TW201307470A - Thermocuring resin composition, dry film and printed wiring board - Google Patents

Abstract

The present invention provides a thermocuring resin composition, a dry film and a printed wiring board using the same for being used as a solder resist composition and having the excellent covering property and characteristics suitable for laser processing. The thermocuring resin composition comprises an epoxy resin (A), a colorant (B) and a curing agent (C); the colorant (B) possesses an absorbance peak within any one or both of the 350-550 nm wavelength range and the 570-700 nm wavelength range, and has absorption at the laser oscillation wavelength used for laser processing.

Description

Thermosetting resin composition, dried film, and printed wiring board

The present invention relates to a thermosetting resin composition, a dry film, and a printed wiring board.

Generally, in a printed wiring board used for an electronic device or the like, when an electronic component is mounted, a resin composition is applied onto a region other than the connection hole on a substrate on which a circuit pattern is formed, and is hardened to form a solder resist. . The solder resist is a conductor that prevents solder from adhering to unnecessary portions while protecting the circuit.

Further, the solder resist also functions as a concealed circuit pattern due to discoloration caused by heat or moisture, or electrical discoloration, damage, contamination, etc., and prevents the appearance of the printed wiring board from deteriorating. Therefore, in order to improve the concealing property, a coloring agent is usually added to the resin composition for forming a solder resist (see, for example, Patent Document 1).

However, in recent years, the printed wiring board has progressed toward the miniaturization of the circuit pattern based on the demand for miniaturization or high functionality of electronic equipment, and accordingly, the solder resist has progressed toward further thinning. As a result, the concealing property of the solder resist is lowered, and the discoloration of the circuit of the lower layer is often observed through the solder resist, and problems associated with poor appearance occur. Therefore, the requirement is that the performance of the solder resist which does not impair the other required performance, but which prevents the appearance from occurring, can be prevented.

Further, when a solder resist pattern is formed on a substrate by using a thermosetting resin composition, the through holes for mounting are usually formed by irradiation of laser light. Therefore The solder resist is suitable for laser processing.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2009-258613 (Patent Patent Application, etc.)

An object of the present invention is to provide a thermosetting resin composition which is excellent in concealability and suitable for laser processing as a composition for a solder resist, a dried film and a printed wiring board using the same.

Further, an object of the present invention is to provide a dried film which can prevent occurrence of appearance defects when used for a solder resist, and a printed wiring board using the same.

As a result of the active review by the inventors of the present invention, it has been found that the above problems can be solved by using a coloring agent formulated with a thermosetting resin composition having a specific absorbance peak and an absorption wavelength as a solder resist, and thus the present invention has been completed.

That is, the thermosetting resin composition of the present invention is a thermosetting resin composition comprising (A) an epoxy resin, (B) a colorant, and (C) a curing agent formed on a copper circuit, and is characterized in that The above (B) colorant is at a wavelength of 350 to 550 nm or 570 to 700 nm. There is a peak of absorbance in either or both of the ranges, and there is an absorber in the oscillation wavelength of the laser used for laser processing.

In the present invention, the laser is preferably selected from any one of a carbon dioxide laser, a UV-YAG laser, and a excimer laser. Furthermore, the thermosetting resin composition of the present invention preferably further contains one or more kinds of (D) inorganic fillers in an amount of 30 to 80% by mass in terms of solid content, and the refractive index and the resin component are The difference in refractive index is 0.05 or more.

Further, the drying mold of the present invention is characterized in that it is provided with a dried coating film of the above-described thermosetting resin composition of the present invention on a carrier film.

Further, the printed wiring board of the present invention is characterized in that it has a cured film which is formed on the substrate on which the circuit pattern is formed, using the thermosetting resin composition of the present invention, or the heat of the carrier film. A cured film formed by drying a film of a dried coating film of a curable resin composition.

As a result of the positive review by the inventors of the present invention, it has been found that the use of a dry film formed of a laminate structure of two or more layers having a function of suppressing the oxidation of copper by using a layer on the side of the coated circuit pattern can be used as a solder resist. The subject matter is thus completed.

That is, another dry film of the present invention is characterized in that the carrier film is provided with a dry coating film which is laminated on a substrate on which a circuit pattern formed of copper is formed, and is characterized by the aforementioned dry coating. The film is formed by a lower layer for suppressing oxidation of copper covering the above circuit pattern, and an upper layer for laser processing and copper circuit hiding on the lower layer laminated on the lower layer, the lower layer being composed of (a) An epoxy resin and (b) a composition comprising a phenol resin.

In the present invention, the epoxy resin (a) preferably contains a resorcinol type epoxy resin. Further, in the invention, at least one of the upper layers is made of a thermosetting resin composition containing (A) an epoxy resin, (B) a colorant, and (C) a curing agent, and the (B) coloring agent is It has a peak of absorbance in either or both of the wavelength range of 350 nm to 550 nm or 570 nm to 700 nm, and has an absorber in the excitation wavelength of the laser used for laser processing.

In the present invention, the laser is preferably any one selected from the group consisting of a carbon dioxide laser, a UV-YAG laser, and a excimer laser. In the dry film of the present invention, the thermosetting resin composition further contains one or two or more kinds of (D) inorganic fillers in an amount of 30 to 80% by mass in terms of solid content, and the refractive index and the resin are The difference in refractive index of the component is 0.05 or more.

Further, another printed wiring board of the present invention is characterized in that the dried coating film on the dried film of the present invention is laminated on a substrate having a circuit pattern formed of copper, and is formed by heat curing.

According to the present invention, it is possible to realize a thermosetting resin composition which is excellent in concealability and a laser processing property as a composition for a solder resist, a dried film using the same, and a printed wiring board.

Moreover, according to the present invention, by using the above configuration, it is possible to realize a dried film which can prevent appearance defects when used for a solder resist, and a printed wiring board using the same.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<First Embodiment>

First, a first embodiment of the present invention will be described.

The thermosetting resin composition according to the first embodiment of the present invention contains (A) an epoxy resin, (B) a colorant, and (C) a curing agent as essential components, and is characterized in that (B) a coloring agent. Those with specific absorbance peaks and absorption wavelengths are used.

Specifically, it is used for peaks having absorbance at a specific wavelength suitable for concealing the oxidation of a copper circuit, and has an absorber for (B) a colorant for a vibration wavelength of a laser used for laser processing. The specific wavelength region described above is as shown in Fig. 1. When the difference in absorbance spectra before and after oxidation of the copper forming the circuit pattern is taken, it corresponds to two wavelength ranges of strong intensity. (B) The coloring agent can effectively conceal the discoloration of the lower layer of the circuit formed of copper by forming a peak having absorbance for at least one of the two wavelength regions. The two wavelength regions are specifically in the range of 350 nm to 550 nm and 570 nm to 700 nm, preferably in the range of 400 nm to 550 nm and 570 nm to 650 nm, more preferably in the range of 430 nm to 530 nm and 580 nm to 640 nm, and more preferably 430 nm. The range of 520 nm and 580 nm to 630 nm is preferably in the range of 460 nm to 500 mm and 580 nm to 620 nm. Further, by making the (B) colorant absorbable to the oscillation wavelength of the laser used for the laser processing, the laser processing of the solder resist can be performed at a lower energy. The lasers used in this laser processing are listed as gas lasers, solid lasers and other industrial applications. A variety of lasers used on the way, better gas lasers are carbon dioxide lasers and excimer lasers. The solid laser is a UV-YAG laser. Better for carbon dioxide lasers and UV-YAG lasers. The oscillation wavelength of these lasers is measured by the method specified in "Safety Standard for Laser Products" of JIS C6802.

