Optical monomers of high refractive index and process for their preparation, resin mixtures and their use

Abstract

The application discloses a high-refractive optical monomer, a preparation method thereof, a resin mixture and application of the high-refractive optical monomer, wherein the high-refractive optical monomer comprises at least one group of hybrid units and two polysulfur chains respectively located at two ends of the hybrid units; the hybrid unit comprises three benzene sulfide rings connected by sulfur, and each benzene sulfide ring comprises a benzene ring and two cyclohexanedithioalkyl groups which are connected to the benzene ring in a hybrid mode. The high-refractive optical monomer has the advantages that the hybrid unit is rich in sulfur elements, benzene ring structures and benzene sulfide ring structures, the structures have high molar refractivity, the overall molecule has high refractivity, the benzene ring has certain rigidity and stability, and the heat resistance of the molecule is improved. The polysulfur chain increases the chain length of the whole molecule and improves the flexibility. The polysulfur chain is rich in sulfur elements, and the polysulfur chain and the hybrid unit interact, which is helpful to the penetration of visible light. The optical monomer has high visible light penetration, high refractivity and good heat resistance.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical materials, in particular to an optical monomer with high refractive index and a preparation method thereof, a resin mixture and application thereof. BACKGROUND

[0002] High-performance optical devices are increasingly developing towards light weight, miniaturization and integration. By nanoimprint technology, the designed pattern is transferred to the optical resin with high refractive index to meet the needs of light weight, miniaturization and integration. The refractive index of the resin currently sold in the domestic market is less than 1.65, which brings great limitations to the application of the material, and cannot realize nanoimprint or has poor light transmittance after nanoimprint. SUMMARY

[0003] Therefore, the present application provides an optical monomer with high refractive index and a preparation method thereof, a resin mixture and application thereof, aiming to realize high refractive index and high light transmittance of the optical monomer.

[0004] The optical monomer with high refractive index provided in the first aspect of the present application comprises at least one hybrid unit and two polysulfide chains respectively located at both ends of the hybrid unit; the hybrid unit comprises three benzothiophene rings connected by sulfur, and each benzothiophene ring comprises a benzene ring and two cyclohexanedithioalkyl groups connected to the benzene ring in a hybrid manner.

[0005] The optical monomer with high refractive index provided in the first aspect of the present application is rich in sulfur elements, benzene ring structures and benzothiophene ring structures in the hybrid unit. These structures themselves have high molar refractivity, so that the overall molecule has high refractive index. The benzene ring itself has a certain rigidity and a relatively stable structure, which can improve the heat resistance of the molecule. The polysulfide chain can increase the chain length of the whole molecule and improve the flexibility of the whole molecule. The polysulfide chain itself is rich in sulfur elements with high molar refractivity, and the polysulfide chain and the hybrid unit together are beneficial to separate the chromophore and disturb the interaction of intramolecular conjugation, which is helpful to the penetration of visible light. Therefore, the optical monomer of the present application has high visible light transmittance, and itself has high refractive index and good heat resistance.

[0006] In some embodiments, the polysulfide chain comprises at least three connected sulfurs; and / or the polysulfide chain is connected with an unsaturated functional group.

[0007] In some embodiments, the optical monomer has the following structural general formula (I):

[0008]

[0009] wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R12 Each is either H or substituted / unsubstituted C. 1-20 Alkylene, substituted or unsubstituted C 1-30 alkylene ether group, substituted or unsubstituted C 6-30 aryl and substituted or unsubstituted C 7-30 One of arylalkylene and fluoroalkyl; R 13 R 14 Each of them is either H or methyl; n1, n2, and n3 are positive integers from 1 to 50.

[0010] In some embodiments, n1, n2, and n3 are each 1, and R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 R 12 They are H and R respectively. 13 R 14 Each is either H or methyl;

[0011] The structural formula of the optical unit is as follows (A-1) or (A-2):

[0012]

[0013] In some embodiments, n1, n2, and n3 are each 1, and R1, R3, R5, R7, R9, and R 11 Each of them is a phenyl group, R2, R4, R6, R8, and R... 10 R 12 They are respectively H; R 13 R 14 Each is either H or methyl;

[0014] The structural formula of the optical unit is as follows (A-3) or (A-4):

[0015]

[0016] In some embodiments, n1, n2, and n3 are each 1, and R1, R3, R5, R7, R9, and R 11 Each of them is a methyl group, R2, R4, R6, R8, and R. 10 R 12 They are respectively H; R 13 R 14 Each is either H or methyl; the structural formula of the optical monomer is as follows (A-5) or (A-6):

[0017]

[0018] The resin mixture provided by the second aspect of the present application comprises the following components in percentage by weight: 10-79% of solvent; 10-79% of high refractive optical monomer of each of the foregoing embodiments; 10-50% of diluent; 0.1-10% of photoinitiator; 0.1-5% of leveling agent; and 0.1-5% of silane coupling agent.

[0019] The resin mixture provided by the second aspect of the present application has high refractive index and good light transmittance.

[0020] In some embodiments, the solvent is at least one of propylene glycol methyl ether acetate, ethyl acetate, dichloromethane, ethanol, isopropyl alcohol, butyl acetate, butyl acetate, tetrahydrofuran, dimethyl sulfoxide, N,N-dimethylformamide, tetramethyl ethylenediamine, carbon tetrachloride.

[0021] In some embodiments, the diluent is at least one of propylene glycol methyl ether acetate, EM2206, 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene.

[0022] In some embodiments, the absorption wavelength of the photoinitiator is 368-420 nm; and / or, the photoinitiator is at least one of acyloxyphosphine, thioxanthone and its derivatives, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxylic chloride, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxy-2-methyl ester, diethoxyphenylacetophenone, 4-tert-butyltrichloroacetophenone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2-dimethylaminoethylbenzoate, 4,6-trimethylbenzoyldimethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, benzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiethoxyphenylphosphine oxide, benzoyldiethoxyphosphine oxide, benzophenone and its derivatives, benzoin and its derivatives, anthraquinone and its derivatives, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, p-dimethylaminoethylbenzoate, diphenyl disulfide, camphorquinone, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxylic acid, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxy-2-bromoethyl ester, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropane-1-ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, alpha-aminoalkylphenone derivatives, phenyl-glyoxylic acid-methyl ester or oxy-phenyl-acetic acid 2-[2-oxy-2-phenyl-ethoxy-ethoxy]-ethyl ester and oxy-phenyl-acetic acid 2-[2-hydroxy-ethoxy]-ethyl ester.

[0023] In some embodiments, the flow leveling agent is one of BYK331, BYK370, BYK3505, and BYK348.

[0024] In some embodiments, the silane coupling agent is one of KH570, KH550, and KH560.

[0025] In some embodiments, the resin mixture has a refractive index greater than 1.73.

[0026] The resin mixture of the third aspect of the present application is used for nanoimprinting.

[0027] The resin mixture of the third aspect of the present application has good shape retention and high light transmittance when used for nanoimprinting.

