KR102543357B1 - Laminated film - Google Patents

Abstract

The present invention provides a laminated film in which wrinkles are less likely to occur in the resin layer and the film is less likely to remain on the resin layer. (A) a resin layer and (B) a film having a 5% elongation load per unit width at 80 ° C. of more than 90 g / mm and 500 g / mm or less, and the melt viscosity of the resin layer (A) at 80 ° C. is 10 to 10000 dPa. and the laminated film characterized by s.

Description

Laminated film {LAMINATED FILM}

The present invention relates to laminated films.

Conventionally, a laminated film (dry film) is used as one of the means for forming a protective film or an insulating layer such as a solder resist or an interlayer insulating layer installed on a printed wiring board used in electronic devices, etc. (for example, Patent Documents 1 and 2 ), with the recent thinning of substrates and miniaturization of circuits, the demand for laminated films for forming protective films such as solder resists and insulating layers is increasing. A laminated film has a resin layer obtained through a drying process after applying a resin composition having desired characteristics onto a support film, and is generally marketed in a state in which a protective film for protecting the surface opposite to the support film is further laminated. are being distributed to After attaching the resin layer of the laminated film to the substrate (hereinafter also referred to as "lamination"), patterning or hardening treatment is performed to form the above protective film or insulating layer on the printed wiring board.

When attaching a laminated film for forming a film on a wiring board on which a fine patterned circuit is formed, such as a laminated film for forming a solder resist, since followability to the circuit is required, vacuum lamination or SUS under heating conditions It is common to perform hot pressing with a plate or the like to obtain a more flattened film.

Japanese Unexamined Patent Publication (Hei) 7-15119 Japanese Unexamined Patent Publication No. 2002-162736

It is seen that wrinkles are generated in the resin layer of the laminated film after a series of bonding processes of the laminated film. It has been found that the existence of such wrinkles causes not only poor appearance but also a problem in that desired characteristics such as solder heat resistance are lowered because the groove portion of the wrinkles is thinner than the designed film thickness.

In addition, when the support film (or protective film) of the laminated film is peeled from the resin layer using a mechanical means, for example, an auto peeler, after a series of laminated film bonding steps, the film is fragmented and remains on the resin layer. It is known that there are cases. If the film remains on the resin layer, it is also known that there is a problem that residual development occurs during the development process.

Accordingly, an object of the present invention is to provide a laminated film in which wrinkles are less likely to occur in the resin layer and the film is less likely to remain on the resin layer.

As a result of intensive examination in view of the above, the present inventors have used a film having a 5% elongation load per unit width at 80°C of more than 90 g/mm and not more than 500 g/mm, and as a resin layer, a melt viscosity at 80°C of 10 to 10000 dPa·s, it was discovered that the above problems could be solved, and the present invention was completed.

That is, the laminated film of the present invention has (A) a resin layer and (B) a film having a 5% elongation load per unit width at 80°C of more than 90 g/mm and 500 g/mm or less, and is characterized in (A) above.

As for the laminated|multilayer film of this invention, it is preferable that the said (A) resin layer is photosensitive.

As for the laminated|multilayer film of this invention, it is preferable that the said (A) resin layer contains alkali-soluble resin, a photoinitiator, and a thermosetting resin.

It is preferable to use the laminated|multilayer film of this invention by adhering to the surface of a wiring board.

It is preferable to adhere the laminated|multilayer film of this invention to the surface of a wiring board using a vacuum laminator.

The laminated film of the present invention is preferably adhered to the wiring board surface by lamination treatment using a vacuum laminator and subsequent flattening treatment by hot pressing.

It is preferable to use the laminated|multilayer film of this invention for formation of the permanent film of a wiring board.

According to the present invention, it is possible to provide a laminated film in which wrinkles are less likely to occur in the resin layer and the film is less likely to remain on the resin layer.

1 is a schematic cross-sectional view schematically showing one embodiment of a laminated structure of the present invention.
Fig. 2 is a schematic cross-sectional view schematically showing another embodiment of the laminated structure of the present invention.

<Laminated film>

The laminated film of the present invention has (A) a resin layer and (B) a film having a 5% elongation load per unit width at 80 ° C. of more than 90 g / mm and less than or equal to 500 g / mm (hereinafter also referred to as “(B) film”), It is characterized in that the melt viscosity at 80 ° C. of the resin layer (A) is 10 to 10000 dPa·s. It is considered that the main cause of the occurrence of wrinkles in the resin layer as described above is wrinkles generated in the unpeeled film during vacuum lamination under heating conditions or subsequent hot pressing. That is, after laminating the laminated film so that the resin layer is in contact with the wiring board, vacuum lamination under heating conditions is usually performed before peeling the support film from the resin layer, but if wrinkles occur in the support film in this step, this may be It is thought that wrinkles are also generated in the resin layer by being transferred to the paper layer. In the case of using a film having a 5% elongation load per unit width at 80°C of more than 90 g/mm and less than or equal to 500 g/mm, wrinkles are unlikely to occur in the film even under the temperature conditions of thermal lamination, and as a result, it is considered that wrinkles are less likely to occur in the resin layer as well. It becomes.

In addition, the value of the 5% extension load per unit width at (B) 80 degreeC is the maximum value.

The laminated film of the present invention has a structure in which (A) a resin layer and (B) a film are laminated (FIG. 1). Another resin layer may be formed between the film (B) and the resin layer (A) within a range not impairing the effects of the present invention. The laminated film of the present invention is laminated with respect to the wiring board so that (A) the resin layer is located on the wiring board side, and (B) the film is located on the surface layer side, that is, on the opposite side to the wiring board as viewed from the (A) resin layer. can be used by doing Thereby, even if vacuum lamination is performed under heating conditions, wrinkles are less likely to occur in the (A) resin layer.

In the laminated film of the present invention, in order to protect the surface of the (A) resin layer, it is preferable to further laminate the (C) film on the opposite side of the (B) film (FIG. 2). What is necessary is just to peel the (C) film laminated|stacked in this way, when laminating the (A) resin layer to a wiring board. If necessary, another resin layer may be formed between the (A) resin layer and the (C) film.

In the laminated film of the present invention, by setting the 5% elongation load of the (B) film to more than 90 g/mm, not only wrinkles are less likely to occur during vacuum lamination under heating conditions as described above, but also mechanical means such as auto peeler. (B) Even if the film is peeled off, film residue is unlikely to occur. Moreover, even if it has the (C) film on the opposite side to the (B) film like the laminated|multilayer film shown in FIG. 2 by making said 5% extension load of the (B) film exceed 90 g/mm, roll laminated film Wrinkles that occur due to the balance between the tension of the (B) film and the (C) film when wound up are less likely to occur.

Moreover, even if the laminated film of this invention has the (C) film on the opposite side to the (B) film like the laminated|multilayer film shown in FIG. 2 by setting the said extension load to 500 g/mm or less, roll laminated|multilayer film When winding, due to the balance between the tension of the (B) film and the (C) film, wrinkles on the surface of the (A) resin layer on the (C) film side are less likely to occur, and the circuit followability of the (A) resin layer is good This makes it easier for the resin to entrain between the narrow pitches.

It is preferable that it is more than 90 g/mm and 400 g/mm or less, and, as for the said extension load, it is more preferable that it is more than 90 g/mm and 300 g/mm or less.

In the laminated film of the present invention, the resin layer (A) has a melt viscosity of 10 to 10000 dPa·s at 80°C. When the melt viscosity is 10 dPa·s or more, the fluidity of the resin layer during thermal lamination does not become excessively high during vacuum lamination under heating conditions, so wrinkles are less likely to occur. When the melt viscosity is 10000 dPa·s or less, the fluidity of the resin layer at the time of vacuum lamination under heating conditions is good and the circuit followability becomes better, so that the resin easily entrains even between narrow pitches. The melt viscosity is preferably 50 to 5000 dPa·s, more preferably 100 to 4000 dPa·s, and still more preferably 200 to 2500 dPa·s.

Hereinafter, each constituent requirement is described in detail.

[(A) Resin Layer]

The resin layer of the laminated film of the present invention is obtained through a drying step after applying the resin composition to the supporting film. The resin composition is not particularly limited, and a conventionally known resin composition used for forming a protective layer or insulating layer provided on a printed wiring board such as a solder resist, an interlayer insulating layer, and a coverlay may be used. Although the film thickness of a resin layer is not specifically limited, It is preferable that the film thickness after drying is 1-200 micrometers. In the case of a photosensitive curable resin layer, in the case of 200 μm or less, a decrease in deep curability can be suppressed. A resin layer contains curable resin and a filler, and it is preferable that the compounding quantity of a filler is 10 mass % or more based on the total amount of the resin layer of the dry film excluding the solvent. As specific examples of the resin composition below, a photocurable resin composition containing a photopolymerization initiator, a photocurable thermosetting resin composition, a photocurable resin composition containing a photobase generator, a photocurable resin composition containing a photoacid generator, negative photosensitive resin compositions such as type photocurable resin composition, positive type photocurable resin composition, alkali development type photocurable resin composition, solvent development type photocurable resin composition, thermosetting resin composition, swelling exfoliation type resin composition, dissolution exfoliation type resin composition Although exemplified, it is not limited to these. Among them, a photosensitive resin composition is preferable, and a photosensitive resin composition containing an alkali-soluble resin, a photopolymerization initiator, a compound having an ethylenically unsaturated bond, and a thermosetting resin is more preferable.

