Nanoimprint glue and preparation method thereof

Abstract

This application provides a nanoimprinting adhesive and its preparation method. By mass percentage, the nanoimprinting adhesive comprises 10-20% high-refractive-index monomer, 5-10% acrylate prepolymer, 5-10% nano-hybridized acrylate prepolymer, 20-35% inorganic nanoparticles, 3-5% photoinitiator, 1-5% coupling agent, and 15-55% solvent; the high-refractive-index monomer has the structure shown in Formula I. The nanoimprinting adhesive possesses high refractive index, excellent mechanical strength, excellent high-temperature resistance, and good flowability. When used in nanoimprinting technology, it yields products with high appearance yield and good performance, meeting various nanoimprinting process requirements and enabling large-scale mass production.

Description

Technical Field

[0001] This application belongs to the field of optical materials technology, specifically relating to a nanoimprint adhesive and its preparation method. Background Technology

[0002] Nanoimprint lithography is a technique that uses photoresist to transfer micro- and nano-structures from a template onto a substrate. The nanoimprinting adhesive acts as a "medium" for pattern transfer; the nano-pattern on the template interacts with the adhesive, replicating it proportionally. Then, etching and other pattern transfer techniques are used to transfer the pattern from the adhesive to the substrate. Early techniques included thermal nanoimprint lithography, which involved pressing a template with micro- and nano-structures onto a substrate coated with an imprinting adhesive under high temperature and pressure. The flowing adhesive filled the template pattern, and cooling cured the adhesive. Thermal nanoimprint lithography is less demanding on the adhesive, often using thermoplastic polymers such as polymethyl methacrylate (PMMA). However, the high temperature and pressure can cause unintended deformations in the adhesive, template, and substrate, affecting pattern transfer performance and template reusability.

[0003] Currently, the mainstream approach uses UV-curable nanoimprint colloids. The principle involves using a low-viscosity polymer sensitive to UV light as the imprinting adhesive. At room temperature, the colloid fills the template cavity and then rapidly cures upon UV irradiation. Nanoimprint technology has developed rapidly in recent years and shows great promise for applications in optics, displays, and other fields.

[0004] However, while UV nanoimprinting adhesives cure quickly, incomplete curing can occur, affecting the mechanical properties of the microstructure. This can lead to breakage and residual adhesive during demolding, and reliability testing may reveal varying degrees of structural damage or detachment. Furthermore, the organic components of the adhesive have a low refractive index, which is primarily increased by adding inorganic particles. However, excessively high particle content weakens the adhesive's fluidity, preventing proper filling of the template's micro / nanostructures during imprinting. This results in dimensional deformation or significant parameter variations, impacting optical performance. Additionally, the adhesive exhibits poor high-temperature resistance; microstructure collapse can occur after high-temperature baking or high-temperature reliability testing, similarly affecting optical performance. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this application is to provide a nanoimprinting adhesive and its preparation method. The nanoimprinting adhesive possesses high refractive index, excellent mechanical strength, excellent high-temperature resistance, and good flowability. When used in nanoimprinting technology, it yields products with high appearance yield and good performance, meeting various nanoimprinting process requirements and enabling large-scale mass production.

[0006] To achieve this objective, the following technical solution is adopted in this application:

[0007] In a first aspect, this application provides a nanoimprinting adhesive, which, by mass percentage, comprises 10-20% high refractive index monomer, 5-10% acrylate prepolymer, 5-10% nano-hybrid modified acrylate prepolymer, 20-35% inorganic nanoparticles, 3-5% photoinitiator, 1-5% coupling agent, and 15-55% solvent; the high refractive index monomer has the structure shown in Formula I.

[0008] Formula I.

[0009] In Formula I, R1 and R2 are each independently selected from any one of substituted or unsubstituted C6~C30 aryl, substituted or unsubstituted C3~C30 heteroaryl, substituted or unsubstituted C6~C30 arylthio, and substituted or unsubstituted C3~C30 heteroarylthio.

[0010] R3, R4, R5, R6, R7, and R8 are each independently selected from H and any one of the C1-C10 straight-chain or branched alkyl groups, whether substituted or unsubstituted.

[0011] n1 and n2 are each independently selected from integers ≥1.

[0012] The substituents include at least one of hydroxyl, amino, C1-C6 straight-chain or branched alkyl, C6-C20 aryl, and C3-C20 heteroaryl.

[0013] In this application, the high-refractive-index monomer adopts a specific structural design, possessing a high refractive index and glass transition temperature (Tg). This improves the refractive index of the organic components in the nanoimprint adhesive, reduces the amount of inorganic nanoparticles added, ensures good flowability of the nanoimprint adhesive, avoids structural dimensional deformation or large parameter changes during imprinting, and improves product yield while reducing costs. Furthermore, the high-refractive-index monomer can effectively participate in curing, forming a macromolecular cross-linked network, which improves the mechanical strength and high-temperature resistance of the nanoimprint adhesive, helps improve the mechanical properties of the microstructure, avoids microstructure collapse or deformation, and reduces problems such as tearing, detachment, and residue during imprinting and reliability testing. Moreover, using a specific structure of refractive-index monomer in combination with acrylate prepolymer, nano-hybrid modified acrylate prepolymer, and inorganic nanoparticles in specific proportions further enhances the mechanical strength, high-temperature resistance, and flowability of the nanoimprint adhesive.

[0014] In this application, 10-20% of the high refractive index monomer can be, for example, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, etc.

[0015] In this application, 5-10% acrylate prepolymer, for example, can be 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, etc.

[0016] In this application, 5-10% of nano-hybrid modified acrylate prepolymer can be, for example, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, etc.

[0017] In this application, 20-35% are inorganic nanoparticles, for example, 22%, 24%, 26%, 28%, 30%, 32%, 34%, etc.

[0018] In this application, 3-5% photoinitiator, for example, can be 3.2%, 3.5%, 3.8%, 4%, 4.2%, 4.5%, 4.8%, etc.

[0019] In this application, the coupling agent is 1-5%, for example, it can be 1.2%, 1.5%, 1.8%, 2%, 2.2%, 2.5%, 2.8%, 3%, 3.2%, 3.5%, 3.8%, 4%, 4.2%, 4.5%, 4.8%, etc.

[0020] In this application, the solvent is 15-55%, for example, it can be 16%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35%, 38%, 40%, 42%, 45%, 48%, 50%, 52%, 54%, etc.

[0021] In this application, the C6~C30 aryl refers to an aryl group with 6 to 30 carbon atoms, such as C6, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30 aryl, etc.; the same expression in the following text has the same meaning.

[0022] In this application, the C6-C30 aryl group can be a fused-ring aryl group or a monocyclic aryl group. For example, the C6-C30 aryl group includes, but is not limited to, phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthryl, indene, fluorenyl, fluoranyl, triphenylene, pyrene, perylene, and tetraphenyl, etc.; the same expressions in the following text have the same meaning.

[0023] In this application, the C3~C30 heteroaryl refers to a heteroaryl group with 3 to 30 carbon atoms, such as C3, C4, C5, C6, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30 heteroaryl, etc.; the same expression in the following text has the same meaning.

