Photosensitive resin composition and photosensitive cured film

Abstract

The present invention relates to the field of polymer materials, and provides a photosensitive resin composition and a photosensitive cured film. The photosensitive resin composition comprises (a) an alkali-soluble resin, (b) a photosensitizer, (c) a crosslinking agent, (d) an adhesion modifier, and (e) a solvent; wherein the crosslinking agent (c) comprises a crosslinker (c1) having the structure represented by general formula (1), and (c1) accounts for 1-20% of the total mass of the crosslinking agent (c). By using a certain proportion of the crosslinker (c1) in the crosslinking agent, the present invention achieves a photosensitive resin composition capable of low-temperature curing (the curing temperature being less than or equal to 250°C). Furthermore, by optimizing the structure of the alkali-soluble resin, the invention can provide a photosensitive cured film exhibiting good light transmittance and heat resistance without the addition of fluorine elements.

Description

Photosensitive resin composition and photosensitive cured film Cross-references

[0001] This application claims priority to Chinese Patent Application No. 202410037524.1 filed on January 10, 2024, entitled “A Photosensitive Resin Composition and Photosensitive Cured Film,” the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0002] The present invention relates to the field of polymer materials, in particular to a photosensitive resin composition and a photosensitive cured film. Background Art

[0003] Due to its unique aromatic ring conjugation and imide ring structure, polyimide exhibits excellent heat resistance, high insulation, chemical resistance and good mechanical properties. It is widely used in surface passivation layers, stress buffer layers and interlayer insulation layers of semiconductor devices. It also has important application value in signal line distribution, α-particle shielding layers, micro-solder ball processing, stress buffer layers of plastic-encapsulated circuits, flexible packaging substrates, etc. in advanced semiconductor packaging (BGA, CSP, SiP, WLP, etc.). At the same time, in display devices such as organic EL display devices or liquid crystal display devices, photosensitive polyimide resins are widely used in the flat layer and pixel definition layer of the display device to improve interlayer insulation and reduce display color difference.

[0004] The unique aromatic ring conjugation structure in polyimide (PI) leads to the formation of intra- and intermolecular charge transfer complexes (CTCs). This requires higher curing temperatures for polyimide (PI), further limiting its application in display devices such as organic EL and liquid crystal displays (LCDs), and fan-out wafer packaging (FO-WLP). Therefore, achieving low-temperature curing remains an urgent challenge. Summary of the Invention

[0005] In view of the problems existing in the prior art, the present invention provides a photosensitive resin composition and a photosensitive cured film.

[0006] In a first aspect, the present invention provides a photosensitive resin composition comprising (a) an alkali-soluble resin, (b) a photosensitive compound, (c) a crosslinking agent, (d) an adhesion modifier, and (e) a solvent;

[0007] wherein (c) the cross-linking agent comprises a cross-linking agent (c1) having a structure represented by general formula (1), and (c1) accounts for 1 to 20% of the total mass of the cross-linking agent (c);

[0008] General formula (1)

[0009] Wherein, R1 represents one of a phenyl ring, a naphthalene ring, an anthracene ring, an imidazole ring, and an oxazole ring; R2 = -R3-NH2 or -R3-COOH, and R3 represents an organic group with 1 to 12 carbon atoms.

[0010] The present invention obtains a photosensitive resin composition capable of low-temperature curing (curing temperature ≤ 250°C) by adopting a certain proportion of a crosslinking agent (C1) in a crosslinking agent. The crosslinking agent (C1) is a multifunctional small molecule monomer, which can improve the curing crosslinking degree during the curing process and achieve low-temperature crosslinking curing together with a conventional crosslinking agent. The proportion of the crosslinking agent (C1) should not be too low, as a too low proportion will result in low crosslinking density and difficulty in achieving good low-temperature curing properties. A too high proportion will easily result in excessive curing crosslinking and reduced heat resistance.

[0011] Preferably, the crosslinking agent (c1) represented by the general formula (1) is selected from the group consisting of the following structures:

[0012]

[0013] It should be noted that, in addition to crosslinker (c1), the crosslinking agent (c) may also include conventional crosslinking agents in the art, namely, thermally crosslinkable compounds capable of undergoing a crosslinking reaction with the alkali-soluble resin. Specifically, the crosslinking agent may be selected from one or more of epoxy compounds, alkoxymethylol compounds, and alkoxymethylol triazine ring compounds; preferably, the functionality of such compounds is greater than or equal to 2.

[0014] The epoxy compound is selected from one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, and propylene glycol diglycidyl ether.

[0015] The alkoxymethylol compound is selected from polyalkoxymethylolated phenolic hydroxyl compounds, wherein the phenolic hydroxyl compound is selected from one or more of Bis-Z, BisP-EZ, BisOPP-Z, BisP-CP, BisP-EZ, TekP-4HBPA, TrisP-HAP, TrisP-PA, Tris-PHBA, TrisP-SA, TrisOCR-PA, BisOCHP-Z, BisP-MZ, and BisP-PZ (trade names, manufactured by Honshu Chemical Industry Co., Ltd.).