(Photocurable Thermosetting Resin Composition)

As an example of the photocurable thermosetting resin composition, a resin composition containing an alkali-soluble resin, a photopolymerization initiator, a compound having an ethylenically unsaturated bond, and a thermosetting resin will be described below.

The alkali-soluble resin is a resin that contains at least one functional group from among a phenolic hydroxyl group, a thiol group, and a carboxyl group, and is soluble in an alkali solution, preferably a compound having two or more phenolic hydroxyl groups, a carboxyl group-containing resin, and a phenolic hydroxyl group. and a compound having a carboxyl group and a compound having two or more thiol groups. As the alkali-soluble resin, a carboxyl group-containing resin or a phenolic hydroxyl group-containing resin can be used, but a carboxyl group-containing resin is preferable.

Carboxyl group-containing resin is a component that is cured by polymerization or crosslinking by light irradiation, and can be made alkali developable by containing a carboxyl group. Further, from the viewpoint of photocurability and development resistance, it is preferable to have an ethylenically unsaturated bond in the molecule other than a carboxyl group, but only a carboxyl group-containing resin having no ethylenically unsaturated double bond may be used. As the ethylenically unsaturated bond, those derived from acrylic acid or methacrylic acid or derivatives thereof are preferable. Among the carboxyl group-containing resins, carboxyl group-containing resins having a copolymerization structure, carboxyl group-containing resins having a urethane structure, carboxyl group-containing resins using an epoxy resin as a starting material, and carboxyl group-containing resins using a phenolic compound as a starting material are preferred. Specific examples of the carboxyl group-containing resin include the compounds listed below (which may be oligomers or polymers).

(1) A dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, or hexahydrophthalic anhydride is added to a hydroxyl group present in a side chain by reacting (meth)acrylic acid with a bifunctional or more multifunctional epoxy resin to contain a carboxyl group. photosensitive resin. Here, it is preferable that the bifunctional or more polyfunctional epoxy resin is solid.

(2) Carboxyl group-containing photosensitive resin obtained by reacting (meth)acrylic acid with a multifunctional epoxy resin obtained by further epoxidizing the hydroxyl group of the bifunctional epoxy resin with epichlorohydrin and adding a dibasic acid anhydride to the generated hydroxyl group. Here, it is preferable that the bifunctional epoxy resin is solid.

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

(4) Bisphenol A, bisphenol F, bisphenol S, novolak-type phenolic resin, poly-p-hydroxystyrene, condensates of naphthol and aldehydes, condensates of dihydroxynaphthalene and aldehydes, etc. in one molecule, 2 A reaction product obtained by reacting a monocarboxylic acid containing an unsaturated group such as (meth)acrylic acid with a reaction product obtained by reacting a compound having two or more phenolic hydroxyl groups with an alkylene oxide such as ethylene oxide and propylene oxide. A carboxyl group-containing photosensitive resin obtained by reacting a polybasic acid anhydride with.

(5) A monocarboxylic acid containing an unsaturated group is reacted with 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, , Carboxyl group-containing photosensitive resin obtained by making a polybasic acid anhydride react with the obtained reaction product.

(6) Diisocyanate 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, and acrylic polyols , bisphenol A-based alkylene oxide adduct diol, a diol compound having a phenolic hydroxyl group and an alcoholic hydroxyl group, etc., a polyaddition reaction of a urethane resin terminal formed by reacting an acid anhydride with a terminal carboxyl group-containing urethane profit.

(7) Molecules such as hydroxyalkyl (meth)acrylate during the synthesis of a carboxyl group-containing urethane resin by polyaddition reaction of diisocyanate, a carboxyl group-containing dialcohol compound such as dimethylolpropionic acid and dimethylolbutyric acid, and a diol compound A carboxyl group-containing urethane resin obtained by adding a compound having one hydroxyl group and one or more (meth)acryloyl groups in the terminal to form (meth)acrylation.

(8) During synthesis of diisocyanate, carboxyl group-containing dialcohol compound and carboxyl group-containing urethane resin by polyaddition reaction of diol compound, isophorone diisocyanate and pentaerythritol triacrylate equimolar reaction product, etc. A carboxyl group-containing urethane resin obtained by adding a compound having an isocyanate group and at least one (meth)acryloyl group and carrying out terminal (meth)acrylation.

(9) A carboxyl group-containing photosensitive resin obtained by copolymerization of 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.

(10) A carboxyl group-containing poly obtained by reacting a dicarboxylic acid such as adipic acid, phthalic acid, or hexahydrophthalic acid with a polyfunctional oxetane resin described later to add a dibasic acid anhydride to a primary hydroxyl group generated. Formed by further 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, to an ester resin A photosensitive resin containing a carboxyl group.

(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, (meth)acrylate here is a general term for acrylates, methacrylates, and mixtures thereof, and the same applies to other similar expressions below.

It is preferable that the acid value of carboxyl group-containing resin is 40-150 mgKOH/g. Alkali image development becomes favorable because the acid value of carboxyl group-containing resin shall be 40 mgKOH/g or more. Further, 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 50-130 mgKOH/g.

The blending amount of the alkali-soluble resin is, for example, 15 to 60% by mass, preferably 20 to 60% by mass, based on the total amount of the resin layer excluding the solvent. 15% by mass or more, preferably 20% by mass or more, the coating film strength can be improved. Moreover, by setting it as 60 mass % or less, viscosity becomes suitable and workability improves. More preferably, it is 30-50 mass %.

As the photopolymerization initiator used for photopolymerizing the alkali-soluble resin described above, a known photopolymerization initiator can be used. Among them, an oxime ester photopolymerization initiator having an oxime ester group, an α-aminoacetophenone photopolymerization initiator, and an acylphosphine oxide photopolymerization initiator. , titanocene-based photopolymerization initiators are preferred. A photoinitiator may be used individually by 1 type, and may be used in combination of 2 or more types.

It is preferable that the compounding quantity of a photoinitiator is 0.01-20 mass parts with respect to 100 mass parts of alkali-soluble resin. This is because, within this range, the photocurability on copper is sufficient, the curability of the coating film is improved, the coating film properties such as chemical resistance are improved, and the deep part curability is also improved. More preferably, it is 0.5-15 mass parts with respect to 100 mass parts of alkali-soluble resin.

It is preferable to make the compounding quantity in the case of using an oxime ester system photoinitiator into 0.01-5 mass parts with respect to 100 mass parts of alkali-soluble 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. In addition, by setting it as 5 parts by mass or less, light absorption on the surface of the coating film is suppressed, and the curability of the deep portion tends to be improved. More preferably, it is 0.1-3 mass parts with respect to 100 mass parts of alkali-soluble resin.

When using an α-aminoacetophenone-based photopolymerization initiator or an acylphosphine oxide-based photopolymerization initiator, each compounding amount is preferably 0.01 to 15 parts by mass with respect to 100 parts by mass of the alkali-soluble 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, by setting it as 15 mass parts or less, the effect of reducing sufficient outgas is acquired, and also light absorption on the surface of a hardened film is suppressed, and the sclerosis|hardenability of a deep part also improves. More preferably, it is 0.5-10 mass parts with respect to 100 mass parts of alkali-soluble resin.

In combination with the above photopolymerization initiator, a photoinitiation aid or sensitizer may be used. Examples of photoinitiation aids or sensitizers include benzoin compounds, acetophenone compounds, anthraquinone compounds, thioxanthone compounds, ketal compounds, benzophenone compounds, tertiary amine compounds, and xanthone compounds. Although these compounds can be used as a photopolymerization initiator in some cases, it is preferable to use them in combination with a photopolymerization initiator. In addition, a photoinitiation adjuvant or a sensitizer may be used individually by 1 type, and may use 2 or more types together.

