Method for manufacturing circuit board

Abstract

The purpose of the present invention is to provide a method for manufacturing a circuit board with which it is possible to further reduce the center-to-center distance between holes. This method for manufacturing a circuit board comprises: (I) a step for preparing a resin sheet with a support including the support and a resin composition layer provided on the support; (II) a step for laminating the resin sheet with the support on a substrate; (III) a step for thermally curing the resin composition layer to form an insulating layer; and (IV) a step for continuously forming N (N is an integer of 3 or more) holes in the support and the insulating layer using a laser. In the method for manufacturing a circuit board, step (IV) includes: (IV -1) a step for forming a first hole, which is a hole to be formed first; (IV -2) a step for forming a second hole, which is a hole to be formed second; and (IV -3) a step for forming an n-th hole, which is a hole to be formed n-th (n is an integer satisfying 3 ≤ n ≤ N). When the opening diameter of the insulating layer of the first hole is defined as r1 (µm), and the distance from the center of the first hole to the center of the second hole is defined as S1 (µm), the second hole is formed at a position satisfying the relationship S1 ≥ 3r1, and when the opening diameter of the insulating layer of the n-1th hole is defined as rn-1 (µm), and the distance from the center of the first hole to the center of the nth hole is defined as Sn-1 (µm), the nth hole is formed at a position satisfying the relationship of Sn-1 ≥ 3rn-1, and at least one of the nth holes from the third hole to the N-th hole to be formed the N-th time is formed inside a circle having the maximum center-to-center distance of the formed plurality of holes as the diameter.

Description

Circuit board manufacturing method

[0001] This invention relates to a method for manufacturing a circuit board.

[0002] Circuit boards, widely used in various electronic devices, require miniaturization and high density of circuit wiring to achieve miniaturization and enhanced functionality in electronic devices. One manufacturing technology for circuit boards involves laminating a resin sheet with a support containing a support and a resin composition layer onto an inner layer substrate, thermally curing the resin composition layer to form an insulating layer, and then using a laser to drill holes in the insulating layer to form via holes and other holes (see Patent Documents 1 and 2).

[0003] Patent No. 6503633, Patent No. 5588683

[0004] In recent years, there has been a growing demand for finer and higher-density circuit wiring on circuit boards. Therefore, it is necessary to reduce the distance between the centers of multiple via holes and other similar holes.

[0005] Through diligent research, the inventors discovered that heat generated by laser irradiation is transferred to the support material, making the area around the hole more suitable for laser drilling. They also found that this effect is particularly pronounced when the support material contains either polyethylene terephthalate or polyethylene naphthalate.

[0006] When forming holes with a narrower distance between their centers, attempting to create a hole adjacent to a previously drilled hole means creating the hole in a location where heat from the laser irradiation is being transferred to the support. In this state, creating a hole adjacent to a previously drilled hole increases the diameter of the support opening in that hole, which in turn increases the diameter of the insulating layer opening, making it impossible to narrow the distance between the centers of the holes.

[0007] This invention was devised in view of the above-mentioned problems, and aims to provide a method for manufacturing a circuit board that can reduce the distance between the centers of the holes.

[0008] In other words, the present invention includes the following: [1] A method for manufacturing a circuit board, comprising the steps of: (I) preparing a resin sheet with a support including a support and a resin composition layer provided on the support; (II) laminating the resin sheet with the support onto a substrate; (III) thermally curing the resin composition layer to form an insulating layer; and (IV) continuously forming N holes (N is an integer of 3 or more) in the support and the insulating layer using a laser, wherein step (IV) includes (IV-1) forming a first hole which is the first hole to be formed; (IV-2) forming a second hole which is the second hole to be formed; and (IV-3) forming the nth hole which is the nth hole to be formed (n is an integer satisfying 3 ≤ n ≤ N), and the second hole is formed with an opening diameter of r of the insulating layer of the first hole １ Let (μm) be the distance from the center of the first hole to the center of the second hole, and S be the distance from the center of the first hole to the center of the second hole. １ When (μm), S １ ≥3r １ The nth hole is formed at a position that satisfies the following relationship, and the opening diameter of the insulating layer of the (n-1)th hole is r ｎ－１ Let (μm) be the distance from the center of the (n-1)th hole to the center of the nth hole, and S be the distance from the center of the (n-1)th hole to the center of the nth hole. ｎ－１ When (μm), S ｎ－１ ≥3r ｎ－１A method for manufacturing a circuit board, wherein the holes are formed at positions that satisfy the following relationship, and at least one of the nth holes from the third hole to the nth hole formed as the nth hole is formed inside a circle whose diameter is the maximum intercenter distance among the intercenter distances between the already formed plurality of holes. [2] A method for manufacturing a circuit board according to [1], wherein the resin composition layer comprises (a) an inorganic filler and (b) a thermosetting resin. [3] A method for manufacturing a circuit board according to [2], wherein the content of component (a) is 60% by mass or more and 80% by mass or less when the nonvolatile components contained in the resin composition layer are taken as 100% by mass. [4] A method for manufacturing a circuit board according to any one of [1] to [3], wherein the degree of curing of the insulating layer before the post-processing (IV) after process (III) is 40% or more. [5] A method for manufacturing a circuit board according to any one of [1] to [4], wherein the aperture diameter of the insulating layer of the nth hole formed is 150 μm or less. [6] The method for manufacturing a circuit board according to any one of [1] to [5], wherein the opening diameter of the support for the nth hole formed is 150 μm or less. [7] The method for manufacturing a circuit board according to any one of [1] to [6], wherein the distance from the center of the first hole to the center of the nth hole formed inside a circle whose diameter is the maximum distance between centers is 200 μm or less. [8] The method for manufacturing a circuit board according to any one of [1] to [7], wherein the distance from the center of the first hole to the center of the nth hole formed inside a circle whose diameter is the maximum distance between centers is shorter than the distance from the center of the first hole to the center of the second hole.

[0009] According to the present invention, it is possible to provide a method for manufacturing a circuit board that can reduce the distance between the centers of adjacent holes.

[0010] Figure 1 is a cross-sectional view showing an example of the state immediately after the first hole has been formed on the support and the insulating layer. Figure 2 is a cross-sectional view showing an example of the state after the second hole has been formed after the first hole has been formed. Figure 3 is a schematic top view showing the state of the first embodiment as an example of process (IV). Figure 4 is a schematic top view showing the state of the first embodiment as an example of process (IV). Figure 5 is a schematic top view showing the state of the first embodiment as an example of process (IV). Figure 6 is a schematic top view showing the state of the first embodiment as an example of process (IV). Figure 7 is a schematic top view showing the state of the first embodiment as an example of process (IV). Figure 8 is a schematic top view showing the state of the first embodiment as an example of process (IV). Figure 9 is a schematic top view showing the state of the first embodiment as an example of process (IV). Figure 10 is a schematic top view showing the state of the first embodiment as an example of process (IV). Figure 11 is a schematic top view showing the first embodiment as an example of process (IV). Figure 12 is a schematic top view showing the first embodiment as an example of process (IV). Figure 13 is a schematic top view showing the first embodiment as an example of process (IV). Figure 14 is a schematic top view showing the second embodiment as an example of process (IV). Figure 15 is a schematic top view showing the second embodiment as an example of process (IV). Figure 16 is a schematic top view showing the second embodiment as an example of process (IV). Figure 17 is a schematic top view showing the second embodiment as an example of process (IV). Figure 18 is a schematic top view showing the second embodiment as an example of process (IV). Figure 19 is a schematic top view showing the third embodiment as an example of process (IV). Figure 20 is a schematic top view showing a third embodiment as an example of process (IV). Figure 21 is a schematic top view showing a third embodiment as an example of process (IV). Figure 22 is a schematic top view showing a third embodiment as an example of process (IV). Figure 23 is a schematic top view showing a third embodiment as an example of process (IV).FIG. 24 is a top view schematically illustrating the state of a third embodiment as an example of step (IV). FIG. 25 is a top view schematically illustrating the state of the third embodiment as an example of step (IV). FIG. 26 is a top view schematically illustrating the state of the third embodiment as an example of step (IV). FIG. 27 is a top view schematically illustrating the state of the third embodiment as an example of step (IV). FIG. 28 is a top view schematically illustrating the state of the third embodiment as an example of step (IV).

[0011] Hereinafter, the present invention will be described in detail with reference to embodiments and examples. However, the present invention is not limited to the following embodiments and examples, and can be arbitrarily modified and implemented without departing from the scope of the claims of the present invention and the scope of equivalents thereof.

[0012] [Method for Manufacturing Circuit Board] The method for manufacturing a circuit board of the present invention comprises: (I) a step of preparing a resin sheet with a support comprising a support and a resin composition layer provided on the support; (II) a step of laminating the resin sheet with a support onto a base material; (III) a step of thermally curing the resin composition layer to form an insulating layer; and (IV) a step of continuously forming N holes (N is an integer of 3 or more) in the support and the insulating layer by laser, wherein step (IV) comprises: (IV-1) a step of forming a first hole that is the first hole to be formed; (IV-2) a step of forming a second hole that is the second hole to be formed; and (IV-3) a step of forming an n-th hole that is the n-th hole to be formed (n is an integer satisfying 3≤n≤N), wherein the second hole has an opening diameter of r in the insulating layer of the first hole １ (μm), and the distance from the center of the first hole to the center of the second hole is S １ (μm), S １ ≧3r １ The n-th hole is formed at a position satisfying the above relationship, and the n-th hole has an opening diameter of r in the insulating layer of the (n-1)-th hole ｎ－１ (μm), and the distance from the center of the (n-1)-th hole to the center of the n-th hole is S ｎ－１ (μm), S ｎ－１ ≧3r ｎ－１The holes are formed at positions that satisfy the following relationship, and at least one of the nth holes from the third hole to the nth hole formed as the Nth hole is formed inside a circle whose diameter is the maximum inter-center distance among the inter-center distances between the already formed multiple holes. According to the manufacturing method of the circuit board of the present invention, the distance between the centers of the holes can be made narrower.

[0013] The method for manufacturing a circuit board according to the present invention is preferably carried out in the order of step (I), step (II), step (III), and step (IV).

[0014] The method for manufacturing a circuit board of the present invention may include, in addition to steps (I) to (IV), one or more of the following steps after step (IV): (V) peeling the support from the resin sheet with the support, (VI) roughening the insulating layer, and (VII) forming the conductive layer. Each step of the method for manufacturing a circuit board will be described in detail below.

[0015] <Step (I)> In Step (I), a resin sheet with a support is prepared, which includes a support and a resin composition layer provided on the support. The layers of the resin sheet with a support will be described below.

[0016] <<Support>> The resin sheet with a support has a support. A film made of a plastic material (hereinafter also simply referred to as "plastic film") is preferably used as the support. Examples of plastic materials include polyethylene terephthalate ("PET"), polyethylene naphthalate ("PEN"), polycarbonate ("PC"), polymethyl methacrylate (PMMA), cyclic polyolefin, triacetylcellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide, etc. As the plastic film, either polyethylene terephthalate or polyethylene naphthalate is preferred, and polyethylene terephthalate is more preferred.

[0017] The support may have surface treatments such as matte finish, corona treatment, or antistatic treatment applied to the surface that bonds with the resin composition layer.

[0018] As the support, a support with a release layer may be used, which has a release layer on the surface that is bonded to the resin composition layer. Examples of release agents used in the release layer of the support with a release layer include one or more release agents selected from the group consisting of alkyd-based release agents, polyolefin-based release agents, urethane-based release agents, and silicone-based release agents. Commercially available products may be used as the support with a release layer, for example, PET films having a release layer mainly composed of a silicone-based release agent or an alkyd resin-based release agent, such as "PET501010", "SK-1", "AL-5", and "AL-7" from Lintec Corporation; "Lumirror T60" from Toray Industries, Inc.; "Purex" from Teijin Corporation; and "Unipeel" from Unitika Corporation.

[0019] The thickness of the support is not particularly limited, but is preferably 1 μm or more, more preferably 2 μm or more, even more preferably 5 μm or more, preferably 75 μm or less, more preferably 60 μm or less, and even more preferably 50 μm or less. When using a support with a release layer, it is preferable that the overall thickness of the support with the release layer is within the above range.

[0020] <<Resin Composition Layer>> The resin sheet with support has a resin composition layer. The resin composition layer can form an insulating layer by heat curing. Typically, the insulating layer includes a cured product of the resin composition layer, and preferably includes only a cured product of the resin composition layer.

[0021] The resin composition layer only needs to have sufficient hardness and insulating properties when cured. From the viewpoint of obtaining an insulating layer with a low coefficient of linear thermal expansion (CTE) that can reduce the distance between the centers of holes, the resin composition layer includes (a) an inorganic filler and (b) a thermosetting resin. The resin composition layer may also optionally include (c) a thermoplastic resin, (d) a curing accelerator, (e) an organic filler, (f) a flame retardant, (g) any additive, and (h) a solvent. The following describes each component that can be included in the resin composition layer.

[0022] In the present invention, unless otherwise specified, the content of each component in the resin composition layer is the value when the non-volatile component in the resin composition layer is taken as 100% by mass, and the non-volatile component refers to the components of the resin composition layer other than the solvent described later. Furthermore, in the present invention, the resin component of the resin composition layer refers to the components of the resin composition layer excluding the inorganic filler from the non-volatile components.

[0023] - (a) Inorganic Filler - The resin composition contains (a) an inorganic filler as component (a). By incorporating (a) an inorganic filler into the resin composition, an insulating layer can be obtained that has a low coefficient of linear thermal expansion and can narrow the distance between the centers of holes. (a) The inorganic filler may be used alone or in combination of two or more types.

[0024] (a) Inorganic compounds are used as the material for the inorganic filler. Examples of inorganic filler materials include silica, alumina, aluminosilicate, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among these, calcium carbonate and silica are preferred, and silica is particularly preferred. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, and hollow silica. Spherical silica is preferred as the silica.

[0025] (a) Examples of commercially available components include "SP60-05" and "SP507-05" from Nippon Steel Chemical & Material Co., Ltd.; "YC100C", "YA050C", "YA050C-MJE", "YA010C", "SC2500SQ", "SO-C4", "SO-C2", and "SO-C1" from Admatex Co., Ltd.; "UFP-30", "DAW-03", and "FB-105FD" from Denka Co., Ltd.; "Silfil NSS-3N", "Silfil NSS-4N", and "Silfil NSS-5N" from Tokuyama Corporation; and "Cellspheres" and "MGH-005" from Taiheiyo Cement Corporation.

[0026] (a) The specific surface area of ​​component is preferably 1 m². ２ / g or more, more preferably 2m ２ / g or more, particularly preferably 3m ２ It is 1 / g or more. There is no particular upper limit, but preferably 60m ２ / g or less, 50m ２ / g or less or 40m ２ The value is less than or equal to / g. The specific surface area is obtained by adsorbing nitrogen gas onto the sample surface using a specific surface area measuring device (Macorb HM-1210, manufactured by Mountec Co., Ltd.) according to the BET method, and then calculating the specific surface area using the BET multipoint method.

[0027] (a) The average particle size of component is preferably 0.01 μm or more, more preferably 0.05 μm or more, even more preferably 0.1 μm or more, preferably 5 μm or less, more preferably 4 μm or less, and even more preferably 3 μm or less.

[0028] (a) The average particle size of component (a) can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, a volume-based particle size distribution of the inorganic filler can be created using a laser diffraction / scattering particle size distribution analyzer, and the median diameter can be used as the average particle size. A sample can be prepared by weighing 100 mg of inorganic filler and 10 g of methyl ethyl ketone into a vial and dispersing them with ultrasound for 10 minutes. The sample can be measured using a laser diffraction particle size distribution analyzer with blue and red light source wavelengths, and the volume-based particle size distribution of component (a) can be measured using a flow cell method. The average particle size can then be calculated as the median diameter from the obtained particle size distribution. An example of a laser diffraction particle size distribution analyzer is the "LA-960" manufactured by Horiba, Ltd.

