Laminates, cured products, and electronic components

Abstract

The present invention provides laminates and the like that do not experience the problem of resin layer separation even when slitting is performed continuously. [Solution] A laminate comprising a first film and a resin layer, characterized in that the tensile modulus of the first film is 1.0 GPa to 5.0 GPa and the storage modulus of the resin layer is 0.05 MPa to 3.0 MPa.

Description

Technical Field

[0001] The present invention relates to a laminate, a cured product, and an electronic component.

Background Art

[0002] Conventionally, as one of the forming means for protective films and insulating layers such as solder resists and interlayer insulating layers provided on printed wiring boards used in electronic devices and the like, a dry film (hereinafter, may be simply referred to as "laminate" in this specification) has been used (for example, Patent Document 1). A dry film has a resin layer obtained through a drying process after applying a resin composition having desired properties on a first film (also referred to as a "carrier film"). Generally, it is distributed on the market in a state where a second film (also referred to as a "protective film") for protecting the surface opposite to the first film is further laminated. After adhering the resin layer of the dry film to a substrate (hereinafter also referred to as "laminating"), by performing patterning and curing treatment, a printed wiring board having the above-described protective film and insulating layer can be manufactured.

[0003] The second film is to be removed from the resin layer when laminating the dry film to the substrate. Conventionally, in the manufacturing process of the dry film, the conditions are adjusted so that the peel strength of the second film with respect to the resin composition becomes small so that the resin composition does not transfer to the second film (hereinafter also referred to as "weeping separation of the resin layer"). Patent Document 2 discloses an adhesive sheet with a second film in which resin peeling does not occur when the second film is peeled, and the peel strength of the second film is 0.0020 kgf / cm or less than the peel strength of the first film. 2 The above-described adhesive sheet with a second film is disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] The three-layer dry film having a second film and a first film is typically manufactured by first applying a curable resin composition to the first film after adjusting its viscosity by the amount of solvent, then drying it in a drying oven to form a resin layer on the first film, and then laminating the second film to the surface of the resin layer opposite to the first film. The shape of the long dry film is, for example, 1 m wide and 1000 m long, and it is in the form of a roll.

[0006] Long lengths of dry film are slit (cut) according to the required length and width, for example, to adjust the width to 50 cm to become dry film. However, when slitting continuously over a length of 1000 m, as described above, the conventional combination of the first film and resin layer of dry film, especially in the case of a highly elastic resin layer, is subjected to impact during cutting, which can cause the resin layer to separate during lamination.

[0007] Therefore, the object of the present invention is to provide a laminate in which the problem of separation of the resin layer does not occur even when slitting is performed continuously, a cured product obtained by curing the resin layer of the laminate, and an electronic component having the cured product. [Means for solving the problem]

[0008] The inventors conducted diligent research and found that the above problems could be solved by a laminate in which the tensile modulus of the first film and the storage modulus of the resin layer satisfy certain conditions, thus completing the present invention. Specifically, the laminate of the present invention is a laminate comprising a first film and a resin layer, characterized in that the tensile modulus of the first film is 1.0 GPa to 5.0 GPa and the storage modulus of the resin layer is 0.05 MPa to 3.0 MPa.

[0009] In this invention, the tensile modulus of the first film is measured and calculated using an RSA-G2 manufactured by TA Instruments, Inc., in accordance with the procedure described below, in accordance with JIS K 7161-1:2014, which specifies the method for determining the tensile properties of plastics. <Method for measuring and calculating the tensile modulus of the first film> First, 3 mm wide test pieces are cut from each of the first films in both the TD direction (longitudinal direction of the film) and the MD direction (width direction of the film). Each obtained test piece is subjected to a tensile test at 25°C, with a grip distance of 10 mm, constant velocity movement at a tensile speed of 0.002 mm / sec (0.12 mm / min), and load measurement conditions. The tensile modulus of the first film in each TD and MD direction is determined from the slope of the regression line drawn at elongation rates of 0.05% to 0.25% in the elongation-stress curve obtained from the tensile test. Specifically, it is calculated based on the following formula 1. Then, the average value of the modulus of elasticity in each TD and MD direction is calculated and taken as the tensile modulus of the first film. TIFF2026109383000002.tif24165

[0010] In rare cases, there are first films in which the TD direction (longitudinal direction of the film) and MD direction (width direction of the film) are unknown. In such cases, these can be confirmed by measuring the "molecular orientation angle relative to the TD direction" using a simple method using two polarizing plates or a phase difference measuring device (for example, a polarizing microscope or KOBRA-21ADH manufactured by Oji Instruments Co., Ltd.) as described in Japanese Patent Application Publication No. 2024-110224 (paragraph 0026). Furthermore, the tensile modulus of the first film may be measured before laminating the resin layer, or it may be measured after peeling the first film off the laminate.

[0011] Furthermore, in this invention, the storage modulus of the resin layer is measured using a rheometer HAAKE MARS40 (manufactured by Thermo Fisher) under the following conditions: sensor parallel plate φ20 mm, strain 0.001-1%, oscillation mode at frequency 1 Hz, and temperature 30°C.

[0012] The laminate of the present invention is preferably obtained from a curable resin composition comprising a photocurable resin, a thermosetting resin, a photopolymerization initiator, and an inorganic filler, wherein the thickness of the first film is preferably 20 μm to 100 μm, and further preferably the curable resin composition contains 20% to 70% by mass of the inorganic filler on a solid content basis, and more preferably the inorganic filler contains silica.

[0013] The cured product of the present invention is characterized by having been obtained by curing the resin layer of the laminate of the present invention.