The photocurable thermosetting resin composition contains a thermosetting resin for the purpose of improving properties such as heat resistance and insulation reliability. Examples of the thermosetting resin include isocyanate compounds, block isocyanate compounds, amino resins, maleimide compounds, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, polyfunctional epoxy compounds, polyfunctional oxetane compounds, episulfide resins, and the like. A well-known and commonly used thermosetting resin can be used. Among these, a preferable thermosetting resin is a thermosetting resin having at least either one of a plurality of cyclic ether groups and cyclic thioether groups (hereinafter abbreviated as cyclic (thio) ether groups) in one molecule. There are many commercially available thermosetting resins having these cyclic (thio)ether groups, and various properties can be imparted depending on their structures. As these thermosetting resins, those having a softening point or a melting point of 100°C or less are preferably included. When an epoxy resin having a softening point or a melting point of 100° C. or less is used, the time required for the viscosity of the resin layer to decrease due to heating during lamination is shortened, the circuit followability of the resin layer is improved, and the resin layer is easily flattened, resulting in heat resistance. This is desirable because it improves These thermosetting resins may be used alone or in combination with thermosetting resins having a softening point or melting point exceeding 100°C.

The compounding amount of the thermosetting resin having a plurality of cyclic (thio) ether groups in the molecule is preferably 0.3 to 2.5 equivalents, more preferably 0.5 to 2.0 equivalents with respect to 1 equivalent of the alkali-soluble groups of the alkali-soluble resin. By setting the compounding amount of the thermosetting resin having a plurality of cyclic (thio)ether groups in the molecule to 0.3 equivalent or more, no alkali-soluble group remains in the cured film, and heat resistance, alkali resistance, electrical insulation, etc. are improved. Moreover, by setting it as 2.5 equivalent or less, a low molecular weight cyclic (thio) ether group does not remain|survive in a dry coating film, but the intensity|strength of a cured film etc. improves.

When using a thermosetting resin having a plurality of cyclic (thio)ether groups in the molecule, it is preferable to contain a thermosetting catalyst. Examples of such a thermal curing catalyst include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, and 4-phenylimidazole. , imidazole derivatives such as 1-cyanoethyl-2-phenylimidazole and 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; Amines such as dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N,N-dimethylbenzylamine Hydrazine compounds, such as adipic acid dihydrazide and sebacic acid dihydrazide; Phosphorus compounds, such as a triphenylphosphine, etc. are mentioned. In addition, guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine Azine, 2-vinyl-4,6-diamino-S-triazine/isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine/isocyanuric acid S-triazine derivatives such as adducts can also be used, and compounds that also function as these adhesion imparting agents are preferably used in combination with a heat curing catalyst.

The blending amount of the thermosetting catalyst is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass, based on 100 parts by mass of the thermosetting resin having a plurality of cyclic (thio)ether groups in the molecule.

The photocurable thermosetting resin composition may contain a compound having at least one ethylenically unsaturated bond in the molecule as a photosensitive monomer in addition to the alkali-soluble resin, photopolymerization initiator and thermosetting resin described above. A photosensitive monomer helps photocuring of alkali-soluble resin by active energy ray irradiation.

Examples of the compound used as the compound having an ethylenically unsaturated bond include commonly known polyester (meth)acrylates, polyether (meth)acrylates, urethane (meth)acrylates, and carbonate (meth)acrylates. , epoxy (meth)acrylate, etc. are mentioned. Specifically, hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate; Diacrylates of glycols, such as ethylene glycol, methoxy tetraethylene glycol, polyethylene glycol, and propylene glycol; acrylamides such as N,N-dimethylacrylamide, N-methylolacrylamide, and N,N-dimethylaminopropylacrylamide; aminoalkyl acrylates such as N,N-dimethylaminoethyl acrylate and N,N-dimethylaminopropyl acrylate; Polyhydric alcohols such as hexanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, and tris-hydroxyethyl isocyanurate, or ethylene oxide adducts, propylene oxide adducts, or ε-caprolactone additions thereof polyhydric acrylates such as water; polyhydric acrylates such as phenoxy acrylate, bisphenol A diacrylate, and ethylene oxide adducts or propylene oxide adducts of these phenols; polyhydric acrylates of glycidyl ethers such as glycerin diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, and triglycidyl isocyanurate; Not limited to the above, acrylates and melamine acrylates obtained by directly acrylated polyols such as polyether polyol, polycarbonate diol, hydroxyl group-terminated polybutadiene, and polyester polyol, or urethane acrylate through diisocyanate , And it can be used by appropriately selecting from at least any one of each methacrylate corresponding to the above acrylate.

An epoxy acrylate resin in which acrylic acid is reacted with a polyfunctional epoxy resin such as cresol novolac type epoxy resin, or a hydroxy acrylate such as pentaerythritol triacrylate and isophorone are further added to the hydroxy group of the epoxy acrylate resin An epoxy urethane acrylate compound obtained by reacting a half urethane compound of diisocyanate such as diisocyanate can also be used as the photosensitive monomer. Such an epoxy acrylate-type resin can improve photocurability without reducing set-to-touch property.

The compounding amount of the compound having an ethylenically unsaturated bond 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 alkali-soluble resin. The photocurability of a photocurable thermosetting resin composition improves by making the compounding quantity of the compound which has an ethylenically unsaturated bond into 5 mass parts or more. Moreover, coating film hardness can be improved by making a compounding quantity into 100 mass parts or less.

The photocurable thermosetting resin composition may contain other components such as fillers, colorants, elastomers, and thermoplastic resins in addition to the above components. Hereinafter, these components are also explained.

It is preferable to mix|blend a filler with the photocurable thermosetting resin composition for the purpose of raising physical strength etc. of the hardened|cured material obtained and adjusting a viscosity. As the filler, a known and commonly used inorganic or organic filler can be used, but barium sulfate, spherical silica, titanium oxide, Neuburg silica particles and talc are particularly preferably used. Further, for the purpose of imparting flame retardancy, aluminum hydroxide, magnesium hydroxide, boehmite, and the like can also be used. These may be used alone or in combination of two or more.

The average particle diameter (D50) of the inorganic filler is preferably 25 µm or less, more preferably 10 µm or less, still more preferably 3 µm or less. Here, D50 is the particle diameter at 50% of volume accumulation obtained using the laser diffraction scattering particle size distribution measurement method based on the Mie scattering theory. More specifically, it can be measured by creating a particle size distribution of fine particles on a volume basis with a laser diffraction scattering type particle size distribution analyzer and taking the median diameter as the average particle diameter. As the measurement sample, a sample obtained by dispersing fine particles in water by ultrasonic waves can be preferably used. As the laser diffraction type particle size distribution analyzer, LA-500 manufactured by Horiba Seisakusho Co., Ltd. or the like can be used.

Examples of the shape of the filler include spherical shape, acicular shape, plate shape, scale shape, hollow shape, irregular shape, hexagonal shape, cubic shape, and flaky shape.

The addition amount of the filler is preferably 500 parts by mass or less, more preferably 0.1 to 350 parts by mass, based on 100 parts by mass of the alkali-soluble 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.

A colorant may be contained in the photocurable thermosetting resin composition. As the colorant, a known colorant such as red, blue, green, yellow, black, or white can be used, and any one of a pigment, a dye, and a colorant may be used. However, it is preferable not to contain halogen from the viewpoint of reducing the environmental load and affecting the human body.

The addition amount of the colorant is not particularly limited, but a ratio of preferably 10 parts by mass or less, particularly preferably 0.1 to 7 parts by mass, is sufficient with respect to 100 parts by mass of the alkali-soluble resin.

In addition, an elastomer can be incorporated into 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 polyester-based elastomers, polyurethane-based elastomers, polyesterurethane-based elastomers, polyamide-based elastomers, polyesteramide-based elastomers, acrylic-based elastomers, and olefin-based elastomers. In addition, a resin obtained by modifying some or all of the epoxy groups of an epoxy resin having various skeletons with carboxylic acid-modified butadiene-acrylonitrile rubber at both terminals can also be used. Epoxy-containing polybutadiene-based elastomers, acryl-containing polybutadiene-based elastomers, hydroxyl-containing polybutadiene-based elastomers, hydroxyl-containing isoprene-based elastomers, and the like can also be used. An elastomer may be used individually by 1 type, and may be used as a mixture of 2 or more types.

The addition amount of the elastomer 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, based on 100 parts by mass of the alkali-soluble 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 unlikely to be shortened.

