Long-acting fluorescent silicone tri-proof paint and preparation method thereof

Abstract

The present application relates to a kind of long-acting fluorescent silicone tri-proof paint and its preparation method, the long-acting fluorescent silicone tri-proof paint is prepared by including 107 glue, 201 silicone oil, filler, crosslinking agent, coupling agent, compound and catalyst, wherein, the compound is prepared by the reaction of 5,7-dihydroxy-4-methyl coumarin and isocyanate silane.The present application is prepared by the reaction of 5,7-dihydroxy-4-methyl coumarin and isocyanate silane, the compound can make the organic silicon tri-proof paint coating have long-lasting fluorescent effect characteristics when being used to prepare tri-proof paint.

Description

Technical Field

[0001] This invention belongs to the field of conformal coating technology, and relates to organosilicon conformal coating, specifically to a long-lasting fluorescent organosilicon conformal coating and its preparation method. Background Technology

[0002] Today's society is undergoing an information revolution, represented by electronic information technology, which is driving productivity development in unprecedented ways. The development and widespread application of microelectronics technology is a hallmark of this information revolution. In recent years, printed circuit boards (PCBs), a crucial carrier material for microelectronics technology, have experienced rapid development. From small chips to large integrated circuits, PCBs play a core role, inevitably demanding higher reliability. Because PCBs constantly face complex working environments, proper surface protection is essential. Conformal coatings (or adhesives) are currently the most common materials for PCB protection. Utilizing their self-film-forming properties, they create a coating of tens of micrometers on the outer layer of the PCB, preventing potential corrosion, softening, deformation, and mold growth, thus significantly reducing the failure rate of circuit boards.

[0003] Chemically, conformal coatings can be categorized into polyacrylate, polyurethane, and silicone types. Silicone conformal coatings, being soft and elastic, offer good temperature resistance and are easy to repair, making them a high-end choice for PCB boards. Most commercially available conformal coatings are colorless and transparent, but for ease of quality assessment, they typically contain trace amounts of fluorescent powder, which fluoresces on the coating surface under ultraviolet light.

[0004] The fluorescent effect of conformal coating on PCBs weakens after a period of use, possibly because the heat generated by the PCB causes the phosphor on the surface of the conformal coating to detach from the system surface. Therefore, it is necessary to improve the durability of the fluorescent effect of conformal coatings. Summary of the Invention

[0005] Based on this, the purpose of the present invention is to provide a long-lasting fluorescent silicone conformal coating that can still effectively detect fluorescence after long-term heat resistance.

[0006] A first aspect of the present invention is to provide a compound prepared by reacting 5,7-dihydroxy-4-methylcoumarin with an isocyanate-based silane; the isocyanate-based silane has the following structural formula (I):

[0007]

[0008] R is selected from methyl or ethyl.

[0009] In some embodiments, the mass ratio of 5,7-dihydroxy-4-methylcoumarin to isocyanate-based silane is (10-20):(10-15).

[0010] In some embodiments, the reaction temperature is 80°C to 90°C.

[0011] In some embodiments, the reaction time is 40 min to 60 min.

[0012] A second aspect of the present invention is to provide a method for preparing the compound as described above, comprising the following steps: reacting 5,7-dihydroxy-4-methylcoumarin with isocyanate-based silane.

[0013] In some embodiments, the mass ratio of 5,7-dihydroxy-4-methylcoumarin to isocyanate-based silane is (10-20):(10-15).

[0014] In some embodiments, the reaction temperature is 80°C to 90°C.

[0015] In some embodiments, the reaction time is 40 min to 60 min.

[0016] In some embodiments, the solvent for the reaction is at least one of toluene, xylene, dimethylformamide, and dimethylacetamide.

[0017] A third aspect of the present invention is to provide the use of the compound described above as a fluorescent agent in the preparation of conformal coatings.

[0018] In some embodiments, the conformal coating is an organosilicon conformal coating.

[0019] A fourth aspect of the present invention is to provide an organosilicon conformal coating, prepared from raw materials comprising the following parts by weight:

[0020]

[0021] In some embodiments, the silicone conformal coating is prepared from raw materials comprising the following parts by weight:

[0022]

[0023] In some embodiments, the 107 adhesive is an α,ω-dihydroxypolydimethylsiloxane with a viscosity of 100 to 10000 mPa·s at 25±0.5°C.

