A high refractive index precursor liquid, preparation method and application thereof

Abstract

The present invention discloses a high refractive index precursor liquid, a preparation method and its application, which comprises the following specific raw materials in parts by weight: 1 to 10 parts by weight of nano-inorganic particles, 5 to 10 parts by weight of resin monomer, 1 to 5 parts by weight of additive, 1 to 5 parts by weight of surfactant, 1 to 5 parts by weight of initiator and 65 to 100 parts by weight of solvent; wherein, the nano-inorganic particles used are products obtained after ligand modification. The high refractive index precursor liquid prepared by the present invention reduces the curing shrinkage while taking into account the transmittance and haze, prevents the occurrence of surface warping, and has a visual range greater than 110°, plays a role in scattering the bottom blue light, so that the RGB effect can still be achieved after removing the color filter, has excellent light diffusion effect, solves the problem of low blue light scattering degree in the "blue light + CCM method" of the prior art OLED device, effectively reduces the cost and extends the service life of the device.

Description

Technical Field

[0001] This invention belongs to the field of fine chemical technology, specifically relating to a high refractive index precursor liquid, its preparation method, and its application. Background Technology

[0002] OLED stands for Organic Light-Emitting Diode. It is a type of LED. Compared with the currently widely used flat panel displays (LCDs), OLEDs have many advantages, including self-emissive display, low driving voltage, high luminous efficiency, short response time, high clarity and contrast, near 180° viewing angle, wide operating temperature range, and the ability to achieve flexible displays and large-area full-color displays. It is widely recognized in the industry as the display device with the greatest development potential.

[0003] Current colorization solutions mainly include the RGB three-color emission method, the color conversion method based on blue light materials, and the method using a white light emitting layer with color filters. Each of these three methods has its own advantages and disadvantages. How to obtain high-volume, high-yield, low-cost, and long-life color OLED products has become a global research focus. Currently, the RGB three-color method is the main way to achieve color, while the blue light + CCM (color correction matrix) method and the white light + CF (color filter) method are technologies with great development potential. At the same time, the lifespan of the materials and the consistency of brightness decay of the emitting materials are also problems that need to be solved to achieve colorization.

[0004] Among these methods, the blue light + CCM method has garnered significant attention. It utilizes blue light irradiating the color conversion layer at the bottom layer to excite the material into emitting red and green light. Blue light is emitted in two ways: one is by using a blue filter, and the other is by directly extracting the blue light from the bottom layer without a filter. The second method, which avoids filters, not only reduces costs but also allows for better thinning, thus attracting more attention. However, because red and green light are excited and emitted, their scattering effect is more pronounced, while blue light, being directly extracted, is not scattered. Looking down from the top layer, the pixels of red and green light are significantly larger than those of blue light, leading to color difference during imaging and reduced light extraction efficiency. Therefore, improving the scattering degree of blue light in the "blue light + CCM method" has become an urgent problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and propose a high refractive index precursor liquid, its preparation method and its application. The high refractive index precursor liquid is formed by compounding a variety of specific raw materials in a set ratio. In particular, it uses nano-inorganic particles that have been modified by ligands. This allows the precursor liquid to reduce the curing shrinkage rate while taking into account both transmittance and haze, preventing surface warping. Moreover, the visible range is greater than 110°, which can scatter the blue light at the bottom layer and achieve RGB effect even after removing the color filter, thus having excellent light diffusion effect.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a high refractive index precursor liquid, comprising, by weight, the following raw materials: 1 to 10 parts by weight of nano-inorganic particles, 5 to 10 parts by weight of resin monomer, 1 to 5 parts by weight of additive, 1 to 5 parts by weight of surfactant, 1 to 5 parts by weight of initiator and 65 to 100 parts by weight of solvent.

[0008] The nano-inorganic particles are products obtained after ligand modification.