Furthermore, components such as a block copolymer, an adhesion accelerator, an antioxidant, and an ultraviolet absorber can be further blended with the photocurable thermosetting resin composition as needed. These can use known ones in the field of electronic materials. In addition, at least any one of known and usual thickeners such as finely divided silica, hydrotalcite, organic bentonite and montmorillonite, antifoaming agents and leveling agents such as silicone-based, fluorine-based and polymer-based, imidazole-based, thiazole-based and triazole-based silanes At least any one of known and customary additives such as a coupling agent, a rust inhibitor, and an optical whitening 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, and petroleum solvents. 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 carbitol, butyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol ethers such as glycol monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, isobutyl acetate, ethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, and propylene glycol butyl ether acetate; alcohols such as ethanol, propanol, 2-methoxypropanol, n-butanol, isobutyl alcohol, isopentyl alcohol, 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, etc., N,N-dimethylformamide (DMF), tetrachloroethylene, turpentine, etc. are mentioned. In addition, Swarzol 1000 and Swarzol 1500 manufactured by Maruzen Sekiyu Kagaku Co., Ltd., Solveso 100 and Solveso 150 manufactured by Standard Sekiyu Osaka Hatsubaisha, Solvent #100 and Solvent #150 manufactured by Sankyo Kagaku Co., Ltd., and Shellsol manufactured by Shell Chemicals Japan Organic solvents such as A100, Shellsol A150, Ipsol No. 100 and Ipsol No. 150 manufactured by Idemitsu Kosan Co., Ltd. can also be used. These organic solvents may be used individually by 1 type, or may be used as a mixture of 2 or more types.

As a method for manufacturing a printed wiring board using a laminated film having a resin layer containing a photocurable thermosetting resin composition, a conventionally known method may be used. For example, when using the laminated|multilayer film which the (A) resin layer as shown in FIG. 2 sandwiches the (B) film and the (C) film, a printed wiring board can be manufactured by the following method. The (C) film is peeled off from the laminated film, (A) the resin layer is exposed, and the (A) resin layer of the laminated film is vacuum laminated under heating conditions on a substrate on which a circuit pattern is formed using a vacuum laminator or the like, (A) Pattern exposure is performed on a resin layer. (B) What is necessary is just to peel the film at any time point after lamination or after exposure. After that, alkali development is performed to form a patterned resin layer on the substrate, and the patterned resin layer is cured by light irradiation or heat to form a cured film, whereby a printed wiring board can be manufactured.

(thermosetting resin composition)

As an example of the thermosetting resin composition, a resin composition containing a thermosetting resin will be described below.

A thermosetting resin is a resin having a functional group capable of curing reaction by heat. The thermosetting resin is not particularly limited, and an epoxy compound, a multifunctional oxetane compound, a compound having two or more thioether groups in a molecule, that is, an episulfide resin, and the like can be used.

The said epoxy compound is a compound which has an epoxy group, and all conventionally well-known things can be used. A bifunctional epoxy compound having two epoxy groups in a molecule, a multifunctional epoxy compound having a plurality of epoxy groups in a molecule, and the like are exemplified. Moreover, a hydrogenated bifunctional epoxy compound may be used.

Examples of the epoxy compound include bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol S type epoxy resin, phenol novolak type epoxy resin, and cresol novolak. type epoxy resin, bisphenol A novolak type epoxy resin, biphenyl type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, triphenylmethane type epoxy resin, alicyclic epoxy resin, aliphatic Chain type epoxy resins, phosphorus-containing epoxy resins, anthracene type epoxy resins, norbornene type epoxy resins, adamantane type epoxy resins, fluorene type epoxy resins, aminophenol type epoxy resins, aminocresol type epoxy resins, alkylphenol type epoxy resins, etc. this is used These epoxy resins can be used individually by 1 type or in combination of 2 or more types.

The epoxy compound may be either a solid epoxy resin, a semi-solid epoxy resin, or a liquid epoxy resin. In the present specification, the solid epoxy resin means a solid epoxy resin at 40 ° C, the semi-solid epoxy resin means a solid epoxy resin at 20 ° C, and a liquid epoxy resin at 40 ° C, and the liquid epoxy resin means a liquid at 20 ° C. It means phosphorus epoxy resin. The liquid level is determined in accordance with Annex 2 “Liquid level confirmation method” of the Ministry Ordinance on Tests and Properties of Dangerous Substances (Ministry of Home Affairs Ordinance No. 1 in 1989).

A thermosetting resin can be used individually by 1 type or in combination of 2 or more types. The blending amount of the thermosetting resin is preferably 10 to 50% by mass, more preferably 10 to 40% by mass, and still more preferably 10 to 35% by mass, based on the total amount of the resin layer excluding the solvent. In the case of blending the liquid epoxy resin, the blending amount of the liquid epoxy resin is preferably 0 to 45% by mass based on the total mass of the thermosetting resin, since the glass transition temperature (Tg) and crack resistance of the cured product become better. , It is more preferable that it is 0-30 mass %, and it is especially preferable that it is 0-5 mass %.

The thermosetting resin composition may contain a filler, if necessary, in order to increase the physical strength and the like of the resulting cured product. Although there is no restriction|limiting in particular as a filler, For example, the filler illustrated with the said photocurable thermosetting resin composition 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 mixture of 2 or more types.

The thermosetting resin composition may 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.

In the curing agent, the ratio of a functional group capable of thermosetting reaction such as an epoxy group of a thermosetting resin and a functional group in the curing agent reacting with the functional group is such that the functional group of the curing agent/functional group capable of thermosetting reaction (equivalent ratio) = 0.2 to 2. It is preferable to blend with The roughening of the film surface in a desmear process can be prevented by carrying out the functional group / functional group (equivalent ratio) in which a thermosetting reaction of a hardening|curing agent is possible within the said range. 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 1.2.

The thermosetting resin composition may further contain a thermoplastic resin in order to improve the mechanical strength of the cured film obtained. It is preferable that the thermoplastic resin is soluble in a solvent. When it is soluble in a solvent, the flexibility of a dry film is improved, and generation|occurrence|production of a crack or falling-off of powder can be suppressed. As the thermoplastic resin, a thermoplastic polyhydroxypolyether resin, a phenoxy resin which is a condensate of epichlorohydrin and various bifunctional phenolic compounds, or a hydroxyl group present in the hydroxyether moiety present in the backbone thereof is used with various acid anhydrides or acid chlorides. Esterified phenoxy resin, polyvinyl acetal resin, polyamide resin, polyamideimide resin, block copolymer, etc. are mentioned. 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.

In addition, the thermosetting resin composition may contain rubber-like particles as needed. Examples of such rubbery particles include polybutadiene rubber, polyisopropylene rubber, urethane-modified polybutadiene rubber, epoxy-modified polybutadiene rubber, acrylonitrile-modified polybutadiene rubber, carboxyl-modified polybutadiene rubber, and acrylonitrile modified with carboxyl or hydroxyl groups. Butadiene rubber and crosslinked rubber particles thereof, core-shell type rubber particles, and the like are exemplified, and one type may be used alone or in combination of two or more types. These rubbery particles are added to improve the flexibility of the obtained cured film, improve crack resistance, enable surface roughening treatment with an oxidizing agent, and improve adhesion strength to copper foil or the like.

The average particle diameter 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 diameter of the rubber-like particles in the present invention can be measured using a dynamic light scattering method. For example, rubbery particles are uniformly dispersed in an appropriate organic solvent by ultrasonic waves or the like, and the particle size distribution of the rubbery particles is created on a mass basis using FPRA-1000 (manufactured by Otsuka Denshi Co., Ltd.), and the median diameter is It can be measured by setting it as an average particle diameter.

It is preferable that it is 0.5-10 mass %, and, as for the compounding quantity of rubber-like particle|grains, it is more preferable that it is 1-5 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 can be obtained and adhesion strength with a conductor pattern or the like can be improved. When it is 10% by mass or less, the coefficient of thermal expansion (CTE) is lowered, the glass transition temperature (Tg) is increased, and the curing properties are improved.

The thermosetting resin composition may contain a curing accelerator. The curing accelerator promotes the thermal curing reaction and is used to further improve 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; polyamines such as diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, melamine, and polybasic hydrazide; organic acid salts and/or epoxy adducts thereof; amine complexes of boron trifluoride; triazine derivatives such as ethyldiamino-S-triazine, 2,4-diamino-S-triazine, and 2,4-diamino-6-xylyl-S-triazine; Trimethylamine, triethanolamine, N,N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa(N-methyl)melamine, 2,4,6-tris(dimethylaminophenol), tetra amines such as methylguanidine and m-aminophenol; polyphenols such as polyvinylphenol, polyvinylphenol bromide, phenol novolac, and alkylphenol novolak; organic phosphines such as tributylphosphine, triphenylphosphine, and tris-2-cyanoethylphosphine; phosphonium salts such as tri-n-butyl(2,5-dihydroxyphenyl)phosphonium bromide and hexadecyltributylphosphonium chloride; quaternary ammonium salts such as benzyltrimethylammonium chloride and phenyltributylammonium chloride; the above polybasic acid anhydrides; photocationic polymerization catalysts such as diphenyliodonium tetrafluoroborate, triphenylsulfonium hexafluoroantimonate, and 2,4,6-triphenylthiopyrylium hexafluorophosphate; styrene-maleic anhydride resin; and conventionally known curing accelerators such as equimolar reactants of phenyl isocyanate and dimethylamine, equimolar reactants of organic polyisocyanates such as tolylene diisocyanate and isophorone diisocyanate and dimethylamine, and metal catalysts. Among the curing accelerators, phosphonium salts are preferable from the viewpoint of obtaining BHAST resistance.

