Bis-carbazolyl sulfonium salt-containing compound as well as preparation method and application thereof
By designing biscarbazolium thioonium salt compounds, the problems of poor compatibility between existing photoinitiators and LED light sources and low photolysis efficiency have been solved, achieving high-efficiency photosensitivity and wide spectral response, making them suitable for photochemical applications in multiple scenarios.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHENGDU VITUOLI FLEXIBLE ELECTRONICS TECH CO LTD
- Filing Date
- 2026-03-03
- Publication Date
- 2026-05-26
AI Technical Summary
Existing photoinitiators are difficult to effectively match with LED light sources, have insufficient absorption wavelength, low photolysis efficiency, poor thermal stability, and their structural uniformity limits the redshift of absorption wavelength. Furthermore, the synthesis steps are complex and the product purity is low.
By introducing biscarbazole-thioonium salt compounds, the photosensitivity is enhanced by the synergistic effect of the biscarbazole skeleton and the thioonium salt group, the absorption wavelength covers the range of 365–420 nm, and the free radical generation rate and anti-oxidation ability are improved.
It achieves efficient matching with LED light sources, significantly improves photosensitivity, is suitable for photochemical processes in multiple scenarios, and meets the needs of high-precision patterning and high-value-added fields.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of photochemical technology, and particularly relates to a biscarbazolium thioonium salt compound, its preparation method, and its application. Background Technology
[0002] Photoinitiators are the core components of photocuring technology, and their performance directly affects the polymerization rate, material stability, and the mechanical properties of the final product. Traditional photoinitiators (such as oxime esters and thioonium salts) have the following limitations: poor absorption wavelength matching: the absorption peaks of most commercial photoinitiators (such as TPO and iodonium salts) are concentrated in the short-wave ultraviolet region (<300 nm), making it difficult to effectively match with LED light sources (365–405 nm), requiring multi-component systems or complex modifications, leading to increased application costs; insufficient photolysis efficiency: existing thioonium salt photoinitiators (such as diphenylthioonium salts) are easily affected by the cage effect during photolysis, resulting in low free radical yield and poor thermal stability; structural uniformity: traditional carbazole-based photoinitiators are mostly monosubstituted or simple conjugated structures with limited conjugated chain length, making it difficult to achieve an effective redshift of the absorption wavelength through intramolecular charge transfer (ICT).
[0003] In recent years, researchers have optimized photoinitiator performance by introducing conjugated groups (such as biphenyl and stilbene) or heterocyclic structures. For example, the carbazole skeleton, due to its rigid planar structure and strong electron delocalization, has been shown to significantly enhance photosensitivity. Furthermore, the ability of thioonium salt groups to generate free radicals through the photolysis of CS bonds makes them highly efficient photoinitiator candidates. However, current techniques for combining carbazole with thioonium salts still suffer from complex synthetic steps, low product purity, and a lack of systematic optimization for LED light sources. Summary of the Invention
[0004] In view of this, the purpose of this invention is to provide a biscarbazole-containing thioonium salt compound, its preparation method, and its applications. The compound provided by this invention significantly enhances photosensitivity through the synergistic effect of the biscarbazole skeleton and the thioonium salt group.
[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a compound containing a biscarbazolium thioonium salt, having the structure shown in formula (I): Formula (I); R1 is independently selected from H, alkyl groups with 1 to 50 carbon atoms (substituted or unsubstituted), cycloalkyl groups with 3 to 30 carbon atoms (substituted or unsubstituted), aryl groups with 6 to 50 carbon atoms (substituted or unsubstituted), and heteroaromatic groups with 5 to 60 carbon atoms (substituted or unsubstituted). R2 is independently selected from H, halogen atom, cyano, nitro, alkoxy, haloalkyl, acyl, acyloxy, sulfonyl, substituted or unsubstituted alkyl with 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 30 carbon atoms, substituted or unsubstituted cycloalkyl with 6 to 50 carbon atoms, and substituted or unsubstituted heteroaromatic group with 5 to 60 carbon atoms. R3 is independently selected from H, halogen atom, cyano, nitro, alkoxy, haloalkyl, acyl, acyloxy, sulfonyl, substituted or unsubstituted alkyl with 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 30 carbon atoms, substituted or unsubstituted cycloalkyl with 6 to 50 carbon atoms, and substituted or unsubstituted heteroaromatic group with 5 to 60 carbon atoms. M - X represents - ClO4 - CN - HSO4 - NO3 - CF3COO - (BX4) - (SbX6) - (AsX6) - (PX6) - Al[OC(CF3)3]4 - R4SO3 - (R4SO2)3C - (R4SO2)2N - B(C6X5)4 - Ga(C6X5)4 - In this formula, X represents a halogen, and R4 represents an alkyl group with 1 to 50 carbon atoms, a perfluoroalkyl group with 1 to 50 carbon atoms, an aryl group with 6 to 50 cyclic carbon atoms, or a substituted aryl group.