[0016] The alkoxy hydroxymethyl triazine ring compound is selected from one or more compounds represented by general formula (6);

[0017] General formula (6)

[0018] Among them, R9 and R 10 Each independently represents H, CH2OCH3 or CH2OCH2CH3, and not all are H.

[0019] According to the photosensitive resin composition provided by the present invention, the (a) alkali-soluble resin includes a compound represented by general formula (2) and a compound represented by general formula (3),

[0020] General formula (2)

[0021] Wherein, in the general formula (2), Ar1 represents a dianhydride residue; Ar2 represents a diamine residue, and Ar1 and Ar2 contain at least one phenolic hydroxyl group or one sulfonyl group (-S(=O)2-); R4 represents a fluorine-free organic group having 1 to 10 H or C atoms; m is an integer from 10 to 10000, and r is an integer from 0 to 2;

[0022] General formula (3)

[0023] Wherein, in the general formula (3), Ar3 represents a dianhydride residue; Ar4 represents a diamine residue, and the diamine residue Ar4 comprises at least two structural units, one of which is as shown in the general formula (4) or the general formula (5);

[0024] General formula (4)

[0025] Wherein, in the general formula (4), R5 and R6 are the same or different and independently represent -(CH2)- or -(CH2CH2)-; L1, L2, L3, and L4 are the same or different and independently represent H or a non-fluorine halogen element;

[0026] General formula (5)

[0027] Wherein, in the general formula (5), R7 and R8 are the same or different and independently represent -(CH2)- or -(CH2CH2)-; L5, L6, L7, and L8 are the same or different and independently represent H or a non-fluorine halogen element;

[0028] Ar1, Ar2, Ar3 and Ar4 do not contain fluorine element.

[0029] It should be noted that the "non-fluorine halogen elements" mentioned in the above technical solution refer to chlorine, bromine or iodine.

[0030] The dianhydride residues (Ar1 and Ar3) are residues obtained by removing two anhydride groups from a dianhydride. The dianhydrides include, but are not limited to, the following dianhydrides, such as pyromellitic dianhydride (PMDA), 3,3,3',4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (α-BPDA), 4,4'-oxydiphthalic anhydride (ODPA), 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), p-phenylene-trimethylbenzene dianhydride (TAHQ), 3,3',4 , one or more of 4'-diphenylsulfonetetracarboxylic dianhydride (BSDA), cyclobutanetetracarboxylic dianhydride (CBDA), cyclohexanetetracarboxylic dianhydride (HPMDA), N-[5-[3-[(1,3-dioxy-2-benzofuran-5-carbonyl)amino]-4-hydroxyphenyl]sulfonyl-2-hydroxyphenyl]-1,3-dioxy-2-benzofuran-5-carboxamide and 3,3,4,4-diphenylsulfonetetracarboxylic dianhydride (DSDA).

[0031] The diamine residues (Ar2 and Ar4) are residues obtained by removing two amino groups from a diamine. The diamines include but are not limited to the following diamines, such as 2,2-bis(4-hydroxy-3-aminophenyl)propane (BAP), 3,3'-diamino-4,4'-dihydroxydiphenyl sulfone (BAHS), N,N'-[(1-methylethylidene)bis(6-hydroxy-3,1-phenylene)]bis[3-aminobenzamide, 4,4'-bis(3-aminophenoxy)diphenyl sulfone, 2,2-bis[3-(4-aminobenzamido)-4-hydroxyphenyl]propane, 2,2-bis [3-(4-aminobenzamido)-4-hydroxyphenyl]sulfone, 2,2-bis[3-(4-aminobenzamido)-4-hydroxyphenyl]ether, N-(2-hydroxy-5-amino)phenyl-3-aminobenzamide, N-(5-amino-2-hydroxyphenyl)-4-[2-[4-[(4-aminophenyl)carbamoyl]phenyl]-propan-2-yl]benzamide, N-(5-amino-2-hydroxyphenyl)-4-[2-[4-[(4-aminophenyl)carbamoyl]phenyl]-propan-2-yl]benzamide ]phenyl]-sulfone-2-yl]benzamide, N-(5-amino-2-hydroxyphenyl)-4-[2-[4-[(4-aminophenyl)carbamoyl]phenyl]-ether-2-yl]benzamide, 1,4-p-phenylenediamine (PDA), m-phenylenediamine (m-PDA), o-phenylenediamine (o-PDA), 4,4'-diaminodiphenyl ether (ODA), 4,4'-diamino-p-terphenyl (DATP), 4,4'-methylenedianiline (MDA), 2,2'- One or more of dimethyl-4,4'-diaminobiphenyl (m-TB), p-aminophenyl para-aminobenzoate (APAB), 1,4-bis(4'-aminophenoxy)benzene (1,4,4-APB), 1,3,4-APB:1,3-bis(4'-aminophenoxy)benzene (1,3,4-APB), 1,3-bis(3'-aminophenoxy)benzene (1,3,3-APB) and 2,2-bis(4-(4-aminophenoxy)phenyl)propane (BAPP).

