JP2012211269A - Precured product, roughened precured product and laminate - Google Patents

Abstract

The present invention provides a precured product that can reduce the surface roughness of the roughened surface of the roughened precured product and can increase the adhesive strength between the cured product and the metal layer.
A precured product 1 according to the present invention is obtained by proceeding with curing of an epoxy resin material. Pre-cured product 1 has a first main surface 1a and a second main surface 1b to be roughened. The epoxy resin material includes an epoxy resin, a curing agent, and silica 2. Silica 2 includes a first small particle size silica 2A having a particle size of 0.01 μm or more and less than 0.5 μm, and a second large particle size silica 2B having a particle size of 0.5 μm or more and 20 μm or less. Including. In the preliminary-cured product 1, the first small particle size silica 2A and the second large particle size silica 2B are unevenly distributed. The preliminary-cured product 1 has a first region R1 and a second region R2 in which the abundances of the first small particle size silica 2A and the second large particle size silica 2B are different.
[Selection] Figure 1

Description

  The present invention relates to a precured product obtained by advancing curing of an epoxy resin material using an epoxy resin material containing an epoxy resin, a curing agent, and silica, and a roughened preliminary material using the precured material. The present invention relates to a cured product and a laminate.

  Conventionally, various resin compositions have been used to obtain electronic components such as laminates and printed wiring boards. For example, in a multilayer printed wiring board, a resin composition is used in order to form an insulating layer for insulating inner layers or to form an insulating layer located in a surface layer portion.

  As an example of the resin composition, Patent Document 1 below discloses a resin composition containing an epoxy resin, a curing agent, a phenoxy resin, and an inorganic filler having an average particle diameter of 0.01 to 2 μm. Has been. Further, Patent Document 1 discloses a resin composition containing an epoxy resin, a curing agent, and an inorganic filler having an average particle diameter of 0.1 to 10 μm.

  In patent document 1, each layer of the multilayer film which has a laminated structure of two layers is formed using two types of above-mentioned different resin compositions. It is described that this multilayer film is satisfactorily embedded in a gap or the like provided on the substrate.

  Patent Document 2 below discloses a resin composition containing an epoxy resin, a curing agent, at least one of a phenoxy resin and a polyvinyl acetal resin, and a phosphorus-containing benzoxazine compound. In Patent Document 2, when a cured product obtained by curing a resin composition is roughened, the roughened surface exhibits high adhesion to the plated conductor even though the roughness of the roughened surface is relatively small. In addition, it is described that an insulating layer excellent in flame retardancy can be obtained.

JP 2008-302677 A WO2009 / 038166A1

  In patent document 1, since two types of resin compositions are prepared and the multilayer film is produced, there exists a problem that production of a multilayer film takes time and cost becomes high.

  Patent Document 2 describes that the roughness of the roughened surface is not sufficiently reduced, although it is described that the resin composition has the above composition to reduce the roughness.

  Moreover, in the multilayer film described in Patent Document 1 and the resin composition described in Patent Document 2, when a metal layer is formed by plating on the surface of a cured product obtained by curing these, the cured product, the metal layer, It may be difficult to sufficiently increase the adhesive strength.

  The object of the present invention is to reduce the surface roughness of the roughened surface of the roughened preliminary-cured product and to increase the adhesive strength between the cured product obtained by curing the roughened preliminary-cured product and the metal layer. It is to provide a precured material that can be prepared, and a roughened precured material and a laminate using the precured material.

  According to a wide aspect of the present invention, there is provided a pre-cured product obtained by advancing curing of an epoxy resin material, which has a first main surface and a second main surface, the first main surface The surface is a surface to be roughened, and the epoxy resin material contains an epoxy resin, a curing agent, and silica, and the content of all the silica in 100% by volume of the epoxy resin material is 40% by volume or more. The silica contains a first small particle size silica having a particle size of 0.01 μm or more and less than 0.5 μm, and a second large particle size silica having a particle size of 0.5 μm or more and 20 μm or less. In the precured material, the first small particle size silica and the second large particle size silica are unevenly distributed, and the surface on the first main surface side is a surface to be roughened. Of the 100% by volume of silica contained in the region having a thickness of 0.3 μm, the first The content of the silica having a large particle size of 2 is 5% by volume or less, and in the second region having a thickness of 1 μm connected to the first region, the content of all the silica is contained in 100% by volume of the second region. A precured product is provided, the amount of which is 20% by volume or less.

  In another specific aspect of the precured material according to the present invention, the minimum melt viscosity of the epoxy resin material before the precuring in the temperature range of 60 to 120 ° C. is 50 Pa · s or less.

  In another specific aspect of the preliminary-cured material according to the present invention, the epoxy resin material includes a cyanate ester resin as the curing agent.

  The roughened preliminary-cured material according to the present invention is a roughened preliminary-cured material obtained by roughening the first main surface of the preliminary-cured material configured according to the present invention.

  In a specific aspect of the roughened preliminary-cured material according to the present invention, the preliminary-cured material is swelled before the roughening treatment.

  The laminate according to the present invention includes a cured product obtained by curing a roughened preliminary cured product obtained by roughening the first main surface of the preliminary cured product configured according to the present invention, and the cured product. And a metal layer laminated on the roughened surface. The adhesive strength between the cured product and the metal layer is preferably 0.39 N / mm or more.

  The pre-cured product according to the present invention is a pre-cured product obtained by advancing curing of an epoxy resin material containing an epoxy resin, a curing agent, and silica, and all of the above silica in 100% by volume of the epoxy resin material. Is 40 volume% or more, and the silica has a first small particle size silica having a particle size of 0.01 μm or more and less than 0.5 μm, and a particle size of 0.5 μm or more and 20 μm or less. A surface containing a second large particle size silica, wherein the first small particle size silica and the second large particle size silica are unevenly distributed in the precured product, and further roughened. The content of the second large particle size silica is 5% by volume or less out of 100% by volume of all silica contained in the first region having a thickness of 0.3 μm on the surface portion on the first main surface side. And a second region having a thickness of 1 μm and continuous with the first region. In 100% by volume of the second region, the content of all the silicas is 20% by volume or less. Therefore, when the first main surface of the pre-cured product is roughened, the roughened pre-cured The surface roughness of the roughened surface of the object can be reduced. Furthermore, when the metal layer is formed on the surface of the cured product obtained by curing the roughened preliminary-cured product, the adhesive strength between the cured product and the metal layer can be increased.

FIG. 1 is a partially cutaway front sectional view schematically showing a precured product according to an embodiment of the present invention. FIG. 2 is a partially cutaway front sectional view schematically showing a laminate using a precured product according to an embodiment of the present invention.

  Hereinafter, the present invention will be clarified by describing specific embodiments and examples of the present invention with reference to the drawings.

  The precured material according to the present invention is a precured material obtained by allowing the epoxy resin material to cure. FIG. 1 is a front sectional view schematically showing a precured product according to an embodiment of the present invention.

