阅读说明：本技术 树脂材料、叠层结构体及多层印刷布线板 (Resin material, laminated structure, and multilayer printed wiring board ) 是由 川原悠子 林达史 久保显纪子 竹田幸平 新土诚实 胁冈彩香 大当悠太 新井祥人 于 2019-08-27 设计创作，主要内容包括：本发明的目的在于提供一种树脂材料,其1)可提高蚀刻后的表面粗糙度的均一性、2)可提高固化物的热尺寸稳定性、3)可提高镀敷剥离强度、4)可提高对凹凸表面的嵌埋性、5)可抑制层压时从基板周围的过度伸出。本发明的树脂材料,其包含具有源自二聚物二胺的骨架或源自三聚物三胺的骨架的马来酰亚胺化合物,所述马来酰亚胺化合物的玻璃化转变温度为80℃以上。(The purpose of the present invention is to provide a resin material which 1) can improve the uniformity of surface roughness after etching, 2) can improve the thermal dimensional stability of a cured product, 3) can improve the plating peel strength, 4) can improve the embeddability into an uneven surface, and 5) can suppress excessive protrusion from the periphery of a substrate during lamination. The resin material of the present invention comprises a maleimide compound having a skeleton derived from dimer diamine or a skeleton derived from trimer triamine, and the maleimide compound has a glass transition temperature of 80 ℃ or higher.)

1. A resin material comprising a maleimide compound having a skeleton derived from a dimer diamine or a skeleton derived from a trimer triamine,

the maleimide compound has a glass transition temperature of 80 ℃ or higher.

2. The resin material according to claim 1, wherein the maleimide compound has a weight-average molecular weight of 1000 or more and 50000 or less.

3. The resin material according to claim 2, wherein the weight average molecular weight of the maleimide compound is 3000 or more and 30000 or less.

4. The resin material according to any one of claims 1 to 3, wherein the maleimide compound is a citraconimide compound.

5. The resin material according to any one of claims 1 to 4, wherein the maleimide compound has the skeleton derived from dimer diamine or the skeleton derived from trimer triamine at both ends of a main chain.

6. The resin material according to any one of claims 1 to 5, wherein the maleimide compound has the skeleton derived from dimer diamine or the skeleton derived from trimer triamine only at both ends of a main chain.

7. The resin material according to any one of claims 1 to 6, wherein the maleimide compound has a skeleton derived from a reactant of a diamine compound other than dimer diamine and acid dianhydride at a portion other than both ends of a main chain.

8. The resin material according to any one of claims 1 to 7, comprising a maleimide compound having no skeleton derived from a dimer diamine.

9. The resin material according to claim 8, wherein the maleimide compound having no skeleton derived from dimer diamine comprises an N-phenylmaleimide compound.

10. The resin material according to any one of claims 1 to 9, which contains an inorganic filler,

the content of the inorganic filler is 50 wt% or more based on 100 wt% of components other than the solvent in the resin material.

11. The resin material according to claim 10, wherein the inorganic filler has an average particle diameter of 1 μm or less.

12. The resin material according to claim 10 or 11, wherein the inorganic filler material is silicon oxide.

13. The resin material according to any one of claims 1 to 12, comprising an epoxy compound, and

and a curing agent containing at least 1 component selected from phenol compounds, cyanate ester compounds, acid anhydrides, active ester compounds, carbodiimide compounds and benzoxazine compounds.

14. The resin material according to claim 13, wherein the curing agent comprises the benzoxazine compound,

the benzoxazine compound has a skeleton derived from dimer diamine.

15. The resin material according to any one of claims 1 to 14, comprising a curing accelerator,

the curing accelerator comprises an anionic curing accelerator.

16. The resin material according to claim 15, wherein the content of the anionic curing accelerator is 20% by weight or more based on 100% by weight of the curing accelerator.

17. The resin material according to any one of claims 1 to 16, which is a resin film.

18. A laminated structure comprising: a lamination object member having a metal layer on a surface thereof, and a resin film laminated on the surface of the metal layer, and

the resin film is the resin material according to any one of claims 1 to 17.

19. The laminated structure as claimed in claim 18, wherein the material of the metal layer is copper.

20. A multilayer printed wiring board, comprising: a circuit board,

A plurality of insulating layers disposed on the surface of the circuit board, and

a metal layer disposed between the plurality of insulating layers,

at least one of the insulating layers is a cured product of the resin material according to any one of claims 1 to 17.

Technical Field

The present invention relates to a resin material containing a maleimide compound. The present invention also relates to a multilayer structure and a multilayer printed wiring board using the resin material.

Background

Various resin materials have been used for obtaining electronic parts such as semiconductor devices, laminates, and printed wiring boards. For example, a resin material is used for forming an insulating layer for insulating an internal interlayer or an insulating layer located in a surface layer portion in a multilayer printed wiring board. A wiring as a metal is usually laminated on the surface of the insulating layer. In addition, a resin film obtained by forming the resin material into a film may be used for forming the insulating layer. The resin material and the resin film can be used as an insulating material for a multilayer printed wiring board including a build-up film, and the like.

Patent document 1 listed below discloses a resin composition containing a compound having a maleimide group, a divalent group having at least 2 imide bonds, and a saturated or unsaturated divalent hydrocarbon group. Patent document 1 describes that a cured product of the resin composition can be used as an insulating layer of a multilayer printed wiring board or the like.

Patent document 2 below discloses a resin composition for electronic materials, which contains a bismaleimide compound having 2 maleimide groups and 1 or more polyimide groups having a specific structure. In the bismaleimide compound, 2 maleimide groups are independently bonded to both ends of the polyimide group via a first linking group in which at least 8 atoms are linearly linked.

Documents of the prior art

Patent document

Patent document 1: WO2016/114286A1

Patent document 2: japanese patent laid-open publication No. 2018-90728

Disclosure of Invention

Problems to be solved by the invention

When the insulating layer is formed using the conventional resin material described in patent documents 1 and 2, the thermal dimensional stability may not be sufficiently improved, or the surface roughness after etching may be uneven. When the surface roughness after etching is uneven, the strength of the insulating layer is not sufficiently improved because the resin contributing to the anchor effect is locally thinned, and the plating peel strength between the cured product (insulating layer) after etching and the metal layer laminated on the surface of the insulating layer by plating may not be sufficiently improved.

