JP6767154B2 - Dry film, hardened material and printed wiring board - Google Patents

Description

The present invention relates to dry films, cured products and printed wiring boards.

Conventionally, a dry film (laminated 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, 2) In recent years, with the thinning of substrates and the miniaturization of circuits, there is an increasing demand for dry films for forming protective films such as solder resists and insulating layers. The dry film has a resin layer obtained by applying a resin composition having desired properties on the support film and then performing a drying step, and generally for protecting the surface opposite to the support film. Protective film is further laminated and is distributed on the market. A protective film or an insulating layer as described above can be formed on a printed wiring board by applying a resin layer of a dry film to a substrate (hereinafter, also referred to as “laminate”) and then performing a patterning or curing treatment.

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

When laminating the protective film on the resin layer, there is a problem that the protective film floats or peels off.

In addition, the resin layer may accidentally adhere to the base material during manual work or transportation, and in that case, it is required that the resin layer can be peeled off and reworked, but the resin layer is based at room temperature. There was a problem that rework was difficult because it stuck to the material.

Further, the resin layer is required to be smooth, that is, even if the resin layer is laminated on a substrate having unevenness, the surface of the resin layer is required to be smooth without becoming uneven.

Therefore, an object of the present invention is to obtain a dry film having a resin layer excellent in reworkability and smoothness without floating or peeling of the protective film, a cured product obtained by curing the resin layer of the dry film, and the cured product. The purpose is to provide a printed wiring board to be provided.

As a result of diligent studies in view of the above, the present inventors have found that a film (in many cases, a protective film) provided on the surface side of the resin layer that comes into contact with the base material when laminated on the base material, that is, the laminated surface side. adjust the roughness of the surface in contact with the resin layer, and, by blending the surface-treated inorganic filler in the resin layer containing an epoxy resin, ⁴ melt viscosity 1.0 × 10 at 50 ° C. of the resin layer to 1 We have found that the above-mentioned problems can be solved by setting the value to 0.0 × 10 ⁶ dPa · s, and have completed the present invention.

That is, the dry film of the present invention is a carboxyl group-containing resin, an epoxy resin, and a surface treatment sandwiched between the first film, the second film, the first film, and the second film. A dry film having a resin layer containing the above-mentioned inorganic filler, wherein the melt viscosity of the resin layer at 50 ° C. is 1.0 × 10 ^{4 to} 1.0 × 10 ⁶ dPa · s, and the second A dry film characterized in that the arithmetic average surface roughness Ra of the surface of the film in contact with the resin layer is 0.1 μm or more, and the surface of the resin layer in contact with the second film is a laminated surface on the substrate. Is.

In the dry film of the present invention, the minimum melt viscosity of the resin layer at 90 to 120 ° C. is preferably 50 to 900 dPa · s.

In the dry film of the present invention, it is preferable that the resin layer does not contain an inorganic filler having a decomposition temperature of less than 250 ° C.

In the dry film of the present invention, it is preferable that the resin layer contains a non-silicone release agent.

The dry film of the present invention is preferably for forming a solder resist.

The cured product of the present invention is characterized by being 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, a dry film having a resin layer excellent in reworkability and smoothness without floating or peeling of the protective film, a cured product obtained by curing the resin layer of the dry film, and the cured product are provided. A printed wiring board can be provided.

It is the schematic sectional drawing which showed one Embodiment of the dry film of this invention.

<Dry film>
In the dry film of the present invention, the arithmetic mean surface roughness Ra of the surface of the second film in contact with the resin layer is 0.1 μm or more, and the surface of the resin layer in contact with the second film is the base material. It is a laminated surface to. By defining the roughness of the surface of the second film in the range, unevenness is also formed on the surface of the resin layer in contact with the surface. The arithmetic average surface roughness Ra of the surface of the second film in contact with the resin layer is preferably 0.1 to 1.2 μm, more preferably 0.1 to 0.8 μm. The arithmetic mean surface roughness Ra means a value measured in accordance with JIS B0601. Further, in the dry film of the present invention, when the protective film is attached to the resin layer containing the carboxyl group-containing resin and the epoxy resin, the second film is easy to attach and the reaction between the carboxyl group and the epoxy group is suppressed. The temperature at which the resin layer is attached to the resin layer, that is, the temperature at which the unevenness of the protective film comes into contact with the surface of the resin layer is preferably 40 to 60 ° C., and the resin layer is melted at 50 ° C. By adding a surface-treated inorganic filler to the resin layer with a viscosity of 1.0 × 10 ^{4 to} 1.0 × 10 ⁶ dPa · s, excellent protection is provided on the surface of the resin layer on which irregularities are formed. It is possible to obtain the adhesiveness, reworkability and smoothness of the film. Melt viscosity at 50 ° C. of the resin layer is preferably ^{1.0 × 10 4 ~7.0 × 10 5} dPa · s. Further, the minimum value of the melt viscosity of the resin layer at 90 to 120 ° C. is preferably 50 to 900 dPa · s. When it is 50 to 900 dPa · s, the balance of smoothness is excellent.

FIG. 1 is a schematic cross-sectional view showing an embodiment of the dry film of the present invention. The dry film 1 has a first film 11, a second film 12, and a resin layer 13 sandwiched between the first film 11 and the second film 12. The surface of the second film in contact with the resin layer is rough and has an arithmetic average surface roughness Ra of 0.1 μm or more.

[First film and second film]
When laminating a dry film having a resin layer sandwiched between a support 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, in some cases, the support film is peeled off and laminated so that the surface of the resin layer on the side in contact with the support film comes into contact with the base material. In the present invention, the surface of the film (that is, the second film) peeled off from the resin layer when the resin layer is laminated on the base material in contact with the resin layer has an arithmetic mean surface roughness Ra in the above range. You just have to do it. That is, the second film may be either a support film or a protective film. Preferably, the first film is the support film and the second film is the protective film.

The support film has a role of supporting the resin layer of the dry film, and is a film to which the curable resin composition described later is applied when the resin layer is formed. Examples of the support film include polyester films such as polyethylene terephthalate and polyethylene naphthalate, polyimide films, polyamideimide films, polyethylene films, polytetrafluoroethylene films, polypropylene films, and films made of thermoplastic resins such as polystyrene films. Surface-treated paper or the like can be used. Among these, a polyester film can be preferably used from the viewpoint of heat resistance, mechanical strength, handleability and the like. The thickness of the support film is not particularly limited, but is appropriately selected in the range of approximately 10 to 150 μm according to the application. The surface of the support film on which the resin layer is provided may be subjected to a mold release treatment. Further, sputtered or ultrathin copper foil may be formed on the surface of the support film on which the resin layer is provided.

