JP2015010231A - Dry film and printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dry film having a resin layer which is excellent in peelability from a carrier film, and suppresses cracking and falling of powder, and a printed wiring board provided with a cured product obtained by curing the dry film.SOLUTION: A dry film has a resin layer containing a thermosetting resin component, a filler, and at least two solvents. At least two solvents have boiling points of 100°C or higher, have boiling points different by 5°C or more from one another, and contain at least one of a thermoplastic polyhydroxypolyether resin having a phenoxy resin, a polyvinyl acetal resin, and a fluorene skeleton, a block copolymer, and rubber-like particles.

Description

  The present invention relates to a dry film and a printed wiring board, and more specifically, a dry film having a resin layer that is excellent in releasability from a carrier film and suppresses cracking and powder falling, and curing obtained by curing the dry film. The present invention relates to a printed wiring board having an object.

  In recent years, as a method for manufacturing a multilayer printed wiring board, a build-up manufacturing technique in which a resin insulating layer and a conductor layer are alternately stacked on a conductor layer of an inner circuit board has attracted attention. For example, a multilayer printed wiring board in which an epoxy resin composition is applied to a circuit-formed inner layer circuit board, heat-cured, a roughened surface is formed on the surface with a roughening agent, and a conductor layer is formed by plating Has been proposed (see Patent Document 1 and Patent Document 2). Also, after laminating an adhesive sheet of an epoxy resin composition on a circuit-formed inner layer circuit board and heat-curing it, a roughening surface is formed on the surface with a roughening agent, and a conductor layer is formed by plating A method for manufacturing a printed wiring board has been proposed (see Patent Document 3).

  An example of a conventional method for forming a multilayer printed wiring board layer structure by a build-up method will be described with reference to FIG. 1. First, an inner layer conductor pattern 3 and a resin insulating layer 4 are formed on both surfaces of an insulating substrate 1 in advance. The outer layer conductor pattern 8 is formed on both surfaces of the laminated substrate X, and an insulating resin composition such as an epoxy resin composition is formed on the outer layer conductor pattern 8 by coating, and is cured by heating to form the resin insulating layer 9. Next, through holes 21 and the like are appropriately provided, a conductor layer is formed on the surface of the resin insulating layer 9 by electroless plating, etc., and then a predetermined circuit pattern is formed on the conductor layer according to a conventional method. A pattern 10 can be formed.

  As one method for forming a resin insulating layer (hereinafter referred to as an interlayer insulating layer) provided between layers in a multilayer printed wiring board, as described in Patent Document 3, a thermosetting resin composition such as an epoxy resin composition is used. A method is used in which a dry film having a resin layer obtained by coating and drying the film is heat-cured after lamination.

JP-A-7-304931 (Claims) JP-A-7-304933 (Claims) JP 2010-1403 A (Claims)

  A liquid epoxy resin is used as one of the thermosetting components blended in the dry film (for example, Patent Document 3). When the liquid epoxy resin is contained, the adhesion of the dry film is excellent, and it does not break or fall off. However, when a liquid epoxy resin is included, there is a problem that when the carrier film is peeled off from the resin layer, the resin layer adheres to the carrier film and part or all of the resin film is peeled off.

  Accordingly, an object of the present invention is to provide a dry film having a resin layer excellent in carrier film peelability and suppressing cracking and powder falling, and a printed wiring board comprising a cured product obtained by curing the dry film. There is to do.

  As a result of intensive studies in view of the above, the present inventors have found that the above problem can be solved by blending two kinds of solvents having boiling points of 100 ° C. or higher and different boiling points, and to complete the present invention. It came.

  That is, the dry film of the present invention is a dry film having a resin layer containing a thermosetting resin component, a filler, and at least two kinds of solvents, and each of the at least two kinds of solvents has a boiling point. The temperature is 100 ° C. or higher and the boiling point differs by 5 ° C. or higher.

  In the dry film of the present invention, the at least two kinds of solvents are preferably at least two kinds selected from the group consisting of N, N-dimethylformamide, toluene, cyclohexanone and aromatic hydrocarbons having 8 or more carbon atoms. .

  In the dry film of the present invention, the filler content is preferably 30 to 80% by weight based on the total amount of the dry film excluding the solvent.

  The dry film of the present invention preferably contains an epoxy compound as the thermosetting resin component, and further contains a curing agent.

  The dry film of the present invention is preferably used for producing a printed wiring board.

  The printed wiring board of the present invention comprises a cured product obtained by curing the resin layer of the dry film.

  According to the present invention, there is provided a dry film having a resin layer excellent in releasability from a carrier film and suppressing cracking and powder falling, and a printed wiring board comprising a cured product obtained by curing the dry film. can do.

It is a fragmentary sectional view which shows schematic structure of the multilayer printed wiring board produced by the conventional buildup method. It is a schematic side view which shows the two test tubes used for the liquid determination of the epoxy resin.

  The dry film of the present invention is a dry film having a resin layer containing a thermosetting resin component, a filler, and at least two kinds of solvents, and each of the at least two kinds of solvents has a boiling point of 100 ° C. The boiling point differs by 5 ° C. or more. The boiling point difference is, for example, 5 ° C. or higher and 130 ° C. or lower.

If only a solvent having a boiling point of less than 100 ° C. is used, the resin layer of the dry film will be dried too much, resulting in poor flexibility, cracking, or powder falling.
On the other hand, when only one type of solvent having a boiling point of 100 ° C. or higher is used, or when two types of solvents having a difference in boiling point of less than 5 ° C. are used, the solvent remains excessively even after drying. Therefore, since the resin layer is also peeled off when the carrier film is peeled off, the peelability is poor. Further, bubbles are easily generated, and it becomes difficult to form a flat resin layer. Moreover, when it dries at high temperature trying to reduce a residual solvent, thermosetting will advance too much in spite of a drying process.
However, a dry film having a resin layer that has excellent peeling properties from a carrier film and suppresses cracking and powder falling by blending two types of solvents having boiling points of 100 ° C. or higher and different boiling points of 5 ° C. or higher. Can be obtained. Hereinafter, each component of the resin layer of the dry film of the present invention will be described.

[Thermosetting resin component]
The resin layer of the dry film of the present invention contains a thermosetting resin component. The thermosetting resin component is a resin having a functional group that can be cured by heat. The thermosetting resin component is not particularly limited, and an epoxy compound, a polyfunctional oxetane compound, a compound having two or more thioether groups in the molecule, that is, an episulfide resin can be used.

  The epoxy compound is a compound having an epoxy group, and any conventionally known one can be used. Examples thereof include a bifunctional epoxy compound having two epoxy groups in the molecule and a polyfunctional epoxy compound having many epoxy groups in the molecule. In addition, a hydrogenated bifunctional epoxy compound may be used.

  Examples of the epoxy compound include bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, and cresol novolak 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, anthracene type epoxy resin, norbornene type epoxy resin, adamantane type epoxy resin, fluorene type epoxy resin, aminophenol type epoxy resin Resin, amino cresol type epoxy resin, alkylphenol type epoxy resin or the like is used. These epoxy resins can be used alone or in combination of two or more.

  The epoxy compound may be a solid epoxy resin, a semi-solid epoxy resin, or a liquid epoxy resin. In this specification, a solid epoxy resin refers to an epoxy resin that is solid at 40 ° C., and a semi-solid epoxy resin refers to an epoxy resin that is solid at 20 ° C. and is liquid at 40 ° C. Means an epoxy resin that is liquid at 20 ° C.

