on the description herein, and are not intended to be limited to the specific data in the examples below. Unless otherwise specified, the raw materials, reagents, or apparatus used in the following embodiments and comparative examples can be obtained from conventional commercial sources or by existing known methods.

[0048] Example 1 A resin composition comprising the following raw materials: organosilicon resin, silicone oil, adhesion promoter, solvent, and OB brightener; wherein the organosilicon resin is methyl MQ resin with a weight average molecular weight of 8000 g / mol, and the amount used is 170 g; the silicone oil is methyl silicone oil with a viscosity of 9000 mPa·s, and the amount used is 100 g; the mass ratio of organosilicon resin to silicone oil is 1.7:1; the adhesion promoter is KH560, and the amount used is 0.5% of the total mass of resin and silicone oil; the solvent is n-hexane, and the amount used is 810 g, used to adjust the solid content of the composition to about 25%; the amount of OB brightener is 1‰ of the solvent mass.

[0049] The preparation method of the above resin composition is as follows: S1. In a dry environment, add silicone oil, adhesion promoter, solvent, and OB whitening agent to the reaction vessel, stir at 500 rpm, and observe the mixture until it becomes a transparent and homogeneous phase. S2. While stirring, add the silicone resin, increase the speed to 1000 rpm, and stir for 1~4 hours until completely mixed.

[0050] Example 2 A resin composition comprising the following raw materials: organosilicon resin, silicone oil, adhesion promoter, solvent, and OB brightener; wherein the organosilicon resin is methyl MQ resin with a weight average molecular weight of 4500 g / mol, and the amount used is 150 g; the silicone oil is methyl silicone oil with a viscosity of 5000 mPa·s, and the amount used is 50 g; the mass ratio of organosilicon resin to silicone oil is 3:1; the adhesion promoter is KH560, and the amount used is 0.5% of the total mass of resin and silicone oil; the solvent is n-hexane, and the amount used is 600 g, used to adjust the solid content of the composition to about 25%; the amount of OB brightener is 1‰ of the solvent mass.

[0051] The preparation method is the same as in Example 1.

[0052] Example 3 A resin composition comprising the following raw materials: organosilicon resin, silicone oil, adhesion promoter, solvent, and OB brightener; wherein the organosilicon resin is methyl MQ resin with a weight average molecular weight of 2000 g / mol, and the amount used is 200 g; the silicone oil is methyl silicone oil with a viscosity of 2000 mPa·s, and the amount used is 40 g; the mass ratio of organosilicon resin to silicone oil is 5:1; the adhesion promoter is KH560, and the amount used is 0.5% of the total mass of resin and silicone oil; the solvent is n-hexane, and the amount used is 720 g, used to adjust the solid content of the composition to about 25%; the amount of OB brightener is 1‰ of the solvent mass.

[0053] The preparation method is the same as in Example 1.

[0054] Example 4 A resin composition differs from Example 2 in that the organosilicon resin is replaced with a phenyl MT resin of the same weight-average molecular weight; the silicone oil is replaced with a phenyl silicone oil of the same viscosity; and other conditions are the same as in Example 2.

[0055] Example 5 A resin composition differs from Example 2 in that the organosilicon resin is replaced with methyl MQ resin and phenyl MT resin of the same weight-average molecular weight, which are compounded at a mass ratio of 10:1; the silicone oil is replaced with methyl silicone oil and phenyl silicone oil of the same viscosity, which are compounded at a mass ratio of 3:1; and other conditions are the same as in Example 2.

[0056] Example 6 A resin composition differs from Example 5 in that the mass ratio of methyl MQ resin and phenyl MT resin is modified to 10:4; other conditions are the same as in Example 5.

[0057] Example 7 A resin composition differs from Example 5 in that the mass ratio of methyl MQ resin and phenyl MT resin is modified to 10:7; other conditions are the same as in Example 5.

[0058] Example 8 A resin composition differs from Example 5 in that the mass ratio of methyl MQ resin and phenyl MT resin is modified to 10:10; other conditions are the same as in Example 5.

[0059] Example 9 A resin composition differs from Example 2 in that fumed silica is added to methyl silicone oil at an amount of 0.5 wt% of the methyl silicone oil, and the mixture is dispersed using a high-speed disperser to obtain a homogeneous viscous slurry; other conditions are the same as in Example 2.