The protective film is provided on the surface opposite to the support 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 handleability. As the protective film, for example, a film made of the thermoplastic resin exemplified in the support film, surface-treated paper and the like can be used, and 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 in the range of approximately 10 to 150 μm according to the application. The surface of the protective film on which the resin layer is provided may be subjected to a mold release treatment.

When a thermoplastic resin film is used as the second film having the arithmetic average surface roughness Ra as described above, a filler may be added to the resin when the film is formed, or the film surface may be blasted. Alternatively, the surface can be formed into a predetermined shape by hairline processing, matte coating, chemical etching, or the like, and a thermoplastic resin film having the above-mentioned arithmetic average surface roughness Ra can be obtained. For example, when the filler is added to the resin, the arithmetic mean surface roughness Ra can be controlled by adjusting the particle size and the amount of the filler added. Further, in the case of blasting, the arithmetic mean surface roughness Ra can be controlled by adjusting the processing conditions such as the blasting material and the blasting pressure. As the thermoplastic resin film having such a surface roughness, a commercially available one may be used. For example, Toray Industries, Inc. Lumirror X42, Lumirror X43, Lumirror X44, Unitika Ltd. Emblet PTH-12, Emblet PTH. -25, Embret PTHA-25, Embret PTH-38, Alfan MA-411, MA-420, E-201F and ER-440 manufactured by Oji F-Tex Co., Ltd. can be mentioned.

The thickness of the first film is preferably 10 to 100 μm, more preferably 15 μm or more. When the thickness is 10 μm or more, even if the dry film is laminated on the base material and then heat-treated without peeling the first film, the first film does not easily shrink due to heat shrinkage, and the thickness becomes uneven due to heat shrinkage or heat. It is possible to prevent quality deterioration such that the resin layer flows along the streaks generated in the first film due to the shrinkage and streaks are also generated in the resin layer.

[Resin layer]
The resin layer of the dry film of the present invention is obtained through a drying step after applying the resin composition to the first film or the second film. The resin composition is not particularly limited, and a resin composition used for forming a protective layer or an insulating layer provided on a printed wiring board such as a solder resist, an interlayer insulating layer and a coverlay can be used. The film thickness of the resin layer is not particularly limited, but the film thickness after drying is preferably 1 to 200 μm. In the case of a photocurable resin layer, when it is 200 μm or less, it is possible to suppress a decrease in deep curability. Specific examples of the resin composition include a photocurable resin composition containing a photopolymerization initiator, a photocurable thermosetting resin composition, a photocurable resin composition containing a photobase generator, and a negative photocuring agent. Photocurable resin compositions such as sex resin compositions, alkali-developed photocurable resin compositions, solvent-developed photocurable resin compositions, thermosetting resin compositions, swelling peeling type resin compositions, dissolution peeling type Examples thereof include, but are not limited to, resin compositions. Of these, a curable resin composition is preferable.

[Carboxylic group-containing resin]
From the viewpoint of photocurability and development resistance, the carboxyl group-containing resin may have an ethylenically unsaturated bond in the molecule in addition to the carboxyl group, and may have a carboxyl group that does not have an ethylenically unsaturated double bond. It may be a contained resin. The ethylenically unsaturated double bond is preferably derived from (meth) acrylic acid or a derivative thereof. As the carboxyl group-containing resin, one type can be used alone or two or more types can be used in combination.

Specific examples of the carboxyl group-containing resin include compounds (either oligomers and polymers) listed below.

(1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth) acrylic acid with an unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, or isobutylene.

(2) 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-based polyols and polyether-based compounds. A carboxyl group-containing urethane resin obtained by a double addition 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, and a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(3) Aliphatic compounds such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates, and polycarbonate-based polyols, polyether-based polyols, polyester-based polyols, polyolefin-based polyols, acrylic-based polyols, and bisphenol A-based A terminal carboxyl group-containing urethane resin obtained by reacting an acid anhydride at the end of a urethane resin by a double addition reaction of a diol compound such as an alkylene oxide adduct diol, a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(4) 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 ( Meta) A carboxyl group-containing urethane resin obtained by a double addition reaction of an acrylate or a modified partial acid anhydride thereof, a carboxyl group-containing dialcohol compound and a diol compound.

(5) During the synthesis of the resin of (2) or (4) above, a compound having one hydroxyl group and one or more (meth) acryloyl groups is added to the molecule such as hydroxyalkyl (meth) acrylate, and the terminal (5) Meta) Acryloylated carboxyl group-containing urethane resin.

(6) During the synthesis of the resin according to (2) or (4) above, one isocyanate group and one or more (meth) acryloyl groups are added to the molecule, such as an isophorone diisocyanate and pentaerythritol triacrylate equimolar reaction product. A carboxyl group-containing urethane resin that is terminal (meth) acrylicized by adding the compound to be possessed.

(7) A carboxyl group obtained by reacting a polyfunctional epoxy resin with (meth) acrylic acid and adding a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, or hexahydrophthalic anhydride to a hydroxyl group existing in a side chain. Containing resin.

(8) A carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl groups of a bifunctional epoxy resin with epichlorohydrin with (meth) acrylic acid and adding a dibasic acid anhydride to the generated hydroxyl groups. ..

(9) A carboxyl group-containing polyester resin obtained by reacting a polyfunctional oxetane resin with a dicarboxylic acid and adding a dibasic acid anhydride to the generated primary hydroxyl group.

(10) Reaction production obtained by reacting 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 with an unsaturated group-containing monocarboxylic acid. A carboxyl group-containing resin obtained by reacting a compound with a polybasic acid anhydride.

(11) Obtained by reacting an unsaturated group-containing monocarboxylic acid 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. A carboxyl group-containing resin obtained by reacting a reaction product with a polybasic acid anhydride.

(12) 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 (meth). Reacting with an unsaturated group-containing monocarboxylic acid such as acrylic acid, maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, anhydrous with respect to the alcoholic hydroxyl group of the obtained reaction product. A carboxyl group-containing resin obtained by reacting a polybasic anhydride such as adipic acid.

(13) In addition to the carboxyl group-containing resins described in (1) to (12) above, one epoxy group and one or more (meth) acrylates in molecules such as glycidyl (meth) acrylate and α-methylglycidyl (meth) acrylate. Meta) A carboxyl group-containing resin obtained by adding a compound having an acryloyl group.

Among the above carboxyl group-containing resins, the carboxyl group-containing resins described in (1), (7), (8), and (10) to (13) are preferable.

The acid value of the carboxyl group-containing resin is preferably in the range of 20 to 200 mgKOH / g, more preferably in the range of 40 to 180 mgKOH / g. When it is in the range of 20 to 200 mgKOH / g, the peelability and printability of the dried coating film with an alkaline aqueous solution are improved, and dripping is unlikely to occur during drying. Since the carboxyl group-containing resin has a large number of carboxyl groups in the side chain of the backbone polymer, it can be developed with a dilute alkaline aqueous solution.