[0009] Furthermore, the ligand modification process consists of the following two steps:

[0010] The first step is to remove impurities and activate the surface of the nano-inorganic particles by using dilute hydrochloric acid or dilute nitric acid, which is used to change the double electron layer structure on the nano-inorganic particles (which is beneficial for subsequent ligand modification).

[0011] The second step involves using acrylate or silane coupling agents to modify the nano-inorganic particles treated in the first step with ligands.

[0012] Preferably, the silane coupling agent can be one or more alkoxysilane compounds selected from decyltrimethoxysilane, decyltriethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, etc.; and / or

[0013] One or more of the following silane compounds having sulfur-containing functional groups: 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis(triethoxysilylpropyl)tetrasulfide, etc.

[0014] Existing methods can be used when surface-modifying inorganic particles using silane coupling agents. Specifically, a silane coupling agent can be added to the inorganic particle dispersion, and stirring can be performed under predetermined temperature, predetermined time, and predetermined pressure conditions. The surface-modified inorganic particle dispersion is used directly when manufacturing the dispersion of the present invention.

[0015] Furthermore, the nano-inorganic particles are one or more selected from ZrO2, ZnO, TiO2, ZnS, ZnSe, and diamond, and the average particle size of the nano-inorganic particles is 1 nm to 50 nm, with each type of nano-inorganic particle having a refractive index greater than 1.9. This is because if the particle size is less than 1 nm, the particle size is too small, making it difficult to increase the refractive index; conversely, if the particle size exceeds 50 nm, the particle size is too large, tending to reduce dispersibility and decrease the optical properties of the composition or cured product.

[0016] Further, the resin monomer includes one or more of 2-acetylated bisphenol A diacrylate, 3-acetylated bisphenol A diacrylate, 4-acetylated bisphenol A diacrylate, 10-acetylated bisphenol A diacrylate, ethoxylated bisphenol A diacrylate, acetylated bisphenol A dimethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexaacrylate, ditrimethylolpropane tetraacrylate, and trimethylolpropane tetraacrylate.

[0017] Preferably, the resin monomer contains an aromatic ring, which can reduce surface tension. The product models purchased from Changxing Resin Co., Ltd. are as follows: EM2260, EM2261, EM2263, EM2265, EM2269, EM3261, EM3262, EM263, and EM267.

[0018] Furthermore, the additive is a silicone surface aid, specifically a structured acrylic copolymer solution containing pigment-affinity groups. It is purchased from BYK Chemicals and includes one or more of the following models: BYK-22543, BYK-22102, BYK-2000, and BYK-2001.

[0019] Furthermore, the surfactant is a polyether-modified polydimethylsiloxane solution. It is one or more of the following products purchased from BYK Chemicals: BYK-300, BYK-302, BYK-306, and BYK-320.

[0020] Furthermore, the initiator is an acylphosphine oxide photoinitiator, selected from one or more of TPO (diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide), TPO-L, and 819.

[0021] Further, the solvent is one or more of xylene, naphtha, n-hexane, isohexane, cyclohexane, methylcyclohexane, acetone, MEK (methyl ethyl ketone), methyl isobutyl ketone, DIBK (diisobutyl ketone), cyclohexanone, DAA (diacetone alcohol), ethyl acetate, butyl acetate, methoxybutyl acetate, ethylene glycol monomethyl ether acetate, PGMEA (propylene glycol monomethyl ether acetate), diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, amyl acetate, n-propyl acetate, isopropyl acetate, methyl lactate, ethyl lactate, butyl lactate, DMF (N,N-dimethylformamide), DEF (N,N-diethylformamide), DMAc (N,N-dimethylacetamide), and NMP (N-methylpyrrolidone).

[0022] Preferably, the solvent is DAA or PGMEA.

[0023] Secondly, the present invention also provides a method for preparing the above-mentioned high refractive index precursor liquid, which is based on the above raw materials and proportions, and specifically includes the following steps:

[0024] Step 1: Dissolve the ligand-modified nano-inorganic particles in a solvent, stir for 1 to 3 hours, and then centrifuge to obtain a high-refractive-index dispersion. During centrifugation, nano-inorganic particles with poor ligand modification, uneven dispersion, or agglomeration should be removed.