In the present embodiment, the coloring agent (B) may have a peak of absorbance at least one of the two wavelength regions and absorbs a vibration wavelength of a laser used in laser processing. It is also possible to combine two or more types as appropriate. The usable coloring agent may be used by mixing a conventional coloring agent such as blue, green, yellow or red, and may be any of a pigment, a dye and a coloring matter. Specific examples thereof include phthalocyanine-based pigment blue 15:1, pigment blue 15:3, and fluorene-based pigment red 177.

Further, even in the case of a coloring agent which does not have a peak of sufficient absorbance in the above two-wavelength region, it may be used in combination of two or more types, and may have a peak of sufficient absorbance of oxidation of the concealed copper circuit. In this case, at least one of the coloring agents used may have an absorption wavelength for the laser generated by the laser processing. (B) The amount of the colorant to be blended is preferably in the range of 0.05 to 5% by mass based on the entire solid content of the composition. When the amount of the coloring agent is less than the above range, sufficient concealability may not be obtained. On the other hand, when it is more than the above range, the thermal properties or electrical properties of the solder resist may be impaired. good.

In the first embodiment of the present invention, the coloring agent (B) may be used as long as it satisfies the above conditions, and the desired effects of the present invention can be obtained, and the points other than the above can be appropriately carried out according to the conventional method. Special restrictions.

As the (A) epoxy resin, for example, a bisphenol A epoxy resin, a bisphenol F epoxy resin, a hydrogenated bisphenol A epoxy resin, a brominated bisphenol A epoxy resin, or a bisphenol S ring is used. Oxygen resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolak type epoxy resin, biphenyl type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin , dicyclopentadiene type epoxy resin, triphenylmethane type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, phosphorus-containing epoxy resin, bismuth type epoxy resin, norbornene An ene type epoxy resin, an adamant type epoxy resin, a fluorene type epoxy resin, an amino phenol type epoxy resin, an amino cresol type epoxy resin, an alkyl phenol type epoxy resin, or the like. These epoxy resins may be used singly or in combination of two or more kinds as appropriate.

In particular, in order to obtain good film characteristics when the obtained composition is used as a dry film, it is preferred to use a mixture of an epoxy resin which is liquid at 20 ° C and an epoxy resin which is solid at 40 ° C as (A) epoxy resin. . The blending amount is preferably in the total amount of the epoxy resin, and the solid epoxy resin is 10 to 80% by mass, preferably 20 to 70% by mass, more preferably 25 to 25% by weight of the epoxy resin at 20 ° C. 60% by mass ratio. The reason for this is that it is difficult to form a film when the amount of the epoxy resin which is liquid at 20 ° C is less than 10% by mass. On the other hand, when it exceeds 80% by mass, the surface of the film is easily roughened. Here, the determination of the "liquid state" in the present invention can be carried out based on the determination method described in JP-A-2010-180355.

The epoxy resin which is liquid at 20 ° C is exemplified by bisphenol A type epoxy resin such as 828 (manufactured by Mitsubishi Chemical Corporation), YD-128 (manufactured by Tohto Kasei Co., Ltd.), 840, 850 (manufactured by DIC Corporation), 806, 807 (Mitsubishi Bisphenol F-type epoxy resin such as YDF-170 (manufactured by Tosho Chemical Co., Ltd.), 830, 835, N-730A (manufactured by DIC Corporation), and bisphenol A such as ZX-1059 (manufactured by Tosho Chemical Co., Ltd.) , F mixture, YX-8000, 8034 (manufactured by Mitsubishi Chemical Corporation), ST-3000 (manufactured by Tosho Chemical Co., Ltd.), hydrogenated bisphenol A type epoxy resin, 630 (manufactured by Mitsubishi Chemical Corporation), ELM-100 (Sumitomo Chemical Co., Ltd.) An alkylphenol type epoxy resin such as an aminophenol type epoxy resin or a HP-820 (manufactured by DIC Corporation) manufactured by the company.

Further, epoxy resins which are solid at 40 ° C are listed, for example, as EPICLON 1050, EPICLON 3050 (manufactured by DIC Corporation), EPICOTE 1001, EPICOTE 1002, EPICOTE 1003 (manufactured by Mitsubishi Chemical Corporation), EPOTOT YD-011, and EPOTOT YD-012 ( Bisphenol F type epoxy resin such as bisphenol A type epoxy resin manufactured by Dongdu Chemical Co., Ltd., EPOTOT YDF-2001, EPOTOT 2004 (manufactured by Tosho Kasei Co., Ltd.), YDB-400 (manufactured by Tohto Kasei Co., Ltd.), EPICLON 152 , bismuth bisphenol A type epoxy resin such as 153 (manufactured by DIC Corporation), bisphenol S type epoxy resin such as EXA-1514 (manufactured by DIC Corporation), N-770, 775 (manufactured by DIC Corporation), EPPN- Phenolic novolac type epoxy resin such as 201H, RE-305 (manufactured by Nippon Kayaku Co., Ltd.), 152, 154 (manufactured by Mitsubishi Chemical Corporation), EOCN-102S, 103S, 104S (manufactured by Nippon Chemical Co., Ltd.), YDCN-701, 702, 703, 704 (manufactured by Tohto Kasei Co., Ltd.), N-660, 670, 680 (manufactured by DIC Corporation), etc., cresol novolac type epoxy resin, 157S70 (manufactured by Mitsubishi Chemical Corporation), N-865 (manufactured by DIC Corporation) Bisphenol A novolac type epoxy resin , N-type epoxy resin such as YX-4000 (manufactured by Mitsubishi Chemical Corporation), NC-3000 (manufactured by Nippon Kayaku Co., Ltd.), naphthalene type epoxy resin such as NC-7000L (manufactured by Nippon Kayaku Co., Ltd.), HP- Dicyclopentadiene type epoxy resin such as 7200 (manufactured by DIC Corporation) and XD-1000 (manufactured by Nippon Kayaku Co., Ltd.), EPPN-501H, 502H (manufactured by Nippon Kayaku Co., Ltd.), 1031S (manufactured by Mitsubishi Chemical Corporation), A triphenylmethane type epoxy resin or the like such as HP-5000 (manufactured by DIC Corporation).

Further, the (A) epoxy resin preferably contains a resorcinol type epoxy resin. When the resorcinol type epoxy resin is used, oxidation of the copper circuit is suppressed, and the effect of lowering the appearance is suppressed. In particular, there is a remarkable effect when forming a film. The resorcinol type epoxy resin is exemplified by, for example, EX-201 (manufactured by Nagase Chemtex Co., Ltd.).

