Black spacer photosensitive composition and black spacer

Abstract

The application discloses a black interval photosensitive composition and a black spacer. The black interval photosensitive composition comprises an alkali-soluble resin, a photopolymerizable monomer, a photoinitiator, a solvent, an opacifier, a thixotropic agent and a dispersing agent; the alkali-soluble resin is a resin composition mixed by an acrylic copolymer and a fluorenyl-containing acrylic copolymer; the photopolymerizable monomer is at least one acrylic ester containing an olefinic unsaturated bond, including a monofunctional acrylic ester, a bifunctional acrylic ester and a multifunctional acrylic ester. The black interval photosensitive composition of the application regulates the leveling property of the photosensitive composition by selecting the alkali-soluble resin with a specific molecular weight, the photopolymerizable monomer with a high functionality and adding the inorganic nanoparticles as the thixotropic agent, realizes the high light shielding while still controlling the height difference of the spacer, and reduces the curing requirement and the cost.

Description

Technical Field

[0001] This invention relates to the field of liquid crystal displays, and more particularly to a black spacer photosensitive composition and a black spacer for use in liquid crystal display panels. Background Technology

[0002] In display devices such as liquid crystal displays (LCDs), black spacers are key components that combine gap control and light-shielding functions. As an emerging material proposed in recent years to replace the traditional two-step process of transparent spacers (photo spacers) and black matrices, it reduces manufacturing processes and costs, and is also suitable for high-resolution, narrow-bezel, and curved LCD products. To make the spacers light-shielding, light-shielding materials such as carbon black or other highly light-shielding inorganic materials are often added. However, with the addition of these light-shielding materials, on the one hand, they absorb some of the ultraviolet light that promotes the photocuring reaction, resulting in reduced curability of the spacers. Under conditions of using masks with different transmittance, it is difficult to control the height difference and shape of the spacers. Furthermore, the poor insulation (such as carbon black) or poor dispersibility of the light-shielding materials themselves also have an adverse effect on the voltage retention rate and pattern yield of the liquid crystal.

[0003] Currently, the main approach to resolving the contradiction between high light-blocking properties and good curability in visible light applications is to select organic black pigments that match the transmittance of specific wavelengths. Furthermore, most organic black pigments also exhibit excellent insulation properties. Patent TW202342567A proposes an innovative dispersion for black spacer materials. This dispersion involves surface-coating carbon black, used as a colorant, with an insulating material and incorporating micronized lactam organic black to reduce reflectivity. This solves the problems of small cone angles and high reflectivity in existing black spacer materials, while maintaining high electrical insulation and light-blocking properties, thus contributing to improved display device performance and image quality.

[0004] Patent CN111190328A discloses a high-performance photosensitive coloring composition comprising a specific organic black pigment, a quaternary ammonium salt-based polymeric dispersant, an alkali-soluble resin, a photopolymerization initiator, and optional auxiliary components. It points out that traditional organic opacifiers suffer from poor dispersion and utilizes a combination of organic pigments with a specific structure and a dedicated dispersant to achieve high opacity, dispersion stability, and photolithographic performance through synergistic component action.

[0005] Although organic pigments have better dispersibility and insulation than inorganic pigments, and exhibit better curability, their light-blocking ability is relatively insufficient. Furthermore, most organic black pigments exhibit color variations, and light leakage may occur in certain visible light wavelengths. Therefore, to improve light-blocking ability, it is often necessary to increase the film thickness to prevent light leakage, which negatively impacts both cost and manufacturing process. Summary of the Invention

[0006] To address the aforementioned problems, this invention aims to provide a black spacer photosensitive composition and a black spacer prepared therefrom that can be used in liquid crystal displays, organic EL displays, and the like. By controlling the leveling properties of this black spacer photosensitive composition, its poor leveling properties prevent the collapse of the shallow cross-linked regions in the partially transmittant areas during exposure and subsequent baking, thereby stabilizing the height difference of the spacer. The restricted heat flow in the shallow cross-linked regions means reduced exposure cross-linking requirements and curing requirements, allowing for a further increase in the proportion of added organic black pigment, better light-blocking properties per unit film thickness, and reduced requirements for photomasks, resulting in a significant cost reduction.