[0032] Ar1 and Ar2 contain at least one phenolic hydroxyl group or one sulfonyl group (-S(=O)2-). In other words, among the raw dianhydrides and diamines used to form general formula (2), at least one raw material monomer contains a phenolic hydroxyl group or a sulfonyl group (-S(=O)2-) structure, or both structures may be present. These two structures may appear simultaneously on one monomer or on different monomers. In addition, during the preparation of the compound represented by general formula (2), the weight proportion of monomers containing phenolic hydroxyl groups, sulfonyl groups, or a combination of the two groups in the total monomers is ≥30%.

[0033] It should be noted that when R4 represents H, the alkali-soluble resin is a polyamic acid soluble in an alkaline aqueous solution; when R4 represents an organic group with 1 to 10 C atoms, the alkali-soluble resin is a polyamide ester soluble in an alkaline aqueous solution, and preferably, the organic group is an alkyl group.

[0034] The unique aromatic ring conjugated structure in the polyimide structure leads to the formation of intramolecular and intermolecular charge transfer complexes (CTCs), which greatly affects the light transmittance of polyimide (PI) films, resulting in a brownish-yellow color and poor light transmittance, limiting the development of PI films in the optoelectronic field. In order to achieve good organic solvent solubility and excellent optical properties (such as transmittance), fluorine elements or fluorine-containing structures are often introduced to destroy the conjugation in the polyimide structure to achieve improved optical performance. However, with the increasing awareness of environmental protection, the demand for fluorine-free materials is becoming increasingly apparent.

[0035] The present invention has found that when the structure contains phenolic hydroxyl groups, the resulting alkali-soluble resin has better alkali solubility; when the structure contains sulfonyl groups (-S(=O)2-) and alicyclic structures, the resulting alkali-soluble resin has better organic solvent solubility and better optical transmittance.

[0036] In a specific embodiment of the present invention, good alkali solubility is achieved by adjusting the structural ratio of general formula (2) and general formula (3); by introducing a phenolic hydroxyl group, a sulfonyl group (-S(=O)2-) or a combination of the two, and a structural unit represented by general formula (4) or general formula (5) into the alkali-soluble resin structure, an alkali-soluble resin with good organic solvent solubility is obtained under the condition of not containing fluorine element.

[0037] Specifically, the alkali-soluble resin has good solubility in organic solvents, which is embodied in that it is soluble in one or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, tetrahydrofuran, propylene glycol methyl ether, propylene glycol monoethyl ether, ethylene glycol monomethyl ether, γ-butyrolactone, methyl lactate, ethyl lactate, propyl lactate and butyl lactate.

[0038] In some embodiments of the present invention, the compound represented by general formula (2) accounts for 10% to 40% of the total mass of the compound represented by general formula (2) and the compound represented by general formula (3).

[0039] The present invention has found that the higher the specific gravity of the compound represented by general formula (2) in the alkali-soluble resin, the better. If the specific gravity is too high, it is difficult to achieve both organic solvent solubility and light transmittance, and if the specific gravity is too low, it is difficult to achieve alkali dissolution.

[0040] In order to further improve the light transmittance and achieve low-temperature curing, during the preparation of the compound represented by general formula (3), the proportion of the diamine monomers forming the general formula (4) and the diamine monomers forming the general formula (5) in the total mass of the diamine monomers is ≥60%.

[0041] In some embodiments of the present invention, the diamine forming the general formula (4) is selected from the group consisting of the following structures:

[0042] .

[0043] In some embodiments of the present invention, the diamine structure forming the general formula (5) is as follows:

[0044] .

[0045] The preparation method of the alkali-soluble resin of the present invention comprises the following steps:

[0046] (1) preparing the desired diamine (a diamine represented by two amino groups connected at both ends of the general formula (4) or (5)) according to the self-designed structure and process, and performing purification and other post-treatments for use;

[0047] (2) Under the protection of inert gas, materials such as phenolic hydroxyl group, sulfonyl group (-S(=O)2-) monomer, other diamine (optionally added) and dianhydride (optionally added) are successively dissolved in an organic solvent, and a polyimide precursor solution 1 with a solid content of 10-50% is obtained by polymerization reaction, or a diester solution is obtained by esterification of dianhydride and alcohol, and then further reacted with diamine after chlorination or DCC treatment to obtain a polyimide precursor solution 1 with a solid content of 10-50%; alicyclic diamine (a diamine represented by two amino groups connected at both ends of the general formula (3) or (4), other diamine (optionally added) and dianhydride (optionally added) are successively dissolved in an organic solvent, and a polyimide solution 2 with a solid content of 10-50% is obtained by high-temperature polymerization reaction; the two are mixed and stirred at room temperature to obtain a polyimide resin solution (a small amount of copolymerization occurs under room temperature mixing);

[0048] (3) The resin is precipitated using a precipitant, and the target alkali-soluble resin is obtained after filtration, washing and drying.

