A photosensitive resin composition and its application

Abstract

The present invention discloses a photosensitive resin composition and its application. The photosensitive resin composition comprises 100 parts by mass of an alkali-soluble polyfunctional photosensitive epoxy resin, wherein the polyfunctional group contains three or more epoxy groups; 20 to 60 parts by mass of an alkali-soluble fluorinated polyimide resin; 1 to 40 parts by mass of a photoinitiator; 5 to 50 parts by mass of a photopolymerizable monomer; 10 to 80 parts by mass of a thermosetting component; and 10 to 100 parts by mass of an inorganic filler. Among them, the fluorine-containing substituent in the alkali-soluble fluorinated polyimide resin is selected from -F, -C n F 2n+1 , -OC m F 2m+1 , -C p F 2p -, n = 1 to 6, m = 1 to 2, p = 2 to 10. The photosensitive resin composition has good thermal stability, mechanical properties, exposure sensitivity, good dimensional stability with temperature change, and excellent dielectric properties, and is suitable for high-frequency communication fields.

Description

Technical Field

[0001] The present invention relates to the technical field of photosensitive solder resist inks, and particularly to a photosensitive resin composition and its application. Background Art

[0002] A printed circuit board (PCB) is a substrate for mounting and connecting components in modern electrical appliances and is an important basic assembly in the electronics industry. Among them, photosensitive solder resist ink is one of the key materials for printed circuit boards. It is a protective coating covering the copper wires of printed circuits, used to prevent circuit corrosion and wire breakage, prevent short circuits between lines caused by excessive solder joints, adjust the solder adhesion amount, reduce the dissolution and pollution of copper in the weld seam, save solder, reduce the weight of the instrument, increase the high density of wiring, avoid false soldering, and improve the inspection speed.

[0003] Currently, the photosensitive solder resist inks that are widely used include a photoinitiator and a photosensitive resin composition containing carboxyl groups. Among them, the photosensitive resin is generally an acrylic-modified epoxy resin. Although it has good photocurability, developability, and mechanical properties, the heat resistance of the cured film is insufficient after curing, and it is prone to blistering or oil dropping during soldering, unable to meet the requirements of strict electrical circuit boards. There are mainly two ways to improve heat resistance: physical modification and chemical modification. Physical modification mainly involves adding organic / inorganic fillers. However, the physical blending method is likely to affect the basic properties of the resin-filler composite through the interfacial effect, and phenomena such as uneven dispersion in the system, phase separation during long-term storage, and difficulty in forming a uniform film during coating may occur. Chemical modification mainly involves selecting epoxy resins with higher functionality to make the cured product have a greater degree of crosslinking and thus better heat resistance. It is mainly achieved by introducing some rigid heat-resistant chain segments into the main chain structure of carboxylated epoxy acrylate. However, it is difficult to significantly increase the glass transition temperature only through side chain modification.

[0004] With the advent of high-frequency communication, PCB substrates are gradually developing towards high density and refinement, and the performance requirements for the solder resist coating are also getting higher and higher. Generally, high-precision PCB substrates suitable for high-frequency communication need to undergo a lead-tin soldering process above 260°C during processing. Correspondingly, the photosensitive solder resist ink needs to have higher heat-resistant soldering treatment performance. In addition, to achieve high-speed information processing speed in high-frequency communication, a substrate with a low dielectric constant is required. Therefore, the photosensitive solder resist ink not only needs to have high electrical insulation performance but also needs to have a high glass transition temperature and a low dielectric constant at the same time. However, traditional photosensitive solder resist inks are not suitable for making high-precision circuit boards due to poor heat resistance and high dielectric constant, which limits their application in high-frequency communication.

[0005] In the prior art, in order to reduce the dielectric constant of photosensitive solder resist ink, fillers are mainly added to the photocurable solder resist ink. For example, Chinese Invention Patent CN202010017355.7 discloses a POSS-modified photosensitive solder resist ink with a low dielectric constant and its preparation method. By introducing the dielectric confinement effect generated by modified polyhedral oligomeric silsesquioxane (POSS), that is, a strong self-polarization induction effect is generated at the interface of the contacting heterogeneous media, resulting in the restriction of the electron cloud polarization of the polymer, thereby reducing the dielectric constant of the polymer material. It should be noted that the above technical solution improves the disadvantage of poor compatibility between the low dielectric constant filler and other components to a certain extent, but still cannot completely solve the interfacial effect between the filler and the resin. At the same time, it will affect the addition of other fillers during the production process of subsequent ink products, and the limitation of the resin matrix is also not conducive to the specific implementation of this solution. In addition, introducing a high addition amount of low dielectric constant fillers into the photosensitive solder resist ink will also lead to complex components of the solder resist ink, affecting its elongation at break, lithography performance, etc.