  In the preliminary-cured product 1, an epoxy resin material in which the content of all the silica in 100% by volume of the epoxy resin material is 40% by volume or more is used in order to reduce the coefficient of thermal expansion.

  The precured material 1 shown in FIG. 1 is laminated on the upper surface 6 a of the lamination target member 6. Pre-cured product 1 has a first main surface 1a and a second main surface 1b. The first main surface 1a is a surface to be roughened. The second main surface 1 b is in contact with the upper surface 6 a of the stacking target member 6. The epoxy resin material for obtaining the precured material 1 includes an epoxy resin, a curing agent, and silica 2.

  Silica 2 includes a first small particle size silica 2A having a particle size of 0.01 μm or more and less than 0.5 μm, and a second large particle size silica 2B having a particle size of 0.5 μm or more and 20 μm or less. contains.

  In the preliminary-cured product 1, the first small particle size silica 2A and the second large particle size silica 2B are unevenly distributed. In the preliminary-cured product 1, the first small particle size silica 2A is unevenly distributed so as to be present on the first main surface 1a side which is a surface to be roughened. In the preliminary-cured product 1, the second large particle size silica 2B is unevenly distributed so as to be present on the second main surface 1b side.

  In the preliminary-cured product 1, the surface portion on the first main surface 1a side that is a surface to be roughened is included in a first region R1 having a thickness of 0.3 μm (a region above the upper broken line in FIG. 1). The content of the second large particle size silica 2B is 100% by volume or less of 5% by volume or less. All of the silica present in the first region R1 may be the first small particle size silica 2A.

  The smaller the amount of the second large particle diameter silica 2B in the first region R1, the better. The smaller the abundance of the second large particle size silica 2B in the first region R1, the more fine holes can be formed in the first main surface 1a when the first main surface 1a is roughened. The surface roughness of the treated surface can be further reduced. As a result, the adhesive strength between the cured product and the metal layer is also increased.

  In the second region having a thickness of 1 μm connected to the first region, the content of all silica in 100% by volume of the second region is 20% by volume or less. In 100% by volume of the second region, the content of all silica is preferably 5% by volume or less, more preferably 4% by volume or less, still more preferably 3% by volume or less, Particularly preferred is 0% by volume.

  The first region R1 and the second region R2 are in contact with each other. In the third region R3 (region below the broken line on the lower side in FIG. 1) on the second main surface 1b side connected to the second region R2, the total amount of the second large particle size silica 2B is 100% by volume. It is preferable that 80 volume% or more and 100 volume% or less exist. The entire amount of the second large particle size silica 2B may be present in the third region R3. In the third region R3, 85% by volume or more of 100% by volume of the second large particle size silica 2B is preferably present, and more preferably 90% by volume or more. Note that the second region R2 and the second region R3 are in contact with each other. The third region R3 is the remaining region excluding the first region R1 and the second region R2.

  The first small particle size silica 2A does not exist in the third region R3, or the first small particle size silica 2A exists in 70% by volume or less of the total amount of silica present in the third region. It is more preferable that it is present at 50% by volume or less. In this case, the abundance of the first small particle size silica 2A in the first region R1 can be increased. Therefore, when the first main surface 1a is roughened, fine holes can be formed in the first main surface 1a, and the surface roughness of the roughened surface can be further reduced. As a result, the adhesive strength between the cured product and the metal layer is also increased.

  When the first main surface 1a is roughened in the precured product 1, the first small particle size silica 2A and the second large particle size silica 2B are unevenly distributed as described above. In the first main surface 1a, fine holes from which the first small particle size silica 2A is detached are formed. As a result, the surface roughness of the roughened surface can be reduced. Furthermore, when a metal layer is formed on the surface of the cured product obtained by curing the roughened preliminary-cured product that has been subjected to the roughening treatment, the adhesive strength between the cured product and the metal layer can be increased. In addition, by forming a resin layer in which the presence of silica is clearly small, it is possible to improve electrical insulation in a region straddling the top and bottom of the resin layer.

  In addition, the thickness of the preliminary-cured product 1 is preferably 10 μm or more, more preferably 12 μm or more, preferably 50 μm or less, more preferably 40 μm or less.

  The minimum melt viscosity of the epoxy resin material before preliminary curing in the temperature range of 60 to 120 ° C. is preferably 70 Pa · s or less. The melt viscosity is preferably 1 Pa · s or more, more preferably 50 Pa · s or less, still more preferably less than 50 Pa · s, and particularly preferably 30 Pa · s or less. When the melt viscosity of the epoxy resin material is not less than the above lower limit and not more than the above upper limit, it becomes easy to obtain a precured product having a good layer structure at the time of a laminating step and press molding described later.

  The “melt viscosity” is a value measured using a rheometer under the condition where the epoxy resin material before preliminary curing is heated from 50 ° C. to 150 ° C. Examples of the rheometer include “AR-2000” manufactured by TA Instruments.

  Note that the first small particle size silica 2A and the second large particle size silica 2B are not unevenly distributed as described above by simply using the first small particle size silica 2A and the second large particle size silica 2B together. Sometimes. As a method of unevenly distributing the first small particle size silica 2A and the second large particle size silica 2B in the precured body 1 as described above, specifically, the laminating temperature described later is increased and the pressure is increased. The method of making small, the method of raising the temperature at the time of making it semi-cure, the method of mix | blending resin so that melt viscosity becomes small, etc. are mentioned.

  Hereinafter, the detail of each component contained in the said epoxy resin material is demonstrated.

(Epoxy resin material)
[Epoxy resin]
The epoxy resin contained in the epoxy resin material 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 bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, biphenyl novolac type epoxy resin, biphenol type epoxy resin, naphthalene type epoxy resin, and fluorene type epoxy resin. Phenol aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, dicyclopentadiene novolak type epoxy resin, anthracene type epoxy resin, epoxy resin having adamantane skeleton, epoxy resin having tricyclodecane skeleton, and epoxy having triazine nucleus in skeleton Examples thereof include resins.

  From the viewpoint of further reducing the surface roughness of the roughened surface of the roughened precured product and further increasing the adhesive strength between the cured product and the metal layer, the above epoxy resin is a biphenyl novolac type epoxy. A resin or a dicyclopentadiene type epoxy resin is preferred.

  The epoxy resin is preferably a bifunctional or higher functional epoxy resin, and more preferably a polyfunctional epoxy resin. Examples of the polyfunctional epoxy resin include a trifunctional alicyclic epoxy monomer (“Epolide GT301” manufactured by Union Carbide), and a trivalent epoxy resin having a triazine nucleus as a skeleton (“Denacol EX-” manufactured by Nagase ChemteX Corporation). 301 ”,“ TEPIC-S ”manufactured by Nissan Chemical Industries, Ltd.), biphenyl novolac type epoxy resin (“ NC3000H ”manufactured by Nippon Kayaku Co., Ltd.) as a polyfunctional epoxy resin, dicyclopentadiene novolac type epoxy resin (“ HP manufactured by DIC Corporation ”) -7200 "), bisphenol A novolac type epoxy resin (Mitsubishi Chemical" 157-S70 ") and the like.

