Acrylate polyhedral oligomeric oxacalixarene compound, preparation method thereof, photoresist composition and application of acrylate polyhedral oligomeric oxacalixarene compound

Abstract

The invention belongs to the technical field of photoresist, and relates to an acrylate polyhedral oligomeric oxacalixarene compound, a preparation method thereof, a photoresist composition and application. The acrylate polyhedral oligomeric oxacalixarene compound is conjugated with carboxylic ester and acrylate groups, and fluorene-containing (methyl) acrylate resin (which has a huge fused ring structure, is high in molecular rigidity and can effectively limit oriented polarization of a dipole in an electric field) is further selected as film-forming resin; the low-dielectric photoresist composition with the dielectric constant being less than or equal to 2.6 is prepared by matching the low-dielectric photoresist with a photoinitiator, an auxiliary agent and a third organic solvent, and meanwhile, the core problems of insufficient graphical resolution, weak adhesive force on key substrates such as PSPI and the like and the like are solved, so that an ideal dielectric material is provided for a next-generation high-performance and large-size OLED touch display device.

Description

Acrylate cage-like oxacalixarene compounds, their preparation methods, photoresist compositions, and applications Technical Field

[0001] This invention belongs to the field of photoresist technology, and relates to an acrylate cage-like oxacalixarene compound, its preparation method, photoresist composition, and application. Background Technology

[0002] Organic light-emitting diodes (OLEDs), as devices that achieve electroluminescence using a multilayer organic thin-film structure, have become a key solution to meet the demands of new display technologies due to their significant advantages, including ease of fabrication, low driving voltage, high brightness, low power consumption, fast response speed, high luminous efficiency, wide viewing angle, and thinness and flexibility. In the complex structure of OLED devices, the capacitive touch devices integrated on the display panel place extremely stringent requirements on the dielectric properties of the materials. As display screen sizes continue to increase, the dielectric constant of the dielectric material used in touch devices must be sufficiently low to reduce parasitic capacitance, ensure sensitive and accurate touch signals, and thus improve the overall touch experience and performance.

[0003] Currently, silicon nitride (SiN) is commonly used in capacitive touch devices. x Inorganic materials such as silicon nitride are used as dielectric layers. However, silicon nitride has a relatively high dielectric constant (typically between 6 and 7), which can lead to a significant decrease in touch sensitivity, increased signal latency and noise in large-area display applications, severely impacting the performance of the final product and the user experience. To address this challenge, the industry is actively exploring the use of transparent photoresist materials with low dielectric constants to replace traditional inorganic dielectrics.

[0004] However, existing low-dielectric photoresist materials still face a series of unresolved key technical bottlenecks when applied to OLED touch devices: First, many low-dielectric materials have limited reductions in dielectric constant, making it difficult to meet the urgent demand for ultra-low dielectric constants (such as below 3.0) in large-size, high-precision touch applications; second, the materials have insufficient resolution performance, easily resulting in problems such as rough lines, unclear edge contours, or poor line width uniformity in micro-patterning processes, limiting their application in high-end, high-pixel-density display products; more importantly, the adhesion between existing low-dielectric photoresist materials and the pixel definition layer (such as polyimide-based PSPI materials) substrates commonly used in OLED devices is generally poor, easily leading to defects such as interface peeling and cracking during subsequent processes or use, seriously threatening the long-term reliability and yield of the devices.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide an acrylate cage-like oxacalixarene compound, its preparation method, photoresist composition, and application. This invention achieves its purpose through the following technical solution: Firstly, this invention provides an acrylate cage-like oxacalixarene compound, wherein the acrylate cage-like oxacalixarene compound has conjugated carboxylic acid ester and acrylate groups, and its specific structural formula is shown in formula (1) below: In formula (1), X is selected from acrylate groups containing phenyl groups that are substituted or unsubstituted by fluorine atoms, trifluoromethyl or fluorinated alkyl groups.

[0007] Specifically, X is any of the substituents shown in equations (2) to (5): .