[0007] The inventors have discovered that, in order to control the leveling properties of the black spacer photosensitive composition, the alkali-soluble resin in this invention contains a relatively high molecular weight acrylic resin and a fluorene-containing acrylic resin; and a multifunctional photopolymerizable monomer is selected to increase the crosslinking density and increase the rigidity of the material; and a certain amount of inorganic nanoparticles are added as a thixotropic agent to further adjust its leveling properties, thereby obtaining a black spacer photosensitive composition that can achieve a height difference between black spacers.

[0008] The present invention provides a black spaced photosensitive composition comprising: (A) an alkali-soluble resin, (B) a photopolymerizable monomer, (C) a photoinitiator, (D) a solvent, (E) a light-blocking agent, (F) a thixotropic agent, and (G) a dispersant; The alkali-soluble resin refers to a resin composition made by mixing (A1) acrylic copolymer and (A2) fluorene-containing acrylic copolymer.

[0009] Preferably, the (A1) acrylic copolymer is copolymerized from a first unsaturated monomer containing at least one carboxyl group and a second unsaturated monomer. The first unsaturated monomer containing at least one carboxyl group is preferably acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid, citraconic acid, or a combination thereof. The second unsaturated monomer is preferably an olefinic unsaturated compound with an aromatic ring (e.g., styrene, α-methylstyrene, vinyltoluene, vinyl benzyl methyl ether, etc.) or an unsaturated carboxylic acid ester compound (e.g., methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-hydroxyethyl methacrylate). The compounds include one or more of the following: esters, 2-hydroxybutyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, etc.; unsaturated aminoalkyl carboxylic acid esters (e.g., 2-aminoethyl methacrylate, 2-dimethylaminoethyl methacrylate, etc.); vinyl carboxylic acid esters (e.g., vinyl acetate, vinyl benzoate, etc.); unsaturated glycidyl carboxylic acid esters (e.g., glycidyl methacrylate, etc.); vinyl cyanide compounds (e.g., methacrylonitrile, etc.); and unsaturated amide compounds (e.g., methacrylamide, etc.).

[0010] The (A1) acrylic copolymer can be prepared by mixing two polymeric monomers (a first unsaturated monomer and a second unsaturated monomer), adding a molecular weight control agent, a polymerization initiator, and a solvent, then filling the mixture with nitrogen and slowly stirring the mixture for polymerization.

[0011] There are no particular restrictions on molecular weight control agents, such as n-dodecyl mercaptan, tert-dodecyl mercaptan, and mercaptoacetate esters.

[0012] There are no particular restrictions on polymerization initiators, such as azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, and di-tert-butyl peroxide. They can be used alone or in combination of two or more.

[0013] The weight-average molecular weight of the (A1) acrylic copolymer synthesized in this invention can be distributed in the range of 4,000 to 150,000 g / mol, preferably in the range of 10,000 to 100,000 g / mol.

[0014] The fluorenyl acrylic copolymer (A2) described in this invention mainly relies on the rigid structure of its fluorenyl functional groups, which can provide good rigidity and wear resistance for the film-forming body. It can be directly purchased from Qiangli New Materials products and can be selected from one or two of the following products for use in combination: TR-B20101 and TR-B20102.

[0015] The preferred ratio of the (A1) acrylic copolymer to the (A2) fluorene-containing acrylic copolymer is 15:75 to 75:15.

[0016] In this invention, the alkali-soluble resin accounts for 10% to 70% of the mass of the black spacer photosensitive composition, and more preferably 15% to 60%.

[0017] In this invention, the photopolymerizable monomer (B) generally refers to a compound that can be polymerized by a photoinitiator. The photopolymerizable monomer of this invention refers to an acrylate containing at least one olefinic unsaturated bond, including monofunctional acrylates, difunctional acrylates, and polyfunctional acrylates.

