High-photosensitive photoinitiator as well as composition and application thereof

Abstract

The invention belongs to the technical field of photosensitive materials, and particularly relates to a high-photosensitive photoinitiator as well as a composition and application thereof. The ortho-position of a benzene ring connected with imidazole is substituted by alkoxy or hydroxyl, and the benzene ring and the connected benzene ring form conjugation, so that the electron transition energy level difference is reduced, the frequency of photons needing to be absorbed is reduced, the corresponding wavelength is increased, the dissolving property of the photoinitiator is improved, and the pattern precision and the resolution are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of photosensitive materials, and in particular relates to a high-sensitivity photoinitiator and a composition and application thereof. Background Art

[0002] Photocuring (also known as photopolymerization) is a green synthesis technology. Under the action of ultraviolet light or visible light, liquid oligomers (including monomers) are polymerized into solid products by photoinitiators. Compared with traditional polymerization methods, photopolymerization has the characteristics of low energy required, environmental friendliness, and easy scale-up of reactions. In recent years, photocuring has attracted more and more attention and has been widely used in dental materials, 3D printing, inks, photoresists and other fields. The general photopolymerization system mainly includes the following three components: (1) oligomers (or prepolymers, prepolymer monomers), which give the material basic physical and chemical properties; (2) monomers, also known as active diluents, which are mainly used to adjust the viscosity of the system, but also affect the curing rate and the performance of the material; (3) photoinitiators, which are used to generate active species (free radicals or cations) that initiate polymerization reactions. Among them, photoinitiators are the most important component in photopolymerization systems, and the research on photoinitiators has always been a hot topic in photopolymerization reactions.

[0003] At present, photoinitiators can be mainly divided into free radical photoinitiators and cationic photoinitiators, among which aromatic biimidazole is a type of free radical photoinitiator, which is mainly used in the fields of photoresist imaging, microlithography, microelectronics industry and large-scale integrated circuit manufacturing. The CN bond connecting two imidazole groups in its molecule breaks after absorbing light, generating two aromatic imidazole free radicals, which are oxidizing and can capture hydrogen from other compounds. Two triaryl imidazole free radicals act simultaneously, which can further improve the efficiency of photoinitiation. However, this type of photoinitiator is insensitive to long-wave ultraviolet light and visible light, or has a very low sensitivity. Therefore, in the prior art, in order to extend its photosensitive wavelength and expand its scope of application, a sensitizer is often used in combination with it, and the control method is complicated and costly. Based on this, the present invention proposes a biimidazole photoinitiator with high efficiency sensitivity. Summary of the invention

[0004] In order to solve the deficiencies of the prior art, the present invention provides a high-sensitivity photoinitiator and a composition and application thereof.

[0005] The technical solution provided by the present invention is as follows:

[0006] A highly sensitive photoinitiator having the structural formula shown in Formula 1:

[0007]

[0008] in:

[0009] R1 is selected from H or C1-10 The alkyl group;

[0010] R2 is selected from H, halogen, cyano, hydroxyl, nitro, C 1-12 Alkyl, C 1-12 At least one of the alkoxy groups; m is a natural integer of 0-4, such as 0, 1, 2, 3, 4;

[0011] Ar1, Ar2, Ar3, Ar4, Ar5 are each independently selected from C 6-30 The aryl group, the C 6-30 The aryl group is substituted by one or more R', wherein R' is selected from hydrogen atoms, halogen, cyano, nitro, hydroxyl, C 1-12 Alkyl, C 2-12 Alkenyl or C 2-12 At least one of the alkoxy groups, Ar1, Ar2, Ar3, Ar4, Ar5 are the same or different.

