A negative photoresist composition, a method for preparing the same and use thereof

Abstract

The application provides a negative photoresist composition, a preparation method and application thereof. The negative photoresist composition comprises an acrylic copolymer resin, an acrylic monomer and a first initiator; the acrylic copolymer resin comprises a first structural unit, a second structural unit and a third structural unit. The negative photoresist composition has good anti-aging performance, high refractive index, high transmittance, high adhesion and high hardness.

Description

Technical Field

[0001] This invention relates to the field of optical materials technology, and in particular to a negative photoresist composition, its preparation method, and its application. Background Technology

[0002] In the field of optical materials technology, microlenses are important optical components widely used in display devices and image sensors. The main function of microlenses is to converge or diverge light to achieve precise control over light while simultaneously improving light transmittance. The properties of microlenses, such as refractive index, transmittance, and anti-aging properties, directly affect the performance of display devices and image sensors. Therefore, developing microlens materials with high refractive index, high transmittance, and excellent anti-aging properties is of great significance for improving the performance of display devices and image sensors.

[0003] Positive photoresist compositions contain the photosensitizer diazonoquinone. Due to the red color of the azo group in diazonoquinone, positive photoresist compositions have low light transmittance. Therefore, the formation of microlenses using negative photoresist compositions is a hot research topic; however, negative photoresist compositions have a relatively low refractive index.

[0004] Existing technologies primarily enhance the refractive index of acrylic resins by introducing specific functional groups, such as heteroatoms like sulfur and halogens, thereby increasing the refractive index of the negative photoresist composition. However, these methods lead to a decrease in the anti-aging properties of the acrylic resin and the negative photoresist composition it comprises, especially after high-temperature thermal aging, where its transmittance and anti-yellowing properties significantly decline. Furthermore, the adhesion and hardness of the negative photoresist composition also require further improvement.

[0005] Therefore, how to achieve high refractive index, high adhesion, and high hardness without sacrificing the anti-aging properties and light transmittance of negative photoresist compositions is a significant challenge currently facing the technology. Summary of the Invention

[0006] This invention provides a negative photoresist composition, its preparation method, and its application. The negative photoresist composition has good anti-aging properties, high refractive index, high transmittance, high adhesion, and high hardness, effectively overcoming the defects of the prior art.

[0007] This invention provides a negative photoresist composition comprising an acrylic copolymer resin, an acrylic monomer, and a first initiator; the acrylic copolymer resin comprises a first structural unit, a second structural unit, and a third structural unit; the first structural unit is shown in Formula 1:

[0008] Formula 1,

[0009] Wherein, R1 is selected from either hydrogen atom or methyl group, R2 and R3 are each independently selected from any one of the groups shown in Formula 1-1 and Formula 1-2, and n1 is any integer from 0 to 10.

[0010] Formula 1-1 Equation 1-2,

[0011] The second structural unit is shown in Equation 2:

[0012] Equation 2,

[0013] Wherein, R1 is selected from any one of hydrogen atoms and methyl groups, R2 is selected from any one of the groups shown in Formula 1-1 and Formula 1-2, R4 is selected from any one of carboxyl groups and hydroxyl groups, and n2 is any integer from 0 to 10.

[0014] Formula 1-1 Equation 1-2;

[0015] The structure of the third structural unit is shown in Equation 3:

[0016] Formula 3,

[0017] Wherein, R1 is selected from any one of hydrogen atoms and methyl groups, R2 is selected from any one of the groups shown in Formula 1-1 and Formula 1-2, R5 is selected from any one of the groups shown in Formula 3-1, Formula 3-1, and Formula 3-2, and n3 is any integer from 0 to 10.

[0018] Formula 1-1 Formula 1-2 Formula 3-1

[0019] Formula 3-2 Equation 3-3.

[0020] According to one embodiment of the present invention, the first structural unit includes one or more of the structural units shown in Formula 4-1, Formula 4-2, and Formula 4-3; and / or, the second structural unit includes one or more of the structural units shown in Formula 5-1, Formula 5-2, and Formula 5-3; and / or, the third structural unit includes one or more of the structural units shown in Formula 6-1, Formula 6-2, and Formula 6-3; and / or, the weight-average molecular weight of the acrylic copolymer resin is 500 g / mol to 100,000 g / mol; and / or, the acrylic copolymer resin accounts for 5% to 95% of the mass percentage of the negative photoresist composition.

[0021] According to one embodiment of the present invention, the acrylic copolymer resin is copolymerized from monomer raw materials including a first acrylate monomer, a second acrylate monomer, and a third acrylate monomer; preferably, the structure of the first acrylate monomer is shown in Formula 7; preferably, the structure of the second acrylate monomer is shown in Formula 8; preferably, the structure of the third acrylate monomer is shown in Formula 9; preferably, the first acrylate monomer accounts for 5% to 95% of the mass percentage of the monomer raw materials; preferably, the second acrylate monomer accounts for 5% to 95% of the mass percentage of the monomer raw materials; preferably, the third acrylate monomer accounts for 5% to 95% of the mass percentage of the monomer raw materials.

[0022] According to one embodiment of the present invention, the first acrylate monomer includes one or more compounds shown in Formula 10-1, Formula 10-2, and Formula 10-3; and / or, the second acrylate monomer includes one or more compounds shown in Formula 11-1, Formula 11-2, and Formula 11-3; and / or, the third acrylate monomer includes one or more compounds shown in Formula 12-1, Formula 12-2, and Formula 12-3.

[0023] According to one embodiment of the present invention, the acrylic monomer comprises a (meth)acrylate monomer containing at least two C=C groups; the negative photoresist composition satisfies: 0 < a ≤ 3, where a is the mass ratio of the acrylic monomer to the acrylic copolymer resin, preferably 0.5 ≤ a ≤ 2, more preferably 0.8 ≤ a ≤ 1.5; and / or, the first initiator comprises one or more of a photoinitiator, a thermal initiator, and a thermal acid generator; and / or, the negative photoresist composition satisfies: 0 < b ≤ 0.5, where b is the mass ratio of the first initiator to the acrylic copolymer resin, preferably 0.01 ≤ b ≤ 0.1; and / or, the negative photoresist composition further comprises one or more of additives and solvents, wherein the additives comprise one or more of a silane coupling agent and a leveling agent; preferably, the mass ratio of the additive to the acrylic copolymer resin is 0.001 to 0.1; preferably, the solvent comprises propylene glycol monomethyl ether acetate.

[0024] According to one embodiment of the present invention, the (meth)acrylate monomer containing at least two C=C groups includes one or more of the following: (meth)acrylate monomers containing two C=C groups, (meth)acrylate monomers containing three C=C groups, and (meth)acrylate monomers containing three or more C=C groups; and / or, the photoinitiator includes one or more of the following: O-acyl oxime compounds, azo compounds, azo ether compounds, acetophenone compounds, benzophenone compounds, quinone compounds, halogen compounds, and acyl phosphorus oxide compounds; and / or, the thermal initiator includes one or more of the following: peroxides and azo compounds; and / or, the thermal acid generator includes thionium salts.

[0025] Another aspect of the present invention provides a method for preparing the above-mentioned negative photoresist composition, comprising the following steps: mixing a first initiator, an acrylic monomer, and an acrylic copolymer resin to obtain the negative photoresist composition; preferably, the process of mixing the first initiator, the acrylic monomer, and the acrylic copolymer resin comprises: mixing the first initiator, the additive, the acrylic monomer, and the acrylic copolymer resin, and then adding a solvent thereto to obtain the negative photoresist composition.