As the (C) hardener, various epoxy resin hardeners or epoxy resin hardening accelerators conventionally known can be used as the epoxy hardener. Specific examples thereof include a phenol resin, an imidazole compound, a polycarboxylic acid and an acid anhydride thereof, a cyanate resin, an active ester resin, an acid anhydride, an aliphatic amine, an alicyclic polyamine, an aromatic polyamine, a tertiary amine, and a dicyandiamide. Amidoxime, anthracene, or such epoxy addition or microencapsulation, and an organophosphine compound such as triphenylphosphine, tetraphenylphosphonium or tetraphenylborate, DBU or a derivative thereof, etc. The hardener or the hardening accelerator is not limited, and may be used singly or in combination of two or more.

In the epoxy curing agent, a phenol resin or an imidazole compound, a polycarboxylic acid or an anhydride thereof, a cyanate resin, an active ester resin or the like is preferably contained, and preferably a phenol resin or an imidazole compound, and further preferably contains at least a phenol resin. to For the phenol resin or the like, a phenol novolak resin, an alkylphenol novolak resin, a bisphenol A novolak resin, a dicyclopentadiene type phenol resin, a phenol aralkyl (Xylok) type phenol resin, a terpene may be used alone. A conventional phenol resin, a cresol/naphthol resin, a polyvinyl phenol, a phenol/naphthol resin, or the like may be used, or two or more types may be used in combination.

Specific examples of the phenol resin are PHENOLITE TD-2090, PHENOLITE 2131, BESMOL CZ-256-A (manufactured by DIC Corporation), SHONOL BRG-555, SHONOL BRG-556 (manufactured by Showa Denko Co., Ltd.), MIREX XLC-4L, MIREX XLC. -LL (manufactured by Mitsui Chemicals, Inc.), PP-700, PP-1000, DPP-M, DPP-3H, DPA-145, DPA-155 (manufactured by Nippon Petrochemical Co., Ltd.), SK-Resin HE100C, SK-Resin HE510 , SK-Resin HE900 (manufactured by Sumitomo Chemical Co., Ltd.), HF-1M, HF-3M, HF-4M, H-4 (manufactured by Minwa Kasei Co., Ltd.), NHN, CBN (manufactured by Nippon Kayaku Co., Ltd.), HPC-9500 (DIC) These phenol resins may be used singly or in combination of two or more kinds as appropriate.

The phenol resin is preferably blended in such a ratio that the ratio of the epoxy group in the epoxy resin of (A) to the hydroxyl group in the phenol resin is hydroxy/epoxy (equivalent ratio) = 0.2 to 2. By making the hydroxyl group/epoxy group (equivalent ratio) within the above range, the roughening of the surface of the film in the desmear step can be prevented. More preferably, it is a hydroxyl group/epoxy group (equivalent ratio) = 0.2 to 1.5, more preferably a hydroxyl group/epoxy group (equivalent ratio) = 0.3 to 1.0.

The polycarboxylic acid and an acid anhydride thereof are a compound having two or more carboxyl groups in one molecule and an acid anhydride thereof, and are exemplified by a copolymer of (meth)acrylic acid, for example. A copolymer of maleic anhydride, a condensate of a dibasic acid, or the like, and a resin having a carboxylic acid terminal such as a carboxylic acid terminal quinone imine resin. Commercially available products are JONCRYL (commodity group name) manufactured by BASF Corporation of Japan, SMA Resin (commodity group name) manufactured by SARTOMER Co., Ltd., manufactured by Lipopolymer of Nippon Chemical Co., Ltd., and V-8000, V manufactured by DIC Corporation. a carboxylic acid terminal polyimine resin such as -8002.

The above cyanate resin is a compound having two or more cyanate groups (-OCN) in one molecule. Any of the cyanate resins can be used. The cyanate resin is exemplified by, for example, a phenol novolak type cyanate resin, an alkylphenol novolac type cyanate resin, a dicyclopentadiene type cyanate resin, a bisphenol A type cyanate resin, and a bisphenol. F-type cyanate resin, bisphenol S-type cyanate resin. Further, it may be a part of the triazine-formed prepolymer. Commercially available products of cyanate resin are phenol phenol varnish type polyfunctional cyanate resin PT30 manufactured by Japan LONZA Co., Ltd., and partially triazineated prepolymer of bisphenol A type dicyanate manufactured by Japan LONZA Co., Ltd. BA230, cyanate resin DT-4000, DT-7000, etc., which has a dicyclopentadiene structure manufactured by LONZA Corporation of Japan.

The above active ester resin is a resin having two or more active ester groups in one molecule. The active ester resin can be obtained by a condensation reaction of a carboxylic acid compound with a hydroxy compound. Among them, an active ester compound obtained by using a phenol compound or a naphthol compound as a hydroxy compound is preferred. Phenol compounds or naphthol compounds are exemplified by hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phthalin, methylated bisphenol A, methylated bisphenol F, methyl Bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, --naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxyl Benzophenone, fluoroglycine, benzenetriol, dicyclopentadiene diphenol, phenol novolak resin, and the like. Commercially available active ester compounds are, for example, EXB-9451, EXB-9460 manufactured by DIC Corporation, DC808, YLH1030 manufactured by Mitsubishi Chemical Corporation, and the like.

The amount of the curing agent (C) is preferably in the range of 1 to 70 parts by mass based on 100 parts by mass of the (A) epoxy resin in terms of solid content. (C) When the amount of the curing agent is less than the above range, the curing may be insufficient. On the other hand, if the amount is more than the above range, the curing effect may not be increased, and particularly the heat resistance may be impaired. The problem of mechanical strength is therefore poor. More preferably from 5 to 65 parts by mass, more preferably from 10 to 50 parts by mass.

In the thermosetting resin composition of the present embodiment, in addition to the above (A) epoxy resin, (B) colorant, and (C) curing agent, (D) an inorganic filler is preferably further prepared. The (D) inorganic filler is preferably one in which the difference between the refractive index of the resin component and the refractive index of the resin component is 0.05 or more. The concealability of the composition can be further improved by using an inorganic filler having a large difference in refractive index from the resin component. Here, the resin component in the present invention means a mixture of resins contained in the composition based on the (A) epoxy resin. In general, since the refractive index of the resin component is from 1.51 to 1.59, the refractive index of the inorganic filler is preferably 1.46 or less or 1.64 or more. Further, in the present embodiment, it is preferred to use (D) an inorganic filler which is excellent in laser workability.

The difference between the refractive index and the refractive index of the resin component is 0.05 or more. As the (D) inorganic filler, for example, barium sulfate (refractive index: 1.64), cerium oxide (refractive index: 1.46), alumina (refractive index: 1.76), titanium oxide (refractive index: 2.52), or the like can be used. Further, the (D) inorganic filler which is excellent in laser workability has a strong absorption peak in the wavelength band of the carbon dioxide laser, and the residue of the inorganic filler which is formed when the through hole is formed is not easily left, and is preferably sulfuric acid. It is preferably barium sulfate or the like, and it is more preferably barium sulfate as the residue does not remain. These inorganic fillers may be used singly or in combination of two or more.