[0018] The monofunctional acrylates include methyl methacrylate, hydroxyethyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, hydroxypropyl methacrylate, etc.

[0019] The aforementioned bifunctional acrylates include 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, 1,4-butanediol diacrylate, cyclohexanediol diacrylate, polyethylene glycol diacrylate, ethylene glycol dimethacrylate, etc.

[0020] The multifunctional acrylates include trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, bis(trimethylolpropane tetraacrylate), dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tri(2-hydroxyethyl)isocyanurate triacrylate, ethoxylated glycerol triacrylate, propoxylated glycerol triacrylate, ethoxylated pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexamethacrylate, etc.

[0021] Based on adjusting the crosslinking density, this invention preferably uses a combination of monofunctional methyl methacrylate esters, as well as pentaerythritol pentaacrylate, pentaerythritol hexaacrylate, and other acrylates with five or more functions, and the proportion of polyfunctional acrylates is preferably between 50-70%. The photopolymerizable monomer of this invention is more preferably a mixture of benzyl methacrylate (B1) and pentaerythritol hexaacrylate (B2). The photopolymerizable monomers described in this invention preferably account for 10% to 40% of the mass of the black spacer photosensitive composition, and more preferably 15% to 30%.

[0022] In this invention, the photoinitiator (C) refers to the core photosensitive component that rapidly generates active free radicals after absorbing ultraviolet light, thereby triggering the cross-linking and curing of photopolymerizable monomers and alkali-soluble resins. It directly determines the curing speed, pattern clarity, and film performance. The photoinitiator of this invention may include acetophenone compounds, benzophenone compounds, thioxanone compounds, benzoin compounds, triazine compounds, oxime ester compounds, etc. Oxime ester compounds are preferred in this invention. The oxime ester compounds are preferably one or more of the following: 1-(4-phenylthiophenyl)-1,2-octanedione-2-oxobenzoyl oxime, 1-(9-ethyl-6-2-methylbenzoyl-9H-carbazole-3-yl) ethyl ketone-1-oxoacetyl oxime, 2-(benzoyloxyoxime)-1-[4-(phenylthio)phenyl]-1-butanone, 1-(9-ethyl-6-benzoyl-9H-carbazole-3-yl) ethyl ketone-1-oxoacetyl oxime, 1-[4-(4-benzoylphenylthio)phenyl]-1,2-octanedione-2-oxobenzoyl oxime, and 2-acetoxyimino-1-(4-phenylthiophenyl)-1-octanone.

[0023] In this invention, the solvent (D) is not particularly limited, as long as it can dissolve the above components and is chemically stable. For example, the solvent may be an alcohol, ether, glycol ether, ethylene glycol alkyl ether acetate, diethylene glycol, propylene glycol monoalkyl ether, propylene glycol alkyl ether acetate, propylene glycol alkyl ether propionate, aromatic hydrocarbon, ketone, ester, etc.

[0024] Specific examples of solvents include methanol, ethanol, tetrahydrofuran, dioxane, methyl cellosolve acetate, ethyl cellosolve acetate, ethyl acetoacetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, dipropylene glycol dimethyl ether, and so on. Propylene glycol diethyl ether, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol butyl ether acetate, toluene, xylene, methyl ethyl ketone, 4-hydroxy-4-methyl-2-pentanone, cyclopentanone, cyclohexanone, 2-heptanone, γ-butyrolactone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc.

[0025] In this invention, the solvents are preferably ethylene glycol alkyl ether acetates, diethylene glycol, propylene glycol monoalkyl ethers, propylene glycol alkyl ether acetates, ketones, etc. More specifically, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol methyl ether acetate, methyl 2-methoxypropionate, etc. The solvents exemplified above can be used alone or in combination of two or more thereof.

[0026] The amount of solvent in the black spacer photosensitive composition of the present invention is not particularly limited. For example, the total weight of the solvent can be used, with a solid content of 10 to 70% by weight, preferably 15 to 60% by weight.

[0027] If the amount of solvent is within the range mentioned above, the composition can be easily coated and its flowability can be maintained at an appropriate level.