[0012] In the above technical solution:

[0013] In the biimidazole photosensitive initiator provided by the present invention, the two imidazole rings are not in the same plane, but in the same plane with the three aromatic rings connected thereto, so the absorption of the conjugated double bonds on the biimidazole and benzene ring is significantly red-shifted, increasing the effective absorption wavelength of the initiator;

[0014] The alkoxy or hydroxyl group on the ortho position of the benzene ring connected to the imidazole is substituted, and the conjugation is formed with the adjacent benzene ring, so that the difference in the energy level of electron transition is reduced, the frequency of photons required to be absorbed is reduced, and the corresponding wavelength is increased. At the same time, the solubility of the photoinitiator is increased, and the pattern accuracy and resolution are improved.

[0015] Preferably, the formula 1 has the structural formula shown in 1-1 or 1-2:

[0016]

[0017] The R3 is selected from H, halogen, cyano, nitro, unsubstituted or substituted by one or more R' C 1-12 Alkyl, unsubstituted or substituted by one or more R'C 1-12 Alkoxy, unsubstituted or substituted by one or more R' C 6-18 and when R3 is selected from C 6-18 When the aryl group is an aromatic group, R3 is bonded to or fused with the adjacent benzene ring; p is a natural integer of 0-5.

[0018] In the technical solution of the present application, natural integers from 0 to 5 refer to 0, 1, 2, 3, 4, and 5, and p is preferably 0, 1, and 2; natural integers from 0 to 4 refer to 0, 1, 2, 3, and 4.

[0019] Preferably, the formula 1 has a structure shown in formula 1-3 or 1-4:

[0020]

[0021] R4 is selected from halogen or -OR6, wherein R6 is H or C 1-12 Alkyl; R5 is selected from H, halogen, cyano, nitro, unsubstituted or substituted by one or more R'C 1-12 Alkyl, unsubstituted or substituted by one or more R'C 1-12 Alkoxy, unsubstituted or substituted by one or more R' C 6-18 wherein q is a natural integer of 0-4, for example, 0, 1, 2, 3, 4. Preferably, q is 0, 1 or 2.

[0022] Furthermore, the R4 is the same as -OR1 in Formula 1.

[0023] Preferably, Ar1 is the same as Ar4, Ar2 is the same as Ar3, and Ar1 is the same as or different from Ar2.

[0024] Preferably, the R5 is the same as the R2, and m=q.

[0025] Further, Ar1, Ar2, Ar3, Ar4 are independently selected from the group shown in formula 2

[0026] *-Ar-(R7)a

[0027] Formula 2, wherein * is a connection site; Ar is C 6-18 wherein R7 is selected from halogen, cyano, nitro, unsubstituted or substituted by one or more R'C 1-12 Alkyl, unsubstituted or substituted by one or more R'C 1-12 Alkoxy, unsubstituted or substituted by one or more R' C 6-18 said a is a natural integer of 0-8, for example 0, 1, 2, 3, 4, 5, 6, 7, 8.

[0028] In the technical solution of the present application, a natural integer from 0 to 5 refers to 0, 1, 2, 3, 4, and 5, and a is preferably 0, 1, and 2; a natural integer from 0 to 4 refers to 0, 1, 2, 3, and 4, and b is preferably 0 or 1.

[0029] Furthermore, the formula 2 can be further expressed as:

[0030]

[0031] Preferably, the highly sensitive photoinitiator is selected from any one of the following structural formulas:

[0032]

[0033]

[0034]

[0035]

[0036] The second object of the present invention is to provide a photosensitive composition, which comprises at least one of the above-mentioned high-sensitivity photoinitiators.

[0037] The photosensitive composition can be applied to a photosensitive dry film, which includes a support and a photosensitive layer, wherein the photosensitive layer includes the above-mentioned high-sensitivity photoinitiator. The support is a conventional material in the art, such as polyethylene terephthalate (PET).

[0038] The third object of the present invention is to provide a use of a photosensitive dry film comprising the high-sensitivity photoinitiator of the present application in a photosensitive element.

