Use of tetragonal aliphatic cyclic epoxy compounds in preparation of dry film for solder resist

Abstract

The application discloses application of a tetrafunctional alicyclic epoxy compound in preparation of a dry film for solder resist, and a structural formula of the tetrafunctional alicyclic epoxy compound is shown as formula (I). The tetrafunctional alicyclic epoxy compound of the application is easy to react with an alkali-soluble group of an alkali-soluble resin through an epoxy group in the structure, the degree of thermal curing is high, a network structure is formed, the performance of the dry film for solder resist is improved, the tetrafunctional alicyclic epoxy compound can be used as a raw material for preparing a resin composition for the dry film for solder resist and is coated on an electronic component, and the tetrafunctional alicyclic epoxy compound can also be used for UV packaging and coating protection of optical display, electronic manufacturing, flat panel and flexible display devices.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photocuring materials, and particularly relates to application of a tetrafunctional alicyclic epoxy compound in preparation of a solder resist dry film. BACKGROUND

[0002] The solder resist dry film is an important component of a printed circuit board, which is attached to a circuit substrate to form a solder resist layer, and insulates the circuit lines on the printed circuit board, thereby preventing short circuit and ensuring the integrity of electrical connection. The solder resist dry film is attached to a PCB, and then exposed, developed and post-baked and heat-cured through a mask plate with patterns. The purpose of post-baking and heat-curing is to further crosslink the carboxyl and epoxy groups in the dry film after photocuring, so as to improve the thermal and mechanical properties of the solder resist dry film, so that it can withstand various harsh conditions in the PCB manufacturing process, including thermal cycling, chemical exposure and mechanical stress.

[0003] The solder resist dry film generally contains an alkali-soluble photosensitive resin and a heat-curing resin. The double bond of the alkali-soluble photosensitive resin is crosslinked during photocuring, and the carboxyl group reacts with the epoxy group of the heat-curing resin. The traditional heat-curing resin is generally bisphenol A type epoxy resin, phenolic epoxy resin and biphenyl type and epoxy resin containing naphthalene ring structure, but its reactivity with the carboxyl group on the resin is low, the crosslinking reaction is slow and incomplete, while the reaction activity energy of the alicyclic epoxy resin with the carboxyl group is low, and it is more prone to react with the carboxyl group. At the same time, the rigid structure of the alicyclic ring and the high crosslinking density of the cured product make it have good adhesion strength to different substrates, high thermal deformation temperature, excellent chemical resistance and mechanical and electrical properties. However, the functional groups of the multi-functional alicyclic epoxy resin in the prior art are low or the steric hindrance of the epoxy groups is large, resulting in low heat curing degree. Therefore, it is necessary to find a multi-functional alicyclic epoxy resin that can be used to prepare a solder resist dry film. SUMMARY

[0004] A first object of the present application is to provide application of a tetrafunctional alicyclic epoxy compound in preparation of a solder resist dry film, so as to solve at least one of the above technical problems.

[0005] In a first aspect, the application provides application of a tetrafunctional alicyclic epoxy compound in preparation of a solder resist dry film, and the structural formula of the tetrafunctional alicyclic epoxy compound is shown as formula (I):

[0006]

[0007] The tetra-functional alicyclic epoxy compound has an alicyclic ring and an epoxy group, and when the epoxy group reacts with a carboxyl group, the functionality of the tetra-functional alicyclic epoxy compound is 4, the functionality is high, and the structure of the tetra-functional alicyclic epoxy compound makes the influence of the steric hindrance effect on the epoxy group smaller, so that the epoxy group of the tetra-functional alicyclic epoxy compound is easy to react with the carboxyl group of the alkali-soluble group during thermal curing of the solder resist dry film, which is beneficial to the crosslinking of the resin during thermal curing, the degree of thermal curing is high, and the tetra-functional alicyclic epoxy compound can be used for preparing the solder resist dry film. The tetra-functional alicyclic epoxy compound reacts with the carboxyl group of the alkali-soluble resin during thermal curing of the solder resist dry film, a complex network structure is formed, and the performance of the solder resist dry film can be improved.

[0008] In some embodiments, the solder resist dry film prepared from the tetra-functional alicyclic epoxy compound is used for UV packaging and coating protection in at least one aspect of optical display, electronic manufacturing, flat panel and flexible display device. Specifically, the tetra-functional alicyclic epoxy compound can be used as a solder resist dry film resin composition prepared from a thermosetting resin, and the solder resist dry film after curing into a film can be used for UV packaging and coating protection of optical display, electronic manufacturing, flat panel and flexible display device.

[0009] In some embodiments, the application of the tetra-functional alicyclic epoxy compound in the solder resist dry film is the application of the tetra-functional alicyclic epoxy compound in the preparation of a solder resist dry film resin composition, and the solder resist dry film resin composition comprises, in mass percentage, 45% to 55% of an alkali-soluble resin, 10% to 15% of a photosensitive monomer, 3% to 4% of a photoinitiator, 15% to 20% of the tetra-functional alicyclic epoxy compound, 0.5% to 1.5% of a thermal curing catalyst, 0.5% to 1.5% of an antifoaming agent, 0.5% to 1.5% of a leveling agent and 15% to 20% of a solvent.

