Photosensitive resin composition containing anthrylmethyl quaternary ammonium salt photosensitizer and use thereof

Abstract

The application provides a photosensitive resin composition containing an anthracene methyl quaternary ammonium salt photosensitizer and application thereof, the photosensitizer has a quaternary ammonium group substituted methylene introduced at 10 and / or 9 positions of the anthracene ring, and an acid radical or halogen is used as a counter anion; compared with a commercially available anthracene photosensitizer, the photosensitizer has excellent fat solubility and good water solubility by introducing the quaternary ammonium salt on the premise of retaining photobleaching, brings great potential for formula design of the photosensitive composition, and can greatly reduce developing waste in a later developing process; and can be widely applied in the fields of dry films, paints, coatings, inks and molding materials and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of photosensitive resin, and particularly relates to a photosensitive resin composition containing anthrylmethyl quaternary ammonium salt photosensitizer and application thereof. BACKGROUND

[0002] Photosensitive resin composition is widely used in the field of printed circuit board (PCB), lead frame (LF) and semiconductor packaging (IC) substrate printed circuit board manufacturing as a key pattern transfer material. Among them, the photosensitive resin composition is usually coated on the surface of the PET support film, and after drying, a protective layer such as a polyethylene film (PE) protective layer is closely attached to the surface to form a photosensitive dry film (or dry film resist). In the process of realizing pattern transfer, first, the dry film resist is attached to the copper substrate, a mask with a certain pattern is covered on the dry film resist, and pattern exposure is performed; then, the unexposed part is removed by using a weak alkaline aqueous solution as a developing solution, and etching or electroplating treatment is performed to form a pattern; finally, the dry film solidified part is removed by stripping with a film stripping solution, thereby realizing pattern transfer.

[0003] With the development of electronic devices towards miniaturization and high density, the fineness requirement of the circuit is continuously improved. In order to meet the needs of fine line manufacturing, the photosensitive resin composition needs to have higher resolution. In order to improve the resolution, appropriate sensitizers need to be added to the photosensitive resin composition. For photosensitive resin composition, a suitable photoinitiating system has a direct impact on photosensitivity, resolution and production yield.

[0004] At present, small molecule anthracene derivatives represented by 9,10-dibutoxyanthracene (DBA), 9,10-diacetoxyanthracene (DAcOA) and 9,10-diphenylanthracene (DPHA) are widely used as photosensitizers. Generally, in order to obtain higher photosensitivity and resolution, such photosensitizers need to be used in combination with 2,4,5-triaryl imidazole dimer (HABI) (such as patent CN101568883B); however, such photosensitizer / photoinitiator combination system usually faces the following problems:

[0005] 1) Short-chain alkoxy anthracene derivatives (similar to DBA) with superior solubility, due to their initiation mechanism, the fragments after initiation are prone to migrate in the dry film, penetrate to the surface of the polyethylene (PE) protective film to form crystals, thereby causing short circuit, open circuit and other defects of the resist pattern, or causing the risk of photosensitivity decline due to the penetration of photosensitizer from the photosensitive layer;

[0006] 2) 9,10-dioxyacyl anthracene photosensitizer (DAcOA) due to the electron-withdrawing induction effect of acyloxy group, resulting in the increase of electron cloud density of anthracene ring 9,10, so that the efficiency of the photosensitizer in catalytic curing reaction is reduced, the verticality of the cured photosensitive resin composition sidewall is poor, and the length difference between the top and bottom lines is large to form an "inverted trapezoidal" problem, and the energy required for the exposure of the light initiator is increased, and the photobleaching efficiency is reduced;

[0007] 3) DPHA has the advantage of high light quantum yield, but due to the too large conjugated system and high rigidity of the molecule, the solubility is poor;

[0008] 4) DBA, DAcOA and DPHA and other anthracene photosensitizers are all liposoluble small organic molecule compounds, and they are not water-soluble, and the direct consequence is that the liposoluble photosensitizer and its fragments are easy to aggregate and produce precipitates in the developing process in the aqueous developing solution, easy to adhere to the surface of the copper plate, causing residual copper or short circuit and other problems, affecting the product yield.

[0009] Therefore, it is a technical problem to be solved in the art to develop a new light initiation system with good liposolubility and water solubility, low migration, photobleaching characteristics and excellent developing compatibility, and to construct a high-performance photocuring resin composition based on it. SUMMARY

[0010] Therefore, the purpose of the present application is to overcome the above-mentioned defects existing in the prior art, and to provide an anthracene photosensitizer with small electroplating pollution, high light initiation efficiency, and simple process and low cost, a photosensitive resin composition and its application.

[0011] The present application achieves the above-mentioned purpose by providing a photosensitive resin composition comprising an anthracene methylene quaternary ammonium salt photosensitizer, a photosensitive resist and a photosensitive dry film comprising the photosensitive resin composition, and the application of the photosensitive dry film in printed circuit boards, lead frames, semiconductor packaging substrates, solar cells and photocuring inks. The photosensitizer of the present application can improve the compatibility of the existing dry film product, reduce the migration of the initiator to the PE film, and also can greatly reduce the generation of developing garbage and improve the product yield.

[0012] The present application finds the following problems through a large amount of literature research and experimental research, and proposes an innovative improvement scheme:

[0013] Anthracene compounds or anthracene derivatives can undergo dimerization under the action of light, thus being photobleached. This feature effectively avoids the problem of excessive energy absorption by the upper photosensitizer during exposure, and promotes the bottom photosensitive resin composition to receive more light, so that the photosensitive resin composition can be uniformly cured during exposure, achieving better resolution. For example, patent CN101218538B discloses 9,10-dialkoxy anthracene photosensitizer, CN110446976B discloses alkoxy anthracene or phenyl anthracene photosensitizer, CN116300313A discloses 9,10-dialkoxy anthracene or 9,10-diphenyl anthracene photosensitizer. The above anthracene photosensitizers have good resolution and adhesion.