[0006] Preferably, the biscarbazolylthioonium salt compound is selected from any one of the compounds shown in the following structural formulas:
[0007]
[0008]
[0009]
[0010]
[0011]
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
[0018]
[0019]
[0020]
[0021] .
[0022] This invention also provides a method for preparing a compound containing a biscarbazolyl thioonium salt, wherein the preparation method is carried out according to the following synthetic route: .
[0023] The present invention also provides a UV-curable composition comprising the above-described biscarbazolium thioonium salt compound.
[0024] The present invention also provides a UV-curable composition comprising the above-described biscarbazolium thioonium salt compound.
[0025] This invention also provides the application of the above-described biscarbazolium thioonium salt compound in the preparation of acid-generating agents for corrosion resists.
[0026] This invention also provides the application of the above-described biscarbazolium thioonium salt compound in the preparation of photoinitiators for cationic polymerization.
[0027] The biscarbazolium thioonium salt compound provided by this invention achieves the following innovations by linking biscarbazolium units through sulfur atoms and introducing thioonium salt groups into the molecule: Red shift in absorption wavelength: The conjugation extension effect of biscarbazole enables the maximum absorption wavelength to cover the range of 365–420 nm, which is highly matched with LED light sources; Highly efficient free radical generation: The photolysis pathway of thioonium salts, combined with the electron donor properties of carbazole, significantly improves free radical yield and resistance to oxygen inhibition. The development of this compound provides a novel photoinitiator for the field of photocuring that combines high initiation efficiency, broad spectral response, and environmental friendliness, filling a gap in existing technologies. Detailed Implementation
[0028] This invention provides a compound containing a biscarbazolium thioonium salt, having the structure shown in formula (I): Formula (I); R1 is independently selected from H, alkyl groups with 1 to 50 carbon atoms (substituted or unsubstituted), cycloalkyl groups with 3 to 30 carbon atoms (substituted or unsubstituted), aryl groups with 6 to 50 carbon atoms (substituted or unsubstituted), and heteroaromatic groups with 5 to 60 carbon atoms (substituted or unsubstituted). R2 is independently selected from H, halogen atom, cyano, nitro, alkoxy, haloalkyl, acyl, acyloxy, sulfonyl, substituted or unsubstituted alkyl with 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 30 carbon atoms, substituted or unsubstituted cycloalkyl with 6 to 50 carbon atoms, and substituted or unsubstituted heteroaromatic group with 5 to 60 carbon atoms. R3 is independently selected from H, halogen atom, cyano, nitro, alkoxy, haloalkyl, acyl, acyloxy, sulfonyl, substituted or unsubstituted alkyl with 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 30 carbon atoms, substituted or unsubstituted cycloalkyl with 6 to 50 carbon atoms, and substituted or unsubstituted heteroaromatic group with 5 to 60 carbon atoms. M - X represents - ClO4 - CN - HSO4 - NO3 - CF3COO - (BX4) - (SbX6) - (AsX6) - (PX6) - Al[OC(CF3)3]4 - R4SO3 - (R4SO2)3C - (R4SO2)2N - B(C6X5)4 - Ga(C6X5)4 - In this formula, X represents a halogen, and R4 represents an alkyl group with 1 to 50 carbon atoms, a perfluoroalkyl group with 1 to 50 carbon atoms, an aryl group with 6 to 50 cyclic carbon atoms, or a substituted aryl group.
