Eugenol-modified alkali-soluble light-cured epoxy resin as well as preparation method and application thereof

Abstract

The invention provides eugenol-modified alkali-soluble light-cured epoxy resin and a preparation method and application thereof.The preparation method comprises the steps that firstly, mercaptoalkanol serves as a chain extender for chain extension of eugenol, alcoholic hydroxyl groups are introduced, then epoxidation reaction is conducted on the eugenol and epoxy chloropropane, and an epoxy intermediate monomer is obtained; then carrying out ring-opening polymerization reaction modification on the epoxy intermediate monomer and acrylic acid, and finally carrying out esterification reaction with unsaturated anhydride to obtain the eugenol modified alkali-soluble light-cured epoxy resin. In the first step of a synthesis path, mercaptoalkanol is used for carrying out chain extension on eugenol, alcoholic hydroxyl is introduced, and a designed amount of epoxy units are introduced through epoxidation reaction; wherein mercaptoalkanols with different lengths can be selectively added, intermediate connection structures of different alkane chains are introduced into phenolic hydroxyl groups and alcoholic hydroxyl groups, a series of epoxy molecules containing bio-based benzene ring structures are synthesized, and the flexible alkane chains have a remarkable promotion effect on direct-current voltage breakdown strength tolerance of a cured film formed by curing an ink product.

Description

Technical Field

[0001] The invention relates to the technical field of modified light-curing epoxy resin and application thereof, and in particular to a eugenol-modified alkali-soluble light-curing epoxy resin and a preparation method and application thereof. Background Art

[0002] Due to its excellent performance in high-precision manufacturing and rapid prototyping, photocurable resins are manufactured into customized materials with strong and complex structures and are widely used in semiconductor industries such as integrated circuits, electronic packaging and photoresists.

[0003] As advanced chip manufacturing technology develops towards multi-level, multi-dimensional and multi-functional, in order to match the performance indicators of high-density integrated circuits, more stringent standards are proposed for the solder-resistant coatings of printed circuit boards (PCBs) equipped with corresponding semiconductor components. For example, in order to meet the high-speed, low-latency and anti-interference communication capabilities of 5G communication technology, electronic packaging coatings need to have excellent heat resistance and mechanical strength and reliable electrical insulation capabilities to ensure safe and accurate data transmission. In addition, driven by the ever-expanding industrial market demand, the design of coatings tends to be flexible and customizable, such as ductility, low surface energy, interface compatibility, etc., while traditional resin-based materials are difficult to meet the use requirements of diverse scenarios. Epoxy resin is the most widely used thermosetting resin, including PCB substrates, due to its diverse performance characteristics. At the same time, epoxy resin is also the most commonly used photocurable precursor for electronic packaging coatings. The design and optimization of epoxy monomer structure is particularly critical. Many studies have used simple and effective means to integrate existing materials to further synthesize and improve functional epoxy resins.

[0004] For example, the Chinese invention patent application of the University of Electronic Science and Technology of China, "A method for modifying epoxy resin composite materials with nano-inorganic fillers" (CN109943021A), discloses a method for modifying epoxy resin composite materials with nano-inorganic fillers. The method utilizes nano-inorganic fillers to modify epoxy resin composite materials, and uses a high-pressure micronization device for nano-nization of micron particles to disperse the inorganic filler in the epoxy resin liquid, which greatly improves the problem that the nanoparticles are very easy to agglomerate due to their high surface efficiency and affect the performance of the composite material, and greatly improves the dispersibility of the inorganic filler in the epoxy resin.

[0005] Another example is the Chinese invention patent "A rigid acrylic ester UV light-cured modified tung oil resin and its preparation method and application" (CN111909075B) discloses a rigid acrylic ester UV light-cured modified tung oil resin with a high double bond content and its preparation method and application. The rigid acrylic ester UV light-cured modified tung oil resin with a high double bond content contains a relatively rigid cyclic tetra / hexahydrophthalimide group and a relatively large number of (meth)acrylate structures in its structure. When subjected to UV radiation, multiple acrylate double bonds polymerize to form a cross-linked network; at the same time, multiple hydroxyls generated after the epoxy groups of (meth) glycidyl acrylate are consumed and the relatively polar tetra / hexahydrophthalimide structure enhances the intermolecular force between the cured film and the substrate surface.

[0006] However, the biggest problem is that in the prior art including the above patent documents, almost all epoxy resins are derived from petroleum-based raw materials, which largely violates environmental protection and sustainable considerations. Developing value-added chemicals based on biomass resources to replace non-renewable energy is very attractive in this regard, and is also an important way to convert green renewable raw materials in addition to being used as fuel.

[0007] Therefore, it is necessary to provide a method for preparing high-performance photocurable epoxy resin using renewable raw materials, and optimize and improve it to obtain a functional bio-based photocurable solder resist ink with high temperature resistance, strong toughness, and resistance to DC voltage breakdown. Summary of the invention

[0008] The present invention provides a eugenol-modified alkali-soluble photocurable epoxy resin and a preparation method and application thereof, wherein in the first step of the synthesis route, eugenol is chain-extended by mercaptoalkanol and alcoholic hydroxyl groups are introduced, and a designed amount of epoxy units are introduced by epoxidation reaction. Mercaptoalkanols of different lengths can be added, and intermediate connection structures of different alkane chains are introduced into the phenolic hydroxyl groups and alcoholic hydroxyl groups to synthesize a series of epoxy molecules containing bio-based benzene ring structures, and the flexible alkane chains have a significant promoting effect on the DC voltage breakdown strength tolerance of the cured film formed by the ink product.

[0009] To achieve the above objectives, the present invention is implemented by adopting a technical solution consisting of the following technical measures.

[0010] In one aspect, the present invention provides a eugenol-modified alkali-soluble photocurable epoxy resin, the chemical structure of which is as follows:

[0011]

[0012] or:

[0013]

[0014] In the formula, R is any one of the following structures:

[0015]

[0016] In the above chemical structural formula, “…” indicates the position where the chemical bonds are connected.

[0017] On the other hand, the present invention also provides a method for preparing the above-mentioned eugenol-modified alkali-soluble photocurable epoxy resin, which is to first extend the chain of eugenol (CAS: 97-53-0) with mercaptoalkanol as a chain extender and introduce alcoholic hydroxyl groups, then perform an epoxidation reaction with epichlorohydrin to obtain an epoxy intermediate monomer, then perform a ring-opening polymerization reaction modification with acrylic acid, and finally perform an esterification reaction with an unsaturated acid anhydride to obtain the eugenol-modified alkali-soluble photocurable epoxy resin. It should be noted that those skilled in the art can obtain specific preparation steps according to the reaction sequence shown above, especially the ring-opening polymerization modification with acrylic acid and the esterification reaction with an unsaturated acid anhydride, which is a conventional synthetic route for preparing alkali-soluble photocurable epoxy resins in the art; therefore, the technical scheme provided by the present invention below does not mean the sole designation or limitation of the preparation method of the eugenol-modified alkali-soluble photocurable epoxy resin.

