Low-loss circuit board ink and preparation method thereof

Abstract

The present invention relates to the technical field of inks, and in particular to a low-loss circuit board ink and a preparation method thereof. The invention comprises the following steps: selecting polyurethane acrylate as a primary light-curing resin, introducing polymethyl methacrylate as a raw material, using dicyclopentadiene-phenol epoxy resin as a hardener, and using silicon micropowder as a filler; selecting hydroxy-terminated polybutadiene as a raw material and isophorone diisocyanate to synthesize a prepolymer under the action of a catalyst; using hydroxyethyl acrylate and a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer as end-capping agents to synthesize a composite polyurethane acrylate; firstly carboxylating the silicon micropowder, and then performing a modification treatment with the hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer to improve the adhesion of the silicon micropowder and prevent the silicon micropowder from falling off under conditions such as external impact, thereby improving various properties of the ink.

Description

Technical Field

[0001] The present invention relates to the technical field of inks, in particular to low-loss circuit board ink and a preparation method thereof. Background Art

[0002] Printed circuit boards are substrates for connecting and installing various microelectronic devices. With the advent of the 5G era, the requirements for signal transmission speed are getting higher and higher, and the requirements for signal integrity of printed circuit boards are also increasing accordingly.

[0003] During the manufacturing process of printed circuit boards, solder mask ink is usually printed on their surface to prevent welding damage. Therefore, the performance of the solder mask ink will directly affect the yield rate of subsequent mounted devices, thereby affecting the reliability of the printed circuit board. At the same time, the heat resistance, water resistance, and corrosion resistance of the solder mask ink are also closely related to the service life of the printed circuit board. Summary of the Invention

[0004] The object of the present invention is to provide a low-loss circuit board ink and a preparation method thereof, so as to solve the problems in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A method for preparing low-loss circuit board ink comprises the following steps:

[0007] S1: polymethyl methacrylate, composite polyurethane acrylate, reactive diluent, modified silica powder, photoinitiator, and solvent are stirred and mixed, and then ground and sieved to obtain a mixed base material A;

[0008] S2: mixing dicyclopentadiene-phenol epoxy resin, additives, and pigments, grinding and sieving to obtain a mixed base material B;

[0009] S3: The mixed base material A and the mixed base material B are put into a high-speed disperser for dispersion treatment to obtain a low-loss circuit board ink.

[0010] Furthermore, the working conditions of the dispersion treatment are: temperature of 55-65°C and time of 1-2 hours.

[0011] Furthermore, the auxiliary agent is a dispersant, a leveling agent, and a defoaming agent mixed in a mass ratio of 1:1:1.

[0012] Furthermore, the active diluent is one or a combination of ditrimethylolpropane acrylate, dipropylene glycol diacrylate, and propane trimethanol triacrylate.

[0013] Furthermore, the mass ratio of the mixed base material A to the mixed base material B is 85:15.

[0014] Furthermore, the raw material composition of the mixed base A is, in parts by weight: 11-16 parts of polymethyl methacrylate, 22-42 parts of composite polyurethane acrylate, 1-3 parts of active diluent, 1-3 parts of photoinitiator, 4-9 parts of modified silica powder, and 10-20 parts of solvent.

[0015] Furthermore, in the mixed base B, the mass ratio of dicyclopentadiene-phenol epoxy resin, additives, and pigment is 10:2:3.

[0016] Furthermore, the preparation of composite polyurethane acrylate comprises the following steps:

[0017] Under a nitrogen atmosphere, the hydroxy-terminated polybutadiene is kept in an oil bath at 105°C for 2 hours, cooled to 18-25°C, ethyl acetate is added, a mixture of isophorone diisocyanate and ethyl acetate is added, dibutyltin dilaurate and p-hydroxyanisole are added, and the mixture is kept in an oil bath at 38-42°C for 30-40 minutes, hydroxyethyl acrylate, a mixture of hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer and ethyl acetate are added, dibutyltin dilaurate and p-hydroxyanisole are added, the temperature is raised to 68-72°C and kept for 1-2 hours to obtain a composite polyurethane acrylate.