[0014] The electronic component of the present invention is characterized by having the cured product of the present invention. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide a laminate in which the problem of separation of the resin layer does not occur even when slitting is performed continuously, a cured product obtained by curing the resin layer of the laminate, and an electronic component having the cured product. [Brief explanation of the drawing]

[0016] [Figure 1] This is a schematic cross-sectional view illustrating one embodiment of the laminate of the present invention. [Figure 2] This is a schematic cross-sectional view illustrating another embodiment of the laminate of the present invention. [Modes for carrying out the invention]

[0017] <Laminate> Fig. 1 shows a schematic cross-sectional view of an embodiment of the laminate of the present invention. In the laminate 11 of the present invention, a resin layer 12 is formed on a first film 13. Fig. 2 shows a laminate of another embodiment of the present invention, which is a schematic cross-sectional view of a general embodiment during the above-mentioned market circulation. The laminate 21 of the present invention has a structure in which a resin layer 22 is formed on a first film 23, and a second film 24 is further laminated on the resin layer 22. The laminate of the present invention is a laminate comprising a first film and a resin layer, wherein the tensile modulus of elasticity of the first film is 1.0 GPa to 5.0 GPa, and the storage modulus of elasticity of the resin layer is 0.05 MPa to 3.0 MPa.

[0018] If the tensile modulus of elasticity of the first film is 1.0 to 5.0 GPa, the impact during film cutting that causes separation can be alleviated, and the effect of suppressing separation can be obtained. Preferably, it is 3.0 to 5.0 GPa, more preferably 4.0 to 5.0 GPa, and even more preferably 4.0 to 4.8 GPa.

[0019] If the storage modulus of elasticity of the resin layer is 0.05 MPa or more, sufficient dissociability from the first film and the second film can be obtained. Also, if it is 3.0 MPa or less, cracks during film cutting that trigger separation are less likely to occur, and the effect of suppressing separation can be obtained. Preferably, it is 2.5 MPa or less, more preferably 2.0 MPa or less, and even more preferably 1.5 MPa or less. By appropriately adjusting the types and blending amounts of the thermosetting resin, photocurable resin, and inorganic filler, a suitable storage modulus of elasticity of the resin layer can be achieved.

[0020] Hereinafter, each component of the present invention will be described in detail.

[0021] [Resin layer] The resin layer of the laminate of the present invention is generally in a state called the B-stage state and is obtained from a curable resin composition. Specifically, it is obtained by applying the curable resin composition to a first film and then passing it through a drying process. The thickness of the resin layer is not particularly limited, but is preferably 5 μm to 100 μm. If it is 5 μm or more, the effect of suppressing separation can be obtained, but it is preferably 10 μm or more, and more preferably 15 μm or more. Also, if it is 100 μm or less, good resolution can be obtained, but it is preferably 50 μm or less, more preferably 40 μm or less, and even more preferably 30 μm or less.

[0022] [Curable resin composition] The curable resin composition used to form the resin layer of the present invention contains a thermosetting resin and / or a photocurable resin. Preferably, it also contains a photocurable resin, a thermosetting resin, a photopolymerization initiator, and an inorganic filler. Each component of the curable resin composition used to form the resin layer of the present invention is described in detail below.

[0023] (thermosetting resin) When a curable resin composition contains a thermosetting resin, the heat resistance of the cured product is improved, as is the adhesion to the substrate. As the thermosetting resin, known and conventional thermosetting resins such as isocyanate compounds, blocked isocyanate compounds, amino resins, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, epoxy compounds, polyfunctional oxetane compounds, and episulfide resins can be used. Among these, epoxy compounds, polyfunctional oxetane compounds, and compounds having two or more thioether groups in the molecule, i.e., episulfide resins, are preferred, and epoxy compounds are more preferred. The thermosetting resin can be used individually or in combination of two or more.

[0024] The epoxy compounds mentioned above are compounds having epoxy groups, and any conventionally known ones can be used. Examples include polyfunctional epoxy compounds having multiple epoxy groups in the molecule. Hydrogenated epoxy compounds may also be used.

[0025] Examples of polyfunctional epoxy compounds include epoxidized vegetable oils; bisphenol A type epoxy resins; hydroquinone type epoxy resins; bisphenol type epoxy resins; thioether type epoxy resins; brominated epoxy resins; novolac type epoxy resins; biphenol novolac type epoxy resins; bisphenol F type epoxy resins; hydrogenated bisphenol A type epoxy resins; glycidylamine type epoxy resins; hydantoin type epoxy resins; alicyclic epoxy resins; trihydroxyphenylmethane type epoxy resins; bixylenol type or biphenol type epoxy resins or mixtures thereof. Examples of epoxy resins include, but are not limited to, bisphenol S type epoxy resins, bisphenol A novolac type epoxy resins, tetraphenyloleethane type epoxy resins, heterocyclic epoxy resins, diglycidyl phthalate resins, tetraglycidyl xylenoylethane resins, naphthalene group-containing epoxy resins, epoxy resins having a dicyclopentadiene skeleton, glycidyl methacrylate copolymer epoxy resins, copolymer epoxy resins of cyclohexylmaleimide and glycidyl methacrylate, epoxy-modified polybutadiene rubber derivatives, and CTBN-modified epoxy resins. These epoxy resins can be used individually or in combination of two or more. Among these, novolac type epoxy resins, bisphenol type epoxy resins, bixylenol type epoxy resins, biphenol type epoxy resins, biphenol novolac type epoxy resins, naphthalene type epoxy resins, or mixtures thereof are particularly preferred.

