Alkaline development type resin composition, photo-curable dry film thereof, cured product thereof, and printed wiring board formed using the same

Abstract

To provide an alkali developable resin composition capable of forming a solder resist layer having excellent adhesive force and thermal shock resistance, a photocurable dry film of the same, a cured product of the same, and a printed wiring board formed by using them.SOLUTION: The alkaline development type resin composition contains (A) a vinyl ester resin, (B) a photopolymerization initiator, (C) glass powder, (D) a compound having two or more ethylenically unsaturated groups in one molecule, and (E) an inorganic filler. The inorganic filler (E) contains talc, the glass powder (C) contains, in% by weight, 60 to 65% SiO2, 0.01 to 0.02% Fe2O3, 14 to 20% Al2O3, 6 to 9% CaO, 1 to 2% MgO, and 8 to 12% B2O3, and the Mohs hardness of the glass powder (C) is less than 6.5.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an alkaline developable resin composition suitable for forming a solder resist layer or the like on a printed wiring board, a photocurable dry film thereof, and a cured product thereof, and in particular to an alkaline developable resin composition capable of forming a solder resist layer having excellent adhesion and thermal shock resistance, a photocurable dry film thereof, a cured product thereof, and a printed wiring board. [Background technology]

[0002] Currently, the formation of solder resist layers (solder resists) on some consumer printed wiring boards and most industrial printed wiring boards uses alkaline development-type solder resist agents that are exposed to ultraviolet light, developed to form a pattern, and then fully cured (mainly cured) by heat and / or light irradiation. Furthermore, for semiconductor devices used in vehicles such as automobiles, trains, ships, and aircraft, there is a trend toward using solder resist agents for highly reliable electronic materials as printed wiring board solder resist agents. However, due to factors such as thermal expansion, typical alkaline development solder resists typically have poor crack resistance during thermal cycles and poor reliability against changes in environmental temperature. Furthermore, the solder resist layer must have excellent adhesion to protect the copper circuitry and maintain aesthetic appearance. While selecting talc as a filler can improve cracking, it also results in poor adhesion. Furthermore, while using talc and silica as fillers may satisfy the thermal shock resistance requirements for automotive solder resists, the adhesion is still insufficient.

[0003] For example, the photocurable solder resist of Patent Document 1 uses silica, barium sulfate, and talc as fillers. Patent Document 2 describes a curable resin composition for a solder resist layer that contains a carboxyl group-containing resin, a thermosetting component, a flame retardant, and an ion scavenger. The ion scavenger is a mixture of a hydrotalcite-based ion scavenger and a non-hydrotalcite-based ion scavenger, and aluminum hydroxide is used as an inorganic filler. Patent Document 3 describes a curable resin composition used as a permanent mask for printed wiring boards, which contains a resin containing an ethylenically unsaturated group and a carboxyl group in its molecule, a photopolymerization initiator, a photopolymerizable monomer, titanium oxide surface-treated with alumina, barium sulfate and / or talc, and an organic solvent. Patent Document 4 describes an ultraviolet light-curable liquid photosensitive solder resist flexible ink that uses barium sulfate, talc, or silica as a filler. [Prior art documents] [Patent documents]

[0004] Patent document 1: CN114716868A Patent document 2: CN108137791A Patent document 3: CN101798432A Patent document 4: CN106380929A Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide an alkaline developable resin composition capable of forming a solder resist layer having excellent adhesion and thermal shock resistance, a photocurable dry film thereof, a cured product thereof, and a printed wiring board. [Means for solving the problem]

[0006] As a result of extensive research into solving the above problems, the present inventors have found that the type of filler is The inventors have found that the Mohs hardness of the (C) glass powder is less than 6.5, and have found that the Mohs hardness of the (C) glass powder is less than 6.5. The inventors have found that the Mohs hardness of the (C) glass powder is less than 6.5, and ...

[0007] That is, the alkaline developable resin composition of the present invention contains (A) a vinyl ester resin, (B) a photopolymerization initiator, (C) glass powder, (D) a compound having two or more ethylenically unsaturated groups in one molecule, and (E) an inorganic filler, wherein the (E) inorganic filler contains talc, the (C) glass powder contains, by weight, 60 to 65% SiO2, 0.01 to 0.02% Fe2O3, 14 to 20% Al2O3, 6 to 9% CaO, 1 to 2% MgO, and 8 to 12% BO3, and the (C) glass powder has a Mohs hardness of less than 6.5.

[0008] It is also preferable to contain (F) other additives other than (B) the photopolymerization initiator and (C) the glass powder.

[0009] It is also preferable to contain (G) an epoxy resin.

[0010] It is also preferred that the solvent contains (H) an organic solvent.

[0011] The photocurable dry film of the present invention is characterized in that it is obtained by applying the alkaline developing resin composition to a carrier film and drying it.

[0012] The cured product of the present invention is characterized in that it is obtained by applying the alkaline developable resin composition to copper and drying the composition to obtain a coating film, or by applying the alkaline developable resin composition to a carrier film and drying the composition, laminating the resulting photocurable dry film on copper, and photocuring the resulting coating film.

[0013] The printed wiring board of the present invention is characterized in that it is obtained by applying the alkaline developable resin composition to a substrate having a copper circuit and drying the composition to obtain a coating film, or by applying the alkaline developable resin composition to a carrier film, drying the composition, laminating the resulting photocurable dry film on a substrate having a copper circuit, photocuring the resulting coating film, and then thermally curing the resulting coating film.

[0014] The alkaline developable resin composition of the present invention contains (A) a vinyl ester resin, (B) a photopolymerization initiator, (C) glass powder, (D) a compound having two or more ethylenically unsaturated groups in one molecule, and (E) an inorganic filler, wherein the (E) inorganic filler contains talc, the (C) glass powder contains, by weight, 60 to 65% SiO2, 0.01 to 0.02% Fe2O3, 14 to 20% Al2O3, 6 to 9% CaO, 1 to 2% MgO, and 8 to 12% BO3, and is most significantly characterized in that the (C) glass powder has a Mohs hardness of less than 6.5.