[0025] Step 2: Add the remaining raw materials to the high refractive index dispersion obtained in Step 1 according to the weight ratio, and stir for 0.5h to 2h to obtain the target product high refractive index precursor liquid.

[0026] Thirdly, the present invention also provides an application of the above-mentioned high refractive index precursor liquid, which can be used to prepare luminescent materials, specifically in the RGB layer of OLED display devices, to achieve the effect of scattering blue light after removing the CF layer.

[0027] In this invention, a high-refractive-index precursor liquid is introduced onto the blue light color conversion layer. After curing, it achieves a lens-like scattering effect, making the pixel size of blue light similar to that of green and red light. This effectively eliminates color difference and also allows for effective device thinning. In other words, this invention addresses the problem of low blue light scattering in existing OLED devices using the "blue light + CCM method." By introducing a high-refractive-index precursor liquid to form a scattering layer of a microlens array, it achieves RGB effects even without the color filter (CF), while effectively reducing costs, improving light extraction efficiency, and extending device lifespan.

[0028] Furthermore, this invention also discloses an inorganic EL device, comprising: at least two electrodes, and a light-emitting layer composed of the luminescent material of this invention and disposed between the electrodes. Inorganic EL devices prepared using the high-refractive-index precursor liquid of this invention as a raw material for producing the luminescent material can improve emission efficiency through the composition of their materials.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The high refractive index precursor liquid provided by this invention is formed by compounding multiple specific raw materials in a set proportion. Specifically, the raw materials used include nano-inorganic particles, resin monomers, additives, surfactants, initiators, and solvents. In particular, the nano-inorganic particles used are products obtained after ligand modification treatment, which allows these nano-inorganic particles to maintain a certain haze while also possessing good compatibility with organic solvents, enabling them to be effectively dispersed in the solution without rapid sedimentation leading to phase separation. Therefore, the precursor liquid finally obtained by this invention not only has a high refractive index but also good stability.

[0031] 2. The high refractive index precursor liquid provided by this invention, when used in the full-color inorganic EL device structure of OLEDs, can form a scattering layer of the microlens array. This scatters the underlying blue light, matching the brightness and size of the blue pixels with the red and green light, while still achieving RGB effects even after removing the color filter (CF). Furthermore, it allows for effective device thinning. Therefore, it can effectively reduce costs, improve light extraction efficiency, and extend the device's lifespan. Detailed Implementation

[0032] Exemplary embodiments will now be described in detail. The embodiments described below are not representative of all embodiments consistent with this invention. Rather, they are merely examples consistent with some aspects of the invention as detailed in the appended claims.

[0033] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to embodiments.

[0034] Example 1

[0035] In this embodiment, the raw materials used in preparing the high refractive index precursor liquid include, by weight, 2 parts of nano-inorganic particles, 5 parts of resin monomer, 2 parts of additive, 3 parts of surfactant, 3 parts of initiator, and 85 parts of solvent.

[0036] In this embodiment, the inorganic nanoparticles used are products obtained by ligand modification of ZrO2 inorganic nanoparticles. The specific ligand modification process consists of the following two steps: first, ZrO2 inorganic nanoparticles are treated with dilute hydrochloric acid to remove impurities and activate them; then, phenyltrimethoxysilane is added and stirred to obtain ligand-modified inorganic nanoparticles.

[0037] The resin monomer was purchased from Changxing Resin Co., Ltd. (model EM2260), the additive was purchased from BYK Chemical (model BYK-22543), the surfactant was purchased from BYK Chemical (model BYK-300), the initiator was TPO, and the solvent was PGMEA.