[0018] In one preferred technical solution, the method for preparing the eugenol-modified alkali-soluble photocurable epoxy resin mainly comprises the following steps:

[0019] (1) in an air atmosphere, eugenol (EU), mercaptoalkanol and a photoinitiator for a thiol-ene click chemistry reaction are added to a reaction vessel, and the reaction is carried out for 12 to 24 hours with stirring under ultraviolet light irradiation at a photoinitiating wavelength of the photoinitiator for the thiol-ene click chemistry reaction to obtain a dihydroxy compound modified with eugenol;

[0020] Wherein, the mercaptoalkanol is an alkyl chain compound with a hydroxyl group at one end of the molecular structure and a mercapto group at the other end, and the molar ratio of the eugenol to the mercaptoalkanol is 1:(1-1.1);

[0021] (2) adding epichlorohydrin and an epoxidation catalyst to the dihydroxy compound modified with eugenol obtained in step (1), mixing and dissolving them thoroughly, stirring and reacting them at a temperature of 60 to 80° C. for 8 to 24 hours, and separating and obtaining an epoxy intermediate monomer;

[0022] The reaction is carried out at a temperature of 60 to 80° C. for 8 to 24 hours, and a ring-closing reaction is performed during the reaction, or a ring-closing reaction is performed after the reaction time is reached;

[0023] The molar ratio of the dihydroxy compound modified with eugenol to epichlorohydrin is 1:(5-12);

[0024] (3) In an air atmosphere, the epoxy intermediate monomer obtained in step (2), acrylic acid and a solvent are added to a reaction vessel, and a cyclic ester ring-opening polymerization catalyst and a polymerization inhibitor are added. After being fully mixed, the temperature is adjusted to 100 to 125° C. and stirred for reaction for 8 to 16 hours to obtain an acrylic acid-modified epoxy intermediate monomer;

[0025] (4) Cooling the acrylic acid-modified epoxy intermediate monomer obtained in step (3) to 70-80° C., then adding unsaturated acid anhydride, and continuing to stir and react at 85-100° C. for 6-12 hours to obtain a eugenol-modified alkali-soluble photocurable epoxy resin.

[0026] In this article, the "eugenol" (CAS: 97-53-0) described in step (1) is a lignin-derived structural monomer, which can be commercially available or homemade, and the purity requirement is usually chemical raw material grade.

[0027] In one of the technical schemes, the mercaptoalkanol selected in step (1) includes at least one of mercaptomethanol, 2-mercaptoethanol, 3-mercaptopropanol, 4-mercaptobutanol, 5-mercaptopentanol, 6-mercaptohexanol, 7-mercaptoheptanol, 8-mercaptooctanol, 9-mercaptononanol, 10-mercaptodecanol, 11-mercaptoundecanol, 12-mercaptododecanol, 13-mercaptotridecanol, 14-mercaptotetradecanol, 15-mercaptopentadecanol, 16-mercaptohexadecanol, 17-mercaptoheptadecanol or 18-mercaptooctadecanol.

[0028] Herein, the photoinitiator for thiol-ene click chemistry reaction described in step (1) is a photoinitiator commonly used in the technical field for thiol-ene click chemistry reaction. Technicians in the technical field can select a suitable photoinitiator for thiol-ene click chemistry reaction according to actual needs, and determine the corresponding appropriate addition amount and optimal wavelength of ultraviolet light according to the existing technical information such as the commercial instructions / operation manual of the specifically selected thiol-ene click chemistry reaction photoinitiator.

[0029] In one of the technical solutions, the photoinitiator for the thiol-ene click chemistry reaction in step (1) is selected from any one of 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methylpropiophenone, benzophenone, dibenzophenone, and (2,4,6-trimethylbenzoyl)diphenylphosphine oxide.

[0030] In order to better illustrate the present invention and provide a technical solution for reference, when the photoinitiator for the thiol-ene click chemistry reaction in step (1) is selected as 2-hydroxy-2-methylpropiophenone, ultraviolet light with a wavelength of 395 nm should be used for irradiation, and the amount added is 2.5 to 3.5 wt % of the total mass of eugenol and mercaptoalkanol in step (1).

[0031] Herein, the catalyst for epoxidation reaction in step (2) is a catalyst commonly used for epoxidation reaction in the technical field, and technicians in the technical field can select a suitable catalyst for epoxidation reaction according to actual needs.

[0032] In one of the technical solutions, the catalyst for the epoxidation reaction in step (2) is selected from any one of tetrabutylammonium bromide, tetramethylammonium bromide, and benzyltriethylammonium chloride; the amount of the catalyst added in the epoxidation reaction is 8 to 12% of the molar amount of the dihydroxy compound modified with eugenol in step (2).

[0033] Herein, the ring-closing reaction treatment in step (2) is a conventional process selection in the epoxidation reaction process. Those skilled in the art can directly select an appropriate method for the ring-closing reaction treatment based on the common knowledge of epoxidation reactions or conventional epoxidation reaction processes in the art.

[0034] In order to better illustrate the present invention and provide a technical solution for reference, the reaction described in step (2) is carried out at a temperature of 60 to 80° C. for 8 to 24 hours, and a ring-closing reaction is carried out during the reaction. Specifically, a NaOH aqueous solution having a mass of solute NaOH 3 to 5 times that of the dihydroxy compound and a mass concentration of 20 to 40 wt% is added to the reaction solution (the dihydroxy compound modified with eugenol, epichlorohydrin and the catalyst for the epoxidation reaction), and the reaction is carried out together at a temperature of 60 to 80° C. for 8 to 24 hours.

[0035] In order to better illustrate the present invention and provide a technical solution for reference, the reaction is carried out at a temperature of 60 to 80° C. for 8 to 24 hours in step (2), and a closed-loop reaction is carried out after the reaction time is reached. Specifically, after the reaction time is reached, after the product is cooled to room temperature, a NaOH aqueous solution having a mass of solute NaOH that is 3 to 5 times that of the dihydroxy compound and a mass concentration of 20 to 40 wt% is added under stirring, and stirring is continued for 15 hours.

[0036] In one of the technical solutions, the epoxy intermediate monomer is separated in step (2). Since epichlorohydrin is used as both a reactant and a solvent, and the reaction product is also a liquid, rotary evaporation separation is preferably used.

[0037] It should be noted that the separation process in step (2) is usually accompanied by conventional process operations such as liquid separation and washing, which are common knowledge in the technical field and will not be described here.

[0038] Herein, the cyclic ester ring-opening polymerization catalyst in step (3) is a cyclic ester ring-opening polymerization catalyst commonly used in epoxy resin ring-opening polymerization reactions in the technical field. Those skilled in the art can select a suitable cyclic ester ring-opening polymerization catalyst according to actual needs.

[0039] In one of the technical solutions, the cyclic ester ring-opening polymerization catalyst in step (3) is selected from one of triethylamine, triethanolamine, 4-dimethylaminopyridine, tetrabutylammonium bromide, tetramethylammonium chloride, N,N-dimethylbenzylamine and triphenylphosphine; the amount of the cyclic ester ring-opening polymerization catalyst added is 0.5 to 1.0 wt% of the total mass of the epoxy intermediate monomer and acrylic acid in step (3).

[0040] In this article, the solvent in step (3) is selected from conventional solvents in the art, and can be conventional solvents used in inks.

