Active hybrid monomer, preparation method thereof, hybrid curing solder resist ink containing the monomer and application thereof

Abstract

The present invention discloses an active hybrid monomer, a preparation method thereof, a hybrid curing solder mask ink containing the monomer, and its application. The invention belongs to the field of solder mask ink technology. The present invention, through the rational proportioning of the components, prepares a free radical-cationic hybrid curing solder mask ink that can rapidly cure under ultraviolet light to form a strong solder mask layer with good mechanical strength and chemical stability, suitable for solder protection of electronic components. The active hybrid monomer of the present invention is prepared from acrylic acid and a hydroxyl- or epoxy-containing oxetane monomer, and has both a free radical-cationic dual curing mechanism, which helps to increase the curing speed of the ink. At the same time, the oxetane group helps to improve the adhesion of the ink, thereby obtaining an excellent solder mask coating.

Description

Technical Field

[0001] The present invention belongs to the technical field of solder resist inks, and in particular relates to an active hybrid monomer, a preparation method thereof, a hybrid curing solder resist ink containing the monomer, and applications thereof. Background Art

[0002] Solder mask inks play a key role in the manufacture of electronic circuit boards. However, existing solder mask inks have certain limitations in terms of curing speed, mechanical strength, and chemical resistance. In recent years, photocurable inkjet solder mask inks have become an important research direction in the field of electronics manufacturing, especially in efficient and precise printing technologies, as they can provide high-quality and efficient solder mask layers for printed circuit boards (PCBs). Free radical-cationic hybrid photocuring systems, as a new type of photopolymerization system, have potential performance advantages, but their application in solder mask inks has not been fully explored. Free radical and cationic initiation systems are generally used, with advantages such as high curing efficiency, low energy consumption, and fast curing. In inkjet printing, photocurable inks can cure rapidly under ultraviolet or visible light irradiation, reducing the evaporation and drying process of traditional wet inks and improving production efficiency.

[0003] Inkjet printing requires inks with low viscosity and good rheological properties to facilitate high-precision printing. However, the resins and photoinitiators in photocurable inks often cause the ink viscosity to be too high, affecting the stability of the inkjet process or clogging the nozzle. CN115851037A discloses a cationic photocurable LED-UV ink with a faster curing speed, but the curing speed is still relatively slow compared to free radical curing. Many studies combine free radical and cationic curing together, which can effectively improve the speed of cationic curing, but the curing speeds of free radical and cationic photocuring are not synchronized, and problems such as poor appearance, hardness and adhesion of the cured film are prone to occur. CN118359962A discloses an inkjet solder mask ink containing ingredients such as carboxyl polyester acrylic resin, modified phenolic resin, cellulose ether, etc., which improves the adhesion, stability and strength of the product, but its photocuring process requires a long time and a high-intensity ultraviolet light source, making it inefficient.

[0004] Therefore, it is of great significance to provide a hybrid curing solder resist ink with low viscosity, fast curing speed and excellent comprehensive performance. Summary of the Invention

[0005] To address the problems of high viscosity, slow curing speed, and severe oxygen inhibition in photocurable solder resist inks, the present invention proposes a reactive hybrid monomer, a preparation method thereof, a hybrid curable solder resist ink containing the monomer, and its application. The hybrid curable solder resist ink of the present invention can be rapidly cured under ultraviolet light conditions to form a solder resist layer with high hardness, good adhesion, and chemical corrosion resistance.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] One of the technical solutions of the present invention:

[0008] An active hybrid monomer, the general structural formula of which is shown in formula (1):

[0009] (1)

[0011] Among them, R1 is a carbon-carbon double bond, R2 is an alkyl chain with 1 to 13 carbon atoms containing an ester group or an alkyl chain with 1 to 13 carbon atoms containing a hydroxyl group and an ester group, and R3 is an alkyl chain with 1 to 4 carbon atoms.

[0012] Furthermore, the active hybrid monomer is selected from the following compounds:

[0013] 、 、 or .

[0014] The C=C double bond in the active hybrid monomer of the present invention can increase the curing speed, and the volume expansion of the cationic ring-opening polymerization of oxetane can compensate for the volume contraction of the free radical polymerization, thereby increasing the curing speed and adhesion of the ink solder mask layer to the substrate.

[0015] The second technical solution of the present invention:

[0016] The present invention also provides a method for preparing the active hybrid monomer, which uses an oxetane-containing compound and an unsaturated acid as raw materials to synthesize an active hybrid monomer having an oxetane-containing terminal group and a carbon-carbon double bond through an esterification reaction.

