WO2017122460A1

WO2017122460A1 - Dry film and printed wiring board

Info

Publication number: WO2017122460A1
Application number: PCT/JP2016/086192
Authority: WO
Inventors: 遠藤　新; 英司播磨; 貴幸中条; 諭興津; 良朋青山
Original assignee: 太陽インキ製造株式会社
Priority date: 2016-01-13
Filing date: 2016-12-06
Publication date: 2017-07-20
Also published as: JP6937701B2; KR20180103101A; TW201801584A; JPWO2017122460A1; TWI721070B; CN108476589A; KR102641274B1; CN108476589B

Abstract

To provide: a dry film having a resin layer that has excellent embeddability and planarity; and a printed wiring board which is provided with a cured product that is obtained by curing this dry film. A dry film which comprises a film and a resin layer that is formed on the film and contains an epoxy resin, and which is characterized in that: the resin layer has a melt viscosity of 60-5,500 dPa·s at 100°C; the resin layer has a storage elastic modulus of 80-5,500 Pa at 100°C; the resin layer contains, as the epoxy resin, at least a liquid epoxy resin; and the content of the liquid epoxy resin is less than 60% by mass of the total mass of the epoxy resin.

Description

Dry film and printed wiring board

The present invention relates to a dry film and a printed wiring board, and more particularly to a dry film having a resin layer excellent in embedding property and flatness, and a printed wiring board having a cured product obtained by curing the dry film.

Conventionally, a dry film has been used as one of means for forming a protective film or an insulating layer such as a solder resist or an interlayer insulating layer provided on a printed wiring board used in an electronic device or the like (for example, Patent Documents 1 to 3). . A dry film has a resin layer obtained by applying a curable resin composition having desired characteristics on a carrier film and then undergoing a drying process, and generally protects the surface opposite to the carrier film. The protective film for carrying out is distribute | circulating in the market in the state laminated | stacked further. By laminating the resin layer of the dry film on a substrate having a circuit pattern and then performing patterning and curing treatment, the above protective film and insulating layer can be formed on the printed wiring board.

JP 7-15119 A (Claims) JP 2002-162736 A (Claims) JP 2003-131366 A (Claims)

When laminating a resin layer of a dry film on a substrate, the resin layer is not sufficiently embedded in the unevenness of the circuit pattern on the substrate, and bubbles may be generated between the resin layer and the substrate. Such air bubbles sometimes impair the adhesion between the resin layer and the substrate.

In addition, vacuum laminating and pressing are performed to flatten the outer surface of the resin layer of the dry film after lamination, but the unevenness of the circuit pattern on the substrate is transferred to the outer surface. The flatness was not enough. In particular, printed circuit boards have been made thinner and the resin layer of the dry film has been required to be thinner due to the recent trend of light and thin electronic devices. Thereby, even if vacuum lamination or pressing is performed, it is difficult to obtain the embedding property of the resin layer in the base material and the flatness of the outer surface of the resin layer.

Accordingly, an object of the present invention is to provide a dry film having a resin layer excellent in embedding property and flatness, and a printed wiring board having a cured product obtained by curing the dry film.

As a result of intensive studies by the inventors in view of the above, the melt viscosity at 100 ° C. is 60 to 5500 dPa · s, the storage elastic modulus at 100 ° C. is 10 to 5500 Pa, and the liquid epoxy resin is 60% of the total amount of epoxy resin. The present inventors have found that the above problems can be solved by using a dry film having a resin layer contained at less than% by mass, and have completed the present invention.

That is, the dry film of the present invention is a dry film having a film and a resin layer containing an epoxy resin formed on the film, and the resin layer has a melt viscosity of 60 to 5500 dPa · s at 100 ° C. The storage modulus of the resin layer is 80 to 5500 Pa at 100 ° C., and the resin layer contains at least a liquid epoxy resin as the epoxy resin,
Content of the said liquid epoxy resin is less than 60 mass% with respect to the said epoxy resin total mass, It is characterized by the above-mentioned.

In the dry film of the present invention, the amount of residual solvent in the resin layer is preferably 1.0 to 7.0% by mass.

The dry film of the present invention contains at least two organic solvents selected from the group consisting of N, N-dimethylformamide, toluene, cyclohexanone, aromatic hydrocarbons having 8 or more carbon atoms, and methyl ethyl ketone in the resin layer. It is preferable.

In the dry film of the present invention, the resin layer further comprises at least one semi-solid epoxy resin selected from the group consisting of a bisphenol A type epoxy resin, a naphthalene type epoxy resin, and a phenol novolac type epoxy resin as the epoxy resin. It is preferable to include.

In the dry film of the present invention, the resin layer preferably contains a filler, and the filler has an average particle size of 0.1 to 10 μm.

In the dry film of the present invention, the resin layer contains a filler, and the content of the filler is 40 to 80% by mass per total resin layer (the total amount excluding the solvent when the resin layer contains a solvent). preferable.

In the dry film of the present invention, the resin layer includes a filler, and the filler includes a silane coupling agent having an epoxy group, a silane coupling agent having an amino group, a silane coupling agent having a mercapto group, and an isocyanate group. Surface treatment with at least one of a silane coupling agent having a vinyl group, a silane coupling agent having a vinyl group, a silane coupling agent having a styryl group, a silane coupling agent having an acrylic group, and a silane coupling agent having a methacryl group It is preferable that

The cured product of the present invention is obtained by curing the resin layer of the dry film.

The printed wiring board of the present invention is characterized by comprising the cured product.

According to the present invention, it is possible to provide a dry film having a resin layer excellent in embedding property and flatness, and a printed wiring board comprising a cured product obtained by curing the dry film.

It is a schematic sectional drawing which shows typically one embodiment of the laminated structure of this invention. It is a schematic sectional drawing which shows typically another embodiment of the laminated structure of this invention. It is a schematic side view which shows the two test tubes used for the liquid determination of the epoxy resin.

<Dry film>
The dry film of the present invention is a dry film having a film and a resin layer formed on the film, wherein the resin layer has a melt viscosity of 60 to 5500 dPa · s at 100 ° C. And the resin layer contains at least a liquid epoxy resin as the epoxy resin, and the content of the liquid epoxy resin is 60% by mass with respect to the total amount of the epoxy resin. It is characterized by being less than. Although the detailed mechanism is not clear, both the melt viscosity and the storage elastic modulus of the resin layer are adjusted to the above ranges, and the ratio of the liquid epoxy resin contained in the resin layer to the total amount of the epoxy resin is less than 60% by mass. As a result, embedding and flatness are remarkably improved.

In addition, according to the dry film of the present invention, a cured film having a flat surface can be formed. Therefore, when a plating resist is formed on the dry film, omission of the plating resist line and development failure can be suppressed. . That is, according to the dry film of the present invention, a cured product having excellent plating resist formability can be obtained. As a result, a high-definition conductive circuit can be formed on the resin layer.
On the other hand, when the melt viscosity of the resin layer of the dry film is less than 60 dPa · s at 100 ° C. or the storage elastic modulus of the resin layer is less than 80 Pa at 100 ° C., it becomes easy to entrap bubbles when laminating the dry film, and the embedding property is improved. It becomes difficult to obtain. On the other hand, when the melt viscosity of the resin layer exceeds 5500 dPa · s at 100 ° C. or the storage elastic modulus of the resin layer exceeds 5500 Pa at 100 ° C., it becomes difficult to obtain flatness of the outer surface of the resin layer. The melt viscosity of the resin layer is preferably 400 to 3000 dPa · s at 100 ° C., and the storage elastic modulus of the resin layer is preferably 100 to 3500 Pa at 100 ° C. Further, when the content of the liquid epoxy resin is 60% by mass or more with respect to the total amount of the epoxy resin, it is difficult to obtain the embedding property of the dry film and the flatness of the outer surface of the resin layer.

It is preferable that the melt viscosity of the resin layer is 3000 dPa · s or less at 100 ° C. and the storage elastic modulus of the resin layer is 3000 Pa or less at 100 ° C. because of excellent flatness and plating resist formation.

When the melt viscosity of the resin layer is 100 dPa · s or more at 100 ° C. and the storage elastic modulus of the resin layer is 100 Pa or more at 100 ° C., it is preferable because bubbles are less likely to be entrained during lamination and the embedding property is more excellent. .

More preferably, the melt viscosity of the resin layer is 500 to 3000 dPa · s at 100 ° C., and the storage elastic modulus of the resin layer is 500 to 3000 Pa at 100 ° C.

The method for adjusting the melt viscosity and storage modulus of the resin layer is not particularly limited, but can be easily adjusted by selecting the blending amount, particle size, type, and the like of the filler as described later. Moreover, it can adjust also with a thermosetting component or a hardening | curing agent.

FIG. 1 is a schematic sectional view showing an embodiment of the dry film of the present invention. The resin layer 12 is a dry film 11 having a two-layer structure formed on the film 13. Further, as shown in FIG. 2, a dry film having a three-layer structure in which a resin layer 22 is formed on the first film 23 and a second film 24 is further laminated to protect the surface of the resin layer 22. 21 may be sufficient. If necessary, another resin layer may be provided between the film and the resin layer.

[Resin layer]
The resin layer of the dry film of the present invention is in a state generally referred to as a B stage state, and is obtained from a curable resin composition. Specifically, the resin layer of the dry film is obtained through a drying process after applying the curable resin composition to the film. As long as the said curable resin composition satisfy | fills the said melt viscosity, storage elastic modulus, and the compounding quantity of a liquid epoxy resin, the kind and compounding quantity of another component are not specifically limited. The film thickness of the resin layer is not particularly limited, and for example, the film thickness after drying may be 1 to 200 μm. However, the thinner the resin layer, the more prominent the effect of the present invention. Specifically, the film thickness of the resin layer is preferably 30 μm or less, more preferably 20 μm or less, and even more preferably 15 μm or less, since the effects of the present invention are easily exhibited.

The resin layer includes an epoxy resin. The epoxy resin is a resin having an epoxy group, and any conventionally known one can be used. Examples thereof include a bifunctional epoxy resin having two epoxy groups in the molecule, and a polyfunctional epoxy resin having many epoxy groups in the molecule. Note that a hydrogenated epoxy resin may be used. The resin layer contains, as the epoxy resin, a liquid epoxy resin with a content of less than 60% by mass based on the total mass of the epoxy resin. The resin layer contains at least one of a solid epoxy resin and a semi-solid epoxy resin as an epoxy resin other than the 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. 3, 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 mouth of the test tube sealed with a rubber member 33a, and a rubber plug 33b having the same size and the same marked line with 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 to 50 ° C) specified in JIS B7410 (1982) "Petroleum test glass thermometer" is used, but the temperature is 0 to 50 ° C. It is sufficient if the range can be measured.

(2) Test procedure The liquid test tube 30a shown in FIG. 3 (a) and the temperature measurement test shown in FIG. 3 (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 state is maintained as it is 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.

