JP6408847B2 - Resin composition - Google Patents

Description

  The present invention relates to a resin composition containing an epoxy resin and an active ester curing agent.

  In recent years, mobile terminals such as smart phones and tablets have rapidly spread. As a result, there is an increasing need for communication and processing of a larger amount of data. Equipments such as data center and information base station servers are required to support high-speed transmission. In order to achieve high-speed transmission, it is necessary to reduce signal loss. For this reason, a thermosetting resin having a low dielectric property (dielectric constant, dielectric loss tangent) is used for a printed wiring board or the like constituting the apparatus.

  For example, as disclosed in Patent Document 1 below, a resin composition containing an epoxy resin and an active ester curing agent is known. In this resin composition, a hydroxyl group having high polarity at the time of reaction is not generated from the epoxy resin, and the cured product obtained exhibits a very low dielectric loss tangent.

JP 2014-159512 A

  However, since the resin composition containing an epoxy resin and an active ester curing agent has low polarity, its suitability is low in a semi-additive process (SAP) which is a fine wiring processing process of a printed wiring board. Specifically, the adhesiveness between the cured product of the resin composition and the conductor portion is low, and floating and peeling are likely to occur. Furthermore, resin residues (smear) tend to remain on the via bottom during laser via processing for electrical connection between layers. Although the resin composition using the active ester curing agent can lower the dielectric loss tangent, it is difficult to achieve both high adhesion between the cured product and the conductor and suppression of residual smear during via processing. It is.

  The objective of this invention is providing the resin composition which can improve the adhesiveness of the hardened | cured material after hardening, and a conductor part, and can reduce the residual of a smear at the time of via | veer processing.

  According to a broad aspect of the present invention, at least one epoxy resin and at least two curing agents are included, the at least two curing agents include an active ester curing agent, and all of the resin compositions The ratio of the total weight% of nitrogen atoms contained in 100% by weight of the epoxy resin to the total weight% of nitrogen atoms contained in 100% by weight of all the curing agents in the resin composition is 1/3. As described above, a resin composition of 1 or less is provided.

  In a specific aspect of the resin composition according to the present invention, the at least two kinds of curing agents include an aminotriazine-modified phenol curing agent or an aminotriazine-modified cresol curing agent as a curing agent other than the active ester curing agent.

  In a specific aspect of the resin composition according to the present invention, the total number of reactive groups of all the curing agents in the resin composition, the aminotriazine-modified phenol curing agent and the aminotriazine-modified cresol in the resin composition. The ratio of the curing agent to the total number of reactive groups is 2.5 or more and 10 or less.

  On the specific situation with the resin composition which concerns on this invention, the dielectric loss tangent in the frequency of 5.8 GHz of the hardened | cured material hardened | cured at 150 degreeC or more for 0.5 hour or more is 0.007 or less.

  On the specific situation with the resin composition which concerns on this invention, the said at least 1 sort (s) of epoxy resin contains the epoxy resin whose epoxy equivalent is 120 or less.

  On the specific situation with the resin composition which concerns on this invention, hardening is performed in the environment which is not exposed to air.

  On the specific situation with the resin composition which concerns on this invention, it is an insulating material used for a buildup wiring board.

  The resin composition according to the present invention includes at least one epoxy resin and at least two curing agents, and the at least two curing agents include an active ester curing agent, and include all of the resin compositions in the resin composition. The ratio of the total weight% of nitrogen atoms contained in 100% by weight of the epoxy resin to the total weight% of nitrogen atoms contained in 100% by weight of all the curing agents in the resin composition is 1/3. As described above, since it is 1 or less, it is possible to improve the adhesion between the cured product and the conductor part after curing, and to reduce the remaining smear during via processing.

FIG. 1 is a partially cutaway front sectional view schematically showing a multilayer substrate using a resin composition according to an embodiment of the present invention.

  Details of the present invention will be described below.

(Resin composition)
The resin composition according to the present invention includes at least one epoxy resin and at least two curing agents. The resin composition according to the present invention is a thermosetting resin composition. In the resin composition according to the present invention, the at least two curing agents include an active ester curing agent. Included in 100% by weight of all the curing agents in the resin composition according to the present invention of the total weight% of nitrogen atoms contained in 100% by weight of all the epoxy resins in the resin composition according to the present invention. The ratio of the total number of nitrogen atoms to the total weight% (total weight% of nitrogen atoms contained in 100% by weight of all epoxy resins / total weight% of nitrogen atoms contained in 100% by weight of all curing agents) 1/3 or more and 1 or less.

  In this invention, since the structure mentioned above is provided, the adhesiveness of the hardened | cured material after hardening and a conductor part can be improved, and a residual smear can be decreased at the time of via | veer processing. In the present invention, it is possible to achieve both high adhesion between the cured product and the conductor portion and suppression of remaining smear during via processing. By increasing the adhesion between the cured product and the conductor part after curing, floating and peeling can be suppressed, and the occurrence of an abnormal phenomenon called haloing can be suppressed. Further, in the present invention, the dielectric loss tangent can be lowered.

  Specifically, by using an epoxy resin and an active ester curing agent in a curing system, generation of a highly polar secondary hydroxyl group derived from an epoxy resin generated in a resin matrix in a conventional curing system such as a phenol curing agent. By suppressing, the dielectric loss tangent is reduced. However, the low polarity of this low-polarity resin results in insufficient adhesion to the copper of the conductor layer, and it is difficult to remove via bottom residue (smear) during laser via formation for conductor interlayer connection. To do.

  Therefore, by introducing nitrogen atoms with high affinity to copper directly into the resin matrix, specifically by prescribing a predetermined ratio as a curing agent containing nitrogen atoms, adhesion with copper can be improved. Can be improved.