[0038] The preparation method includes the following steps:

[0039] 1) The ligand-modified nano-inorganic particles were dissolved in PGMEA solvent, stirred for 1 h, and then centrifuged to obtain a high refractive index dispersion;

[0040] 2) Add the remaining components (resin monomer EM2260, additive BYK-22543, surfactant BYK-300 and initiator TPO) to the high refractive index dispersion obtained in step 1) according to the weight ratio, and stir for 0.5 h to obtain the target product (high refractive index precursor liquid).

[0041] Example 2

[0042] In this embodiment, the raw materials used in preparing the high refractive index precursor liquid include, by weight, 5 parts of nano-inorganic particles, 6 parts of resin monomer, 3 parts of additive, 4 parts of surfactant, 4 parts of initiator, and 78 parts of solvent.

[0043] In this embodiment, the nano-inorganic particles used are products obtained by modifying ZrO2 nano-inorganic particles with ligands. The specific ligand modification method is the same as in Example 1 and will not be repeated here.

[0044] The resin monomer was purchased from Changxing Resin Co., Ltd. (product model EM2263), the additive was purchased from BYK Chemical (model BYK-22102), the surfactant was purchased from BYK Chemical (model BYK-302), the initiator was TPO, and the solvent was PGMEA.

[0045] The preparation method includes the following steps:

[0046] 1) The ligand-modified nano-inorganic particles were dissolved in PGMEA solvent, stirred for 1.5 h, and then centrifuged to obtain a high refractive index dispersion;

[0047] 2) Add the remaining components (resin monomer EM2263, additive BYK-22102, surfactant BYK-302 and initiator TPO) to the high refractive index dispersion obtained in step 1) according to the weight ratio, and stir for 0.5 h to obtain the target product (high refractive index precursor liquid).

[0048] Example 3

[0049] In this embodiment, the raw materials used in preparing the high refractive index precursor liquid include, by weight, 8 parts of nano-inorganic particles, 8 parts of resin monomer, 4 parts of additive, 5 parts of surfactant, 5 parts of initiator, and 70 parts of solvent.

[0050] In this embodiment, the nano-inorganic particles used are products obtained by modifying ZrO2 nano-inorganic particles with ligands. The specific ligand modification method is the same as in Example 1 and will not be repeated here.

[0051] The resin monomer was purchased from Changxing Resin Co., Ltd. (product model EM2265), the additive was purchased from BYK Chemical (model BYK-2000), the surfactant was purchased from BYK Chemical (model BYK-306), the initiator was TPO-L, and the solvent was DAA.

[0052] The preparation method includes the following steps:

[0053] 1) The ligand-modified nano-inorganic particles were dissolved in DAA solvent, stirred for 1.5 h, and then centrifuged to obtain a high refractive index dispersion;

[0054] 2) Add the remaining components (resin monomer EM2265, additive BYK-2000, surfactant BYK-306 and initiator TPO-L) to the high refractive index dispersion obtained in step 1) according to the weight ratio, stir for 1 hour, and the target product (high refractive index precursor liquid) can be obtained.

[0055] Example 4

[0056] In this embodiment, the raw materials used in preparing the high refractive index precursor liquid include, by weight, 10 parts of nano-inorganic particles, 10 parts of resin monomer, 5 parts of additives, 2 parts of surfactant, 3 parts of initiator, and 70 parts of solvent.

[0057] In this embodiment, the nano-inorganic particles used are products obtained by modifying ZrO2 nano-inorganic particles with ligands. The specific ligand modification method is the same as in Example 1 and will not be repeated here.

[0058] The resin monomer was purchased from Changxing Resin Co., Ltd. (product model EM3261), the additive was purchased from BYK Chemical (model BYK-2001), the surfactant was purchased from BYK Chemical (model BYK-320), the initiator was 819, and the solvent was DAA.

[0059] The preparation method includes the following steps:

[0060] 1) The ligand-modified nano-inorganic particles were dissolved in DAA solvent, stirred for 2 hours, and then centrifuged to obtain a high refractive index dispersion;

[0061] 2) Add the remaining components (resin monomer EM3261, additive BYK-2001, surfactant BYK-320 and initiator 819) to the high refractive index dispersion obtained in step 1) according to the weight ratio, stir for 1.5h, and the target product (high refractive index precursor liquid) can be obtained.