[0029] In this invention, the biscarbazolylthioonium salt compound is preferably selected from any one of the compounds shown in the following structural formulas:
[0030]
[0031]
[0032]
[0033]
[0034]
[0035]
[0036]
[0037]
[0038]
[0039]
[0040]
[0041]
[0042]
[0043]
[0044] .
[0045] This invention also provides a method for preparing a compound containing a biscarbazolyl thioonium salt, wherein the preparation method is carried out according to the following synthetic route:
[0046] In this invention, the preferred method for synthesizing intermediate A includes: adding 1 equivalent of raw material A, 0.75 equivalents of thionyl chloride, and an appropriate amount of dichloromethane to a 500 mL three-necked flask; cooling in an ice-water bath at approximately 5°C; adding 0.5 equivalents of aluminum trichloride in batches over approximately 1 hour; continuing stirring for 2-8 hours; and monitoring the liquid-phase reaction until complete. The dichloromethane solution of the product is then poured into an appropriate amount of ice water, stirred continuously, and the dichloromethane layer is separated. The dichloromethane layer is washed with water, and the dichloromethane product solution is rotary evaporated to obtain a pale yellow solid, i.e., intermediate A.
[0047] In this invention, the yield of intermediate A is 40-80%.
[0048] In this invention, the preferred method for synthesizing intermediate B includes: adding 1 equivalent of intermediate A and an appropriate amount of acetic anhydride to a 500 mL four-necked flask, stirring in an ice-water bath, controlling the temperature at around 0°C, adding 1 equivalent of concentrated sulfuric acid (70% by mass) dropwise over approximately 1 hour, then adding 1-1.2 equivalents of raw material B in batches to the reaction system, continuing stirring for 8-16 hours, then slowly adding an appropriate amount of deionized ice water, extracting the solution with benzene 2-3 times, separating the aqueous layer, washing the combined benzene layer once with water, and combining the aqueous layers to obtain an aqueous solution of intermediate B.
[0049] In this invention, 1-1.2 equivalents of KPF6 solid are added to the aqueous solution of the above intermediate B for ion exchange. Deionized water is added appropriately while stirring. As KM solid dissolves, the target product gradually precipitates out. The solid is obtained by filtration and drying, and the final product yield is 70-90%.
[0050] The present invention also provides the application of the above-mentioned biscarbazolium thioonium salt compounds in the preparation of photoresist acid generators and photoinitiators for cationic polymerization.
[0051] In this invention, the biscarbazolium thioonium salt compound can release Lewis acid after being excited by energy rays (such as ultraviolet-visible light, electron beam or X-ray), thus having the dual functions of a photoacid generator and a cationic photoinitiator.
[0052] In this invention, the biscarbazolium thioonium salt compound, through molecular structure engineering (introducing a biscarbazolium group), exhibits a significant red-shift in absorption wavelength, making it compatible with 365-405 nm LED light sources and the full spectrum of traditional mercury lamps (including i-line 365 nm and h-line 405 nm). Compared to traditional triphenylthioonium salts (λ_max <300 nm), its photosensitivity is improved by more than 30%, and it is compatible with KrF excimer lasers (248 nm) and ArF lasers (193 nm), making it suitable for photochemical processes in various scenarios from deep ultraviolet to visible light.
[0053] In this invention, the photosensitive composition formed by the biscarbazolium thioonium salt compound and cationic active monomers (such as epoxy resins and vinyl ethers) can cover the following high-value-added fields: Microelectronics manufacturing: As a core component of chemically amplified photoresists, its high acid diffusion control capability and low line edge roughness (LWR) characteristics can meet the precision patterning requirements of 5G chips, IC packaging, etc.; Industrial coating and printing: In UV-LED curable inks, metal can coatings, and flexographic printing, its antioxidant and polymerization-inhibiting properties and low shrinkage rate (<5%) significantly improve coating adhesion and durability; 3D printing and biomedicine: Achieving submicron-level spatial resolution through a two-photon excitation mechanism, suitable for photopolymerization of medical implants and microfluidic chip manufacturing.