[0006] In summary, the photosensitive solder resist ink in the prior art cannot have good heat resistance, low dielectric constant and dielectric loss performance at the same time, and cannot meet the application requirements in high-frequency communication. Summary of the Invention

[0007] In order to solve the above technical problems, the present invention provides a photosensitive resin composition and its application. The photosensitive resin composition has good thermal stability and mechanical properties, and has excellent film-forming properties. The dry film prepared therefrom has excellent flexibility and a low dielectric constant.

[0008] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0009] On the one hand, the present invention provides a photosensitive resin composition, including:

[0010] (A) Component: 100 parts by mass of an alkali-soluble polyfunctional photosensitive epoxy resin; the polyfunctional group contains three or more epoxy groups;

[0011] (B) Component: 20 - 60 parts by mass of an alkali-soluble fluorinated polyimide resin;

[0012] (C) Component: 1 - 40 parts by mass of a photoinitiator;

[0013] (D) Component: 5 - 50 parts by mass of a photopolymerizable monomer;

[0014] (E) Component: 10 - 80 parts by mass of a thermosetting component;

[0015] (F) Component: 10 - 100 parts by mass of an inorganic filler;

[0016] Among them, the fluorine-containing substituents in the alkali-soluble fluorine-containing polyimide resin are selected from -F, -C n F 2n+1 , -OC m F 2m+1 , -C p F 2p -, n = 1 to 6, m = 1 to 2, p = 2 to 10.

[0017] As a preferred embodiment, the alkali-soluble fluorine-containing polyimide resin is a product obtained by further imidizing the polymerization of a dianhydride monomer, a diamine monomer, and an acid anhydride donor of an alkali-soluble group; the acid anhydride donor of the alkali-soluble group is selected from at least one of a monoanhydride containing a carboxyl group, a dianhydride containing a carboxyl group, and a trianhydride; the fluorine-containing substituents in the alkali-soluble fluorine-containing polyimide resin are provided by any one or several of a dianhydride monomer containing a fluorine-containing substituent, a diamine monomer containing a fluorine-containing substituent, and an acid anhydride donor of an alkali-soluble group containing a fluorine-containing substituent.

[0018] As a preferred embodiment, the dianhydride monomer containing a fluorine-containing substituent is selected from any one or several of the following anhydride compounds:

[0019]

[0020]

[0021] In the technical solution of the present invention, the dianhydride monomer may further include other fluorine-free dianhydrides, and the types are not particularly limited. Specifically, 4,4'-oxybisphthalic anhydride, pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 3,3,4,4-diphenylsulfone tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, bisphenol A type diether dianhydride, and p-phenylene-bis(trimellitate) dianhydride and other dianhydrides can be mentioned. The above dianhydrides can be used alone or in any mixture.

[0022] As a preferred embodiment, the diamine monomer containing a fluorine-containing substituent is selected from any one or several of the following amine compounds:

[0023]

[0024]

[0025]

[0026] In the technical solution of the present invention, the diamine monomer may further include other fluorine-free diamines, and the types are not particularly limited. Specifically, p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, 4,4-bis(4-aminophenoxy)biphenyl, 4,4-bis(3-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)phenyl]ether, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 9,10-bis(4-aminophenyl)anthracene, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 1,4-bis(3-aminopropyldimethylsilyl)benzene, 3,3'-dimethyl-4,4'-diaminodiphenyl sulfone, 9,9-bis(4-aminophenyl)fluorene, etc. can be used alone or in any combination.

[0027] As a preferred embodiment, the alkali-soluble group donor anhydride is selected from any one or more of the following anhydride compounds:

[0028]

[0029] In the technical solution of the present invention, the imidization is carried out under the action of a dehydrating agent;

[0030] Preferably, the dehydrating agent is selected from at least one of an acid anhydride-tertiary amine dehydrating agent, a thionyl chloride-tertiary amine dehydrating agent, and an acetyl chloride-tertiary amine dehydrating agent; the acid anhydride is selected from at least one of acetic anhydride, phthalic anhydride, and trifluoroacetic anhydride; the tertiary amine is selected from at least one of pyridine and triethylamine;

[0031] In certain specific embodiments, the polymerization and imidization are carried out in a solvent. The solvent is not particularly limited and is preferably a good solvent for the reaction raw materials. Specifically, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), N-methylpyrrolidone (NMP), toluene, xylene, methanol, ethanol, acetone, tetrahydrofuran, dimethyl sulfoxide, etc. can be listed. The above can be used alone or in any mixture.

[0032] Preferably, the reaction temperature for the polymerization is -10°C to 80°C, and the reaction time is 4 to 24 hours.

[0033] In the technical solution of the present invention, the molar ratio of the diamine monomer to the dianhydride monomer is not particularly limited and is generally set to 0.9 to 1.1:1.

[0034] Preferably, the reaction temperature for the imidization is 20°C to 120°C, and the reaction time is 1 to 24 hours;

[0035] Preferably, the molecular weight of the alkali-soluble polyimide resin is 3000 to 150000.