[0008] On the other hand, the present invention provides a method for preparing the acrylate cage-like oxacalixarene compound as described above, comprising the following steps: Step 1, in a first organic solvent, a cage-like oxacalixarene compound having an acyl chloride group is mixed with an organic base to form a reaction mixture A; Step 2, after cooling the reaction mixture A to 0-10°C, a hydroxyl-containing (meth)acrylate compound is added to the reaction mixture A, and then an esterification reaction is carried out with the acyl chloride group, followed by heating to room temperature until the reaction is complete; Step 3, after the reaction is completed, the reaction is quenched with water, the product is extracted with a second organic solvent, and the crude product is obtained after drying and concentrating the organic phase; Step 4, the crude product is purified by column chromatography to obtain a cage-like oxacalixarene compound conjugated with carboxylic acid ester and acrylate groups.

[0009] Specifically, in step 1, the first organic solvent is selected from at least one of dichloromethane, tetrahydrofuran, toluene, diethyl ether, and 1,2-dichloroethane; in step 2, the hydroxyl-containing (meth)acrylate compound includes at least one of hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, and hydroxypropyl acrylate; and in step 3, the second organic solvent is selected from at least one of ethyl acetate, dichloromethane, diethyl ether, and toluene.

[0010] In this invention, the term "(meth)acrylate" should be interpreted broadly to mean at least one selected from "acrylate" and "methacrylate".

[0011] In another aspect, the present invention also provides a photoresist composition for OLEDs, comprising the following components in parts by weight: 12-17 parts of the acrylate cage-like oxacalixarene compound as described above, 13-15 parts of fluorene (meth)acrylate resin, 1-2 parts of photoinitiator, 0.1-0.6 parts of additives, and 60-70 parts of a third organic solvent.

[0012] Specifically, to further verify the effectiveness of the cage-like oxacalixarene compound prepared in this invention, this invention selects a fluorene-containing (meth)acrylate resin as the film-forming resin, such as Lisenlock W5001 resin or Osaka Gas 1030 resin (the main chain or side chain of this type of resin contains (meth)acrylate groups, and it is a free radical polymerization system with cage-like acrylate monomers, with good compatibility and can undergo efficient copolymerization to form a uniform and dense cross-linked network. At the same time, it has a large fused ring structure, which can improve molecular rigidity, reduce dipole orientation polarization, and achieve lower polarity) and combines it with the synthesized low-dielectric monomer (cage-like oxacalixarene compound), photoinitiator, auxiliary agent, and third organic solvent to prepare a low-dielectric photoresist composition.

[0013] The photoresist composition further includes: 0-4 parts of acrylic monomer.

[0014] Preferably, the acrylic monomer is any one of a monofunctional acrylic monomer, a difunctional acrylic monomer, or a polyfunctional acrylic monomer.

[0015] Specifically, the dielectric value of the photoresist composition is ≤2.6.

[0016] It should be noted that the weight percentages of each component in the above-mentioned OLED photoresist composition are within the range described above and can be adjusted adaptively according to actual performance requirements. For example, the weight percentages of acrylate cage-like oxacalixarene compounds can be 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, etc., and will not be listed individually; the weight percentages of fluorene (meth)acrylate resins can be 13 parts, 13.5 parts, 14 parts, 14.5 parts, 15 parts, etc., and will not be listed individually; the weight percentages of photoinitiators can be 1 part, 1.5 parts, 2 parts, etc., and will not be listed individually; the weight percentages of additives can be 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, etc., and will not be listed individually; the weight percentages of the third organic solvent can be 60 parts, 62 parts, 65 parts, 66 parts, 68 parts, 70 parts, etc., and will not be listed individually. The third organic solvent is selected from at least one of propylene glycol methyl ether, propylene glycol methyl ether acetate, cyclohexanone, and methyl ethyl ketone.

[0017] The above-mentioned method for preparing the OLED photoresist composition involves adding acrylate cage-like oxacalixarene compound, fluorene-containing (meth)acrylate resin, photoinitiator, additives, and organic solvent into a reactor according to the above-mentioned weight ratio, stirring for 30-60 minutes under light-protected conditions, and allowing it to stand for 40-80 minutes to obtain the photoresist composition.