[0018] Furthermore, the preparation of modified silicon powder includes the following steps:

[0019] The preparation of the modified silicon micropowder comprises the following steps:

[0020] (1) 3-aminopropyltriethoxysilane, succinic anhydride, and N,N-dimethylformamide were mixed and stirred for 2-3 hours, and the temperature was raised to 50-60°C. A mixture of silicon micropowder and N,N-dimethylformamide was added, and deionized water was added. The mixture was stirred for 4-5 hours, centrifuged, washed with alcohol, and dried to obtain carboxylated silicon micropowder.

[0021] (2) Under nitrogen atmosphere, hydroxy-containing polyaryletherketone-polydimethylsiloxane copolymer, carboxylated silicon micropowder, p-toluenesulfonic acid, and N,N-dimethylformamide are mixed, kept at 140-145°C for 4-5 hours, cooled, filtered, washed, and dried to obtain modified silicon micropowder.

[0022] Furthermore, the preparation of the hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer comprises the following steps:

[0023] 1) Under a nitrogen atmosphere, 4-(4-hydroxyphenyl)-2,3-naphthyridin-1-one, 4,4'-difluorobenzophenone, potassium carbonate, N-methylpyrrolidone, and toluene were mixed, heated to 148-152°C and kept for 1 hour, then heated to 178-182°C and kept for 2-3 hours, cooled to 18-25°C, and propargyl bromide was added. The mixture was heated to 58-62°C and kept for 23-24 hours. The mixture was washed with hot water, filtered, and dried. Chloroform and ethanol were added to obtain a polyaryl ether ketone oligomer containing an alkynyl terminal group.

[0024] 2) Mix isopropyl alcohol and epoxy-terminated polydimethylsiloxane, add deionized water and sodium azide, adjust the pH of the solution to 5, stir at 45-50°C overnight, adjust the pH of the solution to 7, extract with pentane 3-4 times, wash, and dry to obtain azido polydimethylsiloxane;

[0025] 3) Under a nitrogen atmosphere, a poly(aryl ether ketone) oligomer containing an alkynyl terminal group, polydimethylsiloxane azide, N-methylpyrrolidone, and tetrahydrofuran are mixed, copper sulfate and sodium ascorbate are added, the mixture is heated to 58-62°C and kept warm for 7-8 hours, poured into ethanol, dried, and extracted in a Soxhlet extractor with acetone as the extractant. The mixture is dried to obtain a hydroxyl-containing poly(aryl ether ketone)-polydimethylsiloxane copolymer.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention provides a low-loss circuit board ink and a preparation method thereof, and produces a high-reliability solder mask ink with good high-temperature resistance, strong corrosion resistance, and good hydrophobicity. When applied to the surface solder mask process of printed circuit boards such as high-layer and high-density packaging printed circuit boards, arbitrary interconnection boards, and server boards, the ink has the characteristics of high stability and low dielectric loss.

[0028] In the present invention, polyurethane acrylate, which has both the excellent flexibility of polyurethane and the excellent weather resistance and chemical resistance of acrylate, is selected as the main light-curing resin, polymethyl methacrylate is introduced as the raw material, dicyclopentadiene-phenol epoxy resin is used as the hardener, and silica powder is used as the filler. Under the action of an initiator, a light- and heat-dual-curing ink is prepared to improve the performance of the ink.

[0029] In order to further improve the high temperature resistance of the ink, the present invention selects terminal hydroxyl polybutadiene with a flexible long carbon chain structure as a raw material, and synthesizes a prepolymer with isophorone diisocyanate under the action of a catalyst, and uses hydroxyethyl acrylate and a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer as a capping agent to synthesize a photocurable composite polyurethane acrylate with good mechanical strength, high and low temperature resistance, and hydrophobicity; wherein the hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer uses diazinone biphenyl bisphenol and difluoroketone as raw materials, and is sequentially subjected to nucleophilic condensation and bromopropyne capping to obtain a polyaryletherketone oligomer with an alkynyl group at the end of the molecular chain, which is then prepared by click grafting azidized polydimethylsiloxane, thereby greatly improving the high and low temperature resistance and hydrophobicity of the ink.

