A solder resist ink based on tetramethyl biphenyl epoxy resin and preparation method thereof

Abstract

The present invention relates to a solder mask ink based on tetramethyl biphenyl epoxy resin and a preparation method thereof, comprising component A and component B; the component A comprises: 20-50 parts of active monomers, 10-20 parts of acrylic resins, 1-10 parts of modified polyacrylates, 10-30 parts of hexagonal boron nitride, 1-10 parts of silane coupling agents, 1-10 parts of photoinitiators, and 1-10 parts of auxiliary agents; the component B comprises: 20-40 parts of tetramethyl biphenyl epoxy resins, wherein the modified polyacrylate is obtained by reacting alkylphenol polyoxyethylene ether with acrylic acid. The present invention adopts tetramethyl biphenyl epoxy resin, modified polyacrylate, acrylic resin and other components to effectively improve the stability of ink, improve the properties such as adhesion, and overcome the defects in the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of solder resist ink, and in particular to a solder resist ink based on tetramethyl biphenol epoxy resin and a preparation method thereof. Background Art

[0002] Solder mask ink is one of the widely used materials in the electronics manufacturing industry and is an indispensable part of PCB boards. The main function of solder mask ink is to provide permanent protection for PCB boards to prevent problems such as circuit oxidation, corrosion, and short circuits, thereby maintaining the stable operation of the circuit board. Conventional solder mask ink is composed of resin, photoinitiator, color powder, filler, additives, etc., and is processed and applied using screen printing technology.

[0003] With the rapid development of science and technology, the performance of electronic products has developed rapidly, and the precision of electronic components has become higher and higher. Traditional solder mask ink products have exposed many problems and it is difficult to achieve the ideal protection effect, such as:

[0004] There are surface defects, such as bubbles and cracks, which not only affect the appearance of the product and reduce the protective effect, but also interfere with subsequent processing; the adhesion effect is poor, resulting in insufficient adhesion, affecting the accuracy and stability of the PCB board; and the chemical resistance is weak. After contact with solvents and other chemicals, it is easy to be corroded, resulting in exposure and damage of the circuit.

[0005] In summary, existing solder mask ink products can no longer meet current technical requirements, and there is an urgent need to develop a new technical solution to address the deficiencies in existing technologies and meet market and industry needs. Summary of the invention

[0006] Based on this, the present invention provides a solder mask ink based on tetramethyl biphenol epoxy resin and a preparation method thereof. The present invention adopts tetramethyl biphenol epoxy resin, modified polyacrylate, acrylic resin and other components to effectively improve the stability of the ink, improve the properties such as adhesion, and overcome the defects in the prior art.

[0007] An object of the present invention is to provide a solder resist ink based on tetramethyl biphenol epoxy resin, wherein the solder resist ink based on tetramethyl biphenol epoxy resin comprises component A and component B;

[0008] The A component includes the following components in parts by mass:

[0009]

[0010]

[0011] The B component includes the following components in parts by mass:

[0012] 20-40 parts of tetramethyl biphenyl epoxy resin

[0013] 10-30 parts of solvent;

[0014] in,

[0015] The modified polyacrylate is obtained by the reaction of alkylphenol polyoxyethylene ether and acrylic acid.

[0016] Furthermore, the active monomer is a monomer having a monofunctional or multifunctional acrylate unit.

[0017] Furthermore, the polyester acrylic resin is a carboxyl-containing polyester acrylic resin.

[0018] Furthermore, the carboxyl-containing polyester acrylic resin is selected from one or more of a copolymer of maleic anhydride and hydroxyethyl acrylate, a copolymer of epoxy acrylate and anhydride, and a carboxyl polyurethane acrylate.

[0019] Furthermore, the acid value of the carboxyl-containing polyester acrylic resin is 200 mgKOH / g.

[0020] Furthermore, the silane coupling agent is an epoxy silane coupling agent.

[0021] Furthermore, the auxiliary agent is selected from one or more of color powder, leveling agent, defoaming agent, ultraviolet absorber, dispersant, antioxidant and toughening agent.