[0028] In this invention, the (E) opacifier is preferably a black organic pigment, such as aniline black (acrazine derivative), perylene black, phthalocyanine black and metallic phthalocyanine black, etc. This invention prefers perylene black materials, and can choose to use Pigment Black 31 and Pigment Black 32, which are commercially available products manufactured by BASF under the brand name L0086, and more preferably Pigment Black 32.

[0029] In this invention, the (F) thixotropic agent refers to a thixotropic agent with a non-strong thixotropic effect, which, without affecting the coating, has a certain inhibitory effect on the thermal flow during post-baking, ensuring that the black spacer pattern does not collapse or deform. The thixotropic agent described in this invention can be commercially available fumed silica nanoparticles. The thixotropic agent involved in this invention was purchased from Evonik AEROSILR972. Due to dispersion considerations, the thixotropic agent and the opacifier in this invention require a dispersion process.

[0030] In this invention, the (G) dispersant can be any dispersant commonly used in the art, and the dispersant of this invention is preferably BYK-163 type dispersant from BYK Chemicals.

[0031] In preparing the black spacer photosensitive composition of the present invention, the corresponding mass of black organic pigment and solvent are generally weighed, and an appropriate amount of dispersant is added. After dispersion, a light-blocking agent dispersion is obtained, the solid content of which is preferably between 10-30%. If necessary, a small amount of polymeric leveling agent may also be added during the preparation of the composition of the present invention.

[0032] The present invention also provides a method for forming black spacers using the above-described black spacer photosensitive composition. The black spacers can be formed by methods known in the art, for example, by coating the black spacer photosensitive composition onto a substrate and then photocuring it under a halftone mask.

[0033] More specifically, in the curing step, the black spacer photosensitive composition coated on the substrate can be pre-baked at a temperature of, for example, 80°C to 120°C to remove the solvent; then exposed using a halftone mask with the desired pattern to control the formation of primary and secondary spacer pillars with varying heights; and developed using a developer (potassium hydroxide solution) to form a pattern on the coating. Subsequently, if desired, the patterned coating is post-baked at a temperature of 180°C to 250°C for 10 minutes to 2 hours to prepare the desired black spacers. Exposure can be performed in the 200 to 500 nm wavelength range, with a wavelength of 365 nm as a reference, at an exposure rate of 10 to 100 mJ / cm². According to the method of the invention, from a process point of view, the desired pattern can be easily formed.

[0034] The beneficial effects of the present invention are as follows: The black spacer photosensitive composition of the present invention controls the leveling properties of the photosensitive composition by selecting alkali-soluble resins of specific molecular weights, high-functionality photopolymerizable monomers, and adding inorganic nanoparticles as thixotropic agents. This achieves high light-blocking while still controlling the height difference of the spacers, and reduces the curing requirements, resulting in lower costs. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the leveling of the boss. As shown in the figure, the height difference requirement of the main and auxiliary spacers can be ensured by adjusting the leveling properties of the material.

[0036] Figure 2 The images show the leveling effect of the cured film, where (a) is Example 1, (b) is Example 2, (c) is Comparative Example 1, (d) is Comparative Example 2, (e) is Comparative Example 3, and (f) is Comparative Example 4.

[0037] Figure 3 The images show the exposure linewidths, where (a) is Example 1, (b) is Example 2, (c) is Comparative Example 1, (d) is Comparative Example 2, and (e) is Comparative Example 4. Detailed Implementation

[0038] The “range” disclosed in this document takes the form of a lower limit and an upper limit. It can be one or more lower limits and one or more upper limits, respectively. A given range is defined by selecting a lower limit and an upper limit. The selected lower and upper limits define the boundaries of the particular range. All ranges that can be defined in this way are inclusive and composable; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is also expected that ranges of 60-110 and 80-120 are also included. Furthermore, if the minimum range values ​​are listed as 1 and 2, and if the maximum range values ​​are listed as 3, 4, and 5, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5.

[0039] In this application, unless otherwise stated, the numerical range "ab" is a shortened representation of any combination of real numbers from a to b, where a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" have been listed in this document, and "0-5" is simply a shortened representation of these numerical combinations.