Solid epoxy resins include HP-4700 (naphthalene type epoxy resin) manufactured by DIC, EXA4700 (tetrafunctional naphthalene type epoxy resin) manufactured by DIC, and NC-7000 (polyfunctional solid epoxy resin containing naphthalene skeleton) manufactured by Nippon Kayaku Co., Ltd. Naphthalene type epoxy resin such as EPPN-502H (Trisphenol epoxy resin) manufactured by Nippon Kayaku Co., Ltd. Epoxy product of a condensate of phenols and aromatic aldehyde having a phenolic hydroxyl group (Trisphenol type epoxy resin); DIC Dicyclopentadiene aralkyl epoxy resin such as Epicron HP-7200H (dicyclopentadiene skeleton-containing polyfunctional solid epoxy resin) manufactured by Nihon Kayaku Co., Ltd .; biphenyl aralkyl such as NC-3000H (biphenyl skeleton-containing polyfunctional solid epoxy resin) manufactured by Nippon Kayaku Co., Ltd. Type epoch Biphenyl / phenol novolac 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., and the like.

Semi-solid epoxy resins include DIC's Epicron 860, Epicron 900-IM, Epicron EXA-4816, Epicron EXA-4822, Asahi Ciba's Araldite AER280, Toto Kasei's Epoto YD-134, Mitsubishi Chemical's 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 novolac type epoxy resin such as Epicron N-740 manufactured by DIC .
The semisolid epoxy resin preferably contains at least one selected from the group consisting of bisphenol A type epoxy resins, naphthalene type epoxy resins and phenol novolac type epoxy resins. By including those semi-solid epoxy resins, the glass transition temperature (Tg) of the cured product is high, the CTE is low, and the crack resistance is excellent.

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.

Epoxy resin can be used in combination of two or more. The compounding amount of the epoxy resin is preferably 5 to 50% by mass, more preferably 5 to 40% by mass, and further preferably 5 to 35% by mass based on the total amount of the resin layer of the dry film excluding the solvent. preferable. The content of the liquid epoxy resin is preferably 5 to 45% by mass, more preferably 5 to 40% by mass, and particularly preferably 5 to 30% by mass with respect to the total mass of the epoxy resin. .

The resin layer preferably 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, conventionally known inorganic fillers and organic fillers can be used and are not limited to specific ones, but inorganic fillers that suppress the curing shrinkage of the coating film and contribute to the improvement of properties such as adhesion and hardness are preferred. As the inorganic filler, for example, barium sulfate, barium titanate, barium zirconate titanate, strontium titanate, calcium titanate, calcium zirconate, magnesium titanate, bismuth titanate, barium neodymium titanate, barium tin titanate, Silica such as lead titanate, amorphous silica, crystalline silica, fused silica, spherical silica, talc, clay, Neuburg silica particles, boehmite, magnesium carbonate, calcium carbonate, titanium oxide, aluminum oxide, aluminum hydroxide, silicon nitride And extender pigments such as aluminum nitride, and metal powders such as copper, tin, zinc, nickel, silver, palladium, aluminum, iron, cobalt, gold and platinum.
Among the above fillers, barium titanate, barium zirconate titanate, strontium titanate, calcium titanate, calcium zirconate, magnesium titanate, bismuth titanate, barium neodymium titanate, barium tin titanate, lead titanate, oxidation Use of titanium is preferable because the dielectric constant can be increased and the concealability of the circuit can be improved.
The inorganic filler is preferably spherical particles. The average particle size of the filler is preferably 0.1 to 10 μm. In the present specification, the average particle size of the filler is not only the particle size of the primary particles but also the average particle size including the particle size of the secondary particles (aggregates). The average particle size can be determined by a laser diffraction particle size distribution measuring device. An example of a measuring apparatus using the laser diffraction method is Nanotrac wave manufactured by Nikkiso Co., Ltd.

The inorganic filler is preferably surface-treated. As the surface treatment, a surface treatment with a coupling agent is preferable. As the coupling agent, a silane coupling agent, a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent, or the like can be used. Among these, a silane coupling agent is preferable.

As the silane coupling agent, as an organic group, a silane coupling agent having an epoxy group, a silane coupling agent having an amino group, a silane coupling agent having a mercapto group, a silane coupling agent having an isocyanate group, a vinyl group. A silane coupling agent having a styryl group, a silane coupling agent having a methacryl group, a silane coupling agent having an acryl group, or the like can be used. In particular, a silane coupling agent having an epoxy group and a silane coupling agent having an amino group are preferable because of excellent adhesion to a base circuit.

The inorganic filler may be subjected to a surface treatment such as alumina treatment that does not introduce an organic group.

The surface-treated inorganic filler only needs to be blended in the resin layer of the dry film in a surface-treated state. When adjusting the curable resin composition, the surface-untreated inorganic filler and the surface treatment agent are separately separated. Although an inorganic filler may be surface-treated in the composition by blending, it is preferable to blend an inorganic filler that has been surface-treated in advance when adjusting the curable resin composition. By blending a surface-treated inorganic filler in advance, the flatness after curing of the resin layer and the formability of the plating resist are further improved, and the dielectric loss tangent after humidification is excellent. When the surface treatment is performed in advance, it is preferable to blend a pre-dispersion liquid in which an inorganic filler is pre-dispersed in a solvent. The surface-treated inorganic filler is pre-dispersed in a solvent and the pre-dispersion liquid is blended in the composition, or More preferably, after pre-dispersing the untreated inorganic filler in the solvent, the pre-dispersed liquid is blended into the composition.
Here, when silica surface-treated with a silane coupling agent having a vinyl group in advance is blended, the dielectric loss tangent after humidification is excellent. Moreover, when the alumina surface-treated with a silane coupling agent having a vinyl group in advance is blended, heat dissipation is excellent.

The blending amount of the filler is preferably 25 to 85% by mass, and more preferably 40 to 85% by mass based on the total amount of the resin layer of the dry film excluding the solvent. When the blending amount of the filler is 25 to 85% by mass, the embedding property is excellent. A linear expansion coefficient can be made low as it is 25 mass% or more, and it is excellent in the thermal radiation characteristic.
Further, it is preferable to use two or more kinds of fillers in combination because they are excellent in flatness and plating resist formability. Here, when a nanofiller having an average primary particle size of 100 nm or less is included as a filler, the filling efficiency of the filler can be increased. Thereby, the dielectric loss tangent after humidification can be made low, a linear expansion coefficient can be made small, and the crack tolerance at the time of the thermal cycle after reflow can be improved.

The amount of residual solvent in the resin layer is preferably 1.0 to 7.0% by mass, more preferably 3.0 to 5.0% by mass, and 3.5 to 4.5% by mass. Even more preferably. When the residual solvent is 7.0% by mass or less, bumping at the time of thermosetting is suppressed, and the surface flatness is improved. Moreover, it can suppress that melt viscosity falls too much and resin flows, and flatness becomes favorable. When the residual solvent is 1.0% by mass or more, the fluidity during lamination is good, and the flatness and embedding are good. Further, when the residual solvent is 3.0 to 5.0% by mass, the handleability and the coating film characteristics of the dry film are excellent.

It is preferable that the resin layer contains at least two organic solvents selected from the group consisting of N, N-dimethylformamide, toluene, cyclohexanone, aromatic hydrocarbons having 8 or more carbon atoms, and methyl ethyl ketone. When a resin composition containing such an organic solvent is used for forming the resin layer, it becomes easy to obtain a drying margin. That is, the drying time can be increased and the degree of freedom of the drying time is improved.

The curable resin composition is a thermosetting resin composition containing an epoxy resin such as a liquid epoxy resin. As specific examples, a photocurable thermosetting resin composition, a thermosetting resin composition, and photopolymerization start. Photocurable Thermosetting Resin Composition Containing Photoagent, Photocurable Thermosetting Resin Composition Containing Photobase Generator, Photocurable Thermosetting Resin Composition Containing Photoacid Generator, Negative Type Photocurable thermosetting resin composition and positive photosensitive thermosetting resin composition, alkali development type photocurable thermosetting resin composition, solvent development type photocurable thermosetting resin composition, swelling release type Examples include, but are not limited to, thermosetting resin compositions and melt-peelable thermosetting resin compositions. Examples of the epoxy resin such as a liquid epoxy resin include those exemplified as the epoxy resin contained in the resin layer.

(Photo-curable thermosetting resin composition)
As an example of the photocurable thermosetting resin composition, a resin composition containing a carboxyl group-containing resin and a photopolymerization initiator in addition to the epoxy resin will be described below.

The carboxyl group-containing resin can be rendered alkali developable by containing a carboxyl group. From the viewpoint of photocurability and development resistance, it is preferable to have an ethylenically unsaturated bond in the molecule in addition to the carboxyl group, but only a carboxyl group-containing resin having no ethylenically unsaturated bond is used. May be. When the carboxyl group-containing resin does not have an ethylenically unsaturated bond, a compound (photosensitive monomer) having one or more ethylenically unsaturated bonds in the molecule is used in order to make the composition photocurable. There is a need. As the ethylenically unsaturated bond, those derived from acrylic acid, methacrylic acid or derivatives thereof are preferable. Among the carboxyl group-containing resins, there are carboxyl group-containing resins having a copolymer structure, carboxyl group-containing resins having a urethane structure, carboxyl group-containing resins starting from an epoxy resin, and carboxyl group-containing resins starting from a phenol compound. preferable. Specific examples of the carboxyl group-containing resin include compounds listed below (which may be either oligomers or polymers).

(1) A bifunctional or higher polyfunctional epoxy resin as described later is reacted with (meth) acrylic acid, and a hydroxyl group present in the side chain is reacted with 2 such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc. A carboxyl group-containing photosensitive resin to which a basic acid anhydride is added. Here, the bifunctional or higher polyfunctional epoxy resin is preferably solid.

(2) A polyfunctional epoxy resin obtained by epoxidizing a hydroxyl group of a bifunctional epoxy resin as described later with epichlorohydrin is reacted with (meth) acrylic acid, and a dibasic acid anhydride is added to the resulting hydroxyl group. A carboxyl group-containing photosensitive resin. Here, the bifunctional epoxy resin is preferably solid.

(3) An epoxy compound having two or more epoxy groups in one molecule is combined with a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, and (meth) acrylic acid or the like. Polybasic, such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid, etc., with respect to the alcoholic hydroxyl group of the reaction product obtained by reacting with a saturated carboxylic acid containing monocarboxylic acid A carboxyl group-containing photosensitive resin obtained by reacting an acid anhydride.

(4) Two or more per molecule such as bisphenol A, bisphenol F, bisphenol S, novolac type phenol resin, poly-p-hydroxystyrene, condensate of naphthol and aldehydes, condensate of dihydroxynaphthalene and aldehydes Reaction obtained by reacting an unsaturated group-containing monocarboxylic acid such as (meth) acrylic acid with a reaction product obtained by reacting a compound having a phenolic hydroxyl group with an alkylene oxide such as ethylene oxide or propylene oxide A carboxyl group-containing photosensitive resin obtained by reacting a product with a polybasic acid anhydride.