[0041] In one of the technical schemes, the solvent selected in step (3) includes at least one of a dibasic acid ester high-boiling point environmentally friendly solvent, ethylene glycol ethyl ether acetate, ethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol butyl ether acetate, propylene glycol methyl ether acetate, propylene glycol methyl ether propionate, dipropylene glycol methyl ether, propylene glycol methyl ether, trimethylbenzene and tetramethylbenzene; the amount of solvent added can refer to the conventional amount used in the process for preparing alkali-soluble light-curing epoxy resin in the technical field of this invention, or refer to the following preferred embodiment: in step (1), solvent mass: epoxy intermediate monomer mass = (0.5-4): 1.

[0042] In this article, the polymerization inhibitor in step (3) is selected from conventional polymerization inhibitors in the art, and can be polymerization inhibitors conventionally used in ink technology.

[0043] In one of the technical solutions, the polymerization inhibitor selected in step (3) includes at least one of hydroquinone, o-methyl hydroquinone, p-hydroxyanisole, p-benzoquinone and 2,6-di-tert-butyl-4-methylphenol. Preferably, the polymerization inhibitor added twice is the same polymerization inhibitor; the amount of the polymerization inhibitor added in step (3) is 0.3-1.0wt% of the total mass of the epoxy intermediate monomer and acrylic acid in step (3).

[0044] In this article, the amount of acrylic acid added in step (3) should be consistent with the amount of acrylic acid added in the conventional synthesis process for preparing alkali-soluble photocurable epoxy resins in the art, and is usually calculated based on the balanced molar amount of the chemical reaction formula, for example, the molar amount of the acrylic acid to the molar amount of the epoxy intermediate monomer is (2 to 2.1):1.

[0045] Herein, the unsaturated anhydride in step (4) is a conventional choice of unsaturated anhydride in the process of preparing alkali-soluble photocurable epoxy resin in the art. Those skilled in the art can directly select a suitable unsaturated anhydride from the relevant technical literature on preparing alkali-soluble photocurable epoxy resin in the prior art.

[0046] In this article, the amount of unsaturated anhydride added in step (4) is preferably consistent with the amount of unsaturated anhydride added in the conventional synthesis process for preparing alkali-soluble photocurable epoxy resin in the art, but it is also possible to choose to esterify with only half of the hydroxyl groups, so that the molar ratio of the unsaturated anhydride to the molar ratio of the epoxy intermediate monomer is (1 to 2.1):1.

[0047] In one of the technical solutions, the unsaturated acid anhydride in step (4) is selected from at least one of tetrahydrophthalic anhydride, itaconic anhydride, maleic anhydride, succinic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride and methylhexahydrophthalic anhydride.

[0048] Herein, the stirring reaction is a stirring reaction conventionally used in the art, including magnetic stirring or mechanical stirring, and those skilled in the art can select a suitable stirring reaction mode according to the production scale or the current process conditions. In one technical solution, the stirring reaction can be carried out at a stirring rate of 100 to 300 rpm.

[0049] On the other hand, based on the above-mentioned eugenol-modified alkali-soluble photocurable epoxy resin, the present invention also provides a high-performance photosensitive solder resist ink using the above-mentioned alkali-soluble photocurable epoxy resin as a main component, and its raw materials mainly include, by weight:

[0050] 100 parts of eugenol-modified alkali-soluble light-curing epoxy resin,

[0051] 1 to 5 parts of photoinitiator.

[0052] Herein, the photoinitiator is a photoinitiator conventionally selected for preparing photosensitive solder resist ink in the art, and those skilled in the art can select a suitable photoinitiator based on the current process conditions or existing technical literature in the art.

[0053] In one of the technical solutions, the photoinitiator is preferably at least one of 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide, 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone, 2-hydroxy-4-(2-hydroxyethoxyphenyl)-2-methylpropiophenone, 2-isopropylthioxanthone (2,4 isomers), 2-hydroxy-2-methyl-1-phenylpropiophenone, 1-hydroxycyclohexylphenylmethanol, benzoin ethyl ether, benzil dimethyl ketal, 1-hydroxyphenylhexylacetophenone, benzophenone / triethanolamine and benzophenone / acrylate active amine.

[0054] In one preferred technical solution, the high-performance photosensitive solder resist ink further comprises, by weight:

[0055] 20 to 50 parts of filler,

[0056] 1 to 25 parts of additives.

[0057] Among them, in order to improve the physical strength of the coating after the solder resist ink is used, the solder resist ink component includes a filler, and the filler is a well-known inorganic or organic filler, preferably one or more of titanium dioxide, bentonite, barium sulfate, spherical silica, nano calcium carbonate, and talc. Furthermore, it is preferred that well-known metal oxides are used as both fillers and pigments.

[0058] The additive is one or more combinations of pigments, thermal inhibitors, tackifiers, defoamers, leveling agents, coupling agents, antioxidants and rust inhibitors. Generally, the pigments, thermal inhibitors, tackifiers, defoamers, leveling agents, coupling agents, antioxidants and rust inhibitors are well known and commonly used.

[0059] The preparation method of the high-performance photosensitive solder resist ink can be prepared by mixing all components in accordance with the prior art. For example, the components are preliminarily mixed in a blender and then kneaded in a three-roll mill to obtain the high-performance photosensitive solder resist ink.

[0060] When the above solder resist ink is used, it is applied to the substrate, dried appropriately (about 60 to 90°C), and then exposed through a pattern film to obtain a cured coating film, and the unexposed portion is developed. When developing, the above solvent or a well-known halogen solvent such as trichloroethylene can be used for solvent development, but since carboxyl groups are introduced into the alkali-soluble photocurable epoxy resin modified with an acetylene-containing reactive monomer, the unexposed portion will dissolve in an alkaline aqueous solution, so alkaline development is preferably performed. For alkaline solvent development, alkali metal compounds such as sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, etc. can be selected; alkaline earth metal compounds such as calcium hydroxide can also be selected; alkaline solution ammonia water can also be selected; water-soluble organic amines such as monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monopropylamine, dipropylamine, dimethylpropylamine, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, dimethylaminoethyl methacrylate, polyethyleneimine, etc. can also be selected.

[0061] After development, it is preferred that a heat treatment be performed at about 120 to 160° C. for 1 hour to further heat cure the photocured coating film.

[0062] Generally, the high-performance photosensitive solder resist ink can be directly applied to a substrate in a liquid state or used in a state of a solder resist layer dry film formed by applying and drying on a film such as PET in advance.

[0063] The present invention has the following beneficial effects:

[0064] 1. The present invention provides a eugenol-modified alkali-soluble photocurable epoxy resin and a preparation method and application thereof. In the first step of its synthesis path, eugenol is chain-extended by mercaptoalkanol and alcoholic hydroxyl groups are introduced, and a designed amount of epoxy units are introduced by epoxidation reaction. Mercaptoalkanols of different lengths can be added, and intermediate connecting structures of different alkane chains are introduced into the phenolic hydroxyl groups and alcoholic hydroxyl groups to synthesize a series of epoxy molecules containing bio-based benzene ring structures. The flexible alkane chain has a significant promoting effect on the DC voltage breakdown strength tolerance of the cured film formed by the ink product.

[0065] 2. According to the test results, the alkane chain extension connecting unit at the designed amount gives the bio-based high cross-linking system excellent mechanical property adjustment ability, achieving high tensile strain and high toughness.