[0029] (a) Component is preferably treated with a surface treatment agent from the viewpoint of improving moisture resistance and dispersibility. Examples of surface treatment agents include vinylsilane coupling agents, (meth)acrylic coupling agents, fluorine-containing silane coupling agents, aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, alkoxysilanes, organosilazane compounds, titanate coupling agents, etc. Among these, aminosilane coupling agents are preferred from the viewpoint of obtaining the effects of the present invention in particular. Furthermore, one type of surface treatment agent may be used alone, or two or more types may be used in any combination.

[0030] Examples of commercially available surface treatment agents include Shin-Etsu Chemical Co., Ltd.'s "KBM-1003" (vinyltriethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM-503" (3-methacryloxypropyltriethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM-403" (3-glycidoxypropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM-803" (3-mercaptopropyltrimethoxysilane), and Shin-Etsu Chemical Co., Ltd.'s "KBE-903" (3-aminopropyltriethoxysilane). Examples include toxysilane, Shin-Etsu Chemical Co., Ltd.'s "KBM-573" (N-phenyl-3-aminopropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "SZ-31" (hexamethyldisilazane), Shin-Etsu Chemical Co., Ltd.'s "KBM103" (phenyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM-4803" (long-chain epoxy type silane coupling agent), Shin-Etsu Chemical Co., Ltd.'s "KBM-7103" (3,3,3-trifluoropropyltrimethoxysilane), etc.

[0031] From the viewpoint of improving the dispersibility of the inorganic filler, the degree of surface treatment with the surface treatment agent is preferably within a predetermined range. Specifically, it is preferable that the inorganic filler is surface-treated with 0.2% to 5% by mass of the surface treatment agent, preferably 0.2% to 3% by mass, and preferably 0.3% to 2% by mass, based on 100% by mass of the inorganic filler.

[0032] The degree of surface treatment by a surface treatment agent can be evaluated by the amount of carbon per unit surface area of ​​the inorganic filler. From the viewpoint of improving the dispersibility of the inorganic filler, the amount of carbon per unit surface area of ​​the inorganic filler should be 0.02 mg / m². ２ The above is preferred, and 0.1 mg / m² ２ The above is more preferable, 0.2 mg / m² ２ The above is even more preferable. On the other hand, from the viewpoint of suppressing the increase in the melt viscosity of the resin varnish and the melt viscosity in sheet form, 1 mg / m ２ The following is preferred: 0.8 mg / m² ２ The following is more preferable: 0.5 mg / m² ２ The following is even more preferable.

[0033] (a) The amount of carbon per unit surface area of ​​an inorganic filler can be measured after cleaning the inorganic filler with a solvent (e.g., methyl ethyl ketone (MEK)) following surface treatment. Specifically, a sufficient amount of MEK as the solvent is added to the inorganic filler that has been surface-treated with a surface treatment agent, and ultrasonic cleaning is performed at 25°C for 5 minutes. After removing the supernatant and drying the solids, the amount of carbon per unit surface area of ​​the inorganic filler can be measured using a carbon analyzer. As a carbon analyzer, the "EMIA-320V" manufactured by Horiba, Ltd. can be used.

[0034] (a) The content of component (a) is preferably 60% by mass or more, more preferably 61% by mass or more, and even more preferably 62% by mass or more, when the nonvolatile components in the resin composition layer are taken as 100% by mass. The upper limit is preferably 85% by mass or less, more preferably 80% by mass or less, and even more preferably 78% by mass or less. If the insulating layer contains a large amount of inorganic filler (a), the amount of heat generated when forming holes with a laser will increase. If a hole is formed immediately after a hole has been formed, at a position adjacent to the hole, the opening diameter of the support in the hole will become larger, and consequently the opening diameter of the insulating layer will also become larger, making it impossible to narrow the distance between the centers of the holes. However, in the present invention, since step (IV) described later is performed, the distance between the centers of the holes can be narrowed even if the insulating layer contains a large amount of inorganic filler (a).

[0035] - (b) Curable resin - The resin composition layer contains (b) thermosetting resin as component (b). This (b) thermosetting resin as component (b) excludes those that fall under component (a). The type of (b) thermosetting resin is not particularly limited as long as it can be cured by heat. (b) thermosetting resin may be used alone or in combination of two or more types.

[0036] (b) The thermosetting resin preferably has a functional group that can undergo thermosetting. Examples of functional groups include epoxy groups; radical polymerizable unsaturated groups such as maleimide groups, vinyl groups, allyl groups, styryl groups, vinylphenyl groups, acryloyl groups, methacryloyl groups, fumaroyl groups, and maleoil groups; etc. (b) The functional group that the thermosetting resin has preferably is one of epoxy groups, maleimide groups, and styryl groups, with epoxy groups being more preferable. It is also preferable that there are two or more functional groups in one molecule.

[0037] (b) As the thermosetting resin, for example, (b-1) epoxy resin and (b-2) curing agent can be used. (b) Preferably, the thermosetting resin contains (b-1) epoxy resin and (b-2) curing agent.

[0038] --(b-1) Epoxy Resin-- (b) The epoxy resin as component (b-1) refers to a thermosetting resin having epoxy groups. (b-1) epoxy resin may be used alone or in combination of two or more types.

[0039] (b-1) Examples of epoxy resins include bixylenol-type epoxy resin, bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, bisphenol AF-type epoxy resin, dicyclopentadiene-type epoxy resin, trisphenol-type epoxy resin, naphthol novolac-type epoxy resin, phenol novolac-type epoxy resin, tert-butyl-catechol-type epoxy resin, naphthalene-type epoxy resin, naphthol-type epoxy resin, anthracene-type epoxy resin, glycidylamine-type epoxy resin, and glycidyl ester. Examples include epoxy resins of the following types: glycidylcyclohexane type epoxy resin, alkyldiglycidyl ether type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, epoxy resin having a butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, spiroring-containing epoxy resin, cyclohexane type epoxy resin, cyclohexanedimethanol type epoxy resin, naphthylene ether type epoxy resin, trimethylol type epoxy resin, tetraphenylethane type epoxy resin, phenolphthaleimidine type epoxy resin, and the like.

[0040] The resin composition layer preferably contains an epoxy resin having two or more epoxy groups in one molecule as component (b-1). From the viewpoint of significantly obtaining the desired effects of the present invention, the ratio of the epoxy resin having two or more epoxy groups in one molecule to 100% by mass of the epoxy resin (b-1) is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

[0041] (b-1) Epoxy resins include epoxy resins that are liquid at 20°C (hereinafter sometimes referred to as "liquid epoxy resins") and epoxy resins that are solid at 20°C (hereinafter sometimes referred to as "solid epoxy resins"). The resin composition layer may contain only liquid epoxy resin as component (b-1), only solid epoxy resin, or a combination of liquid epoxy resin and solid epoxy resin. In particular, from the viewpoint of obtaining the effects of the present invention in a remarkable manner, it is preferable to contain a combination of liquid epoxy resin and solid epoxy resin.

[0042] As the liquid epoxy resin, a liquid epoxy resin having two or more epoxy groups in one molecule is preferred.

[0043] Preferred liquid epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, phenol novolac type epoxy resin, alicyclic epoxy resin having an ester skeleton, cyclohexane type epoxy resin, cyclohexanedimethanol type epoxy resin, glycidylamine type epoxy resin, and epoxy resin having a butadiene structure, glycidylcyclohexane type epoxy resin, phenolphthaleimidine type epoxy resin, and alkyl diglycidyl ether type epoxy resin, with bisphenol A type epoxy resin and bisphenol F type epoxy resin being more preferred.

[0044] Specific examples of liquid epoxy resins include DIC Corporation's "HP4032," "HP4032D," and "HP4032SS" (naphthalene-type epoxy resin); Mitsubishi Chemical Corporation's "828US," "jER828EL," "825," and "Epicote 828EL" (bisphenol A-type epoxy resin); Mitsubishi Chemical Corporation's "jER807" and "1750" (bisphenol F-type epoxy resin); Mitsubishi Chemical Corporation's "jER152" (phenol novolac-type epoxy resin); Mitsubishi Chemical Corporation's "630" and "630LSD" (glycidylamine-type epoxy resin); and Nippon Steel Chemical & Material Corporation's "ZX1 Examples include "059" (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin); "EX-721" (glycidyl ester type epoxy resin) manufactured by Nagase ChemteX Corporation; "Celoxide 2021P" (alicyclic epoxy resin with an ester skeleton) manufactured by Daicel Corporation; "PB-3600" (epoxy resin with a butadiene structure) manufactured by Daicel Corporation; "ZX1658" and "ZX1658GS" (liquid 1,4-glycidylcyclohexane type epoxy resin) manufactured by Nippon Steel Chemical & Material Corporation; and "YED216D" (alkyl diglycidyl ether type epoxy resin) manufactured by Mitsubishi Chemical Corporation. These may be used individually or in combination of two or more types.

[0045] As the solid epoxy resin, a solid epoxy resin having two or more epoxy groups per molecule is preferred, a solid epoxy resin having three or more epoxy groups per molecule is more preferred, and an aromatic solid epoxy resin having three or more epoxy groups per molecule is even more preferred.

[0046] Preferred solid epoxy resins include bixylenol-type epoxy resin, naphthalene-type epoxy resin, naphthalene-type tetrafunctional epoxy resin, cresol novolac-type epoxy resin, dicyclopentadiene-type epoxy resin, trisphenol-type epoxy resin, naphthol-type epoxy resin, biphenyl-type epoxy resin, naphthylene ether-type epoxy resin, anthracene-type epoxy resin, bisphenol A-type epoxy resin, bisphenol AF-type epoxy resin, and tetraphenylethane-type epoxy resin, with bixylenol-type epoxy resin and biphenyl-type epoxy resin being more preferred.

[0047] Specific examples of solid epoxy resins include DIC's "HP4032H" (naphthalene-type epoxy resin), "HP-4700", "HP-4710" (naphthalene-type tetrafunctional epoxy resin), "N-690" (cresol novolac-type epoxy resin), "N-695" (cresol novolac-type epoxy resin), "HP-7200", "HP-7200HH", and "HP-7200H" (dicyclopentadiene-type epoxy resin). (Fats), "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000", "HP6000L" (naphthylene ether type epoxy resin); Nippon Kayaku Co., Ltd.'s "EPPN-502H" (trisphenol type epoxy resin), "NC7000L" (naphthol novolac type epoxy resin), "NC3000H", "NC3000", "NC3000L", Examples include "NC3100" (biphenyl-type epoxy resin); "ESN475V" (naphthalene-type epoxy resin) and "ESN485" (naphthol novolac-type epoxy resin) from Nippon Steel Chemical & Material Co., Ltd.; "YX4000H" and "YL6121" (biphenyl-type epoxy resin), "YX4000HK" (bixylenol-type epoxy resin), and "YX8800" (anthracene-type epoxy resin) from Mitsubishi Chemical Corporation; "PG-100" and "CG-500" from Osaka Gas Chemical Co., Ltd.; "YL7760" (bisphenol AF-type epoxy resin), "YL7800" (fluorene-type epoxy resin), "jER1010" (solid bisphenol A-type epoxy resin), and "jER1031S" (tetraphenylethane-type epoxy resin) from Mitsubishi Chemical Corporation; and "WHR-991S" (phenolphthaleimidine-type epoxy resin) from Nippon Kayaku Co., Ltd. These may be used individually or in combination of two or more types.

[0048] (b-1) When a liquid epoxy resin and a solid epoxy resin are used in combination as components, their mass ratio (liquid epoxy resin:solid epoxy resin) is preferably 1:0.1 to 1:20, more preferably 1:0.15 to 1:10, and particularly preferably 1:0.2 to 1:5. By having the mass ratio of the liquid epoxy resin and the solid epoxy resin within this range, the desired effects of the present invention can be remarkably obtained.

[0049] The epoxy equivalent of component (b-1) is preferably 50 g / eq. to 5000 g / eq., more preferably 50 g / eq. to 3000 g / eq., even more preferably 80 g / eq. to 2000 g / eq., and even more preferably 110 g / eq. to 1000 g / eq. This range ensures that the crosslinking density of the cured resin composition layer is sufficient to produce a cured product. The epoxy equivalent is the mass of epoxy resin containing one equivalent of epoxy groups. This epoxy equivalent can be measured according to JIS K7236.

[0050] The weight-average molecular weight (Mw) of component (b-1) is preferably 100 to 5000, more preferably 150 to 3000, and even more preferably 200 to 1500. The weight-average molecular weight of the epoxy resin is the weight-average molecular weight on a polystyrene basis, measured by gel permeation chromatography (GPC).

[0051] The content of component (b-1) may be 0% by mass, preferably 2% by mass or more, more preferably 3% by mass or more, and even more preferably 4% by mass or more, when the nonvolatile components in the resin composition layer are taken as 100% by mass. The upper limit is preferably 35% by mass or less, more preferably 32% by mass or less, and even more preferably 30% by mass or less.

[0052] The content of component (b-1) may be 0% by mass when the total resin component in the resin composition layer is considered to be 100% by mass, preferably 3% by mass or more, more preferably 4% by mass or more, and even more preferably 5% by mass or more. The upper limit is preferably 80% by mass or less, more preferably 75% by mass or less, and even more preferably 70% by mass or less.

[0053] --(b-2) Curing Agent -- The (b-2) curing agent as component (b) may have the function of curing the resin composition by reacting with the (b-1) epoxy resin. Examples of curing agents include activated ester resins, phenolic resins, carbodiimide resins, cyanate resins, acid anhydride resins, amine resins, benzoxazine resins, and thiol resins. Among these, the (b-2) curing agent preferably contains activated ester resins and phenolic resins, and more preferably contains phenolic resins. The (b-2) curing agent may be used alone or in combination of two or more types.

[0054] As the active ester resin, compounds having two or more highly reactive ester groups in one molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds, are generally preferred. In addition, the active ester resin may also have an allyl group in addition to the highly reactive ester group. The active ester resin can react with the epoxy resin when combined with an epoxy resin to cure the resin composition, and is therefore sometimes called an "active ester curing agent." The active ester resin is preferably obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. Particularly from the viewpoint of obtaining the effects of the present invention significantly, an active ester resin obtained from a carboxylic acid compound and a hydroxy compound is preferred, and an active ester resin obtained from a carboxylic acid compound and / or a naphthol compound is more preferred. Examples of carboxylic acid compounds include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of phenol compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalein, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadiene-type diphenol compounds, and phenol novolac. Here, "dicyclopentadiene-type diphenol compounds" refers to diphenol compounds obtained by the condensation of two phenol molecules with one dicyclopentadiene molecule.

[0055] Specifically, preferred active ester resins include dicyclopentadiene-type active ester resins, naphthalene-type active ester resins containing a naphthalene structure, active ester resins containing an acetylated phenol novolac, and active ester resins containing a benzoylated phenol novolac. More preferably, the active ester resin is at least one selected from dicyclopentadiene-type active ester resins and naphthalene-type active ester resins, with naphthalene-type active ester resins being even more preferred. As for dicyclopentadiene-type active ester resins, active ester resins containing a dicyclopentadiene-type diphenol structure are preferred.