[0026] Another aspect of the present invention provides a structural component comprising the above-described negative photoresist composition or a cured product formed by curing a negative photoresist composition prepared according to the above-described method for preparing the negative photoresist composition.

[0027] According to one embodiment of the present invention, the refractive index of the cured product is 1.55~1.65; and / or, the transmittance of the cured product after heat aging at 150±5 °C for 240±2 hours is greater than or equal to 95%.

[0028] Another aspect of the present invention provides a method for preparing the above-mentioned structural component, comprising the following steps: molding a negative photoresist composition to obtain a molded product; exposing and developing the molded product sequentially to obtain the structural component; wherein the developer comprises an alkaline solution.

[0029] The implementation of the present invention has at least the following beneficial effects: The negative photoresist composition of the present invention includes an acrylic copolymer resin, an acrylic monomer and a first initiator; the acrylic copolymer resin includes a first structural unit shown in Formula 1, a second structural unit shown in Formula 2 and a third structural unit shown in Formula 3, so that the negative photoresist composition has good anti-aging properties, high refractive index, high transmittance, high adhesion and high hardness. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0031] This invention provides a negative photoresist composition comprising an acrylic copolymer resin, an acrylic monomer, and a first initiator; the acrylic copolymer resin comprises a first structural unit, a second structural unit, and a third structural unit; the first structural unit is shown in Formula 1:

[0032] Formula 1,

[0033] Wherein, R1 is selected from either hydrogen atom or methyl group, R2 and R3 are each independently selected from any one of the groups shown in Formula 1-1 and Formula 1-2, and n1 is any integer from 0 to 10, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

[0034] Formula 1-1 Equation 1-2;

[0035] The second structural unit is shown in Equation 2:

[0036] Equation 2,

[0037] Wherein, R1 is selected from any one of hydrogen atoms and methyl groups, R2 is selected from any one of the groups shown in Formula 1-1 and Formula 1-2, R4 is selected from any one of carboxyl groups and hydroxyl groups, and n2 is any integer from 0 to 10, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

[0038] Formula 1-1 Equation 1-2;

[0039] The structure of the third structural unit is shown in Equation 3:

[0040] Formula 3;

[0041] Wherein, R1 is selected from any one of hydrogen atoms and methyl groups, R2 is selected from any one of the groups shown in Formula 1-1 and Formula 1-2, R5 is selected from any one of the groups shown in Formula 3-1, Formula 3-2, and Formula 3-3, and n3 is any integer from 0 to 10, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

[0042] Formula 1-1 Formula 1-2 Formula 3-1

[0043] Formula 3-2 Equation 3-3.

[0044] For example, an acrylic copolymer resin may include the compound shown in Formula 13:

[0045] Equation 13,

[0046] In this formula, R1 is selected from any one of hydrogen atoms and methyl groups; R2 and R3 are each independently selected from any one of the groups shown in Formula 1-1 and Formula 1-2; R4 is selected from any one of carboxyl groups and hydroxyl groups; R5 is selected from any one of the groups shown in Formula 3-1, Formula 3-2, and Formula 3-3; n1 is any integer from 0 to 10, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10; n2 is any integer from 0 to 10, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10; and n3 is any integer from 0 to 10, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

[0047] Formula 1-1 Formula 1-2 Formula 3-1

[0048] Formula 3-2 Equation 3-3.

[0049] According to the inventors' research, acrylic copolymer resins containing first, second, and third structural units can increase the refractive index of negative photoresist compositions, thereby improving the performance of display devices and image sensors. This allows for more precise control of light convergence and divergence, resulting in improved image quality and display effects. Secondly, acrylic copolymer resins containing first, second, and third structural units can give negative photoresist compositions excellent transmittance, maintaining high transmittance even after high-temperature thermal aging, which helps extend the lifespan of display devices and image sensors.

[0050] The first, second, and third structural units are repeating units of an acrylic copolymer resin, each containing aromatic groups such as benzene rings. The first structural unit primarily functions to adjust the refractive index, giving the negative photoresist composition a higher refractive index. The second structural unit mainly functions to adjust the development, which is beneficial for improving the performance of display devices and image sensors. The third structural unit's main function is curable crosslinking, increasing the hardness and chemical solvent resistance of the acrylic copolymer resin, thereby enhancing the anti-aging properties and hardness of the negative photoresist composition.

[0051] The negative photoresist composition in this embodiment of the invention includes a first initiator, an acrylic monomer, and an acrylic copolymer resin containing a first structural unit, a second structural unit, and a third structural unit. The negative photoresist composition has good anti-aging properties, high refractive index, high adhesion, and high hardness. Specifically, the cured product of the negative photoresist composition has good anti-aging properties, high refractive index, high adhesion, and high hardness.

[0052] In some embodiments, the first structural unit includes one or more of the structural units shown in Equations 4-1, 4-2, and 4-3:

[0053] Formula 4-1

[0054] Equation 4-2,

[0055] Equation 4-3;

[0056] The second structural unit includes one or more of the structural units shown in Equations 5-1, 5-2, and 5-3:

[0057] Formula 5-1 Formula 5-2

[0058] Equation 5-3;

[0059] The third structural unit includes one or more of the structural units shown in Equations 6-1, 6-2, and 6-3:

[0060] Formula 6-1 Formula 6-2

[0061] Equation 6-3.

[0062] In some embodiments, the weight-average molecular weight of the acrylic copolymer resin is 500 g / mol to 100,000 g / mol, for example, 500 g / mol, 1,000 g / mol, 5,000 g / mol, 10,000 g / mol, 20,000 g / mol, 50,000 g / mol, 80,000 g / mol, 100,000 g / mol, or any combination thereof, which is beneficial for the curing of the negative photoresist composition.

[0063] In some embodiments, the acrylic copolymer resin accounts for 5% to 95% of the negative photoresist composition by mass, for example, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, or any combination thereof, which is beneficial for the negative photoresist composition to have both good anti-aging properties and high transmittance and refractive index.

[0064] In some embodiments, the acrylic copolymer resin is copolymerized from monomer raw materials including a first acrylate monomer, a second acrylate monomer, and a third acrylate monomer.

[0065] The first acrylate monomer, the second acrylate monomer, and the third acrylate monomer all contain unsaturated bonds, specifically carbon-carbon double bonds. In the copolymerization reaction, the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer copolymerize through carbon-carbon double bonds to form an acrylic copolymer resin. The first acrylate monomer, the second acrylate monomer, and the third acrylate monomer respectively form the first structural unit, the second structural unit, and the third structural unit in the acrylic copolymer resin.

[0066] In some embodiments, the structure of the first acrylate monomer is as shown in Formula 7, used to form the first structural unit:

[0067] Equation 7,

[0068] Wherein, R1 is selected from either hydrogen atom or methyl group, R2 and R3 are each independently selected from any one of the groups shown in Formula 1-1 and Formula 1-2, and n1 is any integer from 0 to 10, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

[0069] Formula 1-1 Equation 1-2;

[0070] The structure of the second acrylate monomer is shown in Formula 8, and it is used to form the second structural unit:

[0071] Formula 8,

[0072] Wherein, R1 is selected from any one of hydrogen atoms and methyl groups, R2 is selected from any one of the groups shown in Formula 1-1 and Formula 1-2, R4 is selected from any one of carboxyl groups and hydroxyl groups, and n2 is any integer from 0 to 10, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

[0073] Formula 1-1 Equation 1-2;

[0074] The structure of the third acrylate monomer is shown in Formula 9, and it is used to form the third structural unit:

[0075] Formula 9,

[0076] Wherein, R1 is selected from any one of hydrogen atoms and methyl groups, R2 is selected from any one of the groups shown in Formula 1-1 and Formula 1-2, R5 is selected from any one of the groups shown in Formula 3-1, Formula 3-2, and Formula 3-3, and n3 is any integer from 0 to 10, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

[0077] Formula 1-1 Formula 1-2 Formula 3-1

[0078] Formula 3-2 Equation 3-3.