[0010] The solder resist dry film resin composition of the present application, after the preparation of a photosensitive dry film, film pasting, exposure, development, drying, the solder resist dry film obtained, after a plurality of performance tests, it is found that the photosensitivity, resolution and mechanical properties of the solder resist dry film resin composition of the present application after curing into a solder resist dry film are good, and the solder resist dry film resin composition also has good flexibility and hardness.

[0011] In some embodiments, the photosensitive monomer is pentaerythritol triacrylate, the photoinitiator is diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO), the thermal curing catalyst is 2-methyl imidazole, the leveling agent is polyacrylate, the antifoaming agent is a silicone ether copolymer antifoaming agent, and the solvent is acetone.

[0012] In some embodiments, the molecular structure of the alkali-soluble resin contains at least one of a carboxyl group and a sulfonic acid group, the weight average molecular weight of the alkali-soluble resin is 6000 to 9000, and the acid value of the alkali-soluble resin is 40 to 120 mgKOH / g.

[0013] In some embodiments, the alkali-soluble resin can be prepared by a preparation method comprising the following steps: glycidyl methacrylate self-polymerization, addition of acrylic acid for grafting the acrylic structure by reaction with the epoxy group, and addition of succinic anhydride for terminal grafting of carboxyl groups. The mass ratio of glycidyl methacrylate: acrylic acid: succinic anhydride is 100:50:7, and the solvent is propylene glycol monomethyl ether acetate.

[0014] In some embodiments, the method for using the dry film solder resist composition comprises the following steps:

[0015] coating the dry film solder resist composition on the surface of a PET support film with a coating machine to obtain a photosensitive layer with a thickness of 20-30 μm, and covering the surface of the photosensitive layer with a PE protective film with a thickness of 20-30 μm;

[0016] peeling off the PE protective film, adhering the dry film solder resist composition to the surface of an electronic component, baking at 90-110°C for 3-10 min, then standing for 10-20 min, then exposing the circuit board to light with a wavelength of 300-400 nm, then standing for 15-30 min, peeling off the PET support film, developing the electronic component, then washing the electronic component with water and drying, to obtain a dry film solder resist adhered to the electronic component.

[0017] In some embodiments, the preparation method of the tetraalkylcycloaliphatic epoxy compound comprises the following steps:

[0018] S1, mixing pentaerythritol, 3-cyclohexene-1-carboxylic acid, a catalyst, and an organic solvent to obtain a solid-liquid mixture, dissolving a condensation agent in an organic solvent to obtain a first mixture, adding the first mixture dropwise to the solid-liquid mixture and stirring until the solids in the solid-liquid mixture are dissolved in the organic solvent, then reacting for 16-24 h, washing and drying the reaction system after the reaction to obtain an organic phase, then subjecting the organic phase to reduced pressure distillation, and subjecting the residue of the organic phase after reduced pressure distillation to crystallization to obtain pentaerythritol tetracyclohexene carboxylate;

[0019] S2, dissolving the pentaerythritol tetracyclohexene carboxylate in an organic solvent to obtain a second mixture, dissolving meta-chloroperoxybenzoic acid in an organic solvent to obtain a third mixture, then adding the third mixture dropwise to the second mixture under ice bath conditions, stirring and reacting for 16-24 h, filtering, purifying the filtrate after filtration to obtain an organic phase, and crystallizing to obtain the product.

[0020] The catalyst can be selected from at least one of 4-dimethylaminopyridine (DMAP), 1-hydroxybenzotriazole (HOBt), 4-pyrrolidinopyridine (4-PPY), and the condensing agent can be selected from at least one of N,N-dicyclohexyl carbodiimide (DCC), N,N-diisopropyl carbodiimide (DIC), 1-(3-dimethylaminopropyl)-3-ethyl carbodiimide (EDCI).

[0021] The preparation method of the tetraalkylcycloaliphatic epoxy compound of the present application is as follows: pentaerythritol and 3-cyclohexene-1-carboxylic acid are first subjected to Steglich esterification in an organic solvent to obtain pentaerythritol tetracyclohexene carboxylate, and then the pentaerythritol tetracyclohexene carboxylate is subjected to epoxidation by means of meta-chloroperoxybenzoic acid to obtain the tetraalkylcycloaliphatic epoxy compound.

[0022] In some embodiments, the molar ratio of pentaerythritol, 3-cyclohexene-1-carboxylic acid, catalyst and condensing agent is 1:(4-4.12):(1-1.10):(4-4.10).

[0023] In some embodiments, the amount of catalyst used can be 8-10% of the total mass of pentaerythritol, 3-cyclohexene-1-carboxylic acid and condensing agent.

[0024] In some embodiments, the amount of catalyst used can be 8-9% of the total mass of pentaerythritol, 3-cyclohexene-1-carboxylic acid and condensing agent.

[0025] In some embodiments, the amount of catalyst used can be 8.5% of the total mass of pentaerythritol, 3-cyclohexene-1-carboxylic acid and condensing agent.

