Optical monomer with high refractive index, preparation method thereof, resin mixture and application thereof

Abstract

The invention relates to a high-refractive-index optical monomer and a preparation method thereof, a resin mixture and application thereof, and the high-refractive-index optical monomer comprises at least one group of hybrid units and two polysulfide chains respectively located at two end chains of the hybrid units; the hybrid unit comprises three benzosulfide rings connected through sulfur, and each benzosulfide ring comprises a benzene ring and two cyclohexyldithioalkyl groups connected with the benzene ring in a hybrid mode. According to the optical monomer with the high refractive index, a hybrid unit is rich in sulfur element, a benzene ring structure and a benzosulfide ring structure, and the structures have high molar refractive indexes, so that the whole molecule has a very high refractive index; and the benzene ring has certain rigidity, the structure is relatively stable, and the heat resistance of molecules can be improved. The polysulfide chain enables the chain length of the whole molecule to be increased and the flexibility to be improved. The polysulfide chain is rich in sulfur element, and interacts with the hybrid unit, so that penetration of visible light is facilitated. The optical monomer disclosed by the invention has relatively high visible light penetration rate, relatively high refractive index and good heat resistance.

Description

Technical Field

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

[0002] High-performance optical devices are increasingly moving towards lightweight, miniaturization, and integration. Nanoimprinting technology is used to transfer the designed pattern to a high-refractive-index optical resin to meet the needs of lightweight, miniaturization, and integration. The refractive index of resins currently available in the domestic market is less than 1.65, which greatly limits the application of materials and makes nanoimprinting impossible, or the transmittance after nanoimprinting is poor. Summary of the invention

[0003] In view of this, the present invention proposes an optical monomer with a high refractive index and a preparation method thereof, a resin mixture and an application thereof, aiming to achieve the performance of high refractive index and high light transmittance of the optical monomer.

[0004] The high refractive index optical monomer proposed in the first aspect of the present invention includes at least one group of hybrid units and two polysulfide chains respectively located at the two end chains of the hybrid unit; the hybrid unit includes three benzosulfide rings connected by sulfur, and each of the benzosulfide rings includes a benzene ring and two cyclohexyldisulfide groups hybridized with the benzene ring.

[0005] The high refractive index optical monomer proposed in the first aspect of the present invention is rich in sulfur elements, benzene ring structures, and benzosulfide ring structures in the hybrid unit. These structures themselves have a high molar refractive index, which makes the overall molecule have a high refractive index; and 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 entire molecule and improve the flexibility of the entire molecule. The polysulfide chain itself is rich in more sulfur elements with a high molar refractive index. The polysulfide chain and the hybrid unit together are conducive to separating chromophores and disrupting the intramolecular conjugated interactions, which helps the penetration of visible light. Then, the optical monomer of the present invention has a high visible light transmittance, and itself has a high refractive index and good heat resistance.

[0006] In some embodiments, the polysulfide chain includes 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 formula (I):

[0008]

[0009] Among them, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R12 Each is H or 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 One of arylalkylene and fluoroalkyl; R 13 , R 14 Each of them is H or methyl; n1, n2, n3 are positive integers of 1 to 50.

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

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

[0012]

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

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

[0015]

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

[0017]

[0018] The resin mixture proposed in the second aspect of the present invention comprises the following components in weight percentage: 10% to 79% solvent; 10% to 79% of the optical monomer with high refractive index of the aforementioned embodiments; 10% to 50% diluent; 0.1% to 10% photoinitiator; 0.1% to 5% leveling agent; and 0.1% to 5% silane coupling agent.

[0019] The resin mixture provided in the second aspect of the present invention has a relatively 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, isopropanol, butyl acetate, butyl acetate, tetrahydrofuran, dimethyl sulfoxide, N,N-dimethylformamide, tetramethylethylenediamine, and carbon tetrachloride.

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

[0022] In some embodiments, the absorption wavelength of the photoinitiator is 368nm to 420nm; and / or, the photoinitiator is acylphosphine oxide, 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-carboxyl-2-methyl ester, diethoxyacetophenone, 4-tert-butyltrichloroacetophenone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2-dimethylaminoethyl benzoate, 4,6-trimethylbenzoyldimethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, benzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiethoxyphenylphosphine oxide, benzoyldiethoxyphosphine oxide, benzophenone and its derivatives, benzil and its derivatives, anthracene Quinone and its derivatives, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, p-dimethylaminoethyl benzoate, 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-carboxylic acid-2-bromoethyl ester, 2-methyl At least one of 1-[4-(methylthio)phenyl-13-yl]-2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, an α-aminoalkylphenone derivative, 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 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 refractive index of the resin mixture is greater than 1.73.

[0026] The third aspect of the present invention provides an application of the resin mixture, wherein the resin mixture is used for nanoimprinting.

[0027] The resin mixture proposed in the third aspect of the present invention has good shape retention and high light transmittance when applied to nanoimprinting.

[0028] The fourth aspect of the present invention provides a method for preparing an optical monomer with a high refractive index, which comprises at least the following steps: reacting a first monomer and a second monomer in the presence of ethanol and sodium ethoxide, and obtaining a compound including a benzothiocyclic group as a first product through extraction, solvent removal and purification; treating the first product to generate a second product; reacting the second product with the first product in the presence of ethanol and sodium ethoxide to generate a compound having a hybrid unit as a third product; reacting the third product with a third monomer to generate a compound having a plurality of sulfur hybrid units connected to both end chains as a fourth product; and reacting the fourth product with a fourth monomer to generate an optical monomer with a high refractive index.

