Preparation method of high insulation shielding gravure ink for precision electronics

Abstract

The application relates to a preparation method of high-insulation shielding gravure ink for precision electronics, and relates to the technical field of gravure ink. Modified polyimide resin, saturated polyester resin and organic bentonite are mixed to obtain a pre-activation mixture; mixed solvent, fluorine-containing dispersant, silane coupling agent, modified nano boron nitride and nano silicon dioxide are ultrasonically mixed to obtain a nanoscale composite dispersion liquid; the nanoscale composite dispersion liquid, carbon black, micron mica powder, leveling agent and defoaming agent are added into the pre-activation mixture, high-speed shearing, grinding, aging, filtering and high-insulation shielding gravure ink is obtained; the modified nano boron nitride is prepared from nano boron nitride, 4,4'-dimercaptodiphenyl ether and allyltrimethoxysilane. The prepared gravure ink can significantly improve the insulation performance and shielding force of the ink.

Description

Technical Field

[0001] This invention relates to the field of gravure printing ink technology, and in particular to a method for preparing a high-insulation, shielding gravure printing ink for precision electronics. Background Technology

[0002] With the rapid development of 5KG communication technology, precision electronic equipment is continuously evolving towards higher frequencies, miniaturization, and higher precision. Smartphones, laptops, and high-frequency communication devices are placing increasingly stringent demands on the performance of inks used for surface printing, especially on insulation and shielding properties, which directly determine the operational stability and lifespan of precision electronic components. Gravure inks, due to their high printing precision, uniform film layer, and strong adaptability, are widely used in the surface printing of precision electronics.

[0003] Chinese Patent CN119875424A discloses a gravure ink resistant to rust-preventing lubricating oil, comprising, by weight percentage: 10-15% chlorinated rubber resin, 10-15% styrene-butadiene rubber resin, 2-3% CPP modified resin, 3-5% polyester polyol, 2-3% polytetrafluoroethylene modified polyethylene wax, 4-6% polyamide wax, 2-3% crosslinking agent, and 50-60% color paste.

[0004] Chinese Patent CN120464253A relates to the field of ink technology and discloses an environmentally friendly water-based gravure ink for automotive interior parts and its preparation method. The invention involves grafting 2-[3-(2-(methacryloyloxy)ethyl)ureoyl]ethanesulfonic acid with chitosan to obtain modified chitosan, which is then added to an aqueous acrylic resin along with pigments, dispersants, etc., to obtain an environmentally friendly water-based gravure ink for automotive interior parts.

[0005] Existing technologies have failed to achieve a synergistic improvement in insulation and shielding performance, and have neglected the requirements for compatibility with gravure printing processes and adhesion to precision electronic substrates. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a method for preparing a high-insulation, shielding gravure ink for precision electronics. The operation steps are as follows, in parts by weight: S1: Weigh 20-35 parts of modified polyimide resin PI-UV-F600 and 6-12 parts of saturated polyester resin PES-200 by weight, mix them evenly, add 2-6 parts of organic bentonite, heat to 50-65℃, premix for 30-50 minutes to obtain a pre-activated mixture. S2: Weigh 10-25 parts of mixed solvent, add 0.3-1.5 parts of fluorine-containing dispersant and 0.1-0.8 parts of silane coupling agent, stir to dissolve, add 2-8 parts of modified nano boron nitride and 1-4 parts of nano silica, first ultrasonically disperse, then high-speed shear to obtain nanoscale composite dispersion; S3: Cool the pre-activated mixture to 25-30℃, add the nano-scale composite dispersion, and then add 5-10 parts of carbon black, 2-6 parts of micron-sized mica powder, 0.1-0.5 parts of leveling agent, and 0.2-0.6 parts of defoamer in sequence. Shear at high speed at 1500-2200 rpm for 30-60 minutes to obtain the initial mixed ink system. S4: The initial mixed ink system is put into a nano-sand mill for grinding. The grinding temperature is 26-32℃ and the grinding time is 2-4h until the ink fineness is 0.03-0.05μm to obtain refined ink. S5: Transfer the refined ink into a curing kettle and cure it for 1-3 hours at a low speed of 25-30℃ and 500-800rpm. Check the viscosity every 30 minutes until the ink viscosity is 25-35s. After filtering with a 2000-mesh stainless steel filter to remove impurities, a high-insulation and shielding gravure ink is obtained.

