A line ink based on alkali-soluble crosslinked acrylic resin and a method for preparing the same

Abstract

This invention discloses a circuit ink based on an alkali-soluble crosslinked acrylic resin. The circuit ink comprises the following components in parts by weight: 10-20 parts alkali-soluble crosslinked acrylic resin, 5-10 parts epoxy acrylic resin, 10-25 parts modified boron nitride, 10-30 parts reactive monomer, 1-3 parts photoinitiator, 1-5 parts additives, and 15-40 parts solvent. The modified boron nitride is a reaction product of boron nitride with a silane coupling agent, a polyol, and phthalic anhydride. The different components of this invention exhibit good compatibility, forming a stable crosslinked structure, ensuring the durability, toughness, strength, and other properties of the ink layer, overcoming the shortcomings of existing technologies, and showing promising application prospects.

Description

Technical Field

[0001] This invention relates to the field of circuit inks, specifically to a circuit ink based on an alkali-soluble crosslinked acrylic resin and its preparation method. Background Technology

[0002] The electronics and information industry is currently experiencing rapid development. Circuit boards, as core components of various electronic devices, directly determine the overall performance and reliability of these devices through the precision of their manufacturing processes and the quality of their materials. Circuit ink is an indispensable material in the circuit board production process, undertaking crucial tasks such as circuit pattern construction and protection. Therefore, researching its performance has significant practical value.

[0003] As electronic products continue to develop towards miniaturization, lightweighting, and high performance, the industry has put forward more stringent standards for the accuracy and reliability of circuit boards. However, traditional circuit inks have gradually shown their limitations in many aspects.

[0004] On the one hand, some inks have poor chemical corrosion resistance. In subsequent circuit board processing steps, such as etching and electroplating, they are easily corroded by chemical reagents, leading to blurred or even damaged circuit patterns and severely impacting the yield rate. For example, in acidic etching processes, some inks cannot effectively prevent acid penetration, resulting in over-etching of circuit edges and ultimately reducing circuit precision. On the other hand, ink adhesion has long plagued the industry's development. When circuit boards are in complex environments such as high temperature, high humidity, or frequent bending, insufficient adhesion between the ink and the substrate can easily lead to peeling and detachment. This can further cause serious malfunctions such as electrical short circuits, shortening the lifespan of electronic products and reducing their safety.

[0005] Choosing suitable inorganic fillers can improve the stability, lubricity, and insulation of circuit inks, which is beneficial for meeting the specific functional requirements of inks. However, the large differences in polarity and density between inorganic fillers and matrix resins make them prone to agglomeration and sedimentation in ink mixing systems, which further affects the adhesion, precision, and strength of inks, posing challenges to subsequent processing techniques.

[0006] In conclusion, there is an urgent need to develop a new technical solution to address the problems existing in the current technology. Summary of the Invention

[0007] This invention provides a circuit ink based on alkali-soluble cross-linked acrylic resin and its preparation method. The circuit ink based on alkali-soluble cross-linked acrylic resin is composed of multiple components such as alkali-soluble cross-linked acrylic resin and modified boron nitride. The different components have good compatibility and can form a stable cross-linked structure, which ensures the durability, toughness, strength and other properties of the ink layer. It overcomes the shortcomings of the prior art and has good application prospects.

[0008] One object of the present invention is to provide a circuit ink based on an alkali-soluble crosslinked acrylic resin, wherein the circuit ink based on the alkali-soluble crosslinked acrylic resin comprises the following components in parts by weight:

[0009] 10-20 parts of alkali-soluble cross-linked acrylic resin

[0010] 5-10 parts of epoxy acrylic resin

[0011] 10-25 parts of modified boron nitride

[0012] 10-30 parts of active monomer

[0013] 1-3 parts of photoinitiator

[0014] 1-5 parts of auxiliary agent

[0015] Solvent 15-40 parts;

[0016] in,

[0017] The modified boron nitride is the product of the reaction of boron nitride with a silane coupling agent, a polyol, and phthalic anhydride.

[0018] Furthermore, the alkali-soluble cross-linked acrylic resin is obtained by reacting styrene, acrylate, acrylic acid, and a cross-linking agent.

[0019] Further, the mass ratio of styrene, acrylate, acrylic acid, and crosslinking agent is (1-3):(3-6):(1-2):(0.1-1).

[0020] Furthermore, the alkyl acrylate includes methyl acrylate and glycidyl acrylate.