Judgment of liquid state shall be made in accordance with the second “Liquid Confirmation Method” of the Ministerial Ordinance on Dangerous Goods Testing and Properties (Ministry of Local Government Ordinance No. 1 of 1989).
(1) Equipment constant temperature water bath:
A thing equipped with a stirrer, a heater, a thermometer, and an automatic temperature controller (with temperature control at ± 0.1 ° C.) having a depth of 150 mm or more is used.
In the determination of the epoxy resin used in the examples to be described later, a combination of a low temperature thermostatic water bath (model BU300) manufactured by Yamato Scientific Co., Ltd. and a thermostat (model BF500) of a charging type thermostatic apparatus (model BF500) is used. Is put into a low temperature constant temperature water bath (model BU300), the thermomate (model BF500) assembled to this is turned on and set to a set temperature (20 ° C or 40 ° C), and the water temperature is set to a set temperature ± 0.1 ° C. Although fine adjustment was performed with a thermomate (model BF500), any apparatus capable of the same adjustment can be used.

Test tube:
As shown in FIG. 2, the test tube is made of a flat bottom cylindrical transparent glass having an inner diameter of 30 mm and a height of 120 mm, and marked lines 31 and 32 are respectively provided at heights of 55 mm and 85 mm from the tube bottom. The test tube 30a for liquid judgment with the test tube 30a sealed with a rubber plug 33a is the same size as that of the test tube 30a. The rubber plug 33b is similarly provided with a marked line and a hole for inserting and supporting a thermometer in the center. A test tube 30b for temperature measurement in which the mouth of the test tube is sealed and a thermometer 34 is inserted into the rubber plug 33b is used. Hereinafter, a marked line having a height of 55 mm from the tube bottom is referred to as “A line”, and a marked line having a height of 85 mm from the tube bottom is referred to as “B line”.
As the thermometer 34, the one for freezing point measurement (SOP-58 scale range 20-50 ° C) specified in JIS B7410 (1982) "Petroleum test glass thermometer" is used, but the temperature is 0-50 ° C. It is sufficient if the range can be measured.

(2) Test procedure The liquid test tube 30a shown in FIG. 2 (a) and the temperature measurement test shown in FIG. 2 (b) were prepared for 24 hours or more at atmospheric pressure of 20 ± 5 ° C. Insert up to line A in each tube 30b. The two test tubes 30a and 30b are left standing in a low temperature constant temperature water tank so that the line B is below the water surface. The thermometer has its lower end 30 mm below the A line.
The sample temperature is maintained for 10 minutes after the sample temperature reaches the set temperature ± 0.1 ° C. Ten minutes later, the test tube 30a for liquid judgment is taken out of the low-temperature water bath and immediately tilted horizontally on a horizontal test stand, and the time when the tip of the liquid level in the test tube has moved from the A line to the B line is measured with a stopwatch. Measure and record. A sample is determined to be liquid when the measured temperature is 90 seconds or less at a set temperature, and solid when it exceeds 90 seconds.

  As the solid epoxy resin, HP-4700 (naphthalene type epoxy resin) manufactured by DIC, EXA4700 (tetrafunctional naphthalene type epoxy resin) manufactured by DIC, NC-7000 (polyfunctional solid epoxy resin containing naphthalene skeleton) manufactured by Nippon Kayaku Co., Ltd. Naphthalene-type epoxy resins such as EPPN-502H (trisphenol epoxy resin) manufactured by Nippon Kayaku Co., Ltd. Epoxidized products (trisphenol-type epoxy resins) of condensation products of phenols and aromatic aldehydes having a phenolic hydroxyl group; Dicyclopentadiene aralkyl epoxy resin such as Epiklon HP-7200H (dicyclopentadiene skeleton-containing polyfunctional solid epoxy resin) manufactured by Nippon Kayaku Co., Ltd .; biphenyl aralkyl such as NC-3000H (biphenyl skeleton-containing polyfunctional solid epoxy resin) manufactured by Nippon Kayaku Co., Ltd. Type Epoxy Resin; biphenyl / phenol novolak type epoxy resin such as NC-3000L manufactured by Nippon Kayaku; novolak type epoxy resin such as Epicron N660 and Epicron N690 manufactured by DIC, EOCN-104S manufactured by Nippon Kayaku; YX- manufactured by Mitsubishi Chemical Corporation Biphenyl type epoxy resin such as 4000; Phosphorus-containing epoxy resin such as TX0712 manufactured by Nippon Steel & Sumikin Chemical Co .; Tris (2,3-epoxypropyl) isocyanurate such as TEPIC manufactured by Nissan Chemical Industries, Ltd.

  Semi-solid epoxy resins include DIC Corporation Epicron 860, Epicron 900-IM, Epicron EXA-4816, Epicron EXA-4822, Asahi Ciba Araldite AER280, Toto Kasei Epoto YD-134, Japan Epoxy Resin Corporation jER834. , JER872, bisphenol A type epoxy resin such as ELA-134 manufactured by Sumitomo Chemical Co., Ltd .; naphthalene type epoxy resin such as Epicron HP-4032 manufactured by DIC; phenol novolak type epoxy resin such as Epicron N-740 manufactured by DIC It is done.

  Liquid epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, glycidylamine type epoxy resin, aminophenol type epoxy resin And alicyclic epoxy resins.

  Examples of the polyfunctional oxetane compound include bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl] ether, 1,4-bis [(3-methyl -3-Oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) In addition to polyfunctional oxetanes such as methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate and oligomers or copolymers thereof, oxetane alcohol and novolac resin, Poly (p-hydroxystyrene), cardo-type bisphe Lumpur acids, calixarenes, calix resorcin arenes or etherified products such as the resin having a hydroxyl group such as silsesquioxane and the like. In addition, a copolymer of an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate is also included.

  Examples of the episulfide resin include bisphenol A type episulfide resin. In addition, an episulfide resin or the like in which the oxygen atom of the epoxy group of the epoxy resin is replaced with a sulfur atom can be used by using a similar synthesis method.

  The thermosetting resin component is preferably an epoxy compound. Furthermore, since a cured product having a high glass transition temperature (Tg) and excellent crack resistance can be obtained, at least one of a solid epoxy resin and a semi-solid epoxy resin is preferable. The epoxy compound is preferably an aromatic epoxy resin from the viewpoint of preferable physical properties of the cured product. Among these, naphthalene type epoxy compounds and biphenyl type epoxy compounds are more preferable. In the present specification, the aromatic epoxy resin means an epoxy resin having an aromatic ring skeleton in the molecule.

  A thermosetting resin component can be used individually by 1 type or in combination of 2 or more types. The compounding amount of the thermosetting resin component is preferably 10 to 50% by weight, more preferably 20 to 40% by weight, and more preferably 20 to 35% by weight based on the total amount of the resin layer of the dry film excluding the solvent. % Is even more preferred. Further, when a liquid epoxy resin is blended, the glass transition temperature (Tg) of the cured product is lowered and crack resistance may be deteriorated. Therefore, the blending amount of the liquid epoxy resin is 0 per total weight of the thermosetting resin component. It is preferably ˜45% by weight, more preferably 0 to 30% by weight, and particularly preferably 0 to 5% by weight.

[Filler]
The resin layer of the dry film of the present invention contains a filler. By containing the filler, the thermal properties of the dry film can be improved by combining the heat strength with a conductor layer such as copper around the insulating layer. As the filler, all conventionally known inorganic fillers and organic fillers can be used, and the filler is not limited to a specific one. However, the inorganic filler contributes to improvement of properties such as adhesion and hardness by suppressing the curing shrinkage of the coating film. Is preferred. Examples of inorganic fillers include barium sulfate, barium titanate, amorphous silica, crystalline silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, silicon nitride, and aluminum nitride. And extender pigments such as copper, tin, zinc, nickel, silver, palladium, aluminum, iron, cobalt, gold and platinum. Among these inorganic fillers, silica and barium sulfate which are not easily attacked by the roughening liquid are preferable. Particularly, spherical silica is preferable because it has a small specific gravity and can be blended in a high proportion in the composition and is excellent in low thermal expansion. . The average particle size of the filler is preferably 3 μm or less, more preferably 1 μm or less. The average particle size can be determined by a laser diffraction particle size distribution measuring device.