[0030] In order to improve the uniformity of the dispersion of filler silicon micropowder in the ink, the silicon micropowder is first carboxylated and then modified with a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer to improve the adhesion of the silicon micropowder and prevent the silicon micropowder from falling off under conditions such as external force impact, thereby improving the high temperature resistance, water resistance and corrosion resistance of the ink. DETAILED DESCRIPTION

[0031] The following will provide a clear and complete description of the technical solutions of the present invention in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0032] It should be noted that if the embodiments of the present invention involve directional indications such as up, down, left, right, front, and back, such directional indications are only used to explain a specific posture, such as the relative position relationship between components, the movement status, etc. If the specific posture changes, the directional indication will also change accordingly. In addition, the technical solutions between the various embodiments may be combined with each other, but they must be based on the premise that they can be implemented by ordinary technicians in this field. If the combination of technical solutions is mutually inconsistent or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0033] The technical solutions of the present invention are further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely used to explain the present invention and are not intended to limit the present invention.

[0034] Example 1: A method for preparing a low-loss circuit board ink, comprising the following steps:

[0035] S1: polymethyl methacrylate, composite polyurethane acrylate, reactive diluent, modified silica powder, photoinitiator, and solvent are stirred and mixed in a mixer, and then ground and sieved to obtain a mixed base material A;

[0036] The raw material composition of the mixed base A is as follows: 11 parts of polymethyl methacrylate, 22 parts of composite polyurethane acrylate, 1 part of reactive diluent, 1 part of photoinitiator, 4 parts of modified silica powder, and 10 parts of solvent, calculated by weight.

[0037] The preparation of the composite polyurethane acrylate comprises the following steps:

[0038] Under a nitrogen atmosphere, 3 g of hydroxy-terminated polybutadiene was kept in an oil bath at 105° C. for 2 h, cooled to 18° C., 3 g of ethyl acetate was added, a mixture of 0.4 g of isophorone diisocyanate and 1 g of ethyl acetate was added, 1.67 mg of dibutyltin dilaurate and 3.4 mg of p-hydroxyanisole were added, and the mixture was kept in an oil bath at 38° C. for 40 min, 0.2 g of hydroxyethyl acrylate, 0.3 g of a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer and 1 g of ethyl acetate was added, 3 mg of dibutyltin dilaurate and 4 mg of p-hydroxyanisole were added, and the mixture was heated to 68° C. and kept for 2 h to obtain a composite polyurethane acrylate;

[0039] The preparation of the modified silicon micropowder comprises the following steps:

[0040] (1) 1 mmol 3-aminopropyltriethoxysilane, 1 mmol succinic anhydride, and 20 mL N, N-dimethylformamide were mixed and stirred for 2 h. The mixture was heated to 50 °C, and a mixture of 2 g silicon powder and 18 mL N, N-dimethylformamide was added. 2 mL deionized water was added and the mixture was stirred for 4 h. The mixture was centrifuged, washed with alcohol, and dried to obtain carboxylated silicon powder.

[0041] (2) Under nitrogen atmosphere, 2.8 g of hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer, 1.6 g of carboxylated silicon micropowder, 0.1 g of p-toluenesulfonic acid, and 50 mL of N,N-dimethylformamide were mixed, kept at 140 °C for 5 h, cooled, filtered, washed, and dried to obtain modified silicon micropowder;

[0042] The preparation of the hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer comprises the following steps:

[0043] 1) Under a nitrogen atmosphere, 2.4 g of 4-(4-hydroxyphenyl)-2,3-naphthyridin-1-one, 1.6 g of 4,4'-difluorobenzophenone, 1.7 g of potassium carbonate, 15 mL of N,N-dimethylformamide, and 2 mL of toluene were mixed, heated to 148°C and held for 1 h, then heated to 182°C and held for 2 h, cooled to 18°C, 1.2 g of propargyl bromide was added, and the mixture was heated to 58°C and held for 23 h. The mixture was washed with hot water, filtered, and dried, and chloroform and ethanol were added to obtain a polyaryl ether ketone oligomer containing an alkynyl terminal group.

