Modified phenolic resin with dual photo-thermal curing properties, its preparation method and application

Abstract

The present invention relates to the field of lithography technology, and in particular to a modified phenolic resin having both photo-thermal dual curing properties, a preparation method thereof, and an application thereof. The modified phenolic resin of the present invention has both double bonds and epoxy groups, and can achieve rapid curing through a photoreaction with a polythiol compound to achieve the lithography target. Moreover, the epoxy groups can undergo a thermal crosslinking reaction with polyamine substances added in the lithography system, further increasing the crosslinking density of the phenolic resin matrix in the post-baking stage, and can effectively improve the stability of the in-situ generated perovskite quantum dots under continuous light illumination. As a photoresist material for in-situ preparation of perovskite quantum dots, the modified phenolic resin can improve problems such as easy agglomeration of quantum dots in the polymer matrix and easy detachment of ligands, and improve the stability of perovskite quantum dots and the devices prepared therefrom.

Description

Technical Field

[0001] The present invention relates to the field of lithography technology, and particularly to a modified phenolic resin having photo-thermal dual-curing properties, a preparation method thereof, and an application thereof. Background Art

[0002] Perovskite materials have excellent light trapping and light emission properties and are widely used in fields such as solar cells, photodetectors, lighting displays, etc. As a display material, perovskite quantum dots have the advantages of simple preparation process, high quantum efficiency, narrow emission band gap, wide color gamut, etc., and are attracting more and more attention from the scientific community and the business community. The manufacture of modern photonics and optoelectronic devices requires efficient and economical patterning processes. Currently, methods for patterning perovskite quantum dot materials include inkjet printing, laser direct writing, nanoimprinting, and direct lithography. Among them, lithography technology is one of the preferred methods for preparing future display materials due to its advantages such as high resolution, strong operability, and high throughput. Lithography technology uses ultraviolet light, electron beams, etc. to irradiate a photoresist, causing a change in its solubility in a developer, thereby achieving the patterning of perovskite quantum dots.

[0003] However, due to its strong ionic nature, high surface energy, and metastable structure, perovskite quantum dots are highly sensitive to the environment, which easily causes problems such as structural collapse, shape deformation, and rapid decline in quantum yield (QYs). Exposure of perovskite quantum dot materials to air will cause phase transformation, aggregation, and even degradation under the synergistic action of water and oxygen, resulting in luminescence quenching and further leading to a decrease in the efficiency of optoelectronic devices. In addition, traditional perovskite quantum dots use oleic acid and oleylamine as ligands during the preparation process. The ligands continuously adsorb and desorb on the surface of the quantum dots, and the chemical bond between oleylamine / oleic acid and the quantum dot surface is relatively weak, and it is easy to lose ligands during purification or use, resulting in aggregation and precipitation of perovskite quantum dots and a decrease in luminescence efficiency. Moreover, this ligand exchange will also cause rapid anion exchange when different halogen perovskite quantum dots come into contact, resulting in perovskite quantum dots with mixed halogen components and causing a shift in the emission wavelength.

[0004] Phenolic resin has advantages such as good stability, good insulation, mature synthesis process, and low cost, and is widely used in high-tech fields such as electronic packaging and aerospace. However, when existing phenolic resins are used for patterning perovskite quantum dot materials, the patterned perovskite quantum dots have problems of insufficient light stability.

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

[0006] An object of the present invention is to provide a modified phenolic resin having photo-thermal dual-curing performance. When used in a lithography system, a photo-curing reaction first occurs to form a pattern, and then further thermal curing occurs during the post-baking process to increase the network crosslinking density of the matrix, effectively improving the stability of the perovskite quantum dot pattern under continuous light irradiation.

[0007] Another object of the present invention is to provide a preparation method of a modified phenolic resin having photo-thermal dual-curing performance.

[0008] Still another object of the present invention is to provide an application of a modified phenolic resin having photo-thermal dual-curing performance in perovskite quantum dot patterning.

[0009] To achieve the above objects of the present invention, on the one hand, the present invention provides a modified phenolic resin having photo-thermal dual-curing performance, having at least one of the structures represented by the following general formula I or II:

[0010]

[0011]

[0012] Among them, a, b, c, and d are each independently selected from integers between 0 and 10, y is selected from integers between 1 and 5, and x satisfies: 0 < x / (x + a + b + c + d) ≤ 0.2;

[0013] R is selected from at least one of H and and e is selected from integers between 0 and 6.

[0014] In a specific embodiment of the present invention, x / (x + a + b + c + d) is 0.01 to 0.1.

[0015] In a specific embodiment of the present invention, a, b, c, and d are each independently selected from integers between 0 and 6; e is selected from integers between 0 and 4.