[0039] In the biimidazole photosensitive initiator provided by the present invention, two imidazole rings are not in the same plane, but in the same plane with three benzene rings connected thereto. Therefore, the absorption of the conjugated double bonds on the biimidazole and the benzene ring is obviously red-shifted, thereby increasing the effective absorption wavelength of the initiator. The alkoxy group on the ortho position of the benzene ring connected to the imidazole is substituted, and the alkoxy group forms a conjugation with the connected benzene ring, thereby reducing the difference in the electron transition energy level, reducing the frequency of the photons required to be absorbed, and increasing the corresponding wavelength. At the same time, the solubility performance of the photoinitiator is increased, thereby improving the pattern accuracy and resolution. DETAILED DESCRIPTION

[0040] The principles and features of the present invention are described below. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention. If no specific conditions are specified in the examples, the conditions are carried out according to conventional conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments is not specified, they are all conventional products that can be obtained commercially.

[0041] Example 1: Compound (3)

[0042] A1 Preparation:

[0043]

[0044] 2-Butoxy-5-nitrobenzaldehyde (0.01 mol, 2.23 g), aromatic aldehyde (0.01 mol, 2.10 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 3.47 g of intermediate A1 with a yield of 84%.

[0045] B1 Preparation:

[0046]

[0047] Benzaldehyde (0.01 mol, 1.06 g), aromatic aldehyde (0.01 mol, 2.10 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was cooled, washed with water until neutral, dried and recrystallized with ethanol to obtain 2.64 g of intermediate B1 with a yield of 89%.

[0048] Preparation of compound (3):

[0049]

[0050] Add 50 ml of toluene solution to a dry round-bottom flask, add intermediate A1 (3.5 mmol, 1.45 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B1 (3.5 mmol, 1.04 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring the reaction is complete, separate the liquids, collect the organic phase, and spin dry to obtain 1.86 g of compound (3), with a yield of 75%. The molecular weight is 707.650 as determined by mass spectrometer (MALDI-TOF-MS), which is confirmed to be the target compound (3).

[0051] Example 2: Compound (10)

[0052] A2 Preparation:

[0053]

[0054] 2-Butoxybenzaldehyde (0.01 mol, 1.78 g), 1-(2-chlorophenyl)-2-phenylethane-1,2-dione (0.01 mol, 2.45 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 3.26 g of intermediate A2 with a yield of 81%.

[0055] Preparation of compound (10):

[0056]

[0057] Add 50 ml of toluene solution to a dry round-bottom flask, add intermediate A2 (3.5 mmol, 1.41 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B1 (3.5 mmol, 1.04 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring the reaction is complete, separate the liquids, collect the organic phase, and spin dry to obtain 1.90 g of compound (10), with a yield of 78%. The molecular weight is 696.365 as determined by mass spectrometer (MALDI-TOF-MS), which is confirmed to be the target compound (10).

[0058] Example 3: Compound (19)

[0059] A3 Preparation:

[0060]

[0061] 2-Butoxybenzaldehyde (0.01 mol, 1.78 g), 1-(3,4-dimethoxyphenyl)-2-phenylethane-1,2-dione (0.01 mol, 2.70 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 3.56 g of intermediate A3 with a yield of 83%.

[0062] B3 Preparation:

[0063]

[0064] Benzaldehyde (0.01 mol, 1.06 g), 1-(3,4-dimethoxyphenyl)-2-phenylethane-1,2-dione (0.01 mol, 2.70 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 3.03 g of intermediate B3 with a yield of 85%.

[0065] Preparation of compound (19):

[0066]

[0067] Add 50 ml of toluene solution to a dry round-bottom flask, add intermediate A3 (3.5 mmol, 1.50 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B3 (3.5 mmol, 1.25 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring the reaction is complete, separate the liquids, collect the organic phase, and spin dry to obtain 2.08 g of compound (19), with a yield of 76%. The molecular weight was determined by mass spectrometry (MALDI-TOF-MS) to be 782.851, which was confirmed to be the target compound (19).