(5) A reaction product obtained by reacting a compound having two or more phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate is reacted with an unsaturated group-containing monocarboxylic acid. A carboxyl group-containing photosensitive resin obtained by reacting the resulting reaction product with a polybasic acid anhydride.

(6) Diisocyanate compounds such as aliphatic diisocyanate, branched aliphatic diisocyanate, alicyclic diisocyanate, aromatic diisocyanate, polycarbonate polyol, polyether polyol, polyester polyol, polyolefin polyol, acrylic polyol, bisphenol A type A terminal carboxyl group-containing urethane resin obtained by reacting an acid anhydride with a terminal of a urethane resin by a polyaddition reaction of a diol compound such as an alkylene oxide adduct diol, a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(7) During synthesis of a carboxyl group-containing urethane resin by a polyaddition reaction between a diisocyanate, a carboxyl group-containing dialcohol compound such as dimethylolpropionic acid or dimethylolbutyric acid, and a diol compound, a molecule such as hydroxyalkyl (meth) acrylate A carboxyl group-containing urethane resin in which a compound having one hydroxyl group and one or more (meth) acryloyl groups is added and terminally (meth) acrylated.

(8) During synthesis of a carboxyl group-containing urethane resin by polyaddition reaction of a diisocyanate, a carboxyl group-containing dialcohol compound, and a diol compound, an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate, etc. A carboxyl group-containing urethane resin obtained by adding a compound having two isocyanate groups and one or more (meth) acryloyl groups, and then terminally (meth) acrylating.

(9) Carboxy group-containing photosensitivity obtained by copolymerization of unsaturated carboxylic acid such as (meth) acrylic acid and unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, and isobutylene. resin.

(10) To a carboxyl group-containing polyester resin obtained by reacting a polyfunctional oxetane resin with a dicarboxylic acid such as adipic acid, phthalic acid or hexahydrophthalic acid and adding a dibasic acid anhydride to the primary hydroxyl group produced. Further, a carboxyl group-containing photosensitive resin obtained by adding a compound having one epoxy group and one or more (meth) acryloyl groups in one molecule, such as glycidyl (meth) acrylate and α-methylglycidyl (meth) acrylate .

(11) A carboxyl group-containing photosensitive resin obtained by adding a compound having a cyclic ether group and a (meth) acryloyl group in one molecule to the carboxyl group-containing resin of any one of (1) to (10) described above.

In addition, here, (meth) acrylate is a term that collectively refers to acrylate, methacrylate, and a mixture thereof, and the same applies to other similar expressions below.

The acid value of the carboxyl group-containing resin is preferably 40 to 150 mgKOH / g. When the acid value of the carboxyl group-containing resin is 40 mgKOH / g or more, alkali development is improved. In addition, by setting the acid value to 150 mgKOH / g or less, it is possible to easily draw a normal resist pattern. More preferably, it is 50 to 130 mgKOH / g.

The blending amount of the carboxyl group-containing resin is preferably 20 to 60% by mass based on the total amount of the resin layer of the dry film excluding the solvent. Coating strength can be improved by setting it as 20 mass% or more. Further, when the content is 60% by mass or less, viscosity becomes appropriate and workability is improved. More preferably, it is 20 to 50% by mass.

As the photopolymerization initiator, known ones can be used, and among them, an oxime ester photopolymerization initiator having an oxime ester group, an α-aminoacetophenone photopolymerization initiator, an acylphosphine oxide photopolymerization initiator. Agents and titanocene photopolymerization initiators are preferred. A photoinitiator may be used individually by 1 type and may be used in combination of 2 or more type.
The blending amount of the photopolymerization initiator is, for example, 0.1 to 30 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin.

When the oxime ester photopolymerization initiator is used, the blending amount is preferably 0.01 to 5 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. By setting it as 0.01 mass part or more, photocurability on copper becomes more reliable and coating-film characteristics, such as chemical resistance, improve. Moreover, the light absorption in the coating-film surface is suppressed by setting it as 5 mass parts or less, and there exists a tendency for the sclerosis | hardenability of a deep part to improve. More preferably, it is 0.5 to 3 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin.

In the case of using an α-aminoacetophenone photopolymerization initiator or an acylphosphine oxide photopolymerization initiator, each compounding amount is 0.01 to 15 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. preferable. By setting it as 0.01 mass part or more, photocurability on copper becomes more reliable and coating-film characteristics, such as chemical resistance, improve. Moreover, by setting it as 15 mass parts or less, sufficient reduction effect of an outgas is acquired, Furthermore, the light absorption in the cured film surface is suppressed, and the sclerosis | hardenability of a deep part improves. More preferably, it is 0.5 to 10 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin.

A photoinitiator or sensitizer may be used in combination with the above-described photopolymerization initiator. Examples of the photoinitiation assistant or sensitizer include benzoin compounds, acetophenone compounds, anthraquinone compounds, thioxanthone compounds, ketal compounds, benzophenone compounds, tertiary amine compounds, and xanthone compounds. These compounds may be used as a photopolymerization initiator in some cases, but are preferably used in combination with a photopolymerization initiator. Moreover, a photoinitiator auxiliary or a sensitizer may be used individually by 1 type, and may use 2 or more types together.

The photocurable thermosetting resin composition may contain a thermosetting component other than the epoxy resin for the purpose of improving characteristics such as heat resistance and insulation reliability. Such thermosetting components include known and commonly used thermosetting resins such as isocyanate compounds, blocked isocyanate compounds, amino resins, maleimide compounds, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, polyfunctional oxetane compounds, and episulfide resins. Can be used.

The blending amount of the thermosetting component is preferably 10 to 100 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin.

The photocurable thermosetting resin composition preferably contains a thermosetting catalyst. Examples of such thermosetting catalysts include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole. Imidazole derivatives such as 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N -Amine compounds such as dimethylbenzylamine and 4-methyl-N, N-dimethylbenzylamine; hydrazine compounds such as adipic acid dihydrazide and sebacic acid dihydrazide; and phosphorus compounds such as triphenylphosphine. Guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino S-triazine derivatives such as -S-triazine / isocyanuric acid adducts and 2,4-diamino-6-methacryloyloxyethyl-S-triazine / isocyanuric acid adducts can also be used. A compound that also functions in combination with a thermosetting catalyst.

The blending amount of the thermosetting catalyst is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15.0 parts by mass with respect to 100 parts by mass of the epoxy resin.

The photocurable thermosetting resin composition may contain a photosensitive monomer in addition to the above-described carboxyl group-containing resin, photopolymerization initiator, and epoxy resin. The photosensitive monomer is a compound having one or more ethylenically unsaturated bonds in the molecule. The photosensitive monomer assists photocuring of the carboxyl group-containing resin by irradiation with active energy rays.

Examples of the compound used as the photosensitive monomer include conventionally known polyester (meth) acrylate, polyether (meth) acrylate, urethane (meth) acrylate, carbonate (meth) acrylate, and epoxy (meth) acrylate. Specifically, hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate; diacrylates of glycols such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol, and propylene glycol; N, N-dimethylacrylamide Acrylamides such as N-methylol acrylamide and N, N-dimethylaminopropyl acrylamide; aminoalkyl acrylates such as N, N-dimethylaminoethyl acrylate and N, N-dimethylaminopropyl acrylate; hexanediol, trimethylolpropane, Polyhydric alcohols such as pentaerythritol, dipentaerythritol, tris-hydroxyethyl isocyanurate or the like Multivalent acrylates such as a thyroxide adduct, a propylene oxide adduct, or an ε-caprolactone adduct; a polyvalent acrylate such as phenoxyacrylate, bisphenol A diacrylate, and ethylene oxide or propylene oxide adducts of these phenols Acrylates; glyceryl diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, polyglycerides of glycidyl ether such as triglycidyl isocyanurate; not limited to the above, polyether polyol, polycarbonate diol, hydroxyl-terminated polybutadiene, Polyurethane polyol such as polyester polyol is directly acrylated or urethane acrylate via diisocyanate It can be used by appropriately selecting from at least one selected from acrylates and melamine acrylates and methacrylates corresponding to the acrylates.

Epoxy acrylate resin obtained by reacting polyfunctional epoxy resin such as cresol novolac type epoxy resin with acrylic acid, and hydroxyl acrylate of the epoxy acrylate resin, hydroxy acrylate such as pentaerythritol triacrylate, and diisocyanate half urethane such as isophorone diisocyanate An epoxy urethane acrylate compound reacted with a compound may be used as the photosensitive monomer. Such an epoxy acrylate resin can improve photocurability without deteriorating the touch drying property.

The compounding amount of the compound having an ethylenically unsaturated bond in the molecule used as the photosensitive monomer is preferably 5 to 100 parts by mass, more preferably 5 to 70 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. It is a ratio. By making the compounding quantity of the compound which has an ethylenically unsaturated bond into 5 mass parts or more, the photocurability of a photocurable thermosetting resin composition improves. Moreover, the coating-film hardness can be improved by making a compounding quantity into 100 mass parts or less.

The photocurable thermosetting resin composition preferably contains a filler in addition to the above-described components, and may contain other components such as a colorant, an elastomer, and a thermoplastic resin. Hereinafter, these components will also be described.

In the photocurable thermosetting resin composition, a filler can be blended as necessary in order to increase the physical strength of the obtained cured product. Although there is no restriction | limiting in particular as a filler, For example, what was illustrated as a filler which the said resin layer contains is mentioned. A filler may be used individually by 1 type and may be used as a mixture of 2 or more types.

The addition amount of the filler is preferably 500 parts by mass or less, more preferably 0.1 to 400 parts by mass, and particularly preferably 0.1 to 300 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. When the addition amount of the filler is 500 parts by mass or less, the viscosity of the photocurable thermosetting resin composition does not become too high, the printability is good, and the cured product is not easily brittle.

The photocurable thermosetting resin composition may contain a colorant. As the colorant, known colorants such as red, blue, green, yellow, black, and white can be used, and any of pigments, dyes, and pigments may be used. However, it is preferable not to contain a halogen from the viewpoint of reducing the environmental burden and affecting the human body.

The addition amount of the colorant is not particularly limited, but is preferably 10 parts by mass or less, particularly preferably 0.1 to 7 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin.

Also, an elastomer can be blended in the photocurable thermosetting resin composition for the purpose of imparting flexibility to the obtained cured product and improving the brittleness of the cured product. Examples of the elastomer include a polyester elastomer, a polyurethane elastomer, a polyester urethane elastomer, a polyamide elastomer, a polyesteramide elastomer, an acrylic elastomer, and an olefin elastomer. In addition, resins obtained by modifying some or all of the epoxy groups of epoxy resins having various skeletons with carboxylic acid-modified butadiene-acrylonitrile rubbers at both ends can also be used. Furthermore, epoxy-containing polybutadiene elastomers, acrylic-containing polybutadiene elastomers, hydroxyl group-containing polybutadiene elastomers, hydroxyl group-containing isoprene elastomers and the like can also be used. One type of elastomer may be used alone, or a mixture of two or more types may be used.