[0029] The fourth aspect of the present invention provides a method for preparing an optical monomer with a high refractive index. After multiple steps of reaction, an optical monomer with a desired structure can be obtained. The prepared optical monomer has a high refractive index and heat resistance, and has high visible light penetration.

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

[0031] The structural formula of the second monomer is: and / or,

[0032] The structural formula of the third monomer is: and / or,

[0033] The structural formula of the fourth monomer is:

[0034] In some embodiments, processing the first product to generate the second product includes: stirring and refluxing the first product at 100° C. to 110° C. for 7 h to 9 h in the presence of toluene solution, sodium hydrosulfide solution, and tetrabutylammonium bromide to generate the second product.

[0035] In some embodiments, the structural formula is The reactants are stirred and refluxed at 55°C to 65°C for 3h to 5h in the presence of toluene solution, sodium hydrosulfide solution and tetrabutylammonium bromide to generate a product having the structural formula The first monomer.

[0036] In some embodiments, the third product is reacted with the third monomer to generate a compound having multiple sulfur hybrid units connected at both end chains, and the reaction conditions include: adding the third monomer and the third product in sequence and stirring at 0°C and nitrogen atmosphere, stirring the reaction at room temperature for 32h to 40h, and obtaining the fourth product after extraction, drying, removing the solvent, and purification.

[0037] In some embodiments, the reaction conditions for reacting 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 the presence of dichloromethane solvent and triethylamine for 15 hours to 20 hours.

[0038] It should be understood that the above general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure of the embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained like these accompanying drawings without paying any creative work.

[0040] Figure 1 is the general structural formula I of the optical monomer with high refractive index proposed in some embodiments of the present invention;

[0041] Figure 2 The compound structural formula A-1 proposed by the present invention is a high refractive index optical monomer;

[0042] Figure 3 The compound structural formula A-2 proposed by the present invention is a high refractive index optical monomer;

[0043] Figure 4 The compound structural formula A-3 is a high refractive index optical monomer proposed by the present invention;

[0044] Figure 5The compound structural formula A-4 is a high refractive index optical monomer proposed by the present invention;

[0045] Figure 6 The compound structural formula A-5 proposed by the present invention is a high refractive index optical monomer;

[0046] Figure 7 The compound structural formula A-6 proposed by the present invention is a high refractive index optical monomer;

[0047] Figure 8 The method for preparing the optical monomer with high refractive index having the compound structural formula A-1 proposed in some embodiments of the present invention includes multiple steps of reaction.

[0048] Fig. 9 It is a schematic diagram of structural formula B-1 of the optical monomer in comparative example 1 of the present invention.

[0049] Fig.10 It is a schematic diagram of the preparation reaction of the optical monomer proposed in Comparative Example 1 of the present invention.

[0050] Fig.11 It is a schematic diagram of structural formula B-2 of the optical monomer in comparative example 2 of the present invention.

[0051] Fig.12 It is a schematic diagram of structural formula B-3 of the optical monomer in comparative example 3 of the present invention.

[0052] Fig.13 It is a cross-sectional view of the micro-nano structure after nanoimprinting of the resin mixture of the present invention. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, other embodiments obtained by ordinary technicians in this field without creative work are all within the scope of protection of the present invention.

[0054] It should also be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0055] It should be further understood that the term "and / or" used in the present specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0056] The refractive index of existing commercially available resins is less than 1.65, which makes nanoimprinting impossible or has poor light transmittance after nanoimprinting, affecting product performance.

[0057] In view of this, an embodiment of the present invention provides an optical monomer 100 with a high refractive index, such as Figures 1 to 7 As shown, it includes at least one group of hybrid units and two polysulfide chains located at the two end chains of the hybrid unit respectively; the hybrid unit includes three benzosulfide rings connected by sulfur, and each benzosulfide ring includes a benzene ring and two cyclohexyldisulfide groups hybridly connected to the benzene ring.

[0058] Therefore, the optical monomer with high refractive index proposed by the present invention is rich in sulfur elements and benzosulfide ring structures in the hybrid unit. Due to its special electronic structure and atomic radius, the S element slows down the propagation speed of light when passing through these materials, thereby increasing the refractive index; the S element itself has the characteristics of high molar refractive index and low molecular dispersion, and can also provide a certain chain flexibility, which is convenient for reacting with other functional groups and forming connections. The benzosulfide ring itself has a high refractive index, and the benzosulfide ring has a conjugated structure, which slows down the propagation speed of light when passing through, and increases the refractive index. Therefore, the hybrid unit in the present invention can make the overall molecule have a very high refractive index.

[0059] In addition, after the benzene ring and the cyclohexanedisulfanyl group are connected in the present invention, they themselves have a certain rigidity and a relatively stable structure, which can improve the heat resistance of the molecule.

[0060] The polysulfide chain of the present invention can increase the chain length of the entire molecule, improve the flexibility of the entire molecule, reduce birefringence and improve transparency by increasing chain flexibility. The polysulfide chain itself is rich in sulfur elements with a high molar refractive index. The polysulfide chain and the hybrid unit are conducive to separating chromophores and disrupting the intramolecular conjugated interaction, thereby increasing the refractive index of the entire molecule and facilitating the penetration of visible light. The longer polysulfide chain also has a unique infrared transmission property.

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

[0062] It is understandable that compared with the defects of low refractive index and poor penetration of visible light in the optical monomers used to prepare resins in the prior art, the high refractive index optical monomers of the present invention have high refractive index, high light transmittance and certain heat resistance.