[0056] Commercially available active ester resins include, for example, "EXB9451," "EXB9460," "EXB9460S," "HPC-8000L-65TM," "HPC-8000-65T," "EXB-8000H," and "EXB-8000L-65TM" (manufactured by DIC Corporation) as active ester curing agents containing a naphthalene structure, such as "EXB-9416-70BK," "EXB-8100L-65T," "HPC-8150-62T," "EXB-8150L-65T," "EXB-8100L-65T," and "EXB-8" (manufactured by DIC Corporation). Examples of phosphorus-containing active ester curing agents include "EXB9401" (manufactured by DIC Corporation); "DC808" (manufactured by Mitsubishi Chemical Corporation) as an active ester curing agent containing an acetylated phenol novolac; "YLH1026", "YLH1030", "YLH1048" (manufactured by Mitsubishi Chemical Corporation), and "EXB-8500-65T" (manufactured by DIC Corporation) as active ester curing agents containing a styryl group and a naphthalene structure include "PC1300-02-65T" and "PC1300-02-65MA" (manufactured by Air Water Corporation).

[0057] The active ester group equivalent of the active ester resin is preferably 50 g / eq. to 3000 g / eq., more preferably 100 g / eq. to 1000 g / eq., even more preferably 100 g / eq. to 500 g / eq., and particularly preferably 100 g / eq. to 300 g / eq. The active ester group equivalent represents the mass of the resin per equivalent of one active ester group.

[0058] In one example, the range of the weight-average molecular weight (Mw) of the active ester resin may be the same as the range of the weight-average molecular weight (Mw) of the epoxy resin (B-1).

[0059] As the phenolic resin, a compound having one or more, preferably two or more, hydroxyl groups bonded to aromatic rings such as benzene rings and naphthalene rings per molecule can be used. When combined with an epoxy resin, the phenolic resin can react with the epoxy resin to cure the resin composition, and is therefore sometimes called a "phenolic curing agent." From the viewpoint of significantly obtaining the effects of the present invention, a phenolic resin having a novolac structure is preferred. Furthermore, from the viewpoint of adhesion, a nitrogen-containing phenolic resin is preferred, and a triazine skeleton-containing phenolic resin is more preferred. Among these, from the viewpoint of significantly obtaining the effects of the present invention, a triazine skeleton-containing phenol novolac resin is preferred. Specific examples of phenolic resins include, for example, "MEH-7700," "MEH-7810," and "MEH-7851" from Meiwa Kasei Co., Ltd., "NHN," "CBN," and "GPH" from Nippon Kayaku Co., Ltd., "SN-170," "SN-180," "SN-190," "SN-475," "SN-485," "SN-495," "SN-375," and "SN-395" from Nippon Steel Chemical & Material Co., Ltd., and "LA-7052," "LA-7054," "LA-3018," "LA-3018-50P," "LA-1356," "TD2090," "TD-2090-60M," and "KA-1163" from DIC Corporation.

[0060] As the carbodiimide resin, a compound having one or more, preferably two or more, carbodiimide structures in one molecule and lacking radical polymerizable groups can be used. Carbodiimide resins can react with epoxy resins when combined with them to cure the resin composition, and are therefore sometimes referred to as "carbodiimide-based curing agents."

[0061] Specific examples of carbodiimide resins include aliphatic biscarbodiimides such as tetramethylene-bis(t-butylcarbodiimide) and cyclohexanebis(methylene-t-butylcarbodiimide); biscarbodiimides such as aromatic biscarbodiimides such as phenylene-bis(xylylcarbodiimide); aliphatic polycarbodiimides such as polyhexamethylenecarbodiimide, polytrimethylhexamethylenecarbodiimide, polycyclohexylenecarbodiimide, poly(methylenebiscyclohexylenecarbodiimide), and poly(isophoronecarbodiimide); and poly(phenylenecarbodiimide), poly(na Examples of polycarbodiimides include aromatic polycarbodiimides such as phthalenecarbodiimide, poly(tylenecarbodiimide), poly(methyldiisopropylphenylenecarbodiimide), poly(triethylphenylenecarbodiimide), poly(diethylphenylenecarbodiimide), poly(triisopropylphenylenecarbodiimide), poly(diisopropylphenylenecarbodiimide), poly(xylylenecarbodiimide), poly(tetramethylxylylenecarbodiimide), poly(methylenediphenylenecarbodiimide), and poly[methylenebis(methylphenylene)carbodiimide].

[0062] Examples of commercially available carbodiimide resins include "Carbodilite V-02B," "Carbodilite V-03," "Carbodilite V-04K," "Carbodilite V-07," and "Carbodilite V-09" from Nisshinbo Chemical Co., Ltd., and "Stabaxol P," "Stabaxol P100," "Stabaxol P400," and "Hycazil 510" from Lanxess Corporation.

[0063] As the cyanate resin, a compound having one or more, preferably two or more cyanate groups in one molecule can be used. When combined with an epoxy resin, the cyanate resin can react with the epoxy resin to cure the resin composition, and is therefore sometimes called a "cyanate-based curing agent." Examples of cyanate resins include bifunctional cyanate resins such as bisphenol A dicyanate, polyphenol cyanate (oligo(3-methylene-1,5-phenylene cyanate)), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanatephenyl) thioether, and bis(4-cyanatephenyl) ether; polyfunctional cyanate resins derived from phenol novolacs and cresol novolacs; and prepolymers in which these cyanate resins are partially triazined. Specific examples of cyanate resins include "PT30" and "PT60" (both phenol novolac type polyfunctional cyanate resins) manufactured by arxada, "BA230" and "BA230S75" (prepolymers in which part or all of bisphenol A dicyanate is triazined to form trimers).

[0064] As the acid anhydride resin, a compound having one or more, preferably two or more, acid anhydride groups in one molecule can be used. When combined with epoxy groups, the acid anhydride resin can react with the epoxy resin to cure the resin composition, and is therefore sometimes called an "acid anhydride curing agent." Specific examples of acid anhydride resins include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexen-1,2-dicarboxylic acid anhydride, trimellitic anhydride, pyromellitic anhydride, and bensophenone tetracarboxylic acid dihydroanhydride. Examples include water-based acid anhydrides, biphenyltetracarboxylic acid dianhydride, naphthalenetetracarboxylic acid dianhydride, oxydiphthalic acid dianhydride, 3,3'-4,4'-diphenylsulfontetracarboxylic acid dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-C]furan-1,3-dione, ethylene glycol bis(anhydrotrimellitate), and polymer-type acid anhydrides such as styrene-maleic acid resin obtained by copolymerizing styrene and maleic acid. Examples of commercially available acid anhydride resins include "HNA-100," "MH-700," "MTA-15," "DDSA," and "OSA" from Shin Nippon Rika Co., Ltd.; "YH-306" and "YH-307" from Mitsubishi Chemical Corporation; "HN-2200" and "HN-5500" from Resona Corporation; and "EF-30," "EF-40," "EF-60," and "EF-80" from Clay Valley Corporation.

[0065] As the amine resin, a compound having one or more, preferably two or more, amino groups in one molecule can be used. When combined with epoxy groups, the amine resin can react with the epoxy resin to cure the resin composition, and is therefore sometimes called an "amine-based curing agent." Examples of amine resins include aliphatic amines, polyetheramines, alicyclic amines, and aromatic amines, with aromatic amines being preferred. The amine resin is preferably a primary amine or a secondary amine, with primary amines being more preferred. Specific examples of amine resins include 4,4'-methylenebis(2,6-dimethylaniline), 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, m-phenylenediamine, m-xylylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, and 2,2-bis(3-amino-4-hydroxyphenyl)propyl Examples include pan, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethanediamine, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis(4-(4-aminophenoxy)phenyl)sulfone, bis(4-(3-aminophenoxy)phenyl)sulfone, etc. Examples of commercially available amine resins include "SEIKACURE-S" from Seika Corporation; "KAYABOND C-200S," "KAYABOND C-100," "Kayahard A-A," "Kayahard A-B," and "Kayahard A-S" from Nippon Kayaku Co., Ltd.; "Epicure W" from Mitsubishi Chemical Corporation; and "DTDA" from Sumitomo Seika Co., Ltd.

[0066] Benzooxazine resins can react with epoxy resins when combined with them to cure the resin composition, and are therefore sometimes referred to as "benzooxazine-based curing agents." Specific examples of benzooxazine resins include "JBZ-OP100D" and "ODA-BOZ" from JFE Chemical Corporation; "HFB2006M" from Showa Polymer Co., Ltd.; and "P-d" and "F-a" from Shikoku Chemicals Co., Ltd.

[0067] Thiol resins can react with epoxy resins when combined with them to cure the resin composition, and are therefore sometimes called "thiol-based curing agents." Examples of thiol resins include trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), and tris(3-mercaptopropyl) isocyanurate.

[0068] (b-2) The active group equivalent of the curing agent is preferably 50 g / eq. to 3000 g / eq., more preferably 100 g / eq. to 1000 g / eq., even more preferably 100 g / eq. to 500 g / eq., and particularly preferably 100 g / eq. to 300 g / eq. The active group equivalent is the mass of the curing agent per equivalent of one active group.

[0069] (b-2) The weight-average molecular weight (Mw) of the curing agent is preferably 100 to 5,000, more preferably 250 to 3,000, and even more preferably 400 to 1,500. The weight-average molecular weight of the resin can be measured as a polystyrene equivalent by gel permeation chromatography (GPC).

[0070] The equivalent ratio of (b-1) epoxy resin to (b-2) curing agent ([total number of active groups in (b-2) curing agent] / [total number of epoxy groups in (b-1) epoxy resin]) is preferably 0.1 or more, more preferably 0.2 or more, even more preferably 0.3 or more, preferably 3 or less, more preferably 2.5 or less, and particularly preferably 2 or less. The "total number of active groups in the curing agent" refers to the sum of all values ​​obtained by dividing the mass of the nonvolatile components of the curing agent present in the resin composition layer by the equivalent number of active groups.

[0071] (b-2) The curing agent content is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 3% by mass or more, preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, when the nonvolatile components in the resin composition layer are taken as 100% by mass.

[0072] (b-2) The curing agent content may be 0% by mass when the resin component in the resin composition layer is considered to be 100% by mass, preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, preferably 40% by mass or less, more preferably 35% by mass or less, and even more preferably 30% by mass or less.

[0073] (b) The content of the thermosetting resin is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 20% by mass or more, preferably 55% by mass or less, more preferably 50% by mass or less, and even more preferably 45% by mass or less, when the nonvolatile components in the resin composition layer are taken as 100% by mass.

[0074] (b) The content of the thermosetting resin may be 0% by mass when the total resin component in the resin composition layer is 100% by mass, preferably 65% ​​by mass or more, more preferably 70% by mass or more, even more preferably 75% by mass or more, preferably 94% by mass or less, more preferably 90% by mass or less, and even more preferably 86% by mass or less.

[0075] - (c) Thermoplastic resin - The resin composition layer may contain (c) thermoplastic resin as component (c). This (c) thermoplastic resin as component (c) does not include those corresponding to components (a) to (b) described above. Component (c) may be used alone or in combination of two or more types.

[0076] (c) Examples of thermoplastic resins include phenoxy resin, polyvinyl acetal resin, polyolefin resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polyphenylene ether resin, polyetheretherketone resin, polyester resin, and the like.

[0077] (c) The weight-average molecular weight of the thermoplastic resin in terms of polystyrene is preferably 10,000 or more, more preferably 15,000 or more, even more preferably 18,000 or more, or 40,000 or more. The upper limit is preferably 100,000 or less, more preferably 70,000 or less, and even more preferably 60,000 or less. (c) The weight-average molecular weight of the thermoplastic resin in terms of polystyrene is measured by gel permeation chromatography (GPC). Specifically, (c) the weight-average molecular weight of the thermoplastic resin in terms of polystyrene can be calculated using a calibration curve of standard polystyrene, with a Shimadzu LC-9A / RID-6A measuring device, a Showa Denko Shodex K-800P / K-804L / K-804L column, and chloroform or the like as the mobile phase, measured at a column temperature of 40°C.

[0078] Examples of phenoxy resins include phenoxy resins having one or more skeletons selected from the group consisting of bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenolacetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, terpene skeleton, and trimethylcyclohexane skeleton. The ends of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. Phenoxy resins may be used alone or in combination of two or more types. Specific examples of phenoxy resins include "1256" and "4250" (both phenoxy resins containing a bisphenol A skeleton), "YX8100" (phenoxy resin containing a bisphenol S skeleton), "YX7800BH40" (phenoxy resin containing a fluorene skeleton), and "YX6954" (phenoxy resin containing a bisphenol acetophenone skeleton), all manufactured by Mitsubishi Chemical Corporation. Other examples include "FX280" and "FX293" from Nippon Steel Chemical & Material Corporation, and "YL7500BH30", "YX6954BH30", "YX7553", "YX7553BH30", "YL7553BH30", "YL7769BH30", "YL6794", "YL7213", "YL7290", and "YL7482" from Mitsubishi Chemical Corporation.

[0079] Examples of polyvinyl acetal resins include polyvinyl formal resin and polyvinyl butyral resin, with polyvinyl butyral resin being preferred. Specific examples of polyvinyl acetal resins include, for example, the S-Rec BH series, BX series (e.g., BX-5Z), KS series (e.g., KS-1), BL series, and BM series manufactured by Sekisui Chemical Co., Ltd.

[0080] Specific examples of polyimide resins include "Ricacoat SN20" and "Ricacoat PN20" manufactured by Shin Nippon Rika Co., Ltd. Other specific examples of polyimide resins include linear polyimides obtained by reacting a bifunctional hydroxyl-terminated polybutadiene, a diisocyanate compound, and a tetrabasic acid anhydride (polyimides described in Japanese Patent Publication No. 2006-37083), and modified polyimides containing a polysiloxane skeleton (polyimides described in Japanese Patent Publication No. 2002-12667 and Japanese Patent Publication No. 2000-319386, etc.).

[0081] Specific examples of polyamide-imide resins include "Viromax HR11NN" and "Viromax HR16NN" manufactured by Toyobo Co., Ltd. Other specific examples of polyamide-imide resins include modified polyamide-imides such as "KS9100" and "KS9300" (polysiloxane skeleton-containing polyamide-imide) manufactured by Resonaq Corporation.

[0082] Specific examples of polyethersulfone resins include "PES5003P" manufactured by Sumitomo Chemical Co., Ltd. Specific examples of polyphenylene ether resins include "OPE-2St 1200," an oligophenylene ether styrene resin manufactured by Mitsubishi Gas Chemical Company. Specific examples of polyetheretherketone resins include "Sumiproi K" manufactured by Sumitomo Chemical Co., Ltd. Specific examples of polyetherimide resins include "Ultem" manufactured by GE Inc.

[0083] Specific examples of polysulfone resins include Solvay Advanced Polymers' polysulfones "P1700" and "P3500".

[0084] Examples of polyolefin resins include ethylene-based copolymer resins such as low-density polyethylene, ultra-low-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-methyl acrylate copolymer; and polyolefin-based elastomers such as polypropylene and ethylene-propylene block copolymer.

[0085] Examples of polyester resins include polyethylene terephthalate resin, polyethylene naphthalate resin, polybutylene terephthalate resin, polybutylene naphthalate resin, polytrimethylene terephthalate resin, polytrimethylene naphthalate resin, and polycyclohexanedimethyl terephthalate resin.

[0086] (c) Phenoxy resin is preferred as the thermoplastic resin. In particular, phenoxy resin with a weight-average molecular weight of 40,000 or more is preferred as the thermoplastic resin (c).

[0087] (c) The content of thermoplastic resin may be 0% by mass, preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.6% by mass or more, when the nonvolatile components in the resin composition layer are taken as 100% by mass. The upper limit is preferably 15% by mass or less, more preferably 10% by mass or less, even more preferably 8% by mass or less, or 5% by mass or less.

[0088] (c) The thermoplastic resin content is preferably 0.2% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1.0% by mass or more, when the resin components in the resin composition layer are considered to be 100% by mass. The upper limit is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less.