  In addition, by prescribing a predetermined proportion of epoxy resin containing nitrogen atoms, a small amount of polar sites can be created by nitrogen atoms locally incorporated as the resin matrix skeleton, and this site becomes the origin of desmear and smears at the bottom of the via. Can be prevented from remaining.

  When the above ratio (total weight% of nitrogen atoms contained in 100% by weight of all epoxy resins / total weight% of nitrogen atoms contained in 100% by weight of all curing agents) is less than 1/3, The dielectric loss tangent of the cured product tends to be high, the polar sites increase too much, and the surface roughness of the surface of the cured product increases. When the above ratio (total weight% of nitrogen atoms contained in 100% by weight of all epoxy resins / total weight% of nitrogen atoms contained in 100% by weight of all curing agents) exceeds 1, smear remains. It becomes easy to do.

  The resin composition according to the present invention may contain only one kind of epoxy resin, or may contain two or more kinds. The at least one epoxy resin may contain only an epoxy resin having a nitrogen atom, or may contain an epoxy resin having a nitrogen atom and an epoxy resin not having a nitrogen atom.

  The at least two kinds of curing agents may include only a curing agent having a nitrogen atom, or may include a curing agent having a nitrogen atom and a curing agent not having a nitrogen atom. The said hardening | curing agent may contain only active ester hardening | curing agent, and may contain active ester hardening | curing agent and hardening | curing agents other than active ester. The curing agent may contain at least two active ester curing agents. The active ester curing agent may be an active ester curing agent having a nitrogen atom or an active ester curing agent having no nitrogen atom. The active ester curing agent may include only an active ester curing agent having a nitrogen atom, or may include only an active ester curing agent having no nitrogen atom, and an active ester curing agent having a nitrogen atom; And an active ester curing agent having no nitrogen atom. The curing agent may include an active ester curing agent having a nitrogen atom and a curing agent having a nitrogen atom other than the active ester curing agent, other than the active ester curing agent having a nitrogen atom and the active ester curing agent. And a curing agent having no nitrogen atom, and an active ester curing agent having no nitrogen atom, and a curing agent having a nitrogen atom other than the active ester curing agent. The curing agent preferably includes an active ester curing agent having no nitrogen atom and a curing agent having a nitrogen atom other than the active ester curing agent.

  The total weight% of nitrogen atoms contained in 100% by weight of all the curing agents in the resin composition according to the present invention is preferably 0.5% by weight or more, more preferably 1% by weight or more, preferably 10%. % By weight or less, more preferably 5% by weight or less. When the total weight% of nitrogen atoms contained in 100% by weight of the curing agent is equal to or higher than the lower limit, the adhesion between the cured product part and the conductor part is further enhanced, and floating and peeling are less likely to occur. , Haloing is more difficult to occur. When the total weight% of nitrogen atoms contained in 100% by weight of the curing agent is not more than the above upper limit, the dielectric loss tangent is further lowered and the surface roughness of the surface of the cured product is further reduced.

  Insulating layers such as printed wiring boards are often required to have a low dielectric loss tangent. In the resin composition according to the present invention, the dielectric loss tangent of the cured product can be lowered. The dielectric loss tangent at a frequency of 5.8 GHz of the cured product obtained by curing the resin composition according to the present invention at 150 ° C. or more for 1 hour or more is preferably 0.008 or less, more preferably 0.007 or less, and still more preferably 0.8. 006 or less. The dielectric loss tangent at a frequency of 10 GHz of a cured product obtained by curing the resin composition according to the present invention at 150 ° C. or more for 0.5 hour or more is preferably 0.008 or less, more preferably 0.007 or less, and still more preferably 0.8. 006 or less.

  There is a risk that the conductor layer (copper) of the printed wiring board is oxidized when the thermosetting resin that is the insulating layer is cured, and the oxidized copper is weak against an etching solution (acid) and is easily scraped during etching. For example, even in a conductor layer coated with a resin, the portion of the conductor in contact with the resin tends to be oxidized, leading to haloing or the like in a laser via process or the like. For this reason, it is desirable to reduce oxidation even a little. In a specific aspect of the resin composition according to the present invention, the thermosetting resin composition may be cured in an environment where the resin composition is not exposed to air.

  Examples of the environment that is not exposed to air include an environment of an inert gas such as argon or nitrogen, or an environment where the resin surface is covered with a resin film such as PET. Both can be combined in the above environment.

  The resin composition according to the present invention can be suitably used for insulation sealing of electronic parts, multilayer printed wiring boards such as mother boards, build-up wiring boards such as IC packages, and the like. Especially, the resin composition concerning this invention can be used suitably for a buildup wiring board.

  Hereinafter, the detail of each component used for the resin composition which concerns on this invention is demonstrated.

[Epoxy resin]
The resin composition includes at least one curing agent.

  The epoxy resin contained in the resin composition is not particularly limited. A conventionally well-known epoxy resin can be used as this epoxy resin. The epoxy resin refers to an organic compound having at least one epoxy group. As for an epoxy resin, only 1 type may be used and 2 or more types may be used together.

  Examples of the epoxy resin include isocyanuric acid skeleton epoxy resin, p-aminophenol type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, biphenyl type epoxy resin, and biphenyl. Novolac type epoxy resin, biphenol type epoxy resin, naphthalene type epoxy resin, fluorene type epoxy resin, phenol aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, dicyclopentadiene type epoxy resin, anthracene type epoxy resin, epoxy resin having adamantane skeleton , Epoxy resins having a tricyclodecane skeleton, and epoxy resins having a triazine nucleus in the skeleton.

  From the viewpoint of effectively enhancing the adhesion between the cured product and the conductor portion and further suppressing smear remaining during via processing, the at least one epoxy resin contains an epoxy resin having an epoxy equivalent of 120 or less. Is preferred.