  The melting point or softening point of the epoxy resin is preferably 50 ° C. or higher, more preferably 65 ° C. or higher, preferably 90 ° C. or lower, more preferably 85 ° C. or lower. When the melting point or softening point of the epoxy resin is not less than the above lower limit and not more than the above upper limit, in the precured product obtained by precuring the epoxy resin material on the lamination target member, the first small particle size silica and the second large particle The particle size silica is present in the preferred uneven distribution state described above. For this reason, when the surface of the preliminary-cured material is roughened, the surface roughness of the roughened surface of the roughened preliminary-cured material is further reduced. Furthermore, when the melting point or softening point of the epoxy resin is not less than the above lower limit and not more than the above upper limit, the adhesive strength between the cured product obtained by curing the roughened preliminary cured product and the metal layer is also increased.

  From the viewpoint of further reducing the surface roughness of the roughened surface of the roughened precured product and further increasing the adhesive strength between the cured product and the metal layer, the epoxy equivalent of the epoxy resin is preferably Is 90 or more, more preferably 100 or more, preferably 1000 or less, more preferably 800 or less.

  The epoxy resin preferably has a weight average molecular weight of 1000 or less. In this case, the content of silica in the epoxy resin material can be increased. Furthermore, even if there is much content of a silica, the resin composition which is an epoxy resin material with high fluidity | liquidity can be obtained. On the other hand, the combined use of an epoxy resin having a weight average molecular weight of 1000 or less and a phenoxy resin can suppress a decrease in melt viscosity of the B stage film that is an epoxy resin material. For this reason, when a B stage film is laminated on a board | substrate, the uneven distribution state of a silica can be made favorable.

[Curing agent]
The curing agent contained in the epoxy resin material is not particularly limited. A conventionally known curing agent can be used as the curing agent. As for a hardening | curing agent, only 1 type may be used and 2 or more types may be used together.

  Examples of the curing agent include cyanate ester resin (cyanate ester curing agent), phenol compound (phenol curing agent), amine compound (amine curing agent), thiol compound (thiol curing agent), imidazole compound, phosphine compound, acid anhydride, Examples include active ester compounds and dicyandiamide. Especially, from a viewpoint of obtaining the hardened | cured material in which the dimensional change by a heat | fever is still smaller, it is preferable that the said hardening | curing agent is cyanate ester resin or a phenol compound. The curing agent is preferably a cyanate ester resin, and is preferably a phenol compound. The curing agent preferably has a functional group capable of reacting with the epoxy group of the epoxy resin.

  From the viewpoint of further reducing the surface roughness of the roughened surface of the roughened precured product and further increasing the adhesive strength between the cured product and the metal layer, the curing agent is a cyanate ester resin, A phenol compound or an active ester compound is preferred. Furthermore, from the viewpoint of imparting good insulation reliability with a curing agent, the curing agent is more preferably a cyanate ester resin.

  By using the cyanate resin, the handling property of the B stage film having a high silica content can be improved, and the glass transition temperature of the cured product can be further increased. The cyanate ester resin is not particularly limited. A conventionally known cyanate ester resin can be used as the cyanate ester resin. As for the said cyanate ester resin, only 1 type may be used and 2 or more types may be used together.

  Examples of the cyanate ester resin include novolac type cyanate resin and bisphenol type cyanate resin. Examples of the bisphenol type cyanate resin include bisphenol A type cyanate resin, bisphenol E type cyanate resin, and tetramethylbisphenol F type cyanate resin.

  Commercially available products of the above-mentioned cyanate ester resins include phenol novolak cyanate resins (“PT-30” and “PT-60” manufactured by Lonza Japan), and prepolymers obtained by triazation of bisphenol A dicyanate into trimers. (Lonza Japan "BA230", "BA200" and "BA3000").

  By using the phenol compound, the adhesive strength between the cured product and the metal layer can be further increased. Moreover, by using the phenol compound, for example, the adhesion between the cured product and copper can be further enhanced by blackening or Cz treatment of the surface of copper provided on the surface of the cured product.

  The phenol compound is not particularly limited. A conventionally well-known phenol compound can be used as this phenol compound. As for the said phenol compound, only 1 type may be used and 2 or more types may be used together.

  Examples of the phenol compound include novolak type phenol, biphenol type phenol, naphthalene type phenol, dicyclopentadiene type phenol, aralkyl type phenol, dicyclopentadiene type phenol and the like.

  Commercially available products of the above-mentioned phenol compounds include novolak-type phenols (“TD-2091” manufactured by DIC), biphenyl novolac-type phenols (“MEH-7851” manufactured by Meiwa Kasei Co., Ltd.), and aralkyl-type phenol compounds (“MEH manufactured by Meiwa Kasei Co., Ltd.). -7800 ") and the like.

  From the viewpoint of further reducing the surface roughness of the roughened surface of the roughened preliminary-cured product and further increasing the adhesive strength between the cured product and the metal layer, the phenol compound is a biphenyl novolac type phenol. Or an aralkyl-type phenol compound.

  The active ester compound is not particularly limited. As a commercial item of the said active ester compound, "EXB-9460S-65T" by DIC, etc. are mentioned.

  The surface roughness of the roughened surface of the roughened preliminary-cured product is further reduced, the adhesive strength between the cured product and the metal layer is further increased, and good insulation reliability is imparted by the curing agent. From the viewpoint, the curing agent preferably includes a curing agent having an equivalent weight of 250 or less. For example, when the curing agent is a cyanate ester resin, the equivalent of the curing agent indicates a cyanate ester group equivalent, and when the curing agent is a phenol compound, it indicates a phenolic hydroxyl group equivalent, and the curing agent is an active ester compound. Is the active ester group equivalent.

  The weight average molecular weight of the curing agent is preferably 1000 or less. In this case, the content of silica in the epoxy resin material can be increased, and a resin composition that is an epoxy resin material having high fluidity can be obtained even if the content of silica is large. On the other hand, the combined use of a curing agent having a weight average molecular weight of 1000 or less and a phenoxy resin can suppress a decrease in melt viscosity of the B stage film that is an epoxy resin material. For this reason, when a B stage film is laminated on a board | substrate, the uneven distribution state of a silica can be made favorable.

  The total content of the epoxy resin and the curing agent in 100% by weight of the total solid content excluding the silica contained in the epoxy resin material (hereinafter sometimes abbreviated as total solid content B) is: Preferably it is 75 weight% or more, More preferably, it is 80 weight% or more, 100 weight% or less, Preferably it is 99 weight% or less, More preferably, it is 97 weight% or less.