[0007] In some embodiments, the mixed solvent is propylene glycol methyl ether acetate, ethyl acetate, and anhydrous ethanol in a volume ratio of 1-4:1-3:1-2.

[0008] In some embodiments, the fluorinated dispersant is one of the following: BYK-110, EFKA-4046, SN270D, or SN26D dispersants.

[0009] In some embodiments, the silane coupling agent is one of the following: KH-792, KH-570, KH-550, and KH-560 silane coupling agents.

[0010] In some embodiments, the leveling agent is one of EFKA-3777, BYK-306, TEKGO450, or TEKGO410 leveling agents.

[0011] In some embodiments, the defoamer is one of BYK-052, TEKGO900, AF700, or TEKGO920 defoamers.

[0012] In some embodiments, the ultrasonic dispersion in S2 has a power of 300-400W, a frequency of 20-25kHz, and a duration of 15-30min; the high-speed shearing has a rotation speed of 3000-3500rpm and a duration of 60-90min.

[0013] In some embodiments, the preparation process of the high-insulation, shielding gravure ink is carried out in a clean environment with an ambient temperature of 20-25°C, humidity of 50-60%, and dust particle level of Class A.

[0014] In some embodiments, the method for preparing the modified boron nitride nanoparticles is as follows: By weight, 48-68 parts of nano boron nitride, 0.5-2.5 parts of 4,4'-dimercaptodiphenyl ether, 5-8 parts of allyltrimethoxysilane, and 190-270 parts of propylene glycol methyl ether acetate were mixed, and 0.1-0.6 parts of α-hydroxy ketone photoinitiator were added. The mixture was then reacted under ultraviolet light with an absorption wavelength of 365 nm for 70-90 minutes. After the reaction was completed, the mixture was filtered and dried to obtain modified nano boron nitride.

[0015] In some embodiments, the α-hydroxyketone liquid photoinitiator is one of photoinitiator 1173, photoinitiator 2959, and photoinitiator 1174.

[0016] Reaction mechanism: α-Hydroxyketone photoinitiators generate active free radicals under 365nm ultraviolet light irradiation, triggering a thiol-olefin addition reaction between the thiol group of 4,4'-dimercaptodiphenyl ether and the active double bond of allyltrimethoxysilane. Simultaneously, the siloxy group of silane undergoes a condensation addition reaction with the hydroxyl group on the surface of boron nitride. The aryl ether dimercapto and siloxane alkyl groups are grafted onto the surface of boron nitride in a molar ratio, forming a uniform distribution of functional groups. These functional groups then undergo directional chemical bonding with the functional groups of the modified polyimide resin, significantly improving the dispersion stability and interfacial bonding strength of boron nitride in the resin.

[0017] Technical effects: This invention provides a method for preparing a high-insulation, shielding gravure ink for precision electronics. Compared with existing technologies, this invention has the following significant advantages: 1. The synergistic grafting of bifunctional groups with precisely matched molar ratios of thiol and epoxy groups completely solves the aggregation problem of nano-boron nitride, significantly optimizes its dispersibility in mixed solvents, accelerates the preparation efficiency of nanoscale composite dispersions, and improves the storage stability of dispersions.

[0018] 2. The uniform molecular layer formed by grafting equimolar functional groups enhances the interfacial bonding force between boron nitride and modified polyimide resin, significantly improves the density of ink film formation, and effectively eliminates structural defects such as micropores and pinholes in the film layer.

[0019] 3. The synergistic grafting of molar ratio-matched aryl ether mercapto groups and siloxane epoxy groups gives boron nitride both excellent thermal stability and insulation properties, further enhancing the insulation performance of the ink and ensuring the long-term retention of insulation indicators under high-temperature environments. Detailed Implementation

[0020] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description is provided in conjunction with embodiments and comparative examples: 1. Surface resistivity: Tested according to KGB / T1410-2006 "Test Methods for Volume Resistivity and Surface Resistivity of Solid Insulating Materials" using a high-resistivity meter.

[0021] 2. Breakdown voltage: Tested in accordance with KGB / T1408.1-2016 "Test methods for electrical strength of insulating materials - Part 1: Test at power frequency".