The weight average molecular weight of the carboxyl group-containing resin varies depending on the resin skeleton, but is preferably in the range of 2,000 to 150,000. Within this range, the tack-free performance is good, the moisture resistance of the coating film after exposure is good, and film loss is unlikely to occur during development. Further, when the weight average molecular weight is in the range, the printability and the heat resistance of the cured film are improved. More preferably, it is 5,000 to 100,000. The weight average molecular weight can be measured by gel permeation chromatography.

[Epoxy resin]
The resin layer contains an epoxy resin. As the epoxy resin, a known and commonly used compound having one or more epoxy groups can be used, and among them, a compound having two or more epoxy groups is preferable. For example, monoepoxy compounds such as monoepoxy compounds such as butyl glycidyl ether, phenylglycidyl ether, and glycidyl (meth) acrylate, bisphenol A type epoxy resin, bisphenol S type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, Cresol novolac type epoxy resin, alicyclic epoxy resin, trisphenol methane type epoxy resin, trimethylolpropane polyglycidyl ether, phenyl-1,3-diglycidyl ether, biphenyl-4,4'-diglycidyl ether, 1,6 -In one molecule of hexanediol diglycidyl ether, diglycidyl ether of ethylene glycol or propylene glycol, sorbitol polyglycidyl ether, tris (2,3-epoxypropyl) isocyanurate, triglycidyltris (2-hydroxyethyl) isocyanurate, etc. Examples include compounds having two or more epoxy groups. These can be used alone or in combination of two or more, depending on the required characteristics.

Specific examples of the compound having two or more epoxy groups include jER828, jER834, jER1001, jER1004 manufactured by Mitsubishi Chemical Corporation, Epicron 840, Epicron 850, Epicron 1050, Epicron 2055 manufactured by DIC Corporation, and Nippon Steel & Sumikin Chemical Co., Ltd. Epoxy YD-011, YD-013, YD-127, YD-128, Dow Chemical Japan Co., Ltd. E. R. 317, D.I. E. R. 331, D. E. R. 661, D.I. E. R. 664, Sumitomo Chemical Co., Ltd. Sumi-Epoxy ESA-011, ESA-014, ELA-115, ELA-128, Asahi Kasei E-Materials Co., Ltd. E. R. 330, A. E. R. 331, A. E. R. 661, A. E. R. Bisphenol A type epoxy resin such as 664; jERYL903 manufactured by Mitsubishi Chemical Corporation, Epicron 152 and Epicron 165 manufactured by DIC, Epototo YDB-400, YDB-500 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., D.D. E. R. 542, Sumitomo Chemical's Sumi-Epoxy ESB-400, ESB-700, Asahi Kasei E-Materials' A.M. E. R. 711, A. E. R. Brominated epoxy resin such as 714; jER152, jER154 manufactured by Mitsubishi Chemical Corporation, D.D. E. N. 431, D.I. E. N. 438, Epicron N-730, Epicron N-770, Epicron N-865 manufactured by DIC, Epototo YDCN-701, YDCN-704 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., EPPN-201, EOCN-1025 manufactured by Nippon Kayaku Co., Ltd. EOCN-1020, EOCN-104S, RE-306, NC-3000, Sumitomo Chemical's Sumi-Epoxy ESCN-195X, ESCN-220, Asahi Kasei E-Materials' A.M. E. R. ECN-235, ECN-299, YDCN-700-2, YDCN-700-3, YDCN-700-5, YDCN-700-7, YDCN-700-10, YDCN-704 YDCN-704A manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. , Novolak type epoxy resin such as Epicron N-680, N-690, N-695 (all trade names) manufactured by DIC; Epicron 830 manufactured by DIC, jER807 manufactured by Mitsubishi Chemical Co., Ltd., Epototo manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Bisphenol F type epoxy resin such as YDF-170, YDF-175, YDF-2004; Hydrogenated bisphenol A type epoxy resin such as Epototo ST-2004, ST-2007, ST-3000 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd .; JER604 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Epototo YH-434 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd .; Glycidylamine type epoxy resin such as Sumi-epoxy ELM-120 manufactured by Sumitomo Chemical Co., Ltd.; Hydant-in type epoxy resin; Epoxy resin; YL-933 manufactured by Mitsubishi Chemical Co., Ltd., T.D. manufactured by Dow Chemical Japan Co., Ltd. E. N. , EPPN-501, EPPN-502 and the like trihydroxyphenylmethane type epoxy resin; Mitsubishi Chemical Co., Ltd. YL-6056, YX-4000, YL-6121 and the like bixilenol type or biphenol type epoxy resin or a mixture thereof; Bisphenol S type epoxy resin such as EBPS-200 manufactured by Kayakusha, EPX-30 manufactured by ADEKA, EXA-1514 manufactured by DIC; Bisphenol A novolac type epoxy resin such as jER157S manufactured by Mitsubishi Chemical Co., Ltd .; Tetraphenylol ethane type epoxy resin such as jERYL-931; heterocyclic epoxy resin such as TEPIC manufactured by Nissan Chemical Industries; diglycidyl phthalate resin such as Blemmer DGT manufactured by Nikko Co., Ltd .; ZX-1063 manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd. Tetraglycidyl xylenoyl ethane resin; Naphthalene group-containing epoxy resin such as ESN-190, ESN-360, DIC HP-4032, EXA-4750, EXA-4700 manufactured by Nippon Steel & Sumitomo Metal Corporation; HP-7200 manufactured by DIC , HP-7200H and other epoxy resins having a dicyclopentadiene skeleton; glycidyl methacrylate copolymerized epoxy resins such as CP-50S and CP-50M manufactured by Nichiyu Co., Ltd .; and cyclohexyl maleimide and glycidyl methacrylate copolymer epoxy resins; CTBN-modified epoxy resins (for example, YR-102, YR-450 manufactured by Nippon Steel & Sumitomo Metal Corporation); trisphenol methane type epoxy resins and the like can be mentioned, but are not limited thereto. Among these, bisphenol A type epoxy resin, heterocyclic epoxy resin or a mixture thereof is particularly preferable because it is excellent in discoloration resistance. One of these epoxy resins may be used alone, or two or more of these epoxy resins may be used in combination.

The amount of the epoxy resin to be blended is such that the ratio of the epoxy group of the epoxy resin to the carboxyl group in the carboxyl group-containing resin is carboxyl group / epoxy group (equivalent ratio) = 0.2 to 3. Is preferable. Within the above range, the balance between the stability and curability of the resin layer is excellent.

[Surface-treated inorganic filler]
The resin layer contains a surface-treated inorganic filler. Here, the surface treatment of the inorganic filler refers to a treatment for improving compatibility with a resin component such as a carboxyl group-containing resin or an epoxy resin. The surface treatment of the inorganic filler is preferably a surface treatment capable of introducing a curable reactive group into the surface of the inorganic filler.