[0044] 2) Mix 80 mL of isopropanol and 2.4 g of epoxy-terminated polydimethylsiloxane, add 15 mL of deionized water and 1.04 g of sodium azide, adjust the pH of the solution to 5, stir at 45°C overnight, adjust the pH of the solution to 7, extract three times with 30 mL of pentane, wash, and dry to obtain azido polydimethylsiloxane;

[0045] 3) Under a nitrogen atmosphere, 0.5 g of a terminal alkyne-containing poly(aryl ether ketone) oligomer, 1.5 g of azidated polydimethylsiloxane, 7.5 mL of N-methylpyrrolidone, and 7.5 mL of tetrahydrofuran were mixed, 0.02 g of copper sulfate and 0.03 g of sodium ascorbate were added, the mixture was heated to 58°C and maintained for 8 h, poured into ethanol, dried, and extracted in a Soxhlet extractor with acetone as the extractant. The mixture was dried to obtain a hydroxyl-containing poly(aryl ether ketone)-polydimethylsiloxane copolymer.

[0046] The reactive diluent is dipropylene glycol diacrylate;

[0047] S2: mixing dicyclopentadiene-phenol epoxy resin, additives, and pigments, grinding and sieving to obtain a mixed base material B;

[0048] In the mixed base B, the mass ratio of dicyclopentadiene-phenol epoxy resin, additives, and pigment is 10:2:3;

[0049] The additives are dispersant, leveling agent and defoamer mixed in a mass ratio of 1:1:1;

[0050] S3: Put the mixed base material A and the mixed base material B into a high-speed disperser for dispersion treatment to obtain a low-loss circuit board ink; the mass ratio of the mixed base material A to the mixed base material B is 85:15; the working conditions of the dispersion treatment are: temperature 55°C, time 2 hours.

[0051] Example 2: A method for preparing low-loss circuit board ink, comprising the following steps:

[0052] S1: polymethyl methacrylate, composite polyurethane acrylate, reactive diluent, modified silica powder, photoinitiator, and solvent are stirred and mixed in a mixer, and then ground and sieved to obtain a mixed base material A;

[0053] The raw material composition of the mixed base A is as follows: 13 parts of polymethyl methacrylate, 31 parts of composite polyurethane acrylate, 2 parts of reactive diluent, 2 parts of photoinitiator, 6 parts of modified silica powder, and 15 parts of solvent, calculated by weight.

[0054] The preparation of the composite polyurethane acrylate comprises the following steps:

[0055] Under a nitrogen atmosphere, 3 g of hydroxyl-terminated polybutadiene was kept in an oil bath at 105°C for 2 h, cooled to 20°C, added with 3 g of ethyl acetate, added with a mixture of 0.4 g of isophorone diisocyanate and 1 g of ethyl acetate, added with 1.67 mg of dibutyltin dilaurate and 3.4 mg of p-hydroxyanisole, and kept in an oil bath at 40°C for 35 min, added with a mixture of 0.2 g of hydroxyethyl acrylate, 0.3 g of a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer and 1 g of ethyl acetate, added with 3 mg of dibutyltin dilaurate and 4 mg of p-hydroxyanisole, and heated to 70°C and kept for 1.5 h to obtain a composite polyurethane acrylate;

[0056] The preparation of the modified silicon micropowder comprises the following steps:

[0057] (1) Mix 1 mmol of 3-aminopropyltriethoxysilane, 1 mmol of succinic anhydride, and 20 mL of N,N-dimethylformamide, stir for 2.5 h, heat to 55 °C, add a mixture of 2 g of silicon micropowder and 18 mL of N,N-dimethylformamide, add 2 mL of deionized water, continue stirring for 4.5 h, centrifuge, wash with alcohol, and dry to obtain carboxylated silicon micropowder;

[0058] (2) Under nitrogen atmosphere, 2.8 g of hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer, 1.6 g of carboxylated silicon micropowder, 0.1 g of p-toluenesulfonic acid, and 50 mL of N,N-dimethylformamide were mixed, kept at 143 °C for 4.5 h, cooled, filtered, washed, and dried to obtain modified silicon micropowder;

[0059] The preparation of the hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer comprises the following steps:

[0060] 1) Under a nitrogen atmosphere, 2.4 g of 4-(4-hydroxyphenyl)-2,3-naphthyridin-1-one, 1.6 g of 4,4'-difluorobenzophenone, 1.7 g of potassium carbonate, 15 mL of N,N-dimethylformamide, and 2 mL of toluene were mixed, heated to 150°C and maintained for 1 h, then heated to 180°C and maintained for 2.5 h, cooled to 20°C, 1.2 g of propargyl bromide was added, and the temperature was raised to 60°C and maintained for 23.5 h. The product was washed with hot water, filtered, dried, and then chloroform and ethanol were added to obtain a polyaryl ether ketone oligomer containing an alkynyl terminal group.

