TW201413746A - Insulating resin film, pre-cured product, laminate, and multi-layer substrate - Google Patents

Abstract

Provided is an insulating resin film wherein it is possible to prevent changes in dimension caused by the heat of a cured product and to increase the adhesive strength between the cured product and a metal layer. This insulating resin film (1) is used after undergoing a roughening treatment. This insulating resin film (1) has a first main surface (1a) and a second main surface (1b). The first main surface (1a) undergoes the roughening treatment. This insulating resin film (1) contains an epoxy resin, a curing agent, and silica (2). Silica (2) is unevenly distributed such that the content of silica (2) within 100 weight% of a first region (R1), which contains the surface section on the side of the first main surface (1a) that underwent roughening treatment up to a thickness of 0.3 μm, is less than the content of silica (2) within 100 weight% of a second region (R2) which excludes the first region (R1). The content of silica (2) within 100 weight% of the second region (R2) is greater than 30 weight%.

Description

Insulating resin film, pre-cured material, laminated body and multilayer substrate

The present invention relates to an insulating resin film which can be preferably used, for example, for forming an insulating layer on a multilayer substrate. Moreover, the present invention relates to a pre-cured material, a laminate, and a multilayer substrate using the above-mentioned insulating resin film.

Conventionally, various resin compositions have been used in order 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 the inner layers or to form an insulating layer located in the surface layer portion. A wiring as a metal layer is generally laminated on the surface of the insulating layer.

Further, in the above resin composition, in order to reduce the linear expansion ratio and the like, the inorganic filler is often formulated. In recent years, with the miniaturization and high performance of electronic devices, the electronic components are required to have a finer wiring and a further reduction in the linear expansion ratio of the insulating layer. Further, in the insulating layer of the multilayer printed wiring board, it is strongly required that peeling is less likely to occur with other insulating layers or circuits laminated on the insulating layer. Therefore, it is preferable that the insulating layer does not largely change in size due to heat. In order to cope with such a demand, there is a case where a large amount of inorganic filler is formulated in the above resin composition for forming an insulating layer.

Moreover, as an example of the above-mentioned resin composition, the following Patent Document 1 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. 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 a multilayer film having a two-layered laminated structure is formed using the above two different resin compositions. Further, it is described that the multilayer film is favorably embedded in a gap or the like provided on the substrate.

Patent Document 2 listed below discloses an insulating resin material containing a curable resin, an inorganic filler, and a curing accelerator. The inorganic filler contains at least two fillers having different volume average particle diameters. The particle diameter (b1) having a small particle diameter is 0.01 to 1.0 μm, and the particle diameter of the second small particle (b2) is 0.30 to 10 μm. The ratio of the volume average particle diameter of the particles (b1) to the particles (b2) is 1/2 to 1/100, and the ratio of the weight content is 90/10 to 10/90. At least one of the particles (b1) and the particles (b2) is surface-treated by a decane coupling agent.

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2008-302677

Patent Document 2: Japanese Patent Laid-Open Publication No. 2004-277735

In Patent Document 1, since two types of resin compositions are prepared to produce a multilayer film, there is a problem in that the production of the multilayer film is troublesome and the cost is high. Further, there is also a problem that peeling easily occurs between the layers of the multilayer film. Further, when two types of resin layers are bonded by lamination or the like, since the physical properties of the two kinds of resin layers are different, there is a problem that stress is increased and warpage occurs.

In addition, in the multilayer resin film described in Patent Document 1 and the insulating resin material described in Patent Document 2, the surface roughness of the surface of the cured product cannot be sufficiently reduced. Further, when a metal layer is formed on the surface of the cured product by a plating treatment or the like, it is difficult to sufficiently increase the bonding strength between the cured product and the metal layer.

Further, in the case where a large amount of the inorganic filler is blended in the prior resin composition for forming the insulating layer in order to lower the coefficient of linear expansion, the resin combination is applied by plating treatment or the like. When the metal layer is formed on the surface of the cured product, there is also a problem that the strength of the cured product and the metal layer tends to be low.

Further, in the multilayer film described in Patent Document 1 and the insulating resin material described in Patent Document 2, it is not possible to sufficiently reduce the dimensional change caused by heat of the cured product, and the linear expansion ratio of the above insulating layer Relatively high.

An object of the present invention is to provide an insulating resin film, a pre-cured material, a laminate, and a multilayer substrate using the insulating resin film, wherein the insulating resin film can reduce dimensional change caused by heat of the cured product, and further harden When the surface of the object forms a metal layer, the adhesion strength between the cured product and the metal layer can be improved.

An object of the present invention is to provide an insulating resin film, a pre-cured material, a laminate, and a multilayer substrate using the insulating resin film, which can reduce the surface roughness of the surface of the cured product after the roughening treatment .

According to a broad aspect of the present invention, there is provided an insulating resin film which is subjected to a roughening treatment and which has a first main surface and a second main surface, wherein the first main surface is a roughened surface And containing the epoxy resin, the hardener, and the cerium oxide, the surface of the roughened surface, that is, the content of the above-mentioned cerium oxide in the first region 100% by weight of the surface portion of the first main surface side having a thickness of 0.3 μm a state in which the content of the cerium oxide in the second region other than the first region is less than 100% by weight, and the cerium oxide is distributed in a distributed manner, and the content of the cerium oxide in the second region is 100% by weight. More than 30% by weight.

In a specific aspect of the insulating resin film of the present invention, the content of the above-mentioned ceria in 100% by weight of the second region is more than 60% by weight.

In a specific aspect of the insulating resin film of the present invention, the content of the cerium oxide in 100% by weight of the first region is less than 10% by weight of the cerium oxide in 100% by weight of the second region. %the above.

In a specific aspect of the insulating resin film of the present invention, the above epoxy resin package Two or more kinds of first epoxy resins, and two or more of the first epoxy resins have the same structural unit, and the number of repetitions of the structural units of the two or more kinds of the first epoxy resins is different or the ring The oxyresin includes a second epoxy resin having a carbon-carbon unsaturated bond and a third epoxy resin having no carbon-carbon unsaturated bond.

In a specific aspect of the insulating resin film of the present invention, the content of the cerium oxide is 30% by weight or more and 85% by weight or less based on 100% by weight of the entire insulating resin film.

In a specific aspect of the insulating resin film of the present invention, the content of the cerium oxide is 60% by weight or more and 85% by weight or less based on 100% by weight of the entire insulating resin film.

In a specific aspect of the insulating resin film of the present invention, the first main surface is subjected to a swelling treatment and is subjected to a roughening treatment after the swelling treatment.

According to a broad aspect of the present invention, a pre-cured material which can be obtained by subjecting the first main surface of the insulating resin film to a roughening treatment can be provided.

According to a broad aspect of the present invention, there is provided a laminate comprising: a cured product obtained by using a pre-cured product obtained by roughening the first main surface of the insulating resin film, The pre-cured material is obtained by hardening the pre-cured material; and the metal layer is laminated on the roughened surface of the hardened material.

According to a broad aspect of the present invention, a multilayer substrate including a circuit board and an insulating layer disposed on the circuit board, wherein the insulating layer is roughened and hardened by the insulating resin film And formed.

The insulating resin film of the present invention contains the epoxy resin, the curing agent, and the cerium oxide, and the surface of the roughened surface, that is, the surface of the first main surface side has a thickness of 0.3 μm in the first region of 100% by weight. The content of the cerium oxide is less than the content of the cerium oxide in 100% by weight of the second region other than the first region, and the cerium oxide is biased In the cloth, and the content of the above-mentioned ceria in 100% by weight of the second region is more than 30% by weight, the dimensional change due to heat of the cured product of the insulating resin film can be reduced. Further, in the case where a metal layer is formed on the surface of the cured body on which the first main surface is roughened, the adhesion strength between the cured product and the metal layer can be improved.

1‧‧‧Insulating resin film

1a‧‧‧1st main face

1b‧‧‧2nd main face

2‧‧‧2 cerium oxide

6‧‧‧Multilayer object components

6a‧‧‧ surface

11‧‧‧Multilayer substrate

12‧‧‧ circuit board

12a‧‧‧Upper surface

13~16‧‧‧Insulation

17‧‧‧metal layer (wiring)

R1‧‧‧1st area

R2‧‧‧2nd area

Fig. 1 is a cross-sectional view schematically showing an insulating resin film according to an embodiment of the present invention.

Fig. 2 is a cross-sectional view schematically showing a multilayer substrate using an insulating resin film according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail.