[0068] Example 4: Compound (24)

[0069] A4 Preparation:

[0070]

[0071] 2-Hydroxybenzaldehyde (0.01 mol, 1.22 g), aromatic aldehyde (0.01 mol, 2.10 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 2.75 g of intermediate A4 with a yield of 88%.

[0072] Preparation of compound (24):

[0073]

[0074] Add 50 ml of toluene solution to a dry round-bottom flask, add intermediate A4 (3.5 mmol, 1.09 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B1 (3.5 mmol, 1.04 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring the reaction is complete, separate the liquids, collect the organic phase, and spin dry to obtain 1.64 g of compound (24), with a yield of 77%. The molecular weight is 606.628 as determined by mass spectrometer (MALDI-TOF-MS), which is confirmed to be the target compound (24).

[0075] Example 5: Compound (29)

[0076] A5 Preparation:

[0077]

[0078] 2-Ethoxybenzaldehyde (0.01 mol, 1.50 g), 1,2-di(phenanthrene-9-yl)ethane-1,2-dione (0.01 mol, 4.10 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 4.38 g of intermediate A5 with a yield of 81%.

[0079] Preparation of compound (29):

[0080]

[0081] In a dry round-bottom flask, add 50 ml of toluene solution, add intermediate A5 (3.5 mmol, 1.89 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B1 (3.5 mmol, 1.04 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring, separate the liquids after the reaction is complete, collect the organic phase, and spin dry to obtain 2.10 g of compound (29), with a yield of 72%. The molecular weight was determined by mass spectrometry (MALDI-TOF-MS) to be 834.746, which was confirmed to be the target compound (29).

[0082] Example 6: Compound (34)

[0083] A6 Preparation:

[0084]

[0085] 2-Propoxybenzaldehyde (0.01 mol, 1.64 g), aromatic aldehyde (0.01 mol, 2.10 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 3.08 g of intermediate A6 with a yield of 87%.

[0086] B6 Preparation:

[0087]

[0088] 2-Chlorobenzaldehyde (0.1 mol, 1.41 g), aromatic aldehyde (0.01 mol, 2.10 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 2.94 g of intermediate B6 with a yield of 89%.

[0089] Preparation of compound (34):

[0090]

[0091] In a dry round-bottom flask, add 50 ml of toluene solution, add intermediate A6 (3.5 mmol, 1.24 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B6 (3.5 mmol, 1.16 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring, separate the liquids, collect the organic phase, and spin dry to obtain 1.82 g of compound (34), with a yield of 76%. The molecular weight was determined by mass spectrometry (MALDI-TOF-MS) to be 682.832, which was confirmed to be the target compound (34).

[0092] Example 7: Compound (35)

[0093] A7 Preparation:

[0094]

[0095] 2-Hexyloxybenzaldehyde (0.01 mol, 2.06 g), aromatic aldehyde (0.01 mol, 2.10 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry 150 ml round-bottom flask, and heated to 90°C under nitrogen protection, and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried, and recrystallized with ethanol to obtain 3.29 g of intermediate A7 with a yield of 83%;

[0096] B7 Preparation:

[0097]

[0098] 2-Propoxybenzaldehyde (0.1 mol, 1.64 g), aromatic aldehyde (0.01 mol, 2.10 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 3.01 g of intermediate B7 with a yield of 85%.

[0099] Preparation of compound (35):

[0100]

[0101] Add 50 ml of toluene solution to a dry round-bottom flask, add intermediate A7 (3.5 mmol, 1.39 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B7 (3.5 mmol, 1.24 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring the reaction is complete, separate the liquids, collect the organic phase, and spin dry to obtain 2.02 g of compound (35), with a yield of 77%. The molecular weight was determined by mass spectrometry (MALDI-TOF-MS) to be 748.547, which was confirmed to be the target compound (35).