[0028] The preparation method of the high-refractive optical monomer of the fourth aspect of the present application comprises at least the following steps: reacting a first monomer and a second monomer in the presence of ethanol and sodium ethoxide, extracting, removing solvent, and purifying to obtain a compound comprising a benzothiophene ring group as a first product; processing the first product to obtain a second product; reacting the second product with the first product in the presence of ethanol and sodium ethoxide to obtain a compound with a hybrid unit as a third product; reacting the third product with a third monomer to obtain a compound with a hybrid unit having multiple thiols at both ends of the chain as a fourth product; and reacting the fourth product with a fourth monomer to obtain a high-refractive optical monomer.

[0029] The preparation method of the high-refractive optical monomer of the fourth aspect of the present application can obtain an optical monomer with the desired structure through multiple steps of reaction, and the prepared optical monomer has high refractive index and heat resistance, and high visible light transmittance.

[0030] In some embodiments, the first monomer has the following structural formula: and / or,

[0031] The second monomer has the following structural formula: and / or,

[0032] The third monomer has the following structural formula: and / or,

[0033] The fourth monomer has the following structural formula:

[0034] In some embodiments, the processing of the first product to generate the second product comprises: stirring the first product in a toluene solution, a sodium hydrosulfide solution, and in the presence of tetrabutylammonium bromide at 100-110°C under reflux for 7-9 hours to generate the second product.

[0035] In some embodiments, the processing of the first product to generate the second product comprises: stirring the first product in a toluene solution, a sodium hydrosulfide solution, and in the presence of tetrabutylammonium bromide at 100-110°C under reflux for 7-9 hours to generate the second product. In some embodiments, the processing of the first product to generate the second product comprises: stirring the first product in a toluene solution, a sodium hydrosulfide solution, and in the presence of tetrabutylammonium bromide at 100-110°C under reflux for 7-9 hours to generate the second product. In some embodiments, the processing of the first product to generate the second product comprises: stirring the first product in a toluene solution, a sodium hydrosulfide solution, and in the presence of tetrabutylammonium bromide at 100-110°C under reflux for 7-9 hours to generate the second product.

[0036] In some embodiments, the processing of the first product to generate the second product comprises: stirring the first product in a toluene solution, a sodium hydrosulfide solution, and in the presence of tetrabutylammonium bromide at 100-110°C under reflux for 7-9 hours to generate the second product.

[0037] In some embodiments, the processing of the first product to generate the second product comprises: stirring the first product in a toluene solution, a sodium hydrosulfide solution, and in the presence of tetrabutylammonium bromide at 100-110°C under reflux for 7-9 hours to generate the second product.

[0038] It should be understood that the general description above and the detailed description below are merely exemplary and explanatory, and cannot limit the disclosure of the embodiments of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the following embodiment description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0040] Figure 1 is a general structural formula I of the high refractive optical monomer according to some embodiments of the present application;

[0041] Figure 2 is a high refractive optical monomer according to some embodiments of the present application, and the compound has a structural formula A-1;

[0042] Figure 3 is a high refractive optical monomer according to some embodiments of the present application, and the compound has a structural formula A-2;

[0043] Figure 4 is a high refractive optical monomer according to some embodiments of the present application, and the compound has a structural formula A-3;

[0044] Figure 5A-4 is a high refractive optical monomer of the present application, and its structural formula is shown in the following formula:

[0045] Figure 6 A-5 is a high refractive optical monomer of the present application, and its structural formula is shown in the following formula:

[0046] Figure 7 A-6 is a high refractive optical monomer of the present application, and its structural formula is shown in the following formula:

[0047] Figure 8 A-1 is a high refractive optical monomer of some embodiments of the present application, and its preparation method includes a multi-step reaction.

[0048] Figure 9 B-1 is a structural formula of an optical monomer in Comparative Example 1 of the present application.

[0049] Figure 10 A-1 is a high refractive optical monomer of some embodiments of the present application, and its preparation method includes a multi-step reaction.

[0050] Figure 11 B-2 is a structural formula of an optical monomer in Comparative Example 2 of the present application.

[0051] Figure 12 B-3 is a structural formula of an optical monomer in Comparative Example 3 of the present application.

[0052] Figure 13 A-1 is a high refractive optical monomer of some embodiments of the present application, and its preparation method includes a multi-step reaction. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, other embodiments obtained by those of ordinary skill in the art without creative work should fall within the protection scope of the present application.

[0054] It should also be understood that the terms used herein in the specification and the appended claims should not be construed as limiting the application to specific embodiments. Unless otherwise defined, all terms used in describing the application disclosed herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be apparent that the terms "comprises", "comprising", "includes", "including", "contains", "containing" or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises, includes, contains or contains elements or steps not recited in a claim should not be excluded or denied.

[0055] It should be further understood that the term "and / or" used in the description and claims of the application herein is used to mean any one and / or any combination of the associated listed items and includes all possible combinations thereof. The embodiments described below and in the examples are not mutually exclusive and can be combined with each other.

[0056] The existing commercially available resin has a refractive index less than 1.65, which cannot achieve nanoimprinting, or the light transmittance is poor after nanoimprinting, affecting the performance of the product.

[0057] In view of this, the embodiments of the present application propose a high-refractive optical monomer 100, as shown in the formula (I), which comprises at least one set of hybrid units and two polysulfide chains respectively located at both ends of the hybrid unit chain; the hybrid unit comprises three benzene sulfide rings connected by sulfur, and each benzene sulfide ring comprises a benzene ring and two cyclohexanedithioalkyl groups connected to the benzene ring in a hybrid manner. Figures 1 to 7

[0058] Therefore, the high-refractive optical monomer proposed in the present application is rich in sulfur elements and benzene sulfide ring structures in the hybrid unit. The S element slows down the propagation speed of light when passing through these materials due to its special electronic structure and atomic radius, thereby increasing the refractive index. The S element itself has the characteristics of high molar refractivity and low molecular dispersity, and can also provide certain chain flexibility, facilitating reaction with other functional groups and forming connections. The benzene sulfide ring itself has a relatively high refractive index, and has a conjugated structure in the benzene sulfide ring, which slows down the propagation speed of light when passing through, thereby increasing the refractive index. Therefore, the hybrid unit in the present application can make the overall molecule have a very high refractive index.

[0059] In addition, in the present application, the benzene ring and the cyclohexanedithioalkyl group are connected, which itself has a certain rigidity and a relatively stable structure, and can improve the heat resistance of the molecule.

[0060] The polysulfide chain of the present application can increase the chain length of the whole molecule, improve the flexibility of the whole molecule, and reduce birefringence and improve transparency by increasing chain flexibility. The polysulfide chain itself is rich in sulfur elements with high molar refractivity, and the polysulfide chain and the hybrid unit together are beneficial to the separation of chromophores and the disturbance of the interaction of intramolecular conjugation, thereby improving the refractive index of the whole molecule and facilitating the penetration of visible light; the longer polysulfide chain also has unique infrared transmission properties.

[0061] As can be seen from the above, the optical monomer of the present application has a high visible light transmittance, and itself has a high refractive index, good heat resistance.

