Siloxime ester photoinitiators, their preparation methods and applications

Abstract

This invention provides a siloxime ester-containing photoinitiator. The siloxime ester-containing photoinitiator has the chemical structure shown in formula (I), wherein R1 is selected from C1-C8 alkylene groups; A, B, and C are each independently selected from C1-C8 alkyl groups or C6-C6 alkylene groups. 10 Aryl; R2 is selected from hydrogen or C1-C8 alkyl; R3 is selected from C1-C8 alkyl and cleaved by 1-3 oxygen atoms; R4 is selected from C1-C8 alkyl or C6-C6 alkyl. 10 Aryl group. Siloxime ester initiators with the above structure exhibit high sensitivity, and the introduction of the R3 group can significantly improve the solubility of siloxime ester initiators during application, thereby enhancing their resistance during application.

Description

Technical Field

[0001] This invention relates to the field of photocuring, and more specifically, to a siloxime ester-containing photoinitiator, its preparation method, and its application. Background Technology

[0002] Oxime esters, as effective type I photoinitiators, have long been used in free radical photopolymerization due to their superior photoreactivity. After the N and O bonds of oxime esters break, the acyloxy group undergoes a decarboxylation reaction to produce carbon dioxide. This solves the polymerization inhibition problem caused by oxygen in the air, making them widely used photoinitiators.

[0003] Oxime ester photoinitiators are widely used in the production of various photoresists due to their relatively superior performance. In the color filters of traditional LCD panels, oxime ester initiators can be used in BM photoresists (Black Matrix). However, the next generation of displays has put forward higher requirements for the resolution, optical density, and surface impedance of BM photoresists, which also puts forward higher requirements for initiators. Summary of the Invention

[0004] The main objective of this invention is to provide a siloxime ester-containing photoinitiator, its preparation method, and its application, so as to further improve the resolution, optical density, and surface impedance of oxime ester-based photoinitiators in application.

[0005] To achieve the above objectives, the present invention provides a siloxime ester-containing photoinitiator having the chemical structure shown in formula (I):

[0006]

[0007] Wherein, R1 is selected from C1 to C8 alkylene groups; A, B, and C are each independently selected from C1 to C8 alkyl groups or C6 to C8 alkyl groups. 10 Aryl; R2 is selected from hydrogen or C1-C8 alkyl; R3 is selected from C1-C8 alkyl and cleaved by 1-3 oxygen atoms; R4 is selected from C1-C8 alkyl or C6-C6 alkyl. 10 Aryl.

[0008] To achieve the above objectives, another aspect of the present invention provides a method for reacting the fourth intermediate with an acylating agent in the presence of a third type of base and a fourth solvent to obtain the siloxime ester-containing photoinitiator, wherein the first intermediate, second intermediate, third intermediate, and fourth intermediate have the following structures:

[0009]

[0010] Where X is a halogen, and R1, A, B, C, R2, R3, and R4 have the same definitions as above.

[0011] Another aspect of the present invention provides the application of the above-mentioned siloxime ester-containing photoinitiator in photoresists, paints, coatings, inks or molding materials.

[0012] By applying the technical solution of the present invention, the siloxime ester initiator having the above-mentioned structure has the characteristic of high sensitivity, and the introduction of the R3 group can significantly improve the solubility of the siloxime ester initiator during application, thereby improving its resistance during application. Detailed Implementation

[0013] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the embodiments.

[0014] As described in the background section, oxime ester initiators can be applied to BM photoresists. Next-generation displays place higher demands on the resolution, optical density, and surface impedance of BM photoresists. To address these technical problems, this application provides a siloxime ester-containing photoinitiator, characterized in that the siloxime ester-containing photoinitiator has the chemical structure shown in formula (I):

[0015]

[0016] Wherein, R1 is selected from C1 to C8 alkylene groups; A, B, and C are each independently selected from C1 to C8 alkyl groups or C6 to C8 alkyl groups. 10 Aryl; R2 is selected from hydrogen or C1-C8 alkyl; R3 is selected from C1-C8 alkyl and cleaved by 1-3 oxygen atoms; R4 is selected from C1-C8 alkyl or C6-C6 alkyl. 10 Aryl.