(insulating resin film)

The insulating resin film of the present invention is used for roughening treatment. The insulating resin film of the present invention has a first main surface and a second main surface. The first main surface is a roughened surface. The insulating resin film of the present invention contains an epoxy resin, a hardener, and cerium oxide. In the insulating resin film of the present invention, the content of the cerium oxide in the first region 100% by weight of the surface portion of the surface of the first main surface side which is the roughened surface is 0.3 μm less than the above-mentioned The state of the content of the above-mentioned cerium oxide in 100% by weight of the second region other than the region 1 causes the cerium oxide to be distributed in a biased manner. Further, in the insulating resin film of the present invention, the content of the cerium oxide in 100% by weight of the second region is more than 30% by weight.

The insulating resin film of the present invention is a single layer film and is not a multilayer film. Therefore, it does not occur in the case of the use of a multilayer film, which is a problem of interlayer peeling.

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

The insulating resin film 1 shown in Fig. 1 is laminated on the surface 6a of the layered object member 6. The insulating resin film 1 has a first main surface 1a and a second main surface 1b. The first main surface 1a is opposed to the second main surface 1b. The first main surface 1a is a roughened surface. The second main surface 1b is in contact with the surface 6a of the layered object member 6. The insulating resin film 1 is used by being laminated on the surface 6a of the layered object member 6 from the second main surface 1b side.

The insulating resin film 1 contains an epoxy resin, a curing agent, and cerium oxide 2. Therefore, the dimensional change caused by heat of the cured product of the insulating resin film can be reduced. When the content of cerium oxide in 100% by weight of the entire insulating resin film is 30% by weight or more, dimensional change due to heat of the cured product of the insulating resin film can be considerably reduced.

In the insulating resin film 1, on the side of the first main surface 1a which is the roughened surface, the cerium oxide 2 is distributed in a state where it is less present than the second main surface 1b side. In the insulating resin film 1, the content of cerium oxide 2 in 100% by weight of the first region R1 having a thickness of 0.3 μm on the surface of the first main surface 1a side which is the roughened surface is less than The state of the content of the cerium oxide 2 in 100% by weight of the second region R2 other than the first region R1 causes the cerium oxide 2 to be distributed. As a result, on the first main surface 1a side, the components other than the ceria 2 in the insulating resin film 1 are distributed in a state in which the components are more present than the second main surface 1b side. In other words, the content of the component other than the cerium oxide 2 in 100% by weight of the first region R1 is more than the content of the component other than the cerium oxide 2 in 100% by weight of the second region R2. The components other than cerium oxide 2 are distributed in a biased manner. Moreover, it is preferable that the epoxy resin and the hardener in the insulating resin film 1 are distributed in a state of being more than the second main surface 1b side on the side of the first main surface 1a. Further, in the insulating resin film 1, the content of the cerium oxide 2 in 100% by weight of the second region R2 is more than 30% by weight.

In the entire insulating resin film, by dispersing the cerium oxide in the above-described state, and by disposing the components other than cerium oxide or the epoxy resin and the hardener in the above-described state, the insulation can be reduced. The dimensional change of the cured product of the resin film due to heat, and the adhesion strength between the cured product and the metal layer can be improved when a metal layer is formed on the surface of the cured product. The reason for this is considered to be that the contact area between the first main surface of the cured product and the metal layer is increased.

In the case where cerium oxide is filled at a relatively high density, cerium dioxide is also detached when the resin is etched by roughening. When the cerium oxide is filled at a relatively high density, the longer the immersion in the roughening liquid, the cerium dioxide is exposed on the surface by etching the resin, and as a result, the cerium oxide is present on the surface at a large rate. The faster the bismuth dioxide is removed. As a result, when cerium oxide is filled at a high density, since a large amount of cerium oxide exists on the surface after roughening, the surface roughness of the surface becomes large due to the unevenness of the cerium oxide, and Then the intensity can't be expressed. On the other hand, even if the cerium oxide is filled with a higher density as a whole, if the cerium oxide existing in the first region is small, the above-described situation does not occur, and the use thereof is utilized. The roughening treatment removes the resin to maintain a fine rough surface, and imparts a high bonding strength by the polarity of the resin surface and the fine anchor shape.

Further, in the epoxy resin contained in the insulating resin film, (1) the epoxy resin includes two or more kinds of first epoxy resins, and two or more of the first epoxy resins have the same structural unit. Further, the number of repetitions of the structural unit of the two or more kinds of the first epoxy resins is different (hereinafter, the entire epoxy resin used in the composition of the epoxy resin of (1) may be referred to as an epoxy resin (1). Or (2) a second epoxy resin having a carbon-carbon unsaturated bond and a third epoxy resin having no carbon-carbon unsaturated bond (hereinafter, the epoxy resin of (2) may be used hereinafter) The epoxy resin used as a whole is referred to as an epoxy resin (2)). The second epoxy resin preferably has five or more carbon-carbon unsaturated bonds and has a molecular weight of 500 or more.

In the case of using the above epoxy resin (2), microphase separation easily occurs. The reason for this is that since the second epoxy resin contains an epoxy group, compatibility with other epoxy resins or curing agents can be improved, but on the other hand, since the carbon-carbon unsaturated bond is present, the second ring is provided. The SP value (solubility parameter) of the oxygen resin tends to be low, and the difference between the SP values of other epoxy resins and curing agents tends to be large. As a result, phase separation occurs somewhat during the heat hardening process, and a fine anchor shape can be formed in the resin.

In the case where two or more kinds of the above first epoxy resins are used, the etching rate with respect to the roughening liquid can be changed by the difference in the number of repetitions of the above structural unit, and a fine anchor shape can be formed in the resin. Further, since the two or more kinds of the first epoxy resins have the same structural unit and have different numbers of repetitions of the above structural units, the compatibility of the entire resin is also good, and a fine anchor shape can be formed.

In the first region, the epoxy resin (1) or the epoxy resin (2) is likely to be microphase-separated. Further, since the content of cerium oxide in the first region is relatively small, the epoxy resin (1) or the epoxy resin (2) is likely to be microphase-separated in the first region. Therefore, the first region contains the epoxy resin (1) or the epoxy resin (2), and the content of cerium oxide in the first region is less than that in the second region. Since the content (organic component) other than cerium oxide in the first region is increased, the surface roughness of the surface of the cured product after the roughening treatment can be effectively reduced, and the cured product can be effectively improved. The strength of the bond with the metal layer.

It is preferable that the second region contains the above-described second region from the viewpoint of further reducing the surface roughness of the surface after the roughening treatment of the first region and further improving the adhesion strength between the cured material and the metal layer. Epoxy resin (1) or the above epoxy resin (2).

In order to further reduce the surface roughness of the surface after the roughening treatment and further improve the adhesion strength between the cured product and the metal layer, it is preferred that the content of the above-mentioned ceria in the first region 100% by weight is higher. The content of the above-mentioned ceria in 100% by weight of the second region is 10% by weight or more, more preferably 30% by weight or more, and still more preferably 40% by weight or more.

In order to further reduce the surface roughness of the surface after the roughening treatment, and further increase the adhesion strength between the cured product and the metal layer, and further reduce the dimensional change caused by heat of the cured product, less cerium oxide The thickness of the region (different from the first region) is preferably 0.1 μm or more, and more preferably 0.3 μm or more, regardless of the thickness of the entire insulating resin film. The thickness of the region where the cerium oxide is less (different from the first region) is preferably 5 μm or less, more preferably It is 3 μm or less. Further, the thickness of the insulating resin film is not particularly limited. In view of the trend of thinning in recent years, the thickness of the above-mentioned insulating resin film is preferably 500 μm or less, more preferably 300 μm or less. The thickness of the insulating resin film may be 5 μm or more, may be 10 μm or more, or may be 20 μm or more.

Hereinafter, each component contained in the above-mentioned insulating resin film will be described in detail.

[Epoxy resin]

In the insulating resin film, the cerium oxide is not particularly limited as long as the cerium oxide is distributed in the above-described state. As the epoxy resin, a previously known epoxy resin can be used. The above epoxy resin means an organic compound having at least one epoxy group. The epoxy resin may be used alone or in combination of two or more.

Examples of the epoxy resin include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, phenol novolak epoxy resin, biphenyl epoxy resin, and biphenol. Aldehyde 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 Epoxy resin, bismuth epoxy resin, epoxy resin containing adamantane skeleton, epoxy resin containing tricyclodecane skeleton, and containing three The core is used as a skeleton epoxy resin.

In the insulating resin film, in order to easily distribute the cerium oxide in the above state, the epoxy resin preferably contains an epoxy resin having a repeating structural unit or a roughening liquid having a pH of 12 or more. The roughening treatment produces an epoxy resin of a ketone or a carboxylic acid.