[0061] 2) Mix 80 mL of isopropanol and 2.4 g of epoxy-terminated polydimethylsiloxane, add 15 mL of deionized water and 1.04 g of sodium azide, adjust the pH of the solution to 5, stir at 48°C overnight, adjust the pH of the solution to 7, extract three times with 30 mL of pentane, wash, and dry to obtain azido polydimethylsiloxane;

[0062] 3) Under a nitrogen atmosphere, 0.5 g of a terminal alkyne-containing poly(aryl ether ketone) oligomer, 1.5 g of azidated polydimethylsiloxane, 7.5 mL of N-methylpyrrolidone, and 7.5 mL of tetrahydrofuran were mixed, 0.02 g of copper sulfate and 0.03 g of sodium ascorbate were added, the mixture was heated to 60°C and maintained for 7.5 h, poured into ethanol, dried, and extracted in a Soxhlet extractor with acetone as the extractant. The mixture was dried to obtain a hydroxyl-containing poly(aryl ether ketone)-polydimethylsiloxane copolymer.

[0063] The reactive diluent is dipropylene glycol diacrylate;

[0064] S2: mixing dicyclopentadiene-phenol epoxy resin, additives, and pigments, grinding and sieving to obtain a mixed base material B;

[0065] In the mixed base B, the mass ratio of dicyclopentadiene-phenol epoxy resin, additives, and pigment is 10:2:3;

[0066] The additives are dispersant, leveling agent and defoamer mixed in a mass ratio of 1:1:1;

[0067] S3: Put the mixed base material A and the mixed base material B into a high-speed disperser for dispersion treatment to obtain a low-loss circuit board ink; the mass ratio of the mixed base material A to the mixed base material B is 85:15; the working conditions of the dispersion treatment are: temperature 60°C, time 1.5 hours.

[0068] Example 3: A method for preparing low-loss circuit board ink, comprising the following steps:

[0069] S1: polymethyl methacrylate, composite polyurethane acrylate, reactive diluent, modified silica powder, photoinitiator, and solvent are stirred and mixed in a mixer, and then ground and sieved to obtain a mixed base material A;

[0070] The raw material composition of the mixed base A is as follows: 16 parts of polymethyl methacrylate, 42 parts of composite polyurethane acrylate, 3 parts of reactive diluent, 3 parts of photoinitiator, 9 parts of modified silica powder, and 20 parts of solvent, in parts by weight;

[0071] The preparation of the composite polyurethane acrylate comprises the following steps:

[0072] Under a nitrogen atmosphere, 3 g of hydroxyl-terminated polybutadiene was kept in an oil bath at 105° C. for 2 h, cooled to 25° C., added with 3 g of ethyl acetate, a mixture of 0.4 g of isophorone diisocyanate and 1 g of ethyl acetate, 1.67 mg of dibutyltin dilaurate and 3.4 mg of p-hydroxyanisole, and kept in an oil bath at 42° C. for 30 min, and a mixture of 0.2 g of hydroxyethyl acrylate, 0.3 g of a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer and 1 g of ethyl acetate was added, 3 mg of dibutyltin dilaurate and 4 mg of p-hydroxyanisole were added, and the mixture was heated to 72° C. and kept for 1 h to obtain a composite polyurethane acrylate;

[0073] The preparation of the modified silicon micropowder comprises the following steps:

[0074] (1) Mix 1 mmol of 3-aminopropyltriethoxysilane, 1 mmol of succinic anhydride, and 20 mL of N,N-dimethylformamide, stir for 3 h, heat to 60 °C, add a mixture of 2 g of silicon micropowder and 18 mL of N,N-dimethylformamide, add 2 mL of deionized water, continue stirring for 5 h, centrifuge, wash with alcohol, and dry to obtain carboxylated silicon micropowder;

[0075] (2) Under nitrogen atmosphere, 2.8 g of hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer, 1.6 g of carboxylated silicon micropowder, 0.1 g of p-toluenesulfonic acid, and 50 mL of N,N-dimethylformamide were mixed, kept at 145 °C for 4 h, cooled, filtered, washed, and dried to obtain modified silicon micropowder;