  In 100% by weight of the total solid content of the resin composition, the content of the epoxy resin is preferably 10% by weight or more, more preferably 15% by weight or more, preferably 95% by weight or less, more preferably 90% by weight or less. The “solid content” refers to the total of the epoxy resin, the curing agent, and other solid content blended as necessary. “Solid content” refers to a non-volatile component that does not volatilize during molding or heating.

  The content of the epoxy resin having an epoxy equivalent of 120 or less in the total 100% by weight of the epoxy resin is preferably 5% by weight or more, more preferably 10% by weight or more, preferably 30% by weight or less, more preferably 20% by weight. % Or less.

[Curing agent]
The resin composition contains at least two kinds of curing agents in order to cure the epoxy resin.

  Examples of the curing agent include a cyanate ester compound and a cyanate ester compound prepolymer (cyanate ester curing agent), a phenol compound (phenol curing agent), an amine compound (amine curing agent), a thiol compound (thiol curing agent), an imidazole compound, Examples include phosphine compounds, acid anhydrides, active ester compounds (active ester curing agents), and dicyandiamide.

  In the present invention, an active ester curing agent is used as the curing agent. That is, the at least two kinds of curing agents include an active ester curing agent.

  The total content of the curing agent is preferably 80 parts by weight or more, more preferably 90 parts by weight or more, preferably 120 parts by weight or less, more preferably 110 parts by weight or less, with respect to 100 parts by weight of the total epoxy resin. It is.

  From the viewpoint of effectively enhancing the adhesion between the cured product and the conductor portion, and further suppressing the residual smear during via processing, the content of the active ester curing agent in the total of 100% by weight of the at least two curing agents. Is preferably 5% by weight or more, more preferably 10% by weight or more, preferably 95% by weight or less, more preferably 90% by weight or less.

  The at least two curing agents preferably include an aminotriazine-modified phenol curing agent or an aminotriazine-modified cresol curing agent as a curing agent other than the active ester curing agent. In this case, only one of the aminotriazine-modified phenol curing agent and the aminotriazine-modified cresol curing agent may be used, or both may be used.

  From the viewpoint of effectively increasing the adhesion between the cured product and the conductor portion and further suppressing the remaining smear during via processing, an aminotriazine-modified phenol curing agent and a total of 100% by weight of the at least two curing agents described above and The total content of the aminotriazine-modified cresol curing agent is preferably 5% by weight or more, more preferably 10% by weight or more, preferably 95% by weight or less, more preferably 90% by weight or less.

  From the viewpoint of effectively increasing the adhesion between the cured product and the conductor portion and further suppressing the residual smear during via processing, the total number of reactive groups of all the curing agents in the resin composition, Ratio of the above aminotriazine-modified phenol curing agent and aminotriazine-modified cresol curing agent to the total number of reactive groups in the resin composition (total number of reactive groups of all curing agents / aminotriazine-modified phenol curing agent and aminotriazine The total number of reactive groups of the modified cresol curing agent is preferably 2.5 or more, more preferably 3.3 or more, preferably 10 or less, more preferably 6.7 or less. The reactive group means an active ester group, a hydroxyl group, a cyanate group, and the like.

[Thermoplastic resin]
The resin composition preferably contains a thermoplastic resin. Examples of the thermoplastic resin include polyvinyl acetal resin and phenoxy resin. As for the said thermoplastic resin, only 1 type may be used and 2 or more types may be used together.

  From the viewpoint of effectively lowering the dielectric loss tangent and effectively improving the adhesion between the cured product and the conductor portion, the thermoplastic resin is preferably a phenoxy resin. By using the phenoxy resin, deterioration of the embedding property of the resin film with respect to the holes or irregularities of the circuit board and non-uniformity of the inorganic filler can be suppressed. In addition, since the melt viscosity can be adjusted by using a phenoxy resin, the dispersibility of the inorganic filler is improved, and the resin film is difficult to wet and spread in an unintended region during the curing process. The phenoxy resin contained in the resin composition is not particularly limited. A conventionally known phenoxy resin can be used as the phenoxy resin. As for the said phenoxy resin, only 1 type may be used and 2 or more types may be used together.

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

  Examples of commercially available phenoxy resins include “YP50”, “YP55” and “YP70” manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., and “1256B40”, “4250”, “4256H40” manufactured by Mitsubishi Chemical Corporation, “ 4275 "," YX6954BH30 "," YX8100BH30 ", and the like.

  From the viewpoint of obtaining a more excellent resin film due to storage stability, the weight average molecular weight of the thermoplastic resin and the phenoxy resin is preferably 5,000 or more, more preferably 10,000 or more, preferably 100,000 or less, more preferably 50,000 or less. It is.

  The weight average molecular weights of the thermoplastic resin and the phenoxy resin indicate the weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

  Content of the said thermoplastic resin and the said phenoxy resin is not specifically limited. In the total solid content of 100% by weight contained in the resin composition according to the present invention, the content of the thermoplastic resin and the phenoxy resin is preferably 2% by weight or more, more preferably 4% by weight or more, preferably 15% by weight. Hereinafter, it is more preferably 10% by weight or less. When the contents of the thermoplastic resin and the phenoxy resin are not less than the above lower limit and not more than the above upper limit, the embedding property of the resin film with respect to the holes or irregularities of the circuit board becomes good. When the content of the thermoplastic resin and the phenoxy resin is equal to or more than the lower limit, the resin composition can be more easily formed into a film, and a better insulating layer can be obtained. When the content of the phenoxy resin is not more than the above upper limit, the thermal expansion coefficient of the cured product is further reduced. The surface roughness of the surface of the cured product is further reduced, and the adhesive strength between the cured product and the metal layer is further increased.