[0015] Based on the characteristic configuration of the present invention, by using soft composite glass powder and talc in combination and adjusting the compounding ratio of the two, it is possible to improve adhesive strength while maintaining excellent thermal shock resistance.

[0016] In contrast, conventional techniques use talc and barium sulfate in combination as fillers. Although this method satisfies the requirement for thermal shock resistance of the solder resist, it results in poor adhesion (for example, Patent Document 1, etc.).

[0017] As described above, the inventors of the present invention conducted extensive research and found that, as a filler, talc has good flexibility and excellent crack resistance in a temperature cycle test (TCT test), but that adhesive strength deteriorates as the amount used increases. Glass powder, particularly soft composite glass powder, can provide excellent adhesive strength as a filler, but its thermal shock resistance is insufficient. By using talc and glass powder together as fillers, it is possible to simultaneously maintain excellent thermal shock resistance and adhesive strength, thereby achieving the above-mentioned object of the present invention. [Effects of the Invention]

[0018] As described above, the present invention can provide an alkaline developable resin composition capable of forming a solder resist layer having excellent adhesion and thermal shock resistance, a photocurable dry film thereof, a cured product thereof, and a printed wiring board. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a photograph showing that cracks have occurred in a solder resist film for evaluating thermal shock resistance in an example. [Figure 2] FIG. 2 is a photograph showing that no cracks were generated in the solder resist film used to evaluate thermal shock resistance in the example. [Figure 3] 1 is an image of a dolly used to evaluate adhesive strength in the examples. DETAILED DESCRIPTION OF THE INVENTION

[0020] Each of the components of the alkaline developing resin composition of the present invention will be described below.

[0021] The alkaline-developable resin composition of the present invention contains (C) glass powder and (E) inorganic filler, and the (E) inorganic filler contains talc as an essential component. Therefore, the (C) glass powder and (E) inorganic filler will first be described.

[0022] (C) Glass powder The glass powder (C) used in the alkaline developable resin composition of the present invention is a powdered, glassy, ​​amorphous inorganic material containing silica as the main component, and is typically formed by high-temperature sintering of inorganic minerals as the main raw materials.

[0023] The glass powder (C) used in the alkaline-developable resin composition of the present invention is preferably a soft composite glass powder, as this is more advantageous for achieving the objects of the present invention. The glass powder (C) may be either a non-surface-treated glass powder or a surface-treated glass powder.

[0024] The soft composite glass powder typically has a component composition of SiO2: 60-65%, Fe2O3: 0.01-0.02%, Al2O3: 14-20%, CaO: 6-9%, MgO: 1-2%, and B2O3: 8-12%, preferably SiO2: 61-64%, Fe2O3: 0.012-0.019%, Al2O3: 15-19%, CaO: 6.5-8.5%, MgO: 1.1-1.8%, and B2O3: 9-11%, and more preferably SiO2: 62-63%, Fe2O3: 0.014-0.018%, Al2O3: 16-18%, CaO: 7-8%, MgO: 1.2-1.6%, and B2O3: 9.5-10.5%.

[0025] The soft composite glass powder has a Mohs hardness of less than 6.5, preferably in the range of 4.8 to 6.2, and more preferably in the range of 5 to 6.

[0026] The present inventors have discovered that, in order to achieve both excellent thermal shock resistance and adhesive strength in a solder resist layer, by using talc as a filler and incorporating (C) glass powder, adhesive strength can be significantly improved while maintaining excellent thermal shock resistance. In this case, the blending ratio of the two components, i.e., talc:glass powder, is suitably 90:10 to 10:90 by weight, preferably 80:20 to 20:80, more preferably 75:25 to 25:75, and even more preferably 70:30 to 30:70. In this way, an alkaline-developable resin composition can be obtained that can realize a solder resist layer excellent in both thermal shock resistance and adhesive strength.

[0027] The blending ratio of (C) glass powder is suitably 10 to 90 parts by weight, preferably 20 to 80 parts by weight, more preferably 30 to 70 parts by weight, and even more preferably 40 to 60 parts by weight, per 100 parts by weight (solids content) of the (A) vinyl ester resin. If the amount of (C) glass powder used is within the above range, excellent thermal shock resistance can be obtained and improved adhesion can be ensured. If the amount exceeds the above range, the properties as a solder resist agent will be reduced, which is undesirable.

[0028] Commercially available soft composite glass powders include K10 (manufactured by Suzhou Jin Yi New Materials Co., Ltd.) and G2C (manufactured by Shanghai Sibelco Mining Co., Ltd.).

[0029] (E) Inorganic filler In the alkaline-developable resin composition of the present invention, the talc used as the inorganic filler (E) is used to improve thermal shock resistance, and the inorganic filler (E) does not include the glass powder (C), particularly the soft composite glass powder.

[0030] The talc may be any one of magnesium carbonate, serpentine, silica / silica-alumina, and magnesium deposits, i.e., any one of so-called silicate minerals, and may be in the form of a block or a fine powder. Surface treatment may or may not be performed. The average particle size of the talc is suitably 1.0 to 20.0 μm, more preferably 2.0 to 10 μm, and even more preferably 3.0 to 8.0 μm. Examples of commercially available talc include HD25 manufactured by Talc Mining Co., Ltd., Pingdu City, Shandong Province, and LMP-100 manufactured by Fuji Talc Industry Co., Ltd.