In addition, when the insulating layer is formed using a conventional resin material such as that described in patent document 1, or when the insulating layer is formed using a conventional resin material containing an epoxy resin, the embeddability of the resin material with respect to irregularities of the substrate or the like may not be sufficiently improved, or the resin material may excessively protrude from the periphery of the substrate during lamination, which may make it difficult to control the film thickness.

The purpose of the present invention is to provide a resin material which (1) can improve the uniformity of surface roughness after etching, 2) can improve the thermal dimensional stability of a cured product, 3) can improve the plating peel strength, 4) can improve embeddability into an uneven surface, and (5) can suppress excessive protrusion from the periphery of a substrate during lamination. Another object of the present invention is to provide a multilayer structure and a multilayer printed wiring board using the resin material.

Means for solving the problems

According to a broad aspect of the present invention, there is provided a resin material comprising a maleimide compound having a skeleton derived from dimer diamine or a skeleton derived from trimer triamine, and the maleimide compound having a glass transition temperature of 80 ℃ or more.

In a specific aspect of the resin material of the present invention, the maleimide compound has a weight-average molecular weight of 1000 or more and 50000 or less.

In a specific aspect of the resin material of the present invention, the maleimide compound has a weight-average molecular weight of 3000 to 30000.

In a specific aspect of the resin material of the present invention, the maleimide compound is a citraconimide compound.

In a specific aspect of the resin material of the present invention, the maleimide compound has the skeleton derived from dimer diamine or the skeleton derived from trimer triamine at both ends of the main chain.

In a specific aspect of the resin material of the present invention, the maleimide compound has the skeleton derived from dimer diamine or the skeleton derived from trimer triamine only at both ends of the main chain.

In a specific aspect of the resin material of the present invention, the maleimide compound has a skeleton derived from a reactant of a diamine compound other than dimer diamine and acid dianhydride at a portion other than both ends of a main chain.

In a certain specific aspect of the resin material of the present invention, the resin material contains a maleimide compound having no skeleton derived from a dimer diamine.

In a specific aspect of the resin material of the present invention, the maleimide compound having no skeleton derived from dimer diamine comprises an N-phenylmaleimide compound.

In a specific aspect of the resin material of the present invention, the resin material contains an inorganic filler, and the content of the inorganic filler is 50% by weight or more based on 100% by weight of components other than the solvent in the resin material.

In a specific aspect of the resin material of the present invention, the inorganic filler has an average particle diameter of 1 μm or less.

In a specific aspect of the resin material of the present invention, the inorganic filler is silicon oxide.

In a specific aspect of the resin material of the present invention, the resin material includes an epoxy compound and a curing agent containing at least 1 component of a phenol compound, a cyanate ester compound, an acid anhydride, an active ester compound, a carbodiimide compound, and a benzoxazine compound.

In a certain specific aspect of the resin material of the present invention, the curing agent contains the benzoxazine compound having a skeleton derived from dimer diamine.

In a specific aspect of the resin material of the present invention, the resin material contains a curing accelerator containing an anionic curing accelerator.

In a specific aspect of the resin material of the present invention, the content of the anionic curing accelerator is 20% by weight or more based on 100% by weight of the curing accelerator.

In a specific aspect of the resin material of the present invention, the resin material is a resin film.

According to a broad aspect of the present invention, there is provided a laminated structure comprising: the laminated object member includes a metal layer on a surface thereof, and a resin film laminated on the surface of the metal layer, wherein the resin film is the resin material.

In a specific aspect of the stacked structure of the present invention, the material of the metal layer is copper.

According to a broad aspect of the present invention, there is provided a multilayer printed wiring board comprising: the circuit board comprises a circuit board, a plurality of insulating layers arranged on the surface of the circuit board, and a metal layer arranged between the insulating layers, wherein at least one insulating layer in the insulating layers is a cured product of the resin material.

Effects of the invention

The resin material of the present invention contains a maleimide compound having a skeleton derived from dimer diamine or a skeleton derived from trimer triamine, and the maleimide compound has a glass transition temperature of 80 ℃ or higher. The resin material of the present invention, having the above-described configuration, (1) can improve uniformity of surface roughness after etching, 2) can improve thermal dimensional stability of a cured product, 3) can improve plating peel strength, 4) can improve embeddability into an uneven surface, and (5) can suppress excessive protrusion from the periphery of a substrate during lamination. The resin material of the present invention can exhibit all of the effects (1) to (5).

Drawings

Fig. 1 is a cross-sectional view schematically showing a multilayer printed wiring board using a resin material according to an embodiment of the present invention.

Detailed Description

The present invention will be described in detail below.

The resin material of the present invention contains a maleimide compound having a skeleton derived from dimer diamine or a skeleton derived from trimer triamine, and the maleimide compound has a glass transition temperature of 80 ℃ or higher.

The resin material of the present invention, having the above-described configuration, (1) can improve uniformity of surface roughness after etching, 2) can improve thermal dimensional stability of a cured product, 3) can improve plating peel strength, 4) can improve embeddability into an uneven surface, and (5) can suppress excessive protrusion from the periphery of a substrate during lamination. The resin material of the present invention can exhibit all of the effects (1) to (5).

In a conventional resin material comprising a maleimide compound and an inorganic filler, a phase separation excessively occurs in a cured product of the resin material, and a component derived from the maleimide compound and the inorganic filler may locally exist, and as a result, the surface roughness of the surface of the cured product after the roughening step may be uneven. Further, in the case where the maleimide compound has a dimer diamine-derived skeleton, the resin material is more easily etched in the roughening step due to the double bond that the dimer diamine-derived skeleton may have. In addition, for example, in a conventional resin material containing a maleimide compound having a skeleton derived from dimer diamine and a glass transition temperature of less than 80 ℃, the skeleton derived from dimer diamine having high etching properties is excessively aggregated, and therefore, the surface roughness after etching may be uneven. In particular, when a maleimide compound having a skeleton derived from dimer diamine and a glass transition temperature of less than 80 ℃ is used in combination with an epoxy compound, the protrusion of the periphery after lamination may be excessively large. In addition, when excessive phase separation occurs in a cured product of a resin material, the compatibility of the maleimide compound with other resin components such as an epoxy compound is reduced, and therefore the fluidity of the inorganic filler is also reduced, and embeddability to the uneven surface may be reduced.

In addition, conventional resin materials containing only a compound having a glass transition temperature of less than 80 ℃ as a resin component may have reduced thermal dimensional stability of a cured product.