The amount of the elastomer added is preferably 50 parts by mass or less, more preferably 1 to 30 parts by mass, and particularly preferably 5 to 30 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. When the addition amount of the elastomer is 50 parts by mass or less, the alkali developability of the photocurable thermosetting resin composition becomes good, and the developable pot life is not easily shortened.

In addition, the photocurable thermosetting resin composition may contain components such as a block copolymer, an adhesion promoter, an antioxidant, and an ultraviolet absorber as necessary. As these, those known in the field of electronic materials can be used. Also, known and commonly used thickeners such as finely divided silica, hydrotalcite, organic bentonite, montmorillonite, antifoaming agents such as silicones, fluorines, and polymers, leveling agents, imidazoles, thiazoles, triazoles, etc. At least one of known and commonly used additives such as a silane coupling agent, a rust inhibitor, and a fluorescent brightening agent can be blended.

The organic solvent that can be used is not particularly limited, and examples thereof include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, and the like. be able to. More specifically, ketones such as methyl ethyl ketone, cyclohexanone, methyl butyl ketone, methyl isobutyl ketone, and methyl ethyl ketone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl Glycol ethers such as carbitol, butyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether Class: ethyl acetate, butyl acetate, isobutyl acetate, ethylene glycol monoethyl ester Esters such as teracetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol butyl ether acetate; ethanol, propanol, 2-methoxypropanol, n-butanol, isobutyl alcohol, isopentyl alcohol Alcohols such as ethylene glycol and propylene glycol; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha; and N, N-dimethylformamide ( DMF), tetrachloroethylene, turpentine oil and the like. In addition, Maruzen Petrochemical Co., Ltd. Swazol 1000, Swazol 1500, Standard Petroleum Osaka Sales Co., Ltd. Solvesso 100, Solvesso 150, Sankyo Chemical Co., Ltd. Solvent # 100, Solvent # 150, Shell Chemicals Japan Co., Ltd. Shell Sol A100, Shell Sol A150 Organic solvents such as Ipsol No. 100 and Ipsol No. 150 manufactured by Idemitsu Kosan Co., Ltd. may be used. Such an organic solvent may be used individually by 1 type, and may be used as a 2 or more types of mixture.

A conventionally known method may be used as a method for producing a printed wiring board using a dry film having a resin layer made of a photo-curable thermosetting resin composition. For example, in the case of a dry film in which a resin layer is sandwiched between a first film and a second film as shown in FIG. 2, a printed wiring board can be produced by the following method. The second film is peeled off from the dry film to expose the resin layer, and the resin layer of the dry film is laminated on the substrate on which the circuit pattern is formed using a vacuum laminator or the like, and pattern exposure is performed on the resin layer. . The first film may be peeled off either after exposure after lamination or after exposure. Thereafter, by performing alkali development, a patterned resin layer is formed on the substrate, and the patterned resin layer is cured by light irradiation and heat to form a cured coating, thereby producing a printed wiring board. Can do.

(Thermosetting resin composition)
As an example of the thermosetting resin composition, a resin composition containing no epoxy resin and containing an epoxy resin will be described below.

It is preferable to add a filler to the thermosetting resin composition, and the physical strength of the obtained cured product can be increased. Although there is no restriction | limiting in particular as a filler, For example, what was illustrated as a filler which the said resin layer contains is mentioned. A filler may be used individually by 1 type and may be used as a mixture of 2 or more types.

Although there is no restriction | limiting in particular as an organic solvent which can be used, For example, the organic solvent illustrated with the said photocurable thermosetting resin composition is mentioned. An organic solvent may be used individually by 1 type, and may be used as a 2 or more types of mixture.

The thermosetting resin composition can contain a curing agent. Examples of the curing agent include phenol resins, polycarboxylic acids and acid anhydrides thereof, cyanate ester resins, active ester resins, maleimide compounds, and alicyclic olefin polymers. A hardening | curing agent can be used individually by 1 type or in combination of 2 or more types. Here, the dielectric loss tangent after humidification can be lowered by using at least a cyanate ester resin or an active ester resin. In addition, by using at least a cyanate ester resin or a maleimide compound, the crack resistance during the cooling / heating cycle after reflow is improved.
When the resin layer is composed of a thermosetting resin composition, bubbles are likely to be generated when cured at a high temperature, but according to the dry film of the present invention, curing at a high temperature such as a phenol resin, an active ester resin, a cyanate ester resin, etc. Even when it contains a curing agent that requires a small amount of bubbles, it is difficult for bubbles to form after curing. The curing agent preferably has a structure of at least one of a biphenyl skeleton and a naphthol skeleton.

Examples of the phenol resin include a phenol novolak resin, an alkylphenol volac resin, a bisphenol A novolak resin, a dicyclopentadiene type phenol resin, an Xylok type phenol resin, a terpene-modified phenol resin, a cresol / naphthol resin, a polyvinylphenol, and a phenol / naphthol resin. , Α-naphthol skeleton-containing phenol resin, triazine skeleton-containing cresol novolak resin, biphenyl aralkyl type phenol resin, zylock type phenol novolak resin, and the like can be used singly or in combination of two or more. .
Among the phenol resins, the hydroxyl group equivalent is 130 g / eq. The above are preferable, and 150 g / eq. The above is more preferable. Hydroxyl equivalent weight is 130 g / eq. Examples of the phenol resin include a dicyclopentadiene skeleton phenol novolak resin (GDP series, manufactured by Gunei Chemical Co., Ltd.), a zylock type phenol novolac resin (MEH-7800, manufactured by Meiwa Kasei Co., Ltd.), and a biphenylaralkyl type novolak resin (MEH). -7851, manufactured by Meiwa Kasei Co., Ltd.), naphthol aralkyl type curing agent (SN series, manufactured by Nippon Steel & Sumikin Co., Ltd.), triazine skeleton-containing cresol novolac resin (LA-3018-50P, manufactured by DIC), and the like.

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 the phenol compound or naphthol compound 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. The active ester resin may be naphthalenediol alkyl / benzoic acid type.

The maleimide compound is a compound having a maleimide skeleton, and any conventionally known compound can be used. The maleimide compound preferably has two or more maleimide skeletons, and N, N′-1,3-phenylene dimaleimide, N, N′-1,4-phenylene dimaleimide, N, N′-4,4- Diphenylmethane bismaleimide, 1,2-bis (maleimide) ethane, 1,6-bismaleimide hexane, 1,6-bismaleimide- (2,2,4-trimethyl) hexane, 2,2′-bis- [4- (4-maleimidophenoxy) phenyl] propane, 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide, 4-methyl-1,3-phenylenebismaleimide, bis (3-ethyl -5-methyl-4-maleimidophenyl) methane, bisphenol A diphenyl ether bismaleimide, polyphenylmethanemaleimide, Beauty and more preferably at least any one of diamines condensates with these oligomers and maleimide skeleton. The said oligomer is an oligomer obtained by condensing the maleimide compound which is a monomer of the above-mentioned maleimide compounds. A maleimide compound can be used individually by 1 type or in combination of 2 or more types.

The ratio of the functional group in the curing agent that reacts with the functional group such as the epoxy group of the thermosetting component and the functional group in the curing agent that reacts with the functional group is the curing agent functional group / thermosetting reaction. The functional group (equivalent ratio) is preferably in a ratio of 0.2 to 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 thermal curing reaction (equivalent ratio) = 0.2 to 1.5, and more preferably the functional group of the curing agent / functional group capable of thermal curing reaction ( Equivalent ratio) = 0.3 to 1.0.
When the functional group equivalent (g / eq.) Of the phenol resin, cyanate ester resin, active ester resin, and maleimide compound is 200 or more, warpage can be reduced.

The thermosetting resin composition 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 blending amount of the thermoplastic resin is 0.5 to 20% by mass, preferably 0.5 to 10% by mass, based on the total amount of the resin layer excluding the solvent. When the blending amount of the thermoplastic resin is out of the above range, it becomes difficult to obtain a uniform roughened surface state.

Furthermore, the thermosetting resin composition 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, more preferably in the range of 0.2 to 1 μm. The average particle size of the rubber-like particles in the present invention can be determined by a laser diffraction particle size distribution measuring device. For example, rubber-like particles are uniformly dispersed in an appropriate organic solvent by ultrasonic waves, etc., and a particle size distribution of the rubber-like particles is created on a mass basis using Nanotrac wave manufactured by Nikkiso Co., Ltd. It can be measured by doing.

The compounding amount of the rubber-like particles is preferably 0.5 to 10% by mass, more preferably 1 to 5% by mass, based on the total amount of the resin layer excluding the solvent. In the case of 0.5% by mass or more, crack resistance is obtained, and the adhesion strength with a conductor pattern or the like can be improved. When the content is 10% by mass or less, the coefficient of thermal expansion (CTE) decreases, the glass transition temperature (Tg) increases, and the curing characteristics are improved.

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; boron trifluoride amine complexes; 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 and m-aminophenol; polyphenols such as polyvinylphenol, polyvinylphenol bromide, phenol novolac and 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 when it is desired to accelerate the curing, it can be used preferably in the range of 0.01 to 5 parts by mass with respect to 100 parts by mass of the thermosetting component. In the case of a metal catalyst, it is preferably 10 to 550 ppm, preferably 25 to 200 ppm in terms of metal with respect to 100 parts by mass of the thermosetting component.

The thermosetting resin composition may further include, as necessary, conventionally known colorants such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, asbestos, Conventionally known thickeners such as olben, benton and fine silica, adhesion of antifoaming and / or leveling agents such as silicones, fluorines and polymers, thiazoles, triazoles and silane coupling agents Conventionally known additives such as imparting agents, flame retardants, titanates, and aluminum can be used.

As a method for producing a printed wiring board using a dry film having a resin layer made of a thermosetting resin composition, a conventionally known method may be used. For example, in the case of a dry film in which a resin layer is sandwiched between a first film and a second film as shown in FIG. 2, a printed wiring board can be produced by the following method. The second film is peeled off from the dry film, heat laminated to the circuit board on which the circuit pattern is formed, and then thermally cured. The heat curing may be performed in an oven or by a hot plate press. When laminating or hot plate pressing the substrate on which the circuit is formed and the dry film of the present invention, the copper foil or the substrate on which the circuit is formed can be laminated simultaneously. A printed wiring board can be manufactured by forming a pattern or a via hole by laser irradiation or drilling at a position corresponding to a predetermined position on the substrate on which the circuit pattern is formed, and exposing the circuit wiring. At this time, if there is a component (smear) that cannot be completely removed on the circuit wiring in the pattern or via hole, desmear processing is performed. The first film may be peeled off after lamination, after heat curing, after laser processing, or after desmear treatment.

(Photocurable thermosetting resin composition containing a photobase generator)
As an example of a photocurable thermosetting resin composition containing a photobase generator (hereinafter also referred to as a photobase generator-containing composition), in addition to an epoxy resin, an alkali developable resin, a photobase generator, The composition containing is described below.