[0079] In some embodiments, the first acrylate monomer accounts for 5% to 95% of the monomer raw material by mass, for example, 5%, 6%, 9%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 85%, 86%, 88%, 90%, 92%, 95%, or any combination thereof.

[0080] In addition, the second acrylate monomer accounts for 5% to 95% of the monomer raw material by mass, for example, 5%, 6%, 9%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 85%, 86%, 88%, 90%, 92%, 95%, or any combination thereof.

[0081] In addition, the third acrylate monomer accounts for 5% to 95% of the monomer raw material by mass, for example, 5%, 6%, 9%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 85%, 86%, 88%, 90%, 92%, 95%, or any combination thereof.

[0082] In some embodiments, the first acrylate monomer comprises one or more compounds shown in Formula 10-1, Formula 10-2, and Formula 10-3:

[0083] Formula 10-1

[0084] Formula 10-2

[0085] Equation 10-3;

[0086] The second acrylate monomer includes one or more of the compounds shown in Formula 11-1, Formula 11-2, and Formula 11-3:

[0087] Formula 11-1 Formula 11-2

[0088] Equation 11-3;

[0089] The third acrylate monomer includes one or more of the compounds shown in Formula 12-1, Formula 12-2, and Formula 12-3:

[0090] Formula 12-1 Equation 12-2

[0091] Equation 12-3.

[0092] In some embodiments, the acrylic monomers include (meth)acrylate monomers containing at least two C=C groups, which is beneficial for further improving the anti-aging properties and adhesion of the negative photoresist composition.

[0093] Furthermore, the negative photoresist composition satisfies the following condition: 0 < a ≤ 3, where a is the mass ratio of acrylic monomer to acrylic copolymer resin, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 18, 2, 2.5, 3 or any combination thereof, preferably 0.5 ≤ a ≤ 2, and more preferably 0.8 ≤ a ≤ 1.5, which is beneficial for forming a negative photoresist composition with high mechanical strength and excellent adhesion.

[0094] In some embodiments, the first initiator includes one or more of a photoinitiator, a thermal initiator, and a thermal acid generator.

[0095] In specific implementation, the negative photoresist composition satisfies the following condition: 0 < b ≤ 0.5, where b is the mass ratio of the first initiator to the acrylic copolymer resin, for example, a range of 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, or any combination thereof, preferably 0.01 ≤ b ≤ 0.1, which is beneficial for improving the heat resistance, solvent resistance, and pattern shape controllability of the negative photoresist composition after development.

[0096] In some embodiments, the negative photoresist composition further includes one or more additives and solvents, wherein the additives include one or more silane coupling agents and leveling agents.

[0097] In some embodiments, the mass ratio of the additive to the acrylic copolymer resin is 0.001 to 0.1, for example, a range of 0.001, 0.002, 0.003, 0.004, 0.005, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, or any combination thereof.

[0098] Specifically, the silane coupling agent includes one or more of the following: silane coupling agents having a carboxyl group, silane coupling agents having a methylpropyl acyl group, silane coupling agents having an isocyanate group, and silane coupling agents having an epoxy group. For example, it may include one or more of the following: trimethoxysilylbenzoic acid, γ-methacryloyloxypropyltrimethoxysilane, vinyltriacetylsilane, vinyltrimethoxysilane, γ-isocyanatepropyltriethoxysilane, γ-epoxypropoxypropyltrimethoxysilane, and 2-(3',4'-epoxycyclohexyl)ethyltrimethoxysilane.

[0099] Furthermore, the mass ratio of the silane coupling agent to the acrylic copolymer resin is 0 to 0.1, for example, 0.001, 0.002, 0.003, 0.004, 0.005, 0.01, 0.02, 0.03, 0.04, 0.05, 0.08, 0.1, or any combination thereof, preferably 0.001 to 0.05, to improve the adhesion between the cured product of the photoresist composition and the substrate.

[0100] In practice, leveling agents include one or more of fluorinated surfactants and silicone surfactants. Examples include BYK-333 (manufactured by BYKCHEMIE Co., Ltd.), R-08 (manufactured by DIC Corporation), R-475 (manufactured by DIC Corporation), R-30 (manufactured by DIC Corporation), BM-1000 (manufactured by BMCHEMIE Corporation), BM-1100 (manufactured by BMCHEMIE Corporation), FLUORADE FC-135 (manufactured by Sumitomo 3M Co., Ltd.), FLUORADE FC-170C (manufactured by Sumitomo 3M Co., Ltd.), FLUORADE FC-430 (manufactured by Sumitomo 3M Co., Ltd.), FLUORADE FC-431 (manufactured by Sumitomo 3M Co., Ltd.), SAFLON S-112 (manufactured by Asahi Glass Co., Ltd.), SAFLON S-113 (manufactured by Asahi Glass Co., Ltd.), SAFLON S-131 (manufactured by Asahi Glass Co., Ltd.), and SAFLON... S-141 (manufactured by Asahi Glass Co., Ltd.), SAFLON S-145 (manufactured by Asahi Glass Co., Ltd.), SAFLON S-382 (manufactured by Asahi Glass Co., Ltd.), SAFLON SC-101 (manufactured by Asahi Glass Co., Ltd.), SAFLON SC-102 (manufactured by Asahi Glass Co., Ltd.), SAFLON SC-103 (manufactured by Asahi Glass Co., Ltd.), SAFLON SC-104 (manufactured by Asahi Glass Co., Ltd.), SAFLON SC-105 (manufactured by Asahi Glass Co., Ltd.), SAFLON One or more of the following: SC-106 (manufactured by Asahi Glass Co., Ltd.), SH-28PA (manufactured by Toray Silicone Co., Ltd.), SH-190 (manufactured by Toray Silicone Co., Ltd.), SH-193 (manufactured by Toray Silicone Co., Ltd.), SZ-6032 (manufactured by Toray Silicone Co., Ltd.), SF-8428 (manufactured by Toray Silicone Co., Ltd.), DC-57 (manufactured by Toray Silicone Co., Ltd.), and DC190 (manufactured by Toray Silicone Co., Ltd.). Furthermore, the mass ratio of the leveling agent to the acrylic copolymer resin is 0.001 to 0.05, preferably 0.001 to 0.02, for example, within the range of 0.001, 0.002, 0.003, 0.004, 0.005, 0.01, 0.02, or any combination thereof, which facilitates the coating of the negative photoresist composition onto the substrate.

[0101] In some embodiments, the solvent includes an organic solvent, such as propylene glycol monomethyl ether acetate.

[0102] In some embodiments, (meth)acrylate monomers containing at least two C=C groups include one or more of (meth)acrylate monomers containing two C=C groups, (meth)acrylate monomers containing three C=C groups, and (meth)acrylate monomers containing more than three C=C groups.

[0103] Generally, the number of C=C groups in (meth)acrylate monomers containing at least two C=C groups is not particularly limited. However, (meth)acrylate monomers containing two or more C=C groups and (meth)acrylate monomers containing three or more C=C groups have good reactivity, which is beneficial to the curing of negative photoresist compositions and results in higher strength of the cured negative photoresist compositions. Therefore, (meth)acrylate monomers containing two or more C=C groups and (meth)acrylate monomers containing three or more C=C groups are preferred, and (meth)acrylate monomers containing three or more C=C groups are even more preferred.