[0040] Unless otherwise specified in this application, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions.

[0041] Unless otherwise specified, all technical features and preferred features mentioned herein can be combined to form new technical solutions.

[0042] In this application, unless otherwise specified, the term "comprising" as used herein can be either open-ended or closed-ended. For example, "comprising" may mean that it may also include other components not listed, or it may only include the listed components.

[0043] The weight-average molecular weight of each component described below was measured by gel permeation chromatography (GPC, eluent: tetrahydrofuran) using polystyrene standards.

[0044] Synthesis Example 1: Synthesis of Acrylic Acid Copolymer (A1) 600 parts by weight of propylene glycol methyl ether acetate were added as a solvent to a 5L four-necked round-bottom flask equipped with a reflux condenser, a constant-pressure dropping funnel, a thermometer, and a mechanical stirrer. The solvent temperature was raised to 75°C, and the solvent was slowly stirred at 250 rpm. Next, 420 parts by weight of methyl methacrylate and 180 parts by weight of ethyl acrylate were added. After purging with nitrogen for 30 minutes to remove oxygen, 2.83 parts by weight of azobisisobutyronitrile (AIBN) were added for prepolymerization for 30 minutes. Subsequently, over 3 hours, a mixed monomer solution consisting of 150 parts by weight of acrylic acid, 50 parts by weight of hydroxyethyl acrylate, the remaining propylene glycol methyl ether acetate, and the remaining AIBN was added dropwise. Simultaneously, 4.2 parts by weight of dodecanethiol was added dropwise in three batches at 1-hour intervals as a molecular weight regulator. The reaction temperature was maintained at 78–80°C, and the stirring speed was maintained at 300 rpm to carry out the polymerization reaction. After the addition was complete, the reaction temperature was raised to 82°C, and 0.5 parts by weight of azobisisobutyronitrile was added and kept at the temperature for 2 hours. Then the temperature was lowered to below 40°C, and impurities were removed by filtration. A product with a solid content of 45±2% by weight was obtained. Therefore, an acrylic copolymer A1 with a weight average molecular weight of about 38,000 to 42,000 Da was synthesized.

[0045] Synthesis Example 2: Synthesis of a light-blocking agent (E1) containing a small amount of thixotropic agent. Add 406.4 parts by weight of propylene glycol methyl ether acetate as a solvent to a reactor equipped with a mechanical stirrer, reflux condenser, and constant-temperature oil bath. Turn on the stirrer and adjust the speed to 400 rpm, stabilizing the solvent temperature at 25±2℃ to ensure uniform stirring, laying a good foundation for the uniform dispersion of subsequent components. Then add 20 parts by weight of BYK-163 polyurethane dispersant and stir for 10 minutes until the dispersant is completely dissolved, forming a uniform and transparent dispersion system. Slowly add 80 parts by weight of Pigment Black 32 to the above dispersion system. Control the feeding rate at 5 parts by weight / 5 minutes to avoid rapid pigment aggregation and the formation of difficult-to-disperse agglomerates. After the feeding is complete, increase the stirring speed to 1000 rpm and maintain a constant temperature of 25℃ for 30 minutes to complete the initial pre-dispersion of the pigment. Next, 1.2 parts by weight of AEROSIL R972 hydrophobic nano-silica was added as a thixotropic agent, and stirring was continued for 20 minutes to achieve initial dispersion. The system was then transferred to a sand mill, and the speed was adjusted to 1900 rpm for 2 hours of grinding. During this time, samples were taken every 30 minutes to check the particle size until the system particle size reached D50 < 80 nm and D90 < 120 nm, ensuring uniform dispersion. The ground system was then returned to the reactor, and the stirring speed was adjusted to 450 rpm. 0.4 parts by weight of a high-molecular-weight acrylate leveling agent was slowly added, and stirring was continued for 30 minutes to eliminate micro-bubbles and optimize coating performance. The system was then filtered through a 2 μm filter membrane to remove any small, incompletely dispersed impurities, yielding a light-blocking agent E1 containing a small amount of thixotropic agent for use in black spacer photosensitive compositions.