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 in particular in the case of accelerating curing, it can be used in an amount of preferably 0.01 to 5 parts by mass per 100 parts by mass of the thermosetting resin. In the case of a metal catalyst, 10 to 550 ppm is preferable, and 25 to 200 ppm is preferable in terms of metal with respect to 100 parts by mass of the thermosetting resin.

The thermosetting resin composition, if necessary, conventionally known colorants such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, asbestos, orben, Conventionally known thickeners such as bentone and finely divided silica, antifoaming agents and/or leveling agents such as silicone, fluorine, and polymers, adhesion imparting agents such as thiazole, triazole, and silane coupling agents, flame retardants, titanate, and aluminum. Conventionally known additives can be further used.

As a method for manufacturing a printed wiring board using a laminated film having a resin layer containing a thermosetting resin composition, a conventionally known method may be used. For example, when using the laminated|multilayer film which the (A) resin layer as shown in FIG. 2 sandwiches the (B) film and the (C) film, a printed wiring board can be manufactured by the following method. The (C) film is peeled off from the laminated film and laminated on a circuit board on which a circuit pattern is formed using a vacuum laminator or the like under heating conditions, followed by thermal curing. Thermal curing can also be cured in an oven or by a hot plate press. When laminating or hot plate pressing the wiring board on which the circuit is formed and the laminated film of the present invention, the copper foil or the wiring board on which the circuit is formed may be simultaneously laminated. 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 a substrate on which a circuit pattern is formed, and exposing the circuit wiring. At this time, if there is a component (smear) remaining on the circuit wiring in the pattern or via hole that could not be completely removed, a desmear treatment is performed. (B) The film may be peeled at any time point after lamination, after thermal curing, after laser processing, or after desmear processing.

(Photo base generator-containing composition)

As an example of a composition containing a photobase generator, a composition containing an alkali developable resin, a heat-reactive component, and a photobase generator will be described below.

The alkali developable resin is a resin that contains at least one functional group from among a phenolic hydroxyl group, a thiol group, and a carboxyl group and can be developed with an alkaline solution, preferably a compound having two or more phenolic hydroxyl groups, a carboxyl group-containing resin, and a phenolic resin. The compound which has a hydroxyl group and a carboxyl group, and the compound which has two or more thiol groups are mentioned.

As the carboxyl group-containing resin, a known resin containing a carboxyl group can be used. The resin composition can be made alkali developable by the presence of a carboxyl group. In addition to the carboxyl group, a compound having an ethylenically unsaturated bond in the molecule can also be used, but in the present invention, only a carboxyl group-containing resin having no ethylenically unsaturated double bond is preferably used as the carboxyl group-containing resin.

As specific examples of the carboxyl group-containing resin, in addition to (1) to (11) exemplified as the carboxyl group-containing resin contained in the photocurable thermosetting resin composition, the compounds listed below (which may be either oligomers or polymers) are listed. can

(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, and polycarbonate-based polyols and polyethers Carboxyl group-containing by polyaddition reaction of diol compounds such as polyols, polyester polyols, polyolefin polyols, acrylic polyols, bisphenol A alkylene oxide adduct diols, compounds having phenolic hydroxyl groups and alcoholic hydroxyl groups urethane resin.

(13) Bifunctional epoxy resins such as diisocyanate, 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, and biphenol type epoxy resin A carboxyl group-containing urethane resin by a polyaddition reaction of a (meth)acrylate or a partially modified acid anhydride thereof, a carboxyl group-containing dialcohol compound, and a diol compound.

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

(15) During the synthesis of the resin of (12) or (13) above, an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate, etc., having one isocyanate group and one or more (meth)acryloyl groups in the molecule A carboxyl group-containing urethane resin obtained by adding a compound and carrying out terminal (meth)acrylation.

(16) A carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin with a saturated monocarboxylic acid to add a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, or hexahydrophthalic anhydride to a hydroxyl group present in a side chain. Here, it is preferable that the polyfunctional epoxy resin is solid.

(17) A polyester resin containing a carboxyl group obtained by reacting a polyfunctional oxetane resin with a dicarboxylic acid to add a dibasic acid anhydride to a first-class hydroxyl group generated.

(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 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 is reacted with a saturated monocarboxylic acid to form a polybasic acid anhydride with a reaction product obtained Carboxyl group-containing resin obtained by making it react.

(20) A reaction product obtained by reacting a saturated 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 Carboxyl group-containing resin obtained by making a polybasic acid anhydride react.

(21) 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 a cyclic carbonate compound such as ethylene carbonate or propylene carbonate.

(22) Reacting a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, such as p-hydroxyphenethyl alcohol, with an epoxy compound having a plurality of epoxy groups in one molecule, and a saturated monocarboxylic acid A carboxyl group-containing resin obtained by reacting polybasic acid anhydrides such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and adipic acid with respect to the alcoholic hydroxyl group of the obtained reaction product.

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

(24) In addition to any one of the resins (12) to (23) above, one epoxy group and one or more ( A carboxyl group-containing resin formed by adding a compound having a meth)acryloyl group.

Since the above alkali developable resin has many carboxyl groups, hydroxyl groups, etc. in the side chain of the backbone/polymer, development by aqueous alkali solution becomes possible.

In addition, the hydroxyl group equivalent or carboxyl group equivalent of the alkali developable resin is preferably 80 to 900 g/eq., more preferably 100 to 700 g/eq. A hydroxyl group equivalent or a carboxyl group equivalent of 900 g/eq. In the case of the following, the adhesiveness of a pattern layer is acquired and alkali image development becomes easy. On the other hand, if the hydroxyl group equivalent or the carboxyl group equivalent is 80 g/eq. In the case of the above, dissolution of the light-irradiated portion by the developing solution is suppressed, and a normal resist pattern is easily drawn without making the line thinner than necessary, which is preferable. Moreover, when the carboxyl group equivalent or the phenol group equivalent is large, it is preferable because image development becomes possible even when the content of the alkali developable resin is small.

It is preferable that the acid value of alkali developable resin is 40-150 mgKOH/g. By setting the acid value of the alkali developable resin to 40 mgKOH/g or more, alkali development becomes good. Further, 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 50-130 mgKOH/g.

The blending amount of the alkali developable 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 film strength can be improved by setting it as 20 mass % or more. Moreover, by setting it as 60 mass % or less, viscosity becomes moderate and applicability improves. More preferably, it is 30-50 mass %.

A heat-reactive compound is a resin having a functional group capable of curing reaction by heat. An epoxy resin, a polyfunctional oxetane compound, etc. are mentioned.

The said epoxy resin is resin which has an epoxy group, and all well-known things can be used. A bifunctional epoxy resin having two epoxy groups in a molecule, a multifunctional epoxy resin having a plurality of epoxy groups in a molecule, and the like are exemplified. Moreover, a hydrogenated bifunctional epoxy compound may be used.

It is preferable that the epoxy resin has an epoxy equivalent of 90 or more. When the epoxy equivalent is 90 or more, curvature of the cured film is suppressed, and developability is excellent even when left under high humidity for a long time.

As the blending amount of the heat-reactive compound, an equivalence ratio (heat-reactive group: alkali-developable group) with the alkali developable resin is preferably 1:0.1 to 1:10, more preferably 1:0.2 to 1:8. When within the range of such a compounding ratio, image development becomes favorable.

A photobase generator is a compound that generates at least one kind of basic substance capable of functioning as a catalyst for the addition reaction of the above-mentioned thermoreactive compound by changing its molecular structure or cleavage of the molecule by irradiation with light such as ultraviolet rays or visible light. am. As a basic substance, a secondary amine and a tertiary amine are mentioned, for example.

As the photobase generator, for example, an α-aminoacetophenone compound, an oxime ester compound, an acyloxyimino group, an N-formylated aromatic amino group, an N-acylated aromatic amino group, a nitrobenzylcarbamate group, an alkoxybenzyl car and compounds having substituents such as a barmate group.

The said photobase generator may be used individually by 1 type, and may be used in combination of 2 or more type. The blending amount of the photobase generator in the composition containing the photobase generator is preferably 1 to 50 parts by mass, more preferably 1 to 40 parts by mass, based on 100 parts by mass of the heat-reactive compound. In the case of 1 mass part or more, since image development becomes easy, it is preferable.

A filler may be added to the photobase generator-containing composition as necessary in order to increase the physical strength and the like of the resulting cured product. Although there is no restriction|limiting in particular as a filler, For example, the filler illustrated with the said photocurable thermosetting resin composition 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 mixture of 2 or more types.