[0017] The siloxime ester initiator with the above structure has the characteristics of high sensitivity, and the introduction of the R3 group can significantly improve the solubility of the siloxime ester initiator during application, thereby improving its resistance during application.

[0018] To reduce the difficulty of its synthesis and improve its yield, photosensitivity and resistance, preferably, R1 includes, but is not limited to, C1-C4 alkylene groups; R2 includes, but is not limited to, methyl, ethyl or propyl; A, B, and C are independently including, but not limited to, methyl, ethyl, propyl or phenyl; R3 includes, but is not limited to, C4-C6 alkyl groups and is cleaved by 2 or 3 oxygen atoms; R4 includes, but is not limited to, methyl, ethyl, propyl, phenyl, methylphenyl, ethylphenyl or naphthyl.

[0019] To further improve the resistance of its application process, R3 is preferably including but not limited to -O-(CH2)2-O-CH2-CH3, -O-(CH2)2-O-(CH2)2-O-CH2-CH3 or -O-CH(CH3)-CH2-O-CH3.

[0020] To further improve the overall performance of siloxime ester-containing initiators, the structure of each substituent group can be optimized. Preferably, siloxime ester-containing photoinitiators include, but are not limited to, one or more of the following compounds:

[0021]

[0022]

[0023] A second aspect of this application also provides a method for preparing the above-mentioned siloxime ester-containing photoinitiator, comprising: alkylating carbazole and a halosilane in the presence of a first base and a first solvent to obtain a first intermediate; reacting the first intermediate with an acyl chloride in the presence of a catalyst to obtain a second intermediate; reacting the second intermediate with a nitro reagent in the presence of a second solvent to obtain a third intermediate; reacting the third intermediate with hydroxylamine hydrochloride in the presence of a second base and a third solvent to obtain a fourth intermediate; and reacting the fourth intermediate with an acylating reagent in the presence of a third base and a fourth solvent to obtain a siloxime ester-containing photoinitiator, wherein the first, second, third, and fourth intermediates have the following structures:

[0024]

[0025] Where X is a halogen, and R1, A, B, C, R2, R3, and R4 have the same definitions as those mentioned above.

[0026] A preferred synthetic route is as follows:

[0027]

[0028] Preferably, in the alkylation reaction, the first type of base includes, but is not limited to, one or more of potassium hydroxide, sodium hydroxide and sodium hydride, the first solvent includes, but is not limited to, one or more of tetrahydrofuran, dimethylformamide or toluene, and the reaction temperature is 0 to 100°C.

[0029] Preferably, in the Friedel-Crafts reaction, the catalyst includes, but is not limited to, Lewis acids and / or protic acids. Preferably, the Lewis acids include, but are not limited to, one or more of aluminum trichloride, tin chloride, zinc chloride, and ferric chloride, and the protic acids include, but are not limited to, one or more of hydrogen fluoride, sulfuric acid, and phosphoric acid. The reaction temperature is -10 to 30°C.

[0030] Preferably, in the nitration reaction, the nitrating agent includes, but is not limited to, one or more of concentrated nitric acid, fuming nitric acid, sodium nitrate and nitrate ester, and the reaction temperature is -10 to 30°C.

[0031] Preferably, in the oxime reaction, the second type of base includes, but is not limited to, one or more of ammonium acetate, sodium acetate, potassium acetate, triethylamine, sodium hydroxide, and potassium hydroxide, and the second solvent includes, but is not limited to, one or more of methanol, ethanol, and N,N-dimethylformamide, and the reaction temperature is 50–100°C.

[0032] Preferably, in the esterification reaction, the acylation reagent is an acyl halide and / or an anhydride, the third type of base includes, but is not limited to, one or more of triethylamine, pyridine, diisopropylethylamine, potassium hydroxide, sodium hydroxide and sodium hydride, and the fourth solvent includes, but is not limited to, one or more of diethyl ether, acetonitrile, tert-butyl methyl ether, tetrahydrofuran, vinyl acetate, toluene, xylene, acetone, methyl ethyl ketone, dichloromethane (DCM), chloroform, chlorobenzene, dimethylacetamide and dimethylformamide, and the reaction temperature is -10 to 60°C.