[0049] According to the photosensitive resin composition provided by the present invention, the (b) photosensitizer is a naphthoquinone azide photosensitizer.

[0050] The naphthoquinone azide photosensitizer is an esterified product of a phenolic hydroxyl group-containing compound and naphthoquinone azide sulfonyl chloride. The phenolic hydroxyl group-containing compound is selected from one or more of Bis-Z, BisP-EZ, BisOPP-Z, BisP-CP, BisP-EZ, TekP-4HBPA, TrisP-HAP, TrisP-PA, Tris-PHBA, TrisP-SA, TrisOCR-PA, BisOCHP-Z, BisP-MZ, and BisP-PZ (trade names, manufactured by Honshu Chemical Industry Co., Ltd.).

[0051] According to the photosensitive resin composition provided by the present invention, the (d) adhesion modifier includes but is not limited to one or more of the following: γ-glycidyloxypropyltrimethoxysilane (KH560), γ-aminopropyltriethoxysilane (KH550), γ-aminopropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, p-aminophenyltrimethoxysilane, 3-(m-aminophenoxy)trimethoxysilane, 3-mercaptomethyltrimethoxysilane, and 3-mercaptopropyltriethoxysilane.

[0052] According to the photosensitive resin composition provided by the present invention, the (e) solvent is one or more of ketone solvents, ester solvents, ether solvents, aromatic hydrocarbon solvents and other solvents.

[0053] By way of example but not limitation, the ketone solvent is one of acetone, methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone, cyclopentanone and cyclohexanone.

[0054] The ester solvent is one or more of ethyl acetate, butyl acetate, n-propyl acetate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, propylene glycol methyl ether acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate and gamma-butyrolactone.

[0055] The ether solvent is one or more of propylene glycol methyl ether, propylene glycol monoethyl ether, and ethylene glycol monomethyl ether.

[0056] The aromatic hydrocarbon solvent may be one or more of toluene and xylene.

[0057] The other solvents are one or more of N-methylpyrrolidone, tetrahydrofuran, dioxane, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide.

[0058] It is understandable that in order to achieve the fluorine-free nature of the entire photosensitive resin composition, when the alkali-soluble resin does not contain fluorine, the remaining components also do not contain fluorine.

[0059] In some embodiments of the present invention, relative to 100 parts of (a) alkali-soluble resin, the amount of (b) photosensitizer is 0.05-50 parts, the amount of (c) cross-linking agent is 1-50 parts, the amount of (d) adhesion modifier is 0.01-10 parts, and the amount of (e) solvent is appropriately selected based on the solid content of 5-40%.

[0060] In a second aspect, the present invention provides a photosensitive cured film formed by curing any one of the above-mentioned photosensitive resin compositions.

[0061] Those skilled in the art will appreciate that curing the photosensitive resin composition to form a cured film typically involves some pre-treatment, such as coating, hot plate drying, exposure, and development before curing. Each step employs conventional techniques in the art. For example, coating may be performed using a rotational viscometer, drying may be performed using a hot plate, and curing may be performed thermally under nitrogen.

[0062] Due to the specific structure of the alkali-soluble resin in the photosensitive resin composition, the photosensitive cured film of the present invention has good light transmittance and heat resistance; the average light transmittance of the photosensitive cured film at 380-780nm is ≥70%; and the thermal weight loss temperature T5% is ≥300°C.

[0063] The photosensitive cured film of the present invention can be applied to surface protective films and interlayer insulating films of semiconductor elements, insulating layers of organic electroluminescent elements, and insulating layers of thin film transistors.

[0064] The present invention provides a photosensitive resin composition and a photosensitive cured film. By using a certain proportion of a crosslinking agent (C1) in a crosslinking agent, a photosensitive resin composition that can be cured at a low temperature (curing temperature ≤ 250°C) is obtained. Furthermore, by optimizing the structure of an alkali-soluble resin, a photosensitive cured film with good light transmittance and heat resistance can be obtained without adding fluorine. DETAILED DESCRIPTION

[0065] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention are described clearly and completely below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0066] Unless otherwise specified, the technical means used in the examples of the present invention are conventional means well known to those skilled in the art. Unless otherwise specified, the materials and reagents used in the examples of the present invention can be obtained through regular commercial channels.