[0076] The preparation of the hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer comprises the following steps:

[0077] 1) Under a nitrogen atmosphere, 2.4 g of 4-(4-hydroxyphenyl)-2,3-naphthyridin-1-one, 1.6 g of 4,4'-difluorobenzophenone, 1.7 g of potassium carbonate, 15 mL of N,N-dimethylformamide, and 2 mL of toluene were mixed, heated to 152°C and held for 1 h, then heated to 182°C and held for 2 h, cooled to 25°C, 1.2 g of propargyl bromide was added, and the mixture was heated to 62°C and held for 23 h. The mixture was washed with hot water, filtered, and dried, and chloroform and ethanol were added to obtain a polyaryl ether ketone oligomer containing an alkynyl terminal group.

[0078] 2) Mix 80 mL of isopropanol and 2.4 g of epoxy-terminated polydimethylsiloxane, add 15 mL of deionized water and 1.04 g of sodium azide, adjust the pH of the solution to 5, stir at 50°C overnight, adjust the pH of the solution to 7, extract four times with 30 mL of pentane, wash, and dry to obtain azido polydimethylsiloxane;

[0079] 3) Under a nitrogen atmosphere, 0.5 g of a terminal alkyne-containing poly(aryl ether ketone) oligomer, 1.5 g of azidated polydimethylsiloxane, 7.5 mL of N-methylpyrrolidone, and 7.5 mL of tetrahydrofuran were mixed, 0.02 g of copper sulfate and 0.03 g of sodium ascorbate were added, the mixture was heated to 62°C and kept warm for 7 h, poured into ethanol, dried, and extracted in a Soxhlet extractor with acetone as the extractant. The mixture was dried to obtain a hydroxyl-containing poly(aryl ether ketone)-polydimethylsiloxane copolymer.

[0080] The reactive diluent is dipropylene glycol diacrylate;

[0081] S2: mixing dicyclopentadiene-phenol epoxy resin, additives, and pigments, grinding and sieving to obtain a mixed base material B;

[0082] In the mixed base B, the mass ratio of dicyclopentadiene-phenol epoxy resin, additives, and pigment is 10:2:3;

[0083] The additives are dispersant, leveling agent and defoamer mixed in a mass ratio of 1:1:1;

[0084] S3: Put the mixed base material A and the mixed base material B into a high-speed disperser for dispersion treatment to obtain a low-loss circuit board ink; the mass ratio of the mixed base material A to the mixed base material B is 85:15; the working conditions of the dispersion treatment are: temperature 65°C, time 1 hour.

[0085] Comparative Example 1: Taking Example 3 as the control group, polyurethane acrylate (000000380: Wuhan Kanos Technology Co., Ltd.) was used to replace the composite polyurethane acrylate, and the other processes were normal.

[0086] Comparative Example 2: Taking Example 3 as the control group, modified silicon micropowder was replaced by silicon micropowder, and other processes were normal.

[0087] The solvent in the examples and comparative examples was tetrahydrofuran and n-hexane mixed in a mass ratio of 1:1.

[0088] Sources of raw materials used (for demonstration purposes only):

[0089] Silica powder (average particle size 0.39µm, density 2.23g / cm 3, Dk (1MHz) is 3.82, Df (1MHz) is 0.00019): commercially available; photoinitiator (2-hydroxy-2-methylpropiophenone, 99%): Shanghai Tongyuan Chemical Co., Ltd.; hydroxy-terminated polybutadiene 0002: Wuhan Puluofu Biotechnology Co., Ltd.; dicyclopentadiene-phenol epoxy resin HP-7200: Guangzhou Taiji New Materials Co., Ltd.; dispersant CP-88: Linyi Guoli Chemical Co., Ltd.; leveling agent TSF400: Guangzhou Hengyu Chemical Co., Ltd.; defoamer XPJ05: Jinan Shanhai Chemical Technology Co., Ltd.; pigment (green) GA3274: Hubei Guangao Biotechnology Co., Ltd.; p-Hydroxyanisole (industrial grade): Hubei Qifei Pharmaceutical Chemical Co., Ltd.; 4-(4-Hydroxyphenyl)-2,3-diazin-1-one (industrial grade): Dalian Baolimo New Materials Co., Ltd. Company; Epoxy-terminated polydimethylsiloxane 2315: Suzhou Senfida Chemical Co., Ltd.; 3-Aminopropyltriethoxysilane A107147, Succinic anhydride S104823, p-Toluenesulfonic acid T104290, Isophorone diisocyanate I109582, Polymethyl methacrylate P742581, Dibutyltin dilaurate D100274, Hydroxyethyl acrylate H104535 , 4,4'-difluorobenzophenone M106424, propargyl bromide P106961, sodium ascorbate S105024, dipropylene glycol diacrylate D154720: Aladdin reagent; ethyl acetate, isopropyl alcohol, potassium carbonate, toluene, chloroform, N,N-dimethylformamide, ethanol, sodium azide, N-methylpyrrolidone, tetrahydrofuran, copper sulfate pentahydrate, n-hexane, pentane, analytical grade: commercially available.