[0022] Another object of the present invention is to provide a method for preparing the above-mentioned solder mask ink based on tetramethyl biphenol epoxy resin, the method for preparing the solder mask ink based on tetramethyl biphenol epoxy resin comprising the following steps:

[0023] S1, mixing alkylphenol polyoxyethylene ether with acrylic acid, adding a catalyst and an inhibitor, and heating the mixture for reaction to obtain an intermediate product;

[0024] S2, mixing the intermediate product and an initiator, and heating the mixture to react to obtain a modified polyacrylate;

[0025] S3. Mix hexagonal boron nitride and silane coupling agent, heat to react, and then mix with the modified polyacrylate, active monomer, acrylic resin, photoinitiator, auxiliary agent, and solvent to obtain component A; mix tetramethyl biphenol epoxy resin and solvent to obtain component B, mix the components A and B, stir evenly, grind, and filter to obtain a product.

[0026] Furthermore, in step S1, the heating reaction temperature is 80-100°C and the time is 4-8h.

[0027] Furthermore, in step S1, the mass ratio of the alkylphenol polyoxyethylene ether to acrylic acid is (5-10):1.

[0028] Furthermore, in step S2, the heating reaction temperature is 60-100°C and the time is 3-6h.

[0029] Furthermore, in step S3, the heating reaction temperature is 30-60° C. and the time is 10-20 hours.

[0030] The present invention has the following beneficial effects:

[0031] The solder resist ink provided by the present invention adopts tetramethyl biphenyl epoxy resin, modified polyacrylate, carboxyl-containing polyester acrylic resin and other ingredients as raw materials, wherein the modified polyacrylate first adopts acrylic acid and alkylphenol polyoxyethylene ether to react to obtain an intermediate product with double bonds, and then the intermediate product is further polymerized to obtain the modified polyacrylate, the polymer uses alkylphenol polyoxyethylene ether as a branch chain, which can not only promote the emulsification effect and stability of the composition, but also has good compatibility with tetramethyl biphenyl epoxy resin, the introduced benzene ring structure is conducive to the improvement of ink stability and hardness, and a large number of ethoxy groups and long alkyl chain segments can also form intermolecular forces and entangled network structures with the carboxyl-containing polyester acrylic resin, thereby improving the strength of the product.

[0032] The present invention also uses an epoxy silane coupling agent to perform surface treatment on hexagonal boron nitride, thereby improving the dispersibility of the filler, and the introduced epoxy group can be chemically cross-linked with tetramethyl biphenol epoxy resin, carboxyl-containing polyester acrylic resin and monomers with multiple functional groups. Under the emulsification and dispersion effect of the modified polyacrylate, it can be more uniformly and stably embedded in the network structure of the polymer, play a filling and reinforcing role, and further promote the improvement of the stability and mechanical properties of the solder mask ink. DETAILED DESCRIPTION

[0033] In order to more clearly illustrate the technical solution of the present invention, the following examples are listed. Unless otherwise stated, the raw materials, reactions and post-treatment methods shown in the examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0034] The words "preferred", "preferably", "more preferably", etc. in the present invention refer to embodiments of the present invention that can provide certain beneficial effects in certain circumstances. However, other embodiments may also be preferred under the same circumstances or other circumstances. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not applicable, nor is it intended to exclude other embodiments from the scope of the present invention.

[0035] It should be understood that, except in any operating examples, or where otherwise indicated, all numbers indicating, for example, the amounts of ingredients used in the specification and claims should be understood to be modified in all cases by the term "about". Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and the appended claims are approximate values ​​that vary depending on the desired properties to be obtained by the present invention.

[0036] The active monomers in the embodiment of the present invention are trimethylolpropane triacrylate (TMPTA) and polydipentaerythritol hexaacrylate (DPHA) in a mass ratio of 1:1.

[0037] The tetramethyl biphenol epoxy resin in the embodiment of the present invention was purchased from Suzhou Senfeida Chemical Co., Ltd., and has a melting point of about 105°C.

[0038] The acrylic resin in the embodiment of the present invention is a copolymer of acrylic ester and anhydride, the brand is Sartomer SB520A20, and the acid value is 200 mgKOH / g (content 80%).