[0031] The amount of talc is suitably 10 to 90 parts by weight, preferably 20 to 80 parts by weight, and more preferably 30 to 70 parts by weight, per 100 parts by weight of (A) vinyl ester resin (solid content equivalent).Within the above range, adhesion can be improved while excellent thermal shock resistance is ensured.

[0032] Fillers other than talc and the above-mentioned (C) glass powder, such as silica, may be blended within the scope of the present invention. The silica may be either amorphous or crystalline, or a mixture thereof. Amorphous (fused) silica is particularly preferred. Surface treatment may or may not be performed. The silica typically has a Mohs hardness of 6.5 or higher. The average particle size of the silica is suitably 0.1 to 10.0 μm, more preferably 1.0 to 8.0 μm, and even more preferably 2.0 to 6.0 μm. Commercially available silica products include CS1002 and CS1002A manufactured by Jiangsu NOVORAY New Materials Co., Ltd., A-8 manufactured by Sibelco Co., Ltd., SE-40 manufactured by Tokuyama Co., Ltd., MSV25G manufactured by Tatsumori Co., Ltd., MLV-2114 manufactured by Tatsumori Co., Ltd., SO-E5 manufactured by ADMATECHS, and SO-E2 manufactured by ADMATECHS.

[0033] (A) Vinyl ester resin

[0034] As the (A) vinyl ester resin in the photocurable thermosetting resin composition of the present invention, known resins having an ethylenically unsaturated double bond in the molecule can be used in terms of photocurability and development resistance. Furthermore, in order to impart alkaline developability, carboxyl group-containing resins having an ethylenically unsaturated double bond in the molecule are particularly preferred. Furthermore, the unsaturated double bond is more preferably derived from acrylic acid, methacrylic acid, or a derivative thereof. As the (A) vinyl ester resin, resins using epoxy resins as a starting material, polyurethane resins having a urethane skeleton, copolymer resins having a copolymer structure of unsaturated carboxylic acids, and resins using phenolic compounds as a starting material are preferred. Specific examples of the (A) vinyl ester resin are shown below.

[0035] (1) A vinyl ester resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth)acrylic acid with one or more other compounds having an unsaturated double bond. (2) Photosensitive vinyl ester resins obtained by adding an ethylenically unsaturated group as a side group to a copolymer of an unsaturated carboxylic acid such as (meth)acrylic acid and one or more other compounds having an unsaturated double bond, using a compound having an epoxy group and an unsaturated double bond, such as glycidyl (meth)acrylate or 3,4-epoxycyclohexylmethyl (meth)acrylate, or (meth)acrylic acid chloride, etc. (3) A photosensitive vinyl ester resin obtained by reacting a copolymer of a compound having an epoxy group and an unsaturated double bond, such as glycidyl (meth)acrylate or 3,4-epoxycyclohexylmethyl (meth)acrylate, with another compound having an unsaturated double bond, with an unsaturated carboxylic acid, such as (meth)acrylic acid, and then reacting the resulting secondary hydroxyl group with a polybasic acid anhydride. (4) A photosensitive vinyl ester resin obtained by reacting a copolymer of an acid anhydride having an unsaturated double bond, such as maleic anhydride, and another compound having an unsaturated double bond with a compound having a hydroxyl group and an unsaturated double bond, such as 2-hydroxyethyl (meth)acrylate; (5) A vinyl ester resin obtained by reacting a polyfunctional epoxy compound with an unsaturated monocarboxylic acid and then reacting the resulting hydroxyl group with a saturated or unsaturated polybasic acid anhydride. (6) A vinyl ester resin containing hydroxyl groups and carboxyl groups, which is obtained by reacting a hydroxyl group-containing polymer such as a polyvinyl alcohol derivative with a saturated or unsaturated polybasic acid anhydride, and then reacting the resulting carboxylic acid with a compound having an epoxy group and an unsaturated double bond in one molecule. (7) A vinyl ester resin obtained by reacting a reaction product of a polyfunctional epoxy compound, an unsaturated monocarboxylic acid, and a compound having at least one alcoholic hydroxyl group and one reactive group other than the alcoholic hydroxyl group that reacts with an epoxy group in one molecule with a saturated or unsaturated polybasic acid anhydride. (8) A vinyl ester resin obtained by reacting an unsaturated monocarboxylic acid with a polyfunctional oxetane compound having at least two oxetane rings in one molecule, and then reacting a saturated or unsaturated polybasic acid anhydride with the primary hydroxyl group in the resulting modified oxetane resin; and (9) A vinyl ester resin obtained by reacting a polyfunctional epoxy resin with an unsaturated monocarboxylic acid, followed by reaction with a polybasic acid anhydride to obtain a carboxyl group-containing resin, and then reacting the resulting resin with a compound having one oxirane ring and one or more ethylenically unsaturated groups in the molecule; (10) A vinyl ester resin obtained by reacting an unsaturated monocarboxylic acid with a bifunctional epoxy compound and then reacting the resulting hydroxyl group with a saturated or unsaturated polybasic acid anhydride.

[0036] Among these examples, the vinyl ester resins (2), (5), (7) and (9) are particularly preferred.

[0037] In this specification, (meth)acrylate refers to acrylate, methacrylate, and This is a general term for mixtures of these, and the same applies to other similar expressions below.

[0038] The vinyl ester resin (A) described above has a plurality of free carboxyl groups in the side chains of the main chain polymer, and therefore can be developed using a dilute alkaline aqueous solution.

[0039] The acid value of the vinyl ester resin (A) is preferably in the range of 40 to 200 mgKOH / g, more preferably 45 to 120 mgKOH / g. If the acid value of the vinyl ester resin (A) is less than 40 mgKOH / g, alkaline development becomes difficult. On the other hand, if the acid value exceeds 200 mgKOH / g, the exposed area will be dissolved in the developer to a greater extent, resulting in lines that are thinner than necessary, and in some cases, the exposed and unexposed areas will be dissolved and peeled off indistinguishably in the developer, making it difficult to draw a normal resist pattern.

