Resin materials and multilayer printed wiring boards

Abstract

To provide a resin material capable of suppressing warpage of a cured material and shortening a baking time.SOLUTION: A resin material according to the invention contains: a thermosetting compound that does not have an aromatic ring in a structural portion excluding a thermosetting functional group, has two or more CH3 terminals in the structural portion excluding the thermosetting functional group, and satisfies a following formula (X); and inorganic filler. A content of the inorganic filler in 100 wt.% of the resin material excluding a solvent therein is 30 wt.% or more. 0.1≤A / (B×C)≤0.6...formula (X), A: number of CH3 terminals of the structural portion excluding the thermosetting functional group of the thermosetting compound, B: number of the thermosetting functional groups of the thermosetting compound, and C: number of carbon atoms of the structural portion excluding the thermosetting functional group of the thermosetting compound.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a resin material containing a thermosetting compound, and also to a multilayer printed wiring board using the resin material. [Background technology]

[0002] Conventionally, various resin materials have been used to obtain electronic components such as semiconductor devices, laminates, and printed wiring boards. For example, in multilayer printed wiring boards, resin materials are used to form insulating layers for insulating between internal layers and to form insulating layers located on the surface. Wiring, which is generally metal, is laminated on the surface of the insulating layer. Furthermore, resin films, which are formed by filming the resin materials, are sometimes used to form the insulating layers. The resin materials and resin films are used as insulating materials for multilayer printed wiring boards, including build-up films.

[0003] Patent Document 1 listed below discloses a resin composition containing (A) a monofunctional epoxy resin having a biphenyl structure and (B) a curing agent.

[0004] Patent Document 2 below discloses a resin composition containing (A) an epoxy resin having an ester skeleton, (B) an active ester-type curing agent, and (C) an inorganic filler. In this resin composition, the content of (C) the inorganic filler is 50% by mass or more when the nonvolatile components in the resin composition are taken as 100% by mass, and the content of (A) the epoxy resin having an ester skeleton is 1 to 20 parts by mass when the content of (C) the inorganic filler is taken as 100 parts by mass. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-095749 [Patent Document 2] Japanese Patent Application Laid-Open No. 2014-177530 Summary of the Invention [Problem to be solved by the invention]

[0006] In the manufacturing process of printed wiring boards and the like, a resin material is cured to form an insulating layer (a cured product of the resin material). Furthermore, in the manufacturing process of printed wiring boards and the like, a baking process (heat treatment) is performed before mounting electronic components and the like to thoroughly remove moisture and solvents contained in the insulating layer. If this baking process is insufficient, swelling occurs between the insulating layer and the metal layer during the reflow process performed when mounting electronic components and the like. With conventional resin materials such as those described in Patent Documents 1 and 2, moisture and solvents are difficult to remove from the insulating layer, which can result in long baking times. For this reason, when manufacturing printed wiring boards and the like using conventional resin materials, productivity can be reduced.

[0007] Furthermore, conventional resin materials may cause warping in the cured product. In particular, conventional resin materials containing an epoxy compound having an aromatic ring, such as those described in Patent Document 1, are more likely to cause warping in the cured product. When warping occurs in the cured product, warping also occurs in the circuit board and metal layer, resulting in a decrease in yield.

[0008] In recent years, in order to achieve high-speed communication in response to an increase in the amount of information transmitted, printed wiring boards and the like have become multilayered, larger, and have finer wiring, which has made the cured product more susceptible to warping and required longer baking times.

[0009] An object of the present invention is to provide a resin material that can suppress warping of the cured product and shorten the baking time, and also to provide a multilayer printed wiring board using the resin material. [Means for solving the problem]

[0010] According to a broad aspect of the present invention, there is provided a resin material comprising: a thermosetting compound that has no aromatic ring in a structural portion excluding the thermosetting functional group, has two or more CH3 terminals in a structural portion excluding the thermosetting functional group, and satisfies the following formula (X); and an inorganic filler, wherein the content of the inorganic filler is 30 wt% or more based on 100 wt% of the components of the resin material excluding the solvent.

[0011] 0.1≦A / (B×C)≦0.6...Formula (X) A: The number of CH3 ends possessed by the structural portion of the thermosetting compound excluding the thermosetting functional group B: The number of thermosetting functional groups contained in the thermosetting compound C: the number of carbon atoms in the structural portion of the thermosetting compound excluding the thermosetting functional group

[0012] In a specific aspect of the resin material according to the present invention, the thermosetting compound has a tert-butyl group in a structural portion other than the thermosetting functional group, and the number of tert-butyl groups in the structural portion other than the thermosetting functional group of the thermosetting compound is one or more.

[0013] In a specific aspect of the resin material according to the present invention, the number of carbon atoms contained in the structural portion of the thermosetting compound excluding the thermosetting functional group is 5 or more and 30 or less.

[0014] In a specific aspect of the resin material according to the present invention, the thermosetting compound has one or two thermosetting functional groups.

[0015] In a specific aspect of the resin material according to the present invention, the thermosetting compound has one thermosetting functional group.

[0016] In a specific aspect of the resin material according to the present invention, a structural portion of the thermosetting compound other than the thermosetting functional group has a branched structure.

[0017] In a specific aspect of the resin material according to the present invention, the structural portion of the thermosetting compound excluding the thermosetting functional group has a branched structure, and the proportion of the number of carbon atoms in the chain having the largest number of atoms in the structural portion of the thermosetting compound excluding the thermosetting functional group, relative to the total number of carbon atoms in the structural portion of the thermosetting compound excluding the thermosetting functional group, is 40% or more and 90% or less.

[0018] In a specific aspect of the resin material according to the present invention, the resin material is a resin film.

[0019] The resin material according to the present invention is suitably used to form an insulating layer in a multilayer printed wiring board.

[0020] According to a broad aspect of the present invention, there is provided a multilayer printed wiring board comprising a circuit board, a plurality of insulating layers disposed on a surface of the circuit board, and a metal layer disposed between the plurality of insulating layers, wherein at least one of the plurality of insulating layers is a cured product of the resin material described above. [Effects of the Invention]

[0021] The resin material according to the present invention includes a thermosetting compound that does not have an aromatic ring in the structural portion excluding the thermosetting functional group, has two or more CH3 terminals in the structural portion excluding the thermosetting functional group, and satisfies the above formula (X), and an inorganic filler. The content of the inorganic filler is 30% by weight or more based on 100% by weight of the components excluding the solvent in the resin material. The resin material according to the present invention has the above-mentioned configuration, and therefore warping of the cured product can be suppressed and the baking time can be shortened. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a cross-sectional view schematically showing a multilayer printed wiring board using a resin material according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0023] The present invention will be described in detail below.

[0024] The resin material according to the present invention comprises a thermosetting compound that has no aromatic rings in the structural portion excluding the thermosetting functional group, has two or more CH3 terminals in the structural portion excluding the thermosetting functional group, and satisfies the following formula (X), and an inorganic filler. Hereinafter, "a thermosetting compound that has no aromatic rings in the structural portion excluding the thermosetting functional group, has two or more CH3 terminals in the structural portion excluding the thermosetting functional group, and satisfies the following formula (X)" may be referred to as a first thermosetting compound. The first thermosetting compound is a thermosetting component.

[0025] 0.1≦A / (B×C)≦0.6...Formula (X) A: the number of CH3 ends in the structural portion of the first thermosetting compound excluding the thermosetting functional group B: The number of thermosetting functional groups contained in the first thermosetting compound C: the number of carbon atoms in the structural portion of the first thermosetting compound excluding the thermosetting functional group

[0026] In the resin material according to the present invention, the content of the inorganic filler is 30% by weight or more based on 100% by weight of the components of the resin material excluding the solvent.

[0027] The resin material according to the present invention has the above-mentioned features, and therefore warping of the cured product can be suppressed and the baking time can be shortened.

[0028] Furthermore, since the resin material according to the present invention has the above-described structure, the dielectric loss tangent of the cured product can be reduced. Furthermore, the resin material according to the present invention has excellent reflow resistance.

[0029] With conventional resin materials, it is difficult to suppress warping of the cured product and shorten the baking time, especially with resin materials containing inorganic fillers or thermosetting compounds with aromatic rings.

[0030] In contrast, the resin material according to the present invention contains the specific first thermosetting compound, even though the resin material contains an inorganic filler, and therefore the baking time can be shortened. Furthermore, the resin material according to the present invention can satisfactorily form electronic components such as printed wiring boards, even with a shortened baking time.

[0031] Furthermore, the resin material according to the present invention may contain two or more types of thermosetting compounds. The resin material according to the present invention may contain a thermosetting compound different from the first thermosetting compound. Hereinafter, the "thermosetting compound different from the first thermosetting compound" may be referred to as the second thermosetting compound. The second thermosetting compound is a thermosetting component.

[0032] The resin material according to the present invention may be a resin composition or a resin film. The resin composition has fluidity. The resin composition may be in a paste form. The paste form includes a liquid form. The resin material according to the present invention is preferably a resin film because it is easy to handle.

[0033] The resin material according to the present invention is preferably a thermosetting material. When the resin material is a resin film, the resin film is preferably a thermosetting resin film.

[0034] Hereinafter, details of each component used in the resin material according to the present invention and uses of the resin material according to the present invention will be described.

[0035] [First thermosetting compound] The resin material according to the present invention includes the first thermosetting compound. The first thermosetting compound is a thermosetting compound that does not have an aromatic ring in the structural portion excluding the thermosetting functional group. The first thermosetting compound is a thermosetting compound that has two or more CH3 terminals in the structural portion excluding the thermosetting functional group. The first thermosetting compound is a thermosetting compound that satisfies the formula (X). Because the first thermosetting compound does not have an aromatic ring in the structural portion excluding the thermosetting functional group, the elastic modulus of the insulating layer can be improved and warping of the cured product can be effectively suppressed. Furthermore, because the first thermosetting compound satisfies the formula (X), the baking time can be effectively shortened and the dielectric loss tangent of the cured product can be reduced. The first thermosetting compound does not need to be a curing agent. Only one type of the first thermosetting compound may be used, or two or more types may be used in combination.

[0036] The first thermosetting compound does not have an aromatic ring in a structural portion other than the thermosetting functional group, and does not have, for example, a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a tetracene ring, a chrysene ring, a triphenylene ring, a tetraphene ring, a pyrene ring, a pentacene ring, a picene ring, or a perylene ring in a structural portion other than the thermosetting functional group.