[0024] In some embodiments, the 201 silicone oil is a polydimethylsiloxane with a viscosity of 100 to 1000 mPa·s at 25 ± 0.5 °C.

[0025] In some embodiments, the filler is at least one selected from fumed silica and silicone resin. Preferably, the silicone resin is methyl MQ resin.

[0026] In some embodiments, the crosslinking agent is at least one of methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane.

[0027] In some embodiments, the coupling agent is at least one of aminopropyltrimethoxysilane, aminopropyltriethoxysilane, propylene oxide propyltrimethoxysilane, and propylene oxide propyltriethoxysilane.

[0028] In some embodiments, the catalyst is at least one of dibutyltin diacetate and dibutyltin dilaurate.

[0029] A fifth aspect of the present invention is to provide a method for preparing the organosilicon conformal coating as described above, comprising the following steps:

[0030] (1) Add the 107 glue, 201 silicone oil and filler to a planetary disperser, reduce the vacuum to below -0.90MPa, and stir;

[0031] (2) Restore normal pressure, add the crosslinking agent, disperse, reduce the vacuum to below -0.90MPa, and continue dispersing at the original speed;

[0032] (3) Restore normal pressure, add the coupling agent and compound, reduce the vacuum to below -0.95 MPa, and disperse;

[0033] (4) Restore normal pressure, add the catalyst, reduce the vacuum to below -0.95MPa, stir, and the product is obtained.

[0034] In some embodiments, in step (1), the stirring is performed at a speed of 20 r / min-30 r / min for 20 min-30 min; preferably, the stirring is performed at a speed of 25 r / min-30 r / min for 25 min-30 min.

[0035] In some embodiments, in step (2), the dispersion is carried out at 20 r / min-30 r / min for 20 min-30 min; preferably, it is carried out at 25 r / min-30 r / min for 25 min-30 min.

[0036] In some embodiments, the original speed is maintained for 10-20 minutes in step (2).

[0037] In some embodiments, in step (3), the dispersion is carried out at 20 r / min-40 r / min for 20 min-30 min; preferably, it is carried out at 25 r / min-35 r / min for 25 min-30 min.

[0038] In some embodiments, in step (4), the stirring is performed at 20 r / min-30 r / min for 30 min-40 min; preferably, the stirring is performed at 25 r / min-30 r / min for 35 min-40 min.

[0039] 1. In this invention, a compound is prepared by reacting 5,7-dihydroxy-4-methylcoumarin with isocyanate-based silane. When used in the preparation of conformal coatings, this compound imparts a long-lasting fluorescent effect to the silicone conformal coating, maintaining detectable fluorescence even after heating at 100°C for 1000 hours. This silicone conformal coating has high application value and can be widely used for PCB protection.

[0040] 2. The preparation method of the organosilicon conformal coating of the present invention has good repeatability. Detailed Implementation

[0041] To facilitate understanding of the present invention, a more complete description will be provided below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0042] Unless otherwise specified, experimental methods in the following examples are generally performed under standard conditions or as recommended by the manufacturer. All commonly used chemical reagents used in the examples are commercially available products.

[0043] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used in this invention includes any and all combinations of one or more of the associated listed items.

[0044] Furthermore, as used herein, the term "or" is an inclusive "or" sign and is equivalent to the term "and / or" unless the context clearly specifies otherwise. The term "based on" is not exclusive and allows for basing on other factors not described unless the context clearly specifies otherwise. Additionally, throughout the specification, the meanings of "an," "a," and "the" include plural indicators. The meaning of "in" includes both "in" and "on."

[0045] In some embodiments of the present invention, a compound is involved, which is prepared by reacting 5,7-dihydroxy-4-methylcoumarin with an isocyanate-based silane; the isocyanate-based silane has the following structural formula (I):

[0046]

[0047] R is selected from methyl or ethyl.

[0048] This invention discovers that 5,7-dihydroxy-4-methylcoumarin can react with isocyanate-based silanes, and the resulting compound retains its fluorescent properties. When used to prepare conformal coatings, this compound can impart a long-lasting fluorescent effect to the silicone conformal coating, maintaining detectable fluorescence even after heating at 100°C for 1000 hours.