The alkali-developable resin is a resin that contains one or more functional groups among phenolic hydroxyl groups, thiol groups, and carboxyl groups and that can be developed with an alkaline solution, preferably a compound having two or more phenolic hydroxyl groups, carboxyl Examples thereof include a group-containing resin, a compound having a phenolic hydroxyl group and a carboxyl group, and a compound having two or more thiol groups.

As the carboxyl group-containing resin, a known resin containing a carboxyl group can be used. Due to the presence of the carboxyl group, the resin composition can be made alkali developable. In addition to the carboxyl group, a compound having an ethylenically unsaturated bond in the molecule may be used. In the present invention, the carboxyl group-containing resin does not have an ethylenically unsaturated bond as the carboxyl group-containing resin. It is preferable to use only.

Specific examples of the carboxyl group-containing resin that can be used in the present invention include the following (1) to (11) as the carboxyl group-containing resin included in the photocurable thermosetting resin composition. The compounds as listed (any of oligomers and polymers) may be mentioned.

(12) Diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates; carboxyl group-containing dialcohol compounds such as dimethylolpropionic acid and dimethylolbutanoic acid, polycarbonate polyols, and polyethers A carboxyl group-containing urethane resin by a polyaddition reaction of a diol compound such as a polyol, a polyester-based polyol, a polyolefin-based polyol, an acrylic polyol, a bisphenol A-based alkylene oxide adduct diol, a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(13) Diisocyanate and bifunctional epoxy resin such as bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bixylenol type epoxy resin, biphenol type epoxy resin ( Carboxyl group-containing urethane resin by polyaddition reaction of (meth) acrylate or its partial acid anhydride modified product, carboxyl group-containing dialcohol compound and diol compound.

(14) During the synthesis of the resin of the above (12) or (13), a compound having one hydroxyl group and one or more (meth) acryloyl groups in a molecule such as hydroxyalkyl (meth) acrylate is added, and the terminal ( (Meth) acrylic carboxyl group-containing urethane resin.

(15) During the synthesis of the resin of the above (12) or (13), one isocyanate group and one or more (meth) acryloyl groups are introduced into the molecule, such as an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate. The carboxyl group-containing urethane resin which added the compound which has and was terminally (meth) acrylated.

(16) A polyfunctional epoxy resin as described above is reacted with a saturated monocarboxylic acid, and a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride or hexahydrophthalic anhydride is added to the hydroxyl group present in the side chain. Carboxyl group-containing resin. Here, the polyfunctional epoxy resin is preferably solid.

(17) A carboxyl group-containing polyester resin obtained by reacting a polyfunctional oxetane resin as described later with a dicarboxylic acid and adding a dibasic acid anhydride to the resulting primary hydroxyl group.

(18) A carboxyl group-containing resin obtained by reacting a polybasic acid anhydride with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide. .

(19) A saturated monocarboxylic acid is reacted with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide. A carboxyl group-containing resin obtained by reacting a basic acid anhydride.

(20) A reaction product obtained by reacting a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate, with a saturated monocarboxylic acid. A carboxyl group-containing resin obtained by reacting with a polybasic acid anhydride.

(21) A carboxyl group obtained by reacting a polybasic acid anhydride with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate. Containing resin.

(22) An epoxy compound having a plurality of epoxy groups in one molecule, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol, and a saturated monocarboxylic acid React with acid and react with polybasic acid anhydrides such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid etc. to the alcoholic hydroxyl group of the resulting reaction product Carboxyl group-containing resin obtained by making it.

(23) reacting an epoxy compound having a plurality of epoxy groups in one molecule with a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol; Carboxyl groups obtained by reacting polybasic acid anhydrides such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid with the alcoholic hydroxyl group of the obtained reaction product Containing resin.

(24) One epoxy group and one or more (meth) acryloyl groups in the molecule of glycidyl (meth) acrylate, α-methylglycidyl (meth) acrylate, etc., in addition to the resin of any one of (12) to (23) above A carboxyl group-containing resin formed by adding a group-containing compound.

Such an alkali-developable resin has a large number of carboxyl groups, hydroxyl groups, and the like in the side chain of the backbone polymer, so that development with an alkaline aqueous solution becomes possible.
Further, the hydroxyl group equivalent or carboxyl group equivalent of the alkali developable resin is 80 to 900 g / eq. And more preferably 100 to 700 g / eq. It is. Hydroxyl group equivalent or carboxyl group equivalent is 900 g / eq. In the following cases, adhesion of the pattern layer is obtained, and alkali development becomes easy. On the other hand, the hydroxyl group equivalent or the carboxyl group equivalent is 80 g / eq. The above case is preferable because dissolution of the light-irradiated portion by the developer is suppressed, and a normal resist pattern can be easily drawn without losing lines more than necessary. Further, it is preferable that the carboxyl group equivalent or the phenol group equivalent is large because development is possible even when the content of the alkali-developable resin is small.

The acid value of the alkali developable resin is preferably 40 to 150 mgKOH / g. When the acid value of the alkali-developable resin is 40 mgKOH / g or more, alkali development is improved. In addition, by setting the acid value to 150 mgKOH / g or less, it is possible to easily draw a normal resist pattern. More preferably, it is 50 to 130 mgKOH / g.

The blending amount of the alkali developing resin is preferably 20 to 60% by mass based on the total amount of the resin layer of the dry film excluding the solvent. Coating strength can be improved by setting it as 20 mass% or more. Further, when the content is 60% by mass or less, the viscosity becomes appropriate and the coating property is improved. More preferably, it is 30 to 50% by mass.

One or more photobase generators can function as a catalyst for the addition reaction of the above-mentioned thermoreactive compound when the molecular structure is changed by irradiation with light such as ultraviolet rays or visible light, or when the molecule is cleaved. It is a compound that produces a basic substance. Examples of basic substances include secondary amines and tertiary amines.

Examples of photobase generators include α-aminoacetophenone compounds, oxime ester compounds, acyloxyimino groups, N-formylated aromatic amino groups, N-acylated aromatic amino groups, nitrobenzyl carbamate groups, alkoxybenzyl carbamates. And compounds having a substituent such as a group.

The photobase generator may be used alone or in combination of two or more. The blending amount of the photobase generator in the photobase generator-containing composition is preferably 1 to 50 parts by mass, more preferably 1 to 40 parts by mass with respect to 100 parts by mass of the thermoreactive compound. The amount of 1 part by mass or more is preferable because development is easy.

It is preferable to add a filler to the photobase generator-containing composition, and the physical strength and the like of the resulting cured product can be increased. Although there is no restriction | limiting in particular as a filler, For example, what was illustrated as a filler which the said resin layer contains is mentioned. A filler may be used individually by 1 type and may be used as a mixture of 2 or more types.

If necessary, the photobase generator-containing composition may further contain components such as a mercapto compound, an adhesion promoter, an antioxidant, and an ultraviolet absorber. As these, those known in the field of electronic materials can be used.
The photobase generator-containing composition includes known conventional thickeners such as finely divided silica, hydrotalcite, organic bentonite, and montmorillonite, antifoaming agents such as silicone, fluorine, and polymer. Or well-known and usual additives, such as a leveling agent, a silane coupling agent, a rust preventive agent, can be mix | blended.

As a method for producing a printed wiring board using a dry film having a resin layer composed of a photobase generator-containing composition, a conventionally known method may be used. For example, in the case of a dry film in which a resin layer is sandwiched between a first film and a second film as shown in FIG. 2, a printed wiring board can be produced by the following method. The second film is peeled from the dry film to expose the resin layer, and the dry film is laminated on the substrate on which the circuit pattern is formed using a vacuum laminator or the like. After that, the photobase generator contained in the photobase generator-containing resin composition is activated by negative pattern light irradiation to cure the light irradiated portion, and the negative portion is removed by alkali development to remove the unirradiated portion. A pattern layer of the mold can be formed. The first film may be peeled off either after lamination or after exposure. Moreover, it is preferable to heat a resin layer after light irradiation and before image development. Thereby, a resin layer can fully be hardened and the pattern layer excellent in the hardening characteristic can be obtained. The heating after light irradiation and before development is preferably a temperature at which the unirradiated part is not thermally cured. Moreover, it is preferable to perform thermosetting (post-cure) after development. After development, ultraviolet curing may be performed to activate the photobase generator remaining without being activated at the time of light irradiation, and then heat curing (post-cure) may be performed.

(Positive photosensitive thermosetting resin composition)
As an example of a positive photosensitive thermosetting resin composition, a resin composition containing a compound that generates a carboxyl group by light irradiation in addition to an epoxy resin will be described below.

Among the compounds that generate a carboxyl group by light irradiation, it is preferable to use a naphthoquinonediazide compound. Naphthoquinone diazide compounds are conventionally used in systems that suppress alkali solubility such as carboxyl groups by forming complexes with carboxyl groups and phenolic hydroxyl groups, and then dissociate the complex by subsequent light irradiation to develop alkali solubility. ing. In this case, if the naphthoquinone diazide compound remains in the film, the complex may be dissociated by light irradiation and the solubility may be expressed. Therefore, in the semiconductor field and the like, the remaining naphthoquinone diazide compound will eventually fly at a high temperature. It was removed by that. However, in the field of printed wiring boards, such a high temperature cannot be applied, and since it cannot be used as a permanent coating film from the viewpoint of stability, a naphthoquinone diazide compound has not been actually used. In the present invention, when a naphthoquinone diazide compound is used as a compound that generates a carboxyl group by light irradiation, the naphthoquinone diazide compound remaining in the unexposed part is incorporated into the crosslinked structure during the thermosetting reaction and is stabilized, The film toughness, that is, the bending resistance and the electrical characteristics can be improved without causing the conventional removal problem. In particular, naphthoquinone diazide compound as a compound that generates a carboxyl group by light irradiation is used in combination with polyamideimide resin and thermosetting component to ensure good developability and resolution while ensuring flexibility. This is preferable because it can be improved.

Specific examples of the naphthoquinonediazide compound include, for example, naphthoquinonediazide adduct of tris (4-hydroxyphenyl) -1-ethyl-4-isopropylbenzene (for example, TS533, TS567, TS583, TS593 manufactured by Sanpo Chemical Laboratory Co., Ltd.). ), Naphthoquinonediazide adducts of tetrahydroxybenzophenone (for example, BS550, BS570, BS599 manufactured by Sanpo Chemical Laboratory Co., Ltd.) and the like can be used.

It is preferable to add a filler to the positive photosensitive thermosetting resin composition, and the physical strength of the resulting cured product can be increased. Although there is no restriction | limiting in particular as a filler, For example, what was illustrated as a filler which the said resin layer contains is mentioned. A filler may be used individually by 1 type and may be used as a mixture of 2 or more types.

Specific examples of the alkali-developable resin contained in the positive photosensitive thermosetting resin composition include the carboxyl group-containing resin exemplified in the photocurable thermosetting resin composition, and the photobase generator-containing composition. Examples thereof include alkali developable resins.