[0033] Preferably, the acyl halide is selected from cyclohexanoyl chloride, 2-propylpentanoyl chloride, 3,5,5-trimethylhexanoyl chloride, 3-chloropropionyl chloride, 5-chloropentanoyl chloride, 3-chloropentanoyl chloride, 6-bromohexanoyl chloride, methoxyacetyl chloride, ethoxyacetyl chloride, butoxyacetyl chloride, 3-(methylthio)propionyl chloride, (2-butoxyethoxy)acetyl chloride, benzoyl chloride, tolueneyl chloride, 3,5-dimethylbenzoyl chloride, 4-methoxybenzoyl chloride, 4-cyanobenzoyl chloride, 4-nitrobenzoyl chloride, 4-phenylbenzoyl chloride, chlorobenzoyl chloride, phenylacetyl chloride, benzene One or more of the following: propionyl chloride, chlorophenylacetyl chloride, 4-phenylbutyryl chloride, 6-phenylhexanoyl chloride, nitrophenylacetyl chloride, phenoxyacetyl chloride, phenoxypropionyl chloride, chlorophenoxyacetyl chloride, nitrophenoxyacetyl chloride, 2-thiophenecarboxyl chloride, thiophene-2-acetyl chloride, chloronicotinyl chloride, 2-furanoyl chloride, quinolinecarboxyl chloride, naphthyl chloride, 2-ethoxy-1-naphthoyl chloride, and anthracenecarboxyl chloride; and one or more of the following: acetic anhydride, propionic anhydride, decanoic anhydride, stearic anhydride, isobutyric anhydride, tert-valerate anhydride, and 4-methoxyphenylacetic anhydride.

[0034] In the preparation of the above-mentioned siloxime ester photoinitiator, the reaction reagents used are all known compounds in the prior art, which can be obtained commercially or conveniently prepared by existing synthetic methods.

[0035] The initiator shown in formula (I) of this invention can be used in UV-LED curing systems, and is particularly suitable for initiation under a 365nm light source. It has excellent sensitivity and exhibits resistance after application.

[0036] A third aspect of this application also provides the application of the above-mentioned siloxime ester-containing photoinitiator in photoresists, paints, coatings, inks, or molding materials.

[0037] The aforementioned siloxime ester-containing photoinitiators can be used in photoresist products. Meanwhile, the aforementioned siloxime ester-containing photoinitiators can also be used in paints, coatings, inks, and molding materials. Specifically, they can be used to manufacture: coatings applied to substrates such as plastics, metals, glass, ceramics, wood, and walls; protective film materials such as hard coating agents, antifouling films, antireflective films, and impact-absorbing films; photocurable adhesives, photodegradable coatings, films, and molded products; optical recording media such as holographic imaging materials; optical molding resins, such as inks (resins) for 3D printing, photoresists for electronic circuits and semiconductor manufacturing, and photoresists for electronic materials such as color filters, black matrices, and dry films in displays; interlayer insulating films, light extraction films, brightness enhancement films, and sealing materials; printing inks for screen printing, offset printing, and gravure printing, and photocurable inks for inkjet printing; optical components such as lenses, lens arrays, waveguides, light guide plates, light diffusers, and diffraction elements; optical spacers, ribs, nanoimprinting materials, quantum dots, OLEDs, etc.

[0038] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.

[0039] Preparation Examples

[0040] Example 1

[0041]

[0042] (1) Preparation of intermediate 1b

[0043]

[0044] 100 g of carbazole was added to a 1000 mL three-necked flask and dissolved in 400 g of DMF. Then, 100 g of (3-chloropropyl)trimethylsilane was added, and 36 g of sodium hydride was added in batches over an ice-water bath. After the addition was complete, the temperature was raised to 80 °C and the reaction was allowed to proceed for 2 hours. The reaction solution was then slowly poured into ice water to quench the reaction, and 400 mL of dichloromethane (DCM) was added for extraction. After standing and separating the aqueous layer, the organic phase was washed five times with water, dried over anhydrous sodium sulfate, and the solvent was removed by vacuum evaporation to obtain a brown oily substance. 400 g of methanol was added to crystallize the substance in an ice-water bath, and the crystals were filtered, dried, and 153 g of grayish-white powder was obtained. The HPLC purity was 98.71%, and the yield was 91.07 wt%.