[0014] However, the present application finds that the 9,10-dialkoxy anthracene photosensitizer will break the 9,10 C-O bond during exposure, and the anthracene ring will dimerize, releasing small molecule alkoxy fragments. These small molecule fragments will migrate from the cured photosensitive resin composition to the plating solution during the subsequent plating process, causing pollution and affecting the life of the plating solution and the plating effect. Due to the electron-withdrawing inductive effect of acyloxy group, the electron cloud density of anthracene ring at 9,10 position increases, so the curing efficiency of 9,10-dialkoxy anthracene (DAcOA) photosensitizer is reduced, the verticality of the side wall of the cured photosensitive resin composition is poor, and the length difference between the top and bottom lines is large, forming an "inverted trapezoidal" problem. In addition, the energy required for exposure of this type of photoinitiator is increased, and the photobleaching efficiency is reduced. Due to the rigid molecular structure of 9,10-dialkoxy anthracene photosensitizer, its solubility is greatly reduced, which has a great influence on the uniformity and consistency of the product.

[0015] In addition, the present application also finds that DBA, DAcOA and DPHA anthracene photosensitizers are liposoluble small molecule organic photosensitizers, which cannot be dissolved in water. However, in most cases, the development process is usually carried out in Na2CO3 aqueous solution, so the direct consequence is that the liposoluble photosensitizer and its fragments are easy to aggregate and produce precipitates in the aqueous developing solution during the development process, which adhere to the surface of the copper plate, causing problems such as copper residue or short circuit, affecting the product yield.

[0016] Based on the above findings, the present application proposes an anthracene methylene quaternary ammonium salt photosensitizer and a photosensitive resin composition suitable therefor, to improve the compatibility of the existing dry film product, reduce the migration of the initiator to the PE film, and also greatly reduce the generation of development waste, improve the product yield.

[0017] (I) Photosensitive resin composition

[0018] A first aspect of the present invention provides a photosensitive resin composition, comprising the following components based on 100 parts by mass of the photosensitive resin composition: an alkali-soluble resin A: 50 to 65 parts; a photopolymerization monomer B: 35 to 50 parts, which is selected from a monomer containing an ethylenically unsaturated double bond; a photoinitiator C: 2 to 5 parts, which is selected from a bis-imidazole compound; and a photosensitizer D: 0.1 to 1 part, wherein the photosensitizer D is an anthracene-10-methylene monocationic quaternary ammonium salt having a structure represented by Formula (I) and / or an anthracene-9,10-dimethylene diquaternary ammonium salt having a structure represented by Formula (II):

[0019]

[0020] Formula (I) Formula (II)

[0021] wherein R a , R b , R c in Formula (I) and R d , R e , R f , R g , R h and R i are each independently selected from one of hydrogen and C1-C12 alkyl;

[0022] R1, R2, R3, R4, R5, R6, R7 and R8 in Formula (I) and Formula (II) are each independently selected from hydrogen, halogen, C1-C12 alkyl, C1-C12 alkoxy, C6-C12 aryl, C6-C12 aryl substituted by one or more halogens, C6-C12 aryl substituted by one or more C1-C12 alkyl groups, C6-C12 aryl substituted by one or more C1-C12 alkoxy groups, C6-C12 aryloxy, C6-C12 aryloxy substituted by one or more halogens, C6-C12 aryloxy substituted by one or more C1-C12 alkyl groups, C6-C12 aryloxy substituted by one or more C1-C12 alkoxy groups;

[0023] R9 in Formula (I) is selected from hydrogen, C1-C12 alkyl, C1-C12 alkoxy, C6-C12 aryl, C6-C12 aryl substituted by one or more C1-C12 alkyl groups, C6-C12 aryl substituted by one or more C1-C12 alkoxy groups, C6-C12 aryloxy, C6-C12 aryloxy substituted by one or more C1-C12 alkyl groups, C6-C12 aryloxy substituted by one or more C1-C12 alkoxy groups;

[0024] X in Formula (I) and Formula (II) is selected from one of halogen, nitrate, acetate, sulfate, triflate, fluoroborate, fluorantimonate.

[0025] Optionally, any two of R in the moiety a , R b and R c in the moiety

[0026] Optionally, any two of R in the moiety d , R e and R f in the moiety

[0027] Optionally, any two of R in the moiety g , R h and R i in the moiety

[0028] According to the present application, the photosensitive resin composition is photocured by the following photoinitiated free radical polymerization mechanism: the anthracene-9-methylene monoquaternary ammonium salt of the structure of Formula (I) and / or the anthracene-9,10-dimethylene diquaternary ammonium salt of the structure of Formula (II) is excited by visible light to generate anthracene radicals, which initiates homolytic cleavage of the bis-imidazole compound to generate imidazole radicals, which activate the monomer containing an olefinically unsaturated double bond to crosslink and cure.

[0029] The term "bis-imidazole compound" as used herein refers to a compound containing two imidazole rings, which are optionally substituted at each position with a substituent.

[0030] As used herein, the term "alkyl" includes saturated aliphatic hydrocarbons, both straight- chain and branched. In some embodiments, alkyl groups have 1 to 20 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, or 1 to 4 carbon atoms. For example, the term "Ci-C2alkyl", as well as the alkyl portion of other groups mentioned herein (e.g., Ci-C2alkoxy), refers to a straight chain or branched chain group having 1 to 12 carbon atoms (e.g., methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, or n-hexyl).

[0031] As used herein, the term "aryl" can include all carbon monocyclic or fused ring polycyclic aromatic groups having a conjugated pi-electron system. "C6-C12aryl" in the term "C6-C12aryl" means that the aryl group has 6 or 12 carbon atoms in the ring(s). Most commonly, aryl groups have 6 carbon atoms in the ring. For example, as used herein, the term "C6-C12aryl" means an aromatic group containing 6 to 12 carbon atoms, such as phenyl or naphthyl.