[0026] Examples of polyfunctional oxetane compounds include bis[(3-methyl-3-oxetanylmethoxy)methyl] ether, bis[(3-ethyl-3-oxetanylmethoxy)methyl] ether, 1,4-bis[(3-methyl-3-oxetanylmethoxy)methyl]benzene, 1,4-bis[(3-ethyl-3-oxetanylmethoxy)methyl]benzene, (3-methyl-3-oxetanyl)methyl acrylate, and (3-ethyl-3-oxetanyl)methyl acrylate. Examples include polyfunctional oxetanes such as relates, (3-methyl-3-oxetanyl)methyl methacrylate, (3-ethyl-3-oxetanyl)methyl methacrylate, and their oligomers or copolymers, as well as ethers of oxetane alcohols with resins having hydroxyl groups such as novolac resins, poly(p-hydroxystyrene), cardo-type bisphenols, calixarenes, calixresorcinarenes, or silsesquioxane. Other examples include copolymers of unsaturated monomers having an oxetane ring with alkyl (meth)acrylates.

[0027] Examples of compounds having multiple cyclic thioether groups in their molecules include bisphenol A-type episulfide resins. Furthermore, episulfide resins obtained by replacing the oxygen atoms in the epoxy groups of novolac-type epoxy resins with sulfur atoms using a similar synthesis method can also be used.

[0028] The amount of thermosetting resin included is, for example, 10 to 60% by mass of the total solid content of the curable resin composition.

[0029] (light curing resin) As the photocurable resin, any resin that hardens upon irradiation with active energy rays is acceptable, and compounds having one or more ethylenically unsaturated groups in their molecules are preferably used. As compounds having ethylenically unsaturated groups, known and conventional photosensitive monomers such as photopolymerizable oligomers and photopolymerizable vinyl monomers can be used, and radical polymerizable monomers and cationic polymerizable monomers may also be used. Furthermore, polymers such as carboxyl group-containing resins having ethylenically unsaturated groups, as described later, can be used as the photocurable resin. The photocurable resin can be used alone or in combination of two or more types.

[0030] As photosensitive monomers, photosensitive (meth)acrylate compounds that are liquid, solid, or semi-solid at room temperature and have one or more (meth)acryloyl groups in their molecule can be used. Photosensitive (meth)acrylate compounds that are liquid at room temperature serve to increase the photoreactivity of the composition, as well as to adjust the viscosity of the composition to suit various coating methods and to improve its solubility in alkaline aqueous solutions.

[0031] Examples of photopolymerizable oligomers include unsaturated polyester oligomers and (meth)acrylate oligomers. Examples of (meth)acrylate oligomers include epoxy (meth)acrylates such as phenol novolac epoxy (meth)acrylate, cresol novolac epoxy (meth)acrylate, and bisphenol-type epoxy (meth)acrylate, as well as urethane (meth)acrylate, epoxy urethane (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate, and polybutadiene-modified (meth)acrylate.

[0032] Photopolymerizable vinyl monomers include well-known and commonly used ones, such as styrene derivatives like styrene, chlorostyrene, and α-methylstyrene; vinyl esters such as vinyl acetate, vinyl butyrate, or vinyl benzoate; vinyl ethers such as vinyl isobutyl ether, vinyl-n-butyl ether, vinyl-t-butyl ether, vinyl-n-amyl ether, vinyl isoamyl ether, vinyl-n-octadecyl ether, vinylcyclohexyl ether, ethylene glycol monobutyl vinyl ether, and triethylene glycol monomethyl vinyl ether; and acrylic compounds. (Meth)acrylamides such as lylamide, methacrylamide, N-hydroxymethylacrylamide, N-hydroxymethylmethacrylamide, N-methoxymethylacrylamide, N-ethoxymethylacrylamide, N-butoxymethylacrylamide; allyl compounds such as triallyl isocyanurate, diallyl phthalate, diallyl isophthalate; 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobolonyl (meth)acrylate, phenyl (meth)acrylate, f Esters of (meth)acrylic acid such as phenoxyethyl (meth)acrylate; hydroxyalkyl (meth)acrylates such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and pentaerythritol tri(meth)acrylate; alkoxyalkylene glycol mono(meth)acrylates such as methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate; ethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1 Alkylene polyol poly(meth)acrylates such as 6-hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate; polyoxyalkylene glycol poly(meth)acrylates such as diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, ethoxylated trimethylolpropane triacrylate, and propoxylated trimethylolpropane tri(meth)acrylate;Examples include poly(meth)acrylates such as neopentyl glycol hydroxyvivariate ester di(meth)acrylate; and isocyanurate-type poly(meth)acrylates such as tris[(meth)acryloxyethyl]isocyanurate.

[0033] The amount of photocurable resin included is, for example, 10 to 60% by mass of the total solid content of the curable resin composition.

[0034] (Alkali-soluble resin) Examples of alkali-soluble resins include compounds having two or more phenolic hydroxyl groups, carboxyl group-containing resins, compounds having both phenolic hydroxyl groups and carboxyl groups, and compounds having two or more thiol groups. Among these, alkali-soluble resins that contain carboxyl groups are preferred because they improve adhesion to the substrate and have excellent developability. The carboxyl group-containing resin may be a carboxyl group-containing photosensitive resin having an ethylenically unsaturated group, or a carboxyl group-containing resin that does not have an ethylenically unsaturated group. Alkali-soluble resins can be used individually or in combination of two or more types.

[0035] Specific examples of carboxyl group-containing resins include the following compounds (which may be either oligomers or polymers):

[0036] (1) A carboxyl group-containing 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.

[0037] (2) A carboxyl group-containing urethane resin obtained by polyaddition reaction of diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates with carboxyl group-containing dialcohol compounds such as dimethylolpropionic acid and dimethylolbutanoic acid, and diol compounds such as polycarbonate polyols, polyether polyols, polyester polyols, polyolefin polyols, acrylic polyols, bisphenol A alkylene oxide adduct diols, and compounds having phenolic hydroxyl groups and alcoholic hydroxyl groups.