[0045] (2) Preparation of intermediate 1c

[0046]

[0047] 140 g of intermediate 1b and 700 mL of dichloromethane were added to a 2000 mL three-necked flask and stirred to dissolve. Then 73 g of aluminum trichloride was added, and the mixture was cooled to 0 °C with ice water. 127 g of acyl chloride was added dropwise, and the temperature was controlled within 0–5 °C. The addition was completed in 2 h, and the reaction continued for another h. After the reaction was completed under HPLC monitoring, the reaction solution was slowly poured into 700 g of ice water for hydrolysis. After stirring for 1 h, the aqueous layer was separated, and the organic phase was washed with water (300 g × 3 times). The solution was dried over anhydrous sodium sulfate, concentrated, and 500 g of methanol was added to obtain 207 g of off-white solid intermediate 1c, with a yield of 85.12% and an HPLC purity of 98.02 wt%.

[0048] (3) Preparation of compound 1d

[0049]

[0050] In a 500 mL three-necked flask, 48.8 g of intermediate 1c and 300 g of dichloromethane were added and stirred until dissolved. The mixture was cooled to 0 °C, and a mixture of 8.3 g of fuming nitric acid and 40 g of dichloromethane was added dropwise over 2 hours. The reaction was maintained at this temperature for 2 hours, and the reaction was stopped under HPLC control. The reaction solution was slowly poured into 300 g of ice water to quench the reaction, stirred for 1 hour, and then allowed to stand to separate the aqueous layer. The organic layer was washed with water (200 g × 3 times), dried over anhydrous sodium sulfate, and concentrated until no liquid was produced. The residue was dissolved in 200 g of ethyl acetate, cooled to 0-5 °C, and stirred to crystallize for 2 hours. The solution was filtered to obtain 43.3 g of a yellow solid, with a yield of 81.27 wt% and a purity of 98.14%.

[0051] (4) Preparation of compound 1e

[0052]

[0053] In a 1000 mL three-necked flask, 53.3 g of intermediate 1d, 400 g of ethanol, 34.8 g of hydroxylamine hydrochloride, and 49.2 g of sodium acetate were added. The mixture was heated and refluxed for 240 h, with the reaction controlled by HPLC. The mixture was then cooled to 5-10 °C, filtered, washed with methanol, and dried to obtain 47.2 g of a yellow solid, with a yield of 86.20 wt% and a purity of 97.43%.

[0054] (5) Preparation of compound 1

[0055]

[0056] 27.4 g of intermediate 1e, 150 g of dichloromethane, and 0.3 g of dimethylaminopyridine were added to a 250 mL three-necked flask. 7.6 g of acetic anhydride was added dropwise at 20-25 °C over 0.5 h. The reaction mixture was kept at this temperature for 2 h, and the reaction was stopped under HPLC control. The reaction solution was slowly poured into 200 g of ice water to quench the reaction. After stirring for 1 h, the aqueous layer was separated, and the organic layer was washed with water (100 g × 3 times). After drying with anhydrous sodium sulfate, the solution was concentrated until no liquid was produced. 150 g of acetone was added to induce crystallization at 0-5 °C for 2 h. The crystals were filtered and dried to obtain 25.7 g of a pale yellow solid, with a yield of 87.31 wt% and a purity of 99.23%. The 1H NMR spectrum is as follows:

[0057] 1H NMR(500MHz,Chloroform-d)δ9.18(d,J=1.6Hz,1H),8.18(d,J=1.4Hz,1H),8.10(dd,J=7.4,1.4Hz,1H),7.78(d,J=7 .5Hz,1H),7.58(d,J=7.4Hz,1H),7.50(dd,J=7.5,1.5Hz,1H),7.27(dq,J=7.4,1.0Hz,1H),7.06(dd,J=7.6,1.5Hz,1H ),6.76(d,J=1.5Hz,1H),4.12(t,J=7.1Hz,2H),4.01(t,J=7.1Hz,2H),3.76(t,J=7.0Hz,2H),3.55(q,J=8.0Hz,2H),2 .47(d,J=1.1Hz,3H),2.15(s,3H),1.61(p,J=7.1Hz,2H),1.17(t,J=8.0Hz,3H),0.68(t,J=7.1Hz,2H),-0.14(s,9H).