Examples of the epoxy resin having a repeating structural unit include a novolac type epoxy resin. Specific examples thereof include a naphthalene type novolac epoxy resin, a phenol aralkyl type novolac epoxy resin, a naphthol aralkyl type novolac epoxy resin, and a dicyclopentadiene type novolac epoxy resin. a novolak type epoxy resin containing a tricyclodecane skeleton, and containing three Skeleton novolac type epoxy resin, bisphenol A novolac epoxy resin and bisphenol F novolac epoxy resin.

An epoxy resin having a ketone or a carboxylic acid can be produced by a roughening treatment using a roughening liquid having a pH of 12 or more, and examples thereof include an epoxy resin having a carbon-carbon unsaturated bond. Specific examples of the commercially available product include Epolead PB3600 (manufactured by Daicel Chemical Co., Ltd.), Epolead PB4700 (manufactured by Daicel Chemical Co., Ltd.), AT501 (manufactured by Daicel Chemical Co., Ltd.), and CT310 (manufactured by Daicel Chemical Co., Ltd.).

In the insulating resin film, in order to easily distribute the cerium oxide in the above state, the epoxy resin preferably contains two or more kinds of first epoxy resins, and two or more of the first epoxy resins have the same In the structural unit, the number of repetitions of the structural unit of the two or more kinds of the first epoxy resins is different, and it is more preferable that the epoxy resin includes three or more kinds of the first epoxy resins, and three or more of the first rings The oxygen resin has the same structural unit, and the number of repetitions of the above structural unit of the three or more kinds of the above first epoxy resins is different. Preferably, the two or more kinds of the first epoxy resins and the three or more first epoxy resins have different epoxy groups. Further, it is also preferred that the epoxy resin comprises a second epoxy resin having five or more carbon-carbon unsaturated bonds and having a molecular weight of 500 or more. In the case where the insulating resin film contains the epoxy resin (1) or the epoxy resin (2), the insulating resin film may further contain a different epoxy resin (1) and the epoxy resin (2). Epoxy resin.

It is preferable that the second epoxy resin has a butadiene skeleton from the viewpoint of further reducing the surface roughness of the surface after the roughening treatment and further improving the adhesion strength between the cured product and the metal layer.

From the viewpoint of further reducing the surface roughness of the surface after the roughening treatment and further improving the adhesion strength between the cured product and the metal layer, the two or more kinds of the first epoxy resins are preferably novolac type epoxy resins. , bisphenol A type epoxy resin, biphenyl type epoxy resin, bisphenol F type epoxy resin, dicyclopentadiene type epoxy resin, or naphthalene type epoxy resin, more preferably novolak type epoxy resin , bisphenol A type epoxy resin, biphenyl type epoxy resin, bisphenol F type epoxy resin, or dicyclopentadiene type epoxy resin, and more preferably novolak type epoxy resin, biphenyl type ring An oxygen resin, a dicyclopentadiene type epoxy resin, or a naphthalene type epoxy resin. The first epoxy resin is particularly preferably a novolac type epoxy resin.

It is preferable to further reduce the surface roughness of the surface after the roughening treatment, wherein the epoxy resin includes three or more kinds of the first epoxy resins, and three or more of the first epoxy resins have the same structural unit, and In 100% by weight of the first epoxy resin, the content of the first epoxy resin in which the number of repetitions of the structural unit is 1 (the structural unit is only one and is not repeated) is 1% by weight or more, and the above structural unit is repeated. The content of the first epoxy resin is 2 or more (the number of the above-mentioned structural units is 2), and the content of the first epoxy resin is 10% by weight or more, and the number of repetitions of the structural unit is 3 or more (the structural unit is three or more) of the first epoxy resin. The content is 25% by weight or more. Preferably, the number of repetitions of the structural unit is 2 (two of the structural units), the content of the first epoxy resin is 25% by weight or more, and the number of repetitions of the structural unit is 3 or more (the above structural unit is three or more) The content of the first epoxy resin is 35% by weight or more. In this way, the number of epoxy groups in the first epoxy resin is large (the number of repeating units of the structural unit is large), and the difference in the method of removing the resin by the roughening liquid is fine. Anchor, and can exhibit higher strength.

From the viewpoint of further reducing the surface roughness of the surface after the roughening treatment and further improving the adhesion strength between the cured product and the metal layer, it is preferably 100 parts by weight of the component other than the above-mentioned ceria in the first region. In %, the content of the entire first epoxy resin (the content of the epoxy resin (1)) is 10% by weight or more and 80% by weight or less, or the component 100 other than the above-mentioned ceria in the first region. In the weight %, the total content of the second epoxy resin and the third epoxy resin (the content of the epoxy resin (2)) is 0.3% by weight or more and 30% by weight or less. From the viewpoint of further reducing the surface roughness of the surface after the roughening treatment and further improving the adhesion strength between the cured product and the metal layer, it is preferably 100 parts by weight of the component other than the above-mentioned ceria in the first region. In %, the content of the entire first epoxy resin (the content of the epoxy resin (1)) is 70% by weight or less.

In order to further reduce the surface roughness of the surface after the roughening treatment and further improve the adhesion strength between the cured product and the metal layer, it is preferable to remove the surface in the second region. The content of the entire first epoxy resin (the content of the epoxy resin (1)) is 10% by weight or more and 80% by weight or less in the second region, in 100% by weight of the component other than the cerium oxide. In 100% by weight of the components other than the cerium oxide, the total content of the second epoxy resin and the third epoxy resin (the content of the epoxy resin (2)) is 0.3% by weight or more and 30% by weight or less. From the viewpoint of further reducing the surface roughness of the surface after the roughening treatment and further improving the adhesion strength between the cured product and the metal layer, it is preferably 100 parts by weight of the component other than the above-mentioned ceria in the second region. In %, the content of the entire first epoxy resin (the content of the epoxy resin (1)) is 70% by weight or less.

The epoxy resin may be liquid at normal temperature (23 ° C) or may be solid.

The epoxy resin preferably has an epoxy equivalent of 90 or more, more preferably 100 or more, from the viewpoint of further reducing the surface roughness of the surface of the cured product and further improving the adhesion strength between the cured product and the metal layer. It is preferably 1000 or less, more preferably 800 or less. The epoxy resin preferably contains an epoxy resin having an epoxy equivalent of not less than the above lower limit and not more than the above upper limit.

The molecular weight of the above epoxy resin is preferably 1,000 or less. In this case, it is easy to increase the content of cerium oxide in the entire insulating resin film. Further, even if the content of cerium oxide is large, an insulating resin film having high fluidity can be obtained. Further, by using an epoxy resin having a weight average molecular weight of 1,000 or less and a thermoplastic resin in combination, excessive reduction in the melt viscosity of the insulating resin film can be suppressed.

The molecular weight of the epoxy resin and the molecular weight of the curing agent described below may be determined according to the case where the epoxy resin or the curing agent is not a polymer, and the structural formula of the epoxy resin or the curing agent can be determined. The molecular weight calculated from this structural formula. Further, in the case where the above epoxy resin or curing agent is a polymer, it means a weight average molecular weight.

The above weight average molecular weight means a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

[hardener]

The curing agent contained in the insulating resin film is not particularly limited. As the hardener, a previously known hardener can be used. The curing agent may be used alone or in combination of two or more.

Examples of the curing agent include a cyanate ester compound (cyanate ester curing agent), a phenol compound (phenol curing agent), an amine compound (amine curing agent), a thiol compound (thiol curing agent), and an imidazole compound. , phosphine compounds, acid anhydrides, active ester compounds and dicyandiamide. Among them, the hardener is preferably a cyanate ester compound or a phenol compound from the viewpoint of obtaining a cured product having a smaller dimensional change due to heat. The above hardener is preferably a cyanate ester compound, and is preferably a phenol compound. The above hardener preferably contains a functional group reactive with the epoxy group of the above epoxy resin.

The hardener is preferably a cyanate ester from the viewpoint of further reducing the surface roughness of the surface of the cured product, further improving the adhesion strength between the cured product and the metal layer, and forming a finer wiring on the surface of the cured product. a compound, a phenol compound or an active ester compound. Further, from the viewpoint of imparting more excellent insulation reliability to the curing agent, the above curing agent is more preferably a cyanate ester compound.

By using the cyanate ester compound, the workability of the insulating resin film having a large content of cerium oxide can be improved, and the glass transition temperature of the cured product can be further increased. The cyanate ester compound is not particularly limited. As the cyanate ester compound, a previously known cyanate ester compound can be used. The cyanate ester compound may be used alone or in combination of two or more.

Examples of the cyanate ester compound include a novolac type cyanate ester resin, a bisphenol type cyanate ester resin, and a prepolymer obtained by partially trimerating the particles. Examples of the novolak-type cyanate ester resin include a phenol novolac type cyanate ester resin and an alkylphenol type cyanate ester resin. Examples of the bisphenol-type cyanate ester resin include a bisphenol A type cyanate ester resin, a bisphenol E type cyanate ester resin, and a tetramethyl bisphenol F type cyanate ester resin.