[0036] As a preferred embodiment, the acid value of the alkali-soluble polyfunctional photosensitive epoxy resin is 40 to 200 mgKOH / g, and more preferably 50 to 180 mgKOH / g.

[0037] In the technical solution of the present invention, when the acid value of the alkali-soluble polyfunctional photosensitive epoxy resin is less than 40 mgKOH / g, the alkali solubility of the photosensitive resin composition is poor, and the cured film prepared therefrom is difficult to develop in a dilute alkali aqueous solution. When the acid value of the alkali-soluble polyfunctional photosensitive epoxy resin is greater than 200 mgKOH / g, the anti-development performance of the cured film prepared therefrom is poor, and even an effective cured film cannot be formed due to its high solubility in the alkali aqueous solution.

[0038] In the technical solution of the present invention, the acid value represents the number of milligrams of potassium hydroxide (KOH) required to neutralize 1 gram of a chemical substance in a reaction.

[0039] In the technical solution of the present invention, the alkali-soluble polyfunctional photosensitive epoxy resin is a polyfunctional epoxy resin containing a photosensitive group and an alkali-soluble group on the molecular chain; the photosensitive group is selected from at least one of a carbonyl group, a carboxyl group, a peroxide group, and a carbon-carbon double bond; the alkali-soluble group is selected from at least one of a carboxyl group, an acid anhydride group, and an ester group;

[0040] Preferably, the alkali-soluble polyfunctional photosensitive epoxy resin is selected from at least one of novolak epoxy resin, bisphenol A novolak type epoxy resin, naphthalene type epoxy resin, o-cresol novolak epoxy resin, alkylphenol novolak type epoxy resin, dicyclopentadiene type epoxy resin, glycidylamine type epoxy resin, trihydroxybenzene methane type epoxy resin, tetraphenylethane type epoxy resin, diglycidyl phthalate resin, and epoxy compounds which are condensates of phenols and aromatic aldehydes having phenolic hydroxyl groups.

[0041] In some specific embodiments, the preparation method of the alkali-soluble polyfunctional photosensitive epoxy resin comprises the following steps:

[0042] Performing an esterification reaction on (a) a polyfunctional epoxy compound and (b) an unsaturated monocarboxylic acid, and then reacting the obtained esterified product with (c) a saturated / unsaturated polybasic anhydride.

[0043] Examples of the above-mentioned (b) unsaturated monocarboxylic acid include acrylic acid, acrylic acid dimer, methacrylic acid, β-styrylacrylic acid, β-furylacrylic acid, crotonic acid, α-cyanocinnamic acid, cinnamic acid, reaction products of saturated / unsaturated dibasic anhydrides and hydroxy group-containing (meth)acrylate esters, and reaction products of saturated / unsaturated dibasic acids and unsaturated monoglycidyl compounds, etc. The above examples can be used alone or in any mixture.

[0044] Examples of the above-mentioned (c) saturated / unsaturated polybasic anhydrides include: dibasic anhydrides such as maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, and methyltetrahydrophthalic anhydride, etc.; polyaromatic carboxylic anhydrides such as trimellitic anhydride, pyromellitic dianhydride, and benzophenone tetracarboxylic dianhydride, etc.; and other anhydride derivatives such as 5-(2,5-dioxotetrahydrofuranyl)-3-methyl-3-cyclohexenyl-1,2-dicarboxylic anhydride. The above examples can be used alone or in any mixture. In view of the characteristics of the resin cured film, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and succinic anhydride are preferred;

[0045] Preferably, the number average molecular weight of the alkali-soluble polyfunctional photosensitive epoxy resin is 2,000 to 100,000, and more preferably 5,000 to 30,000.

[0046] In the technical solution of the present invention, the type of the photoinitiator is not particularly limited, and specifically, oxime ester-based photoinitiators such as OXE-1 and OXE-2 can be listed; acylphosphine oxide-based photoinitiators such as 2,4,6-trimethylbenzoyl diphenylphosphine oxide; acetophenone-based photoinitiators such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone; benzoin and its alkyl ether photoinitiators, such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether; anthraquinone-based photoinitiators, such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone; thioxanthone-based photoinitiators, such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; ketal-based photoinitiators, such as acetophenone dimethyl ketal, benzyl dimethyl ketal; benzophenone-based photoinitiators, such as benzophenone, 4,4'-bis(diethylamino)benzophenone. The above can be used alone or in any mixture, and oxime ester-based photoinitiators are preferred.

[0047] Preferably, based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the photoinitiator is 5 to 25 parts by mass.

[0048] In the technical solution of the present invention, the polymerizable monomer is selected from hydroxy group-containing (meth)acrylate esters such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate; monofunctional (meth)acrylate esters such as (meth)acrylic acid methyl ester, (meth)acrylic acid ethyl ester, (meth)acrylic acid butyl ester, (meth)acrylic acid lauryl ester; at least one of 1,6-hexanediol bis(meth)acrylate, di / triglycerol bis(meth)acrylate, di / triglycol bis(meth)acrylate, ethoxylated bisphenol A bis(meth)acrylate, neopentyl glycol diethoxy / propoxy bis(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and polydipentaerythritol hexa(meth)acrylate.