[0040] The weight-average molecular weight of the vinyl ester resin (A) varies depending on the resin skeleton, but is generally in the range of 2,000 to 150,000, and preferably 5,000 to 100,000. If the weight-average molecular weight is less than 2,000, the tack-free performance after application to a substrate and drying may be poor. Furthermore, the moisture resistance of the coating film after exposure may be poor, leading to film loss during development and significantly reduced resolution. On the other hand, if the weight-average molecular weight exceeds 150,000, the developability may be significantly poor and storage stability may be poor.

[0041] The blending amount of (A) vinyl ester resin is desirably in the range of 20 to 60 mass % of the total composition, calculated as solid content, and preferably 25 to 50 mass %. If the blending amount of (A) vinyl ester resin is less than the above range, the strength of the coating film will decrease, which is not preferable. On the other hand, if the blending amount is more than the above range, the viscosity of the composition will increase or the coatability will decrease, which is not preferable.

[0042] (B) Photopolymerization initiator The photopolymerization initiator used in the alkaline developable resin composition of the present invention is not particularly limited as long as it is a photopolymerization initiator generally used in alkaline developable resin compositions.

[0043] Known photopolymerization initiators can be used, including benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, and benzoin ethyl ether; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, and 4-(1-t-butyldioxy-1-methylethyl)acetophenone; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, and 1-chloroanthraquinone. thioxanthone such as isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, and 2,4-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzil dimethyl ketal; benzophenones such as benzophenone, 4-(1-t-butyldioxy-1-methylethyl)benzophenone and 3,3',4,4'-tetrakis(t-butyldioxycarbonyl)benzophenone; and oxoanthracene.

[0044] Furthermore, as the photopolymerization initiator, an oxime ester-based photopolymerization initiator having an oxime ester group, an alkylphenone-based photopolymerization initiator, an α-aminoacetophenone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, a titanocene-based photopolymerization initiator, a phosphate ester-based photopolymerization initiator, or the like can also be used.

[0045] Commercially available oxime ester photopolymerization initiators include Irgacure OXE01 and Irgacure OXE02 manufactured by BASF Japan, and N-1919 and NCI-831 manufactured by ADEKA CORPORATION. A photopolymerization initiator having an ester group can be suitably used, and specifically, an oxime ester compound having a carbazole structure can be mentioned.

[0046] Commercially available alkylphenone photopolymerization initiators include α-hydroxyalkylphenones such as Omnirad 184, Omnirad 1173, Omnirad 2959, and Omnirad 127 manufactured by IGM Resins BV.

[0047] Specific examples of the α-aminoacetophenone photopolymerization initiator include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, and N,N-dimethylaminoacetophenone. Commercially available products that can be used include Omnirad 907, Omnirad 369, and Omnirad 379 manufactured by IGM Resins BV.

[0048] Specific examples of the acylphosphine oxide photopolymerization initiator include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, trifunctional or higher acylphosphine photopolymerization initiators, etc. The trifunctional or higher acylphosphine photopolymerization initiator may be a photopolymerization initiator having three or more acylphosphine oxide skeletons in one molecule, and can be represented by the following formula (I): JPEG2026016443000001.jpg27169In formula, A's are independently a single bond, O, S or NR 3 represents G is a multifunctional compound (core) G-(AH) m+n where AH represents an alcohol group, an amino group, or a thiol group, m and n are both integers, and m+n is an integer between 3 and 10; m is an integer between 3 and 8; R1 and R2, independently of one another, each represent a C1-C1 alkyl group uninterrupted or interrupted by one or more oxygen and / or sulfur atoms and / or one or more substituted or unsubstituted imino groups. 18 Alkyl groups, C6-C 12 aryl groups and C5-C 12 or R1 and R2 are each independently a 5- to 6-membered heterocyclic group containing oxygen and / or nitrogen and / or sulfur atoms, which may be substituted with an aryl group, an alkyl group, an aryloxy group, an alkoxy group, a heteroatom and / or a heterocyclic group; R2 may be R1-(C=O)-; Y is O or S; R3 is hydrogen or a C1 to C4 alkyl group.

[0049] Here, the photopolymerization initiator represented by formula (I) does not contain a photocurable ethylenically unsaturated group.

[0050] Preferably, in formula (I), m+n is an integer between 3 and 8, more preferably an integer between 3 and 6. For example, in formula I, m is an integer between 3 and 6, more preferably an integer between 3 and 5.

[0051] In formula (I), when A is oxygen, G-(AH) m+n is a polyhydroxyl group (polyhydroxyl G-(AH) is a hydroxy compound selected from the group consisting of monomeric polyols, oligomeric polyols, and polymeric polyols, and mixtures thereof. When A is sulfur, G-(AH) is a hydroxy compound selected from the group consisting of monomeric polyols, oligomeric polyols, and polymeric polyols, and mixtures thereof. m+n is a polythiol compound. In formula (I), when A is nitrogen, G-(AH) m+n is a linear or branched polyamine. When A is a mixture of oxygen and / or nitrogen and / or sulfur, G-(AH) m+n is a compound containing different functional groups, for example, a compound containing an amino group and a hydroxy group. Residue G- suitable for carrying out the present invention does not contain a photocurable ethylenically unsaturated group. When A is a single bond, G- is represented by the above-exemplified G-(AH). m+nIt is a residue obtained by removing a hydroxy group and / or an amino group and / or a mercapto group from

[0052] Preferably, G-(AH) m+n The number average molecular weight of the copolymer is 1,500 or less, more preferably 800 or less, and even more preferably 500 or less.

[0053] When n is not 0, the compound of formula (I) has an alcoholic radical and / or an amino group and / or a mercapto group.