[0090] Performance testing:

[0091] The inks prepared in the examples and comparative examples were tested: the inks prepared in the examples and comparative examples were coated on a 1.5oz copper plate with a thickness of 60µm, kept at 75°C for 60min, and heated at 500mj / cm 2 Irradiate for 60 seconds to obtain the sample;

[0092] Hydrophobicity: Characterized by water contact angle, tested with a tester using 2µL deionized water as the test liquid; High temperature resistance: Tested using a hot and cold cycle method, the sample was kept at 260°C for 15 seconds, then removed and placed in -10°C for 15 seconds. After 10 high and low temperature cycles, the ink layer was considered qualified if there was no cavitation, peeling, or damage; otherwise, it was considered unqualified; Corrosion resistance: The sample was placed in a 10% sodium chloride aqueous solution and kept at 26°C for 26 hours. The ink layer was considered qualified if there was no cavitation, peeling, or damage; otherwise, it was considered unqualified. The results are shown in Table 1.

[0093] Table 1

[0094]

[0095] The present invention provides a low-loss circuit board ink and a preparation method thereof, and produces a high-reliability solder mask ink with good high-temperature resistance, strong corrosion resistance, and good hydrophobicity. When applied to the surface solder mask process of printed circuit boards such as high-layer and high-density packaging printed circuit boards, arbitrary interconnection boards, and server boards, the ink has the characteristics of high stability and low dielectric loss.

[0096] By comparing Example 3 with Comparative Example 1, it can be seen that in order to further improve the high temperature resistance of the ink, the present invention selects terminal hydroxyl polybutadiene with a flexible long carbon chain structure as a raw material and isophorone diisocyanate to synthesize a prepolymer under the action of a catalyst, and uses hydroxyethyl acrylate and a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer as a capping agent to synthesize a photocurable composite polyurethane acrylate with good mechanical strength, high and low temperature resistance, and hydrophobicity; wherein the hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer uses diazinone biphenyl bisphenol and difluoroketone as raw materials, and is sequentially subjected to nucleophilic condensation and bromopropyne capping to obtain a polyaryletherketone oligomer with an alkynyl group at the end of the molecular chain, and then is prepared by click grafting azidation of polydimethylsiloxane to obtain a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer, thereby greatly improving the high and low temperature resistance and hydrophobicity of the ink.

[0097] By comparing Example 3 with Comparative Example 2, it can be seen that in order to improve the uniformity of dispersion of filler silicon micropowder in the ink, the silicon micropowder is first carboxylated and then modified with a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer to improve the adhesion of the silicon micropowder and prevent the silicon micropowder from falling off under conditions such as external force impact, thereby improving the high temperature resistance, water resistance and corrosion resistance of the ink.