Further, a metal oxide such as mica or alumina or a metal hydroxide such as aluminum hydroxide can also be used.

(D) The amount of the inorganic filler to be blended is preferably from 30 to 80% by mass in terms of solid content. When the amount of the inorganic filler is less than the above range, there is a problem that the film properties such as the hardness of the cured film obtained by using the composition or the dried film formed from the composition are insufficient, and the laser processability is improved. Also low. On the other hand, when the amount of the inorganic filler is more than this range, peeling occurs at the interface at the time of lamination with the resin film, which may cause cracking. Moreover, the coating property of the advection property or the like is deteriorated, and degranulation occurs from the side or the periphery of the through hole in the drilling step after the laser processing, and the shape of the through hole becomes unstable. The blending amount of the inorganic filler is preferably from 30 to 70% by mass, more preferably from 35 to 70% by mass. Further, the average particle diameter of the inorganic filler is preferably 0.01 μm or more and less than 10 μm, more preferably 0.05 μm or more and less than 5 μm, and more preferably 0.1 μm or more is less than 2 μm.

The thermosetting resin composition of the present embodiment may further be formulated with benzene Oxygen resin, hardening catalyst, additives, solvents, etc.

The phenoxy resin can be formulated to improve film formation, and is exemplified by, for example, 1256, 4250, 4275, YX8100BH30, YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), YP50, YP50S, YP55U, YP70, ZX-1356-2, FX-316, YPB- 43C, ERF-001M30, YPS-007A30, FX-293AM40 (manufactured by Dongdu Chemical Co., Ltd.). These phenoxy resins may be used singly or in combination of two or more.

As the hardening catalyst, dicyandiamide, an aromatic amine, an imidazole, an acid anhydride or the like can be used. Specific examples thereof are imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2- Imidazole derivatives such as phenylimidazole, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; dicyanodiamide, benzyldimethylamine, 4-(dimethylamine Amine compounds such as N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N,N-dimethylbenzylamine a bismuth compound such as diammonium adipate or bismuth sebacate; a phosphorus compound such as triphenylphosphine; and a commercially available product such as 2MZ-A and 2MZ manufactured by Shikoku Chemical Industry Co., Ltd. OK, 2PHZ, 2P4MHZ (all trade names of imidazole compounds), U-CAT3503N manufactured by SAN-APRO Co., Ltd., U-CAT3502T (trade names of block isocyanate compounds of dimethylamine), DBU, DBN, U-CATSA102, U-CAT5002 (both bicyclic hydrazine compounds and salts thereof). These hardening catalysts may be used singly or in combination of two or more kinds as appropriate.

Further, ruthenium, acetamidine, benzoquinone, melamine, 2,4-diamino-6-methylpropenyloxyethyl-S-triazine, 2-vinyl-4,6-di can also be used. amine Base-S-triazine, 2-vinyl-4,6-diamino-S-triazine. Isohydrocyanate adduct, 2,4-diamino-6-methylpropenyloxyethyl-S-triazine. An S-triazine derivative such as an isocyanurate adduct is preferably used in combination with a thermosetting catalyst to have a function as a function of the adhesion imparting agent.

In the thermosetting resin composition of the present invention, a urethane-based catalyst can be further added. The urethane-based catalyst preferably uses one or more kinds of amine groups selected from the group consisting of a tin-based catalyst, a metal chloride, a metal acetylacetonate, a metal sulfate, an amine compound, and an amine salt. Acidification catalyst.

The tin-based catalyst is exemplified by an organic tin compound such as tin octylate or dibutyltin dilaurate, or an inorganic tin compound.

The metal salt compound is exemplified by a metal chloride selected from the group consisting of Cr, Mn, Co, Ni, Fe, Cu, and Al, such as cobalt chloride, nickel chloride, iron chloride, and the like.

The above metal ethyl pyruvate is an ethyl phthalate pyruvate of a metal selected from the group consisting of Cr, Mn, Co, Ni, Fe, Cu and Al, and is exemplified by, for example, cobalt acetylacetonate, acetamidine. Nickel pyruvate, iron acetylacetonate, and the like.

The metal sulfate is exemplified by a sulfate selected from the group consisting of Cr, Mn, Co, Ni, Fe, Cu, and Al, and is exemplified by, for example, copper sulfate.

Further, in the present invention, a metal compound can be used as a reaction catalyst. In particular, cobalt acetyl acetonate is preferred, and the amount of the metal compound added is preferably from 10 to 500 ppm in terms of metal with respect to the thermosetting resin composition. It is in the range of 25 to 200 ppm.

As for the additive, at least one of a defoaming agent such as a polyfluorene-based system, a fluorine-based polymer, and a polymer, and a flow-through agent, a hydroxybenzophenone, a hydroxybenzoic acid ester, a benzotriazole, and a cyano group. Ultraviolet absorbers such as acrylates, trishydroxymethane epoxy resins, oxime hydroxyethane epoxy resins or polyimine resins, epoxy, vinyl, acrylic, methacrylic, and amine based systems A conventionally used additive such as a decene coupling agent such as a phenyl group, a thiol type, an imidazole type, a thiazole type or a triazole type, a rheology modifier, an antioxidant, or a rust preventive agent.

As the solvent, ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, and the like can be used. More specifically, ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, and carbene Alcohol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether and other glycol ethers; ethyl acetate, butyl acetate , dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol diethyl ether acetate, propylene glycol butyl ether acetate, methyl lactate, ethyl lactate, butyl lactate and the like; ethanol, propanol, An alcohol such as ethylene glycol or propylene glycol; an aliphatic hydrocarbon such as octane or decane; a petroleum solvent such as petroleum ether, petroleum brain, hydrogenated petroleum brain or solvent naphtha. These solvents may be used singly or in combination of two or more kinds as appropriate. Further, the amount of the solvent to be blended is selected based on the printability of the composition or the film formability.

The dried film of the present embodiment is provided with the hot hardening of the above embodiment. The chemical resin composition is coated on a carrier film and dried to dry the coating film. In other words, the thermosetting resin composition of the present embodiment can be applied onto a carrier film, dried, and optionally wound while laminating the protective film to form a dried film.

As the material of the carrier film, polyethylene terephthalate (PET) is preferably used, and polyester such as polyethylene naphthalate or the like, polypropylene (PP), polycarbonate, polymethacrylic acid can be used. Methyl ester (PMMA), cyclic polyolefin, triethyl fluorenyl cellulose, polyether thioether, polyether ketone, polyimide, and the like. The thickness of the carrier film is preferably from 8 to 60 μm. The thinner the thickness of the carrier film, the higher the laser processability when processed from the carrier film, but when the thickness is less than 8 μm, it is difficult to suppress the damage caused by the laser irradiation around the through hole. On the other hand, when the thickness of the carrier film exceeds 60 μm, the transmittance of the laser light is lowered to reduce the opening diameter. The thickness of the carrier film is preferably from 10 to 50 μm, more preferably from 12 to 38 μm.