[0049] Some embodiments of the present invention relate to a method for preparing the compound as described above, comprising the following steps: reacting 5,7-dihydroxy-4-methylcoumarin with isocyanate-based silane.

[0050] The reaction principle is as follows:

[0051]

[0052] In some embodiments, the mass ratio of 5,7-dihydroxy-4-methylcoumarin to isocyanate-based silane is (10-20):(10-15).

[0053] In some preferred embodiments, the mass ratio of 5,7-dihydroxy-4-methylcoumarin to isocyanate-based silane is (13-18):(11-14).

[0054] In some embodiments, the reaction temperature is 80°C to 90°C.

[0055] In some embodiments, the reaction time is 40 min to 60 min.

[0056] In some embodiments, the solvent is at least one of toluene, xylene, dimethylformamide, and dimethylacetamide.

[0057] In some embodiments, the preparation method of the compound includes the following steps: (1) adding solvent and 5,7-dihydroxy-4-methylcoumarin sequentially to a reaction vessel, and controlling the reaction temperature to 80℃-90℃; (2) adding isocyanate-based silane dropwise to the reaction vessel for reaction; (3) removing the solvent to obtain the compound.

[0058] In some preferred embodiments, the preparation method of the compound includes the following steps: (1) adding solvent and 5,7-dihydroxy-4-methylcoumarin sequentially to a reaction vessel, and controlling the reaction temperature to 80℃-90℃; (2) controlling the addition of the isocyanate-based silane within 10min-20min, and continuing the reaction for 40min-60min; (3) removing the solvent to obtain the compound.

[0059] In some embodiments, the solvent removal method is as follows: the temperature inside the reaction vessel is raised to 60°C-100°C and the vacuum is reduced to below -0.9MPa, and the solvent is removed for 100-150 minutes.

[0060] Some embodiments of the present invention relate to an organosilicon conformal coating, prepared from raw materials comprising the following parts by weight:

[0061]

[0062]

[0063] In some preferred embodiments, the 107 adhesive is an α,ω-dihydroxypolydimethylsiloxane with a viscosity of 100–10000 mPa·s at 25±0.5℃; the 201 silicone oil is a polydimethylsiloxane with a viscosity of 100–1000 mPa·s at 25±0.5℃; the filler is at least one of fumed silica and silicone resin; the crosslinking agent is at least one of methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane; the coupling agent is at least one of aminopropyltrimethoxysilane, aminopropyltriethoxysilane, propyleneoxypropyltrimethoxysilane, and propyleneoxypropyltriethoxysilane; and the catalyst is at least one of dibutyltin diacetate and dibutyltin dilaurate.

[0064] Some embodiments of the present invention relate to a method for preparing the organosilicon conformal coating as described above, comprising the following steps:

[0065] (1) Add the 107 glue, 201 silicone oil and filler to a planetary disperser, reduce the vacuum to below -0.90MPa, and stir;

[0066] (2) Restore normal pressure, add the crosslinking agent, disperse, reduce the vacuum to below -0.90MPa, and continue dispersing at the original speed;

[0067] (3) Restore normal pressure, add the coupling agent and compound, reduce the vacuum to below -0.95 MPa, and disperse;

[0068] (4) Restore normal pressure, add the catalyst, reduce the vacuum to below -0.95 MPa, and stir to obtain the product. In some preferred embodiments, the preparation method of the organosilicon conformal coating includes the following steps:

[0069] (1) Add the 107 glue, 201 silicone oil and filler to a planetary disperser, reduce the vacuum to below -0.90MPa, and stir at a speed of 20r / min-30r / min for 20min-30min;

[0070] (2) Restore normal pressure, add the crosslinking agent, disperse at 20 r / min-30 r / min for 20 min-30 min, reduce the vacuum to below -0.90 MPa, and disperse at the original speed for 10 min-20 min;

[0071] (3) Restore normal pressure, add the coupling agent and compound, reduce the vacuum to below -0.95MPa, and disperse at 20r / min-40r / min for 20min-30min;

[0072] (4) Restore normal pressure, add the catalyst, reduce the vacuum to below -0.95MPa, stir at 20r / min-30r / min for 30min-40min to obtain the product.