[0018] In addition, the present invention also provides an application of the photoresist composition described above in part or all of the above in a light-emitting device. In the application, the photoresist composition is first attached to the surface of the substrate by spin coating, blade coating, screen printing or inkjet printing, followed by vacuum concentration drying (VCD), pre-baking, and then exposure through a photomask using an i-line exposure machine, followed by development to form an island pattern array.

[0019] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects: After curing, the photoresist composition of the present invention exhibits the following comprehensive excellent properties at a film thickness of about 3.5 μm: (1) Ultra-low dielectric constant: The dielectric value is stably reduced to below 2.6, which meets the stringent requirements of large-size touch devices for ultra-low dielectric constant (≤3.0), can significantly reduce parasitic capacitance, and improve touch sensitivity and signal-to-noise ratio. The core role of cage-like oxacalixarene compounds is reflected in: The rigid cage-like cavity structure of the acrylate-based cage-like oxacalixarene compounds can effectively reduce the material packing density and introduce a large amount of free volume, thereby significantly reducing the dielectric constant. At the same time, by introducing fluorine atoms into its structure (as shown in the examples), the high bond energy and low polarizability of carbon-fluorine bonds, combined with the "shielding effect" generated by the large volume of fluorine atoms, further suppress molecular polarization and synergistically achieve a significant reduction in dielectric value (≤2.6). In addition, the selected fluorene-containing (meth)acrylate resin has a large fused-ring aromatic structure with high molecular rigidity, which can effectively limit the orientation polarization of dipoles under an electric field, thereby helping to maintain a low dielectric constant.

[0020] (2) High pattern resolution: Under standard photolithography, a linewidth resolution of approximately 10 μm can be achieved, with clear pattern edges and good linewidth uniformity, meeting the fine processing requirements of high pixel density display products. Cage-like oxacalixarane compounds have clearly defined polymerizable acrylate groups, exhibiting good compatibility with fluorene-containing resins and photoinitiator systems. During exposure, they can achieve rapid and uniform photopolymerization reactions, forming high-contrast exposed and unexposed areas. By controlling the amount of photoinitiator, excessive scattering or side reactions caused by excessive initiator can be avoided, ensuring precise pattern transfer during the photolithography process, thereby obtaining patterns with sharp edges and high resolution.

[0021] (3) Excellent interfacial adhesion: At an exposure energy of 60 mJ / cm², there is no peeling phenomenon between the device and the polyimide (PSPI) pixel definition layer substrate, demonstrating excellent interfacial bonding strength and process compatibility, ensuring the structural reliability and long-term stability of the device. The unique three-dimensional structure of the cage-like oxacalixarene compound can generate a stronger physical interlocking effect at the interface with the PSPI substrate. At the same time, the polar groups (such as ester groups) in its molecule can form strong van der Waals forces and even hydrogen bonds with the functional groups on the PSPI surface, thereby greatly improving the interfacial bonding force and avoiding peeling during development or subsequent processes.

[0022] (4) Good overall processability: The photoresist composition forms a uniform film with good thermal stability, is suitable for large-area homogenization preparation, and has good prospects for industrial application.

[0023] The synergistic effect of the above-mentioned OLED photoresist composition is manifested in the following aspects: the composition uses 12-17 parts of cage-like oxacalixarene compounds and 13-15 parts of fluorene-containing resin as the film-forming and functional host, forming a homogeneous and stable system in 60-70 parts of a third organic solvent. This formulation ensures the full function of the low-dielectric monomers, while providing sufficient film-forming properties and mechanical strength through the resin. Additives (0.1-0.5 parts) further improve leveling properties and interfacial characteristics. Through the synergistic effect of each component, the entire system achieves an optimal balance in terms of molecular rigidity, free volume, polarizability, polymerization activity, and interfacial properties, thereby simultaneously achieving ultra-low dielectric, high resolution, and strong adhesion.

[0024] This invention, through meticulous molecular design and component synergy, provides an ideal dielectric material solution for next-generation high-performance, large-size OLED touch display devices. By optimizing the proportions of functional monomers with specific cage-like structures and fluorination modifications, high-rigidity fluorene-containing (meth)acrylate resins, and other components, the invention addresses three core issues at the molecular scale: material polarizability, photosensitivity, and interfacial compatibility (high dielectric value, insufficient patterning resolution, and weak adhesion on critical substrates such as PSPI). Ultimately, a low-dielectric photoresist material with excellent overall performance is obtained, providing a key material solution for the advancement of next-generation OLED touch display technology. Attached Figure Description

[0025] The accompanying drawings are incorporated in and form part of this specification, and together with the description serve to explain the principles of the invention.