[0016] On the other hand, the present invention provides a preparation method of the modified phenolic resin having photo-thermal dual-curing performance as described in any one of the above, including the following steps:

[0017] Resin A reacts with epichlorohydrin in a solvent under the action of an organic base;

[0018] Among them, the resin A has at least one of the structures represented by the following general formula III or IV:

[0019]

[0020]

[0021] In a specific embodiment of the present invention, the molar ratio of the resin A based on its phenolic hydroxyl groups to the epichlorohydrin is 1:(0.1 - 0.2).

[0022] In a specific embodiment of the present invention, the organic base includes imidazole. Further, the molar ratio of the organic base to the epichlorohydrin is (1 - 2):1.

[0023] In a specific embodiment of the present invention, the temperature of the reaction is 60 - 80 °C, and the time of the reaction is 4 - 8 h.

[0024] On the other hand, the present invention provides a photoresist, comprising any one of the above-mentioned modified phenolic resins having photo-thermal dual-curing properties, a polythiol compound, a polyamine substance, a photoinitiator, and a solvent;

[0025] The molar ratio of the modified phenolic resin having photo-thermal dual-curing properties and the polyamine substance based on their epoxy groups and amino groups respectively is 1:(0.8 - 1.2).

[0026] In a specific embodiment of the present invention, the polyamine substance includes at least one of 1,3-diaminopropane, N-aminoethylpiperazine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, branched polyethyleneimine, 1,4-diaminobutane, 1,5-diaminopentane, N,N',N''-trimethyldiethylenetriamine, 4-chloro-o-phenylenediamine, p-aminophenethylamine, N-ethylpentylamine, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and 1,3-bis[3-[bis[3-[3-[3-(3-aminopropyl)-1,1,3,3-tetramethyldisiloxanyl]propyl]amino-3-oxopropyl]amino]propyl]-1,1,3,3-tetramethyldisiloxane.

[0027] In a specific embodiment of the present invention, the molar ratio of the modified phenolic resin having photo-thermal dual-curing properties based on its carbon-carbon double bonds to the sulfhydryl groups in the polythiol compound is 1:(0.5 - 2).

[0028] In a specific embodiment of the present invention, the polythiol compound includes at least one of 1,2-ethanedithiol, 2,3-butanedithiol, 1,3-propanedithiol, 1,4-butanedithiol, 1,4-butanediol bis(3-mercaptopropionate), 1,9-nonanedithiol, 3,6-dioxa-1,8-octanedithiol, 1,4-butanediol bis(mercaptoacetate), pentaerythritol tetra-3-mercaptopropionate, and trimethylolpropane tris(3-mercaptopropionate).

[0029] In a specific embodiment of the present invention, the solvent includes at least one of N-methylpyrrolidone, N,N-dimethylformamide, dimethyl sulfoxide, and acetonitrile.

[0030] In a specific embodiment of the present invention, the photoresist further includes a precursor for forming perovskite quantum dots.

[0031] Another aspect of the present invention provides a method for patterning perovskite quantum dots, comprising the following steps: disposing any one of the above-mentioned photoresists on a substrate, performing ultraviolet light exposure treatment under the coverage of a mask plate to in-situ generate perovskite quantum dots, and developing with a developer; then performing heat treatment at 80-120 °C for 0.5-2 h.

[0032] The present invention also provides a patterned perovskite quantum dot, which is prepared by using any one of the above-mentioned methods for patterning perovskite quantum dots.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] (1) The modified phenolic resin of the present invention has both double bonds and epoxy groups, and can be cured by a photoreaction with a poly-thiol compound to achieve photolithographic patterning. Moreover, the epoxy groups can undergo a thermal cross-linking reaction with polyamine substances added in the photolithographic system, further increasing the cross-linking density of the phenolic resin matrix during the post-baking process, effectively improving the stability of the perovskite quantum dot pattern under continuous light illumination;

[0035] (2) The modified phenolic resin with both photo-thermal dual-curing properties of the present invention, when used for preparing a photoresist, can be cross-linked and cured by both light and heat, and can in-situ generate perovskite quantum dots and effectively fix them and ligand luminescent units in a polymer cross-linked network system, thereby improving problems such as easy aggregation of quantum dots and easy detachment of ligands, and enhancing the stability of perovskite quantum dots and the devices prepared therefrom. Description of the Drawings

[0036] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0037] Figure 1 1H NMR spectra of different phenolic resins provided by the present invention;

[0038] Figure 2 13C NMR spectra of different phenolic resins provided by the present invention;