[0037] The first thermosetting compound may have an aliphatic ring in a structural portion other than the thermosetting functional group, and the aliphatic ring may have a double bond in part of the ring.

[0038] Examples of the thermosetting functional group include an epoxy group, a maleimide group, a benzoxazine group, a cyanate group, a phenolic hydroxyl group, and an active ester group. The first thermosetting compound may be an epoxy compound, a maleimide compound, a benzoxazine compound, a cyanate compound, a phenol compound, or an active ester compound.

[0039] The epoxy group may be a glycidyl ester group, a glycidyl ether group, or an alicyclic epoxy group. When the epoxy group is a glycidyl ester group, the structural portion excluding the thermosetting functional group refers to the structural portion excluding the glycidyl ester group. When the epoxy group is a glycidyl ether group, the structural portion excluding the thermosetting functional group refers to the structural portion excluding the glycidyl ether group. When the epoxy group is an alicyclic epoxy group, the structural portion excluding the thermosetting functional group refers to the structural portion excluding the two carbon atoms and one oxygen atom forming the oxacyclopropane structure.

[0040] The thermosetting functional group of the first thermosetting compound is preferably an epoxy group or a maleimide group, and from the viewpoint of improving thermosetting properties, the first thermosetting compound is preferably an epoxy compound or a maleimide compound.

[0041] In order to exert the effects of the present invention, the first thermosetting compound is a thermosetting compound that satisfies the following formula (X).

[0042] 0.1≦A / (B×C)≦0.6...Formula (X) A: The number of CH3 ends in the structural portion of the first thermosetting compound excluding the thermosetting functional group B: Number of thermosetting functional groups in the first thermosetting compound C: the number of carbon atoms in the structural portion of the first thermosetting compound excluding the thermosetting functional group

[0043] In the formula (X), the value of "A / (B×C)" is 0.1 or more and 0.6 or less. In the formula (X), the value of "A / (B×C)" is preferably 0.2 or more and preferably 0.5 or less. When the value of "A / (B×C)" is equal to or more than the lower limit and equal to or less than the upper limit, the effects of the present invention can be more effectively exhibited.

[0044] The first thermosetting compound has two or more CH3 terminals in the structural portion excluding the thermosetting functional group, and therefore A in formula (X) is 2 or more. The number of CH3 terminals in the structural portion excluding the thermosetting functional group of the first thermosetting compound (A in formula (X)) is preferably 3 or more, more preferably 4 or more, and preferably 15 or less, more preferably 10 or less. When the number of CH3 terminals is equal to or greater than the above lower limit and equal to or less than the above upper limit, the effects of the present invention can be more effectively exhibited, and the solubility of the first thermosetting compound in the resin material can be increased.

[0045] Since the first thermosetting compound has a thermosetting functional group, B in the formula (X) is 1 or more. The number of thermosetting functional groups possessed by the first thermosetting compound (B in the formula (X)) may be 1, 2, 2 or more, or 3 or more. From the viewpoint of more effectively exerting the effects of the present invention, the number of thermosetting functional groups possessed by the first thermosetting compound is preferably 1 or 2, and more preferably 1. The first thermosetting compound is preferably a monofunctional or bifunctional thermosetting compound, and more preferably a monofunctional thermosetting compound.

[0046] The number of carbon atoms (C in the above formula (X)) contained in the structural portion excluding the thermosetting functional group of the first thermosetting compound is preferably 5 or more, more preferably 8 or more, and preferably 40 or less, more preferably 30 or less, and even more preferably 20 or less. When the number of carbon atoms is equal to or more than the above lower limit and equal to or less than the above upper limit, the effects of the present invention can be more effectively exerted. Furthermore, when the number of carbon atoms is equal to or less than the above upper limit, the solubility of the first thermosetting compound in the resin material can be increased.

[0047] The first thermosetting compound may or may not have atoms other than carbon in the structural portion other than the thermosetting functional group. The first thermosetting compound may or may not contain silicon atoms, and preferably does not contain silicon atoms.

[0048] From the viewpoint of effectively achieving the effects of the present invention, the first thermosetting compound preferably has a tert-butyl group in the structural portion excluding the thermosetting functional group. When the first thermosetting compound has a tert-butyl group in the structural portion excluding the thermosetting functional group, the number of CH3 ends (A in the above formula (X)) in the structural portion excluding the thermosetting functional group of the first thermosetting compound is 3 or more.

[0049] The tert-butyl group contained in the structural portion of the first thermosetting compound other than the thermosetting functional group The number of the tert-butyl groups is preferably at least 1. When the number of the tert-butyl groups is at least the above lower limit, the effects of the present invention can be more effectively exhibited.

[0050] From the viewpoint of effectively exerting the effects of the present invention and reducing the dielectric loss tangent of the cured product, it is preferable that the structural portion of the first thermosetting compound other than the thermosetting functional group has a branched structure.

[0051] The ratio of the number of carbon atoms in the chain having the largest number of atoms in the structural portion of the first thermosetting compound excluding the thermosetting functional group to the total number of carbon atoms in the structural portion of the first thermosetting compound excluding the thermosetting functional group is preferably 40% or more, more preferably 50% or more, and preferably 90% or less, more preferably 80% or less. When the ratio is equal to or greater than the lower limit and equal to or less than the upper limit, the effects of the present invention can be more effectively exhibited, and the dielectric loss tangent of the cured product can be further reduced.

[0052] From the viewpoint of effectively exerting the effects of the present invention, the molecular weight of the structural portion excluding the thermosetting functional group of the first thermosetting compound is preferably 100 or more, more preferably 110 or more, and preferably 400 or less, more preferably 300 or less.

[0053] The molecular weight of the structural portion of the first thermosetting compound excluding the thermosetting functional group means the molecular weight that can be calculated from the structural formula when the first thermosetting compound is not a polymer and when the structural formula of the first thermosetting compound can be identified.

[0054] In order to effectively exert the effects of the present invention, the molecular weight of the first thermosetting compound is preferably 150 or more, more preferably 200 or more, and preferably 600 or less, more preferably 500 or less.

[0055] The molecular weight of the first thermosetting compound means a molecular weight that can be calculated from the structural formula when the first thermosetting compound is not a polymer and when the structural formula of the first thermosetting compound can be identified. When the first thermosetting compound is a polymer, the molecular weight of the first thermosetting compound means a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

[0056] The content of the first thermosetting compound in 100% by weight of the components excluding the solvent in the resin material is preferably 0.5% by weight or more, more preferably 1% by weight or more, and even more preferably 2% by weight or more, and is preferably 30% by weight or less, and more preferably 25% by weight or less. When the content of the first thermosetting compound is equal to or more than the above lower limit and equal to or less than the above upper limit, the effects of the present invention can be more effectively exhibited, and the dielectric loss tangent of the cured product can be further reduced.

[0057] The content of the first thermosetting compound in 100% by weight of the components in the resin material excluding the inorganic filler and solvent is preferably 1% by weight or more, more preferably 3% by weight or more, even more preferably 5% by weight or more, and particularly preferably 10% by weight or more. The content of the first thermosetting compound in 100% by weight of the components in the resin material excluding the inorganic filler and solvent is preferably 80% by weight or less, more preferably 70% by weight or less, even more preferably 60% by weight or less, particularly preferably 60% by weight or less, and most preferably 50% by weight or less. When the content of the first thermosetting compound is equal to or greater than the above lower limit and equal to or less than the above upper limit, the effects of the present invention can be more effectively exhibited and the dielectric loss tangent of the cured product can be further reduced.

[0058] [Second thermosetting compound] The resin material preferably contains the second thermosetting compound. The second thermosetting compound may be a thermosetting compound having an aromatic ring in a structural portion excluding the thermosetting functional group. The second thermosetting compound may be a thermosetting compound having one CH3 terminal or no CH3 terminal in a structural portion excluding the thermosetting functional group. The second thermosetting compound may be a thermosetting compound that does not satisfy formula (X). The second thermosetting compound may be a thermosetting compound satisfying formula (Y1) below, or a thermosetting compound satisfying formula (Y2) below. The second thermosetting compound does not have to be a curing agent. The second thermosetting compound may be a curing agent. Only one type of second thermosetting compound may be used, or two or more types may be used in combination.

[0059] A' / (B'×C')<0.1 Formula (Y1) A' / (B'×C')>0.6 Equation (Y2)

[0060] In the above formula (Y1) and formula (Y2), A', B' and C' have the following meanings.

[0061] A': the number of CH3 ends in the structural portion of the second thermosetting compound excluding the thermosetting functional group B': the number of thermosetting functional groups in the second thermosetting compound C': the number of carbon atoms in the structural portion of the second thermosetting compound excluding the thermosetting functional group

[0062] Examples of the second thermosetting compound include epoxy compounds, maleimide compounds, phenol compounds, active ester compounds, cyanate ester compounds, benzoxazine compounds, carbodiimide compounds, acid anhydrides, amine compounds, thiol compounds, phosphine compounds, dicyandiamide, vinyl compounds, styrene compounds, phenoxy compounds, oxetane compounds, polyarylate compounds, diallyl phthalate compounds, acrylate compounds, episulfide compounds, (meth)acrylic compounds, amino compounds, unsaturated polyester compounds, polyurethane compounds, and silicone compounds.

[0063] The second thermosetting compound preferably contains at least one thermosetting compound selected from the group consisting of epoxy compounds, maleimide compounds, vinyl compounds, phenolic compounds, active ester compounds, cyanate ester compounds, benzoxazine compounds, carbodiimide compounds, and acid anhydrides. The second thermosetting compound more preferably contains at least one thermosetting compound selected from the group consisting of epoxy compounds, maleimide compounds, phenolic compounds, active ester compounds, cyanate ester compounds, benzoxazine compounds, and carbodiimide compounds. The second thermosetting compound more preferably contains at least an epoxy compound. In this case, the dielectric tangent of the cured product can be further reduced, and the thermal dimensional stability of the cured product can be further improved.

[0064] Among the second thermosetting compounds, "phenol compounds, active ester compounds, cyanate ester compounds, benzoxazine compounds, carbodiimide compounds, and acid anhydrides" are generally curing agents. Therefore, in this specification, "phenol compounds, active ester compounds, cyanate ester compounds, benzoxazine compounds, carbodiimide compounds, and acid anhydrides" may be referred to as "curing agents."