[0026] Figure 1 shows the resolution of the thin film prepared on a glass substrate using the photoresist prepared in Example 1 after exposure and development; Figure 2 shows the OM image of the thin film prepared on a PIPS substrate using the photoresist prepared in Example 1 after exposure and development at an energy of 60 mJ / cm²; Figure 3 shows the OM image of the thin film prepared on a PIPS substrate using the photoresist prepared in Comparative Example 3 after exposure and development at an energy of 60 mJ / cm². Detailed Implementation

[0027] Exemplary embodiments will now be described in detail. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples consistent with some aspects of the invention as detailed in the appended claims.

[0028] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0029] The method for preparing cage-like oxacalixarenes Cage-6c with conjugated benzoic acid groups is as follows: 0.4 g of methyl benzoate-substituted cage-like oxacalixarene Cage-6Me was weighed into a 250 mL round-bottom flask. 20 mL of 1,4-dioxane and 80 mL of an aqueous solution containing 4.48 g of potassium hydroxide were added. The resulting mixed solution A was refluxed at 110 °C for 24 h. After the reaction was complete, the solvent was evaporated, and the residue was dissolved in 100 mL of water. Concentrated hydrochloric acid was gradually added dropwise until the pH of the solution reached 2. The mixture was filtered, and the white precipitate collected was the cage-like oxacalixarene Cage-6c (0.33 g, yield 91.6%) conjugated with benzoic acid groups. The characterization data of this cage-like oxacalixarene Cage-6c conjugated with benzoic acid groups are as follows: 1 H NMR (600 MHz, DMSO-d6, 298 K)δ(ppm): 12.99 (s, 6H), 8.15 (s, 3H), 8.01 (d,J= 8.19 Hz, 12H), 7.94 (d,J= 8.16 Hz, 12H), 6.96 (s,6H), 13 C NMR (600MHz, DMSO-d6, 298 K)δ(ppm): 167.54, 158.60, 154.84, 139.78, 130.18, 129.74,117.01, 116.01, 66.86.

[0030] The cage-like oxacalixarene Cage-6Cl, conjugated with benzoyl chloride, is synthesized as follows: Weigh 1.98 g (0.01 mol, 1 eq.) of benzoic acid-substituted cage-like oxacalixarene Cage-6C into a 500 mL round-bottom flask, add 200 mL of dry dichloromethane solution, and cool to 0 °C; then slowly add 11.9 g of SOCl2 (0.1 mol, 10 eq.), react at room temperature for 12 h, and after the reaction is complete, evaporate the solvent and collect the white solid, which is 11.56 g (yield 88.3%) of cage-like oxacalixarene Cage-6Cl conjugated with benzoyl chloride.

[0031] Preparation Example 1 This preparation example provides a cage-like oxacalixarene compound, Cage-5-1, conjugated with benzoic acid and methacrylic acid, which is synthesized as follows: Weigh 3.09 g (0.01 mol, 1 eq.) of the prepared cage-like oxacalixarene conjugated with benzoyl chloride into a 500 mL round-bottom flask, add 200 mL of dry dichloromethane solution and 8.2 mL of dry triethylamine (0.06 mol, 6 eq.), cool to 0 °C, and then slowly add 34.8 mL of hydroxyethyl methacrylate (0.052 mol, 5.2 eq.). After the reaction is complete, react at room temperature for 6 h. After the reaction is complete, add water to quench the reaction, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, and evaporate the solvent. The crude product is purified by column chromatography (eluent: ethyl acetate / methanol = 10:1, v / v) to obtain the cage-like oxacalixarene compound Cage-5-1 conjugated with benzoic acid and methacrylic acid, with a yield of 82%, i.e., X in formula (1) adopts the substituent shown in formula (2).