  The blending amount of the filler is preferably 1 to 90% by weight, more preferably 10 to 90% by weight, and 30 to 80% by weight based on the total amount of the resin layer of the dry film excluding the solvent. Is more preferable. When the blending amount of the filler is 1% by weight or more, the thermal expansion can be suppressed and the heat resistance can be improved. On the other hand, when the filler content is 90% by weight or less, the hardness of the cured product is improved and the occurrence of cracks can be suppressed.

[solvent]
The resin layer of the dry film of the present invention contains two types of solvents having boiling points of 100 ° C. or higher and different boiling points of 5 ° C. or higher. The difference in boiling points is preferably 10 ° C. or higher, more preferably 20 ° C. or higher. The solvent is not particularly limited, and a conventionally known solvent having a boiling point of 100 ° C. or higher can be used. In the present invention, when the boiling point of the solvent varies, the boiling point is from the initial boiling point to the end point during distillation.

  Solvents having a boiling point of 100 ° C. or higher include isobutyl alcohol, toluene, methyl isobutyl ketone, n-butanol, butyl acetate, 2-methoxypropanol, isobutyl acetate, tetrachloroethylene, ethylene glycol monomethyl ether, methyl butyl ketone, isopentyl alcohol, ethylene Examples include glycol monoethyl ether, N, N-dimethylformamide (DMF), ethylene glycol monoethyl ether acetate, turpentine oil, cyclohexanone, and ethylene glycol monobutyl ether.

  Further, as a solvent having a boiling point of 100 ° C. or higher, xylene, petroleum naphtha, Maruzen Petrochemical's Swazol 1000 (carbon number 8 to 10: high-boiling aromatic hydrocarbon), Swazol 1500 (high-boiling aromatic hydrocarbon), Solvesso 100 (carbon number 9-10: high-boiling aromatic hydrocarbon) manufactured by Standard Petroleum Osaka Sales Office, Solvesso 150 (carbon number 10-11: high-boiling aromatic hydrocarbon), Solvent # 100, Sankyo Chemical Co., Solvent # 150, Shellzol A100, Shellzol A150 manufactured by Shell Chemicals Japan Co., Ltd., Ipsol No. 100 (mainly composed of aromatic hydrocarbons having 9 carbon atoms), Ipsol No. 150 (aromatic hydrocarbons having 10 carbon atoms) Main component). The high-boiling aromatic hydrocarbon preferably contains 99% by volume or more of an aromatic component. Moreover, it is preferable that each of high-boiling aromatic hydrocarbons is less than 0.01% by volume of benzene, toluene and xylene.

  The resin layer of the dry film of the present invention may contain three or more kinds of solvents having boiling points of 100 ° C. or higher, and in this case, the boiling points of any two kinds of solvents may be different. Among solvents having a boiling point of 100 ° C. or higher, solvents having a boiling point of 100 to 230 ° C. are preferable, and solvents having a boiling point of 100 to 220 ° C. are more preferable. When the boiling point is 230 ° C. or lower, the solvent hardly remains in the resin layer of the dry film after thermosetting or annealing. More preferably, the solvent is toluene, N, N-dimethylformamide, cyclohexanone, petroleum naphtha, or aromatic hydrocarbon having 8 or more carbon atoms.

  The amount of the solvent before drying is preferably 10 to 150 parts by weight, and more preferably 25 to 100 parts by weight with respect to 100 parts by weight of the resin layer of the dry film excluding the solvent. When the blending amount of the solvent is 10 parts by weight or more, the solubility is improved and the amount of the residual solvent is easily adjusted. On the other hand, when it is 150 parts by weight or less, the thickness of the resin layer is easily controlled.

  The amount of the solvent after drying, that is, the ratio of the residual content of the solvent is preferably 0.1 to 4% by weight based on the total amount of the resin layer of the dry film containing the solvent, and is preferably 0.3 to 3% by weight. % Is more preferable.

  The resin layer of the dry film of the present invention may contain a solvent having a boiling point of less than 100 ° C. Solvents having a boiling point of less than 100 ° C. include diethyl ether, carbon disulfide, acetone, chloroform, methanol, n-hexane, ethyl acetate, 1,1,1-trichloroethane, carbon tetrachloride, methyl ethyl ketone, isopropyl alcohol, trichloroethylene, acetic acid. And isopropyl.

(Curing agent)
The resin layer of the dry film of the present invention can contain a curing agent. Examples of the curing agent include phenol resins, polycarboxylic acids and acid anhydrides thereof, cyanate ester resins, and active ester resins. A hardening | curing agent can be used individually by 1 type or in combination of 2 or more types.

  Examples of the phenol resin include phenol novolac resin, alkylphenol volac resin, bisphenol A novolac resin, dicyclopentadiene type phenol resin, Xylok type phenol resin, terpene modified phenol resin, cresol / naphthol resin, polyvinylphenols, phenol / naphthol resin. Conventionally known ones such as an α-naphthol skeleton-containing phenol resin and a triazine-containing cresol novolak resin can be used singly or in combination of two or more.

  The polycarboxylic acid and acid anhydride thereof are compounds having two or more carboxyl groups in one molecule and acid anhydrides thereof, such as a copolymer of (meth) acrylic acid and a copolymer of maleic anhydride. In addition to condensates of dibasic acids, resins having a carboxylic acid end such as a carboxylic acid-terminated imide resin can be mentioned.

  The cyanate ester resin is a compound having two or more cyanate ester groups (—OCN) in one molecule. Any conventionally known cyanate ester resins can be used. Examples of the cyanate ester resin include phenol novolac type cyanate ester resin, alkylphenol novolak type cyanate ester resin, dicyclopentadiene type cyanate ester resin, bisphenol A type cyanate ester resin, bisphenol F type cyanate ester resin, and bisphenol S type cyanate ester resin. Is mentioned. Further, it may be a prepolymer partially triazine.

  The active ester resin is a resin having two or more active ester groups in one molecule. The active ester resin can generally be obtained by a condensation reaction between a carboxylic acid compound and a hydroxy compound. Among these, an active ester compound obtained by using a phenol compound or a naphthol compound as the hydroxy compound is preferable. Examples of phenol compounds or naphthol compounds include hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol S, phenolphthaline, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol , Dicyclopentadienyl diphenol, phenol novolac and the like.

  Moreover, you may use an alicyclic olefin polymer as a hardening | curing agent. Specific examples of the method for producing an alicyclic olefin polymer include (1) an alicyclic olefin having a carboxyl group and / or a carboxylic acid anhydride group (hereinafter referred to as “carboxyl group etc.”) as necessary. (2) The aromatic ring portion of the (co) polymer obtained by polymerizing an aromatic olefin having a carboxyl group or the like with another monomer as necessary. (3) a method of copolymerizing an alicyclic olefin having no carboxyl group and a monomer having a carboxyl group, (4) an aromatic olefin having no carboxyl group, and a carboxyl group A method of hydrogenating an aromatic ring portion of a copolymer obtained by copolymerizing with a monomer having, for example, (5) an alicyclic olefin polymer having no carboxyl group or the like having a carboxyl group or the like. Or a carboxylic acid ester group of an alicyclic olefin polymer having a carboxylic acid ester group obtained as described in (1) to (5) above, for example, The method etc. which convert to a carboxyl group by decomposition | disassembly etc. are mentioned.

  Among the curing agents, phenol resin, cyanate ester resin, active ester resin, and alicyclic olefin polymer are preferable.