[0039] The photoinitiators in the embodiments of the present invention are ITX and 819.

[0040] The auxiliary agent in the embodiment of the present invention is a leveling agent and a dispersant in a mass ratio of 1:1, the leveling agent is isopropanol, and the dispersant is sodium dodecyl sulfate.

[0041] The solvent in the embodiment of the present invention is dibasic acid ester (DBE).

[0042] The alkylphenol polyoxyethylene ether in the embodiment of the present invention is nonylphenol polyoxyethylene ether NP-10.

[0043] The hexagonal boron nitride in the embodiment of the present invention is subjected to surface hydroxylation treatment, which comprises the following steps:

[0044] The hexagonal boron nitride was immersed in a 5 mol / L sodium hydroxide solution, ultrasonically treated for 6 hours, then placed in a high-pressure reactor at 180° C. for reaction for 24 hours, and the product was obtained after washing and drying.

[0045] The "parts" in the embodiments of the present invention refer to parts by mass.

[0046] Example 1

[0047] A solder resist ink based on tetramethyl biphenol epoxy resin, comprising component A and component B;

[0048] The A component includes the following components in parts by mass:

[0049]

[0050] The B component includes the following components in parts by mass:

[0051] 20 parts of tetramethyl biphenyl epoxy resin

[0052] 10 parts of solvent;

[0053] The method for preparing the solder mask ink based on tetramethyl biphenol epoxy resin comprises the following steps:

[0054] S1, mixing alkylphenol polyoxyethylene ether and acrylic acid in a mass ratio of 5:1, adding 3wt% of p-toluenesulfonic acid and 0.06wt% of hydroquinone, reacting at 90°C for 6h under a vacuum degree of 0.03MPa, and then removing excess acrylic acid by reduced pressure distillation to obtain an intermediate product;

[0055] S2, adding the intermediate product in a mass ratio of 1:2 into water, adding ammonium persulfate (2 wt% of the intermediate product) at 60° C. with stirring, reacting at 85° C. for 3 h, cooling and standing, separating the lower layer of liquid, and obtaining modified polyacrylate;

[0056] S3. Mix ethanol and water in a volume ratio of 4:5, add hexagonal boron nitride and KH560 according to the above mass fractions, stir and react at 70°C for 24 hours, filter, wash and dry, mix the solid product with the modified polyacrylate, active monomer, acrylic resin, photoinitiator, auxiliary agent and solvent to obtain component A; mix tetramethyl biphenol epoxy resin and solvent to obtain component B, mix the components A and B, stir and disperse them evenly, and grind them to a fineness of less than 1 μm to obtain a product.

[0057] Example 2

[0058] A solder resist ink based on tetramethyl biphenol epoxy resin, comprising component A and component B;

[0059] The A component includes the following components in parts by mass:

[0060]

[0061] The B component includes the following components in parts by mass:

[0062] 40 parts of tetramethyl biphenyl epoxy resin

[0063] 30 parts of solvent;

[0064] The method for preparing the solder mask ink based on tetramethyl biphenol epoxy resin comprises the following steps:

[0065] S1, mixing alkylphenol polyoxyethylene ether and acrylic acid in a mass ratio of 5:1, adding 3wt% of p-toluenesulfonic acid and 0.06wt% of hydroquinone, reacting at 90°C for 6h under a vacuum degree of 0.03MPa, and then removing excess acrylic acid by reduced pressure distillation to obtain an intermediate product;

[0066] S2, adding the intermediate product in a mass ratio of 1:2 into water, adding ammonium persulfate (2 wt% of the intermediate product) at 60° C. with stirring, reacting at 85° C. for 3 h, cooling and standing, separating the lower layer of liquid, and obtaining modified polyacrylate;

[0067] S3. Mix ethanol and water in a volume ratio of 4:5, add hexagonal boron nitride and KH560 according to the above mass fractions, stir and react at 70°C for 24 hours, filter, wash and dry, mix the solid product with the modified polyacrylate, active monomer, acrylic resin, photoinitiator, auxiliary agent and solvent to obtain component A; mix tetramethyl biphenol epoxy resin and solvent to obtain component B, mix the components A and B, stir and disperse them evenly, and grind them to a fineness of less than 1 μm to obtain a product.