  When the total content of the epoxy resin and the curing agent is not less than the above lower limit and not more than the above upper limit, a better cured product can be obtained and the melt viscosity can be adjusted, so that the presence state of silica is changed. The B stage film can be prevented from spreading in an unintended region during the curing process. Furthermore, the dimensional change due to heat of the cured product can be further suppressed. Further, if the total content of the epoxy resin and the curing agent is less than the lower limit, it becomes difficult to embed the resin composition or the B-stage film in the holes or irregularities of the circuit board, and the silica is unevenly distributed. Tend to get worse. When the total content of the epoxy resin and the curing agent exceeds the upper limit, the melt viscosity becomes too low and the B stage film tends to wet and spread in an unintended region during the curing process. “Total solid content B” refers to the total of the epoxy resin, the curing agent, and other solid content blended as necessary. The total solid content B does not contain silica. “Solid content” refers to a non-volatile component that does not volatilize during molding or heating.

  The compounding ratio of the epoxy resin and the curing agent is not particularly limited. The compounding ratio of the epoxy resin and the curing agent is appropriately determined depending on the kind of the epoxy resin and the curing agent.

[filler]
The epoxy resin material contains silica.

  The average particle diameter of all silica contained in the epoxy resin material is preferably 0.1 μm or more, and preferably 0.8 μm or less.

  As the average particle diameter of the silica, a median diameter (d50) value of 50% is adopted. The average particle size can be measured using a laser diffraction / scattering particle size distribution measuring apparatus.

  The silica contained in the epoxy resin material includes a first small particle size silica having a particle size of 0.01 μm or more and 0.5 μm or less, and a second particle size of 0.5 μm or more and 20 μm or less. Contains large particle size silica. Said 1st small particle size silica is a silica whose particle diameter is 0.01 micrometer or more and 0.5 micrometer or less among all the silica contained in the said epoxy resin material. Said 2nd large particle diameter silica is a silica whose particle diameter is 0.5 micrometer or more and 20 micrometers or less among all the silica contained in the said epoxy resin material.

  The particle diameter in the first small particle diameter silica and the second large particle diameter silica means a diameter when the silica is a true sphere, and means a maximum diameter when the silica is other than a true sphere. To do.

  By combining the specific first small particle size silica having a relatively small particle size and the specific second large particle size silica having a relatively large particle size, together with the epoxy resin and the curing agent, In the pre-cured product before the roughening treatment in which the epoxy resin material is pre-cured, silica is satisfactorily present. As a result, when the surface of the preliminary-cured product is roughened, the surface roughness of the roughened pre-cured product can be reduced, and the roughened preliminary-cured product is further cured. The adhesive strength between the object and the metal layer can be increased.

  More preferably, the silica is fused silica. By using fused silica, the surface roughness of the roughened surface of the roughened preliminary-cured product can be effectively reduced. The shape of silica is preferably substantially spherical.

  The silica contained in the epoxy resin material, the first small particle size silica, and the second large particle size silica are each preferably surface-treated, and surface-treated with a coupling agent. It is more preferable. As a result, the surface roughness of the roughened surface of the roughened precured material is further reduced, the adhesive strength between the hardened material and the metal layer is further increased, and the inter-wiring insulation reliability is further improved. And interlayer insulation reliability can be imparted.

  Examples of the coupling agent include silane coupling agents, titanate coupling agents, and aluminum coupling agents. The coupling agent used for the surface treatment may be epoxy silane, amino silane, vinyl silane, mercapto silane, sulfur silane, N-phenyl-3-aminopropyl silane, (meth) acrylic acid silane, isocyanate silane, ureido silane, or the like. preferable.

  The epoxy resin material preferably includes the first small particle size silica and the second large particle size silica in a weight ratio of 5:95 to 50:50, preferably 10:90 to 30:70. More preferably. When the epoxy resin material contains the first small particle size silica and the second large particle size silica in the weight ratio, the surface roughness of the roughened surface of the roughened preliminary-cured product is further increased. Further, the adhesive strength between the cured product and the metal layer is further increased.

  Content of all the said silica in 100 volume% of epoxy resin materials is 40 volume% or more. The content of all the silica in 100% by volume of the epoxy resin material is preferably 95% by volume or less, more preferably 90% by volume or less, and still more preferably 85% by volume or less. Further, in 100% by weight of the total solid content (hereinafter sometimes abbreviated as total solid content A) contained in the epoxy resin material, all of the silica (the first small particle size silica and the second large particle size). The particle size of silica is preferably 30% by weight or more, more preferably 40% by weight or more, still more preferably 50% by weight or more, preferably 85% by weight or less, more preferably 80% by weight or less. . When the content of the silica is not less than the above lower limit and not more than the above upper limit, the linear thermal expansion coefficient of the resin is suppressed, the difference in expansion coefficient from copper or silicon is alleviated, the thermal shock reliability is improved, and the warp suppressing effect is achieved. The processing accuracy is improved, and the silica is removed by the roughening treatment, and the formation of the roughened hole increases the adhesive strength between the cured product and the metal layer. “Total solid content A” refers to the sum of the epoxy resin, the curing agent, silica, and the solid content blended as necessary. “Solid content” refers to a non-volatile component that does not volatilize during molding or heating.

  The total content of the first small particle size silica and the second large particle size silica is preferably 60% by weight or more, more preferably 80% by weight, out of all the silica content of 100% by weight. More preferably, it is 90% by weight or more, particularly preferably 95% by weight or more. All the silicas may be the first small particle size silica and the second large particle size silica.

[Details of other components and resin composition and epoxy resin material]
The said epoxy resin material may contain the hardening accelerator as needed. By using a curing accelerator, the curing rate can be further increased. By rapidly curing the epoxy resin material, the crosslinked structure of the cured product can be made uniform, the number of unreacted functional groups can be reduced, and as a result, the crosslinking density can be increased. The curing accelerator is not particularly limited. As the curing accelerator, a conventionally known curing 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).

  From the viewpoint of increasing the insulation reliability of the cured product, the curing accelerator is particularly preferably an imidazole compound.

  The content of the curing accelerator is not particularly limited. From the viewpoint of efficiently curing the epoxy resin material, the content of the curing accelerator in the total solid content B of 100% by weight is preferably 0.01% by weight or more, and preferably 3% by weight or less. The total solid content B includes the curing accelerator.

  The epoxy resin material preferably contains a thermoplastic resin. By using the thermoplastic resin, the followability to the unevenness of the circuit of the epoxy resin material is increased, the surface roughness of the roughened surface of the roughened preliminary-cured material is further reduced, and further roughened. The surface roughness can be made even more uniform.

  Examples of the thermoplastic resin include phenoxy resin and polyvinyl acetal resin.

  The content of the thermoplastic resin is not particularly limited. The content of the thermoplastic resin in the total solid content B of 100% by weight is preferably 0.1% by weight or more, more preferably 0.5% by weight or more, still more preferably 1% by weight or more, preferably 40% by weight. Hereinafter, it is more preferably 30% by weight or less, further preferably 20% by weight or less, and particularly preferably 15% by weight or less. When the content of the thermoplastic resin is not less than the above lower limit and not more than the above upper limit, the dimensional change due to heat of the cured product is further reduced. Moreover, the embedding property with respect to the hole or unevenness | corrugation of the circuit board of an epoxy resin material becomes it favorable that content of the said thermoplastic resin is below the said upper limit. The total solid content B includes the thermoplastic resin.