[0066] 3. In the second half of the synthesis route of the present invention, a large number of double bonds and hydroxyl groups are introduced through acrylic acid in the ring-opening reaction, and then the esterification reaction of the hydroxyl group and the unsaturated acid anhydride is utilized. In some embodiments, the prepared alkali-soluble photocurable epoxy resin can have a higher double bond density and intermolecular force, and the cured film thereof has a high glass transition temperature and the ability to adhere to the substrate.

[0067] 4. The alkali-soluble photocurable epoxy resin prepared by the present invention has the ability of alkali elution, that is, it has alkali developability, and can be quickly and completely detached by directly soaking and washing in concentrated alkali solution without damaging the substrate.

[0068] 5. Comparative experimental characterization shows that the alkali-soluble photocurable epoxy resin prepared based on eugenol has excellent performance in mechanical properties, welding heat resistance, solvent resistance, dielectric properties, voltage breakdown resistance, chemical resistance, electroless gold plating resistance, electroless tin plating resistance, and electrical insulation properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of the dihydroxy compound modified with eugenol obtained in step (1) of Synthesis Example 1 of the present invention.

[0070] Figure 2 This is the hydrogen nuclear magnetic resonance spectrum of the dihydroxy compound modified with eugenol obtained in step (1) of Synthesis Example 2 of the present invention.

[0071] Figure 3 The hydrogen nuclear magnetic spectra of the intermediate products and the final products of Synthesis Examples 1 to 2 and Comparative Synthesis Example 1 of the present invention are shown in Figure (a) from top to bottom respectively, the hydrogen nuclear magnetic spectra of the vanillin-modified alkali-soluble photocurable epoxy resin (EAAT), the intermediate product acrylic acid-modified epoxy intermediate monomer (DGEVA / AA) and the intermediate product epoxy intermediate monomer (DGEVA) prepared in Comparative Synthesis Example 1; the hydrogen nuclear magnetic spectra of the eugenol-modified alkali-soluble photocurable epoxy resin (2-EMAT), the intermediate product acrylic acid-modified epoxy intermediate monomer (2-DGEEM / AA) and the intermediate product epoxy intermediate monomer (2-DGEEM) prepared in Synthesis Example 1; the hydrogen nuclear magnetic spectra of the eugenol-modified alkali-soluble photocurable epoxy resin (6-EMAT), the intermediate product acrylic acid-modified epoxy intermediate monomer (6-DGEEM / AA) and the intermediate product epoxy intermediate monomer (6-DGEEM) prepared in Synthesis Example 2 are shown in Figure (c) from top to bottom respectively.

[0072] Figure 4 The stress-strain curves and test photos of the cured film samples obtained in Application Examples 1 to 2 and Comparative Application Example 1 of the present invention. Figure (a) is a stress-strain curve of the comparative sample of the cured film obtained in Comparative Application Example 1, and the small figure is a photo of the stress-strain test; Figure (b) is a stress-strain curve of the cured film sample obtained in Application Example 1; Figure (c) is a stress-strain curve of the cured film sample obtained in Application Example 2.

[0073] Figure 5The figures are the dynamic mechanical thermal test results of the cured film samples obtained in Application Examples 1 to 2 and Comparative Application Example 1 of the present invention. Among them, Figure (a) is a comparison of the tan (δ) results of the cured film samples obtained in Application Examples 1 to 2 and Comparative Application Example 1, and Figure (b) is a comparison of the storage modulus results of the cured film samples obtained in Application Examples 1 to 2 and Comparative Application Example 1. In the figure, 6-EMAT corresponds to the cured film sample obtained in Application Example 2, 2-EMAT corresponds to the cured film sample obtained in Application Example 1, and EAAT corresponds to the cured film comparison sample obtained in Comparative Application Example 1.

[0074] Figure 6 This is a comparison chart of the DC voltage breakdown strength of the cured film samples obtained in Application Examples 1 to 2 of the present invention and Comparative Application Example 1. In the figure, 6-EMAT corresponds to the cured film sample obtained in Application Example 2, 2-EMAT corresponds to the cured film sample obtained in Application Example 1, and EAAT corresponds to the comparative cured film sample obtained in Comparative Application Example 1. DETAILED DESCRIPTION

[0075] In order to further understand the present invention, the preferred embodiments of the present invention are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the invention. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It is particularly important to point out that all similar substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments, and relevant personnel can obviously change or appropriately change and combine the methods and applications described herein without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention. Although it is believed that those of ordinary skill in the art fully understand the following terms, the following definitions are still stated to help illustrate the subject matter disclosed by the present invention.

[0076] In one aspect, the present invention provides a eugenol-modified alkali-soluble photocurable epoxy resin, the chemical structure of which is as follows:

[0077]

[0078] or:

[0079]

[0080] In the formula, R is any one of the following structures:

[0081]

[0082] In the above chemical structural formula, “…” indicates the position where the chemical bonds are connected.

[0083] On the other hand, the present invention also provides a method for preparing the above-mentioned eugenol-modified alkali-soluble photocurable epoxy resin, which is to first extend the chain of eugenol (CAS: 97-53-0) with mercaptoalkanol as a chain extender and introduce alcoholic hydroxyl groups, then perform an epoxidation reaction with epichlorohydrin to obtain an epoxy intermediate monomer, then perform a ring-opening polymerization reaction modification with acrylic acid, and finally perform an esterification reaction with an unsaturated acid anhydride to obtain the eugenol-modified alkali-soluble photocurable epoxy resin. It should be noted that those skilled in the art can obtain specific preparation steps according to the reaction sequence shown above, especially the ring-opening polymerization modification with acrylic acid and the esterification reaction with an unsaturated acid anhydride, which is a conventional synthetic route for preparing alkali-soluble photocurable epoxy resins in the art; therefore, the embodiments provided below by the present invention do not mean the sole designation or limitation of the preparation method of the eugenol-modified alkali-soluble photocurable epoxy resin.

[0084] In one preferred embodiment, the method for preparing the eugenol-modified alkali-soluble photocurable epoxy resin mainly comprises the following steps:

[0085] (1) in an air atmosphere, eugenol (EU), mercaptoalkanol and a photoinitiator for a thiol-ene click chemistry reaction are added to a reaction vessel, and the reaction is carried out for 12 to 24 hours with stirring under ultraviolet light irradiation at a photoinitiating wavelength of the photoinitiator for the thiol-ene click chemistry reaction to obtain a dihydroxy compound modified with eugenol;

[0086] Wherein, the mercaptoalkanol is an alkyl chain compound with a hydroxyl group at one end of the molecular structure and a mercapto group at the other end, and the molar ratio of the eugenol to the mercaptoalkanol is 1:(1-1.1);

[0087] (2) adding epichlorohydrin and an epoxidation catalyst to the dihydroxy compound modified with eugenol obtained in step (1), mixing and dissolving them thoroughly, stirring and reacting them at a temperature of 60 to 80° C. for 8 to 24 hours, and separating and obtaining an epoxy intermediate monomer;

[0088] The reaction is carried out at a temperature of 60 to 80° C. for 8 to 24 hours, and a ring-closing reaction is performed during the reaction, or a ring-closing reaction is performed after the reaction time is reached;

[0089] The molar ratio of the dihydroxy compound modified with eugenol to epichlorohydrin is 1:(5-12);

[0090] (3) In an air atmosphere, the epoxy intermediate monomer obtained in step (2), acrylic acid and a solvent are added to a reaction vessel, and a cyclic ester ring-opening polymerization catalyst and a polymerization inhibitor are added. After being fully mixed, the temperature is adjusted to 100 to 125° C. and stirred for reaction for 8 to 16 hours to obtain an acrylic acid-modified epoxy intermediate monomer;

[0091] (4) Cooling the acrylic acid-modified epoxy intermediate monomer obtained in step (3) to 70-80° C., then adding unsaturated acid anhydride, and continuing to stir and react at 85-100° C. for 6-12 hours to obtain a eugenol-modified alkali-soluble photocurable epoxy resin.