[0038] (3) A urethane resin containing terminal carboxyl groups, obtained by reacting an acid anhydride at the ends of a urethane resin by polyaddition reaction of a diisocyanate compound such as aliphatic diisocyanate, branched aliphatic diisocyanate, alicyclic diisocyanate, or aromatic diisocyanate with a diol compound such as a polycarbonate polyol, polyether polyol, polyester polyol, polyolefin polyol, acrylic polyol, bisphenol A alkylene oxide adduct diol, or a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

[0039] (4) Diisocyanates and carboxyl group-containing urethane resins obtained by polyaddition reactions of (meth)acrylates or partially acid anhydride-modified products thereof of bifunctional epoxy resins such as bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bixylenol type epoxy resin, and biphenol type epoxy resin, carboxyl group-containing dialcohol compounds, and diol compounds.

[0040] (5) A carboxyl group-containing urethane resin obtained by adding a compound having one hydroxyl group and one or more (meth)acryloyl groups in the molecule, such as hydroxyalkyl (meth)acrylate, during the synthesis of the resin described in (2) or (4) above, and then (meth)acrylizing the terminal (meth)acrylic.

[0041] (6) A carboxyl group-containing urethane resin obtained by adding a compound having one isocyanate group and one or more (meth)acryloyl groups in its molecule, such as an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate, to the synthesis of the resin described in (2) or (4) above, and then (meth)acrylicating the terminal (meth)acrylic.

[0042] (7) A carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin with (meth)acrylic acid and adding dibasic acid anhydrides such as phthalic anhydride, tetrahydrophthalic anhydride, and hexahydrophthalic anhydride to the hydroxyl groups present in the side chains.

[0043] (8) A carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin, in which the hydroxyl groups of a bifunctional epoxy resin are further epoxidized with epichlorohydrin, with (meth)acrylic acid, and then adding a dibasic acid anhydride to the resulting hydroxyl groups.

[0044] (9) A carboxyl group-containing polyester resin obtained by reacting a polyfunctional oxetane resin with a dicarboxylic acid and adding a dibasic acid anhydride to the resulting primary hydroxyl group.

[0045] (10) A carboxyl group-containing resin obtained by reacting a reaction product obtained by reacting a compound having multiple phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide with an unsaturated group-containing monocarboxylic acid, and then reacting the resulting reaction product with a polybasic acid anhydride.

[0046] (11) A carboxyl group-containing resin obtained by reacting a reaction product obtained by reacting a compound having multiple phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate with an unsaturated group-containing monocarboxylic acid, and then reacting the resulting reaction product with a polybasic acid anhydride.

[0047] (12) A carboxyl group-containing resin obtained by reacting an epoxy compound having multiple epoxy groups in one molecule with a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, such as p-hydroxyphenethyl alcohol, and an unsaturated group-containing monocarboxylic acid such as (meth)acrylic acid, and then reacting the alcoholic hydroxyl group of the reaction product with a polybasic acid anhydride such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, or adipic anhydride.

[0048] (13) A carboxyl group-containing resin obtained by further adding a compound having one epoxy group and one or more (meth)acryloyl groups in the molecule, such as glycidyl (meth)acrylate or α-methylglycidyl (meth)acrylate, to the carboxyl group-containing resin described in (1) to (12) above.

[0049] Alternatively, an alkali-soluble resin having at least one of an amide-imide structure and an imide structure may be used.

[0050] The acid value of the alkali-soluble resin is preferably in the range of 40 to 200 mg KOH / g, and more preferably in the range of 45 to 120 mg KOH / g. An acid value of 40 mg KOH / g or higher of the alkali-soluble resin facilitates alkali development, while an acid value of 200 mg KOH / g or lower facilitates the drawing of a normal cured product pattern, which is preferable.

[0051] The weight-average molecular weight of alkali-soluble resins varies depending on the resin skeleton, but a range of 1,500 to 150,000, and more preferably 1,500 to 100,000, is preferred. When the weight-average molecular weight is 1,500 or higher, tack-free performance is good, the moisture resistance of the coating film after exposure is good, film thinning during development is suppressed, and the decrease in resolution can be suppressed. On the other hand, when the weight-average molecular weight is 150,000 or lower, developability is good and storage stability is also excellent.

[0052] The amount of alkali-soluble resin added is, for example, 5 to 50% by mass of the total solid content of the curable resin composition.

[0053] (Photopolymerization initiator) The curable resin composition may contain a photopolymerization initiator. The photopolymerization initiator should be one that generates radicals upon light irradiation, thereby curing the composition. Light irradiation refers to irradiation with ultraviolet light in the wavelength range of 350 to 450 nm.