[Inorganic filler]
The resin composition preferably contains an inorganic filler. Use of the inorganic filler further reduces the dimensional change due to heat of the cured product. Furthermore, the surface roughness of the surface of the cured product is further reduced, and the adhesive strength between the cured product and the metal layer is further increased.

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

  The surface roughness of the cured product is reduced, the adhesive strength between the cured product and the metal layer is further increased, finer wiring is formed on the surface of the cured product, and better insulation reliability is achieved by the cured product. From the viewpoint of imparting the above, the inorganic filler is preferably silica or alumina, more preferably silica, and still more preferably fused silica. By using silica, the coefficient of thermal expansion of the cured product is further reduced, the surface roughness of the surface of the cured product is effectively reduced, and the adhesive strength between the cured product and the metal layer is effectively increased. The shape of silica is preferably spherical.

  Regardless of the curing environment, the inorganic filler is spherical silica from the viewpoint of promoting the curing of the resin, effectively increasing the glass transition temperature of the cured product, and effectively reducing the thermal linear expansion coefficient of the cured product. It is preferable.

  The average particle size of the inorganic filler is preferably 10 nm or more, more preferably 50 nm or more, further preferably 150 nm or more, preferably 20 μm or less, more preferably 10 μm or less, still more preferably 5 μm or less, and particularly preferably 1 μm or less. is there. When the average particle size of the inorganic filler is not less than the above lower limit and not more than the above upper limit, the size of the holes formed by the roughening treatment or the like becomes fine, and the number of holes increases. As a result, the adhesive strength between the cured product and the metal layer is further increased.

  A median diameter (d50) value of 50% is employed as the average particle diameter of the inorganic filler. The average particle size can be measured using a laser diffraction / scattering particle size distribution measuring apparatus.

  Each of the inorganic fillers is preferably spherical, and more preferably spherical silica. In this case, the surface roughness of the surface of the cured product is effectively reduced, and the adhesive strength between the insulating layer and the metal layer is effectively increased. When each of the inorganic fillers is spherical, the aspect ratio of each of the inorganic fillers is preferably 2 or less, more preferably 1.5 or less.

  The inorganic filler is preferably surface-treated, and more preferably surface-treated with a silane coupling agent. Thereby, the surface roughness of the surface of the roughened cured product is further reduced, the adhesive strength between the cured product and the metal layer is further increased, and finer wiring is formed on the surface of the cured product, and more Better inter-wiring insulation reliability and interlayer insulation reliability can be imparted to the cured product.

  Examples of the coupling agent include silane coupling agents, titanate coupling agents, and aluminum coupling agents. Examples of the silane coupling agent include methacryl silane, acrylic silane, amino silane, imidazole silane, vinyl silane, and epoxy silane.

  In the total solid content of 100% by weight contained in the resin composition, the content of the inorganic filler is preferably 25% by weight or more, more preferably 30% by weight or more, still more preferably 40% by weight or more, and particularly preferably 50%. % By weight or more, preferably 99% by weight or less, more preferably 85% by weight or less, still more preferably 80% by weight or less, and particularly preferably 75% by weight or less. When the total content of the inorganic filler is not less than the above lower limit and not more than the above upper limit, the surface roughness of the surface of the cured product is further reduced, and the adhesive strength between the cured product and the metal layer is further increased, In addition, finer wiring is formed on the surface of the cured product, and at the same time, with this amount of inorganic filler, it is possible to lower the thermal expansion coefficient of the cured product as well as metal copper.

[Curing accelerator]
The resin composition preferably contains a curing accelerator. By using the curing accelerator, the curing rate is further increased. By rapidly curing the resin film, the crosslinked structure in the cured product becomes uniform, the number of unreacted functional groups decreases, and as a result, the crosslinking density increases. The said hardening accelerator is not specifically limited, A conventionally well-known hardening accelerator can be used. As for the said hardening accelerator, only 1 type may be used and 2 or more types may be used together.

  Examples of the curing accelerator include imidazole compounds, phosphorus compounds, amine compounds, and organometallic compounds.

  Examples of the imidazole compound include 2-undecylimidazole, 2-heptadecylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl- 2-methylimidazole, 1-benzyl-2-phenylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-un Decylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2 ′ -Methyl Midazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-undecylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6 [2′-Ethyl-4′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine Isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4-methyl-5-dihydroxymethylimidazole Can be mentioned.

  Examples of the phosphorus compound include triphenylphosphine.

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

  Examples of the organometallic compound include zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, bisacetylacetonate cobalt (II), and trisacetylacetonate cobalt (III).

  The content of the curing accelerator is not particularly limited. In 100% by weight of the total solid content contained in the resin composition, the content of the curing accelerator is preferably 0.01% by weight or more, more preferably 0.9% by weight or more, preferably 3.0% by weight. % Or less, more preferably 1.8% by weight or less. When the content of the curing accelerator is not less than the above lower limit and not more than the above upper limit, the resin film is efficiently cured. If content of the said hardening accelerator is a more preferable range, the storage stability of a resin composition will become still higher and a much better hardened | cured material will be obtained.

[solvent]
The resin composition does not contain or contains a solvent. By using the solvent, the viscosity of the resin composition can be controlled within a suitable range, and the coatability of the resin composition can be improved. Moreover, the said solvent may be used in order to obtain the slurry containing the said inorganic filler. As for the said solvent, only 1 type may be used and 2 or more types may be used together.

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

  Most of the solvent is preferably removed when the resin composition is formed into a film. Therefore, the boiling point of the solvent is preferably 200 ° C. or lower, more preferably 180 ° C. or lower. The content of the solvent in the resin composition is not particularly limited. The content of the solvent can be appropriately changed in consideration of the coating property of the resin composition.