[0065] The second thermosetting compounds, namely, epoxy compounds, maleimide compounds, vinyl compounds, phenol compounds, active ester compounds, cyanate ester compounds, benzoxazine compounds, carbodiimide compounds, acid anhydrides, amine compounds, thiol compounds, phosphine compounds, and dicyandiamide, will be described in more detail below.

[0066] <Epoxy compounds> As the epoxy compound, a conventionally known epoxy compound can be used. The epoxy compound is an organic compound having at least one epoxy group. The epoxy compound may be used alone or in combination of two or more.

[0067] Examples of the epoxy compound include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, phenol novolac type epoxy compounds, biphenyl type epoxy compounds, biphenyl novolac type epoxy compounds, biphenol type epoxy compounds, naphthalene type epoxy compounds, fluorene type epoxy compounds, phenol aralkyl type epoxy compounds, naphthol aralkyl type epoxy compounds, dicyclopentadiene type epoxy compounds, anthracene type epoxy compounds, epoxy compounds having an adamantane skeleton, epoxy compounds having a tricyclodecane skeleton, naphthylene ether type epoxy compounds, and epoxy compounds having a triazine nucleus in the skeleton.

[0068] The epoxy compound may be a glycidyl ether compound, which is a compound having at least one glycidyl ether group.

[0069] From the viewpoint of further lowering the dielectric dissipation factor and improving the thermal dimensional stability and flame retardancy of the cured product, the epoxy compound preferably contains an epoxy compound having an aromatic skeleton, preferably contains an epoxy compound having a naphthalene skeleton or a phenyl skeleton, and more preferably is an epoxy compound having an aromatic skeleton.

[0070] From the viewpoint of further reducing the dielectric tangent and improving the coefficient of linear expansion (CTE) of the cured product, it is preferable that the epoxy compound contains an epoxy compound that is liquid at 25°C and an epoxy compound that is solid at 25°C.

[0071] The viscosity at 25°C of the epoxy compound that is liquid at 25°C is preferably 1000 mPa·s or less, and more preferably 500 mPa·s or less.

[0072] The viscosity of the epoxy compound can be measured using, for example, a dynamic viscoelasticity measuring device ("VAR-100" manufactured by Rheologica Instruments).

[0073] The molecular weight of the epoxy compound is more preferably 1000 or less. In this case, even if the content of the inorganic filler is 50% by weight or more based on 100% by weight of the components excluding the solvent in the resin material, a resin material with high fluidity can be obtained when forming an insulating layer. Therefore, when the uncured or B-staged resin material is laminated on a circuit board, the inorganic filler can be uniformly distributed.

[0074] The molecular weight of the epoxy compound means a molecular weight that can be calculated from the structural formula when the epoxy compound is not a polymer and when the structural formula of the epoxy compound can be identified, and when the epoxy compound is a polymer, means a weight average molecular weight.

[0075] From the viewpoint of further enhancing the thermal dimensional stability of the cured product, the content of the above-mentioned epoxy compound is preferably 4 wt% or more, more preferably 7 wt% or more, and preferably 15 wt% or less, more preferably 12 wt% or less, based on 100 wt% of the components in the resin material excluding the solvent.

[0076] The content of the epoxy compound in 100% by weight of the components in the resin material excluding the inorganic filler and the solvent is preferably 15% by weight or more, more preferably 25% by weight or more, and preferably 50% by weight or less, more preferably 40% by weight or less. When the content is equal to or greater than the above lower limit and equal to or less than the above upper limit, the thermal dimensional stability of the cured product can be further improved.

[0077] The weight ratio of the content of the epoxy compound to the total content of the first thermosetting compound and the curing agent (content of the epoxy compound / total content of the first thermosetting compound and the curing agent) is preferably 0.2 or more, more preferably 0.3 or more, and preferably 0.9 or less, more preferably 0.8 or less. When the weight ratio is equal to or greater than the lower limit and equal to or less than the upper limit, the dielectric tangent can be further reduced and the thermal dimensional stability can be further improved.

[0078] <Maleimide compounds> As the maleimide compound, a conventionally known maleimide compound can be used. The maleimide compounds may be used alone or in combination of two or more.

[0079] The maleimide compound may be a bismaleimide compound.

[0080] Examples of the maleimide compound include N-phenylmaleimide and N-alkylbismaleimide.

[0081] The maleimide compound preferably has a skeleton derived from a diamine compound other than dimer diamine or a triamine compound other than trimer triamine.

[0082] The maleimide compound may or may not have an aromatic ring, but preferably has an aromatic ring.

[0083] In the maleimide compound, it is preferable that the nitrogen atom in the maleimide skeleton is bonded to an aromatic ring.

[0084] From the viewpoint of further enhancing the thermal dimensional stability of the cured product, the content of the maleimide compound is preferably 0.5% by weight or more, more preferably 1% by weight or more, and preferably 15% by weight or less, more preferably 10% by weight or less, based on 100% by weight of the components excluding the solvent in the resin material.

[0085] The content of the maleimide compound in the resin material (100% by weight, excluding inorganic fillers and solvents) is preferably 2.5% by weight or more, more preferably 5% by weight or more, even more preferably 7.5% by weight or more, and preferably 50% by weight or less, more preferably 35% by weight or less. When the content of the maleimide compound is equal to or more than the above-mentioned lower limit and equal to or less than the above-mentioned upper limit, the thermal dimensional stability of the cured product can be further improved.

[0086] In order to effectively exert the effects of the present invention, the molecular weight of the maleimide compound is preferably 500 or more, more preferably 1,000 or more, and preferably less than 30,000, more preferably less than 20,000.

[0087] The molecular weight of the maleimide compound refers to a molecular weight that can be calculated from the structural formula when the maleimide compound is not a polymer and when the structural formula of the maleimide compound can be identified. When the maleimide compound is a polymer, the molecular weight refers to a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

[0088] Commercially available maleimide compounds include, for example, "BMI-4000" and "BMI-5100" manufactured by Daiwa Chemical Industry Co., Ltd., and "BMI-5100" manufactured by Designer Molecules Inc. Examples include the BMI-3000 manufactured by .

[0089] <Vinyl compounds> As the vinyl compound, a conventionally known vinyl compound can be used. The vinyl compound is an organic compound having at least one vinyl group. The vinyl compound may be used alone or in combination of two or more.

[0090] The vinyl compound includes a divinylbenzyl ether compound.

[0091] The content of the vinyl compound in 100% by weight of the components in the resin material excluding the inorganic filler and the solvent is preferably 5% by weight or more, more preferably 10% by weight or more, even more preferably 20% by weight or more, and preferably 80% by weight or less, more preferably 70% by weight or less. When the content of the vinyl compound is equal to or more than the above lower limit and equal to or less than the above upper limit, the thermal dimensional stability of the cured product can be further improved.

[0092] <Phenol compounds> Examples of the phenol compound include novolac type phenols, biphenol type phenols, naphthalene type phenols, dicyclopentadiene type phenols, aralkyl type phenols, and dicyclopentadiene type phenols.

[0093] Commercially available phenol compounds include novolac phenols (manufactured by DIC Corporation under the name "TD-2091"), biphenyl novolac phenols (manufactured by Meiwa Chemical Industry Co., Ltd. under the name "MEH-7851"), aralkyl phenol compounds (manufactured by Meiwa Chemical Industry Co., Ltd. under the name "MEH-7800"), and phenols having an aminotriazine skeleton (manufactured by DIC Corporation under the names "LA-1356" and "LA-3018-50P").

[0094] <Active ester compounds> The active ester compound refers to a compound that contains at least one ester bond in its structure and has an aliphatic chain, an aliphatic ring, or an aromatic ring bonded to both sides of the ester bond. The active ester compound can be obtained, for example, by a condensation reaction between a carboxylic acid compound or a thiocarboxylic acid compound and a hydroxy compound or a thiol compound. Examples of the active ester compound include compounds represented by the following formula (1):

[0095] [ka]

[0096] In the above formula (1), X1 represents a group containing an aliphatic chain, a group containing an aliphatic ring, or a group containing an aromatic ring, and X2 represents a group containing an aromatic ring. Preferred examples of the group containing an aromatic ring include an optionally substituted benzene ring and an optionally substituted naphthalene ring. Examples of the substituent include a hydrocarbon group. The number of carbon atoms in the hydrocarbon group is preferably 12 or less, more preferably 6 or less, and even more preferably 4 or less.

[0097] In the above formula (1), the combination of X1 and X2 includes a combination of an optionally substituted benzene ring and an optionally substituted benzene ring, and a combination of an optionally substituted benzene ring and an optionally substituted naphthalene ring. A combination of a naphthalene ring which may have a substituent and a naphthalene ring which may have a substituent is exemplified.

[0098] The active ester compound is not particularly limited. From the viewpoint of further improving thermal dimensional stability and flame retardancy, the active ester compound is preferably an active ester compound having two or more aromatic skeletons. From the viewpoint of lowering the dielectric tangent of the cured product and improving the thermal dimensional stability of the cured product, the active ester compound more preferably has a naphthalene ring in the main chain skeleton. From the viewpoint of further shortening the baking time, the active ester compound is preferably an active ester compound having three or more functional groups. From the viewpoint of more effectively suppressing warpage of the cured product, the resin material preferably contains an active ester compound having two or more functional groups and an active ester compound having three or more functional groups. The functional group is preferably an active ester group.

[0099] The equivalent weight of the active ester is preferably 200 or more, and preferably 450 or less, more preferably 400 or less, and even more preferably 350 or less. When the equivalent weight of the active ester is equal to or more than the above lower limit and equal to or less than the above upper limit, the baking time can be further shortened.

[0100] Commercially available products of the active ester compound include "HPC-8000-65T," "HPC-8000L-65MT," "EXB9416-70BK," "HPC-8150-62T," "HPC-8900-70BK," and "EXB8100-65T," manufactured by DIC Corporation.

[0101] <Cyanate ester compounds> Examples of the cyanate ester compounds include novolac cyanate ester resins, bisphenol cyanate ester resins, and prepolymers of these partially trimerized resins. Examples of the novolac cyanate ester resins include phenol novolac cyanate ester resins and alkylphenol cyanate ester resins. Examples of the bisphenol cyanate ester resins include bisphenol A cyanate ester resins, bisphenol E cyanate ester resins, and tetramethylbisphenol F cyanate ester resins.