  For the purpose of improving impact resistance, heat resistance, resin compatibility and workability, epoxy resin materials include coupling agents, colorants, antioxidants, UV degradation inhibitors, antifoaming agents, and thickeners. A thixotropic agent and other resins other than those mentioned above 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 amino silane, imidazole silane, vinyl silane, phenylamino silane, and epoxy silane.

  The content of the coupling agent is not particularly limited. In the total solid content B of 100% by weight, the content of the coupling agent is preferably 0.01% by weight or more and 5% by weight or less.

  Examples of the other resin include polyphenylene ether resin, divinyl benzyl ether resin, polyarylate resin, diallyl phthalate resin, polyimide resin, benzoxazine resin, benzoxazole resin, bismaleimide resin, and acrylate resin. The total solid content B includes the coupling agent.

  The epoxy resin material may contain a solvent. 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. As for the said solvent, only 1 type may be used and 2 or more types may be used together.

  The resin composition containing a solvent can be used as a varnish. The viscosity of the varnish can be adjusted by adjusting the solvent content according to the application. In the epoxy resin material, the content of the solvent is preferably 10 parts by weight or more and preferably 1000 parts by weight or less with respect to 100 parts by weight of the total solid content A.

(Details of B-stage film, laminated film, pre-cured product, roughened pre-cured product and laminate)
The epoxy resin material may be a resin composition or a B-stage film in which the resin composition is formed into a film. A B-stage film can be obtained by forming the resin composition into a film.

  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. Examples thereof include a casting molding method in which the resin composition is dissolved or dispersed in a solvent such as an organic solvent and then cast into a film, and other conventionally known film molding methods. Of these, the extrusion molding method or the casting molding method is preferable because the thickness can be reduced. The film includes a sheet.

  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 10 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 said resin composition is used suitably in order to form a laminated film provided with a base material and the B stage film laminated | stacked on one surface of this base material. A B-stage film of a laminated film is formed from the resin composition.

  Examples of the base material 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, polyimide resin film, metal foil such as copper foil and aluminum foil, and the like. Can be mentioned. The surface of the base material may be subjected to a release treatment as necessary.

  When the epoxy resin material is used as an insulating layer of a circuit, the thickness of the layer formed of the epoxy resin material is preferably equal to or greater than the thickness of the conductor layer that forms the circuit. The thickness of the layer formed of the epoxy resin material is preferably 5 μm or more, and preferably 200 μm or less.

  The epoxy resin material is a B-stage film, and it is preferable that the B-stage film is laminated on the lamination target member and then the B-stage film is cured to obtain a precured product. The laminating temperature is preferably 55 ° C. or higher, more preferably 65 ° C. or higher, preferably 130 ° C. or lower, more preferably 120 ° C. or lower. The laminating pressure is preferably 0.5 MPa or more, more preferably 0.8 MPa or more, preferably 1.5 MPa or less, more preferably 1.2 MPa or less. By laminating the B stage film, which is an epoxy resin material, under such optimized conditions, the pre-cured product has a better distribution of the first small particle size silica and the second large particle size silica. become. In the B stage film composed of the epoxy resin material as described above, the melt viscosity near the lamination temperature is low. In particular, the melt viscosity of the B stage film composed mainly of a liquid epoxy resin and a cyanate ester curing agent is 50 Pa · s or less, and the fluidity of the resin component is increased. By laminating in this state, the first small particle size silica can be selectively moved when the resin melts, and the first surface together with the resin on the outermost surface of the B-stage film so that it becomes flat during lamination. Of small particle size silica moves. By this movement, a large amount of the first small particle size silica is unevenly distributed on the first surface side to be roughened. Moreover, when many resin with low melt viscosity is contained, the amount of movement of resin increases at the time of lamination, and a layer with little silica content is formed. A large amount of the first small particle size silica having a relatively small particle size is present in the upper layer portion of the precured product, and a large amount of the second large particle size silica having a relatively large particle size is present in the lower layer portion. As a result, when the surface of the precured product is roughened, the surface roughness of the roughened surface of the roughened precured product is reduced. Furthermore, the adhesive strength between the cured product and the metal layer is also increased. Moreover, by lowering the melt viscosity of the resin, a resin layer having a clearly low silica content can be formed between the upper layer and the lower layer, and the insulating properties of the upper layer and the lower layer of the roughened precured product can be increased. Further, the amount of silica in the third region is relatively increased, the linear thermal expansion coefficient (CTE) in the direction parallel to the layer is kept low, and curing that reduces the warpage of the insulating substrate using this roughened precured product can also be obtained. .

  The method for laminating by laminating the B-stage film can be a known method, and is not particularly limited. For example, the B-stage film is laminated on a circuit board, preferably the laminated film is laminated from the B-stage film side, and pressurized using a pressure laminator. At this time, it may be heated or not heated. Next, using a parallel plate press type heat press, the lamination target member and the B stage film or laminated film are heated and pressurized. The pre-cured product may be formed by pre-curing the B-stage film by heating and pressing. The heating temperature and the pressurizing pressure can be appropriately changed and are not particularly limited.

  As a more specific lamination method, for example, using a roll laminator, the roll temperature is set to 20 to 120 ° C. under the conditions of a roll diameter of 60 mm and a roll peripheral speed of 0.1 to 10 m / min, and 1 to 6 MPa. While pressing with pressure, the B-stage film is laminated on the circuit board, or the laminated film is laminated on the lamination target member from the B-stage film side.

  After laminating the B-stage film or the laminated film on the lamination target member, it is preferable to perform a heat treatment at 160 to 200 ° C. for 20 to 180 minutes. The B stage film can be precured by heat treatment to obtain a precured product. The base material of the laminated film may be removed before forming the precured product, or may be removed after forming the precured product. After laminating under such conditions, by performing a roughening treatment, fine irregularities can be formed on the surface of the roughened preliminary-cured product. The precured product is preferably cured at a temperature lower by 10 to 60 ° C. than the glass transition temperature of the final cured product.

  If necessary, a parallel plate heating press machine may be used after roll lamination to improve the smoothness of the surface of the precured product. For example, a laminate of a circuit board and a B stage film or a laminated film may be heated and pressurized with a stainless steel plate having a thickness of 1 mm using a parallel plate heating press.

  In addition, a commercially available apparatus can be used as a press machine such as a pressurizing laminator such as a hot pressurizing roll laminator and a parallel plate heating press machine. Lamination with a roll laminator is preferably performed in a vacuum state. The material of the roll of the roll laminator can be appropriately selected from a rubber roll having a soft surface and a metal roll having a hard surface. The material of the flat plate of the parallel plate heating press is a hard metal.

  A release function is provided between a roll laminator roll and the above-described lamination target member, B-stage film or laminated film, or between a flat plate of a parallel plate heating press and the above-mentioned lamination target member, B-stage film or laminated film. For example, an aluminum foil, a copper foil, a polyester resin film, a fluororesin film, or the like may be used.