[0032] As used herein, the term "aryloxy" refers to all carbon monocyclic or fused ring polycyclic aromatic groups having a conjugated pi-electron system attached through an oxygen atom. "C6-C12" in "C6-C12 aryloxy" means that the aryl portion of the aryloxy group has 6 to 12 carbon atoms in the ring (or rings). Most commonly, the aryl portion of the aryloxy group has 6 carbon atoms in the ring. For example, as used herein, the term "C6-C12 aryloxy" refers to aryloxy groups in which the aryl portion contains 6 to 12 carbon atoms, such as phenoxy (-OC6H5) or naphthoxy (-OC10H7). 10 H7).

[0033] Alkali-soluble resin A

[0034] According to the present application, the alkali-soluble resin A is an acrylate copolymer containing aromatic groups. From the perspective of improving the resolution and chemical resistance of the product, it is preferable that the copolymerization ratio of the comonomer having an aromatic group be 50-70% based on the total mass of the comonomers in the copolymerization process.

[0035] In some embodiments of the present application, the alkali-soluble resin is obtained by copolymerization of one or more of (meth)acrylic acid, alkyl (meth)acrylate, benzyl (meth)acrylate, benzyl (meth)acrylate derivatives, phenyl (meth)acrylate, styrene, and styrene derivatives.

[0036] In some embodiments of the present application, the alkali-soluble resin is obtained by copolymerization of (meth)acrylic acid and a copolymerization unit selected from one or more of methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, hydroxyethyl (meth)acrylate, and styrene.

[0037] In some specific embodiments of the present application, the copolymerization monomers of the alkali-soluble resin include methacrylic acid, methyl methacrylate, hydroxyethyl methacrylate, benzyl methacrylate, and styrene.

[0038] Further, the weight average molecular weight of the alkali-soluble resin is 20,000-60,000, the resin acid value is 160-220 mg KOH / g, and the molecular weight distribution index is 1.0-3.0.

[0039] In embodiments of the present application, the content of the alkali-soluble resin is 50-65 parts by mass, and preferably 55-60 parts by mass. If the content is less than 50 parts by mass, there is a tendency for the resist layer to flow, and if the content exceeds 65 parts by mass, there is a tendency for the resolution to decrease.

[0040] Photopolymerizable monomer B

[0041] According to the present application, the photopolymerizable monomer B is selected from monomers containing an ethylenically unsaturated double bond, preferably from ethylenically unsaturated carboxylic acids and / or ethylenically unsaturated carboxylic acid esters, more preferably from (meth)acrylate monomers.

[0042] In a preferred embodiment of the present application, the photopolymerizable monomer is selected from one or more of methoxypolyethylene glycol monoacrylate, ethoxy(propoxy) nonylphenol acrylate, ethoxy(propoxy) bisphenol A di(meth)acrylate, ethoxy(propoxy) di(meth)acrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, ethoxy(propoxy) trimethylolpropane tri(meth)acrylate, di(trimethylolpropane) tetraacrylate, ethoxy(propoxy) pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate.

[0043] In an embodiment of the present application, the content of the photopolymerizable monomer can be 35 to 50 parts by mass, preferably 40 to 50 parts by mass, more preferably 45 to 50 parts by mass. If the content is less than 35 parts by mass, there is a tendency for the sensitivity and the resistance of the resist to decrease, and if the content exceeds 50 parts by mass, there is a tendency for the photopolymerizable resin composition to be difficult to filmize and for the resist layer to flow.

[0044] Photoinitiator C

[0045] According to the present application, the photoinitiator C can be selected from bisimidazole compounds, preferably from 2,4,5-triaryl imidazole dimers.

[0046] In a preferred embodiment of the present application, the photoinitiator is selected from one or more of 2-(2-chlorophenyl)-4,5-diphenyl imidazole dimer, 2-(2-chlorophenyl)-4,5-di(methoxyphenyl) imidazole dimer, 2-(2-fluorophenyl)-4,5-diphenyl imidazole dimer, 2-(2-methoxyphenyl)-4,5-diphenyl imidazole dimer, 2-(4-methoxyphenyl)-4,5-diphenyl imidazole dimer, 2,2',4-tri(2-chlorophenyl)-5-(3,4-dimethoxyphenyl)-4',5'-diphenyl-1,1'-biimidazole.

[0047] In an embodiment of the present application, the content of the photoinitiator can be 2 to 5 parts by mass, preferably 2 to 4 parts by mass, more preferably 2.5 to 3.5 parts by mass. If the content is less than 2 parts by mass, there is a tendency for the sensitivity and the resolution of the resist to decrease, and if the content exceeds 5 parts by mass, there is a tendency for the amount of development waste to increase.

[0048] Photosensitizer D

[0049] According to the present application, a photosensitive resin composition is provided, wherein the photosensitizer D is an anthracene-10-methylene monoquaternary ammonium salt having the structure shown in formula (I) and / or an anthracene-9,10-dimethylene diquaternary ammonium salt having the structure shown in formula (II):

[0050]

[0051] Formula (I) Formula (II)

[0052] wherein each substituent is as defined above.

[0053] In a preferred embodiment according to the present application, X in formula (I) and formula (II) is selected from the group consisting of halogen and nitrate, more preferably halogen.

[0054] In a preferred embodiment according to the present application, R1, R2, R3, R4, R5, R6, R7 and R8 in formula (I) and formula (II) are each independently selected from the group consisting of hydrogen, halogen, C1-C12 alkyl, more preferably hydrogen.

[0055] In some embodiments according to the present application, R9 in formula (I) is selected from the group consisting of hydrogen, C1-C12 alkyl, more preferably hydrogen.