[0024] In this application, the C3-C30 heteroaryl group can be a fused-ring heteroaryl group or a monocyclic heteroaryl group; exemplaryly, the C3-C30 heteroaryl group includes, but is not limited to, furanyl, thiophene, pyrrole, pyridyl, benzofuranyl, benzothiophene, isobenzofuranyl, indolyl, dibenzofuranyl, dibenzothiophene, carbazole, acridineyl, isobenzofuranyl, isobenzothiophene, benzocarbazole, etc.; the same expressions below have the same meaning.

[0025] In this application, the C6~C30 arylthio group refers to an arylthio group with 6 to 30 carbon atoms, such as C6, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30 arylthio groups, etc.; the same expression in the following text has the same meaning.

[0026] In this application, the C3~C30 heteroarylthio group refers to a heteroarylthio group with 3 to 30 carbon atoms, such as C3, C4, C5, C6, C8, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30 heteroarylthio groups, etc.; the same expression in the following text has the same meaning.

[0027] In this application, the C6~C30 arylthio group and C3~C30 heteroarylthio group refer to the groups formed by the aforementioned aryl or heteroaryl groups with O or S; if the same expression is used below, it has the same meaning.

[0028] In this application, the C1-C10 straight-chain or branched alkyl groups refer to straight-chain or branched alkyl groups with 1 to 10 carbon atoms, such as C1, C2, C3, C4, C5, C6, C8, and C10 straight-chain or branched alkyl groups. Exemplarily, the C1-C10 straight-chain or branched alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, neopentyl, n-hexyl, neohexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl. The same expressions in the following text have the same meaning.

[0029] In this application, the C1-C6 straight-chain or branched alkyl groups refer to straight-chain or branched alkyl groups with 1 to 6 carbon atoms, such as C1, C2, C3, C4, C5, and C6 straight-chain or branched alkyl groups. Exemplarily, the C1-C6 straight-chain or branched alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, neopentyl, n-hexyl, and neohexyl. The same expressions in the following text have the same meaning.

[0030] In this application, the C6~C20 aryl refers to an aryl group with 6 to 20 carbon atoms, such as C6, C8, C10, C12, C14, C16, C18, C20 aryl, etc.; the same expression in the following text has the same meaning.

[0031] In this application, the C6-C20 aryl group can be a fused-ring aryl group or a monocyclic aryl group. For example, the C6-C20 aryl group includes, but is not limited to, phenyl, biphenyl, terphenyl, naphthyl, anthracene, indene, fluorenyl, fluoranthyl, triphenylene, pyrene, perylene, etc.; the same expressions in the following text have the same meaning.

[0032] In this application, the C3~C20 heteroaryl refers to a heteroaryl group with 3 to 20 carbon atoms, such as C3, C4, C5, C6, C8, C10, C12, C14, C16, C18, C20 heteroaryl, etc.; the same expression in the following text has the same meaning.

[0033] In this application, the C3-C20 heteroaryl group can be a fused-ring heteroaryl group or a monocyclic heteroaryl group; exemplaryly, the C3-C20 heteroaryl group includes, but is not limited to, furanyl, thiophene, pyrrole, pyridyl, benzofuranyl, benzothiophene, isobenzofuranyl, indolyl, dibenzofuranyl, dibenzothiophene, carbazole, acridineyl, isobenzothiophene, benzocarbazole, etc.; the same expressions below have the same meaning.

[0034] In this application, R1 and R2 are each independently selected from any one of substituted or unsubstituted C6-C20 aryl, substituted or unsubstituted C3-C20 heteroaryl, substituted or unsubstituted C6-C20 arylthio, and substituted or unsubstituted C3-C20 heteroarylthio; the substituted substituents include at least one of hydroxyl, amino, C1-C6 straight-chain or branched alkyl, C6-C20 aryl, and C3-C20 heteroaryl.

[0035] In this application, when R1 and R2 are each independently selected from substituted or unsubstituted C3~C30 heteroaryl groups, heteroaryl groups containing S are more preferred.

[0036] In this application, R1 and R2 are each independently selected from any one of the following groups, or any one of the following groups substituted by a substituent.

[0037]

[0038] R is selected from C1~C6 straight-chain or branched alkyl groups.

[0039] The substituents include at least one of hydroxyl, amino, C1-C6 straight-chain or branched alkyl, C6-C20 aryl, and C3-C20 heteroaryl.

[0040] “ "" indicates a connection point.

[0041] In this application, R3, R4, R5, R6, R7, and R8 are each independently selected from H or methyl.

[0042] The values ​​of n1 and n2 are each 1 independently.

[0043] In this application, the high refractive index monomer includes at least one of the following compounds.

[0044] , , , .

[0045] In this application, the refractive index of the high refractive index monomer is ≥1.6, for example, it can be 1.62, 1.64, 1.66, 1.68, 1.7, 1.72, 1.74, 1.76, 1.78, 1.8, 1.82, 1.84, etc.

[0046] In this application, the glass transition temperature of the high refractive index monomer is ≥100℃, for example, it can be 100℃, 102℃, 104℃, 106℃, 108℃, 110℃, 112℃, 114℃, 116℃, 118℃, 120℃, etc.

[0047] In this application, the viscosity of the high refractive index monomer at 25°C is 25,000~40,000 mPa•s, for example, it can be 25,500 mPa•s, 26,000 mPa•s, 27,000 mPa•s, 28,000 mPa•s, 29,000 mPa•s, 30,000 mPa•s, 32,000 mPa•s, 34,000 mPa•s, 36,000 mPa•s, 38,000 mPa•s, etc.

[0048] In this application, the appearance of the same substituent number in different structural formulas or in the same structural formula does not necessarily mean that the two are the same; they can be the same or different.

[0049] In this application, the high refractive index monomer is prepared by the following method, the method comprising:

[0050] (1) Compound A reacts with compound B to give the first product;

[0051] (2) The first product was reacted with 1,4-dithiohexacyclo-2,5-dithiol to obtain the second product;

[0052] (3) The second product is reacted with compound D to obtain the high refractive index monomer.

[0053] The compound A has the structure shown in Formula A: R-SH Formula A.

[0054] The compound B has the structure shown in formula B: Formula B.

[0055] The compound D has the structure shown in formula D: Formula D.

[0056] In Formula A, R is selected from the same range as R1 or R2 in Formula I.

[0057] In formula B, n is selected from integers ≥1, such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc.

[0058] In formula B or formula D, X is selected from halogens; the halogens refer to F, Cl, Br, I, and more preferably Cl.

[0059] In formula D, , , Each is independently selected from the same range of constraints as R3, R4, R5, R6, R7 or R8 in Equation I.

[0060] In this application, the structural formula of the first product is as follows: The structural formula of the second product is: .

[0061] In this application, the molar ratio of compound A to compound B in step (1) is 1:(1.1~1.5), for example, it can be 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, etc.

[0062] In this application, the reaction in step (1) is carried out in the presence of a solvent and a catalyst; the solvent includes, but is not limited to, toluene; the catalyst includes, but is not limited to, an organic strong base catalyst, exemplary including, but not limited to, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU); with a molar content of compound A of 100 mmol, the molar content of the catalyst is 60~100 mmol, for example, it can be 65 mmol, 70 mmol, 75 mmol, 80 mmol, 85 mmol, 90 mmol, 95 mmol, etc.