[0026] In some embodiments, the organic solvent can be selected from at least one of tetrahydrofuran and dichloromethane.

[0027] In some embodiments, the amount of organic solvent used in step S1 can be 4-6 times the total mass of pentaerythritol, 3-cyclohexene-1-carboxylic acid and condensing agent.

[0028] In some embodiments, the volume of organic solvent required to dissolve the condensing agent in the first mixed solution can be 350-450 mL.

[0029] It should be noted that in the present application, the purpose of adding the organic solvent to the solid-liquid mixture and the first mixed solution is to dissolve pentaerythritol and the condensing agent in the organic solvent, and the organic solvent does not participate in the reaction, so the amount of the above-mentioned organic solvent is only one option and cannot be a limitation of the present application.

[0030] In some embodiments, the amount of organic solvent used in step S2 can be 10 times the mass of meta-chloroperoxybenzoic acid.

[0031] In some embodiments, the solvent volume of the organic solvent required for dissolving pentaerythritol tetracyclohexene carboxylate in the second mixed solution can be 50-70 mL.

[0032] In some embodiments, the solvent volume of the organic solvent required for dissolving m-chloroperbenzoic acid in the third mixed solution can be 180-220 mL.

[0033] It should be noted that the purpose of using the organic solvent in the second mixed solution and the third mixed solution in the present application is to dissolve m-chloroperbenzoic acid, and the amount of the above-mentioned organic solvent is only one option and cannot be regarded as a limitation of the present application.

[0034] In some embodiments, the molar ratio of pentaerythritol tetracyclohexene carboxylate to m-chloroperbenzoic acid can be 1:(4-4.10).

[0035] In some embodiments, the stirring and reaction time in step S1 can be 18 h.

[0036] In some embodiments, the treatment method of washing in step S1 can be transferring the reaction system after reaction to a separatory funnel, washing 3 times with a 1% hydrochloric acid solution, washing 3 times with a saturated sodium bicarbonate solution, and finally washing 3 times with a saturated sodium chloride solution to obtain the lower organic phase by separation. Specifically, the hydrochloric acid and the catalyst can be combined into a water-soluble salt, and the excess catalyst in the reaction system is removed after washing; the saturated sodium bicarbonate solution is used to remove the organic acid and hydrochloric acid, and to adjust the pH of the reaction system to neutral; and the saturated sodium chloride solution is used to remove the water-soluble impurities in the organic phase.

[0037] In other embodiments, the treatment method of washing in step S1 can be transferring the reaction system after reaction to a separatory funnel, washing 3 times with a 1% hydrochloric acid solution, and then washing 3 times with a saturated sodium chloride solution to obtain the lower organic phase by separation.

[0038] In other embodiments, the treatment method of washing in step S1 can be transferring the reaction system after reaction to a separatory funnel, washing the organic phase 3 times with a 1% hydrochloric acid solution, and then obtaining the lower organic phase by separation.

[0039] In some embodiments, the treatment method of drying in step S1 can be adding a solid drying agent to the reaction system after washing, and filtering and retaining the organic phase obtained after filtration.

[0040] In some embodiments, the solid drying agent can be selected from at least one of anhydrous sodium sulfate or anhydrous magnesium sulfate.

[0041] In some embodiments, in step S1, the conditions of the reduced pressure distillation can be that the filtered organic phase is subjected to reduced pressure distillation under a vacuum degree of -0.098 MPa and a water bath temperature of 30-40 DEG C for 1-3 h.

[0042] In some embodiments, in step S2, the purification treatment method can be that the filtrate is first dripped with saturated sodium sulfite solution, then washed with saturated sodium bicarbonate solution and saturated sodium chloride solution for 3 times respectively, the lower organic phase is obtained by liquid separation, solid drying agent is added to the washed organic phase, filtration is performed, and then the organic solvent in the organic phase is removed by reduced pressure distillation.

[0043] In some embodiments, in step S2, the conditions of the reduced pressure distillation for removing the organic solvent in the organic phase can be that the filtered organic phase is subjected to reduced pressure distillation under a vacuum degree of -0.098 MPa and a water bath temperature of 30-40 DEG C for 1-3 h.

[0044] In some embodiments, in step S2, the stirring and reaction time can be 18 h.

[0045] In some embodiments, in step S2, the purification treatment method can be that the organic phase is further purified by column chromatography after the reduced pressure distillation.

[0046] In some embodiments, the eluent used in the column chromatography can be a mixed liquid of petroleum ether and ethyl acetate, and the chromatographic column used in the column chromatography can be a silica gel column. The volume ratio of petroleum ether to ethyl acetate in the mixed liquid can be (6-9):1.

[0047] The present application has the following advantages:

[0048] In the present application, the tetra-functional alicyclic epoxy compound is used as a raw material for the dry film resist, and the tetra-functional alicyclic epoxy compound has 4 epoxy groups and an alicyclic structure. The epoxy groups of the tetra-functional alicyclic epoxy compound are easy to react with the carboxyl groups of the alkali-soluble groups during the thermal curing of the dry film resist, and the degree of thermal curing is high.