[0073] The present invention will be further described in detail below with reference to specific embodiments.

[0074] In the following examples, the compounds described in this invention are named as self-made fluorescent agents.

[0075] Example 1

[0076] A novel long-lasting fluorescent silicone conformal coating is prepared by the following method:

[0077] 100 parts by weight of toluene and 13 parts by weight of 5,7-dihydroxy-4-methylcoumarin were added sequentially to a reaction vessel. The reaction temperature was controlled at 80°C, and 15 parts by weight of propyltrimethoxysilane was added dropwise over 17 minutes. The reaction was continued for 40 minutes. Finally, the temperature inside the vessel was raised to 80°C and the vacuum was lowered to below -0.9 MPa for 100 minutes to remove the solvent, yielding the self-made fluorescent agent.

[0078] In a planetary disperser, add 75 parts by weight of 107 glue (viscosity 100 mPa·s at 25 ± 0.5 °C), 50 parts by weight of 201 silicone oil (viscosity 350 mPa·s at 25 ± 0.5 °C), and 5 parts by weight of silicone resin (methyl MQ resin). Reduce the vacuum to below -0.90 MPa and stir at 20 r / min for 30 min to remove air bubbles. Return to normal pressure and add 3 parts by weight of methyltrimethoxysilane. Adjust the stirring speed to 20 r / min and disperse for 20 min. Then reduce the vacuum to below -0.90 MPa again and maintain the original stirring speed for 20 min. Return to normal pressure and add 1.5 parts by weight of aminopropyltrimethoxysilane and 0.8 parts by weight of a self-made fluorescent agent. Reduce the vacuum to below -0.95 MPa and adjust the stirring speed to 20 r / min and disperse for 30 min. After restoring to normal pressure, add 1 part by weight of dibutyltin diacetate, reduce the vacuum to below -0.95MPa, adjust the stirring speed to 30r / min and stir for 35min to obtain the finished conformal coating.

[0079] Example 2

[0080] A novel long-lasting fluorescent silicone conformal coating is prepared by the following method:

[0081] 100 parts by weight of xylene and 15 parts by weight of 5,7-di-hydroxy-4-methylcoumarin were added sequentially to a reaction vessel. The reaction temperature was controlled at 90°C, and 13 parts by weight of isocyanate propyltriethoxysilane were added dropwise over 15 minutes. The reaction was continued for 60 minutes. Finally, the temperature inside the vessel was raised to 70°C and the vacuum was lowered to below -0.9 MPa to remove the solvent for 150 minutes, yielding the self-made fluorescent agent.

[0082] In a planetary disperser, add 70 parts by weight of 107 glue with a viscosity of 10000 mPa·s at 25 ± 0.5℃, 50 parts by weight of 201 silicone oil with a viscosity of 100 mPa·s at 25 ± 0.5℃, and 10 parts by weight of silica grease. Reduce the vacuum to below -0.90 MPa and stir at 30 r / min for 20 min to remove air bubbles. Return to normal pressure and add 4 parts by weight of methyltriethoxysilane. Adjust the stirring speed to 25 r / min and disperse for 25 min. Then reduce the vacuum to below -0.90 MPa and maintain the original stirring speed for 10 min. Return to normal pressure and add 1 part by weight of aminopropyltriethoxysilane and 0.7 parts by weight of a self-made fluorescent agent. Reduce the vacuum to below -0.95 MPa and adjust the stirring speed to 40 r / min and disperse for 20 min. After restoring to normal pressure, add 0.6 parts by weight of dibutyltin dilaurate, reduce the vacuum to below -0.95MPa, adjust the stirring speed to 25r / min and stir for 35min to obtain the finished conformal coating.

[0083] Example 3

[0084] A novel long-lasting fluorescent silicone conformal coating is prepared by the following method:

[0085] 100 parts by weight of dimethylformamide and 20 parts by weight of 5,7-dihydroxy-4-methylcoumarin were added sequentially to a reaction vessel. The reaction temperature was controlled at 85°C, and 12 parts by weight of isocyanate propyltriethoxysilane were added dropwise over 20 minutes. The reaction was continued for 50 minutes. Finally, the temperature inside the vessel was raised to 100°C and the vacuum was lowered to below -0.9 MPa for 125 minutes to remove the solvent, yielding the self-made fluorescent agent.