[Other ingredients]
For the purpose of improving impact resistance, heat resistance, resin compatibility, workability, etc., the resin composition includes a leveling agent, a flame retardant, a coupling agent, a colorant, an antioxidant, an ultraviolet degradation inhibitor, An antifoaming agent, a thickener, a thixotropic agent, and other thermosetting resins other than the above-described epoxy resins may be added.

  Examples of the coupling agent include silane coupling agents, titanium coupling agents, and aluminum coupling agents. Examples of the silane coupling agent include vinyl silane, amino silane, imidazole silane, and epoxy silane.

  Examples of the other thermosetting resins include polyphenylene ether resins, divinyl benzyl ether resins, polyarylate resins, diallyl phthalate resins, polyimide resins, benzoxazine resins, benzoxazole resins, bismaleimide resins, and acrylate resins.

(Resin film and laminated film)
The resin composition described above may be used as a resin film by forming it into a film.

  From the viewpoint of more uniformly controlling the degree of cure of the resin film, the thickness of the resin film is preferably 5 μm or more, and preferably 200 μm or less.

  As a method for forming the resin composition into a film, for example, an extrusion molding method is used in which the resin composition is melt-kneaded using an extruder, extruded, and then formed into a film using a T-die or a circular die. And a casting molding method in which a resin composition containing a solvent is cast to form a film, and other conventionally known film molding methods. Especially, since it can respond to thickness reduction, the extrusion molding method or the casting molding method is preferable. The film includes a sheet.

  The resin composition which is a B stage film can be obtained by forming the resin composition into a film and drying it by heating at 90 to 200 ° C. for 1 to 180 minutes, for example, so that curing by heat does not proceed excessively. .

  The film-like resin composition that can be obtained by the drying process as described above is referred to as a B-stage film. The B-stage film is a semi-cured product in a semi-cured state. The semi-cured product is not completely cured and curing can proceed further.

  The resin film may not be a prepreg. When the resin film is not a prepreg, migration does not occur along a glass cloth or the like. Further, when laminating or precuring the resin film, the surface is not uneven due to the glass cloth. Moreover, by setting it as the resin film which does not contain a prepreg, the dimensional change by the heat | fever of hardened | cured material becomes small, shape retention property becomes high, and a semiadditive process suitability becomes high.

  The said resin composition can be used suitably in order to form a laminated film provided with metal foil or a base material, and the resin film laminated | stacked on the surface of this metal foil or base material. The resin film in the laminated film is formed from the resin composition. The metal foil is preferably a copper foil.

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

  When the resin composition and the resin film are used as an insulating layer of a circuit, the thickness of the insulating layer formed of the resin composition or the resin film is equal to or greater than the thickness of the conductor layer (metal layer) forming the circuit. It is preferable that The thickness of the insulating layer is preferably 5 μm or more, and preferably 200 μm or less.

(Printed wiring board)
The resin composition and the resin film are suitably used for forming an insulating layer in a printed wiring board.

  The printed wiring board can be obtained, for example, by heat-pressing the resin film.

  A metal foil can be laminated on one side or both sides of the resin film. The method for laminating the resin film and the metal foil is not particularly limited, and a known method can be used. For example, the resin film can be laminated on the metal foil using an apparatus such as a parallel plate press or a roll laminator while applying pressure while heating or without heating.

(Copper-clad laminate and multilayer board)
The resin composition and the resin film are preferably used for obtaining a copper-clad laminate. An example of the copper-clad laminate includes a copper-clad laminate including a copper foil and a resin film laminated on one surface of the copper foil. The resin film of this copper-clad laminate is formed from the resin composition.

  The thickness of the copper foil of the copper-clad laminate is not particularly limited. The thickness of the copper foil is preferably in the range of 1 to 50 μm. Moreover, in order to raise the adhesive strength of the insulating layer which hardened the said resin film, and copper foil, it is preferable that the said copper foil has a fine unevenness | corrugation on the surface. The method for forming the unevenness is not particularly limited. Examples of the method for forming the unevenness include a formation method by treatment using a known chemical solution.

  The resin composition and the resin film are preferably used for obtaining a multilayer substrate. As an example of the multilayer substrate, a multilayer substrate including a circuit substrate and an insulating layer stacked on the surface of the circuit substrate can be given. The insulating layer of this multilayer substrate is formed of the resin film using a resin film obtained by forming the resin composition into a film. Moreover, the insulating layer of the multilayer substrate may be formed of the resin film of the laminated film using a laminated film. The insulating layer is preferably laminated on the surface of the circuit board on which the circuit is provided. Part of the insulating layer is preferably embedded between the circuits.

  In the multilayer substrate, it is preferable that the surface of the insulating layer opposite to the surface on which the circuit substrate is laminated is roughened.

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

  Moreover, it is preferable that the said multilayer substrate is further equipped with the copper plating layer laminated | stacked on the surface by which the roughening process of the said insulating layer was carried out.

  As another example of the multilayer board, the circuit board, the insulating layer laminated on the surface of the circuit board, and the surface of the insulating layer opposite to the surface on which the circuit board is laminated are laminated. And a multilayer substrate provided with copper foil. The insulating layer and the copper foil are formed by curing the resin film using a copper-clad laminate including a copper foil and a resin film laminated on one surface of the copper foil. preferable. Furthermore, it is preferable that the copper foil is etched and is a copper circuit.

  Another example of the multilayer substrate is a multilayer substrate including a circuit board and a plurality of insulating layers stacked on the surface of the circuit board. At least one of the plurality of insulating layers arranged on the circuit board is formed using a resin film obtained by forming the resin composition into a film. It is preferable that the multilayer substrate further includes a circuit laminated on at least one surface of the insulating layer formed using the resin film.