[0049] Preferably, based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the polymerizable monomer is 10 to 30 parts by mass.

[0050] In the technical solution of the present invention, the thermosetting component is an epoxy resin, selected from at least one of bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, hydrogenated bisphenol A epoxy resin, brominated bisphenol A epoxy resin, dimethylphenol type epoxy resin, biphenol type epoxy resin, alicyclic epoxy resin, soluble fusible phenolic epoxy resin, cresol soluble epoxy resin, triphenol methane type epoxy resin, N-glycidyl type epoxy resin, isocyanuric acid triglycidyl ester, 2,6-dimethylphenol dimer diglycidyl ether, alicyclic epoxy resin, and xylene type epoxy resin.

[0051] Preferably, based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the thermosetting component is 15 to 45 parts by mass.

[0052] In the technical solution of the present invention, the inorganic filler is an inorganic filler with reactive functional groups on the surface after modification and / or an inorganic filler without surface modification treatment; the inorganic filler is selected from at least one of barium sulfate, barium titanate, calcium oxide, talc powder, fumed silica, silicon dioxide, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, titanium oxide, mica powder, and kaolin, preferably at least one of barium sulfate, silicon dioxide, aluminum oxide, aluminum hydroxide, and calcium carbonate; the reactive functional group is a functional group reactive with the alkali-soluble polyfunctional photosensitive epoxy resin, selected from at least one of epoxy group, ethylenically unsaturated bond, amino group, carboxyl group, hydroxyl group, and mercapto group, preferably at least one of epoxy group, ethylenically unsaturated bond, and hydroxyl group, more preferably ethylenically unsaturated bond, especially vinyl group. These reactive functional groups increase the binding force by forming chemical bonds with the alkali-soluble polyfunctional photosensitive epoxy resin.

[0053] In the technical solution of the present invention, in the inorganic filler with reactive functional groups on the surface after modification, the content of the reactive functional group is 0.001 to 0.5% by weight of the inorganic filler, preferably 0.005 to 0.3% by weight.

[0054] In the technical solution of the present invention, the particle size of the inorganic filler is 0.001 to 100 μm, preferably 0.05 to 20 μm, more preferably 0.05 to 3 μm. In particular, when the photosensitive resin composition needs to be further ground, the particle size of the inorganic filler can also be in other ranges, and there is no special limitation on this.

[0055] Preferably, based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the filler is 10 to 80 parts by mass.

[0056] In some specific embodiments, the photosensitive resin composition further comprises a pigment, which is selected from at least one of phthalocyanine green, phthalocyanine blue, titanium dioxide, carbon black, and lithopone, and preferably a pigment free of free halogens.

[0057] In some specific embodiments, the photosensitive resin composition further comprises an additive, which includes at least one of an epoxy resin curing accelerator, a photoinitiator assistant, a thixotropic thickener, a diluent, a polymerization inhibitor, a thickener, an antifoaming agent, a leveling agent, a coupling agent, an antioxidant, and a rust inhibitor.

[0058] In the technical solution of the present invention, the type of the antifoaming agent is not particularly limited, and preferably it is a silicone antifoaming agent, an acrylate antifoaming agent, or any mixture thereof. Specifically, KS-66 of Shin-Etsu Chemical Co., Ltd. of Japan can be cited; Defoaming agents of TEGO Degussa GmbH of Germany: Foamex N, Foamex 815N, Foamex 825, Foamex 840, Foamex 842; Defoaming agents of DeCHEM of King Industries: DEUCHEM 3200, DEUCHEM 3500, DEUCHEM 5300, DEUCHEM 5400, DEUCHEM 5600, DEUCHEM 6500, DEUCHEM 6800; DEUCHEM 6600, etc.; Acrylate defoaming agents of BYK GmbH of Germany: BYK-051, BYK-052, BYK-053, BYK-057, etc. Based on the total mass of the alkali-soluble polyfunctional photosensitive epoxy resin and the alkali-soluble polyimide resin being 100 parts by mass, the content of the antifoaming agent is 0.05 to 20 parts by mass, preferably 0.1 to 3 parts by mass.

[0059] In the technical solution of the present invention, the type of the leveling agent is not particularly limited, and specifically, BYK-354, BYK-306, BYK-399 of BYK Chemie or any mixture thereof can be cited. Based on the total mass of the alkali-soluble polyfunctional photosensitive epoxy resin and the alkali-soluble polyimide resin being 100 parts by mass, the content of the leveling agent is 0.05 to 20 parts by weight, preferably 0.1 to 5 parts by weight.