[0102] Commercially available cyanate ester compounds include phenol novolac cyanate ester resins (PT-30 and PT-60 manufactured by Lonza Japan) and trimerized prepolymers of bisphenol cyanate ester resins (BA-230S, BA-3000S, BTP-1000S, and BTP-6020S manufactured by Lonza Japan).

[0103] The content of the cyanate ester compound in the resin material (100% by weight, excluding inorganic fillers and solvents) is preferably 10% by weight or more, more preferably 15% by weight or more, even more preferably 20% by weight or more, and preferably 85% by weight or less, more preferably 75% by weight or less. When the content of the cyanate ester compound is equal to or more than the lower limit and equal to or less than the upper limit, the thermal dimensional stability of the cured product can be further improved.

[0104] <Benzoxazine compounds> Examples of the benzoxazine compound include Pd-type benzoxazine and Fa-type benzoxazine.

[0105] Commercially available products of the above benzoxazine compounds include "Pd type" manufactured by Shikoku Chemicals Corporation.

[0106] The content of the benzoxazine compound in the resin material (100% by weight, excluding inorganic fillers and solvents) is preferably 1% by weight or more, more preferably 5% by weight or more, even more preferably 10% by weight or more, and preferably 70% by weight or less, more preferably 60% by weight or less. When the content of the benzoxazine compound is equal to or more than the lower limit and equal to or less than the upper limit, the thermal dimensional stability of the cured product can be further improved.

[0107] <Carbodiimide compounds> The carbodiimide compound is a compound having a structural unit represented by the following formula (2): In the following formula (2), the right end and the left end are bonding sites to other groups: The carbodiimide compound may be used alone or in combination of two or more types.

[0108] [ka]

[0109] In the above formula (2), X represents an alkylene group, a group in which a substituent is bonded to an alkylene group, a cycloalkylene group, a group in which a substituent is bonded to a cycloalkylene group, an arylene group, or a group in which a substituent is bonded to an arylene group, and p represents an integer of 1 to 5. When there are multiple Xs, the multiple Xs may be the same or different.

[0110] In one preferred embodiment, at least one X is an alkylene group, a group in which a substituent is bonded to an alkylene group, a cycloalkylene group, or a group in which a substituent is bonded to a cycloalkylene group.

[0111] Commercially available products of the carbodiimide compound include "Carbodilite V-02B," "Carbodilite V-03," "Carbodilite V-04K," "Carbodilite V-07," "Carbodilite V-09," "Carbodilite 10M-SP," and "Carbodilite 10M-SP (modified)," all manufactured by Nisshinbo Chemical Inc., as well as "Stavaxol P," "Stavaxol P400," and "Hykasil 510," all manufactured by Rhein Chemie.

[0112] <Acid anhydride> Examples of the acid anhydride include tetrahydrophthalic anhydride and alkylstyrene-maleic anhydride copolymer.

[0113] Commercially available products of the above acid anhydrides include "Rikacid TDA-100" manufactured by New Japan Chemical Co., Ltd.

[0114] The content of the curing agent relative to 100 parts by weight of the first thermosetting compound is preferably 70 parts by weight or more, more preferably 85 parts by weight or more, and preferably 150 parts by weight or less, more preferably 120 parts by weight or less. When the content of the curing agent is equal to or more than the above lower limit and equal to or less than the above upper limit, the curability is more excellent, the thermal dimensional stability is further improved, and the volatilization of remaining unreacted components can be further suppressed.

[0115] The content of the curing agent relative to 100 parts by weight of the total of the first thermosetting compound and the thermosetting compound excluding the curing agent of the second thermosetting compound is preferably 70 parts by weight or more, more preferably 85 parts by weight or more, and preferably 150 parts by weight or less, more preferably 120 parts by weight or less. When the content of the curing agent is equal to or greater than the above lower limit and equal to or less than the above upper limit, the curing property is more excellent, the thermal dimensional stability is more improved, and the volatilization of the remaining unreacted components can be more suppressed.

[0116] The total content of the first thermosetting compound and the curing agent in the resin material is preferably 50% by weight or more, more preferably 60% by weight or more, and preferably 95% by weight or less, based on 100% by weight of all components excluding the inorganic filler and the solvent. When the total content of the first thermosetting compound and the curing agent is equal to or more than the lower limit and equal to or less than the upper limit, the curability is further improved, and the thermal dimensional stability can be further enhanced.

[0117] The total content of the first thermosetting compound and the second thermosetting compound is preferably 50% by weight or more, more preferably 60% by weight or more, and preferably 95% by weight or less, based on 100% by weight of the components in the resin material excluding the inorganic filler and the solvent. When the total content of the first thermosetting compound and the second thermosetting compound is equal to or more than the lower limit and equal to or less than the upper limit, the curability is further improved and the thermal dimensional stability can be further enhanced.

[0118] [Inorganic filler] The resin material contains an inorganic filler. The use of the inorganic filler can further reduce the dielectric loss tangent of the cured product. Furthermore, the use of the inorganic filler can further reduce the dimensional change of the cured product due to heat. The inorganic filler may be used alone or in combination of two or more types.

[0119] Examples of the inorganic filler include silica, talc, clay, mica, hydrotalcite, alumina, magnesium oxide, aluminum hydroxide, aluminum nitride, and boron nitride.

[0120] From the viewpoints of reducing the surface roughness of the cured product, further increasing the adhesive strength between the cured product and the metal layer, forming finer wiring on the surface of the cured product, and imparting better insulation reliability to the cured product, the inorganic filler is preferably silica or alumina, more preferably silica, and even more preferably fused silica. The use of silica further reduces the thermal expansion coefficient of the cured product and further reduces the dielectric loss tangent of the cured product. Furthermore, the use of silica effectively reduces the surface roughness of the cured product and effectively increases the adhesive strength between the cured product and the metal layer. The silica is preferably spherical in shape.

[0121] From the viewpoint of promoting resin curing regardless of the curing environment, effectively increasing the glass transition temperature of the cured product, and effectively reducing the coefficient of linear thermal expansion of the cured product, it is preferable that the inorganic filler be spherical silica.

[0122] The inorganic filler has an average particle size of preferably 50 nm or more, more preferably 100 nm or more, even more preferably 500 nm or more, and preferably 5 μm or less, more preferably 3 μm or less, and even more preferably 1 μm or less. When the average particle size of the inorganic filler is equal to or greater than the above lower limit and equal to or less than the above upper limit, the surface roughness after etching can be reduced, the plating peel strength can be increased, and the adhesion between the insulating layer and the metal layer can be further improved.

[0123] The median diameter (d50) at 50% is used as the average particle diameter of the inorganic filler. The average particle diameter can be measured using a particle size distribution measuring device of the laser diffraction scattering type.

[0124] The inorganic filler is preferably spherical, and more preferably spherical silica. In this case, the surface roughness of the cured product is effectively reduced, and the cured product and the metal layer are easily bonded. When the inorganic filler is spherical, the aspect ratio of the inorganic filler is preferably 2 or less, and more preferably 1.5 or less.

[0125] The inorganic filler is preferably surface-treated, more preferably surface-treated with a coupling agent, and even more preferably surface-treated with a silane coupling agent. By surface-treating the inorganic filler, the surface roughness of the roughened cured product is further reduced, and the adhesive strength between the cured product and the metal layer is further increased. Furthermore, by surface-treating the inorganic filler, it is possible to form finer wiring on the surface of the cured product, and to impart better inter-wiring insulation reliability and interlayer insulation reliability to the cured product.

[0126] Examples of the coupling agent include a silane coupling agent, a titanium coupling agent, and an aluminum coupling agent, etc. Examples of the silane coupling agent include methacrylsilane, acrylsilane, aminosilane, imidazolesilane, vinylsilane, and epoxysilane.

[0127] In the present invention, the content of the inorganic filler is 30% by weight or more based on 100% by weight of the components excluding the solvent in the resin material. Even if the content of the inorganic filler is 30% by weight or more, the present invention can still be effective.

[0128] The content of the inorganic filler, based on 100% by weight of the components in the resin material excluding the solvent, is preferably 40% by weight or more, more preferably 50% by weight or more, preferably 90% by weight or less, more preferably 85% by weight or less, and even more preferably 80% by weight or less. When the content of the inorganic filler is above the lower limit, the dielectric loss tangent is effectively reduced. When the content of the inorganic filler is below the upper limit, the thermal dimensional stability is improved and warping of the cured product can be effectively suppressed. When the content of the inorganic filler is above the lower limit and below the upper limit, the surface roughness of the cured product can be further reduced and finer wiring can be formed on the surface of the cured product. Furthermore, this content of inorganic filler can reduce the thermal expansion coefficient of the cured product while also improving smear removability.

[0129] [Curing accelerator] The resin material preferably contains a curing accelerator. Use of the curing accelerator further accelerates the curing rate. Rapid curing of the resin material results in a uniform crosslinked structure in the cured product, a reduced number of unreacted functional groups, and a higher crosslink density. The curing accelerator is not particularly limited, and conventionally known curing accelerators can be used. Only one type of the curing accelerator may be used, or two or more types may be used in combination.

[0130] Examples of the curing accelerator include anionic curing accelerators such as imidazole compounds, cationic curing accelerators such as amine compounds, curing accelerators other than anionic and cationic curing accelerators such as phosphorus compounds and organometallic compounds, and radical curing accelerators such as peroxides.

[0131] Examples of the imidazole compound include 2-undecylimidazole, 2-heptadecylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4- Examples thereof include diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-dihydroxymethylimidazole.

[0132] Examples of the amine compound include diethylamine, triethylamine, diethylenetetramine, triethylenetetramine, and 4,4-dimethylaminopyridine.

[0133] Examples of the phosphorus compound include triphenylphosphine compounds.

[0134] Examples of the organometallic compound include zinc naphthenate, cobalt naphthenate, tin octoate, cobalt octoate, bisacetylacetonate cobalt(II), and trisacetylacetonate cobalt(III).

[0135] The peroxides include dicumyl peroxide and Perhexyl 25B.

[0136] From the viewpoint of further reducing the curing temperature and effectively suppressing warping of the cured product, the curing accelerator preferably contains the anionic curing accelerator, and more preferably contains the imidazole compound.