[0049] The tetra-functional alicyclic epoxy compound in the present application reacts with the alkali-soluble resin in the dry film resist to form a network structure, thereby improving the performance of the dry film resist. Performance tests show that the dry film resist prepared by using the tetra-functional alicyclic epoxy compound not only has good photosensitivity, resolution and mechanical properties, but also has good flexibility and hardness, and can be coated on electronic components and used for UV packaging and coating protection of optical display, electronic manufacturing, flat panel and flexible display devices. Attached Figure Description

[0050] Figure 1 The infrared spectra of 3-cyclohexene-1-carboxylic acid, intermediate product and product in Example 1 of the present invention are shown.

[0051] Figure 2 The images show the hydrogen nuclear magnetic resonance spectra of the intermediate and product of Example 1 of this invention. Detailed Implementation

[0052] The present invention will now be described in further detail with reference to the accompanying drawings, but the embodiments of the present invention are not limited thereto. The raw materials and reagents involved in the following embodiments are all commercially available.

[0053] Example 1

[0054] 6.8 g pentaerythritol (0.05 mol), 25.23 g 3-cyclohexene-1-carboxylic acid (0.2 mol), 6.13 g DMAP (0.05 mol), and dichloromethane were added sequentially to a 500 mL three-necked flask to obtain a solid-liquid mixture. 40.02 g EDCI (0.2 mol) was dissolved in dichloromethane to obtain a first mixture. The first mixture was then added dropwise to the solid-liquid mixture. After the addition was complete, the mixture was stirred at room temperature until the solid in the solid-liquid mixture was observed to dissolve in the organic solution. The reaction was allowed to proceed for 18 h. The reaction mixture was then transferred to a separatory funnel and diluted with dichloromethane, first with 1% hydrochloric acid. The solution was washed three times, then washed three times each with saturated sodium bicarbonate solution and saturated sodium chloride solution, respectively. The lower organic phase was obtained by separation. The organic phase was dried with anhydrous sodium sulfate and filtered. It was then subjected to vacuum distillation for 2 hours at -0.098 MPa and a water bath temperature of 30–40 °C to remove dichloromethane and trace amounts of water. Column chromatography was then performed using a silica gel column (eluent: a mixture of petroleum ether and ethyl acetate, volume ratio 7:1) to obtain a colorless, viscous liquid. After crystallization, a white crystalline intermediate was obtained. The yield of the intermediate was calculated to be 92.02%.

[0055] A 500 mL three-necked flask was charged with dichloromethane, and 5.68 g of the intermediate product (0.01 mol) was weighed into the flask. The intermediate product was slowly added dropwise to the flask with m-chloroperbenzoic acid (6.88 g, 0.04 mol) dissolved in dichloromethane under ice-bath conditions, and then the reaction was stirred at room temperature for 18 h. The intermediate product was removed by filtration, and the filtered filtrate was first washed with saturated sodium sulfite solution to remove excess m-chloroperbenzoic acid, and then washed with saturated sodium bicarbonate solution and saturated brine solution three times, respectively, to obtain the lower organic phase. The organic phase was dried with anhydrous magnesium sulfate and filtered to obtain the organic phase. The dichloromethane and a small amount of water in the organic phase were removed by vacuum distillation under a vacuum degree of -0.098 MPa and a water bath temperature of 30-40 °C for 2 h, and then column chromatography was performed on a silica gel column (eluent: a mixture of petroleum ether and ethyl acetate with a volume ratio of 7:1) to obtain a colorless viscous liquid. The colorless viscous liquid was allowed to crystallize to obtain the product in the form of white crystals. It was calculated that the yield of the product obtained by epoxidation of the intermediate product was 91%.

[0056] The structures of the intermediate product and the product were confirmed by Fourier transform infrared spectroscopy (FT-IR) and hydrogen nuclear magnetic resonance (H-NMR) analysis, respectively. FT-IR analysis was performed on 3-cyclohexene-1-carboxylic acid, the intermediate product, and the product, respectively, and the results are shown in FIG. 1. Figure 1 H-NMR analysis was performed on the intermediate product and the product, respectively, and the results are shown in FIG. 2. Figure 2

[0057] As can be seen from FIG. 1, Figure 1 the infrared spectrum of 3-cyclohexene-1-carboxylic acid can observe a strong and broad -COOH stretching vibration peak between 3500 and 3000 cm -1 -1. In the infrared spectrum of the intermediate product, the stretching vibration peak at 3031 cm -1 is attributed to C=C-H, and there is a clear C=O characteristic absorption peak at 1739 cm -1 , and there is no -OH stretching vibration peak at 3500 cm -1 belonging to pentaerythritol, indicating that the four hydroxyl groups of pentaerythritol are successfully synthesized into pentaerythritol tetracyclohexene carboxylate through esterification with 3-cyclohexene-1-carboxylic acid. In the infrared spectrum of the product, an absorption peak attributed to C-O-C appears at 797 cm -1 , and the C=C-H stretching vibration peak at 3031 cm -1 disappears, indicating that the double bond of pentaerythritol tetracyclohexene carboxylate disappears under the oxidation of m-chloroperbenzoic acid to generate a product with an epoxidized structure, indicating the successful synthesis of the tetraaliphatic epoxide product.