  In the curing agent, the ratio of the functional group capable of thermosetting reaction, such as the epoxy group of the thermosetting resin component, to the functional group in the curing agent that reacts with the functional group is the functional group of the curing agent / thermosetting. It is preferable to blend in such a ratio that the functional group capable of reacting (equivalent ratio) = 0.2-2. By setting the functional group of the curing agent / functional group capable of thermosetting reaction (equivalent ratio) within the above range, roughening of the film surface in the desmear process can be prevented. More preferably, the functional group of the curing agent / functional group capable of thermosetting reaction (equivalent ratio) = 0.2 to 1.5, and more preferably the functional group of the curing agent / functional group capable of thermosetting reaction ( Equivalent ratio) = 0.3 to 1.0.

(Thermoplastic resin)
The resin layer of the dry film of the present invention can further contain a thermoplastic resin in order to improve the mechanical strength of the resulting cured film. The thermoplastic resin is preferably soluble in a solvent. When it is soluble in the solvent, the flexibility of the dry film is improved, and the generation of cracks and powder falling can be suppressed.
As the thermoplastic resin, use is made of thermoplastic polyhydroxy polyether resin, phenoxy resin that is a condensate of epichlorohydrin and various bifunctional phenolic compounds, or hydroxyl group of hydroxy ether part present in the skeleton of various acid anhydrides and acid chlorides. And esterified phenoxy resin, polyvinyl acetal resin, polyamide resin, polyamideimide resin, block copolymer and the like. A thermoplastic resin can be used individually by 1 type or in combination of 2 or more types.

  The polyvinyl acetal resin is obtained, for example, by acetalizing a polyvinyl alcohol resin with an aldehyde. The aldehyde is not particularly limited, and examples thereof include formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde and the like.

Specific examples of the phenoxy resin include FX280 and FX293 manufactured by Tohto Kasei Co., Ltd., YX8100, YL6954 and YL6974 manufactured by Mitsubishi Chemical Corporation.
Specific examples of the polyvinyl acetal resin include SLEKS KS series manufactured by Sekisui Chemical Co., Ltd., KS5000 series manufactured by Hitachi Chemical Co., Ltd. as the polyamide resin, BP series manufactured by Nippon Kayaku Co., Ltd., and KS9000 manufactured by Hitachi Chemical Co., Ltd. as the polyamideimide resin. Series etc. are mentioned.

When a thermoplastic polyhydroxy polyether resin has a fluorene skeleton, it has a high glass transition point and excellent heat resistance. Therefore, it maintains a low coefficient of thermal expansion due to a semi-solid or solid epoxy resin and maintains its glass transition point. The resulting cured film has a low thermal expansion coefficient and a high glass transition point in a well-balanced manner.
In addition, since the thermoplastic polyhydroxy polyether resin has a hydroxyl group, it exhibits good adhesion to the substrate and the conductor, and the cured film obtained is not easily affected by the roughening agent, but the aqueous solution is roughened. Since the liquid easily penetrates into the interface between the cured film and the filler, the roughening treatment makes it easy for the filler on the surface of the cured film to come off, and it becomes easy to form a good roughened surface.

  A block copolymer may be used as the thermoplastic resin. The block copolymer is a copolymer having a molecular structure in which two or more kinds of polymers having different properties are connected by a covalent bond to form a long chain.

The block copolymer is preferably an ABA type or ABA 'type block copolymer. Of the ABA type and ABA type block copolymers, the central B is a soft block and has a low glass transition temperature (Tg), preferably less than 0 ° C. Alternatively, it is preferable that A ′ is a hard block and has a high glass transition temperature (Tg), preferably composed of polymer units of 0 ° C. or higher. The glass transition temperature (Tg) is measured by differential scanning calorimetry (DSC).
Further, among the ABA type and ABA type block copolymers, A or A ′ is composed of polymer units having a Tg of 50 ° C. or higher, and B has a glass transition temperature (Tg) of −20. More preferred is a block copolymer composed of polymer units having a temperature of 0 ° C. or lower.
Of the ABA type and ABA type block copolymers, those in which A or A 'is highly compatible with the thermosetting resin component are preferred, and B is the thermosetting type. Those having low compatibility with the resin component are preferred. Thus, it is considered that a specific structure in the matrix can be easily shown by using a block copolymer in which the blocks at both ends are compatible with the matrix and the central block is incompatible with the matrix.

  Among the thermoplastic resins, phenoxy resin, polyvinyl acetal resin, thermoplastic polyhydroxy polyether resin having a fluorene skeleton, and a block copolymer are preferable.

  The blending amount of the thermoplastic resin is 1 to 20 parts by weight, preferably 1 to 10 parts by weight with respect to 100 parts by weight of the thermosetting resin component. When the blending amount of the thermoplastic resin is out of the above range, it becomes difficult to obtain a uniform roughened surface state.

(Rubbery particles)
Furthermore, the resin layer of the dry film of the present invention can contain rubber-like particles as necessary. Examples of such rubber-like particles include polybutadiene rubber, polyisopropylene rubber, urethane-modified polybutadiene rubber, epoxy-modified polybutadiene rubber, acrylonitrile-modified polybutadiene rubber, carboxyl group-modified polybutadiene rubber, acrylonitrile butadiene rubber modified with a carboxyl group or a hydroxyl group, and These crosslinked rubber particles, core-shell type rubber particles, and the like can be mentioned, and one kind can be used alone or two or more kinds can be used in combination. These rubber-like particles are added to improve the flexibility of the resulting cured film, improve crack resistance, enable surface roughening treatment with an oxidizing agent, and improve adhesion strength with copper foil, etc. Is done.

  The average particle size of the rubber-like particles is preferably in the range of 0.005 to 1 μm, and more preferably in the range of 0.2 to 1 μm. The average particle diameter of the rubber-like particles in the present invention can be measured using a dynamic light scattering method. For example, rubber-like particles are uniformly dispersed in an appropriate organic solvent by ultrasonic waves, etc., and using FPRA-1000 (manufactured by Otsuka Electronics Co., Ltd.), the particle size distribution of the rubber-like particles is created on a weight basis, and the median diameter is determined. The average particle size can be measured.

  The compounding amount of the rubber-like particles is preferably 0.5 to 10 parts by weight and more preferably 1 to 5 parts by weight with respect to 100 parts by weight of the thermosetting resin component. In the case of 0.5 parts by weight or more, crack resistance is obtained, and the adhesion strength with a conductor pattern or the like can be improved. In the case of 10 parts by weight or less, the coefficient of thermal expansion (CTE) decreases, the glass transition temperature (Tg) increases, and the curing characteristics are improved.

(Curing accelerator)
The resin layer of the dry film of the present invention can contain a curing accelerator. The curing accelerator is for accelerating the thermosetting reaction, and is used for further improving properties such as adhesion, chemical resistance, and heat resistance. Specific examples of such curing accelerators include imidazole and derivatives thereof; guanamines such as acetoguanamine and benzoguanamine; diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, Polyamines such as melamine and polybasic hydrazides; organic acid salts and / or epoxy adducts thereof; amine complexes of boron trifluoride; ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4- Triazine derivatives such as diamino-6-xylyl-S-triazine; trimethylamine, triethanolamine, N, N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa (N-methyl) Amines such as lamin, 2,4,6-tris (dimethylaminophenol), tetramethylguanidine, m-aminophenol; polyphenols such as polyvinylphenol, polyvinylphenol bromide, phenol novolac, alkylphenol novolac; tributylphosphine, tri Organic phosphines such as phenylphosphine and tris-2-cyanoethylphosphine; phosphonium salts such as tri-n-butyl (2,5-dihydroxyphenyl) phosphonium bromide and hexadecyltributylphosphonium chloride; benzyltrimethylammonium chloride and phenyltributylammonium chloride Quaternary ammonium salts such as polybasic acid anhydrides; diphenyliodonium tetrafluoroboroate, triphenyl Photocationic polymerization catalyst such as sulfonium hexafluoroantimonate and 2,4,6-triphenylthiopyrylium hexafluorophosphate; styrene-maleic anhydride resin; equimolar reaction product of phenyl isocyanate and dimethylamine, tolylene diisocyanate, Conventionally known curing accelerators such as an equimolar reaction product of an organic polyisocyanate such as isophorone diisocyanate and dimethylamine, and a metal catalyst can be used. Among the curing accelerators, phosphonium salts are preferred because BHAST resistance is obtained.