[0086] Add 80 parts by weight of 107 glue with a viscosity of 1500 mPa·s at 25 ± 0.5℃ to a planetary disperser; add 7 parts by weight of silicone resin (methyl MQ resin) and reduce the vacuum to below -0.90 MPa, stirring at 25 r / min for 25 min to remove air bubbles. Return to normal pressure, add 5 parts by weight of vinyltrimethoxysilane, adjust the stirring speed to 30 r / min and disperse for 20 min, then reduce the vacuum to below -0.90 MPa again, maintaining the original stirring speed and dispersing for 15 min. Return to normal pressure, add 2 parts by weight of glycidoxypropyltrimethoxysilane and 0.5 parts by weight of a self-made fluorescent agent, reduce the vacuum to below -0.95 MPa, and adjust the stirring speed to 30 r / min and disperse for 25 min. After restoring to normal pressure, add 0.75 parts by weight of dibutyltin diacetate and 0.1 parts by weight of dibutyltin dilaurate, reduce the vacuum to below -0.95 MPa, adjust the stirring speed to 20 r / min and stir for 40 min to obtain the finished conformal coating.

[0087] Example 4

[0088] A novel long-lasting fluorescent silicone conformal coating is prepared by the following method:

[0089] 100 parts by weight of dimethylacetamide and 10 parts by weight of 5,7-dihydroxy-4-methylcoumarin were added sequentially to a reaction vessel. The reaction temperature was controlled at 88°C, and 10 parts by weight of isocyanate propyltrimethoxysilane were added dropwise over 10 minutes. The reaction was continued for 45 minutes. Finally, the temperature inside the vessel was raised to 60°C and the vacuum was lowered to below -0.9 MPa to remove the solvent for 130 minutes, yielding the self-made fluorescent agent.

[0090] In a planetary disperser, add 60 parts by weight of 107 glue with a viscosity of 5000 mPa·s at 25 ± 0.5℃, 25 parts by weight of 201 silicone oil with a viscosity of 1000 mPa·s at 25 ± 0.5℃, and 6 parts by weight of silica. Reduce the vacuum to below -0.90 MPa and stir at 30 r / min for 30 min to remove air bubbles. Return to normal pressure and add 3 parts by weight of vinyltriethoxysilane. Adjust the stirring speed to 20 r / min and disperse for 30 min. Then reduce the vacuum to below -0.90 MPa again and maintain the original stirring speed for 17 min. Return to normal pressure and add 0.5 parts by weight of glycidoxypropyltriethoxysilane and 1.0 part by weight of a self-made fluorescent agent. Reduce the vacuum to below -0.95 MPa and adjust the stirring speed to 40 r / min and disperse for 30 min. After restoring to normal pressure, add 0.5 parts by weight of dibutyltin dilaurate, reduce the vacuum to below -0.95MPa, adjust the stirring speed to 30r / min and stir for 30min to obtain the finished conformal coating.

[0091] Example 5

[0092] A novel long-lasting fluorescent silicone conformal coating is prepared by the following method:

[0093] 100 parts by weight of toluene and 18 parts by weight of 5,7-dihydroxy-4-methylcoumarin were added sequentially to a reaction vessel. The reaction temperature was controlled at 80°C, and 11 parts by weight of propyltrimethoxysilane was added dropwise over 17 minutes. The reaction was continued for 40 minutes. Finally, the temperature inside the vessel was raised to 80°C and the vacuum was lowered to below -0.9 MPa for 100 minutes to remove the solvent, yielding the self-made fluorescent agent.