[0062] Example 5

[0063] In this embodiment, the raw materials used in preparing the high refractive index precursor liquid include, by weight, 10 parts of nano-inorganic particles, 5 parts of resin monomer, 3 parts of additive, 3 parts of surfactant, 3 parts of initiator, and 76 parts of solvent.

[0064] In this embodiment, the nano-inorganic particles used are products obtained by modifying ZrO2 nano-inorganic particles with ligands. The specific ligand modification method is the same as in Example 1 and will not be repeated here.

[0065] The resin monomer was purchased from Changxing Resin Co., Ltd. (product model EM263), the additive was purchased from BYK Chemical (model BYK-2001), the surfactant was purchased from BYK Chemical (model BYK-320), the initiator was 819, and the solvent was DAA.

[0066] The preparation method includes the following steps:

[0067] 1) The ligand-modified nano-inorganic particles were dissolved in DAA solvent, stirred for 3 hours, and then centrifuged to obtain a high refractive index dispersion;

[0068] 2) Add the remaining components (resin monomer EM263, additive BYK-2001, surfactant BYK-320 and initiator 819) to the high refractive index dispersion obtained in step 1) according to the weight ratio, stir for 2 hours, and the target product (high refractive index precursor liquid) can be obtained.

[0069] Comparative Example 1

[0070] The only difference between this comparative example and Example 1 is that the nano-inorganic particles used in this comparative example have not undergone ligand modification treatment.

[0071] Comparative Example 2

[0072] The only difference between this comparative example and Example 1 is that the resin monomer used in this comparative example is phosphate methacrylate.

[0073] Comparative Example 3

[0074] The only difference between this comparative example and Example 1 is that the raw materials used in this comparative example, by weight, include 10 parts by weight of nano-inorganic particles, 15 parts by weight of resin monomer, 3 parts by weight of additive, 2 parts by weight of surfactant, 5 parts by weight of initiator, and 65 parts by weight of solvent. That is, this comparative example contains an excess of resin monomer.

[0075] Comparative Example 4

[0076] The only difference between this comparative example and Example 1 is that the raw materials used in this comparative example, by weight, include 15 parts by weight of nano-inorganic particles, 10 parts by weight of resin monomer, 2 parts by weight of additives, 3 parts by weight of surfactant, 5 parts by weight of initiator, and 65 parts by weight of solvent. That is, this comparative example contains an excessive amount of nano-inorganic particles.

[0077] To further verify the efficacy of the high refractive index precursor liquid of the present invention, the inventors conducted relevant tests on the performance of the high refractive index precursor liquids prepared in Examples 1-5 and Comparative Examples 1-4, specifically including the following aspects:

[0078] 1. Viscosity: The viscosity of the high-refractive-index precursor liquid was tested using a rotational rheometer (EVO type rotational viscometer) at 25°C. A 20mm diameter conical rotor was used for the test, and the shear rate was set to 0.01–500 s⁻¹. -1 And select 10s -1 The viscosity of the samples was compared at different shear rates. Each sample was tested five times, and the final data were averaged.

[0079] 2. Surface tension: The surface tension was tested using a surface tension meter (QBZY-2 type surface tension meter). The test was conducted at 25℃. Before the test, the sample was defoamed and centrifuged. Each sample was tested 5 times, and the final data was the average value.

[0080] 3. Haze: The haze of the cured high refractive index precursor liquid at a wavelength of 600 nm was measured using a BYK haze meter.

[0081] 4. Curing shrinkage rate: The high refractive index precursor liquid is inkjet printed onto the glass substrate at 30mW / cm². 2 The sample was then subjected to UV curing by UV irradiation to produce a sample with dimensions of 5mm × 3cm × 1mm (width × length × thickness).