[0054] Representative tri- or higher functional acylphosphine photopolymerization initiators included in formula (I) are shown in Table 1. Among them, PI-3, PI-4, PI-10, PI-11, PI-12, PI-14, and PI-17 are particularly preferred. By including such tri- or higher functional acylphosphine photopolymerization initiators, outgassing is suppressed, and a cured product with superior insulation reliability can be obtained.

[0055] [Table 1] JPEG2026016443000003.jpg225169JPEG2026016443000004.jpg226170JPEG2026016443000005.jpg183169 JPEG2026016443000006.jpg183170JPEG2026016443000007.jpg218170JPEG2026016443000008.jpg109168

[0056] Such tri- or higher functional acylphosphine photopolymerization initiators can be produced by the method described in Japanese Patent No. 6,599,446, for example.

[0057] Commercially available acylphosphine oxide photopolymerization initiators that can be used include Omnirad TPO manufactured by IGM Resins, and Omnirad 819 and Omnipol TP manufactured by IGM Resins BV.

[0058] Specific examples of the titanocene photopolymerization initiator include bis(cyclopentadienyl)(diphenyl)titanium(IV), bis(cyclopentadienyl)titanium(IV) dichloride, bis(cyclopentadienyl)-bis(2,3,4,5,6-pentafluorophenyl)titanium(IV), bis(cyclopentadienyl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium(IV), etc. Commercially available products include Omnirad 784 manufactured by IGM Resins BV.

[0059] The blending ratio of these photopolymerization initiators (B) is suitably 0.01 to 30 parts by weight, preferably 5 to 25 parts by weight, and more preferably 10 to 20 parts by weight, per 100 parts by weight (solids content) of the vinyl ester resin (A). If the amount of photopolymerization initiator used is less than the above range, the photocurability of the composition will deteriorate, while if it is too much, the properties as a solder resist agent will deteriorate, which is not preferred.

[0060] In this specification, the term "polymer" is a general term that refers to homopolymers, copolymers, and mixtures thereof, and the same applies to other similar expressions.

[0061] (D) Compounds having two or more ethylenically unsaturated groups in one molecule The compound (D) having two or more ethylenically unsaturated groups in one molecule used in the alkaline-developable resin composition of the present invention is a compound that can be photocured by irradiation with active energy rays to insolubilize the vinyl ester resin (A) in an alkaline aqueous solution or to help insolubilize the vinyl ester resin in an alkaline aqueous solution. For example, hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate; Monoacrylates or diacrylates of glycols such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol, and propylene glycol; acrylamides such as N,N-dimethylacrylamide, N-methylolacrylamide, and N,N-dimethylaminopropylacrylamide; aminoalkyl acrylates such as N,N-dimethylaminoethyl acrylate and N,N-dimethylaminopropyl acrylate; polyols such as hexanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, tris(2-hydroxyethyl) isocyanurate, etc., or polyhydric acrylates such as ethylene oxide adducts or propylene oxide adducts thereof; acrylates such as phenoxy acrylate, bisphenol A diacrylate, and ethylene oxide or propylene oxide adducts of these phenols; acrylates of glycidyl ethers such as glycerin diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, and triglycidyl isocyanurate; and melamine acrylate, and at least one of the methacrylates corresponding to the above acrylates.

[0062] Further examples include epoxy acrylate resins obtained by reacting acrylic acid with a polyfunctional epoxy resin such as a cresol novolac epoxy resin, and epoxy urethane acrylate compounds obtained by reacting a half urethane compound of a hydroxy acrylate such as pentaerythritol triacrylate and a diisocyanate such as isophorone diisocyanate with the hydroxyl group of this epoxy acrylate resin.

[0063] The amount of compound (D) having two or more ethylenically unsaturated groups per molecule is preferably 5 to 100 parts by weight, more preferably 10 to 70 parts by weight, per 100 parts by weight (solids content) of the vinyl ester resin (A). If the amount is less than 5 parts by weight per 100 parts by weight of the vinyl ester resin (A), the photocurability of the resulting alkaline-developable resin composition decreases, making it difficult to form a pattern by alkaline development after exposure to active energy rays. On the other hand, if the amount exceeds 100 parts by weight, the solubility in an alkaline aqueous solution decreases, making the cured coating film brittle, which is also undesirable.

[0064] (F) Other additives As described above, the other additives in the present invention refer to additives other than (B) the photopolymerization initiator and (C) the glass powder.

[0065] Examples of such additives include known and commonly used colorants such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black, and acid black; known and commonly used thermal polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, pyrogallol, and phenothiazine; known and commonly used thickeners such as finely divided silica, organic bentonite, and montmorillonite; at least one of silicone-based, fluorine-based, and polymer-based antifoaming agents and leveling agents; imidazole-based, thiazole-based, and triazole-based adhesion promoters; silane coupling agents; phenol-based, phosphorus-based, and sulfur-based antioxidants; hindered amine-based light stabilizers; and dispersants.

[0066] The blending ratio of such (F) other additives is suitably 0.01% by weight or more and 20% by weight or less of the total amount of the alkaline developing resin composition. If it is less than 0.01% by weight, the effect is not sufficiently obtained, while if it exceeds 20% by weight, the printability and hardness of the alkaline developing resin composition are unfavorably deteriorated.

[0067] (G) Epoxy resin In order to impart heat resistance, it is preferable to blend an epoxy resin having at least two epoxy groups in the molecule, i.e., a polyfunctional epoxy resin (G), into the alkaline developing resin composition used in the present invention.