On the other hand, since the resin material of the present invention contains a maleimide compound having a specific skeleton and a specific glass transition temperature, the effects of the present invention described in (1) to (5) above can be exhibited.

The resin material of the present invention can reduce surface roughness, and conductor loss due to the skin effect can be reduced in a multilayer substrate such as a multilayer printed wiring board obtained by using a cured product of the resin material.

The resin material of the present invention can reduce the dielectric loss tangent of a cured product at room temperature (e.g., 23 ℃ C.) and at high temperature (e.g., 110 ℃ C.).

The resin material of the present invention may be a resin composition or a resin film. The resin composition has fluidity. The resin composition may be in the form of a paste. The paste comprises a liquid state. The resin material of the present invention is preferably a resin film in view of excellent handling properties.

The resin material of the present invention is preferably a thermosetting resin material. When the resin material is a resin film, the resin film is preferably a thermosetting resin film.

The details of each component used in the resin material of the present invention, the use of the resin material of the present invention, and the like will be described below.

[ Maleimide Compound (Maleimide Compound A) having a skeleton derived from dimer diamine or a skeleton derived from trimer triamine ]

The resin material of the present invention contains a maleimide compound (hereinafter sometimes referred to as "maleimide compound a") having a skeleton derived from dimer diamine or a skeleton derived from trimer triamine. The maleimide compound a may have a skeleton derived from dimer diamine, may have a skeleton derived from trimer triamine, or may have a skeleton derived from dimer diamine and a skeleton derived from trimer triamine. The maleimide compound a may have an aromatic skeleton. The maleimide compound A may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The dimer diamine-derived skeleton and the trimer triamine-derived skeleton are preferably present as partial skeletons in the maleimide compound a.

The maleimide compound a is preferably a bismaleimide compound.

In addition, the maleimide compound includes a citraconimide compound. The citraconimide compound refers to a compound in which a methyl group is bonded to one carbon atom constituting a double bond between carbon atoms in a maleimide group. The maleimide compound a may also be a citraconimide compound. The citraconimide compound has lower reactivity than a maleimide compound, and therefore, the storage stability of the resin material can be improved. The maleimide compound may be a citraconimide compound or a maleimide compound other than the citraconimide compound.

The maleimide compound a preferably has the skeleton derived from dimer diamine or the skeleton derived from trimer triamine at both ends of the main chain. In this case, the maleimide compound a may have the dimer diamine-derived skeleton at both ends of the main chain, the trimer triamine-derived skeleton at both ends of the main chain, or the dimer diamine-derived skeleton at one end of the main chain and the trimer triamine-derived skeleton at the other end of the main chain. In this case, the maleimide compound a may have the dimer diamine-derived skeleton or the trimer triamine-derived skeleton in the skeleton other than the both ends of the main chain and the both ends of the main chain, or may have the dimer diamine-derived skeleton or the trimer triamine-derived skeleton only in the both ends of the main chain. In the case where the maleimide compound a has the dimer diamine-derived skeleton or the trimer triamine-derived skeleton at both ends of the main chain, the reactivity of the maleimide compound a can be improved because a maleimide group is bonded to the dimer diamine skeleton having a high degree of freedom, which is aliphatic. Therefore, the thermal dimensional stability of the cured product can be further improved, and the adhesion between the insulating layer and the metal layer can be further improved.

The compatibility of the maleimide compound A with components other than the maleimide compound A is improved by reducing the content of a dimer diamine-derived skeleton in the main chain skeleton of the maleimide compound A. As a result, the fluidity of the resin material can be improved and the embeddability into the uneven surface can be improved, as compared with the case where the phase separation is strong (for example, the domain size is 1 μm or more).

The maleimide compound a more preferably has the dimer diamine-derived skeleton or the trimer triamine-derived skeleton only at both ends of the main chain. In the case where the maleimide compound a has the dimer diamine-derived skeleton or the trimer triamine-derived skeleton only at both ends of the main chain, the main chain skeleton can be made relatively rigid, and therefore the glass transition temperature of the maleimide compound a can be further effectively increased. Therefore, the thermal dimensional stability of the cured product can be further improved, and the adhesion between the insulating layer and the metal layer can be further improved.

The maleimide compound a preferably has a skeleton derived from a diamine compound other than dimer diamine, and more preferably has both a skeleton derived from dimer diamine and a skeleton derived from a diamine compound other than dimer diamine. In this case, the effects of the present invention (1) to (5) can be effectively exhibited. In addition, when the maleimide compound a has both a skeleton derived from dimer diamine and a skeleton derived from a diamine compound other than dimer diamine, the dielectric loss tangent at high temperatures can be reduced while maintaining thermal dimensional stability. The skeleton derived from the diamine compound other than dimer diamine may be present at both ends of the main chain, or may be present in a portion other than both ends of the main chain.

The maleimide compound a preferably has a skeleton derived from a reactant of a diamine compound other than dimer diamine and acid dianhydride, and more preferably has both a skeleton derived from dimer diamine and a skeleton derived from a reactant of a diamine compound other than dimer diamine and acid dianhydride. In this case, the effects of the present invention (1) to (5) can be effectively exhibited. In addition, when the maleimide compound a has both a skeleton derived from dimer diamine and a skeleton derived from a reactant of a diamine compound other than dimer diamine and acid dianhydride, the dielectric loss tangent at high temperatures can be reduced. The skeleton derived from the reactant of the diamine compound other than dimer diamine and acid dianhydride may be present at both ends of the main chain, or may be present in a portion other than both ends of the main chain.

From the viewpoint of effectively exhibiting the effects of the present invention according to the above (1) to (5), the maleimide compound a preferably has a skeleton derived from a reactant of a diamine compound other than dimer diamine and acid dianhydride at a portion other than both ends of the main chain.

The maleimide compound a is preferably a compound having the skeleton derived from dimer diamine or trimer triamine only at both ends of the main chain and having a skeleton derived from a reactant of a diamine compound other than dimer diamine and acid dianhydride at a portion other than both ends of the main chain. In this case, the effects of the present invention (1) to (5) can be more effectively exhibited, and the dielectric loss tangent at high temperatures can be reduced.

The maleimide compound a can be obtained by reacting an acid dianhydride such as a tetracarboxylic dianhydride with a dimer diamine or a trimer triamine and, if necessary, with a diamine compound other than the dimer diamine or a triamine compound other than the trimer triamine to obtain a reactant, and then reacting the reactant with maleic anhydride.