[0082] Curing shrinkage rate (%) = (Vb-Va) / Vb×100%;

[0083] Where Vb is the volume before curing and Va is the volume after curing.

[0084] Curing shrinkage reflects the volume collapse change of the high refractive index precursor liquid before and after curing. The greater the curing shrinkage, the greater the collapse of the film formation and the worse the film formation effect.

[0085] 5. Visible range: The visible range is calculated by measuring the spot of the blue light from the bottom layer projected onto the plane of the high refractive index precursor liquid photocurable film and the distance between the blue light from the bottom layer and the plane of the photocurable film.

[0086] 6. Adhesion: The adhesion is tested using the cross-cut adhesion test. First, use a cross-cut adhesion tester to evenly cut squares of a certain size on the film layer of the test sample. Then, use 3M tape to pull the film layer apart. The degree of adhesion of the film layer to the substrate is evaluated by assessing the integrity of the film layer within the squares (refer to GB9286-1998).

[0087] Specifically, the ASTM grades are as follows:

[0088] 5B – The cut edges are smooth, and there is no peeling at the edges of the grid.

[0089] 4B — The area of ​​peeling within the gridded area is ≤5%;

[0090] 3B – The area of ​​peeling within the gridded area is greater than 5% to 15%;

[0091] 2B – The area of ​​peeling within the gridded area is greater than 15% to 35%;

[0092] 1B – The area of ​​peeling within the gridded area is greater than 35% to 65%;

[0093] 0B – The peeling area within the gridded area is greater than 65%.

[0094] 7. Transmittance: A high-refractive-index precursor liquid was used to form a sample via inkjet printing, followed by UV curing to form a photocurable film. The transmittance of the cured film in the visible light range of 400–700 nm was measured using a UV spectrophotometer.

[0095] Based on the above evaluation methods, the results of optical viscosity, surface tension, light transmittance, haze, curing shrinkage, visible range and adhesion of the high refractive index precursor liquids prepared in Examples 1 to 5 and Comparative Examples 1 to 4 of the present invention are detailed in Table 1 below.

[0096] Table 1

[0097]

[0098] The transmittance of the photocurable film represents the overall utilization rate of incident light, while haze represents the degree to which incident light deviates from its original incident direction. Therefore, transmittance and haze characterize the degree of diffusion of incident light introduced by the photocurable film. An increase in haze leads to a decrease in transmittance.

[0099] As shown in Table 1, the high refractive index precursor liquids prepared in Examples 1-5 of this invention have a viscosity of approximately 3 cPs to 3.6 cPs, a surface tension of approximately 28 mN / m to 29 mN / m, a light transmittance of approximately 92% to 94.5%, a haze of approximately 2% to 4.5%, a curing shrinkage rate of approximately 3% to 4.5%, a visible range of approximately 110° to 120°, and an adhesion of 1B to 3B. Compared to the comparative example, the high refractive index precursor liquid system prepared in the examples of this invention has better visible range, adhesion, and curing shrinkage rate. It has a wider visible range, effectively scattering the blue light at the bottom layer, matching the brightness and size of the blue light pixels with the red and green light, and achieving RGB effect even after removing the color filter (CF).

[0100] Specifically, the inorganic nanoparticles in Comparative Example 1, without ligand modification, resulted in high transmittance, narrow visibility, and low adhesion when added to the system, negatively impacting the final product performance. The raw materials or proportions of Comparative Examples 2-4 differed from those claimed in this invention, leading to high-refractive-index precursor liquids with inferior adhesion compared to the examples. Furthermore, the visible range calculations failed to achieve the objectives of this invention and did not resolve the existing technical problem of a small blue light scattering angle at the bottom layer, thus failing to achieve the RGB effect. Additionally, the comparative examples exhibited high curing shrinkage, making surface warping more likely.