The positive photosensitive thermosetting resin composition may contain a thermosetting component other than the epoxy resin for the purpose of improving characteristics such as heat resistance and insulation reliability. As the thermosetting component, known and commonly used thermosetting resins such as isocyanate compounds, blocked isocyanate compounds, amino resins, maleimide compounds, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, polyfunctional oxetane compounds, and episulfide resins can be used. .

The positive photosensitive thermosetting resin composition preferably contains a filler. Although there is no restriction | limiting in particular as a filler, For example, what was illustrated as a filler which the said resin layer contains is mentioned. A filler may be used individually by 1 type and may be used as a mixture of 2 or more types.

The positive photosensitive thermosetting resin composition may contain other components such as a block copolymer, a colorant, an elastomer, and a thermoplastic resin in addition to the components described above. In addition, the positive photosensitive thermosetting resin composition may further contain components such as an adhesion promoter, an antioxidant, and an ultraviolet absorber as necessary. As these, those known in the field of electronic materials can be used. Further, known and commonly used thickeners such as fine silica, hydrotalcite, organic bentonite, montmorillonite, at least one of defoamers and leveling agents such as silicone, fluorine, and polymer, imidazole, and thiazole At least one of known and commonly used additives such as a silane coupling agent such as a triazole or triazole, a rust inhibitor, and a fluorescent brightening agent can be blended.

A conventionally known method may be used as a method for producing a printed wiring board using a dry film having a resin layer made of a positive photosensitive thermosetting resin composition. For example, in the case of a dry film in which a resin layer is sandwiched between a first film and a second film as shown in FIG. 2, a printed wiring board can be produced by the following method. The second film is peeled from the dry film, the resin layer is exposed, and the dry film is laminated on the substrate on which the circuit pattern is formed using a vacuum laminator or the like. Thereafter, the resin layer is irradiated with light in a positive pattern, the resin layer is alkali-developed, and the light irradiation portion is removed, whereby a positive pattern layer can be formed. The first film may be peeled off either after lamination or after exposure. Moreover, a printed wiring board can be manufactured by heat-hardening (post-cure) a resin layer after image development, and hardening | curing an unirradiated part. In the positive photosensitive thermosetting resin composition, a composition that is soluble in an alkali developer is changed by an acid generated by light irradiation, so that a positive pattern can be formed by alkali development.

[the film]
When laminating a dry film having a resin layer sandwiched between a carrier film and a protective film, in many cases, the protective film is peeled off and the surface of the resin layer on the side in contact with the protective film is the base. Laminated to contact the material. However, the carrier film may be peeled and laminated so that the surface of the resin layer on the side in contact with the carrier film is in contact with the substrate. In the present invention, it is preferable that the resin layer is sandwiched between the first film and the second film as shown in FIG. 2 by the carrier film and the protective film. In addition, the film on the side in contact with the surface of the resin layer that comes into contact with the substrate when laminating to the substrate (that is, the laminate surface) is the second film, and the surface in contact with the resin layer of the second film is The arithmetic average surface roughness Ra is preferably from 0.1 to 1.2 μm, more preferably from 0.3 to 1.2 μm, and even more preferably from 0.4 to 1.2 μm. In addition, arithmetic mean surface roughness Ra means the value measured based on JISB0601. The second film may be either a carrier film or a protective film. Preferably, the first film is a carrier film and the second film is a protective film.

The carrier film has a role of supporting the resin layer of the dry film, and is a film to which the curable resin composition is applied when the resin layer is formed. As the carrier film, for example, a polyester film such as polyethylene terephthalate or polyethylene naphthalate, a polyimide film, a polyamideimide film, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a film made of a thermoplastic resin such as a polystyrene film, and Surface-treated paper or the like can be used. Among these, polyester films can be preferably used from the viewpoints of heat resistance, mechanical strength, handleability, and the like. The thickness of the carrier film is not particularly limited, but is appropriately selected depending on the intended use within a range of about 10 to 150 μm. The surface on which the resin layer of the carrier film is provided may be subjected to release treatment. Moreover, the surface which provides the resin layer of a carrier film may form sputter | spatter or ultra-thin copper foil.

The protective film is provided on the surface opposite to the carrier film of the resin layer for the purpose of preventing dust and the like from adhering to the surface of the resin layer of the dry film and improving the handleability. As the protective film, for example, a film made of a thermoplastic resin exemplified for the carrier film, surface-treated paper, and the like can be used. Among these, a polyester film, a polyethylene film, and a polypropylene film are preferable. The thickness of the protective film is not particularly limited, but is appropriately selected depending on the intended use within a range of about 10 to 150 μm. The surface on which the resin layer of the protective film is provided may be subjected to a mold release treatment.

When using a thermoplastic resin film as the second film having the arithmetic average surface roughness Ra as described above, a filler is added to the resin when forming the film, or the film surface is blasted. Alternatively, the surface can be made into a predetermined form by hairline processing, mat coating, chemical etching, or the like, and a thermoplastic resin film having the arithmetic average surface roughness Ra can be obtained. For example, when a filler is added to the resin, the arithmetic average surface roughness Ra can be controlled by adjusting the particle size and the addition amount of the filler. In the case of blasting, the arithmetic average surface roughness Ra can be controlled by adjusting processing conditions such as blasting material and blast pressure. A commercially available thermoplastic resin film having such a surface roughness may be used. For example, Lumirror X42, Lumirror X43, Lumirror X44 manufactured by Toray Industries, Inc., Emblet PTH-12, Emblet PTH manufactured by Unitika -25, emblet PTHA-25, emblet PTH-38, Alfane MA-411, MA-420, E-201F and ER-440 manufactured by Oji F-Tex.

The first film preferably has an arithmetic average surface roughness Ra of 0.1 μm or less on the surface in contact with the resin layer. When the thickness is 0.1 μm or less, the flatness of the surface of the resin layer after curing becomes good and the glossiness becomes good. Also, if there is a difference in the arithmetic average surface roughness Ra between the first film and the second film, it will be easier to recognize which film is visually (whether it is glossy) and prevent work mistakes. it can.

Also, the thickness A of the first film is preferably larger than the thickness B of the second film because the second film can be easily peeled off. More preferably, the difference (A−B) between the thickness A and the thickness B is 1 μm or more. Further, if there is a difference in thickness between the first film and the second film, it becomes easy to recognize which film is the touch or the appearance, and an operational error can be prevented.

The thickness of the first film is preferably 10 to 100 μm, more preferably 15 μm or more. In the case of 10 μm or more, after laminating the dry film on the base material, even if the first film is heat-treated without being peeled off, the first film is difficult to heat shrink, and the thickness is not uniform due to the heat shrinking, It is possible to prevent deterioration in quality such that the resin layer flows along the streaks generated in the first film due to the shrinkage, and the streaks are also generated in the resin layer.

When the resin layer of the dry film of the present invention is composed of a photosensitive resin composition, the first film is exposed to light such as the above thermoplastic resin so that the first dry film can be exposed without peeling. It is preferable to use a permeable material. In that case, the thickness of the first film is preferably 45 μm or less. When it is 45 μm or less, undercut is reduced. More preferably, it is 40 μm or less.

The dry film of the present invention can be preferably used for forming a permanent protective film of a printed wiring board, and can be preferably used for forming a solder resist layer, an interlayer insulating layer, and a cover lay of a flexible printed wiring board. Further, since the dry film of the present invention is excellent in embedding property, it can be suitably used for a printed wiring board having a fine circuit such as a package substrate having a large influence of bubbles, and particularly L / S = 10/10 μm or less. It can use suitably for the printed wiring board provided with the following fine circuit. Furthermore, the dry film of the present invention can also be suitably used when a vacuum laminate in which bubbles are likely to be generated is employed as the dry film laminating method. Moreover, since the cured product of the resin layer of the dry film of the present invention is excellent in forming a plating resist, it is preferably used for forming an interlayer insulating layer. You may form a wiring board by bonding a wiring together using the dry film of this invention. It can also be used as a sealing resin for semiconductor chips. It can also be used to form the outermost layer of the coreless substrate and the interlayer insulating layer.

Hereinafter, the present invention will be specifically described with reference to Examples, Comparative Examples and Test Examples of the present invention, but the present invention is not limited to the following Examples. In the following description, “parts” and “%” are all based on mass unless otherwise specified.

[Adjustment of surface-treated inorganic filler]
(Adjustment of surface-treated silicas A to D and adjustment of surface-treated aluminas A and B)
Into the flask, 100 g of each inorganic filler and 2000 g of an aqueous alcohol solution (water: alcohol = 1: 9 weight ratio) were added, and the mixture was stirred at room temperature at a rotation speed of 300 rpm for about 30 minutes to form a slurry. Next, 1 wt% of each silane coupling agent was prepared with respect to the weight of the inorganic filler, and slowly dropped into the slurry over 10 minutes so that the droplets did not scatter, and the slurry was stirred at 300 rpm for 10 minutes. Thereafter, circular qualitative filter paper was used to take out the surface-treated filler. Next, the surface-treated inorganic filler was spread on a shallow tray and dried at 110 ° C. for 60 minutes to obtain an inorganic filler surface-treated with a silane coupling agent. The inorganic filler and silane coupling agent used are described in the notes in Table 1 below.

(Examples 1 to 34 and Comparative Examples 1 to 12)
<Production of dry film>
Each component was blended according to the formulations shown in the Examples and Comparative Examples described in Tables 1, 3, 5, 7, 9, 11, 13 and 15 below, and dispersed in a roll mill, and the viscosity was 0.5 to 20 dPa · s (rotation). The curable resin composition was adjusted to have a viscometer of 5 rpm and 25 ° C. Next, using a bar coater, it was applied on a carrier film (Lumirror S10, thickness 38 μm, no surface treatment, Ra = 0.03 μm, manufactured by Toray Industries, Inc.) so that the film thickness of the dry film was 15 μm after drying. . Next, drying was performed at 85 ° C. for 5 to 15 minutes in a hot air circulation drying oven so that the residual solvent amount was 3.5 to 4.5%, and a curable resin layer was formed on the carrier film. Next, a protective film (MA-411, thickness 15 μm, Ra = 0.45 μm, manufactured by Oji F-Tech Co., Ltd.) was roll laminator on the dry coating surface at a set temperature of 70 ° C. to obtain a dry film having a three-layer structure.

<Storage elastic modulus G ′ and melt viscosity of resin layer>
For each dry film produced above, the protective film is peeled off, and the two dry film resin layers are stacked and thermocompression bonded with a one-chamber vacuum laminator MVLP-500 (manufactured by Meiki Co., Ltd.). The thickness of the layer was set to 350 μm. At that time, in order not to apply heat to the film, the temperature was 40 ° C., the pressure was 0.5 MPa, and the film was laminated for 1 minute, and the films were stacked. Next, the carrier film was peeled off using a viscosity / viscoelasticity measuring device Rheostress RS-6000 (manufactured by HAAKE), and then the temperature-viscoelasticity of each resin layer was measured. The measurement conditions were as follows: temperature increase mode 5 ° C./min, oscillation mode strain amount 8%, frequency 1 Hz, parallel plate of measurement sensor Φ20 mm, and gap 300 μm between sensors. By thickening the resin layer with respect to the gap, a sufficient resin thickness can be secured between the gaps even during heating. From the temperature-storage elastic modulus G ′ and viscosity η curves measured by the method as described above, the storage elastic modulus and melt viscosity at 100 ° C. are expressed as “resin layer storage elastic modulus G ′” and “resin layer It was referred to as “melt viscosity”. The measurement results are shown in the table.