[0067] The abbreviations of the compounds in the following examples are:

[0068] PDA: p-phenylenediamine

[0069] BAP:2,2-bis(4-hydroxy-3-aminophenyl)propane

[0070] BAHS:3,3'-diamino-4,4'-dihydroxydiphenyl sulfone

[0071] ODPA:4,4'-oxydiphthalic anhydride

[0072] DSDA:3,3,4,4-diphenylsulfone tetracarboxylic dianhydride

[0073] DMFDEA: N,N'-dimethylformamide diethyl acetal

[0074] MAP: meta-aminophenol

[0075] TrisP-HAP: 1,1,1-Tris(4-hydroxyphenyl)ethane

[0076] Synthesis Example 1 Synthesis of diamines (I-1) and (I-2)

[0077]

[0078] The synthesis route is as follows:

[0079]

[0080] (1) Synthesis of compound I-1

[0081] 25.4 g of compound I-1-1 and 200 ml of tetrahydrofuran were added to the reactor, and ammonia gas was introduced to a pressure of 0.5-1.0 MPa at room temperature. The temperature was raised to 200 ° C and the reaction was carried out for 6 hours. The temperature was lowered and the pressure was reduced. The reaction was quenched with saturated sodium bicarbonate aqueous solution. Conventional post-treatment was performed and recrystallized from n-heptane to obtain 25.1 g of an off-white solid (compound I-1), HPLC: 99.6%, yield 87.2%.

[0082] The obtained white solid compound I-1 was analyzed by GC-MS, and the m / z of the product was 246.2 (M+).

[0083] (2) Synthesis of compound I-2

[0084] Compound I-2 was prepared using the same mechanism as above, but the yield was low, so the subsequent synthesis example 9 is currently in the laboratory stage.

[0085] Synthesis Example 2 Synthesis of diamine (I-3)

[0086]

[0087] The synthesis route is as follows:

[0088]

[0089] (1) Synthesis of compound I-3-2

[0090] Under nitrogen protection, 36.0 g of compound I-3-1 and 200 ml of tetrahydrofuran were added to the reaction flask, and 68.3 g of pyridine hydrogen fluoride was added dropwise at a temperature of -10~0 ° C. After the addition, the reaction was kept warm for 2 hours. A saturated aqueous sodium bicarbonate solution was added to quench the reaction, and conventional post-treatment was performed. Recrystallization from n-heptane gave 30.5 g of a light yellow solid (compound I-3-2), HPLC: 99.3%, and a yield of 72.6%.

[0091] (2) Synthesis of compound I-3

[0092] Under nitrogen protection, 14.2 g of ammonium formate, 200 ml of methanol, 30.0 g of compound I-3-2, 10 ml of acetic acid, and 0.001 g of iridium catalyst (Ir-3) were added to the reaction flask. The reaction was refluxed for 8 hours at 75 ° C. The temperature was cooled to room temperature and quenched by adding saturated aqueous sodium hydroxide solution. Conventional post-processing operations were then performed, and the mixture was dissolved in dichloromethane and separated. The mixture was purified by chromatography and recrystallized from a mixed solution of n-heptane and toluene in a volume ratio of 3:1 to obtain 23.7 g of a white solid (compound I-3), HPLC: 99.8%, and a yield of 78.5%.

[0093] The obtained white solid compound I-3 was analyzed by GC-MS, and the m / z of the product was 246.2 (M+).

[0094] Synthesis Example 3 Synthesis of photosensitizer (PAC-1)

[0095]

[0096] The reaction vessel was vented with nitrogen in advance. After 30 minutes, 260 g of dioxane (water was removed with molecular sieves 24 hours in advance) was added, and then 10.60 g (0.025 mol) of TrisP-PA (trade name, made by Honshu Chemical) and 20.1 g (0.075 mol) of naphthoquinone azidosulfonyl chloride were added respectively. A mixed solution of triethylamine (6.3 g) and dioxane (20 g) was slowly added dropwise, and the temperature was controlled within 30°C. After the addition was completed, the mixture was kept at 30°C for 2 hours. The mixture was filtered, washed with deionized water three times, rinsed with dilute hydrochloric acid and deionized water three times respectively, and dried in a vacuum at 60°C for 24 hours.

[0097] Synthesis Example 4 Synthesis of photosensitizer (PAC-2)

[0098] The photosensitizer PAC-2 was prepared by a similar synthesis method to that in Synthesis Example 3, except that TrisP-PA (trade name, manufactured by Honshu Chemical) was replaced by Trisp-HAP (trade name, manufactured by Honshu Chemical).