[0098] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structural transformations made using the present invention specification under the inventive concept of the present invention, or any direct / indirect application in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A method for preparing low-loss circuit board ink, characterized in that: The following steps are involved: S1: polymethyl methacrylate, composite polyurethane acrylate, reactive diluent, modified silica powder, photoinitiator, and solvent are stirred and mixed, and then ground and sieved to obtain a mixed base material A; S2: mixing dicyclopentadiene-phenol epoxy resin, additives, and pigments, grinding and sieving to obtain a mixed base material B; S3: putting the mixed base material A and the mixed base material B into a high-speed disperser for dispersion treatment to obtain a low-loss circuit board ink; The preparation of the composite polyurethane acrylate comprises the following steps: Under a nitrogen atmosphere, heat the hydroxy-terminated polybutadiene in an oil bath at 105°C for 2 hours, cool to 18-25°C, add ethyl acetate, add a mixture of isophorone diisocyanate and ethyl acetate, add dibutyltin dilaurate and p-hydroxyanisole, and heat in an oil bath at 38-42°C for 30-40 minutes, add a mixture of hydroxyethyl acrylate, a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer, and ethyl acetate, add dibutyltin dilaurate and p-hydroxyanisole, and heat to 68-72°C and heat for 1-2 hours to obtain a composite polyurethane acrylate; The preparation of the modified silicon micropowder comprises the following steps: (1) 3-aminopropyltriethoxysilane, succinic anhydride, and N,N-dimethylformamide were mixed and stirred for 2-3 hours, and the temperature was raised to 50-60°C. A mixture of silicon micropowder and N,N-dimethylformamide was added, and deionized water was added. The mixture was stirred for 4-5 hours, centrifuged, washed with alcohol, and dried to obtain carboxylated silicon micropowder. (2) Under a nitrogen atmosphere, a hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer, carboxylated silicon micropowder, p-toluenesulfonic acid, and N,N-dimethylformamide are mixed, kept at 140-145°C for 4-5 hours, cooled, filtered, washed, and dried to obtain modified silicon micropowder; The preparation of the hydroxyl-containing polyaryletherketone-polydimethylsiloxane copolymer comprises the following steps: 1) Under a nitrogen atmosphere, 4-(4-hydroxyphenyl)-2,3-naphthyridin-1-one, 4,4'-difluorobenzophenone, potassium carbonate, N-methylpyrrolidone, and toluene were mixed, heated to 148-152°C and kept for 1 hour, then heated to 178-182°C and kept for 2-3 hours, cooled to 18-25°C, and propargyl bromide was added. The mixture was heated to 58-62°C and kept for 23-24 hours. The mixture was washed with hot water, filtered, and dried. Chloroform and ethanol were added to obtain a polyaryl ether ketone oligomer containing an alkynyl terminal group. 2) Mix isopropyl alcohol and epoxy-terminated polydimethylsiloxane, add deionized water and sodium azide, adjust the pH of the solution to 5, stir at 45-50°C overnight, adjust the pH of the solution to 7, extract with pentane 3-4 times, wash, and dry to obtain azido polydimethylsiloxane; 3) Under a nitrogen atmosphere, a poly(aryl ether ketone) oligomer containing an alkynyl terminal group, polydimethylsiloxane azide, N-methylpyrrolidone, and tetrahydrofuran are mixed, copper sulfate and sodium ascorbate are added, the mixture is heated to 58-62°C and kept warm for 7-8 hours, poured into ethanol, dried, and extracted in a Soxhlet extractor with acetone as the extractant. The mixture is dried to obtain a hydroxyl-containing poly(aryl ether ketone)-polydimethylsiloxane copolymer.

2. The method for preparing a low-loss circuit board ink according to claim 1, characterized in that: The working conditions of the dispersion treatment are: temperature 55-65℃, time 1-2h.

3. The method for preparing a low-loss circuit board ink according to claim 1, characterized in that: The additive is a dispersant, a leveling agent, and a defoaming agent mixed in a mass ratio of 1:1:

1.

4. The method for preparing a low-loss circuit board ink according to claim 1, characterized in that: The active diluent is one or a combination of ditrimethylolpropane acrylate, dipropylene glycol diacrylate, and propane trimethanol triacrylate.

5. The method for preparing a low-loss circuit board ink according to claim 1, characterized in that: The mass ratio of the mixed base material A to the mixed base material B is 85:

15.

6. The method for preparing a low-loss circuit board ink according to claim 1, characterized in that: In parts by weight, the raw material composition of the mixed base material A is: 11-16 parts of polymethyl methacrylate, 22-42 parts of composite polyurethane acrylate, 1-3 parts of reactive diluent, 1-3 parts of photoinitiator, 4-9 parts of modified silica powder, and 10-20 parts of solvent; in the mixed base material B, the mass ratio of dicyclopentadiene-phenol epoxy resin, additives, and pigment is 10:2:

3.

7. A low-loss circuit board ink, characterized in that: The method is prepared according to any one of claims 1 to 6.

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