[0058] As can be seen from FIG. 2, Figure 2 ​It can be seen that the chemical shifts of the intermediate product (pentaerythritol tetracyclohexene formate) are: 1H NMR (600 MHz, Chloroform-d) δ 5.68 (s, 8H), 4.18-4.12 (m, 8H), 2.62-2.55 (m, 4H), 2.28-2.20 (m, 8H), 2.13-2.05 (m, 8H), 2.01-1.94 (m, 4H), 1.68 (dddd, J = 13.0, 11.2, 9.1, 6.8 Hz, 4H); and the chemical shifts of the product (tetraalicyclic ring epoxy compound) are: 1H NMR (600 MHz, Chloroform-d) δ 4.21-4.01 (m, 8H), 3.20 (ddd, J = 57.2, 5.5, 3.2 Hz, 8H), 2.58-2.47 (m, 2H), 2.32-1.53 (m, 26H). By comparing the 1H NMR spectra of the intermediate product and the product, it can be found that the characteristic peak at 5.68 ppm in the pentaerythritol tetracyclohexene formate, which is attributed to the double bond on the six-membered ring of 3-cyclohexene-1-formic acid, disappears in the spectrum of the tetraalicyclic ring epoxy compound, and two new characteristic peaks at 3.24-3.15 ppm in the tetraalicyclic ring epoxy compound, which are attributed to the epoxy group, further indicate the successful synthesis of the tetraalicyclic ring epoxy compound.

[0059] Example 2

[0060] The present example provides a method for preparing a tetraalicyclic ring epoxy compound, comprising the following steps:

[0061] Into a 500 mL three-necked flask, 6.8 g of pentaerythritol (0.05 mol), 25.23 g of 3-cyclohexene-1-formic acid (0.2 mol), 6.13 g of DMAP (0.05 mol) and dichloromethane were sequentially added to obtain a solid-liquid mixture, and 40.03 g of EDCI (0.2 mol) was dissolved in dichloromethane to obtain a first mixed solution; then the first mixed solution was added dropwise to the solid-liquid mixture, and after the dropwise addition was completed, stirring was performed at room temperature until it was observed that the solid in the solid-liquid mixture was dissolved in the organic solution, the reaction was performed for 18 h, and then the reaction system after the reaction was transferred to a separatory funnel, washed with a 1% hydrochloric acid solution three times, separated, and the lower organic phase was obtained, dried with anhydrous sodium sulfate and filtered to obtain an organic phase, and the dichloromethane and trace amount of water in the organic phase were removed by vacuum distillation under a vacuum degree of -0.098 MPa and a water bath temperature of 30-40 °C for 2 h, and then column chromatography was performed on a silica gel column (eluent: a mixture of petroleum ether and ethyl acetate with a volume ratio of 7:1) to obtain a colorless viscous liquid, and after standing and crystallization, the intermediate product was obtained in the form of white crystals. The weight of the intermediate product was 24.16 g, and the yield of the intermediate product was calculated to be 85.07%.

[0062] Into a 500 three-necked flask, dichloromethane was first added, then 5.68 g of the intermediate product (0.01 mol) was weighed and added into the three-necked flask, and then m-chloroperbenzoic acid (83% activity, 8.28 g, 0.04 mol) dissolved in 250 mL of dichloromethane was slowly added dropwise into the three-necked flask under ice bath conditions, and then the reaction was stirred at room temperature for 18 h, the intermediate product was removed by filtration, and then the filtered filtrate was treated with saturated sodium sulfite solution to remove excess m-chloroperbenzoic acid, and then treated with saturated sodium bicarbonate solution and saturated brine solution respectively for three times, and then separated to obtain the lower organic phase; the organic phase was dried with anhydrous sodium sulfate and filtered to obtain the organic phase, and then dichloromethane and a small amount of water in the organic phase were removed by vacuum distillation under the conditions of vacuum degree of -0.098 MPa and water bath temperature of 30-40 °C for 2 h, and then column chromatography was performed on a silica gel column (eluent is a mixture of petroleum ether and ethyl acetate, the volume ratio of the two is 7:1) to obtain a colorless viscous liquid, and then the colorless viscous liquid was allowed to crystallize to obtain the product in the form of white crystals. The weight of the product is 5.69 g, and the yield of the product obtained by epoxidation of the intermediate product is 90.03% according to calculation.

[0063] The structures of the intermediate product and the product were respectively confirmed by Fourier transform infrared spectroscopy (FT-IR) and hydrogen nuclear magnetic resonance (H-NMR) analysis, and the results were the same as those of Example 1, indicating that the intermediate product pentaerythritol tetracyclohexene formate and the product tetraaliphatic alicyclic epoxide were successfully synthesized.

[0064] The application of the tetraaliphatic alicyclic epoxide of the present application in solder resist dry film is described in detail below, specifically, the tetraaliphatic alicyclic epoxide prepared in Example 1 and Example 2 is used to prepare a solder resist dry film resin composition.