[0017] Furthermore, the preparation method of the active hybrid monomer comprises the following steps: mixing an oxetane-containing compound and a catalyst, heating the mixture to 85-95° C. while stirring under nitrogen protection, adding a mixture of an unsaturated acid and a polymerization inhibitor, heating the mixture to 100-105° C. for reaction until the acid value is lower than 10 mg NaOH or KOH / g, continuing the reaction for 30 minutes, stopping heating, maintaining stirring and nitrogen conditions, cooling the mixture to 38-42° C. for discharging, and obtaining the active hybrid monomer, which is recorded as an unsaturated acid active hybrid monomer.

[0018] The present invention utilizes acrylic acid to undergo an esterification reaction with an epoxy group or hydroxyl group-containing oxetane to connect a C=C double bond with the oxetane, thereby preparing a reactive hybrid monomer. The reactive hybrid monomer can undergo a photopolymerization reaction under ultraviolet light irradiation to form a cross-linked network, thereby enhancing the curing performance and adhesion of the solder resist ink.

[0019] The general structural formula of the oxetane-containing compound is shown in formula (2):

[0020] (2)

[0022] wherein R4 is a hydroxyl group or an epoxy group, R5 is an alkyl chain having 1 to 9 carbon atoms, and R6 is an alkyl chain having 1 to 4 carbon atoms;

[0023] The general structural formula of the unsaturated acid is shown in formula (3):

[0024] (3)

[0026] Wherein, R is an alkyl chain with 1 to 10 carbon atoms;

[0027] The molar ratio of the oxetane-containing compound to the unsaturated acid is 1:(1-2), preferably 1:1.5.

[0028] Optionally, the oxetane-containing compound is selected from ((3-ethyloxetane-3-yl)methoxy)methanol, 3-ethyl-3-{[(oxiran-2-yl)methoxy]methyl}oxetane (TCM207, ), 3-methyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane, or 3-butyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane.

[0029] Optionally, the unsaturated acid is selected from acrylic acid or 11-dodecenoic acid.

[0030] The catalyst is selected from triphenylphosphine or tetrabutylammonium bromide, preferably triphenylphosphine;

[0031] The polymerization inhibitor is selected from p-hydroxyanisole or hydroquinone, preferably p-hydroxyanisole.

[0032] The third technical solution of the present invention:

[0033] The present invention also provides a hybrid curing solder resist ink, comprising the above-mentioned active hybrid monomer and color paste; wherein the mass ratio of the active hybrid monomer to the color paste is (300-700): (1-1.5).

[0034] Furthermore, the hybrid curable solder resist ink is composed of the following raw materials, calculated by weight: 30-70 parts of reactive hybrid monomer, 40-60 parts of reactive diluent, 3-10 parts of photoinitiator, 1-2 parts of photosensitizer, 0-5 parts of defoamer and 0.1-1.5 parts of color paste.

[0035] Preferably, the hybrid curable solder resist ink is composed of the following raw materials, calculated by weight: 40-60 parts of reactive hybrid monomer, 40-60 parts of reactive diluent, 3-10 parts of photoinitiator, 1-2 parts of photosensitizer, 1-5 parts of defoamer and 0.1-1.5 parts of color paste.

[0036] The reactive diluent is selected from monofunctional acrylate monomers or multifunctional acrylate monomers.

[0037] Optionally, the monofunctional acrylate monomer is selected from tetrahydrofuran acrylate (THFA), cyclotrimethylolpropane formal acrylate, 4-hydroxybutyl acrylate or isobornyl methacrylate; the difunctional acrylate monomer is selected from 1,6-hexanediol diacrylate, polyethylene glycol (200) diacrylate, glycidyl methacrylate, and the multifunctional acrylate monomer is selected from trimethylolpropane triacrylate or pentaerythritol triacrylate.

[0038] The photoinitiator is a mixture of a free radical photoinitiator and a cationic photoinitiator, the cationic initiator is an iodonium salt and a sulfonium salt, and the mass ratio of the free radical photoinitiator to the cationic photoinitiator is 3:1-1:3, preferably 2:1-1:2.

[0039] Optionally, the free radical photoinitiator is selected from TPO (diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide), 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone) or 819 (phenyl bis (2,4,6-trimethylbenzoyl) phosphine oxide), and the cationic photoinitiator is selected from 6976 (diphenyl [4- (phenylthio) phenyl] - hexafluoroantimonate sulfonium), PAG-201S (mixed triphenyl hexafluoroantimonate sulfonium salt), PAG-30201 (bis (4-tert-butylphenyl) iodonium hexafluorophosphate) or 820 (4,4-dimethyldiphenyl iodonium hexafluorophosphate).

[0040] The photosensitizer is selected from an anthracene photosensitizer and an aromatic ketone photosensitizer. Optionally, the photosensitizer is selected from PSS-306 (9,10-diethoxy-2-ethylanthracene) or ITX (2-isopropylthioxanthone).