[0021] Furthermore, the crosslinking agent is pentaerythritol triacrylate.

[0022] Furthermore, the silane coupling agent is an aminosilane coupling agent.

[0023] Furthermore, the polyol includes glycerol and neopentyl glycol.

[0024] Furthermore, the additives include one or more of pigments, leveling agents, defoamers, toughening agents, dispersants, and ultraviolet absorbers.

[0025] Furthermore, the active monomer is an acrylate having a monofunctional or polyfunctional group.

[0026] Another object of the present invention is to provide a method for preparing the above-mentioned circuit ink based on alkali-soluble crosslinked acrylic resin, wherein the method for preparing the circuit ink based on alkali-soluble crosslinked acrylic resin includes the following steps:

[0027] S1. Styrene, acrylate, acrylic acid, crosslinking agent, and emulsifier are mixed and stirred evenly. Then, an initiator is added, and the mixture is heated under an inert gas atmosphere to obtain an alkali-soluble crosslinked acrylic resin.

[0028] S2. Boron nitride is hydroxylated, then mixed with a silane coupling agent and heated to react, yielding an intermediate product.

[0029] S3. The intermediate product, polyol and phthalic anhydride are mixed and heated to react, thereby obtaining modified boron nitride.

[0030] S4. Mix the alkali-soluble cross-linked acrylic resin, epoxy acrylic resin, modified boron nitride, active monomer, photoinitiator, additives and solvent, stir evenly, and grind to obtain the circuit ink based on the alkali-soluble cross-linked acrylic resin.

[0031] Furthermore, in step S1, the temperature of the heating reaction is 60-100℃.

[0032] Furthermore, in step S3, the temperature of the heating reaction is 100-130°C.

[0033] Furthermore, the mass ratio of the intermediate product, phthalic anhydride, glycerol, and neopentyl glycol is (1-2):(2-3):1:(0.2-0.5).

[0034] The present invention has the following beneficial effects:

[0035] This invention provides a circuit ink based on alkali-soluble crosslinked acrylic resin, the main components of which include alkali-soluble crosslinked acrylate, epoxy acrylic resin, and modified boron nitride. The alkali-soluble crosslinked acrylate uses styrene, alkyl acrylate, and glycidyl acrylate as polymerizing monomers, and pentaerythritol triacrylate with multiple functional groups as a crosslinking agent. The copolymerized product has a three-dimensional, dense network structure, which can improve the stability and strength of the ink. The modified boron nitride is first treated with a silane coupling agent to introduce amino groups, and then reacted with phthalic anhydride, glycerol, and neopentyl glycol to introduce branched segments and a large number of active hydroxyl groups onto the surface of the boron nitride. The modified boron nitride possesses multiple groups such as benzene rings, ester groups, and ether bonds, improving its compatibility with the matrix resin, enabling more uniform dispersion and preventing agglomeration. Furthermore, the active hydroxyl groups can chemically crosslink with alkali-soluble crosslinked acrylic resins and epoxy acrylic resins, and can also form a synergistic effect through intermolecular forces, greatly improving the bonding strength between different components. Under the action of the multiple crosslinking structure, the overall performance of the product is effectively enhanced. In summary, the circuit ink based on alkali-soluble crosslinked acrylic resin of this invention solves the shortcomings of existing technologies and provides a new approach for the development of circuit inks. Detailed Implementation

[0036] To more clearly illustrate the technical solution of the present invention, the following embodiments are provided. Unless otherwise stated, the raw materials, reactions, and post-processing methods appearing in the embodiments are all commercially available raw materials and technical methods well known to those skilled in the art.

[0037] The terms "preferred," "more preferably," and "more suitable" used in this invention refer to embodiments of the invention that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this invention.

[0038] It should be understood that, except in any operational instance or otherwise indicated, the amounts or all figures representing ingredients used, for example, in the specification and claims, should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise stated, the numerical parameters set forth in the following specification and appended claims are approximate values ​​varying according to the desired performance to be obtained according to the invention.

[0039] The epoxy acrylate resin used in this embodiment of the invention is Sartoma CN104 NS.

[0040] In the embodiments of the present invention, the active monomers are methyl acrylate and butyl acrylate in a mass ratio of 1:1.

[0041] The photoinitiator in this embodiment of the invention is ITX and UVI-6976 in a mass ratio of 1:1.