[0094] Add 65 parts by weight of 107 glue (viscosity 100 mPa·s at 25 ± 0.5℃), 5 parts by weight of 201 silicone oil (viscosity 350 mPa·s at 25 ± 0.5℃), and 8 parts by weight of silicone resin (methyl MQ resin) to a planetary disperser. Reduce the vacuum to below -0.90 MPa and stir at 20 r / min for 30 min to remove air bubbles. Return to normal pressure and add 4.5 parts by weight of methyltrimethoxysilane. Adjust the stirring speed to 20 r / min and disperse for 20 min. Then reduce the vacuum to below -0.90 MPa and maintain the original stirring speed for 20 min. Return to normal pressure and add 1.5 parts by weight of aminopropyltrimethoxysilane and 0.9 parts by weight of self-made fluorescent agent. Reduce the vacuum to below -0.95 MPa and adjust the stirring speed to 20 r / min and disperse for 30 min. After restoring to normal pressure, add 1 part by weight of dibutyltin diacetate, reduce the vacuum to below -0.95MPa, adjust the stirring speed to 30r / min and stir for 35min to obtain the finished conformal coating.

[0095] Comparative Example 1

[0096] This comparative example of silicone conformal coating includes the following steps (based on Example 1, 5,7-dihydroxy-4-methylcoumarin and isocyanate propyltrimethoxysilane are directly mixed as fluorescent agents, without prior reaction in the reaction vessel):

[0097] 13 parts by weight of 5,7-dihydroxy-4-methylcoumarin and 15 parts by weight of isocyanate propyltrimethoxysilane were mixed evenly to obtain a self-made fluorescent agent.

[0098] In a planetary disperser, add 75 parts by weight of 107 glue (viscosity 100 mPa·s at 25 ± 0.5 °C), 50 parts by weight of 201 silicone oil (viscosity 350 mPa·s at 25 ± 0.5 °C), and 5 parts by weight of silicone resin (methyl MQ resin). Reduce the vacuum to below -0.90 MPa and stir at 20 r / min for 30 min to remove air bubbles. Return to normal pressure and add 3 parts by weight of methyltrimethoxysilane. Adjust the stirring speed to 20 r / min and disperse for 20 min. Then reduce the vacuum to below -0.90 MPa again and maintain the original stirring speed for 20 min. Return to normal pressure and add 1.5 parts by weight of aminopropyltrimethoxysilane and 0.8 parts by weight of a self-made fluorescent agent. Reduce the vacuum to below -0.95 MPa and adjust the stirring speed to 20 r / min and disperse for 30 min. After restoring to normal pressure, add 1 part by weight of dibutyltin diacetate, reduce the vacuum to below -0.95MPa, adjust the stirring speed to 30r / min and stir for 35min to obtain the finished conformal coating.

[0099] Comparative Example 2

[0100] This comparative example of silicone conformal coating includes the following steps (based on Example 1, 5,7-dihydroxy-4-methylcoumarin is used directly as a fluorescent agent):

[0101] In a planetary disperser, add 75 parts by weight of 107 glue (viscosity 100 mPa·s at 25 ± 0.5 °C), 50 parts by weight of 201 silicone oil (viscosity 350 mPa·s at 25 ± 0.5 °C), and 5 parts by weight of silicone resin (methyl MQ resin). Reduce the vacuum to below -0.90 MPa and stir at 20 r / min for 30 min to remove air bubbles. Return to normal pressure and add 3 parts by weight of methyltrimethoxysilane. Adjust the stirring speed to 20 r / min and disperse for 20 min. Then reduce the vacuum to below -0.90 MPa and maintain the original stirring speed for 20 min. Return to normal pressure and add 1.5 parts by weight of aminopropyltrimethoxysilane and 0.8 parts by weight of 5,7-dihydroxy-4-methylcoumarin. Reduce the vacuum to below -0.95 MPa and adjust the stirring speed to 20 r / min and disperse for 30 min. After restoring to normal pressure, add 1 part by weight of dibutyltin diacetate, reduce the vacuum to below -0.95MPa, adjust the stirring speed to 30r / min and stir for 35min to obtain the finished conformal coating.

[0102] The fluorescent silicone conformal coatings prepared in the above examples and comparative examples were used as test objects after being cured at 23±3℃ and 50±5%RH for 14 days. In order to test the fluorescence retention ability of each group of silicone conformal coatings after long-term heat resistance, each group of coatings was heated at 100℃ for 1000h, and then directly excited with ultraviolet light and observed with the naked eye for fluorescence.