[0039] Figure 3 Blue light conversion comparison of the photoresists corresponding to different phenolic resins provided by the present invention after single photo-curing;

[0040] Figure 4 Comparison of blue light conversion after photothermal dual-curing of photoresists corresponding to different phenolic resins provided by the present invention;

[0041] Figure 5 Graph showing the change of power conversion efficiency (PCE) over time after aging of different photoresists provided by the present invention under continuous blue light illumination;

[0042] Figure 6 Graph showing the change of CIEy over time after aging of different photoresists provided by the present invention under continuous blue light illumination. Detailed implementation manners

[0043] The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific implementation manners. However, those skilled in the art will understand that the following described embodiments are some embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention. For those conditions not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. For those reagents or instruments without indicating the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0044] Existing patterned phenolic resins available for perovskite quantum dot materials have insufficient stability of the patterned perovskite quantum dots under long-term light illumination due to short lithography time and the attenuation characteristics of light waves.

[0045] Based on this, the present invention covalently grafts a certain amount of epoxy functional groups in a specific phenolic resin structure. The epoxy group can be used as a thermal curing functional group and undergoes a thermal cross-linking reaction with polyamine substances in the photoresist system during the post-baking stage, further increasing the cross-linking density and improving the stability of the perovskite quantum dot pattern; at the same time, ensuring that the introduction of the epoxy group and the introduction of polyamine substances in the system do not affect the in-situ generation of perovskite quantum dots and have no impact on patterning.

[0046] On the one hand, the present invention provides a modified phenolic resin with photo-thermal dual-curing performance, having at least one of the structures represented by the following general formula I or II:

[0047]

[0048] Wherein, a, b, c, and d are each independently selected from integers between 0 and 10, y is selected from integers between 1 and 5, and x satisfies: 0 < x / (x + a + b + c + d) ≤ 0.2;

[0049] R is selected from H and At least one of them, e is an integer between 0 and 6.

[0050] The modified phenolic resin of the present invention contains double bonds, siloxane segments and epoxy groups at the same time. The siloxane segments can provide a flexible part for the resin structure and regulate polarity; the double bonds can react with polythiol compounds through a photoreaction to achieve photocuring and complete the in-situ generation and patterning of perovskite, without generating small molecule by-products and without the catalysis of acids or bases, avoiding the damage to the perovskite quantum dot structure; at the same time, the epoxy groups can undergo a thermal cross-linking reaction with polyamine substances introduced into the photoresist system during the post-baking stage, further increasing the cross-linking density and improving the stability of the perovskite quantum dot pattern, and the introduction of epoxy groups and polyamine substances does not affect the in-situ generation of perovskite quantum dots, etc.

[0051] In different embodiments, a, b, c and d can each independently be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; y can be 1, 2, 3, 4 or 5; e can be 0, 1, 2, 3, 4, 5 or 6; x / (x + a + b + c + d) can be 0.01, 0.02, 0.05, 0.06, 0.08, 0.09, 0.1, 0.15, 0.2 or a range composed of any two of them.

[0052] In a specific embodiment of the present invention, x / (x + a + b + c + d) is 0.01 to 0.1. By regulating x / (x + a + b + c + d) within the above range, the modified phenolic resin can have an appropriate amount of epoxy groups, improving the stability of the perovskite quantum dots after patterning.

[0053] In a specific embodiment of the present invention, a, b, c and d are each independently selected from integers between 0 and 6; e is selected from integers between 0 and 4.

[0054] On the other hand, the present invention provides a preparation method of any of the above modified phenolic resins with photo-thermal dual-curing properties, including the following steps:

[0055] Resin A reacts with epichlorohydrin in a solvent under the action of an organic base;

[0056] Among them, Resin A has at least one of the structures represented by the following general formula III or IV:

[0057]

[0058]

[0059] The present invention may covalently graft a certain number of epoxy functional groups onto the modified phenolic resin with photo-thermal dual-curing properties by regulating the addition amount of epichlorohydrin to achieve the thermal curing function.

[0060] In a specific embodiment of the present invention, based on the phenolic hydroxyl groups in Resin A, the molar ratio of Resin A to epichlorohydrin is 1:(0.1 - 0.2).

[0061] In different embodiments, based on the phenolic hydroxyl groups in Resin A, the molar ratio of Resin A to epichlorohydrin can be 1:0.1, 1:0.12, 1:0.15, 1:0.18, 1:0.2, or a range composed of any two of them.

[0062] In a specific embodiment of the present invention, the organic base includes imidazole. Further, the molar ratio of the organic base to epichlorohydrin is (1 - 2):1.