  In FIG. 1, the multilayer substrate using the resin composition which concerns on one Embodiment of this invention is typically shown with a partial notch front sectional drawing.

  In the multilayer substrate 11 shown in FIG. 1, a plurality of insulating layers 13 to 16 are laminated on the upper surface 12 a of the circuit substrate 12. Insulating layers 13-16 are hardened material layers. A metal layer 17 is formed in a partial region of the upper surface 12 a of the circuit board 12. Among the plurality of insulating layers 13 to 16, the metal layer 17 is formed in a partial region of the upper surface of the insulating layers 13 to 15 other than the insulating layer 16 located on the outer surface opposite to the circuit board 12 side. Has been. The metal layer 17 is a circuit. Metal layers 17 are respectively disposed between the circuit board 12 and the insulating layer 13 and between the stacked insulating layers 13 to 16. The lower metal layer 17 and the upper metal layer 17 are connected to each other by at least one of via hole connection and through hole connection (not shown).

  In the multilayer board | substrate 11, the insulating layers 13-16 are formed using the resin film which shape | molded the resin composition which concerns on this invention in the film form. In this embodiment, since the surfaces of the insulating layers 13 to 16 are roughened, fine holes (not shown) are formed on the surfaces of the insulating layers 13 to 16. Further, the metal layer 17 reaches the inside of the fine hole. Moreover, in the multilayer substrate 11, the width direction dimension (L) of the metal layer 17 and the width direction dimension (S) of the part in which the metal layer 17 is not formed can be made small. In the multilayer substrate 11, good insulation reliability is imparted between an upper metal layer and a lower metal layer that are not connected by via-hole connection and through-hole connection (not shown).

(Roughening treatment and swelling treatment)
It is preferable that the said resin composition is used in order to obtain the hardened | cured material by which a roughening process or a desmear process is carried out. The cured product includes a precured product that can be further cured.

  In order to form fine irregularities on the surface of the cured product obtained by precuring the resin composition, the cured product is preferably roughened. Prior to the roughening treatment, the cured product is preferably subjected to a swelling treatment. The cured product is preferably subjected to a swelling treatment after preliminary curing and before the roughening treatment, and is further cured after the roughening treatment. However, the cured product is not necessarily subjected to the swelling treatment.

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

  For the roughening treatment, for example, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfuric acid compound is used. These chemical oxidizers are used as an aqueous solution or an organic solvent dispersion after water or an organic solvent is added. The roughening liquid used for the roughening treatment generally contains an alkali as a pH adjuster or the like. The roughening solution preferably contains sodium hydroxide.

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

  The method for the roughening treatment is not particularly limited. As a method of the said roughening process, 30-90 g / L permanganic acid or a permanganate solution and 30-90 g / L sodium hydroxide solution are used, for example, process temperature 30-85 degreeC and 1-30 minutes. A method of treating a cured product under conditions is preferable. The roughening treatment temperature is preferably in the range of 50 to 85 ° C. The number of times of the roughening treatment is preferably once or twice.

  The arithmetic average roughness Ra of the surface of the cured product is preferably 50 nm or more, preferably 350 nm or less, more preferably less than 200 nm, still more preferably less than 100 nm. In this case, the adhesive strength between the cured product and the metal layer or wiring is increased, and further finer wiring is formed on the surface of the insulating layer.

(Desmear treatment)
A through-hole may be formed in the hardened | cured material obtained by precuring the said resin composition. In the multilayer substrate or the like, a via or a through hole is formed as a through hole. For example, the via can be formed by irradiation with a laser such as a CO ₂ laser. The diameter of the via is not particularly limited, but is about 60 to 80 μm. Due to the formation of the through hole, a smear that is a resin residue derived from the resin component contained in the cured product may be formed at the bottom of the via. However, the use of the resin composition can reduce the residual smear.

  In order to remove the smear, the surface of the cured product is preferably desmeared. The desmear process may also serve as a roughening process.

  In the desmear treatment, for example, a chemical oxidant such as a manganese compound, a chromium compound, or a persulfate compound is used in the same manner as the roughening treatment. These chemical oxidizers are used as an aqueous solution or an organic solvent dispersion after water or an organic solvent is added. The desmear treatment liquid used for the desmear treatment generally contains an alkali. The desmear treatment liquid preferably contains sodium hydroxide.

  The method for the desmear treatment is not particularly limited. As a method for the desmear treatment, for example, using a 30 to 90 g / L permanganate or permanganate solution and a 30 to 90 g / L sodium hydroxide solution, a treatment temperature of 30 to 85 ° C. and a condition of 1 to 30 minutes And the method of processing hardened | cured material once or twice is suitable. It is preferable that the temperature of the said desmear process exists in the range of 50-85 degreeC.

  By using the resin composition, the surface roughness of the surface of the cured product that has been desmeared is sufficiently reduced.

  Hereinafter, the present invention will be specifically described by giving examples and comparative examples. The present invention is not limited to the following examples.

  The following ingredients were used.