Components such as a mercapto compound, an adhesion accelerator, an antioxidant, and an ultraviolet absorber can be further blended with the photobase generator-containing composition as needed. Those known in the field of electronic materials can be used.

In addition, in the photobase generator-containing composition described above, known and usual thickeners such as finely divided silica, hydrotalcite, organic bentonite, and montmorillonite, silicone-based, fluorine-based, and polymer-based antifoaming agents and/or leveling agents, silane coupling agents, and rust preventives Known and customary additives such as the like can be blended.

As a method for producing a printed wiring board using a laminated film having a resin layer containing a photobase generator-containing composition, a conventionally known method may be used. For example, when using the laminated|multilayer film which the (A) resin layer as shown in FIG. 2 sandwiches the (B) film and the (C) film, a printed wiring board can be manufactured by the following method. The (C) film is peeled off from the laminated film, the (A) resin layer is exposed, and the (A) resin layer of the laminated film is vacuum laminated on the substrate on which the circuit pattern is formed using a vacuum laminator or the like under heating conditions. Thereafter, the photobase generator contained in the photobase generator-containing resin composition is activated by irradiation with light on a negative pattern to cure the light irradiated portion, and the unirradiated portion is removed by alkali development to form a negative pattern layer. can do. (B) What is necessary is just to peel the film at any time point after lamination or after exposure. Moreover, it is preferable to heat the (A) resin layer after light irradiation and before image development. Thereby, (A) the resin layer can be fully cured, and a pattern layer with further excellent curing properties can be obtained. In addition, it is preferable that the heating after light irradiation and before development is a temperature at which the unirradiated portion is not thermally cured. Further, it is preferable to perform thermal curing (post-curing) after development. After image development, by performing ultraviolet irradiation, after activating the remaining photobase generator without being activated at the time of light irradiation, thermal curing (post-curing) can also be performed.

(Positive photosensitive thermosetting resin composition)

As an example of the positive photosensitive thermosetting resin composition, a resin composition containing a compound that generates a carboxyl group by light irradiation will be described below.

Among the compounds that generate a carboxyl group upon irradiation with light, it is preferable to use a naphthoquinonediazide compound. Conventionally, a naphthoquinonediazide compound is used in a system in which alkali solubility of a carboxyl group or the like is suppressed by forming a complex with a carboxyl group or a phenolic hydroxyl group, and then the complex is dissociated by light irradiation to express alkali solubility. In this case, if the naphthoquinonediazide compound remains in the film, the complex is dissociated by light irradiation and solubility may be expressed. Therefore, in the semiconductor field, etc., the remaining naphthoquinonediazide compound is finally It was removed by volatilization at high temperature. However, in the field of printed wiring boards, naphthoquinonediazide compounds have not been practically used because such high temperatures are not applied and cannot be used as permanent coatings from the viewpoint of stability. In the present invention, when a naphthoquinonediazide compound is used as a compound that generates a carboxyl group by light irradiation, the naphthoquinonediazide compound remaining in the unexposed area is introduced into the crosslinked structure during the thermal curing reaction and stabilized. , the conventional problem of removal does not occur, and the film toughness, that is, bending resistance and electrical properties can be improved. In particular, by using a naphthoquinonediazide compound as a compound that generates a carboxyl group by light irradiation in combination with a polyamideimide resin and a thermosetting component, it is possible to effectively improve flexibility while ensuring good developability and resolution. be, it is desirable

As a naphthoquinonediazide compound, specifically, for example, a naphthoquinonediazide adduct of tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene (for example, Sanbo Chemical Co., Ltd.) TS533, TS567, TS583, TS593 manufactured by Kyusho Co., Ltd.) and naphthoquinonediazide adducts of tetrahydroxybenzophenone (eg, BS550, BS570, BS599 manufactured by Sanbo Chemical Co., Ltd.) can be used.

A filler can be blended with the positive photosensitive thermosetting resin composition as needed in order to raise the physical strength and the like of the cured product to be obtained. Although there is no restriction|limiting in particular as a filler, For example, the filler illustrated with the said photocurable thermosetting resin composition 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 resins exemplified in the photocurable thermosetting resin composition and the alkali developable resins exemplified in the photobase generator-containing composition.

A thermosetting component may be contained in the positive photosensitive thermosetting resin composition for the purpose of improving properties such as heat resistance and insulation reliability. Examples of the thermosetting component include isocyanate compounds, block isocyanate compounds, amino resins, maleimide compounds, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, polyfunctional epoxy compounds, polyfunctional oxetane compounds, episulfide resins, etc. A well-known and commonly used thermosetting resin can be used. Among these, a preferable thermosetting component is a thermosetting component having a plurality of cyclic ether groups and/or cyclic thioether groups (hereinafter abbreviated as cyclic (thio) ether groups) in one molecule. There are many types of thermosetting components having a cyclic (thio)ether group on the market, and various properties can be imparted depending on their structures.

The compounding amount of the thermosetting component having a plurality of cyclic (thio)ether groups in the molecule is preferably 0.3 to 2.5 equivalents, more preferably 0.5 to 2.0 equivalents, relative to 1 equivalent of the carboxyl group of the photosensitive resin containing a carboxyl group. By setting the compounding amount of the thermosetting component having a plurality of cyclic (thio)ether groups in the molecule to 0.3 equivalent or more, no carboxyl group remains in the cured film, and heat resistance, alkali resistance, electrical insulation, etc. are improved. Moreover, by setting it as 2.5 equivalent or less, a low molecular weight cyclic (thio) ether group does not remain|survive in a dry coating film, but the intensity|strength of a cured film etc. improves.

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 mixture of 2 or more types.

The positive photosensitive thermosetting resin composition may contain other components, such as a block copolymer, a filler, a colorant, an elastomer, and a thermoplastic resin, in addition to the above components. Moreover, components, such as an adhesion accelerator, an antioxidant, and a ultraviolet absorber, can be further mix|blended with the positive type photosensitive thermosetting resin composition as needed. These can use known ones in the field of electronic materials. In addition, at least any one of known and usual thickeners such as finely divided silica, hydrotalcite, organic bentonite and montmorillonite, antifoaming agents and leveling agents such as silicone-based, fluorine-based and polymer-based, imidazole-based, thiazole-based and triazole-based silanes At least any one of known and customary additives such as a coupling agent, a rust inhibitor, and an optical whitening agent can be blended.

As a method for manufacturing a printed wiring board using a laminated film having a resin layer containing a positive photosensitive thermosetting resin composition, a conventionally known method may be used. For example, when using the laminated|multilayer film which the (A) resin layer as shown in FIG. 2 sandwiches the (B) film and the (C) film, a printed wiring board can be manufactured by the following method. The (C) film is peeled off from the laminated film, the (A) resin layer is exposed, and the (A) resin layer of the laminated film is vacuum laminated on the substrate on which the circuit pattern is formed using a vacuum laminator or the like under heating conditions. Then, (A) a positive pattern layer can be formed by irradiating the resin layer with light in a positive pattern form, subjecting the resin layer to alkali development, and removing the light irradiation portion. (B) What is necessary is just to peel the film at any time point after lamination or after exposure. In addition, a printed wiring board can be manufactured by heat-hardening (post-curing) a resin layer after image development, and hardening an unirradiated part. In the positive photosensitive thermosetting resin composition, the acid generated by light irradiation changes the composition to a composition soluble in an alkali developing solution, so that positive pattern formation by alkali development becomes possible.

[(B) Film]

In the laminated film of the present invention, the (B) film has a 5% elongation load per unit width at 80°C of more than 90 g/mm and not more than 500 g/mm. When laminating a laminated film having a resin layer sandwiched between a support film and a protective film, in many cases, the protective film is peeled off and laminated so that the surface of the resin layer in contact with the protective film is in contact with the wiring board. 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 is in contact with the wiring board. In the present invention, since the surface of the (A) resin layer on the opposite side to the (B) film can be laminated on the wiring board so that the surface is in contact with the wiring board, the (B) film has a 5% elongation load per unit width at 80 ° C. Any of a support film and a protective film may be sufficient as long as it is a film of more than 90 g/mm and 500 g/mm or less. Preferably, the (B) film is a supporting film.

A support film has a role of supporting the resin layer of a laminated film, and is a film to which a resin composition is applied when forming the resin layer. Examples of the support film include thermoplastic resins such as polyester films such as polyethylene terephthalate and polyethylene naphthalate, polyimide films, polyamideimide films, polyethylene films, polytetrafluoroethylene films, polypropylene films, and polystyrene films. A containing film and surface-treated paper, etc. can be used. Among these, from viewpoints of heat resistance, mechanical strength, handleability, etc., a polyester film can be used suitably. The thickness of the support film is not particularly limited, but is appropriately selected depending on the application in the range of about 10 to 150 μm. Release treatment may be performed on the surface of the support film on which the resin layer is provided. In addition, sputtering or ultra-thin 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 dirt and the like from adhering to the surface of the resin layer of the laminated film and improving handling properties. As the protective film, for example, a film containing the thermoplastic resin exemplified in the support film and paper subjected to surface treatment can be used, but 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 application in the range of about 10 to 150 μm. Release treatment may be given to the surface on which the resin layer of the protective film is formed.