[0063] In different embodiments, the molar ratio of the organic base to epichlorohydrin can be 1:1, 1.2:1, 1.4:1, 1.5:1, 1.6:1, 1.8:1, 2:1, or a range composed of any two of them.

[0064] In a specific embodiment of the present invention, the solvent includes at least one of dichloromethane, chloroform, and tetrahydrofuran. When there is a solvent in the system after the preparation of Resin A, it can be directly reacted with epichlorohydrin under corresponding conditions without the need to additionally add a solvent.

[0065] In a specific embodiment of the present invention, the reaction temperature is 60 - 80 °C, and the reaction time is 4 - 8 h.

[0066] In different embodiments, the reaction temperature can be 60 °C, 65 °C, 70 °C, 75 °C, 80 °C, or a range composed of any two of them, and the reaction time can be 4 h, 5 h, 6 h, 7 h, 8 h, or a range composed of any two of them. The specific reaction time is not limited thereto, and the reaction time can be adjusted according to the TLC monitoring of the reaction progress.

[0067] In a specific embodiment of the present invention, in the preparation of the modified phenolic resin with photo-thermal dual-curing properties, after the reaction, post-treatment is further included; the post-treatment includes: after the reaction, extraction is carried out with a solvent and water, the organic phase is collected, the solvent is removed, and the modified phenolic resin with photo-thermal dual-curing properties is obtained by drying.

[0068] In a specific embodiment of the present invention, the preparation of Resin A includes: allyl phenolic resin reacts with dimethyldichlorosilane in the presence of an organic base in a solvent;

[0069] Among them, the allyl phenolic resin has a general formula as shown in Formula V:

[0070]

[0071] f is an integer selected from 2 to 10.

[0072] In different embodiments, f can be 2, 3, 4, 5, 6, 7, 8, 9, 10, or a range composed of any two of them.

[0073] In a specific embodiment of the present invention, based on the phenolic hydroxyl groups in the allyl phenolic resin, the molar ratio of the allyl phenolic resin to dimethyldichlorosilane is (2 - 6):1.

[0074] In different embodiments, based on the phenolic hydroxyl groups in the allyl phenolic resin, the molar ratio of the allyl phenolic resin to dimethyldichlorosilane can be 2:1, 3:1, 4:1, 5:1, 6:1, or a range composed of any two of them.

[0075] In a specific embodiment of the present invention, in the preparation of resin A, the organic base includes imidazole. Further, the molar ratio of the organic base to dimethyldichlorosilane can be 1:1, 1.2:1, 1.4:1, 1.5:1, 1.6:1, 1.8:1, 2:1, or a range composed of any two of them.

[0076] In a specific embodiment of the present invention, in the preparation of resin A, the solvent includes at least one of dichloromethane, chloroform, and tetrahydrofuran.

[0077] In actual operation, in the preparation of resin A, the reaction of the allyl phenolic resin with dimethyldichlorosilane is carried out under a nitrogen, argon, or air atmosphere. The reaction can be carried out at room temperature, and the reaction time can be 10 - 14 h. Further, after the preparation of resin A is completed, no post-treatment is required, and the subsequent preparation of the modified phenolic resin with photo-thermal dual-curing properties can be directly carried out.

[0078] On the other hand, the present invention provides a photoresist, which includes any one of the above-mentioned modified phenolic resins with photo-thermal dual-curing properties, a polythiol compound, a polyamine substance, a photoinitiator, and a solvent;

[0079] Based on the epoxy groups and amino groups respectively, the molar ratio of the modified phenolic resin with photo-thermal dual-curing properties to the polyamine substance is 1:(0.8 - 1.2).

[0080] In different embodiments, based on the epoxy groups and amino groups respectively, the molar ratio of the modified phenolic resin with photo-thermal dual-curing properties to the polyamine substance can be 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, or a range composed of any two of them. By regulating the ratio of the modified phenolic resin with photo-thermal dual-curing properties to the polyamine substance within the above range, it is further ensured that without affecting the patterning of perovskite quantum dots, the stability of the perovskite quantum dot pattern is improved by thermal crosslinking.

[0081] In the specific embodiments of the present invention, the polyamine substances include at least one of 1,3-diaminopropane, N-aminoethylpiperazine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, branched polyethyleneimine, 1,4-diaminobutane, 1,5-diaminopentane, N,N',N”-trimethyldiethylenetriamine, 4-chloro-o-phenylenediamine, p-aminophenethylamine, N-ethylpentylamine, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and 1,3-bis[3-[bis[3-[3-[3-(3-aminopropyl)-1,1,3,3-tetramethyldisiloxanyl]propyl]amino-3-oxopropyl]amino]propyl]-1,1,3,3-tetramethyldisiloxane, and is preferably branched polyethyleneimine.