As the material of the protective film, the same as those used in the carrier film can be used, and it is preferably PET or PP. The thickness of the protective film is preferably from 5 to 50 μm. When the thickness of the protective film is less than 5 μm, the workability tends to deteriorate when the protective film is laminated. On the other hand, when the thickness of the protective film exceeds 50 μm, the winding diameter is too large when it is in the form of a dry film, and it becomes difficult to transport. operating. The thickness of the protective film is preferably from 8 to 38 μm, more preferably from 10 to 30 μm.

Here, as a method of applying the thermosetting resin composition, a method such as a dip coating method, a flow coating method, a roll coating method, a bar coating method, a screen printing method, or a curtain coating method can be used. In addition, the volatilization drying method uses a hot air circulation type drying furnace, an IR (infrared) furnace, a heating plate, a convection oven, etc. As the heat source using the steam air heating method, a method of bringing the hot air in the dryer into contact with the flow and a method of blowing the nozzle from the nozzle to the support may be used.

In addition, the printed wiring board of the present embodiment has a cured film obtained by using the thermosetting resin composition of the present embodiment or a dried film on the substrate on which the circuit pattern is formed. Here, the printed wiring board of the present embodiment can be produced by using the thermosetting resin composition of the above-described embodiment, and the dried film of the above-described embodiment can be used. The manufacturing method is described below.

First, the substrate on which the circuit pattern is formed is subjected to a pretreatment such as de-esterification or soft etching. Subsequently, a thermosetting resin composition adjusted to a viscosity suitable for the coating method using an organic solvent is applied onto the substrate so that the dry film thickness is 10 to 50 μm. Next, the organic solvent contained in the composition is volatilized and dried (temporarily dried) at a temperature of 40 to 120 ° C to form a dry coating film having no tackiness.

Further, in the step of forming the dried coating film, a dry coating film can be formed by laminating the dried film of the above embodiment on a substrate. In this case, the laminated carrier film may be peeled off at any stage after lamination, after heat hardening, or after laser processing or desmear treatment.

Next, the substrate on which the dried coating film is formed is heated at 130 to 200 ° C for 30 to 120 minutes, and thermally cured to form a cured film (resin insulating layer). Next, a laser-forming via hole is irradiated at a position corresponding to a specific position on the substrate on which the circuit insulating layer of the resin insulating layer thus formed is formed, and the printed wiring board can be manufactured by exposing the circuit wiring.

At this time, there is an unremoved residue on the circuit wiring board in the through hole. In the case of sub-drilling, the decontamination treatment using a permanganate solution or the like is used to decompose the drill to perform the desmear treatment. The desmear treatment can use plasma. In the plasma treatment, for example, a vacuum plasma device, a normal piezoelectric slurry device, or the like can be used, and a plasma using a gas such as oxygen or argon, helium or carbon tetrafluoride, and the like of the mixed gas can be used. A conventional plasma such as pulp.

In addition, even if it is a double-sided board|substrate or a multilayer board, if a thermosetting resin composition is formed like the above, or a cured film is formed using a dry film, and a through-hole is formed by laser-

The printed wiring board manufactured in this manner can be further subjected to gold plating to the circuit wiring, or after the pre-welding process, the electronic components such as the mounted semiconductor die are bonded and mounted by gold bumps or solder bumps.

(Second embodiment)

Next, a second embodiment of the present invention will be described.

The dried film of the second embodiment of the present invention is a dry coating film comprising a circuit pattern formed by forming a circuit pattern formed of copper on a carrier film and thermally cured to form a printed wiring board.

The dry coating film in the dried film of the present embodiment is composed of a layer having a coating circuit pattern for suppressing oxidation of copper, and a layer for laser processing and concealing copper circuits laminated on the lower layer ( Hereinafter, a laminate structure in which one layer is used and each layer including two or more layers is "upper layer" is formed, and the lower layer is formed of (a) an epoxy resin and (b) a composition containing a phenol resin. By making the underlying layer of the covered circuit pattern a function of suppressing copper oxidation, the oxidation of the copper circuit can be suppressed, and the appearance is prevented. Good happening. On the other hand, the upper layer laminated thereon does not impart this function, and it can be obtained as a solder resist by being made of a resin composition for a general solder resist having laser processability and concealability. Other dry films that require performance.

In the present embodiment, the dried film is a dried coating film having a laminated structure of two or more layers, and the reason why the lower layer has an oxidation suppressing function is as follows. That is, the reason is that the effect of the present invention can be obtained if the lower layer of the coated circuit pattern has an oxidation suppressing function, and relatively, even if the upper layer has an antioxidant function, no further effect can be obtained, and the degree of freedom of the upper layer design can be improved, and It can have both the above oxidation inhibition function and the required characteristics as a solder resist.

In the dried film of the present embodiment, the dry coating film formed of the laminated structure may be one that satisfies the above conditions as long as the lower layer satisfies the above conditions, and the desired effect of the present invention can be obtained according to the conventional method. There are no special restrictions on implementation.

In the present embodiment, the upper layer is a resin composition for a general solder resist, and is not particularly limited as long as it satisfies the required characteristics as a solder resist. The upper layer is at least one layer, and may be, for example, 1 to 5 layers, preferably 1 to 3 layers, more preferably 1 layer. The composition of each of the two or more layers may be the same or different. Preferably, at least one of the upper layers is composed of a thermosetting resin composition containing (A) an epoxy resin, (B) a colorant, and (C) a curing agent.

The (A) epoxy resin can be used in the same manner as in the first embodiment described above, and is not particularly limited, and may be used singly or in combination of two or more.

The (B) coloring agent may be appropriately selected from conventionally used pigments, dyes, pigments, and the like, such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, and the like. There are no special restrictions. (B) The coloring agent may be used alone or in combination of two or more.

In the present embodiment, as the coloring agent (B), it is preferable to use a peak having absorbance in a range of one or both of wavelengths of 350 nm to 550 nm and 570 nm to 700 nm, and a thunder used for laser processing. The emission vibration wavelength has an absorber. Preferably, it is in the range of 400 nm to 550 nm and 570 nm to 650 nm, more preferably in the range of 430 nm to 530 nm and 580 nm to 640 nm, and more preferably in the range of 430 nm to 520 nm and 580 nm to 630 nm, preferably 460 nm to 500 nm and 580 nm to 620 nm. The scope. The two-wavelength region is as shown in FIG. 1, and the difference between the absorbance spectra before and after oxidation of the copper forming the circuit pattern can be taken, corresponding to two wavelength ranges of strong intensity. Therefore, the (B) coloring agent can effectively conceal the discoloration of the circuit formed of copper in the lower layer by forming a peak having absorbance in at least one of the two wavelength regions. Further, the coloring agent (B) has an absorption of a vibration wavelength of a laser used for laser processing, and laser processing of a solder resist can be performed at a lower energy. The lasers used in the laser processing are listed as gas lasers, solid lasers, and various lasers used in other industrial applications. The preferred gas lasers are carbon dioxide lasers and excimer lasers. The solid laser is a UV-YAG laser. Better for carbon dioxide lasers and UV-YAG lasers. The oscillation wavelength of these lasers is measured by the method specified in "Safety Standard for Laser Products" of JIS C6802.