The commercially available product of the cyanate ester compound is phenol novolac type cyanate ester resin ("PT-30" and "PT-60" manufactured by Lonza Japan Co., Ltd.), and bisphenol type cyanate. A prepolymer obtained by trimerization of an ester ester resin ("BA-230S", "BA-3000S", "BTP-1000S", and "BTP-6020S" manufactured by Lonza Japan Co., Ltd.).

The molecular weight of the cyanate ester compound is preferably 3,000 or less. In this case, the content of cerium oxide in the entire insulating resin film can be increased, and even if the content of cerium oxide is large, an insulating resin film having high fluidity can be obtained.

By using the above phenol compound, the adhesion strength between the cured product and the metal layer can be further increased. Further, by using the above phenol compound, for example, when the surface of the copper provided on the surface of the cured product is subjected to a blackening treatment or a Cz treatment, the strength of the cured product and the copper can be further increased.

The phenol compound is not particularly limited. As the phenol compound, a previously known phenol compound can be used. These phenol compounds may be used alone or in combination of two or more.

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

The commercially available product of the phenol compound may, for example, be a novolac type phenol ("TD-2091" manufactured by DIC Corporation), a biphenol novolak type phenol ("MEH-7851" manufactured by Mingwa Kasei Co., Ltd.), or an aralkyl group. Phenolic compound ("MEH-7800" manufactured by Minghe Chemical Co., Ltd.), and having an amine group III Skeleton phenol ("LA1356" and "LA3018-50P" manufactured by DIC Corporation).

The phenol compound is preferably a biphenol novolak from the viewpoint of further reducing the surface roughness of the surface of the cured product, further improving the adhesion strength between the cured product and the metal layer, and forming finer wiring on the surface of the cured product. A phenolic compound or an aralkyl type phenol compound.

From the viewpoint of further reducing the surface roughness of the surface of the cured product, it is preferred that the phenol compound has two or more phenolic hydroxyl groups.

The above-mentioned active ester compound is specifically a compound represented by the following formula (1).

R ₂ (COOR ₁ ) _k ‧‧‧式(1)

As shown in the formula (1), the above-mentioned active ester compound has an ester group which exhibits reactivity with an epoxy group, and the above-mentioned active ester compound does not generate a secondary hydroxyl group after the reaction to form a network structure.

R ₁ in the above formula (1) is a group represented by the following formula (11), (12) or (13).

In the above formulae (11) to (13), A and B each represent a halogen atom or an alkyl group, m ₁ represents 0 to 5, m ₂ represents 0 to 4, and m ₃ represents 0 to 3. In the case where A and B are plural, respectively, each of the plurality of A and B may be the same or different.

In the above formula (1), k is an integer of 2 to 4.

In the above formula (1), R ₂ is represented by the following formula (21), (22), (23), (24), (25), (26), (27), (28) or (29). The basis.

[Chemistry 7]

[11]

In the above formulae (21) to (29), D, E and G each represent a halogen atom or an alkyl group, X represents a sulfur atom, an oxygen atom, SO ₂ or Co, and n ₁ , n ₂ and n ₃ represent 0 to 4, respectively. , n ₄ and n ₅ represent 0~3, respectively, and n ₆ represents 0~2. In the case where D, E, and G are plural, respectively, each of the plurality of D, E, and G may be the same or different.

The above active ester compound is not particularly limited. As a commercial item of the above-mentioned active ester compound, "HPC-8000", "HPC-8000-65T", and "EXB9416-70BK" manufactured by DIC Corporation are mentioned.

Further reducing the surface roughness of the surface of the cured product, further improving the adhesion strength between the cured product and the metal layer, and forming finer wiring on the surface of the cured product, and imparting good insulation reliability by the hardener. In other words, it is preferred that the curing agent contains a curing agent having an equivalent weight of 250 or less. The equivalent of the above-mentioned curing agent, for example, when the curing agent is a cyanate ester compound, represents a cyanate ester group equivalent, and when the curing agent is a phenol compound, it represents a phenolic hydroxyl equivalent and is active in a hardener. In the case of an ester compound, Represents the active ester group equivalent.

The content of the curing agent having an equivalent weight of 250 or less in 100% by weight of the total amount of the curing agent is preferably 30% by weight or more, and more preferably 50% by weight or more. The above hardeners may all be hardeners having an equivalent weight of 250 or less. When the content of the curing agent having an equivalent weight of 250 or less is at least the above lower limit, the surface roughness of the surface of the cured product is further reduced, and finer wiring is formed on the surface of the insulating layer. Further, when the content of the curing agent having an equivalent weight of 250 or less is at least the above lower limit, the glass transition temperature of the cured product is further increased.

The molecular weight of the above curing agent is preferably 1,000 or less. The curing agent preferably contains a curing agent having a molecular weight of not more than the above upper limit. In this case, the content of the cerium oxide in the entire insulating resin film is 30% by weight or more, and even if it is 40% by weight or more, even if it is 50% by weight or more, an insulating resin film having high fluidity can be obtained.

The blending ratio of the epoxy resin to the hardener is not particularly limited. The blending ratio of the epoxy resin to the hardener can be appropriately determined depending on the type of the epoxy resin and the hardener. The ratio of the epoxy equivalent of the epoxy resin to the equivalent of the hardener (equivalent to epoxy equivalent: equivalent of the hardener) is preferably from 1:0.2 to 1:2, more preferably from 1:0.3 to 1:1.5. When the equivalent ratio satisfies the above range, the bonding strength between the cured product and the metal layer is further increased.

The total content of the epoxy resin and the curing agent in the total amount of the components of the insulating resin film other than cerium oxide is preferably 50% by weight or more, more preferably 70% by weight or more, and 100% by weight. % (the total amount) or less is preferably 99.9% by weight or less, more preferably 99.8% by weight or less.

[cerium oxide]

When the insulating resin film contains cerium oxide, the linear expansion ratio of the cured product can be lowered, and the surface roughness of the surface of the cured product can be effectively reduced, and the bonding strength between the cured product and the metal layer can be effectively increased. The above cerium oxide is not particularly limited. As the cerium oxide, previously known cerium oxide can be used. The above-mentioned cerium oxide may be used alone or in combination of two or more.

The viewpoint of reducing the surface roughness of the surface of the cured product, further improving the adhesion strength between the cured product and the metal layer, and forming finer wiring on the surface of the cured product, and imparting better insulation reliability to the cured product The above cerium oxide is preferably molten cerium oxide.

The average particle diameter of the above cerium oxide is preferably 1 nm or more, more preferably 10 nm or more, further preferably 50 nm or more, particularly preferably 150 nm or more, and more preferably 20 μm or less, still more preferably 10 μm or less, and further preferably 5 μm or less, particularly preferably 1 μm or less. When the average particle diameter of the cerium oxide is not less than the above lower limit and not more than the above upper limit, the size of the pores formed after the roughening treatment becomes fine, and the number of pores is appropriately increased. As a result, the bonding strength between the cured product and the metal layer is further increased.

The average particle diameter of the above-mentioned ceria is a value which is 50% of the median diameter (d50). The above average particle diameter can be measured by a particle size distribution measuring apparatus using a laser diffraction scattering method.

The above cerium oxide is preferably spherical, more preferably spherical cerium oxide. In this case, the surface roughness of the surface of the cured product is effectively reduced, and the subsequent strength of the insulating layer and the metal layer is effectively increased. Further, by using the spherical cerium oxide, the melt viscosity of the insulating resin film can be lowered, and the content of cerium oxide in the insulating resin film can be increased. When the cerium oxide is spherical, the aspect ratio of the cerium oxide is preferably 2 or less, more preferably 1.5 or less.

The above-mentioned cerium oxide is preferably subjected to surface treatment, and more preferably subjected to surface treatment by a coupling agent. Thereby, the surface roughness of the surface of the cured product is further reduced, the bonding 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 better wiring insulation is imparted to the cured product. Reliability and reliability of interlayer insulation.

Examples of the coupling agent include a decane coupling agent, a titanate coupling agent, and an aluminum coupling agent. Examples of the decane coupling agent include amino decane, imidazolium, vinyl decane, and epoxy decane.

In 100% by weight of the insulating resin film, the content of the cerium oxide is preferably 25% by weight or more, more preferably 30% by weight or more, still more preferably 35% by weight or more, and still more preferably 40% by weight or more. It is preferably 50% by weight or more, more preferably 60% by weight or more, and most preferably 95% by weight or less, more preferably 90% by weight or less, still more preferably 85% by weight or less. When the content of the cerium oxide 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 strength of the cured product and the metal layer is further increased, and the surface of the cured product is more finely formed. At the same time, if the amount of the cerium oxide is used, the linear expansion ratio of the metallic copper and the cured product can be lowered. When the content of the cerium oxide in the amount of 100% by weight of the insulating resin film is 30% by weight or more, the presence of cerium oxide located on the first main surface side and the second main surface side can be further improved. .