[0056] As can be seen from the above structural formulae, in the anthracene-10-methylene monoquaternary ammonium salt of formula (I) and the anthracene-9,10-dimethylene diquaternary ammonium salt of formula (II), a methylene substituted with a quaternary ammonium group is introduced at the 10 position and / or the 9 position of anthracene, and the counter ion is a negative acid ion or halogen. Compared to existing anthracene photosensitizers, the introduction of the cation-anion pair ensures the water solubility of the structure; at the same time, due to the presence of the quaternary ammonium salt ion containing an alkyl group, the liposolubility of the ionic compound is also ensured. In addition, compared to existing DBA photosensitizers, no small molecule fragments are generated, and the compounds can be widely used in the fields of dry films, paints, coatings, inks and molding materials, etc.

[0057] In exemplary embodiments of the present application, the photosensitizer is anthracene-10-methylene trimethylammonium chloride (TM1) or anthracene-9,10-dimethylene hexamethyl-diammonium dichloride (TM2).

[0058] In specific exemplary embodiments of the present application, the photosensitizer can have one of the following structures:

[0059]

[0060] TM1 TM2

[0061] In the embodiments of the present application, the content of the photosensitizer can be 0.1-1 parts by mass, preferably 0.1-0.8 parts by mass, and more preferably 0.2-0.5 parts by mass. If the content is less than 0.1 parts by mass, the sensitivity of the resist tends to decrease, and if the content exceeds 1 parts by mass, the bottom layer of the resist tends to be incompletely cured, resulting in a "reversed trapezoidal" cross-sectional shape of the resist and poor resolution.

[0062] The preparation strategy of anthracene-10-methylene quaternary ammonium salt of formula (I) and anthracene-9,10-dimethylene diquaternary ammonium salt of formula (II) of the present application can be universally derived by typical synthetic routes of examples. For example, it can be obtained by reacting 10-chloromethyl anthracene or 9,10-dichloromethyl anthracene with a tertiary amine. The typical reaction operation is as follows: under a nitrogen atmosphere, a round-bottom flask equipped with a magnetic stirrer is charged with a dry methanol solution of 10-chloromethyl anthracene, followed by dropwise addition of a solution of trialkylamine; the reaction mixture is refluxed at 70°C for a certain period of time until the consumption of 10-chloromethyl anthracene is monitored by TLC; chloroform is added to the reaction system until it is clear; after cooling to room temperature, it is left overnight, and the precipitated yellow crystal product is filtered, with a yield of usually 80%-90%.

[0063] In addition, by anion exchange with the corresponding acid of the corresponding counterion, quaternary ammonium salts with different counterions can be obtained.

[0064] Additive E

[0065] In various embodiments of the present application, the photosensitive resin composition can further comprise one or more additives selected from dyes, photo-developers, plasticizers, adhesion promoters, polymerization inhibitors, defoamers, and coating aids, as needed.

[0066] Preferably, the total amount of the additives is 0.5-5.0 parts by mass.

[0067] (II) Photosensitive dry film

[0068] The second aspect of the present application provides a photosensitive dry film, which comprises, from bottom to top, a support layer, a photosensitive resist layer attached to the surface of the support layer, and a protective layer attached to the surface of the photosensitive resist layer, wherein the photosensitive resist layer is formed from the photosensitive resin composition provided in the first aspect of the present application.

[0069] In some preferred embodiments of the present application, the photosensitive dry film comprises, from bottom to top, a PET support layer, a photosensitive resist layer formed by coating and drying the photosensitive resin composition provided in the first aspect of the present application on the surface of the PET support layer, and a PE protective layer.

[0070] (III) Application of photosensitive dry film

[0071] The third aspect of the present application provides the application of the above-mentioned photosensitive dry film in printed circuit boards, lead frames, semiconductor packaging substrates, solar cells, and light-cured inks.

[0072] The present application has the following advantages:

[0073] The anthracene methylene quaternary ammonium salt of the formula (I) and / or the formula (II) structure with the introduction of quaternary ammonium substituted methylene at the 10th and / or 9th position is used as a photosensitizer, which has significant advantages compared with the existing DBA type photosensitizer:

[0074] (1) By introducing quaternary ammonium substituted methylene, the maximum absorption wavelength is red-shifted while maintaining the electron cloud density of the condensed ring aromatic hydrocarbon, which is especially suitable for 405nm light system, significantly improves the initiation efficiency and reduces the exposure energy, improves the photosensitivity, and more efficiently utilizes the exposure light source energy, thereby shortening the exposure time and improving the production efficiency;

[0075] (2) At the same time, the problem of alkoxy carbon-oxygen bond rupture caused by p-π conjugation of DBA is avoided, small molecule fragments are effectively inhibited, defects are reduced and yield is improved, the high-resolution level of DBA is maintained or exceeded, the manufacturing demand of high-fineness line is met, the pattern is more clear and sharp, and it is suitable for the production of miniaturization and high-density electronic devices. By optimizing the photosensitive performance, the defects caused by insufficient or excessive exposure are effectively reduced, the waste rate is reduced, and the production yield is significantly improved;

[0076] (3) Compared with the conventional photosensitizer DBA, DPHA and DAcOA in the prior art, the photosensitizer of the present application not only has more excellent solubility in various commonly used organic solvents, but also has very good solubility in water, which brings great potential for the formula design of the photosensitive curing composition.

[0077] In addition to the above purposes, features and advantages, the present application also has other potential technical advantages, which provides a more optimal solution for the development of related fields.