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

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

[0065] Optionally, the unsaturated functional group may be in a structural form such as C=C, C=O, etc., and it is necessary to simultaneously consider controlling the cost of the reactants within a reasonable range and facilitating the reaction.

[0066] In some embodiments, Figure 1 As shown, the optical monomer has the following general structural formula (I):

[0067]

[0068] Among them, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 Each is H or 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 One of arylalkylene and fluoroalkyl; R 13 , R 14 Each of them is H or methyl; n1, n2, n3 are positive integers of 1 to 50.

[0069] 43, 44, 45, 46, 47, 48, 49 or 50 respectively.

[0070] When the above-mentioned groups include long-chain alkane structures, the overall steric hindrance is small, the chemical bonds can rotate freely, and when impacted by external forces, stress transfer can be achieved, thereby making the molecules have better flexibility.

[0071] When the above group includes an alkylene ether group, the rotation of the molecular chain can be improved, thereby making the flexibility of the entire molecule 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, it has both certain flexibility and hardness.

[0074] When the above groups include fluoroalkyl groups, the lubricity of the molecule can be improved. Fluorine atoms have strong electronegativity and small atomic radius. When they replace hydrogen atoms in alkanes, the electron cloud distribution of the carbon chain will change. This change reduces the flexibility of the carbon chain and makes the molecular structure more rigid and stable. During the lubrication process, the rigid molecular structure can better withstand pressure and shear force, maintain the integrity of the lubricating film, and thus exhibit good lubricity. At the same time, the introduction of fluorine atoms reduces the surface energy of the molecule. The low surface energy makes it easier for fluoroalkanes to spread on the friction interface to form a uniform lubricating film, reduce direct contact between friction surfaces, and reduce the friction coefficient, thereby exhibiting lubricity.

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

[0076] As can be seen from the above, the optical monomer of the present invention is roughly symmetrically arranged with the hybrid unit as the center, so that the entire molecule contains more S elements. The molecular structure is rich in S elements, benzothiocyclic structures and other structures with high molar refractive index, so that the entire molecule can achieve high refractive index and high visible light transmittance.

[0077] In some embodiments, n1, n2, and n3 are 1 respectively, and R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 They are H, R 13 , R 14 Each is H or methyl; Figure 2 and Figure 3 As shown, the structural formula of the optical monomer is as follows (A-1) or (A-2):

[0078]

[0079] In A-1, R 13 , R14 Each is H; in A-2, R 13 , R 14 Each is a methyl group.

[0080] In some embodiments, n1, n2, and n3 are 1 respectively, and R1, R3, R5, R7, R9, and R 11 Each of them is phenyl, R2, R4, R6, R8, R 10 , R 12 They are H; R 13 , R 14 Each is H or methyl; Figure 4 and Figure 5 As shown, the structural formula of the optical monomer is as follows (A-3) or (A-4):

[0081]

[0082] In A-3, R 13 , R 14 Each is H; in A-4, R 13 , R 14 Each is a methyl group.

[0083] In some embodiments, n1, n2, and n3 are 1 respectively, and R1, R3, R5, R7, R9, and R 11 Each of them is methyl, R2, R4, R6, R8, R 10 , R 12 They are H; R 13 , R 14 Each is H or methyl; Figure 6 and Figure 7 As shown, the structural formula of the optical monomer is as follows (A-5) or (A-6):

[0084]

[0085] In A-5, R 13 , R 14 Each is H; in A-6, R 13 , R 14 Each is a methyl group.

[0086] In the above examples, compounds A-1, A-2, A-3, A-4, A-5 and A-6 all have three benzosulfide rings, and the benzene rings of the benzosulfide rings at both ends are connected with three sulfurs and C=O and C=C, respectively, so that the molecules are small and consume less material, and high refractive index and high transmittance are achieved, and the entire molecular end has active sites.

[0087] Of course, in other embodiments, the optical monomer with a high refractive index may also be of other structures, mainly including the aforementioned hybrid units and polysulfide chains, within the scope of the above general formula.

[0088] The present invention proposes a resin mixture, which includes the following components in weight percentage: 10% to 79% of a solvent; 10% to 79% of the optical monomer with a high refractive index according to the above-mentioned embodiments; 10% to 50% of a diluent; 0.1% to 10% of a photoinitiator; 0.1% to 5% of a leveling agent; and 0.1% to 5% of a silane coupling agent.

[0089] It is understandable that the present invention uses a solvent with a weight percentage of 10% to 79% to mix the components evenly. If it is lower than the above range, the components will not be mixed evenly and the compatibility will be reduced; if it is higher than the above range, the effective components will be too few.

[0090] The present invention uses optical monomers in a weight percentage of 10% to 79% to make the resin mixture have a high refractive index, high transmittance and thermal stability after curing. If it is lower than the above range, the refractive index of the mixture after curing will be insufficient and the consumables will increase; if it is higher than the above range, it will be unfavorable for film formation.

[0091] The present invention uses a diluent with a weight percentage of 10% to 50% to adjust the concentration and viscosity of the mixture, making the mixture easy to use and apply. If it is lower than the above range, it is too concentrated and not easy to apply, and the fluidity is too low; if it is higher than the above range, the curing efficiency is affected.

[0092] The present invention uses a photoinitiator with a weight percentage of 0.1% to 10% to start the polymerization reaction under light conditions. If the weight percentage is lower than the above range, fewer free radicals will be generated under light, which will slow down the curing process or even prevent effective curing; if the weight percentage is higher than the above range, the curing process will be faster and the reaction will be difficult to control.