The inorganic filler is not particularly limited, and known and commonly used fillers such as silica, crystalline silica, Neuburg silica soil, aluminum hydroxide, glass powder, talc, clay, magnesium carbonate, calcium carbonate, natural mica, synthetic mica, and the like. Inorganic fillers such as aluminum hydroxide, barium sulfate, barium titanate, iron oxide, non-fibrous glass, hydrotalcite, mineral wool, aluminum silicate, calcium silicate, and zinc flower can be used. Of these, silica, barium sulfate, and talc are preferable, and spherical silica is more preferable because it has a small surface area and stress is less likely to be a starting point of cracks because it is dispersed throughout.

When the dry film of the present invention is used for a package substrate, it can be processed at a high temperature of 250 ° C. or higher, and therefore it is preferable not to contain an inorganic filler having a decomposition temperature of less than 250 ° C. The decomposition temperature of the inorganic filler can be measured using, for example, TG / DTA6200 manufactured by Hitachi High-Tech Science Corporation.
As an inorganic filler having a decomposition temperature of less than 250 ° C., for example, aluminum hydroxide is known. In the present specification, the decomposition temperature is a temperature at which the DTA curve begins to decrease, and aluminum hydroxide starts decomposition at about 210 ° C., and a weight loss of about 10% occurs at 250 ° C. As the measurement conditions, the temperature rise rate from room temperature to 100 ° C. is 5 ° C./min, the temperature rise rate is maintained at 100 ° C./30 min, and the temperature rise rate from 100 ° C. to 500 ° C. is 5 ° C./min.

The surface-treated inorganic filler may or may not have a curable reactive group that reacts with the curable resin on the surface. In the present specification, the curable reactive group is not particularly limited as long as it is a group that cures with a curable resin, and may be a thermosetting reactive group or a photocurable reactive group. Examples of the photocurable reactive group include a methacryl group, an acrylic group, a vinyl group, a styryl group and the like, and examples of the thermosetting reactive group include an epoxy group, an amino group, a hydroxyl group, a carboxyl group, an isocyanate group, an imino group and an oxetanyl. Examples thereof include a group, a mercapto group, a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group, an oxazoline group and the like. The surface-treated inorganic filler preferably has at least one of a methacryl group, an acrylic group, a vinyl group, an epoxy group, an amino group, an isocyanate group and a mercapto group as a curable reactive group. In addition, the inorganic filler may have two or more types of curable reactive groups.

The method for introducing the curable reactive group onto the surface of the inorganic filler is not particularly limited, and the curable reactive group may be introduced by using a known and commonly used method. A surface treatment agent having a curable reactive group, for example, a cup having a curable reactive group The surface of the inorganic filler may be treated with a ring agent or the like.

As the surface treatment of the inorganic filler, 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 and the like can be used. Of these, a silane coupling agent is preferable.

As the silane coupling agent, a silane coupling agent capable of introducing a curing reactive group into the inorganic filler is preferable. Examples of the silane coupling agent into which a thermosetting reactive group can be introduced include 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 a silane coupling agent having an isocyanate group. Examples thereof include a silane coupling agent having an epoxy group and a silane coupling agent having an amino group. Examples of the silane coupling agent into which a photocurable reactive group can be introduced include a silane coupling agent having a vinyl group, a silane coupling agent having a styryl group, a silane coupling agent having a methacryl group, and a silane coupling agent having an acrylic group. The agent is preferable, and the silane coupling agent having a methacryl group is more preferable.

Examples of the surface-treated inorganic filler having no curable reactive group include silica-alumina surface treatment, titanate-based coupling agent treatment, aluminate-based coupling agent treatment, and organically treated inorganic filler. Can be mentioned.

The surface-treated inorganic filler may be blended in the resin layer in a surface-treated state, and the surface-treated inorganic filler and the surface-treating agent are separately blended so that the inorganic filler is surfaced in the composition. Although it may be treated, it is preferable to add an inorganic filler that has been surface-treated in advance. By blending the inorganic filler that has been surface-treated in advance, it is possible to prevent deterioration of crack resistance and the like due to the surface-treating agent that may remain when the inorganic filler is blended separately and is not consumed in the surface treatment. In the case of surface treatment in advance, it is preferable to mix a pre-dispersion solution in which the surface-treated inorganic filler is pre-dispersed in the solvent, and the surface-treated inorganic filler is pre-dispersed in the solvent and the pre-dispersion solution is used as a composition. It is more preferable to form a resin layer by blending or after sufficient surface treatment when the surface-untreated inorganic filler is pre-dispersed in a solvent, the pre-dispersion liquid is blended with the composition.

The inorganic filler preferably has an average particle size of 2 μm or less because it is more excellent in smoothness after lamination. More preferably, it is 1 μm or less.

The blending amount of the surface-treated inorganic filler is preferably 20 to 80% by mass, more preferably 30 to 80% by mass, and further preferably 35 to 80% by mass, based on the total amount of the resin layer. preferable.

The surface-treated inorganic filler and the non-surface-treated inorganic filler may be used in combination. In that case, the surface-treated inorganic filler is preferably 30% by mass or more, more preferably 50% by mass or more, based on the total amount of the surface-treated inorganic filler and the non-surface-treated inorganic filler. It is more preferably 70% by mass or more.

(Curable resin)
The resin layer may contain a curable resin in addition to the carboxyl group-containing resin and the epoxy resin. The curable resin may be a thermosetting resin or a photocurable resin. Further, the curable resin may be used alone or in combination of two or more.

The thermosetting resin may be any resin that is cured by heating and exhibits electrical insulating properties, and examples thereof include oxetane compounds, melamine resins, and silicone resins.

（式中、Ｒ^１は、水素原子または炭素数１〜６のアルキル基を示す）により表されるオキセタン環を含有するオキセタン化合物の具体例として、３−エチル−３−ヒドロキシメチルオキセタン（東亞合成社製ＯＸＴ−１０１）、３−エチル−３−（フェノキシメチル）オキセタン（東亞合成社製ＯＸＴ−２１１）、３−エチル−３−（２−エチルヘキシロキシメチル）オキセタン（東亞合成社製ＯＸＴ−２１２）、１，４−ビス｛［（３−エチル−３−オキセタニル）メトキシ］メチル｝ベンゼン（東亞合成社製ＯＸＴ−１２１）、ビス（３−エチル−３−オキセタニルメチル）エーテル（東亞合成社製ＯＸＴ−２２１）などが挙げられる。さらに、フェノールノボラックタイプのオキセタン化合物なども挙げられる。これらオキセタン化合物は、上記エポキシ化合物と併用してもよく、また、単独で使用してもよい。 Examples of the oxetane compound include the following general formula (I),

As a specific example of an oxetane compound containing an oxetane ring represented by (in the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms), 3-ethyl-3-hydroxymethyloxetane (Toa synthesis) OXT-101), 3-Ethyl-3- (phenoxymethyl) oxetane (OXT-211 manufactured by Toa Synthetic Co., Ltd.), 3-Ethyl-3- (2-ethylhexyloxymethyl) oxetane (OXT-made by Toa Synthetic Co., Ltd.) 212), 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene (OXT-121 manufactured by Toa Synthetic Co., Ltd.), bis (3-ethyl-3-oxetanylmethyl) ether (Toa Synthetic Co., Ltd.) OXT-221) and the like. Further, a phenol novolac type oxetane compound and the like can also be mentioned. These oxetane compounds may be used in combination with the above epoxy compounds, or may be used alone.