[0062] It can be understood that, compared with the defects of the optical monomer used to prepare the resin in the prior art, which has a low refractive index and is not easy to penetrate visible light, the high-refractive optical monomer of the present application itself has a high refractive index, high light transmittance, and certain heat resistance. ​

[0063] In some embodiments, the polysulfur chain includes at least three sulfurs connected. Thus, the polysulfur chain can have a certain length and contain more S elements, which can improve the refractive index of the molecule while also improving the flexibility of the molecule. In some examples, the number of sulfurs in the polysulfur chain is an integer multiple of 3.

[0064] In some embodiments, the polysulfur chain is connected with an unsaturated functional group. The introduction of the unsaturated functional group allows the entire molecule to have a site that is easily activated at both ends. Under the action of a photoinitiator in a resin mixture, the unsaturated functional group can link individual molecules together to form a network structure.

[0065] Optionally, the unsaturated functional group can be in the form of C=C, C=O, etc. The cost of the reactants needs to be controlled within a reasonable range and the reaction needs to be easy to perform.

[0066] In some embodiments, as shown in Figure 1 the optical monomer has the following general structure (I):

[0067]

[0068] wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , and R 12 each is independently H or one of substituted or unsubstituted C 1-20 alkylene, substituted or unsubstituted C 1-30 alkylene ether group, substituted or unsubstituted C 6-30 arylene, and substituted or unsubstituted C 7-30 aralkylene, and fluoroalkyl; R 13 , and R 14 each is independently H or methyl; and n1, n2, and n3 are each a positive integer from 1 to 50.

[0069] For example, n1, n2, and n3 can each be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50.

[0070] When the above groups include long-chain alkane structures, the overall steric hindrance is small, and the chemical bonds can rotate freely. When subjected to external force impact, stress can be transferred, thereby making the molecule have good flexibility.

[0071] When the above group includes an alkylene ether group, the rotatability of the molecular chain can be improved, so that the flexibility of the whole molecule is better.

[0072] When the above group includes an arylene group, the hardness of the molecule is high.

[0073] When the above group includes an aralkylene group, then it has certain flexibility and hardness.

[0074] When the above group includes a fluorinated alkyl group, the lubricity of the molecule can be improved, the electronegativity of the fluorine atom is strong, and the atomic radius is small, when it replaces the hydrogen atom in the alkane, the electron cloud distribution of the carbon chain will change. This change makes the flexibility of the carbon chain decrease, and the molecular structure is more rigid and stable; in the lubrication process, the rigid molecular structure can better withstand the pressure and shear force, maintain the integrity of the lubricating film, and thus show good lubricity; at the same time, the introduction of fluorine atoms reduces the surface energy of the molecule, low surface energy makes fluorinated alkanes more easily spread on the friction interface to form a uniform lubricating film, reduce the direct contact between the friction surfaces, reduce the friction coefficient, and thus show lubricity.

[0075] It should be noted that R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 may be the same structure, or different structures.R 13 , R 14 may be the same structure, or different structures.

[0076] As can be seen from the above, the optical monomer of the application is roughly symmetrically arranged on the left and right sides of the hybrid unit as the center, so that more S elements are contained in the whole molecule. The molecular structure is rich in S elements and benzothiophene ring structures, etc. which have high molar refractivity, so that the whole molecule can realize high refractive index and high visible light transmittance.

[0077] In some embodiments, n1, n2, n3 are each 1, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 are each H, R 13 , R 14 are each H or methyl; as shown in formulas (A-1) or (A-2): Figure 2 and Figure 3

[0078]

[0079] In A-1, R 13 , R14 each independently H; in A-2, R 13 , R 14 each independently H.

[0080] In some embodiments, n1, n2, n3 are each 1, R1, R3, R5, R7, R9, R 11 each independently H; in A-2, R 10 , R 12 each independently H. 13 , R 14 each independently H or methyl; as shown in Figure 4 and Figure 5 The structure of the optical monomer is as follows (A-3) or (A-4):

[0081]

[0082] In A-3, R 13 , R 14 each independently H; in A-4, R 13 , R 14 each independently methyl.

[0083] In some embodiments, n1, n2, n3 are each 1, R1, R3, R5, R7, R9, R 11 each independently H; in A-2, R 10 , R 12 each independently H. 13 , R 14 each independently H or methyl; as shown in Figure 6 and Figure 7 The structure of the optical monomer is as follows (A-5) or (A-6):

[0084]

[0085] In A-5, R 13 , R 14 each independently H; in A-6, R 13 , R 14 each independently methyl.

[0086] In the above examples, compounds A-1, A-2, A-3, A-4, A-5 and A-6 all have three benzothiophene rings, and three sulfur and C=O, C=C are respectively connected on the benzene rings of the benzothiophene rings at both ends, so that the molecule is small and the material consumption is low, high refractive index and high light transmittance are achieved, and the end of the whole molecule has an active site.

[0087] Of course, in other embodiments, the high-refractive optical monomer can also be other structures, mainly containing the aforementioned hybrid unit, polysulfur chain, within the scope of the aforementioned general formula.

[0088] The present application provides a resin mixture, the resin mixture comprising the following components by weight percentage: 10-79% of solvent; 10-79% of the high-refractive optical monomer of the aforementioned embodiments; 10-50% of diluent; 0.1-10% of photoinitiator; 0.1-5% of leveling agent; 0.1-5% of silane coupling agent.

[0089] It can be understood that the present application uses a solvent with a weight percentage of 10-79% to make the components mixed uniformly, and less than the above range will make the components not mixed uniformly and the compatibility low; and more than the above range will make the effective components too few.

[0090] The present application uses an optical monomer with a weight percentage of 10-79% to make the resin mixture have high refractive index, high transmittance and thermal stability after curing, and less than the above range will make the refractive index of the mixture after curing insufficient and the consumables increase; and more than the above range will be not conducive to film formation.

[0091] The present application uses a diluent with a weight percentage of 10-50% to adjust the concentration and viscosity of the mixture, so that the mixture is convenient to use and apply, and less than the above range will be too thick and not convenient to apply and flow; and more than the above range will affect the curing efficiency.

[0092] The present application uses a photoinitiator with a weight percentage of 0.1-10% to start the polymerization reaction under light conditions, and less than the above range will produce fewer free radicals under light, which will make the curing process slower or even unable to effectively cure; and more than the above range will make the curing process faster and the reaction difficult to control.

[0093] The present application uses a leveling agent with a weight percentage of 0.1-5% to help the mixture spread uniformly on the substrate and reduce bubbles and surface defects; less than the above range will not be conducive to the spreading of the mixture; and more than the above range will be high in cost and spread too fast.

[0094] The present application uses a silane coupling agent with a weight percentage of 0.1-5% to enhance the adhesion between materials and improve the overall performance of the prepared resin material; less than the above range will not be conducive to the adhesion between materials, and more than the above range will be high in cost and high in adhesion.

[0095] As can be seen from the above, the present application prepares a resin mixture by using the aforementioned high-refractive optical monomer, and the prepared resin mixture has high refractive index and good light transmittance, is convenient to coat, can be quickly cured after light, and can be subjected to nanoimprinting after curing.

[0096] In an alternative embodiment, the resin mixture can include the following components in weight percent: solvent 10%, optical monomer of high refractive index 40%, diluent 30%, photoinitiator 10%, leveling agent 5%, silane coupling agent 5%.