[0032] Preparation Example 2 This preparation example provides a cage-like oxacalixarene compound Cage-5-2 conjugated with benzoic acid and acrylic acid, i.e., X in formula (1) adopts the substituent shown in formula (3).

[0033] The difference from Preparation Example 1 is that 0.052 mol of hydroxyethyl methacrylate was replaced with 0.52 mol of hydroxyethyl acrylate.

[0034] Preparation Example 3 This preparation example provides a cage-like oxacalixarene compound Cage-5-3 conjugated with benzoic acid and fluoroacrylic acid, i.e., X in formula (1) adopts the substituent shown in formula (4).

[0035] The difference from Preparation Example 1 is that 0.052 mol of hydroxyethyl methacrylate was replaced with 0.52 mol of hydroxyethyl fluoroacrylate.

[0036] Preparation Example 4 This preparation example provides a cage-like oxacalixarene compound Cage-5-4 conjugated with benzoic acid and trifluoromethacrylic acid, i.e., X in formula (1) adopts the substituent shown in formula (5).

[0037] The difference from Preparation Example 1 is that 0.052 mol of hydroxyethyl methacrylate was replaced with 0.52 mol of hydroxyethyl trifluoromethacrylate.

[0038] The mass fractions of the above-mentioned raw materials are shown in Table 1 below. The preparation of the low-dielectric photoresist composition specifically includes: adding the raw materials to a reaction vessel according to the corresponding weight fractions, mixing and stirring with a stirrer, stirring for 30-60 minutes under light-protected conditions, and then letting it stand for 40-80 minutes to obtain the low-dielectric photoresist composition. The composition includes 12-17 parts of acrylate cage-like oxacalixarene compound, 0-4 parts of acrylic monomer, 13-15 parts of fluorene-containing (meth)acrylate resin, 1-2 parts of photoinitiator, 0.1-0.6 parts of additives, and 60-70 parts of a third organic solvent.

[0039] It should be noted that the acrylic monomer can be any one of monofunctional acrylic monomers, difunctional acrylic monomers, or multifunctional acrylic monomers to provide support for achieving the specific functions of the membrane surface.

[0040] Table 1 Example 1 This example provides a low-dielectric photoresist composition (I), in which the following raw materials are weighed according to the corresponding weight parts: 13.6 parts of Lisenlock W5001 resin containing fluorene structure, 16.7 parts of cage-like oxacalixarene compound Cage-5-2 obtained in Preparation Example 2, 2.1 parts of photoinitiator OXE-01, 0.3 parts of additives BYK801 and BYK503, and 67 parts of propylene glycol methyl ether acetate.

[0041] Add the above raw materials into a reaction vessel, mix and stir with a stirrer, stir for 30-60 minutes under light-protected conditions, and let stand for 40-80 minutes to obtain the low-dielectric photoresist composition (I).