[0058] Example 2

[0059]

[0060] (1) Preparation of intermediate 2b (same as in Example 1)

[0061]

[0062] 100 g of carbazole was added to a 1000 mL three-necked flask and dissolved in 400 g of DMF. Then, 100 g of (3-chloropropyl)trimethylsilane was added, and 36 g of sodium hydride was added in batches over an ice-water bath. After the addition was complete, the temperature was raised to 80 °C and the reaction was allowed to proceed for 2 hours. The reaction solution was then slowly poured into ice water to quench the reaction, and 400 mL of dichloromethane was added for extraction. After standing and separating the aqueous layer, the organic phase was washed five times with water, dried over anhydrous sodium sulfate, and the solvent was removed by vacuum evaporation to obtain a brown oily substance. 400 g of methanol was added to crystallize the substance in an ice-water bath, and the crystals were filtered, dried, and 153 g of grayish-white powder was obtained. The HPLC purity was 98.71%, and the yield was 91.07 wt%.

[0063] (2) Preparation of intermediate 2c

[0064]

[0065] Add 56.2 g of intermediate 2b and 250 mL of dichloromethane to a 500 mL three-necked flask, stir to dissolve, then add 29.3 g of aluminum trichloride, cool to 0 °C with ice water, and add 63.1 g of acyl chloride dropwise, controlling the temperature between 0 and 5 °C. After the addition is completed in 2 hours, continue the reaction for another hour. Once the reaction is complete under HPLC monitoring, slowly pour the reaction solution into 300 g of ice water for hydrolysis, stir for 1 hour, and allow it to stand to separate the aqueous layer. Wash the organic phase with water (200 g × 3 times), dry with anhydrous sodium sulfate, and concentrate to obtain a brown oily intermediate 1c with an HPLC purity of 97.54%. No crystallization purification is required; proceed directly to the next step.

[0066] (3) Preparation of compound 2d

[0067]

[0068] Add the oily intermediate 2c from the previous step and 250g of dichloromethane to a 500mL three-necked flask, stir until dissolved, cool to 0℃, and add dropwise a mixture of 15.1g of fuming nitric acid and 60g of dichloromethane over 2 hours. Maintain the reaction temperature for 2 hours, and then allow the reaction to stop under HPLC control. Slowly quench the reaction mixture in 300g of ice water, stir for 1 hour, and allow it to stand to separate the aqueous layer. Wash the organic layer with water (200g × 3 times), dry with anhydrous sodium sulfate, and concentrate until no liquid is dispensed. Dissolve the residue in 200g of ethyl acetate, cool to 0-5℃, and stir to crystallize for 2 hours. Filter to obtain 83.7g of yellow solid, with a two-step yield of 72.58wt% and a purity of 98.03%.

[0069] (4) Preparation of compound 2e

[0070]

[0071] In a 1000 mL three-necked flask, 57.7 g of intermediate 1d, 400 g of ethanol, 34.8 g of hydroxylamine hydrochloride, and 49.2 g of sodium acetate were added. The mixture was heated and refluxed for 300 h, with the reaction proceeding under HPLC monitoring. The mixture was then cooled to 5-10 °C, filtered, washed with methanol, and dried to obtain 49.4 g of a yellow solid, with a yield of 83.45 wt% and a purity of 97.28%.

[0072] (5) Preparation of compound 2

[0073]

[0074] Add 29.6 g of intermediate 2e, 150 g of dichloromethane, and 0.3 g of dimethylaminopyridine to a 250 mL three-necked flask. Add 7.6 g of acetic anhydride dropwise over 0.5 h until the addition is complete, and maintain the temperature.