The maleimide compound a having the dimer diamine-derived skeleton or the trimer triamine-derived skeleton only at both ends of the main chain can be obtained, for example, as follows. The first reactant is obtained by reacting an acid dianhydride such as a tetracarboxylic dianhydride with a diamine compound other than dimer diamine or with a triamine compound other than trimer triamine. The resulting first reactant is reacted with dimer diamine or with trimer triamine to produce a second reactant. Reacting the resulting second reactant with maleic anhydride.

The maleimide compound a having the skeleton derived from dimer diamine or the skeleton derived from trimer triamine and the skeleton derived from a reactant of a diamine compound other than dimer diamine and acid dianhydride at random in a portion other than both ends of the main chain or in a single end of the main chain can be obtained, for example, as follows. An acid dianhydride such as a tetracarboxylic dianhydride is reacted with a diamine compound other than dimer diamine and dimer diamine or trimer triamine to obtain a first reactant having amine skeletons at both ends. The resulting first reactant is reacted with maleic anhydride.

Examples of the tetracarboxylic dianhydride include: pyromellitic dianhydride, 3',4,4' -benzophenonetetracarboxylic dianhydride, 3',4,4' -biphenylsulfonetetracarboxylic dianhydride, 1,4,5, 8-naphthalenetetracarboxylic dianhydride, 2,3,6, 7-naphthalenetetracarboxylic dianhydride, 3',4,4' -biphenylethertetracarboxylic dianhydride, 3',4,4' -dimethyldiphenylsilanetetracarboxylic dianhydride, 3',4,4' -tetraphenylsilanetetracarboxylic dianhydride, 1,2,3, 4-furantetracarboxylic dianhydride, 4,4' -bis (3, 4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 4,4' -bis (3, 4-dicarboxyphenoxy) diphenyl sulfone dianhydride, 4,4' -bis (3, 4-dicarboxyphenoxy) diphenylpropanediol dianhydride, 3,3',4,4' -perfluoroisopropylidene diphthalic dianhydride, 3',4,4' -biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4 '-diphenyl ether dianhydride, and bis (triphenylphthalic acid) -4,4' -diphenylmethane dianhydride, and the like.

Examples of the dimer diamine include: versamine 551 (trade name, manufactured by BASF Japan K.K., 3, 4-bis (1-aminoheptyl) -6-hexyl-5- (1-octenyl) cyclohexene), Versamine552 (trade name, manufactured by Cognis Japan K.K., hydride of Versamine 551), PRIAMINE1075, and PRIAMINE 1074 (trade name, both manufactured by Croda Japan K.K.). Since PRIAMINE 1074 has a larger number of unsaturated bonds than PRIAMINE1075, when PRIAMINE 1074 is used, the desmear property is superior to that when PRIAMINE1075 is used.

Examples of the trimer triamine include PRIAMINE 1071 (trade name, manufactured by Croda Japan K.K.). Since PRIAMINE 1071 has a larger number of unsaturated bonds than PRIAMINE1075, when PRIAMINE 1074 is used, the desmear property is superior to that when PRIAMINE1075 is used. However, PRIAMINE 1071 contains the triamine component in an amount of about 20 to 25% by mass, and therefore, it is necessary to consider the ratio and use it for the reaction.

Examples of the diamine compound other than the dimer diamine include: 1, 3-bis (aminomethyl) cyclohexane, 1, 4-bis (aminomethyl) cyclohexane, bis (aminomethyl) norbornane, 3(4),8(9) -bis (aminomethyl) tricyclo [5.2.1.02,6] decane, 1-bis (4-aminophenyl) cyclohexane, 1, 3-cyclohexanediamine, 1, 4-cyclohexanediamine, 2, 7-diaminofluorene, 4' -ethylenedianiline, isophoronediamine, 4' -methylenebis (cyclohexylamine), 4' -methylenebis (2, 6-diethylaniline), 4' -methylenebis (2-ethyl-6-methylaniline), 4' -methylenebis (2-methylcyclohexylamine), 1, 4-diaminobutane, n-butyl-ethyl-6-methylaniline, n-butyl-ethyl-1, 4-diaminobutane, n-butyl-ethyl-1, 4-methylenebis (2-methylcyclohexylamine), n-butyl-ethyl-4-methyl-2-methyla, 1, 10-diaminodecane, 1, 12-diaminododecane, 1, 7-diaminoheptane, 1, 6-diaminohexane, 1, 5-diaminopentane, 1, 8-diaminooctane, 1, 3-diaminopropane, 1, 11-diaminoundecane, 2-methyl-1, 5-diaminopentane, and the like.

From the viewpoint of effectively exhibiting the effects of the present invention described in (1) to (5), it is preferable that the diamine compound other than the dimer diamine is a diamine compound having 36 or less carbon atoms.

From the viewpoint of effectively exhibiting the effects of the present invention described in (1) to (5), it is preferable that the diamine compound other than the dimer diamine is a diamine compound having a cyclohexane ring skeleton.

Examples of the triamine compound other than the trimer triamine include 1,2, 4-triaminobenzene and the like.

The dimer diamine-derived backbone may or may not have aliphatic rings. The dimer diamine-derived skeleton may or may not have an aliphatic ring.

The skeleton derived from the trimer triamine may or may not have aliphatic rings. The skeleton derived from the trimer triamine may or may not have an alicyclic ring.

The skeleton derived from a diamine compound other than dimer diamine may or may not have an aliphatic ring. The skeleton of the diamine compound derived from other than dimer diamine preferably has an aliphatic ring. Preferably, the aliphatic ring has a cyclohexane ring skeleton.

The skeleton derived from a diamine compound other than dimer diamine may or may not have an aromatic ring. The skeleton derived from a diamine compound other than dimer diamine may or may not have an aromatic ring.

The skeleton derived from the triamine compound may or may not have an aromatic ring. The skeleton derived from the triamine compound may or may not have an aromatic ring.

Examples of the aromatic ring include: benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, tetracene ring,A ring, a benzophenanthrene ring, a benzanthracene ring, a pyrene ring, a pentacene ring, a picene ring, a perylene ring, and the like.

Examples of the alicyclic ring include: a monocycloparaffin ring, a bicycloalkane ring, a tricycloalkane ring, a tetracycloalkane ring, and dicyclopentadiene.