(Epoxy resin)
Epoxy resin 1: Isocyanuric acid skeleton epoxy resin (“TEPIC-SP” manufactured by Nissan Chemical Industries, epoxy equivalent 100 g / eq, nitrogen atom content 19% by weight)
Epoxy resin 2: p-aminophenol type epoxy resin ("630" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 96g / eq, nitrogen atom content 5% by weight)
Epoxy resin 3: bisphenol A type epoxy resin (“828EL” manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 186 g / eq)
Epoxy resin 4: Naphthalene type epoxy resin (“HP4032D” manufactured by DIC, epoxy equivalent 152 g / eq)
Epoxy resin 5: Naphthalene type epoxy resin (“HP4700” manufactured by DIC, epoxy equivalent 165 g / eq)
Epoxy resin 6: biphenyl type epoxy resin (“NC3000” manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 276 g / eq)

(Curing agent)
Active ester curing agent 1: Naphthalene skeleton active ester resin (“EXB9416” manufactured by DIC, ester equivalent 330 g / eq)
Active ester curing agent 2: Active ester resin with dicyclopentadiene skeleton (“HPC8000” manufactured by DIC, ester equivalent 223 g / eq)
ATN curing agent: aminotriazine-modified phenol novolak resin (“LA1356” manufactured by DIC, hydroxyl group equivalent: 146 g / eq, nitrogen atom content: 18% by weight)
ATCN curing agent: aminotriazine-modified cresol novolak resin (“LA3018” manufactured by DIC, hydroxyl group equivalent 151 g / eq, nitrogen atom content 19% by weight)

(Curing accelerator)
2-Ethyl-4-methylimidazole (“2E4MZ” manufactured by Shikoku Kasei Kogyo Co., Ltd.)
4-Dimethylaminopyridine (Wako Pure Chemical Industries, Ltd.)

(Inorganic filler)
Average particle size 0.5 μm silica (“SO-C2” manufactured by Admatechs, surface treatment is aminophenylsilane treatment (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.))
Silica with an average particle size of 1.0 μm (“SO-C4” manufactured by Admatechs Co., Ltd., surface treatment is aminophenylsilane treatment (“KBM573” manufactured by Shin-Etsu Chemical Co., Ltd.))

(Thermoplastic resin)
Phenoxy resin (bisphenolacetophenone skeleton phenoxy resin, solid content 30% by weight: “YX6954” manufactured by Mitsubishi Chemical Corporation)

(Solvent) * Since it is removed by drying, it is not listed in Table 1. Cyclohexanone

(Examples 1-8 and Comparative Examples 1-5)
Using the blending components shown in Table 1 below in the blending amounts shown in Table 1 below, each blending was performed according to the following procedure.

  Silica was slurried with a solvent, an epoxy resin was added, and the mixture was stirred for 60 minutes at 1200 rpm using a stirrer, and it was confirmed that there was no undissolved material. Then, the hardening | curing agent was added and it stirred at 1200 rpm for 60 minutes, and it confirmed that the undissolved material was lose | eliminated. Thereafter, a phenoxy resin and a curing accelerator were added and stirred at 1200 rpm for 30 minutes to obtain a resin composition (resin varnish).

  Next, a release-treated transparent polyethylene terephthalate (PET) film (“PET5011 550” manufactured by Lintec Corporation, thickness 50 μm) was prepared. The obtained varnish was coated on the release-treated surface of this PET film using an applicator so that the thickness after drying was 40 μm, dried in a gear oven at 100 ° C. for 1 minute, An uncured resin film (B stage film) having a width of 200 mm and a thickness of 40 μm was prepared. As a result, a laminated film of a PET film and a B stage film was obtained.

(Preparation of evaluation sample A (cured film))
The obtained B stage film was cured at 190 ° C. for 90 minutes in a gear oven to prepare a cured film having a length of 200 mm × width of 200 mm × thickness of 40 μm.

(Preparation of evaluation sample B (laminate))
1) Lamination step: A double-sided copper-clad laminate (18 μm thick copper foil on each side, 0.7 mm board thickness, 100 mm × 100 mm board size, “MCL-E679FG” manufactured by Hitachi Chemical Co., Ltd.) was prepared. Both surfaces of the copper foil surface of this double-sided copper-clad laminate were immersed in “Cz8101” manufactured by MEC, and the surface of the copper foil was roughened. Using a “batch type vacuum laminator MVLP-500-IIA” manufactured by Meiki Seisakusho Co., Ltd. on both surfaces of the roughened copper clad laminate, the surface of the B stage film faces the copper clad laminate surface. Thus, a laminated structure was obtained. The laminating condition was such that the pressure was reduced to 30 hPa or less by reducing the pressure for 30 seconds, and then pressing was performed at 100 ° C. and a pressure of 0.8 MPa for 30 seconds.

  2) Film peeling process: In the copper clad laminate on which the B stage film was laminated, the PET films on both sides were peeled off.

  3) Curing step: The laminated plate was placed in a gear oven having an internal temperature of 180 ° C. for 30 minutes to cure the B stage film to form an insulating layer.

(Production of evaluation sample C (laminated body with copper foil))
After the step 2) of producing the evaluation sample B, a foil (thickness whose surface was etched by about 1 μm) was obtained by subjecting the shiny surface of the copper foil (thickness 35 μm, manufactured by Mitsui Kinzoku Co., Ltd.) to Cz treatment (“Cz8101” manufactured by MEC). Were pasted together.

  Further, the substrate with copper foil was heat-treated at 190 ° C. for 90 minutes in a gear oven, and an evaluation sample C was obtained.

(Evaluation)
(1) Evaluation of base copper peel strength (copper foil peel strength) Cut into a strip shape so as to be 1 cm wide on the copper foil surface side of the laminate of evaluation sample C. The substrate was set on a 90 ° peel tester (“TE-3001” manufactured by Tester Sangyo Co., Ltd.), the edge of the cut copper foil was picked up with a gripping tool, the copper foil was peeled off by 20 mm, and the peel strength was measured. .

(2) Evaluation of laser desmear For evaluation sample B, using a CO ₂ laser (“LC-1K21” manufactured by Hitachi Via Mechanics Co., Ltd.), the diameter at the upper end is 60 μm and the diameter at the lower end (bottom) is 40 μm. (Through hole) was formed. Thus, the laminated body D by which the semi-cured material of the resin film was laminated | stacked on the laminated body, and the via | veer (through-hole) was formed in the semi-cured material of the resin film was obtained.