[0104] In this invention, (meth)acrylate monomers include methacrylate monomers and / or acrylate monomers.

[0105] Specifically, (meth)acrylate monomers containing two C=C groups include one or more of the following: ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol diacrylate, 1,9-nonanediol dimethacrylate, bisphenoxyethanol fluorene diacrylate, and bisphenoxyethanol fluorene dimethacrylate.

[0106] (Meth)acrylate monomers containing three C=C groups include one or more of trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, and pentaerythritol trimethacrylate.

[0107] (Meth)acrylate monomers containing three or more C=C groups include one or more of pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, tris(2-acryloyloxyethyl) phosphate, and tris(2-methacryloyloxyethyl) phosphate.

[0108] In some embodiments, the photoinitiator includes one or more of the following: O-acyl oxime compounds, acetoin compounds, acetoin ether compounds, acetophenone compounds, benzophenone compounds, quinone compounds, halogen compounds, and acyl phosphorus oxide compounds.

[0109] In specific implementations, O-acyl oxime compounds include acetophenone-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-1-(O-acetyl oxime), acetophenone-1-[9-ethyl-6-[2-methyl-4-(2,2-dimethyl-1,3-dioxolane)methoxybenzoyl]-9H-carbazole-3-yl]-1-(O-acetyl oxime), 1-[9-ethyl-6-benzoyl-9H-carbazole-3-yl]-1,2-nonane-2-oxime-O-benzoate, 1-[9-ethyl-6- [benzoyl-9H-carbazole-3-yl]-1,2-nonane-2-oxime-O-acetate, 1-[9-ethyl-6-benzoyl-9H-carbazole-3-yl]-1,2-pentane-2-oxime-O-acetate, 1-[9-ethyl-6-benzoyl-9H-carbazole-3-yl]-octane-1-one oxime-O-acetate, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-ethane-1-one oxime-O-benzoate, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-ethane-1-one oxime-O-benzoate One or more of H-carbazole-3-yl]-ethane-1-one oxime-O-acetate and 1-[9-n-butyl-6-(2-ethylbenzoyl)-9H-carbazole-3-yl]-ethane-1-one oxime-O-benzoate; acinin compounds including one or more of benzoin and anisolein; acinin ether compounds including one or more of benzoin methyl ether, benzoin ethyl ether, and benzoin-propyl ether; acetophenone compounds including acetophenone, p-dimethylaminoacetophenone, and 2-hydroxy-1,2-di(2-methylphenyl)ethyl acetophenone. Ketones, p-methoxyacetophenone; benzophenone compounds include one or more of α,α'-dimethoxyacetic acid benzophenone and 4,4-bis-(diethylamino)-benzophenone; quinone compounds include one or more of anthraquinone and 1,4-naphthoquinone; halogen compounds include one or more of benzoylmethyl chloride, tribromomethyl sulfone, and tris(trichloromethyl)-s-triazine; acyl phosphorus oxides include one or more of 2,4,6-trimethylbenzoyl diphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

[0110] In some embodiments, the thermal initiator includes one or more of peroxides and azo compounds, wherein the peroxide compound includes one or more of benzoyl peroxide and di-tert-butyl peroxide, and the azo compound includes azobisisobutyl cyanide.

[0111] In practice, the hot acid generating agent includes thionium salts.

[0112] The present invention also provides a method for preparing the above-mentioned negative photoresist composition, comprising the following steps: mixing a first initiator, an acrylic monomer and an acrylic copolymer resin to obtain a negative photoresist composition.

[0113] In some embodiments, the process of mixing the first initiator, acrylic monomer, and acrylic copolymer resin includes: mixing the first initiator, additive, acrylic monomer, and acrylic copolymer resin, and then adding a solvent thereto to obtain a negative photoresist composition.

[0114] In specific implementation, a first acrylate monomer, a second acrylate monomer, and a third acrylate monomer are first synthesized; then, the monomer raw materials including the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are copolymerized under the action of a second initiator to obtain an acrylic copolymer resin; the first initiator, additives, acrylic monomers, and acrylic copolymer resin are mixed, and a solvent is added to obtain a mixture. The viscosity of the mixture is controlled to be 3 cPs-20 cPs, for example, 3 cPs, 5 cPs, 8 cPs, 10 cPs, 13 cPs, 15 cPs, 18 cPs, 20 cPs, or any combination thereof, to obtain a negative photoresist composition.

[0115] The second initiator includes one or more of azo compounds and peroxides. The azo compounds include one or more of azobisisobutyronitrile and azobisisoheptanecyanide, and the peroxides include benzoyl peroxide.

[0116] The present invention also provides a structural component comprising the above-described negative photoresist composition or a cured product formed by curing a negative photoresist composition prepared according to the above-described method for preparing the negative photoresist composition.

[0117] In some embodiments, the refractive index of the cured product is 1.55 to 1.65, for example, a range of 1.55, 1.56, 1.57, 1.58, 1.59, 1.60, 1.61, 1.62, 1.63, 1.64, 1.65 or any combination thereof.

[0118] In addition, the transmittance of the cured product after heat aging at 150±5 ℃ for 240±2 hours is greater than or equal to 95%, for example, greater than or equal to 95%, greater than or equal to 96%, greater than or equal to 97%, greater than or equal to 98%, greater than or equal to 99%, greater than or equal to 99.5%, or any combination thereof.

[0119] The present invention also provides a method for preparing the above-mentioned structural component, comprising the following steps: molding a negative photoresist composition to obtain a molded product; exposing and developing the molded product sequentially to obtain the structural component; wherein the developer includes an alkaline solution.

[0120] In practice, the negative photoresist composition is shaped and exposed, and then developed with a developer. During the exposure process, the negative photoresist composition undergoes a solidification reaction, and the unexposed areas are dissolved and removed by the developer, leaving a negative image of the exposed areas.

[0121] The present invention will be further described below through specific embodiments.

[0122] Example 1

[0123] 1. Synthesis of the first acrylate monomer

[0124] After preparing a flask equipped with a mechanical stirrer, thermometer, and cooling jacket, 240 g of tetrahydrofuran, 26.5 g of 1,3,5-tristobenzoyl chloride, and 30.0 g of triethylamine were added under a nitrogen atmosphere. After purging the flask jacket with cooling water at 5°C, 13.0 g of hydroxyethyl methacrylate was gradually added dropwise to the flask, and the mixture was kept at room temperature for 2 hours. Then, 34.0 g of p-hydroxybiphenyl was added to the flask, and the reaction was continued for 12 hours. The mixture was filtered to obtain a clear solution. The clear solution was then precipitated in water, and the precipitate was dried in a vacuum drying oven to obtain the compound shown in Formula 10-1.

[0125] 2. Synthesis of the second acrylate monomer

[0126] After preparing a flask equipped with a mechanical stirrer, thermometer, and cooling jacket, 240 g of tetrahydrofuran, 26.5 g of 1,3,5-tristobenzoyl chloride, and 10.0 g of triethylamine were added under a nitrogen atmosphere. After purging the flask jacket with cooling water at 5°C, 13.0 g of hydroxyethyl methacrylate was gradually added dropwise to the flask. The mixture was then kept at room temperature for 2 hours, filtered, and a clear solution was obtained. The clear solution was then precipitated in water, and the precipitate was dried in a vacuum drying oven to obtain the compound shown in Formula 11-1.