[0075] The reaction was completed under HPLC control after 2 hours. The reaction solution was slowly poured into 200g of ice water to quench the reaction, stirred for 1 hour, and then allowed to stand to separate the aqueous layer. The organic layer was washed with water (100g × 3 times), dried over anhydrous sodium sulfate, and concentrated until no liquid was produced. 150g of acetone was added to induce crystallization at 0-5℃ for 2 hours. The crystals were filtered and dried to obtain 26.9g of a pale yellow solid, with a yield of 85.03wt% and a purity of 99.07%. The 1H NMR spectrum is as follows:

[0076] 1 H NMR(500MHz,Chloroform-d)δ9.18(d,J=1.6Hz,1H),8.17(d,J=1.4Hz,1H),8.10(dd,J=7.4,1.4Hz,1H),7.78(d,J=7.5Hz,1H) ,7.61(d,J=7.4Hz,1H),7.46(dd,J=7.4,1.4Hz,1H),7.27(dq,J=7.7,1.1Hz,1H),7.06(dd,J=7.6,1.5Hz,1H),6.77(d,J=1.5Hz ,1H),4.13(t,J=7.1Hz,2H),4.01(t,J=7.1Hz,2H),3.77(t,J=7.0Hz,2H),3.69–3.63(m,2H),3.63–3.56(m,2H),3.54(q,J=8.0 Hz, 2H), 2.47 (d, J = 1.1Hz, 3H), 2.15 (s, 3H), 1.61 (p, J = 7.1Hz, 2H), 1.15 (t, J = 8.1Hz, 3H), 0.68 (t, J = 7.1Hz, 2H), -0.14 (s, 9H).

[0077] Example 3-12

[0078] Following the method of Example 1 or 2, by changing the corresponding raw materials, the following compounds 3-12 were prepared, and their structures and corresponding NMR characterization data are listed in Table 1 below.

[0079] Table 1

[0080]

[0081]

[0082]

[0083] Performance Evaluation 1. Photosensitive Performance Test

[0084] It should be noted that the photocurable compositions used in all embodiments and comparative examples of this application for photosensitive testing were prepared according to the following proportions. Specifically, by weight, the photocurable composition comprises: 200 parts of acrylate copolymer, 100 parts of dipentaerythritol hexaacrylate, 5 parts of photoinitiator, 900 parts of butanone (solvent), and 5 parts of carbon black. The aforementioned acrylate copolymer (manufacturer: Changzhou Qiangli Electronic New Materials Co., Ltd.) is a copolymer of benzyl methacrylate / methacrylic acid / hydroxyethyl methacrylate (molar ratio 70:10:20), Mw = 10000.

[0085] In the above-described photocurable compositions, the photoinitiator is an oxime ester compound represented by general formula (I) in the foregoing description of this application or a similar photoinitiator known in the prior art for comparison. Specific formulations for all embodiments and comparative examples of this application are shown in Table 2.

[0086] Table 2

[0087]

[0088]

[0089]

[0090] (1) Photosensitive test

[0091] The above composition was stirred in the dark and then coated onto a 21-step gradient rod using a #6 wire rod to form a film with a thickness of approximately 15 μm. The coating was then exposed to an LED lamp (385 nm) at a flux of 191 mJ / cm². 2 The energy (100% light intensity, 8 m / min × 2 times) was used to develop the gradient scale after curing with 2% NaOH aqueous solution for 2 min, followed by rinsing with tap water for 1 min. The test results of the gradient scale were then observed.

[0092] Table 3

[0093]

[0094] (2) Resistance performance test of the formulation

[0095] Referring to the specific formula shown in Table 2, prepare the photocurable composition, place the coating in an oven at 230°C and bake for 150 minutes. After removing it, use a Hiresta-UXMCP-HT800 impedance meter to measure the surface impedance, test probe URS, and test voltage 10V.

[0096] Table 4

[0097]

[0098] In summary, the siloxime ester initiator of formula (I) disclosed in this invention has the characteristics of high sensitivity and excellent resistance performance after application.

[0099] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those described herein.

[0100] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A photoinitiator containing siloxime esters, characterized in that, The siloxime ester-containing photoinitiator has the chemical structure shown in formula (I): Equation (I) Wherein, R1 is selected from C1-C8 alkylene groups; A, B, and C are each independently selected from C1-C8 alkyl groups or C6-C6 alkylene groups. 10 aryl; R2 is selected from hydrogen or C1~C8 alkyl; R3 is selected from -O-(CH2)2-O-CH2-CH3, -O-(CH2)2-O-(CH2)2-O-CH2-CH3 or -O-CH(CH3)-CH2-O-CH3; R4 is selected from C1~C8 alkyl or C6~C 10 Aryl.