[0060] Example 10 A resin composition differs from Example 2 in that the amount of KH560 is increased to 1%; other conditions are the same as in Example 2.

[0061] Example 11 A resin composition differs from Example 2 in that the amount of KH560 is reduced to 0.1%; all other conditions are the same as in Example 2.

[0062] Example 12 A resin composition differs from Example 4 in that the silicone oil is replaced with methyl silicone oil; all other conditions are the same as in Example 4.

[0063] Comparative Example 1 A resin composition differs from Example 1 in that the mass ratio of organosilicon resin to silicone oil is modified to 5.5:1; other conditions are the same as in Example 1.

[0064] Comparative Example 2 A resin composition differs from Example 1 in that the mass ratio of organosilicon resin to silicone oil is modified to 1.5:1; other conditions are the same as in Example 1.

[0065] Comparative Example 3 The mainstream silicone resin conformal coating on the market has the following main formulation: 50g modified silicone resin, 50g alkoxy-terminated polydimethylsiloxane, 5g methyltrimethoxysilane, 1g KH560, 1g titanate catalyst, 300g toluene, and 1‰ of solvent mass of OB whitening agent.

[0066] Performance testing The samples prepared above were used as conformal coatings and sprayed using the following process: feed pressure 1.8 psi, atomizing air pressure 3.6 psi, height 75 mm, speed 240 mm / s, single spray coating thickness 25~30 μm, sprayed once in both horizontal and vertical directions, controlling the final film thickness to be 50~60 μm. The following performance tests were then conducted.

[0067] 1) Appearance test: Pour the conformal coating into a glass bottle and observe the appearance, color, and state of the adhesive to see if there is any layering. "OK" indicates a colorless and transparent liquid with fluorescent blue color and no layering.

[0068] 2) Viscosity test: Rotational viscometer test, test temperature 25℃, S61# rotor, 100rpm.

[0069] 3) Needle penetration test: Prepare a 1.5mm test piece of conformal coating, and use a needle with a diameter of 0.8mm to pierce the test piece vertically from top to bottom at a speed of 0.5mm / s. Record the maximum force during the piercing process.

[0070] 4) Surface drying time test: Following the above spraying process, spray the conformal coating evenly onto the PCB board with a film thickness of 50μm. Touch the surface of the coating with your finger and record the time it takes for your finger to no longer stick to the coating. This time is recorded as the surface drying time.

[0071] 5) Adhesion Test: Following the above spraying process, evenly spray the conformal coating onto the PCB board to a thickness of 50μm. After the coating film dries, use the cross-cut adhesion test to test the adhesion between the coating film and the PCB board. The lower the grade, the better the adhesion.

[0072] 6) Protective effect test: Following the above spraying process, spray the conformal coating evenly onto the copper plate to a film thickness of 50μm. After the coating film dries, drop a 5% silver nitrate solution onto the coating film, let it stand for 5 minutes, and then observe whether the copper plate is corroded. "OK" indicates that the copper plate is not corroded.

[0073] 7) Double 85 Aging Test: Following the above spraying process, evenly spray the conformal coating onto the copper plate to a thickness of 50μm. After the coating dries, place the copper plate in a double 85 aging chamber and age for 1000 hours. Then remove the plate and observe for any abnormalities such as peeling, blistering, or cracking of the coating, and whether the copper plate is corroded. "OK" indicates that there are no abnormalities such as peeling, blistering, or cracking of the coating, and that the copper plate is not corroded.

[0074] 8) High-Temperature Aging Test: Following the above spraying process, evenly spray the conformal coating onto the copper plate to a thickness of 50μm. After the coating dries, place the copper plate in a high-temperature aging chamber at 125℃ for 1000 hours. Then, remove the plate and observe for any abnormalities such as peeling, blistering, or cracking, and whether the copper plate is corroded. "OK" indicates that there are no abnormalities such as peeling, blistering, or cracking, and that the copper plate is not corroded.

[0075] 9) Thermal Shock Aging Test: Following the above spraying process, uniformly spray the conformal coating onto the copper plate to a thickness of 50 μm. After the coating dries, place the copper plate in a thermal shock test chamber. Set the cyclic conditions to -40℃ for 30 minutes, then switch to 125℃ within 5 minutes and maintain for 30 minutes. After 1000 cycles of aging, remove the plate and observe whether there are any abnormalities such as peeling, blistering, or cracking in the coating, and whether the copper plate is corroded. "OK" indicates that there are no abnormalities such as peeling, blistering, or cracking in the coating and that the copper plate is not corroded.