The photocurable resin may be any resin that is cured by irradiation with active energy rays and exhibits electrical insulation. In particular, in the present invention, a compound having one or more ethylenically unsaturated groups in the molecule is preferable. Used. As the compound having an ethylenically unsaturated group, a photopolymerizable oligomer, a photopolymerizable vinyl monomer, or the like, which are known and commonly used photocurable monomers, can be used. Further, as the photocurable resin, a polymer such as a carboxyl group-containing resin having an ethylenically unsaturated group as described later can be used.

Examples of the photopolymerizable oligomer include unsaturated polyester-based oligomers and (meth) acrylate-based oligomers. Examples of the (meth) acrylate-based oligomer include epoxy (meth) acrylates such as phenol novolac epoxy (meth) acrylate, cresol novolac epoxy (meth) acrylate, and bisphenol type epoxy (meth) acrylate, urethane (meth) acrylate, and epoxy urethane (meth). ) Acrylic, polyester (meth) acrylate, polyether (meth) acrylate, polybutadiene-modified (meth) acrylate and the like. In addition, in this specification, (meth) acrylate is a generic term for acrylate, methacrylate and a mixture thereof, and the same applies to other similar expressions.

As the photopolymerizable vinyl monomer, known and commonly used ones, for example, styrene derivatives such as styrene, chlorostyrene, α-methylstyrene; vinyl esters such as vinyl acetate, vinyl butyrate or vinyl benzoate; vinyl isobutyl ether, vinyl- Vinyl ethers such as n-butyl ether, vinyl-t-butyl ether, vinyl-n-amyl ether, vinyl isoamyl ether, vinyl-n-octadecyl ether, vinyl cyclohexyl ether, ethylene glycol monobutyl vinyl ether, triethylene glycol monomethyl vinyl ether; acrylamide, (Meta) acrylamides such as methacrylicamide, N-hydroxymethylacrylamide, N-hydroxymethylmethacrylicamide, N-methoxymethylacrylamide, N-ethoxymethylacrylamide, N-butoxymethylacrylamide; triallyl isocyanurate, diallyl phthalate, Allyl compounds such as diallyl isophthalate; 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, tetrahydrofurfreel (meth) acrylate, isobolonyl (meth) acrylate, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, etc. (Meta) acrylic acid esters; hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, pentaerythritol tri (meth) acrylate; methoxyethyl (meth) acrylate, ethoxyethyl Alkoxyalkylene glycol mono (meth) acrylates such as (meth) acrylate; ethylene glycol di (meth) acrylate, butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di ( Alkylene polyol poly (meth) acrylates such as meta) acrylate, trimethylolpropantri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate; diethylene glycol di (meth) acrylate, triethylene glycol di Polyoxyalkylene glycol poly (meth) acrylates, ethoxylated trimethylolpropan triacrylates, propoxylated trimethylol propantri (meth) acrylates, etc. Ta) Acrylate; Poly (meth) acrylates such as neopentyl glycol hydroxypylate di (meth) acrylate; Isocyanurate-type poly (meth) acrylates such as tris [(meth) acryloxyethyl] isocyanurate Can be mentioned. These can be used alone or in combination of two or more, depending on the required characteristics.

(Non-silicon release agent)
The resin layer preferably contains a non-silicone release agent. By containing a non-silicone release agent, when the resin composition is applied onto the film to form a resin layer, uneven coating and repelling are less likely to occur, and the protective film has good peelability from the resin layer. In addition, the laminate property becomes good. Examples of the non-silicon type release agent include an acrylic type release agent and a wax type release agent, and among them, it is preferable to use an acrylic type release agent. The acrylic release agent is preferably a thermoplastic acrylic resin.

In the present invention, an acrylic surface conditioner can be preferably used as the acrylic release agent. Examples of the acrylic surface conditioner include BYK-350, BYK-352, BYK-354, BYK-355, BYK-358N, BYK-361N, BYK-381, BYK-392, BYK-394, BYK-3441, Lintec Corporation T157-2, T197, Kyoeisha Chemical Corporation Polyflow No. 75, No. 77, No. 85HF, No. 90, No. 95, No. 99C and the like can be mentioned.
Among the above non-silicon-based release agents, those that can be used in the composition for solvent-based insulating materials are preferable, and for example, BYK-350, BYK-361N, and BYK-394 are preferable.

The blending amount of the non-silicon release agent is preferably 0.01 to 10% by mass with respect to the total amount of the resin layer.

(Photopolymerization initiator)
When the resin layer contains a photocurable resin as a curable resin, it preferably contains a photopolymerization initiator. As the photopolymerization initiator, any photopolymerization initiator known as a photopolymerization initiator or a photoradical generator can be used.

Examples of the photopolymerization initiator include bis- (2,6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, and bis- (2, 6-Dichlorobenzoyl) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis- (2,6-dimethoxybenzoyl) phenylphosphine oxide, bis- (2,6-dimethoxybenzoyl) 2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,4,6- Bisacylphosphine oxides such as trimethylbenzoyl) -phenylphosphine oxide (IRGACURE819 manufactured by BASF Japan); 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4 6-trimethylbenzoylphenylphosphinic acid methyl ester, 2-methylbenzoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid isopropyl ester, 2,4,6-trimethylbenzoyldiphenylphosphine oxide (IRGACURE TPO manufactured by BASF Japan) Monoacylphosphine oxides such as 1-hydroxy-cyclohexylphenylketone, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propane-1-one, 2- Hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propane-1-one, 2-hydroxy-2-methyl-1-phenylpropane- Hydroxyacetophenones such as 1-one; benzoins such as benzoin, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether; benzoin alkyl ethers; benzophenone, p-methyl Benzoyls such as benzophenone, Michler's ketone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone; acetophenone, 2,2-dimeth Xi-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenylketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino -1-Propanone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2- (dimethylamino) -2-[(4-methylphenyl) methyl) -1-[ 4- (4-morpholinyl) phenyl] -1-butanone, N, N-dimethylaminoacetophenone and other acetophenones; thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethyl Thioxanthones such as thioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylantraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, Anthraquinones such as 2-aminoanthraquinone; Ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzoic acid esters such as ethyl-4-dimethylaminobenzoate, 2- (dimethylamino) ethyl benzoate and p-dimethylbenzoic acid ethyl ester Classes; 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], esterone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole -3-Il]-, Oxime esters such as 1- (O-acetyloxime); bis (η5-2,4-cyclopentadiene-1-yl) -bis (2,6-difluoro-3- (1H-) Pyrrole-1-yl) phenyl) titanium, bis (cyclopentadienyl) -bis [2,6-difluoro-3- (2- (1-pyll-1-yl) ethyl) phenyl] titanium and other titanoses; Examples thereof include phenyldisulfide 2-nitrofluorene, butyloin, anisoine ethyl ether, azobisisobutyronitrile, tetramethylthiuram disulfide and the like. As the photopolymerization initiator, one type may be used alone, or two or more types may be used in combination. Of these, monoacylphosphine oxides and oxime esters are preferable, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide, etanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3. -Il]-, 1- (O-acetyloxime) is more preferable.