<Desmear treatment>
(A) Swelling treatment The obtained laminate B was placed in a swelling liquid at 80 ° C. (“Swelling dip securigant P” manufactured by Atotech Japan Co., Ltd.) and rocked for 10 minutes. Thereafter, it was washed with pure water.

(B) Permanganate treatment In 80 ° C potassium permanganate ("Concentrate Compact CP" manufactured by Atotech Japan) roughened aqueous solution, the laminate B after the swelling treatment was put and rocked for 20 minutes. Next, after processing for 2 minutes using the 25 degreeC washing | cleaning liquid ("Reduction securigant P" by Atotech Japan), it wash | cleaned with the pure water and the laminated body E was obtained.

  The bottom of the via of the laminate E was observed with a scanning electron microscope (SEM), and the maximum length of smear from the wall surface of the via bottom was measured. The removability of the residue at the bottom of the via was determined according to the following criteria.

[Judgment criteria for laser desmear (removability of via bottom residue)]
○: Maximum smear length is less than 3 μm Δ: Maximum smear length is 3 μm or more and less than 5 μm ×: Maximum smear length is 5 μm or more

(3) Evaluation of haloing Laminated body E was subjected to electroless copper plating and electrolytic copper plating, and the via portion was also filled with plating. Thereafter, heat treatment was performed at 190 ° C. for 90 minutes.

  Surface polishing was performed on the via-processed portion of the obtained substrate, and the copper plating and the resin layer on the via portion and its peripheral portion were removed just before the base copper.

  The polished substrate was observed at a magnification of 100 using a metal microscope (Olympus “STM6”), and the size of the ring (haloing) generated in the periphery of the via was measured. Helloing was judged according to the following criteria. The ring is a part where the insulating layer is floated and peeled off in the periphery of the via, and the haloing diameter is the outer diameter of the part where the floating and peeled off.

[Helloing criteria]
○○: Halo diameter is 60 μm or more and less than 120 μm ○: Hallowing diameter is 120 μm or more and less than 200 μm Δ: Hallowing diameter is 200 μm or more and less than 400 μm ×: Haloing diameter is 400 μm or more

(4) Evaluation of dielectric loss tangent Evaluation sample A was cut into a size of 2 mm in width and 80 mm in length, and 5 sheets were stacked to obtain a laminate having a thickness of 200 μm. About the obtained laminate, using a “cavity resonance perturbation method dielectric constant measuring device CP521” manufactured by Kanto Electronics Application Development Co., Ltd. and “network analyzer N5224A PNA” manufactured by Keysight Technology, Inc., to room temperature (23 ° C.) by a cavity resonance method. The dielectric loss tangent was measured at frequencies of 5.8 GHz and 10 GHz.

(5) Evaluation of average linear expansion coefficient Evaluation sample A was cut into a size of 3 mm x 25 mm. Using a thermomechanical analyzer (“EXSTAR TMA / SS6100” manufactured by SII Nano Technology), the cured product cut at 25 ° C. to 150 ° C. under the conditions of a tensile load of 33 mN and a heating rate of 5 ° C./min. The average linear expansion coefficient (ppm / ° C.) was calculated.

(6) Evaluation of Arithmetic Average Roughness Ra of Surface after Roughing For evaluation sample B, non-contact type surface roughness meter (manufactured by Beeco Instruments Inc. “ WYKO NT1100 ") was used to measure the surface roughness of the surface of the resin after desmearing with a VSI contact mode and a 50 × lens with a measurement range of 121 μm × 92 μm, and the arithmetic average roughness Ra was measured. The arithmetic average roughness Ra was measured at three measurement points selected at random, and the average value of the measurement values was adopted. The arithmetic average roughness is a value in JIS B0601-1994.

(7) Evaluation of copper plating peel strength The laminate F was cut into a strip shape so as to have a width of 1 cm on the copper plating surface side of the laminate G subjected to electroless copper plating and electrolytic copper plating. The substrate was set on a 90 ° peel tester, the end of the copper plating cut with a gripper was picked up, the copper plating was peeled off by 20 mm, and the peel strength was measured.

  The results are shown in Table 1 below.

DESCRIPTION OF SYMBOLS 11 ... Multilayer substrate 12 ... Circuit board 12a ... Upper surface 13-16 ... Insulating layer 17 ... Metal layer (wiring)

Claims (7)

Comprising at least one epoxy resin and at least two curing agents;
The at least two curing agents comprise an active ester curing agent;
The total weight% of nitrogen atoms contained in 100% by weight of all the curing agents in the resin composition of the total weight% of nitrogen atoms contained in 100% by weight of all the epoxy resins in the resin composition The resin composition whose ratio to is 1/3 or more and 1 or less.   The resin composition according to claim 1, wherein the at least two kinds of curing agents include an aminotriazine-modified phenol curing agent or an aminotriazine-modified cresol curing agent as a curing agent other than the active ester curing agent. The ratio of the total number of reactive groups of all the curing agents in the resin composition to the total number of reactive groups of the aminotriazine-modified phenol curing agent and aminotriazine-modified cresol curing agent in the resin composition is 2 The resin composition according to claim 2 , which is 5 or more and 10 or less.   The resin composition of any one of Claims 1-3 whose dielectric loss tangent in the frequency 5.8GHz of the hardened | cured material hardened | cured at 150 degreeC or more for 0.5 hour or more is 0.007 or less.   The resin composition according to any one of claims 1 to 4, wherein the at least one epoxy resin includes an epoxy resin having an epoxy equivalent of 120 or less.   The resin composition according to any one of claims 1 to 5, wherein curing is performed in an environment where the curing is not exposed to air.   The resin composition of any one of Claims 1-6 which is an insulating material used for a buildup wiring board.

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