[0092] In this article, the "eugenol" (CAS: 97-53-0) described in step (1) is a lignin-derived structural monomer, which can be commercially available or homemade, and the purity requirement is usually chemical raw material grade.

[0093] In one embodiment, the mercaptoalkanol in step (1) is selected from at least one of mercaptomethanol, 2-mercaptoethanol, 3-mercaptopropanol, 4-mercaptobutanol, 5-mercaptopentanol, 6-mercaptohexanol, 7-mercaptoheptanol, 8-mercaptooctanol, 9-mercaptononanol, 10-mercaptodecanol, 11-mercaptoundecanol, 12-mercaptododecanol, 13-mercaptotridecanol, 14-mercaptotetradecanol, 15-mercaptopentadecanol, 16-mercaptohexadecanol, 17-mercaptoheptadecanol or 18-mercaptooctadecanol.

[0094] Herein, the photoinitiator for thiol-ene click chemistry reaction described in step (1) is a photoinitiator commonly used in the technical field for thiol-ene click chemistry reaction. Technicians in the technical field can select a suitable photoinitiator for thiol-ene click chemistry reaction according to actual needs, and determine the corresponding appropriate addition amount and optimal wavelength of ultraviolet light according to the existing technical information such as the commercial instructions / operation manual of the specifically selected thiol-ene click chemistry reaction photoinitiator.

[0095] In one embodiment, the photoinitiator for the thiol-ene click chemistry reaction in step (1) is selected from any one of 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methylpropiophenone, benzophenone, dibenzophenone, and (2,4,6-trimethylbenzoyl)diphenylphosphine oxide.

[0096] In order to better illustrate the present invention and provide an implementation method for reference, when the photoinitiator for the thiol-ene click chemistry reaction in step (1) is selected as 2-hydroxy-2-methylpropiophenone, ultraviolet light with a wavelength of 395 nm should be used for irradiation, and its addition amount is 2.5 to 3.5 wt % of the total mass of eugenol and mercaptoalkanol in step (1).

[0097] Herein, the catalyst for epoxidation reaction in step (2) is a catalyst commonly used for epoxidation reaction in the technical field, and technicians in the technical field can select a suitable catalyst for epoxidation reaction according to actual needs.

[0098] In one embodiment, the catalyst for the epoxidation reaction in step (2) is selected from any one of tetrabutylammonium bromide, tetramethylammonium bromide, and benzyltriethylammonium chloride; the amount of the catalyst added is 8 to 12% of the molar amount of the dihydroxy compound modified with eugenol in step (2).

[0099] Herein, the ring-closing reaction treatment in step (2) is a conventional process selection in the epoxidation reaction process. Those skilled in the art can directly select an appropriate method for the ring-closing reaction treatment based on the common knowledge of epoxidation reactions or conventional epoxidation reaction processes in the art.

[0100] In order to better illustrate the present invention and provide an embodiment for reference, the reaction described in step (2) is carried out at a temperature of 60 to 80° C. for 8 to 24 hours, and a ring-closing reaction is carried out during the reaction. Specifically, a NaOH aqueous solution having a mass of solute NaOH 3 to 5 times that of the dihydroxy compound and a mass concentration of 20 to 40 wt% is added to the reaction solution (the dihydroxy compound modified with eugenol, epichlorohydrin and the catalyst for the epoxidation reaction), and the reaction is carried out together at a temperature of 60 to 80° C. for 8 to 24 hours.

[0101] In order to better illustrate the present invention and provide an implementation method for reference, the reaction is carried out at a temperature of 60 to 80° C. for 8 to 24 hours in step (2), and a closed-loop reaction is carried out after the reaction time is reached. Specifically, after the reaction time is reached, after the product is cooled to room temperature, a NaOH aqueous solution having a mass of solute NaOH that is 3 to 5 times that of the dihydroxy compound and a mass concentration of 20 to 40 wt% is added under stirring, and stirring is continued for 15 hours.

[0102] In one embodiment, the epoxy intermediate monomer is separated in step (2). Since epichlorohydrin is used as both a reactant and a solvent, and the reaction product is also a liquid, rotary evaporation separation is preferably used.

[0103] It should be noted that the separation process in step (2) is usually accompanied by conventional process operations such as liquid separation and washing, which are common knowledge in the technical field and will not be described here.

[0104] Herein, the cyclic ester ring-opening polymerization catalyst in step (3) is a cyclic ester ring-opening polymerization catalyst commonly used in epoxy resin ring-opening polymerization reactions in the technical field. Those skilled in the art can select a suitable cyclic ester ring-opening polymerization catalyst according to actual needs.

[0105] In one embodiment, the cyclic ester ring-opening polymerization catalyst in step (3) is selected from one of triethylamine, triethanolamine, 4-dimethylaminopyridine, tetrabutylammonium bromide, tetramethylammonium chloride, N,N-dimethylbenzylamine and triphenylphosphine; the amount of the cyclic ester ring-opening polymerization catalyst added is 0.5 to 1.0 wt% of the total mass of the epoxy intermediate monomer and acrylic acid in step (3).

[0106] In this article, the solvent in step (3) is selected from conventional solvents in the art, and can be conventional solvents used in inks.

[0107] In one embodiment, the solvent selected in step (3) includes at least one of a dibasic acid ester high-boiling point environmentally friendly solvent, ethylene glycol ethyl ether acetate, ethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol butyl ether acetate, propylene glycol methyl ether acetate, propylene glycol methyl ether propionate, dipropylene glycol methyl ether, propylene glycol methyl ether, trimethylbenzene and tetramethylbenzene; the amount of solvent added can refer to the conventional amount used in the process for preparing alkali-soluble light-curing epoxy resin in the technical field of this invention, or refer to the following preferred embodiment: in step (1), solvent mass: epoxy intermediate monomer mass = (0.5-4): 1.

[0108] In this article, the polymerization inhibitor in step (3) is selected from conventional polymerization inhibitors in the art, and can be polymerization inhibitors conventionally used in ink technology.

[0109] In one embodiment, the polymerization inhibitor in step (3) is selected from at least one of hydroquinone, o-methyl hydroquinone, p-hydroxyanisole, p-benzoquinone and 2,6-di-tert-butyl-4-methylphenol. Preferably, the polymerization inhibitor added twice is the same polymerization inhibitor; the amount of the polymerization inhibitor added in step (3) is 0.3-1.0wt% of the total mass of the epoxy intermediate monomer and acrylic acid in step (3).