  For the purpose of improving the adhesion between the circuit board and the B stage film or the laminated film, a flexible material such as a rubber sheet may be used.

  The pre-cured product is formed by laminating the laminated film on the circuit board from the B-stage film side, pressurizing it using a roll laminator, and then heating and heating using a parallel plate press type hot press machine. It is preferable to be a step of forming a precured product by pressing. In addition, the step of forming the precured product is performed by laminating the laminated film on the lamination target member from the B stage film side, pressurizing it using a roll laminator, and then using a parallel plate press type hot press machine. This is a process of heating and pressurizing to form a pre-cured product. After pressurizing using a roll laminator and before heating and pressurizing using a parallel plate press type hot press machine, or using a roll laminator It is preferable to remove the base material after pressing and heating and pressurizing using a parallel plate press type hot press.

  The roughened preliminary-cured product according to the present invention is obtained by subjecting the first main surface of the preliminary-cured product to a roughening treatment. In order to form fine irregularities on the surface of the preliminary-cured product, it is preferable that the rough-cured preliminary-cured product is subjected to a swelling treatment before the roughening treatment. The roughened precured product is preferably subjected to a swelling treatment after the precuring and before the roughening treatment. However, the pre-cured product may not necessarily be subjected to the swelling treatment.

  The laminate according to the present invention includes a cured product obtained by curing a roughened preliminary cured product obtained by roughening the first main surface of the preliminary cured product, and a roughened treatment of the cured product. And a metal layer laminated on the surface. The adhesive strength between the cured product and the metal layer is preferably 0.39 N / mm or more. The metal layer is preferably a copper layer, and more preferably a copper plating layer.

(Printed wiring board)
The said epoxy resin material is used suitably in order to form an insulating layer in a printed wiring board.

  The printed wiring board can be obtained, for example, by heat-pressing the B stage film using a B stage film formed of the resin composition.

  A metal foil can be laminated on one side or both sides of the B-stage film. The method for laminating the B-stage film and the metal foil is not particularly limited, and a known method can be used. For example, the B-stage 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 said epoxy resin material is used suitably in order to obtain a copper clad laminated board. An example of the copper-clad laminate is a copper-clad laminate comprising a copper foil and a B stage film laminated on one surface of the copper foil. The B-stage film of this copper-clad laminate is formed from the above epoxy resin material. By pre-curing the B-stage film, a copper-clad laminate having a pre-cured product can be obtained.

  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 hardened | cured material which hardened | cured epoxy resin material, 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.

  Moreover, the said precured material is used suitably in order to obtain a multilayer substrate. As an example of the multilayer substrate, there is a circuit substrate including a circuit substrate and a cured product layer laminated on the surface of the circuit substrate. The cured product layer of the multilayer substrate is formed by roughening the precured product and then curing the roughened precured product. It is preferable that the said hardened | cured material layer is laminated | stacked on the surface in which the circuit of the circuit board was provided. Part of the cured product layer is preferably embedded between the circuits.

  In the multilayer substrate, it is more preferable that the surface of the cured product 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 cured product layer may be swelled 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 hardened | cured material layer was carried out.

  Further, as another example of the multilayer board, a circuit board, a cured product layer laminated on the surface of the circuit board, and a surface of the cured product layer opposite to the surface on which the circuit board is laminated are provided. A circuit board provided with the laminated copper foil is mentioned. Using the copper-clad laminate provided with the cured product layer and the copper foil, the copper stage and a B stage film laminated on one surface of the copper foil, the B stage film is precured, roughened, and It is preferably formed by a curing treatment. Furthermore, it is preferable that the copper foil is etched and is a copper circuit.

  Another example of the multilayer board is a circuit board including a circuit board and a plurality of cured product layers stacked on the surface of the circuit board. At least one of the plurality of cured product layers is formed of the preliminary-cured product. It is preferable that the multilayer substrate further includes a circuit laminated on at least one surface of the cured product layer formed by curing the epoxy resin material.

  In FIG. 2, the laminated body using the precured material which concerns on one Embodiment of this invention is typically shown with a partial notch front sectional drawing.

  In the laminate 11 shown in FIG. 2, a plurality of cured product layers 13 to 16 are laminated on the upper surface 12 a of the circuit board 12. The cured product layers 13 to 16 are insulating 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 cured product layers 13 to 16, the cured product layers 13 to 15 other than the cured product layer 16 located on the outer surface opposite to the circuit board 12 side include a metal layer in a partial region of the upper surface. 17 is formed. The metal layer 17 is a circuit. Metal layers 17 are respectively arranged between the circuit board 12 and the cured product layer 13 and between the laminated cured product 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 laminate 11, the cured product layers 13 to 16 are formed by curing the epoxy resin material according to the present invention. In FIG. 2, for convenience of illustration, silica and holes from which silica has been removed in the cured product layers 13 to 16 are not shown. In the present embodiment, since the surfaces of the cured product layers 13 to 16 are roughened, fine holes (not shown) are formed on the surfaces of the cured product layers 13 to 16. Further, the metal layer 17 reaches the inside of the fine hole. Moreover, in the laminated body 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. Moreover, in the laminated body 11, favorable insulation reliability is provided between the upper metal layer and lower metal layer which are not connected by the via-hole connection and through-hole connection which are not shown in figure.

(Swelling treatment and roughening treatment)
As a method for the swelling treatment, for example, a method of treating a precured product with an aqueous solution or an organic solvent dispersion solution 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 a precured 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 roughened 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 precured product once or twice under conditions is preferable. It is preferable that the temperature of the said roughening process exists in the range of 50-85 degreeC.

  The arithmetic average roughness Ra of the roughened surface of the roughened preliminary-cured product is preferably 50 nm or more, more preferably 350 nm or less, and still more preferably 300 nm or less. In this case, the adhesive strength between the cured product and the metal layer can be further increased, and further finer wiring can be formed on the surface of the cured product layer.

(Desmear treatment)
Moreover, a through-hole may be formed in the said precured material or the said hardened | cured material. 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 layer is often formed at the bottom of the via.

  In order to remove the smear, the surface of the preliminary-cured product is preferably desmeared. The desmear process may also serve as a roughening process. The desmear process is sometimes called 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 A method of treating a precured product or a cured product once or twice is preferable. It is preferable that the temperature of the said desmear process exists in the range of 50-85 degreeC.

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

  In the examples and comparative examples, the following materials were used.