[0089] - (d) Curing accelerator - The resin composition layer may contain a curing accelerator as component (d). The curing accelerator as component (d) does not include those corresponding to components (a) to (c) described above. The curing accelerator (d) can act as a catalyst in the reaction of the epoxy resin (b-1) to accelerate the curing of the resin composition layer.

[0090] (d) Examples of curing accelerators include phosphorus-based curing accelerators, urea-based curing accelerators, guanidine-based curing accelerators, imidazole-based curing accelerators, metal-based curing accelerators, amine-based curing accelerators, etc., with amine-based curing accelerators being preferred. (d) One type of curing accelerator may be used alone, or two or more types may be used in combination.

[0091] Examples of phosphorus-based curing accelerators include aliphatic phosphonium salts such as tetrabutylphosphonium bromide, tetrabutylphosphonium chloride, tetrabutylphosphonium acetate, tetrabutylphosphonium decanoate, tetrabutylphosphonium laurate, bis(tetrabutylphosphonium) pyromelitate, tetrabutylphosphonium hydrogen hexahydrophthalate, tetrabutylphosphonium 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenolate, di-tert-butyldimethylphosphonium tetraphenylborate; methyltriphenylphosphonium bromide, ethyltriphenylphosphonium bromide, propyltriphenylphosphonium bromide, butyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, tetraphenylphosphonium bromide, p-tolyltriphenylphosphonium tetra-p-tolylborate, tetraphenylphosphonium bromide, and tetraphenylphosphonium bromide. Aromatic phosphonium salts such as tetraphenylborate, tetraphenylphosphonium tetra-p-tolylborate, triphenylethylphosphonium tetraphenylborate, tris(3-methylphenyl)ethylphosphonium tetraphenylborate, tris(2-methoxyphenyl)ethylphosphonium tetraphenylborate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, and butyltriphenylphosphonium thiocyanate; aromatic phosphine-borane complexes such as triphenylphosphine and triphenylborane; aromatic phosphine-quinone addition products such as triphenylphosphine-p-benzoquinone addition products; aliphatic phosphines such as tributylphosphine, tri-tert-butylphosphine, trioctylphosphine, di-tert-butyl(2-butenyl)phosphine, di-tert-butyl(3-methyl-2-butenyl)phosphine, and tricyclohexylphosphine;Dibutylphenylphosphine, di-tert-butylphenylphosphine, methyldiphenylphosphine, ethyldiphenylphosphine, butyldiphenylphosphine, diphenylcyclohexylphosphine, triphenylphosphine, tri-o-tolylphosphine, tri-m-tolylphosphine, tri-p-tolylphosphine, tris(4-ethylphenyl)phosphine, tris(4-propylphenyl)phosphine, tris(4-isopropylphenyl)phosphine, tris(4-butylphenyl)phosphine, tris(4-tert-butylphenyl)phosphine, tris(2,4-dimethylphenyl)phosphine, tris(2,5-dimethylphenyl)phosphine, tris(2,6-dimethylphenyl)phosphine Examples include aromatic phosphines such as tris(3,5-dimethylphenyl)phosphine, tris(2,4,6-trimethylphenyl)phosphine, tris(2,6-dimethyl-4-ethoxyphenyl)phosphine, tris(2-methoxyphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(4-ethoxyphenyl)phosphine, tris(4-tert-butoxyphenyl)phosphine, diphenyl-2-pyridylphosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,2-bis(diphenylphosphino)acetylene, and 2,2'-bis(diphenylphosphino)diphenyl ether.

[0092] Examples of urea-based curing accelerators include aliphatic dimethylureas such as 1,1-dimethylurea, 1,1,3-trimethylurea, 3-ethyl-1,1-dimethylurea, 3-cyclohexyl-1,1-dimethylurea, and 3-cyclooctyl-1,1-dimethylurea; 3-phenyl-1,1-dimethylurea, 3-(4-chlorophenyl)-1,1-dimethylurea, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, 3-(3-chloro-4-methylphenyl)-1,1-dimethylurea, 3-(2-methylphenyl)-1,1-dimethylurea, 3-(4-methylphenyl)-1,1-dimethylurea, and 3-(3,4-dimethylphenyl)-1,1-dimethylurea. Examples include aromatic dimethylureas such as thylurea, 3-(4-isopropylphenyl)-1,1-dimethylurea, 3-(4-methoxyphenyl)-1,1-dimethylurea, 3-(4-nitrophenyl)-1,1-dimethylurea, 3-[4-(4-methoxyphenoxy)phenyl]-1,1-dimethylurea, 3-[4-(4-chlorophenoxy)phenyl]-1,1-dimethylurea, 3-[3-(trifluoromethyl)phenyl]-1,1-dimethylurea, N,N-(1,4-phenylene)bis(N',N'-dimethylurea), and N,N-(4-methyl-1,3-phenylene)bis(N',N'-dimethylurea) [toluenebisdimethylurea].

[0093] Examples of guanidine-based curing accelerators include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]deca-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]deca-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, and 1-(o-tolyl)biguanide.

[0094] Examples of imidazole-based curing accelerators include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2- Phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-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 isocyanurate adduct, 2-phenylimidazole isocyanurate adduct Examples include imidazole compounds such as 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline, as well as adducts of imidazole compounds with epoxy resins. Examples of commercially available imidazole-based curing accelerators include "1B2PZ", "2E4MZ", "2MZA-PW", "2MZ-OK", "2MA-OK", "2MA-OK-PW", "2PHZ", "2PHZ-PW", "Cl1Z", "Cl1Z-CN", "Cl1Z-CNS", and "C11Z-A" from Shikoku Chemicals Corporation; and "P200-H50" from Mitsubishi Chemical Corporation.

[0095] Examples of metal-based hardening accelerators include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of organometallic complexes include organocobalt complexes such as cobalt(II) acetylacetonate and cobalt(III) acetylacetonate, organocopper complexes such as copper(II) acetylacetonate, organozinc complexes such as zinc(II) acetylacetonate, organoiron complexes such as iron(III) acetylacetonate, organonickel complexes such as nickel(II) acetylacetonate, and organomanganese complexes such as manganese(II) acetylacetonate. Examples of organometallic salts include zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

[0096] Examples of amine-based curing accelerators include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene. Commercially available amine-based curing accelerators may also be used, such as "MY-25" manufactured by Ajinomoto Fine Techno Co., Ltd.

[0097] (d) The content of the curing accelerator is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, even more preferably 0.03% by mass or more, preferably 3% by mass or less, more preferably 1% by mass or less, and even more preferably 0.5% by mass or less, based on 100% by mass of the nonvolatile components in the resin composition layer.

[0098] (d) The content of the curing accelerator is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, preferably 3% by mass or less, more preferably 1.5% by mass or less, and even more preferably 1% by mass or less, based on 100% by mass of the resin components in the resin composition layer.

[0099] - (e) Organic Filler - The resin composition layer may contain (e) organic filler as component (e). This (e) organic filler as component (e) does not include components (a) to (d) described above. The (e) organic filler is usually immiscible with resin components other than the (e) organic filler and is included in the resin composition in granular form, and is included in the cured product while maintaining that granular form. Furthermore, one type of (e) organic filler may be used alone, or two or more types may be used in combination.

[0100] (e) As the organic filler, particles of organic material may be used. (e) As the organic material contained in the organic filler, rubber components are preferred. Examples of rubber components include silicone elastomers such as polydimethylsiloxane; olefin-based thermoplastic elastomers such as polybutadiene, polyisoprene, polychlorobutadiene, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-isobutylene copolymer, acrylonitrile-butadiene copolymer, isoprene-isobutylene copolymer, isobutylene-butadiene copolymer, ethylene-propylene-diene terpolymer, ethylene-propylene-butene terpolymer; and thermoplastic elastomers such as acrylic-based thermoplastic elastomers such as poly(meth)acrylate propyl, poly(meth)acrylate butyl, poly(meth)acrylate cyclohexyl, and poly(meth)acrylate octyl. Furthermore, silicone-based rubbers such as polyorganosiloxane rubber may be mixed with the rubber component. The rubber components contained in the rubber particles have a glass transition temperature of, for example, 0°C or lower, preferably -10°C or lower, more preferably -20°C or lower, and even more preferably -30°C or lower.

[0101] (e) The organic filler may be a core-shell type rubber particle consisting of core particles containing the rubber components listed above and a shell portion formed by graft copolymerization of monomer components copolymerizable with the rubber components contained in the core particles. Here, "core-shell type" does not necessarily refer only to those in which the core particles and the shell portion can be clearly distinguished, but also includes those in which the boundary between the core particles and the shell portion is unclear, and the core particles do not have to be completely covered by the shell portion.

[0102] (e) Specific examples of organic fillers include, for example, "CHT" from Samsung SDI; "B602" from Techno UMG; "Paraloid EXL-2602", "Paraloid EXL-2603", "Paraloid EXL-2655", "Paraloid EXL-2311", "Paraloid EXL-2313", "Paraloid EXL-2315", "Paraloid KM-330", "Paraloid KM-336P", "Paraloid KCZ-201" from Dow Corporation; and "Metablen C-223A", "Metablen E- Examples include "901", "Metablen S-2001", "Metablen W-450A", "Metablen SRK-200", Kaneka Corporation's "Kaneace M-511", "Kaneace M-600", "Kaneace M-400", "Kaneace M-580", "Kaneace MR-01", and Aica Industries Corporation's "Stafiloid AC3355", "Stafiloid AC3816", "Stafiloid AC3816N", "Stafiloid AC3832", "Stafiloid AC4030", and "Stafiloid AC3364".

[0103] (e) The content of the organic filler is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, even more preferably 0.3% by mass or more, preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 5% by mass or less, when the nonvolatile components in the resin composition layer are taken as 100% by mass.

[0104] (e) The content of the organic filler is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, even more preferably 0.5% by mass or more, preferably 15% by mass or less, more preferably 13% by mass or less, and even more preferably 10% by mass or less, when the resin component in the resin composition layer is considered to be 100% by mass.

[0105] <(f) Flame retardant> The resin composition layer may contain (f) a flame retardant as component (f). This (f) flame retardant as component (f) does not include those corresponding to components (a) to (e) described above. Component (f) may be used alone or in combination of two or more types.

[0106] (f) Examples of flame retardants include phosphazene compounds, organophosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicone flame retardants, and metal hydroxides.

[0107] The phosphazene compound is not particularly limited as long as it is a cyclic compound with nitrogen and phosphorus as constituent elements.

[0108] Specific examples of phosphazene compounds include, for example, "SPH-100," "SPS-100," "SPB-100," and "SPE-100" manufactured by Otsuka Chemical Co., Ltd., and "FP-100," "FP-110," "FP-300," and "FP-400" manufactured by Fushimi Pharmaceutical Co., Ltd., with "SPH-100" manufactured by Otsuka Chemical Co., Ltd. being preferred.

[0109] As a flame retardant other than a phosphazene compound, commercially available products may be used, such as "HCA-HQ" manufactured by Sanko Co., Ltd. and "PX-200" manufactured by Daihachi Chemical Industry Co., Ltd. As a flame retardant, one that is not easily hydrolyzed is preferred, such as 10-(2,5-dihydroxyphenyl)-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide.

[0110] (f) The flame retardant content is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, even more preferably 0.5% by mass or more, preferably 15% by mass or less, more preferably 12% by mass or less, and even more preferably 10% by mass or less, when the nonvolatile components in the resin composition layer are taken as 100% by mass.

[0111] (f) The flame retardant content is preferably 0.2% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.8% by mass or more, when the resin component in the resin composition layer is considered to be 100% by mass. The upper limit is preferably 24% by mass or less, more preferably 18% by mass or less, and even more preferably 15% by mass or less.

[0112] <(g) Optional Additives> The resin composition layer may further contain (g) optional additives. (g) Optional additives as components (g) do not include those corresponding to components (a) to (f) described above. (g) Optional additives include: radical polymerizable compounds; organometallic compounds such as organocopper compounds, organozinc compounds, and organocobalt compounds; colorants such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium dioxide, and carbon black; polymerization inhibitors such as hydroquinone, catechol, pyrogallol, and phenothiazine; leveling agents such as silicone-based leveling agents and acrylic polymer-based leveling agents; thickeners such as bentonite and montmorillonite; defoaming agents such as silicone-based defoaming agents, acrylic-based defoaming agents, fluorine-based defoaming agents, and vinyl resin-based defoaming agents; and ultraviolet absorbers such as benzotriazole-based ultraviolet absorbers. Examples of additives include: adhesion improvers such as urea silane; adhesion improvers such as triazole-based adhesion improvers, tetrazole-based adhesion improvers, and triazine-based adhesion improvers; antioxidants such as hindered phenol-based antioxidants; fluorescent whitening agents such as stilbene derivatives; surfactants such as fluorine-based surfactants and silicone-based surfactants; dispersants such as phosphate ester-based dispersants, polyoxyalkylene-based dispersants, acetylene-based dispersants, silicone-based dispersants, anionic dispersants, and cationic dispersants; and stabilizers such as borate-based stabilizers, titanate-based stabilizers, aluminate-based stabilizers, zirconate-based stabilizers, isocyanate-based stabilizers, carboxylic acid-based stabilizers, and carboxylic acid anhydride-based stabilizers. (g) Any additive may be used alone or in combination of two or more types.

[0113] <(h) Solvent> The resin composition may also contain (h) solvent as an optional volatile component in combination with the non-volatile components such as components (a) to (g) described above. Typically, an organic solvent is used as the (h) solvent. Examples of organic solvents include: ketone solvents such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, and cyclohexanone; ester solvents such as methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, isoamyl acetate, methyl propionate, ethyl propionate, and γ-butyrolactone; ether solvents such as tetrahydropyran, tetrahydrofuran, 1,4-dioxane, diethyl ether, diisopropyl ether, dibutyl ether, diphenyl ether, and anisole; alcohol solvents such as methanol, ethanol, propanol, butanol, and ethylene glycol; 2-ethoxyethyl acetate, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl diglycol acetate, γ-butyrolactone, and methoxypropionate. Examples include ether ester solvents such as methyl acid; ester alcohol solvents such as methyl lactate, ethyl lactate, and methyl 2-hydroxyisobutyrate; ether alcohol solvents such as 2-methoxypropanol, 2-methoxyethanol, 2-ethoxyethanol, propylene glycol monomethyl ether, and diethylene glycol monobutyl ether (butyl carbitol); amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone; sulfoxide solvents such as dimethyl sulfoxide; nitrile solvents such as acetonitrile and propionitrile; aliphatic hydrocarbon solvents such as hexane, cyclopentane, cyclohexane, and methylcyclohexane; and aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene, and trimethylbenzene. (h) A single solvent may be used alone, or two or more may be used in combination.

[0114] <<Optional Layers>> The resin sheet with support may further include any additional layers in combination with the support and the resin composition layer, as needed. Examples of optional layers include a protective film provided on the side of the resin composition layer that is not bonded to the support (i.e., the side opposite to the support). The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. When a protective film is provided, the adhesion of dust and scratches to the surface of the resin composition layer can be suppressed.

[0115] (Method for manufacturing a resin sheet with a support) A resin sheet with a support can be manufactured, for example, by a method that includes forming a resin composition layer on a support. One embodiment of the method for manufacturing a resin sheet with a support includes, in this order, the steps of: preparing a resin varnish containing components that constitute the resin composition layer; applying the resin varnish onto the support; and drying the applied resin varnish to form a resin composition layer.

[0116] Resin varnish may be manufactured by mixing components and solvents that may be included in the resin composition layer. As the solvent for the resin varnish, the solvent (h) described above may be used. Each component may be mixed partially or entirely at the same time, or sequentially. The temperature may be set appropriately during the mixing of each component, and thus heating and / or cooling may be performed temporarily or throughout the process. Furthermore, stirring or shaking may be performed during the mixing of each component.