[0063] In this application, the reaction in step (1) includes: mixing compound A with a catalyst and a solvent and stirring for 20-40 min, then slowly adding compound B dropwise, reacting at room temperature for 12-20 h, then removing volatiles under reduced pressure, diluting the residue with an organic solvent (such as dichloromethane), washing with hydrochloric acid, distilled water and brine in sequence, drying with anhydrous sodium sulfate, and then filtering, concentrating under reduced pressure, purifying with silica gel column, and eluting to obtain a colorless, low-viscosity liquid, which is the first product.

[0064] In this application, the molar ratio of the first product to 1,4-dithiohexacyclo-2,5-dithiol in step (2) is 1:(0.4~0.5), for example, it can be 1:0.42, 1:0.44, 1:0.46, 1:0.48, etc.

[0065] In this application, the reaction in step (2) is carried out in the presence of a solvent and a catalyst; the solvent includes, but is not limited to, toluene; the catalyst includes strong organic base catalysts, exemplary including but not limited to 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU); with a molar content of 50 mmol of 1,4-dithiohexacyclo-2,5-dithiol, the molar content of the catalyst is 50~60 mmol, for example, it can be 52 mmol, 54 mmol, 56 mmol, 58 mmol, etc.

[0066] In this application, the reaction in step (2) includes: mixing 1,4-dithiohexacyclo-2,5-dithiol with a catalyst and a solvent and stirring for 20-40 min, then slowly adding the first product dropwise, reacting at room temperature for 15-25 h, then removing the volatiles under reduced pressure, diluting the residue with an organic solvent (such as dichloromethane), and washing it sequentially with hydrochloric acid, distilled water and brine, drying it with anhydrous sodium sulfate, and then filtering, concentrating under reduced pressure, purifying with silica gel column and eluting to obtain a slightly yellow viscous liquid, which is the second product.

[0067] In this application, the molar ratio of the second product to compound D in step (3) is 1:(2.1~2.5), for example, it can be 1:2.2, 1:2.3, 1:2.4, etc.

[0068] In this application, the reaction in step (3) is carried out in the presence of a catalyst, an acid-binding agent, an antioxidant, and a solvent; the catalyst includes 4-dimethylaminopyridine (DMAP), and the molar content of the catalyst is 2.5~4.5 mmol based on the molar content of the second product being 35 mmol, for example, 2.6 mmol, 2.8 mmol, 3 mmol, 3.2 mmol, 3.4 mmol, 3.6 mmol, 3.8 mmol, 4 mmol, 4.2 mmol, 4.4 mmol, etc.; the acid-binding agent includes triethylamine, and the molar content of the acid-binding agent is 150~200 mmol based on the molar content of the second product being 35 mmol, for example, 160 mmol, 170 mmol, 180 mmol, 190 mmol, etc.; the antioxidant includes butylated hydroxytoluene (BHT), and the molar content of the antioxidant is 1.5~2 mmol based on the molar content of the second product being 35 mmol, for example, 1.6 mmol, 1.7 mmol, etc. mmol, 1.8 mmol, 1.9 mmol, etc.; the solvent includes dichloromethane.

[0069] In this application, the reaction in step (3) includes: mixing and stirring the second product, acid-binding agent, antioxidant and solvent in the presence of a protective atmosphere (such as argon) for 20-40 min, then adding compound D and catalyst in sequence, reacting at room temperature for 15-25 h, then removing volatiles under reduced pressure, diluting the residue with an organic solvent (such as dichloromethane), washing it in sequence with hydrochloric acid, distilled water and brine, drying it with anhydrous sodium sulfate, and then filtering, concentrating under reduced pressure, purifying with silica gel column and eluting to obtain a colorless to slightly yellow viscous liquid, which is the high refractive index monomer.

[0070] In this application, the 1,4-dithiohexacyclo-2,5-dithiol is prepared by the following method, which includes:

[0071] (S1) 1,4-Dithiohexacyclo-2,5-diol reacts with compound E to give a third product;

[0072] (S2) The third product is reacted with compound F to give the fourth product;

[0073] (S3) The fourth product is subjected to a hydrolysis reaction to obtain the 1,4-dithiohexacyclic-2,5-dithiol.

[0074] The compound E has the structure shown in formula E: Formula E.

[0075] The compound F has the structure shown in formula F: Formula F.

[0076] In formula E or formula F, Selected from C1~C10 straight-chain or branched alkyl groups.

[0077] In this application, the structural formula of the third product is as follows: The structural formula of the fourth product is: .

[0078] In this application, the reaction described in step (S1) is carried out in the presence of a protective atmosphere, which includes argon.

[0079] In this application, the molar ratio of 1,4-dithiohexacyclo-2,5-diol to compound E in step (S1) is 1:(2.1~2.5), for example, it can be 1:2.2, 1:2.3, 1:2.4, etc.

[0080] In this application, the reaction in step (S1) is carried out in a solvent, which includes anhydrous pyridine.

[0081] In this application, the reaction in step (S1) includes: mixing 1,4-dithiohexacyclo-2,5-diol with a solvent, lowering the system temperature to 0°C, then adding compound E, stirring, precipitating a precipitate, and after the precipitate has completely precipitated, washing and recrystallizing to obtain the third product.

[0082] In this application, the molar ratio of the third product to compound F in step (S2) is 1:(2.2~3), for example, it can be 1:2.4, 1:2.6, 1:2.7, etc.

[0083] In this application, the reaction in step (S2) is carried out in the presence of a protective atmosphere, which includes argon.

[0084] In this application, the reaction in step (S2) is carried out in the presence of a solvent and a catalyst, wherein the solvent includes dichloromethane; the catalyst includes a boron trifluoride diethyl ether complex, and based on the mass of the third product being 4.16 g, the volume of the catalyst is 0.1~0.5 mL, for example, 0.12 mL, 0.15 mL, 0.18 mL, 0.2 mL, 0.25 mL, 0.3 mL, 0.35 mL, 0.4 mL, 0.45 mL, etc.

[0085] In this application, the reaction in step (S2) includes: mixing the third product with a solvent, lowering the system temperature to 0°C, stirring for 5-20 min, then adding compound F, stirring for 5-20 min, adding a catalyst, reacting at -12 to -2°C for 0.5-4 h, then reacting at 0°C for 0.5-4 h, and finally stirring at room temperature for 2-8 h to precipitate a precipitate. After the precipitate has completely precipitated, it is quenched, washed, filtered, rotary evaporated, and recrystallized to obtain the fourth product.

[0086] In this application, the hydrolysis reaction in step (S3) is carried out under acidic conditions, specifically including: mixing the fourth product with a solvent, adding a mixed solution of acid and alcohol to it, reacting at 50~70℃ for 12~20h, concentrating, purifying by chromatography column, and drying to obtain the 1,4-dithiohexacyclic-2,5-dithiol; the volume ratio of acid to alcohol in the mixed solution of acid and alcohol is 1:(10~20), for example, it can be 1:12, 1:14, 1:16, 1:18, etc.

[0087] In this application, the acrylate prepolymer includes at least one of polyurethane acrylate prepolymer, polyester acrylate prepolymer, and epoxy acrylate prepolymer.

[0088] In this application, the acrylate prepolymer can be commercially available. For example, the acrylate prepolymer includes, but is not limited to, one or more of the following: Kunshan Castel's 9537; Changxing Materials' 6151, DR-U084, DR-U299, DR-U379, DR-U384, DR-U388, 6371, and 6372; Meiyuan's HR6100, HR6200, PS4500, PS4040, and PS610; and Sartoma's CN2254NS, CN2303, CN2303, CN293, CN750, CN790, CN8008NS, CN8201NS, CN983NS, and CN996NS.