[0099]

[0100] Synthesis Example 5 Synthesis of Cross-linking Agent (C-2-1)

[0101] The reaction vessel was vented with nitrogen in advance. After 30 minutes, 200 g of water was added, followed by 20 g (0.5 mol) of NaOH and 25.8 g (0.1 mol) of 1,1,1-tris(4-hydroxyphenyl)ethane. After sufficient dissolution, 18 eq of formaldehyde solution was slowly added dropwise, with the temperature controlled below 20°C. After the addition was complete, the temperature was kept at 20°C for 24 hours. Sulfuric acid and water were added to neutralize the product to obtain a white product, which was washed three times with deionized water and dried under vacuum at 50°C for 72 hours.

[0102] The dried white product was further reacted with methanol at room temperature for 24 h, and the methanol was removed by distillation under reduced pressure to obtain the cross-linking agent C-2-1.

[0103]

[0104] Synthesis Example 6 Synthesis of Cross-linking Agent (C-2-2)

[0105] Cross-linking agent C-2-2 was prepared by a similar synthesis method to that in Synthesis Example 5, except that Trisp-HAP (trade name, manufactured by Honshu Chemical) was replaced with melamine.

[0106]

[0107] Synthesis Example 7 Synthesis of Polyimide Resin A-1

[0108] The reaction vessel was vented with nitrogen in advance. After 30 minutes, 62.62 g of N-methylpyrrolidone (NMP, dehydrated with molecular sieves 24 hours in advance) was added, followed by 3.88 g (0.015 mol) of BAP, and the mixture was stirred at 25°C until completely dissolved. 7.17 g (0.02 mmol) of DSDA was then added, and the mixture was stirred at room temperature for 12 hours. 1.09 g (0.01 mol) of MAP was added, and the mixture was kept warm for 12 hours. 9.33 g of DMFDEA was added, and the temperature was raised to 60°C, kept warm for 4 hours, and then cooled to room temperature to obtain resin solution A-1-1.

[0109] The reaction vessel was vented with nitrogen in advance. After 30 minutes, 94.60 g of N-methylpyrrolidone (NMP, dehydrated with molecular sieves 24 hours in advance) was added, followed by 7.39 g (0.03 mol) of I-1. The mixture was stirred at 25°C until completely dissolved. 9.30 g (0.03 mmol) of compound ODPA was then added. The mixture was stirred at room temperature for 12 hours. 16 g of toluene was added, the temperature was raised to 160°C, refluxed to remove water, the temperature was maintained for 4 hours, and the mixture was cooled to room temperature to obtain resin solution A-1-2.

[0110] Resin solutions A-1-1 and A-1-2 were mixed and stirred at room temperature for 12 hours to obtain polyimide resin A-1 solution, which was added into 3 L of deionized water, precipitated, filtered, and washed three times; and vacuum dried at 80°C for 72 hours to obtain polyimide resin A-1.

[0111] Synthesis Examples 8-12 Synthesis of Polyimide Resins A-2-A-6

[0112] As shown in Table 1, resin solutions A-2-1, A-3-1, A-4-1, A-5-1, and A-6-1 were prepared by replacing 30 parts of BAP with 30 parts of BAHS or PDA, respectively, and using the same formula and process as resin solution A-1-1;

[0113] Resin solutions A-2-2, A-3-2, A-4-2, A-5-2, and A-6-2 were prepared by replacing 60 parts of I-1, I-2, I-3, PDA, and PDA with 60 parts of I-1, and replacing 60 parts of DSDA with 60 parts of ODPA, respectively, using the same formula and process as resin solution A-2-1;

[0114] In the same manner as A-1-2 and A-2-2, the mixtures were mixed and stirred at room temperature for 12 h to obtain polyimide resins A-2 to A-6 solutions, which were then added into 3 L of deionized water, precipitated, filtered, and washed three times; and vacuum dried at 80°C for 72 h to obtain polyimide resins A-2 to A-6.

[0115] Synthesis Example 13 Synthesis of Polyimide Resin A-7

[0116] As shown in Table 1, resin solution A-7 was prepared by replacing 30 parts of BAP with 90 parts of PDA, replacing 60 parts of ODPA and 40 parts of DSDA with 100 parts of ODPA and following the same formula and process as resin solution A-1-1;

[0117] The reaction was continued under stirring at room temperature for 12 h to obtain a polyimide resin A-7 solution, which was then added into 3 L of deionized water, precipitated, filtered, and washed three times; and vacuum dried at 80° C. for 72 h to obtain a polyimide resin A-7.

[0118] Table 1

[0119]

[0120] Example 1

[0121] 10 g of the polyimide resin A-1 obtained in Synthesis Example 7, 1 g of PAC-1 obtained in Synthesis Example 3, 2 g of PAC-2 obtained in Synthesis Example 4, 0.1 g of silane coupling agent γ-glycidyloxypropyltrimethoxysilane, 0.2 g of 3,5-diaminobenzoic acid, 0.8 g of the cross-linking agent C-2-1 obtained in Synthesis Example 5, and 0.2 g of the cross-linking agent C-2-2 obtained in Synthesis Example 6 were dissolved in 30 g of γ-butyrolactone and thoroughly mixed to obtain a photosensitive resin composition.