[0060] In the technical solution of the present invention, the diluent is an organic solvent, which is not particularly limited. Examples include ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monobutyl ether, etc.; esters such as ethyl acetate, butyl acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol monobutyl ether acetate, etc.; ketones such as methyl ethyl ketone, cyclohexanone, isophorone; aromatic solvents such as toluene, xylene, tetramethylbenzene; and petroleum solvents such as naphtha, oxidized naphtha, solvent naphtha, etc. The above examples can be used alone or in any mixture.

[0061] In the technical solution of the present invention, the type of the epoxy resin curing accelerator is not particularly limited. Specifically, examples include imidazole derivatives such as imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole, etc.; amine compounds such as dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N,N-dimethylbenzylamine, melamine cyanurate, methylguanamine, benzoguanamine, melamine, etc.; hydrazine compounds such as adipic dihydrazide, sebacic dihydrazide, etc.; phosphine compounds such as triphenylphosphine, etc.; s-triazine derivatives such as 2,4-diamino-6-methacryloyloxyethyl-s-triazine, 2-vinyl-2,4-diamino-s-triazine, 2-vinyl-4,6-diamino-s-triazine·isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-s-triazine·isocyanuric acid adduct, etc. In addition, examples also include block isocyanate compounds of dimethylamine 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ produced by Shikoku Kasei Kogyo Co., Ltd.; U-CAT3503N, U-CAT3502T produced by SAN-APRO Co., Ltd., and bicyclic amidine compounds and their salts such as DBU, DBN, U-CATSA102, U-CAT5002, etc. Based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the epoxy resin curing accelerator is 0.05 to 40 parts by mass, preferably 0.1 to 10 parts by mass.

[0062] On the other hand, the present invention provides the use of the above photosensitive resin composition in semiconductor packaging, preferably in the preparation of photosensitive solder resist ink, and more preferably in the preparation of photosensitive solder resist ink suitable for high-frequency communication.

[0063] In the technical solution of the present invention, the method for preparing the photosensitive solder resist ink from the above photosensitive resin composition is not particularly limited. Specifically, after mixing the components, three-roll milling is carried out.

[0064] On the other hand, the present invention provides a photosensitive film obtained by curing the above photosensitive resin composition; preferably, the thickness of the photosensitive film is 5-200 μm, more preferably 15-60 μm, and particularly preferably 20-50 μm.

[0065] On the other hand, the present invention provides a circuit board including a photosensitive film formed by curing the above photosensitive resin composition.

[0066] In the technical solution of the present invention, the preparation method of the circuit board includes the following steps:

[0067] The above photosensitive resin composition is coated on a circuit board with a pre-formed circuit by spraying, flow coating, roll coating, wire bar coating, or screen printing, and dried at 50°C to 90°C; selectively exposed; developed in a dilute alkaline aqueous solution, and then cured at 130°C to 180°C.

[0068] The above technical solution has the following advantages or beneficial effects:

[0069] The present invention provides a photosensitive resin composition and its application. By introducing an alkali-soluble fluorinated polyimide resin into the photosensitive resin composition, on the one hand, the thermal stability and glass transition temperature of the photosensitive resin composition are improved; on the other hand, the introduction of fluorine elements with a small polarizability makes the polyimide have a low dielectric constant and loss, which is beneficial to meeting the application requirements of high-frequency communication. The photosensitive resin composition can be applied to the preparation of photosensitive solder resist ink. The dry film obtained after its curing has good flexibility and mechanical strength, and also has excellent thermal stability and a high glass transition temperature. It has good thermal stability, mechanical properties, exposure sensitivity and other characteristics, and good dimensional stability with temperature changes. At the same time, it has excellent dielectric properties, can meet the increasingly demanding performance requirements of printed circuit boards, and is suitable for applications in high-frequency communication and more scenarios. Detailed Embodiments

[0070] The following embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Therefore, the detailed descriptions of the embodiments of the present invention provided below are not intended to limit the scope of the claimed invention, but merely represent selected embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts belong to the protection scope of the present invention.

[0071] In the present invention, unless otherwise specified, all devices and raw materials can be purchased from the market or are commonly used in this industry. The methods in the following embodiments are conventional methods in this field unless otherwise specified.

[0072] Synthesis Example:

[0073] Synthesis Example 1: Alkali-soluble polyfunctional photosensitive epoxy resin A

[0074] Add 210 g of o-cresol novolac epoxy resin (SQPN-704M purchased from Shandong Shengquan New Materials Co., Ltd., epoxy equivalent is 210), 0.5 g of hydroquinone and 200 g of diethylene glycol monoethyl ether acetate to a four-necked round-bottom flask under a nitrogen atmosphere, stir and heat to 105 °C and maintain this temperature for 1 hour to dissolve all substances; after complete dissolution, cool to 90 °C, then dropwise add 72 g of acrylic acid and 1 g of triphenylphosphine, control the temperature at 95 °C during the dropping process, after the dropping is completed, raise the temperature to 105 °C, and react at this temperature for 12 hours; during the reaction process, measure the acid value of the reactants, until the acid value reaches 0.8 mgKOH / g, cool to 60 °C, then add 75 g of tetrahydrophthalic anhydride, and react at 90 °C for 4 - 8 hours. 2 This synthesis example finally obtains a light yellow alkali-soluble polyfunctional photosensitive resin A with a solid content of 64% and a solid acid value of 92.3 mgKOH / g.