[0054] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0055] Example 1 The preparation of compound 1 is described in detail below, and the synthetic route is shown below:
[0056] Synthetic intermediate A1: 16.7 g of starting material 1, 8.9 g of thionyl chloride, and 100 mL of dichloromethane were added to a 500 mL three-necked flask. The mixture was cooled in an ice-water bath at approximately 5 °C. 6.7 g of aluminum trichloride was added in portions over approximately 1 hour, followed by stirring for 2 hours until the reaction was complete. The dichloromethane solution of the product was poured into an appropriate amount of ice water and stirred continuously. The dichloromethane layer was separated, washed with water, and the dichloromethane product solution was rotary evaporated to obtain a pale yellow solid, i.e., intermediate A1, with a yield of 60%. Synthesizing intermediate B1: Add 7.6 g of intermediate A1 and 100 mL of acetic anhydride to a 500 mL four-necked flask, stir in an ice-water bath, maintain the temperature at around 0 °C, and add 2.8 g of concentrated sulfuric acid (70% by mass) dropwise over about 1 hour. After the addition is complete, add 2.2 g of raw material B1 in batches to the reaction system and continue stirring for 12 hours. Then, slowly add an appropriate amount of deionized ice water. Extract the solution with benzene 2-3 times, separate the aqueous layers, combine the benzene layers and wash once with water. Combine the aqueous layers to obtain an aqueous solution of intermediate B1. 3.7 g of KPF6 solid was added to the aqueous solution of the above intermediate B1 for ion exchange. Deionized water was added appropriately while stirring. As the KPF6 solid dissolved, the target product gradually precipitated out. After filtration and drying, the final solid product 1 was obtained with a yield of 72%.
[0057] Example 2 The preparation of compound 2 is described in detail below, and the synthetic route is shown below:
[0058] Synthesizing intermediate A1: 16.8 g of starting material 1, 8.9 g of thionyl chloride, and 100 mL of dichloromethane were added to a 500 mL three-necked flask. The mixture was cooled in an ice-water bath at approximately 5 °C. 6.8 g of aluminum trichloride was added in portions over approximately 1 hour, followed by stirring for 2 hours until the reaction was complete. The dichloromethane solution of the product was poured into a suitable amount of ice water and stirred continuously. The dichloromethane layer was separated, washed with water, and the dichloromethane product solution was rotary evaporated to obtain a pale yellow solid, which is intermediate A1, with a yield of 65%. Synthesizing intermediate B2: Add 7.6 g of intermediate A1 and 100 mL of acetic anhydride to a 500 mL four-necked flask, stir in an ice-water bath, maintain the temperature at around 0 °C, and add 2.8 g of concentrated sulfuric acid (70% by mass) dropwise over about 1 hour. After the addition is complete, add 3.28 g of raw material B2 in batches to the reaction system and continue stirring for 12 hours. Then, slowly add an appropriate amount of deionized ice water. Extract the solution with benzene 2-3 times, separate the aqueous layers, combine the benzene layers and wash once with water. Combine the aqueous layers to obtain an aqueous solution of intermediate B2. 3.9 g of KPF6 solid was added to the aqueous solution of the above intermediate B2 for ion exchange. Deionized water was added appropriately while stirring. As the KPF6 solid dissolved, the target product gradually precipitated out. After filtration and drying, the final solid product 2 was obtained with a yield of 71%.
[0059] Example 3 The preparation of compound 3 is described in detail below, and the synthetic route is shown below:
[0060] Synthetic intermediate A1: 16.8 g of starting material 1, 9.0 g of thionyl chloride, and 100 mL of dichloromethane were added to a 500 mL three-necked flask. The mixture was cooled in an ice-water bath at approximately 5 °C. 6.8 g of aluminum trichloride was added in portions over approximately 1 hour, followed by stirring for 2 hours until the reaction was complete. The dichloromethane solution of the product was poured into an appropriate amount of ice water and stirred continuously. The dichloromethane layer was separated, washed with water, and the dichloromethane product solution was rotary evaporated to obtain a pale yellow solid, i.e., intermediate A1, with a yield of 70%. Synthesizing intermediate B3: Add 7.6 g of intermediate A1 and 100 mL of acetic anhydride to a 500 mL four-necked flask, stir in an ice-water bath, maintain the temperature at around 0 °C, and add 2.8 g of concentrated sulfuric acid (70% by mass) dropwise over about 1 hour. After the addition is complete, add 3.5 g of raw material B3 in batches to the reaction system and continue stirring for 12 hours. Then, slowly add an appropriate amount of deionized ice water. Extract the solution with benzene 2-3 times, separate the aqueous layers, combine the benzene layers and wash once with water. Combine the aqueous layers to obtain an aqueous solution of intermediate B3.