[0089] In this application, the nano-hybrid modified acrylate prepolymer includes at least one of inorganic particle hybrid modified acrylate prepolymer and organosilicon hybrid modified acrylate prepolymer.

[0090] In this application, the inorganic particles include at least one of silicon dioxide and titanium dioxide.

[0091] In this application, the organosilicon includes polydimethylsiloxane.

[0092] In this application, the nano-hybrid modified acrylate prepolymer can be purchased commercially. For example, the nano-hybrid modified acrylate prepolymer includes, but is not limited to, one or more of Haohui New Materials CR91000, CR91093, CR90223, HU280; and Lankelu L-6902X, L-6901, L-6902.

[0093] In this application, the inorganic nanoparticles include at least one of titanium oxide, zirconium oxide, and core-shell nanoparticles; the core layer of the core-shell nanoparticles includes titanium oxide, and the shell layer includes zirconium oxide.

[0094] In this application, the average particle size of the inorganic nanoparticles is 5~25nm, for example, it can be 6 nm, 8 nm, 10 nm, 12 nm, 14 nm, 16 nm, 18 nm, 20 nm, 22 nm, 24 nm, etc.

[0095] In this application, the inorganic nanoparticles can be obtained commercially, and exemplary include one or more of PixClearZirconia 10nm, PixClear Titania 20nm, PixCor®core-shell 20nm, etc.

[0096] In this application, the photoinitiators include 2-hydroxy-2-methyl-1-phenyl-1-propanone (photoinitiator 1173), diphenyl-(4-phenylthio)phenylsulfonium hexafluoroantimonate (photoinitiator 1176), 1-hydroxycyclohexylphenyl ketone (photoinitiator 184), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (photoinitiator TPO), ethyl 2,4,6-trimethylbenzoylphenylphosphonate (TPO-L), and 1,1'-(methylenedi- 4,1-Phenylidene)bis(2-hydroxy-2-methyl-1-propanone (photoinitiator 127), 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone (photoinitiator 369), 2-isopropylthioxanthone (ITX), benzoin diethyl ether (BDK), phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (photoinitiator 819), oxobis(ethane-2,1-diyl)bis(2-oxo-2-phenylacetic acid ester (photoinitiator 754), 2-chlorothioxanthone (photoinitiator 380), methyl benzoylformate (BMF), 9,10-dibutoxyanthracene (ANTHRACURE™ UVS-1331), 9,10-diethoxyanthracene (ANTHRACURE™ UVS-1101), bis(4-(diphenylsulfonium)phenyl)sulfide-bis(hexafluorophosphate) (Easepi) At least one of 6992), 4-isobutylphenyl-4'-methylphenyliodohexafluorophosphate (Easepi 250).

[0097] In this application, the coupling agent includes a silane coupling agent.

[0098] In this application, the coupling agent includes at least one of γ-(methacryloyloxy)propyltrimethoxysilane, vinyltrimethoxysilane, vinyltri(2-methoxyethoxy)silane, vinyltriethoxysilane, γ-(methacryloyloxy)propyltriethoxysilane, methacryloyloxymethyltriethoxysilane, 3-methacryloyloxypropyltri(methoxyethoxy)silane, methacryloyloxypropyltri(dimethylsiloxane)silane, γ-(acryloyloxy)propyltrimethoxysilane, γ-(acryloyloxy)propyltriethoxysilane, allyltri(trimethylsiloxy)silane, 1,3-bis(3-methacryloyloxypropyl)tetra(trimethylsiloxy)disiloxane, and N-(3-acryloyloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane.

[0099] In this application, the solvent includes at least one of propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, ethyl acetate, N,N-dimethylformamide, methyl ethyl ketone, dimethyl sulfoxide, and butyl acetate.

[0100] Secondly, this application provides a method for preparing the nanoimprint adhesive according to the first aspect, the preparation method comprising the following steps:

[0101] The nanoimprint adhesive is obtained by mixing a high refractive index monomer, an acrylate prepolymer, a nano-hybridized acrylate prepolymer, inorganic nanoparticles, a photoinitiator, a coupling agent, and a solvent.

[0102] In this application, the mixing method includes:

[0103] (1) The solvent, high refractive index monomer, acrylate prepolymer, and nano-hybrid modified acrylate prepolymer are mixed to obtain the first mixture;

[0104] (2) The first mixture is mixed with a coupling agent and a photoinitiator to obtain a second mixture;

[0105] (3) The second mixture is mixed and dispersed with inorganic nanoparticles, allowed to stand, and filtered to obtain the nanoimprint adhesive.

[0106] In this application, the mixing in step (1) is carried out in the presence of a protective atmosphere, which includes, but is not limited to, nitrogen; the mixing speed is 300~700 rpm, for example, 400 rpm, 500 rpm, 600 rpm, etc.; the mixing temperature is 21~25℃, for example, 22℃, 23℃, 24℃, etc.; and the time is 20~40 min, for example, 25 min, 30 min, 35 min, etc.

[0107] In this application, the mixing speed in step (2) is 600~1000 rpm, for example, 700 rpm, 800 rpm, 900 rpm, etc.; the temperature is 21~25℃, for example, 22℃, 23℃, 24℃, etc.; and the time is 20~40 min, for example, 25 min, 30 min, 35 min, etc.

[0108] In this application, the mixing and dispersion temperature in step (3) is 21~25℃, for example, 22℃, 23℃, 24℃, etc.; the time is 10~15h, for example, 11h, 12h, 13h, 14h, etc.

[0109] In this application, the settling time is 20-40 minutes, for example, 25 minutes, 30 minutes, 35 minutes, etc.; the filtration is performed using an organic filter membrane.

[0110] In this application, the nanoimprint adhesive described in the first aspect can be applied to pattern transfer.

[0111] The numerical range described in this application includes not only the point values ​​listed above, but also any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of brevity, this application will not exhaustively list the specific point values ​​included in the range.

[0112] Compared with the prior art, the beneficial effects of this application are as follows:

[0113] The nanoimprint adhesive provided in this application is formulated by compounding a refractive index monomer with a specific structure, an acrylate prepolymer, a nano-hybridized acrylate prepolymer, and inorganic nanoparticles in a specific amount. The resulting nanoimprint adhesive has a high refractive index, excellent mechanical strength, excellent high temperature resistance, and good flowability. When used in nanoimprint technology, the resulting products have a high appearance yield and good performance, which can meet the requirements of various nanoimprint processes and can achieve large-scale mass production. Detailed Implementation

[0114] The technical solution of this application will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely to help understand this application and should not be regarded as specific limitations on this application.

[0115] All materials used in this application are commercially available or prepared using conventional methods. Unless otherwise specified, the materials used in this application are as follows.

[0116] 1,4-Dithiohexacyclic-2,5-dithiol was prepared in-house, and the synthetic route is as follows.

[0117] .

[0118] The specific preparation method includes the following steps:

[0119] (S1) Under an argon (Ar) atmosphere, 1,4-dithiohexane-2,5-diol (10.4 g, 68.4 mmol) was stirred and dispersed in anhydrous pyridine (22 mL); the system temperature was lowered to 0 °C, and acetic anhydride (15 mL, 157 mmol) was slowly added dropwise using a dropping funnel. During stirring, the product precipitated as a white precipitate, which was the crude product. The crude product was washed with water and then recrystallized from methanol to obtain 1,4-dithiohexane-2,5-diol acetate.