[0054] Examples of photopolymerization initiators include bis-(2,6-dichlorobenzoyl)phenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis-(2,6-dimethoxybenzoyl)phenylphosphine oxide, and bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylphenylphosphine oxide. Bisacylphosphine oxides such as methylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylphosphine methyl ester, 2-methylbenzoyldiphenylphosphine oxide, pivalo Monoacylphosphine oxides such as isopropyl ylphenylphosphinate (2,4,6-trimethylbenzoyldiphenylphosphine oxide); 1-hydroxycyclohexylphenyl ketone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]phenyl}-2-methyl-propan-1-one, 2-hydroxy-2-methyl-1 Hydroxyacetophenones such as phenylpropan-1-one; benzoins such as benzoin, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, and benzoin n-butyl ether; benzoin alkyl ethers; benzophenones such as benzophenone, p-methylbenzophenone, Michlar's ketone, methylbenzophenone, 4,4'-dichlorobenzophenone, and 4,4'-bisdiethylaminobenzophenone;Acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl)-1-[4-(4-morpholinyl)phenyl]-1-bu Acetophenones such as tanone and N,N-dimethylaminoacetophenone; thioxanthones such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, and 2-amylanthraquinone Anthraquinones such as 2-aminoanthraquinone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzoic acid esters such as ethyl-4-dimethylaminobenzoate, 2-(dimethylamino)ethyl benzoate, and p-dimethylbenzoate ethyl ester; 1,2-octanedione, 1-[4-(phenylthio)-,2-(O-benzoyloxime)], etanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-,1-(O-acetylo Examples include oxime esters such as xime; titanosenes such as bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole-1-yl)phenyl)titanium and bis(cyclopentadienyl)-bis[2,6-difluoro-3-(2-(1-pyr-1-yl)ethyl)phenyl]titanium; phenyl disulfide 2-nitrofluorene, butyroin, anisoin ethyl ether, azobisisobutyronitrile, and tetramethylthiuram disulfide. The photopolymerization initiator may be used alone or in combination of two or more.

[0055] The amount of photopolymerization initiator added is, for example, 0.01 to 30% by mass of the total solid content of the curable resin composition.

[0056] (Curing accelerator) Curable resin compositions may contain curing accelerators. Examples of curing accelerators include imidazole derivatives such as imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; amine compounds such as dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N,N-dimethylbenzylamine, and 4-dimethylaminopyridine; hydrazine compounds such as adipic acid dihydrazide and sebacate dihydrazide; and phosphorus compounds such as triphenylphosphine. In addition, S-triazine derivatives such as guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino-S-triazine isocyanuric acid adduct, and 2,4-diamino-6-methacryloyloxyethyl-S-triazine isocyanuric acid adduct can also be used. Preferably, these compounds that also function as adhesion promoters are used in combination with the curing accelerator. The curing accelerator can be used alone or in combination of two or more types.

[0057] The amount of curing accelerator added is, for example, 0.01 to 30% by mass of the total solid content of the curable resin composition.

[0058] (thermoplastic resin) The curable resin composition may further contain a thermoplastic resin to improve the mechanical strength of the resulting cured film. The thermoplastic resin is preferably soluble in a solvent. When soluble in a solvent, flexibility is improved when the film is formed into a dry film, and crack formation and powder shedding can be suppressed. Examples of thermoplastic resins include thermoplastic polyhydroxypolyether resins, phenoxy resins which are condensates of epichlorohydrin and various difunctional phenolic compounds, or phenoxy resins obtained by esterifying the hydroxyl groups of the hydroxyether portion present in the skeleton using various acid anhydrides or acid chlorides, polyvinyl acetal resins, polyamide resins, polyamide-imide resins, block copolymers, and rubber particles. The thermoplastic resin can be used alone or in combination of two or more types.

[0059] The amount of thermoplastic resin blended is, for example, 0.01 to 10% by mass of the total solid content of the curable resin composition.

[0060] (Inorganic filler) The curable resin composition preferably contains an inorganic filler. By incorporating an inorganic filler, thermal properties such as adhesion, hardness, and crack resistance can be improved by matching the thermal strength with the conductive layer such as copper surrounding the insulating layer. Conventional known inorganic fillers can be used as the inorganic filler, and are not limited to any particular type, but examples include silica such as barium sulfate, barium titanate, amorphous silica, crystalline silica, fused silica, and spherical silica, as well as extender pigments such as talc, clay, Neuburg silica particles, boehmite, magnesium carbonate, calcium carbonate, titanium oxide, aluminum oxide, aluminum hydroxide, silicon nitride, aluminum nitride, and calcium zirconate, but barium sulfate and silica are preferred. Furthermore, the inorganic filler is preferably in the form of spherical particles. Among these, silica is preferred as it results in a low CTE and improves properties such as adhesion and hardness. The average particle size (median diameter, D50) of the inorganic filler is preferably 0.01 to 10 μm. As an inorganic filler, silica with an average particle diameter of 0.01 to 3 μm is preferred from the viewpoint of slit processability. In this specification, the average particle diameter of the inorganic filler includes not only the particle size of the primary particles but also the particle size of the secondary particles (aggregates). The average particle diameter can be determined by a laser diffraction particle size distribution analyzer. Examples of laser diffraction analyzers include the Nanotrac wave manufactured by Microtrac-Bell Corporation.

[0061] The inorganic filler may be surface-treated. Surface treatments may include surface treatment with a coupling agent or surface treatments that do not introduce organic groups, such as alumina treatment. The method of surface treatment of the inorganic filler is not particularly limited; any known and conventional method may be used. The surface of the inorganic filler may be treated with a surface treatment agent having a curable reactive group, such as a coupling agent having a curable reactive group as an organic group.

[0062] The inorganic filler may be blended in powder or solid form, or it may be blended after being mixed with a solvent or dispersant to form a slurry.

[0063] The inorganic filler may be used alone or as a mixture of two or more types. The amount of inorganic filler in the curable resin composition is preferably 10 to 90% by mass, more preferably 10 to 60% by mass, even more preferably 20 to 70% by mass, and most preferably 30 to 60% by mass, based on solid content. When the amount of inorganic filler is 10% by mass or more, thermal expansion is suppressed and heat resistance is improved, while when it is 90% by mass or less, resolution is improved.

[0064] (Coloring agent) The curable resin composition may contain a coloring agent. Known coloring agents such as red, blue, green, yellow, black, and white can be used, and may be pigments, dyes, or colorants. However, from the viewpoint of reducing environmental impact and affecting human health, it is preferable that the coloring agent does not contain halogens. The coloring agent can be used individually or in combination of two or more.