[0068] Commercially available products include bisphenol A epoxy resins such as jER828, jER834, jER1001, and jER1004 manufactured by Mitsubishi Chemical Corporation, EPICLON 840, 850, 850S, 1050, and 2055 manufactured by DIC Corporation, EPOTOTE YD-011, YD-013, YD-127, and YD-128 manufactured by NIPPON STEEL Chemical & Material Co., Ltd., DER317, DER331, DER661, and DER664 manufactured by Dow Chemical Company, and Sumi-Epoxy ESA-011, ESA-014, ELA-115, and ELA-128 manufactured by Sumitomo Chemical Co., Ltd. (all trade names). Brominated epoxy resins such as EPOTOTE YDB-400 and YDB-500 manufactured by Dow Chemical Company, DER542 manufactured by Dow Chemical Company, and Sumi-Epoxy ESB-400 and ESB-700 manufactured by Sumitomo Chemical Co., Ltd. (all trade names); jER152 and jER154 manufactured by Mitsubishi Chemical Corporation, DEN431 and DEN438 manufactured by Dow Chemical Company, EPICLON N-730, EPICLON N-770, and EPICLON N-865 manufactured by DIC Corporation, EPOTOTE YDCN-701 and YDCN-704 manufactured by NIPPON STEEL Chemical & Material Co., Ltd., EPPN-201, EOCN-1025, EOCN-1020, EOCN-104S, RE-306, and NC-3000 manufactured by Nippon Kayaku Co., Ltd., and Sumi-Epoxy manufactured by Sumitomo Chemical Co., Ltd. ESCN-195X, ESCN-220, NIPPON STEEL Chemical & Novolac epoxy resins such as YDCN-700-2, YDCN-700-3, YDCN-700-5, YDCN-700-7, YDCN-700-10, YDCN-704, and YDCN-704A manufactured by Nippon Steel Material Co., Ltd., and EPICLON N-680, N-690, and N-695 manufactured by DIC Corporation (all trade names); EPICLON 830 manufactured by DIC Corporation, jER807 manufactured by Mitsubishi Chemical Corporation, and bisphenol F epoxy resins such as EPOTOTE YDF-170, YDF-175, and YDF-2004 manufactured by Nippon Steel Chemical & Material Co., Ltd. (all trade names); and EPOTOTE manufactured by Nippon Steel Chemical & Material Co., Ltd. Hydrogenated bisphenol A type epoxy resins such as ST-2004, ST-2007, ST-3000 (trade names), and YX8034 manufactured by Mitsubishi Chemical Corporation; glycidylamine type epoxy resins such as jER604 manufactured by Mitsubishi Chemical Corporation, EPOTOTE YH-434 manufactured by NIPPON STEEL Chemical & Material Co., Ltd., and Sumi-Epoxy ELM-120 manufactured by Sumitomo Chemical Co., Ltd. (all trade names); hydantoin type epoxy resins; alicyclic epoxy resins such as CELLOXIDE 2021P manufactured by Daicel Corporation (trade name); trihydroxyphenylmethane type epoxy resins such as YL-933 manufactured by Mitsubishi Chemical Corporation, and EPPN-501 and EPPN-502 manufactured by Nippon Kayaku Co., Ltd. (all trade names); YL-6056, YX-4000, YL- bixylenol or biphenol type epoxy resins or mixtures thereof, such as EBPS-200 manufactured by Nippon Kayaku Co., Ltd., EPX-30 manufactured by ADEKA CORPORATION, and EXA-1514 (trade name) manufactured by DIC Corporation; bisphenol A novolac type epoxy resins, such as jER157S (trade name) manufactured by Mitsubishi Chemical Corporation; tetraphenylolethane type epoxy resins, such as jERYL-931 (trade name) manufactured by Mitsubishi Chemical Corporation; heterocyclic epoxy resins, such as TEPIC (trade name) manufactured by Nissan Chemical Industries, Ltd.; diglycidyl phthalate resins, such as BRENMAR DGT manufactured by NOF Corporation; tetraglycidylxylenoylethane resins, such as ZX-1063 manufactured by NIPPON STEEL Chemical & Material Co., Ltd.; Naphthalene skeleton-containing epoxy resins such as ESN-190 and ESN-360 manufactured by Nippon Steel Corporation, and HP-4032, EXA-4750, and EXA-4700 manufactured by DIC Corporation; glycidyl methacrylate copolymer epoxy resins such as CP-50S and CP-50M manufactured by NOF Corporation; cyclohexylmaleimide and glycidyl methacrylate copolymer epoxy resins; CTBN-modified epoxy resins (e.g., NIPPON STEEL CHEMICAL Examples of epoxy resins include, but are not limited to, YR-102 and YR-450 manufactured by Epoxy Resin Co., Ltd. These epoxy resins may be used alone or in combination of two or more.

[0069] The content of the (G) epoxy resin is preferably 10 to 100 parts by weight, more preferably 20 to 90 parts by weight, and even more preferably 30 to 80 parts by weight, per 100 parts by weight (solid content) of the (A) vinyl ester resin.

[0070] (H) Organic Solvent Regarding the organic solvent (H) used in the alkaline-developable resin composition of the present invention, an organic solvent can be used for the purpose of synthesizing the vinyl ester resin (A), preparing the composition, or adjusting the viscosity when applying the composition to a substrate or a carrier film.

[0071] Examples of such organic solvents include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, and petroleum-based solvents. More specifically, examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, and propylene glycol butyl ether acetate; alcohols such as ethanol, propanol, ethylene glycol, and propylene glycol; aliphatic hydrocarbons such as octane and decane; and petroleum-based solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha. The organic solvents described above can be used alone or in combination.