[0075] This synthesis example finally obtains a light yellow alkali-soluble polyfunctional photosensitive resin A with a solid content of 64% and a solid acid value of 92.3 mgKOH / g.

[0076] Synthesis Example 2: The preparation process of fluorine-containing alkali-soluble polyimide resin B-1 is as follows:

[0077] Fill a 100 mL three-necked flask equipped with mechanical stirring with a nitrogen atmosphere, then add 2.5 mmol of diamine component 4,4'-diaminodiphenyl ether (ODA), add NMP at room temperature until the diamine powder is completely dissolved, and add the acid anhydrides: 2.5 mmol of hexafluorodiacid anhydride (6FDA) and 2.5 mmol of trimellitic anhydride in two batches; after stirring at room temperature for 12 h, add N-methylpyrrolidone (NMP) for dilution, and add 3.06 g of acetic anhydride and 2.52 g of triethylamine, and continue to react at room temperature for 12 h, controlling the molecular weight to be around 60,000; drop the reaction solution into deionized water, filter and wash with absolute ethanol to obtain the powder of alkali-soluble polyimide resin B-1.

[0078] Synthesis Example 3: Alkaline-soluble polyimide resin B-2

[0079] A 100 mL three-necked flask equipped with mechanical stirring was filled with a nitrogen atmosphere, and then 2.5 mmol of the diamine component 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane (HFBAPP) was added. NMP was added at room temperature until the diamine powder was completely dissolved. The acid anhydrides: 2.5 mmol of hexafluorodiacid anhydride (6FDA) and 2.5 mmol of trimellitic anhydride were added in two batches; after stirring at room temperature for 12 h, NMP was added for dilution, and 3.06 g of acetic anhydride and 2.52 g of triethylamine were added, and the reaction was continued at room temperature for 12 h to control the molecular weight at about 30,000; the reaction solution was dropped into deionized water, filtered and washed with absolute ethanol to obtain alkaline-soluble polyimide resin B-2 powder.

[0080] Synthesis Example 4: Alkaline-soluble polyimide resin B-3

[0081] A 100 mL three-necked flask equipped with mechanical stirring was filled with a nitrogen atmosphere, and then 2.5 mmol of the diamine component 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane (HFBAPP) was added. NMP was added at room temperature until the diamine powder was completely dissolved. The acid anhydrides: 2.5 mmol of hexafluorodiacid anhydride (6FDA) and 2.5 mmol of trimellitic anhydride tris(1,3,5-benzenetricarboxylate) were added in two batches; after stirring at room temperature for 12 h, NMP was added for dilution, and 3.06 g of acetic anhydride and 2.52 g of triethylamine were added, and the reaction was continued at room temperature for 12 h to control the molecular weight at about 25,000; the reaction solution was dropped into deionized water, filtered and washed with absolute ethanol to obtain alkaline-soluble polyimide resin B-4 powder.

[0082] Synthesis Example 5: Alkaline-soluble polyimide resin B-4

[0083] The preparation process of the alkaline-soluble polyimide resin in this synthesis example is the same as that in Synthesis Example 4, except that the diamine was replaced with diaminodiphenyl ether (ODA), and the acid anhydride was replaced with 4,4'-oxybisphthalic anhydride (ODPA) and trimellitic anhydride to obtain alkaline-soluble polyimide resin B-5 powder.

[0084] Example: Photosensitive resin composition

[0085] The photosensitive resin composition was prepared according to the parts by mass shown in Table 1:

[0086] Table 1:

[0087]

[0088]

[0089] Note 1: Photoinitiator: OXE-2 purchased from Tianjin Huiren Hengtong Technology Co., Ltd.;

[0090] Note 2: Epoxy resin: YSLV-80XY purchased from Nippon Steel & Sumitomo Metal Corporation of Japan;

[0091] Note 3: Silicon dioxide, with a particle size of 100 nm to 3 μm;

[0092] Note 4: Barium sulfate: B-34 purchased from Sakai Chemical Industry Co., Ltd. of Japan;

[0093] Note 5: Pigment: Phthalocyanine green purchased from BASF;

[0094] Note 6: Levelling agent: purchased from BYK Chemie GmbH of Germany;

[0095] Note 7: Defoaming agent: KS-66 purchased from Shin-Etsu Chemical Co., Ltd. of Japan;

[0096] Note 8: Diluent: Carbitol acetate.