[0103] Meanwhile, the following properties of the fluorescent organosilicon conformal coatings prepared in the above embodiments and comparative examples were tested:

[0104] 1. Surface drying time: The test shall be conducted according to Method B of GB 1728-1979 for the determination of surface drying time, namely the finger touch method.

[0105] 2. Coating adhesion: Determined according to the cross-cut adhesion test method for coatings in GB / T 9286-1998.

[0106] 3. Volume resistivity: Determined according to GB / T 1410-2006 Test Method for Volume Resistivity of Solid Insulating Materials.

[0107] Enter the test results into Table 1:

[0108] Table 1

[0109]

[0110] As shown in Table 1, the coating obtained by curing the silicone conformal coating of the present invention still exhibits fluorescence after being heated at 100°C for 1000 hours and excited by ultraviolet light, demonstrating good fluorescence retention after long-term heat resistance. 5,7-Dihydroxy-4-methylcoumarin and isocyanate-based silanes can react to prepare a reactive fluorescent agent, which retains its fluorescent properties and can be chemically bonded to the silicone conformal coating, thereby greatly improving the long-term fluorescence performance of the silicone conformal coating.

[0111] Compared with Example 1, in the preparation process of the silicone conformal coating of Comparative Example 1, 5,7-dihydroxy-4-methylcoumarin and isocyanate silane did not undergo a chemical reaction first, but were added as raw materials for the preparation of the silicone conformal coating. After the silicone conformal coating was cured, the coating film obtained could not be observed to fluoresce when excited by ultraviolet light after being heated at 100°C for 1000 hours.

[0112] Compared with Example 1, in the preparation of the silicone conformal coating of Comparative Example 2, 5,7-dihydroxy-4-methylcoumarin was directly used as a fluorescent agent. After curing the silicone conformal coating, the coating film obtained could not be observed to fluoresce when excited by ultraviolet light after heating at 100°C for 1000 hours.

[0113] The above-described embodiments merely illustrate several implementation methods of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An organosilicon conformal coating, characterized in that, It is prepared from the following raw materials in parts by weight: 60-80 parts of 107 glue 201 silicone oil, 0-50 parts 5 to 10 parts of filler 3 to 5 parts crosslinking agent 0.5 to 2 parts of coupling agent, 0.5 to 1.0 parts of the compound, Catalyst: 0.5 to 1.0 parts; The structural formula of the compound is shown below: R is selected from methyl or ethyl.

2. The organosilicon conformal coating as described in claim 1, characterized in that, It is prepared from the following raw materials in parts by weight: 65-75 parts of 107 glue 5 to 45 parts of 201 silicone oil 6 to 8 parts of filler Crosslinking agent 3.5 to 4.5 parts, 1 to 1.5 parts coupling agent, 0.6 to 0.9 parts of the compound as described in claim 1, Catalyst: 0.6 to 0.9 parts.

3. The organosilicon conformal coating as described in claim 1 or 2, characterized in that, The 107 adhesive is an α,ω-dihydroxypolydimethylsiloxane with a viscosity of 100~10,000 mPa•s at 25±0.5℃; and / or, The 201 silicone oil is a polydimethylsiloxane with a viscosity of 100~1000 mPa•s at 25±0.5℃; and / or, The filler is at least one of fumed silica and silicone resin; and / or The crosslinking agent is at least one selected from methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane; and / or, The coupling agent is at least one selected from aminopropyltrimethoxysilane, aminopropyltriethoxysilane, propylene oxide propyltrimethoxysilane, and propylene oxide propyltriethoxysilane; and / or, The catalyst is at least one of dibutyltin diacetate and dibutyltin dilaurate.

4. The method for preparing the organosilicon conformal coating as described in any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Add the 107 glue, 201 silicone oil and filler to the planetary disperser, reduce the vacuum to below -0.90MPa, and stir; (2) Restore normal pressure, add the crosslinking agent, disperse, reduce the vacuum to below -0.90 MPa, and continue dispersing at the original speed; (3) Restore normal pressure, add the coupling agent and the compound, reduce the vacuum to below -0.95 MPa, and disperse; (4) Restore normal pressure, add the catalyst, reduce the vacuum to below -0.95MPa, stir, and the product is obtained.

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