[0122] Examples 2-4

[0123] In Examples 2 to 4, polyimide resins A-2 to A-4 were used to replace polyimide resin A-1, and 2,4-diaminobenzoic acid, 2,3-diaminobenzoic acid and 2,5-dicarboxyaniline were used to replace 3,5-diaminobenzoic acid. Photosensitive resin compositions were prepared in the same manner as in Example 1.

[0124] Comparative Examples 1~3

[0125] In Comparative Examples 1 to 3, polyimide resins A-5 to A-7 were used to replace polyimide resin A-1, respectively, and photosensitive resin compositions were prepared in the same manner as in Example 1.

[0126] Comparative Example 4

[0127] Without adding 3,5-diaminobenzoic acid, the other steps were similar to those in Example 1 to obtain a photosensitive resin composition.

[0128] Resins A-1 to A-7 obtained in Synthesis Examples 7 to 13 were tested for their solubility in organic solvents. 1 g of each resin was dissolved in 9 g of solvent and stirred for 12 hours. The solubility was observed. The results are summarized in Table 2. Among them, amides include: N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and dimethyl sulfoxide; ethers include: propylene glycol methyl ether, propylene glycol monoethyl ether, and ethylene glycol monomethyl ether; and esters include: γ-butyrolactone, methyl lactate, ethyl lactate, propyl lactate, and butyl lactate.

[0129] Table 2

[0130]

[0131] The photosensitive resin compositions obtained in the examples and comparative examples were used to prepare photocured films according to the following preparation methods, and the properties of the obtained photocured films were measured according to the following methods. The results are summarized in Table 3.

[0132] Preparation of photosensitive curing film: Wet film coating is performed using a rotational viscometer (Mikasa: MS-B150+DA-60S), pre-dried on a hot plate, and then transferred to a nitrogen oven for further curing after exposure and development. Curing is carried out at 150-250°C for 30-180 minutes, and then cooled to room temperature and removed.

[0133] (1) Transmittance (T%)

[0134] The results were obtained using an Agilent UV-visible spectrophotometer Cary 4000 in transmission mode.

[0135] (2) Thermal weight loss temperature (T5%)

[0136] The thermal decomposition temperature was measured using a thermogravimetric analyzer (model TGA-55) with a heating rate of 10°C / min, a sample size of 3-5 mg, and a temperature range of RT-500°C.

[0137] Table 3

[0138]

[0139] As can be seen from the data in Table 2, the alkali-soluble resin provided by the present invention has good solubility in organic solvents and is well soluble in solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, tetrahydrofuran, propylene glycol methyl ether, propylene glycol monoethyl ether, ethylene glycol monomethyl ether, γ-butyrolactone, methyl lactate, ethyl lactate, propyl lactate and butyl lactate. It is suitable for providing an alkali-soluble resin solution with good solubility in organic reagents without the presence of fluorine element; and provides an environmentally friendly photosensitive resin composition solution.

[0140] As can be seen from the data in Table 3, the photosensitive resin composition, after coating with a rotational viscometer, hot plate drying, exposure, development, and heat curing under nitrogen, exhibits excellent light transmittance and good heat resistance in the photocured film even when cured at ≤250°C. The composition of Example 1 was also cured at a lower temperature (200°C), and the results showed that good curing and crosslinking effects were still achieved, maintaining good transmittance and heat resistance. The average light transmittance (380-780nm) was ≥70%, and the thermal weight loss temperature T5% was ≥300°C. The composition is suitable for use as surface protective films and interlayer insulating films for semiconductor devices, insulating layers for organic electroluminescent devices, and insulating layers for thin-film transistors.

[0141] By selecting a suitable alkali-soluble resin and combining different types and proportions of cross-linking agents (the ratio of cross-linking agents (c1) and (c2)), low-temperature curing can be achieved while maintaining good heat resistance. In addition, by adjusting the structural ratio of general formula (2) and general formula (3), phenolic hydroxyl groups, sulfonyl groups (-S(=O)2-) or a combination of the two, as well as structural units represented by general formula (4) or general formula (5) are introduced into the alkali-soluble resin structure to achieve good alkali solubility, organic reagent solubility and light transmittance. This can be used to solve the problems of poor organic solvent solubility, low light transmittance and poor heat resistance in the prior art without fluorine element.