[0068] Example 3

[0069] A solder resist ink based on tetramethyl biphenol epoxy resin, comprising component A and component B;

[0070] The A component includes the following components in parts by mass:

[0071]

[0072]

[0073] The B component includes the following components in parts by mass:

[0074] 30 parts of tetramethyl biphenyl epoxy resin

[0075] 20 parts of solvent;

[0076] The method for preparing the solder mask ink based on tetramethyl biphenol epoxy resin comprises the following steps:

[0077] S1, mixing alkylphenol polyoxyethylene ether and acrylic acid in a mass ratio of 5:1, adding 3wt% of p-toluenesulfonic acid and 0.06wt% of hydroquinone, reacting at 90°C for 6h under a vacuum degree of 0.03MPa, and then removing excess acrylic acid by reduced pressure distillation to obtain an intermediate product;

[0078] S2, adding the intermediate product in a mass ratio of 1:2 into water, adding ammonium persulfate (2 wt% of the intermediate product) at 60° C. with stirring, reacting at 85° C. for 3 h, cooling and standing, separating the lower layer of liquid, and obtaining modified polyacrylate;

[0079] S3. Mix ethanol and water in a volume ratio of 4:5, add hexagonal boron nitride and KH560 according to the above mass fractions, stir and react at 70°C for 24 hours, filter, wash and dry, mix the solid product with the modified polyacrylate, active monomer, acrylic resin, photoinitiator, auxiliary agent and solvent to obtain component A; mix tetramethyl biphenol epoxy resin and solvent to obtain component B, mix the components A and B, stir and disperse them evenly, and grind them to a fineness of less than 1 μm to obtain a product.

[0080] Comparative Example 1

[0081] A solder resist ink. The difference between this comparative example and Example 1 is that steps S1 and S2 are omitted, and the modified polyacrylate is replaced by nonylphenol polyoxyethylene ether. Other ingredients and preparation methods are the same as those in Example 1.

[0082] Comparative Example 2

[0083] A solder resist ink. The difference between this comparative example and Example 1 is that the mass of tetramethyl biphenyl epoxy resin is replaced by bisphenol A epoxy resin (E44), and the other ingredients and preparation method are the same as those in Example 1.

[0084] Comparative Example 3

[0085] A solder resist ink. The difference between this comparative example and Example 1 is that in step S3, hexagonal boron nitride, KH560 and other components are directly mixed, and other components and preparation methods are the same as those in Example 1.

[0086] Test Case

[0087] The performance tests were performed on the solder mask inks prepared in Examples 1-3 and Comparative Examples 1-3.

[0088] The test method is as follows:

[0089] The solder resist inks prepared in the examples and comparative examples were applied to the PCB boards respectively and photocured for 1 h (wavelength 395 nm, intensity 25.0 mW / cm 2 UV light), and then thermally cured at 150°C for 1h to form a 0.5mm thick film.

[0090] Pencil hardness: measured in accordance with JIS K5400.

[0091] Adhesion: Use a needle tip to make an "X" on the film, then stick a cellophane tape on the cut and pull it. The evaluation criteria are as follows:

[0092] ○: not torn off or only a small amount torn off;

[0093] ×: A large amount of tearing occurs.

[0094] Bending resistance: With the solder mask film as the outer side, bend 180°. The evaluation criteria are as follows:

[0095] ○: No cracks on the film;

[0096] ×: There are cracks on the film.

[0097] Acid resistance / alkali resistance: At 20°C, immerse the PCB coated with ink in a 10% sulfuric acid solution or a 10% sodium hydroxide solution, take it out after 30 minutes, and evaluate the state and adhesion of the coating. The evaluation criteria are as follows:

[0098] ○: no change or slight change was found;

[0099] ×: The coating film is swollen or flaked.