[0041] The color paste is selected from at least one of blue color paste, yellow color paste and red color paste.

[0042] The hybrid curing solder resist ink prepared by the present invention has low viscosity (viscosity of 6.5-24.8 mPa·s at 45° C.), fast curing speed (tack-free time of 15-21 seconds), high hardness (pencil hardness of 4H-5H), good adhesion to the substrate (according to ISO-2409 standard, adhesion is grade 0), and excellent comprehensive performance.

[0043] The fourth technical solution of the present invention:

[0044] The present invention also provides application of the hybrid curing solder resist ink in the manufacture of high-precision electronic circuit boards.

[0045] Compared with the prior art, the present invention has the following advantages and technical effects:

[0046] The present invention utilizes a rationally proportioned composition to produce a free radical-cationic hybrid curing solder resist ink that rapidly cures under ultraviolet light, forming a robust solder resist layer with excellent mechanical strength and chemical stability, making it suitable for solder protection of electronic components. The present invention's reactive hybrid monomer, made from acrylic acid and an oxetane monomer containing a hydroxyl or epoxy group, exhibits both a free radical-cationic dual curing mechanism, accelerating the ink's curing speed. The oxetane group also enhances the ink's adhesion, resulting in a solder resist coating with superior performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0048] Figure 1 This is the infrared spectrum of the unsaturated acid reactive hybrid monomer prepared in Example 1;

[0049] Figure 2 This is the H NMR spectrum of the unsaturated acid active hybrid monomer prepared in Example 1. DETAILED DESCRIPTION

[0050] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0051] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0052] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0053] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the description of the invention. The description and examples are intended to be illustrative only.

[0054] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0055] Unless otherwise specified, the normal temperature in the present invention is 25±2°C.

[0056] The raw materials used in the embodiments of the present invention are obtained by commercial purchase or preparation. As an example, epoxy-oxygen heterocyclic monomer TCM207 ( ) was purchased from Jiangsu Taitel New Materials Technology Co., Ltd.; ((3-ethyloxetan-3-yl)methoxy)methanol was purchased from Jiangsu Taitel New Materials Technology Co., Ltd.

[0057] Unless otherwise specified, the “parts” used in the embodiments of the present invention are “parts by mass”.

[0058] In some embodiments of the present invention, a reactive hybrid monomer is provided, the general structural formula of which is shown in formula (1):

[0059] (1)

[0061] Among them, R1 is a carbon-carbon double bond, R2 is an alkyl chain with 1 to 13 carbon atoms containing an ester group or an alkyl chain with 1 to 13 carbon atoms containing a hydroxyl group and an ester group, and R3 is an alkyl chain with 1 to 4 carbon atoms.

[0062] The above-mentioned active hybrid monomer is preferably selected from the following compounds:

[0063] 、 、 or .

[0064] The C=C double bond in the active hybrid monomer of the present invention can increase the curing speed, and the volume expansion of the cationic ring-opening polymerization of oxetane can compensate for the volume contraction of the free radical polymerization, thereby increasing the curing speed and adhesion of the ink solder mask layer to the substrate.

[0065] In some embodiments of the present invention, a method for preparing the above-mentioned active hybrid monomer is also provided, comprising the following steps: mixing an oxetane-containing compound and a catalyst, heating the mixture to 85-95° C. while stirring under nitrogen protection, adding a mixture of an unsaturated acid and an inhibitor, heating the mixture to 100-105° C. and reacting until the acid value is lower than 10 mg NaOH or KOH / g, continuing the reaction for 30 minutes, stopping heating, maintaining stirring and nitrogen conditions, cooling the mixture to 38-42° C. and discharging to obtain an active hybrid monomer, which is recorded as an unsaturated acid active hybrid monomer.

[0066] The general structural formula of the compound containing oxetane is shown in formula (2):

[0067] (2)

[0069] wherein R4 is a hydroxyl group or an epoxy group, R5 is an alkyl chain having 1 to 9 carbon atoms, and R6 is an alkyl chain having 1 to 4 carbon atoms;

[0070] The general structural formula of the unsaturated acid is shown in formula (3):

[0071] (3)

[0073] Wherein, R is an alkyl chain with 1 to 10 carbon atoms;

[0074] The molar ratio of the oxetane-containing compound to the unsaturated acid is 1:(1-2), preferably 1:1.5.

[0075] The present invention utilizes acrylic acid to undergo an esterification reaction with an epoxy group or hydroxyl group-containing oxetane to connect a C=C double bond with the oxetane, thereby preparing a reactive hybrid monomer. The reactive hybrid monomer can react with other components under ultraviolet light to form a cross-linked network, thereby enhancing the curing performance and adhesion of the solder resist ink.