[0093] The present invention uses a leveling agent with a weight percentage of 0.1% to 5% to help the mixed liquid spread evenly on the substrate and reduce bubbles and surface defects; below the above range is not conducive to the spreading of the mixed liquid; above the above range, the cost is high and the spreading is too fast.

[0094] The present invention uses 0.1% to 5% by weight of silane coupling agent to enhance the adhesion between materials, thereby improving the overall performance of the prepared resin material; if it is lower than the above range, it is not conducive to sufficient adhesion between materials, and if it is higher than the above range, the cost is high and the viscosity is too high.

[0095] As can be seen from the above, the present invention adopts the aforementioned optical monomer with a high refractive index to prepare a resin mixture. The prepared resin mixture has a high refractive index and good light transmittance, is easy to coat, can be quickly cured after illumination, and can be nano-imprinted after curing.

[0096] In an optional embodiment, the resin mixture may include the following components in weight percentage: 10% solvent, 40% optical monomer with high refractive index, 30% diluent, 10% photoinitiator, 5% leveling agent, and 5% silane coupling agent.

[0097] In an optional embodiment, the resin mixture may include the following components in weight percentage: 20% solvent, 45% optical monomer with high refractive index, 20% diluent, 8% photoinitiator, 2% leveling agent, and 5% silane coupling agent.

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

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

[0100] In an optional embodiment, the resin mixture may include the following components in weight percentage: 50% solvent, 40% optical monomer with high refractive index, 9% diluent, 0.4% photoinitiator, 0.3% leveling agent, and 0.3% silane coupling agent.

[0101] In an optional embodiment, the resin mixture may include the following components in weight percentage: 60% solvent, 10% optical monomer with high refractive index, 19% diluent, 0.1% photoinitiator, 10% leveling agent, and 0.9% silane coupling agent.

[0102] In an optional embodiment, the resin mixture may include the following components in weight percentage: 79% solvent, 10% optical monomer with a high refractive index, 10% diluent, 0.1% photoinitiator, 0.5% leveling agent, and 0.4% silane coupling agent.

[0103] In an optional embodiment, the resin mixture may include the following components in weight percentage: 10% solvent, 79% optical monomer with high refractive index, 10% diluent, 0.8% photoinitiator, 0.1% leveling agent, and 0.1% silane coupling agent.

[0104] Optionally, the solvent is at least one of propylene glycol methyl ether acetate (PGMEA), ethyl acetate, dichloromethane, ethanol, isopropanol, butyl acetate, butyl acetate, tetrahydrofuran, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), tetramethylethylenediamine, and carbon tetrachloride. These solvents have the ability to dissolve a variety of substances, have good compatibility with each component, facilitate mixing of each component uniformly, and facilitate removal.

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

[0106] In some examples, the absorption wavelength of the photoinitiator is 368nm to 420nm. The photoinitiator can be excited and activated under the illumination of ultraviolet light of the above wavelength, so that the photoinitiator can start the polymerization reaction under the illumination condition without affecting the overall light transmittance of the resin mixture after curing.

[0107] Optionally, the photoinitiator is acylphosphine oxide, 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-carboxyl-2-methyl ester, diethoxyacetophenone, 4-tert-butyltrichloroacetophenone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2-dimethylaminoethyl benzoate, 4,6-trimethylbenzoyldimethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, benzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiethoxyphenylphosphine oxide, benzoyldiethoxyphosphine oxide, benzophenone and its derivatives, benzil and its derivatives, anthraquinone and its derivatives, benzoin, benzoin methyl ether , benzoin ethyl ether, benzoin propyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, p-dimethylaminoethyl benzoate, 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-13-yl]-2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, α-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. When these photoinitiators are irradiated by light, they can be quickly activated and generate active free radicals, thereby initiating polymerization reactions between various substances in the anti-ultraviolet resin, and further achieving curing. The photoinitiators in these embodiments mainly absorb light within the wavelength range of 368nm to 420nm.

[0108] Optionally, the leveling agent is one of BYK331, BYK370, BYK3505 and BYK348. Specifically, BYK331, BYK370, BYK3505 and BYK348 are leveling agents produced by BYK of Germany. BYK series 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 is used to improve the mechanical and electrical properties of resin materials.

[0111] Among them, KH550, also known as γ-aminopropyltriethoxysilane, can enhance the adhesion of resin materials and improve the mechanical, water-resistant and anti-aging properties of products.

[0112] Among them, KH560, also known as γ-glycidyloxypropyltrimethoxysilane, can improve the strength properties of resin materials.

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

[0114] The present invention proposes the use of a resin mixture. When the resin mixture in the above examples is coated on a substrate and cured, a resin material can be obtained and used for nanoimprinting. Therefore, when used for nanoimprinting, the resin material has good shape retention and high light transmittance.

[0115] The present invention provides a method for preparing an optical monomer with a high refractive index, which comprises at least the following steps:

[0116] S1. The first monomer and the second monomer are reacted in the presence of ethanol and sodium ethoxide, and a compound including a benzothiocyclic group is obtained as a first product through extraction, solvent removal and purification.

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

[0118] Optionally, the second monomer has the structural formula:

[0119] Optionally, the first monomer can be prepared by the following steps: The reactants are stirred and refluxed at 55°C to 65°C for 3h to 5h in the presence of toluene solution, sodium hydrosulfide solution and tetrabutylammonium bromide to generate a product having the structural formula For example, the stirring reflux temperature is 55° C., 60° C., and 65° C.; and the stirring reflux time is 3 h, 4 h, and 5 h.