[0117] The resin varnish can be applied using a coating device such as a die coater. The drying conditions after applying the resin varnish are not particularly limited, but the drying is carried out so that the solvent content in the resin composition layer is usually 10% by mass or less, preferably 5% by mass or less. Drying can be carried out by drying methods such as heating or blowing hot air, but drying by heating is preferred.

[0118] The drying temperature varies depending on the components contained in the resin composition layer, but is usually around 115°C, preferably 60°C or higher, more preferably 70°C or higher, even more preferably 80°C or higher, or 100°C or higher, preferably 160°C or lower, more preferably 150°C or lower, and even more preferably 140°C or lower.

[0119] The drying time is preferably 1 minute or more, more preferably 1.5 minutes or more, even more preferably 2 minutes or more, preferably 10 minutes or less, more preferably 8 minutes or less, and even more preferably 7 minutes or less.

[0120] The content of (h) solvent in the resin composition layer after drying the resin varnish is preferably 8% by mass or less, more preferably 5% by mass or less, even more preferably 3.5% by mass or less, preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 0.8% by mass or more, based on 100% by mass of the total components of the resin composition layer.

[0121] The resin sheet can be stored by rolling it up. If the resin sheet has a protective film, it can be used after removing the protective film.

[0122] <Process (II)> In process (II), a resin sheet with a support is laminated onto a substrate. The "substrate" that can be used in process (II) is a material that will become a substrate for a printed circuit board, and examples include glass epoxy substrates, metal substrates, polyester substrates, polyimide substrates, BT resin substrates, thermosetting polyphenylene ether substrates, etc. The substrate may also have a conductive layer on one or both sides, and this conductive layer may be patterned. An inner layer substrate in which a conductive layer (circuit) is formed on one or both sides of the substrate is sometimes called an "inner layer circuit board". Intermediate products on which an insulating layer and / or a conductive layer is to be further formed when manufacturing a printed circuit board are also included in the "substrate" as described above. If the printed circuit board is a circuit board with embedded components, an inner layer substrate with embedded components may be used.

[0123] Lamination of a substrate and a resin sheet with a support can be performed, for example, by heating and pressing the resin sheet with the support onto the substrate from the support side. Examples of a member used to heat and press the resin sheet with the support onto the substrate (hereinafter also referred to as the "heat-pressing member") include a heated metal plate (such as a SUS end plate) or a metal roll (such as a SUS roll). It is preferable to press the resin sheet with the support via an elastic material such as heat-resistant rubber, rather than directly pressing the heat-pressing member onto the resin sheet with the support, so that the resin sheet with the support can adequately follow the surface irregularities of the substrate.

[0124] Lamination of the substrate and the resin sheet with support may be carried out by a vacuum lamination method. In the vacuum lamination method, the heat-pressing temperature is preferably in the range of 60°C to 160°C, more preferably in the range of 80°C to 140°C, the heat-pressing pressure is preferably in the range of 0.098 MPa to 1.77 MPa, more preferably in the range of 0.29 MPa to 1.47 MPa, and the heat-pressing time is preferably in the range of 20 seconds to 400 seconds, more preferably in the range of 30 seconds to 300 seconds. Lamination is preferably carried out under reduced pressure conditions of 26.7 hPa or less.

[0125] Lamination can be performed using a commercially available vacuum laminator. Examples of commercially available vacuum laminators include vacuum pressure laminators manufactured by Meiki Seisakusho Co., Ltd., vacuum applicators manufactured by Nikko Materials Co., Ltd., and batch-type vacuum pressure laminators. After lamination, the laminated resin sheet with support may be smoothed by pressing a heat-sealing member from the support side under normal pressure (atmospheric pressure). The pressing conditions for the smoothing process can be the same as the heat-sealing conditions for lamination. The smoothing process can be performed using a commercially available laminator. Lamination and smoothing may be performed continuously using the above-mentioned commercially available vacuum laminator.

[0126] <Process (III)> In process (III), the resin composition layer of the support-attached resin sheet laminated on the substrate is heat-cured to form an insulating layer.

[0127] The specific thermal curing conditions for the resin composition layer may be those commonly used when forming the insulating layer of a circuit board. The thermal curing conditions for the resin composition layer may also vary depending on the type of components contained in the resin composition layer. For example, the curing temperature is preferably 120°C to 240°C, more preferably 140°C to 220°C, and even more preferably 150°C to 210°C. The curing time is preferably 5 minutes to 120 minutes, more preferably 10 minutes to 100 minutes, and even more preferably 15 minutes to 100 minutes.

[0128] Furthermore, when the resin composition layer is heat-cured, the process may include preheating the resin composition layer at a temperature lower than the curing temperature before heat curing. For example, prior to heat curing the resin composition layer, the resin composition layer may be preheated at a temperature of 50°C to 150°C, preferably 60°C to 140°C, more preferably 70°C to 130°C for at least 5 minutes, preferably 5 to 150 minutes, more preferably 15 to 120 minutes, and even more preferably 15 to 100 minutes. Preheating is usually performed after step (II). Also, if a smoothing treatment is performed after lamination of the substrate and the resin sheet with support, preheating may be performed after the smoothing treatment.

[0129] The degree of curing of the insulating layer before the post-processing step (IV) after step (III) is preferably 40% or more, more preferably 45% or more, and even more preferably 50% or more, from the viewpoint of obtaining the desired aperture diameter of the insulating layer. There is no particular upper limit, but it is preferably 100% or less, more preferably 99% or less, and even more preferably 98% or less. By adjusting the thermal curing conditions so that the degree of curing of the insulating layer falls within this range, it becomes easier to form holes with small aperture diameters in the insulating layer. The degree of curing can be determined by the method described in the examples below.

[0130] <Process (IV)> In process (IV), N holes (where N is an integer of 3 or more) are formed in succession in the support and insulating layer using a laser. The details of process (IV) include (IV-1) the process of forming the first hole, which is the first hole to be formed, (IV-2) the process of forming the second hole, which is the second hole to be formed, and (IV-3) the process of forming the nth hole, which is the nth hole to be formed (where n is an integer satisfying 3 ≤ n ≤ N). A specific example of process (IV) is to form the first hole using a laser, followed by the second hole, the third hole, ... the nth hole, ... the nth hole, and S ｎ－１ ≥3r ｎ－１ Relationship and S １ ≥3r １ Form the holes in order to satisfy the relationship (S ｎ－１ represents the distance from the center of the (n-1)th hole to the center of the nth hole, and r ｎ－１ S represents the opening diameter of the insulating layer for the (n-1)th hole. １ represents the distance from the center of the first hole to the center of the second hole, and r １ represents the opening diameter of the insulating layer of the first hole. Therefore, for example, when N = n = 3, the distance from the center of the first hole to the center of the third hole is shorter than the distance from the center of the first hole to the center of the second hole. Also, as shown in Figure 22 as an example, when forming the fourth hole 40, the already formed holes are the first to third holes 10, 20, and 30. Since the hole formed furthest from the center of the first hole 10 is the third hole 30, the distance from the center of the first hole 10 to the center of the third hole 30 is the maximum center-to-center distance S. ｍ This results in the maximum center-to-center distance S. ｍ This refers to the maximum distance between the centers of multiple already formed holes.

[0131] As described above, at least one of the nth holes from the third hole to the nth hole is formed inside a circle whose diameter is the maximum inter-center distance among the already formed multiple holes. The nth hole formed inside the circle is preferably formed at a position where the distance from the center of an already formed hole adjacent to the nth hole to the center of the nth hole (for example, in Figures 5 and 6, the distance from the center of the first hole 10 to the center of the third hole 30; in Figure 22, the distance from the center of the first hole 10 to the center of the fourth hole 40; in Figure 24, the distance from the center of the second hole 20 to the center of the fifth hole 50) is preferably 200 μm or less. Therefore, the number of nth holes formed inside the circle whose diameter is the maximum inter-center distance is not limited as long as they can be formed at a position where the distance is within a predetermined range. The preferred range of the distance is shown in Figure 6, p １ It is the same as above, preferably 200 μm or less, more preferably 180 μm or less, even more preferably 150 μm or less, preferably 10 μm or more, more preferably 20 μm or more, and even more preferably 30 μm or more.

[0132] The proportion of holes formed inside a circle whose diameter is the maximum center-to-center distance is preferably 5% or more, more preferably 10% or more, even more preferably 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more, of the third to the Nth hole. There is no particular upper limit, but it may be 100%, or 100% or less, etc.

[0133] Of the distances between the centers of multiple already formed holes, the maximum distance S between centers is... ｍ When forming a hole inside a circle with a diameter of S, the hole is defined by the maximum distance S between its centers. ｍ The holes can be formed anywhere inside a circle with a diameter of , and the position of the holes can be determined by the shape and area of ​​the circuit board being manufactured. In particular, as shown in Figure 5 as an example, the distance between the centers of the first hole 10 and the second hole 20 (in Figure 5, n=3, so the distance between the centers is the maximum distance S between the centers) can be used. ｍWhen the line is represented as a straight line, it is preferable to form the third hole 30 at a location where the center of the third hole 30 lies on that straight line. That is, it is preferable to form the third hole 30 at a position where the centers of the first hole 10, the second hole 20, and the third hole 30 are in a straight line. Similarly, as shown in Figure 22 as an example, the distance between the centers of the first hole 10 and the third hole 30 is the maximum center distance S. ｍ The maximum distance S between the centers of the first hole 10 and the third hole 30 is... ｍ When the line is represented as a straight line, it is preferable to form the fourth hole 40 at a location where its center lies on that straight line. That is, it is preferable to form the fourth hole 40 at a position where the centers of the first hole 10, the second hole 20, the third hole 30, and the fourth hole 40 are in a straight line. Here, "hole" is a concept that includes via holes and trenches. Step (IV) may be repeated as necessary. The shape of the hole, that is, the shape of the contour of the opening when viewed in the extending direction, is not particularly limited, but is generally circular (approximately circular).

[0134] As mentioned above, the high density of wiring on circuit boards necessitates a reduction in the distance between the centers of the holes.

[0135] Figure 1 is a cross-sectional view showing an example of the state immediately after the insulating layer 2 and support 3 are laminated on the substrate 1 and the first hole 10 is formed on the support 3 and insulating layer 2. As shown in the example in Figure 1, a laser is used to drill holes in the support 3 and insulating layer 2 to form the first hole 10. Immediately after the first hole 10 is formed, the support 31 around the first hole 10 is in a state where it is easy to drill holes with a laser because heat is transferred from the laser irradiation. If a hole (not shown) is to be formed in the area around the first hole 31 adjacent to the first hole 10 in this state, the opening diameter of the hole in the support becomes large, and the opening diameter of the insulating layer also becomes large accordingly. As a result, it is not possible to make the distance between the centers of the holes smaller.

[0136] In this invention, as shown in Figure 2 as an example, in step (IV), a first hole 10 is formed by a laser, and then a second hole 20 is formed in a location 32 where heat from the laser irradiation has not been transmitted. After the second hole 20 is formed, when the heat around the first hole 31 has cooled, the maximum inter-center distance S among the inter-center distances between the multiple already formed holes is determined. ｍ The nth hole (not shown) is formed inside a circle with a diameter of (in the case of n=3, at a position between the first hole 10 and the second hole 20, and adjacent to the first hole 10). This suppresses the enlargement of the opening diameter of the support for the nth hole adjacent to the first hole, and consequently suppresses the enlargement of the opening diameter of the insulating layer, and also improves the machinability of drilling.

[0137] It is preferable to carry out process (IV) in the order of process (IV-1) to (IV-3). Alternatively, in process (IV), other holes may be formed after process (IV-2) has been carried out, and then process (IV) may be carried out again if necessary. Therefore, although process (IV) is a process of continuously forming N holes, this "N holes" does not represent the total number of holes that the manufactured circuit board may have.

[0138] The following describes the first to third embodiments of process (IV) as specific examples, but process (IV) is not limited to these. Furthermore, explanations will be omitted where necessary to avoid repetition in each embodiment.

[0139] The first embodiment of process (IV) is the case where n = 3. In the first embodiment of process (IV), first, in process (IV-1), the first hole 10 is formed by a laser.

[0140] Examples of laser light sources include carbon dioxide lasers (CO2). ２ Lasers, UV-YAG laser, YAG laser, YAG-Green laser, YAG-DUV laser, YVO ４Examples include lasers, YLF lasers, and excimer lasers. Among these, carbon dioxide lasers and UV-YAG lasers are preferred from the viewpoint of forming holes with a narrow distance between the centers of adjacent holes.

[0141] The laser irradiation conditions are preferably set to form a hole with a desired depth and aperture diameter. Furthermore, if the number of shots is two or more, the laser may be irradiated in either burst mode or cycle mode. For example, when irradiating with a carbon dioxide laser, the number of shots is preferably four or fewer, more preferably three or fewer, and even more preferably two or fewer.

[0142] When irradiating with a UV-YAG laser, the number of shots is preferably 100 shots or less, more preferably 90 shots or less, even more preferably 80 shots or less, preferably 10 shots or more, more preferably 15 shots or more, and even more preferably 20 shots or more.

[0143] When there are two or more shots, burst mode, which involves continuous shots, can cause heat buildup within the hole, leading to a tendency for the hole's opening diameter to increase. Therefore, it is also possible to form the hole using cycle mode, which involves multiple shots spaced apart.

[0144] The energy of the laser beam depends on conditions such as the number of shots, the depth of the hole, and the thickness of the support. From the viewpoint of smoothly forming the hole, the energy of the laser beam per shot is preferably set to 0.0001 mJ or more, more preferably 0.0005 mJ or more, and even more preferably 0.001 mJ or more. From the viewpoint of suppressing damage to the insulating layer due to excessive energy, the upper limit of the laser beam energy is preferably 5 mJ or less, more preferably 4 mJ or less, and even more preferably 3.5 mJ or less.

[0145] Hole formation using laser light may be carried out using commercially available laser devices. Examples of commercially available laser devices include the "LU-2L212 / M50L" from Via Mechanics, "LC-2E21B / 1C" from Hitachi Via Mechanics, "LC-K212" from Hitachi, Ltd., "ML605GTWIII" from Mitsubishi Electric Corporation, and the circuit board drilling laser processing machine from Matsushita Welding Systems Corporation.

[0146] The opening diameter of the support for the first hole is preferably 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0147] The target opening diameter of the insulating layer of the first hole is preferably 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0148] The opening diameter r of the insulating layer of the first hole １ Preferably, the particle size is 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, and preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0149] As shown in Figures 3 and 4, an example is created by forming the first hole 10 in step (IV-1), and then forming the second hole 20 in step (IV-2). In detail of step (IV-2), the second hole 20 is formed in a location where the heat from the laser irradiation during the formation of the first hole 10 was not transmitted. The opening diameter of the insulating layer of the first hole 10 is set to r １ Let (μm) be the distance from the center of the first hole 10 to the center of the second hole 20, and S be the distance from the center of the first hole 10 to the center of the second hole 20. １ When (μm), S １ ≥3r １ A laser is shone at position 20' that satisfies the relationship, forming a second hole 20. Here, the distance S from the center of the first hole 10 to the center of the second hole 20. １This is sometimes called an "interval." 3r １ This means three times the aperture diameter r of the insulating layer (3 × r).

[0150] The second hole, 20, is S １ ≥3r １ It is formed at position 20' that satisfies the relationship, preferably S １ ≥3.2r １ Formed at a position that satisfies the relationship, more preferably S １ ≥3.5r １ It is formed in a position that satisfies the relationship.

[0151] Interval S １ Specific examples include preferably 450 μm or less, more preferably 360 μm or less, even more preferably 300 μm or less, 250 μm or less, or 240 μm or less, preferably 30 μm or more, more preferably 40 μm or more, and even more preferably 60 μm or more.