The maleimide compound A has a glass transition temperature of 80 ℃ or higher from the viewpoint of improving the thermal dimensional stability of a cured product and from the viewpoint of improving the adhesion between an insulating layer and a metal layer. When the glass transition temperature of the maleimide compound A is less than 80 ℃, the thermal dimensional stability of the cured product may be lowered.

From the viewpoint of further improving the thermal dimensional stability of the cured product and further improving the adhesion between the insulating layer and the metal layer, the glass transition temperature of the maleimide compound a is preferably 95 ℃ or higher, more preferably 100 ℃ or higher, further preferably 110 ℃ or higher, still further preferably 120 ℃ or higher, and particularly preferably 125 ℃ or higher. The upper limit of the glass transition temperature of the maleimide compound A is not particularly limited. The glass transition temperature of the maleimide compound A may be 190 ℃ or lower, from the viewpoint of ease of synthesis of the maleimide compound.

The glass transition temperature can be determined from the inflection point of the reverse heat flow by heating from-30 ℃ to 200 ℃ at a heating rate of 3 ℃/min under a nitrogen atmosphere using a differential scanning calorimeter ("Q2000" manufactured by TA Instruments).

From the viewpoint of further improving embeddability into the uneven surface, the molecular weight of the maleimide compound a is preferably 1000 or more, more preferably 3000 or more, further preferably 4000 or more, preferably 50000 or less, more preferably 30000 or less, further preferably 20000 or less, and particularly preferably 15000 or less. If the molecular weight of the maleimide compound a is not less than the lower limit, the linear expansion coefficient of the resin material can be suppressed to be low. When the molecular weight of the maleimide compound exceeds 50000, the melt viscosity of the resin material becomes higher and the embeddability to the uneven surface may be reduced, as compared with the case where the molecular weight of the maleimide compound a is 50000 or less.

The molecular weight of the maleimide compound A refers to a molecular weight that can be calculated from the structural formula of the maleimide compound A when the maleimide compound A is a non-polymer compound and the structural formula of the maleimide compound A can be determined. In addition, in the case where the maleimide compound a is a polymer, the molecular weight of the maleimide compound a represents a weight average molecular weight in terms of polystyrene measured by Gel Permeation Chromatography (GPC). Therefore, the weight average molecular weight of the maleimide compound a is preferably in the range satisfying the preferable range.

The weight ratio of the content of the maleimide compound a to the total content of the epoxy compound and the following component X (the content of the maleimide compound a/the total content of the epoxy compound and the component X) is preferably 0.03 or more, more preferably 0.1 or more, further preferably 0.5 or more, and preferably 0.9 or less, more preferably 0.75 or less. When the weight ratio is not less than the lower limit, the dielectric loss tangent at room temperature and at high temperature can be further reduced, the thermal dimensional stability can be further improved, and the desmear property can be improved. When the weight ratio is not more than the upper limit, thermal dimensional stability can be further improved, surface roughness after etching can be further reduced, and plating peel strength can be further improved.

The content of the maleimide compound a in 100 wt% of the components other than the inorganic filler and the solvent in the resin material is preferably 3 wt% or more, more preferably 5 wt% or more, further preferably 10 wt% or more, and preferably 80 wt% or less, more preferably 70 wt% or less, further preferably 50 wt% or less. When the content of the maleimide compound a is not less than the lower limit, the dielectric loss tangent at room temperature and at high temperature can be further reduced, the adhesion between the insulating layer and the metal layer can be further improved, and the desmear property can be improved. When the content of the maleimide compound a is not more than the upper limit, the thermal dimensional stability can be further improved and the surface roughness after etching can be further reduced.

[ epoxy Compound ]

The resin material preferably contains an epoxy compound. As the epoxy compound, a conventionally known epoxy compound can be used. The epoxy compound means an organic compound having at least one epoxy group. The epoxy compounds can be used alone in 1 kind, also can be combined with more than 2 kinds.

As the epoxy compound, there can be mentioned: bisphenol a type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, phenol novolac type epoxy compounds, biphenyl type epoxy compounds, biphenol novolac type epoxy compounds, biphenol type epoxy compounds, naphthalene type epoxy compounds, fluorene type epoxy compounds, phenol aralkyl type epoxy compounds, naphthol aralkyl type epoxy compounds, dicyclopentadiene type epoxy compounds, anthracene type epoxy compounds, epoxy compounds having an adamantane skeleton, epoxy compounds having a tricyclodecane skeleton, naphthyl ether type epoxy compounds, epoxy compounds having a triazine nucleus in the skeleton, and the like.

The epoxy compound preferably contains an epoxy compound having an aromatic skeleton, preferably contains an epoxy compound having a naphthalene skeleton or a phenyl skeleton, and more preferably contains an epoxy compound having an aromatic skeleton, from the viewpoint of further reducing the dielectric loss tangent of the cured product and improving the thermal dimensional stability and flame retardancy of the cured product.

The epoxy compound preferably contains an epoxy compound that is liquid at 25 ℃ and an epoxy compound that is solid at 25 ℃ from the viewpoint of further reducing the dielectric loss tangent of the cured product and improving the coefficient of linear expansion (CTE) of the cured product.

The viscosity of the epoxy compound which is liquid at 25 ℃ is preferably 1000 mPas or less, more preferably 500 mPas or less, at 25 ℃.

For measuring the viscosity of the epoxy compound, for example, a dynamic viscoelasticity measuring apparatus ("VAR-100" manufactured by reorgana Instruments) or the like can be used.

The molecular weight of the epoxy compound is more preferably 1000 or less. In this case, even when the content of the inorganic filler is 50% by weight or more in 100% by weight of the components other than the solvent in the resin material, a resin material having high fluidity at the time of forming the insulating layer can be obtained. Therefore, when an uncured product or a B-staged product of the resin material is laminated on the circuit board, the inorganic filler can be uniformly present.

With respect to the molecular weight of the epoxy compound, in the case where the epoxy compound is a non-polymer compound and the structural formula of the epoxy compound can be determined, the molecular weight of the epoxy compound means a molecular weight that can be calculated from the structural formula. In addition, the weight average molecular weight in the case where the epoxy compound is a polymer.

From the viewpoint of further improving the thermal dimensional stability of the cured product, the content of the epoxy compound is preferably 15% by weight or more, more preferably 25% by weight or more, and preferably 50% by weight or less, more preferably 40% by weight or less, in 100% by weight of the components other than the solvent in the resin material.