[0097] In an alternative embodiment, the resin mixture can include the following components in weight percent: solvent 20%, optical monomer of high refractive index 45%, diluent 20%, photoinitiator 8%, leveling agent 2%, silane coupling agent 5%.

[0098] In an alternative embodiment, the resin mixture can include the following components in weight percent: solvent 30%, optical monomer of high refractive index 50%, diluent 10%, photoinitiator 6%, leveling agent 3.9%, silane coupling agent 0.1%.

[0099] In an alternative embodiment, the resin mixture can include the following components in weight percent: solvent 40%, optical monomer of high refractive index 30%, diluent 25%, photoinitiator 4%, leveling agent 0.1%, silane coupling agent 0.9%.

[0100] In an alternative embodiment, the resin mixture can include the following components in weight percent: solvent 50%, optical monomer of high refractive index 40%, diluent 9%, photoinitiator 0.4%, leveling agent 0.3%, silane coupling agent 0.3%.

[0101] In an alternative embodiment, the resin mixture can include the following components in weight percent: solvent 60%, optical monomer of high refractive index 10%, diluent 19%, photoinitiator 0.1%, leveling agent 10%, silane coupling agent 0.9%.

[0102] In an alternative embodiment, the resin mixture can include the following components in weight percent: solvent 79%, optical monomer of high refractive index 10%, diluent 10%, photoinitiator 0.1%, leveling agent 0.5%, silane coupling agent 0.4%.

[0103] In an alternative embodiment, the resin mixture can include the following components in weight percent: solvent 10%, optical monomer of high refractive index 79%, diluent 10%, photoinitiator 0.8%, leveling agent 0.1%, silane coupling agent 0.1%.

[0104] Alternatively, the solvent is at least one of propylene glycol methyl ether acetate (PGMEA), ethyl acetate, dichloromethane, ethanol, isopropyl alcohol, butyl acetate, butyl acetate, tetrahydrofuran, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), tetramethylethylenediamine, carbon tetrachloride. These solvents have solubility for a variety of substances, can have good phase solubility with each component, facilitate uniform mixing of each component, and facilitate removal.

[0105] Optionally, the diluent is at least one of polyethylene glycol phenylphenyl ether acrylate (OPPEA), EM2206 (a bifunctional acrylate monomer, available from Changxing Chemical Industry Co., Ltd., product name ETERMER 2206), and 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene. The above-mentioned diluents have good compatibility with other components of the resin mixture, and can adjust the concentration and viscosity of the resin mixture; the above-mentioned diluents are prone to polymerize around the high-refractive optical monomers of the present application, especially prone to polymerize with the unsaturated functional groups to form a large network structure, so that the resin mixture can be quickly cured.

[0106] In some examples, the light initiator has an absorption wavelength of 368 nm to 420 nm. The light initiator can be activated by irradiation of ultraviolet light at the above-mentioned wavelength, so that the light initiator can initiate the polymerization reaction under light irradiation conditions without affecting the overall light transmittance of the resin mixture after curing.

[0107] Optionally, the photoinitiator is at least one of acyloxyphosphine, thioxanthone and its derivatives, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxylic acid chloride, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxy-2-methyl ester, diethoxyacetophenone, 4-tert-butyltrichloroacetophenone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2-dimethylaminoethylbenzoate, 4,6-trimethylbenzoyldimethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, benzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiethoxyphenylphosphine oxide, benzoyldiethoxyphosphine oxide, benzophenone and its derivatives, benzoin and its derivatives, anthraquinone and its derivatives, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, p-dimethylaminoethylbenzoate, diphenyl disulfide, camphorquinone, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxylic acid, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxy-2-bromoethyl ester, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, alpha-aminoalkylphenone derivatives, phenyl-glyoxylic acid-methyl ester or oxy-phenyl-acetic acid 2-[2-oxy-2-phenyl-ethoxy-ethoxy]-ethyl ester and oxy-phenyl-acetic acid 2-[2-hydroxy-ethoxy]-ethyl ester. These photoinitiators can be quickly activated and produce active free radicals when irradiated by a light source, thereby initiating polymerization reactions between the various substances in the ultraviolet-resistant resin and further achieving curing. The photoinitiators in these embodiments mainly absorb light in the wavelength range of 368 nm to 420 nm.

[0108] Optionally, the leveling agent is one of BYK 331, BYK 370, BYK 3505, and BYK 348. Specifically, BYK 331, BYK 370, BYK 3505, and BYK 348 are leveling agents produced by BYK, Germany. The BYK series of leveling agents have excellent leveling performance.

[0109] Optionally, the silane coupling agent is one of KH570, KH550, and KH560. Specifically, KH570, KH550, and KH560 are silane coupling agents produced by the Chinese Academy of Sciences.

[0110] Among them, KH570 is also known as γ-methacryloxypropyltrimethoxysilane, which is an organic functional silane coupling agent. KH570 can improve the mechanical and electrical properties of resin materials.

[0111] KH550 is also known as gamma-aminopropyl triethoxysilane, which can enhance the adhesion of resin material, and improve the mechanical, water resistance, anti-aging and other properties of the product.

[0112] KH560 is also known as gamma-glycidyl ether propyl trimethoxysilane, which can improve the strength performance of the resin material.

[0113] Advantageously, the refractive index of the resin mixture is greater than 1.73, which has a high refractive index and is convenient for nanoimprint.

[0114] The application provides the application of the resin mixture, and when the resin mixture in the foregoing examples is coated on a substrate and cured, a resin material can be obtained and used for nanoimprint. Thus, when used for nanoimprint, the resin material has good shape retention and high light transmittance.

[0115] The application provides a preparation method of an optical monomer with a high refractive index, at least comprising the following steps:

[0116] S1, reacting the first monomer and the second monomer in the presence of ethanol and sodium ethoxide, and through extraction, solvent removal and purification treatment, obtaining a compound comprising a benzene sulfur ring group as a first product.

[0117] Optionally, the structural formula of the first monomer is as follows:

[0118] Optionally, the structural formula of the second monomer is as follows:

[0119] Optionally, the first monomer can be prepared through the following steps: reacting a reactant with a structural formula as shown in the following formula in a toluene solution, a sodium hydrosulfide solution and a tetrabutylammonium bromide solution at 55-65 DEG C, stirring and refluxing for 3-5 hours to obtain the first monomer with a structural formula as shown in the following formula . Exemplarily, the stirring and refluxing temperature is 55 DEG C, 60 DEG C or 65 DEG C, and the stirring and refluxing time is 3 hours, 4 hours or 5 hours.

[0120] S2, treating the first product to obtain a second product.

[0121] Exemplarily, the first product is stirred and refluxed in a toluene solution, a sodium hydrosulfide solution and a tetrabutylammonium bromide solution at 100-110 DEG C for 7-9 hours to obtain the second product. Exemplarily, the stirring and refluxing temperature is 100 DEG C, 105 DEG C or 110 DEG C, and the refluxing time is 7 hours, 8 hours or 9 hours.

[0122] S3, reacting the second product and the first product in the presence of ethanol and sodium ethoxide to obtain a compound with a hybrid unit as a third product.