[0078] In summary, the photosensitive dry film provided by the present application has excellent resolution and adhesion, and has higher photosensitivity than the photosensitive resin composition added with 9,10-dibutoxy anthracene photosensitizer, which is beneficial to improve the production efficiency of the client, meet the demand of high-density and high-fineness of printed circuit board, and the excellent solubility in conventional organic solvents and excellent water solubility are extremely beneficial for the formula development of photosensitive composition. BRIEF DESCRIPTION OF DRAWINGS

[0079] Hereinafter, the embodiments of the present application will be described in detail with reference to the accompanying drawings, in which:

[0080] Figure 1is the ultraviolet absorption spectrum of the photosensitizer TM1 prepared in Example 1 and the photosensitizer TM2 prepared in Example 2 of the present application. 1 H NMR spectrum;

[0081] Figure 2 is the ultraviolet absorption spectrum of the photosensitizer TM1 prepared in Example 1 and the photosensitizer TM2 prepared in Example 2 of the present application. 13 C NMR spectrum;

[0082] Figure 3 is the ultraviolet absorption spectrum of the photosensitizer TM1 prepared in Example 1 and the photosensitizer TM2 prepared in Example 2 of the present application. 1 H NMR spectrum;

[0083] Figure 4 is the ultraviolet absorption spectrum of the photosensitizer TM1 prepared in Example 1 and the photosensitizer TM2 prepared in Example 2 of the present application. 13 C NMR spectrum;

[0084] Figure 5 is the ultraviolet absorption spectrum of the photosensitizer TM1 prepared in Example 1 and the photosensitizer TM2 prepared in Example 2 of the present application.

[0085] Figure 6 is the photobleaching curve of the photosensitizer TM1 prepared in Example 1 of the present application under 405 nm light irradiation.

[0086] Figure 7 is the photobleaching curve of the photosensitizer TM2 prepared in Example 2 of the present application under 405 nm light irradiation. DETAILED DESCRIPTION

[0087] The present application will be further described in conjunction with the specific embodiments given below, which are only intended to illustrate the present application, but not to limit the scope of the present application.

[0088] Example 1

[0089] Preparation of anthracene-10-methylene monotrimethylammonium chloride (photosensitizer TM1)

[0090]

[0091] Under a nitrogen atmosphere, a round bottom flask equipped with a magnetic stirrer was charged with 10-chloromethylanthracene (5 mmol) dissolved in dry methanol 5 mL, followed by the dropwise addition of a trimethylamine solution with a concentration of 30% (15 mmol), the reaction was carried out under reflux at 70°C for about 12 hours until the consumption of 10-chloromethylanthracene was monitored by TLC; chloroform was added to the reaction system until it was clear, cooled to room temperature and left to stand for 12 h, the precipitated yellow crystalline product was filtered (yield 85%).

[0092] The structural formula of the product anthracene-10-methylene monotrimethylammonium chloride (photosensitizer TM1) is as follows:

[0093] The structural formula of the product anthracene-10-methylene monotrimethylammonium chloride (photosensitizer TM1) is as follows: .

[0094] Figure 1 is photosensitizer TM1 1 H NMR spectrum, Figure 2 is photosensitizer TM1 13 C NMR spectrum.

[0095] 1 H NMR (400 MHz, CD3OD): δ 8.51 (s, 1H), 8.39 (d, J = 9.02 Hz, 2H),7.95 (d, J = 8.65 Hz, 2H), 7.58 (t, J = 7.97 Hz, 2H), 7.42 (t, J = 8.04 Hz,2H), 5.53 (s, 2H), 3.00 (s, 9H).

[0096] 13 C NMR (100 MHz, CD3OD): δ 134.2, 133.4, 132.7, 130.9, 129.2, 126.5,125.1, 119.6, 61.1, 54.3.

[0097] Example 2

[0098] Preparation of anthracene-9,10-dimethylene hexamethyl dication dichloride (photosensitizer TM2)

[0099]

[0100] To a round bottom flask equipped with magnetic stirring, 9,10-dichloromethylanthracene (5 mmol) was dissolved in dry methanol 5 mL, followed by dropwise addition of trimethylamine solution 30% (15 mmol). The reaction was carried out at reflux at 70°C for about 12 hours until TLC monitoring of the consumption of 9,10-dichloromethylanthracene; to the reaction system was added chloroform until clarification, cooled to room temperature and left to stand for 12 h, filtering the precipitated yellow crystalline product (yield 82%).

[0101] The product anthracene-9,10-dimethylene hexamethyl dication dichloride (photosensitizer TM2) has the following structural formula:

[0102] .

[0103] Figure 3 is photosensitizer TM2 1 H NMR spectrum, Figure 4 is photosensitizer TM2 13 C NMR spectrum.

[0104] 1 H NMR (400 MHz, CD3OD): δ 7.04 (d, J = 10.28 Hz, 4H), 6.23 (d, J =10.12 Hz, 4H), 4.05 (s, 4H), 1.58 (s, 18H).

[0105] 13 C NMR (100 MHz, CD3OD): δ 133.6, 129.0, 126.5, 124.9, 60.2, 54.5.

[0106] UV-Vis absorption spectrum measurement and photobleaching experiment

[0107] UV-Vis absorption spectrum was tested on Shimadzu UV-1900 UV-Vis spectrophotometer, DBA was dissolved in toluene with a concentration of 4 x 10 -5 mol / L, and TM1-TM2 was dissolved in methanol with a concentration of 4 x 10 -5 mol / L.

[0108] According to Lambert-Beer law, the molar extinction coefficient ε = A bn / c, where A bn is the absorbance of UV-Vis absorption spectrum, and c is the concentration.

[0109] Photobleaching experiment: UV-Vis absorption spectrum of sample solution was tested on Shimadzu UV-1900 UV-Vis spectrophotometer under 450 nm LED light with methanol as solvent.

[0110] Figure 5 are the UV absorption spectrum of photosensitizer TM1 and photosensitizer TM2, respectively; Figure 6 and Figure 7 are the UV absorption spectrum of TM1 and TM2 after different light irradiation time under 405 nm light, respectively. The molar extinction coefficient of photosensitizer TM1, TM2 and DBA is shown in Table 1.