In this embodiment, the (B) colorant is in the above two-wavelength region. When at least one of the domains has a peak of absorbance and absorbs the vibrational wavelength of the laser used in the laser processing, one type may be used alone or two or more types may be used in combination. The coloring agent which can be used may be used by mixing a conventional coloring agent such as blue, green, yellow or red, or may be any of a pigment, a dye and a coloring matter. Specific examples thereof include phthalocyanine-based pigment blue 15:1, pigment blue 15:3, and fluorene-based pigment red 177.

Further, even in the case of a coloring agent which does not have a peak of sufficient absorbance in the above two-wavelength region, it may be used in combination of two or more types, and may have a peak of sufficient absorbance of oxidation of the concealed copper circuit. In this case, at least one of the coloring agents used may have an absorption wavelength for the laser generated by the laser processing. (B) The amount of the colorant to be blended is preferably in the range of 0.05 to 5% by mass based on the total amount of the composition. When the amount of the coloring agent is less than the above range, sufficient laser processing property and concealability may not be obtained. On the other hand, when it is more than the above range, thermal properties or electrical properties as a solder resist may be impaired. After all, it is not good.

The (C) curing agent can be used as the epoxy curing agent in the same manner as in the first embodiment, and is not particularly limited. The curing agent or the curing accelerator may be used singly or in combination of two or more kinds as appropriate.

The epoxy curing agent is preferably a phenol resin or an imidazole compound, a polycarboxylic acid and an acid anhydride thereof, a cyanate resin, an active ester resin, etc., and particularly preferably contains a phenol resin or an imidazole compound, and further preferably contains at least a phenol resin. . The phenol resin or the like can be used in the same manner as in the first embodiment described above, and is not particularly limited, and may be used singly or in combination as appropriate. Used on. Further, the specific examples of the phenol resin and the conditions of the blending ratio are also the same as those of the first embodiment, and are not particularly limited. Further, the amount of the curing agent (C) may be the same as that of the first embodiment described above, and is not particularly limited.

In addition to the above (A) epoxy resin, (B) coloring agent, and (C) curing agent, the (D) inorganic filler is preferably further prepared in the thermosetting resin composition constituting the upper layer. The (D) inorganic filler is the same as the first embodiment described above, and it is preferred to use a difference between the refractive index and the refractive index of the resin component of 0.05 or more. The concealability of the composition can be further improved by using an inorganic filler having a large difference in refractive index from the resin component.

The (D) inorganic filler and the (D) inorganic filler excellent in laser processability can be used in the same manner as in the first embodiment, and the difference between the refractive index and the refractive index of the resin component is 0.05 or more. It is particularly limited and may be used singly or in combination of two or more.

Further, similarly to the first embodiment, a metal oxide such as mica or alumina or a metal hydroxide such as aluminum hydroxide may be used.

(D) The conditions of the preferable blending amount and average particle diameter of the inorganic filler may be the same as those in the first embodiment described above, and are not particularly limited.

The thermosetting resin composition constituting the upper layer may be the same as the first embodiment described above, and may further contain a phenoxy resin, a curing catalyst, an additive, a solvent, and the like.

The phenolic oxy-resin, the curing catalyst, the additive, and the solvent are also appropriately used in the same manner as in the first embodiment, and are not particularly limited.

Then, as long as the lower layer contains (a) an epoxy resin and (b) a phenol resin, the function of suppressing oxidation of copper can be exhibited, and in addition to the above, it can be composed of a resin for use with a general solder resist. A resin composition of the same composition.

In the present embodiment, the (a) epoxy resin preferably contains a resorcinol type epoxy resin, and the resorcinol type epoxy resin and other epoxy resins can be used in combination as appropriate. When a resorcinol type epoxy resin is used, the effect of suppressing oxidation of a copper circuit and suppressing deterioration of the appearance is obtained. In particular, there is a remarkable effect when forming a film. The resorcinol type epoxy resin is exemplified by, for example, EX-201 (manufactured by Nagase Chemtex Co., Ltd.). The other epoxy resin may be appropriately selected from one or a combination of two or more of the above (A) epoxy resins, and is not particularly limited.

(b) The phenol resin is appropriately selected from one or a combination of two or more kinds of the phenol resins listed in the above (C) curing agent, and is not particularly limited.

Further, the (b) phenol resin is preferably such that the ratio of the epoxy group in the epoxy resin (a) to the hydroxyl group in the (b) phenol resin is a ratio of a hydroxyl group/epoxy group (equivalent ratio) = 0.2 to 2 Provisioning. Further inhibition of copper oxidation can be achieved by making the hydroxyl group/epoxy group (equivalent ratio) within the above range. More preferably, it is a hydroxyl group/epoxy group (equivalent ratio) = 0.2 to 1.5, more preferably a hydroxyl group/epoxy group (equivalent ratio) = 0.3 to 1.0.

The resin composition constituting the lower layer may be composed of the same components as the upper layer, in addition to the (a) epoxy resin and the (b) phenol resin, and is preferably composed of a thermosetting resin composition. The resin composition constituting the lower layer may also be formulated with an antioxidant as an additive.

The antioxidant is not particularly limited, and is preferably a hindered phenol compound. Hindered phenolic compounds are listed as NOCRAC 200, NOCRAC M-17, NOCRAC SP, NOCRAC SP-N, NOCRAC NS-5, NOCRAC NS-6, NOCRAC NS-30, NOCRAC 300, NOCRAC NS-7, NOCRAC DAH (all of the above) Manufactured for Dae Ning Xin Chemical Industry Co., Ltd.); MARK AO-30, MARK AO-40, MARK AO-50, MARK AO-60, MARK AO616, MARK AO-635, MARK AO-658, MARK AO-15, MARK AO -18, MARK 328, MARK AO-37 (all of which are manufactured by ADEKA ARGUS Chemical Co., Ltd.); Irganox 245, Irganox 259, Irganox 565, Irganox 1010, Irganox 1035, Irganox 1076, Irganox 1081, Irganox 1098, Irganox 1222, Irganox 1330 Irganox 1425WL (all of which are manufactured by BASF Corporation of Japan).

Further, the same pigment as that used above may be used in the lower layer. It is effective to effectively conceal the discoloration aspect of the copper circuit.

The dried film of the present embodiment can be produced by sequentially applying a resin composition constituting each of the upper layer and the lower layer to a carrier film, drying it, and if necessary, laminating the protective film to form a dry coating film having a two-layer structure. .

The material of the carrier film and the protective film can be suitably used in the same manner as in the first embodiment described above, and is not particularly limited. Further, the method of applying the resin composition described above can be carried out in the same manner as in the first embodiment described above, and is not particularly limited.

Further, the printed wiring board of the present embodiment has a pattern in which a dry coating film on the dried film is laminated on a circuit pattern formed of copper, and A hardened film that has been hardened by heat. The manufacturing method is described below.

First, the substrate on which the circuit pattern is formed is subjected to a pretreatment such as de-esterification or soft etching. Subsequently, the dried film of the present embodiment was laminated on the substrate to form a dry coating film which was not sticky to the substrate. Further, the laminated carrier film may be peeled off at any stage after lamination, after heat hardening, after laser processing, or after desmear treatment.