[0123] S4, reacting the third product with a third monomer to generate a compound of a hybrid unit with multiple sulfurs at both ends of a chain, as a fourth product.

[0124] Optionally, the third monomer has the following structural formula:

[0125] Optionally, the third monomer and the third product are sequentially added and stirred under a nitrogen atmosphere at 0°C, and then stirred at room temperature for 32-40 hours. After extraction, drying, removal of the solvent, and purification, the fourth product is obtained. For example, the reaction is performed for 32 hours, 33 hours, 34 hours, 35 hours, 36 hours, 37 hours, 38 hours, 39 hours, or 40 hours.

[0126] S5, reacting the fourth product with a fourth monomer to generate an optical monomer with a high refractive index.

[0127] Optionally, the fourth monomer has the following structural formula:

[0128] Optionally, the fourth product and the fourth monomer are reacted in a dichloromethane solvent in the presence of triethylamine for 15-20 hours. For example, the reaction is performed for 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, or 20 hours.

[0129] The preparation method of the optical monomer with a high refractive index can obtain an optical monomer with the desired structure through multiple reactions. The prepared optical monomer has a high refractive index and heat resistance, and high visible light transmittance.

[0130] In some specific examples, the preparation conditions and reaction formula of the optical monomer with a high refractive index having the structural formula A-1 can refer to the following: Figure 8 For example, the specific reaction operation steps are as follows:

[0131] The reactant (compound f1 shown in the figure) having the structural formula is added to a toluene solution (800 mL), and then NaHS aqueous solution (16 g of NaHS dissolved in 100 g of water) and 0.8 g of tetrabutylammonium bromide are added. The mixture is stirred and refluxed at 60°C for 4 hours to obtain the first monomer (compound f2 shown in the figure) having the structural formula , 48.47 g, 55% yield.

[0132] Into the reaction apparatus, 1000 ml of anhydrous ethanol, the first monomer (compound f2 shown in the figure) (48.47 g, 172 mmol), the second monomer (compound f3 shown in the figure) (65 g, 350 mmol) were added under anhydrous and anaerobic conditions, and stirred at room temperature for 30 min. 24 g of sodium ethoxide was dissolved in 400 ml of anhydrous ethanol, and slowly added dropwise into the reaction apparatus, and refluxed at room temperature for 36 h. After the reaction was completed, saturated brine was added, and the organic layer was extracted with diethyl ether, and the solvent was removed under reduced pressure, and column chromatography was used for purification to obtain the first product (compound f4 shown in the figure), 26.91 g, 48% yield.

[0133] The first product (compound f4 shown in the figure) (26.91 g, 82.56 mmol) was added to a toluene solution (200 mL), and then NaHS aqueous solution (4 g of NaHS dissolved in 25 g of water) was added, and then 0.2 g of tetrabutylammonium bromide was added, and stirred and refluxed at 110°C for 8 h to obtain the second product (compound f shown in the figure), 15.95 g, 60% yield.

[0134] The second product (compound f shown in the figure) (15.09 g, 46.86 mmol), EtONa (6.8 g, 100 mmol), anhydrous ethanol (500 ml) were added at 0°C under a nitrogen atmosphere, and stirred for 1 h, and then the first product (compound f4 shown in the figure) (30.96 g, 95 mmol) was added at 0°C, and stirred for 1 h, and then the temperature was returned to room temperature and continued to be stirred for 36 h. After the reaction was completed, CH2Cl2was used for extraction, and the organic layer was dried using MgSO4. The solvent was removed under reduced pressure, and column chromatography was used for purification to obtain the third product (compound g shown in the figure), 22.46 g, 53% yield.

[0135] The third monomer (compound i shown in the figure) (5.1 g, 52 mmol), NaH (1.44 g, 60 mmol), anhydrous THF 200 ml were added at 0°C under a nitrogen atmosphere, and stirred for 1 h, and then the third product (compound g shown in the figure) (22.46 g, 24.83 mmol) was added at 0°C, and stirred for 1 h, and then the temperature was returned to room temperature and continued to be stirred for 18 h. After the reaction was completed, saturated brine was added at 0°C to quench the unreacted NaH, and CH2Cl2was used for extraction, and the organic layer was dried using MgSO4. The solvent was removed under reduced pressure, and column chromatography was used for purification to obtain the fourth product (compound k shown in the figure), 18.33 g, 72% yield.

[0136] The fourth product (compound k shown in the figure) (18.33 g, 17.82 mmol) and the fourth monomer (compound h shown in the figure) (3.6 g, 40 mmol) were reacted in dichloromethane solvent under the action of triethylamine for 17 h to obtain the high refractive optical monomer of compound structure A-1, 14.34 g, 71% yield.

[0137] That is, as shown in the following reaction steps, the high-refractive optical monomers of structural formula A-1, A-2, A-3, A-4, A-5, and A-6 can be prepared. Figures 2 to 7 Figure 8

[0138] Compared with the preparation of the high-refractive optical monomer of structural formula A-1, in the preparation of the high-refractive optical monomer of structural formula A-2, only the fourth monomer compound h is replaced by methacryloyl chloride.

[0139] Compared with the preparation of the high-refractive optical monomer of structural formula A-1, in the preparation of the high-refractive optical monomer of structural formula A-3, only the second monomer compound f3 is replaced by (1,2-dibromoethyl)benzene. The structures of the first product, the second product, the third product, and the fourth product are changed accordingly.

[0140] Compared with the preparation of the high-refractive optical monomer of structural formula A-1, in the preparation of the high-refractive optical monomer of structural formula A-4, only the second monomer compound f3 is replaced by (1,2-dibromoethyl)benzene, and the fourth monomer compound h is replaced by methacryloyl chloride. The structures of the first product, the second product, the third product, and the fourth product are changed accordingly.

[0141] Compared with the preparation of the high-refractive optical monomer of structural formula A-1, in the preparation of the high-refractive optical monomer of structural formula A-5, only the second monomer compound f3 is replaced by 1,2-dibromopropane. The structures of the first product, the second product, the third product, and the fourth product are changed accordingly.

[0142] Compared with the preparation of the high-refractive optical monomer of structural formula A-1, in the preparation of the high-refractive optical monomer of structural formula A-6, only the second monomer compound f3 is replaced by 1,2-dibromopropane, and the fourth monomer compound h is replaced by methacryloyl chloride. The structures of the first product, the second product, the third product, and the fourth product are changed accordingly.

[0143] The optical monomers and resin mixtures of the present application are further described below in connection with specific examples and test data.

[0144] Example 1

[0145] Preparation of the high-refractive optical monomer of structural formula A-1:

[0146] Reference can be made to Figure 8 ​​Compound f 1 (143 g, 312 mmol) was added to toluene solution (800 mL), NaHS aqueous solution (16 g of NaHS dissolved in 100 g of water) was added, 0.8 g of tetrabutylammonium bromide was added, and stirring was performed under reflux at 60°C for 4 h to obtain compound f 2, 48.47 g, 55% yield.