[0137] From the viewpoint of further lowering the curing temperature and effectively suppressing warpage of the cured product, the content of the anionic curing accelerator in 100% by weight of the curing accelerator is preferably 20% by weight or more, more preferably 50% by weight or more, even more preferably 70% by weight or more, and most preferably 100% by weight (total amount). Therefore, it is most preferable that the curing accelerator is the anionic curing accelerator.

[0138] The content of the curing accelerator is not particularly limited. The content of the curing accelerator is preferably 0.01% by weight or more, more preferably 0.05% by weight or more, and preferably 5% by weight or less, more preferably 3% by weight or less, based on 100% by weight of the components in the resin material excluding the inorganic filler and the solvent. When the content of the curing accelerator is equal to or greater than the lower limit and equal to or less than the upper limit, the resin material is cured efficiently. When the content of the curing accelerator is within a more preferred range, the storage stability of the resin material is further improved, and a better cured product is obtained.

[0139] [Thermoplastic resin] The resin material preferably contains a thermoplastic resin. Examples of the thermoplastic resin include polyvinyl acetal resin, polyimide resin, and phenoxy resin. The thermoplastic resin may be used alone or in combination of two or more.

[0140] From the viewpoint of effectively lowering the dielectric loss tangent and effectively improving the adhesion of metal wiring regardless of the curing environment, the thermoplastic resin is preferably a phenoxy resin. The use of a phenoxy resin prevents the resin film from impairing the ability to fill holes or irregularities in the circuit board and prevents the inorganic filler from becoming non-uniform. Furthermore, the use of a phenoxy resin improves the dispersibility of the inorganic filler because the melt viscosity can be adjusted, and the resin composition or B-staged product is less likely to wet and spread to unintended areas during the curing process.

[0141] The phenoxy resin contained in the resin material is not particularly limited. Conventionally known phenoxy resins can be used as the phenoxy resin. Only one type of the phenoxy resin may be used, or two or more types may be used in combination.

[0142] Examples of the phenoxy resin include phenoxy resins having a skeleton such as a bisphenol A skeleton, a bisphenol F skeleton, a bisphenol S skeleton, a biphenyl skeleton, a novolac skeleton, a naphthalene skeleton, and an imide skeleton.

[0143] Commercially available phenoxy resins include, for example, "YP50," "YP55," and "YP70" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., and "1256B40," "4250," "4256H40," "4275," "YX6954BH30," and "YX8100BH30" manufactured by Mitsubishi Chemical Corporation.

[0144] From the viewpoint of improving handling properties, plating peel strength at low roughness, and adhesion between the insulating layer and the metal layer, the thermoplastic resin is preferably a polyimide resin (polyimide compound).

[0145] From the viewpoints of improving the solubility, further reducing the dielectric loss tangent, and further shortening the baking time, the polyimide compound is preferably a polyimide compound obtained by a method of reacting a tetracarboxylic dianhydride with a dimer diamine.

[0146] Examples of the tetracarboxylic dianhydride include pyromellitic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-biphenylsulfonetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3',4,4'-biphenylethertetracarboxylic dianhydride, 3,3',4,4'-dimethyldiphenylsilanetetracarboxylic dianhydride, 3,3',4,4'-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylsulfonyl ether ... sulfide dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylsulfone dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, 3,3',4,4'-perfluoroisopropylidenediphthalic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, bis(phthalic acid)phenylphosphine oxide dianhydride, p-phenylene-bis(triphenylphthalic acid) dianhydride, m-phenylene-bis(triphenylphthalic acid) dianhydride, bis(triphenylphthalic acid)-4,4'-diphenylether dianhydride, and bis(triphenylphthalic acid)-4,4'-diphenylmethane dianhydride.

[0147] Examples of the dimer diamine include VERSAMINE 551 (trade name, manufactured by BASF Japan Ltd., 3,4-bis(1-aminoheptyl)-6-hexyl-5-(1-octenyl)cyclohexene), VERSAMINE 552 (trade name, manufactured by Cognix Japan Ltd., hydrogenated VERSAMINE 551), PRIAMINE 1075, and PRIAMINE 1074 (trade names, all manufactured by Croda Japan Ltd.).

[0148] The polyimide compound may have an acid anhydride structure, a maleimide structure, or a citraconic acid imide structure at its terminal. In this case, the polyimide compound can be reacted with an epoxy resin. By reacting the polyimide compound with an epoxy resin, the thermal dimensional stability of the cured product can be improved.

[0149] From the viewpoint of obtaining a resin material with even better storage stability, the above thermoplastic resins and the above polyolefins are preferred. The weight average molecular weight of the imide resin and the phenoxy resin is preferably 3,000 or more, more preferably 5,000 or more, and even more preferably 10,000 or more, and is preferably 100,000 or less, and more preferably 50,000 or less.

[0150] The weight average molecular weights of the thermoplastic resin, the polyimide resin, and the phenoxy resin are polystyrene-equivalent weight average molecular weights measured by gel permeation chromatography (GPC).

[0151] The contents of the thermoplastic resin, polyimide resin, and phenoxy resin are not particularly limited. The content of the thermoplastic resin (when the thermoplastic resin is a polyimide resin or a phenoxy resin, the content of the polyimide resin or the phenoxy resin) is preferably 1% by weight or more, more preferably 2% by weight or more, and preferably 30% by weight or less, more preferably 20% by weight or less, based on 100% by weight of the components in the resin material excluding the inorganic filler and the solvent. When the content of the thermoplastic resin is above the lower limit and below the upper limit, the resin material has good embedding properties in holes or irregularities in a circuit board. When the content of the thermoplastic resin is above the lower limit, the formation of a resin film becomes easier, and a better insulating layer can be obtained. When the content of the thermoplastic resin is below the upper limit, the thermal expansion coefficient of the cured product becomes even lower. When the content of the thermoplastic resin is below the upper limit, the surface roughness of the cured product becomes even smaller, and the adhesive strength between the cured product and a metal layer becomes even higher.

[0152] [solvent] The resin material contains or does not contain a solvent. By using the solvent, the viscosity of the resin material can be controlled within a suitable range, and the coating property of the resin material can be improved. The solvent may also be used to obtain a slurry containing the inorganic filler. The solvent may be used alone or in combination of two or more.

[0153] Examples of the solvent include acetone, methanol, ethanol, butanol, 2-propanol, 2-methoxyethanol, 2-ethoxyethanol, 1-methoxy-2-propanol, 2-acetoxy-1-methoxypropane, toluene, xylene, methyl ethyl ketone, N,N-dimethylformamide, methyl isobutyl ketone, N-methyl-pyrrolidone, n-hexane, cyclohexane, cyclohexanone, and naphtha, which is a mixture.

[0154] It is preferable that most of the solvent is removed when the resin composition is formed into a film. Therefore, the boiling point of the solvent is preferably 200°C or less, more preferably 180°C or less. The content of the solvent in the resin composition is not particularly limited. The content of the solvent can be appropriately changed taking into account the coatability of the resin composition, etc.

[0155] When the resin material is a B-stage film, the content of the solvent in 100% by weight of the B-stage film is preferably 1% by weight or more, more preferably 2% by weight or more, preferably 10% by weight or less, more preferably 5% by weight or less.

[0156] [Other ingredients] For the purpose of improving impact resistance, heat resistance, resin compatibility, workability, etc., the resin material may contain a leveling agent, a flame retardant, a coupling agent, a colorant, an antioxidant, an ultraviolet degradation inhibitor, an antifoaming agent, a thickener, a thixotropy-imparting agent, etc.

[0157] Examples of the coupling agent include a silane coupling agent, a titanium coupling agent, and an aluminum coupling agent, etc. Examples of the silane coupling agent include vinyl silane, amino silane, imidazole silane, and epoxy silane.

[0158] (resin film) The resin composition described above can be molded into a film to obtain a resin film (B-staged product / B-stage film). The resin material is preferably a resin film. The resin film is preferably a B-stage film.

[0159] Examples of methods for forming a resin composition into a film to obtain a resin film include the following: an extrusion molding method in which a resin composition is melt-kneaded using an extruder, extruded, and then molded into a film using a T-die, circular die, or the like; a casting molding method in which a resin composition containing a solvent is cast into a film; and other conventionally known film molding methods. Extrusion molding and casting molding are preferred because they can be used to make thinner films. Films include sheets.

[0160] The resin composition is formed into a film and dried by heating at, for example, 50°C to 150°C for 1 minute to 10 minutes to an extent that curing by heat does not proceed too much, thereby obtaining a resin film that is a B-stage film.

[0161] The film-like resin composition obtained by the drying process described above is called a B-stage film. The B-stage film is in a semi-cured state. The semi-cured product is not completely cured, and curing can continue.

[0162] The resin film does not have to be a prepreg. When the resin film is not a prepreg, migration does not occur along the glass cloth or the like. Furthermore, when the resin film is laminated or precured, irregularities due to the glass cloth do not occur on the surface.

[0163] The resin film can be used in the form of a laminated film comprising a metal foil or a base film and a resin film laminated on the surface of the metal foil or the base film. The metal foil is preferably a copper foil.

[0164] Examples of the substrate film of the laminated film include polyester resin films such as polyethylene terephthalate film and polybutylene terephthalate film, olefin resin films such as polyethylene film and polypropylene film, and polyimide resin films. The surface of the substrate film may be subjected to a release treatment, if necessary.

[0165] From the viewpoint of controlling the degree of cure of the resin film more uniformly, the thickness of the resin film is preferably 5 μm or more and preferably 200 μm or less. When the resin film is used as an insulating layer of a circuit, the thickness of the insulating layer formed by the resin film is preferably equal to or greater than the thickness of the conductor layer (metal layer) that forms the circuit. The thickness of the insulating layer is preferably 5 μm or more and preferably 200 μm or less.

[0166] (Semiconductor devices, printed wiring boards, copper-clad laminates and multilayer printed wiring boards) The above resin material is suitably used to form a molding resin in which a semiconductor chip is embedded in a semiconductor device.

[0167] The resin material is preferably used as an insulating material, and is preferably used to form an insulating layer in a printed wiring board.

[0168] The printed wiring board can be obtained by, for example, heat-pressure molding the resin material. .