[0042] In the embodiments of the present invention, the additives are pigment (titanium dioxide) and leveling agent (isopropanol) in a mass ratio of 4:1.

[0043] The solvent used in the embodiments of the present invention is a divalent ester.

[0044] In this embodiment of the invention, the emulsifier is OP-10, purchased from Aladdin; the initiator is potassium persulfate.

[0045] In the embodiments of this invention, "parts" refers to parts by mass.

[0046] Example 1

[0047] A circuit ink based on an alkali-soluble crosslinked acrylic resin, wherein the circuit ink based on the alkali-soluble crosslinked acrylic resin comprises the following components in parts by weight:

[0048] 10 parts of alkali-soluble cross-linked acrylic resin

[0049] 5 parts epoxy acrylic resin

[0050] 15 parts of modified boron nitride

[0051] 15 parts of active monomer

[0052] 1 part photoinitiator

[0053] 2 portions of auxiliary agent

[0054] 15 parts solvent.

[0055] The above-mentioned method for preparing circuit ink based on alkali-soluble crosslinking acrylic resin includes the following steps:

[0056] S1. Using water as a solvent, styrene, methyl methacrylate, glycidyl methacrylate, acrylic acid, pentaerythritol triacrylate, and emulsifier were mixed and stirred evenly in a mass ratio of 1:3.5:0.5:3:0.2:0.2. Then, an initiator (10 wt% of the emulsifier) ​​was added, and the mixture was reacted at 80°C for 6 h under a nitrogen atmosphere. After cooling, the solvent was removed to obtain an alkali-soluble crosslinked acrylic resin.

[0057] S2. Boron nitride was immersed in a 5 mol / L NaOH solution and refluxed at 120°C for 12 h. After washing and drying, hydroxylated boron nitride was obtained.

[0058] Using a mixture of ethanol and water in a mass ratio of 95:5 as a solvent, the hydroxylated boron nitride and KH-550 in a mass ratio of 1:1 were added, and the mixture was reacted at 60°C for 6 h. After washing and drying, the intermediate product was obtained.

[0059] S3. Phthalic anhydride, glycerol and neopentyl glycol are mixed evenly, heated to 180°C and reacted for 4 h. After cooling to 120°C, the intermediate product is added and the reaction is continued for 4 h. After washing and drying, modified boron nitride is obtained.

[0060] The mass ratio of the intermediate product, phthalic anhydride, glycerol, and neopentyl glycol is 1.5:2.5:1:0.4.

[0061] S4. According to the above-mentioned mass proportions, mix the alkali-soluble cross-linked acrylic resin, epoxy acrylic resin, modified boron nitride, active monomer, photoinitiator, additives, and solvent, stir evenly, and grind to a fineness ≤20 μm to obtain the circuit ink based on the alkali-soluble cross-linked acrylic resin.

[0062] Example 2

[0063] A circuit ink based on an alkali-soluble crosslinked acrylic resin, wherein the circuit ink based on the alkali-soluble crosslinked acrylic resin comprises the following components in parts by weight:

[0064] 15 parts of alkali-soluble cross-linked acrylic resin

[0065] 7 parts epoxy acrylic resin

[0066] 20 parts of modified boron nitride

[0067] 20 parts of active monomer

[0068] 1.5 parts of photoinitiator

[0069] 3 parts of auxiliary agent

[0070] Solvent 20 parts.

[0071] The above-mentioned method for preparing circuit ink based on alkali-soluble crosslinking acrylic resin includes the following steps:

[0072] S1. Using water as a solvent, styrene, methyl methacrylate, glycidyl methacrylate, acrylic acid, pentaerythritol triacrylate, and emulsifier were mixed and stirred evenly in a mass ratio of 1:3.5:0.5:3:0.2:0.2. Then, an initiator (10 wt% of the emulsifier) ​​was added, and the mixture was reacted at 80°C for 6 h under a nitrogen atmosphere. After cooling, the solvent was removed to obtain an alkali-soluble crosslinked acrylic resin.

[0073] S2. Boron nitride was immersed in a 5 mol / L NaOH solution and refluxed at 120°C for 12 h. After washing and drying, hydroxylated boron nitride was obtained.

[0074] Using a mixture of ethanol and water in a mass ratio of 95:5 as a solvent, the hydroxylated boron nitride and KH-550 in a mass ratio of 1:1 were added, and the mixture was reacted at 60°C for 6 h. After washing and drying, the intermediate product was obtained.