[0042] Example 2 is based on Example 1. This example provides a low-dielectric photoresist composition (II). The difference from Example 1 is that the cage-like oxacalixarene compound is Cage-5-3 obtained in Preparation Example 3, and the weight part is still 16.7 parts; the other raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0043] Example 3 is based on Example 1. This example provides a low-dielectric photoresist composition (III). The difference from Example 1 is that the cage-like oxacalixarene compound is Cage-5-4 obtained in Preparation Example 4, and the weight part is still 16.7 parts; the other raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0044] Example 4, based on Example 1, provides a low-dielectric photoresist composition (fourth type), which differs from Example 1 in that: 14.5 parts of Osaka Gas 1030 resin containing fluorene structure are used; 15.8 parts by weight of Cage-5-4 obtained in Preparation Example 4 are used; and 67 parts by weight of propylene glycol methyl ether is used as the organic solvent. The remaining raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0045] Example 5 is based on Example 1. This example provides a low-dielectric photoresist composition (V). The difference from Example 1 is that the cage-like oxacalixarene compound is Cage-5-4 obtained in Preparation Example 4, with a weight of 12.7 parts, and the weight of pentaerythritol triacrylate PETA is 4 parts. The remaining raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0046] Example 6 is based on Example 1. This example provides a low-dielectric photoresist composition (six), which differs from Example 1 in that: the cage-like oxacalixarene compound used is Cage-5-1 obtained in Preparation Example 1, with a weight of 16.7 parts. The other raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0047] Comparative Example 1: Based on Example 1, this comparative example provides a photoresist composition (seven). The difference from Example 1 is that the cage-like oxacalixarene compound Cage-5-2 is replaced with bisquaternary DPHA (dipentaerythritol hexaacrylate). The remaining raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0048] Comparative Example 2 provides a photoresist composition (eight) based on Example 1. The difference from Example 1 is that the cage-like oxacalixarene compound Cage-5-2 is replaced with Cage-5-1, and DPHA (dipentaerythritol hexaacrylate) is added in 3.7 parts by weight. The remaining raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0049] Comparative Example 3 provides a photoresist composition (IX) based on Example 1. The difference from Example 1 is that the amount of the fluorene-containing Lisenlock W1002 resin is 14.5 parts, and the cage-like oxacalixarene compound Cage-5-2 is replaced with Cage-5-3 in 15.8 parts by weight. The remaining raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0050] Comparative Example 4 provides a photoresist composition (x) based on Example 1. The difference from Example 1 is that the amount of the fluorene-containing Lisenlock W5001 resin is 14.5 parts, the cage-like oxacalixarene compound Cage-5-2 is replaced with Cage-5-3 at a weight of 15.8 parts, the amount of photoinitiator OXE-01 is 4.1 parts, and the remaining raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0051] Comparative Example 5 provides a photoresist composition (XI) based on Example 1. The difference from Example 1 is that the resin used is a 9,9-bis(4-hydroxyphenyl)fluorene-derived epoxy resin, and the other raw materials and their amounts, as well as the preparation process, are the same as in Example 1.

[0052] The photoresist compositions prepared in Examples 1-6 and Comparative Examples 1-5 were spin-coated onto ITO conductive glass, polyimide (PSPI) substrates, or blank glass. After vacuum concentration drying (VCD), pre-baking at 85°C, exposure was performed using an i-line exposure machine through a photomask, followed by development to form an island pattern array, or exposure was performed without a photomask, followed by development to form a cured photoresist film. The film thickness was controlled to be 3.5 μm, and performance testing was performed, specifically including the following aspects: (1) Dielectric value: A silver electrode with a diameter of 18 mm was deposited on the photoresist film on the ITO conductive glass using an evaporation machine. The dielectric value C of the photoresist was tested using a WK6500B impedance analyzer from the UK. Then, the dielectric value was calculated based on the film thickness d and the electrode area S. The calculation formula is as follows: (2) Resolution: The highest resolution of the above-mentioned island and hole area pattern array observed using a microscope.

[0053] (3) PSPI adhesion: For the island pattern array on the above polyimide (PSPI) substrate, the minimum exposure energy required to maintain the 25μm island area without detachment is recorded as the PSPI adhesion of the composition. The lower the value, the better the adhesion performance and photosensitivity of the material on PSPI.

[0054] The performance results of the photoresist compositions in Examples 1-6 and Comparative Examples 1-5, after testing, are shown in Table 2 below: Table 2 In summary, based on the data in Table 2 and the test results, the low-dielectric photoresists prepared in Examples 1-5 of this invention all meet the dielectric value standard (≤2.6). Furthermore, as the fluorine content in the low-dielectric monomer increases, the carbon-fluorine bond energy is high, the polarizability is low, and the fluorine atom volume is large, forming a "shielding effect" that further reduces the dielectric value. The low-dielectric photoresist prepared in Example 1 has a resolution of about 10 μm, as shown in Figure 1. Moreover, the PSPI adhesion can be guaranteed to remain intact under exposure at 60 mJ / cm², as shown in Figure 2.