A hardening accelerator can be used individually by 1 type or in mixture of 2 or more types. The use of a curing accelerator is not essential, but particularly when it is desired to accelerate curing, it can be used preferably in the range of 0.01 to 5 parts by weight with respect to 100 parts by weight of the thermosetting resin component.
In the case of a metal catalyst, 10 to 550 ppm is preferable in terms of metal with respect to 100 parts by weight of the thermosetting resin component, and 25 to 200 ppm is preferable.

(Other ingredients)
If necessary, the resin layer of the dry film of the present invention may be a conventionally known colorant such as phthalocyanine blue, phthalocyanine green, iodin green, disazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, Conventionally known thickeners such as asbestos, olben, benton, fine silica, etc., defoamers and / or leveling agents such as silicones, fluorines and polymers, thiazoles, triazoles, silane coupling agents, etc. Conventionally known additives such as adhesion imparting agents, flame retardants, titanates and aluminum can be used.

  The dry film of the present invention is formed by applying a thermosetting resin composition for forming a resin layer on a carrier film, drying, laminating a protective film as necessary, and forming a dry coating film. Can be manufactured.

  As a material of the carrier film, polyethylene terephthalate (PET) can be preferably used, and other polyesters such as polyethylene naphthalate, polypropylene (PP), and polycarbonate can be used. The thickness of the carrier film is preferably 8 to 60 μm.

  As the material of the protective film, the same material as that used for the carrier film can be used, and preferably PET or PP. The thickness of the protective film is preferably 5 to 50 μm.

  Here, as a method for applying the thermosetting resin composition, a known method such as a screen printing method can be used. Moreover, as a volatile drying method, the well-known method using a hot-air circulation type drying furnace etc. can be used.

  Moreover, the printed wiring board of this invention comprises the hardened | cured material obtained by hardening | curing the dry film of this invention. Although the manufacturing method is demonstrated below, it is not limited to this.

The dry film of the present invention is obtained by applying a thermosetting composition on a supporting base film and drying the solvent. Here, the thermosetting composition contains a thermosetting resin component, a filler, and at least two kinds of solvents, and each of the at least two kinds of solvents has a boiling point of 100 ° C. or higher. Yes, and the boiling point differs by 5 ° C. or more.
Examples of the supporting base film include polyolefins such as polyethylene and polyvinyl chloride, polyesters such as polyethylene terephthalate, polycarbonates and polyimides, and metal foils such as release paper, copper foil, and aluminum foil. Note that the support base film may be subjected to a release treatment in addition to the mud treatment and the corona treatment.

  The dry film of the present invention may be integrally laminated by heating to an inner layer circuit board on which a circuit is formed, and then cured in an oven or cured by a hot plate press.

  Among the above steps, the method of laminating or hot plate pressing is preferable because the fine unevenness caused by the inner layer circuit is eliminated when heated and melted and is cured as it is, so that a multilayer plate having a flat surface state can be finally obtained. Moreover, when laminating or hot plate pressing the base material on which the inner layer circuit is formed and the dry film of the present invention, the copper foil or the base material on which the circuit is formed can be simultaneously laminated.

A hole is made in the substrate thus obtained with a semiconductor laser such as a CO ₂ laser or a UV-YAG laser or a drill. The hole is a through hole (through hole) that is intended to connect the front and back of the substrate, but it is also a partial hole (conformal via) that is intended to connect the inner layer circuit and the circuit on the surface of the interlayer insulating layer. either will do.

  After drilling, in order to remove the residue (smear) present on the inner wall and bottom of the hole and to develop an anchor effect with the conductor layer (the metal plating layer to be formed thereafter), a rough surface with fine irregularities For the purpose of forming a chemical surface, a commercially available desmear liquid (roughening agent) or a roughening liquid containing an oxidizing agent such as permanganate, dichromate, ozone, hydrogen peroxide / sulfuric acid, nitric acid, etc. Do it at the same time.

  Next, a circuit is formed by a subtractive method, a semi-additive method, or the like after forming a hole from which a residue has been removed with a desmear liquid or a film surface having a fine uneven rough surface. In either method, after electroless plating or electrolytic plating, or after both plating, a heat treatment called annealing at about 80 to 180 ° C. for about 10 to 60 minutes for the purpose of removing stress from the metal and improving the strength. May be applied.

  As metal plating used here, there is no restriction | limiting in particular, such as copper, tin, solder, nickel, etc., It can also be used in multiple combination. Further, instead of the plating used here, metal sputtering or the like can be used instead.

  The dry film of this invention can be used suitably for manufacture of a printed wiring board. In particular, it can be suitably used for forming an insulating layer of a printed wiring board such as an interlayer insulating layer or a solder resist layer. You may form a wiring board by bonding a wiring together using the dry film of this invention. It can also be suitably used as a sealing resin for semiconductor chips.

  EXAMPLES Hereinafter, although an Example, a comparative example, and a test example of this invention are shown and this invention is demonstrated concretely, it cannot be overemphasized that this invention is not what is limited to the following Example. In the following, “parts” and “%” are all based on weight unless otherwise specified.

(Examples 1-19 and Comparative Examples 1-3)
The thermosetting resin composition obtained by blending each component in the formulations shown in Tables 1 to 4 below, kneading and dispersing, and adjusting the viscosity to 0.5 to 20 dPa · s (rotary viscometer 5 rpm, 25 ° C.). Each was coated on a carrier film (PET film; Lumirror 38R75 manufactured by Toray Industries, Inc .: 38 μm thick) using a bar coater so that the film thickness of the dry film became 40 μm after drying. Then, it dried at the time and temperature shown to the following Tables 5-8, the protective film was laminated | stacked, and the dry film was obtained. The alicyclic olefin polymers A1 and A2 contained in the thermosetting resin composition of Example 19 were produced as follows.

(Production Example 1 of Alicyclic Olefin Polymer)
Tetracyclo ^{[9.2.1.0 2,10.} 0 ^3,8 ] tetradeca-3,5,7,12-tetraene (methanotetrahydrofluorene, hereinafter abbreviated as “MTF”) 70 mole parts, bicyclo [2.2.1] hept-2-ene-5 , 6-dicarboxylic anhydride (hereinafter abbreviated as “NDCA”) 30 mol part, 1-hexene 0.9 mol part, anisole 590 mol part and 4-acetoxybenzylidene (dichloro) (4 5-Dibromo-1,3-dimesityl-4-imidazoline-2-ylidene) (tricyclohexylphosphine) ruthenium (manufactured by Wako Pure Chemical Industries, Ltd.) in an amount of 0.015 mol in a nitrogen-substituted pressure glass reactor and stirred. The polymer was subjected to a polymerization reaction at 80 ° C. for 1 hour to obtain a ring-opened polymer solution. Next, the solution of the obtained ring-opening polymer was charged into an autoclave equipped with a stirrer purged with nitrogen, and the mixture was stirred at 150 ° C. and a hydrogen pressure of 7 MPa for 5 hours to carry out a hydrogenation reaction, whereby a high molecular weight alicyclic olefin polymer was obtained. Solution was obtained. The obtained alicyclic olefin polymer had a weight average molecular weight of 50,000, a number average molecular weight of 26,000, and a molecular weight distribution of 1.9. The hydrogenation rate was 97%, and the content of repeating units having a carboxylic anhydride group was 30 mol%. The solid content concentration of the alicyclic olefin polymer solution was 40%. Let the obtained alicyclic olefin polymer be alicyclic olefin polymer A1.