(Epoxy resin)
Epoxy resin 1 (bisphenol F type epoxy resin, “828US” manufactured by Mitsubishi Chemical)
Epoxy resin 2 (biphenyl novolac type epoxy resin, Nippon Kayaku Co., Ltd. “NC3000H”, softening point 70 ° C.)
Epoxy resin 3 (dicyclopentadiene type epoxy resin, DIC "HP-7200", softening point 61 ° C)

(Curing agent)
Active ester compound solution (includes "EXB-9460S-65T" manufactured by DIC, active ester equivalent 223, active ester compound (solid content) 65 wt% and toluene 35 wt%)
Cyanate ester resin solution (cyanate ester curing agent, bisphenol A dicyanate triazine-modified prepolymer, Lonza Japan "BA230S-75", cyanate equivalent 230, cyanate ester resin (solid content) 75 weight And 25% by weight of methyl ethyl ketone)
Phenol compound (phenol curing agent, “MEH7851-4H” manufactured by Meiwa Kasei Co., Ltd., phenolic hydroxyl group equivalent 242)
Phenol compound solution (phenol curing agent having aminotriazine skeleton, “LA3018-50P” manufactured by DIC, phenolic hydroxyl group equivalent 151, phenol compound (solid content) 50 wt% and propylene glycol monomethyl ether 50 wt%)

(Curing accelerator)
Imidazole compound 1 (2-ethyl-4-methylimidazole, “2E4MZ” manufactured by Shikoku Kasei Co., Ltd.)
Imidazole Compound 2 (2-Phenyl-4-methyl-5-hydroxymethylimidazole, “2P4MHZ-PW” manufactured by Shikoku Kasei Co., Ltd.)

(Silica component)
First small particle size silica-containing slurry A:
The first small particle size silica a (silica (Admatex “YA050C-MMK”, average particle size 0.05 μm) is phenylsilane (phenyltrimethoxysilane, Shin-Etsu Chemical Co., Ltd. “KBM-103”)) 1st small particle size silica-containing slurry containing 65% by weight and 35% by weight of methyl ethyl ketone. First small particle size silica-containing slurry B:
The first small particle size silica b (silica (“UFP-30” manufactured by Denki Kagaku Kogyo Co., Ltd., average particle size 0.1 μm) was surface-treated with imidazole silane (“IM-1000” manufactured by Nikko Metal Co., Ltd.)) 1) small-sized silica-containing slurry containing 30% by weight of N) and 70% by weight of N, N-dimethylformamide containing both the first small-sized silica and the second large-sized silica. Slurry X:
The first small particle size silica and the second large particle size silica x (silica (“SO-C2” manufactured by Admatechs Co., Ltd., average particle size: 0.5 μm) are combined with epoxysilane (3-glycidoxypropyltrimethoxy). Silane, surface treated with “KBM-403” manufactured by Shin-Etsu Chemical Co., Ltd.)) both first small particle size silica and second large particle size silica containing 70% by weight and 30% by weight methyl ethyl ketone Slurry containing

  Slurry X has a wide particle size distribution and contains silica having a particle size of 0.01 μm to 20 μm. In the slurry X, the content of the first small particle size silica is 50% by volume in the total of 100% by volume of the first small particle size silica and the second large particle size silica, and the second large particle size silica x The content of is 50% by volume.

Second large particle size silica-containing slurry Y:
The second large particle size silica y (Silica (“UF-320” manufactured by Tokuyama, average particle size 3.5 μm, coarse cut point 20 μm) is surface-treated with imidazole silane (“IM-1000” manufactured by Nikko Metal Co., Ltd.)). And a second large particle size silica-containing slurry containing 50% by weight and 50% by weight of N, N-dimethylformamide.

(Thermoplastic resin)
Butyral resin ("KS-1" manufactured by Sekisui Chemical Co., Ltd.)

Example 1
(1) Production of Resin Composition and Laminate Film First small particle size silica-containing slurry A is 5 parts by weight in solid content, second large particle size silica-containing slurry Y is 55 parts by weight in solid content, epoxy 10 parts by weight of resin 1 (bisphenol A type epoxy resin, “828 US” manufactured by Mitsubishi Chemical), 20 parts by weight of epoxy resin 2 (biphenyl novolac type epoxy resin, “NC3000H” manufactured by Nippon Kayaku Co., Ltd.), and cyanate ester resin solution ( Cyanate ester curing agent, “BA230S-75” manufactured by Lonza Japan Co., Ltd., 10 parts by weight, 0.5 part by weight of imidazole compound 1 (“2E4MZ” manufactured by Shikoku Kasei Co., Ltd.), butyral resin "KS-1") 0.3 part by weight was blended and stirred for 1 hour at 1200 rpm using a stirrer to obtain a resin composition.

  A release-treated transparent polyethylene terephthalate (PET) film (“PET5011 550” manufactured by Lintec Corporation, thickness 50 μm) was prepared. The obtained resin composition was applied on the release-treated surface of this PET film using an applicator so that the thickness after drying was 50 μm. Next, it was dried in a gear oven at 100 ° C. for 2 minutes to prepare a laminated film of an uncured resin sheet (B stage film) having a length of 200 mm × width of 200 mm × thickness of 50 μm and a polyethylene terephthalate film. Next, the polyethylene terephthalate film was peeled from the laminated film, and the uncured product of the resin sheet was heated in a gear oven at 180 ° C. for 80 minutes to prepare a precured product of the resin sheet.

(2) Production of Laminate Having Precured Product Set the obtained laminated film so that the B stage film is on the glass epoxy substrate (FR-4, product number “CS-3665”, manufactured by Risho Kogyo Co., Ltd.). did. The laminated film and the glass epoxy substrate were heated under pressure at 0.5 MPa for 60 minutes under a reduced pressure using a parallel plate press heated to 100 ° C. to obtain a laminated body containing a precured resin sheet. Thereafter, the polyethylene terephthalate film was peeled off to obtain a laminate A of a glass epoxy substrate and a precured product. The obtained preliminary-cured product has a second main surface on the glass epoxy substrate side and a first main surface which is a surface to be roughened on the side opposite to the glass epoxy substrate.

(Examples 2-8 and Comparative Examples 1-2)
Resin composition, laminated film of PET film and B stage film, and glass epoxy substrate and spare, in the same manner as in Example 1 except that the type and amount of materials used were changed as shown in Table 1 below. A laminate with a cured product was obtained.

(Evaluation)
(1) Minimum melt viscosity of epoxy resin material Uncured resin sheet obtained using a Rheometer device ("AR-2000" manufactured by TA Instruments) under the conditions of strain of 21.6% and frequency of 1 Hz. The viscosity of the (B stage film) in the temperature range of 50 to 150 ° C. was measured, and the value at which the viscosity was the lowest was taken as the minimum melt viscosity.

(2) Silica presence state 1
The cross-section observation of the precured material in the laminated body A obtained by the Example and the comparative example was performed. The presence state 1 of silica in the precured body was determined according to the following criteria.

[Criteria for existence state 1 of silica]
○: The content of the second large particle size silica in the 100% by volume of all silica contained in the first region having a thickness of 0.3 μm in the surface portion on the first main surface side in the precured body is In the second region having a thickness of 5% by volume or less and continuous with the first region and having a thickness of 1 μm, the content of all silica in 100% by volume of the second region is 20% by volume or less. The content of the second large particle size silica is 5% by volume out of 100% by volume of all silica contained in the first region having a thickness of 0.3 μm in the surface portion on the first main surface side in the cured body. Or in the second region having a thickness of 1 μm connected to the first region, the content of all silica exceeds 20% by volume in 100% by volume of the second region. XX: Precured body Among all the silica contained in the first region having a thickness of 0.3 μm on the surface portion on the first main surface side In 00 volume%, the content of the second large particle size silica exceeds 5 volume%, and in the second area having a thickness of 1 μm connected to the first area, 100 volume% of the second area. Medium, the content of all silica exceeds 20% by volume

(3) Silica presence state 2
When the determination result of the presence state 1 of the silica is “◯”, the surface portion of the first main surface side, which is a surface to be roughened, has a thickness of 0.3 μm from the surface. The content ratio (volume%) of the second large particle size silica out of 100% by weight of all silica contained was evaluated.