[0075] S3. Phthalic anhydride, glycerol and neopentyl glycol are mixed evenly, heated to 180°C and reacted for 4 h. After cooling to 120°C, the intermediate product is added and the reaction is continued for 4 h. After washing and drying, modified boron nitride is obtained.

[0076] The mass ratio of the intermediate product, phthalic anhydride, glycerol, and neopentyl glycol is 1.5:2.5:1:0.4.

[0077] S4. According to the above-mentioned mass proportions, mix the alkali-soluble cross-linked acrylic resin, epoxy acrylic resin, modified boron nitride, active monomer, photoinitiator, additives, and solvent, stir evenly, and grind to a fineness ≤20 μm to obtain the circuit ink based on the alkali-soluble cross-linked acrylic resin.

[0078] Example 3

[0079] A circuit ink based on an alkali-soluble crosslinked acrylic resin, wherein the circuit ink based on the alkali-soluble crosslinked acrylic resin comprises the following components in parts by weight:

[0080] 20 parts of alkali-soluble cross-linked acrylic resin

[0081] 9 parts epoxy acrylic resin

[0082] 25 parts of modified boron nitride

[0083] 25 parts of active monomer

[0084] 2 parts of photoinitiator

[0085] 4 parts of auxiliary agent

[0086] 25 parts solvent.

[0087] The above-mentioned method for preparing circuit ink based on alkali-soluble crosslinking acrylic resin includes the following steps:

[0088] S1. Using water as a solvent, styrene, methyl methacrylate, glycidyl methacrylate, acrylic acid, pentaerythritol triacrylate, and emulsifier were mixed and stirred evenly in a mass ratio of 1:3.5:0.5:3:0.2:0.2. Then, an initiator (10 wt% of the emulsifier) ​​was added, and the mixture was reacted at 80°C for 6 h under a nitrogen atmosphere. After cooling, the solvent was removed to obtain an alkali-soluble crosslinked acrylic resin.

[0089] S2. Boron nitride was immersed in a 5 mol / L NaOH solution and refluxed at 120°C for 12 h. After washing and drying, hydroxylated boron nitride was obtained.

[0090] Using a mixture of ethanol and water in a mass ratio of 95:5 as a solvent, the hydroxylated boron nitride and KH-550 in a mass ratio of 1:1 were added, and the mixture was reacted at 60°C for 6 h. After washing and drying, the intermediate product was obtained.

[0091] S3. Phthalic anhydride, glycerol and neopentyl glycol are mixed evenly, heated to 180°C and reacted for 4 h. After cooling to 120°C, the intermediate product is added and the reaction is continued for 4 h. After washing and drying, modified boron nitride is obtained.

[0092] The mass ratio of the intermediate product, phthalic anhydride, glycerol, and neopentyl glycol is 1.5:2.5:1:0.4.

[0093] S4. According to the above-mentioned mass proportions, mix the alkali-soluble cross-linked acrylic resin, epoxy acrylic resin, modified boron nitride, active monomer, photoinitiator, additives, and solvent, stir evenly, and grind to a fineness ≤20 μm to obtain the circuit ink based on the alkali-soluble cross-linked acrylic resin.

[0094] Comparative Example 1

[0095] A circuit ink, the difference between this comparative example and Example 1 is that step S1 is deleted, and the alkali-soluble cross-linked acrylic resin is replaced with epoxy acrylic resin. The dosage of other components and the preparation method are the same as in Example 1.

[0096] Comparative Example 2

[0097] A circuit ink, the difference between this comparative example and Example 1 is that step S3 is modified as follows:

[0098] S3. Mix the intermediate product with polyethylene glycol 400 at a mass ratio of 1:4, heat to 120°C, react for 4 h, and then wash and dry to obtain modified boron nitride.

[0099] The dosage of other ingredients and the preparation method are the same as in Example 1.

[0100] Test case

[0101] The performance of the circuit ink samples prepared in Examples 1-3 and Comparative Examples 1-2 was tested.

[0102] The testing method is as follows:

[0103] The circuit inks prepared in the examples and comparative examples were coated onto PCB boards and cured with light for 1 hour (wavelength 395 nm, intensity 25.0 mW / cm²). 2 (The film is exposed to ultraviolet light), and then heat-cured at 150°C for 1 hour to form a 0.7 mm thick film.