[0076] In some embodiments of the present invention, the oxetane-containing compound is selected from ((3-ethyloxetan-3-yl)methoxy)methanol, 3-ethyl-3-{[(oxiran-2-yl)methoxy]methyl}oxetane (TCM207), 3-methyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane or 3-butyl-3-(((9-(oxiran-2-yl)nonyl)oxy) The unsaturated acid is acrylic acid or 11-dodecenoic acid; the catalyst is selected from triphenylphosphine or tetrabutylammonium bromide, preferably triphenylphosphine, and the amount of the catalyst added is 0.25% of the total mass of acrylic acid (or 11-dodecenoic acid) and oxetane; the polymerization inhibitor is selected from p-hydroxyanisole or hydroquinone, preferably p-hydroxyanisole, and the amount of the polymerization inhibitor added is 0.8% of the total mass of acrylic acid (or 11-dodecenoic acid) and oxetane.

[0077] In other embodiments of the present invention, a hybrid curable solder resist ink containing the above-mentioned reactive hybrid monomer is further provided, wherein the mass ratio of the reactive hybrid monomer to the color paste is (300-700): (1-1.5).

[0078] In some embodiments of the present invention, the hybrid curable solder resist ink comprises the following raw materials, calculated by weight: 30-70 parts of a reactive hybrid monomer, 40-60 parts of a reactive diluent, 3-10 parts of a photoinitiator, 1-2 parts of a photosensitizer, 0-5 parts of a defoamer, and 0.1-1.5 parts of a colorant. Preferably, the hybrid curable solder resist ink comprises the following raw materials, calculated by weight: 40-60 parts of a reactive hybrid monomer, 40-60 parts of a reactive diluent, 3-10 parts of a photoinitiator, 1-2 parts of a photosensitizer, 1-5 parts of a defoamer, and 0.1-1.5 parts of a colorant.

[0079] In some embodiments of the present invention, the reactive diluent is selected from a monofunctional acrylate monomer or a multifunctional acrylate monomer. For example, the monofunctional acrylate monomer is selected from tetrahydrofuran acrylate, cyclotrimethylolpropane formal acrylate, 4-hydroxybutyl acrylate, or isobornyl methacrylate; the difunctional acrylate monomer is selected from 1,6-hexanediol diacrylate, polyethylene glycol (200) diacrylate, and glycidyl methacrylate; and the multifunctional acrylate monomer is selected from trimethylolpropane triacrylate or pentaerythritol triacrylate. These monomers can reduce the viscosity of the ink and react with the hybrid cationic monomer to further promote the cross-linking and curing of the ink, thereby ensuring the solder mask effect.

[0080] In some embodiments of the present invention, the photoinitiator is a mixture of a free radical photoinitiator and a cationic photoinitiator, wherein the cationic photoinitiator is an iodonium salt and a sulfonium salt, and the mass ratio of the free radical photoinitiator to the cationic photoinitiator is 3:1 to 1:3, preferably 2:1 to 1:2. The free radical initiator and the cationic initiator absorb energy from an ultraviolet light source to excite free radicals or cations to generate active species, thereby initiating a curing reaction of the monomer. Exemplarily, the free radical photoinitiator is selected from TPO (diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide), 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone), or 819 (phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide), and the cationic photoinitiator is selected from 6976 (diphenyl[4-(phenylthio)phenyl]-sulfonium hexafluoroantimonate), PAG-201S (mixed triphenylsulfonium hexafluorophosphate), PAG-30201 (bis(4-tert-butylphenyl)iodonium hexafluorophosphate), or 820 (4,4-dimethyldiphenyliodonium hexafluorophosphate). The photosensitizer is selected from one of anthracene photosensitizers and aromatic ketone photosensitizers, and can absorb ultraviolet light and release active substances to accelerate the curing reaction, ensuring that the ink cures in a short time and reducing the impact of the environment on the curing process. In the following embodiments of the present invention, the photosensitizer is selected from PSS-306 (9,10-diethoxy-2-ethylanthracene) or ITX (2-isopropylthioxanthone). In the following embodiments of the present invention, the defoamer is BYK-A555, a silicone-free foam-breaking polymer solution with a density of 0.88 g / mL (20°C), a flash point of 43°C, and a refractive index of 1.507 (20°C). BYK-A555 effectively eliminates foam generated during the production, packaging, and application processes. Its high defoaming efficiency promotes the formation of a smooth, uniform film during the ink curing process, improving coverage without affecting the basic properties of the ink system, maintaining the original performance of the ink. The colorant is selected from at least one of blue, yellow, and red colorants.

[0081] In some embodiments of the present invention, the preparation method of the hybrid curable solder resist ink is as follows: accurately weigh the raw materials according to the mass fraction, first, preliminarily mix the active hybrid monomer and the active diluent to ensure their uniform distribution in the system; then, add the photoinitiator, photosensitizer and defoamer, continue stirring and mixing, and finally add the color paste and stir and mix to ensure uniform dispersion of the components, and ultrasonically disperse the mixed system to ensure that the pigment particles in the color paste are fully dispersed in the ink to obtain uniform color and good fluidity.