[0082] In the specific embodiments of the present invention, the molar ratio of the modified phenolic resin with photo-thermal dual-curing performance to the mercapto groups in the polythiol compound is 1﹕(0.5 - 2) based on the carbon-carbon double bonds therein.

[0083] In different embodiments, the molar ratio of the modified phenolic resin with photo-thermal dual-curing performance to the mercapto groups in the polythiol compound can be 1﹕0.5, 1﹕0.6, 1﹕0.8, 1﹕1, 1﹕1.2, 1﹕1.4, 1﹕1.5, 1﹕1.6, 1﹕1.8, 1﹕2, or the range composed of any two of them.

[0084] In the specific embodiments of the present invention, the polythiol compound includes at least one of 1,2-ethanedithiol, 2,3-butanedithiol, 1,3-propanedithiol, 1,4-butanedithiol, 1,4-butanediol bis(3-mercaptopropionate), 1,9-nonanedithiol, 3,6-dioxa-1,8-octanedithiol, 1,4-butanediol bis(mercaptoacetate), pentaerythritol tetra-3-mercaptopropionate, and trimethylolpropane tris(3-mercaptopropionate), and is preferably pentaerythritol tetra-3-mercaptopropionate (PTME).

[0085] In the specific embodiments of the present invention, the solvent includes at least one of N-methylpyrrolidone, N,N-dimethylformamide, dimethyl sulfoxide, and acetonitrile. Further, in the photoresist, the ratio of the modified phenolic resin with photo-thermal dual-curing performance to the solvent is (0.5 - 1) g﹕1 mL.

[0086] In different embodiments, the ratio of the modified phenolic resin with photo-thermal dual-curing performance to the solvent can be such that for every 1 mL of the solvent, the amount of the modified phenolic resin with photo-thermal dual-curing performance can be 0.5 g, 0.6 g, 0.7 g, 0.8 g, 0.9 g, 1 g, or the range composed of any two of them.

[0087] In a specific embodiment of the present invention, the photoinitiator includes at least one of benzophenone, 2,4-dihydroxybenzophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholin-1-propanone, isopropyl thioxanthone, and 2,4,6-trimethylbenzoyl diphenylphosphine oxide. Among them, the molar ratio of the photoinitiator to the carbon-carbon double bond in the modified phenolic resin with both photo-thermal curing properties can be (0.05-0.1):1.

[0088] In a specific embodiment of the present invention, the photoresist further includes a precursor for forming perovskite quantum dots. Among them, the composition of the precursor for forming perovskite quantum dots is adjusted and selected according to the type of perovskite required in actual situations.

[0089] In a specific embodiment of the present invention, the precursor for forming perovskite quantum dots includes an M source and a ligand. The M source includes a cesium source and / or a lead source; the ligand includes a first ligand methylammonium bromide (MABr) and / or a second ligand octylammonium bromide (OABr). Further, the molar ratio of the M source, the first ligand, and the second ligand is 1:(1.5-2.5):(0-0.4).

[0090] In a specific embodiment of the present invention, the molar ratio of the M source to the carbon-carbon double bond in the modified phenolic resin with both photo-thermal curing properties is (0.1-0.2):1.

[0091] The preparation method of the photoresist of the present invention includes: mixing and dissolving the above-mentioned components in proportion.

[0092] On the other hand, the present invention provides a method for patterning perovskite quantum dots, including the following steps: disposing any one of the above-mentioned photoresists on a substrate, performing ultraviolet light exposure treatment under the coverage of a mask plate to in-situ generate perovskite quantum dots, and developing with a developer; then performing heat treatment at 80-120 °C for 0.5-2 h.

[0093] The photo-reaction between the double bond in the modified phenolic resin with both photo-thermal curing properties of the present invention and the multi-mercapto compound realizes the photolithographic patterning of the phenolic resin. After the development process is completed, through a certain post-baking heat treatment, the epoxy functional group of the modified phenolic resin with both photo-thermal curing properties reacts with the polyamine compound to realize thermal curing crosslinking. Through photo-thermal double crosslinking curing, the in-situ generated perovskite quantum dots and their ligands are more effectively fixed in the crosslinked network system, thereby improving problems such as easy aggregation of quantum dots and easy detachment of ligands, and improving the stability of perovskite quantum dots and the devices prepared therefrom.

[0094] The photoresist obtained by the present invention using a modified phenolic resin with both photo-thermal curing properties has liquid fluidity and a certain viscosity, has good adhesion to the substrate, and has advantages such as in-situ generation of perovskite quantum dots, high-resolution lithographic patterning, and high-intensity light stability. The method of the present invention can meet the requirements of high stability, high precision, and large-area patterning, and has low cost and simple lithography process. The perovskite quantum dot pattern obtained by lithography has a power density of 150 mW / cm 2 After 24 hours of strong blue light testing, the PCE value does not decrease and remains at 105% - 116% of the initial value.