[0065] The amount of colorant added is, for example, 0.01 to 10% by mass of the total solid content of the curable resin composition.

[0066] (Organic solvents) The curable resin composition may contain an organic solvent for purposes such as preparing the composition or adjusting its viscosity when applying it to a substrate or the first film. As organic solvents, known and commonly used organic solvents can be used, such as ketones like methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons like toluene, xylene, and tetramethylbenzene; glycol ethers like cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, diethylene glycol monomethyl ether acetate, and tripropylene glycol monomethyl ether; esters like ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; aliphatic hydrocarbons like octane and decane; and petroleum-based solvents such as petroleum ether, petroleum naphtha, and solvent naphtha. These organic solvents can be used individually or in combination of two or more types.

[0067] (Other optional components) Furthermore, the curable resin composition may contain other additives known and commonly used in the field of electronic materials. Examples of other additives include polymerization inhibitors, ultraviolet absorbers, silane coupling agents, plasticizers, flame retardants, antistatic agents, anti-aging agents, antioxidants, antibacterial and antifungal agents, defoaming agents, leveling agents, thickeners, adhesion promoters, thixotropic agents, photobase generators, photoinitiation aids, sensitizers, organic fillers, elastomers, release agents, surface treatment agents, dispersants, dispersion aids, surface modifiers, stabilizers, and phosphors.

[0068] The curable resin composition is not particularly limited and may be, for example, a thermosetting resin composition, a photocurable resin composition, or a photocurable thermosetting resin composition. It may also be an alkali-developable type.

[0069] The laminate of the present invention has a resin layer obtained by coating and drying a curable resin composition on a first film. First, the curable resin composition is diluted with an organic solvent to adjust to an appropriate viscosity, and then coated onto the first film to a uniform thickness using a comma coater, blade coater, lip coater, rod coater, squeeze coater, reverse coater, transfer roll coater, gravure coater, spray coater, etc. After that, the coated composition can be dried at a temperature of 40 to 130°C for 1 to 30 minutes to form the resin layer. There are no particular restrictions on the coating film thickness, but it is preferable that the film thickness after drying is 5 μm to 100 μm.

[0070] [First film] The first film is a film that supports the resin layer of the laminate, and when the laminate is laminated onto a substrate such as a substrate by heating or other means to form an integral structure, it is at least adhered to the resin layer. As the first film, for example, films made of thermoplastic resins such as polyethylene terephthalate (hereinafter also referred to as PET), polyethylene naphthalate, and other polyester films, polyimide films, polyamide-imide films, polyethylene films, polytetrafluoroethylene films, polypropylene films, and polystyrene films can be used. Among these, polyester films can be suitably used from the viewpoint of heat resistance, mechanical strength, and handling. The thickness of the first film is not particularly limited and is generally selected appropriately in the range of 10 to 150 μm depending on the application, but it is preferably 20 μm to 100 μm, and within this range, the effect of improving the handling of the film can be obtained. The thickness of the first film is more preferably 20 μm to 50 μm, and even more preferably 20 μm to 40 μm. The surface of the first film on which the resin layer is provided may be treated with a release agent. Furthermore, sputtering or an ultra-thin copper foil may be formed on the surface of the first film on which the resin layer is provided.

[0071] Any commercially available first film can be used as the first film. For example, T100-25 (manufactured by Mitsubishi Chemical Corporation), T100-38 (manufactured by Mitsubishi Chemical Corporation), T100-50 (manufactured by Mitsubishi Chemical Corporation), and E5041 (manufactured by Toyobo Co., Ltd.) can be used. Of these, T100-25 (manufactured by Mitsubishi Chemical Corporation), T100-38 (manufactured by Mitsubishi Chemical Corporation), and E5041 (manufactured by Toyobo Co., Ltd.) are preferred from the viewpoint of roll operability.

[0072] [Second film] The second film is provided on the side of the resin layer opposite to the first film for the purpose of preventing dust and other debris from adhering to the surface of the resin layer of the laminate, and for preventing physical damage to the surface of the resin layer when the laminate is slit, as well as improving handling. In this invention, the second film refers to the film that is peeled off from the resin layer before lamination when the laminate is integrally molded by lamination by heating or the like so that the resin layer side of the laminate is in contact with a substrate such as a substrate. Examples of materials used for the second film include polyethylene, polypropylene, polyvinyl chloride and other polyolefins, polyester such as PET and PEN, polycarbonate, polyimide, and the like.

[0073] Any commercially available second film can be used as the second film. For example, biaxially oriented polypropylene films MA-411, MA-420, MAM-430, etc., manufactured by Oji F-Tex Co., Ltd. can be used.

[0074] When laminating the second film to the resin layer, it is preferable to laminate the second film to the resin layer using a roll or press at a temperature of 25 to 50°C. The bonding pressure during the lamination process should be 0.01 kgf / cm². 2 ~20 kgf / cm² 2 It is preferable.

[0075] Furthermore, it is preferable to use a biaxially oriented polypropylene film as the second film, from the viewpoint that it can reduce cooling shrinkage after lamination onto the resin layer.

[0076] The thickness of the second film is not particularly limited, but is generally selected appropriately depending on the application, within the range of 10 to 100 μm. It is preferable that the surface on which the resin layer of the second film is provided is treated to improve adhesion, such as embossing, corona treatment, or micro-tack treatment, or a release treatment.