[thermoplastic resin]

The above insulating resin film does not contain or contain a thermoplastic resin. It is preferable that the insulating resin film contains a thermoplastic resin. The thermoplastic resin is not particularly limited. As the thermoplastic resin, a previously known thermoplastic resin can be used. The thermoplastic resin may be used alone or in combination of two or more.

Examples of the thermoplastic resin include a quinone imine resin, a phenoxy resin, a polyvinyl acetal resin, a rubber component, and an organic filler. The above thermoplastic resin is particularly preferably a phenoxy resin. By using the phenoxy resin, the dispersibility of the cerium oxide becomes good because the melt viscosity can be adjusted, and during the hardening process, the insulating resin film becomes difficult to wet and diffuse into the unintended region. Moreover, by using a thermoplastic resin, deterioration of the embedding property of the insulating resin film with respect to the hole or the unevenness of the circuit board and unevenness of the cerium oxide can be suppressed.

Examples of the phenoxy resin include a benzene having a bisphenol A type skeleton, a bisphenol F type skeleton, a bisphenol S type skeleton, a biphenyl skeleton, a novolak skeleton, a naphthalene skeleton, and a quinone imine skeleton. Oxygen resin, etc.

For example, "SOXR-C" manufactured by Japan Kodak Paper Co., Ltd., etc., may be mentioned as a commercial item of the above-mentioned quinone imine resin.

For example, "YP50", "YP55" and "YP70" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., and "1256B40", "4250" and "4256H40" manufactured by Mitsubishi Chemical Corporation are listed as the commercial products of the phenoxy resin. ", "4275", "YX6954BH30" and "YX8100BH30".

The weight average molecular weight of the thermoplastic resin is preferably 5,000 or more, and preferably 100,000 or less. It is preferable that the thermoplastic resin contains a thermoplastic resin having a weight average molecular weight of not more than the above upper limit. The above weight average molecular weight means a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

The content of the above thermoplastic resin is not particularly limited. The content of the thermoplastic resin (the content of the phenoxy resin when the thermoplastic resin is a phenoxy resin) is preferably 1% by weight or more, more preferably 5% by weight or more, and more preferably 100% by weight of the insulating resin film. It is preferably 30% by weight or less, more preferably 20% by weight or less, still more preferably 15% by weight or less. When the content of the thermoplastic resin is at least the above lower limit and not more than the above upper limit, the linear expansion ratio of the cured product is further lowered. Moreover, the embedding property of the insulating resin film with respect to the hole or the unevenness of the circuit board becomes favorable. When the content of the thermoplastic resin is at least the above lower limit, the film formability of the insulating resin film is increased, and a more excellent cured product can be obtained. When the content of the thermoplastic resin is at most the above upper limit, the surface roughness of the surface of the cured product is further reduced, and the adhesion strength between the cured product and the metal layer is further increased.

[hardening accelerator]

The insulating resin film does not contain or contain a curing accelerator. It is preferable that the insulating resin film contains a curing accelerator. By using the above-mentioned hardening accelerator, the hardening speed can be further increased. By rapidly hardening the insulating resin film, the crosslinked structure in the cured product can be made uniform, and the number of unreacted functional groups is reduced, and as a result, the crosslinking density becomes high. The hardening accelerator is not particularly limited, and a conventionally known hardening accelerator can be used. The above-mentioned hardening accelerator may be used alone or in combination of two or more.

Examples of the hardening accelerator include an imidazole compound, a phosphorus compound, and an amine. Compounds and organometallic compounds, etc.

Examples of the imidazole compound include 2-undecylimidazole, 2-heptadecylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, and 2-benzene. 4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-methyl Imidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1- Cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2 '-Methylimidazolyl-(1')]-ethyl-all three 2,4-Diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-all three 2,4-Diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-all three 2,4-Diamino-6-[2'-methylimidazolyl-(1')]-ethyl-all three Isocyanuric acid adduct, 2-phenylimidazolium isocyanurate adduct, 2-methylimidazoisocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, and 2-benzene Base-4-methyl-5-dihydroxymethylimidazole and the like.

Examples of the phosphorus compound include triphenylphosphine and the like.

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 octoate, cobalt(II) acetoacetate, and cobalt(III) triacetate.

The content of the above hardening accelerator is not particularly limited. In 100% by weight of the insulating resin film, the content of the curing accelerator is preferably 0.01% by weight or more, and preferably 3% by weight or less. When the content of the hardening accelerator is not less than the above lower limit and not more than the above upper limit, the insulating resin film can be effectively cured. When the content of the hardening accelerator is at least the above lower limit, hardening failure is more likely to occur, and a more uniform rough surface can be formed after the roughening treatment, and the strength of the cured product and the metal layer is further increased. When the content of the hardening accelerator is not more than the above upper limit, the storage stability of the insulating resin film is further improved.

[Other ingredients]

In order to improve impact resistance, heat resistance, resin compatibility, workability, and the like, a flame retardant, a coupling agent, a colorant, an antioxidant, an ultraviolet deterioration preventive agent, an antifoaming agent, and the like may be added to the insulating resin film. An adhesive, a thixotropic imparting agent, and other resins other than the above resins.

Examples of the coupling agent include a decane coupling agent, a titanium coupling agent, and an aluminum coupling agent. Examples of the decane coupling agent include vinyl decane, amino decane, imidazolium, and epoxy decane.

The content of the above coupling agent is not particularly limited. In 100% by weight of the insulating resin film, the content of the coupling agent is preferably 0.01% by weight or more, and preferably 5% by weight or less.

Examples of the other resin include a polyphenylene ether resin, a divinyl benzyl ether resin, a polyarylate resin, a diallyl phthalate resin, and a benzoate. Resin, benzo An azole resin, a bismaleimide resin, an acrylate resin, or the like.

[Other details of insulating resin film and pre-cured material]

The insulating resin film can be obtained by heating the resin composition to 60 to 140 ° C by using a resin composition containing the above epoxy resin, the above-mentioned curing agent, the above-mentioned ceria, and a solvent, and forming the film into a film shape. . Further, the first region and the second region may be formed during the drying of the above resin composition.

The above resin composition contains a solvent. By using the above solvent, the viscosity of the above resin composition can be controlled within a suitable range, and the coatability of the above resin composition can be improved. Further, the above solvent can also be used to obtain a slurry containing the above-mentioned ceria. These solvents may be used alone or in combination of two or more.

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

It is preferred that most of the above solvent is removed when the above-mentioned insulating resin film is produced. Therefore, the boiling point of the solvent is preferably 160 ° C or lower, more preferably 140 ° C or lower, further preferably 120 ° C or lower, and particularly preferably 100 ° C or lower. The above insulating resin film does not contain or contain a solvent. In the case where the insulating resin film contains a solvent, the content of the solvent in 100% by weight of the insulating resin film is preferably 5% by weight or less, more preferably 3% by weight or less, still more preferably 1% by weight or less. The content of the above solvent in the above resin composition is not particularly limited. The content of the above solvent can be appropriately changed in consideration of the coatability of the above resin composition and the like.

The method of forming the resin composition into a film shape, for example, melt-kneading and extruding the resin composition using an extruder, and then forming the film into a film shape by a T-die or a circular die. An extrusion molding method; a casting molding method in which the above resin composition containing a solvent is formed into a film shape; and other film forming methods known in the prior art. Among them, in terms of thinning, an extrusion molding method or a casting molding method is preferred, and a casting molding method is more preferred. The above film contains a sheet.

The resin composition is formed into a film shape, and is heated and dried at 90 to 200 ° C for 1 to 180 minutes to the extent that heat hardening is not excessively performed, whereby the above-mentioned insulating resin film can be obtained. The insulating resin film of the present invention may be an insulating resin film before pre-curing, or may be an insulating resin film after pre-curing. In the pre-hardened insulating resin film, it is preferable that the content of the cerium oxide in 100% by weight of the first region is less than the cerium oxide in 100% by weight of the second region other than the first region. In the state of the content, the cerium oxide is distributed in a biased manner, and the content of the cerium oxide in 100% by weight of the second region is more than 30% by weight.

The insulating resin film which can be obtained by the drying step as described above is referred to as a B-stage film. The insulating resin film is a semi-cured material in a semi-hardened state. The semi-hardened material is not completely hardened and can be further hardened.