[0152] The type of laser and conditions under which the second hole may be formed may be the same as, or different from, the type of laser and conditions under which the first hole was formed.

[0153] The opening diameter of the support for the second hole is preferably 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0154] The target opening diameter of the insulating layer for the second hole is preferably 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0155] The aperture diameter r of the insulating layer of the second hole ２Preferably, the diameter is 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more. It is preferable that the opening diameter of the insulating layer of the second hole is the same as the opening diameter of the insulating layer of the first hole.

[0156] As shown in Figures 5 and 6 as an example, when n = 3, the third hole 30 formed after the second hole is formed is the distance from the center of the first hole 10 to the center of the second hole (maximum center-to-center distance S). ｍ It is formed inside a circle with a diameter of ). After the first and second holes are formed by steps (IV-1) and (IV-2), as step (IV-3), the third hole 30, which is formed after the second hole 20 is formed, is formed at the maximum center-to-center distance S from the center of the first hole 10 to the center of the second hole 20. ｍ It is formed inside a circle c with diameter p. That is, a laser is shone on the position 30' between the first hole 10 and the second hole 20 to form the third hole 30. Thus, the distance p from the center of the first hole 10 to the center of the third hole 30 is １ This is the distance S from the center of the first hole 10 to the center of the second hole. １ Shorter than . Forming the third hole 30 at position 30' between the first hole 10 and the second hole 20 means forming the third hole 30 at a position adjacent to the first hole 10 and the second hole 20, and a position adjacent to the first hole 10 and the second hole 20 means a position where there are no other holes between the first hole 10 and the third hole 30, and there are no other holes between the second hole 20 and the third hole 30. Note that the opening diameter of the insulating layer of the second hole 20 is r ２ Let (μm) be the distance from the center of the second hole to the center of the third hole, and S be the distance from the center of the second hole to the center of the third hole. ２ When (μm), S ２ ≥3r ２ It is preferable that it be formed at a position that satisfies the following relationship.

[0157] The third hole is formed when the heat around the first hole (reference numeral 31 in Figures 1 and 2) has cooled. This varies depending on the type of support material and the components contained in the resin composition layer, but for example, after the first hole is formed, it is preferably 300 seconds or more, more preferably 350 seconds or more, even more preferably 400 seconds or more, preferably 1500 seconds or less, more preferably 1200 seconds or less, and even more preferably 1000 seconds or less.

[0158] The distance from the center of the first hole to the center of the third hole (pitch, p in Figure 6) １ From the viewpoint of manufacturing circuit boards that can accommodate narrow pitches, the pitch is preferably 10 μm or more, more preferably 20 μm or more, even more preferably 30 μm or more, preferably 200 μm or less, more preferably 180 μm or less, and even more preferably 150 μm or less.

[0159] The type and conditions of the laser that can form the third hole may be the same as or different from those of the first hole.

[0160] The opening diameter of the support for the third hole is preferably 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0161] The target opening diameter of the insulating layer for the third hole is preferably 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0162] The aperture diameter r of the insulating layer of the third hole ３ Preferably, the diameter is 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more. It is preferable that the opening diameter of the insulating layer of the third hole is the same as the opening diameter of the insulating layer of the first hole.

[0163] When n=3, the method for manufacturing a circuit board of the present invention includes step (IV), that is, after forming a first hole, a second hole is formed, and after forming the second hole, a third hole is formed between the first and second holes. As a result, the opening diameter of the support for the third hole is suppressed to increase, and as a result, a circuit board can be manufactured with a narrower distance between the centers of adjacent holes. If the difference between the distance from the center of the first hole to the center of the third hole (pitch) and the opening diameter of the support for the third hole (pitch - opening diameter of the support for the third hole) is large, it is shown that the opening diameter of the support for the third hole is suppressed to increase. The pitch - opening diameter of the support for the third hole (pitch - opening diameter of the support for the nth hole) is preferably 5 μm or more, more preferably 10 μm or more, and even more preferably 12 μm or more. There is no particular upper limit, but it can be 60 μm or less, etc.

[0164] When n=3, the method for manufacturing a circuit board of the present invention includes step (IV), that is, after forming a first hole, a second hole is formed, and after forming the second hole, a third hole is formed between the first and second holes. As a result, the opening diameter of the insulating layer is suppressed to increase, and a circuit board can be manufactured with a narrower distance between the centers of adjacent holes. If the difference between the opening diameter of the insulating layer of the third hole and the target opening diameter of the insulating layer of the third hole (opening diameter of the insulating layer of the third hole - target opening diameter of the third hole) is small, it is shown that the opening diameter of the insulating layer is suppressed to increase. The difference between the opening diameter of the insulating layer of the third hole and the target opening diameter of the third hole is preferably less than 5 μm, more preferably 1 μm or less, even more preferably 0.5 μm or less, or 0 μm. There is no particular lower limit, but it can be 0 μm or more, etc.

[0165] When forming holes using cycle mode, the player may sequentially cycle through the formation positions of the first, second, and third holes at predetermined intervals, taking shots until the first to third holes reach a predetermined depth.

[0166] The first embodiment of process (IV) was described, for the sake of explanation, as shown in Figures 3 to 6, in the case where n=3 and the centers of the first to third holes are aligned in a straight line. However, in the first embodiment, the centers of the first to third holes may not be aligned in a straight line. Specifically, as shown in Figure 7 as an example, in the case where n=3, the maximum distance S between centers is... ｍ Inside the circle c with diameter S, the center of the third hole is at the maximum center-to-center distance S. ｍ A third hole 30 may be formed at a position other than the one above.

[0167] Furthermore, as shown in Figures 8-9 as an example, the process (IV) may be repeated after the formation of the third hole 30. The fourth hole 40 may be formed in the same manner as the formation of the first to third holes 10, 20, and 30.

[0168] In this case, the opening diameter of the insulating layer of the third hole 30 is r ３ Let (μm) be the distance from the center of the third hole 30 to the center of the fourth hole 40, and S be the distance from the center of the third hole 30 to the center of the fourth hole 40. ３ When (μm), S ３ ≥3r ３ A laser is irradiated onto position 40' that satisfies the relationship, forming a fourth hole 40.

[0169] The type and conditions of the laser used to form the third and fourth holes in this embodiment may be the same as or different from the type and conditions of the laser used to form the first hole in the first embodiment.

[0170] The opening diameter of the support for the nth hole (3 ≤ n, in the case of Figures 8 and 9, n = 4) is preferably 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0171] The target opening diameter of the insulating layer for the nth hole is preferably 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0172] The opening diameter r of the insulating layer of the nth hole ｎ Preferably, the diameter is 150 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, or 80 μm or less, preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more. It is preferable that the opening diameter of the insulating layer of the nth hole is the same as the opening diameter of the insulating layer of the first hole.

[0173] After forming the fourth hole 40, a fifth hole and a sixth hole (not shown) are formed as needed, in the same manner as the first to fourth holes 10, 20, 30, and 40. By repeating this sequence, multiple holes can be formed.

[0174] In the first embodiment of process (IV), for the sake of explanation, the centers of the first to fourth holes are shown in Figures 8-9 in a linear arrangement. However, in the first embodiment, the centers of the first to fourth holes may not be arranged in a linear arrangement, as in Figure 7. Also, in the first embodiment of process (IV), the third hole is described as being formed inside a circle whose diameter is the maximum distance between the centers of the already formed multiple holes (in this case, the distance from the center of the first hole to the center of the second hole). However, for example, the fourth hole may be formed between the first and second holes. Specifically, the first and second holes 10 and 20 are formed (see Figures 3 and 4). After forming the second hole 20, the opening diameter of the insulating layer of the second hole 20 is set to r ２ Let (μm) be the distance from the center of the second hole 20 to the center of the third hole 30, and S be the distance from the center of the second hole 20 to the center of the third hole 30. ２ When (μm), S ２ ≥3r ２ A laser is shone at position 30' that satisfies the relationship, forming a third hole 30 (see Figures 10 and 11). At this time, the maximum distance S between the centers of the multiple holes formed is ｍ Since this is the distance from the center of the first hole 10 to the center of the third hole 30, after forming the third hole 30, the fourth hole 40 is formed using the maximum center-to-center distance S from the center of the first hole 10 to the center of the third hole 30. ｍis formed inside a circle c having a diameter . That is, a laser may be irradiated to a position 40' between the first hole 10 and the second hole 20 to form the fourth hole 40 between the first hole 10 and the second hole 20 (see FIG. 12 and FIG. 13). In this case, the fourth hole 40 is defined such that r is the opening diameter of the insulating layer of the third hole 30 ３ (μm), and S is the distance from the center of the third hole to the center of the fourth hole ３ (μm), then S ３ ≧3r ３ is preferably formed at a position satisfying the above relationship. Further, it is preferable that the distance from the centers of the first hole 10 and the second hole 20 adjacent to the fourth hole to the center of the fourth hole falls within a predetermined range.

[0175] The second embodiment of step (IV) is a case where n=5, as an example shown in FIGS. 14 to 18. Same as the first embodiment, after forming the first hole 10, the second hole 20 is formed at a position satisfying S １ ≧3r １ after forming the second hole 20, the third hole 30 is formed inside a circle c having the maximum center-to-center distance S ｍ as the diameter. The type and conditions of the laser that can be used to form the first to third holes may be the same as or different from the type and conditions of the laser used when forming the first hole in the first embodiment. In addition, the opening diameter of the support in the first to third holes, and the preferable range of the opening diameter of the insulating layer in the first to third holes, etc., are the same as those in the first embodiment.

[0176] After forming the third hole 30, a fourth hole 40 is formed as an example shown in FIGS. 15 and 16. In this case, for the fourth hole 40, when r is the opening diameter of the insulating layer of the third hole 30 ３ (μm), and S is the distance from the center of the third hole 30 to the center of the fourth hole 40 ３ (μm), then S ３ ≧3r ３ is formed by irradiating a laser onto a position 40' satisfying the above relationship.

[0177] After forming the fourth hole 40, as exemplified in FIGS. 17 and 18, the maximum center-to-center distance S of the formed first to fourth holes ｍ is the distance from the center of the first hole 10 to the center of the fourth hole 40. Therefore, after forming the fourth hole 40, the fifth hole 50 is formed after the maximum center-to-center distance S from the center of the first hole 10 to the center of the fourth hole 40 ｍ the fifth hole 50 is formed by irradiating a laser inside a circle c having a diameter of (in the case of FIGS. 17 and 18, position 50' between the second hole 20 and the third hole 30). In this case, for the fifth hole 50, let the opening diameter of the insulating layer of the fourth hole 40 be r ４ (μm), and let the distance from the center of the fourth hole to the center of the fifth hole be S ４ (μm), then S ４ ≧3r ４ is preferably formed at a position that satisfies the relationship. Further, it is preferable that the distances from the centers of the second and third holes 20 and 30 adjacent to the fifth hole 50 to the center of the fifth hole are within a predetermined range.

[0178] The type and conditions of the laser that can be used to form the fourth to fifth holes in this embodiment may be the same as or different from the type and conditions of the laser when forming the first hole in the first embodiment.

[0179] The preferred ranges of the opening diameter in the support for the fourth to fifth holes and the opening diameter of the insulating layer for the fourth to fifth holes are the same as those of the n-th hole in the first embodiment.

[0180] In the second embodiment of step (IV), the third and fifth holes are formed at the maximum center-to-center distance S of the plurality of holes already formed ｍIt is formed inside a circle with a diameter of . Also, in the second embodiment, for the sake of explanation, the centers of the first to fifth holes are shown in Figures 14 to 18 in a linear arrangement, but in the second embodiment, as in the first embodiment, the centers of the holes may not be arranged in a linear arrangement. Also, in the second embodiment of step (IV), after forming the fifth hole 50, step (IV) may be repeated. In this case, the sixth hole (not shown) is formed in the same manner as the first to fifth holes 10, 20, 30, 40, and 50. By repeating this order, it is possible to form multiple holes.

[0181] A third embodiment of process (IV) is the case where n = 7, as shown in Figures 19 and 20. In the third embodiment of process (IV), the first hole 10 is formed, then the second hole 20 is formed, and then the third hole 30 is formed after the second hole 20 is formed. In this case, the opening diameter of the insulating layer of the second hole 20 is r for the third hole 30. ２ Let (μm) be the distance from the center of the second hole 20 to the center of the third hole 30, and S be the distance from the center of the second hole 20 to the center of the third hole 30. ２ When (μm), S ２ ≥3r ２ The holes are formed by irradiating a laser onto position 30' that satisfies the given relationship. The type and conditions of the laser used to form the first to third holes may be the same as or different from those used to form the first hole in the first embodiment. Furthermore, the preferred ranges for the aperture diameter of the support for the first to third holes and the aperture diameter of the insulating layer for the first to third holes are the same as for each hole in the first embodiment.

[0182] After forming the third hole 30, the maximum distance S between the centers of the formed first to third holes is as shown in Figures 21 and 22. ｍ Since this is the distance from the center of the first hole 10 to the center of the third hole 30, after forming the third hole 30, the fourth hole 40 is formed using the maximum center-to-center distance S from the center of the first hole 10 to the center of the third hole 30. ｍA laser is shone on the inside of a circle c with diameter r (in the case of Figures 21 and 22, this is the position between the first hole 10 and the second hole 20, and the position 40' adjacent to the first hole 10 and the second hole 20) to form the fourth hole 40. In this case, the fourth hole 40 is formed by reducing the aperture diameter of the insulating layer of the third hole 30 to r ３ Let (μm) be the distance from the center of the third hole to the center of the fourth hole, and S be the distance from the center of the third hole to the center of the fourth hole. ３ When (μm), S ３ ≥3r ３ It is preferable that the hole be formed at a position that satisfies the following relationship. Furthermore, it is preferable that the distance from the centers of the first and second holes 10 and 20 adjacent to the fourth hole to the center of the fourth hole is within a predetermined range.

[0183] After forming the fourth hole 40, as shown in Figures 23 and 24 as an example, the maximum distance S between centers is formed. ｍ A laser is shone on the inside of a circle c with diameter r (in the case of Figures 23 and 24, this is the position between the second hole 20 and the third hole 30, and the position 50' adjacent to the second hole 20 and the third hole 30) to form the fifth hole 50. In this case, the opening diameter of the insulating layer of the fourth hole 40 is r in the fifth hole 50. ４ Let (μm) be the distance from the center of the fourth hole 40 to the center of the fifth hole 50, and S ４ When (μm), S ４ ≥3r ４ It is preferable that the hole be formed at a position that satisfies the following relationship. Furthermore, it is preferable that the distance from the centers of the second and third holes 20 and 30 adjacent to the fifth hole to the center of the fifth hole 50 is within a predetermined range.

[0184] After forming the fifth hole 50, as shown in Figures 25 and 26 as an example, the maximum distance S between centers is formed. ｍ A laser is shone into the inside of a circle c with diameter r (in the case of Figures 25 and 26, this is the position between the second hole 20 and the fourth hole 40, and the position 60' adjacent to the second hole 20 and the fourth hole 40) to form the sixth hole 60. In this case, the sixth hole 60 has an aperture diameter of r of the insulating layer of the fifth hole 50. ５Let (μm) be the distance from the center of the fifth hole 50 to the center of the sixth hole 60, and S be the distance from the center of the fifth hole 50 to the center of the sixth hole 60. ５ When (μm), S ５ ≥3r ５ It is preferable that the sixth hole is formed at a position that satisfies the following relationship. Furthermore, it is preferable that the distance from the centers of the second and fourth holes 20 and 40 adjacent to the sixth hole to the center of the sixth hole 60 is within a predetermined range.