[0082] In an embodiment of the present invention, the prepared hybrid curable solder resist ink is coated on the surface of the substrate and cured using an ultraviolet light source. The ultraviolet curing conditions include: ultraviolet light intensity: 15~45mW / cm 2UV light wavelength range: 365-405nm; Exposure time: generally between 10 and 30 seconds, depending on film thickness. UV light irradiation initiates a reaction between the photoinitiator and photosensitizer, generating free radicals or cations, which initiates a cross-linking reaction, rapidly curing the ink and forming a strong solder mask layer. The film, once cured to the point of being surface-free, is then placed in an oven for post-curing to allow the internal curing reaction to fully complete. The cured solder mask ink undergoes performance testing, including adhesion testing using a QFH-A scratch tester in accordance with ISO-2409 to assess adhesion. Mechanical strength testing: Scratch hardness testing is performed in accordance with GB / T 6739-2022 to assess the mechanical strength of the cured ink. Curing speed: Using the finger touch method, press the film surface after curing. If dry and non-sticky, the film is considered surface-free. The surface-free time is used to characterize the cure speed.

[0083] The hybrid curing solder resist ink prepared by the present invention has low viscosity (viscosity of 6.5-24.8 mPa·s at 45° C.), fast curing speed (tack-free time of 15-21 seconds), high hardness (pencil hardness of 4H-5H), good adhesion to the substrate (according to ISO-2409 standard, adhesion is grade 0), and excellent comprehensive performance.

[0084] The hybrid curable solder resist ink provided by the embodiment of the present invention can be used for manufacturing high-precision electronic circuit boards.

[0085] It should be pointed out that the matters not described in detail in the present invention are conventional operating means in this field and are not the focus of the present invention.

[0086] The technical solution of the present invention is further illustrated by the following examples.

[0087] Example 1

[0088] Preparation of unsaturated acid reactive hybrid monomers:

[0089] (1) Weigh TCM207 and acrylic acid in a molar ratio of 1:1.5, 0.25 wt% of the total weight of TCM207 and acrylic acid, and 0.8 wt% of triphenylphosphine based on the total weight of TCM207 and acrylic acid for use;

[0090] (2) TCM207 and triphenylphosphine were added to a 250 mL four-necked flask, stirred under a nitrogen atmosphere, and the oil bath was heated to 90°C. A mixture of acrylic acid and p-hydroxyanisole was added dropwise, and the addition was completed within 30 minutes. The mixture was then heated to 105°C for insulation reaction. Samples were taken at regular intervals to test the acid value until the acid value of the system was lower than 10 mg NaOH / g. The reaction was continued for 30 minutes, and the heating was stopped. The stirring and nitrogen conditions were maintained, and the temperature was lowered to 40°C for discharging to obtain an unsaturated acid active hybrid monomer, the structural formula of which is as follows: The infrared spectrum of the unsaturated acid active hybrid monomer prepared in this example is as follows: Figure 1 As shown, the H NMR spectrum is as Figure 2 shown.

[0091] Example 2

[0092] Compared with Example 1, the unsaturated acid acrylic acid was replaced with 11-dodecenoic acid to ensure that the molar ratio of TCM207 to 11-dodecenoic acid was 1:1.5. The other steps were the same as in Example 1. The structural formula of the unsaturated acid reactive hybrid monomer obtained in this example is as follows: .

[0093] Example 3

[0094] Compared with Example 1, the oxetane compound TCM207 was used to replace ((3-ethyloxetan-3-yl)methoxy)methanol, and the molar ratio of ((3-ethyloxetan-3-yl)methoxy)methanol to acrylic acid was ensured to be 1:1.5. The other steps were the same as in Example 1. The structural formula of the unsaturated acid reactive hybrid monomer obtained in this example is as follows .

[0095] Example 4

[0096] (1) Weigh 3-methyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane and acrylic acid in a molar ratio of 1:1.5, 0.25 wt% of the total weight of 3-methyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane and acrylic acid at p-hydroxyanisole, and 0.8 wt% of the total weight of 3-methyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane and acrylic acid at triphenylphosphine for use;

[0097] (2) Add 3-methyl-3-(((9-(oxirane-2-yl)nonyl)oxy)methyl)oxetane and triphenylphosphine into a 250 mL four-necked flask, stir under nitrogen atmosphere and heat the oil bath to 90°C, start adding a mixture of acrylic acid and p-hydroxyanisole dropwise, complete the addition within 30 minutes, then heat to 105°C and keep the reaction warm. Samples are taken at regular intervals to test the acid value until the acid value of the system is lower than 10 mg NaOH / g. Continue the reaction for 30 minutes, stop heating, maintain stirring and nitrogen conditions, cool to 40°C and discharge to obtain an unsaturated acid active hybrid monomer, the structural formula of which is as follows: .