[0095] In different embodiments, during heat treatment, the temperature can be 80°C, 90°C, 100°C, 110°C, 120°C, or a range composed of any two of them; the heat treatment time can be 0.5 h, 0.8 h, 1 h, 1.5 h, 2 h, or a range composed of any two of them.

[0096] In a specific embodiment of the present invention, the developer includes acetone and / or chloroform.

[0097] In a specific embodiment of the present invention, the wavelength of the ultraviolet light is 350 - 380 nm, the exposure time of the ultraviolet light ≥ 5 s, and the exposure intensity of the ultraviolet light is 100 - 200 mJ / cm 2 。

[0098] In different embodiments, the wavelength of the ultraviolet light can be 350 nm, 360 nm, 370 nm, 380 nm, or a range composed of any two of them; the exposure time of the ultraviolet light can be 5 s, 10 s, 15 s, 20 s, or a range composed of any two of them; the exposure intensity of the ultraviolet light can be 100 mJ / cm 2 、120 mJ / cm 2 、150 mJ / cm 2 、180 mJ / cm 2 、200 mJ / cm 2 or a range composed of any two of them.

[0099] In actual operation, the substrate used for patterning is adjusted according to actual needs, and can be made of materials such as glass, PET, etc.

[0100] The present invention also provides a patterned perovskite quantum dot, which is prepared by using any one of the above perovskite quantum dot patterning methods.

[0101] Examples 1 - 2

[0102] This example provides a modified phenolic resin with both photo-thermal curing properties and a preparation method. The synthetic route is as follows:

[0103]

[0104] Among them, the synthesis route for the preparation of resin A is as follows:

[0105]

[0106] The specific preparation method includes: Preparation of allyl phenolic resin FR: Add 0.5 mol of o-allylphenol, 15.0150 g of paraformaldehyde (0.5 mol in terms of structural unit), 200 mL of deionized water, and 10 mL of concentrated hydrochloric acid (mass fraction of 36%) into a 500 mL round-bottom flask, and stir and react at 75 °C for 48 h. After the reaction is completed, extract with dichloromethane and water, collect the organic phase and dry it with anhydrous MgSO4. After evaporating the organic solvent to dryness by rotary evaporation, dry it at 50 °C to constant weight, and the yield is 92.3%.

[0107] Preparation of resin A: Add 29.4394 g of FR (about 0.20 mol of phenolic hydroxyl groups) and 0.06 mol of imidazole into a 500 mL round-bottom flask, and dissolve with 100 mL of anhydrous dichloromethane to form a homogeneous and transparent solution. Then, remove oxygen through three cycles of evacuation-inflation, and dropwise add 0.04 mol of dimethyldichlorosilane at 0 °C, and restore to room temperature for reaction for 12 h to obtain a stock solution containing resin A.

[0108] Preparation of modified phenolic resin with photo-thermal dual-curing performance: Add 0.02 - 0.04 mol of epichlorohydrin and 0.03 - 0.06 mol of imidazole into the above stock solution of resin A, and react at 70 °C for 6 h. After the reaction is completed, wash three times with dichloromethane and water, collect the organic phase and dry it with anhydrous MgSO4, filter with a vacuum pump to obtain the organic phase containing the product, evaporate the organic phase to dryness by rotary evaporation, and dry it in a vacuum drying oven at 50 °C to constant weight to obtain the preparation of modified phenolic resin with photo-thermal dual-curing performance, and the yield is 70% - 80%.

[0109] Among them, the main difference in the preparation of the modified phenolic resin with photo-thermal dual-curing performance corresponding to Examples 1 - 2 lies in the different dosages of epichlorohydrin and imidazole. The dosage of some materials and the product state corresponding to the preparation of the modified phenolic resin with photo-thermal dual-curing performance in each example are shown in Table 1.

[0110] Table 1 Preparation of different modified phenolic resins with photo-thermal dual-curing performance

[0111]

[0112] The 1H NMR and 13C NMR spectra of the resin A, FROS-EP-1, and FROS-EP-2 prepared in this example are respectively as Figure 1 and Figure 2As shown, it can be seen from the figure that epoxy functional groups are successfully grafted onto Resin A. FROS-EP-1 and FROS-EP-2 have different epoxy functional group contents. According to Figure 1 and Figure 2 characterization, the content of epoxy functional groups in FROS-EP-1 is lower than that in FROS-EP-2. The mass ratios of epoxy functional groups in FROS-EP-1 and FROS-EP-2 are approximately 1.75% and 3.5% respectively.