[0102] Example 8: Compound (40)

[0103] B8 Preparation:

[0104]

[0105] In a dry round-bottom flask, 2-methoxybenzaldehyde (0.01 mol, 1.36 g), 1-(2-chlorophenyl)-2-phenylethane-1,2-dione (0.01 mol, 2.45 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added. The mixture was protected by nitrogen and heated to 90°C. The mixture was refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 3.18 g of intermediate B8 with a yield of 88%.

[0106] Preparation of compound (40):

[0107]

[0108] Add 50 ml of toluene solution to a dry round-bottom flask, add intermediate A2 (3.5 mmol, 1.41 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B8 (3.5 mmol, 1.26 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring the reaction is complete, separate the liquids, collect the organic phase, and spin dry to obtain 2.0 g of compound (40), with a yield of 75%. The molecular weight is 761.053 as determined by mass spectrometer (MALDI-TOF-MS), which is confirmed to be the target compound (40).

[0109] Example 9: Compound (50)

[0110] A9 Preparation:

[0111]

[0112] 2-Butoxy-5-nitrobenzaldehyde (0.01 mol, 2.23 g), 1-(3,4-dimethoxyphenyl)-2-phenylethane-1,2-dione (0.01 mol, 2.70 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 3.88 g of intermediate A9 with a yield of 82%.

[0113] B9 Preparation:

[0114]

[0115] 2-Chlorobenzaldehyde (0.01 mol, 1.41 g), 1-phenyl-2-(m-tolyl)ethane-1,2-dione (0.01 mol, 2.24 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 2.93 g of intermediate B9 with a yield of 85%.

[0116] Preparation of compound (50):

[0117]

[0118] In a dry round-bottom flask, add 50 ml of toluene solution, add intermediate A9 (3.5 mmol, 1.66 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B9 (3.5 mmol, 1.21 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring, separate the liquids, collect the organic phase, and spin dry to obtain 2.23 g of compound (50), with a yield of 78%. The molecular weight was determined by mass spectrometry (MALDI-TOF-MS) to be 816.112, which was confirmed to be the target compound (50).

[0119] Example 10: Compound (51)

[0120] B10 Preparation:

[0121]

[0122] 2-Chlorobenzaldehyde (0.01 mol, 1.41 g), 1-(3,4-dimethoxyphenyl)-2-phenylethane-1,2-dione (0.01 mol, 2.70 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 3.40 g of intermediate B10 with a yield of 87%. Preparation of compound (51):

[0123]

[0124] Add 50 ml of toluene solution to a dry round-bottom flask, add intermediate A9 (3.5 mmol, 1.66 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate B10 (3.5 mmol, 1.37 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring, separate the liquids, collect the organic phase, and spin dry to obtain 2.32 g of compound (51), with a yield of 77%. The molecular weight was determined by mass spectrometry (MALDI-TOF-MS) to be 861.890, which was confirmed to be the target compound (51).

[0125] Example 11: Compound (59)

[0126] Preparation of compound (59):

[0127]

[0128] Add 50 ml of toluene solution to a dry round-bottom flask, add intermediate A9 (3.5 mmol, 1.66 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, dissolve intermediate A1 (3.5 mmol, 1.45 g) in 50 ml of toluene solution, mix and stir the two solutions, reflux for 5 h, and after TCL monitoring the reaction is complete, separate the liquids, collect the organic phase, and spin dry to obtain 2.32 g of compound (59), with a yield of 75%. The molecular weight is 884.623 as determined by mass spectrometer (MALDI-TOF-MS), which is confirmed to be the target compound (59).