Next, the substrate on which the dried coating film is formed is heated at 130 to 200 ° C for 30 to 120 minutes, and thermally cured to form a cured film (resin insulating layer). Next, a laser-forming via hole is irradiated at a position corresponding to a specific position on the substrate on which the circuit insulating layer of the resin insulating layer thus formed is formed, and the printed wiring board can be manufactured by exposing the circuit wiring.

At this time, when there is a residual component (drilling) which is not removed in the wiring board on the via hole, the desmear treatment can be performed in the same manner as in the first embodiment.

Further, even in the case of a double-sided substrate or a multilayer substrate, if a cured film is formed using a dried film as described above and a through hole is formed by laser, the desmear treatment may be performed as desired.

The printed wiring board thus manufactured can be further subjected to gold plating to the circuit wiring, or after the pre-welding process, the electronic components such as the mounted semiconductor die can be bonded and mounted by gold bumps or solder bumps.

[Examples]

Hereinafter, the present invention will be described in more detail by way of examples.

<Example 1>

The components shown in the following table were blended, premixed with a stirrer, and kneaded using a triaxial roller mill to prepare thermosetting resin compositions of the respective examples and comparative examples.

*1-3) Naphthol type epoxy resin (manufactured by DIC Corporation, epoxy equivalent 135-165)

*1-4) 60% cyclohexanone solution of cresol novolac type epoxy resin (manufactured by DIC, epoxy equivalent 200-230)

*1-5) 60% cyclohexanone solution of phenol novolac resin (manufactured by DIC Corporation, s.p. 78-82 ° C)

*1-6) Cyclooxyl resin (made by Mitsubishi Chemical Corporation), 30% solid solution of cyclohexanone

*1-7) Pigment Blue 15:3 (UV-vis spectrum (Figure 2), IR spectrum (Figure 5))

*1-8) Pigment Yellow 147 (UV-vis spectrum (Fig. 3), IR spectrum (Fig. 5))

*1-9) Pigment Red 177 (UV-vis spectrum (Fig. 4))

*1-10) Spherical cerium oxide (manufactured by Admatechs)

*1-11) Barium sulfate (manufactured by Dai Chemical Co., Ltd.)

*1-12) Imidazole (manufactured by Shikoku Chemical Industry Co., Ltd.)

*1-13) Solvent

*1-14) is a mixture of *1-1, *1-3, *1-4, *1-5, *1-6 (Examples 1-5 are *1-2, *1-3, * 1-4, *1-5, *1-6 mixture) refractive index

*1-15) Pigment Blue 15:1 (UV-vis spectrum (Figure 7), IR spectrum (Figure 8))

(Examples 1-1 to 1-6, Comparative Examples 1-1 to 1-2)

The thermosetting resin composition prepared in Table 1 was sequentially applied to a polyethylene terephthalate (PET) film having a thickness of 38 μm by using an applicator so that the film thickness after drying was 30 μm. The film was dried at 90 ° C to prepare each dried film.

Next, a double-sided copper-clad laminate (MCL-E-679FGR, manufactured by Hitachi Chemical Co., Ltd.) of 400 mm × 300 mm × 0.8 mm thick formed with a conductive layer having a copper thickness of 18 μm was used as a circuit substrate by using a treating agent (CZ- 8100+CL-8300, manufactured by Merck Co., Ltd.) pre-implementation treatment to form a profile having a copper etching amount of 1 μm. A two-chamber vacuum laminator (CVP-300, manufactured by Nichigo Mortor Co., Ltd.) was used to laminate the respective dried films to the pre-treatment conditions at a lamination temperature of 100 ° C, a vacuum of 5 mmHg or less, and a pressure of 5 kg/cm ² . The copper laminate was stuck on the copper laminate and heat-hardened at 170 ° C for 1 hour to form a cured film, thereby preparing a substrate for evaluation.

<Laser processing property>

Using a carbon dioxide gas laser (LC-2K2, manufactured by Hitachi Via Mechanics Co., Ltd.), the cured film of each substrate for evaluation was irradiated with laser light having a wavelength of 9.3 μm to form a through hole on the cured film. The irradiation conditions were such that the opening diameter was 65 μm, the hole was 3.1 mm, the output was 1.5 W, the pulse width was 20 μsec, and the burst mode was two irradiations.

Each substrate for evaluation for such treatment was evaluated by microscopic observation. Specifically, the surface condition of the evaluation substrate was observed with a laser microscope (VK-8500, manufactured by KEYENCE Co., Ltd.), and the diameter of the upper portion and the diameter of the bottom portion after laser processing were measured to evaluate the laser workability. As a result, compared with Comparative Example 1-1 containing no pigment, the case where the diameter of the bottom after the laser processing was large and the amount of the bottom of the through hole was less was set to ◎, and the diameter of the bottom portion after the laser processing was larger. The case was set to ○, and the case where the diameter of the bottom after the laser processing was not changed was set to ×. The results are shown in Table 2. And, FIG. 6(a) shows an embodiment. A photograph of the opening (focus bottom) of 1 to 2, and Fig. 6(b) shows a photograph of the opening (bottom of focus) of Comparative Example 1-1.

As can be seen from the results shown in Table 2, the bottom diameters of Examples 1-1, 1-2, 1-3, 1-4, 1-5, and 1-6 were larger than those of Comparative Example 1-1 containing no pigment. , to confirm the improvement of laser processing. Further, the amount of drilling of the bottom of the through hole of Examples 1-4 was confirmed to be less than that of Comparative Example 1-1. On the other hand, in Comparative Example 1-2, the diameter of the bottom portion was unchanged from Comparative Example 1-1 containing no pigment, and it was not confirmed that the laser workability was improved.

<hiddenness>

For each substrate for evaluation, the discoloration of the copper circuit was visually observed from the top of the cured film, and the concealability of the circuit was evaluated. When the discoloration was not confirmed, it was set to ○, and it was confirmed that Δ was slightly discolored, and it was confirmed that the discoloration was ×. The results are shown in Table 3.

As can be seen from the results shown in Table 3, in Examples 1-1, 1-2, 1-3, 1-4, 1-5, and 1-6, the entire surface of the evaluation substrate was concealed by the cured film. High sex, no discoloration confirmed. On the other hand, in Comparative Examples 1-1 and 1-2, discoloration was confirmed. Further, in Example 1-5 in which the resorcinol type epoxy resin was used, the oxidation of the copper circuit on the entire surface of the evaluation substrate was suppressed, and the effect of lowering the appearance property was confirmed.

<Example 2>

The components shown in the following Table 4 (lower layer) and Table 5 (upper layer) were blended, premixed with a stirrer, and kneaded using a triaxial roller mill to prepare a thermosetting resin composition for the lower layer and the upper layer.