[0113] Example 3

[0114] This example provides a photoresist and its preparation method. The compositions of each photoresist are shown in Table 2.

[0115] The preparation of the photoresist includes: mixing each component, stirring and dissolving to form a clear and transparent solution.

[0116] Table 2 Compositions of Different Photoresists

[0117]

[0118] Example 4

[0119] This example provides a method for patterning perovskite quantum dots, which includes the following steps:

[0120] Spin-coat the prepared photoresist (2500 r / min, 30 s) on a clean glass slide, cover with a mask, and expose to 365 nm ultraviolet light for 10 s (152 mJ / cm 2 ), then develop with a developer to obtain the corresponding pattern; then place the photolithographed perovskite quantum dot film on a hot stage and heat-treat at 100 °C for 1 h.

[0121] Among them, in this example, the above patterning is respectively carried out using the 2 kinds of photoresists 3-1 and 3-2 in Example 3, and the pattern is obtained by developing in the developer acetone.

[0122] Comparative Example 1

[0123] Comparative Example 1 provides a photoresist and its preparation method. Referring to Example 3, the difference is that the composition of the photoresist is different.

[0124] The composition of the photoresist in Comparative Example 1 is shown in Table 3.

[0125] Table 3 Composition of the Photoresist in Comparative Example 1

[0126]

[0127] Comparative Example 1 provides a method for patterning perovskite quantum dots, which includes the following steps:

[0128] Spin coat the above-prepared photoresist (2500 r / min, 30 s) on a clean glass slide, cover it with a mask, and expose it to 365 nm ultraviolet light for 10 s (152 mJ / cm 2 ), then develop it with acetone to obtain the corresponding pattern.

[0129] Experimental Example

[0130] Spin coat the photoresist of Example 3 and the photoresist of Comparative Example 1 evenly (2500 r / min, 30 s) on a clean glass slide, and then expose it to 365 nm ultraviolet light for 10 s (152 mJ / cm 2 ), perform single photocuring to obtain the corresponding thin films respectively. Then place the obtained thin films under a blue light source with a brightness of about 3000 nit to test the blue light conversion. The test results are as Figure 3 shown. It can be seen from the figure that after single photocuring, there is no obvious difference in the blue light conversion of the photoresist of Example 3 and the photoresist of Comparative Example 1, PCE > 45%, CIEy > 0.72, indicating that the epoxy functional groups and polyamine substances introduced in the present invention do not affect photocuring.

[0131] Spin coat the photoresist of Example 3 and the photoresist of Comparative Example 1 evenly (2500 r / min, 30 s) on a clean glass slide, and then expose it to 365 nm ultraviolet light for 10 s (152 mJ / cm 2 ), then place the photolithographed perovskite quantum dot thin film on a hot stage and heat-treat it at 100 °C for 1 h to obtain the corresponding thin films respectively. Then place the obtained thin films under a blue light source with a brightness of about 3000 nit to test the blue light conversion. The test results are as Figure 4 shown. It can be seen from the figure that heat treatment causes the ripening and degradation of quantum dots, and there is no obvious difference in the blue light conversion of the photoresist of Example 3 and the photoresist of Comparative Example 1, PCE > 36%, CIEy > 0.74.