[0097] Effect Example: Photosensitive solder resist ink

[0098] The photosensitive resin compositions in the examples and comparative examples were mixed by stirring and a three-roll mill to prepare a photosensitive solder resist ink. The photosensitive solder resist ink was coated, maintaining a thickness between 25 microns, soft-baked at 80 °C for 10 minutes, exposed, developed with 1% dilute sodium carbonate solution, thermally cured at 170 °C for 1 hour, and then the relevant properties were tested. The results are shown in Table 2.

[0099] Table 2

[0100]

[0101]

[0102] From the above results, it shows that the alkali-soluble polyimide resin prepared from the fluorinated diamine monomer can reduce the dielectric constant of the photosensitive solder resist ink to below 3.0, and the dielectric loss to about 0.004 (at 1 GHz). At the same time, its glass transition temperature is as high as above 180 °C, and the 5% thermal weight loss is above 350 °C, and the lithography performance is excellent. Among them, when the resolution of the lithography pattern of the line or round hole reaches 40 μm, it is judged as excellent; when 40 μm < resolution < 60 μm, it is judged as good; when 60 μm < resolution < 80 μm, it is judged as passing. Compared with Comparative Example 1, both the thermodynamic and dielectric properties have been greatly improved.

[0103] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A photosensitive resin composition, characterized in that, it comprises: (A) component: 100 parts by mass of an alkali-soluble polyfunctional photosensitive epoxy resin; The polyfunctional group contains three or more epoxy groups; (B) component: 20 to 60 parts by mass of an alkali-soluble fluorinated polyimide resin; (C) component: 1 to 40 parts by mass of a photoinitiator; (D) component: 5 to 50 parts by mass of a photopolymerizable monomer; (E) component: 10 to 80 parts by mass of a thermosetting component; (F) component: 10 to 100 parts by mass of an inorganic filler; Among them, the fluorine-containing substituents in the alkali-soluble fluorine-containing polyimide resin are selected from -F, -C n F 2n+1 , -OC m F 2m+1 , -C p F 2p -, n = 1 to 6, m = 1 to 2, p = 2 to 10; The alkali-soluble fluorinated polyimide resin is a product obtained by polymerizing a dianhydride monomer, a diamine monomer and an alkali-soluble group donor anhydride and then further imidizing; The alkali-soluble group donor anhydride is selected from at least one of a monoanhydride containing a carboxyl group, a dianhydride containing a carboxyl group, and a trianhydride; The fluorine-containing substituents in the alkali-soluble fluorinated polyimide resin are provided by any one or more of a dianhydride monomer containing a fluorine-containing substituent, a diamine monomer containing a fluorine-containing substituent, and an alkali-soluble group donor anhydride containing a fluorine-containing substituent; The acid value of the alkali-soluble polyfunctional photosensitive epoxy resin is 40 to 200 mg KOH / g; The alkali-soluble polyfunctional photosensitive epoxy resin is a polyfunctional epoxy resin containing a photosensitive group and an alkali-soluble group on the molecular chain; The photosensitive group is selected from at least one of a carbonyl group, a carboxyl group, a peroxy group and a carbon-carbon double bond; The alkali-soluble group is selected from at least one of a carboxyl group, an acid anhydride and an ester group; The thermosetting component is an epoxy resin, selected from at least one of bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, dimethylxylenol type epoxy resin, biphenol type epoxy resin, alicyclic epoxy resin, soluble and fusible phenolic epoxy resin, cresol-soluble epoxy resin, triphenol methane type epoxy resin, N-glycidyl type epoxy resin, isocyanuric acid triglycidyl ester, 2,6-dimethylphenol dimer diglycidyl ether, alicyclic epoxy resin, xylene type epoxy resin.

2. The photosensitive resin composition according to claim 1, characterized in that, the dianhydride monomer containing a fluorine-containing substituent is selected from any one or more of the following anhydride compounds:

3. The photosensitive resin composition according to claim 1, characterized in that, the diamine monomer containing a fluorine-containing substituent is selected from any one or more of the following amine compounds:

4. The photosensitive resin composition according to claim 1, characterized in that, the alkali-soluble group donor anhydride is selected from any one or more of the following anhydride compounds:

5. The photosensitive resin composition according to claim 1, characterized in that, the acid value of the alkali-soluble polyfunctional photosensitive epoxy resin is 50 to 180 mg KOH / g.

6. The photosensitive resin composition according to claim 1, characterized in that, The alkali-soluble polyfunctional photosensitive epoxy resin is selected from at least one of novolak epoxy resin, bisphenol A novolak type epoxy resin, naphthalene type epoxy resin, o-cresol novolak epoxy resin, alkylphenol novolak type epoxy resin, dicyclopentadiene type epoxy resin, glycidylamine type epoxy resin, trihydroxybenzene methane type epoxy resin, tetraphenylethane type epoxy resin, diglycidyl phthalate resin, and epoxy compounds of condensates of phenols and aromatic aldehydes having phenolic hydroxyl groups.