(B) As the film, a commercially available film having a 5% stretch load per unit width at 80°C of more than 90 g/mm and 500 g/mm or less can also be used. For example, Diafoil R310 by Mitsubishi Corporation, Lumirror T6AM by Toray, Toyobo Ester Film E5041 by Toyobo, Emblem PTHA by Unitica, etc. are mentioned.

((C) Film)

(C) As a film, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a polyethylene naphthalate (PEN) film etc. can be used, for example. When laminating the (A) resin layer to the substrate, considering the peeling of the (C) film, the adhesive force between the (A) resin layer and the (C) film is smaller than the adhesive force between the (A) resin layer and the (B) film. It is desirable to keep In addition, the film illustrated in the illustration of the (B) film can also be used as the (C) film. (C) The film is preferably a protective film.

The laminated film of the present invention can be preferably used for forming a permanent protective film of a printed wiring board, and, among others, can be preferably used for forming a solder resist layer, an interlayer insulating layer, and a coverlay for a flexible printed wiring board. Moreover, the laminated|multilayer film of this invention can also form a wiring board by joining wiring. Moreover, it can be used also as sealing resin for semiconductor chips.

The laminated film of the present invention can be suitably used because wrinkles are unlikely to occur in the resin layer even when vacuum lamination is employed under heating conditions, for example, at 40 to 160° C. as a method for adhering the laminated film. . The heating conditions are preferably 50 to 150°C, more preferably 50 to 130°C. Further, from the viewpoint of circuit conformability, it can be suitably used for formation of a printed wiring board having a circuit in a fine pattern in which vacuum lamination is employed under heating conditions. After laminating the laminated film of the present invention on a wiring board, it is preferable to perform a flattening treatment by hot pressing. The hot press is performed at, for example, 40 to 160°C, preferably 50 to 150°C, and more preferably 50 to 130°C.

<Example>

Hereinafter, examples, comparative examples and test examples of the present invention will be described and the present invention will be described in detail, 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 Carboxyl Group-Containing Resin A-1)

Into an autoclave equipped with a thermometer, a nitrogen introduction device, an alkylene oxide introduction device, and a stirring device, 119.4 g of a novolak type cresol resin (Shonol CRG951 manufactured by Showa Denko, OH equivalent: 119.4), 1.19 g of potassium hydroxide, and 119.4 toluene g was added, and the inside of the system was substituted with nitrogen while stirring, and the temperature was raised by heating. Next, 63.8 g of propylene oxide was gradually added dropwise and reacted at 125 to 132°C and 0 to 4.8 kg/cm 2 for 16 hours. Thereafter, the reaction solution was cooled to room temperature, and potassium hydroxide was neutralized by adding and mixing 1.56 g of 89% phosphoric acid to the reaction solution to obtain propylene oxide of a novolac-type cresol resin having a non-volatile content of 62.1% and a hydroxyl value of 182.2 g/eq. A reaction solution was obtained. The obtained novolak-type cresol resin had an average of 1.08 mol of alkylene oxide added per equivalent of phenolic hydroxyl group.

293.0 g of the obtained alkylene oxide reaction solution of the novolak-type cresol resin, 43.2 g of acrylic acid, 11.53 g of methanesulfonic acid, 0.18 g of methylhydroquinone, and 252.9 g of toluene were put into a reactor equipped with a stirrer, a thermometer and an air intake pipe, , Air was blown in at a rate of 10 ml/min and reacted at 110°C for 12 hours while stirring. 12.6 g of water distilled out of the water produced|generated by reaction as an azeotropic mixture with toluene. Thereafter, the reaction solution obtained by cooling to room temperature was neutralized with 35.35 g of a 15% sodium hydroxide aqueous solution, followed by washing with water. Thereafter, distillation was carried out while replacing toluene with 118.1 g of diethylene glycol monoethyl ether acetate in an evaporator to obtain a novolak-type acrylate resin solution. Then, 332.5 g of the obtained novolak-type acrylate resin solution and 1.22 g of triphenylphosphine were put into a reactor equipped with a stirrer, a thermometer and an air suction pipe, air was blown in at a rate of 10 ml/min, and while stirring, 62.3 g of hydrophthalic anhydride was added gradually, and it was made to react at 95-101 degreeC for 6 hours, and the resin solution of the carboxyl group-containing photosensitive resin as solid content 71% of solid content acid value 88 mgKOH/g was obtained. Hereinafter, this is called varnish A-1.

(Synthesis of Carboxyl Group-Containing Resin A-2)

600 g of diethylene glycol monoethyl ether acetate, 1070 g of orthocresol novolak type epoxy resin (manufactured by DIC, EPICLON N-695, softening point 95 ° C, epoxy equivalent 214, average functional group number 7.6) (glycidyl group number (direction) Total number of 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 dissolve uniformly. Subsequently, 4.3 g of triphenylphosphine was introduced, heated at 110°C and reacted for 2 hours, then heated at 120°C and reacted again for 12 hours. 415 g of aromatic hydrocarbons (Solveso 150) and 456.0 g (3.0 mol) of tetrahydrophthalic anhydride were added to the obtained reaction liquid, reacted at 110°C for 4 hours, and cooled. In this way, a resin solution having a solid acid value of 89 mgKOH/g and a solid content of 65% was obtained. Hereinafter, this is called varnish A-2.

(Adjustment of photosensitive resin composition)

According to the formulation shown in the table below, each component was blended and premixed with a stirrer, then dispersed and kneaded with a 3-roll mill to prepare the first and second solutions. The obtained first liquid and the second liquid were blended to prepare photosensitive resin compositions I to V. The compounding quantity in a table|surface shows a mass part.

A-1: Carboxyl group-containing resin varnish obtained above A-1

A-2: Carboxyl group-containing resin varnish A-2 obtained above

*1: C.I. Pigment Blue 15:3

*2: C.I. Pigment Yellow 147

*3: IRGANOX 1010: manufactured by BASF Japan

*4: 2-mercaptobenzothiazole (Axel M: manufactured by Kawaguchi Chemical Industry Co., Ltd.)

*5: Silica

*6: Barium sulfate (B-30: manufactured by Sakai Chemical Co., Ltd.)

*7: Talc (SG-2000: manufactured by Nippon Talc Co., Ltd.)

*8: Hydrotalcite (DHT-4A: manufactured by Kyowa Chemical Industry Co., Ltd.)

*9: 1-methoxypropyl-2-acetate

*10: dipentaerythritol hexaacrylate

*11: Biphenyl novolac type epoxy resin (NC3000HCA75: manufactured by Nippon Kayaku Co., Ltd.: softening point 70°C)

*12: Bixylenol type epoxy resin (YX-4000: manufactured by Mitsubishi Chemical Corporation: melting point 105 ° C.)

*13: Phenol novolac type epoxy resin (RE306CA90: manufactured by Nippon Kayaku Co., Ltd.: softening point 50°C)

*14: 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one (Irgacure 907: manufactured by BASF Japan)

*15: 2,4-Diethylthioxanthone (KAYACURE DETX-S: manufactured by Nippon Kayaku Co., Ltd.)

*16: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (Lucirin TPO: manufactured by BASF Japan)

*17: Ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1-(0-acetyloxime) (Irgacure OXE02: manufactured by BASF Japan) )

*18: Diethylene glycol monoethyl ether acetate

(Measurement of Melt Viscosity of Resin Layer Material)

A mixed dilution solution obtained by diluting the photosensitive resin compositions I to V obtained above with methyl ethyl ketone was applied to a polyethylene terephthalate film having a thickness of 25 μm using a 90 μm applicator and dried at 80 ° C. for 15 minutes to obtain a resin layer 1 to V got A sample having a thickness of 300 μm was formed by peeling and overlapping films from the obtained resin layers I to V. Using this sample, using Rheo Stress RS-6000 (manufactured by HAAKE), oscillation mode, stress control method, heating rate 5 ° C / min, control stress 3 Pa, gap 260 μm, frequency Melt viscosity at 80°C was measured under conditions of 1 Hz. The results are shown in Table 2.

(Measurement of 5% elongational load (EL80 value) per unit width at 80°C of film)

The (B) film shown in Table 3 below was cut into a rectangle with a length of 50 mm and a width of 3 mm, installed at room temperature in TA's RSA-G2 with a chuck interval of 30 mm, and after maintaining the temperature at 80 ° C., a tensile speed of 30 A tensile test was performed at mm/min, and the value obtained by dividing the load when the sample exhibited an elongation of 5% by the width of the sample was taken as the EL80 value (g/mm). The test was performed five times each in the longitudinal and transverse directions of the film, and the second value from the maximum was recorded as the maximum value, and the second value from the minimum was recorded as the minimum value.