[0169] A lamination target member having a metal layer on one or both sides can be laminated onto the resin film. A laminated structure can be suitably obtained, comprising a lamination target member having a metal layer on its surface and a resin film laminated on the surface of the metal layer, wherein the resin film is made of the resin material described above. The method for laminating the resin film and the lamination target member having the metal layer on its surface is not particularly limited, and known methods can be used. For example, the resin film can be laminated onto a lamination target member having a metal layer on its surface using a device such as a parallel plate press or a roll laminator, while applying pressure with or without heating.

[0170] The material of the metal layer is preferably copper.

[0171] The lamination target member having the metal layer on its surface may be a metal foil such as a copper foil.

[0172] The resin material is preferably used to obtain a copper-clad laminate, an example of which is a copper-clad laminate including a copper foil and a resin film laminated on one surface of the copper foil.

[0173] The thickness of the copper foil of the copper-clad laminate is not particularly limited. The thickness of the copper foil is preferably within a range of 1 μm to 50 μm. In addition, in order to increase the adhesive strength between the cured resin material and the copper foil, the copper foil preferably has fine irregularities on its surface. The method for forming the irregularities is not particularly limited. Examples of the method for forming the irregularities include a formation method using a known chemical solution.

[0174] The above resin materials are preferably used to obtain multilayer substrates.

[0175] An example of the multilayer substrate is a multilayer substrate including a circuit board and an insulating layer laminated on the circuit board. The insulating layer of the multilayer substrate is formed from the resin material. Alternatively, the insulating layer of the multilayer substrate may be formed from the resin film of the laminate film using a laminate film. The insulating layer is preferably laminated on the surface of the circuit board on which the circuits are provided. A portion of the insulating layer is preferably embedded between the circuits.

[0176] In the multilayer substrate, the surface of the insulating layer opposite to the surface on which the circuit board is laminated is preferably roughened.

[0177] The roughening treatment method is not particularly limited and may be any conventionally known roughening treatment method. The surface of the insulating layer may be subjected to swelling treatment before the roughening treatment.

[0178] Preferably, the multilayer substrate further comprises a copper plating layer laminated on the roughened surface of the insulating layer.

[0179] Another example of the multilayer substrate is a multilayer substrate comprising a circuit board, an insulating layer laminated on the surface of the circuit board, and copper foil laminated on the surface of the insulating layer opposite to the surface on which the circuit board is laminated. Preferably, the insulating layer is formed by using a copper-clad laminate comprising copper foil and a resin film laminated on one surface of the copper foil and curing the resin film. Furthermore, the copper foil is preferably etched to form a copper circuit.

[0180] Another example of the multilayer substrate is a circuit board and a plurality of insulating layers laminated on the surface of the circuit board. and a protective layer. At least one of the insulating layers arranged on the circuit board is formed using the resin material. The multilayer substrate preferably further includes a circuit laminated on at least one surface of the insulating layer formed using the resin film.

[0181] Among multilayer substrates, multilayer printed wiring boards require a low dielectric loss tangent and high insulation reliability from the insulating layer. The resin material according to the present invention can reduce the dielectric loss tangent and effectively improve insulation reliability by exhibiting the effects of the present invention. Therefore, the resin material according to the present invention is suitable for use in forming an insulating layer in a multilayer printed wiring board.

[0182] The multilayer printed wiring board includes, for example, a circuit board, a plurality of insulating layers disposed on a surface of the circuit board, and a metal layer disposed between the plurality of insulating layers, at least one of which is a cured product of the resin material.

[0183] FIG. 1 is a cross-sectional view schematically showing a multilayer printed wiring board using a resin material according to one embodiment of the present invention.

[0184] In the multilayer printed wiring board 11 shown in FIG. 1, multiple insulating layers 13-16 are laminated on the upper surface 12a of a circuit board 12. The insulating layers 13-16 are cured layers. A metal layer 17 is formed on a partial region of the upper surface 12a of the circuit board 12. Of the multiple insulating layers 13-16, the insulating layers 13-15 other than the insulating layer 16 located on the outer surface opposite the circuit board 12 have the metal layer 17 formed on a partial region of the upper surface. The metal layer 17 is a circuit. The metal layer 17 is disposed between the circuit board 12 and the insulating layer 13, and between each of the laminated insulating layers 13-16. The lower metal layer 17 and the upper metal layer 17 are connected to each other by at least one of via hole connection and through hole connection (not shown).

[0185] In the multilayer printed wiring board 11, the insulating layers 13 to 16 are formed from a cured product of the resin material. In this embodiment, the surfaces of the insulating layers 13 to 16 are roughened, and thus fine holes (not shown) are formed in the surfaces of the insulating layers 13 to 16. The metal layer 17 extends into the fine holes. In the multilayer printed wiring board 11, the width dimension (L) of the metal layer 17 and the width dimension (S) of the portion where the metal layer 17 is not formed can be reduced. In addition, the multilayer printed wiring board 11 provides good insulation reliability between upper and lower metal layers that are not connected by via hole connections or through hole connections (not shown).

[0186] (Roughening treatment and swelling treatment) The resin material is preferably used to obtain a cured product that is to be subjected to a roughening treatment or a desmear treatment. The cured product also includes a pre-cured product that can be further cured.

[0187] In order to form fine irregularities on the surface of the cured product obtained by pre-curing the resin material, the cured product is preferably subjected to a roughening treatment. The cured product is preferably subjected to a swelling treatment before the roughening treatment. The cured product is preferably subjected to a swelling treatment after pre-curing and before the roughening treatment, and then cured after the roughening treatment. However, the cured product does not necessarily have to be subjected to a swelling treatment.

[0188] As a method of the swelling treatment, for example, a method of treating the cured product with an aqueous solution or an organic solvent dispersion of a compound mainly composed of ethylene glycol or the like is used. The swelling liquid used for the swelling treatment generally contains an alkali as a pH adjuster or the like. The swelling liquid preferably contains sodium hydroxide. Specifically, for example, the swelling treatment is carried out with a solution of 40 wt % ethylene glycol or the like. The swelling treatment is carried out by treating the cured product with an aqueous ethylene glycol solution or the like at a temperature of 30°C to 85°C for 1 to 30 minutes. The temperature for the swelling treatment is preferably within the range of 50°C to 85°C. If the temperature for the swelling treatment is too low, the swelling treatment will take a long time, and the adhesive strength between the cured product and the metal layer will tend to be reduced.

[0189] For the roughening treatment, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfate compound is used. These chemical oxidizing agents are used as an aqueous solution or an organic solvent dispersion after water or an organic solvent is added. The roughening solution used for the roughening treatment generally contains an alkali as a pH adjuster. The roughening solution preferably contains sodium hydroxide.

[0190] Examples of the manganese compound include potassium permanganate and sodium permanganate. Examples of the chromium compound include potassium dichromate and anhydrous potassium chromate. Examples of the persulfate compound include sodium persulfate, potassium persulfate, and ammonium persulfate.

[0191] The arithmetic mean roughness Ra of the surface of the cured product is preferably 10 nm or more, preferably less than 300 nm, more preferably less than 200 nm, and even more preferably less than 150 nm. In this case, the adhesive strength between the cured product and the metal layer is increased, and even finer wiring is formed on the surface of the insulating layer. Furthermore, conductor loss can be reduced, and signal loss can be kept low. The arithmetic mean roughness Ra is measured in accordance with JIS B0601:1994.

[0192] (desmear treatment) Through holes may be formed in the cured product obtained by pre-curing the resin material. In the multilayer substrate, a via or a through hole is formed as the through hole. For example, a via can be formed by irradiating a laser such as a CO2 laser. The diameter of the via is not particularly limited, but is about 60 μm to 80 μm. The formation of the through holes often results in the formation of a smear, which is a resin residue derived from the resin component contained in the cured product, at the bottom of the via.

[0193] In order to remove the smear, the surface of the cured product is preferably subjected to a desmear treatment. The desmear treatment may also serve as a roughening treatment.

[0194] In the desmear treatment, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfate compound is used, as in the roughening treatment. These chemical oxidizing agents are used as an aqueous solution or an organic solvent dispersion after water or an organic solvent is added. The desmear treatment solution used in the desmear treatment generally contains an alkali. The desmear treatment solution preferably contains sodium hydroxide.

[0195] By using the above resin material, the surface roughness of the surface of the desmeared cured product is sufficiently reduced.

[0196] The present invention will be specifically described below by way of examples and comparative examples, but the present invention is not limited to the following examples.

[0197] The following materials were prepared:

[0198] (First thermosetting compound) Thermosetting compound X1: We prepared "Fine Oxocol Isostearic Acid" manufactured by Nissan Chemical Co., Ltd., which is a higher fatty acid. .

[0199] A reaction flask was charged with 50 parts by weight of Fine Oxocol isostearic acid, 40 parts by weight of allyl bromide, 19 parts by weight of potassium carbonate, and 450 parts by weight of N-methyl-2-pyrrolidone, and the mixture was stirred at 70°C for 3 hours to react. The resulting reaction solution was filtered, and the filtrate was washed with toluene and water. The organic layer was extracted, and the solvent was then distilled off. The resulting residue was purified by silica gel chromatography. 50 parts by weight of the purified compound and 660 parts by weight of chloroform were added to a reaction flask. 80 parts by weight of 3-chloroperbenzoic acid (70% purity) were added to the resulting solution with stirring, and the mixture was stirred at room temperature for 6 days to react. 450 parts by weight of a 10% by weight aqueous solution of sodium thiosulfate was added to the resulting reaction solution, and the organic layer was washed with a 5% by weight aqueous solution of sodium bicarbonate and water, and the solvent was then distilled off. The resulting residue was purified by silica gel chromatography to obtain thermosetting compound X1, a glycidyl ester compound.

[0200] Thermosetting compound X2: A higher fatty acid, "Fine Oxocol Isostearic Acid N" manufactured by Nissan Chemical Industries, Ltd., was prepared. A glycidyl ester compound, thermosetting compound X2, was obtained in the same manner as in the synthesis of thermosetting compound X1, except that Fine Oxocol Isostearic Acid N was used instead of Fine Oxocol Isostearic Acid.