[0111]

[0112] As can be seen from Table 1, the molar extinction coefficient of the photosensitizer of the present application is higher than that of DBA in the similar waveband, which proves that the light-radical conversion ability of the photosensitizer is superior to that of DBA; at the same time, through the comparison of the UV absorption spectrum of Figures 5-7 , it can be seen that the photosensitizer TM1 and TM2 of the present application have very good photobleaching performance and can be completely photobleached in about 60 min.

[0113] Solubility test

[0114] A mixture of 5 g of methoxypolyethylene glycol (350) monoacrylate, 20 g of 10 (ethoxyl) bisphenol A dimethacrylate, 5 g of 6 (propoxyl) bisphenol A dimethacrylate, 10 g of 3 (ethoxyl) trimethylolpropane triacrylate, 4 g of di (trimethylolpropane) tetraacrylate, with acetone, toluene, methanol and water as solvents, was used as a representative of monomers (denoted as "monomer" in the table), to test the solubility of the photosensitizers TM1-TM2 of Examples 1-2 and DBA, DPHA and DAcOA in various solvents and their compatibility with monomers, the solute was added to the solvent in a ratio of 0.1 g solute / 1 g solvent (10% w / w), and the solubility was recorded according to the following grading standard, and the test results are shown in Table 2:

[0115] Good (fast dissolution): under room temperature and stirring conditions, within 1 minute, a clear transparent and uniform solution can be formed;

[0116] Medium (slow dissolution): under room temperature and stirring conditions, more than 5 minutes, a clear transparent and uniform solution can be formed; or under room temperature conditions, it cannot be completely dissolved, but when heated to 50-60°C, a clear transparent and uniform solution can be formed, and there is no obvious phenomenon of turbidity after returning to room temperature;

[0117] Poor (partial dissolution): under room temperature and stirring conditions, more than 5 minutes, it cannot be completely dissolved; or when heated to 50-60°C, it can be completely dissolved, but it becomes obviously turbid after returning to room temperature.

[0118]

[0119] As can be seen from the data in Table 2, compared with the conventional photosensitizers DBA, DPHA and DAcOA in the prior art, the photosensitizers TM1 and TM2 of the present application exhibit more excellent solubility in various commonly used organic solvents and good compatibility with monomers, and more uniquely, they also exhibit very excellent solubility in water, which is very helpful for the formulation design of photocuring compositions and can greatly reduce the development waste and improve product yield.

[0120] Examples 3-8 and Comparative Examples 1-7

[0121] Preparation of photosensitive resin composition

[0122] Referring to the formulation shown in Table 3, the components were mixed uniformly to prepare a photosensitive resin composition, and a solvent, acetone, was added to adjust the viscosity to an appropriate value. Among them, blank means not added.

[0123] The photosensitive resin compositions of Examples 3 to 8 of the present application were prepared according to the formulations shown in Table 3, while Comparative Examples 1 to 4 having photosensitizers TM1 and TM2 outside the range of the present application and Comparative Examples 5 to 7 using conventional photosensitizers were prepared for comparison. The photosensitive resin compositions were prepared by uniformly mixing the components corresponding to Examples 3 to 8 and Comparative Examples 1 to 7 in Table 3. To facilitate coating, a solvent, acetone, was added to adjust the viscosity to an appropriate level. The blank indicates no addition.

[0124]

[0125] The components of the codes in Table 3 are described as follows:

[0126] A (alkali-soluble resin): Acrylate copolymer, solution polymerization, polymerized from methacrylic acid / butyl methacrylate / benzyl methacrylate = 25 / 10 / 65 by mass; solvent: acetone, solid content: 46%, weight average molecular weight: 40000, dispersity: 2.1, acid value: 163 mgKOH / g (Hunan Chuyuan New Material Co., Ltd.);

[0127] B (photopolymerizable monomer) consists of the following components (purchased from Shadoma Guangzhou Chemical Co., Ltd.): 5 g of methoxypolyethylene glycol (350) monoacrylate, 20 g of 10 (ethoxyl) bisphenol A dimethacrylate, 5 g of 6 (propoxy) bisphenol A dimethacrylate, 10 g of 3 (ethoxyl) trimethylolpropane triacrylate, 4 g of di (trimethylolpropane) tetraacrylate;

[0128] C (photoinitiator): 2,2'-bis (o-chlorophenyl)-4,4',5,5'-tetraphenyl-2,2'-dimidazole (BCIM) (purchased from Jiuding Chemical Co., Ltd.);

[0129] E (additive) consists of the following components (purchased from Anjieji Chemical Co., Ltd.): 0.5 g of leuco crystal violet, 0.05 g of malachite green, 0.8 g of p-toluenesulfonamide, 0.03 g of 2,6-di-tert-butyl-4-methylphenol;

[0130] The solvent consists of the following components: 8 g of acetone, 10 g of toluene, and 5 g of methanol.

[0131] Preparation of photosensitive dry film

[0132] The photosensitive resin compositions listed in Table 3 were subjected to the preparation of photosensitive dry films, including the following steps: using a coating experiment device (model: AB4220, TQC, Netherlands) to coat the photosensitive composition slurry prepared according to Table 3 on a 15 μm thick polyethylene terephthalate (PET) support film, respectively; baking at 80°C for 10 min to remove the solvent, and the photosensitive layer thickness after baking was controlled at 30 μm, then a polyethylene film (PE) was overlaid for protection, to obtain a photosensitive dry film.

[0133] Preparation of a substrate with a resist pattern

[0134] The photosensitive compositions of Examples 3-8 of the present application and the photosensitive compositions of Comparative Examples 1-7 as shown in Table 3 were used to prepare substrates with a resist pattern, with the following procedures:

[0135] (1) Photosensitive layer forming step: forming a photosensitive layer on a substrate using a photosensitive composition;

[0136] (2) Exposure step: irradiating a part of the above photosensitive layer with active light rays, so that the above area is photocured to form a cured area;

[0137] (3) Developing step: removing the part of the above photosensitive layer other than the cured area from the substrate, to form a resist pattern on the substrate.