It is preferable that the above-mentioned insulating resin film is not a preform. When the insulating resin film is not a preform, migration does not occur along the glass cloth or the like. Further, when the insulating resin film is laminated or pre-hardened, irregularities caused by the glass cloth are not generated on the surface.

The insulating resin film can be used in a state in which a laminated film on one surface of a substrate is laminated. The laminated film includes the substrate and the insulating resin film laminated on one surface of the substrate.

The base material of the laminated film may be a polyester resin film such as a polyethylene terephthalate film or a polybutylene terephthalate film, an olefin resin film such as a polyethylene film or a polypropylene film, or a poly A metal foil such as a ruthenium imide resin film, a copper foil or an aluminum foil. The surface of the above substrate may also be subjected to a mold release treatment as needed.

In the case where the above-mentioned insulating resin film is used as the insulating layer of the circuit, the thickness of the insulating layer formed of the insulating resin film is preferably equal to or greater than the thickness of the conductor layer (metal layer) forming the circuit. The thickness of the insulating layer formed of the insulating resin film is preferably 5 μm or more, and preferably 200 μm or less.

The pre-cured material subjected to the roughening treatment can be obtained by subjecting the first main surface of the insulating resin film to a roughening treatment. In the case where the insulating resin film is an insulating resin film before pre-curing, it is preferable to obtain a roughening treatment by roughening the first main surface after curing the insulating resin film. Hardened material. The first main surface of the insulating resin film is subjected to a swelling treatment, and after the swelling treatment, the roughening treatment is performed to obtain a pre-cured product which is subjected to a swelling treatment and a roughening treatment. In order to form fine unevenness on the surface of the pre-cured material, it is preferred that the pre-cured material is subjected to a swelling treatment before the roughening treatment. It is preferable that the pre-cured material is subjected to a swelling treatment after pre-hardening and before the roughening treatment. However, the pre-cured material may not necessarily be subjected to swelling treatment. In the insulating resin film, the swelling treatment and the roughening treatment are performed on the first main surface.

In order to obtain the above-mentioned pre-hardened insulating resin film, it is preferable that the insulating resin film before pre-hardening is laminated on the laminated object member by laminating from the second main surface side. Thereafter, the insulating resin film before the pre-hardening is cured. The lamination temperature is preferably 55 ° C or higher, more preferably 65 ° C or higher, and is preferably 130 ° C or lower, more preferably 120 ° C or lower. The lamination pressure is preferably 0.5 MPa or more, more preferably 0.8 MPa or more, and is preferably 1.5 MPa or less, more preferably 1.2 MPa or less.

A method of laminating the insulating resin film before the pre-hardening by lamination may be a known method, and is not particularly limited. For example, the insulating resin film before the pre-hardening is laminated on a laminated object member such as a circuit board, and pressurized by a pressure laminator. At this time, heating may or may not be performed. Next, the laminated object member and the insulating resin film before the pre-hardening are heated and pressurized by a parallel plate pressing type heating press. The insulating resin film before the pre-hardening is pre-cured by heating and pressurization to form an insulating resin film which is pre-cured. The temperature of the heating and the pressure of the pressurization can be appropriately changed, and are not particularly limited.

Preferably, the insulating resin film before the pre-hardening is laminated on the layered member, and then heat-treated at 160 to 200 ° C for 20 minutes to 180 minutes. The insulating resin film before the pre-hardening is pre-cured by heat treatment to obtain an insulating resin film which is pre-cured. In the case of using the above laminated film, the substrate of the laminated film may be removed before the pre-cured insulating resin film is formed, or may be removed after the pre-cured insulating resin film is formed. By performing the roughening treatment after laminating under such conditions, the roughened pre-cured material can be obtained, and fine irregularities can be formed on the surface of the pre-cured material. The pre-cured material is preferably hardened at a temperature 10 to 60 ° C lower than the glass transition temperature of the final cured product.

The parallel plate heating press may be carried out after the roll lamination as needed to improve the smoothness of the surface of the pre-cured insulating resin film. For example, a parallel plate heating press can be used to heat and press the laminate of the above-mentioned laminated object member and the above-mentioned pre-hardened insulating resin film with a stainless steel plate having a thickness of 1 mm.

Furthermore, as a pressure laminating machine such as a heat and pressure roll laminator, and a parallel plate addition A press such as a hot press can be used as a commercially available device. The layering by the roll laminator is preferably carried out under vacuum. The material of the roller of the roll laminator can be appropriately selected from the case of a rubber roller having a soft surface and a metal roller having a hard surface. The flat plate of the parallel plate heating press is made of a hard metal.

A film having a mold release function can be used between the roll of the roll laminator, the laminated object member, the insulating resin film, or the flat plate of the parallel plate heating press, the laminated object member, and the insulating resin film. For example, an aluminum foil, a copper foil, a polyester resin film, a fluororesin film, or the like.

In order to improve the adhesion between the laminated object member and the insulating resin film, a material having flexibility such as a rubber sheet can be used.

In the step of forming the pre-cured insulating resin film, the insulating resin film before the pre-hardening is laminated on the laminated object member from the second main surface side, and is pressurized by a roll laminator. The parallel plate pressing type heating press performs heating and pressurization to form a pre-hardened insulating resin film. Further, in the case of using the above laminated film, it is preferred to pressurize after using a roll laminator and before heating and pressurizing using a parallel plate press type heating press, or pressurizing using a roll laminator Thereafter, the substrate was removed after heating and pressurization using a parallel plate press type heating press.

The laminate of the present invention includes a cured product obtained by curing a pre-cured material obtained by subjecting the first main surface of the insulating resin film to a roughening treatment to harden the pre-cured material; and a metal a layer laminated on the roughened surface of the cured product. The bonding strength between the cured product and the metal layer is preferably 4.9 N/cm or more, more preferably 5.9 N/cm or more. The metal layer is preferably a copper layer, more preferably a copper plating layer.

(printed wiring board)

The above insulating resin film can be preferably used for forming an insulating layer on a printed wiring board. The printed wiring board can be obtained, for example, by heating and press-molding the above-mentioned insulating resin film.

For the above insulating resin film, a metal foil can be laminated on one side or both sides. On the layer The method of the insulating resin film and the metal foil is not particularly limited, and a known method can be employed. For example, the insulating resin film may be laminated on the metal foil by heating or while pressing without heating in a device such as a parallel plate press or a roll laminator.

(copper foil laminate and multilayer substrate)

The above insulating resin film can be preferably used for obtaining a copper foil laminate. An example of the copper foil laminate is a copper foil laminate including a copper foil and the insulating film laminated on one surface of the copper foil.

The thickness of the copper foil of the copper foil laminate is not particularly limited. The thickness of the copper foil is preferably 1 μm or more, and preferably 50 μm or less. Further, in order to increase the adhesion strength between the cured product (insulating layer) and the copper foil obtained by curing the insulating resin film, it is preferable that the copper foil has fine irregularities on the surface. The method of forming the unevenness is not particularly limited. Examples of the method for forming the unevenness include a method of forming a treatment using a known chemical liquid, and the like.

Further, the above insulating resin film can be preferably used for obtaining a multilayer substrate. An example of the multilayer substrate is a multilayer substrate including a circuit board and an insulating layer laminated on the surface of the circuit board. The insulating layer of the multilayer substrate is formed by subjecting the insulating resin film to a roughening treatment and curing. Preferably, the insulating layer is laminated on a surface of the circuit substrate on which the circuit is provided. Preferably, one of the insulating layers is partially 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 board is laminated is roughened. The roughening treatment method may be a conventionally known roughening treatment method, and is not particularly limited. The surface of the above insulating layer may be subjected to a swelling treatment before the roughening treatment.

Further, it is preferable that the multilayer substrate further includes a copper plating layer laminated on the roughened surface of the insulating layer.

Further, as another example of the multilayer substrate, an insulating layer including a circuit board, a layer laminated on a surface of the circuit board, and a laminate layer formed on the insulating layer may be used. A multilayer substrate of copper foil on the surface opposite to the surface of the circuit substrate. Preferably, in the insulating layer and the copper foil, the insulating resin film is roughened by using a copper foil laminate including a copper foil and an insulating resin film laminated on one surface of the copper foil. Formed by hardening. Further, the copper foil is preferably etched and is a copper circuit.

As another example of the multilayer substrate, a multilayer substrate including a circuit board and a plurality of insulating layers laminated on the surface of the circuit board can be cited. At least one of the plurality of insulating layers disposed on the circuit board is formed by subjecting the insulating resin film to a roughening treatment and curing. It is preferable that the multilayer substrate further includes a circuit laminated on at least one surface of the insulating layer formed by roughening and hardening the insulating resin film.

In Fig. 2, a multilayer substrate in which an insulating resin film according to an embodiment of the present invention is used is schematically shown in a front cross-sectional view of a partial slit.