[0201] Thermosetting compound X3: A reaction flask was charged with 30 parts by weight of 3,5,5-trimerylhexyl alcohol, 45 parts by weight of allyl bromide, 20 parts by weight of sodium hydride, and 500 parts by weight of tetrahydrofuran, and the mixture was stirred at 70°C for 30 hours to react. The resulting reaction solution was washed with water, extracted, and the solvent was then distilled off. The resulting residue was purified by silica gel chromatography. 30 parts by weight of the purified compound and 400 parts by weight of chloroform were added to a reaction flask. 50 parts by weight of 3-chloroperbenzoic acid were added to the resulting solution with stirring, and the mixture was stirred at room temperature for 4 days to react. 300 parts by weight of a 10% by weight aqueous solution of sodium thiosulfate was added to the resulting reaction solution, and the organic layer was washed with a 5% by weight aqueous solution of sodium bicarbonate and water, after which the solvent was distilled off. The resulting residue was purified by silica gel chromatography to obtain the glycidyl ether compound, thermosetting compound X3.

[0202] Thermosetting compound X4: A higher fatty acid, "Fine Oxocol Isostearic Acid T" manufactured by Nissan Chemical Industries, Ltd., was prepared. A glycidyl ester compound, thermosetting compound X4, was obtained in the same manner as in the synthesis of thermosetting compound X1, except that Fine Oxocol Isostearic Acid T was used instead of Fine Oxocol Isostearic Acid.

[0203] Thermosetting compound X5: An epoxy compound (glycidyl ether compound) "FOLDI E201" manufactured by Nissan Chemical Industries, Ltd. was used as the thermosetting compound X5.

[0204] Thermosetting compound X6: An epoxy compound (2-ethylhexyl glycidyl ether) "EX-121" manufactured by Nagase ChemteX Corporation was used as the thermosetting compound X6.

[0205] Thermosetting compound X7: 20 parts by weight of maleimidoacetic acid and 200 parts by weight of toluene were added to a reaction vessel equipped with a dropping funnel, a stirrer, a thermometer, a nitrogen inlet tube, and a sodium hydroxide aqueous solution trap, and 50 parts by weight of thionyl chloride was added dropwise at room temperature while stirring. After the dropwise addition was completed, the reaction mixture was heated at 50°C for 5 hours while stirring. The reaction mixture was distilled under reduced pressure to obtain maleimidoacetic acid chloride. 30 parts by weight of maleimidoacetyl chloride, 42 parts by weight of Fine Oxocol 180 (Nissan Chemical Industries, Ltd.), 0.2 parts by weight of paramethoxyphenol, and 450 parts by weight of toluene were placed in a reaction vessel and stirred for 2 hours while heating to 100°C. 10 parts by weight of pyridine was added dropwise over 30 minutes, and the mixture was stirred for 2 hours. Toluene was removed from the reaction mixture by distillation under reduced pressure, and the residue was dissolved in an ethyl acetate / toluene mixed solvent, recrystallized, and the solvent was removed to obtain thermosetting compound X7, a maleimide compound.

[0206] (Second Thermosetting Compound) Thermosetting compound Y1: A thermosetting compound Y1, which is a glycidyl ether compound, was obtained in the same manner as in the synthesis of the thermosetting compound X3, except that 3,5,5-di-tert-butylbenzyl alcohol was used instead of 3,5,5-trimerylhexyl alcohol.

[0207] Thermosetting compound Y2: An epoxy compound, "YX8034" manufactured by Mitsubishi Chemical Corporation, was used as the thermosetting compound Y2.

[0208] Thermosetting compound Y3: An epoxy compound, "JER871" manufactured by Mitsubishi Chemical Corporation, was used as the thermosetting compound Y3.

[0209] Thermosetting compound Y4: A biphenyl-type epoxy compound, "NC-3000" manufactured by Nippon Kayaku Co., Ltd., was used as the thermosetting compound Y4.

[0210] Thermosetting compound Y5: An epoxy compound, OGSOL PG-100 manufactured by Osaka Gas Chemicals Co., Ltd., was used as the thermosetting compound Y5.

[0211] Thermosetting compound Y6: An active ester compound, "HPC-8900-70BK" (active ester compound-containing liquid, solid content 70% by weight) manufactured by DIC Corporation, was used as the thermosetting compound Y6-containing liquid.

[0212] Thermosetting compound Y7: A phenol compound-containing liquid "LA-1356" (phenol compound-containing liquid, solid content 60% by weight) manufactured by DIC Corporation was used as the thermosetting compound Y7-containing liquid.

[0213] Thermosetting compound Y8: An active ester compound, "HPC-8150-62T" (active ester compound-containing liquid, solid content 62% by weight) manufactured by DIC Corporation, was used as the thermosetting compound Y8-containing liquid.

[0214] Thermosetting compound Y9: Under a nitrogen stream, 14.4 g of 1-naphthol, 350 g of tetrahydrofuran (THF), and 12.1 g of triethylamine were added to a three-necked flask and stirred until homogenous. Next, 9.1 g of isophthaloyl chloride was slowly added dropwise while the three-necked flask was cooled in an ice bath. After the addition, the mixture was stirred at room temperature (23°C) for 1 hour to allow the reaction to proceed. After the reaction, ethyl acetate was added to the reaction solution, which was then washed with a 1 mol / L aqueous nitric acid solution and then with water. The washed organic layer was dried over anhydrous magnesium sulfate, and the solution was evaporated under reduced pressure to obtain thermosetting compound Y9, an active ester compound.

[0215] Thermosetting compound Y10: Using a vessel equipped with a stirrer, reflux condenser, and Dean-Stark water separator, 21.1 parts by weight of trimellitic anhydride chloride was dissolved in 200 parts by weight of N-methyl-2-pyrrolidone. To the resulting solution, 14.4 parts by weight of 2-naphthol and 10.1 parts by weight of triethylamine were added, and the mixture was stirred at 25°C for 4 hours to react. To the resulting reaction solution, 8.9 parts by weight of a mixture of 2-methyl-4,6-diethyl-1,3-phenylenediamine and 2,4-diethyl-6-methyl-1,3-phenylenediamine was added, and the mixture was stirred at 25°C for 4 hours to react. 200 parts by weight of toluene was added to the resulting solution, and the mixture was refluxed at 150°C for 4 hours until no more water was generated. After the reaction was complete, the toluene was removed from the resulting solution using an evaporator, and the resulting solution was poured into 800 parts by weight of pure water. The precipitate was filtered and then vacuum dried to obtain the active ester compound, thermosetting compound Y10.

[0216] Thermosetting compound Y11: Using a vessel equipped with a stirrer, reflux condenser, and Dean-Stark water separator, 21.1 parts by weight of trimellitic anhydride chloride was dissolved in 200 parts by weight of N-methyl-2-pyrrolidone. To the resulting solution, 14.4 parts by weight of 2-naphthol and 10.1 parts by weight of triethylamine were added, and the mixture was stirred at 25°C for 4 hours to react. 14.6 parts by weight of 1,3-bis(3-aminophenoxy)benzene was added to the resulting reaction solution, and the mixture was stirred at 25°C for 4 hours to react. 200 parts by weight of toluene was added to the resulting solution, and the mixture was refluxed at 150°C for 4 hours until no more water was generated. After the reaction was complete, the toluene was removed from the resulting solution using an evaporator, and the resulting solution was poured into 800 parts by weight of pure water. The precipitate was filtered and then vacuum dried to obtain the active ester compound, thermosetting compound Y11. The equivalent weight of thermosetting compound Y11 was 446.

[0217] Details of the thermosetting compounds X1 to X7 and Y1 to Y3 are shown in Tables 1 and 2 below.

[0218] [Table 1]

[0219] [Table 2]

[0220] (Inorganic filler) Silica-containing slurry (75% by weight of silica: Admatechs "SC4050-HOA", average particle size 1.0 μm, aminosilane treatment, cyclohexanone 25% by weight)

[0221] (curing accelerator) Dimethylaminopyridine ("DMAP" manufactured by Wako Pure Chemical Industries, Ltd.)

[0222] (thermoplastic resin) Phenoxy resin (Mitsubishi Chemical Corporation "YX6954BH30", solid content 30% by weight) Polyimide resin: Polyimide resin (synthetic product) prepared according to the following synthesis example.

[0223] (Synthesis example) A reaction vessel equipped with a stirrer, a water divider, a thermometer, and a nitrogen gas inlet tube was charged with 300.0 g of tetracarboxylic dianhydride (SABIC Japan G.K., "BisDA-1000") and 665.5 g of cyclohexanone, and the solution was heated to 60°C. Next, 89.0 g of dimer diamine (Croda Japan, "PRIAMINE 1075") and 54.7 g of 1,3-bisaminomethylcyclohexane (Mitsubishi Gas Chemical Company, Inc.) were added dropwise. Subsequently, 121.0 g of methylcyclohexane and 423.5 g of ethylene glycol dimethyl ether were added, and the imidization reaction was carried out at 140°C for 10 hours, yielding a polyimide solution (nonvolatile content: 26.8 wt%). The molecular weight (weight average molecular weight) of the resulting polyimide was 20,000.

[0224] (Examples 1 to 7, Reference Example 8, Example 9 , Reference Examples 10 and 11, Example 12 ~19 and Comparative Examples 1 to 3) The components shown in Tables 3 to 5 below were mixed in the amounts (unit: parts by weight of solid content) shown in Tables 3 to 5 below, and stirred at room temperature until a uniform solution was obtained, to obtain a resin material.

[0225] Preparation of resin film: The obtained resin material was applied to the release-treated surface of a release-treated PET film (Toray Industries, Inc., "XG284," 25 μm thick) using an applicator, and then dried for 2 minutes and 30 seconds in a gear oven at 100°C to volatilize the solvent. In this way, a laminated film (a laminated film of PET film and resin film) was obtained in which a 40 μm-thick resin film (B-stage film) was laminated on the PET film.

[0226] (evaluation) (1) Blistering of the cured product during reflow testing after baking (1-1) Substrate preparation: Lamination process and semi-curing process: A double-sided copper-clad laminate (CCL substrate) (copper foil thickness on each side: 18 μm, substrate thickness: 0.7 mm, substrate size: 100 mm × 100 mm, Hitachi Chemical Co., Ltd. "MCL-E-679FG(R)") was prepared. Both copper foil surfaces of this double-sided copper-clad laminate were immersed in MEC Co., Ltd.'s "Cz8101" to roughen the copper foil surface. The resin film (B-stage film) side of the laminate film was laminated onto both sides of the roughened copper-clad laminate using a Meiki Seisakusho Co., Ltd. "Batch Vacuum Laminator MVLP-500-IIA" to obtain a laminate structure. Lamination was performed by reducing the pressure to 13 hPa or less for 30 seconds, laminating at 100°C and a pressure of 0.7 MPa for 30 seconds, and then pressing at 100°C and a pressure of 0.8 MPa for 60 seconds. The PET film was then peeled off, and the resin film was semi-cured by heating at 100°C for 30 minutes and then at 180°C for an additional 30 minutes, yielding a laminate in which a semi-cured resin film was laminated on a CCL substrate.