[0138] Hereinafter, the operating conditions of each step are described in detail.

[0139] Photosensitive layer forming step: using a copper-clad laminate with a 35 μm thick rolled 1.2 mm thick copper foil, after surface adjustment and preheating to 80°C, the PE protective film of the photosensitive dry film obtained from each example or comparative example was peeled off, and the photosensitive resin composition layer was laminated on the copper-clad laminate using a hot roll laminator (Zhisheng Technology Co., Ltd., CSL-M25E) at a roll temperature of 110°C, air pressure of 0.35 MPa, and lamination speed of 1.5 m / min, to obtain a test substrate.

[0140] Exposure step: using a direct drawing exposure machine (X-Gene Micro, main wavelength 405 nm) for exposure, and using a Stouffer 41 level phase exposure ruler for photosensitivity test, and the exposure number was controlled at 14-18 levels.

[0141] Developing step: After exposure, the PET support film was peeled off, and an alkali developing machine (manufactured by Guangzhou Julong Printing Plate Equipment Co., Ltd., dry film developing machine) was used to spray a 1 wt% Na2CO3 aqueous solution at 30°C for 2 times the minimum developing time to dissolve and remove the unexposed part of the photosensitive resin layer. After development, the substrate was washed with pure water for 1.5 times the developing time, and then dehydrated using an air knife, and then warm air dried to obtain a substrate with an evaluation cured film. The shortest time required for complete dissolution of the photosensitive resin layer in the unexposed part was taken as the minimum developing time.

[0142] Evaluation items

[0143] 1. Sensitivity evaluation

[0144] On the above-mentioned post-laminated test substrate, a Stouffer 41-stage exposure ruler was placed for sensitivity testing. After the exposure process, the test substrate was allowed to stand for 20 min or more, and then the PET film layer was peeled off, and a 1.0 wt% sodium carbonate aqueous solution was sprayed at 30°C to remove the unexposed resist layer, with a developing time of 2.0 times the minimum developing time. After the above operation, a cured film obtained by curing the photosensitive resin composition was formed on the surface of the substrate. The exposure energy (mJ / cm 2 ) at which the number of remaining stages of the stage exposure ruler obtained by the cured film was 16 stages was evaluated, and the smaller the value, the better the sensitivity of the photosensitive resin composition.

[0145] 2. Resolution evaluation

[0146] On the above-mentioned post-laminated test substrate, a photomask data with a line / space width of n:n (unit: μm) was used to expose at an energy that allowed the number of remaining stages of the Stouffer 41-stage exposure ruler after development to reach 16. After the developing process, the resist pattern was observed using an optical microscope, and the value of the smallest line width at which a complete cured resist line was formed was taken as the value of the resolution (μm) to evaluate the resolution. The smaller the value, the better the resolution.

[0147] 3. Dispersion stability evaluation

[0148] The above-mentioned photosensitive dry film was stored in the dark at 25°C for 2 weeks. The surface of the photosensitive layer was observed using a microscope, and graded as follows:

[0149] ■ represents that the surface of the photosensitive layer is uniform;

[0150] X represents that the surface of the photosensitive layer precipitates undissolved substances.

[0151] 4. Migration evaluation

[0152] After the above prepared 3-layer structure of photosensitive dry film is prepared, the ultraviolet absorption spectrum of the dry film is detected by a UV spectrophotometer to obtain the absorbance A1 of the maximum absorption peak in 350-450 nm; then the dry film is placed at 30°C for 72 hours, the PE film layer on the surface of the photosensitive dry film is removed, and the ultraviolet absorption spectrum of the PET layer and the photosensitive resist layer is detected by a UV spectrophotometer to obtain the absorbance A2 of the maximum absorption peak in 350-450 nm. If the sensitizer migrates to the surface of the PE layer, the absorbance of the maximum absorption peak of the PET layer and the photosensitive resist layer in the wavelength range of 350-450 nm will decrease, that is, the absorbance of the sensitizer migrated to the PE layer is (A1-A2). The migration degree of the photosensitizer, that is, the migration rate A = (A1-A2) / A1, is calculated, and the larger the value is, the greater the migration amount is.

[0153] The judgment basis is as follows:

[0154] O: migration rate A < 0.01;

[0155] X: migration rate A > 0.01.

[0156] 5. Evaluation of development sediment

[0157] The photosensitive resin layer after drying is peeled off, and 18 g of the photosensitive layer resist is dissolved in 1 L of 1% Na2CO3 developing solution. After the photosensitive layer is completely dissolved, the solution is poured into a micro-developing machine, and after 60 minutes of spraying circulation at 30°C and 0.12 MPa pressure, the circulation is stopped. The circulating developing solution is taken out and left to stand for 72 hours, and then the sediment is filtered out with ADVANTEC NO. 2 qualitative filter paper and dried to weigh, and the weight of the sediment on the filter paper is measured as a percentage of the initial 18 g of photosensitive layer w. Specifically, O represents 0≤w≤0.6%, Δ represents 0.6% < w≤0.8%, and X represents 0.8% < w;

[0158] The test results of evaluation items 1-5 are summarized in Table 4 below.

[0159]

[0160] The results in Table 4 show that within the addition range of 0.1-1.0 parts by mass, the photosensitive resin composition (Examples 3-8) of the present application is comparable to or even superior to the conventional photosensitizer DBA, etc. (Comparative Examples 5-7) in photosensitivity and resolution. More importantly, the present application exhibits significant advantages over conventional photosensitizers in dispersion stability, inhibition of photosensitizer migration, and reduction of development sediment. The results of Comparative Examples 1-4 show that when the addition amount of the photosensitizer exceeds the range of the present application, the performance of each item is significantly degraded. The above results fully demonstrate the excellent performance and wide formulation applicability of the photosensitizers TM1 / TM2 of the present application.