(Production Example 2 of Alicyclic Olefin Polymer)
MTF 70 mol part, NDCA 30 mol part, 1-hexene 6 mol part, anisole 590 mol part and 4-acetoxybenzylidene (dichloro) (4,5-dibromo-1,3-dimesityl-4-imidazoline) as ruthenium-based polymerization catalyst 2-ylidene) (tricyclohexylphosphine) ruthenium (manufactured by Wako Pure Chemical Industries, Ltd.) in an amount of 0.015 mol was charged in a pressure-resistant glass reactor substituted with nitrogen, and the polymerization reaction was carried out at 80 ° C. for 1 hour with stirring. A solution of a ring polymer was obtained. Next, the nitrogen-substituted autoclave equipped with a stirrer was charged with the obtained ring-opening polymer solution, and the mixture was stirred at 150 ° C. and a hydrogen pressure of 7 MPa for 5 hours to conduct a hydrogenation reaction. A low molecular weight alicyclic olefin polymer Solution was obtained. The resulting low molecular weight alicyclic olefin polymer had a weight average molecular weight of 10,000, a number average molecular weight of 5,000, and a molecular weight distribution of 2. The hydrogenation rate was 97%, and the content of repeating units having a carboxylic anhydride group was 30 mol%. Anisole was distilled off from the solution under reduced pressure to make the solid concentration 60%. Let the obtained alicyclic olefin polymer be alicyclic olefin polymer A2.

＊１：ビスフェノールＡ型エポキシ樹脂（三菱化学社製；エポキシ当量１８４〜１９４ｇ／ｅｑ；液状）
＊２：ビスフェノールＦ型エポキシ樹脂（三菱化学社製；エポキシ当量１６０〜１７５ｇ／ｅｑ；液状）
＊３：ビスフェノールＡＦ型エポキシ樹脂（三菱化学社製；エポキシ当量２４３ｇ／ｅｑ；結晶性液状）
＊４：ナフタレン型エポキシ樹脂（ＤＩＣ社製；エポキシ当量１６０〜１７０ｇ／ｅｑ；軟化点８５〜９５℃）
＊５：ビフェニル／フェノールノボラック型エポキシ樹脂（日本化薬社製；エポキシ当量２７２ｇ／ｅｑ；軟化点５２℃）
＊６：テトラメチルビフェニル型エポキシ樹脂（三菱化学社製：エポキシ当量１８０〜１９２ｇ／ｅｑ；軟化点１０５℃）
＊７：リン含有エポキシ樹脂（新日鉄住金化学社製；エポキシ当量３５５ｇ／ｅｑ；リン含有率２．６％）
＊８：ナフタレン型エポキシ樹脂（ＤＩＣ社製；エポキシ当量１４５〜１５７ｇ／ｅｑ；半固形）
＊９：フェノールノボラック樹脂（明和化成社製；水酸基当量１０４〜１０８ｇ／ｅｑ；軟化点８２〜８６℃）
＊１０：α−ナフトール骨格含有フェノール樹脂（ＤＩＣ社製；水酸基当量１５０ｇ／ｅｑ、軟化点１１０〜１４０℃）
＊１１：トリアジン含有クレゾールノボラック樹脂（ＤＩＣ社製；水酸基当量１５１ｇ／ｅｑ；窒素含有量１８％）
＊１２：活性エステル化合物（ＤＩＣ社製；活性エステル当量２２３ｇ／ｅｑ）
＊１３：ビスフェノールＡジシアネート（ロンザジャパン社製；シアネート当量２３２ｇ／ｅｑ）
＊１４：フェノールノボラック型多官能シアネートエステル（ロンザジャパン社製；シアネート当量１２４ｇ／ｅｑ）
＊１５：フェノキシ樹脂（三菱化学社製；ガラス転移温度１３０℃）
＊１６：フルオレン＋テトラメチルビフェニル骨格含有フェノキシ樹脂（東都化成工業社製；ガラス転移温度１６３℃）
＊１７：ポリビニルアセトアセタール（積水化学社製；ガラス転移温度１０７℃）
＊１８：コアシェルゴム粒子（アイカ工業社製）
＊１９：フェノール性水酸基を有するリン化合物（三光社製）
＊２０：球状シリカ（アドマテックス社製；平均粒径０．５μｍ）
＊２１：硫酸バリウム（堺化学工業社製；平均粒径０．３μｍ）
＊２２：２−エチル−４−メチルイミダゾール（四国化成工業社製）
＊２３：イミダゾール化合物とエポキシ樹脂のアダクト体（三菱化学社製）
＊２４：ホスホニウム塩（北興産業社製）
＊２５：４−アミノピリジン（広栄化学工業社製）
＊２６：ナフテン酸亜鉛（ＩＩ）ミネラルスピリット（和光純薬工業社製；亜鉛含有量８％）
＊２７：トルエン（沸点１１０℃）
＊２８：２−メトキシプロパノール（沸点１１８℃）
＊２９：シクロヘキサノン（沸点１５０℃）
＊３０：ＤＭＦ（Ｎ，Ｎ−ジメチルホルムアミド；沸点１５３℃）
＊３１：イプゾール１５０（沸点１８４〜２０５℃）
＊３２：ＭＥＫ（メチルエチルケトン；沸点７９．５℃）
＊３３：ヘキサン（沸点６９℃）
＊３４：ジシクロペンタジエン型エポキシ樹脂（ＤＩＣ社製；エポキシ当量２５４〜２６４ｇ／ｅｑ；軟化点５６〜６６℃）
＊３５： フルオレン系エポキシ樹脂（大阪ガスケミカル社製；エポキシ当量３１１ｇ／ｅｑ；軟化点１４０℃）
＊３６：ジシクロペンタジエン型フェノール樹脂（群栄化学工業社製；水酸基当量１６４〜１６７ｇ／ｅｑ；軟化点８５〜８９℃）
＊３７：フルオレン系フェノール樹脂（大阪ガスケミカル社製；水酸基当量１９０ｇ／ｅｑ；軟化点１４２℃）
＊３８：アニソール（キシダ化学社製；沸点１５６℃）