[0098] The preparation method for 3-methyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane is as follows: First, 3-methyl-3-oxetanemethanol (1 mol) is added to an alkaline potassium hydroxide solution and stirred at room temperature for 0.5 h. Then, tetrabutylammonium bromide (a phase transfer catalyst) and 2-(9-chlorononyl)oxirane (2 mol) are added and reacted at 60°C for 10 h. After the reaction, the mixture is diluted with dichloromethane, filtered, dried over anhydrous sodium sulfate, filtered, and finally distilled under reduced pressure to obtain the desired product.

[0099] Example 5

[0100] (1) Weigh 3-butyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane and acrylic acid in a molar ratio of 1:1.5, 0.25 wt% of p-hydroxyanisole, and 0.8 wt% of triphenylphosphine;

[0101] (2) 3-Butyl-3-(((9-(2-oxirane-1-yl)nonyl)oxy)methyl)oxetane and triphenylphosphine were added to a 250 mL four-necked flask, stirred under a nitrogen atmosphere, and the oil bath was heated to 90°C. A mixture of acrylic acid and p-hydroxyanisole was added dropwise, and the addition was completed within 30 minutes. The temperature was then raised to 105°C for insulation reaction. Samples were taken at regular intervals to test the acid value until the acid value of the system was lower than 10 mg NaOH / g. The reaction was continued for 30 minutes. The heating was stopped, stirring and nitrogen conditions were maintained, and the temperature was lowered to 40°C for discharge to obtain an unsaturated acid active hybrid monomer, the structural formula of which is as follows: .

[0102] The preparation method for 3-butyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane is as follows: First, 3-butyl-3-oxetanemethanol (1 mol) is added to an alkaline potassium hydroxide solution and stirred at room temperature for 0.5 h. Then, tetrabutylammonium bromide (a phase transfer catalyst) and 2-(9-chlorononyl)oxirane (2 mol) are added and reacted at 60°C for 10 h. After the reaction, the mixture is diluted with dichloromethane, filtered, dried over anhydrous sodium sulfate, filtered, and finally distilled under reduced pressure to obtain the desired product.

[0103] Example 6

[0104] This embodiment provides a hybrid curable solder resist ink containing a reactive hybrid monomer, which is composed of the following raw materials, calculated by weight: 40 parts of the reactive hybrid monomer in Example 1, 60 parts of a reactive diluent, 5 parts of a photoinitiator, 2 parts of a photosensitizer, 3 parts of a defoamer, and 1 part of a color paste, wherein the reactive diluent used in this embodiment is tetrahydrofuran acrylate (THFA); the photoinitiator is a free radical photoinitiator 1173 and a cationic photoinitiator 6976, with a mass ratio of 2:3; the photosensitizer is ITX; the color paste is a green color paste made by mixing yellow and blue color pastes; and the defoamer is BYK-A555.

[0105] The preparation method of the hybrid curable solder resist ink containing the above-mentioned active hybrid monomer is as follows: at room temperature, cationic photoinitiator 6976 and photosensitizer ITX are added to the active hybrid monomer in sequence, and stirred until the solution is clear, and then active diluent and free radical photoinitiator 1173 are added, and stirred until the solution is clear, and finally color paste and defoaming agent are added, and mixed evenly to obtain a hybrid curable solder resist ink.

[0106] The hybrid curable solder mask ink was used to cure the coating: the copper clad laminate was sanded, and a wire rod applicator was used to prepare the coating, which was then placed in a UV curing machine for curing (UV light intensity: 30 mW / cm 2 ; UV light wavelength range: 365nm; curing time: 15 seconds), and then placed in a 150℃ oven for post-curing for 2 hours to form a solder mask layer.

[0107] Example 7

[0108] This embodiment provides a hybrid curable solder resist ink containing a reactive hybrid monomer, which is composed of the following raw materials, calculated by weight: 50 parts of the reactive hybrid monomer in Example 3, 50 parts of a reactive diluent, 5 parts of a photoinitiator, 2 parts of a photosensitizer, 3 parts of a defoamer, and 1 part of a color paste, wherein the reactive diluent used in this embodiment is THFA; the photoinitiator is a free radical photoinitiator 1173 and a cationic photoinitiator 6976, and the mass ratio of the two is 2:3; the photosensitizer is ITX; the color paste is a green color paste made by mixing yellow and blue color pastes; and the defoamer is BYK-A555.