[0046] Synthesis Example 3: Synthesis of a light-blocking agent (E2) without thixotropic agents The same method as in Synthesis Example 2 was used, but without adding a thixotropic agent, and the mixture was directly transferred to a sand mill to obtain a thixotropic-free opaque agent E2 for use in the black spacer photosensitive composition.

[0047] The black spaced photosensitive compositions of the following examples and comparative examples were prepared using the compounds prepared in the above synthesis examples.

[0048] Table 1 List of components used in the examples and comparative examples

[0049] Example 1 7.5 parts by weight of the acrylic copolymer (A1) of Synthesis Example 1, 4.8 parts by weight of the fluorene-containing acrylic resin (A2) TR-B20101, 1.5 parts by weight of 2-(benzoyloxyoxime)-1-[4-(phenylthio)phenyl]-1-butanone (C), 10.4 parts by weight of dipentaerythritol hexaacrylate B2, 2.8 parts by weight of benzyl methacrylate B1, and 20 parts by weight of the opacifier (E1) of Synthesis Example 2 were uniformly mixed. The mixture was dissolved in propylene glycol methyl ether acetate to a solids content of 20% by weight. The solution was stirred for 2 hours and filtered successively through membrane filters with pore sizes of 2 μm and 0.5 μm to obtain a composition solution with a solids content of 20% by weight.

[0050] Example 2 and Comparative Examples 1-4 The black spacer photosensitive compositions were each prepared in the same manner as in Example 1, except that the types and / or contents of the alkali-soluble resin, polymerizable monomer, and opacifier varied as shown in Table 2 below, where all units are parts by mass in Example 1.

[0051] Table 2 List of components used in each embodiment

[0052] Test Example 1: Evaluating Leveling Properties The compositions prepared in the examples and comparative examples were each spin-coated onto a glass substrate with pre-fabricated approximately 1-micron bosses. The coated substrates were then pre-baked on a hot plate maintained at 100°C for 100 seconds to form a dried film. Exposure was then performed under a halftone photomask with a 28-μm linear aperture pattern at an energy of 30 mw / cm². 2 Exposure was performed. The dried film was developed at 23°C using a developer (a 0.043% KOH aqueous solution) to create the pattern. The resulting exposed film was then heated in a convection oven at 230°C for 30 minutes to prepare a cured film with a thickness of 2.5 μm. The thickness of each part of the cured film, which had formed the primary and secondary black spacer pattern, was measured using a scanning electron microscope, as shown in the attached figure. The following criteria were used to determine whether its leveling properties met the target requirements.

[0053] Judgment criteria: H3 / (H1+H2)≥90% is excellent, and H3 / (H1+H2)<90% is unqualified.

[0054] Test Example 2: Evaluating developability and exposure sensitivity The resin compositions prepared in the examples and comparative examples were each spin-coated onto glass substrates. The coated substrates were then pre-baked on a hot plate maintained at 100°C for 100 seconds to form a dried film. Exposure, development, and post-baking were performed in the same manner as in Test Example 1. The pattern on the cured film was observed using a metallographic microscope. If there was residual development or no development, it was considered poor development; if there was no residual development, it was considered excellent development. Linewidths smaller than the corresponding photomask linewidth (10 μm) were considered unacceptable, while linewidths larger than the corresponding photomask linewidth were considered acceptable.

[0055] Table 3 shows the comparison results of key performance tests.

[0056] Table 3 Performance test results of each embodiment

[0057] As shown in Table 3 above, the compositions of the embodiments within the scope of this invention are generally excellent in all key properties. Conversely, the compositions of the comparative embodiments not within the scope of this invention show that at least one of these properties is disadvantageous.