[0022] 3. Shielding power (OD value): The OD value is measured using an optical densitometer at a wavelength of 550nm. The larger the OD value, the stronger the shielding power. An OD value ≥ 4.0 indicates a full shielding effect.

[0023] Example 1 A method for preparing a high-insulation, shielding gravure ink for precision electronics, comprising the following steps: S1: Weigh 20kg of modified polyimide resin PI-UV-F600 and 6kg of saturated polyester resin PES-200, mix them evenly, add 2kg of organic bentonite, heat to 50℃, premix for 30min to obtain a pre-activated mixture. S2: Weigh 10kg of mixed solvent, add 0.3kg of fluorine-containing dispersant and 0.1kg of silane coupling agent, stir to dissolve, then add 2kg of modified nano boron nitride and 1kg of nano silica, first ultrasonically disperse, then high-speed shear to obtain nanoscale composite dispersion; S3: Cool the pre-activated mixture to 25°C, add the nano-scale composite dispersion, and then add 5 kg of carbon black, 2 kg of micron-sized mica powder, 0.1 kg of leveling agent, and 0.2 kg of defoamer in sequence. Shear at high speed of 1500 rpm for 30 min to obtain the initial mixed ink system. S4: The initial mixed ink system is put into a nano-sand mill for grinding at a temperature of 26°C for 2 hours until the ink fineness is 0.05μm, thus obtaining refined ink; S5: Transfer the refined ink into a curing kettle and cure it for 1 hour at 25°C and 500 rpm with low stirring. Check the viscosity every 30 minutes until the ink viscosity is 25s. After filtering with a 2000-mesh stainless steel filter to remove impurities, a high-insulation, shielding gravure ink is obtained.

[0024] The mixed solvent is propylene glycol methyl ether acetate, ethyl acetate, and anhydrous ethanol in a volume ratio of 1:1:1.

[0025] The fluorinated dispersant is of type BYK-110.

[0026] The silane coupling agent is of type KH-792.

[0027] The leveling agent mentioned is EFKA-3777.

[0028] The defoamer mentioned is BYK-052.

[0029] In S2, the ultrasonic dispersion power is 300W, the frequency is 20kHz, and the time is 15min; the high-speed shearing speed is 3000rpm and the time is 60min.

[0030] The preparation process of the high-insulation, shielding gravure ink is carried out in a clean environment with an ambient temperature of 20°C, humidity of 50%, and dust particle level of A.

[0031] The method for preparing the modified boron nitride nanoparticles is as follows: 48 kg of nano boron nitride, 0.5 kg of 4,4'-dimercaptodiphenyl ether (CAS: 17527-79-6), 5 kg of allyltrimethoxysilane, and 190 kg of propylene glycol methyl ether acetate were mixed, and 0.1 kg of α-hydroxy ketone photoinitiator was added. The mixture was then irradiated with ultraviolet light at an absorption wavelength of 365 nm for 70 minutes. After the reaction was completed, the mixture was filtered and dried to obtain modified nano boron nitride.

[0032] The α-hydroxy ketone liquid photoinitiator is photoinitiator 1173. Example 2

[0033] A method for preparing a high-insulation, shielding gravure ink for precision electronics, comprising the following steps: S1: Weigh 25kg of modified polyimide resin PI-UV-F600 and 8kg of saturated polyester resin PES-200, mix them evenly, add 3kg of organic bentonite, heat to 55℃, premix for 35min to obtain a pre-activated mixture. S2: Weigh 15kg of mixed solvent, add 0.8kg of fluorine-containing dispersant and 0.3kg of silane coupling agent, stir to dissolve, then add 4kg of modified nano boron nitride and 2kg of nano silica, first ultrasonically disperse, then high-speed shear to obtain nanoscale composite dispersion; S3: Cool the pre-activated mixture to 25°C, add the nano-scale composite dispersion, and then add 6 kg of carbon black, 3 kg of micron-sized mica powder, 0.2 kg of leveling agent, and 0.3 kg of defoamer in sequence. Shear at high speed of 1600 rpm for 40 min to obtain the initial mixed ink system. S4: The initial mixed ink system is put into a nano-sand mill for grinding at a temperature of 28°C for 3 hours until the ink fineness is 0.04μm, thus obtaining refined ink; S5: Transfer the refined ink into a curing kettle and cure it for 2 hours at 25°C and 600 rpm with low stirring. Check the viscosity every 30 minutes until the ink viscosity is 30 seconds. After filtering with a 2000-mesh stainless steel filter to remove impurities, a high-insulation, shielding gravure ink is obtained.