[0061] 3.9 g of KPF6 solid was added to the aqueous solution of the above intermediate B3 for ion exchange. Deionized water was added appropriately while stirring. As the KPF6 solid dissolved, the target product gradually precipitated out. After filtration and drying, the final solid product 3 was obtained with a yield of 68%.
[0062] Example 4 The preparation of compound 4 is described in detail below, and the synthetic route is shown below:
[0063] Synthesizing intermediate A2: 18.3 g of starting material 1, 9.0 g of thionyl chloride, and 100 mL of dichloromethane were added to a 500 mL three-necked flask. The mixture was cooled in an ice-water bath at approximately 5 °C. 6.8 g of aluminum trichloride was added in portions over approximately 1 hour, followed by stirring for 2 hours until the reaction was complete. The dichloromethane solution of the product was poured into a suitable amount of ice water and stirred continuously. The dichloromethane layer was separated, washed with water, and the dichloromethane product solution was rotary evaporated to obtain a pale yellow solid, which is intermediate A2, with a yield of 70%. Synthesizing intermediate B4: Add 8.2 g of intermediate A2 and 100 mL of acetic anhydride to a 500 mL four-necked flask, stir in an ice-water bath, maintain the temperature at around 0 °C, and add 2.8 g of concentrated sulfuric acid (70% by mass) dropwise over about 1 hour. After the addition is complete, add 3.5 g of raw material B4 in batches to the reaction system and continue stirring for 12 hours. Then, slowly add an appropriate amount of deionized ice water. Extract the solution with benzene 2-3 times, separate the aqueous layers, combine the benzene layers and wash once with water. Combine the aqueous layers to obtain an aqueous solution of intermediate B4. 3.9 g of KPF6 solid was added to the aqueous solution of the above intermediate B4 for ion exchange. Deionized water was added appropriately while stirring. As the KPF6 solid dissolved, the target product gradually precipitated out. After filtration and drying, the final solid product 4 was obtained with a yield of 68%.
[0064] Example 5 The preparation of compound 5 is described in detail below, and the synthetic route is shown below:
[0065] Synthesizing intermediate A2: 18.2 g of starting material 2, 8.9 g of thionyl chloride, and 100 mL of dichloromethane were added to a 500 mL three-necked flask. The mixture was cooled in an ice-water bath at approximately 5 °C. 6.8 g of aluminum trichloride was added in portions over approximately 1 hour, followed by stirring for 2 hours until the reaction was complete. The dichloromethane solution of the product was poured into a suitable amount of ice water and stirred continuously. The dichloromethane layer was separated, washed with water, and the dichloromethane product solution was rotary evaporated to obtain a pale yellow solid, i.e., intermediate A2, with a yield of 65%. Synthesizing intermediate B2: Add 8.3 g of intermediate A2 and 100 mL of acetic anhydride to a 500 mL four-necked flask, stir in an ice-water bath, maintain the temperature at around 0 °C, and add 2.8 g of concentrated sulfuric acid (70% by mass) dropwise over about 1 hour. After the addition is complete, add 3.5 g of raw material B2 in batches to the reaction system and continue stirring for 12 hours. Then, slowly add an appropriate amount of deionized ice water. Extract the solution with benzene 2-3 times, separate the aqueous layers, combine the benzene layers and wash once with water. Combine the aqueous layers to obtain an aqueous solution of intermediate B2. 3.9 g of KPF6 solid was added to the aqueous solution of the above intermediate B5 for ion exchange. Deionized water was added appropriately while stirring. As the KPF6 solid dissolved, the target product gradually precipitated out. After filtration and drying, the final solid product 5 was obtained with a yield of 71%.