[0142] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention. Industrial Applicability

[0143] The present invention relates to the field of polymer materials and provides a photosensitive resin composition and a photosensitive cured film. The photosensitive resin composition comprises (a) an alkali-soluble resin, (b) a photosensitizer, (c) a crosslinking agent, (d) a bonding modifier, and (e) a solvent. The crosslinking agent (c) comprises a crosslinking agent (c1) having a structure represented by the general formula (1), and (c1) accounts for 1 to 20% of the total mass of the crosslinking agent (c). The present invention provides a photosensitive resin composition that can be cured at low temperatures (curing temperature ≤ 250°C) by using a certain proportion of the crosslinking agent (c1). Furthermore, by optimizing the structure of the alkali-soluble resin, a photosensitive cured film having good light transmittance and heat resistance can be obtained without adding fluorine.

[0144]

Claims

1. A photosensitive resin composition, characterized in that, Comprising (a) an alkali-soluble resin, (b) a photosensitizer, (c) a crosslinking agent, (d) a binder modifier, and (e) a solvent; Among them, the (c) crosslinking agent includes a crosslinking agent (c1) having the structure shown in the general formula (1), and (c1) accounts for 1 to 20% of the total mass of the (c) crosslinking agent; General formula (1) In the formula, R1 represents one of a phenyl group, a naphthalene ring, an anthracene ring, an imidazole ring, and an oxazole ring; R2 = -R3-NH2 or -R3-COOH, and R3 represents an organic group having 1 to 12 carbon atoms.

2. The photosensitive resin composition according to claim 1, wherein The crosslinking agent (c1) represented by the general formula (1) is selected from the group consisting of the following structures: 。 3. The photosensitive resin composition according to claim 1, wherein The (a) alkali-soluble resin includes a compound represented by the general formula (2) and a compound represented by the general formula (3). General formula (2) Among them, in the general formula (2), Ar1 represents a dianhydride residue; Ar2 represents a diamine residue, and at least one of Ar1 and Ar2 contains a phenolic hydroxyl group or a sulfonyl group; R4 represents H or a fluorine-free organic group having 1 to 10 carbon atoms; m is an integer from 10 to 10,000, and r is an integer from 0 to 2; General formula (3) Among them, in the general formula (3), Ar3 represents a dianhydride residue; Ar4 represents a diamine residue, and the diamine residue Ar4 includes at least two structural units, and one of the structural units is shown in the general formula (4) or the general formula (5); General formula (4) Among them, in the general formula (4), R5 and R6 are the same or different and independently represent -(CH2)- or -(CH2CH2)-; L1, L2, L3, and L4 are the same or different and independently represent H or a non-fluorine halogen element; General formula (5) Among them, in the general formula (5), R7 and R8 are the same or different and independently represent -(CH2)- or -(CH2CH2)-; L5, L6, L7, and L8 are the same or different and independently represent H or a non-fluorine halogen element; Ar1, Ar2, Ar3, and Ar4 do not contain fluorine elements.

4. The photosensitive resin composition according to claim 3, wherein In the (a) alkali-soluble resin, the proportion of the compound represented by the general formula (2) in the total mass of the compound represented by the general formula (2) and the compound represented by the general formula (3) is 10% to 40%.

5. The photosensitive resin composition according to claim 3 or 4, characterized in that During the preparation of the compound represented by the general formula (2), the monomer containing a phenolic hydroxyl group, a sulfonyl group, or a combination of both accounts for a mass ratio of ≥30% of the total monomers; and / or During the preparation of the compound represented by the general formula (3), the diamine monomer forming the general formula (4) and the diamine monomer forming the general formula (5) account for a mass ratio of ≥60% of the total diamine monomers.

6. The photosensitive resin composition according to any one of claims 3 to 5, characterized in that, The diamine forming the general formula (4) is selected from the group consisting of the following structures:

7. And / or, the diamine structure forming the general formula (5) is as follows: 。 8. The photosensitive resin composition according to any one of claims 1 to 6, characterized in that, The (b) photosensitizer is an azidonaphthoquinone type photosensitizer; And / or, the (d) binder modifier is selected from one or more of the following: γ-glycidyletheroxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, p-aminophenyltrimethoxysilane, 3-(m-aminophenoxy)trimethoxysilane, 3-mercaptomethyltrimethoxysilane, 3-mercaptopropyltriethoxysilane; And / or, the (e) solvent is selected from one or more of ketone solvents, ester solvents, ether solvents, aromatic hydrocarbon solvents and other solvents.

9. The photosensitive resin composition according to any one of claims 1 to 7, characterized in that, The curing temperature of the photosensitive resin composition is ≤250 °C.

10. A photosensitive cured film, characterized in that, It is formed by curing the photosensitive resin composition according to any one of claims 1-8; Preferably, the average light transmittance of the photosensitive cured film at 380-780 nm is ≥70%; the thermal weight loss temperature T5% ≥300 °C.

11. The photosensitive curable film according to claim 9, characterized in that, The photosensitive cured film is applicable to the surface protection film and interlayer insulating film of semiconductor elements, the insulating layer of organic light-emitting elements and the insulating layer of thin-film transistors.

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