[0072] When the alkaline developable resin composition of the present invention is used to form a solder resist layer on a printed wiring board, the viscosity is adjusted as necessary to a level suitable for the application method, and then the composition is applied to, for example, a printed wiring board on which a circuit has been previously formed by a method such as screen printing, curtain coating, spray coating, or roll coating, and, if necessary, dried at a temperature of, for example, about 60 to 100°C, thereby forming a tack-free coating film. Next, the composition is selectively exposed to actinic rays through a photomask on which a predetermined exposure pattern has been formed, and the unexposed areas are developed with an alkaline aqueous solution to form a resist pattern. Furthermore, for example, For example, by heating to a temperature of about 140 to 180°C for thermal curing, the curing reaction of the (G) epoxy resin and the polymerization of the (A) vinyl ester resin can be accelerated, and the properties of the resulting resist film can be improved, such as adhesion, thermal shock resistance, heat resistance, solvent resistance, acid resistance, moisture absorption resistance, PCT resistance, adhesion, and electrical properties.

[0073] The alkaline aqueous solution used during the development may be an alkaline aqueous solution of potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, amines, etc. Furthermore, the irradiation light source used for photocuring may suitably be a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a semiconductor laser, a solid-state laser, a xenon lamp, or a metal halide lamp. The alkaline-developable resin composition of the present invention can be used not only by directly applying it in liquid form to a substrate having a copper circuit, but also in the form of a photocurable dry film obtained by previously applying the alkaline-developable resin composition to a carrier film and drying it. The use of the alkaline-developable resin composition of the present invention as a photocurable dry film is shown below. The photocurable dry film has a structure in which a carrier film, a resin layer, and an optional peelable cover film are laminated in this order. The resin layer is obtained by applying the alkaline-developable resin composition of the present invention to the carrier film and drying it. After forming the resin layer on the carrier film, the photocurable dry film is obtained by laminating a cover film on the resin layer. The carrier film is a thermoplastic film such as a polyester film having a thickness of 2 to 150 μm. The resin layer is formed by uniformly applying an alkaline developing resin composition to a carrier film with a blade coater, lip coater, comma coater, film coater, or the like to a thickness of 10 to 150 μm, and then drying the applied composition. The cover film may be a polyethylene film, a polypropylene film, or the like, but it is preferable that the adhesive strength with the resin layer is weaker than that of the carrier film. The cured product of the present invention is obtained by applying an alkaline developable resin composition to copper and drying the composition to obtain a coating film, or by applying the alkaline developable resin composition to a carrier film, drying the composition, laminating the resulting photocurable dry film on copper, and photocuring the resulting coating film. To prepare a cured product on a substrate having a copper circuit using a photocurable dry film, the cover film is peeled off, the resin layer and the substrate having a copper circuit are superimposed, and they are laminated using a laminator or the like to form a resin layer on the substrate having a copper circuit. The formed resin layer can be exposed, developed, and heat-cured in the same manner as above to form a cured product. The carrier film can be peeled off either before or after exposure. The alkaline developable resin composition is suitably used to form a cured film on a printed wiring board, preferably a permanent insulating film, and particularly preferably a solder resist.

[0074] The present invention will be explained in more detail with reference to examples and comparative examples, but the scope of the present invention and its embodiments are not limited thereto. In the examples and comparative examples, "parts" and "%" are by weight unless otherwise specified. The property values ​​of the compositions of the present examples were tested using the methods described below.

[0075] Synthesis Example Into a four-neck flask equipped with a stirrer and a reflux condenser, 214 parts of cresol novolac epoxy resin EPICLON N-695 (manufactured by DIC, epoxy equivalent = 214) were placed, and 103 parts of diethylene glycol monoethyl ether acetate and a petroleum hydrocarbon solvent (manufactured by Japan Energy Corporation, trade name: Cactus Fines 103 parts of SF-01 was added and dissolved by heating. Next, 0.1 parts of hydroquinone as a polymerization inhibitor and 2.0 parts of triphenylphosphine as a reaction catalyst were added to this mixture. The mixture was heated to 95-105°C, and 72 parts of acrylic acid was slowly added dropwise, followed by a 16-hour reaction. The resulting reaction product was cooled to 80-90°C, and 91.2 parts of tetrahydrophthalic anhydride was added and reacted for 8 hours. The resulting mixture was cooled and then removed. The carboxyl group-containing vinyl ester resin thus obtained had a nonvolatile content of 65% and an acid value of 87.5 mgKOH / g of the solid content.

[0076] The vinyl ester resin solution (varnish) from the above Synthesis Example was used to prepare an alkaline developable resin composition by compounding the components and proportions (parts by weight) shown in Table 1, premixing them in a mixer, and then kneading them in a three-roll mill. Furthermore, the adhesion and thermal shock resistance were evaluated by the following methods.

[0077] [Table 1]

[0078] A. Synthesis example of carboxyl group-containing vinyl ester resin, solid content 65%, (5) Equivalent to carboxyl group-containing vinyl ester resin F Pigment: Phthalocyanine Green, manufactured by Dainippon Ink and Chemicals, Inc. t A F. Antifoaming agent: KS-66, manufactured by Shin-Etsu Chemical Co., Ltd. F Dispersant: BYK-110, polymerized phosphate ester, manufactured by BYK-Chemie B Photopolymerization initiator: Omnirad 369 E (chemical name: 2-benzyl-2-di Methylamino-1-(4-morpholinophenyl)butanone, manufactured by IGM C Soft composite glass powder: K10, manufactured by Suzhou Jinyi New Materials Co., Ltd. (SiO2: 62.3~ 62.8%, Fe2O3:0.0149~0.017%, Al2O3:16.9~17.6%, CaO:7.35~7.66%, MgO:1.4~1.54%, B2O3:9.6 ~10.3%) Mohs hardness: 5~6 E Talc: LMP-100, manufactured by FUJI TALC INDUSTRIAL Silica: A-8 Sibelco H Solvent: PGMEA, propylene glycol monomethyl ether 110 acetate G Epoxy resin: N-770-75EA, manufactured by DIC, novolac type multifunctional epoxy Resin, 75% solids D Compounds having two or more ethylenically unsaturated groups in one molecule: MT-3501G , made by Zhangjiagang Dongyadi Ai Biochemical Co., Ltd.