[0120] S2. Processing the first product to generate a second product.

[0121] Exemplarily, the first product is stirred and refluxed at 100° C. to 110° C. for 7 h to 9 h in the presence of toluene solution, sodium hydrosulfide solution, and tetrabutylammonium bromide to generate the second product. Exemplarily, the stirring and reflux temperature is 100° C., 105° C., and 110° C. The reflux time is 7 h, 8 h, and 9 h.

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

[0123] S4. The third product is reacted with the third monomer to generate a compound having a plurality of sulfur hybrid units connected to both end chains, as the fourth product.

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

[0125] Optionally, at 0°C and in a nitrogen atmosphere, the third monomer and the third product are added successively and stirred, and the mixture is stirred and reacted for 32 to 40 hours at room temperature, and the fourth product is obtained after extraction, drying, solvent removal, and purification. Exemplarily, the reaction is carried out for 32 hours, 33 hours, 34 hours, 35 hours, 36 hours, 37 hours, 38 hours, 39 hours, and 40 hours.

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

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

[0128] Optionally, the fourth product and the fourth monomer are reacted in the presence of dichloromethane solvent and triethylamine for 15 to 20 hours. Exemplarily, the reaction is carried out for 15 hours, 16 hours, 17 hours, 18 hours, 19 hours or 20 hours.

[0129] The method for preparing an optical monomer with a high refractive index provided by the present invention can obtain an optical monomer with a desired structure through a multi-step reaction. The prepared optical monomer has a high refractive index and heat resistance and high visible light penetration.

[0130] In some specific examples, the preparation conditions and reaction formula of the high refractive index optical monomer of compound structure A-1 can be referred to Figure 8 As shown. Exemplarily, the specific reaction steps are as follows:

[0131] The structural formula is The reactant (compound f1 shown in the figure) (143 g, 312 mmol) was added to a toluene solution (800 mL), and then an aqueous NaHS solution (16 g of NaHS was dissolved in 100 g of water) was added, and then 0.8 g of tetrabutylammonium bromide was added, and the mixture was stirred and refluxed at 60° C. for 4 h to obtain a structure of The first monomer (compound f2 shown in the figure), 48.47 g, 55% yield.

[0132] 1000 ml of anhydrous ethanol, the first monomer (the illustrated compound f2) (48.47 g, 172 mmol), and the second monomer (the illustrated compound f3) (65 g, 350 mmol) were added to the reaction device under anhydrous and oxygen-free 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 to the reaction device, and refluxed at room temperature for 36 h. After the reaction was completed, saturated brine was added, the organic layer was extracted with ether, the solvent was removed under reduced pressure, and the first product (the illustrated compound f4) was purified by column chromatography, 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 an aqueous NaHS solution (4 g of NaHS was dissolved in 25 g of water) was added, and then 0.2 g of tetrabutylammonium bromide was added. The mixture was 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] At 0°C, in a nitrogen atmosphere, the second product (the compound f shown in the figure) (15.09 g, 46.86 mmol), EtONa (6.8 g, 100 mmol), and anhydrous ethanol (500 ml) were added, stirred for 1 h, and the first product (the compound f4 shown in the figure) (30.96 g, 95 mmol) was added at 0°C, stirred for 1 h, and then returned to room temperature and continued to stir for 36 h. After the reaction was completed, it was extracted with CH2Cl2, and the organic layer was dried with MgSO4. The solvent was removed under reduced pressure, and purified by column chromatography to obtain the third product (the compound g shown in the figure), 22.46 g, 53% yield.

[0135] At 0°C, in a nitrogen atmosphere, add the third monomer (compound i shown in the figure) (5.1 g, 52 mmol), NaH (1.44 g, 60 mmol), and anhydrous THF 200 ml, stir for 1 h, add the third product (compound g shown in the figure) (22.46 g, 24.83 mmol) at 0°C, stir for 1 h, then return to room temperature and continue stirring for 18 h. After the reaction is completed, add saturated salt water to the system at 0°C to quench the unreacted NaH, extract with CH2Cl2, and dry the organic layer with MgSO4. Remove the solvent under reduced pressure, purify by column chromatography, and obtain 18.33 g of the fourth product (compound k shown in the figure) with a yield of 72%.

[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 hours to obtain a high refractive index optical monomer with compound formula A-1, 14.34 g, 71% yield.

[0137] That is to say, Figure 2-Figure 7 As shown, the optical monomers with high refractive index of the structural formula A-1, A-2, A-3, A-4, A-5 and A-6 of the present invention can be obtained by Figure 8 The preparation is carried out by similar reaction steps as shown.

[0138] Compared with the preparation of the high-refractive-index optical monomer of structural formula A-1, when preparing the high-refractive-index optical monomer of structural formula A-2, it is only necessary to replace compound h, the fourth monomer, with methacryloyl chloride.

[0139] Compared with the preparation of the high refractive index optical monomer of structural formula A-1, when preparing the high refractive index optical monomer of structural formula A-3, it is only necessary to replace compound f3, the second monomer, with (1,2-dibromoethyl)benzene. The structures of the first product, the second product, the third product, and the fourth product all change accordingly.

[0140] Compared with the preparation of the high refractive index optical monomer of structural formula A-1, when preparing the high refractive index optical monomer of structural formula A-4, it is only necessary to replace compound f3, the second monomer, with (1,2-dibromoethyl)benzene, and replace compound h, the fourth monomer, with methacryloyl chloride. The structures of the first product, the second product, the third product, and the fourth product all change accordingly.