[0110] In this article, the amount of acrylic acid added in step (3) is preferably consistent with the amount of acrylic acid added in the conventional synthesis process for preparing alkali-soluble photocurable epoxy resins in the art, and is usually calculated based on the balanced molar amount of the chemical reaction formula. In one embodiment, for example, the molar ratio of the acrylic acid to the epoxy intermediate monomer is (2 to 2.1):1.

[0111] Herein, the unsaturated anhydride in step (4) is a conventional choice of unsaturated anhydride in the process of preparing alkali-soluble photocurable epoxy resin in the art. Those skilled in the art can directly select a suitable unsaturated anhydride from the relevant technical literature on preparing alkali-soluble photocurable epoxy resin in the prior art.

[0112] In this article, the amount of unsaturated anhydride added in step (4) is preferably consistent with the amount of unsaturated anhydride added in the conventional synthesis process for preparing alkali-soluble photocurable epoxy resin in the art, but it is also possible to choose to esterify with only half of the hydroxyl groups. In one embodiment, the molar ratio of the unsaturated anhydride to the molar ratio of the epoxy intermediate monomer is (1 to 2.1):1.

[0113] In one embodiment, the unsaturated acid anhydride in step (4) is selected from at least one of tetrahydrophthalic anhydride, itaconic anhydride, maleic anhydride, succinic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride and methylhexahydrophthalic anhydride.

[0114] Herein, the stirring reaction is a stirring reaction conventionally used in the art, including magnetic stirring or mechanical stirring, and those skilled in the art can select a suitable stirring reaction mode according to the production scale or the current process conditions. In one embodiment, the stirring reaction can be carried out at a stirring rate of 100 to 300 rpm.

[0115] On the other hand, based on the above-mentioned eugenol-modified alkali-soluble photocurable epoxy resin, the present invention also provides a high-performance photosensitive solder resist ink using the above-mentioned alkali-soluble photocurable epoxy resin as a main component, and its raw materials mainly include, by weight:

[0116] 100 parts of eugenol-modified alkali-soluble light-curing epoxy resin,

[0117] 1 to 5 parts of photoinitiator.

[0118] Herein, the photoinitiator is a photoinitiator conventionally selected for preparing photosensitive solder resist ink in the art, and those skilled in the art can select a suitable photoinitiator based on the current process conditions or existing technical literature in the art.

[0119] In one embodiment, the photoinitiator is preferably at least one of 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide, 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone, 2-hydroxy-4-(2-hydroxyethoxyphenyl)-2-methylpropiophenone, 2-isopropylthioxanthone (2,4 isomers), 2-hydroxy-2-methyl-1-phenylpropiophenone, 1-hydroxycyclohexylphenylmethanol, benzoin ethyl ether, benzil dimethyl ketal, 1-hydroxyphenylhexylacetophenone, benzophenone / triethanolamine and benzophenone / acrylate active amine.

[0120] In one preferred embodiment, the high performance photosensitive solder resist ink further comprises, by weight:

[0121] 20 to 50 parts of filler,

[0122] 1 to 25 parts of additives.

[0123] Among them, in order to improve the physical strength of the coating after the solder resist ink is used, the solder resist ink component includes a filler, and the filler is a well-known inorganic or organic filler. In one embodiment, one or more of titanium dioxide, bentonite, barium sulfate, spherical silica, nano-calcium carbonate, and talc are preferred. Furthermore, well-known metal oxides are preferably used as both fillers and pigments.

[0124] The additive is one or more combinations of pigments, thermal inhibitors, tackifiers, defoamers, leveling agents, coupling agents, antioxidants and rust inhibitors. Generally, the pigments, thermal inhibitors, tackifiers, defoamers, leveling agents, coupling agents, antioxidants and rust inhibitors are well known and commonly used.

[0125] The preparation method of the high-performance photosensitive solder resist ink can be prepared by mixing all components in accordance with the prior art. For example, the components are preliminarily mixed in a blender and then kneaded in a three-roll mill to obtain the high-performance photosensitive solder resist ink.

[0126] When the above solder resist ink is used, it is applied to the substrate, dried appropriately (about 60 to 90°C), and then exposed through a pattern film to obtain a cured coating film, and the unexposed portion is developed. When developing, the above solvent or a well-known halogen solvent such as trichloroethylene can be used for solvent development, but since carboxyl groups are introduced into the alkali-soluble photocurable epoxy resin modified with an acetylene-containing reactive monomer, the unexposed portion will dissolve in an alkaline aqueous solution, so alkaline development is preferably performed. For alkaline solvent development, alkali metal compounds such as sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, etc. can be selected; alkaline earth metal compounds such as calcium hydroxide can also be selected; alkaline solution ammonia water can also be selected; water-soluble organic amines such as monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monopropylamine, dipropylamine, dimethylpropylamine, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, dimethylaminoethyl methacrylate, polyethyleneimine, etc. can also be selected.

[0127] After development, it is preferred that a heat treatment be performed at about 120 to 160° C. for 1 hour to further heat cure the photocured coating film.

[0128] Generally, the high-performance photosensitive solder resist ink can be directly applied to a substrate in a liquid state or used in a state of a solder resist layer dry film formed by applying and drying on a film such as PET in advance.

[0129] The present invention will be further explained in detail with reference to the following examples. However, it should be understood by those skilled in the art that these examples are provided for illustrative purposes only and are not intended to limit the present invention.

[0130] Example

[0131] The embodiments of the present application will be described in detail below in conjunction with the examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. The specific conditions not specified in the examples are carried out according to the conditions recommended by normal conditions or manufacturers. The reagents used or the instruments not specified by the manufacturer are all conventional products that can be obtained commercially. The application should not be construed as being limited to the specific examples described.

[0132] 1. Raw materials

[0133] Eugenol (EU) and benzyltriethylammonium chloride (TEBAC) were provided by Shanghai Titan Technology Co., Ltd.;

[0134] 2-(2-ethoxyethoxy)ethyl acetate (DCAC), 2-mercaptoethanol (2-MCH), 6-mercaptohexanol (6-MCH), hydroquinone (HQ), and triphenylphosphine (TPP) were provided by Chengdu Huaxia Chemical Reagent Co., Ltd.;

[0135] Vanillyl alcohol (VA) was purchased from Shanghai MacLean Biochemical Technology Co., Ltd.;

[0136] Epichlorohydrin (ECH), sodium hydroxide (NaOH), and 2-hydroxy-2-methylpropiophenone (HMPP) were provided by Chengdu Kelong Chemical Co., Ltd.;

[0137] 2-Isopropylthioxanthone (photoinitiator ITX), acrylic acid (AA), and tetrahydrophthalic anhydride (THPA) were provided by Sinopharm Chemical Reagent Co., Ltd.;

[0138] Phthalocyanine green and pentaerythritol triacrylate (PETA) were produced by Aladdin Reagent (Shanghai) Co., Ltd.;

[0139] Epoxy-functionalized silica and barium sulfate nanoparticles were prepared by Shenzhen Haiyang Powder Technology Co., Ltd.;

[0140] Thermosetting epoxy resin (NC3000) was provided by Nippon Kayaku Co., Ltd.