[0034] The mixed solvent is propylene glycol methyl ether acetate, ethyl acetate, and anhydrous ethanol in a volume ratio of 2:2:1.

[0035] The fluorinated dispersant is EFKA-4046.

[0036] The silane coupling agent is of type KH-570.

[0037] The leveling agent mentioned is BYK-306.

[0038] The defoamer mentioned is TEKGO900.

[0039] In S2, the ultrasonic dispersion power is 350W, the frequency is 20kHz, and the time is 20min; the high-speed shearing speed is 3100rpm and the time is 70min.

[0040] The preparation process of the high-insulation, shielding gravure ink is carried out in a clean environment with an ambient temperature of 20°C, humidity of 55%, and dust particle level of A.

[0041] The method for preparing the modified boron nitride nanoparticles is as follows: 52 kg of nano boron nitride, 1 kg of 4,4'-dimercaptodiphenyl ether (CAS: 17527-79-6), 6 kg of allyltrimethoxysilane, and 210 kg of propylene glycol methyl ether acetate were mixed, and 0.2 kg of α-hydroxy ketone photoinitiator was added. The mixture was then irradiated with ultraviolet light at an absorption wavelength of 365 nm for 75 minutes. After the reaction was completed, the mixture was filtered and dried to obtain modified nano boron nitride.

[0042] The α-hydroxy ketone liquid photoinitiator is photoinitiator 2959. Example 3

[0043] A method for preparing a high-insulation, shielding gravure ink for precision electronics, comprising the following steps: S1: Weigh 30kg of modified polyimide resin PI-UV-F600 and 10kg of saturated polyester resin PES-200, mix them evenly, add 5kg of organic bentonite, heat to 60℃, and premix for 45min to obtain a pre-activated mixture. S2: Weigh 20kg of mixed solvent, add 1.3kg of fluorine-containing dispersant and 0.7kg of silane coupling agent, stir to dissolve, then add 7kg of modified nano boron nitride and 3kg of nano silica, first ultrasonically disperse, then high-speed shear to obtain nanoscale composite dispersion; S3: Cool the pre-activated mixture to 30°C, add the nano-scale composite dispersion, and then add 8 kg of carbon black, 5 kg of micron-sized mica powder, 0.4 kg of leveling agent, and 0.5 kg of defoamer in sequence. Shear at high speed of 2100 rpm for 50 min to obtain the initial mixed ink system. S4: The initial mixed ink system is put into a nano-sand mill for grinding at a temperature of 30°C for 3 hours until the ink fineness is 0.04μm, thus obtaining refined ink; S5: Transfer the refined ink into a curing kettle and cure it for 2 hours under low-speed stirring conditions of 30℃ and 700rpm. Check the viscosity every 30 minutes until the ink viscosity is 30s. After filtering with a 2000-mesh stainless steel filter to remove impurities, a high-insulation and shielding gravure ink is obtained.

[0044] The mixed solvent is propylene glycol methyl ether acetate, ethyl acetate, and anhydrous ethanol in a volume ratio of 3:2:1.

[0045] The fluorinated dispersant is of type SN270D.

[0046] The silane coupling agent is of type KH-550.

[0047] The leveling agent mentioned is TEKGO450.

[0048] The defoamer mentioned is AF700 type.

[0049] In S2, the ultrasonic dispersion power is 350W, the frequency is 25kHz, and the time is 25min; the high-speed shearing speed is 3400rpm and the time is 80min.

[0050] The preparation process of the high-insulation, shielding gravure ink is carried out in a clean environment with an ambient temperature of 25°C, humidity of 55%, and dust particle level of A.

[0051] The method for preparing the modified boron nitride nanoparticles is as follows: 62 kg of nano boron nitride, 2 kg of 4,4'-dimercaptodiphenyl ether (CAS: 17527-79-6), 7 kg of allyltrimethoxysilane, and 250 kg of propylene glycol methyl ether acetate were mixed, and 0.5 kg of α-hydroxy ketone photoinitiator was added. The mixture was then irradiated with ultraviolet light at an absorption wavelength of 365 nm for 85 minutes. After the reaction was completed, the mixture was filtered and dried to obtain modified nano boron nitride.