[0065] In the application examples and comparative examples of the present application, the alkali-soluble resin is an alkali-soluble resin synthesized with reference to Chinese Patent CN118489087A, and the preparation method thereof comprises the following steps:

[0066] Into a three-necked flask, 25 g of glycidyl methacrylate and 53 mL of propylene glycol monomethyl ether acetate were added, and then 17 g of azobisisobutyronitrile was added, and then the temperature was raised to 80 °C after nitrogen was introduced, and the reaction was carried out for 8 h; a mixed solution composed of 13.3 g of acrylic acid, 0.25 g of triphenylphosphine, 5 mg of hydroquinone and 3.25 mL of propylene glycol monomethyl ether acetate was added dropwise into the three-necked flask, and then the temperature was raised to 100 °C, and the reaction was carried out for 16 h; after the reaction, 0.925 g of succinic anhydride solution dissolved in 2.6 mL of propylene glycol monomethyl ether acetate was added into the three-necked flask, the temperature was lowered to 65 °C, and the reaction was carried out for 6 h.

[0067] The solid content, weight average molecular weight and acid value of the obtained alkali-soluble resin are determined, wherein the solid content is determined by weighing a certain amount of sample, placing it in a 120℃ oven for heating for 2h, and weighing the sample after cooling for 15min. The weight average molecular weight is measured by GPC, and the acid value is measured by titration with a sodium hydroxide standard solution.

[0068] It is detected that the solid content of the alkali-soluble resin used in the embodiment of the application is 45%, the weight average molecular weight is 7000, and the acid value is 50mgKOH / g.

[0069] It is detected that the solid content of the alkali-soluble resin used in the embodiment of the application is 45%, the weight average molecular weight is 7000, and the acid value is 50mgKOH / g.

[0070] Application Example 1

[0071] The application example provides an application of the tetraalicyclic epoxy compound prepared in Example 1 in preparation of a dry film resist resin composition, including the following steps:

[0072] According to the formula of the dry film resist resin composition shown in Table 1, the alkali-soluble resin, the photosensitive monomer, the photoinitiator, the tetraalicyclic epoxy compound prepared in Example 1, the thermal curing catalyst, the additive and the solvent are uniformly mixed, and the dry film resist resin composition is obtained.

[0073] Table 1 Formula of the dry film resist resin composition

[0074]

[0075] Application Example 2

[0076] The application example provides an application of the tetraalicyclic epoxy compound prepared in Example 2 in preparation of a dry film resist resin composition, including the following steps:

[0077] According to the formula of the dry film resist resin composition shown in Table 2, the alkali-soluble resin, the photosensitive monomer, the photoinitiator, the thermal curing resin, the thermal curing catalyst, the additive and the solvent are uniformly mixed, and the dry film resist resin composition is obtained.

[0078] Table 2 Formula of the dry film resist resin composition

[0079]

[0080]

[0081] Comparative Example 1

[0082] The comparative example provides a preparation method of a dry film resist resin composition, including the following steps:

[0083] According to the formula of the solder resist dry film resin composition shown in Table 3, the alkali-soluble resin, the photosensitive monomer, the photoinitiator, the thermal curing resin, the thermal curing catalyst, the additive, and the solvent are mixed uniformly, and thus the solder resist dry film resin composition is obtained.

[0084] Table 3 Formula of the solder resist dry film resin composition

[0085]

[0086] Experimental Example

[0087] In this experimental example, the solder resist dry film resin compositions prepared in Application Example 1, Application Example 2, and Comparative Example 1 are subjected to performance testing, so as to evaluate the comprehensive performance of the solder resist dry film of the present application.

[0088] I. Pretreatment

[0089] (1) Preparation of the photosensitive dry film: the mixed solder resist dry film resin composition is coated on the surface of a PET support film with a thickness of 25 μm using a coating machine, so as to obtain a photosensitive layer with a thickness of 25 μm, and a PE protective film with a thickness of 25 μm is overlaid on the surface of the photosensitive layer.

[0090] (2) Film lamination: the copper surface of the copper-clad plate is polished, washed with water, and dried to obtain a bright and fresh copper surface, the PE protective film is peeled off, the solder resist dry film resin composition is laminated on the copper-clad plate using a laminating machine, and the laminated plate is placed in an oven at 100°C and baked for 5 min.

[0091] (3) Exposure: the test substrate obtained after lamination is allowed to stand for 15 min, and then exposed using a laser direct imaging (LDI) exposure machine with a wavelength of 365 nm, and then the photosensitivity is tested using a stouffer 41-step exposure ruler, the exposure step number is controlled to be 14-20, and the exposure energy is 8-20 mJ / cm 2 ;

[0092] (4) Development: the sample is allowed to stand for 20 min after exposure, the PET support film is peeled off, and then developed using an alkali developing machine, a 1% Na2CO3 aqueous solution is uniformly sprayed on the surface of the sample to be developed at 30°C for a time twice as long as the developing time (60 s), and then the sample is washed with water and dried after development, so as to obtain a substrate with an evaluation solder resist dry film.