In the multilayer substrate 11 shown in FIG. 2, a plurality of insulating layers 13 to 16 are laminated on the upper surface 12a of the circuit substrate 12. The insulating layers 13 to 16 are insulating layers. A metal layer 17 is formed in a partial region of the upper surface 12a of the circuit substrate 12. Among the plurality of insulating layers 13 to 16, the insulating layers 13 to 15 other than the insulating layer 16 on the surface opposite to the side on the side opposite to the circuit board 12 are formed with a metal layer 17 in a partial region of the upper surface. Metal layer 17 is an electrical circuit. The metal layer 17 is disposed between the circuit board 12 and the insulating layer 13 and between the respective layers of the insulating layers 13 to 16 of the stacked layers. The lower metal layer 17 and the upper metal layer 17 are connected to each other by at least one of a via connection and a via connection (not shown).

In the multilayer substrate 11, the insulating layers 13 to 16 are formed by roughening and hardening the insulating resin film of the present invention. Further, in Fig. 2, the insulating layers 13 to 16 are shown in a schematic view. In the present 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. Further, in the multilayer substrate 11, the dimension (L) in the width direction of the metal layer 17 and the dimension (S) in the width direction of the portion in which the metal layer 17 is not formed can be reduced. Further, in the multilayer substrate 11, good insulation reliability is imparted between the metal layer which is not connected by the via connection and the via connection (not shown) and the underlying metal layer.

(roughening and swelling treatment)

As a method of the swelling treatment, for example, a method of treating an insulating resin film with an aqueous solution of a compound containing a main component such as ethylene glycol or an organic solvent dispersion can be used. The swelling liquid used in the swelling treatment generally contains a base as a pH adjuster or the like. Preferably, the swelling liquid contains sodium hydroxide. Specifically, for example, the swelling treatment is carried out by treating the cured product at a treatment temperature of 30 to 85 ° C for 1 to 30 minutes by using a 40% by weight aqueous solution of ethylene glycol or the like. The temperature of the above swelling treatment 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 subsequent strength of the cured product and the metal layer tends to be low.

At the time of the above roughening treatment, for example, a chemical oxidizing agent such as a manganese compound, a chromium compound or a persulfate compound can be used. The chemical oxidizing agents may be used in the form of an aqueous solution or an organic solvent dispersion after adding water or an organic solvent. The roughening liquid used in the roughening treatment generally contains a base as a pH adjuster or the like. Preferably, the roughening liquid 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 persulfuric acid compound include sodium persulfate, potassium persulfate, and ammonium persulfate.

The method of the above roughening treatment is not particularly limited. As a method of the above roughening treatment, for example, it is preferred to use 30-90 g/L permanganic acid or permanganate solution and 30-90 g/L sodium hydroxide solution at a treatment temperature of 30 to 85 ° C and 1 to 30 minutes. A method of treating a cured product under the conditions. The roughening treatment is preferably carried out once or twice. The temperature of the above roughening treatment is preferably in the range of 50 to 85 °C.

The arithmetic mean roughness Ra of the surface of the cured product is preferably 20 nm or more, and preferably 200 nm or less. In this case, the bonding strength between the cured product and the metal layer or the wiring becomes high, and further finer wiring is formed on the surface of the insulating layer.

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

(thermosetting resin)

Bisphenol A type epoxy resin (corresponding to the above third epoxy resin, "RE410S" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 178)

The biphenyl type epoxy resin 1 (only the biphenyl type epoxy resin 1 corresponds to the above first epoxy resin, and corresponds to the above third epoxy resin, "NC3000" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 275)

The biphenyl type epoxy resin 2 (only the biphenyl type epoxy resin 2 corresponds to the above first epoxy resin, and corresponds to the above third epoxy resin, "NC3000H" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 288)

* The combination of biphenyl type epoxy resin 1 and biphenyl type epoxy resin 2 also corresponds to two or more of the above first epoxy resins.

Epoxy resin 1 containing a rubber skeleton (only the first epoxy resin corresponding to the epoxy resin containing a rubber skeleton, and corresponding to the second epoxy resin, "AT-501" manufactured by Daicel Chemical Co., Ltd., ring Oxygen equivalent 1054, containing styrene-butadiene skeleton)

Epoxy resin 2 containing a rubber skeleton (corresponding to the first epoxy resin in the case of an epoxy resin containing a rubber skeleton, and corresponding to the second epoxy resin, "PB3600" manufactured by Daicel Chemical Co., Ltd., epoxy equivalent 200, containing butadiene skeleton)

(hardener)

Amine-based a solution of a skeleton cresol novolac hardener ("LA3018-50P" manufactured by DIC Corporation, equivalent 151, content of solid content is 50% by weight, and content of propylene glycol monomethyl ether is 50% by weight)

(hardening accelerator)

Imidazole compound ("2P4MZ" manufactured by Shikoku Chemicals Co., Ltd.)

(cerium oxide)

a slurry containing cerium oxide ("SC2050HNK" manufactured by Admatechs Co., Ltd., the average particle diameter of cerium oxide is 0.5 μm, and the cerium oxide is surface-treated with an amino decane, and the content of cerium oxide is 70% by weight. The content of cyclohexanone is 30% by weight)

(thermoplastic resin)

A solution containing a quinone imine resin ("SOXR-C" manufactured by Japan Kotami Paper Co., Ltd., the content of the solid content is 20% by weight, and the content of cyclopentanone is 80% by weight)

(Example 1)

13.3 parts by weight of a biphenyl type epoxy resin 1 ("NC3000" manufactured by Nippon Kayaku Co., Ltd.), 1.5 parts by weight of an epoxy resin 1 ("AT-501" manufactured by Daicel Chemical Co., Ltd.) containing a rubber skeleton, and an amine group. three 10 parts by weight of a solution of the skeleton cresol novolak curing agent ("LA3018-50P" manufactured by DIC Corporation) (5 parts by weight based on the solid content), and an imidazole compound ("2P4MZ" manufactured by Shikoku Kasei Co., Ltd.) 0.1 weight 69.9 parts by weight of a slurry containing cerium oxide ("SC2050HNK" manufactured by Admatech Co., Ltd.) (48.9 parts by weight based on the solid content), and a solution containing a quinone imine resin (manufactured by Japan Kotami Paper Co., Ltd.) 5.2 parts by weight (1 part by weight of the solid content) of the SOXR-C") was mixed, and the mixture was stirred at normal temperature until it became a homogeneous solution, and the resin composition was obtained.

A transparent polyethylene terephthalate (PET) film ("PET5011" manufactured by Lintec Co., Ltd., thickness: 50 μm) which was subjected to release treatment was prepared. On the release-treated surface of the PET film, the obtained resin composition was applied by a die coater so as to have a thickness of 50 μm after drying, and then dried at 60 to 120 ° C to obtain a pre-hardened surface. Insulating resin film. Then, the first PET film ("PET T60" manufactured by Toray Industries, Ltd., thickness: 38 μm) was thermally laminated on the surface of the pre-cured insulating resin film at 60 ° C to obtain a laminated film. In the laminated film, the insulating resin film before pre-curing has a second main surface on the second PET film (PET 5011) side, and the first roughened surface on the first PET film (PET T60) side. Main face.

Fabrication of a laminate comprising a pre-hardened insulating resin film

After peeling off the second PET film, the second film surface of the insulating resin film before pre-hardening is placed on the epoxy glass substrate (FR-4, "CS-3665" manufactured by Lichang Industrial Co., Ltd.). )on. The laminated body including the epoxy glass substrate, the pre-hardened insulating resin film, and the first PET film was laminated pressure using a vacuum pressure laminating machine ("MVLP-500" manufactured by Nihon Seisakusho Co., Ltd.). 0.5 MPa and a laminating temperature of 70 ° C were subjected to pressure heating for 20 seconds, and further subjected to pressure heating at a pressing pressure of 1 MPa and a pressing temperature of 90 ° C for 40 seconds to obtain a glass-impregnated substrate, pre-hardened. The insulating resin film and the laminated body of the first PET film. Thereafter, the first PET film was peeled off, and pre-curing was performed in an oven at 140 ° C for 30 minutes. Thus, the laminated body A of the epoxy glass substrate and the pre-hardened insulating resin film was obtained. The obtained pre-cured insulating resin film has a second main surface on the side of the epoxy glass substrate, and has a first main surface which is a roughened surface on the side opposite to the epoxy glass substrate.

(Examples 2 to 15 and Comparative Examples 1 and 2)

A resin composition, a first and second PET film, and a pre-hardened layer were obtained in the same manner as in Example 1 except that the types and the amounts of the components to be used were changed as shown in the following Tables 1 to 3. The laminated film of the former insulating resin film and the laminated body A containing the epoxy glass substrate and the pre-hardened insulating resin film.