[0120] (S2) Under an Ar atmosphere, 1,4-dithiohexacyclo-2,5-diol acetate (4.16 g, 17.6 mmol) was dissolved in 40 mL of anhydrous dichloromethane. The system was then cooled to 0 °C and stirred for 10 minutes until homogeneous. Thioacetic acid (3.6 g, 47.5 mmol) was added, and the mixture was stirred again for 10 minutes until homogeneous. Then, 0.30 mL of boron trifluoride diethyl ether complex (BF3-Et2O) was added dropwise as a catalyst. The system was reacted sequentially at -7 °C for 2 h, at 0 °C for 2 h, and finally stirred at room temperature for 5 h. The reaction was then quenched with 10% potassium carbonate (K2CO3) solution, and the organic layer was washed with water. The resulting organic layer was dehydrated with anhydrous MgSO4, filtered, and the solvent was removed by rotary evaporation to obtain the crude product. The crude product was recrystallized from methanol to obtain 1,4-dithiohexacyclo-2,5-dithiol acetate.

[0121] (S3) Under an Ar atmosphere, 6.8 g (81 mmol) of 1,4-dithiohexane-2,5-dithiol acetate was dissolved in chloroform (50.0 mL), and 32 mL of a mixture of HCl and methanol was added at a volume ratio of 1:15. The mixture was then heated at 60 °C for 16 h. The solution was cooled to room temperature and concentrated to approximately 15 mL. The solution was purified by column chromatography to obtain a colorless viscous liquid, which was then dehydrated in a vacuum drying oven to obtain 1,4-dithiohexane-2,5-dithiol.

[0122] Preparation Example 1

[0123] This preparation example provides a high-refractive-index monomer, the structure of which is as follows: (Compound P1); The synthetic route for the high refractive index monomer is as follows;

[0124] .

[0125] The specific preparation method includes the following steps:

[0126] (1) Synthesis of 1-(2-thiophene thioether)-3-chloro-2-propanol

[0127] 100 mmol of 2-mercaptothiophene was mixed with 12 mL of DBU (80 mmol) in 150 mL of toluene and added to a 250 mL round-bottom flask equipped with a magnetic stir bar. The mixture was stirred for 30 minutes. Subsequently, 8.6 mL of epichlorohydrin (110 mmol) was slowly added dropwise. The reaction vessel was stirred at room temperature for 16 hours. Afterward, volatiles were removed under reduced pressure, and the residue was diluted with dichloromethane (DCM) and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL) to obtain a mixed organic extract. The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using a mixture of 20% ethyl acetate (EtOAc) in hexane as the eluent, ultimately yielding a colorless, low-viscosity liquid.

[0128] (2) Synthesis of (1-(2-thiophene sulfide)-2-propanol)-1,4-dithiohexacyclic-2,5-disulfide

[0129] 50 mmol of 1,4-dithiohexane-2,5-dithiol was mixed with 8 mL of DBU (53.5 mmol) in 100 mL of toluene and added to a 250 mL round-bottom flask equipped with a magnetic stir bar. The mixture was stirred for 30 minutes. Subsequently, 110 mmol of 1-(2-thiophene sulfide)-3-chloro-2-propanol (110 mmol) was slowly added dropwise. The reaction vessel was stirred at room temperature for 20 hours. Afterward, volatiles were removed under reduced pressure, and the residue was diluted with DCM and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using a mixture of 20% ethyl acetate (EtOAc) in hexane as eluent, yielding a pale yellow viscous liquid.

[0130] (3) Synthesis of (1-(2-thiophene sulfide)-2-propylacrylate)-1,4-dithiohexacyclic-2,5-disulfide

[0131] (1-(2-thiophene sulfide)-2-propanol)-1,4-dithiohexacyclic-2,5-disulfide (35 mmol), 24.3 mL of triethylamine (175 mmol), and 0.4 g of butylated hydroxytoluene (BHT) (1.75 mmol) were added to a 250 mL round-bottom flask equipped with a magnetic stir bar, diluted with 120 mL of dichloromethane, and stirred for 30 minutes under argon protection. After cooling the solution to 0 °C, 6.3 mL of acryloyl chloride (77 mmol) was added dropwise under argon protection, followed by 0.4 g of 4-dimethylaminopyridine (DMAP) (3.5 mmol). The reaction mixture was stirred at room temperature for 20 hours. Volatile substances were then removed under reduced pressure. The residue was diluted with 250 mL of dichloromethane and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL) to obtain a mixed organic extract. The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using hexane containing 20% ​​ethyl acetate as the eluent, ultimately yielding the target compound as a colorless to slightly yellow viscous liquid, which is the high-refractive-index monomer.

[0132] Preparation Example 2

[0133] This preparation example provides a high-refractive-index monomer, the structure of which is as follows: (Compound P2); The synthetic route for the high refractive index monomer is as follows;

[0134] .

[0135] The specific preparation method includes the following steps:

[0136] (1) Synthesis of 1-benzylthiol-3-chloro-2-propanol

[0137] Thiophenol (100 mmol) was mixed with 12 mL of DBU (80 mmol) in 150 mL of toluene and added to a 250 mL round-bottom flask equipped with a magnetic stir bar. The mixture was stirred for 30 minutes. Subsequently, 8.6 mL of epichlorohydrin (110 mmol) was slowly added dropwise. The reaction vessel was stirred at room temperature for 16 hours. Afterward, volatiles were removed under reduced pressure, and the residue was diluted with DCM and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using a mixture of 20% ethyl acetate (EtOAc) in hexane as eluent, yielding a colorless, low-viscosity liquid.

[0138] (2) Synthesis of (1-phenylsulfide-2-propanol)-1,4-dithiohexacyclic-2,5-disulfide

[0139] 50 mmol of 1,4-dithiohexane-2,5-dithiol was mixed with 8 mL of DBU (53.5 mmol) in 100 mL of toluene and added to a 250 mL round-bottom flask equipped with a magnetic stir bar. The mixture was stirred for 30 minutes. Subsequently, 110 mmol of 1-phenylthiol-3-chloro-2-propanol (110 mmol) was slowly added dropwise. The reaction vessel was stirred at room temperature for 20 hours. Afterward, volatiles were removed under reduced pressure, and the residue was diluted with DCM and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using a mixture of 20% ethyl acetate (EtOAc) in hexane as eluent, yielding a pale yellow viscous liquid.

[0140] (3) Synthesis of (1-phenyl sulfide-2-propyl acrylate)-1,4-dithiohexacyclic-2,5-disulfide

[0141] (1-phenylsulfide-2-propanol)-1,4-dithiohexacyclic-2,5-disulfide (35 mmol), 24.3 mL of triethylamine (175 mmol), and 0.4 g of butylated hydroxytoluene (BHT) (1.75 mmol) were added to a 250 mL round-bottom flask equipped with a magnetic stir bar. The solution was diluted with 120 mL of dichloromethane and stirred for 30 minutes under argon protection. After cooling the solution to 0 °C, 6.3 mL of acryloyl chloride (77 mmol) was added dropwise under argon protection, followed by 0.4 g of 4-dimethylaminopyridine (DMAP) (3.5 mmol). The reaction mixture was stirred at room temperature for 20 hours. Volatile substances were then removed under reduced pressure. The residue was diluted with 250 mL of dichloromethane and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using 20% ​​ethyl acetate (hexane) as eluent to finally obtain the target compound as a colorless to slightly yellow viscous liquid, which is the high refractive index monomer.