[0077] A conventionally known method can be used to manufacture a printed circuit board using the laminate of the present invention. For example, a printed circuit board can be manufactured by the following method: A second film is peeled off from the laminate, and the laminated structure is bonded to a circuit board on which a circuit pattern has been formed, so that the resin layer is in contact with the substrate, and then heat-laminated. Subsequently, the laminate is selectively exposed with active energy rays through a photomask on which a predetermined pattern has been formed, and after peeling off the first film, the unexposed areas are developed with a dilute alkaline aqueous solution (for example, a 0.3-3% by mass sodium carbonate aqueous solution) to form a pattern with cured material. Furthermore, by irradiating the cured material with active energy rays and then heat-curing it (for example, 100-220°C), or irradiating it with active energy rays after heat curing, or performing final finishing curing (main curing) by heat curing alone, a cured film with excellent properties such as adhesion and hardness can be formed.

[0078] The laminate of the present invention can be preferably used to form permanent protective films for electronic components, particularly printed circuit boards, and is especially suitable for forming solder resist layers, interlayer insulating layers, and coverlays for flexible printed circuit boards. A circuit board may also be formed by bonding wiring using the laminate of the present invention. It can also be used as a encapsulant for semiconductor chips. [Examples]

[0079] The present invention will be described in detail below with reference to examples and comparative examples, but it should be noted that the present invention is not limited to the following examples. In the following, "parts" and "%" all refer to mass unless otherwise specified.

[0080] <Preparation of photocurable resin 1> First, 456 parts of bisphenol A, 228 parts of water, and 649 parts of 37% formalin were charged into a flask equipped with a condenser and a stirrer. The temperature was kept below 40°C, and 228 parts of 25% sodium hydroxide aqueous solution were added. After the addition was complete, the mixture was reacted at 50°C for 10 hours. After the reaction was complete, the mixture was cooled to 40°C, and while maintaining the temperature below 40°C, 37.5% phosphoric acid aqueous solution was added to neutralize the pH to 4, and the mixture was allowed to stand to separate the aqueous layer. After separating the aqueous layer, 300 parts of methyl isobutyl ketone was added and dissolved uniformly, then washed three times with 500 parts of distilled water, and the mixture was reduced under reduced pressure at a temperature below 50°C to remove water, solvent, etc., and obtain a polymethylol compound. The obtained polymethylol compound was dissolved in 550 parts of methanol to obtain 1230 parts of a methanol solution of the polymethylol compound. A portion of the methanol solution of the obtained polymethylol compound was dried in a vacuum dryer at room temperature, and the solid content was 55.2%. Next, 500 parts of a methanol solution of the obtained polymethylol compound and 440 parts of 2,6-xylenol were charged and uniformly dissolved at 50°C. After uniform dissolution, methanol was removed under reduced pressure at a temperature below 50°C. Then, 8 parts of oxalic acid were added and the mixture was reacted at 100°C for 10 hours. After the reaction was complete, the distillate was removed under reduced pressure at 180°C and 50 mmHg to obtain 550 parts of novolac resin A. Next, 130 parts of novolac resin A obtained in the above procedure, 2.6 parts of 50% sodium hydroxide aqueous solution, and 100 parts of toluene / methyl isobutyl ketone (mass ratio = 2 / 1) were charged into an autoclave equipped with a thermometer, a nitrogen introduction device / alkylene oxide introduction device, and a stirring device. The system was then purged with nitrogen while stirring, and the temperature was raised to 150°C and 8 kgf / cm². 2 Then, 45 parts of ethylene oxide were gradually introduced and the reaction was carried out. The gauge pressure was 0.0 kgf / cm². 2The reaction was continued for approximately 4 hours until the desired result was reached, after which it was cooled to room temperature. 3.3 parts of 36% hydrochloric acid aqueous solution were added to the resulting reaction solution and mixed to neutralize the sodium hydroxide. The resulting neutralization reaction product was diluted with toluene, washed three times with water, and desolvented using an evaporator to obtain an ethylene oxide adduct of novolac resin A with a hydroxyl value of 175 g / eq. The ethylene oxide adduct of novolac resin A had an average of 1 mole of ethylene oxide added per equivalent of phenolic hydroxyl groups. Next, 175 parts of the ethylene oxide adduct of the obtained novolac resin A, 50 parts of acrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.1 parts of hydroquinone monomethyl ether, and 130 parts of toluene were charged into a reactor equipped with a stirrer, thermometer, and air blowing tube. The mixture was stirred while blowing air into it, and the temperature was raised to 115°C to allow the reaction to proceed. The reaction was continued for a further 4 hours while the water produced by the reaction was removed by distillation as an azeotrope with toluene, and then cooled to room temperature. The resulting reaction solution was washed with water using a 5% NaCl aqueous solution, and toluene was removed by distillation under reduced pressure. Diethylene glycol monoethyl ether acetate was then added to obtain a photocurable resin 1 with a solid content of 68%.

[0081] <Preparation of curable resin composition> The components listed in the upper column of Table 1 were mixed in the amounts (solid content) shown in the table, pre-mixed with a stirrer, and then kneaded in a three-roll mill to prepare the curable resin compositions for each of Examples 1-5 and Comparative Examples 1-3.

[0082] <Creation of the first film-resin layer laminate> Each prepared curable resin composition was coated onto each of the first films (PET films) listed in Table 1 using a Hirano Techseed Co., Ltd. Standard Lab Coater, adjusting the amount of solvent so that the viscosity was 0.5 to 20 dPa·s (rotational viscometer 5 rpm, 25°C), so that the resin layer thickness after drying was 25 μm. The resin layer was then dried in a drying oven with a temperature gradient of 80°C to 100°C so that the residual solvent in the resin layer was 0.5 to 2.5% by mass, forming a resin layer on the first film and creating a laminate of the first film-resin layer.