The weight ratio of the content of the epoxy compound to the total content of the maleimide compound a and the following component X (content of the epoxy compound/total content of the maleimide compound a and the component X) is preferably 0.2 or more, more preferably 0.3 or more, and preferably 0.9 or less, more preferably 0.8 or less. When the weight ratio is not less than the lower limit and not more than the upper limit, the dielectric loss tangent can be further reduced, and the thermal dimensional stability can be further improved.

[ inorganic Filler ]

The resin material preferably contains an inorganic filler. By using the inorganic filler, the dielectric loss tangent of the cured product can be further reduced. In addition, by using the inorganic filler material, the dimensional change of the cured object due to heat is further reduced. The inorganic filler may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

Examples of the inorganic filler include: silica, talc, clay, mica, hydrotalcite (hydrotalcite), alumina, magnesia, aluminum hydroxide, aluminum nitride, boron nitride, and the like.

The inorganic filler is preferably silicon oxide or aluminum oxide, more preferably silicon oxide, and even more preferably fused silicon oxide, from the viewpoints 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, forming further fine wiring on the surface of the cured product, and imparting more excellent insulation reliability to the cured product. By using silicon oxide, the thermal expansion coefficient of the cured product is further reduced, and the dielectric loss tangent of the cured product is further reduced. Further, by using silicon oxide, the surface roughness of the surface of the cured product is effectively reduced, and the adhesive strength between the cured product and the metal layer is effectively improved. The shape of the silica is preferably spherical.

The inorganic filler is preferably spherical silica from the viewpoint that the curing of the resin proceeds regardless of the curing environment, the glass transition temperature of the cured product is effectively increased, and the thermal linear expansion coefficient of the cured product is effectively reduced.

The average particle diameter of the inorganic filler is preferably 50nm or more, more preferably 100nm or more, further preferably 500nm or more, and preferably 5 μm or less, more preferably 3 μm or less, further preferably 1 μm or less. When the average particle diameter of the inorganic filler is not less than the lower limit and not more than the upper limit, the surface roughness after etching can be reduced, the plating peel strength can be improved, and the adhesion between the insulating layer and the metal layer can be further improved.

As the average particle diameter of the inorganic filler, a value that becomes a median particle diameter (d50) of 50% was used. The average particle diameter can be measured using a particle size distribution measuring apparatus of a laser diffraction scattering system.

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

The inorganic filler is preferably alumina from the viewpoint of improving thermal conductivity and insulating properties.

The inorganic filler is preferably surface-treated, more preferably surface-treated with a coupling agent, and still more preferably surface-treated with a silane coupling agent. By performing surface treatment on the inorganic filler, the surface roughness of the roughened cured product surface is further reduced, and the bonding strength between the cured product and the metal layer is further improved. Further, by surface-treating the inorganic filler, further fine wiring can be formed on the surface of the cured product, and further excellent reliability of insulation between wirings and interlayer insulation can be provided to the cured product.

As the coupling agent, there may be mentioned: silane coupling agents, titanium coupling agents, aluminum coupling agents, and the like. Examples of the silane coupling agent include: methacrylic silane, acrylic silane, aminosilane, imidazolesilane, vinylsilane, epoxysilane, and the like

The content of the inorganic filler is preferably 50% by weight or more, more preferably 60% by weight or more, further preferably 65% by weight or more, particularly preferably 68% by weight or more, and preferably 90% by weight or less, more preferably 85% by weight or less, further preferably 80% by weight or less, particularly preferably 75% by weight or less, of 100% by weight of the components other than the solvent in the resin material. When the content of the inorganic filler is not less than the lower limit, the dielectric loss tangent is effectively reduced. When the content of the inorganic filler is not more than the upper limit, thermal dimensional stability can be improved and warpage of a cured product can be effectively suppressed. When the content of the inorganic filler is not less than the lower limit and not more than the upper limit, the surface roughness of the surface of the cured product can be further reduced, and further fine wiring can be formed on the surface of the cured product. The content of the inorganic filler can reduce the thermal expansion coefficient of the cured product and improve the desmear property.

[ Maleimide Compound having no skeleton derived from dimer diamine, or Maleimide Compound (Maleimide Compound B) having a skeleton derived from dimer diamine and a molecular weight of 1000 or less ]

The resin material preferably contains a maleimide compound having no skeleton derived from dimer diamine, or a maleimide compound having a skeleton derived from dimer diamine and having a molecular weight of 1000 or less (hereinafter sometimes referred to as "maleimide compound B"). The maleimide compound B may be a maleimide compound having no skeleton derived from dimer diamine, or a maleimide compound having a skeleton derived from dimer diamine and having a molecular weight of 1000 or less. The maleimide compound B may be both a maleimide compound having no skeleton derived from dimer diamine and a maleimide compound having a skeleton derived from dimer diamine and having a molecular weight of 1000 or less. The maleimide compound B is different from the maleimide compound a. The effect of the present invention can be more effectively exhibited by using the maleimide compound a in combination with the maleimide compound B. The maleimide compound B preferably has no skeleton derived from a trimer triamine. The maleimide compound B preferably has a skeleton derived from a diamine compound other than dimer diamine, but may not have a skeleton derived from a diamine compound. The maleimide compound B preferably has an aromatic skeleton. The maleimide compound B may have a glass transition temperature of less than 80 ℃. The maleimide compound B may be a polymaleimide compound having 3 or more maleimide skeletons. The maleimide compound B may be a citraconimide compound. The maleimide compound B may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

In the maleimide compound B, it is preferable that a nitrogen atom in the maleimide skeleton is bonded to an aromatic ring.

Examples of the maleimide compound B include an N-phenylmaleimide compound and the like.

From the viewpoint of effectively exerting the effects of the above (1) to (5), the maleimide compound B preferably contains an N-phenylmaleimide compound, more preferably an N-phenylmaleimide compound.

The content of the maleimide compound B in 100 wt% of the components other than the inorganic filler and the solvent in the resin material is preferably 2.5 wt% or more, more preferably 5 wt% or more, further preferably 7.5 wt% or more, and preferably 50 wt% or less, more preferably 35 wt% or less. When the content of the maleimide compound B is not less than the lower limit and not more than the upper limit, the effects of the present invention (1) to (5) can be further exhibited, and particularly, the thermal dimensional stability of the cured product can be further improved.