(Manufacture of laminated film)

On the (B) film shown in Table 3 below, a diluted mixed solution obtained by diluting the photosensitive resin composition obtained above with methyl ethyl ketone was applied so that the thickness after drying was 20 μm, and dried with warm air at 80 ° C. for 15 minutes to obtain a photosensitive (A) ) to obtain a resin layer. Subsequently, as the film (C), a biaxially stretched polypropylene film (manufactured by Oji Alpan Co., Ltd., MA) having a thickness of 15 μm was laminated on the resin layer (A) to prepare a laminated film. The obtained laminated film was wound so that the (C) film was outside, and it was set as the laminated film of Examples 1-8 and Comparative Example 1.

(Preparation of evaluation substrate a for evaluation of adhesion performance)

A circuit pattern substrate having a copper thickness of 25 μm and a minimum width between circuits of 100 μm was subjected to a copper surface roughening treatment using Mack Etch Bond CZ-8101 manufactured by Mack Corporation, then washed with water and dried. Laminated films of Examples 1 to 8 and Comparative Example 1 were applied to the obtained dry substrate using a vacuum laminator (CVP-300: manufactured by Nichigo Morton Co., Ltd.) in a first chamber at a temperature of 80° C. at a vacuum pressure of 3 hPa and a vacuum time of 30 seconds. After laminating under vacuum under conditions, press was performed under conditions of a press pressure of 0.5 MPa and a press time of 30 seconds to prepare an evaluation substrate a for adhesive performance evaluation.

(Preparation of evaluation substrate b for evaluation of adhesion performance)

The evaluation substrate a for evaluation of adhesion performance prepared above was flattened by pressing with a stainless plate for 60 seconds at a press pressure of 8 kgf/m2 in a second chamber at a temperature of 80°C, and evaluated for adhesion performance evaluation. Substrate b was produced.

(Evaluation of wrinkles after vacuum lamination under heating conditions)

The presence or absence of wrinkles on the surface of the evaluation substrate a for evaluation of adhesive performance produced above was visually confirmed through the (B) film, and evaluation was performed according to the following criteria. Evaluation was performed 5 times. The results are shown in Table 2.

○: No occurrence of wrinkles on all evaluation boards

×: occurrence of wrinkles with a length of 1 cm or more in one or more evaluation boards

(Evaluation of wrinkles after flattening treatment by heat press)

The presence or absence of wrinkles on the surface of the evaluation substrate b for evaluation of adhesive performance produced above was visually confirmed through the (B) film, and evaluation was performed according to the following criteria. Evaluation was performed 5 times. The results are shown in Table 2.

○: No occurrence of wrinkles on all evaluation boards

×: occurrence of wrinkles with a length of 1 cm or more

(Preparation of Evaluation Substrate c for Evaluation of Adhesion Performance)

A substrate c for evaluation was produced by exposing the entire surface using an exposure apparatus equipped with a high-pressure mercury-vapor lamp with respect to the substrate produced by the same method as the evaluation substrate b, except that a copper solid substrate having a plate thickness of 0.8 mm was used.

(auto filler test)

Using the evaluation board c, the (B) film was peeled with a film peeling device for printed circuit boards manufactured by Hitachi Plant Mechanics under conditions of a cutting roll pressure of 0.4 MPa, a peeling tape pressing pressure of 0.4 MPa, and a peeling speed of 15 m/min, and the following Evaluation was conducted under the conditions. Evaluation was performed 5 times.

○: The (B) film can be peeled off from the resin layer in all evaluation substrates.

×: (B) The film is torn and remains in the (A) resin layer after photosensitization

(Preparation of evaluation substrate d for evaluation of cured product properties)

The evaluation substrate b for evaluation of adhesion performance produced above was exposed through a step tablet (Kodak No. 2) using an exposure apparatus equipped with a high-pressure mercury lamp. Development (30 ° C., 0.2 MPa, 1% by mass sodium carbonate aqueous solution) was performed for 90 seconds, the exposure amount when the pattern of the remaining step tablet was 7 steps was set as the optimal exposure amount, and a pattern-like cured product was formed at the optimal exposure amount. This substrate was irradiated with ultraviolet rays in a UV conveyor furnace under conditions of a cumulative exposure of 1000 mJ/cm 2 , and then cured by heating at 150° C. for 90 minutes to evaluate characteristics of a cured product having a patterned cured product. An evaluation substrate d was prepared.

(Resolution)

An evaluation board b' was produced in the same way as the evaluation board b for evaluating adhesive performance, except that a full-surface copper-clad laminate board was used instead of the circuit pattern board having a copper thickness of 25 μm and a minimum inter-circuit width of 100 μm. With respect to this produced evaluation board|substrate b', the evaluation board|substrate e for hardened|cured material property evaluation was produced similarly to the evaluation board|substrate d for hardened|cured material property evaluation except having used the opening pattern of 150 micrometers as an opening pattern. The opening shape of the evaluation board|substrate e for characteristic evaluation of the produced hardened|cured material was observed with the SEM (scanning electron microscope), and it evaluated based on the following criteria. Evaluation was performed 5 times. The results are shown in Table 2.

○: A stable aperture shape was obtained without halation and undercut

×: Halation or undercut occurred and a stable aperture shape was not obtained.

(solder heat resistance)

After applying the rosin-based flux to the evaluation substrate d for evaluating the properties of the cured product prepared above, it was immersed in a solder bath set at 260°C in advance. Then, after washing the flux with denatured alcohol, expansion and peeling of the resist layer was visually observed and evaluated according to the following criteria. The results are shown in Table 2.

◎: No peeling of the resist layer was observed even after immersion for 10 seconds was repeated 4 times or more.

○: Even if immersion is repeated twice for 10 seconds, peeling is not observed in the resist layer.

×: Swelling and peeling in the resist layer within 1 time of immersion for 10 seconds

*19: Diafoil R310 (polyethylene terephthalate film) manufactured by Mitsubishi Corporation

*20: Toray Lumirror T6AM (polyethylene terephthalate film)

*21: Toyobo Ester Film E5041 (polyethylene terephthalate film) manufactured by Toyobo Co., Ltd.

*22: Emblem PTHA (polyethylene terephthalate film) manufactured by Unitica Co., Ltd.

*23: Toray Lumiror 12F68 (polyethylene terephthalate film)

From the results shown in Table 3, in the case of the laminated films of the examples, wrinkles are less likely to occur even after vacuum lamination under heating conditions, and the film does not remain on the resin layer even if the film is peeled off with an auto filler. It can be seen that it is difficult to remain. On the other hand, in the case of Comparative Example 1 using a film having a 5% stretch load per unit width at 80°C that does not satisfy more than 90 g/mm and less than or equal to 500 g/mm, wrinkles are generated after vacuum lamination under heating conditions, and the film at the wrinkle portion is not satisfied. Deterioration in resolution and solder heat resistance due to a decrease in thickness was observed, and it was found that the film remained on the resin layer when the film was peeled off with an auto filler.

(A) Resin layer
(B) A film having a 5% elongational load per unit width at 80°C of greater than 90 g/mm and not greater than 500 g/mm
(C) film

Claims (7)

A laminated film in which (A) a resin layer and (B) a polyethylene terephthalate film having a 5% elongation load per unit width at 80 ° C. of more than 90 g / mm and less than or equal to 500 g / mm are laminated,
The (A) resin layer has a melt viscosity at 80 ° C. of 10 to 10000 dPa s,
The (A) resin layer is a photosensitive resin layer containing a carboxyl group-containing resin, a photopolymerization initiator, a compound having an ethylenically unsaturated bond, a thermosetting resin, and a filler,
The (B) polyethylene terephthalate film is a peelable layer that can be peeled from the (A) resin layer,
The (B) 5% extension load per unit width at 80°C is obtained by heating and holding a rectangular sample of the polyethylene terephthalate film (B) having a length of 50 mm and a width of 3 mm at a temperature of 80°C and maintaining the tensile speed at a rate of 30 mm. A multilayer film characterized by being a value obtained by dividing a load obtained by performing a tensile test at /min and exhibiting an elongation of 5% of the sample by the width of the sample. The laminated film according to claim 1, characterized in that it is used by adhering to a surface of a wiring board. The laminated film according to claim 2, characterized in that it is bonded to the surface of the wiring board using a vacuum laminator. The laminated film according to claim 3, characterized in that the laminate film is bonded to the surface of the wiring board by a lamination process using a vacuum laminator followed by a flattening process by a hot press. The laminated film according to any one of claims 1 to 4, which is used for forming a permanent film on a wiring board. delete delete

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