[0052] The α-hydroxy ketone liquid photoinitiator is photoinitiator 2959. Example 4

[0053] A method for preparing a high-insulation, shielding gravure ink for precision electronics, comprising the following steps: S1: Weigh 35kg of modified polyimide resin PI-UV-F600 and 12kg of saturated polyester resin PES-200, mix them evenly, add 6kg of organic bentonite, heat to 65℃, premix for 50min to obtain a pre-activated mixture. S2: Weigh 25kg of mixed solvent, add 1.5kg of fluorine-containing dispersant and 0.8kg of silane coupling agent, stir to dissolve, then add 8kg of modified nano boron nitride and 4kg of nano silica, first ultrasonically disperse, then high-speed shear to obtain nanoscale composite dispersion; S3: Cool the pre-activated mixture to 30°C, add the nano-scale composite dispersion, and then add 10kg carbon black, 6kg micron-sized mica powder, 0.5kg leveling agent, and 0.6kg defoamer in sequence. Shear at high speed of 2200rpm for 60min to obtain the initial mixed ink system. S4: The initial mixed ink system is put into a nano-sand mill for grinding at a temperature of 32°C for 4 hours until the ink fineness is 0.03μm, thus obtaining refined ink; S5: Transfer the refined ink into a curing kettle and cure it for 3 hours at 30°C and 800 rpm with low stirring. Check the viscosity every 30 minutes until the ink viscosity is 35s. After filtering with a 2000-mesh stainless steel filter to remove impurities, a high-insulation, shielding gravure ink is obtained.

[0054] The mixed solvent is propylene glycol methyl ether acetate, ethyl acetate, and anhydrous ethanol in a volume ratio of 4:3:2.

[0055] The fluorinated dispersant is an SN26D type dispersant.

[0056] The silane coupling agent is KH-560 type silane coupling agent.

[0057] The leveling agent mentioned is TEKGO410 leveling agent.

[0058] The defoamer mentioned is TEKGO920 type defoamer.

[0059] In S2, the ultrasonic dispersion power is 400W, the frequency is 25kHz, and the time is 30min; the high-speed shearing speed is 3500rpm and the time is 90min.

[0060] The preparation process of the high-insulation, shielding gravure ink is carried out in a clean environment with an ambient temperature of 25°C, humidity of 60%, and dust particle level of A.

[0061] The method for preparing the modified boron nitride nanoparticles is as follows: 68 kg of nano boron nitride, 2.5 kg of 4,4'-dimercaptodiphenyl ether (CAS: 17527-79-6), 8 kg of allyltrimethoxysilane, and 270 kg of propylene glycol methyl ether acetate were mixed, and 0.6 kg of α-hydroxy ketone photoinitiator was added. The mixture was then irradiated with ultraviolet light at an absorption wavelength of 365 nm for 90 minutes. After the reaction was completed, the mixture was filtered and dried to obtain modified nano boron nitride.

[0062] The α-hydroxyketone liquid photoinitiator is photoinitiator 1174.

[0063] Comparative Example 1 A method for preparing a high-insulation, shielding gravure ink for precision electronics, comprising the following steps: S1: Weigh 20kg of modified polyimide resin PI-UV-F600 and 6kg of saturated polyester resin PES-200, mix them evenly, add 2kg of organic bentonite, heat to 50℃, premix for 30min to obtain a pre-activated mixture. S2: Weigh 10kg of mixed solvent, add 0.3kg of fluorine-containing dispersant and 0.1kg of silane coupling agent, stir to dissolve, then add 2kg of nano boron nitride and 1kg of nano silica, first ultrasonically disperse, then high-speed shear to obtain nanoscale composite dispersion; S3: Cool the pre-activated mixture to 25°C, add the nano-scale composite dispersion, and then add 5 kg of carbon black, 2 kg of micron-sized mica powder, 0.1 kg of leveling agent, and 0.2 kg of defoamer in sequence. Shear at high speed of 1500 rpm for 30 min to obtain the initial mixed ink system. S4: The initial mixed ink system is put into a nano-sand mill for grinding at a temperature of 26°C for 2 hours until the ink fineness is 0.05μm, thus obtaining refined ink; S5: Transfer the refined ink into a curing kettle and cure it for 1 hour at 25°C and 500 rpm with low stirring. Check the viscosity every 30 minutes until the ink viscosity is 25s. After filtering with a 2000-mesh stainless steel filter to remove impurities, a high-insulation, shielding gravure ink is obtained.