[0100] Heat resistance: Thermal shock performance test is carried out according to the method in IPC-SM-840E, and the evaluation criteria are as follows:

[0101] ○: No bubbles or cracks;

[0102] ×: Bubbles and cracks were present.

[0103] The test results are shown in Table 1.

[0104] Table 1 Performance test results

[0105] project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Pencil hardness 3H 3H 3H 2H 2H 3H Adhesion ○ ○ ○ × ○ × Bending resistance ○ ○ ○ × × × Acid resistance ○ ○ ○ ○ ○ ○ Alkali resistance ○ ○ ○ ○ ○ ○ Heat resistance ○ ○ ○ × × ×

[0106] According to Table 1, it can be concluded that the solder mask ink based on tetramethyl biphenol epoxy resin prepared in the embodiment of the present invention has excellent mechanical properties and stability; Comparative Examples 1 and 2 replaced the modified polyacrylate and tetramethyl biphenol epoxy resin, resulting in a significant decrease in the stability and mechanical strength of the solder mask ink, while Comparative Example 3 directly mixed the silane coupling agent, hexagonal boron nitride and other ingredients, and the coupling agent did not sufficiently modify the surface of the boron nitride, resulting in reduced compatibility between the components, uneven dispersion of the filler, and decreased ink performance. In summary, the solder mask ink based on tetramethyl biphenol epoxy resin of the present invention overcomes the defects existing in the prior art and has good application prospects.

[0107] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0108] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A solder resist ink based on tetramethyl biphenol epoxy resin, characterized in that: The solder mask ink based on tetramethyl biphenol epoxy resin comprises component A and component B; The A component includes the following components in parts by mass: Active monomer 10-30 parts Acrylic resin 10-20 parts Modified polyacrylate 1-10 parts Hexagonal boron nitride 10-30 parts Silane coupling agent 1-10 parts Photoinitiator 1-10 parts 1-10 parts of additives 10-30 parts of solvent; The B component includes the following components in parts by mass: 20-40 parts of tetramethyl biphenyl epoxy resin 10-30 parts of solvent; in, The active monomer is a monomer having a monofunctional or multifunctional acrylate unit; The silane coupling agent is an epoxy silane coupling agent; The method for preparing the solder mask ink based on tetramethyl biphenol epoxy resin comprises the following steps: S1, mixing alkylphenol polyoxyethylene ether with acrylic acid, adding a catalyst and an inhibitor, and heating the mixture for reaction to obtain an intermediate product; S2, mixing the intermediate product and an initiator, and heating the mixture to react to obtain a modified polyacrylate; S3. Mix hexagonal boron nitride and silane coupling agent, heat to react, and then mix with the modified polyacrylate, active monomer, acrylic resin, photoinitiator, auxiliary agent, and solvent to obtain component A; mix tetramethyl biphenol epoxy resin and solvent to obtain component B, mix the components A and B, stir evenly, grind, and filter to obtain a product.

2. The solder resist ink based on tetramethyl biphenol epoxy resin according to claim 1, characterized in that: The acrylic resin is a carboxyl-containing polyester acrylic resin.

3. The solder resist ink based on tetramethyl biphenol epoxy resin according to claim 1, characterized in that: The auxiliary agent is selected from one or more of color powder, leveling agent, defoamer, ultraviolet absorber, dispersant, antioxidant and toughening agent.

4. The solder resist ink based on tetramethyl biphenol epoxy resin according to claim 1, characterized in that: In step S1, the heating reaction temperature is 80-100°C and the time is 4-8 hours.

5. The solder resist ink based on tetramethyl biphenol epoxy resin according to claim 1, characterized in that: In step S1, the mass ratio of the alkylphenol polyoxyethylene ether to acrylic acid is (5-10):

1.

6. The solder resist ink based on tetramethyl biphenol epoxy resin according to claim 1, characterized in that: In step S2, the heating reaction temperature is 60-100°C and the time is 3-6 h.

7. The solder resist ink based on tetramethyl biphenol epoxy resin according to claim 1, characterized in that: In step S3, the heating reaction temperature is 30-60° C. and the time is 10-20 h.

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