[0142] Preparation Example 3

[0143] This preparation example provides a high-refractive-index monomer, the structure of which is as follows: (P3 compound); the synthetic route of the high refractive index monomer is as follows;

[0144] .

[0145] The specific preparation method includes the following steps:

[0146] (1) Synthesis of 1-(4-methylthiophenylthiol)-3-chloro-2-propanol

[0147] 100 mmol of 4-methylthiophenethiophenol was mixed with 12 mL of DBU (80 mmol) in 150 mL of toluene and added to a 250 mL round-bottom flask equipped with a magnetic stir bar. The mixture was stirred for 30 minutes. Subsequently, 8.6 mL of epichlorohydrin (110 mmol) was slowly added dropwise. The reaction vessel was stirred at room temperature for 16 hours. Afterward, volatiles were removed under reduced pressure, and the residue was diluted with DCM and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using a mixture of 20% ethyl acetate (EtOAc) in hexane as eluent, yielding a colorless, low-viscosity liquid.

[0148] (2) Synthesis of (1-(4-methylthiophenylthiol)-2-propanol)-1,4-dithiohexacyclic-2,5-disulfide

[0149] 50 mmol of 1,4-dithiohexane-2,5-dithiol was mixed with 8 mL of DBU (53.5 mmol) in 100 mL of toluene and added to a 250 mL round-bottom flask equipped with a magnetic stir bar. The mixture was stirred for 30 minutes. Subsequently, 110 mmol of 1-(4-methylthiophenylthiol)-3-chloro-2-propanol was slowly added dropwise. The reaction vessel was stirred at room temperature for 20 hours. Afterward, volatiles were removed under reduced pressure, and the residue was diluted with DCM and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using a mixture of 20% ethyl acetate (EtOAc) in hexane as eluent, yielding a pale yellow viscous liquid.

[0150] (3) Synthesis of (1-(4-methylthiophenylthiol)-2-propylacrylate)-1,4-dithiohexacyclic-2,5-disulfide

[0151] (1-(4-methylthiobenzylthiol)-2-propanol)-1,4-dithiohexacyclic-2,5-disulfide (35 mmol), 24.3 mL of triethylamine (175 mmol), and 0.4 g of butylated hydroxytoluene (BHT) (1.75 mmol) were added to a 250 mL round-bottom flask equipped with a magnetic stir bar, diluted with 120 mL of dichloromethane, and stirred for 30 minutes under argon protection. After cooling the solution to 0 °C, 6.3 mL of acryloyl chloride (77 mmol) was added dropwise under argon protection, followed by 0.4 g of 4-dimethylaminopyridine (DMAP) (3.5 mmol). The reaction mixture was stirred at room temperature for 20 hours. Volatile substances were then removed under reduced pressure. The residue was diluted with 250 mL of dichloromethane and washed successively with 1 mol / L hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using 20% ​​ethyl acetate (hexane) as eluent to finally obtain the target compound as a colorless to slightly yellow viscous liquid, which is the high refractive index monomer.

[0152] Preparation Example 4

[0153] This preparation example provides a high-refractive-index monomer, the structure of which is as follows: (Compound P4); The synthetic route for the high refractive index monomer is as follows;

[0154] .

[0155] The specific preparation method includes the following steps:

[0156] (1) Synthesis of 1-(2-naphthylthion)-3-chloro-2-propanol

[0157] 100 mmol of 2-mercaptonaphthalene was mixed with 12 mL of DBU (80 mmol) in 150 mL of toluene and added to a 250 mL round-bottom flask equipped with a magnetic stir bar. The mixture was stirred for 30 minutes. Subsequently, 8.6 mL of epichlorohydrin (110 mmol) was slowly added dropwise. The reaction vessel was stirred at room temperature for 16 hours. Afterward, volatiles were removed under reduced pressure, and the residue was diluted with DCM and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using a mixture of 20% ethyl acetate (EtOAc) in hexane as eluent, yielding a colorless, low-viscosity liquid.

[0158] (2) Synthesis of (1-(2-naphthylthion)-2-propanol)-1,4-dithiohexacyclic-2,5-disulfide

[0159] 50 mmol of 1,4-dithiohexane-2,5-dithiol was mixed with 8 mL of DBU (53.5 mmol) in 100 mL of toluene and added to a 250 mL round-bottom flask equipped with a magnetic stir bar. The mixture was stirred for 30 minutes. Subsequently, 110 mmol of 1-(2-naphthylthion)-3-chloro-2-propanol (110 mmol) was slowly added dropwise. The reaction vessel was stirred at room temperature for 20 hours. Afterward, volatiles were removed under reduced pressure, and the residue was diluted with DCM and washed successively with 1 M hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using a mixture of 20% ethyl acetate (EtOAc) in hexane as eluent, yielding a pale yellow viscous liquid.

[0160] (3) Synthesis of (1-(2-naphthalenesulfide)-2-propylacrylate)-1,4-dithiohexacyclic-2,5-disulfide

[0161] (1-(2-naphthylthione)-2-propanol)-1,4-dithiohexacyclic-2,5-disulfide (35 mmol), 24.3 mL of triethylamine (175 mmol), and 0.4 g of butylated hydroxytoluene (BHT) (1.75 mmol) were added to a 250 mL round-bottom flask equipped with a magnetic stir bar, diluted with 120 mL of dichloromethane, and stirred for 30 min under argon protection. After cooling the solution to 0 °C, 6.3 mL of acryloyl chloride (77 mmol) was added dropwise under argon protection, followed by 0.4 g of 4-dimethylaminopyridine (DMAP) (3.5 mmol). The reaction mixture was stirred at room temperature for 20 h. Volatile substances were then removed under reduced pressure, and the residue was diluted with 250 mL of dichloromethane and washed successively with 1 mol / L hydrochloric acid (100 mL), distilled water (100 mL), and brine (50 mL). The mixed organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using 20% ​​ethyl acetate (hexane) as eluent to finally obtain the target compound as a colorless to slightly yellow viscous liquid, which is the high refractive index monomer.

[0162] The test results of the high refractive index monomers provided in Examples 1-4 of this application are shown in Table 1.

[0163] Table 1

[0164]

[0165] The test methods for the relevant test items in Table 1 are as follows:

[0166] (1) Appearance: Obtained through visual inspection;

[0167] (2) Viscosity at 25°C: The viscosity of the high refractive index monomer at 25°C was tested on a Brookfield rheometer;

[0168] (3) Refractive index: The refractive index was measured using an ellipsometer;

[0169] (4) Tg: The differential scanning calorimeter was used for testing.

[0170] Example 1

[0171] The nanoimprint adhesive provided in this embodiment comprises, by weight percentage, 40% propylene glycol methyl ether acetate, 15% high refractive index monomer (provided in Preparation Example 1), 8% acrylate prepolymer (HR6200), 8% nano-hybrid modified acrylate prepolymer (CR91000), 1% γ-(methacryloyloxy)propyltrimethoxysilane, 3% photoinitiator TPO, and 25% zirconium oxide nanoparticles (PixClear Zirconia 10nm nanoparticle dispersion, with a solid content of 65%).