[0064] The mixed solvent is propylene glycol methyl ether acetate, ethyl acetate, and anhydrous ethanol in a volume ratio of 1:1:1.

[0065] The fluorinated dispersant is of type BYK-110.

[0066] The silane coupling agent is of type KH-792.

[0067] The leveling agent mentioned is EFKA-3777.

[0068] The defoamer mentioned is BYK-052.

[0069] In S2, the ultrasonic dispersion power is 300W, the frequency is 20kHz, and the time is 15min; the high-speed shearing speed is 3000rpm and the time is 60min.

[0070] The preparation process of the high-insulation, shielding gravure ink is carried out in a clean environment with an ambient temperature of 20°C, humidity of 50%, and dust particle level of A.

[0071] Comparative Example 2 A method for preparing a high-insulation, shielding gravure ink for precision electronics, comprising the following steps: S1: Weigh 20kg of modified polyimide resin PI-UV-F600 and 6kg of saturated polyester resin PES-200, mix them evenly, add 2kg of organic bentonite, heat to 50℃, premix for 30min to obtain a pre-activated mixture. S2: Weigh 10kg of mixed solvent, add 0.3kg of fluorine-containing dispersant and 0.1kg of silane coupling agent, stir to dissolve, then add 2kg of modified nano boron nitride and 1kg of nano silica, first ultrasonically disperse, then high-speed shear to obtain nanoscale composite dispersion; S3: Cool the pre-activated mixture to 25°C, add the nano-scale composite dispersion, and then add 5 kg of carbon black, 2 kg of micron-sized mica powder, 0.1 kg of leveling agent, and 0.2 kg of defoamer in sequence. Shear at high speed of 1500 rpm for 30 min to obtain the initial mixed ink system. S4: The initial mixed ink system is put into a nano-sand mill for grinding at a temperature of 26°C for 2 hours until the ink fineness is 0.05μm, thus obtaining refined ink; S5: Transfer the refined ink into a curing kettle and cure it for 1 hour at 25°C and 500 rpm with low stirring. Check the viscosity every 30 minutes until the ink viscosity is 25s. After filtering with a 2000-mesh stainless steel filter to remove impurities, a high-insulation, shielding gravure ink is obtained.

[0072] The mixed solvent is propylene glycol methyl ether acetate, ethyl acetate, and anhydrous ethanol in a volume ratio of 1:1:1.

[0073] The fluorinated dispersant is of type BYK-110.

[0074] The silane coupling agent is of type KH-792.

[0075] The leveling agent mentioned is EFKA-3777.

[0076] The defoamer mentioned is BYK-052.

[0077] In S2, the ultrasonic dispersion power is 300W, the frequency is 20kHz, and the time is 15min; the high-speed shearing speed is 3000rpm and the time is 60min.

[0078] The preparation process of the high-insulation, shielding gravure ink is carried out in a clean environment with an ambient temperature of 20°C, humidity of 50%, and dust particle level of A.

[0079] The method for preparing the modified boron nitride nanoparticles is as follows: 48 kg of nano boron nitride, 5 kg of allyltrimethoxysilane, and 190 kg of propylene glycol methyl ether acetate were mixed, and 0.1 kg of α-hydroxy ketone photoinitiator was added. The mixture was then irradiated with ultraviolet light with an absorption wavelength of 365 nm for 70 minutes. After the reaction was completed, the mixture was filtered and dried to obtain modified nano boron nitride.

[0080] The α-hydroxy ketone liquid photoinitiator is photoinitiator 1173.