[0147] Compound f 2 (48.47 g, 172 mmol), compound f 3 (65 g, 350 mmol), and 1000 mL of anhydrous ethanol were added to a reaction device under anhydrous and anaerobic conditions, and stirring was performed at room temperature for 30 min. 24 g of sodium ethoxide was dissolved in 400 mL of anhydrous ethanol, and the solution was slowly added dropwise to the reaction device, and reaction was performed under reflux at room temperature for 36 h. After the reaction was completed, saturated brine was added, the organic layer was extracted with diethyl ether, the solvent was removed under reduced pressure, and column chromatography was performed to obtain compound f 4, 26.91 g, 48% yield.

[0148] Compound f 4 (26.91 g, 82.56 mmol) was added to toluene solution (200 mL), NaHS aqueous solution (4 g of NaHS dissolved in 25 g of water) was added, 0.2 g of tetrabutylammonium bromide was added, and stirring was performed under reflux at 110°C for 8 h to obtain compound f, 15.95 g, 60% yield.

[0149] Compound f (15.09 g, 46.86 mmol), EtONa (6.8 g, 100 mmol), and anhydrous ethanol (500 mL) were added at 0°C under a nitrogen atmosphere, and stirring was performed for 1 h. Compound f 4 (30.96 g, 95 mmol) was added at 0°C, stirring was performed for 1 h, and then stirring was performed at room temperature for 36 h. After the reaction was completed, extraction was performed with CH2Cl2, and the organic layer was dried using MgSO4. The solvent was removed under reduced pressure, and column chromatography was performed to obtain compound g, 22.46 g, 53% yield.

[0150] Compound i (5.1 g, 52 mmol), NaH (1.44 g, 60 mmol), and anhydrous THF (200 mL) were added at 0°C under a nitrogen atmosphere, and stirring was performed for 1 h. Compound g (22.46 g, 24.83 mmol) was added at 0°C, stirring was performed for 1 h, and then stirring was performed at room temperature for 18 h. After the reaction was completed, saturated brine was added at 0°C to quench unreacted NaH, extraction was performed with CH2Cl2, and the organic layer was dried using MgSO4. The solvent was removed under reduced pressure, and column chromatography was performed to obtain compound k, 18.33 g, 72% yield.

[0151] Compound k (18.33 g, 17.82 mmol) was reacted with compound h (3.6 g, 40 mmol) in dichloromethane solvent in the presence of triethylamine for 17 h to obtain a high refractive optical monomer of compound structure A-1, 14.34 g, 71% yield.

[0152] The compound f2 is the first monomer of the present application, the compound f3 is the second monomer of the present application; the compound f4 is the first product of the present application; the compound f is the second product of the present application; the compound g is the third product of the present application; the compound i is the third monomer of the present application; the compound k is the fourth product of the present application; and the compound h is the fourth monomer of the present application.

[0153] Preparation of resin mixture HIA-1: A 50 mL volumetric flask was added with propylene glycol methyl ether acetate (PGMEA) (10 g), A-1 (10 g), 9, 9-bis[4-(2-acryloyloxyethoxy) phenyl] fluorene (2 g), TPO (0.3 g), BYK370 (0.03 g), KH570 (0.05 g), and mixed vigorously for 2 h under light protection, and then filtered with a 0.45 μm needle filter to obtain the resin mixture.

[0154] The resin mixture was spin-coated on a 4-inch resin wafer (rotation speed 3500 rpm, time 60 s), and then subjected to grating imprinting to form a nanoimprint glue. The refractive index, light transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0155] Example 2

[0156] Preparation of a high refractive optical monomer of compound structure A-2: The overall process was the same as that of A-1, but compound h (i.e. the fourth monomer) was replaced with methacryloyl chloride.

[0157] Preparation of resin mixture HIA-2: A 50 mL volumetric flask was added with PGMEA (10 g), A-2 (10 g), 9, 9-bis[4-(2-acryloyloxyethoxy) phenyl] fluorene (2 g), TPO (0.3 g), BYK370 (0.03 g), KH570 (0.05 g), and mixed vigorously for 2 h under light protection, and then filtered with a 0.45 μm needle filter to obtain the resin mixture.

[0158] The resin mixture was spin-coated on a 4-inch resin wafer (rotation speed 3500 rpm, time 60 s), and then subjected to grating imprinting to form a nanoimprint glue. The refractive index, light transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0159] Example 3

[0160] Preparation of high refractive optical monomer with structure of A-3: the same procedure as A-1, but compound f3 (i.e. the second monomer) is replaced by (1,2-dibromoethyl)benzene.

[0161] Preparation of resin mixture HIA-3: PGMEA (10 g), A-3 (10 g), 9,9-bis[4-(2- acryloyloxyethoxy)phenyl]fluorene (2 g), TPO (0.3 g), BYK370 (0.03 g), KH570 (0.05 g) were added into a 50 mL volumetric flask, mixed vigorously for 2 h under dark condition, and then filtered by a 0.45 μιη needle filter to obtain the resin mixture.

[0162] The resin mixture was spin-coated on a 4-inch resin wafer (3500 rpm for 60 s) and then subjected to grating imprinting to form a nanoimprint glue. The refractive index, transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0163] Example 4

[0164] Preparation of high refractive optical monomer with structure of A-4: the same procedure as A-1, but compound f3 (i.e. the second monomer) is replaced by (1,2-dibromoethyl)benzene, and compound h (i.e. the fourth monomer) is replaced by methacryloyl chloride.

[0165] Preparation of resin mixture HIA-4: PGMEA (10 g), A-4 (10 g), 9,9-bis[4-(2- acryloyloxyethoxy)phenyl]fluorene (2 g), TPO (0.3 g), BYK370 (0.03 g), KH570 (0.05 g) were added into a 50 mL volumetric flask, mixed vigorously for 2 h under dark condition, and then filtered by a 0.45 μιη needle filter to obtain the resin mixture.

[0166] The resin mixture was spin-coated on a 4-inch resin wafer (3500 rpm for 60 s) and then subjected to grating imprinting to form a nanoimprint glue. The refractive index, transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0167] Example 5

[0168] Preparation of high refractive optical monomer with structure of A-5: the same procedure as A-1, but compound f3 (i.e. the second monomer) is replaced by 1,2-dibromopropane.

[0169] Preparation of resin mixture HIA-5: Add PGMEA (10g), A-5 (10g), 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene (2g), TPO (0.3g), BYK370 (0.03g), and KH570 (0.05g) to a 50mL volumetric flask. Mix vigorously for 2 hours under light-protected conditions. Filter the mixture through a 0.45μm syringe filter to obtain the resin mixture.

[0170] The resin mixture was homogenized on a 4-inch resin wafer (3500 rpm, 60 s), followed by grating imprinting to form a nanoimprint adhesive. Refractive index, transmittance, and grating structure parameters were measured using SEM.

[0171] Example 6

[0172] Preparation of high-refractive-index optical monomers with compound structure A-6: The process is the same as A-1, but compound f3 (i.e., the second monomer) is replaced with 1,2-dibromopropane, and compound h (i.e., the fourth monomer) is replaced with methacryloyl chloride.

[0173] Preparation of resin mixture HIA-6: Add PGMEA (10g), A-6 (10g), 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene (2g), photoinitiator TPO (0.3g), BYK370 (0.03g), and KH570 (0.05g) to a 50mL volumetric flask. Mix vigorously for 2h under light-protected conditions, and then filter through a 0.45μm syringe filter to obtain the resin mixture.