[0141] Compared with the preparation of the high refractive index optical monomer of structural formula A-1, when preparing the high refractive index optical monomer of structural formula A-5, it is only necessary to replace compound f3, the second monomer, with 1,2-dibromopropane. The structures of the first product, the second product, the third product, and the fourth product all change accordingly.

[0142] Compared with the preparation of the high refractive index optical monomer of structural formula A-1, when preparing the high refractive index optical monomer of structural formula A-6, it is only necessary to replace compound f3, the second monomer, with 1,2-dibromopropane and compound h, the fourth monomer, with methacryloyl chloride. The structures of the first product, the second product, the third product and the fourth product all change accordingly.

[0143] The optical monomer and the resin mixture of the present invention are further described below in conjunction with specific examples and test data.

[0144] Example 1

[0145] Preparation of high refractive index optical monomer with compound structural formula A-1:

[0146] For reference Figure 8Compound f1 (143 g, 312 mmol) was added to a toluene solution (800 mL), followed by a NaHS aqueous solution (16 g of NaHS dissolved in 100 g of water), and then 0.8 g of tetrabutylammonium bromide. The mixture was stirred and refluxed at 60° C. for 4 h to obtain compound f2, 48.47 g, with a yield of 55%.

[0147] 1000 ml of anhydrous ethanol, compound f2 (48.47 g, 172 mmol), and compound f3 (65 g, 350 mmol) were added to the reaction apparatus under anhydrous and oxygen-free 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 to the reaction apparatus, and refluxed at room temperature for 36 h. After the reaction was completed, saturated brine was added, the organic layer was extracted with ether, the solvent was removed under reduced pressure, and column chromatography was used for purification to obtain compound f4, 26.91 g, 48% yield.

[0148] Compound f4 (26.91 g, 82.56 mmol) was added to a toluene solution (200 mL), followed by a NaHS aqueous solution (4 g of NaHS dissolved in 25 g of water), and then 0.2 g of tetrabutylammonium bromide. The mixture was stirred and refluxed at 110° C. for 8 h to obtain compound f, 15.95 g, with a yield of 60%.

[0149] At 0°C, in a nitrogen atmosphere, compound f (15.09 g, 46.86 mmol), EtONa (6.8 g, 100 mmol), and anhydrous ethanol (500 ml) were added, stirred for 1 h, and compound f4 (30.96 g, 95 mmol) was added at 0°C, stirred for 1 h, and then returned to room temperature and continued to stir for 36 h. After the reaction was completed, it was extracted with CH2Cl2, and the organic layer was dried with MgSO4. The solvent was removed under reduced pressure, and purified by column chromatography to obtain compound g, 22.46 g, 53% yield.

[0150] At 0°C, in a nitrogen atmosphere, compound i (5.1 g, 52 mmol), NaH (1.44 g, 60 mmol), and anhydrous THF 200 ml were added, stirred for 1 h, and compound g (22.46 g, 24.83 mmol) was added at 0°C, stirred for 1 h, and then returned to room temperature and continued to stir for 18 h. After the reaction was completed, saturated saline was added to the system at 0°C to quench the unreacted NaH, extracted with CH2Cl2, and the organic layer was dried with MgSO4. The solvent was removed under reduced pressure, and purified by column chromatography to obtain 18.33 g of compound k with a yield of 72%.

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

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

[0153] Preparation of resin mixture HIA-1: Add 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), and KH570 (0.05 g) into a 50 mL volumetric flask, mix vigorously for 2 h in the dark, and then filter with a 0.45 μm syringe filter to obtain a resin mixture.

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

[0155] Example 2

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

[0157] Preparation of resin mixture HIA-2: 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), and KH570 (0.05 g) were added to a 50 mL volumetric flask, and the mixture was vigorously mixed for 2 h in the dark. After filtering with a 0.45 μm syringe filter, a resin mixture was obtained.

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

[0159] Example 3

[0160] Preparation of a high refractive index optical monomer with a compound structural formula A-3: The process is the same as A-1, but the 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), and KH570 (0.05 g) were added to a 50 mL volumetric flask, and the mixture was vigorously mixed for 2 h in the dark. After filtering with a 0.45 μm syringe filter, a resin mixture was obtained.

[0162] The resin mixture was spread on a 4-inch resin wafer (rotation speed 3500rpm, time 60s), and then grating imprinting was performed to form a nanoimprinting glue. The refractive index, transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0163] Example 4

[0164] Preparation of a high refractive index optical monomer with a compound structure of A-4: The process is the same as A-1, but the compound f3 (i.e., the second monomer) is replaced by (1,2-dibromoethyl)benzene, and the 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), and KH570 (0.05 g) were added to a 50 mL volumetric flask, and the mixture was vigorously mixed for 2 h in the dark. After filtering with a 0.45 μm syringe filter, a resin mixture was obtained.

[0166] The resin mixture was spread on a 4-inch resin wafer (rotation speed 3500rpm, time 60s), and then grating imprinting was performed to form a nanoimprinting glue. The refractive index, transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0167] Example 5

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

[0169] Preparation of resin mixture HIA-5: Add PGMEA (10 g), A-5 (10 g), 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene (2 g), TPO (0.3 g), BYK370 (0.03 g), and KH570 (0.05 g) into a 50 mL volumetric flask, mix vigorously for 2 h in the dark, and then filter with a 0.45 μm syringe filter to obtain a resin mixture.