[0076] 10) Salt spray aging test: Following the above spraying process, evenly spray the conformal coating onto the copper plate to a thickness of 50μm. After the coating dries, place the copper plate in a 5% neutral salt spray test chamber and age for 168 hours. Then remove the plate and observe whether there are any abnormalities such as peeling, blistering, or cracking in the coating, and whether the copper plate is corroded. "OK" indicates that there are no abnormalities such as peeling, blistering, or cracking in the coating, and that the copper plate is not corroded.

[0077] The performance test results are shown in Table 1.

[0078] Table 1 Performance test results of Examples 1-12 and Comparative Examples 1-3

[0079] As shown in Table 1, the resin compositions of Examples 1-12 exhibit low viscosity, short surface drying time, low needle penetration force, soft coating, strong adhesion, and good protective effect, as well as excellent performance in double 85% aging, high-temperature aging, thermal shock aging, and salt spray aging. The samples in each example have different viscosities, allowing for the selection of appropriate sample viscosity based on different sample preparation processes. Using low-viscosity samples in the spraying process can achieve better sample preparation results.

[0080] In Comparative Examples 1 and 2, the ratio of silicone resin to silicone oil was either too high or too low, resulting in reduced coating adhesion and a significant decrease in both protective effect and aging performance. Comparative Example 3, a commercially available silicone resin conformal coating, had a long surface drying time, high needle penetration force, and high hardness, making the copper plate susceptible to corrosion and exhibiting poor protective effect.

[0081] In summary, this invention uses a specific organosilicon resin as the film-forming skeleton material, combined with a specific silicone oil, and blends them in a certain mass ratio. This effectively improves the internal stress and hardness of the film layer, and enhances its density and protective effect, resulting in a resin composition with low internal stress, a soft film layer, and fast curing speed. The resin composition provided by this invention can be used to prepare conformal coatings, exhibiting excellent protective effects in printed circuit boards and other electronic products.

Claims

1. A resin composition, characterized in that, The product comprises the following raw materials: silicone resin, silicone oil, adhesion promoter, and solvent; the silicone resin includes at least one of methyl silicone resin, phenyl silicone resin, methyl vinyl silicone resin, methyl phenyl silicone resin, or methyl hydrogen silicone resin; the silicone oil includes at least one of methyl silicone oil, hydroxyl silicone oil, terminal vinyl silicone oil, phenyl silicone oil, methyl phenyl silicone oil, or terminal hydrogen silicone oil; the mass ratio of the silicone resin to the silicone oil is (1.7~5):

1.

2. The resin composition according to claim 1, characterized in that, The structure of the organosilicon resin includes MQ type, MT type or a combination thereof; And / or, the weight-average molecular weight of the organosilicon resin is 1000~10000 g / mol.

3. The resin composition according to claim 1, characterized in that, The viscosity of the silicone oil at 25°C is 1000~10000 mPa·s.

4. The resin composition according to claim 1, characterized in that, The structural formula of the adhesion promoter is as follows: ； Wherein, R is methyl, ethyl, or propyl; a = 2 or 3; Y is epoxy, methacryloyloxy, amino, isocyanate, or mercapto. And / or, the mass of the adhesion promoter accounts for 0.1 to 1.5% of the sum of the masses of the silicone resin and the silicone oil.

5. The resin composition according to claim 1, characterized in that, The solvent includes hydrocarbon solvents, organosilicon solvents, or combinations thereof; And / or, the solvent accounts for 35-80% of the total mass of the raw materials of the resin composition.

6. The resin composition according to claim 1, characterized in that, The sum of the mass of the silicone resin, silicone oil, and adhesion promoter accounts for 20-60% of the total mass of the raw materials in the resin composition. And / or, the raw materials of the resin composition may further include at least one of pigments, thixotropic agents, antioxidants, or leveling agents.

7. A coating, characterized in that, The resin composition according to any one of claims 1 to 6 is obtained by curing.

8. The coating according to claim 7, characterized in that, The thickness of the coating is 10~100μm.

9. A three-proof paint, characterized in that, The resin composition comprising any one of claims 1 to 6.

10. The application of a resin composition as described in any one of claims 1 to 6, or the coating as described in claim 7 or 8, or the conformal coating as described in claim 9, in the protection of electronic products.

Images