[0141] Synthesis example 1

[0142] (1) In an air atmosphere, 32.8 g of eugenol (EU), 15.6 g of 2-mercaptoethanol (2-MCH) and 1.5 g of 2-hydroxy-2-methylpropiophenone (HMPP) were added to a reaction container, and the mixture was stirred for reaction for 15 h under irradiation with 395 nm ultraviolet light to obtain a dihydroxy compound modified with eugenol;

[0143] (2) adding 185.0 g of epichlorohydrin (ECH) and 4.5 g of benzyltriethylammonium chloride (TEBAC) to the dihydroxy compound modified with eugenol obtained in step (1), mixing and dissolving them thoroughly, and stirring and reacting at 80° C. for 15 h to obtain a pink solution;

[0144] After the pink solution was completely cooled at room temperature, 133 g of a 30 wt% aqueous NaOH solution was added, and stirring was continued for 15 h to obtain a mixed solution after the ring-closure reaction treatment;

[0145] The obtained mixed solution is separated to obtain an organic phase, which is then washed to neutrality, and then the solvent is removed by vacuum rotary evaporation to obtain an epoxy intermediate monomer;

[0146] (3) In an air atmosphere, 53.2 g of the epoxy intermediate monomer obtained in step (2), 21.6 g of acrylic acid and 24.9 g of 2-(2-ethoxyethoxy)ethyl acetate (DCAC) were added to a reaction container, and 0.6 g of triphenylphosphine (TPP) and 0.4 g of hydroquinone (HQ) were added. After being fully mixed, the temperature was adjusted to 105° C. and stirred for reaction for 12 hours to obtain an acrylic acid-modified epoxy intermediate monomer.

[0147] (4) The acrylic acid-modified epoxy intermediate monomer obtained in step (3) was cooled to 70° C., and then 22.8 g of tetrahydrophthalic anhydride (THPA) was added, and the mixture was stirred and reacted at 95° C. for 6 hours to obtain a eugenol-modified alkali-soluble photocurable epoxy resin.

[0148] Synthesis example 2

[0149] (1) In an air atmosphere, 32.8 g of eugenol (EU), 26.8 g of 6-mercaptoethanol (6-MCH) and 1.8 g of 2-hydroxy-2-methylpropiophenone (HMPP) were added to a reaction container, and the mixture was stirred for reaction for 20 h under irradiation with 395 nm ultraviolet light to obtain a dihydroxy compound modified with eugenol;

[0150] (2) adding 185.0 g of epichlorohydrin (ECH) and 4.5 g of benzyltriethylammonium chloride (TEBAC) to the dihydroxy compound modified with eugenol obtained in step (1), mixing and dissolving them thoroughly, and stirring and reacting at 80° C. for 20 h to obtain a pink solution;

[0151] Then, after the pink solution was completely cooled at room temperature, 133 g of a 30 wt% aqueous NaOH solution was added, and stirring was continued for 20 h to obtain a mixed solution after the ring-closure reaction treatment;

[0152] The obtained mixed solution is separated to obtain an organic phase, which is then washed to neutrality, and then the solvent is removed by vacuum rotary evaporation to obtain an epoxy intermediate monomer;

[0153] (3) In an air atmosphere, 61.6 g of the epoxy intermediate monomer obtained in step (2), 21.6 g of acrylic acid and 27.7 g of 2-(2-ethoxyethoxy)ethyl acetate (DCAC) were added to a reaction container, and 0.7 g of triphenylphosphine (TPP) and 0.4 g of hydroquinone (HQ) were added. After being fully mixed, the temperature was adjusted to 105° C. and the reaction was stirred for 12 hours to obtain an acrylic acid-modified epoxy intermediate monomer.

[0154] (4) The acrylic acid-modified epoxy intermediate monomer obtained in step (3) was cooled to 70° C., and then 22.8 g of tetrahydrophthalic anhydride (THPA) was added, and the mixture was stirred and reacted at 95° C. for 6 hours to obtain a eugenol-modified alkali-soluble photocurable epoxy resin.

[0155] Comparative Synthesis Example 1

[0156] (1) In an air atmosphere, 46.2 g of vanillyl alcohol (VA), 277.6 g of epichlorohydrin (ECH) and 6.8 g of benzyltriethylammonium chloride (TEBAC) were added to a reaction vessel, mixed and dissolved thoroughly, and stirred at 80° C. for 8 h to obtain a pink solution;

[0157] Then, after the pink solution was completely cooled at room temperature, 133 g of a 30 wt% aqueous NaOH solution was added, and stirring was continued for 12 h to obtain a mixed solution after the ring-closure reaction treatment;

[0158] The obtained mixed solution is separated to obtain an organic phase, which is then washed to neutrality, and then the solvent is removed by vacuum rotary evaporation to obtain an epoxy intermediate monomer;

[0159] (3) In an air atmosphere, 40.0 g of the epoxy intermediate monomer obtained in step (2), 21.6 g of acrylic acid and 20.5 g of 2-(2-ethoxyethoxy)ethyl acetate (DCAC) were added to a reaction container, and 0.5 g of triphenylphosphine (TPP) and 0.3 g of hydroquinone (HQ) were added. After being fully mixed, the temperature was adjusted to 105° C. and stirred for reaction for 12 hours to obtain an acrylic acid-modified epoxy intermediate monomer.

[0160] (4) The acrylic acid-modified epoxy intermediate monomer obtained in step (3) is cooled to 70° C., and then 22.8 g of tetrahydrophthalic anhydride (THPA) is added, and the reaction is continued at 95° C. with stirring for 6 hours to obtain a vanillyl alcohol-modified alkali-soluble photocurable epoxy resin.

[0161] Application Example 1

[0162] The eugenol-modified alkali-soluble photocurable epoxy resin prepared in Synthesis Example 1 was used as a raw material, and the following raw materials were prepared in parts by weight:

[0163] 100 parts of eugenol-modified alkali-soluble light-curing epoxy resin,

[0164] Photoinitiator ITX 3 parts;

[0165] After the components of the prepared materials are preliminarily mixed in a blender, they are kneaded with a three-roll mill to obtain a high-performance photosensitive solder resist ink.

[0166] The obtained high-performance photosensitive solder resist ink is then coated on a substrate, dried at 75° C. for 30 minutes for curing, and finally the cured film formed after curing is used as a sample for testing.

[0167] Application Example 2

[0168] The eugenol-modified alkali-soluble photocurable epoxy resin prepared in Synthesis Example 2 was used as a raw material, and the following raw materials were prepared in parts by weight:

[0169] 100 parts of eugenol-modified alkali-soluble light-curing epoxy resin,

[0170] Photoinitiator ITX 3 parts;

[0171] After the components of the prepared materials are preliminarily mixed in a blender, they are kneaded with a three-roll mill to obtain a high-performance photosensitive solder resist ink.

[0172] The obtained high-performance photosensitive solder resist ink is then coated on a substrate, dried at 75° C. for 30 minutes for curing, and finally the cured film formed after curing is used as a sample for testing.

[0173] Comparative application example 1

[0174] The vanillin alcohol-modified alkali-soluble photocurable epoxy resin prepared in Comparative Synthesis Example 1 was used as a raw material, and the following raw materials were prepared in parts by weight:

[0175] 100 parts of vanillin alcohol modified alkali soluble light curing epoxy resin,

[0176] Photoinitiator ITX 3 parts;

[0177] After the components of the prepared materials are preliminarily mixed in a blender, they are kneaded using a three-roll mill to obtain a photosensitive solder resist contrast ink.