[0174] The resin mixture was homogenized on a 4-inch resin wafer (3500 rpm, 60 s), followed by grating imprinting to form a nanoimprint adhesive. Refractive index, transmittance, and grating structure parameters were measured using SEM.

[0175] Comparative Example 1

[0176] like Figure 9 and Figure 10 As shown, an optical monomer with the compound structural formula B-1 was prepared.

[0177] Compound g (89.78, 100 mmol) and compound h (18.45 g, 205 mmol) were reacted in dichloromethane solvent with triethylamine for 17 h to give compound B-1, 65.37 g, 65% yield.

[0178] Preparation of resin mixture HIB-1: PGMEA (10 g), B-1 (10 g), 9,9-bis[4-(2- acryloyloxyethoxy)phenyl]fluorene (2 g), TPO (0.3 g), BYK370 (0.03 g), KH570 (0.05 g) were added into a 50 mL volumetric flask, mixed vigorously for 2 h under dark condition, and then filtered using a 0.45 μm needle filter to obtain the resin mixture.

[0179] The resin mixture was spin-coated on a 4-inch resin wafer (spin speed: 3500 rpm, spin time: 60 s) and then subjected to grating imprinting to form a nanoimprint glue. The refractive index, light transmittance, grating structure SEM test, and grating structure parameter test were performed.

[0180] Comparative Example 2

[0181] As shown in Figure 11 , an optical monomer having the structural formula B-2 was prepared according to the preparation of B-1, except that the compound g was replaced by a compound having the structural formula .

[0182] Preparation of resin mixture HIB-2: PGMEA (10 g), B-2 (10 g), 9,9-bis[4-(2- acryloyloxyethoxy)phenyl]fluorene (2 g), TPO (0.3 g), BYK370 (0.03 g), KH570 (0.05 g) were added into a 50 mL volumetric flask, mixed vigorously for 2 h under dark condition, and then filtered using a 0.45 μm needle filter to obtain the resin mixture.

[0183] The resin mixture was spin-coated on a 4-inch resin wafer (spin speed: 3500 rpm, spin time: 60 s) and then subjected to grating imprinting to form a nanoimprint glue. The refractive index, light transmittance, grating structure SEM test, and grating structure parameter test were performed.

[0184] Comparative Example 3

[0185] As shown in Figure 12 , an optical monomer having the structural formula B-3 was prepared according to the preparation of B-1, except that the compound g was replaced by a compound having the structural formula .

[0186] Preparation of resin mixture HIB-3: PGMEA (10 g), B-3 (10 g), 9,9-bis[4-(2- acryloyloxyethoxy)phenyl]fluorene (2 g), TPO (0.3 g), BYK370 (0.03 g), KH570 (0.05 g) were added into a 50 mL volumetric flask, mixed vigorously for 2 h under dark condition, and then filtered using a 0.45 μm needle filter to obtain the resin mixture.

[0187] The resin mixture was spin-coated on a 4-inch resin wafer (rotation speed 3500 rpm, time 60 s) and then subjected to grating imprinting to form a nanoimprint glue. The refractive index, light transmittance, grating structure SEM test, and grating structure parameter test were performed.

[0188] Comparative Example 4

[0189] No optical monomer was added in this example.

[0190] A 50-mL volumetric flask was charged with PGMEA (10 g), 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene (10 g), photoinitiator TPO (0.3 g), BYK370 (0.03 g), and KH570 (0.05 g), and the mixture was stirred vigorously in the dark for 2 h. The resin mixture was filtered using a 0.45-μm needle filter to obtain a resin mixture.

[0191] The resin mixture was spin-coated on a 4-inch resin wafer (rotation speed 3500 rpm, time 60 s) and then subjected to grating imprinting to form a nanoimprint glue. The refractive index, light transmittance, grating structure SEM test, and grating structure parameter test were performed.

[0192] Solvents used in this example and comparative examples:

[0193] Solvent used: propylene glycol methyl ether acetate (PGMEA), purchased from ANJIE.

[0194] Photoinitiator: acylphosphine oxide (TPO), purchased from IGM;

[0195] Diluent used: 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene, purchased from TCI.

[0196] Leveling agent used: BYK370, purchased from BYK-Gardner, Germany;

[0197] Silane coupling agent used: KH570, purchased from ANJIE.

[0198] It should be noted that in the above examples, propylene glycol methyl ether acetate was selected as the solvent, acylphosphine oxide was selected as the photoinitiator, 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene was selected as the diluent, BYK370 was selected as the leveling agent, and KH570 was selected as the silane coupling agent, which were used together with the optical monomers having the structural formulas A-1, A-2, A-3, A-4, A-5, A-6, B-1, B-2, and B-3 to prepare the resin mixture for specific performance testing. However, other solvents, photoinitiators, diluents, leveling agents, and silane coupling agents listed in the present application also have similar effects and should be included in the protection scope of the present application.

[0199] The cured films obtained from each of the above Examples 1-6 and Comparative Examples 1-4 were subjected to performance tests, and the test results are shown in Table 1.

[0200] The performance test methods and standards are as follows:

[0201] (1) Refractive index: tested using an ellipsometer (ME-L Mueller Matrix Spectroscopic Ellipsometer, Acrylic Technology) ;

[0202] (2) Light transmittance: high-precision haze meter (HM-150, Murakami Color Research Laboratory) ;

[0203] (3) Yellowness: high-precision haze meter (HM-150, Murakami Color Research Laboratory) ;

[0204] (4) Grating parameter test: micro-nano structure was measured using an SEM (SU5000, Hitachi) ;

[0205] (5) Film layer thickness: film layer thickness was measured using an SEM (SU5000, Hitachi) ;

[0206] (6) Haze: high-precision haze meter (HM-150, Murakami Color Research Laboratory) ;

[0207] Table 1: Test performance comparison table of the cured films of the resin mixtures after grating imprinting of each of the examples and comparative examples

[0208]

[0209] From the test data of Examples 1-6 and Comparative Examples 1-4 in Table 1, it can be seen that:

[0210] The refractive index of the cured films in Examples 1-6 is all greater than 1.73, and all have a relatively high refractive index. The refractive index of Comparative Examples 1-4 is all smaller than that of the examples, which is caused by the small amount of sulfur in the mixture in Comparative Examples 1-3; and the refractive index of Comparative Example 4 is the smallest because of the multi-benzene ring structure.

[0211] The light transmittance of Examples 1-6 and Comparative Examples 1-4 is all greater than 90%, indicating that the structure of A-1, A-2, A-3, A-4, A-5, A-6, B-1, B-2, B-3, and 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene has a relatively high light transmittance.

[0212] The yellowness of Examples 1-6 and the comparative examples is all between 1 and 1.6.

[0213] In Examples 1-6, the microstructure surfaces were free of particles, and the surface molecules demolded well. In Comparative Examples 1-3, the microstructures contained particles, and the lack of long-chain sulfur alkanes on the surface negatively impacted demolding. Comparative Example 4 showed surface cracks, possibly because the rigid fluorene groups in the molecular chains made the material prone to stress accumulation during nanoimprint crosslinking and curing, which then developed into cracks during demolding.