* 1: Bisphenol A type epoxy resin (Mitsubishi Chemical Corporation; epoxy equivalent: 184 to 194 g / eq; liquid)
* 2: Bisphenol F type epoxy resin (Mitsubishi Chemical Corporation; epoxy equivalent 160-175 g / eq; liquid)
* 3: Bisphenol AF type epoxy resin (Mitsubishi Chemical Corporation; epoxy equivalent 243 g / eq; crystalline liquid)
* 4: Naphthalene type epoxy resin (manufactured by DIC; epoxy equivalent 160-170 g / eq; softening point 85-95 ° C.)
* 5: Biphenyl / phenol novolac type epoxy resin (manufactured by Nippon Kayaku Co., Ltd .; epoxy equivalent 272 g / eq; softening point 52 ° C.)
* 6: Tetramethylbiphenyl type epoxy resin (Mitsubishi Chemical Corporation: epoxy equivalent 180-192 g / eq; softening point 105 ° C.)
* 7: Phosphorus-containing epoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd .; epoxy equivalent 355 g / eq; phosphorus content 2.6%)
* 8: Naphthalene type epoxy resin (manufactured by DIC; epoxy equivalent: 145 to 157 g / eq; semi-solid)
* 9: Phenol novolac resin (Maywa Kasei Co., Ltd .; hydroxyl group equivalent: 104 to 108 g / eq; softening point: 82 to 86 ° C.)
* 10: α-naphthol skeleton-containing phenol resin (manufactured by DIC; hydroxyl group equivalent 150 g / eq, softening point 110 to 140 ° C.)
* 11: Triazine-containing cresol novolac resin (manufactured by DIC; hydroxyl group equivalent 151 g / eq; nitrogen content 18%)
* 12: Active ester compound (manufactured by DIC; active ester equivalent: 223 g / eq)
* 13: Bisphenol A dicyanate (Lonza Japan, Inc .; cyanate equivalent 232 g / eq)
* 14: Phenol novolac type polyfunctional cyanate ester (Lonza Japan, Inc .; cyanate equivalent 124 g / eq)
* 15: Phenoxy resin (Mitsubishi Chemical Corporation; glass transition temperature 130 ° C)
* 16: Fluorene + tetramethylbiphenyl skeleton-containing phenoxy resin (manufactured by Toto Kasei Kogyo Co., Ltd .; glass transition temperature 163 ° C)
* 17: Polyvinyl acetoacetal (manufactured by Sekisui Chemical; glass transition temperature 107 ° C.)
* 18: Core shell rubber particles (Aika Industry Co., Ltd.)
* 19: Phosphorus compound having a phenolic hydroxyl group (manufactured by Sanko)
* 20: Spherical silica (manufactured by Admatechs; average particle size 0.5 μm)
* 21: Barium sulfate (manufactured by Sakai Chemical Industry Co., Ltd .; average particle size 0.3 μm)
* 22: 2-ethyl-4-methylimidazole (manufactured by Shikoku Chemicals)
* 23: Adduct body of imidazole compound and epoxy resin (Mitsubishi Chemical Corporation)
* 24: Phosphonium salt (made by Hokuko Sangyo Co., Ltd.)
* 25: 4-aminopyridine (manufactured by Guangei Chemical Industry Co., Ltd.)
* 26: Zinc naphthenate (II) mineral spirit (Wako Pure Chemical Industries, Ltd .; zinc content 8%)
* 27: Toluene (boiling point 110 ° C)
* 28: 2-methoxypropanol (boiling point 118 ° C.)
* 29: Cyclohexanone (boiling point 150 ° C)
* 30: DMF (N, N-dimethylformamide; boiling point 153 ° C.)
* 31: Ipsol 150 (boiling point 184-205 ° C)
* 32: MEK (methyl ethyl ketone; boiling point 79.5 ° C.)
* 33: Hexane (boiling point 69 ° C)
* 34: Dicyclopentadiene type epoxy resin (manufactured by DIC; epoxy equivalent: 254 to 264 g / eq; softening point: 56 to 66 ° C.)
* 35: Fluorene epoxy resin (Osaka Gas Chemical Co., Ltd .; epoxy equivalent 311 g / eq; softening point 140 ° C.)
* 36: Dicyclopentadiene type phenol resin (manufactured by Gunei Chemical Industry Co., Ltd .; hydroxyl group equivalent: 164 to 167 g / eq; softening point: 85 to 89 ° C.)
* 37: Fluorene-based phenol resin (manufactured by Osaka Gas Chemical Company; hydroxyl group equivalent 190 g / eq; softening point 142 ° C.)
* 38: Anisole (Kishida Chemical Co., Ltd., boiling point 156 ° C.)

   The dry film of Examples 1-19 and Comparative Examples 1-3 was evaluated with the evaluation method shown below. The evaluation results are shown in Tables 5-8.

<Measurement of residual content (%) of organic solvent in dry film>
After peeling the carrier film and the protective film from the dry film of each Example and Comparative Example, about 1.2 g of the resin layer was collected, and the mass of the collected resin layer was accurately weighed in a container with a sealed stopper ( W). One drop of ethyl 3-ethoxypropionate was added to this container as an internal standard substance with a pipette, and the mass (We) was accurately weighed. Thereafter, 5 ml of acetone was added with a whole pipette and sealed, and the collected resin layer was dissolved by shaking the container sufficiently. Next, this liquid is filtered with a filter having an opening of 0.5 μm, and the composition of the filtrate is analyzed by gas chromatography (TRACEGULTRA manufactured by Thermo Fisher Scientific), and an organic solvent for 1 g of the internal standard substance is obtained from a separately prepared calibration curve. Was determined (Ws). From these, the residual content of the organic solvent was calculated according to the following formula.
Residual content of organic solvent (% by mass) = (We × Ws / W) × 100

  The measurement conditions in gas chromatography are as follows. Column: Agilent Technologies capillary column DB-1MS (30 m × 0.25 mm), detector: MS (ITQ900), carrier gas: helium, injector temperature: 300 ° C., detector temperature: 230 ° C., column temperature condition: initial temperature 50 ° C., Hold the sample at 50 ° C. for 2 minutes after sample injection, raise the temperature to 300 ° C. at 10 ° C./minute, hold for 10 minutes after reaching 300 ° C.

<Dry film hardness (bending test)>
In accordance with JISK5600-5-1 (ISO 1519), by using a cylindrical mandrel bending tester manufactured by BYK-Gardner, the minimum of mandrel at which the dry film of each example and comparative example begins to crack and peel from the carrier film From the diameter, the hardness of the dry film was evaluated. The evaluation criteria are as follows. When the hardness of the dry film is good, the resin layer has high flexibility and can suppress cracking and powder falling.
◯: There was no occurrence of cracking of the resin layer and peeling of the carrier film in the range of more than φ2 mm and less than 5 mm. There was no powder fall of the resin layer. Further, even with a diameter of 2 mm or less, there was no occurrence of cracking of the resin layer, powder falling, and peeling of the carrier film.
Δ: In the range of more than φ2 mm and less than 5 mm, cracking of the resin layer, powder falling, and peeling of the carrier film occurred.
X: Cracking of resin layer, powder falling, and peeling of carrier film occurred at a diameter of φ5 mm or more.

<Bubble residue>
After peeling off the protective film from the dry film of each Example and Comparative Example, a batch type vacuum pressure laminator MVLP-500 (manufactured by Meiki Co., Ltd.) was used, and the copper conductor thickness was 35 μm and L (line: wiring width) / S (space: interval width) = 100/100 μm was laminated on a comb tooth pattern. Heat lamination was performed under conditions of 5 kgf / cm ² , 180 ° C., 1 minute, and 1 Torr, and then leveling was performed using a hot plate press under the conditions of 10 kgf / cm ² , 180 ° C., and 1 minute. After laminating, 20 places were checked to see if air entered the boundary between the line and the space and holes were generated in the resin layer. The evaluation criteria are as follows. When the resin layer is sticky, that is, when the following carrier film is poorly peelable, air bubbles enter between the resin layer and the comb pattern, and voids increase. In that case, cracks are likely to occur.
○: No void was confirmed. △: One to four voids were confirmed. ×: Five or more voids were confirmed.

<Peelability of carrier film>
After laminating the dry film of each example and comparative example under the same conditions as the above-mentioned test for residual bubbles, the carrier film is peeled off, and it is visually determined whether the resin composition derived from the resin layer is attached to the carrier film. did. The evaluation criteria are as follows.
○: No resin composition adhered to the carrier film Δ: Some resin composition adhered to the carrier film ×: Many resin compositions adhered to the carrier film

<Glass transition temperature (Tg) and coefficient of thermal expansion (CTE (α1))>
Each resin composition of the above-mentioned examples and comparative examples was laminated with a dry film on the glossy surface side (copper foil) of GTS-MP foil (manufactured by Furukawa Circuit Foil Co., Ltd.), and 180 ° C. in a hot air circulation drying furnace. The resin layer was cured for 60 minutes. Then, after peeling hardened | cured material from copper foil, the sample was cut out to the measurement size (size of 3 mm x 10 mm), and it used for TMA6100 by Seiko Instruments Inc. TMA measurement was performed by raising the temperature of the sample from room temperature to 250 ° C. at a rate of temperature increase of 10 ° C./min. The glass transition temperature (Tg) and the coefficient of thermal expansion (CTE (α1)) in the region below Tg were measured. It was measured.