[0129] Example 12: Compound (64)

[0130] A12 Preparation:

[0131]

[0132] 2-Butoxy-5-nitrobenzaldehyde (0.01 mol, 2.23 g), 1-(2-chlorophenyl)-2-(3,5-dimethoxyphenyl)ethane-1,2-dione (0.01 mol, 3.05 g), ammonium acetate (0.2 mol, 15.42 g) and 50 ml of acetic acid were added to a dry round-bottom flask, and the mixture was heated to 90°C under nitrogen protection and refluxed for 3 h. After the reaction was completed as monitored by TCL, the mixture was washed with water until neutral, dried and recrystallized with ethanol to obtain 4.37 g of intermediate A12 with a yield of 86%.

[0133] Preparation of compound (64):

[0134]

[0135] In a dry round-bottom flask, add 50 ml of toluene solution, add intermediate A12 (7 mmol, 3.56 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, and reflux for 5 h. After the reaction is complete as monitored by TCL, separate the liquids, collect the organic phase, and spin dry to obtain 5.25 g of compound (64), with a yield of 74%. The molecular weight was determined by mass spectrometry (MALDI-TOF-MS) to be 1012.917, which was confirmed to be the target compound (64).

[0136] Example 13: Compound (77)

[0137]

[0138] In a dry round-bottom flask, add 50 ml of toluene solution, add intermediate A9 (7 mmol, 3.31 g), potassium ferrocyanide (70 mmol, 23.05 g), and 7.6 g of potassium hydroxide, stir and dissolve evenly, and reflux for 5 hours. After the reaction is complete as monitored by TCL, separate the liquids, collect the organic phase, and spin dry to obtain 4.96 g of compound (77), with a yield of 75%. The molecular weight is 944.972 as determined by mass spectrometry (MALDI-TOF-MS), which is confirmed to be the target compound (77).

[0139] Comparative Examples 1-3:

[0140]

[0141] Performance testing:

[0142] Maximum absorption wavelength: Weigh a certain amount of the photoinitiators prepared in Examples 1-13 and Comparative Examples 1-3 and dissolve them in dichloromethane to a concentration of 1×10 -5 mol / L solution, and measure the UV absorption spectrum of the solution at 25°C;

[0143] Solubility: Taking propylene glycol methyl ether acetate (PGMEA), a widely used active diluent in the field, as an example, the maximum weight that can be dissolved in 100g of solvent at 25°C is used as the evaluation standard for the photoinitiator of the present invention;

[0144] Sensitivity:

[0145] Preparation of photosensitive dry film: 200 ml of PGMEA and 1.5 g of azobisisobutyronitrile were placed in a 500 ml polymerization container, and acrylic acid monomers with 40 wt% solids were added in a molar ratio of 20:20:40:20 for methacrylic acid, glycidyl methacrylate, methyl methacrylate, and dicyclopentyl acrylate, and then stirred and polymerized at 70° C. for 5 hours under a nitrogen atmosphere to prepare an acrylic acid polymer. 50 wt% of acrylic acid polymer, 30 wt% of solvent, 5 wt% of the compound of the present invention as a photopolymerization initiator, 1.5 wt% of 2-mercaptobenzoxazole, and 0.5 wt% of colorless crystal violet were placed in a reaction mixing tank with a UV protective cover and a stirrer in sequence, and stirred at room temperature to prepare a photopolymerizable composition, which was filtered through a 100 mesh screen and evenly coated on a PET film with a coater, and the solvent was dried to prepare a photosensitive dry film with a film thickness of 30 μm, covered with a 23 μm thick polyethylene protective film, and placed at 25° C. for 8 hours;

[0146] The surface of the copper clad laminate was polished to remove the polyethylene protective film on the surface of the photosensitive dry film. The dry film resist was laminated on the copper clad laminate using a laminator at a speed of 1.2 m / min and a roller temperature of 105°C. The sensitivity was measured using a 41-level Stouffer exposure ruler. Twice the shortest developing time was used as the residence time in the developing machine chamber. The level that retains at least 50% of the photopolymer is the maintenance level, which is recorded as the sensitivity. The exposure energy required for a sensitivity of level 23 is the photosensitivity.