[0227] Roughening and desmearing: (a) Swelling treatment: The resulting laminate was placed in a swelling liquid (Swelling Dip Securigant P, manufactured by Atotech Japan) at 60°C and shaken for 10 minutes, after which it was washed with pure water.

[0228] (b) Permanganate treatment (roughening and desmearing): The laminate after swelling treatment was placed in a roughening aqueous solution of potassium permanganate ("Concentrate Compact CP" manufactured by Atotech Japan) at 80°C and shaken for 30 minutes. Next, it was treated with a cleaning solution ("Reduction Securigant P" manufactured by Atotech Japan) at 25°C for 2 minutes, and then washed with pure water to obtain a laminate after desmear treatment.

[0229] Electroless plating process: The surface of the cured product of the resulting desmeared laminate was treated with an alkaline cleaner (Atotech Japan's "Cleaner Securigant 902") at 60°C for 5 minutes to degrease and clean. After cleaning, the cured product was treated with a pre-dip solution (Atotech Japan's "Pre-dip Neogant B") at 25°C for 2 minutes. The cured product was then treated with an activator solution (Atotech Japan's "Activator Neogant 834") at 40°C for 5 minutes to attach a palladium catalyst. Next, the cured product was treated with a reducing solution (Atotech Japan's "Reducer Neogant WA") at 30°C for 5 minutes.

[0230] Next, the cured product was placed in a chemical copper solution (Atotech Japan's "Basic Printganth MSK-DK," "Copper Printganth MSK," "Stabilizer Printganth MSK," and "Reducer Cu") and electroless plating was performed until the plating thickness reached approximately 0.5 μm. After electroless plating, the product was annealed at 120°C for 30 minutes to remove any remaining hydrogen gas. All steps up to the electroless plating step were performed using 2 L of treatment solution in a beaker while the cured product was being shaken.

[0231] Electrolytic plating process: Next, the electroless plated cured product was subjected to electrolytic plating until the plating thickness reached 25 μm. For the electrolytic copper plating, a copper sulfate solution ("Copper sulfate pentahydrate" manufactured by Wako Pure Chemical Industries, Ltd., "Sulfuric acid" manufactured by Wako Pure Chemical Industries, Ltd., "Basic Leveler Cupracid HL" manufactured by Atotech Japan, and "Correction Agent Cupracid GS" manufactured by Atotech Japan) was used, and the plating was conducted at 0.6 A / cm. 2 Electrolytic plating was carried out by passing a current of 1000 kJ / min until the plating thickness reached approximately 25 μm. After the copper plating treatment, the cured product was heated at 200°C for 90 minutes to further harden the cured product. In this way, a cured product having a copper plating layer laminated on the upper surface was obtained.

[0232] Baking process: The resulting cured product with the copper plating layer on top was cut into 85 mm squares and baked at 125°C to obtain cured products 1 hour, 2 hours, and 6 hours after the start of baking. The resulting cured products were evaluated for swelling. Specifically, the following reflow test was performed.

[0233] (2-2) Reflow test Using the cured product laminated with the copper plating layer after baking, the substrate was subjected to moisture absorption (40 hours at a temperature of 60°C and a humidity of 60% RH) in accordance with JEDEC Level 3. A reflow test (reflow temperature profile conforming to IPC / JEDEC J-STD-020C) was performed using a reflow device (Japan Antom Co., Ltd., "HAS-6116") that reproduces a solder reflow temperature with a peak temperature of 260°C. The reflow was repeated 10 times. The presence or absence of blisters after reflow was visually confirmed.

[0234] [Criteria for determining swelling of cured products after reflow testing after baking] ○: No blistering after 10 reflows ×: Blisters occurred after 1 to 9 reflow cycles

[0235] [Comprehensive evaluation of swelling of cured product after reflow test after baking] ○○: The result after 1 hour of baking is ○ ○: The result of 2 hours of baking is ○ △: The result after 6 hours of baking is ○ ×: The result of 6 hours of baking is ×

[0236] (2) Warpage of the cured product The resulting laminate film was cut to a size of 50 mm x 50 mm. The cut laminate film was placed on a copper plate (50 mm x 50 mm x 100 μm thick) with the resin film side facing up, and then the pressure was reduced for 30 seconds using a diaphragm-type vacuum laminator ("Batch-type Vacuum Laminator MVLP-500-IIA" manufactured by Meiki Seisakusho Co., Ltd.) to 13 hPa or less, followed by lamination at 100°C and a pressure of 0.7 MPa for 30 seconds. In this way, a laminate was obtained in which the laminate film (uncured resin film and PET film) was laminated on the copper plate.

[0237] The PET film was peeled off, and the resulting laminate was heated at 100°C for 30 minutes, followed by an additional 30 minutes at 180°C. It was then heated at 200°C for 90 minutes. In this way, a laminate was obtained in which a cured resin film was laminated on a copper plate. The laminate was placed on a flat glass with the copper plate on the bottom and the cured product on the top, and the degree of warping at the four corners was measured. The distance from the top surface of the flat glass to each of the four corners was taken as the amount of warping, and the average amount of warping at the four corners was calculated. The warping of the cured product was evaluated according to the following criteria.

[0238] [Criteria for determining warpage of cured products] ○○: Average warpage is 3mm or less ○: Average warpage is over 3 mm and 5 mm or less △: Average warpage is over 5mm and 10mm or less ×: The average amount of warpage exceeds 10 mm

[0239] (3) Dielectric tangent The resulting resin film was heated at 100°C for 30 minutes, then further heated at 180°C for 30 minutes. Further heating at 200°C for 90 minutes yielded a cured product. The resulting cured product was cut into a size of 2 mm wide and 80 mm long, and 10 sheets were stacked together. The dielectric loss tangent was measured at room temperature (23°C) and a frequency of 5.8 GHz by the cavity resonance method using a CP521 cavity resonance perturbation dielectric constant measuring device manufactured by Kanto Electronics Application Development Co., Ltd. and a N5224A PNA network analyzer manufactured by Keysight Technologies.

[0240] [Criteria for determining dielectric loss tangent] ○: Dielectric tangent is 3.5×10 -3 below △: Dielectric loss tangent is 3.5×10 -3 Exceeds 4.0 x 10 -3 below ×: Dielectric tangent is 4.0×10 -3 exceed

[0241] The compositions and results are shown in Tables 3 to 5 below.

[0242] [Table 3]

[0243] [Table 4]

[0244] [Table 5] [Explanation of symbols]

[0245] 11...Multilayer printed wiring board 12...Circuit board 12a…Top surface 13~16...Insulating layer 17...Metal layer

Claims

1. The structural portion excluding the thermosetting functional group does not have an aromatic ring, and the structural portion excluding the thermosetting functional group has two or more CH ３ a first thermosetting compound having a terminal and satisfying the following formula (X): a second thermosetting compound; and and an inorganic filler, the first thermosetting compound is an epoxy compound, The second thermosetting compound is 1) a thermosetting compound having an aromatic ring in the structural portion excluding the thermosetting functional group, 2A) a thermosetting compound having no CH 3 terminal in the structural portion excluding the thermosetting functional group, 2B) a thermosetting compound having one CH 3 terminal in the structural portion excluding the thermosetting functional group, 3A) a thermosetting compound satisfying the following formula (Y1), or 3B) a thermosetting compound satisfying the following formula (Y2): The content of the inorganic filler is 30% by weight or more based on 100% by weight of components excluding the solvent in the resin material, the content of the first thermosetting compound is 10% by weight or more and 50% by weight or less based on 100% by weight of components in the resin material excluding the inorganic filler and the solvent, Resin materials (excluding resin materials containing layered silicates) used to form insulating layers in multilayer printed wiring boards. 0.1≦A / (B×C)≦0.6 ...Formula (X) A: CH 3 contained in the structural portion of the first thermosetting compound other than the thermosetting functional group ３ Number of ends B: the number of thermosetting functional groups contained in the first thermosetting compound C: the number of carbon atoms in the structural portion of the first thermosetting compound excluding the thermosetting functional group A' / (B'×C')<0.1...Formula (Y1) A' / (B'×C')>0.6 Formula (Y2) In the formula (Y1) and the formula (Y2), A', B' and C' have the following meanings. A': the number of CH 3 ends in the structural portion of the second thermosetting compound excluding the thermosetting functional group B': the number of thermosetting functional groups contained in the second thermosetting compound C': the number of carbon atoms in the structural portion of the second thermosetting compound excluding the thermosetting functional group

2. the first thermosetting compound has a tert-butyl group in a structural portion other than the thermosetting functional group, The resin material according to claim 1, wherein the number of tert-butyl groups contained in the structural portion of the first thermosetting compound other than the thermosetting functional group is one or more.

3. The resin material according to claim 1 or 2, wherein the number of carbon atoms contained in the structural portion of the first thermosetting compound excluding the thermosetting functional group is 5 or more and 30 or less.

4. The resin material according to any one of claims 1 to 3, wherein the number of thermosetting functional groups possessed by the first thermosetting compound is one or two.

5. The resin material according to any one of claims 1 to 4, wherein the number of thermosetting functional groups possessed by the first thermosetting compound is one.

6. The resin material according to any one of claims 1 to 5, wherein a structural portion of the first thermosetting compound other than the thermosetting functional group has a branched structure.

7. a structural portion of the first thermosetting compound other than the thermosetting functional group has a branched structure, 7. The resin material according to claim 1, wherein the ratio of the number of carbon atoms in the chain having the largest number of atoms in the structural portion excluding the thermosetting functional group of the first thermosetting compound to the total number of carbon atoms in the structural portion excluding the thermosetting functional group of the first thermosetting compound is 40% or more and 90% or less.

8. The resin material according to any one of claims 1 to 7, which is a resin film.

9. A circuit board; a plurality of insulating layers disposed on a surface of the circuit board; a metal layer disposed between a plurality of the insulating layers; A multilayer printed wiring board, wherein at least one of the plurality of insulating layers is a cured product of the resin material according to any one of claims 1 to 8.

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