[0055] In contrast, Comparative Example 1, lacking a low-dielectric monomer—a cage-like oxacalixarene compound containing both carboxyl and acrylate structures—relyed solely on a low-dielectric resin, failing to meet the low-dielectric (≤2.6) requirement; Comparative Example 2, due to insufficient low-dielectric monomer usage, also failed to meet the dielectric requirement; Comparative Example 3, using a long-chain acrylic resin, lacked a network structure with numerous cavities, resulting in an unacceptable dielectric value. The photoresist prepared on a PIPS substrate, after exposure and development at 60 mJ / cm², showed OM image detachment, as shown in Figure 3; Comparative Example 4, with an excessively high photoinitiator ratio, resulted in insufficient overall resolution, but exhibited good PSPI adhesion. Comparative Example 5: Although the epoxy resin derived from 9,9-bis(4-hydroxyphenyl)fluorene contains a fluorene structure, its reaction mechanism is different from that of the cage-like acrylate monomer system in the formulation. It forms a network such as ether bonds through cationic ring-opening polymerization or thermal curing with the curing agent, resulting in a decrease in the resolution and PSPI adhesion of the final cured film (exposure energy up to 100 mJ / cm²).

[0056] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention.

[0057] It should be understood that the present invention is not limited to the content already described above, and various modifications and changes can be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. An acrylate cage-like oxacalixarene compound, characterized in that, The acrylate cage-like oxacalixarene compounds are conjugated with carboxylic acid esters and acrylate groups, and their specific general structural formula is shown in formula (1) below: In formula (1), X is selected from acrylate groups containing phenyl groups that are substituted or unsubstituted by fluorine atoms, trifluoromethyl or fluorinated alkyl groups.

2. The acrylate cage-like oxacalixarene compound according to claim 1, characterized in that, X is any of the substituents shown in equations (2) to (5): 。 3. The method for preparing acrylate cage-like oxacalixarene compounds as described in claim 1 or 2, characterized in that, Includes the following steps: Step 1: In a first organic solvent, a cage-like oxacalixarene compound with acyl chloride groups is mixed with an organic base to form reaction mixture A; Step 2: After cooling reaction mixture A to 0-10°C, a hydroxyl-containing (meth)acrylate compound is added to reaction mixture A, and then the temperature is raised to room temperature until the reaction is complete; Step 3: After the reaction is complete, the reaction is quenched with water, the product is extracted with a second organic solvent, and the crude product is obtained after drying and concentrating the organic phase; Step 4: The crude product is purified by column chromatography to obtain a cage-like oxacalixarene compound with conjugated carboxylic acid ester and acrylate groups.

4. The preparation method according to claim 3, characterized in that, In step 1, the first organic solvent is selected from at least one of dichloromethane, tetrahydrofuran, toluene, diethyl ether, and 1,2-dichloroethane; in step 2, the hydroxyl-containing (meth)acrylate compound includes at least one of hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, and hydroxypropyl acrylate; in step 3, the second organic solvent is selected from at least one of ethyl acetate, dichloromethane, diethyl ether, and toluene.

5. A photoresist composition for OLEDs, characterized in that, It includes the following components in parts by weight: The mixture comprises 12-17 parts of the acrylate cage-like oxacalixarene compound as described in claim 1 or 2, 13-15 parts of the fluorene (meth)acrylate resin, 1-2 parts of the photoinitiator, 0.1-0.6 parts of the additives, and 60-70 parts of the third organic solvent.

6. The photoresist composition for OLEDs according to claim 5, characterized in that, Also includes: 0-4 parts of acrylic monomer.

7. The photoresist composition for OLEDs according to claim 6, characterized in that, The acrylic monomer is any one of monofunctional acrylic monomer, difunctional acrylic monomer, or polyfunctional acrylic monomer.

8. The photoresist composition for OLEDs according to claim 5, characterized in that, The dielectric value of the photoresist composition is ≤2.

6.

9. A method for preparing an OLED photoresist composition according to any one of claims 5 to 8, characterized in that, Acrylic cage-like oxacalixarene compound, calixarene compound, fluorene-containing (meth)acrylate resin, photoinitiator, additives and organic solvent are added to the reactor in the above weight ratio, and stirred for 30-60 min under light-protected conditions. After standing for 40-80 min, the photoresist composition is obtained.

10. The application of the photoresist composition according to any one of claims 4 to 7 in a light-emitting device, characterized in that, In application, the photoresist composition is first attached to the substrate surface by spin coating, scraping, screen printing or inkjet printing, and then pre-baking, exposure and development are performed to form an island pattern array.

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