<Embedment (bubble generation FLS (fine line &space))>
As a pretreatment on a double-sided printed wiring board in which a fine circuit of a comb-tooth pattern having a copper thickness of 10 μm, L (line: wiring width) / S (space: spacing width) = 5/5 μm, and an aspect ratio of 2.0 is formed, Etching treatment corresponding to 0.5 μm was performed by CZ-8101 treatment manufactured by MEC. Next, the dry film having a thickness of 15 μm prepared as described above was laminated on the substrate on which L / S was formed using a batch type vacuum pressure laminator MVLP-500 (manufactured by Meiki Co., Ltd.). Lamination was carried out under the conditions of 5 kgf / cm ² , 100 ° C., 1 minute, 1 Torr, and then leveled in the hot plate press step under the conditions of 10 kgf / cm ² , 100 ° C., 1 minute. After laminating, air entered the boundary between the line and the space, and whether or not bubbles were generated was confirmed after peeling the carrier film at 100 locations. What was evaluated by this method was defined as “after lamination”. Next, the evaluation of the presence or absence of generation of bubbles in the state where the resin layer was cured was regarded as “after curing”. The curing conditions are detailed in the next section. The evaluation criteria are as follows.
○: No void was confirmed.
Δ: 1 to 5 voids were confirmed.
X: Viscosity and elastic modulus were high and could not be embedded in a substrate having fine wires.

<Flatness of substrate after curing>
With respect to the resin layer of each dry film laminated on the substrate on which the fine circuit is formed by the method described in <Embeddability (Bubbling Generation FLS)>, the curing system is thermosetting, After the carrier film was peeled off, the resin layer was cured at 180 ° C. for 30 minutes in a hot air circulation drying oven and then at 200 ° C. for 60 minutes to completely cure the resin layer.
On the other hand, when the curing system is light / thermosetting, it is photocured at an exposure amount of 300 mJ / cm ² (i-line, Ushio projection exposure machine) so that the thin line portion is completely exposed from the carrier film. Then, the carrier film was peeled off. Subsequently, development was performed for 60 seconds at a 1 wt% sodium carbonate aqueous solution, a pressure of 0.2 MPa, and a liquid temperature of 30 ° C. Subsequently, 1000 mJ / cm < ² > exposure was performed with the high pressure mercury lamp irradiation apparatus. Thereafter, the resin layer was completely cured by heat curing at 180 ° C. for 60 minutes in a hot air circulation drying oven.
For the substrate completely cured by each curing method, the unevenness of the surface of the cured film perpendicular to the fine line was measured with a contact surface roughness measuring device (SE-300, manufactured by Kosaka Laboratory). The unevenness on the cured film was measured with a width of 20 mm. The evaluation criteria are as follows.
A: On a fine circuit, the unevenness has a maximum tolerance of less than 0.3 μm. At the same time, copper burn of the fine circuit was not observed.
○: On the fine circuit, the unevenness has a maximum tolerance of less than 0.3 μm.
Δ: Concavities and convexities are maximum and tolerance is 0.3 μm or more and less than 1.0 μm on a fine circuit.
×: On the fine circuit, the unevenness is maximum and the tolerance is 1.0 μm or more.
XX: Concavities and convexities are maximum and the tolerance is 5.0 μm or more on a fine circuit. The unevenness of the circuit was noticeable.

<Adhesion with underlying circuit>
Etching treatment corresponding to 0.5 μm was performed on the glossy surface of electrolytic copper foil GTS-MP-18 μm (manufactured by Furukawa Circuit Foil Co., Ltd.) by CZ-8101 treatment manufactured by MEC.
Thereafter, the respective dry films are laminated on the treated surface side by the method described in <embedding property (bubble generation FLS)>, and then the method of <flatness of substrate after curing> The resin layer was completely cured. After that, using a two-component adhesive araldite on the resin layer side, the 1.6 mm tFR-4 etch-out plate was laminated, the adhesive layer was cured at room temperature, and CZ-treated copper foil-resin layer-FR4 material 3 A layer structure was obtained. The obtained substrate was subjected to CZ treatment of each resin layer in accordance with the JIS-C-6481 copper-clad laminate test method and peel strength measurement method (test piece width 10 mm, 90 ° direction, speed 50 mm / min). The adhesive strength with the surface was measured. Judgment criteria are as follows.
A: Adhesive strength is 5.0 N / cm or more.
○: Adhesive strength is 3.0 N / cm or more and less than 5.0 N / cm.
X: Viscosity or elastic modulus was high, and an evaluation sample could not be prepared.

<Formability of plating resist>
The cured substrate produced by the method described in <Flatness of Substrate After Curing> was further evaluated by forming a plating resist on the surface thereof.
Specifically, the cured substrate thus produced was swelled at 60 ° C. for 5 minutes, permanganic acid at 80 ° C. for 20 minutes, and reduced at 50 ° C. at a permanganate desmear treatment (manufactured by Atotech, Securigant MV series for vertical desmear). The surface of the substrate was roughened by performing a partial treatment. Next, a copper seed layer having a thickness of 0.3 μm was formed on the surface of the substrate using an electroless copper plating process (manufactured by Uemura Kogyo Co., Ltd., alkali ion type Pd). Thereafter, the surface of the copper seed layer was degreased with alkali, and then a plating resist Fortec RY-3625 (manufactured by Hitachi Chemical Co., Ltd., SAP plating resist, thickness 25 μm) was used under a pressure condition of 110 ° C. and 0.4 MPa using a roll laminator. The substrates were bonded to each other. Subsequently, a glass dry plate negative mask L / S pattern (L / S = 10/10 μm pattern is formed in an area of 20 mm × 20 mm by EXP-2960 (manufactured by Oak Manufacturing Co., Ltd., parallel light exposure machine). Using a negative mask, a negative pattern was formed on the substrate surface with an exposure amount of 100 mJ / cm ² . Next, development was performed with a 1 wt% aqueous sodium carbonate solution at 30 ° C. for 30 seconds to form an L / S pattern on the substrate surface. About the obtained board | substrate, it observed using SEM. Extract 100 locations at random within the range of 20mm x 20mm, and evaluate the formation of plating resist (confirmation of the presence or absence of development defects due to lines flying or dents) It was. Judgment criteria are as follows.
○: Good formability.
Δ: L / S formation failure (line missing, development failure) was observed in one or more places and less than 10 places.
X: L / S formation failure (line missing, development failure) was observed at 10 or more locations.
XX: The pattern was not formed as designed because the ground was not flat.

<Dielectric loss tangent after humidification>
A dry film having a resin layer thickness of 15 μm prepared by the method described in <Preparation of Dry Film> is placed on the glossy surface of electrolytic copper foil GTS-MP-18 μm (Furukawa Circuit Foil Co., Ltd.). Lamination was performed by the method described in (FLS)>, and then the resin layer was completely cured by the method <Flatness of substrate after curing>. Thereafter, the cured product was peeled from the copper foil to obtain a cured product having a thickness of 15 μm.
The obtained cured product is stored in a high-temperature and high-humidity tank set at a temperature of 85 ° C. and a humidity of 85% RH for 100 hours, and within 10 minutes of removal, an SPDR dielectric resonator and a network analyzer (both manufactured by Agilent) The dielectric loss tangent at the time of humidification of 5.1 GHz at 23 ° C. was measured. Judgment criteria are as follows.
A: The dielectric loss tangent at 5 GHz is less than 0.005.
A: The dielectric loss tangent at 5 GHz is 0.005 or more and less than 0.01.
○: Dielectric loss tangent at 5 GHz is 0.01 or more and less than 0.015.
(Triangle | delta): The dielectric loss tangent in 5 GHz is 0.015 or more and less than 0.02.
X: The dielectric loss tangent at 5 GHz is 0.02 or more.

<Heat dissipation characteristics>
A cured product of 15 μm obtained by the same method as in <Dielectric loss tangent after humidification> was measured for the thermal conductivity of the cured product in accordance with the method described in JIS-R1611. Judgment criteria are as follows.
A: Thermal conductivity is 1 W / m · K or more.
○: Thermal conductivity is 0.3 W / m · K or more and less than 1 W / m · K.
Δ: Thermal conductivity is less than 0.3 W / m · K.
X: Viscosity or elastic modulus was high, and an evaluation sample could not be prepared.

<Coefficient of thermal expansion>
A 15 μm cured product obtained by the same method as in <Dielectric loss tangent after humidification> was peeled off from the copper foil, and then a sample was cut out to a measurement size (3 mm × 10 mm size) and supplied to TMA6100 manufactured by Seiko Instruments Inc. did. In the TMA measurement, the test weight was 5 g, and the sample was heated from room temperature at a heating rate of 10 ° C./min, and was measured twice continuously. Evaluation was made as the coefficient of thermal expansion (CTE (α1)) in the region of Tg or less in the second time. Judgment criteria are as follows.
A: CTE below glass transition temperature is less than 10 ppm.
(Double-circle): CTE below glass transition temperature is 10 ppm or more and less than 17 ppm.
○: CTE below glass transition temperature is 17 ppm or more and less than 30 ppm.
(Triangle | delta): CTE below a glass transition temperature is 30 ppm or more.
X: Viscosity or elastic modulus was high, and an evaluation sample could not be prepared.

<Board warpage>
On a copper clad laminate having a thickness of 200 μm and a size of 100 × 100 mm (MCL-E-770G, Hitachi Chemical Co., Ltd., copper thickness of 18 μm, pre-treated with etching equivalent to CZ-8101 1 μm) > Using a vacuum laminator to laminate a dry film with a resin thickness of 15 μm, prepared by the method described in>, and then peeling off the carrier film, and then completely curing the resin layer using a hot air circulating drying oven I let you. About the obtained board | substrate, the amount of curvature was measured using the caliper in four corners of the board | substrate, and evaluation was performed according to the following judgment criteria.
A: The maximum value of warpage is less than 3 mm.
○: The maximum value of warpage is 3 mm or more and less than 15 mm.
(Triangle | delta): The maximum value of curvature is 15 mm or more.
X: Viscosity or elastic modulus was high, and an evaluation sample could not be prepared.