[0093] II. Performance testing

[0094] (1) Photosensitivity evaluation

[0095] The test substrate obtained after the above film pasting was placed on a Stouffer 41-stage exposure ruler for photosensitivity testing. After exposure and development, a solder resist dry film obtained by curing the solder resist dry film resin composition was formed on the surface of the test substrate. The exposure energy (mJ / cm2) was obtained when the number of remaining segments of the solder resist dry film was 20 segments for the stage exposure ruler, and the photosensitivity of the photosensitive resin composition was evaluated. The smaller the value, the better the photosensitivity. 2 ), and the photosensitivity of the photosensitive resin composition was evaluated. The smaller the value, the better the photosensitivity.

[0096] (2) Resolution Evaluation

[0097] Using a mask with a wiring pattern having an exposure part and an unexposed part with a width of 1:1, exposure was performed, and after development with 2 times the minimum development time, the minimum mask width at which a cured resist line was normally formed was observed as the value of the resolution using a two-dimensional image analyzer or a scanning electron microscope (SEM).

[0098] (3) Adhesion Evaluation

[0099] On the test substrate obtained after the above film pasting, a photomask data of a wiring pattern with L / S = n:400 (unit: μm) was used to expose with an energy that allowed the number of remaining stages of the Stouffer 41-stage exposure ruler after development to reach 20. After the development process, the resist pattern was observed using an optical microscope, and the value of the minimum line width at which a complete cured resist line was formed was used as the value of the adhesion (μm) to evaluate the adhesion. The smaller the value, the better the adhesion.

[0100] (4) Hardness Evaluation

[0101] The solder resist dry film obtained after the pretreatment was tested for hardness according to the GB / T1730-93 test method.

[0102] (5) Viscosity Evaluation

[0103] The viscosity of the solder resist dry film resin compositions of Application Example 1, Application Example 2, and Comparative Example 1 was determined according to the GB / T10247-2008 test method.

[0104] (6) Chemical Resistance Evaluation

[0105] Acid and alkali resistance test: The prepared solder resist dry film was immersed in a 50℃ 5% by mass H2SO4 solution, a 50℃ 5% by mass NaOH solution, and a 50℃ 5% by mass NaCl solution, respectively, for 30 min. The pass standard was that there was no obvious change (such as no peeling or no bubbling) on the surface of the sample.

[0106] (7) Flexibility Evaluation

[0107] After the film is pasted, exposed and developed, the prepared dry solder resist film is folded 20 times from different angles, whether the dry film cracks is observed, and the folding times when the dry film cracks is counted, the greater the value, the better the flexibility of the dry film.

[0108] III. Test results

[0109] The dry solder resist film resin composition prepared by application example 1, application example 2 and comparative example 1 is tested for the above properties, and the test results are shown in table 4.

[0110] Table 4 Test results of properties of dry solder resist film resin composition

[0111] Example 1 Example 2 Comparative Example 1 Sensitivity (mJ / cm 2 ) 25 25 27 Resolution (pm) 36 36 40 Adhesion (pm) 32 32 42 Hardness 6H 6H 4H Viscosity (cps / 25°C) 16 16 28 Chemical resistance Pass Pass Pass Flexibility Cracking after 18 times Cracking after 18 times Cracking after 8 times

[0112] As can be seen from table 4, the dry solder resist film prepared by the four official alicyclic epoxy compound as a thermosetting resin in the present application has passed the chemical resistance test, and the test results of photosensitivity and resolution are close to the dry solder resist film resin composition prepared by ERL-4221 as a thermosetting resin, which shows that the dry solder resist film composition of the present application can be used to prepare a dry solder resist film. Compared with the dry solder resist film prepared by ERL-4221 as a thermosetting resin, the dry solder resist film of the present application has slightly weaker test results of adhesion and viscosity, but the hardness and flexibility performance are significantly improved, the hardness evaluation result is 6H, and the dry film cracks after 18 times of folding in the flexibility test. The above results show that the dry solder resist film prepared by the four official alicyclic epoxy compound of the present application has acid and alkali resistance, and the properties of photosensitivity, resolution, adhesion and other properties are close to the dry solder resist film resin composition prepared by ERL-4221 as a thermosetting resin, which more effectively improves the hardness and flexibility of the dry solder resist film, so that it has good flexibility and hardness.

[0113] The above only describes some embodiments of the present application. Those skilled in the art can make several modifications and improvements without departing from the inventive concept, which are all within the scope of protection of the present application.

Claims

1. Application of tetrafunctional alicyclic epoxy compounds in the preparation of solder resist dry films, among which, The structural formula of the tetrafunctional alicyclic epoxy compound is shown in formula (I):

2. The application according to claim 1, characterized in that, The solder resist dry film prepared from the tetrafunctional alicyclic epoxy compound is used for UV encapsulation and coating protection in at least one aspect of optical display, electronic manufacturing, flat panel and flexible display devices.

3. The application according to claim 1, characterized in that, The application is the use of the tetrafunctional alicyclic epoxy compound in the preparation of a solder resist dry film resin composition, which is obtained by mixing the following raw materials in the following mass percentages: 45%–55% alkali-soluble resin, 10%–15% photosensitive monomer, 3%–4% photoinitiator, 15%–20% the tetrafunctional alicyclic epoxy compound, 0.5%–1.5% thermosetting catalyst, 0.5%–1.5% defoamer, 0.5%–1.5% leveling agent, and 15%–20% solvent.