[0127] 3. Synthesis of the third acrylate monomer

[0128] After preparing a flask equipped with a mechanical stirrer, thermometer, and cooling jacket, 240 g of tetrahydrofuran, 12.6 g of phloroglucinol, and 30.0 g of triethylamine were added under a nitrogen atmosphere. The flask jacket was then purged with cooling water at 5°C. 10.4 g of methacrylamide chloride was then added dropwise to the flask, and the mixture was kept at room temperature for 2 hours. Next, 18.4 g of epichlorohydrin was added, and the mixture was heated to 100°C and stirred for 1 hour. The mixture was filtered to obtain a clear solution. The clear solution was then precipitated in water, and the precipitate was dried in a vacuum drying oven to obtain the compound shown in Formula 12-1.

[0129] 4. Synthesis of acrylic copolymer resins

[0130] 10.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, 5.0 g of the compound shown in Formula 12-1, 0.2 g of azobisisobutyronitrile, and 80.0 g of solvent propylene glycol monomethyl ether acetate (PGMEA) were placed in a jacketed reactor, nitrogen was introduced to purge oxygen, the temperature was raised to 65°C, and the reaction was carried out for 24 h with stirring to obtain an acrylic copolymer resin solution.

[0131] 5. Formulation of negative photoresist composition

[0132] Add 100 parts by weight of acrylic copolymer resin (calculated by the mass of acrylic copolymer resin in the acrylic copolymer resin solution), 50 parts by weight of trimethylolpropane triacrylate (product name: TMPTA, Nippon Kayaku Co., Ltd.), 40 parts by weight of dipentaerythritol pentaacrylate (product name: SR-399NS, Sartoma Co., Ltd.), 3 parts by weight of acetone-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-1-(O-acetyl oxime) (product name: OXE-02, BASF Co., Ltd.), 5 parts by weight of 4,4-bis-(diethylamino)-benzophenone (product name: Hycure EMK, KEMAX Co., Ltd.), 1 part by weight of γ-glycidoxypropyltrimethoxysilane, and 0.5 parts by weight of BYK-333 to a mixing tank equipped with an ultraviolet blocking membrane and a stirrer, and add propylene glycol monomethyl ether acetate as solvent to form a mixture. The solvent volume was adjusted to achieve a viscosity of 15 cPs for the mixture. After the above components were mixed evenly, the mixture was filtered through a microporous filter with a pore size of 0.45 μm to prepare a negative photoresist composition, wherein the acrylic copolymer resin accounted for 10.5% of the mass percentage of the negative photoresist composition.

[0133] Example 2

[0134] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 5.0 g of the compound shown in Formula 10-1, 10.0 g of the compound shown in Formula 11-1, and 5.0 g of the compound shown in Formula 12-1, while keeping other conditions the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0135] Example 3

[0136] 1. Synthesis of the first acrylate monomer

[0137] After preparing a flask equipped with a mechanical stirrer, thermometer, and cooling jacket, 240 g of tetrahydrofuran, 26.1 g of 1,3,5-triphenyl isocyanate, and 0.1 g of dibutyltin dilaurate were added under a nitrogen atmosphere. The temperature of the flask was then raised to 65°C, and 13.0 g of hydroxyethyl methacrylate was added dropwise to the flask. The reaction was maintained at 65°C for 2 hours. Then, 34.0 g of p-hydroxybiphenyl was added to the flask, and the reaction was continued at 65°C for 12 hours to obtain a reaction solution. The reaction solution was then precipitated in water, and the precipitate was dried in a vacuum drying oven to obtain the compound shown in Formula 10-2.

[0138] 2. Synthesis of the second acrylate monomer

[0139] After preparing a flask equipped with a mechanical stirrer, thermometer, and cooling jacket, 240 g of tetrahydrofuran, 12.6 g of phloroglucinol, and 10.0 g of triethylamine were added under a nitrogen atmosphere. The flask jacket was then purged with cooling water at 5°C. 10.4 g of methacrylamide chloride was then added dropwise to the flask. The mixture was kept at room temperature for 2 hours, filtered, and a clear solution was obtained. This clear solution was then precipitated in water, and the precipitate was dried in a vacuum drying oven to obtain the compound shown in Formula 11-2.

[0140] 3. Synthesis of the third acrylate monomer

[0141] After preparing a flask equipped with a mechanical stirrer, thermometer, and cooling jacket, 240 g of tetrahydrofuran, 12.6 g of phloroglucinol, and 0.1 g of dibutyltin dilaurate were added under a nitrogen atmosphere. The temperature of the flask was then raised to 65°C. 15.5 g of isocyanate methacrylate was then added dropwise to the flask, and the reaction was maintained at 65°C for 2 hours. Next, 18.4 g of epichlorohydrin was added, and the mixture was heated to 100°C and stirred for 1 hour to obtain a reaction solution. The reaction solution was then dissolved in water to obtain a precipitate, which was then dried in a vacuum drying oven to obtain the compound shown in Formula 12-2.

[0142] 4. Synthesis of acrylic copolymer resins

[0143] 10.0 g of the compound shown in Formula 10-2, 5.0 g of the compound shown in Formula 11-2, 5.0 g of the compound shown in Formula 12-2, 0.2 g of azobisisobutyronitrile, and 80.0 g of solvent PGMEA were placed in a jacketed reactor, nitrogen gas was introduced to remove oxygen, the temperature was raised to 65°C, and the reaction was carried out for 24 h with stirring to obtain an acrylic copolymer resin solution.

[0144] 5. Formulation of negative photoresist composition

[0145] Add 100 parts by weight of acrylic copolymer resin (calculated by the mass of acrylic copolymer resin in the acrylic copolymer resin solution), 50 parts by weight of trimethylolpropane triacrylate (product name: TMPTA, Nippon Kayaku Co., Ltd.), 40 parts by weight of dipentaerythritol pentaacrylate (product name: SR-399NS, Sartoma Co., Ltd.), 3 parts by weight of acetone-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-1-(O-acetyl oxime) (product name: OXE-02, BASF Co., Ltd.), 5 parts by weight of 4,4-bis-(diethylamino)-benzophenone (product name: Hycure EMK, KEMAX Co., Ltd.), 1 part by weight of γ-glycidoxypropyltrimethoxysilane, and 0.5 parts by weight of BYK-333 to a mixing tank equipped with an ultraviolet blocking membrane and a stirrer, and add propylene glycol monomethyl ether acetate as solvent to form a mixture. The solvent volume was adjusted to achieve a viscosity of 15 cPs for the mixture. After the above components were mixed evenly, the mixture was filtered through a microporous filter with a pore size of 0.45 μm to prepare a negative photoresist composition, wherein the acrylic copolymer resin accounted for 10.5% of the mass percentage of the negative photoresist composition.

[0146] Example 4

[0147] The difference from Example 3 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 5.0 g of the compound shown in Formula 10-2, 10.0 g of the compound shown in Formula 11-2, and 5.0 g of the compound shown in Formula 12-2, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0148] Example 5

[0149] 1. Synthesis of the first acrylate monomer

[0150] After preparing a flask equipped with a mechanical stirrer, thermometer, and cooling jacket, 240 g of tetrahydrofuran, 12.6 g of phloroglucinol, and 0.1 g of dibutyltin dilaurate were added under a nitrogen atmosphere. The reactor temperature was then raised to 65°C. 15.5 g of isocyanate methacrylate was gradually added dropwise to the flask, and the reaction was maintained at 65°C for 2 hours. Then, 39.0 g of 4-biphenyl isocyanate was added to the reactor, and the reaction was continued at 65°C for 12 hours to obtain a reaction solution. The reaction solution was then added to water, and after precipitating with water, the precipitate was dried in a vacuum drying oven to obtain the compound shown in Formula 10-3.