<Reflow + TCT (Thermal Cycling Test)>
The dry film thickness (resin thickness 15 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.), 80 Lamination was performed at 1 ° C. for 1 minute at a temperature. Thereafter, the carrier film was peeled off and heated in a hot air circulation drying furnace, and the resin layer was cured at 180 ° C. for 30 minutes. 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.
When the curing system is light / thermosetting, exposure and development are performed using a negative pattern of Φ65 μm by the method described in <Flatness of Substrate After Curing>, and then UV irradiation and main curing are performed. And vias were formed.
Then, the obtained via pattern is processed 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 in order. Copper plating treatment was performed so as to fill the via thickness with a copper thickness of 25 μm. Subsequently, the test board | substrate which performed the thermosetting for 60 minutes at 200 degreeC with the hot-air circulation type drying furnace and performed the copper plating process which carried out complete hardening was obtained. The obtained test substrate was subjected to a reflow treatment three-cycle thermal shock under the lead-free assembly conditions (peak temperature: 270 ° C., 10 seconds), and then subjected to 30 minutes at −65 ° C. and 30 minutes at 150 ° C. for 1 minute. As a cycle, a cold cycle treatment was performed. After 2000 and 3000 cycles, in order to observe the state of the bottom and wall surface of the via with an optical microscope, the central portion of the via 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.
A: No cracks occurred after the end of 3000 cycles.
○: No crack occurred after 2000 cycles. 1 to 5 cracks occurred in 3000 cycles.
Δ: 1 to 5 cracks occurred after 2000 cycles.
X: The test piece could not be produced because the melt viscosity and the storage elastic modulus exceeded the optimum range.

<Relative permittivity>
A dry film having a resin layer thickness of 15 μm prepared by the method described in <Preparation of Dry Film> is placed on the glossy surface of electrolytic copper foil GTS-MP-18 μm (Furukawa Circuit Foil Co., Ltd.). Lamination was performed by the method described in (FLS)>, and then the resin layer was completely cured by the method <Flatness of substrate after curing>. Thereafter, the cured product was peeled from the copper foil to obtain a cured product having a thickness of 15 μm.
About the obtained hardened | cured material, the specific dielectric constant of 1 GHz in 23 degreeC was measured using the SPDR dielectric resonator and the network analyzer (both manufactured by Agilent). Judgment criteria are as follows.
A: Dielectric constant at 1 GHz is 10.0 or more.
○: The relative dielectric constant at 1 GHz is 5.0 or more and less than 10.0.

<Circuit concealment>
A cured film was formed on the fine circuit board by the methods described in the above <Embedment property (bubble generation FLS)> and <Flatness of substrate after curing>, and then the carrier film was peeled off to obtain a printed wiring board.
About the obtained evaluation board | substrate, the discoloration of the copper circuit from a cured film was confirmed visually, and the concealability of the circuit was evaluated. Judgment criteria are as follows.
A: Discoloration is not confirmed.
X: Discoloration was confirmed.

* 1: HP-820 manufactured by DIC, alkylphenol type liquid epoxy resin, epoxy equivalent: 225 g / eq
* 2: Nippon Kayaku NC-3000L, biphenyl aralkyl type solid epoxy resin, epoxy equivalent: 275 g / eq
* 3: CG-500 manufactured by Osaka Gas Chemical Company, fluorene-based solid epoxy resin, epoxy equivalent: 311 g / eq
* 4: Nissan Chemical Co., Ltd. TGIC, triglycidyl isocyanurate (solid epoxy resin), epoxy equivalent: 99 g / eq
* 5: Mitsubishi Chemical 1003, Bis-A type solid epoxy resin, epoxy equivalent: 720 g / eq
* 6: TD-2131 manufactured by DIC, phenol novolac resin, hydroxyl group equivalent: 104 g / eq
* 7: MEH-7851-4H manufactured by Meiwa Kasei Co., Ltd., biphenyl aralkyl type phenol resin, hydroxyl group equivalent: 240 g / eq
* 8: DIC LA-3018, ATN-containing phenol novolac resin, hydroxyl equivalent: 151 g / eq
* 9: Maruka Linker M manufactured by Maruzen Chemical Co., polyvinylphenol, hydroxyl group equivalent of 120 g / eq
* 10: PT-30 manufactured by Lonza Japan, novolak-type cyanate ester resin, cyanate equivalent: 124 g / eq
* 11: BA-3000 manufactured by Lonza Japan, Bis-A type cyanate ester resin, cyanate equivalent: 284 g / eq
* 12: Yamato Kasei Kogyo BMI-1100, N, N′-diphenylmethane bismaleimide, maleimide equivalent: 179 g / eq
* 13: MIR-3000 manufactured by Nippon Kayaku Co., Ltd., biphenyl skeleton-containing bismaleimide, maleimide equivalent: 275 g / eq
* 14: PC-1100-02 manufactured by Air Water, polyfunctional active ester resin, active ester equivalent: 154 g / eq
* 15: EXB9416 manufactured by DIC, naphthol end, dicyclopentadiene skeleton-containing active ester resin, active ester equivalent: 220 g / eq
* 16: RMA-11902 manufactured by Nippon Emulsifier Co., Ltd., photosensitive carboxyl group-containing resin having acrylic group starting from phenol resin (solid content: 65%)
* 17: Shin-Nakamura Chemical Co., Ltd. A-DCP, dicyclopentadiene skeleton acrylic monomer * 18: Toa Gosei HPS-500, D50 = 0.5 μm spherical silica * 19: Toa Gosei HPS-1000 D50 = Spherical silica of 1.0 μm * 20: Surface-treated silica A prepared as above (Nanosilica manufactured by Admatechs (average primary particle size (D50) = 50 nm) treated with 1 wt% aminosilane)
* 21: FB-5SDX, manufactured by Denki Kagaku Kogyo Co., Ltd., D50 = 4.9 μm spherical silica * 22: Surface-treated silica B prepared above (HPS-500 / KBE-1003, HPS-500 treated with 1 wt% vinyl silane) Product)
* 23: Surface-treated silica C prepared as described above (HPS-500 / KBE-9103, HPS-500 treated with 1 wt% aminosilane)
* 24: Surface-treated silica D prepared as described above (HPS-1000 / KBE-1003, HPS-1000 treated with 1 wt% vinyl silane)
* 25: Surface-treated silica E prepared as described above (FB-5SDX / KBE-9103, FB-5SDX treated with 1 wt% aminosilane)
* 26: ASFP-20 manufactured by Denki Kagaku Kogyo Co., Ltd., D50 = 0.3 μm spherical alumina * 27: DAM-03 manufactured by Denki Kagaku Kogyo Co., Ltd., D50 = 3.7 μm spherical alumina * 28: Surface treatment adjusted as above. Alumina A (ASFP-20 / KBE-1003, 1% by weight vinyl silane treated product of ASFP-20)
* 29: Surface-treated alumina B prepared as described above (DAM-03 / KBE-1003, DAM-03 treated with 1 wt% vinyl silane)
* 30: Fuselex WX manufactured by Tatsumori, D50 = 1.5 μm amorphous silica * 31: KBE-1003 manufactured by Shin-Etsu Chemical, vinyltriethoxysilane * 32: KBE-402, 3-glycid manufactured by Shin-Etsu Chemical Xylpropylmethyldiethoxysilane * 33: Shin-Etsu Chemical KBE-9103, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine * 34: BASF Japan Irgacure 369, α-aminoalkyl Phenone photopolymerization initiator * 35: 1% by weight of cobalt acetylacetonate, DMF solution * 36: 2E4MZ-AP manufactured by Shikoku Kasei Co., Ltd., imidazole * 37: YL7600 manufactured by Mitsubishi Chemical Co., Ltd., phenoxy resin containing low dielectric skeleton * 38: Cyclohexanone * 39: DMF (N, N-dimethylformamide)
* 40: Ipsol 100, Idemitsu Kosan Co., Ltd., aromatic high boiling point solvent

* 42: EPICLON 860 manufactured by DIC, bisphenol A type semi-solid epoxy resin, epoxy equivalent: 245 g / eq
* 43: DIC's HP-4032, naphthalene type semi-solid epoxy resin, epoxy equivalent: 150 g / eq
* 44: N-740 manufactured by DIC, phenol novolac semi-solid epoxy resin, epoxy equivalent: 180 g / eq

* 45: BT-03B manufactured by Sakai Chemical Industry D50 = 0.3μm

* 46: Ishihara Sangyo Typepek CR-97 D50 = 0.25μm
* 47: Sakai Chemical Industry CZ-03 D50 = 0.3 μm

* 48: Cannot be laminated

From the results shown in the above table, it can be seen that the dry films of Examples 1 to 34 are excellent in the embedding property and flatness of the resin layer. On the other hand, the dry film of Comparative Examples 1 to 11 in which the melt viscosity of the resin layer does not satisfy 60 to 5500 dPa · s at 100 ° C., or the storage elastic modulus of the resin layer does not satisfy 80 to 5500 Pa at 100 ° C., and the resin layer The dry film of Comparative Example 12 having a liquid epoxy resin content of 60% by mass or more was inferior in embedding property and flatness.

DESCRIPTION OF SYMBOLS 11 Two-layer dry film 12 Resin layer 13 Film 21 Three-layer dry film 22 Resin layer 23 First film 24 Second film 30a Test tube 30b for liquid determination Temperature test tube 31 Mark (A line )
32 Mark (B line)
33a, 33b Rubber stopper 34 Thermometer

Claims

A dry film having a film and a resin layer containing an epoxy resin formed on the film,
The resin layer has a melt viscosity of 60 to 5500 dPa · s at 100 ° C.,
The storage elastic modulus of the resin layer is 80 to 5500 Pa at 100 ° C.,
The resin layer includes at least a liquid epoxy resin as the epoxy resin,
Content of the said liquid epoxy resin is less than 60 mass% per said epoxy resin total mass, The dry film characterized by the above-mentioned.
The dry film according to claim 1, wherein the amount of residual solvent in the resin layer is 1.0 to 7.0% by mass.
The resin layer contains at least two organic solvents selected from the group consisting of N, N-dimethylformamide, toluene, cyclohexanone, aromatic hydrocarbons having 8 or more carbon atoms, and methyl ethyl ketone. 1. The dry film according to 1.
The resin layer further includes at least one semi-solid epoxy resin selected from the group consisting of a bisphenol A type epoxy resin, a naphthalene type epoxy resin, and a phenol novolac type epoxy resin as the epoxy resin. Item 2. The dry film according to Item 1.
The resin layer includes a filler,
2. The dry film according to claim 1, wherein the filler has an average particle size of 0.1 to 10 μm.
The resin layer includes a filler,
The dry film according to claim 1, wherein the blending amount of the filler is 40 to 80% by mass based on the total amount of the resin layer (the total amount excluding the solvent when the resin layer includes a solvent).
The resin layer includes a filler,
The filler is an epoxy group-containing silane coupling agent, an amino group-containing silane coupling agent, a mercapto group-containing silane coupling agent, an isocyanate group-containing silane coupling agent, a vinyl group-containing silane coupling agent, or styryl. The dry film according to claim 1, which is surface-treated with at least one of a silane coupling agent having a group, a silane coupling agent having a methacryl group, and a silane coupling agent having an acrylic group.
A cured product obtained by curing the resin layer of the dry film according to any one of claims 1 to 7.
A printed wiring board comprising the cured product according to claim 8.