[0214] Table 1 shows the design values ​​for the average height, width, and period of the microstructures in Examples 1-6 and Comparative Examples 1-3. Figure 13 As shown, the resin mixture containing compounds with structural formulas A-1, A-2, A-3, A-4, A-5, and A-6 in this invention exhibits excellent shape retention properties and can effectively replicate patterns on templates. The height of the nanoimprinted pattern is between 70 nm and 90 nm, and the width is between 140 nm and 160 nm. The structure of this invention also contains the three benzothiocyclic structures with structural formulas B-1, B-2, and B-3 mentioned above. Comparative Example 4 is a sulfur-free structure. The micro / nano structure of the sulfur-free resin mixture deviates significantly from the designed micro / nano period, indicating that a high sulfur content is beneficial for the encapsulation of micro / nano structures.

[0215] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An optical monomer having a high refractive index, characterized by, The optical monomer has a general structure formula (I) as follows: （I） wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 are each independently H; or, one of R1, R2 is H and the other is phenyl; one of R5, R6 is H and the other is phenyl; one of R9, R 10 is H and the other is phenyl; one of R3, R4 is H and the other is phenyl; one of R7, R8 is H and the other is phenyl; one of R 11 , R 12 is H and the other is phenyl; or, one of R1, R2 is H and the other is methyl; one of R5, R6 is H and the other is methyl; one of R9, R 10 is H and the other is methyl; one of R3, R4 is H and the other is methyl; one of R7, R8 is H and the other is methyl; one of R 11 , R 12 is H and the other is methyl. R 13 , R 14 each is independently H or methyl; n1, n2, n3 are each 1.

2. The high refractive optical monomer of claim 1, wherein, n1, n2, n3 are each 1, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 each are independently H, R 13 , R 14 each are independently H or methyl; The structure formula of the optical monomer is as follows (A-1) or (A-2): ; or, 。 3. The high refractive optical monomer of claim 1, wherein, n1, n2, n3 are each 1, R1, R3, R5, R7, R 11 each is independently phenyl, R2, R4, R6, R 10 , R 12 each is independently H; R 13 , R 14 each is independently H or methyl; The structure formula of the optical monomer is as follows (A-3) or (A-4): ; or, 。 4. The high refractive optical monomer of claim 1, wherein, n1, n2, n3 are each 1, R1, R3, R5, R7, R9, R 11 each is independently methyl, R2, R4, R6, R8, R 10 , R 12 each is independently H; R 13 , R 14 each is independently H or methyl; the optical monomer has a structure as shown in (A-5) or (A-6): ; or, 。 5. A resin mixture characterized in that, The resin mixture comprises the following components by weight percentage: Solvent 10%~79%; The optical monomer with high refractive index according to any one of claims 1-4 10%~79%; Diluent 10%~50%; Photoinitiator 0.1%~10%; Leveling agent 0.1%~5%; Silane coupling agent 0.1%~5%.

6. The resin mixture of claim 5, wherein, The solvent is at least one of propylene glycol methyl ether acetate, ethyl acetate, dichloromethane, ethanol, isopropyl alcohol, butyl acetate, butyl acetate, tetrahydrofuran, dimethyl sulfoxide, N,N-dimethylformamide, tetramethyl ethylenediamine, carbon tetrachloride.

7. The resin mixture of claim 5, wherein The diluent is at least one of propylene glycol methyl ether acetate, EM2206, 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene.

8. The resin mixture of claim 5, wherein, The absorption wavelength of the photoinitiator is 368nm~420nm; and / or, The photoinitiator is at least one of acyloxyphosphine, thioxanthone, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxylic acid chloride, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxy-2-methyl ester, diethoxyphenylacetophenone, 4-tert-butyltrichloroacetophenone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2-dimethylaminoethylbenzoate, 4,6-trimethylbenzoyldimethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, benzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiethoxyphenylphosphine oxide, benzoyldiethoxyphosphine oxide, benzophenone, benzoin, anthraquinone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, p-dimethylaminoethylbenzoate, diphenyl disulfide, camphorquinone, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxylic acid, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxy-2-bromoethyl ester, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropane-1-ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, alpha-aminoalkylphenone derivatives, phenyl-glyoxylic acid-methyl ester or oxy-phenyl-acetic acid 2-[2-oxy-2-phenyl-ethoxy-ethoxy]-ethyl ester and oxy-phenyl-acetic acid 2-[2-hydroxy-ethoxy]-ethyl ester.

9. The resin mixture of claim 5, wherein, The leveling agent is one of BYK331, BYK370, BYK3505, BYK348.

10. The resin mixture of claim 5, wherein The silane coupling agent is one of KH570, KH550, KH560.

11. The resin mixture of any one of claims 5-10, wherein, The refractive index of the resin mixture is greater than 1.

73.

12. Use of a resin mixture as claimed in any one of claims 5-11, characterized in that The resin mixture is used for nanoimprinting.

13. A method of producing the optical monomer of high refractive index as claimed in claim 1, characterized by, At least comprising the following steps: The first monomer and the second monomer are reacted in the presence of ethanol and sodium ethoxide, and a compound containing a benzothiophene group is obtained as a first product through extraction, solvent removal, and purification treatment; The first product is treated to generate a second product; The second product is reacted with the first product in the presence of ethanol and sodium ethoxide to generate a compound with a hybrid unit as a third product; The third product is reacted with a third monomer to generate a compound with a hybrid unit having multiple sulfurs connected to both ends of a chain as a fourth product; The fourth product is reacted with a fourth monomer to generate an optical monomer with a high refractive index; The first monomer has a structural formula of: ; The structural formula of the second monomer is: or or ; The third monomer has a structural formula of: ; The fourth monomer has a structural formula of: or .

14. The method for preparing a high-refractive-index optical monomer as described in claim 13, characterized in that, The treatment of the first product to generate the second product includes stirring the first product in a toluene solution, a sodium hydrosulfide solution, and tetrabutylammonium bromide at 100°C to 110°C for 7 hours to 9 hours under reflux to generate the second product.

15. The method for preparing a high-refractive-index optical monomer as described in claim 13, characterized in that, Also included is the reaction of a reactant having the structural formula in the presence of a toluene solution, a sodium hydrosulfide solution, and tetrabutylammonium bromide at 55°C to 65°C for 3 hours to 5 hours to form a first monomer having the structural formula .

16. The method for preparing a high-refractive-index optical monomer as described in claim 13, characterized in that, The reaction conditions for the reaction of the third product with the third monomer to generate a compound with a hybrid unit having multiple sulfurs connected to both ends of a chain include adding the third monomer and the third product successively under stirring at 0°C in a nitrogen atmosphere, stirring at room temperature for 32 hours to 40 hours, and obtaining the fourth product through extraction, drying, solvent removal, and purification.

17. The method for preparing a high-refractive-index optical monomer as described in claim 13, characterized in that, The reaction conditions for the reaction of the fourth product with the fourth monomer to generate an optical monomer with a high refractive index include reacting the fourth product with the fourth monomer in dichloromethane solvent in the presence of triethylamine for 15 hours to 20 hours.

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