<Solder heat resistance>
The dry film of each example and comparative example was placed on copper of a copper clad laminate using a batch type vacuum press laminator MVLP-500 (manufactured by Meiki Co., Ltd.), 5 kgf / cm ² , 180 ° C., 1 minute, 1 Torr. And then leveling with a hot plate press at 10 kgf / cm ² , 180 ° C. for 1 minute. Thereafter, the carrier film was peeled off, and heated at 180 ° C. for 60 minutes in a hot air circulation drying oven to cure the resin layer, thereby obtaining a test substrate. The obtained test substrate was immersed in a 260 ° C. solder bath 5 times for 10 seconds so that the cured film of the resin layer was in contact with the solder, and then allowed to cool to room temperature. The obtained test substrate was observed visually and with an optical microscope, and the degree of swelling and peeling of the cured film of the resin layer was confirmed. When the solubility of the thermoplastic resin in the solvent is poor, the cured film swells and peels off.
○: No swelling or peeling of the cured film of the resin layer ×: Swelling or peeling of the cured film of the resin layer occurs

<Cooling cycle (suppression of cracks)>
The dry film thickness (resin thickness 40 μm) of each example and comparative example was set to 5 kgf / cm ² on the copper of the copper-clad laminate using a batch type vacuum pressure laminator MVLP-500 (manufactured by Meiki Co., Ltd.), 120 Lamination was performed at 1 ° C. for 1 minute at a temperature. Thereafter, the carrier film was peeled off, and heated at 180 ° C. for 30 minutes in a hot air circulating drying furnace to cure the resin layer. Thereafter, vias were formed using a CO ₂ laser processing machine (manufactured by Hitachi Via Mechanics) so that the top diameter was 65 μm and the bottom diameter was 50 μm.
Next, processing is performed in the order of commercially available wet permanganate desmear (manufactured by ATOTECH), electroless copper plating (Sulcup PEA, manufactured by Uemura Kogyo Co., Ltd.), and electrolytic copper plating treatment, and a copper thickness of 25 μm is formed on the resin layer. Copper plating treatment was performed so as to fill. Next, curing was performed at 190 ° C. for 60 minutes in a hot-air circulating drying furnace to obtain a completely cured copper-plated test substrate.
The obtained test substrate was subjected to thermal history with one cycle of −65 ° C. for 30 minutes and 150 ° C. for 30 minutes. After 2000 cycles, in order to observe the state of the via bottom and the wall surface with an optical microscope, the via center was cut and polished with a precision cutting machine, and the cross-sectional state was observed. Evaluation criteria were evaluated according to the following. The number of observation vias was 100 holes.
○: No crack occurrence Δ: Crack occurrence rate 1 to less than 10% ×: Crack occurrence rate 10% or more

<BHAST resistance>
A dry film is laminated to a BT substrate on which comb-shaped electrodes (line / space = 20 microns / 15 microns) are formed, and heated at 180 ° C. for 60 minutes to form a cured film of the resin layer, thereby creating an evaluation substrate. did. The evaluation substrate was placed in a high-temperature and high-humidity tank under an atmosphere of 130 ° C. and 85% humidity, charged with a voltage of 5.5 V, and subjected to a HAST test in the tank for various times. The insulation resistance value in the tank at various times of the cured film of the resin layer was evaluated according to the following criteria.
◎: After 10 hours, 10 ⁸ Ω or more ○: After 240 hours, 10 ⁸ Ω or more Δ: After 200 hours, 10 ⁸ Ω or more ×: After 200 hours, less than 10 ⁸ Ω

<Solubility of thermoplastic resin in solvent>
The solubility with respect to the solvent of the thermoplastic resin which the dry film of each Example and a comparative example contains was investigated as follows. The evaluation results are shown in Tables 5-8.

The solvent used by each Example and a comparative example was mixed by the same ratio as the ratio of Tables 1-4, and the mixed solvent was created. Each of the thermoplastic resins used in Examples and Comparative Examples was dissolved in the mixed solvent as described below.
1) YX6954:
70 parts of a mixed solvent was blended with 30 parts of YX6954 and dissolved by heating at a temperature lower than the boiling point of each component while stirring.
2) FX-293:
Forty parts of FX-293 were mixed with 60 parts of a mixed solvent, and heated and dissolved at a temperature lower than the boiling point of each component while stirring.
3) KS-1:
30 parts of KS-1 was blended with 60 parts of a mixed solvent, and heated and dissolved at a temperature lower than the boiling point of each component while stirring.
A mixture of each thermoplastic resin and mixed solvent was heated and dissolved, and then cooled to room temperature to produce a film having a thickness of 1 mm. The produced film was observed with an optical microscope at a magnification of 25 times, and it was confirmed whether or not a solid substance was deposited in a range of 1 cm × 1 cm.
○: Coarse particles of 20 μm or more are not seen at all.
X: One or more coarse particles of 20 μm or more are seen.
In Examples and Comparative Examples containing a plurality of thermoplastic resins, the precipitation of solids was confirmed for each thermoplastic resin in the same manner as described above, and coarse particles of 20 μm or more were found at all for all the thermoplastic resins contained. When it was not possible, it evaluated as "(circle)", when one or more coarse particles 20 micrometers or more were seen about at least 1 type of the thermoplastic resin to contain, it evaluated as "x".

＊３９：ラミネート後、キャリアフィルムを剥がした際に、キャリアフィルムに樹脂層由来の樹脂が多量に付着したため、特性試験ができなかった。

* 39: When the carrier film was peeled off after laminating, a large amount of resin derived from the resin layer adhered to the carrier film, so the characteristic test could not be performed.

From the results shown in Tables 5 to 8, it can be seen that in the case of the dry films of Examples 1 to 19, it is possible to obtain a resin layer that is excellent in peelability from the carrier film and suppresses cracking and powder falling.
On the other hand, although it contains two or more solvents, the dry film of Comparative Example 1 containing only one solvent having a boiling point of 100 ° C. or higher, and two solvents having a boiling point of 100 ° C. or higher, the boiling point thereof However, the dry film of Comparative Example 3 in which the carrier film is almost the same has poor peelability of the carrier film, and a large amount of the resin layer is peeled off when the carrier film is peeled off. I understand. Moreover, since the resin layers of the dry films of Comparative Examples 1 and 3 were sticky, bubbles remained when they were laminated on the base material.
As a solvent, the dry film of Comparative Example 2 containing only a solvent having a boiling point of less than 100 ° C. was excellent in the peelability of the carrier film, but the resin layer was not flexible, and cracking and powder falling occurred. Moreover, the cured film of the resin layer obtained using the dry film of Comparative Example 2 was inferior in solder heat resistance, thermal cycle resistance, and insulation.

DESCRIPTION OF SYMBOLS 1 Insulating board 3 Inner layer conductor pattern 3a Connection part 4, 9 Resin insulating layer 8 Outer layer conductor pattern 10 Outermost layer conductor pattern 20 Through hole 21 Through hole hole 22 Connection part 30a Test tube for liquid determination 30b Test tube 31 for temperature measurement Mark (Line A)
32 Mark (B line)
33a, 33b Rubber plug 34 Thermometer X Multilayer substrate

Claims (5)

A dry film having a resin layer containing a thermosetting resin component, a filler, and at least two solvents,
The at least two kinds of solvents each have a boiling point of 100 ° C. or higher and a boiling point of 5 ° C. or higher,
A dry film comprising any one of a phenoxy resin, a polyvinyl acetal resin, a thermoplastic polyhydroxy polyether resin having a fluorene skeleton, a block copolymer, and rubber-like particles.   2. The dry film according to claim 1, wherein the ratio of the residual content of the solvent is 0.1 to 4% by weight based on the total amount of the resin layer of the dry film containing the solvent.   The dry film according to claim 1 or 2, further comprising an epoxy compound as the thermosetting resin component, and further containing a curing agent.   It is an object for printed wiring board manufacture, The dry film of any one of Claims 1-3 characterized by the above-mentioned.   A printed wiring board comprising a cured product obtained by curing the resin layer of the dry film according to claim 1.

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