4. The application according to claim 3, characterized in that, The molecular structure of the alkali-soluble resin contains at least one group selected from carboxyl and sulfonic acid groups. The weight-average molecular weight of the alkali-soluble resin is 6000-9000, the acid value of the alkali-soluble resin is 40-120 mgKOH / g, and the solid content of the alkali-soluble resin is 40-50%.

5. The application according to claim 3, characterized in that, The photosensitive monomer is pentaerythritol triacrylate, the photoinitiator is diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, the thermosetting catalyst is 2-methylimidazole, the leveling agent is polyacrylate, the defoamer is a silicone ether copolymer defoamer, and the solvent is acetone.

6. The application according to claim 3, characterized in that, The method of using the solder resist dry film resin composition includes the following steps: A photosensitive layer is obtained by coating a 20-30 μm thick solder resist dry film resin composition onto the surface of a 20-30 μm thick PET support film using a coating machine, and a 20-30 μm thick PE protective film is then covered on the surface of the photosensitive layer. Peel off the PE protective film, attach the solder resist dry film resin composition to the surface of the electronic component, bake at 90-110℃ for 3-10 minutes, let stand for 10-20 minutes, then expose the circuit board with a laser with a wavelength of 300-400nm, let stand for 15-30 minutes, peel off the PET support film, develop the electronic component, then wash and dry the electronic component to obtain the solder resist dry film attached to the electronic component.

7. The application according to any one of claims 1 to 3, characterized in that, The preparation method of the tetrafunctional alicyclic epoxy compound includes the following steps: S1. Pentaerythritol, 3-cyclohexene-1-carboxylic acid, catalyst and organic solvent are mixed to obtain a solid-liquid mixture. The condensing agent is dissolved in the organic solvent to obtain a first mixture. The first mixture is added dropwise to the solid-liquid mixture and stirred and reacted for 16-24 hours. The reaction system after the reaction is washed and dried to obtain an organic phase. Then the organic phase is subjected to vacuum distillation. The residue of the organic phase obtained by vacuum distillation is crystallized to obtain pentaerythritol tetracyclohexene carboxylate. S2. Dissolve pentaerythritol tetracyclohexene carboxylate in an organic solvent to obtain a second mixture, dissolve m-chloroperoxybenzoic acid in an organic solvent to obtain a third mixture, then add the third mixture dropwise to the second mixture under ice bath conditions, stir and react for 16-24 hours, filter, purify the filtrate to obtain an organic phase, crystallize to obtain a tetrafunctional alicyclic epoxy compound. The catalyst is selected from at least one of 4-dimethylaminopyridine, 1-hydroxybenzotriazole, and 4-pyrrolidinylpyridine; the condensing agent is selected from at least one of N,N-dicyclohexylcarbodiimide, N,N-diisopropylcarbodiimide, and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide; and the organic solvent is selected from at least one of tetrahydrofuran and dichloromethane.

8. The application according to claim 7, characterized in that, The molar ratio of pentaerythritol, 3-cyclohexene-1-carboxylic acid, catalyst and condensing agent is 1:(4-4.12):(1-1.10):(4-4.10), and the molar ratio of pentaerythritol tetracyclohexene carboxylate to m-chloroperoxybenzoic acid is 1:(4-4.10).

9. The application according to claim 7, characterized in that, In step S1, the washing process is as follows: the reaction system after reaction is transferred to a separatory funnel, an organic solvent is added to the separatory funnel, and the system is washed three times with a 1% hydrochloric acid solution, and then washed three times with a saturated sodium chloride solution. The lower organic phase is obtained by separation. Alternatively, transfer the reaction system after the reaction to a separatory funnel, add 10-50 mL of organic solvent to the separatory funnel, wash three times with 1% hydrochloric acid solution, then wash three times with saturated sodium bicarbonate solution, and then wash three times with saturated sodium chloride solution. Separate the mixture to obtain the lower organic phase. Alternatively, transfer the reaction system after the reaction to a separatory funnel, add 10-50 mL of organic solvent to the separatory funnel, wash the organic phase three times with a 1% hydrochloric acid solution, and separate to obtain the lower organic phase.

10. The application according to claim 7, characterized in that, In step S1, the method for obtaining the organic phase by drying the reaction system after the reaction is to add a solid desiccant to the washed reaction system, filter and retain the organic phase; In step S2, the purification process is as follows: first, saturated sodium sulfite solution is added dropwise to the filtrate, then the filtrate is washed three times with saturated sodium bicarbonate solution and saturated sodium chloride solution respectively, the lower organic phase is obtained by separation, a solid drying agent is added to the washed organic phase, and then the organic solvent in the organic phase is removed by vacuum distillation. The conditions for vacuum distillation are as follows: the filtered organic phase is distilled under vacuum of -0.098 MPa and water bath temperature of 30-40°C for 1-3 hours.

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