[0151] 2. Synthesis of the second acrylate monomer

[0152] After preparing a flask equipped with a mechanical stirrer, thermometer, and cooling jacket, 240 g of tetrahydrofuran, 12.6 g of phloroglucinol, and 0.1 g of dibutyltin dilaurate were added under a nitrogen atmosphere. The temperature of the flask was then raised to 65°C, and 15.5 g of isocyanate methacrylate was gradually added dropwise to the flask. The reaction was maintained at 65°C for 2 hours to obtain a reaction solution. The reaction solution was then precipitated in water, and the precipitate was dried in a vacuum drying oven to obtain the compound shown in Formula 11-3.

[0153] 3. Synthesis of the third acrylate monomer

[0154] After preparing a flask equipped with a mechanical stirrer, thermometer, and cooling jacket, 240 g of tetrahydrofuran, 26.5 g of 1,3,5-tristobenzoyl chloride, and 30.0 g of triethylamine were added under a nitrogen atmosphere. After purging the flask jacket with cooling water at 5°C, 13.0 g of hydroxyethyl methacrylate was gradually added dropwise to the flask, and the mixture was kept at room temperature for 2 hours. Then, 14.8 g of glycidol was added to the flask, and the mixture was stirred at room temperature for 12 hours. The mixture was filtered to obtain a clear solution. The clear solution was then precipitated in water, and the precipitate was dried in a vacuum drying oven to obtain the compound shown in Formula 12-3.

[0155] 4. Synthesis of acrylic copolymer resins

[0156] 10.0 g of the compound shown in Formula 10-3, 5.0 g of the compound shown in Formula 11-3, 5.0 g of the compound shown in Formula 12-3, 0.2 g of azobisisobutyronitrile, and 80.0 g of solvent PGMEA were placed in a jacketed reactor, nitrogen gas was introduced to remove oxygen, the temperature was raised to 65°C, and the reaction was carried out for 24 h with stirring to obtain an acrylic copolymer resin solution.

[0157] 5. Formulation of negative photoresist composition

[0158] Add 100 parts by weight of acrylic copolymer resin (calculated by the mass of acrylic copolymer resin in the acrylic copolymer resin solution), 50 parts by weight of trimethylolpropane triacrylate (product name: TMPTA, Nippon Kayaku Co., Ltd.), 40 parts by weight of dipentaerythritol pentaacrylate (product name: SR-399NS, Sartoma Co., Ltd.), 3 parts by weight of acetone-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-1-(O-acetyl oxime) (product name: OXE-02, BASF Co., Ltd.), 5 parts by weight of 4,4-bis-(diethylamino)-benzophenone (product name: Hycure EMK, KEMAX Co., Ltd.), 1 part by weight of γ-glycidoxypropyltrimethoxysilane, and 0.5 parts by weight of BYK-333 to a mixing tank equipped with an ultraviolet blocking membrane and a stirrer, and add propylene glycol monomethyl ether acetate as solvent to form a mixture. The solvent volume was adjusted to achieve a viscosity of 15 cPs for the mixture. After the above components were mixed evenly, the mixture was filtered through a microporous filter with a pore size of 0.45 μm to prepare a negative photoresist composition, wherein the acrylic copolymer resin accounted for 10.5% of the mass percentage of the negative photoresist composition.

[0159] Example 6

[0160] The difference from Example 5 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 5.0 g of the compound shown in Formula 10-3, 10.0 g of the compound shown in Formula 11-3, and 5.0 g of the compound shown in Formula 12-3, while keeping other conditions the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0161] Example 7

[0162] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 30.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, and 5.0 g of the compound shown in Formula 12-1, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0163] Example 8

[0164] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 40.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, and 5.0 g of the compound shown in Formula 12-1, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0165] Example 9

[0166] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 2.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, and 5.0 g of the compound shown in Formula 12-1, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0167] Example 10

[0168] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 1.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, and 5.0 g of the compound shown in Formula 12-1, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0169] Example 11

[0170] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 10.0 g of the compound shown in Formula 10-1, 45.0 g of the compound shown in Formula 11-1, and 5.0 g of the compound shown in Formula 12-1, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0171] Example 12

[0172] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 10.0 g of the compound shown in Formula 10-1, 60.0 g of the compound shown in Formula 11-1, and 5.0 g of the compound shown in Formula 12-1, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0173] Example 13

[0174] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 10.0 g of the compound shown in Formula 10-1, 2.0 g of the compound shown in Formula 11-1, and 5.0 g of the compound shown in Formula 12-1, while keeping other conditions the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0175] Example 14

[0176] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 10.0 g of the compound shown in Formula 10-1, 1.0 g of the compound shown in Formula 11-1, and 5.0 g of the compound shown in Formula 12-1, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0177] Example 15

[0178] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 10.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, and 45.0 g of the compound shown in Formula 12-1, while keeping other conditions the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0179] Example 16

[0180] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 10.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, and 60.0 g of the compound shown in Formula 12-1, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0181] Example 17

[0182] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 10.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, and 2.0 g of the compound shown in Formula 12-1, while keeping other conditions the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0183] Example 18

[0184] The difference from Example 1 is that the amounts of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer are changed to: 10.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, and 1.0 g of the compound shown in Formula 12-1, while keeping other conditions the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0185] Example 19

[0186] The difference from Example 1 is that the mass fraction of trimethylolpropane triacrylate and the mass fraction of dipentaerythritol pentaacrylate are changed to 150, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 5% of the mass fraction of the negative photoresist composition.

[0187] Example 20

[0188] The difference from Example 1 is that the mass fraction of trimethylolpropane triacrylate is changed to 200 and the mass fraction of dipentaerythritol pentaacrylate is changed to 200, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 4% of the negative photoresist composition by mass.

[0189] Example 21

[0190] The difference from Example 1 is that the synthesis process of the acrylic copolymer resin in step 4 is as follows:

[0191] 10.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, 5.0 g of the compound shown in Formula 12-1, 0.2 g of azobisisobutyronitrile (AIBN), and 80.0 g of propylene glycol monomethyl ether acetate (PGMEA) solvent were placed in a jacketed reactor. Nitrogen gas was introduced to purge oxygen, and the temperature was raised to 65°C. The reaction was carried out with stirring for 5 h to obtain an acrylic copolymer resin solution. Other conditions were kept consistent. The acrylic copolymer resin accounted for 10.5% of the mass percentage of the negative photoresist composition.

[0192] Example 22

[0193] The difference from Example 1 is that the synthesis process of the acrylic copolymer resin in step 4 is as follows:

[0194] 10.0 g of the compound shown in Formula 10-1, 5.0 g of the compound shown in Formula 11-1, 5.0 g of the compound shown in Formula 12-1, 0.2 g of azobisisobutyronitrile (AIBN), and 80.0 g of propylene glycol monomethyl ether acetate (PGMEA) solvent were placed in a jacketed reactor. Nitrogen gas was introduced to purge oxygen, and the temperature was raised to 65°C. The reaction was carried out with stirring for 48 h to obtain an acrylic copolymer resin solution. Other conditions were kept consistent. The acrylic copolymer resin accounted for 10.5% of the mass percentage of the negative photoresist composition.