Claims

1. A black-spaced photosensitive composition, characterized in that, include: (A) Alkali-soluble resin, (B) Photopolymerizable monomer, (C) Photoinitiator, (D) Solvent, (E) Opacifier, (F) Thixotropic agent, and (G) Dispersant; The alkali-soluble resin refers to a resin composition formed by mixing (A1) acrylic copolymer and (A2) fluorene-containing acrylic copolymer; the mass ratio of (A1) acrylic copolymer to (A2) fluorene-containing acrylic copolymer is 15:75~75:15; The photopolymerizable monomer (B) contains at least one olefin unsaturated bond in the acrylate, including monofunctional acrylates, difunctional acrylates, and polyfunctional acrylates; wherein the proportion of difunctional acrylates and polyfunctional acrylates in the photopolymerizable monomer is between 50% and 70%. The (E) opaque agent is a black organic pigment.

2. The black spaced photosensitive composition as described in claim 1, characterized in that, The (A1) acrylic copolymer is copolymerized from a first unsaturated monomer containing at least one carboxyl group and a second unsaturated monomer. The first unsaturated monomer containing at least one carboxyl group is preferably acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid, citraconic acid, or a combination thereof. The second unsaturated monomer is preferably an olefinic unsaturated compound with an aromatic ring (preferably styrene, α-methylstyrene, vinyltoluene, vinyl benzyl methyl ether, etc.), or an unsaturated carboxylic acid ester compound (preferably methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, etc.). The compounds include one or more of the following: 2-hydroxybutyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, etc.; unsaturated aminoalkyl carboxylic acid ester compounds (preferably 2-aminoethyl methacrylate, 2-dimethylaminoethyl methacrylate, etc.); vinyl carboxylic acid ester compounds (preferably vinyl acetate, vinyl benzoate, etc.); unsaturated glycidyl carboxylic acid ester compounds (preferably glycidyl methacrylate, etc.); vinyl cyanide compounds (preferably methacrylonitrile, etc.); and unsaturated amide compounds (preferably methacrylamide, etc.).

3. The black spaced photosensitive composition as described in claim 1, characterized in that, The weight-average molecular weight distribution of the (A1) acrylic copolymer is in the range of 4,000 to 150,000 g / mol, preferably in the range of 10,000 to 100,000 g / mol.

4. The black spaced photosensitive composition as described in claim 1, characterized in that, The (A2) fluorene-containing acrylic copolymer is the TR-B20101 and TR-B20102 grade products of Qiangli New Materials.

5. The black spaced photosensitive composition as described in claim 1, characterized in that, The alkali-soluble resin accounts for 10% to 70% of the mass of the black spacer photosensitive composition, preferably 15% to 60%.

6. The black spaced photosensitive composition as claimed in claim 1, characterized in that, The monofunctional acrylates mentioned include methyl methacrylate, hydroxyethyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, hydroxypropyl methacrylate, etc. The aforementioned difunctional acrylates include 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, 1,4-butanediol diacrylate, cyclohexanediol diacrylate, polyethylene glycol diacrylate, ethylene glycol dimethacrylate, etc. The multifunctional acrylates include trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, bis(trimethylolpropane tetraacrylate), dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tri(2-hydroxyethyl)isocyanurate triacrylate, ethoxylated glycerol triacrylate, propoxylated glycerol triacrylate, ethoxylated pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexamethacrylate, etc. The photopolymerizable monomer (B) is more preferably a mixture of benzyl methacrylate (B1) and dipentaerythritol hexaacrylate (B2); The photopolymerizable monomer accounts for 10% to 40% of the mass of the black spacer photosensitive composition, and more preferably 15% to 30%.

7. The black spaced photosensitive composition as claimed in claim 1, characterized in that, The photoinitiator includes acetophenone compounds, benzophenone compounds, thioxanone compounds, benzoin compounds, triazine compounds, and oxime ester compounds, preferably oxime ester compounds.

8. The black spaced photosensitive composition as claimed in claim 1, characterized in that, The (F) thixotropic agent is fumed nano-silica.

9. A method for preparing a black spacer, characterized in that, This includes coating a substrate with the black spacer photosensitive composition as described in any one of claims 1 to 8, and then photocuring it under a halftone mask.

10. A black spacer obtained by the preparation method as described in claim 9.

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