The blending amount of the photopolymerization initiator is preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the solid content of the carboxyl group-containing resin. When it is 0.5 parts by mass or more, the surface curability is good, and when it is 20 parts by mass or less, halation is less likely to occur and good resolution can be obtained.

(Photobase generator)
The resin layer can contain a photobase generator. The photobase generator produces one or more basic substances that can function as a catalyst for a thermal curing reaction by changing the molecular structure by irradiation with light such as ultraviolet rays or visible light or by cleaving the molecules. It is a compound. Examples of the basic substance include secondary amines and tertiary amines.

Examples of photobase generators include α-aminoacetophenone compounds, oxime ester compounds, acyloxyimino compounds, N-formylated aromatic amino compounds, N-acylated aromatic amino compounds, nitrobenzyl carbamate compounds, and alcoholic benzyl carbamate. Examples include compounds. Among them, the oxime ester compound and the α-aminoacetophenone compound are preferable, and the oxime ester compound is more preferable. Etanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl]-, 1- (O-acetyloxime) is more preferable. As the α-aminoacetophenone compound, those having two or more nitrogen atoms are particularly preferable. One type of photobase generator may be used alone, or two or more types may be used in combination. In addition, examples of the photobase generator include a quaternary ammonium salt and the like.

As other photobase generators, WPBG-018 (trade name: 9-anthrylmethyl N, N'-diethylcarbamate), WPBG-027 (trade name: (E) -1- [3- (2-hydroxyphenyl) -2-) Propionic] piperidine), WPBG-082 (trade name: guanidinium2- (3-benzoylphenyl) propionate), WPBG-140 (trade name: 1- (anthraquinone-2-yl) ethyl group, etc. can also be used.

Further, some substances of the above-mentioned photopolymerization initiator also function as a photobase generator. As the photopolymerization initiator that also functions as a photobase generator, an oxime ester-based photopolymerization initiator and an α-aminoacetophenone-based photopolymerization initiator are preferable.

The blending amount of the photobase generator is preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the solid content of the carboxyl group-containing resin. When it is 0.5 parts by mass or more, the surface curability is good, and when it is 20 parts by mass or less, halation is less likely to occur and good resolution can be obtained.

(Thermosetting catalyst)
The resin layer can contain a thermosetting catalyst. Examples of such a thermocuring catalyst include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole. , 1- (2-Cyanoethyl) -2-ethyl-4-methylimidazole and other imidazole derivatives; dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N Examples thereof include amine compounds such as -dimethylbenzylamine, 4-methyl-N, N-dimethylbenzylamine, hydrazine compounds such as adipic acid dihydrazide and sebasic acid dihydrazide; and phosphorus compounds such as triphenylphosphine. In addition, 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 adduct and 2,4-diamino-6-methacryloyloxyethyl-S-triazine-isocyanulic acid adduct can also be used, preferably as these adhesion-imparting agents. A compound that also functions is used in combination with a thermosetting catalyst.

The blending amount of the thermosetting catalyst is preferably 0.05 to 20 parts by mass, and more preferably 0.1 to 15 parts by mass with respect to 100 parts by mass of the epoxy resin.

(Colorant)
The resin layer 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 that it does not contain halogen from the viewpoint of reducing the environmental load and affecting the human body.
The amount of the colorant to be blended is not particularly limited.

(Organic solvent)
The resin composition used for forming the resin layer may contain an organic solvent for the purpose of preparing the composition, adjusting the viscosity when applied to the substrate or the support film, and the like. Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethyl benzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol and propylene glycol monomethyl ether. , Dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, diethylene glycol monomethyl ether acetate, tripropylene glycol monomethyl ether and other glycol ethers; ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbi Esters such as tall acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, and solvent naphtha are known. Conventional organic solvents can be used. These organic solvents can be used alone or in combination of two or more.

It is preferable that a small amount of the organic solvent remains in the resin layer after drying. The residual content of the solvent is preferably 0.1 to 4% by mass, more preferably 0.1 to 3% by mass, based on the total amount of the resin layer.

(Other optional ingredients)
Further, the resin layer may contain other curing components and other additives known and commonly used in the field of electronic materials. Examples of other curing components include cyanate ester resin, active ester resin, maleimide compound, and alicyclic olefin polymer. Other additives include thermal polymerization inhibitors, UV absorbers, silane coupling agents, plasticizers, flame retardants, antistatic agents, anti-aging agents, antibacterial / antifungal agents, antifoaming agents, leveling agents, thickening agents. Agent, Adhesion Improving Agent, Tixo Property Improving Agent, Photoinitiating Aid, Sensitizer, Thermoplastic Resin, Organic Filler, Defoaming Agent, Surface Treatment Agent, Dispersant, Dispersion Aid, Surface Modifier, Stabilizer , Fluorescent material and the like.

The resin layer is preferably thermosetting, photocurable or alkali-developed photocurable thermosetting.

When the resin layer is an alkali-developed type, it is preferable to further contain a photopolymerization initiator.

When forming a dry film, first, the resin composition is diluted with the above organic solvent to adjust the viscosity to an appropriate level, and then a comma coater, a blade coater, a lip coater, a rod coater, a squeeze coater, a reverse coater, and a transfer coater are formed. Apply to a uniform thickness on the support film with a roll coater, gravure coater, spray coater, or the like. Then, the applied composition is usually dried at a temperature of 40 to 130 ° C. for 1 to 30 minutes to form a resin layer. The coating film thickness is not particularly limited, but is generally selected as appropriate in the range of 5 to 150 μm, preferably 10 to 60 μm after drying. After forming the resin layer made of the resin composition on the first film (in many cases, the support film), the surface of the resin layer is further subjected to the purpose of preventing dust from adhering to the surface of the resin layer. , Laminate a peelable protective film. The second film (in many cases, a protective film) may be one that is smaller than the adhesive force between the resin layer and the first film when the second film is peeled off.