[0195] Comparative Example 1

[0196] The difference from Example 1 is that the first acrylate monomer is not added, but 10.0 g of methyl methacrylate (MMA) is added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0197] Comparative Example 2

[0198] The difference from Example 2 is that the first acrylate monomer is not added, but 5.0 g of methyl methacrylate (MMA) is added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0199] Comparative Example 3

[0200] The difference from Example 3 is that the first acrylate monomer is not added, but 10.0 g of methyl methacrylate (MMA) is added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0201] Comparative Example 4

[0202] The difference from Example 4 is that the first acrylate monomer is not added, but 5.0 g of methyl methacrylate (MMA) is added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0203] Comparative Example 5

[0204] The difference from Example 5 is that the first acrylate monomer is not added, but 10.0 g of methyl methacrylate (MMA) is added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0205] Comparative Example 6

[0206] The difference from Example 6 is that the first acrylate monomer is not added, but 5.0 g of methyl methacrylate (MMA) is added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0207] Comparative Example 7

[0208] The difference from Example 1 is that the first acrylate monomer is not added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0209] Comparative Example 8

[0210] The difference from Example 1 is that no second acrylate monomer is added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0211] Comparative Example 9

[0212] The difference from Example 1 is that no third acrylate monomer is added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 10.5% of the mass percentage of the negative photoresist composition.

[0213] Comparative Example 10

[0214] The difference from Example 1 is that no acrylic monomers are added, while other conditions remain the same, wherein the acrylic copolymer resin accounts for 20% of the mass percentage of the negative photoresist composition.

[0215] Table 1 summarizes the types and masses of the first acrylate monomer, the types and masses of the second acrylate monomer, the types and masses of the third acrylate monomer, the weight-average molecular weight of the acrylic copolymer resin, and the types and masses of acrylic monomers in each embodiment and comparative example.

[0216] The performance of the prepared negative photoresist composition was tested using the following procedures, and the results are shown in Table 2:

[0217] (1) Evaluation of refractive index

[0218] After spin-coating a negative photoresist composition onto a silicon wafer substrate, the coated surface was pre-dried by heating (at 100°C for 90 seconds). Without exposure through a photomask, it was developed in a tetramethylammonium hydroxide (TMAH) aqueous solution at 25°C for 60 seconds, rinsed with pure water for 1 minute, and then cured in an oven at 230°C for 30 minutes. The refractive index of the cured product was measured using an ellipsometer at a wavelength of 550 nm.

[0219] Evaluation criteria: ◎: Excellent, ●: Good, ▲: Average, X: Poor. Based on refractive index data, the evaluation is as follows: ◎: Refractive index ≥ 1.60, ●: 1.55 ≤ refractive index < 1.60, ▲: 1.50 ≤ refractive index < 1.55, X: < 1.50.

[0220] (2) Transmission rate evaluation

[0221] After spin-coating a negative photoresist composition onto a glass substrate, the coated surface was pre-dried by heating (at 100°C for 90 seconds). Without exposure through a photomask, it was developed in a tetramethylammonium hydroxide (TMAH) aqueous solution at 25°C for 60 seconds, rinsed with pure water for 1 minute, and then heated in an oven at 230°C for 30 minutes to form a cured product. The cured product was then placed in an oven at 150°C for 240 hours of thermal aging, and the transmittance of the cured product was measured using a UV-Vis spectrophotometer at a wavelength of 400 nm.

[0222] Evaluation criteria: ◎: Excellent, ●: Good, ▲: Average, X: Poor. Based on transmittance data, the evaluation is as follows: ◎: >95%, ●: 90% ≤ transmittance ≤ 95%, ▲: 85% ≤ transmittance < 90%, X: < 85%.

[0223] (3) Hardness evaluation

[0224] The curing process of the cured product is the same as that of the transmittance test. The hardness of the cured product is tested using a pencil hardness tester. A standard pencil (Mitsubishi pencil: 1~6H, HB, 1~6B) is used to scratch the product under a 750g load. The hardness is represented by the pencil without scratch marks. Hardness evaluation criteria: hardness increases sequentially from 6B, 5B, 4B, 3B, 2B, B, HB, H, 2H, 3H, 4H, 5H, 6H.

[0225] Evaluation criteria: ◎: Excellent, ●: Good, ▲: Medium, X: Poor. Based on hardness data, the evaluation is as follows: ◎: ≥3H, ●: 2H, ▲: H, X: ≤HB.

[0226] (4) Evaluation of substrate adhesion

[0227] The curing process of the cured product is the same as that of the transmittance test. The adhesion between the cured product and the substrate is tested using a cross-cut test. Using the ATSM-D3359 method, 100 checkerboard markings are formed on the cured product using a corner cutter via a checkerboard tape method. Then, 3M Scotch 600 tape is used for peeling. The number of peeled checkerboard markings that detach from the 100 peeled markings is measured. The percentage of peeled checkerboard markings is evaluated as follows: 5B: No peeling (0%), 4B: Peeling less than 5%, 3B: Peeling 5%-15% (excluding 15%), 2B: Peeling 15%-35% (excluding 35%), 1B: Peeling 35%-65%, 0B: Peeling > 65%.

[0228] Evaluation criteria: ◎: Excellent (5B), ●: Good (4B), ▲: Average (3B), X: Poor (<3B).

[0229] (5) Evaluation of radioactivity

[0230] After preparing a negative photoresist composition by spin coating or slot coating on a transparent substrate, the coated surface is pre-dried by heating (pre-drying at 100°C for 90 seconds), and then exposed through a photomask with a pattern of 1-50 μm. After exposure, it is developed in an aqueous solution of tetramethylamine hydroxide (TMAH) (2.38% by mass) at 25°C for 60 seconds, rinsed with pure water for 1 minute, and heated in an oven at 230°C for 30 minutes to form a pattern.

[0231] Evaluation criteria: ◎: Excellent, ●: Good, ▲: Average, X: Poor. Based on pattern size, the evaluation is as follows: ◎: 1-5um, ●: 6-15um, ▲: 16-50um, X: >50um, cannot be developed.

[0232] (6) Weight-average molecular weight test: The weight-average molecular weight of the acrylic copolymer resins in the examples and comparative examples was tested using an Agilent liquid chromatography system (1260 Infinity II, Agilent Technologies, USA). 0.1 g of acrylic copolymer resin was placed in a 40 mL sample bottle, 4 g of tetrahydrofuran (THF) was added, and the mixture was shaken to dissolve for 1 min to obtain the sample. The sample was tested at a flow rate of 1 mL / min.

[0233] Table 1

[0234]

[0235]

[0236] Table 2

[0237]

[0238] As shown in Table 2, compared with Comparative Examples 1 to 10, the negative photoresist compositions in Examples 1 to 22 include a first initiator, an acrylic monomer, and an acrylic copolymer resin containing a first structural unit shown in Formula 1, a second structural unit shown in Formula 2, and a third structural unit shown in Formula 3. The negative photoresist compositions have good anti-aging properties (i.e., their cured products still maintain high transmittance after being heat-aged at 150 °C for 240 hours), and also have high refractive index, high transmittance, high adhesion, and high hardness.

[0239] Specifically, compared to Comparative Examples 7-9, the negative photoresist composition in Example 1 includes a first initiator, an acrylic monomer, and an acrylic copolymer resin containing a first structural unit shown in Formula 1, a second structural unit shown in Formula 2, and a third structural unit shown in Formula 3. This negative photoresist composition has good anti-aging properties (i.e., its cured product still maintains high transmittance after being heat-aged at 150 °C for 240 hours), and also has high refractive index, high transmittance, high adhesion, and high hardness.

[0240] Compared to Comparative Examples 1-6, the acrylic copolymer resin in the negative photoresist compositions of Examples 1-6 contains a first structural unit, which improves the anti-aging properties, refractive index, hardness, and adhesion of the negative photoresist compositions. For example, compared to Comparative Example 1, Example 1 uses the first acrylate monomer shown in Formula 10-1 to form the first structural unit, which improves the anti-aging properties, refractive index, hardness, and adhesion of the negative photoresist composition.