(Examples 2-1 to 2-4, Comparative Examples 2-1 to 2-3)

The layers of the lower layer prepared in Tables 4 and 5 were sequentially coated with a thermosetting resin composition for the upper layer on a polyethylene terephthalate (PET) film having a thickness of 38 μm using an applicator. The dried film of each of the examples and the comparative examples shown in Table 6 was prepared by drying at °C. The film thickness after drying of the lower layer was as shown in Table 4, and the film thickness after drying of the upper layer was 10 μm.

<Iron Oxidation Confirmation>

A glossy surface of a copper foil (GTS-MP-18, manufactured by Furukawa Electronics Co., Ltd.) having a thickness of 18 μm was previously treated with a treating agent (CZ-8100+CL-8300, manufactured by Merck Co., Ltd.), thereby forming a equivalent copper etching amount of 1 μm. The outline. The evaluation shown in Table 6 was dried using a two-chamber vacuum laminator (CVP-300, manufactured by Nichigo Mortor Co., Ltd.) at a lamination temperature of 100 ° C, a vacuum of 5 mmHg or less, and a pressure of 5 kg/cm ² . The film was laminated on the previously treated copper foil, and heat-hardened at 170 ° C for 1 hour to form a cured film, thereby preparing a substrate for evaluation.

The cured film was peeled off from the copper foil of each substrate, and the cured film was visually confirmed. The degree of discoloration after hardening due to oxidation of copper. As a result, the case where the discoloration was not confirmed at all was ◎, the case where the discoloration was hardly confirmed was ○, the case where the slight discoloration was confirmed was Δ, and the case where the discoloration was confirmed was ×. The results are shown in Table 7.

As is apparent from the results shown in Table 7, in Example 2-1, discoloration due to oxidation was hardly confirmed. Further, in Example 2-2, since oxidation was suppressed as compared with Example 2-1, discoloration due to oxidation was not confirmed at all. Even in Example 2-3 in which the lower layer was thin, the oxidation inhibiting effect was obtained as compared with the comparative example, but it was confirmed that there was a slight discoloration due to oxidation. In Examples 2-4 which were thicker in the lower layer, discoloration due to oxidation of copper was not confirmed at all. On the other hand, in Comparative Examples 2-1 to 2-3, discoloration due to oxidation of copper was confirmed.

<Appearance color change confirmation>

Next, a double-sided copper-clad laminate (MCL-E-679FGR, manufactured by Hitachi Chemical Co., Ltd.) of 400 mm × 300 mm × thickness 0.8 mm, which is a conductive layer having a thickness of 10 μm, was used as a circuit substrate by using a treating agent (CZ-8100). +CL-8300, manufactured by Merck Co., Ltd.) Pre-treatment was carried out to form a profile having a copper etching amount of 1 μm. Each of the dried film layers shown in Table 6 was used in a two-chamber vacuum laminator (CVP-300, manufactured by Nichigo Mortor Co., Ltd.) at a lamination temperature of 100 ° C, a vacuum of 5 mmHg or less, and a pressure of 5 kg/cm ² . The cured laminate was formed by heat-hardening at 170 ° C for 1 hour on the copper-clad laminate which was previously treated, to prepare a substrate for evaluation.

For the evaluation substrate, the discoloration of the copper circuit was visually confirmed from the cured film, and the concealability of the circuit was evaluated. When the color change was not confirmed, it was set to ○, and it was confirmed that the case of slight discoloration was Δ, and the case where the discoloration was confirmed was set to ×. The results are shown in Table 8.

As is clear from the results shown in Table 8, in Examples 2-1 to 2-4, discoloration was not confirmed because the oxidation of copper was suppressed. On the other hand, in Comparative Examples 2-1 to 2-3, discoloration was confirmed.

Fig. 1 is a graph showing the difference in absorbance spectra of copper before and after oxidation.

Figure 2 is a UV-vis (ultraviolet. visible) spectrum of Pigment Blue 15:3 used in the examples.

Figure 3 is a UV-vis (ultraviolet. visible) spectrum of Pigment Yellow 147 used in the examples.

Figure 4 is a UV-vis (ultraviolet. visible) spectrum of Pigment Red 177 used in the examples.

Fig. 5 is an IR (infrared absorption) spectrum of Pigment Blue 15:3 and Pigment Yellow 147 used in the examples.

6(a) and 6(b) are photographs showing the opening portions (bottom of focus) of Example 1-2 and Comparative Example 1-1, respectively.

Figure 7 is a UV-vis (ultraviolet. visible) spectrum of Pigment Blue 15:1 used in the examples.

Figure 8 is an IR (infrared absorption) spectrum of Pigment Blue 15:1 used in the examples.

Claims (11)

A thermosetting resin composition which is a thermosetting resin composition comprising a (A) epoxy resin, (B) a colorant, and (C) a curing agent formed on a copper circuit, which is characterized by the above (B) The colorant has a peak of absorbance in one or both of the wavelength range of 350 to 550 nm or 570 to 700 nm, and has an absorber in the oscillation wavelength of the laser used for laser processing. The thermosetting resin composition of claim 1, wherein the laser is selected from the group consisting of a carbon dioxide laser, a UV-YAG laser, and an excimer laser. The thermosetting resin composition of the first aspect of the invention, which further comprises one or two or more kinds of (D) inorganic fillers in an amount of 30 to 80% by mass in terms of solid content, and the (D) inorganic filler The difference between the refractive index of the agent and the refractive index of the resin component is 0.05 or more. A dry film comprising a dried coating film of the thermosetting resin composition according to any one of claims 1 to 3 on the carrier film. A printed wiring board characterized by having a cured film which is a thermosetting resin composition according to any one of claims 1 to 3, which is formed on a substrate on which a circuit pattern is formed, Or a cured film formed of a dry film of a dried coating film of the thermosetting resin composition on the carrier film. A dry film comprising a dry coating film on a carrier film, the dry coating film being laminated to form a battery made of copper The substrate of the road pattern type is characterized in that the dry coating film is a laser processing and copper circuit which is formed by a lower layer for suppressing oxidation of copper covering the circuit pattern and laminated on the lower layer with one or more layers. The hidden upper layer is formed by (a) an epoxy resin and (b) a composition containing a phenol resin. The dried film of claim 6, wherein the epoxy resin of the above (a) contains a resorcinol type epoxy resin. The dry film of claim 6, wherein at least one of the upper layers is made of a thermosetting resin composition containing (A) an epoxy resin, (B) a colorant, and (C) a curing agent. The (B) colorant has a peak of absorbance in one or both of the wavelength range of 350 to 550 nm or 570 to 700 nm, and has an absorber in the oscillation wavelength of the laser used for laser processing. The dry film of claim 8, wherein the foregoing laser is selected from the group consisting of a carbonate laser, a UV-YAG laser, and an excimer laser. The dry film of the eighth aspect of the invention, wherein the thermosetting resin composition further contains one or two or more kinds of (D) inorganic fillers in an amount of 30 to 80% by mass in terms of solid content. D) The difference between the refractive index of the inorganic filler and the refractive index of the resin component is 0.05 or more. A printed wiring board characterized by laminating the above-mentioned dry coating film on a dried film according to any one of claims 6 to 10 on a substrate on which a circuit pattern of copper is formed, via heat Those who have been hardened.