[0185] After forming the sixth hole 60, as shown in Figures 27 and 28 as an example, the maximum center-to-center distance S ｍ A laser is shone onto the inside of a circle c with diameter r (in the case of Figures 27 and 28, this is the position between the third hole 30 and the fifth hole 50, and the position 70' adjacent to the third hole 30 and the fifth hole 50) to form the seventh hole 70. In this case, the seventh hole 70 has an aperture diameter of r of the insulating layer of the sixth hole 60. ６ Let (μm) be the distance from the center of the sixth hole 60 to the center of the seventh hole 70, and S ６ When (μm), S ６ ≥3r ６ It is preferable that the hole be formed at a position that satisfies the following relationship. Furthermore, it is preferable that the distance from the centers of the third and fifth holes 30 and 50 adjacent to the seventh hole to the center of the seventh hole 70 is within a predetermined range.

[0186] The type and conditions of the laser used to form the fourth to seventh holes in this embodiment may be the same as or different from the type and conditions of the laser used to form the first hole in the first embodiment.

[0187] The preferred range for the opening diameter of the support for the fourth to seventh holes, and the preferred range for the opening diameter of the insulating layer for the fourth to seventh holes, is the same as that for the nth hole in the first embodiment.

[0188] In the third embodiment of process (IV), for the sake of explanation, the centers of the first to seventh holes are shown in Figures 18 to 27 in a linear arrangement. However, in the third embodiment, the centers of the first to seventh holes may not be aligned in a linear arrangement. Furthermore, in the third embodiment of process (IV), after forming the seventh hole 70, process (IV) may be repeated. In this case, the eighth hole (not shown) is formed in the same manner as the first to seventh holes 10, 20, 30, 40, 50, 60, and 70. By repeating this sequence, multiple holes can be formed.

[0189] <Optional steps> After step (IV), the process may include (V) a step of peeling off the support from the resin sheet with the support, (VI) a step of roughening the insulating layer, and (VII) a step of forming a conductive layer.

[0190] -Step (V)- In step (V), the support is peeled off to expose the insulating layer. As one embodiment of the method for peeling off the support, the support is peeled off by pulling it relative to the insulating layer. For example, the insulating layer and the substrate may be transported with the support fixed, and the support may be peeled off. Alternatively, for example, the support may be pulled with the insulating layer and the substrate fixed, and the support may be peeled off.

[0191] - Process (VI) - In process (VI), the surface of the insulating layer is roughened, and smear (resin residue) is removed from the insulating layer.

[0192] The procedure and conditions for the roughening treatment are not particularly limited, and known procedures and conditions commonly used when forming the insulating layer of a circuit board can be employed. For example, the roughening treatment may be carried out by applying swelling treatment with a swelling solution, oxidation treatment with an oxidizing agent, and neutralization treatment with a neutralizing solution to the insulating layer in this order.

[0193] Examples of swelling solutions used for roughening treatment include alkaline solutions and surfactant solutions, with alkaline solutions being preferred. Sodium hydroxide solution and potassium hydroxide solution are more preferred as the alkaline solution. Examples of commercially available swelling solutions include "Swelling Dip Securigans P" and "Swelling Dip Securigans SBU" manufactured by Atotec Japan. The swelling treatment with the swelling solution can be carried out, for example, by immersing the insulating layer in a swelling solution at 30°C to 90°C for 1 to 20 minutes. From the viewpoint of suppressing the swelling of the resin of the insulating layer to an appropriate level, it is preferable to immerse the insulating layer in a swelling solution at 40°C to 80°C for 5 to 15 minutes.

[0194] Examples of oxidizing agents used in the roughening treatment include alkaline permanganate solutions obtained by dissolving potassium permanganate or sodium permanganate in an aqueous solution of sodium hydroxide. The oxidation treatment with an oxidizing agent such as an alkaline permanganate solution is preferably carried out by immersing the insulating layer in an oxidizing agent solution heated to 60°C to 100°C for 10 to 30 minutes. Furthermore, the concentration of permanganate in the alkaline permanganate solution is preferably 5% to 10% by mass. Examples of commercially available oxidizing agents include alkaline permanganate solutions such as "Concentrate Compact CP" and "Dosing Solution Securigans P" manufactured by Atotec Japan.

[0195] As the neutralizing solution used for roughening treatment, an acidic aqueous solution is preferred, and a commercially available example is "Reduction Solution Securigant P" manufactured by Attec Japan. Neutralization treatment with a neutralizing solution can be carried out by immersing the treated surface, which has been oxidized with an oxidizing agent, in a neutralizing solution at 30°C to 80°C for 5 to 30 minutes. From the viewpoint of workability, it is preferable to immerse the object that has been oxidized with an oxidizing agent in a neutralizing solution at 40°C to 70°C for 5 to 20 minutes.

[0196] -Step (VII)- In step (VII), a conductive layer is formed on the insulating layer. If the method for manufacturing the circuit board includes (VI), it is generally preferable that the step of forming the conductive layer (VII) be performed after step (VII).

[0197] The conductive material used in the conductive layer is not particularly limited. In a preferred embodiment, the conductive layer contains one or more metals selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin, and indium. The conductive layer may be a single-metal layer or an alloy layer. Examples of alloy layers include layers formed from alloys of two or more metals selected from the above group (e.g., nickel-chromium alloy, copper-nickel alloy, and copper-titanium alloy). Among these, from the viewpoint of versatility in conductive layer formation, cost, and ease of patterning, single-metal layers of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or alloy layers of nickel-chromium alloy, copper-nickel alloy, or copper-titanium alloy are preferred, single-metal layers of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or alloy layers of nickel-chromium alloy are more preferred, and single-metal layers of copper are even more preferred.

[0198] The conductive layer may have a single-layer structure, or it may have a multi-layer structure including two or more single-metal layers or alloy layers made of different types of metals or alloys. When the conductive layer has a multi-layer structure, the layer in contact with the insulating layer is preferably a single-metal layer of chromium, zinc, or titanium, or an alloy layer of nickel-chromium alloy.

[0199] The thickness of the conductor layer depends on the design of the circuit board, but is preferably 3 μm to 35 μm, and more preferably 5 μm to 30 μm.

[0200] The conductor layer may be formed by plating. For example, a conductor layer having a desired wiring pattern can be formed by plating the surface of the insulating layer using conventionally known techniques such as the semi-additive method or the fully additive method. From the viewpoint of ease of manufacture, the semi-additive method is preferred. An example of forming the conductor layer by the semi-additive method is shown below.

[0201] First, an electroless plating layer (plating seed layer) is formed on the surface of the insulating layer by electroless plating. Next, a mask pattern is formed on the formed electroless plating layer, exposing a portion of the electroless plating layer corresponding to the desired wiring pattern. After forming an electroplating layer on the exposed electroless plating layer by electroplating, the mask pattern is removed. Subsequently, the unnecessary electroless plating layer can be removed by etching to form a conductor layer having the desired wiring pattern.

[0202] When a conductive layer is formed on an insulating layer, the manufacturing method of the circuit board may typically include annealing after the formation of the conductive layer. Annealing can improve the adhesion between the insulating layer and the conductive layer. Annealing can be performed, for example, by heating at 100°C to 200°C for 20 to 180 minutes.

[0203] In the method for manufacturing a circuit board, each of the above-described steps may be performed only once or repeated two or more times. For example, steps (I) to (VII) may be repeatedly performed to form a circuit board having a multilayer structure, such as a multilayer printed wiring board, which comprises multiple insulating layers and conductive layers.

[0204] The method for manufacturing a circuit board may include any additional steps in addition to the steps described above. For example, the method for manufacturing a circuit board may include a step of providing a semiconductor chip so as to be bonded to a conductor layer. Specifically, when manufacturing a circuit board for a semiconductor chip package that includes a semiconductor chip, the method for manufacturing the circuit board may include a step of providing the semiconductor chip. The semiconductor chip can employ appropriate conditions that allow the terminal electrodes of the semiconductor chip to be conductively connected to the conductor layer formed on the insulating layer. For example, conditions used in flip-chip mounting can be employed. The semiconductor chip may also be bonded via an insulating adhesive or by reflow soldering. Furthermore, if necessary, the provided semiconductor chip may be filled with mold underfill material. The method for manufacturing a circuit board may also include, for example, a step of forming a sealing layer, a step of forming a solder resist layer, and a step of dicing the manufactured circuit board into individual pieces.

[0205] Examples of circuit boards include printed circuit boards and semiconductor chip packages. Examples of semiconductor chip packages include FC-CSP, MIS-BGA packages, ETS-BGA packages, fan-out type WLP (Wafer Level Package), fan-in type WLP, fan-out type PLP (Panel Level Package), and fan-in type PLP. In these semiconductor chip packages, it is preferable to form a rewiring layer using an insulating layer obtained by curing the resin composition layer described above. However, the circuit boards are not limited to those exemplified herein.

[0206] [Semiconductor Devices] Circuit boards can be used in the manufacture of semiconductor devices. Semiconductor devices include the circuit boards described above. Examples of semiconductor devices include various types of semiconductor devices used in electrical products (e.g., computers, mobile phones, smartphones, tablet devices, wearable devices, digital cameras, medical equipment, and televisions) and vehicles (e.g., motorcycles, automobiles, trains, ships, and aircraft). These semiconductor devices may be manufactured, for example, by a method that includes manufacturing circuit boards by the manufacturing method described above.

[0207] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these examples. In the following description, "parts" and "%" refer to "parts by mass" and "mass%" respectively, unless otherwise specified. Unless otherwise specified, the temperature and pressure conditions were room temperature (25°C) and atmospheric pressure (1 atm).

[0208] <Example 1: Preparation of a resin sheet with a support> (1) Preparation of resin varnish 1 5 parts of bisphenol type epoxy resin (epoxy equivalent of approximately 165 g / eq., "ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd., a 1:1 mixture of bisphenol A type and bisphenol F type), 10 parts of bixylenol type epoxy resin (epoxy equivalent of approximately 185 g / eq., "YX4000HK" manufactured by Mitsubishi Chemical Corporation), 10 parts of biphenyl type epoxy resin (epoxy equivalent of approximately 290 g / eq., "NC3000H" manufactured by Nippon Kayaku Co., Ltd.), and 10 parts of phenoxy resin ("YL7553BH30" manufactured by Mitsubishi Chemical Corporation, a methyl ethyl ketone (MEK) solution with a solid content of 30% by mass) were heated and dissolved in 20 parts of solvent naphtha while stirring. After cooling to room temperature, add 12 parts of naphthol-based curing agent (hydroxyl group equivalent 215 g / eq., Nippon Steel Chemical & Material Co., Ltd. "SN-485", MEK solution with 60% solids), 8 parts of triazine skeleton-containing phenol novolac-based curing agent (hydroxyl group equivalent 125 g / eq., DIC Corporation "LA-7054", MEK solution with 60% solids), 4 parts of curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution with 2% solids by mass), and flame retardant (Sanko Co., Ltd. "HCA-HQ", 10 2 parts of (2,5-dihydroxyphenyl)-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide (average particle size 1 μm), 3 parts of rubber particles (Aica Kogyo Co., Ltd. "Stafiloid AC3816N"), and spherical silica (Admatex Co., Ltd. "SOC1", average particle size 0.24 μm, particles larger than 3 μm removed by classification, carbon content per unit surface area 0.36 mg / m²) surface-treated with an aminosilane coupling agent (Shin-Etsu Chemical Co., Ltd. "KBM573"). ２ ) 68 parts were mixed and uniformly dispersed in a high-speed rotary mixer to prepare resin varnish 1.

[0209] (2) Preparation of the resin sheet 1 with support As a support, a PEN film (Toyobo Co., Ltd. "Q51", thickness 25 μm) was prepared, which had been treated with an alkyd resin-based release agent (Lintec Corporation "AL-5"). A resin varnish 1 was applied to the release surface of the support using a die coater and dried at 80°C to 110°C (average 100°C) for 1.5 minutes to form a resin composition layer. The thickness of the resin composition layer was 10 μm. Next, a polypropylene film (Oji Specialty Paper Co., Ltd. "Alfan MA-411", thickness 15 μm) was laminated as a protective film on the side of the resin composition layer that was not bonded to the support, so that the rough surface of the protective film was bonded to the resin composition layer, and a resin sheet 1 was prepared.

[0210] <Fabrication Example 2: Fabrication of Resin Sheet 2 with Support> In Fabrication Example 1, resin varnish 1 was replaced with resin varnish 2 prepared as follows. Except for the above, the resin sheet 2 with support was fabricated in the same manner as in Fabrication Example 1.

[0211] (1) Preparation of resin varnish 2 In the preparation of resin varnish 1, spherical silica (SOC1 manufactured by Admatex Co., Ltd., average particle size 0.24 μm, particles larger than 3 μm removed by classification, carbon content per unit surface area 0.36 mg / m²) was surface-treated with an aminosilane coupling agent (KBM573 manufactured by Shin-Etsu Chemical Co., Ltd.) ２ The amount of ) was changed from 68 parts to 45 parts. Except for the above, resin varnish 2 was prepared in the same manner as the preparation of resin varnish 1.

[0212] <Fabrication Example 3: Fabrication of Resin Sheet 3 with Support> In Fabrication Example 1, the resin varnish 1 was replaced with resin varnish 3 prepared as follows. Except for the above, the resin sheet 3 with support was fabricated in the same manner as in Fabrication Example 1.

[0213] (1) Preparation of resin varnish 3 In the preparation of resin varnish 1, spherical silica (SOC1 manufactured by Admatex Co., Ltd., average particle size 0.24 μm, particles larger than 3 μm removed by classification, carbon content per unit surface area 0.36 mg / m²) was surface-treated with an aminosilane coupling agent (KBM573 manufactured by Shin-Etsu Chemical Co., Ltd.) ２The amount of ) was changed from 68 parts to 105 parts. Except for the above, resin varnish 3 was prepared in the same manner as the preparation of resin varnish 1.

[0214] <Fabrication Example 4: Fabrication of Resin Sheet 4 with Support> In Fabrication Example 1, the resin varnish 1 was replaced with resin varnish 4 prepared as follows. Except for the above, the resin sheet 4 with support was fabricated in the same manner as in Fabrication Example 1.

[0215] (1) Preparation of resin varnish 4 In the preparation of resin varnish 1, 1) the amount of triazine skeleton-containing phenol novolac curing agent (hydroxyl group equivalent 125 g / eq., DIC Corporation "LA-7054", MEK solution with 60% solids) was changed from 8 parts to 3 parts, and 2) 12 parts of naphthol curing agent (hydroxyl group equivalent 215 g / eq., Nippon Steel & Sumitomo Metal Chemical Co., Ltd. "SN-485", MEK solution with 60% solids) was changed to 16 parts of active ester curing agent (DIC Corporation "HPC-8000-65T", active group equivalent approximately 223 g / eq., toluene solution with 65% by mass of nonvolatile components). Except for the above, resin varnish 4 was prepared in the same manner as the preparation of resin varnish 1.

[0216] <Fabrication Example 5: Fabrication of Resin Sheet 5 with Support> In Fabrication Example 1, the resin varnish 1 was replaced with resin varnish 5 prepared as follows. Except for the above, the resin sheet 5 with support was fabricated in the same manner as in Fabrication Example 1.

[0217] (1) Preparation of resin varnish 5 In the preparation of resin varnish 1, 1) the amount of triazine skeleton-containing phenol novolac curing agent (hydroxyl group equivalent 125 g / eq., DIC Corporation "LA-7054", MEK solution with 60% solids) was changed from 8 parts to 2 parts, 2) the amount of naphthol curing agent (hydroxyl group equivalent 215 g / eq., Nippon Steel & Sumitomo Metal Chemical Co., Ltd. "SN-485", MEK solution with 60% solids) was changed from 12 parts to 3 parts, 3) spherical silica (Admatex Corporation "SOC1", average particle size 0.24 μm, particles larger than 3 μm removed by classification, carbon content per unit surface area 0.36 mg / m²) surface-treated with an aminosilane coupling agent (Shin-Etsu Chemical Co., Ltd. "KBM573") ２ The amount of ) was changed from 68 parts to 55 parts. Except for the above, resin varnish 5 was prepared in the same manner as the preparation of resin varnish 1.