[0104] Adhesion: Use a needle tip to draw an "X" shape on the film, then apply cellophane tape to the marks and pull it. Evaluate according to the following criteria:

[0105] Excellent: Not torn off;

[0106] Medium: Tear off a small amount;

[0107] Poor: A large amount was torn off.

[0108] Bending resistance: The ink film is bent 180° with the outside facing outwards, and then returned to a horizontal position. This bending is repeated 10 times, and the results are evaluated according to the following criteria:

[0109] Pass: No cracks on the film;

[0110] Poor: The film has cracks.

[0111] Water resistance: At 20℃, the PCB board coated with circuit ink was immersed in deionized water for 120 hours. After removal, the coating condition and adhesion were evaluated, and the judgment criteria were as follows:

[0112] Pass: No changes or slight changes were found;

[0113] Poor: The coating film shows swelling or swelling and peeling.

[0114] Acid resistance: At 20°C, a PCB board coated with circuit ink was immersed in a 10% sulfuric acid solution. After 3 hours, it was removed and the state and adhesion of the coating were evaluated. The judgment criteria are as follows:

[0115] Pass: No changes or slight changes were found;

[0116] Poor: The coating film shows swelling or swelling and peeling.

[0117] Heat resistance: Thermal shock performance was tested according to the method in IPC-SM-840E, and the judgment criteria are as follows:

[0118] Pass: No bubbles or cracks;

[0119] Poor: Bubbles and cracks appear.

[0120] Film removal properties: Immerse the sample in 5% sodium hydroxide solution at 50℃ for 5 min. The judgment criteria are as follows:

[0121] Pass: Film completely removed;

[0122] Poor: The film cannot be removed.

[0123] The test results are shown in Table 1.

[0124] Table 1 Performance Test Results

[0125]

[0126] The test results above show that the circuit ink based on alkali-soluble cross-linked acrylic resin prepared in this invention exhibits good hardness, adhesion, flexural strength, and solvent resistance, demonstrating excellent performance and meeting the performance requirements of the electronics industry for PCB circuit inks. However, Example 1, which replaced the alkali-soluble cross-linked acrylic resin, showed a decrease in strength and poor alkali solubility, making it difficult to meet the requirements for film removal. Example 2, which replaced modified boron nitride, affected the network cross-linking structure formed between the components, making it difficult to achieve the ideal synergistic effect, resulting in a decrease in stability, strength, and other properties. In summary, the circuit ink based on alkali-soluble cross-linked acrylic resin of this invention solves the defects existing in the prior art and has good application prospects.

[0127] 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 invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0128] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A circuit ink based on alkali-soluble crosslinked acrylic resin, characterized in that, The ingredients include the following components in parts by weight: 10-20 parts of alkali-soluble cross-linked acrylic resin 5-10 parts of epoxy acrylic resin 10-25 parts of modified boron nitride 10-30 parts of active monomer 1-3 parts of photoinitiator 1-5 parts of auxiliary agent Solvent 15-40 parts; in, The modified boron nitride is the reaction product of boron nitride with a silane coupling agent, a polyol and phthalic anhydride; The alkali-soluble cross-linked acrylic resin is obtained by reacting styrene, methyl methacrylate, glycidyl methacrylate, acrylic acid, and a cross-linking agent. The crosslinking agent is pentaerythritol triacrylate; The silane coupling agent is an aminosilane coupling agent; The polyols include glycerol and neopentyl glycol.

2. The method for preparing circuit ink based on alkali-soluble crosslinked acrylic resin according to claim 1, characterized in that, Includes the following steps: S1. Styrene, methyl methacrylate, glycidyl methacrylate, acrylic acid, crosslinking agent, and emulsifier are mixed and stirred evenly. Then, an initiator is added, and the mixture is heated under an inert gas atmosphere to obtain an alkali-soluble crosslinked acrylic resin. S2. Boron nitride is hydroxylated, then mixed with a silane coupling agent and heated to react, yielding an intermediate product. S3. The intermediate product, polyol and phthalic anhydride are mixed and heated to react, thereby obtaining modified boron nitride. S4. Mix the alkali-soluble cross-linked acrylic resin, epoxy acrylic resin, modified boron nitride, active monomer, photoinitiator, additives and solvent, stir evenly, and grind to obtain the circuit ink based on the alkali-soluble cross-linked acrylic resin.

3. The method for preparing circuit ink based on alkali-soluble crosslinked acrylic resin according to claim 2, characterized in that, In step S1, the temperature of the heating reaction is 60-100℃.

Images