[0241] Compared to Example 20, Examples 1 and 19 further control 0 < a ≤ 3, where a is the mass ratio of acrylic monomer to acrylic copolymer resin, further improving the refractive index and hardness of the negative photoresist composition.

[0242] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A negative photoresist composition, characterized by comprising: The negative photoresist composition is composed of an acrylic copolymer resin, an acrylic monomer, a first initiator, an additive, and a solvent; the acrylic copolymer resin comprises a first structural unit, a second structural unit, and a third structural unit; the first structural unit is as shown in Formula 1: Formula 1, wherein R1 is selected from any one of a hydrogen atom and a methyl group, R2 and R3 are each independently selected from any one of a group as shown in Formula 1-1 and Formula 1-2, and n1 is any integer from 1 to 10, Formula 1-1, Formula 1-2; the second structural unit is as shown in Formula 2: Formula 2, wherein R1 is selected from any one of a hydrogen atom and a methyl group, R2 is selected from any one of a group as shown in Formula 1-1 and Formula 1-2, R4 is selected from any one of a carboxyl group and a hydroxyl group, and n2 is any integer from 1 to 10, Formula 1-1, Formula 1-2; the third structural unit is as shown in Formula 3: Formula 3; wherein R1 is selected from any one of a hydrogen atom and a methyl group, R2 is selected from any one of a group as shown in Formula 1-1 and Formula 1-2, R5 is selected from any one of a group as shown in Formula 3-1, Formula 3-2, and Formula 3-3, and n3 is any integer from 1 to 10, Formula 1-1, Formula 1-2, Formula 3-1, Formula 3-2, Formula 3-3.

2. The negative photoresist composition according to claim 1, wherein the first structural unit comprises one or more of structural units as shown in Formula 4-1, Formula 4-2, and Formula 4-3: Formula 4-1, Formula 4-2, Equation 4-3; and / or, the second structural unit comprises one or more of structural units as shown in Formula 5-1, Formula 5-2, and Formula 5-3: Formula 5-1, Formula 5-2, Equation 5-3; and / or, the third structural unit comprises one or more of structural units as shown in Formula 6-1, Formula 6-2, and Formula 6-3: Formula 6-1, Formula 6-2, Equation 6-3; and / or, the acrylic copolymer resin has a weight average molecular weight of 500 g / mol to 100000 g / mol; and / or, the acrylic copolymer resin accounts for 5% to 95% of the negative photoresist composition in terms of mass percentage.

3. The negative photoresist composition according to claim 1, wherein The acrylic copolymer resin is co-polymerized from monomer raw materials comprising a first acrylic ester monomer, a second acrylic ester monomer, and a third acrylic ester monomer; Preferably, the first acrylic ester monomer has a structure as shown in Formula 7: Formula 7, wherein R1 is selected from any one of a hydrogen atom and a methyl group, R2 and R3 are each independently selected from any one of a group as shown in Formula 1-1 and Formula 1-2, and n1 is any integer from 1 to 10, Formula 1-1, Formula 1-2; Preferably, the second acrylic ester monomer has a structure as shown in Formula 8: Formula 8, wherein R1 is selected from any one of a hydrogen atom and a methyl group, R2 is selected from any one of a group as shown in Formula 1-1 and Formula 1-2, R4 is selected from any one of a carboxyl group and a hydroxyl group, and n2 is any integer from 1 to 10, Formula 1-1, Formula 1-2; Preferably, the third acrylic ester monomer has a structure as shown in Formula 9: Formula 9, wherein R1 is selected from any one of a hydrogen atom and a methyl group, R2 is selected from any one of a group as shown in Formula 1-1 and Formula 1-2, R5 is selected from any one of a group as shown in Formula 3-1, Formula 3-2, and Formula 3-3, and n3 is any integer from 1 to 10, Formula 1-1, Formula 1-2, Formula 3-1, Formula 3-2, Formula 3-3; Preferably, the first acrylic ester monomer accounts for 5% to 95% of the monomer raw materials in terms of mass percentage; Preferably, the second acrylic ester monomer accounts for 5% to 95% of the monomer raw materials in terms of mass percentage; Preferably, the third acrylate monomer accounts for 5% to 95% of the mass percentage of the monomer raw material.

4. The negative photoresist composition according to claim 3, wherein The first acrylate monomer includes one or more of compounds represented by Formula 10-1, Formula 10-2, Formula 10-3: Formula 10-1, Formula 10-2, Equation 10-3; and / or, the second acrylate monomer includes one or more of compounds represented by Formula 11-1, Formula 11-2, Formula 11-3: Formula 11-1, Formula 11-2, Equation 11-3; and / or, the third acrylate monomer includes one or more of compounds represented by Formula 12-1, Formula 12-2, Formula 12-3: Formula 12-1, Formula 12-2, Equation 12-3.

5. The negative photoresist composition according to claim 1, wherein The acrylic monomer includes a (meth)acrylate monomer containing at least two C=C groups; and / or, the negative photoresist composition satisfies: 0 and / or, the first initiator includes one or more of a photoinitiator, a thermal initiator, a thermal acid generator; and / or, the negative photoresist composition satisfies: 0 and / or, the negative photoresist composition further includes one or more of an additive, a solvent, the additive including one or more of a silane coupling agent, a leveling agent; Preferably, the mass ratio of the additive to the acrylic copolymer resin is 0.001 to 0.1; Preferably, the solvent includes propylene glycol monomethyl ether acetate.

6. The negative photoresist composition according to claim 5, wherein The negative photoresist composition satisfies: 0.5 7. The negative photoresist composition according to claim 5, wherein The negative photoresist composition satisfies: 0.8 8. The negative photoresist composition according to claim 5, wherein The negative photoresist composition satisfies: 0.01 9. The negative photoresist composition according to claim 5, wherein The (meth)acrylate monomer containing at least two C=C groups includes one or more of a (meth)acrylate monomer containing two C=C groups, a (meth)acrylate monomer containing three C=C groups, and a (meth)acrylate monomer containing more than three C=C groups; and / or, the photoinitiator includes one or more of an O-acyloxime compound, an acyloin compound, an acyloin ether compound, a phenylethanone compound, a benzophenone compound, a quinone compound, a halogen compound, and an acyloxyphosphine compound; and / or, the thermal initiator includes one or more of a peroxide and an azo compound; and / or, the thermal acid generator includes a sulfonium salt.

10. A method for producing the negative photoresist composition according to any one of claims 1 to 9, characterized by, The method includes the following steps: mixing the first initiator, the acrylic monomer, and the acrylic copolymer resin to obtain the negative photoresist composition; Preferably, the process of mixing the first initiator, the acrylic monomer, and the acrylic copolymer resin includes: after mixing the first initiator, the additive, the acrylic monomer, and the acrylic copolymer resin, adding a solvent thereto to obtain the negative photoresist composition.

11. A structural member, characterized by A cured product obtained by curing the negative photoresist composition of any one of claims 1 to 9 or the negative photoresist composition prepared according to the method of claim 10.

12. The structural member of claim 11, wherein, The refractive index of the cured product is 1.55 to 1.65; And / or, the transmittance of the cured product after heat aging at 150±5 ℃ for 240±2 hours is greater than or equal to 95%.

13. A method of producing a structural member as claimed in any one of claims 10 to 11, characterised in that, The method comprises the following steps: The negative photoresist composition is subjected to a molding process to obtain a molded product; The molded product is subjected to exposure and then developed with a developer to obtain the structural member; wherein the developer comprises an alkaline solution.

Images