[0178] The obtained photosensitive solder resist contrast ink was then coated on a substrate and dried at 75° C. for 30 minutes for curing. Finally, the cured film formed after curing was used as a contrast sample for testing.

[0179] Application Example 3

[0180] The eugenol-modified alkali-soluble photocurable epoxy resin prepared in Synthesis Example 1 was used as a raw material, and the following raw materials were prepared in parts by weight:

[0181]

[0182]

[0183] After the components of the prepared materials are preliminarily mixed in a blender, they are kneaded with a three-roll mill to obtain a high-performance photosensitive solder resist ink.

[0184] 3. Test Methods

[0185] (1) Infrared test: The infrared spectrum (FT-IR) test was measured using a Nicolet is50 Fourier transform infrared spectrometer with a resolution of 4 cm -1 , scanning range is 400-4000cm -1 Among them, the solid sample is measured by potassium bromide tablet method, and the liquid sample is measured by smearing method on potassium bromide tablet.

[0186] (2) Nuclear magnetic resonance spectroscopy test: The nuclear magnetic resonance spectroscopy test was performed using tetramethylsilane (TMS) as the internal standard and a Bruker AV-400 spectrometer. 1 For H NMR analysis, the test sample concentration was 10 mg / ml.

[0187] (3) Stress-strain test: Dynamic mechanical thermal analyzer (DMTA, TA Instruments Q850) was used to obtain the stress-strain curve of the cured film. The stress-strain test was carried out at a constant temperature of 25°C and a speed of 0.2 Nmin. -1 The mechanical properties of the samples were measured at room temperature, and the sample size was 30mm×3mm×0.05mm.

[0188] (4) Dynamic mechanical thermal test: Dynamic mechanical thermal analyzer (DMTA, TA Instruments Q850) has thermal characteristics. -1 The temperature stability of the sample was measured in the controlled force mode, the temperature range was 25-150°C, and the sample size was 30mm×3mm×0.05mm.

[0189] (5) Electrical breakdown strength: recorded by a breakdown voltage meter (Beijing Guance Precision Instrument Equipment Co., Ltd.), with a maximum electric field of 100 kV.

[0190] The test results are as attached Figures 1 to 6 shown.

[0191] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A eugenol-modified alkali-soluble photocurable epoxy resin, characterized in that The chemical structure is as follows: or: In the formula, R is any one of the following structures:

2. A method for preparing a eugenol-modified alkali-soluble photocurable epoxy resin, characterized in that The main steps include: (1) adding eugenol, mercaptoalkanol and a photoinitiator for thiol-ene click chemistry reaction into a reaction vessel under air atmosphere, and reacting for 12 to 24 hours with stirring under ultraviolet light irradiation of a photoinitiating wavelength of the photoinitiator for thiol-ene click chemistry reaction to obtain a dihydroxy compound modified with eugenol; Wherein, the mercaptoalkanol is an alkyl chain compound with a hydroxyl group at one end of the molecular structure and a mercapto group at the other end, and the molar ratio of the eugenol to the mercaptoalkanol is 1:(1-1.1); (2) adding epichlorohydrin and an epoxidation catalyst to the dihydroxy compound modified with eugenol obtained in step (1), mixing and dissolving them thoroughly, stirring and reacting them at a temperature of 60 to 80° C. for 8 to 24 hours, and separating and obtaining an epoxy intermediate monomer; The reaction is carried out at a temperature of 60 to 80° C. for 8 to 24 hours, and a ring-closing reaction is performed during the reaction, or a ring-closing reaction is performed after the reaction time is reached; The molar ratio of the eugenol-modified dihydroxy compound to epichlorohydrin is 1:(5-12); (3) In an air atmosphere, the epoxy intermediate monomer obtained in step (2), acrylic acid and a solvent are added to a reaction vessel, and a cyclic ester ring-opening polymerization catalyst and a polymerization inhibitor are added. After being fully mixed, the temperature is adjusted to 100 to 125° C. and stirred for reaction for 8 to 16 hours to obtain an acrylic acid-modified epoxy intermediate monomer; (4) Cooling the acrylic acid-modified epoxy intermediate monomer obtained in step (3) to 70-80° C., then adding unsaturated acid anhydride, and continuing to stir and react at 85-100° C. for 6-12 hours to obtain a eugenol-modified alkali-soluble photocurable epoxy resin.

3. The preparation method according to claim 2, characterized in that: The mercaptoalkanol described in step (1) includes at least one of mercaptomethanol, 2-mercaptoethanol, 3-mercaptopropanol, 4-mercaptobutanol, 5-mercaptopentanol, 6-mercaptohexanol, 7-mercaptoheptanol, 8-mercaptooctanol, 9-mercaptononanol, 10-mercaptodecanol, 11-mercaptoundecanol, 12-mercaptododecanol, 13-mercaptotridecanol, 14-mercaptotetradecanol, 15-mercaptopentadecanol, 16-mercaptohexadecanol, 17-mercaptoheptadecanol or 18-mercaptooctadecyl alcohol.

4. The preparation method according to claim 2, characterized in that: The photoinitiator for the thiol-ene click chemistry reaction in step (1) is selected from any one of 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methylpropiophenone, benzophenone, dibenzophenone, and (2,4,6-trimethylbenzoyl)diphenylphosphine oxide.

5. The preparation method according to claim 2, characterized in that: The catalyst for the epoxidation reaction in step (2) includes any one of tetrabutylammonium bromide, tetramethylammonium bromide, and benzyltriethylammonium chloride; the amount of the catalyst added is 8 to 12% of the molar amount of the dihydroxy compound modified with eugenol in step (2).

6. The preparation method according to claim 2, characterized in that: The step (2) is reacted at 60-80° C. for 8-24 hours, and a ring-closing reaction is performed during the reaction. Specifically, a NaOH aqueous solution having a mass of 3-5 times that of the dihydroxy compound and a mass concentration of 20-40 wt% is added to the reaction solution, and the reaction is carried out at 60-80° C. for 8-24 hours. Or for, The step (2) is to react at a temperature of 60 to 80° C. for 8 to 24 hours, and then perform a ring-closing reaction after the reaction time is reached. Specifically, after the reaction time is reached, after the product is cooled to room temperature, a NaOH aqueous solution having a mass of solute NaOH that is 3 to 5 times that of the dihydroxy compound and a mass concentration of 20 to 40 wt% is added under stirring, and stirring is continued for 15 hours.

7. The preparation method according to claim 2, characterized in that: The unsaturated acid anhydride in step (4) includes at least one of tetrahydrophthalic anhydride, itaconic anhydride, maleic anhydride, succinic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride and methylhexahydrophthalic anhydride.

8. The preparation method according to claim 2, characterized in that: In step (4), the molar ratio of the unsaturated acid anhydride to the epoxy intermediate monomer is (1-2.1):

1.

9. A high-performance photosensitive solder resist ink using the eugenol-modified alkali-soluble photocurable epoxy resin as a main component, characterized in that The raw materials mainly include: 100 parts of eugenol-modified alkali-soluble light-curing epoxy resin, 1 to 5 parts of photoinitiator.

10. The high performance photosensitive solder resist ink according to claim 9, characterized in that: The raw materials include by weight: 20 to 50 parts of filler, 1 to 25 parts of additives.

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