[0083] <Measurement of the tensile modulus of the first film> In addition, the tensile modulus of each first film (PET film) was measured and calculated using an RSA-G2 instrument manufactured by TA Instruments, Inc., in accordance with the procedure described below, in accordance with JIS K 7161-1:2014, Method for Determining Tensile Properties of Plastics. Specifically, 3 mm wide test specimens were first cut from each of the first films in each TD direction (longitudinal direction of the film) and MD direction (width direction of the film). Each obtained test specimen was subjected to a tensile test at a temperature of 25°C, with a grip distance of 10 mm, constant velocity movement at a tensile speed of 0.002 mm / sec (0.12 mm / min), and load measurement conditions. The tensile modulus of elasticity in each of the TD direction (longitudinal direction of the film) and MD direction (width direction of the film) of the first film was determined from the slope of the regression line drawn at elongation rates of 0.05% to 0.25% in the elongation-stress curve obtained from the tensile test. Specifically, it was calculated based on the following formula 1. Then, the average value for each TD direction (longitudinal direction of the film) and MD direction (width direction of the film) was calculated and taken as the tensile modulus of elasticity of the first film. The results are shown in Table 1. TIFF2026109383000003.tif24165

[0084] <Measurement of the storage modulus of the resin layer> In the first film-resin layer laminate created, a vacuum laminator MVLP-500 (manufactured by Meiki Seisakusho, Japan Steel Works Ltd.) was used to repeatedly bond the resin layers together under the following conditions (temperature 40°C, time 120 sec, pressure 0.5 MPa) to prepare a sample for melt viscosity measurement with a thickness of 400 μm and a size of 50 × 50 mm. Subsequently, it was processed into a circular shape with a measurement size of φ20 mm, and the first film was peeled off to prepare a sample for measurement. The storage modulus of the resin layer was measured using a rheometer HAAKE MARS40 (manufactured by Thermo Fisher) under the conditions of a sensor parallel plate of φ20 mm, strain of 0.001~1%, oscillation mode at a frequency of 1 Hz, and temperature of 30°C. The measurement results are shown in Table 1.

[0085] <Evaluation of resin layer separation> On the surface of the resin layer of the first film-resin layer laminate prepared in the above-mentioned <Preparation of the first film-resin layer laminate>, a nip roll surface temperature of 25°C and a pressure of 0.1 kgf / cm² were applied. 2 The settings were adjusted, and a second film (MA-411, manufactured by Oji F-Tex Co., Ltd.) was laminated to produce 1000m of roll-shaped laminates for Examples 1-5 and Comparative Examples 1-3, each having a three-layer structure of the first film, resin layer, and second film. These were then slit into strips 495mm wide and 20m long using a general-purpose film slitter 536A (manufactured by Godo Kiko Co., Ltd.). The prepared long, three-layer laminate (59-90 μm thick, 495 mm wide, 20 m long roll product) was set in a temporary lamination machine OTL-510MT (manufactured by ONC Co., Ltd.), and while peeling off the second film with the winding roll, 20 temporary lamination tests were performed consecutively on a 500 x 500 mm, 0.8 mm thick copper-clad laminate board at a lamination speed of 1 m / min, roll temperature of 90°C, and roll pressure of 0.2 MPa. The evaluation criteria were as follows. The evaluation results are shown in Table 1. 〇: Not a single instance of a tearful separation occurred out of 20 photos. ×: One or more out of 20 photos were separated due to tears.

[0086] [Table 1]

[0087] (*1): Photocurable resin 1 prepared using the method described above (*2): DPHA (Dipentaerythritol Hexaacrylate) (*3): Bisphenol A type epoxy resin jER834 manufactured by Mitsubishi Chemical Corporation (*4): Bisphenol A type epoxy resin jER828 manufactured by Mitsubishi Chemical Corporation (*5): Barium sulfate B-30 manufactured by Sakai Chemical Industry Co., Ltd. (*6): Silica SO-C2 manufactured by Admatex Co., Ltd. (*7): TPO(2,4,6-trimethylbenzoyldiphenylphosphine oxide) (*8): Melamine (*9): Dicyandiamide (*10): PET film T100-38 (thickness 38μm) manufactured by Mitsubishi Chemical Corporation. (*11): PET film T100-50 (thickness 50μm) manufactured by Mitsubishi Chemical Corporation. (*12): PET film E5041 manufactured by Toyobo Co., Ltd. (thickness 25μm) (*13): PET film T100-19 (thickness 19μm) manufactured by Mitsubishi Chemical Corporation.

[0088] From the results shown in the table above, it can be seen that the present invention provides a laminate in which the problem of separation of the resin layer does not occur even when slitting is performed continuously. [Explanation of Symbols]

[0089] 11 Laminate 12 resin layer 13 The first film 21 Laminate 22 Resin layer 23 First film 24 The second film

Claims

1. A laminate comprising a first film and a resin layer, The tensile modulus of the first film is 1.0 GPa to 5.0 GPa. A laminate characterized in that the storage modulus of the resin layer is 0.05 MPa to 3.0 MPa.

2. The laminate according to claim 1, wherein the resin layer is obtained from a curable resin composition comprising a photocurable resin, a thermosetting resin, a photopolymerization initiator, and an inorganic filler.

3. The laminate according to claim 1, wherein the thickness of the first film is 20 μm to 100 μm.

4. The laminate according to claim 2, wherein the curable resin composition contains 20% to 70% by mass of the inorganic filler on a solid content basis.

5. The laminate according to claim 2, wherein the inorganic filler contains silica.

6. A cured product characterized by curing the resin layer of the laminate described in claim 1.

7. An electronic component characterized by having the cured product described in claim 6.

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