[0132] Further, place the above-mentioned films that have completed photo-thermal dual curing under a strong blue light of 150 mW / cm 2 for aging test, and at the same time test the sample of the photoresist of Comparative Example 1 that has undergone single photocuring as a control. After different strong blue light aging times, place it under a blue light source with a brightness of about 3000 nit to test the PCE and CIEy values, and the PVE and CIEy change conditions within 48 h are as Figure 5 and Figure 6As shown. It can be seen from the figure that for the sample of the photoresist in Comparative Example 1 that only undergoes single photocuring, the PCE drops to 53% of the initial value after 24 hours of strong blue light irradiation. For the sample of the photoresist in Comparative Example 1 that undergoes photo-thermal dual curing, the PCE remains at 94.7% of the initial value after 24 hours of strong blue light irradiation. For the two photoresists in Example 3 after photo-thermal dual curing, the PCEs remain at 105% and 116% of the initial value respectively after 24 hours of strong blue light irradiation, and the CIEy values show the same trend of change. From the perspective of 48-hour stability, the sample of the photoresist numbered 3-1 in Example 3 has the highest stability after photo-thermal dual curing, and the corresponding PCE value and CIEy value are also the highest. Thus, it can be seen that by introducing an appropriate content of epoxy functional groups onto Resin A and cooperating with polyamine compounds, a photoresist with specific photo-thermal dual curing can be prepared, which can be used to improve the stability of perovskite quantum dots. The more the content of epoxy groups, the more crosslinking points there are, and a dense crosslinking network is formed during the thermal curing process. An appropriate dense crosslinking network is beneficial to preventing quantum dot aggregation, but an overly dense network space may limit the growth of quantum dots, resulting in more defects in quantum dots and poorer stability.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A photoresist, characterized in that: The invention comprises a modified phenolic resin having light-heat dual curing performance, a polythiol compound, a polyamine substance, a photoinitiator and a solvent; the photoresist also comprises a precursor for forming perovskite quantum dots; The modified phenolic resin with light-heat dual curing properties and the polyamine substance are calculated based on epoxy group and amine group respectively, and the molar ratio is 1: (0.8-1.2); The modified phenolic resin having light-heat dual curing properties has at least one of the structures represented by the following general formula I or II: ； ； wherein a, b, c and d are each independently selected from integers between 0 and 10, y is selected from integers between 1 and 5, and x satisfies: 0<x / (x+a+b+c+d)≤0.2; R is selected from H and At least one of, e is selected from an integer between 0 and 6; The polyamine substances include at least one of 1,3-diaminopropane, N-aminoethylpiperazine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, branched polyethyleneimine, 1,4-diaminobutane, 1,5-diaminopentane, N,N',N''-trimethyldiethylenetriamine, 4-chloro-o-phenylenediamine, p-aminophenylethylamine, N-ethylpentylamine, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and 1,3-bis[3-[bis[3-[3-[3-(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane]propyl]amino-3-oxypropyl]amino]propyl]-1,1,3,3-tetramethyldisiloxane; The polythiol compound includes at least one of 1,2-ethanedithiol, 2,3-butanedithiol, 1,3-propanedithiol, 1,4-butanediol di(3-mercaptopropionate), 1,9-nonanedithiol, 3,6-dioxa-1,8-octanedithiol, 1,4-butanediol bis(thioglycolate), pentaerythritol tetrakis-3-mercaptopropionate and trimethylolpropane tris(3-mercaptopropionate); The precursor for forming perovskite quantum dots includes an M source and a ligand, wherein the M source includes a cesium source and / or a lead source; the ligand includes a first ligand methylammonium bromide and / or a second ligand octylammonium bromide; The method for patterning perovskite quantum dots comprises the following steps: placing the photoresist on a substrate, performing ultraviolet light exposure treatment under the cover of a mask plate, generating perovskite quantum dots in situ, developing with a developer; and then heat treating at 80 to 120° C. for 0.5 to 2 hours.

2. The photoresist according to claim 1, characterized in that x / (x+a+b+c+d) is 0.01~0.

1.

3. The photoresist according to claim 1, characterized in that a, b, c and d are each independently selected from integers between 0 and 6; e is selected from integers between 0 and 4.

4. The photoresist according to claim 1, characterized in that The method for preparing the modified phenolic resin having light-heat dual curing properties comprises the following steps: Resin A reacts with epichlorohydrin in a solvent under the action of an organic base; Wherein, the resin A has at least one structure represented by the following general formula III or IV: ； 。 5. The photoresist according to claim 4, characterized in that The molar ratio of the resin A, calculated based on the phenolic hydroxyl groups therein, to the epichlorohydrin is 1: (0.1-0.2); And / or, the organic base comprises imidazole.

6. The photoresist according to claim 5, characterized in that The molar ratio of the organic base to the epichlorohydrin is (1-2):

1.

7. The photoresist according to claim 4, characterized in that The reaction temperature is 60-80° C., and the reaction time is 4-8 hours.

8. The photoresist according to claim 1, characterized in that The molar ratio of the modified phenolic resin with light-heat dual curing properties to the mercapto groups in the polythiol compound is 1:(0.5-2), based on the carbon-carbon double bonds therein.

9. The photoresist according to claim 1, characterized in that The solvent includes at least one of N-methylpyrrolidone, N,N-dimethylformamide, dimethyl sulfoxide and acetonitrile.

10. A method for patterning perovskite quantum dots, characterized in that: The method comprises the following steps: placing the photoresist described in any one of claims 1 to 9 on a substrate, performing ultraviolet light exposure treatment under the cover of a mask plate, generating perovskite quantum dots in situ, and developing the perovskite quantum dots with a developer; and then performing a heat treatment at 80 to 120° C. for 0.5 to 2 hours.

11. Patterned perovskite quantum dots, characterized in that The perovskite quantum dot patterning method according to claim 10 is used to prepare the material.

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