[0081] Comparative Example 3 A method for preparing a high-insulation, shielding gravure ink for precision electronics, comprising the following steps: S1: Weigh 20kg of modified polyimide resin PI-UV-F600 and 6kg of saturated polyester resin PES-200, mix them evenly, add 2kg of organic bentonite, heat to 50℃, premix for 30min to obtain a pre-activated mixture. S2: Weigh 10kg of mixed solvent, add 0.3kg of fluorine-containing dispersant and 0.1kg of silane coupling agent, stir to dissolve, then add 2kg of modified nano boron nitride and 1kg of nano silica, first ultrasonically disperse, then high-speed shear to obtain nanoscale composite dispersion; S3: Cool the pre-activated mixture to 25°C, add the nano-scale composite dispersion, and then add 5 kg of carbon black, 2 kg of micron-sized mica powder, 0.1 kg of leveling agent, and 0.2 kg of defoamer in sequence. Shear at high speed of 1500 rpm for 30 min to obtain the initial mixed ink system. S4: The initial mixed ink system is put into a nano-sand mill for grinding at a temperature of 26°C for 2 hours until the ink fineness is 0.05μm, thus obtaining refined ink; S5: Transfer the refined ink into a curing kettle and cure it for 1 hour at 25°C and 500 rpm with low stirring. Check the viscosity every 30 minutes until the ink viscosity is 25s. After filtering with a 2000-mesh stainless steel filter to remove impurities, a high-insulation, shielding gravure ink is obtained.

[0082] The mixed solvent is propylene glycol methyl ether acetate, ethyl acetate, and anhydrous ethanol in a volume ratio of 1:1:1.

[0083] The fluorinated dispersant is of type BYK-110.

[0084] The silane coupling agent is of type KH-792.

[0085] The leveling agent mentioned is EFKA-3777.

[0086] The defoamer mentioned is BYK-052.

[0087] In S2, the ultrasonic dispersion power is 300W, the frequency is 20kHz, and the time is 15min; the high-speed shearing speed is 3000rpm and the time is 60min.

[0088] The preparation process of the high-insulation, shielding gravure ink is carried out in a clean environment with an ambient temperature of 20°C, humidity of 50%, and dust particle level of A.

[0089] The method for preparing the modified boron nitride nanoparticles is as follows: 48 kg of nano boron nitride, 0.5 kg of 4,4'-dimercaptodiphenyl ether (CAS: 17527-79-6), and 190 kg of propylene glycol methyl ether acetate were mixed, and 0.1 kg of α-hydroxy ketone photoinitiator was added. The mixture was then irradiated with ultraviolet light at an absorption wavelength of 365 nm for 70 minutes. After the reaction was completed, the mixture was filtered and dried to obtain modified nano boron nitride.

[0090] The α-hydroxy ketone liquid photoinitiator is photoinitiator 1173.

[0091] Table 1. Detection results of surface resistivity, breakdown voltage, and hiding power (OD value) of gravure inks in the examples and comparative examples. Surface resistivity (Ω·cm) Breakdown voltage (kV / mm) Shielding power OD value Example 1 <![CDATA[1.22×10 13 ]]> 21.3 4.48 Example 2 <![CDATA[1.19×10 13 ]]> 21.6 4.51 Example 3 <![CDATA[1.13×10 13 ]]> 22.1 4.56 Example 4 <![CDATA[1.11×10 13 ]]> 22.4 4.59 Comparative Example 1 <![CDATA[5.83×10 11 ]]> 12.7 3.35 Comparative Example 2 <![CDATA[0.34×10 13 ]]> 17.3 3.89 Comparative Example 3 <![CDATA[0.56×10 13 ]]> 18.0 4.02 Based on the above data analysis, after the application of modified nano boron nitride, the core indicators of the ink, such as surface resistance, breakdown voltage, and hiding power (OD value), all reached the optimal values ​​in the patent data sheet. The preparation time of the composite dispersion was shortened by more than 30% compared with the conventional process, and the room temperature storage stability of the dispersion was improved to more than 6 months compared with the original system. One of the core innovations of this solution is the thiol-olefin addition reaction, which enables the aryl ether thiol group of 4,4'-dimercaptodiphenyl ether and the allyl group of allyltrimethoxysilane to be quantitatively and uniformly grafted on the boron nitride surface. This avoids the problem of uneven grafting caused by excessive monofunctional groups, and achieves a synergistic improvement of boron nitride dispersibility and ink insulation and thermal stability (1+1>2). This is also the key factor for the ink film density index to reach the optimal value in the data sheet.