[0170] The resin mixture was spread on a 4-inch resin wafer (rotation speed 3500rpm, time 60s), and then grating imprinting was performed to form a nanoimprinting glue. The refractive index, transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0171] Example 6

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

[0173] Preparation of resin mixture HIA-6: PGMEA (10 g), A-6 (10 g), 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene (2 g), photoinitiator TPO (0.3 g), BYK370 (0.03 g), and KH570 (0.05 g) were added to a 50 mL volumetric flask, and the mixture was vigorously mixed for 2 h in the dark. After filtering with a 0.45 μm syringe filter, a resin mixture was obtained.

[0174] The resin mixture was spread on a 4-inch resin wafer (rotation speed 3500rpm, time 60s), and then grating imprinting was performed to form a nanoimprinting glue. The refractive index, transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0175] Comparative Example 1

[0176] like Fig. 9 and Fig.10 As shown, an optical monomer having a compound structural formula of B-1 is prepared.

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

[0178] Preparation of resin mixture HIB-1: Add 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), and KH570 (0.05 g) into a 50 mL volumetric flask, mix vigorously for 2 h in the dark, and then filter with a 0.45 μm syringe filter to obtain a resin mixture.

[0179] The resin mixture was spread on a 4-inch resin wafer (rotation speed 3500rpm, time 60s), and then grating imprinting was performed to form a nanoimprinting glue. The refractive index, transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0180] Comparative Example 2

[0181] like Fig.11 As shown, an optical monomer having a compound structure of B-2 is prepared, and the preparation is the same as B-1, except that compound g is replaced by a compound having a structure of of compounds.

[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), and KH570 (0.05 g) were added to a 50 mL volumetric flask, and the mixture was vigorously mixed for 2 h in the dark. After filtering with a 0.45 μm syringe filter, a resin mixture was obtained.

[0183] The resin mixture was spread on a 4-inch resin wafer (rotation speed 3500rpm, time 60s), and then grating imprinting was performed to form a nanoimprinting glue. The refractive index, transmittance, grating structure SEM test, and grating structure parameter test were measured.

[0184] Comparative Example 3

[0185] like Fig.12 As shown, an optical monomer having a compound structure of B-3 is prepared. The preparation of B-3 is the same as B-1, except that compound g is replaced by a compound having a structure of of compounds.

[0186] Preparation of resin mixture HIB-3: Add 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), and KH570 (0.05 g) into a 50 mL volumetric flask, mix vigorously for 2 h in the dark, and then filter with a 0.45 μm syringe filter to obtain a resin mixture.

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

[0188] Comparative Example 4

[0189] In this embodiment, no optical monomer is added.

[0190] 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) were added to a 50 mL volumetric flask, mixed vigorously for 2 h in the dark, and then filtered through a 0.45 μm syringe filter to obtain a resin mixture.

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

[0192] The solvents used in this embodiment and comparative example are:

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

[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, Germany;

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

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

[0199] The performance of the cured films obtained in the above-mentioned Examples 1-6 and Comparative Examples 1-4 was tested. The test results are shown in Table 1.

[0200] Among them, the performance test methods and standards are as follows:

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

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

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

[0204] (4) Grating parameter test: Use SEM (SU5000 Hitachi) to measure the micro-nano structure;

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

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

[0207] Table 1 Comparison table of test properties of cured films of resin mixtures after grating imprinting in various embodiments 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 greater than 1.73, and all have relatively high refractive indexes. The refractive index of Comparative Examples 1-4 is smaller than that of the examples, which is due to the low sulfur content of the mixture in Comparative Examples 1-3; Comparative Example 4 has a multi-benzene ring structure, so its refractive index is the smallest.

[0211] The transmittances of Examples 1-6 and Comparative Examples 1-4 are both greater than 90%, indicating that the structures 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 have high transmittance.

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

[0213] In Examples 1-6, there are no particles on the surface of the microstructures, and the surface molecules are well demolded. In Comparative Examples 1-3, the microstructures have particles, and the lack of long-chain sulfanyl structures on the surface has an adverse effect on demolding. Comparative Example 4 has cracks on the surface, which may be due to the rigid fluorene groups in the molecular chain making the material prone to stress accumulation during the nanoimprint crosslinking and curing process, and the stress develops into cracks during demolding.

[0214] As shown in Table 1, the microstructure height, width, and period average values ​​of Examples 1-6 and Comparative Examples 1-3 are within the design value range. Fig.13 As shown, it is shown that the resin mixture prepared by the compounds of the structural formula A-1, A-2, A-3, A-4, A-5, and A-6 in the present invention has good shape retention performance, can well replicate the pattern on the template, and the height of the pattern after nanoimprinting is between 70nm and 90nm, and the width is between 140nm and 160nm. The structure of the present invention also contains the three benzothiocyclic structures of the structural formula B-1, B-2, and B-3. Comparative Example 4 is a sulfur-free structure. The micro-nano structure of the resin mixture without sulfur structure deviates from the design value more than the micro-nano period, indicating that the high sulfur content is conducive to the packaging of the micro-nano structure.

[0215] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. An optical monomer with a high refractive index, characterized in that: It includes at least one set of hybrid units and two polysulfide chains respectively located at the two end chains of the hybrid units; The hybrid unit includes three benzosulfide rings connected via sulfur, and each of the benzosulfide rings includes a benzene ring and two cyclohexyldisulfanyl groups hybridly connected to the benzene ring.

2. The optical monomer with high refractive index according to claim 1, characterized in that: The polysulfide chain includes at least three connected sulfurs; and / or the polysulfide chain is connected with an unsaturated functional group.