(Evaluation)

(1) The existence state of cerium oxide

With respect to the obtained laminate A, a cross-sectional observation of the pre-hardened insulating resin film was performed. The existence state 1 of the cerium oxide in the pre-hardened insulating resin film was determined by the following criteria. Further, the state of presence of cerium oxide in the pre-hardened insulating resin film coincides with the state of presence of cerium oxide in the insulating resin film before pre-hardening.

[Determination criteria for the presence of cerium oxide 1]

A: the thickness of the surface portion of the first main surface side which is the roughened surface is 0.3 μm The content of cerium oxide in 100% by weight of the first region is less than the content of cerium oxide in 100% by weight of the second region other than the first region, and the cerium oxide is distributed to the surface.

B: Does not meet the criteria for A

(2) The existence state of cerium oxide in the first and second regions

The obtained insulating resin film before pre-hardening was subjected to coarsening by SEM-EDX analysis (scanning electron microscope-energy dispersive X-ray analysis). The surface to be treated is the content of cerium oxide in the first region having a thickness of 0.3 μm on the surface of the first main surface side, and the content of cerium oxide in the second region other than the first region. Further, the presence of cerium oxide in the first and second regions in the insulating resin film before pre-hardening and the presence of cerium oxide in the first and second regions in the insulating resin film after pre-curing Consistent.

(3) Average linear expansion ratio

The obtained insulating resin film was heated at 190 ° C for 3 hours to be hardened to obtain a cured product A. The obtained cured product A was cut into a size of 3 mm × 25 mm. Using a linear expansion ratio meter ("TMA/SS120C" manufactured by Seiko Instruments Co., Ltd.), the cut cured product was measured at 25 to 150 under the conditions of a tensile load of 3.3 × 10 ^-2 N and a heating rate of 5 ° C / min. The average linear expansion ratio at °C. The average linear expansion ratio was judged by the following criteria.

[Criteria for determining the average linear expansion rate]

○○: 25ppm or less

○: more than 25 ppm and less than 40 ppm/°C

×: more than 40ppm/°C

(4) Arithmetic mean roughness Ra

After the pre-hardened insulating resin film in the layered product A is subjected to the following (a) swelling treatment, the following (b) permanganate treatment, that is, a roughening treatment, is performed.

(a) Swelling treatment:

The laminate A was placed in a swelling solution ("Swelling Dip Securiganth P" manufactured by Atotech Japan Co., Ltd.) at 60 ° C and shaken for 20 minutes. Thereafter, it is washed with pure water.

(b) Permanganate treatment:

The layered product was placed in a roughened aqueous solution of potassium permanganate ("Concentrate Compact CP" manufactured by Atotech Japan Co., Ltd.) at 80 ° C, and shaken for 20 minutes to obtain a roughened pre-cured product on a glass substrate. The pre-cured product obtained was washed with a 23 ° C cleaning solution ("Reduction Securiganth P" manufactured by Atotech Japan Co., Ltd.) for 2 minutes, and then further washed with pure water.

Thereafter, the arithmetic mean roughness Ra of the roughened surface of the pre-cured material was measured in accordance with JIS B0601-1994. The arithmetic mean roughness Ra is determined by the following criteria.

[Determination of Arithmetic Mean Roughness Ra]

○: 20 nm or more and 200 nm or less

×: less than 20 nm or more than 200 nm

(5) Subsequent strength (peel strength)

After the evaluation of the above (4) arithmetic mean roughness Ra, the roughened pre-cured material on the epoxy glass substrate was subjected to the following (c) copper plating treatment.

(c) Copper plating:

The surface of the pre-cured material was treated with an alkali cleaning solution (Cleaner Securiganth 902, manufactured by Atotech Japan Co., Ltd.) at 60 ° C for 5 minutes, and degreased and washed. After washing, the pre-cured material was treated with a prepreg at 25 ° C ("Pre-dip Neoganth B" manufactured by Atotech Japan Co., Ltd.) for 2 minutes. Thereafter, the pre-cured material was treated with an activator solution (Activator Neoganth 834) manufactured by Atotech Japan Co., Ltd. at 40 ° C for 5 minutes, and a palladium catalyst was added thereto. Next, the pre-cured material was treated for 5 minutes using a reducing solution ("Reducer Neoganth WA" manufactured by Atotech Japan Co., Ltd.) at 30 °C.

Next, the pre-cured material is added to a chemical copper liquid (manufactured by Atotech Japan) In "Basic Printganth MSK-DK", "Copper Printganth MSK", "Stabilizer Printganth MSK" and "Reducer Cu", electroless plating is performed until the plating thickness is about 0.5 μm. After electroless plating, in order to remove residual hydrogen, annealing was performed at a temperature of 120 ° C for 30 minutes. All the steps up to the electroless plating step were carried out while shaking the pre-cured material while setting the treatment liquid to 2 L on a beaker scale.

Next, the pre-cured material subjected to the electroless plating treatment was subjected to electrolytic plating until the plating thickness became 25 μm. Copper sulphate solution ("copper sulphate pentoxide" manufactured by Wako Pure Chemical Industries, Ltd., "Sulfuric acid" manufactured by Wako Pure Chemical Industries, Ltd., "Basic Leveler Cupracid HL" manufactured by Atotech Japan Co., Ltd., Atotech Japan The company's "corrector Cupracid GS") is supplied with a current of 0.6 A/cm ² . After the copper plating treatment, the pre-cured material was heated at 190 ° C for 90 minutes to be hardened to obtain a cured product in which a copper plating layer was formed.

[Method of measuring the strength]

A slit having a width of 10 mm was cut out on the surface of the copper plating layer on which the hardened layer of the copper plating layer was formed. Then, the tensile strength (peeling strength) of the copper plating layer and the cured product was measured under the conditions of a crosshead speed of 5 mm/min using a tensile tester ("Autograph" manufactured by Shimadzu Corporation). The subsequent strength was judged by the following criteria.

[Subsequent strength criteria]

○○: 5.9 N/cm or more

○: 4.9 N/cm or more and less than 5.9 N/cm

×: not up to 4.9 N/cm

The results are shown in Tables 1 to 3 below.

1‧‧‧Insulating resin film

1a‧‧‧1st main face

1b‧‧‧2nd main face

2‧‧‧2 cerium oxide

6‧‧‧Multilayer object components

6a‧‧‧ surface

R1‧‧‧1st area

R2‧‧‧2nd area

Claims (10)

An insulating resin film which is subjected to a roughening treatment and has a first main surface and a second main surface, wherein the first main surface is a roughened surface, and contains an epoxy resin, a hardener, and two In the cerium oxide, the content of the cerium oxide in the 100% by weight of the first region having a thickness of 0.3 μm on the surface of the first main surface side, which is the roughened surface, is less than the second portion other than the first region. The cerium oxide is distributed in a state in which the content of the cerium oxide in the region of 100% by weight is distributed, and the content of the cerium oxide in 100% by weight of the second region is more than 30% by weight. The insulating resin film according to claim 1, wherein the content of the above-mentioned ceria in 100% by weight of the second region is more than 60% by weight. The insulating resin film according to claim 1 or 2, wherein the content of the cerium oxide in 100% by weight of the first region is 10% by weight or more lower than the content of the cerium oxide in 100% by weight of the second region. The insulating resin film according to claim 1 or 2, wherein the epoxy resin comprises two or more first epoxy resins, and the two or more first epoxy resins have the same structural unit, and two or more of the above The epoxy resin has a different number of repeating units of the above structural unit, or the epoxy resin includes a second epoxy resin having a carbon-carbon unsaturated bond and a third epoxy resin having no carbon-carbon unsaturated bond. The insulating resin film according to claim 1 or 2, wherein the content of the cerium oxide is 30% by weight or more and 85% by weight or less based on 100% by weight of the entire insulating resin film. The insulating resin film of claim 5, wherein the content of the cerium oxide is 60% by weight or more and 85% by weight or less based on 100% by weight of the entire insulating resin film. The insulating resin film according to claim 1 or 2, wherein the first main surface is subjected to a swelling treatment and is subjected to a roughening treatment after the swelling treatment. A pre-cured material obtained by subjecting the first main surface of the insulating resin film of claim 1 or 2 to a roughening treatment. A laminate comprising: a cured product which can be obtained by using a pre-cured product obtained by subjecting the first main surface of the insulating resin film of claim 1 or 2 to a roughening treatment to obtain a pre-cured product Obtained by hardening; and a metal layer laminated on the roughened surface of the hardened material. A multilayer substrate comprising: a circuit board; and an insulating layer disposed on the circuit board, wherein the insulating layer is formed by roughening and hardening the insulating resin film according to claim 1 or 2.