In the present invention, the resin composition may be applied on the protective film and dried to form a resin layer, and the support film may be laminated on the surface thereof. That is, as the film to which the resin composition is applied when producing the dry film in the present invention, either a support film or a protective film may be used.

In the dry film of the present invention, a support film or a protective film, that is, a second film is peeled off from the resin layer and bonded onto the base material by a laminator or the like so that the resin layer comes into contact with the base material. A resin layer can be formed on the resin layer.

The base material includes a printed wiring board and a flexible printed wiring board whose circuit is formed of copper or the like in advance, as well as paper phenol, paper epoxy, glass cloth epoxy, glass polyimide, glass cloth / non-woven cloth epoxy, and glass cloth / paper epoxy. , Synthetic fiber epoxy, fluororesin / polyethylene / polyimideene ether, polyphenylene oxide / cyanate, etc. are used for high frequency circuit copper-clad laminates, etc., and all grades (FR-4, etc.) of copper-clad laminates are used. Plates, other metal substrates, polyimide films, PET films, polyethylene naphthalate (PEN) films, glass substrates, ceramic substrates, wafer plates and the like can be mentioned.

The resin layer of the dry film of the present invention is excellent in various properties such as heat resistance, chemical resistance, hygroscopicity, adhesion, and electrical properties by heating to a temperature of 100 to 220 ° C. and thermosetting, for example. A cured film (cured product) can be formed.

When the resin layer of the dry film of the present invention is photohard, the exposed portion (light-irradiated portion) is cured by exposing the resin layer to light (light irradiation). When the resin layer of the dry film is photocurable and thermosetting and contains a photobase generator, the exposed part is heated after activating the base of the exposed part (the part irradiated with light). Hardens to the deep part. Specifically, a contact type or a non-contact type is used to selectively expose with active energy rays through a photomask in which a pattern is formed, or to directly expose a pattern with a laser direct exposure machine. A patterned cured film can be formed by developing the unexposed portion with a dilute alkaline aqueous solution (for example, a 0.3 to 3 mass% sodium carbonate aqueous solution).

The exposure machine used for the above-mentioned active energy ray irradiation may be a device equipped with a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a mercury short arclamp, etc., and irradiates ultraviolet rays in the range of 350 to 450 nm. Further, a direct drawing device (for example, a laser direct imaging device that directly draws an image with a laser based on CAD data from a computer) can also be used. The lamp light source or the laser light source of the direct drawing machine may have a maximum wavelength in the range of 350 to 410 nm. The amount of exposure for image formation varies depending on the film thickness and the like, but is generally 10 to 1000 mJ / cm ² , preferably 20 to 800 mJ / cm ² .

The developing method can be a dipping method, a shower method, a spray method, a brush method, etc., and the developing solution includes potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, etc. Alkaline aqueous solutions such as ammonia and amines can be used.

The dry film of the present invention is suitably used for forming a cured film on a printed wiring board such as a package substrate, more preferably used for forming a permanent film, and more preferably a solder resist. , An interlayer insulating layer, used to form a coverlay, and particularly preferably to form a solder resist.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. In the following, "part" and "%" are all based on mass unless otherwise specified.

(Synthesis of Carboxylic Acid Group-Containing Resin A-1 with Ethylene Unsaturated Group)
Diethylene glycol monoethyl ether acetate 600 g and orthocresol novolac type epoxy resin (manufactured by DIC, EPICLON N-695, softening point 95 ° C., epoxy equivalent 214, average number of functional groups 7.6) 1070 g (number of glycidyl groups (total number of aromatic rings): 5 .0 mol), 360 g (5.0 mol) of acrylic acid, and 1.5 g of hydroquinone were charged and heated and stirred at 100 ° C. to uniformly dissolve.
Then, 4.3 g of triphenylphosphine was charged, heated to 110 ° C. for 2 hours, then heated to 120 ° C. and further reacted for 12 hours. To the obtained reaction solution, 415 g of aromatic hydrocarbon (Solbesso 150) and 456.0 g (3.0 mol) of tetrahydrophthalic anhydride were charged, reacted at 110 ° C. for 4 hours, cooled, and ethylenically unsaturated. A solution of a carboxyl group-containing resin A-1 having a group was obtained.
The solid content of the carboxyl group-containing resin A-1 solution thus obtained was 65%, and the acid value of the solid content was 89 mgKOH / g.

(Synthesis of Carboxylic Acid Group-Containing Resin A-2)
431 g of dipropylene glycol monomethyl ether was placed in a 2000 ml flask equipped with a stirrer and a cooling tube, and heated to 90 ° C. under a nitrogen stream. A mixture of 104.2 g of styrene, 296.6 g of methacrylic acid, and 23.9 g of dimethyl 2,2'-azobis (2-methylpropionate) (manufactured by Wako Pure Chemical Industries, Ltd .: V-601) was mixed and dissolved for 4 hours. It was added dropwise to the flask.
In this way, an alkali-soluble resin solution A-2 as a carboxyl group-containing resin was obtained. This resin solution had a solid content acid value of 140 mgKOH / g and a solid content of 50% by mass.

(Adjustment of surface-treated inorganic filler (silica))
70 g of spherical silica (SFP-30M manufactured by Electrochemical Industry Co., Ltd.), 28 g of PMA (propylene glycol monomethyl ether acetate) as a solvent, and KBM-503 (3-methacryloxypropyltri) manufactured by Shin-Etsu Chemical Co., Ltd. as a silane coupling agent. 2 g of methoxysilane) was uniformly dispersed to obtain a silica solvent-dispersed product B-1.

(Arithmetic mean surface roughness Ra measurement of protective film (second film))
The surface roughness Ra of the protective film was measured using a laser microscope VK-8500 (manufactured by Keyence Co., Ltd., measurement magnification × 2000 times, Z-axis measurement pitch 10 nm). For the transparent film that transmits laser light, the surface roughness Ra was measured after the Au sputtering treatment.

[Examples 1 to 10, Comparative Examples 1 to 8]
The components in the formulation shown in the following Table 1-3 were blended at proportions shown in Tables 1 to 3 (parts by weight), were preliminarily mixed using a stirrer and kneaded with bi Zumiru, prepare a curable resin composition did.

(Making a dry film)
The curable resin composition obtained as described above is applied onto a polyethylene terephthalate film (Toray Industries, Inc. Lumirror T60) having a support film thickness of 38 μm, dried at a temperature of 80 ° C. for 15 minutes, and has a thickness of 20 μm. A photocurable resin layer was formed. Next, a protective film was laminated on the resin layer to prepare a dry film.