[0161] The above results show that the photosensitizer of the present application has wide applicability, and has high photosensitivity and good formulation compatibility, can greatly reduce the developing waste, and has excellent formulation adaptability.

[0162] The above is only a preferred embodiment of the present application, not for limiting the present application. Those skilled in the art can make various modifications and changes within the spirit and principles of the present application, and any modification, equivalent replacement or improvement within the scope should be considered as covered by the protection scope of the present application.

Claims

1. A photosensitive resin composition, based on 100 parts by weight of the photosensitive resin composition, comprising the following components: Alkali-soluble resin A: 50-65 parts; Photopolymerizable monomer B: 35-50 parts, selected from monomers containing olefinic unsaturated double bonds; Photoinitiator C: 2-5 parts, selected from diimidazole compounds; and Photosensitizer D: 0.1-1 part, in, The photosensitizer is an anthracene-10-methylene monoquaternary ammonium salt having the structure shown in formula (I) and / or anthracene-9,10-dimethylene diquaternary ammonium salt having the structure shown in formula (II): Equation (I) Equation (II) Wherein, R in equation (I) a R b R c and R in equation (II) d R e R f R g R h and R i Each is independently selected from hydrogen and C1-C12 alkyl groups; In formulas (I) and (II), R1, R2, R3, R4, R5, R6, R7 and R8 are each independently selected from hydrogen, halogen, C1-C12 alkyl, C1-C12 alkoxy, C6-C12 aryl, C6-C12 aryl substituted with one or more halogens, C6-C12 aryl substituted with one or more C1-C12 alkyls, C6-C12 aryl substituted with one or more C1-C12 alkoxys, C6-C12 aryloxy, C6-C12 aryloxy substituted with one or more halogens, C6-C12 aryloxy substituted with one or more C1-C12 alkyls, and C6-C12 aryloxy substituted with one or more C1-C12 alkoxys. In formula (I), R9 is selected from hydrogen, C1-C12 alkyl, C1-C12 alkoxy, C6-C12 aryl, C6-C12 aryl substituted with one or more C1-C12 alkyl, C6-C12 aryl substituted with one or more C1-C12 alkoxy, C6-C12 aryloxy, C6-C12 aryloxy substituted with one or more C1-C12 alkyl, and C6-C12 aryloxy substituted with one or more C1-C12 alkoxy. In formulas (I) and (II), X is selected from one of halogen, nitrate, acetate, sulfate, trifluoromethanesulfonate, fluoroborate and fluoroantimonate. Optionally, in equation (I) R in part a R b and R c Any two elements in the sequence form a 3-8 element ring with N in the sequence; Optionally, in equation (II) R in part d R e and R f Any two elements in the sequence form a 3-8 element ring with N; and Optionally, in equation (II) R in part g R h and R i Any two elements in the set form a 3-8 elemental ring with N in the set.

2. The photosensitive resin composition according to claim 1, wherein: In formulas (I) and (II), X is selected from one of halogens and nitrates; and In formulas (I) and (II), R1, R2, R3, R4, R5, R6, R7, and R8 are each independently selected from hydrogen, halogens, and C1-C12 alkyl groups; and In formula (I), R9 is selected from hydrogen and C1-C12 alkyl groups.

3. The photosensitive resin composition according to claim 1, wherein, The compound of formula (I) has the following structure: ； Compound (II) has the following structure: 。 4. The photosensitive resin composition according to claim 1, wherein, The content of photosensitizer D is 0.1-0.8 parts by mass.

5. The photosensitive resin composition according to claim 1, wherein, The alkali-soluble resin A is an acrylate copolymer containing aromatic groups; based on the total mass of comonomers during the copolymerization process, the copolymerization ratio of comonomers with aromatic groups is 50-70%; the weight-average molecular weight of the alkali-soluble resin is 20,000-60,000, the resin acid value is 160-220 mg KOH / g, and the molecular weight distribution index is 1.0-3.

0. The photopolymerizable monomer B is selected from one or more of the following: methoxy polyethylene glycol monoacrylate, ethoxy(propoxy)nonylphenol acrylate, ethoxy(propoxy)bisphenol A di(meth)acrylate, ethoxy(propoxy)di(meth)acrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, ethoxy(propoxy)trimethylolpropane tri(meth)acrylate, di(trimethylolpropane)tetraacrylate, ethoxy(propoxy)pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate.

6. The photosensitive resin composition according to claim 1, wherein, The diimidazole compound used as photoinitiator C is selected from 2,4,5-triarylimidazolium dimers.

7. The photosensitive resin composition according to claim 1, wherein, The bisimidazole compound is selected from one or more of 2-(2-chlorophenyl)-4,5-diphenylimidazolium dimer, 2-(2-chlorophenyl)-4,5-di(methoxyphenyl)imidazolium dimer, 2-(2-fluorophenyl)-4,5-diphenylimidazolium dimer, 2-(2-methoxyphenyl)-4,5-diphenylimidazolium dimer, 2-(4-methoxyphenyl)-4,5-diphenylimidazolium dimer, and 2,2',4-tris(2-chlorophenyl)-5-(3,4-dimethoxyphenyl)-4',5'-diphenyl-1,1'-diimidazole.

8. The photosensitive resin composition according to claim 1, wherein, The photosensitive resin composition further comprises one or more additives E selected from dyes, photodevelopers, plasticizers, adhesion promoters, polymerization inhibitors, defoamers, and coating aids; the total amount of additives E is 0.5-5.0 parts by weight.

9. A photosensitive dry film, said photosensitive dry film comprising, from bottom to top: Support layer; A photosensitive resist layer attached to the surface of the support layer; and A protective layer adhering to the surface of the photoresist layer. The photosensitive resist layer is formed using the photosensitive resin composition according to any one of claims 1 to 8.

10. The application of the photosensitive dry film of claim 9 in printed circuit boards, lead frames, semiconductor packaging substrates, solar cells, and photocurable inks.

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