2. The siloxime-containing photoinitiator according to claim 1, characterized in that, R1 is selected from C1 to C4 alkylene groups; R2 is selected from methyl, ethyl, or propyl; A, B, and C are each independently selected from methyl, ethyl, propyl, or phenyl; and R4 is selected from methyl, ethyl, propyl, phenyl, or naphthyl.

3. A photoinitiator containing siloxime esters, characterized in that, The siloxime-containing photoinitiator is selected from one or more of the following compounds: Compound 1 Compound 2 Compound 3 Compound 4 Compound 5 Compound 6 Compound 7 Compound 8 Compound 9 Compound 10 Compound 11 Compound 12.

4. A method for preparing the siloxime ester-containing photoinitiator according to claim 1, characterized in that, The preparation method of the siloxime ester-containing photoinitiator includes: In the presence of a first type of base and a first solvent, carbazole and a halosilane undergo an alkylation reaction to obtain a first intermediate; In the presence of a catalyst, the first intermediate is reacted with an acyl chloride in a Friedel-Crafts reaction to obtain the second intermediate; In the presence of a second solvent, the second intermediate is subjected to a nitration reaction with a nitro reagent to obtain a third intermediate; In the presence of a second type of base and a third solvent, the third intermediate is subjected to an oxime reaction with hydroxylamine hydrochloride to obtain a fourth intermediate; In the presence of a third type of base and a fourth solvent, the fourth intermediate and the acylating agent are subjected to an esterification reaction to obtain the siloxime ester-containing photoinitiator. The first intermediate, the second intermediate, the third intermediate, and the fourth intermediate have the following structures: First intermediate Second intermediate, Third intermediate Fourth intermediate, R1, A, B, C, R2, and R3 have the same definitions as in claim 1.

5. The method for preparing the siloxime-containing photoinitiator according to claim 4, characterized in that, In the alkylation reaction, the first type of base is selected from one or more of potassium hydroxide, sodium hydroxide, and sodium hydride, the first solvent is selected from one or more of tetrahydrofuran, dimethylformamide, or toluene, and the reaction temperature is 0~100℃.

6. The method for preparing the siloxime-containing photoinitiator according to claim 4, characterized in that, In the Friedel-Crafts reaction, the catalyst is selected from Lewis acids and / or protic acids, wherein the Lewis acid is selected from one or more of aluminum trichloride, tin chloride, zinc chloride, and ferric chloride, and the protic acid is selected from one or more of hydrogen fluoride, sulfuric acid, and phosphoric acid, and the reaction temperature is -10 to 30°C.

7. The method for preparing the siloxime-containing photoinitiator according to claim 4, characterized in that, In the nitration reaction, the nitrating agent is selected from one or more of concentrated nitric acid, fuming nitric acid, sodium nitrate and nitrate ester, and the reaction temperature is -10~30℃.

8. The method for preparing the siloxime-containing photoinitiator according to claim 4, characterized in that, In the oxime reaction, the second type of base is selected from one or more of ammonium acetate, sodium acetate, potassium acetate, triethylamine, sodium hydroxide, and potassium hydroxide, the second solvent is selected from one or more of methanol, ethanol, and N,N-dimethylformamide, and the reaction temperature is 50~100℃.

9. The method for preparing the siloxime-containing photoinitiator according to claim 4, characterized in that, In the esterification reaction, the acylating agent is an acyl halide and / or an anhydride; the third type of base is selected from one or more of triethylamine, pyridine, diisopropylethylamine, potassium hydroxide, sodium hydroxide, and sodium hydride; the fourth solvent is selected from one or more of diethyl ether, acetonitrile, tert-butyl methyl ether, tetrahydrofuran, vinyl acetate, toluene, xylene, acetone, methyl ethyl ketone, dichloromethane, chloroform, chlorobenzene, dimethylacetamide, and dimethylformamide; and the reaction temperature is -10 to 60°C. The acyl halide is one or more of cyclohexanoyl chloride, 2-propylpentanoyl chloride, 3,5,5-trimethylhexanoyl chloride, benzoyl chloride, and naphthanoyl chloride, and the acid anhydride is selected from one or more of acetic anhydride, propionic anhydride, isobutyric anhydride, and tert-valerate anhydride.

10. The use of a siloxime ester-containing photoinitiator according to any one of claims 1 to 3 in photoresists, coatings, inks or molding materials.

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