(Melted viscosity of resin layer)
The dry film prepared above using CVP-300 manufactured by Nikko Material Co., Ltd. was laminated at a laminating temperature of 80 ° C. to prepare a resin layer (laminated body of resin layers) having a thickness of about 300 μm and a width of 20 mm, and Thermo Scientific Co., Ltd. The melt viscosity was measured under the following measurement conditions using RS-6000 manufactured by Japan.
(Measurement conditions for melt viscosity)
Heating rate: 5 ° C / min
Measurement frequency: 1Hz
Measurement pressure: 3Pa

(Adhesion)
In the preparation of the dry film, the degree of sticking of the protective film when the protective film was stuck with a roll laminator at 50 ° C. was evaluated.
◯: No peeling of the protective film.
X: The protective film floats or peels off.

(Reworkability)
The protective film of the dry film produced above was peeled off, the resin layer was placed on a copper-clad laminate at room temperature, and it was evaluated whether rework could be performed after 1 minute.
◯: Rework is possible without sticking to the copper-clad laminate.
X: The film sticks to the copper-clad laminate, and the film is removed during rework.

(Smoothness)
The protective film of the dry film produced above was peeled off, and the resin layer was laminated on a copper-clad laminated half plate having a circuit formed in a comb shape of L / S = 12/12 using CVP-300 manufactured by Nikko Material Co., Ltd. The smoothness of the surface of the resin layer after lamination was evaluated.
◯: Smoothness is obtained.
X: Not smooth and uneven.

＊１：上記で合成したカルボキシル基含有光硬化性樹脂Ａ−１
＊２：上記で合成したカルボキシル基含有樹脂Ａ−２
＊３：ＢＡＳＦジャパン社製イルガキュアＴＰＯ（２，４，６−トリメチルベンゾイル−ジフェニル−フォスフィンオキサイド）
＊４：日本化薬社製カヤキュアＤＥＴＸ−Ｓ（２，４−ジエチルチオキサントン）
＊５：日本化薬社製ＤＰＨＡ（ジペンタエリスリトールヘキサアクリレート）
＊６：上記で調整した表面処理されたシリカフィラー（アドマテックス社製アドマファインＳＯ−Ｃ２（球状シリカ））溶剤分散品（表中の量は固形分量）
＊７：アドマテックス社製アドマファインＳＯ−Ｃ２（球状シリカ）
＊８：堺化学工業社製Ｂ−３０（シリカアルミナで表面処理された硫酸バリウム）
＊９：ＤＩＣ社製エピクロンＮ−７４０（フェノールノボラック型エポキシ樹脂）
＊１０：三菱化学社製ＹＸ−４０００（ビフェニル型エポキシ樹脂）
＊１１：ビックケミージャパン社製ＢＹＫ−３６１Ｎ（非シリコン系剥離剤（ポリアクリレート系表面調整剤））
＊１２：プロピレングリコールモノメチルエーテルアセテート
＊１３：東洋紡社製Ｐ−１０１６（無延伸ポリプロピレンフィルム）
＊１４：王子エフテックス社製アルファンＥＲ−４４０（二軸延伸ポリプロピレンフィルム）
＊１５：王子エフテックス社製アルファンＭＡ−４１１（二軸延伸ポリプロピレンフィルム）
＊１６：王子エフテックス社製アルファンＭＡ−４２０（二軸延伸ポリプロピレンフィルム）
＊１７：王子エフテックス社製アルファンＥ−２０１Ｆ（二軸延伸ポリプロピレンフィルム）
＊１８：フタムラ化学社製ＦＯＲ−ＭＰ（二軸延伸ポリプロピレンフィルム）

* 1: Carboxylic acid group-containing photocurable resin A-1 synthesized above
* 2: Carboxylic acid group-containing resin A-2 synthesized above
* 3: BASF Japan's Irgacure TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide)
* 4: Kayacure DETX-S (2,4-diethylthioxanthone) manufactured by Nippon Kayaku Co., Ltd.
* 5: DPHA (dipentaerythritol hexaacrylate) manufactured by Nippon Kayaku Co., Ltd.
* 6: Surface-treated silica filler (Admafine SO-C2 (spherical silica) manufactured by Admatex) solvent-dispersed product prepared above (the amount in the table is the amount of solid content)
* 7: Admafine SO-C2 (spherical silica) manufactured by Admatex
* 8: Sakai Chemical Industry Co., Ltd. B-30 (barium sulfate surface-treated with silica-alumina)
* 9: Epicron N-740 manufactured by DIC (phenol novolac type epoxy resin)
* 10: YX-4000 manufactured by Mitsubishi Chemical Corporation (biphenyl type epoxy resin)
* 11: BYK-361N manufactured by Big Chemie Japan (non-silicon release agent (polyacrylate surface conditioner))
* 12: Propylene glycol monomethyl ether acetate * 13: P-1016 (non-stretched polypropylene film) manufactured by Toyobo Co., Ltd.
* 14: Alfan ER-440 (biaxially stretched polypropylene film) manufactured by Oji F-Tex Co., Ltd.
* 15: Alfan MA-411 (biaxially stretched polypropylene film) manufactured by Oji F-Tex Co., Ltd.
* 16: Alfan MA-420 (biaxially stretched polypropylene film) manufactured by Oji F-Tex Co., Ltd.
* 17: Alfan E-201F (biaxially stretched polypropylene film) manufactured by Oji F-Tex Co., Ltd.
* 18: FOR-MP (biaxially stretched polypropylene film) manufactured by Futamura Chemical Co., Ltd.

From the results shown in the above table, it can be seen that the dry film of the present invention has a resin layer having excellent reworkability and smoothness without floating or peeling of the protective film.

1 Dry film 11 First film 12 Second film 13 Resin layer

Claims (6)

A carboxyl group-containing resin, an epoxy resin , a surface-treated inorganic filler and a thermoplastic acrylic resin sandwiched between the first film, the second film, and the first film and the second film. A dry film having a resin layer made of a curable resin composition containing a non-silicone release agent .
The melt viscosity of the resin layer at 50 ° C. is 1.0 × 10 ^{4 to} 1.0 × 10 ⁶ dPa · s.
The arithmetic mean surface roughness Ra of the surface of the second film in contact with the resin layer is 0.1 μm or more.
A dry film characterized in that the surface of the resin layer in contact with the second film is a surface laminated on a base material. The dry film according to claim 1, wherein the minimum value of the melt viscosity of the resin layer at 90 to 120 ° C. is 50 to 900 dPa · s. The dry film according to claim 1 or 2, wherein the resin layer does not contain an inorganic filler having a decomposition temperature of less than 250 ° C. The dry film according to any one of claims 1 to 3 , wherein the dry film is for forming a solder resist. A cured product obtained by curing the resin layer of the dry film according to any one of claims 1 to 4 . A printed wiring board comprising the cured product according to claim 5 .

Images