[0066] Example 6 The preparation of compound 6 is described in detail below, and the synthetic route is shown below:
[0067] Synthesizing intermediate A2: 18.2 g of starting material 2, 8.9 g of thionyl chloride, and 100 mL of dichloromethane were added to a 500 mL three-necked flask. The mixture was cooled in an ice-water bath at approximately 5 °C. 6.8 g of aluminum trichloride was added in portions over approximately 1 hour, followed by stirring for 2 hours until the reaction was complete. The dichloromethane solution of the product was poured into a suitable amount of ice water and stirred continuously. The dichloromethane layer was separated, washed with water, and the dichloromethane product solution was rotary evaporated to obtain a pale yellow solid, which is intermediate A2, with a yield of 69%. Synthesizing intermediate B6: Add 8.3 g of intermediate A2 and 100 mL of acetic anhydride to a 500 mL four-necked flask, stir in an ice-water bath, maintain the temperature at around 0 °C, and add 2.8 g of concentrated sulfuric acid (70% by mass) dropwise over about 1 hour. After the addition is complete, add 3.6 g of raw material B3 in batches to the reaction system and continue stirring for 12 hours. Then, slowly add an appropriate amount of deionized ice water. Extract the solution with benzene 2-3 times, separate the aqueous layers, combine the benzene layers and wash once with water. Combine the aqueous layers to obtain an aqueous solution of intermediate B6. 3.9 g of KPF6 solid was added to the aqueous solution of the above intermediate B6 for ion exchange. Deionized water was added appropriately while stirring. As the KPF6 solid dissolved, the target product gradually precipitated out. After filtration and drying, the final solid product 6 was obtained with a yield of 70%.
[0068] Compound 7-48 can be prepared by referring to the preparation method in Example 1.
[0069] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A compound containing a bis(carbazolyl)thioonium salt, characterized in that, It has the structure shown in equation (I): Equation (I); R1 is independently selected from H, alkyl groups with 1 to 50 carbon atoms (substituted or unsubstituted), cycloalkyl groups with 3 to 30 carbon atoms (substituted or unsubstituted), aryl groups with 6 to 50 carbon atoms (substituted or unsubstituted), and heteroaromatic groups with 5 to 60 carbon atoms (substituted or unsubstituted). R2 is independently selected from H, halogen atom, cyano, nitro, alkoxy, haloalkyl, acyl, acyloxy, sulfonyl, substituted or unsubstituted alkyl with 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 30 carbon atoms, substituted or unsubstituted cycloalkyl with 6 to 50 carbon atoms, and substituted or unsubstituted heteroaromatic group with 5 to 60 carbon atoms. R3 is independently selected from H, halogen atom, cyano, nitro, alkoxy, haloalkyl, acyl, acyloxy, sulfonyl, substituted or unsubstituted alkyl with 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 30 carbon atoms, substituted or unsubstituted cycloalkyl with 6 to 50 carbon atoms, and substituted or unsubstituted heteroaromatic group with 5 to 60 carbon atoms. M - X represents - ClO4 - CN - HSO4 - NO3 - CF3COO - (BX4) - (SbX6) - (AsX6) - (PX6) - Al[OC(CF3)3]4 - R4SO3 - (R4SO2)3C - (R4SO2)2N - B(C6X5)4 - Ga(C6X5)4 - In this formula, X represents a halogen, and R4 represents an alkyl group with 1 to 50 carbon atoms, a perfluoroalkyl group with 1 to 50 carbon atoms, an aryl group with 6 to 50 cyclic carbon atoms, or a substituted aryl group.
2. The compound containing a biscarbazolylthioonium salt according to claim 1, characterized in that, The compound containing the biscarbazoylthioonium salt is selected from any one of the compounds shown in the following structural formulas: .
3. The method for preparing a biscarbazolyl thioonium salt compound according to claim 1 or 2, characterized in that, The preparation method follows the synthetic route described below: .
4. A photosensitizing composition, characterized in that, Including the biscarbazolylthioonium salt compound as described in claim 1 or 2.
5. A UV-curable composition, characterized in that, Including the biscarbazolylthioonium salt compound as described in claim 1 or 2.
6. The use of the biscarbazolium thioonium salt compound according to claim 1 or 2 in the preparation of acid-generating agents for corrosion resists.
7. The use of the biscarbazolium thioonium salt compound according to claim 1 or 2 in the preparation of photoinitiators for cationic polymerization.