[0147] The test results are shown in Table 1 below:

[0148] Table 1

[0149]

[0150]

[0151] As can be seen from the above table, the absorption spectrum of the ortho-alkoxy-substituted bisimidazole photoinitiator provided by the present invention has a significant red shift, and maintains good photosensitivity and solubility. When used in a photosensitive resin photoresist composition, it can effectively improve the photosensitivity, sensitivity, resolution and film removal performance of the photoresist. For example, it has obvious advantages over ortho-chloro.

[0152] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A highly sensitive photoinitiator, characterized in that: It has the structural formula shown in Formula 1: in: R1 is selected from H or C 1-10 The alkyl group; R2 is selected from H, halogen, cyano, hydroxyl, nitro, C 1-12 Alkyl, C 1-12 At least one of the alkoxy groups; m is a natural integer of 0-4; Ar1, Ar2, Ar3, Ar4, Ar5 are each independently selected from C 6-30 The aryl group, the C 6-30 The aryl group is substituted by one or more R', wherein R' is selected from hydrogen atoms, halogen, cyano, nitro, hydroxyl, C 1-12 Alkyl, C 2-12 Alkenyl or C 2-12 At least one of the alkoxy groups, Ar1, Ar2, Ar3, Ar4, Ar5 are the same or different.

2. The high-sensitivity photoinitiator according to claim 1, characterized in that: The formula 1 is selected from the structural formula shown in the following formula 1-1 or 1-2: wherein R3 is selected from H, halogen, cyano, nitro, unsubstituted or substituted by one or more R' C 1-12 Alkyl, unsubstituted or substituted by one or more R'C 1-12 Alkoxy, unsubstituted or substituted by one or more R' C 6-18 and when R3 is selected from C 6-18 When the aryl group is an aromatic group, R3 is bonded to or fused with the adjacent benzene ring; p is a natural integer of 0-5.

3. The high-sensitivity photoinitiator according to claim 1, characterized in that: The formula 1 is selected from the structural formula shown in the following formula 1-3 or 1-4: Wherein, R4 is selected from halogen or -OR6, and R6 is H or C 1-12 Alkyl; said R5 is selected from H, halogen, cyano, nitro, unsubstituted or substituted by one or more R' C 1-12 Alkyl, unsubstituted or substituted by one or more R'C 1-12 Alkoxy, unsubstituted or substituted by one or more R' C 6-18 wherein q is a natural integer of 0-4.

4. The high-sensitivity photoinitiator according to claim 3, characterized in that: The R5 is the same as the R2, and m=q.

5. The high-sensitivity photoinitiator according to claim 1, characterized in that: The Ar1, Ar2, Ar3, and Ar4 are independently selected from the group shown in Formula 2: *-Ar-(R7)a Formula 2; Wherein, * is the connection site; Ar is C 6-18 wherein R7 is selected from halogen, cyano, nitro, unsubstituted or substituted by one or more R'C 1-12 Alkyl, unsubstituted or substituted by one or more R'C 1-12 Alkoxy, unsubstituted or substituted by one or more R' C 6-18 wherein a is a natural integer of 0-8.

6. The high-sensitivity photoinitiator according to claim 5, characterized in that: The formula 2 is selected from the following structural formula: Wherein, a is a natural integer from 0 to 5.

7. The high-sensitivity photoinitiator according to claim 1, characterized in that: Ar1 is the same as Ar4; Ar2 is the same as Ar3; The Ar1 and the Ar2 are the same as or different from each other.

8. The high-sensitivity photoinitiator according to claim 1, characterized in that: The highly sensitive photoinitiator is selected from any one of the following structural formulas:

9. A photosensitive composition, characterized in that: At least comprising the high-sensitivity photoinitiator according to any one of claims 1 to 8.

10. A use of the high-sensitivity photoinitiator according to any one of claims 1 to 8, characterized in that: Used to prepare photosensitive elements.

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