[0101] In summary, this invention, based on a specific formulation, selects specific resin monomers, additives, surfactants, solvents, and ligand-modified nano-inorganic particles as raw materials. The resulting high-refractive-index precursor liquid, while balancing transmittance and haze, reduces curing shrinkage, prevents surface warping, and has a visible range greater than 110°. It effectively scatters blue light from the underlying layer, achieving RGB effects even after removing the color filter, exhibiting excellent light diffusion and good adhesion. Furthermore, exposure energy was measured using a UV energy meter; the exposure energy results in this embodiment ranged from 40 to 100 mJ / cm². 2 At an exposure energy of 40 mJ / cm 2 At that time, the curing rate of the embodiments was all above 98%, while that of the comparative examples was above 98% at an exposure energy of 40 mJ / cm². 2 The curing rate was less than 60% at all times, indicating that the high refractive index precursor liquid of the present invention requires less energy to cure, has higher light utilization, low energy consumption, and low equipment requirements, which is more conducive to achieving the goal of green factory.

[0102] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention.

[0103] It should be understood that the present invention is not limited to the content already described above, and various modifications and changes can be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A high refractive index precursor liquid, characterized in that, By weight, it includes the following raw materials: 1 to 10 parts by weight of nano-inorganic particles, 5 to 10 parts by weight of resin monomer, 1 to 5 parts by weight of additives, 1 to 5 parts by weight of surfactant, 1 to 5 parts by weight of initiator and 65 to 100 parts by weight of solvent. The nano-inorganic particles are products obtained after ligand modification. The ligand modification process consists of the following two steps: The first step is to remove impurities and activate the surface of the nano-inorganic particles by using dilute hydrochloric acid or dilute nitric acid. The second step involves using acrylate or silane coupling agents to modify the nano-inorganic particles treated in the first step with ligands. The refractive index of the nano-inorganic particles is greater than 1.9, and the average particle size is 1 nm to 50 nm. The resin monomers include one or more of the following: 2-acetylated bisphenol A diacrylate, 3-acetylated bisphenol A diacrylate, 4-acetylated bisphenol A diacrylate, 10-acetylated bisphenol A diacrylate, ethoxylated bisphenol A diacrylate, acetylated bisphenol A dimethacrylate, dipentaerythritol hexaacrylate, di(trimethylolpropane)tetraacrylate, and trimethylolpropanetetraacrylate. The high refractive index precursor liquid has a curing shrinkage rate of 3.0-4.5% and a visible range of more than 110°. It is used in the RGB layer of OLED display devices to remove the CF layer and achieve a blue light scattering effect.

2. The high refractive index precursor liquid according to claim 1, characterized in that, The nano-inorganic particles are one or more of ZrO2, ZnO, TiO2, ZnS, ZnSe and diamond.

3. The high refractive index precursor liquid according to claim 1, characterized in that, The additive is a structured acrylic copolymer solution containing pigment affinity groups.

4. The high refractive index precursor liquid according to claim 1, characterized in that, The surfactant is a polyether-modified polydimethylsiloxane solution.

5. The high refractive index precursor liquid according to claim 1, characterized in that, The initiator is an acylphosphine oxide photoinitiator.

6. The high refractive index precursor liquid according to claim 1, characterized in that, The solvent is one or more selected from xylene, naphtha, n-hexane, isohexane, cyclohexane, methylcyclohexane, acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclohexanone, diacetone alcohol, ethyl acetate, butyl acetate, methoxybutyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, amyl acetate, n-propyl acetate, isopropyl acetate, methyl lactate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

7. A method for preparing a high refractive index precursor liquid according to any one of claims 1 to 6, characterized in that, Specifically, the following steps are included: Step 1: Dissolve the ligand-modified nano-inorganic particles in a solvent, stir for 1-3 hours, and then centrifuge to obtain a high-refractive-index dispersion. Step 2: Add the remaining raw materials to the high refractive index dispersion obtained in Step 1 according to the weight ratio, and stir for 0.5h to 2h to obtain the target product high refractive index precursor liquid.

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