[0218] <Fabrication Example 6: Fabrication of Resin Sheet 6 with Support> In Fabrication Example 1, the resin varnish 1 was replaced with a resin varnish 6 prepared as follows. Except for the above, the resin sheet 6 with support was fabricated in the same manner as in Fabrication Example 1.

[0219] (1) Preparation of resin varnish 6 In the preparation of resin varnish 1, 1) the amount of triazine skeleton-containing phenol novolac curing agent (hydroxyl group equivalent 125 g / eq., DIC Corporation "LA-7054", MEK solution with 60% solids) was changed from 8 parts to 4 parts, 2) the amount of naphthol curing agent (hydroxyl group equivalent 215 g / eq., Nippon Steel & Sumitomo Metal Chemical Co., Ltd. "SN-485", MEK solution with 60% solids) was changed from 12 parts to 6 parts, 3) spherical silica (Admatex Corporation "SOC1", average particle size 0.24 μm, particles larger than 3 μm removed by classification, carbon content per unit surface area 0.36 mg / m²) surface-treated with an aminosilane coupling agent (Shin-Etsu Chemical Co., Ltd. "KBM573") ２ The amount of ) was changed from 68 parts to 59 parts. Except for the above, resin varnish 6 was prepared in the same manner as the preparation of resin varnish 1.

[0220] <Fabrication Example 7: Fabrication of Resin Sheet 7 with Support> In Fabrication Example 1, the resin varnish 1 was replaced with resin varnish 7 prepared as follows. Except for the above, the resin sheet 7 with support was fabricated in the same manner as in Fabrication Example 1.

[0221] (1) Preparation of resin varnish 7 In the preparation of resin varnish 1, spherical silica (SOC1 manufactured by Admatex Co., Ltd., average particle size 0.24 μm, particles larger than 3 μm removed by classification, carbon content per unit surface area 0.36 mg / m²) was surface-treated with an aminosilane coupling agent (KBM573 manufactured by Shin-Etsu Chemical Co., Ltd.) ２ The amount of ) was changed from 68 parts to 192 parts. Except for the above, resin varnish 7 was prepared in the same manner as the preparation of resin varnish 1.

[0222] [Example 1] (1) Surface preparation of the inner layer circuit board A glass cloth substrate epoxy resin double-sided laminate (copper foil thickness 18 μm, substrate thickness 0.3 mm, size 500 mm x 500 mm, Panasonic "R5715 ES") on which the inner layer circuit was formed was etched by 1 μm on both sides using MEC "CZ8100" to roughen the copper surface.

[0223] (2) Lamination of support-attached resin sheet The protective film of support-attached resin sheet 1 (size 494 mm x 494 mm) was peeled off and laminated on both sides of the inner layer circuit board using a batch-type vacuum pressure laminator (Nichigo Morton Co., Ltd., 2-stage build-up laminator, CVP700) so that the resin composition layer was in contact with the inner layer circuit board. Lamination was carried out by reducing the pressure to 13 hPa or less by depressurizing for 30 seconds, and then pressing at 100°C and a pressure of 0.74 MPa for 30 seconds. Next, a hot press was performed at 100°C and a pressure of 0.5 MPa for 60 seconds.

[0224] (3) The resin sheet 1 with a support having a cured resin composition layer was heated at 100°C for 30 minutes, and then at 170°C for 30 minutes to heat-cur the resin composition layer and form an insulating layer. The obtained substrate is referred to as "evaluation substrate A".

[0225] (4) Via Hole Formation Evaluation A laser was irradiated onto the support of substrate A to form small-diameter via holes (first holes) in the insulating layer. A UV-YAG laser processing machine (Via Mechanics Co., Ltd. "LU-2L212 / M50L", 60 burst shots, target via diameter (target aperture diameter) of the insulating layer 40 μm) was used to form the via holes. The aperture diameter r of the first hole was 40 μm.

[0226] After forming the first hole, a second hole was formed at an interval of 160 μm under the same conditions as the first hole.

[0227] After forming the second hole, a third hole was formed between the first and second holes at a pitch of 80 μm, under the same conditions as the first hole. The substrate after forming the first, second, and third holes in this order is referred to as "evaluation substrate B".

[0228] <Measurement of Support Aperture Diameter> For evaluation substrate B, the aperture diameter of the support for the third hole was measured using a digital microscope (Keyence VHX-7000). The support aperture diameter was also judged according to the following criteria (in the evaluation criteria, X = pitch (μm) - aperture diameter of the support for the third hole (μm)). ◎: X is 10 μm or more 〇: X is less than 10 μm and 5 μm or more ×: X is less than 5 μm

[0229] <Evaluation of the Insulating Layer Aperture Diameter> For evaluation substrate B, the support was peeled off and the aperture diameter of the insulating layer of the third hole was measured using a digital microscope (Keyence VHX-7000). The aperture diameter of the insulating layer was judged according to the following criteria (in the evaluation criteria, Y = aperture diameter of the insulating layer of the third hole (μm) - target aperture diameter of the third hole (μm)). ○: Y is less than 1 μm △: Y is 1 μm or more and less than 5 μm ×: Y is 5 μm or more

[0230] <Measurement of the degree of curing of the resin composition layer> A resin sheet 1 with a support was laminated onto a polyimide film (Ube Industries, Ltd. "UPIREX S") using a batch-type vacuum pressure laminator (Nikko Materials Co., Ltd. "CVP700", a two-stage build-up laminator). The lamination process was performed by reducing the pressure to 13 hPa or less for 30 seconds, and then pressing at 100°C and 0.74 MPa for 30 seconds. Subsequently, the resin composition layer in the resin sheet 1 with the support was heat-cured at 100°C for 30 minutes, and then at 170°C for 30 minutes, after which the polyimide film and support were sequentially peeled off. The resulting cured product is referred to as the "reaction rate evaluation sample". For the resin sheet 1 with support, a laminate of the resin sheet 1 with support and the polyimide film before heat curing was prepared as a "control sample".

[0231] <Calculation of degree of curing in reaction rate evaluation sample> The reaction rate evaluation sample of the resin sheet 1 with support was subjected to FT-IR (FT / IR-4600 manufactured by JASCO Corporation, Fourier transform infrared analyzer), and a predetermined peak derived from the epoxy group of the epoxy resin (specifically, peak top 4530 cm) was obtained. －１ The peaks of the fragrance ring, and a predetermined peak derived from the C-H bond of the fragrance ring (specifically, the peak top at 4621 cm²).－１ and 4676cm －１ The intensity of the peak (of which) was measured. Next, the intensity of a predetermined peak (specifically, the peak top at 4530 cm²) derived from the epoxy group of the epoxy resin of the reaction rate evaluation sample was measured. －１ The peak area is the intensity of a predetermined peak derived from the C-H bond of the aromatic ring (specifically, the peak top is 4621 cm²). －１ and 4676cm －１ The value was calculated by dividing it by the sum of the peak areas (this is referred to as the "post-reaction division value").

[0232] Similarly, a control sample of the resin sheet 1 with support was subjected to FT-IR, and the intensity of the predetermined peaks derived from the epoxy group and the predetermined peaks derived from the aromatic ring were measured. Next, the intensity of the predetermined peak derived from the epoxy group of each control sample (specifically, the peak top at 4530 cm⁻¹) was measured. －１ The peak area is the intensity of a predetermined peak derived from the C-H bond of the aromatic ring (specifically, the peak top is 4621 cm²). －１ and 4676cm －１ The value obtained by dividing by the sum of the peak areas was calculated (this is called the "pre-reaction division value").

[0233] The degree of hardening was calculated using the following formula (1): Degree of hardening = (1 - post-reaction division value / pre-reaction division value) × 100 ... (1)

[0234] [Example 2] In Example 1, the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 240 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0235] [Example 3] In Example 1, the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 320 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0236] [Example 4] In Example 1, the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 400 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0237] [Example 5] In Example 1, "(4) Formation of a beer hall" was changed to "(4-1) Formation of a beer hall" as described below. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0238] (4-1) Via Hole Formation Evaluation A small-diameter via hole (first hole) was formed in the insulating layer by irradiating a laser from the support of substrate A. A UV-YAG laser processing machine (Via Mechanics Co., Ltd. "LU-2L212 / M50L", 30 shots, target via diameter (target aperture diameter) of the insulating layer 40 μm) was used to form the via holes. After irradiating the position of the first hole with 30 shots, the laser was irradiated at the position of the second hole at an interval of 160 μm under the same conditions as the first hole. Then, the laser was irradiated at the position of the third hole between the first and second holes at a pitch of 80 μm under the same conditions as the first hole. Furthermore, the laser was irradiated in the order of the first hole, second hole, and third hole to create openings.

[0239] [Example 6] In Example 1, 1) the pitch (distance from the center of the first hole to the center of the third hole) was changed from 80 μm to 70 μm, and 2) the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 300 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0240] [Example 7] In Example 1, 1) the pitch (distance from the center of the first hole to the center of the third hole) was changed from 80 μm to 100 μm, 2) the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 400 μm, 3) the target via diameter of the insulating layer was changed from 40 μm to 50 μm, and 4) the opening diameter of the insulating layer of the first hole was changed from 40 μm to 50 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above items.

[0241] [Example 8] In Example 1, the resin sheet with support 1 was replaced with a resin sheet with support 2. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0242] [Example 9] In Example 1, the resin sheet with support 1 was replaced with a resin sheet with support 3, and the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 240 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0243] [Example 10] In Example 1, the resin sheet with support 1 was replaced with a resin sheet with support 7, and the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 240 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0244] [Example 11] In Example 1, the resin sheet with support 1 was replaced with a resin sheet with support 4, and the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 240 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0245] [Example 12] In Example 1, the resin sheet with support 1 was replaced with a resin sheet with support 5, and the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 240 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0246] [Example 13] In Example 1, the resin sheet with support 1 was replaced with a resin sheet with support 6, and the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 240 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0247] [Example 14] In Example 1, the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 240 μm, and "(4) Formation of via holes" was changed to "(4-2) Formation of via holes" as described below. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0248] (4-2) Via hole formation evaluation A laser was irradiated onto the support of substrate A to form small diameter via holes (first holes) in the insulating layer. CO ２ A laser processing machine (Via Mechanics Co., Ltd. "LC-2Q252 / 2C", 2-burst shots, target via diameter (target aperture diameter) of the insulating layer 40 μm) was used. The aperture diameter r of the first hole was 40 μm.

[0249] After forming the first hole, a second hole was formed at an interval of 240 μm under the same conditions as the first hole.

[0250] After forming the second hole, a third hole was formed between the first and second holes at a pitch of 80 μm, under the same conditions as the first hole.

[0251] [Comparative Example 1] In Example 1, the interval (distance from the center of the first hole to the center of the second hole) was changed from 160 μm to 80 μm. Evaluation and other procedures were carried out in the same manner as in Example 1, except for the above.

[0252] [Comparative Example 2] In Example 14, the interval (distance from the center of the first hole to the center of the second hole) was changed from 240 μm to 80 μm. Evaluation and other procedures were carried out in the same manner as in Example 14, except for the above.

[0253] *The content of each component in the table is calculated on a non-volatile basis. *In the table, the content of component (a) represents the content when the non-volatile component in the resin composition layer is taken as 100% by mass.

[0254] 1 Substrate 2 Insulating layer 3 Support 31 Support around the first hole 32 Area where heat is not transferred 10 First hole 20 Second hole 20' Position satisfying the relationship S≧3r 30 Third hole 30' Position between the first hole 10 and the second hole 20, or S ２ ≥3r ２ Positions that satisfy the relationship 40 The fourth hole 40' Positions adjacent to the first hole 10 and the second hole 20, or S ３ ≥3r３ The following positions satisfy the relationship: 50 The fifth hole 50' The position between the second hole 20 and the third hole 30 60 The sixth hole 60' The position adjacent to the second hole 20 and the fourth hole 40 70 The seventh hole 70' The position adjacent to the third hole 30 and the fifth hole 50 p １ The distance r from the center of the first hall to the center of the third hall. １ The aperture diameter S of the insulating layer of the first hole １ The distance r from the center of the first hall to the center of the second hall. ２ The aperture diameter S of the insulating layer of the second hole ２ The distance r from the center of the second hall to the center of the third hall. ３ The aperture diameter S of the insulating layer of the third hole ３ The distance r from the center of the third hall to the center of the fourth hall. ４ The aperture diameter S of the insulating layer of the fourth hole ４ The distance r from the center of the fourth hole to the center of the fifth hole ５ The aperture diameter S of the insulating layer of the fifth hole ５ The distance r from the center of the fifth hole to the center of the sixth hole. ６ The aperture diameter S of the insulating layer of the sixth hole ６ Distance S from the center of the 6th hole to the center of the 7th hole ｍ Maximum distance between centers

Claims

1. A method for manufacturing a circuit board, comprising: (I) preparing a resin sheet with a support comprising a support and a resin composition layer provided on the support; (II) laminating the resin sheet with the support onto a substrate; (III) thermally curing the resin composition layer to form an insulating layer; and (IV) continuously forming N holes (N is an integer of 3 or more) in the support and the insulating layer using a laser, wherein step (IV) includes (IV-1) forming a first hole which is the first hole to be formed; (IV-2) forming a second hole which is the second hole to be formed; and (IV-3) forming the nth hole which is the nth hole to be formed (n is an integer satisfying 3 ≤ n ≤ N), and the second hole is formed with an aperture diameter of r of the insulating layer of the first hole １ Let (μm) be the distance from the center of the first hole to the center of the second hole, and S be the distance from the center of the first hole to the center of the second hole. １ When (μm), S １ ≥3r １ The nth hole is formed at a position that satisfies the following relationship, and the opening diameter of the insulating layer of the (n-1)th hole is r ｎ－１ Let (μm) be the distance from the center of the (n-1)th hole to the center of the nth hole, and S be the distance from the center of the (n-1)th hole to the center of the nth hole. ｎ－１ When (μm), S ｎ－１ ≥3r ｎ－１ A method for manufacturing a circuit board, wherein the holes are formed at positions that satisfy the following relationship, and at least one of the nth holes from the third hole to the nth hole formed as the Nth hole is formed inside a circle whose diameter is the maximum inter-center distance among the inter-center distances between the already formed multiple holes.

2. The method for manufacturing a circuit board according to claim 1, wherein the resin composition layer comprises (a) an inorganic filler and (b) a thermosetting resin.

3. The method for manufacturing a circuit board according to claim 2, wherein the content of component (a) is 60% by mass or more and 80% by mass or less, when the nonvolatile components contained in the resin composition layer are taken as 100% by mass.

4. The method for manufacturing a circuit board according to claim 1, wherein the degree of hardening of the insulating layer before the post-processing step (IV) after step (III) is 40% or more.

5. The method for manufacturing a circuit board according to claim 1, wherein the opening diameter of the insulating layer of the nth hole formed is 150 μm or less.

6. The method for manufacturing a circuit board according to claim 1, wherein the opening diameter of the support for the nth hole formed is 150 μm or less.

7. The method for manufacturing a circuit board according to claim 1, wherein the distance from the center of the first hole to the center of the nth hole formed inside a circle whose diameter is the maximum intercenter distance is 200 μm or less.

8. The method for manufacturing a circuit board according to claim 1, wherein the distance from the center of the first hole to the center of the nth hole formed inside a circle whose diameter is the maximum distance between centers is shorter than the distance from the center of the first hole to the center of the second hole.

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