(4) Adhesive strength (peel strength) and arithmetic average roughness Ra
[Preparation of cured product B]
The pre-cured product in the laminate A was subjected to the following (a) swelling treatment, then the following (b) permanganate treatment, that is, roughening treatment, and further the following (c) copper plating treatment.

(A) Swelling treatment:
The laminate A was placed in a 60 ° C. swelling liquid (Swelling Dip Securigant P, manufactured by Atotech Japan Co., Ltd.) and rocked for 20 minutes. Thereafter, it was washed with pure water.

(B) Permanganate treatment:
Roughening preliminary hardening which put the above-mentioned layered product into a roughening aqueous solution of potassium permanganate (Concentrate Compact CP, manufactured by Atotech Japan Co.) at 75 ° C. and shaken for 20 minutes and roughened it on a glass epoxy substrate. I got a thing. The obtained roughened preliminary-cured product was washed with a cleaning solution at 23 ° C. (Reduction Securigant P, manufactured by Atotech Japan) for 2 minutes, and further washed with pure water.

  After drying in a gear oven at 120 ° C. for 2 hours and cooling, the arithmetic average roughness Ra of the roughened surface of the roughened preliminary-cured product was measured according to JIS B0601-1994.

(C) Copper plating treatment:
Next, electroless copper plating and electrolytic copper plating treatment were performed on the roughened preliminary-cured material subjected to the roughening treatment on the glass epoxy substrate by the following procedure.

  The surface of the roughened preliminary-cured product was treated with an alkaline cleaner (cleaner securigant 902) at 55 ° C. for 5 minutes and degreased and washed. After washing, the roughened precured product was treated with a 23 ° C. pre-dip solution (Pre-dip Neogant B) for 2 minutes. Thereafter, the roughened preliminary-cured product was treated with an activator solution (activator Neogant 834) at 40 ° C. for 5 minutes to attach a palladium catalyst. Next, the roughened preliminary-cured material was treated for 5 minutes with a reducing solution (reducer Neogant WA) at 30 ° C.

  Next, the above roughened preliminary cured product is put in a chemical copper solution (basic print Gantt MSK-DK, copper print Gantt MSK, stabilizer print Gantt MSK), and electroless plating is performed until the plating thickness becomes about 0.5 μm. did. After the electroless plating, annealing was performed at a temperature of 120 ° C. for 30 minutes in order to remove the remaining hydrogen gas. All the processes up to the electroless plating process were performed with a treatment liquid of 1 L on a beaker scale and while the cured product was rocked.

  Next, electrolytic plating was performed on the roughened preliminary-cured material that had been subjected to electroless plating until the plating thickness reached 25 μm. Using copper sulfate (reducer Cu) as the electrolytic copper plating, a current of 0.6 A / cm 2 was passed. After the copper plating treatment, the roughened preliminary-cured product was heated at 190 ° C. for 1 hour to be cured to obtain a cured product B on which a copper plating layer was formed. At this time, when swelling occurred between the substrate and the plating layer, it was evaluated as “plating swelling”.

[Measurement method of adhesive strength]
A cutout having a width of 10 mm was made on the surface of the copper plating layer of the cured product B on which the copper plating layer was formed. Thereafter, using a tensile tester (trade name “Autograph”, manufactured by Shimadzu Corporation), the adhesive strength (peel strength) between the copper plating layer and the cured product was measured under the condition of a crosshead speed of 5 mm / min.

[Insulation test method]
Aside from the adhesive strength test, after the electroless plating process is completed, DFR sub-hr is attached, exposure, DFR peeling, and copper etching process are performed, this is electroplated, an electrode pattern is formed, and an interlayer insulation test substrate is formed. Obtained. This interlayer insulation test substrate was evaluated by measuring the leakage current after 100 hours using an unsaturated insulation test apparatus of 130 ° C., 85%, 5V.

  The results are shown in Table 1 below. The average particle diameter of all silica contained in the resin composition that is an epoxy resin material is shown in Table 1 below. In Table 1 below, “total solid content A” indicates the total solid content contained in the epoxy resin material, and “−” indicates that no evaluation is made.

DESCRIPTION OF SYMBOLS 1 ... Precured material 1a ... 1st main surface 1b ... 2nd main surface 2 ... Silica 2A ... 1st small particle size silica 2B ... 2nd large particle size silica 6 ... Laminating object member 6a ... Upper surface 11 ... Laminated body 12 ... Circuit board 12a ... Upper surface 13-16 ... Hardened material layer 17 ... Metal layer R1 ... 1st area | region R2 ... 2nd area | region R3 ... 3rd area | region

Claims (7)

A pre-cured product obtained by proceeding with the curing of the epoxy resin material,
A first main surface and a second main surface, wherein the first main surface is a surface to be roughened;
The epoxy resin material includes an epoxy resin, a curing agent, and silica,
The content of all the silica in 100% by volume of the epoxy resin material is 40% by volume or more,
The silica contains a first small particle size silica having a particle size of 0.01 μm or more and less than 0.5 μm, and a second large particle size silica having a particle size of 0.5 μm or more and 20 μm or less. ,
In the precured product, the first small particle size silica and the second large particle size silica are unevenly distributed,
Inclusion of the second large particle size silica out of 100% by volume of all silica contained in the first region having a thickness of 0.3 μm of the surface portion on the first main surface side which is a surface to be roughened. The amount is 5% by volume or less,
In a second region having a thickness of 1 μm that is continuous with the first region, a pre-cured product in which the content of all the silica is 20% by volume or less in 100% by volume of the second region.   The precured product according to claim 1, wherein the minimum melt viscosity of the epoxy resin material before precuring in the temperature range of 60 to 120 ° C is 50 Pa · s or less.   The precured material according to claim 1 or 2, wherein the epoxy resin material includes a cyanate ester resin as the curing agent.   The roughening preliminary-cured material obtained by carrying out the roughening process of the said 1st main surface of the preliminary-curing material of any one of Claims 1-3.   The roughened preliminary-cured product according to claim 4, wherein the preliminary-cured product is subjected to a swelling treatment before the roughening treatment.   The hardened | cured material which hardened the roughened preliminary-cured material obtained by roughening the said 1st main surface of the preliminary-cured material of any one of Claims 1-3, A laminate having a metal layer laminated on a roughened surface.   The laminated body of Claim 6 whose adhesive strength of the said hardened | cured material and the said metal layer is 0.39 N / mm or more.

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