From the viewpoint of effectively exerting the effects of the present invention described in (1) to (5), the molecular weight of the maleimide compound B is preferably 100 or more, more preferably 1000 or more, and is preferably less than 30000, more preferably less than 20000.

Regarding the molecular weight of the maleimide compound B, in the case where the maleimide compound B is a non-polymer compound and the structural formula of the maleimide compound B can be determined, the molecular weight of the maleimide compound B means a molecular weight that can be calculated from the structural formula. In addition, in the case where the maleimide compound B is a polymer, the molecular weight of the maleimide compound B represents a weight average molecular weight in terms of polystyrene measured by Gel Permeation Chromatography (GPC).

Examples of the commercially available product of the maleimide compound (maleimide compound B) having no skeleton derived from dimer diamine include: "MIR-3000" manufactured by Nippon Kabushiki Kaisha, "BMI 4000" and "BMI 5100" manufactured by Daihe Kabushiki Kaisha. Examples of commercially available maleimide compounds (maleimide compounds B) having a dimer diamine-derived skeleton and a molecular weight of 1000 or less include "BMI-689" manufactured by Designer Molecules inc. Further, as a commercially available product of the maleimide compound (maleimide compound B) as the citraconimide compound, for example, "BCI-737" manufactured by Designer polymers inc.

[ curing agent ]

The resin material preferably contains a curing agent. The curing agent is not particularly limited. As the curing agent, a conventionally known curing agent can be used. The curing agent can be used alone in 1 kind, also can be combined with the use of 2 or more.

Examples of the curing agent include: cyanate ester compounds (cyanate curing agent), amine compounds (amine curing agent), thiol compounds (thiol curing agent), imidazole compounds, phosphine compounds, dicyandiamide, phenol compounds (phenol curing agent), acid anhydrides, active ester compounds, carbodiimide compounds (carbodiimide curing agent), and benzoxazine compounds (benzoxazine curing agent). The curing agent preferably has a functional group capable of reacting with an epoxy group of the epoxy compound.

From the viewpoint of further improving the thermal dimensional stability, the curing agent preferably contains at least 1 component selected from the group consisting of phenol compounds, cyanate ester compounds, acid anhydrides, active ester compounds, carbodiimide compounds, and benzoxazine compounds. That is, the resin material is preferably a curing agent containing at least 1 component selected from the group consisting of a phenol compound, a cyanate ester compound, an acid anhydride, an active ester compound, a carbodiimide compound, and a benzoxazine compound.

In the present specification, "at least 1 component out of the phenol compound, the cyanate ester compound, the acid anhydride, the active ester compound, the carbodiimide compound, and the benzoxazine compound" may be referred to as "component X".

The benzoxazine compound is preferably a benzoxazine compound having a skeleton derived from a dimer diamine, from the viewpoint of effectively exhibiting the effects of the present invention according to (1) to (5) and from the viewpoint of improving the desmear property.

Therefore, the resin material preferably contains a curing agent containing the component X. The component X may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

As the phenol compound, there may be mentioned: novolak-type phenols, biphenol-type phenols, naphthalene-type phenols, dicyclopentadiene-type phenols, aralkyl-type phenols, dicyclopentadiene-type phenols, and the like.

As the commercial products of the phenol compounds, there can be mentioned: novolak-type phenols ("TD-2091" manufactured by DIC K.K.), diphenolnovolak-type phenols ("MEH-7851" manufactured by Minghuazai Kabushiki Kaisha), aralkyl-type phenol compounds ("MEH-7800" manufactured by Minghuazakiki Kabushiki Kaisha), phenols having an aminotriazine skeleton ("LA 1356" and "LA 3018-50P" manufactured by DIC K.K.), and the like.

Examples of the cyanate ester compound include a novolak type cyanate ester resin, a bisphenol type cyanate ester resin, and a prepolymer obtained by trimerizing a part of these resins. Examples of the novolac-type cyanate ester resin include phenol novolac-type cyanate ester resins and alkylphenol-type cyanate ester resins. Examples of the bisphenol type cyanate ester resin include bisphenol a type cyanate ester resin, bisphenol E type cyanate ester resin, and tetramethyl bisphenol F type cyanate ester resin.

Examples of commercially available products of the cyanate ester compound include: phenol novolak-type cyanate ester resins ("PT-30" and "PT-60" manufactured by Lonza Japan K.K.), and prepolymers obtained by trimerizing bisphenol-type cyanate ester resins ("BA-230S", "BA-3000S", "BTP-1000S" and "BTP-6020S" manufactured by Lonza Japan K.K.), and the like.

Examples of the acid anhydride include tetrahydrophthalic anhydride and an alkylstyrene-maleic anhydride copolymer.

As the commercially available product of the acid anhydride, RIKACID TDA-100 manufactured by Nissian chemical Co., Ltd.

The active ester compound refers to a compound having at least one ester bond in the structure, and an aliphatic chain, an aliphatic ring, or an aromatic ring is bonded to both sides of the ester bond. The active ester compound can be obtained, for example, by condensation reaction of a carboxylic acid compound or a thiocarboxylic acid compound with a hydroxyl compound or a thiol compound. Examples of the active ester compound include compounds represented by the following formula (1).

[ chemical formula 1]

In the formula ((1), X1 represents an aliphatic chain-containing group, an aliphatic ring-containing group or an aromatic ring-containing group, and X2 represents an aromatic ring-containing group preferred examples of the aromatic ring-containing group include a benzene ring which may have a substituent, a naphthalene ring which may have a substituent, and the like, and the substituent includes a hydrocarbon group having preferably 12 or less, more preferably 6 or less, and further preferably 4 or less carbon atoms.

Examples of the combination of X1 and X2 include: a combination of a benzene ring which may have a substituent and a benzene ring which may have a substituent, a combination of a benzene ring which may have a substituent and a naphthalene ring which may have a substituent. Further, as the combination of X1 and X2, a combination of a naphthalene ring which may have a substituent and a naphthalene ring which may have a substituent is exemplified.

The active ester compound is not particularly limited. The active ester is preferably an active ester compound having 2 or more aromatic skeletons from the viewpoint of improving thermal dimensional stability and flame retardancy. From the viewpoint of reducing the dielectric loss tangent of a cured product and improving the thermal dimensional stability of a cured product, it is preferable that the active ester has a naphthalene ring in the main chain skeleton.