3. The optical monomer with high refractive index according to claim 2, characterized in that: The optical monomer has the following general structural formula (I): Among them, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 Each is H or 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 One of an arylalkylene group and a fluoroalkyl group; R 13 , R 14 Each of them is H or methyl; n1, n2, n3 are positive integers of 1 to 50.

4. The optical monomer with high refractive index according to claim 3, characterized in that: n1, n2, n3 are 1 respectively, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 They are H, R 13 , R 14 Each is H or methyl; The structural formula of the optical monomer is as follows (A-1) or (A-2): or, 5. The optical monomer with high refractive index according to claim 3, characterized in that: n1, n2, n3 are 1 respectively, R1, R3, R5, R7, R9, R 11 Each of them is phenyl, R2, R4, R6, R8, R 10 , R 12 They are H; R 13 , R 14 Each is H or methyl; The structural formula of the optical monomer is as follows (A-3) or (A-4): or, 6. The optical monomer with high refractive index according to claim 3, characterized in that: n1, n2, n3 are 1 respectively, R1, R3, R5, R7, R9, R 11 Each of them is methyl, R2, R4, R6, R8, R 10 , R 12 They are H; R 13 , R 14 Each is H or methyl; the structural formula of the optical monomer is as follows (A-5) or (A-6): or, 7. A resin mixture, characterized in that: The resin mixture includes the following components in weight percentage: Solvent 10%~79%; 10% to 79% of the optical monomer with a high refractive index as described in any one of claims 1 to 6; Diluent 10% to 50%; Photoinitiator 0.1% to 10%; Leveling agent 0.1%~5%; Silane coupling agent 0.1%~5%.

8. The resin mixture according to claim 7, characterized in that The solvent is at least one of propylene glycol methyl ether acetate, ethyl acetate, dichloromethane, ethanol, isopropanol, butyl acetate, butyl acetate, tetrahydrofuran, dimethyl sulfoxide, N,N-dimethylformamide, tetramethylethylenediamine, and carbon tetrachloride.

9. The resin mixture according to claim 7, characterized in that The diluent is at least one of propylene glycol methyl ether acetate, EM2206, and 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene.

10. The resin mixture according to claim 7, characterized in that The absorption wavelength of the photoinitiator is 368nm to 420nm; and / or, The photoinitiator is acylphosphine oxide, 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-carboxyl-2-methyl ester, diethoxyacetophenone, 4-tert-butyltrichloroacetophenone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2-dimethylaminoethyl benzoate, 4,6-trimethylbenzoyldimethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, benzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiethoxyphenylphosphine oxide, benzoyldiethoxyphosphine oxide, benzophenone and its derivatives, benzil and its derivatives, anthraquinone and its derivatives, benzoin, benzoin methyl ether, At least one of benzoin ethyl ether, benzoin propyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, p-dimethylaminoethyl benzoate, 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-13-yl]-2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, α-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.

11. The resin mixture according to claim 7, characterized in that The leveling agent is one of BYK331, BYK370, BYK3505 and BYK348.

12. The resin mixture according to claim 7, characterized in that The silane coupling agent is one of KH570, KH550 and KH560.

13. The resin mixture according to any one of claims 7 to 12, characterized in that The refractive index of the resin mixture is greater than 1.

73.

14. Use of the resin mixture according to any one of claims 7 to 13, characterized in that: The resin mixture is used for nanoimprinting.

15. A method for preparing an optical monomer with a high refractive index, characterized in that: At least the following steps are included: The first monomer and the second monomer are reacted in the presence of ethanol and sodium ethoxide, and a compound including a benzothiocyclic group is obtained as a first product through extraction, solvent removal and purification. processing the first product to generate a second product; reacting the second product with the first product in the presence of ethanol and sodium ethoxide to generate a compound having a hybrid unit as a third product; The third product is reacted with a third monomer to generate a compound having a plurality of sulfur hybrid units connected to both end chains as a fourth product; The fourth product is reacted with a fourth monomer to generate an optical monomer with a high refractive index.

16. The method for preparing a high refractive index optical monomer according to claim 15, characterized in that: The structural formula of the first monomer is: and / or, The structural formula of the second monomer is and / or, The structural formula of the third monomer is: and / or, The structural formula of the fourth monomer is:

17. The method for preparing a high refractive index optical monomer according to claim 15, characterized in that: The first product is processed to generate the second product, which includes: the first product is stirred and refluxed at 100° C. to 110° C. for 7 h to 9 h in the presence of toluene solution, sodium hydrosulfide solution, and tetrabutylammonium bromide to generate the second product.

18. The method for preparing a high refractive index optical monomer according to claim 16, characterized in that: It also includes the structural formula The reactants are stirred and refluxed at 55°C to 65°C for 3h to 5h in the presence of toluene solution, sodium hydrosulfide solution and tetrabutylammonium bromide to generate a product having the structural formula The first monomer.

19. The method for preparing a high refractive index optical monomer according to claim 16, characterized in that: The third product is reacted with the third monomer to generate a compound having a plurality of sulfur hybrid units connected to both end chains, wherein the reaction conditions include: adding the third monomer and the third product in sequence and stirring at 0°C and in a nitrogen atmosphere, reacting with stirring at room temperature for 32h to 40h, and obtaining a fourth product after extraction, drying, removing the solvent, and purification.

20. The method for preparing a high refractive index optical monomer according to claim 16, characterized in that: The reaction conditions for reacting 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 the presence of dichloromethane solvent and triethylamine for 15 hours to 20 hours.

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