[0109] The preparation method of the hybrid curable solder resist ink containing the above-mentioned active hybrid monomer is as follows: at room temperature, cationic photoinitiator 6976 and photosensitizer ITX are added to the active hybrid monomer in sequence, and stirred until the solution is clear, and then active diluent and free radical photoinitiator 1173 are added, and stirred until the solution is clear, and finally color paste and defoaming agent are added, and mixed evenly to obtain a hybrid curable solder resist ink.

[0110] The hybrid curable solder mask ink was used to cure the coating: the copper clad laminate was sanded, and a wire rod applicator was used to prepare the coating, which was then placed in a UV curing machine for curing (UV light intensity: 30 mW / cm 2 ; UV light wavelength range: 365nm; curing time: 15 seconds), and then placed in a 150℃ oven for post-curing for 2 hours to form a solder mask layer.

[0111] Example 8

[0112] This embodiment provides a hybrid curable solder resist ink containing a reactive hybrid monomer, which is composed of the following raw materials, calculated by weight: 60 parts of the reactive hybrid monomer in Example 4, 40 parts of a reactive diluent, 5 parts of a photoinitiator, 2 parts of a photosensitizer, and 1.5 parts of a color paste, wherein the reactive diluent used in this embodiment is THFA; the photoinitiator is a free radical photoinitiator 1173 and a cationic photoinitiator 6976, and the mass ratio of the two is 2:3; the photosensitizer is ITX; and the color paste is a green color paste made by mixing yellow and blue color pastes.

[0113] The preparation method of the hybrid curable solder resist ink containing the above-mentioned reactive hybrid monomer is as follows: at room temperature, cationic photoinitiator 6976 and photosensitizer ITX are sequentially added to the reactive hybrid monomer, stirred until the solution is clear, then reactive diluent and free radical photoinitiator 1173 are added, stirred until the solution is clear, and finally color paste is added and mixed evenly to obtain a hybrid curable solder resist ink.

[0114] The hybrid curable solder mask ink was used to cure the coating: the copper clad laminate was sanded, and a wire rod applicator was used to prepare the coating, which was then placed in a UV curing machine for curing (UV light intensity: 30 mW / cm 2 ; UV light wavelength range: 365nm; curing time: 15 seconds), and then placed in a 150℃ oven for post-curing for 2 hours to form a solder mask layer.

[0115] Example 9

[0116] The raw material composition and preparation method of the hybrid curable solder resist ink containing the active hybrid monomer in this embodiment are the same as those in Example 5, with the only difference being the active hybrid monomer. The active hybrid monomer in this embodiment is the one prepared in Example 5.

[0117] The hybrid curable solder resist ink prepared in this embodiment was used to form a solder resist layer using the same method as in Example 5.

[0118] Example 10

[0119] This embodiment provides a hybrid curable solder resist ink containing a reactive hybrid monomer, which is composed of the following raw materials in parts by mass: 30 parts of the reactive hybrid monomer in Example 1, 40 parts of a reactive diluent, 3 parts of a photoinitiator, 1 part of a photosensitizer, 1 part of a defoamer, and 0.1 part of a color paste, wherein the reactive diluent used in this embodiment is 1,6-hexanediol diacrylate; the photoinitiator is a free radical photoinitiator TPO and a cationic photoinitiator PAG-30201, and the mass ratio of the two is 1:1; the photosensitizer is PSS-306; the color paste is a yellow color paste; and the defoamer is BYK-A555.

[0120] The preparation method of the hybrid curable solder resist ink containing the active hybrid monomer in this embodiment is the same as that in Example 5. The hybrid curable solder resist ink prepared in this embodiment is formed into a solder resist layer using the same method as in Example 5.

[0121] Example 11

[0122] This embodiment provides a hybrid curable solder resist ink containing a reactive hybrid monomer, which is composed of the following raw materials, calculated by weight: 50 parts of the reactive hybrid monomer in Example 1, 50 parts of a reactive diluent, 7 parts of a photoinitiator, 2 parts of a photosensitizer, 5 parts of a defoamer, and 0.8 parts of a color paste, wherein the reactive diluent used in this embodiment is trimethylolpropane triacrylate (CTFA); the photoinitiator is a free radical photoinitiator TPO and a cationic photoinitiator 820, and the mass ratio of the two is 3:1; the photosensitizer is PSS-306; the color paste is a red color paste; and the defoamer is BYK-A555.

[0123] The preparation method of the hybrid curable solder resist ink containing the active hybrid monomer in this embodiment is the same as that in Example 5. The hybrid curable solder resist ink prepared in this embodiment is formed into a solder resist layer using the same method as in Example 5.

[0124] Comparative Example 1

[0125] The raw material composition and preparation method of the hybrid curing solder resist ink containing the active hybrid monomer in this comparative example are the same as those in Example 5, except that the active hybrid monomer is different. The active hybrid monomer in this comparative example is the oxetane monomer TCM101 ( ).