[0172] This embodiment also provides a method for preparing the nanoimprint adhesive, specifically including the following steps:

[0173] (1) Add 40g of propylene glycol methyl ether acetate (PGMEA) to a container, purge with nitrogen and start stirring at 500rpm. Then slowly add 15g of the high refractive index monomer provided in Preparation Example 1, 8g of HR6200 acrylate prepolymer and 8g of CR91000 nano-hybrid modified acrylate prepolymer. Stir for 30min to completely disperse and dissolve the system to obtain a uniform solution. Maintain the liquid temperature in the container at 23±2℃ during the process.

[0174] (2) Adjust the rotation speed to 800 rpm, and under the illumination of yellow light, slowly add 1g of γ-(methacryloyloxy)propyltrimethoxysilane coupling agent and 3g of TPO photoinitiator, and continue stirring for 30 min to completely disperse and dissolve the system to obtain a uniform solution. During the process, maintain the liquid temperature in the container at 23±2℃.

[0175] (3) Slowly add 25g of PixClear Zirconia 10nm nanoparticle dispersion and continue stirring for 12h, maintaining the liquid temperature in the container at 23±2℃ during the process.

[0176] (4) After stirring, let stand for 30 minutes, then filter and encapsulate with a 0.22μm organic filter membrane under pressure to obtain a semi-transparent to slightly transparent nanoimprint adhesive, which is the nanoimprint adhesive.

[0177] Example 2

[0178] The nanoimprint adhesive provided in this embodiment differs from that in Example 1 in that the high refractive index monomer is provided in Preparation Example 2, while the other components, amounts, and preparation methods are the same as in Example 1.

[0179] Example 3

[0180] The nanoimprint adhesive provided in this embodiment differs from that in Example 1 in that the high refractive index monomer is provided by Preparation Example 3, while the other components, amounts, and preparation methods are the same as in Example 1.

[0181] Example 4

[0182] The nanoimprint adhesive provided in this embodiment differs from that in Example 1 in that the high refractive index monomer is provided by Preparation Example 4, while the other components, amounts, and preparation methods are the same as in Example 1.

[0183] Example 5

[0184] The nanoimprint adhesive provided in this embodiment comprises, by weight percentage: 36% propylene glycol methyl ether acetate, 12% high refractive index monomer (provided in Preparation Example 1), 10% acrylate prepolymer (DR-U384), 5% nano-hybrid modified acrylate prepolymer (CR90223), 3% vinyltris(2-methoxyethoxy)silane, 4% photoinitiator 1176, and 30% titanium dioxide nanoparticles (PixClear Titania 20nm nanoparticle dispersion, with a solid content of 60%).

[0185] This embodiment also provides a method for preparing the nanoimprint adhesive, the specific steps of which are the same as in Example 1.

[0186] Example 6

[0187] This embodiment provides a nanoimprint adhesive, which, by weight percentage, comprises 22% propylene glycol methyl ether acetate, 18% high refractive index monomer (provided in Preparation Example 1), 5% acrylate prepolymer (DR-U384), 10% nano-hybrid modified acrylate prepolymer (Lankel L-6902X), 5% methacryloyloxymethyltriethoxysilane, 5% photoinitiator 184, and 35% core-shell nanoparticles (PixCor® core-shell 20nm nanoparticle dispersion, with a solid content of 60%).

[0188] This embodiment also provides a method for preparing the nanoimprint adhesive, the specific steps of which are the same as in Example 1.

[0189] Comparative Example 1

[0190] The nanoimprint adhesive provided in this comparative example differs from that in Example 1 in that the high refractive index monomer is replaced with an equal mass of 4,4'-dimercaptodiphenyl sulfide dimethyl methacrylate, while the other components, amounts, and preparation methods are the same as in Example 1.

[0191] Comparative Example 2

[0192] The nanoimprinting adhesive provided in this comparative example differs from that in Example 1 in that the mass content of the high refractive index monomer is 5%, and the amount of solvent is adjusted to make the total amount 100%. Other components, amounts, and preparation methods are the same as in Example 1.

[0193] Comparative Example 3

[0194] The nanoimprinting adhesive provided in this comparative example differs from that in Example 1 in that the mass content of the high refractive index monomer is 24%, and the amount of solvent is adjusted to make the total amount 100%. Other components, amounts, and preparation methods are the same as in Example 1.

[0195] Comparative Example 4

[0196] The nanoimprinting adhesive provided in this comparative example differs from that in Example 1 in that the mass content of the acrylate prepolymer is 14%, the mass content of the nano-hybrid modified acrylate prepolymer is 2%, and the other components, amounts, and preparation methods are the same as in Example 1.

[0197] Comparative Example 5

[0198] The nanoimprinting adhesive provided in this comparative example differs from that in Example 1 in that the mass content of the acrylate prepolymer is 2%, the mass content of the nano-hybrid modified acrylate prepolymer is 14%, and the other components, amounts, and preparation methods are the same as in Example 1.

[0199] Comparative Example 6

[0200] The nanoimprinting adhesive provided in this comparative example differs from that in Example 1 in that the mass content of the acrylate prepolymer is 16%, and there is no nano-hybrid modified acrylate prepolymer. The other components, amounts, and preparation methods are the same as in Example 1.

[0201] The nanoimprint embossing adhesives provided in the examples and comparative examples were spin-coated onto 4-inch glass wafers and cured under oxygen-free conditions to obtain a 2 μm imprint embossing adhesive layer. The performance parameters of the imprint embossing adhesive and the cured film are shown in Tables 2 and 3.

[0202] Table 2

[0203]

[0204] Table 3

[0205]

[0206] The test methods for the relevant test items in Tables 2 and 3 are as follows:

[0207] 1. Appearance

[0208] Pour the nanoimprinting adhesive into a colorless, transparent glass bottle and visually observe its appearance under white light or natural light.

[0209] 2. Viscosity test

[0210] The viscosity of the nanoimprint adhesive at 20°C was tested using a Brookfield rheometer.

[0211] 3. Solid content test

[0212] The nanoimprint adhesive was weighed on an analytical balance, then baked in a forced-air drying oven at 120°C for 2 hours. The weight of the baked adhesive was then weighed again to calculate its solid content.

[0213] 4. Hardness test

[0214] Nanoimprint adhesive was spin-coated onto a silicon wafer, baked at 80°C for 5 minutes, and then exposed and imprinted on an imprinting device to form a uniform film layer with a thickness of 2μm. Its hardness was tested using a nanoindenter.

[0215] 5. Young's modulus test

[0216] Nanoimprint adhesive was spin-coated onto a silicon wafer, baked at 80°C for 5 minutes, and then exposed and imprinted on an imprinting device to form a uniform film layer with a thickness of 2μm. Its Young's modulus was tested using a nanoindenter.

[0217] 6. Surface water droplet angle test

[0218] Nanoimprint adhesive was spin-coated onto a silicon wafer, baked at 80°C for 5 minutes, and then exposed and imprinted on an imprinting device to form a uniform film layer with a thickness of 2μm. The surface water droplet angle was measured using a water droplet angle meter.