[0079] Performance evaluation (1) Adhesion (Pull off test) The alkaline-developable resin compositions of the Examples and Comparative Examples were applied to the entire surface of a substrate on which a 2 mm copper wire pattern had been formed by screen printing, to a thickness of 40 μm, and then dried in a hot air circulation drying oven at 80°C for 30 minutes. After cooling to room temperature, the coating was exposed to a 300 mJ / cm 2 exposure using an exposure device equipped with a high-pressure mercury lamp. 2The resist was then developed in a 1 wt % aqueous sodium carbonate solution at a pressure of 0.2 MPa and a liquid temperature of 30°C for 60 seconds, and then cured in a hot air circulation drying oven at 150°C for 60 minutes. In this way, a copper circuit board having a cured film was produced. A DeFelsko PosiTest AT digital display pull-off adhesion tester (capable of measuring the adhesion of coatings on metal, concrete, and other materials) was also prepared. A dolly (dimensions: bottom diameter 1 cm) was adhered and fixed (heated at 120°C for 1 hour) to the surface of the cured film (as shown in the image in Figure 3) using an adhesive (LOCTITE ABLESTIK 2332-17 high-strength structural adhesive) manufactured by Emerson & Cumming. The tensile force required to separate the cured film from the copper substrate per unit area was measured, expressed in MPa, according to ATSM D4541. ○: Tensile strength is 6.0 MPa or more. ×: Tensile strength is less than 6.0 MPa.

[0080] (2) Thermal shock resistance The alkaline-developable resin compositions of the Examples and Comparative Examples were applied to the entire surface of a substrate on which a 2 mm copper wire pattern had been formed by screen printing, to a thickness of 40 μm, and then dried in a hot air circulation drying oven at 80°C for 30 minutes. After cooling to room temperature, the coating was exposed to 400 mJ / cm using an exposure device equipped with a high-pressure mercury lamp. 2 The pattern was then developed with a 1 wt% aqueous sodium carbonate solution at a pressure of 0.2 MPa and a liquid temperature of 30°C for 60 seconds, and then cured in a hot air circulation drying oven at 150°C for 60 minutes. The cumulative exposure dose in a UV transfer oven was 2000 mJ / cm. 2 Seventeen substrates with rectangular resist patterns were fabricated for evaluating crack resistance during thermal cycles by irradiating them with ultraviolet light under the conditions described above. Several of the evaluation substrates fabricated in this manner were placed in a temperature cycler that cycled between -40°C and 160°C, and a thermal shock cycle test (TCT test) was performed with different cycle numbers. The appearance was then observed after each cycle, and the maximum number of cycles at which cracks did not occur was recorded (see Figures 1 and 2 for the presence or absence of cracks). The evaluation criteria are shown below. ◯: No cracks were observed even after 1000 or more cycles. △: No cracks occurred after 700 or more and less than 1000 cycles. ×: Cracks occurred within 700 cycles.

[0081] As can be seen from the above, by adjusting the compositions to those of Examples 1 to 3, alkaline developable resin compositions can be obtained that can provide solder resist layers excellent in both thermal shock resistance and adhesive strength. In contrast, Comparative Examples 1 and 2 used only talc and silica as fillers, resulting in low adhesive strength, and Comparative Example 2, which used even less talc, also had poor thermal shock resistance. Comparative Example 3 used only soft composite glass powder, which improved adhesive strength but poor thermal shock resistance. Comparative Example 4 used only silica, which also improved adhesive strength but poor thermal shock resistance. In Comparative Example 5, a soft composite glass powder and silica were used in combination, and the adhesive strength was similarly improved, but the thermal shock resistance was low.

Claims

1. (A) a vinyl ester resin, (B) a photopolymerization initiator, (C) glass powder, (D) a compound having two or more ethylenically unsaturated groups in one molecule, and (E) an inorganic filler, wherein the (E) inorganic filler contains talc; The glass powder (C) contains, in weight percent, SiO ２ :60~65%, Fe ２ O ３ :0.01~0.02%, Al ２ O ３ :14-20%, CaO: 6-9%, MgO: 1-2%, B ２ O ３ : 8 to 12%, and the Mohs hardness of the glass powder (C) is less than 6.5, The alkaline-developable resin composition, wherein the (B) photopolymerization initiator includes at least one of an α-aminoacetophenone-based photopolymerization initiator and a tri- or higher functional acylphosphine-based photopolymerization initiator.

2. 2. The alkaline-developable resin composition according to claim 1, further comprising (F) another additive other than the (B) photopolymerization initiator and the (C) glass powder.

3. 3. The alkaline-developable resin composition according to claim 1, further comprising (G) an epoxy resin.

4. 3. The alkaline-developable resin composition according to claim 1, further comprising (H) an organic solvent.

5. 4. The alkaline-developable resin composition according to claim 3, further comprising (H) an organic solvent.

6. A photocurable dry film obtained by applying the alkaline developable resin composition according to claim 1 or 2 to a carrier film and drying the applied resin composition.

7. 3. A cured product obtained by applying the alkaline developable resin composition according to claim 1 or 2 to copper, drying the applied coating film, or by applying the alkaline developable resin composition to a carrier film, drying the applied coating film, laminating the resulting photocurable dry film on copper, and photocuring the resulting coating film.

8. 3. A printed wiring board comprising: a coating film obtained by applying the alkaline developable resin composition according to claim 1 or 2 to a substrate having a copper circuit and drying the composition; or a cured product obtained by applying the alkaline developable resin composition to a carrier film, drying the composition, laminating the resulting photocurable dry film on a substrate having a copper circuit, photocuring the resulting coating film, and then thermally curing the resulting cured product.

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