[0126] The hybrid curable solder resist ink prepared in this comparative example was used to form a solder resist layer using the same method as in Example 5.

[0127] Comparative Example 2

[0128] The raw material composition and preparation method of the hybrid curing solder mask ink containing the active hybrid monomer in this comparative example are the same as those in Example 5, with the only difference being that the active hybrid monomer is different. The active hybrid monomer in this comparative example is bisphenol A epoxy resin (E51).

[0129] The hybrid curable solder resist ink prepared in this comparative example was used to form a solder resist layer using the same method as in Example 5.

[0130] Comparative Example 3

[0131] The raw material composition and preparation method of the hybrid curing solder resist ink containing the active hybrid monomer in this comparative example are the same as those in Example 5, except that the active hybrid monomer is different. The active hybrid monomer in this comparative example is the epoxy-oxygen heterocyclic monomer TCM207 ( ).

[0132] The hybrid curable solder resist ink prepared in this comparative example was used to form a solder resist layer using the same method as in Example 5.

[0133] The solder resist layers prepared in the above embodiments and comparative examples were subjected to performance tests, and the test methods were as follows:

[0134] Pencil hardness: tested in accordance with GB / T 6739-2022.

[0135] Adhesion: Tested using a QFH-A scratch tester in accordance with ISO-2409.

[0136] Curing speed: Use the finger touch method to press the film surface with your fingers after light curing. If it is dry and not sticky, it is surface dry. The length of time it takes to reach surface dry is used to characterize its curing speed.

[0137] surface Test results of each group

[0138]

[0139] The test results in Table 1 show that the hybrid curable solder mask inks in Examples 5-10 of the present invention have fast curing speeds, good adhesion, and high hardness. The solder mask coating using an oxygen heterocyclic monomer in Comparative Example 1 has a slow curing speed and incomplete curing due to the presence of hydroxyl groups in the monomer structure, resulting in low hardness. The low ring-opening rate of the oxygen heterocyclic four-membered ring leads to poor adhesion. While the bisphenol A epoxy resin in Comparative Example 2 improves adhesion due to the presence of epoxy groups in the molecule, the system has high viscosity and may clog the nozzle during inkjet printing. In Comparative Example 3, the hardness meets the requirements, but the oxygen heterocyclic has an induction period, resulting in a slow curing speed. Furthermore, the epoxy groups in the molecule suffer from severe post-curing, with some epoxy groups remaining unopened after light curing. The incomplete curing of the system leads to poor adhesion.

[0140] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. Application of a hybrid curing solder resist ink in the manufacture of high-precision electronic circuit boards, characterized in that: The hybrid curable solder resist ink is composed of the following raw materials, calculated by weight: 30-70 parts of reactive hybrid monomer, 40-60 parts of reactive diluent, 3-10 parts of photoinitiator, 1-2 parts of photosensitizer, 0-5 parts of defoamer and 0.1-1.5 parts of color paste; The reactive diluent is selected from monofunctional acrylate monomers or multifunctional acrylate monomers; The monofunctional acrylate monomer is selected from tetrahydrofuran acrylate, cyclotrimethylolpropane formal acrylate, 4-hydroxybutyl acrylate or isobornyl methacrylate; the multifunctional acrylate monomer is selected from trimethylolpropane triacrylate or pentaerythritol triacrylate; The active hybrid monomer is selected from the following compounds: or .

2. The use according to claim 1, characterized in that The active hybrid monomer is synthesized by using an oxetane-containing compound and an unsaturated acid as raw materials through an esterification reaction.

3. The use according to claim 2, characterized in that The preparation method of the active hybrid monomer comprises the following steps: mixing an oxetane-containing compound and a catalyst, heating the mixture to 85-95° C. while stirring under nitrogen protection, adding a mixture of an unsaturated acid and a polymerization inhibitor, heating the mixture to 100-105° C. for reaction until the acid value is lower than 10 mg NaOH or KOH / g, continuing the reaction for 30 minutes, stopping heating, maintaining stirring and nitrogen conditions, cooling the mixture to 38-42° C. for discharging, and obtaining the active hybrid monomer.

4. The use according to claim 3, characterized in that The oxetane-containing compound is selected from 3-methyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane or 3-butyl-3-(((9-(oxiran-2-yl)nonyl)oxy)methyl)oxetane; The structure of the unsaturated acid is generally selected from acrylic acid; The molar ratio of the oxetane-containing compound to the unsaturated acid is 1:(1-2).

5. The use according to claim 3, characterized in that The catalyst is selected from triphenylphosphine or tetrabutylammonium bromide; The polymerization inhibitor is selected from p-hydroxyanisole or hydroquinone.

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