[0219] 7. Refractive index test

[0220] Nanoimprint adhesive was spin-coated onto a silicon wafer, baked at 80°C for 5 minutes, and then exposed and imprinted on an imprinting device to form a uniform film layer with a thickness of 2μm. Its refractive index was measured using an ellipsometer.

[0221] As shown in Tables 2 and 3, the nanoimprint adhesive provided in this application has a hardness ≥66D, a Young's modulus ≥1.8GPa, a surface water droplet angle of 72~78°, and a refractive index of 1.71~1.74 after curing.

[0222] The applicant declares that the above description is only a specific implementation of this application, but the protection scope of this application is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application fall within the protection and disclosure scope of this application.

Claims

1. A nanoimprinting adhesive, characterized in that, The nanoimprint adhesive comprises, by weight percentage, 10-20% high refractive index monomer, 5-10% acrylate prepolymer, 5-10% nano-hybrid modified acrylate prepolymer, 20-35% inorganic nanoparticles, 3-5% photoinitiator, 1-5% coupling agent and 15-55% solvent. The high-refractive-index monomer has the structure shown in Formula I; Equation I; In Formula I, R1 and R2 are each independently selected from any one of substituted or unsubstituted C6~C30 aryl, substituted or unsubstituted C3~C30 heteroaryl, substituted or unsubstituted C6~C30 arylthio, and substituted or unsubstituted C3~C30 heteroarylthio. R3, R4, R5, R6, R7, and R8 are each independently selected from H and any one of the C1-C10 straight-chain or branched alkyl groups, whether substituted or unsubstituted. n1 and n2 are each independently selected from integers ≥ 1; The substituents include at least one of hydroxyl, amino, C1-C6 straight-chain or branched alkyl, C6-C20 aryl, and C3-C20 heteroaryl.

2. The nanoimprint adhesive according to claim 1, characterized in that, R1 and R2 are each independently selected from any one of the following groups, or any one of the following groups substituted by a substituent; Wherein, R is selected from C1~C6 straight-chain or branched alkyl groups; The substituents include at least one of hydroxyl, amino, C1-C6 straight-chain or branched alkyl, C6-C20 aryl, and C3-C20 heteroaryl. " "" indicates a connection point.

3. The nanoimprint adhesive according to claim 1, characterized in that, R3, R4, R5, R6, R7, and R8 are each independently selected from H or methyl; The values ​​of n1 and n2 are each 1 independently.

4. The nanoimprint adhesive according to claim 1, characterized in that, The high refractive index monomer includes at least one of the following compounds; 、 、 、 。 5. The nanoimprint adhesive according to claim 1, characterized in that, The high-refractive-index monomer has a refractive index ≥ 1.6; The glass transition temperature of the high refractive index monomer is ≥100℃.

6. The nanoimprint adhesive according to claim 1, characterized in that, The high refractive index monomer is prepared by the following method, the method comprising: (1) Compound A reacts with compound B to give the first product; (2) The first product was reacted with 1,4-dithiohexacyclo-2,5-dithiol to obtain the second product; (3) The second product is reacted with compound D to obtain the high refractive index monomer; The compound A has the structure shown in formula A: R-SH formula A; The compound B has the structure shown in formula B: Formula B; The compound D has the structure shown in formula D: Formula D; In formula A, R is selected from the same range as R1 or R2 in formula I; In formula B, n is selected from integers ≥ 1; In formula B or formula D, X is selected from halogens; In formula D, , , Each is independently selected from the same range of constraints as R3, R4, R5, R6, R7, or R8 in Equation I; The 1,4-dithiohexacyclic-2,5-dithiol is prepared by the following method, the method comprising: (S1) 1,4-Dithiohexacyclo-2,5-diol reacts with compound E to give a third product; (S2) The third product is reacted with compound F to give the fourth product; (S3) The fourth product is subjected to a hydrolysis reaction to obtain the 1,4-dithiohexacyclo-2,5-dithiol; The compound E has the structure shown in formula E: Formula E; The compound F has the structure shown in formula F: Formula F; In formula E or formula F, Selected from C1~C10 straight-chain or branched alkyl groups.

7. The nanoimprint adhesive according to claim 1, characterized in that, The acrylate prepolymer includes at least one of polyurethane acrylate prepolymer, polyester acrylate prepolymer, and epoxy acrylate prepolymer.

8. The nanoimprint adhesive according to claim 1, characterized in that, The nano-hybrid modified acrylate prepolymer includes at least one of inorganic particle hybrid modified acrylate prepolymer and organosilicon hybrid modified acrylate prepolymer; The inorganic particles include at least one of silicon dioxide and titanium dioxide; The organosilicon includes polydimethylsiloxane.

9. The nanoimprint adhesive according to claim 1, characterized in that, The inorganic nanoparticles include at least one of titanium oxide, zirconium oxide, and core-shell nanoparticles; the core layer of the core-shell nanoparticles includes titanium oxide, and the shell layer includes zirconium oxide. The inorganic nanoparticles have an average particle size of 5-25 nm.

10. The nanoimprint adhesive according to claim 1, characterized in that, The photoinitiator includes 2-hydroxy-2-methyl-1-phenyl-1-propanone, diphenyl-(4-phenylthio)phenylsulfonium hexafluoroantimonate, 1-hydroxycyclohexylphenyl ketone, and 2,4,6-hydroxyphenylacetone. At least one of the following: -trimethylbenzoyl-diphenylphosphine oxide, ethyl 2,4,6-trimethylbenzoylphenylphosphine, 1,1'-(methylenedi-4,1-phenylene)bis(2-hydroxy-2-methyl-1-propanone, 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 2-isopropylthioxanthone, benzoin diethyl ether, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, oxobis(ethane-2,1-diyl)bis(2-oxo-2-phenylacetic acid ester, 2-chlorothioxanthone, methyl benzoylformate, 9,10-dibutoxyanthracene, 9,10-diethoxyanthracene, bis(4-(diphenylsulfonium)phenyl)sulfide-bis(hexafluorophosphate), 4-isobutylphenyl-4'-methylphenyliodohexafluorophosphate; The coupling agent includes a silane coupling agent; The solvent includes at least one of propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, ethyl acetate, N,N-dimethylformamide, methyl ethyl ketone, dimethyl sulfoxide, and butyl acetate.

11. A method for preparing a nanoimprint adhesive according to any one of claims 1 to 10, characterized in that, The preparation method includes the following steps: The nanoimprint adhesive is obtained by mixing a high refractive index monomer, an acrylate prepolymer, a nano-hybridized acrylate prepolymer, inorganic nanoparticles, a photoinitiator, a coupling agent, and a solvent.

12. The preparation method according to claim 11, characterized in that, The mixing method includes: (1) The solvent, high refractive index monomer, acrylate prepolymer, and nano-hybrid modified acrylate prepolymer are mixed to obtain the first mixture; (2) The first mixture is mixed with a coupling agent and a photoinitiator to obtain a second mixture; (3) The second mixture is mixed and dispersed with inorganic nanoparticles, allowed to stand, and filtered to obtain the nanoimprint adhesive; The mixing in step (1) is carried out in the presence of a protective atmosphere, the mixing speed is 300~700 rpm, the temperature is 21~25℃, and the time is 20~40 min; The mixing speed in step (2) is 600~1000 rpm, the temperature is 21~25℃, and the time is 20~40 min; The mixing and dispersion in step (3) is carried out at a temperature of 21~25℃ for 10~15h.

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