7. The photosensitive resin composition according to claim 1, wherein, the number average molecular weight of the alkali-soluble polyfunctional photosensitive epoxy resin is 2,000 to 100,000.

8. The photosensitive resin composition according to claim 7, wherein, the number average molecular weight of the alkali-soluble polyfunctional photosensitive epoxy resin is 5,000 to 30,000.

9. The photosensitive resin composition according to claim 1, wherein, based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the photoinitiator is 5 to 25 parts by mass.

10. The photosensitive resin composition according to claim 1, wherein, based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the polymerizable monomer is 10 to 30 parts by mass.

11. The photosensitive resin composition according to claim 1, wherein, based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the thermosetting component is 15 to 45 parts by mass.

12. The photosensitive resin composition according to claim 1, wherein, the inorganic filler is an inorganic filler having reactive functional groups on the surface after modification and / or an inorganic filler without surface modification treatment; the inorganic filler is selected from at least one of barium sulfate, barium titanate, calcium oxide, talc, fumed silica, silicon dioxide, clay, magnesium carbonate, calcium carbonate, alumina, aluminum hydroxide, titanium oxide, mica powder, and kaolin.

13. The photosensitive resin composition according to claim 12, wherein, the inorganic filler is selected from at least one of barium sulfate, silicon dioxide, alumina, aluminum hydroxide, and calcium carbonate.

14. The photosensitive resin composition according to claim 12, wherein, the reactive functional group is a functional group reactive with the alkali-soluble polyfunctional photosensitive epoxy resin, and is selected from at least one of an epoxy group, an ethylenically unsaturated bond, an amino group, a carboxyl group, a hydroxyl group, and a thiol group.

15. The photosensitive resin composition according to claim 14, wherein, the reactive functional group is at least one of an epoxy group, an ethylenically unsaturated bond, and a hydroxyl group.

16. The photosensitive resin composition according to claim 15, wherein, the reactive functional group is an ethylenically unsaturated bond.

17. The photosensitive resin composition according to claim 16, wherein, the reactive functional group is a vinyl group.

18. The photosensitive resin composition according to claim 1, wherein, Based on 100 parts by mass of an alkali-soluble polyfunctional photosensitive epoxy resin, the content of the inorganic filler is 10 to 80 parts by mass.

19. The photosensitive resin composition according to claim 1, wherein, the photosensitive resin composition further comprises a pigment selected from at least one of phthalocyanine green, phthalocyanine blue, titanium dioxide, carbon black, and lithopone.

20. The photosensitive resin composition according to claim 19, wherein, the pigment is a pigment free of free halogen.

21. The photosensitive resin composition according to claim 1, wherein, the photosensitive resin composition further comprises an additive, and the additive comprises at least one of an epoxy resin curing accelerator, a photoinitiator assistant, a thixotropic thickener, a diluent, a polymerization inhibitor, a tackifier, an antifoaming agent, a leveling agent, a coupling agent, an antioxidant, and a rust inhibitor.

22. The photosensitive resin composition according to claim 21, wherein, based on a total mass of 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin and the alkali-soluble polyimide resin, the content of the antifoaming agent is 0.05 to 20 parts by mass.

23. The photosensitive resin composition according to claim 22, wherein, based on a total mass of 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin and the alkali-soluble polyimide resin, the content of the antifoaming agent is 0.1 to 3 parts by mass.

24. The photosensitive resin composition according to claim 21, wherein, based on a total mass of 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin and the alkali-soluble polyimide resin, the content of the leveling agent is 0.05 to 20 parts by weight.

25. The photosensitive resin composition according to claim 24, wherein, based on a total mass of 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin and the alkali-soluble polyimide resin, the content of the leveling agent is 0.1 to 5 parts by weight.

26. The photosensitive resin composition according to claim 21, wherein, based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the epoxy resin curing accelerator is 0.05 to 40 parts by mass.

27. The photosensitive resin composition according to claim 26, wherein, based on 100 parts by mass of the alkali-soluble polyfunctional photosensitive epoxy resin, the content of the epoxy resin curing accelerator is 0.1 to 10 parts by mass.

28. Use of the photosensitive resin composition according to any one of claims 1 - 27 in semiconductor packaging.

29. The use according to claim 28, wherein, use in preparing a photosensitive solder resist ink.

30. The use according to claim 29, wherein, use in preparing a photosensitive solder resist ink suitable for high-frequency communication.

31. A photosensitive film, wherein, it is cured from the photosensitive resin composition according to any one of claims 1 - 27.

32. The photosensitive film according to claim 31, wherein, the thickness of the photosensitive film is 5 to 200 μm.

33. The photosensitive film according to claim 32, wherein, the thickness of the photosensitive film is 15 to 60 μm.

34. The photosensitive film according to claim 33, wherein, the thickness of the photosensitive film is 20 to 50 μm.

35. A circuit board, wherein, it comprises a photosensitive film formed by curing the photosensitive resin composition according to any one of claims 1-27.

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