[0092] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing a high-insulation, shielding gravure ink for precision electronics, comprising the following steps, in parts by weight: S1: Weigh 20-35 parts of modified polyimide resin PI-UV-F600 and 6-12 parts of saturated polyester resin PES-200 by weight, mix them evenly, add 2-6 parts of organic bentonite, heat to 50-65℃, premix for 30-50 minutes to obtain a pre-activated mixture. S2: Weigh 10-25 parts of mixed solvent, add 0.3-1.5 parts of fluorine-containing dispersant and 0.1-0.8 parts of silane coupling agent, stir to dissolve, add 2-8 parts of modified nano boron nitride and 1-4 parts of nano silica, first ultrasonically disperse, then high-speed shear to obtain nanoscale composite dispersion; S3: Cool the pre-activated mixture to 25-30℃, add the nano-scale composite dispersion, and then add 5-10 parts of carbon black, 2-6 parts of micron-sized mica powder, 0.1-0.5 parts of leveling agent, and 0.2-0.6 parts of defoamer in sequence. Shear at high speed at 1500-2200 rpm for 30-60 minutes to obtain the initial mixed ink system. S4: The initial mixed ink system is put into a nano-sand mill for grinding. The grinding temperature is 26-32℃ and the grinding time is 2-4h until the ink fineness is 0.03-0.05μm to obtain refined ink. S5: Transfer the refined ink into a curing kettle and cure it for 1-3 hours at a low speed of 25-30℃ and 500-800rpm. Check the viscosity every 30 minutes until the ink viscosity is 25-35s. After filtering with a 2000-mesh stainless steel filter to remove impurities, a high-insulation and shielding gravure ink is obtained. The modified boron nitride nanoparticles are prepared by reacting boron nitride nanoparticles, 4,4'-dimercaptodiphenyl ether, allyltrimethoxysilane, and α-hydroxy ketone photoinitiators under ultraviolet light irradiation.

2. The method for preparing a high-insulation, shielding gravure ink for precision electronics according to claim 1, characterized in that: The mixed solvent is propylene glycol methyl ether acetate, ethyl acetate, and anhydrous ethanol in a volume ratio of 1-4:1-3:1-2.

3. The method for preparing a high-insulation, shielding gravure ink for precision electronics according to claim 1, characterized in that: The fluorinated dispersant is one of the following: BYK-110, EFKA-4046, SN270D, or SN26D.

4. The method for preparing a high-insulation, shielding gravure ink for precision electronics according to claim 1, characterized in that: The silane coupling agent is one of the following: KH-792, KH-570, KH-550, and KH-560.

5. The method for preparing a high-insulation, shielding gravure ink for precision electronics according to claim 1, characterized in that: The leveling agent is one of the following: EFKA-3777, BYK-306, TEKGO450, or TEKGO410.

6. The method for preparing a high-insulation, shielding gravure ink for precision electronics according to claim 1, characterized in that: The defoamer is one of the following: BYK-052, TEKGO900, AF700, or TEKGO920.

7. The method for preparing a high-insulation, shielding gravure ink for precision electronics according to claim 1, characterized in that: In S2, the ultrasonic dispersion power is 300-400W, the frequency is 20-25kHz, and the time is 15-30min; the high-speed shearing speed is 3000-3500rpm, and the time is 60-90min.

8. The method for preparing a high-insulation, shielding gravure ink for precision electronics according to claim 1, characterized in that: The preparation process of the high-insulation, shielding gravure ink is carried out in a clean environment with an ambient temperature of 20-25℃, humidity of 50-60%, and dust particle level of A.

9. The method for preparing a high-insulation, shielding gravure ink for precision electronics according to claim 1, characterized in that: The method for preparing the modified boron nitride nanoparticles is as follows: By weight, 48-68 parts of nano boron nitride, 0.5-2.5 parts of 4,4'-dimercaptodiphenyl ether, 5-8 parts of allyltrimethoxysilane, and 190-270 parts of propylene glycol methyl ether acetate were mixed, and 0.1-0.6 parts of α-hydroxy ketone photoinitiator were added. The mixture was then reacted under ultraviolet light with an absorption wavelength of 365 nm for 70-90 minutes. After the reaction was completed, the mixture was filtered and dried to obtain modified nano boron nitride.

10. The method for preparing a high-insulation, shielding gravure ink for precision electronics according to claim 9, characterized in that: The α-hydroxy ketone liquid photoinitiator is one of photoinitiator 1173, photoinitiator 2959, and photoinitiator 1174.