Commercially available products of the active ester compound include "HPC-8000-65T", "EXB-9416-70 BK", "EXB-8100-65T", "EXB-8", "HPC-8150-62T", and "HPC-8150-60T", manufactured by DIC corporation.

The carbodiimide compound has a structural unit represented by the following formula (2). In the following formula (2), the right and left end portions are bonding sites to other groups. The carbodiimide compound may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

[ chemical formula 2]

In the formula (2), X represents an alkylene group, a group having a substituent bonded to the alkylene group, a cycloalkylene group, a group having a substituent bonded to the cycloalkylene group, an arylene group, or a group having a substituent bonded to the arylene group, and p represents an integer of 1 to 5. When there are a plurality of xs, the plurality of xs may be the same or different.

In a preferred embodiment, at least one X is an alkylene group, a group having a substituent bonded to an alkylene group, a cycloalkylene group, or a group having a substituent bonded to a cycloalkylene group.

Commercially available products of the carbodiimide compound include: "Carbodilite V-02B", "Carbodilite V-03", "Carbodilite V-04K", "Carbodilite V-07", "Carbodilite V-09", "Carbodilite 10M-SP", and "Carbodilite 10M-SP (modified)", manufactured by Nisshinbo Chemical Co., Ltd., and "Stabaxol P", "Stabaxol P400", and "Hycasyl 510", manufactured by Rhein Chemie K.K., and the like.

Examples of the benzoxazine compound include P-d type benzoxazine, F-a type benzoxazine, and the like.

Examples of commercially available products of the benzoxazine compound include "P-d type" manufactured by Shikoku Kabushiki Kaisha.

The content of the component X is preferably 70 parts by weight or more, more preferably 85 parts by weight or more, and preferably 150 parts by weight or less, more preferably 120 parts by weight or less, relative to 100 parts by weight of the epoxy compound. When the content of the component X is not less than the lower limit and not more than the upper limit, curability is further excellent, thermal dimensional stability is further improved, and volatilization of the remaining unreacted component can be further suppressed.

The total content of the epoxy compound and the component X is preferably 50% by weight or more, more preferably 60% by weight or more, and preferably 90% by weight or less, more preferably 85% by weight or less, in 100% by weight of the components other than the inorganic filler and the solvent in the resin material. When the total content of the epoxy compound and the component X is not less than the lower limit and not more than the upper limit, curability is further excellent and thermal dimensional stability can be further improved.

[ curing accelerators ]

The resin material preferably contains a curing accelerator. By using the curing accelerator, the curing speed becomes even faster. By rapidly curing the resin material, the crosslinked structure in the cured product becomes uniform, and the number of unreacted functional groups decreases, resulting in an increase in the crosslinking density. The curing accelerator is not particularly limited, and conventionally known curing accelerators can be used. The curing accelerator may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

Examples of the curing accelerator include: an anionic curing accelerator such as an imidazole compound, a cationic curing accelerator such as an amine compound, a curing accelerator other than anionic and cationic curing accelerators such as a phosphorus compound and an organic metal compound, and a radical curing accelerator such as a peroxide.

As the imidazole compound, there may be mentioned: 2-undecylimidazole, 2-heptadecylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1, 2-dimethylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2-ethylguanidinium trimellitate, 2-phenylimidazolium trimellit, 2, 4-diamino-6- [2' -methylimidazolyl- (1') ] -ethyl-s-triazine, 2, 4-diamino-6- [2' -undecylimidazolyl- (1') ] -ethyl-s-triazine, 2, 4-diamino-6- [2' -ethyl-4 ' -methylimidazolyl- (1') ] -ethyl-s-triazine, 2, 4-diamino-6- [2' -methylimidazolyl- (1') ] -ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenyl-4, 5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-dihydroxymethylimidazole, and the like.

As the amine compound, there may be mentioned: diethylamine, triethylamine, diethylenetetramine, triethylenetetramine, 4-dimethylaminopyridine, and the like.

Examples of the phosphorus compound include a triphenylphosphine compound and the like.

As the organometallic compound, there can be mentioned: zinc naphthenate, cobalt naphthenate, tin octylate, cobalt (II) bisacetylpyruvate, cobalt (III) triacetylapyruvate, and the like.

Examples of the peroxide include dicumyl peroxide and Perhexa 25B.

When the peroxide is used as the curing accelerator, a 1-minute half-life temperature can be set between the pre-curing temperature and the final curing temperature, and therefore, the surface roughness can be improved, and the plating peel strength and desmear property can be further improved.

From the viewpoint of suppressing the curing temperature to be lower and effectively suppressing the warpage of the cured product, the curing accelerator preferably contains the anionic curing accelerator, and more preferably contains the imidazole compound.

From the viewpoint of suppressing the curing temperature to a lower level and effectively suppressing the warpage of the cured product, the content of the anionic curing accelerator in 100 wt% of the curing accelerator is preferably 20 wt% or more, more preferably 50 wt% or more, still more preferably 70 wt% or more, and most preferably 100 wt% (total amount). Therefore, the curing accelerator is most preferably the anionic curing accelerator.

The content of the curing accelerator is not particularly limited. The content of the curing accelerator is preferably 0.01 wt% or more, more preferably 0.05 wt% or more, and preferably 5 wt% or less, more preferably 3 wt% or less, of 100 wt% of the components other than the inorganic filler and the solvent in the resin material. When the content of the curing accelerator is not less than the lower limit and not more than the upper limit, the resin material is efficiently cured. When the content of the curing accelerator is in a more preferable range, the storage stability of the resin material is further improved, and a further excellent cured product can be obtained.

[ thermoplastic resin ]

The resin material preferably contains a thermoplastic resin. Examples of the thermoplastic resin include polyvinyl acetal resin, polyimide resin, and phenoxy resin. The thermoplastic resin can be used alone in 1, also can be combined with more than 2.

The thermoplastic resin is preferably a phenoxy resin from the viewpoint of effectively reducing the dielectric loss tangent regardless of the curing environment and effectively improving the adhesion of the metal wiring. By using the phenoxy resin, deterioration of embeddability of the resin film into holes or irregularities of the circuit board and non-uniformity of the inorganic filler are suppressed. In addition, since the use of the phenoxy resin enables adjustment of the melt viscosity, the dispersibility of the inorganic filler becomes good, and the resin composition or the B-staged material is less likely to be wetted and spread to unintended areas during the curing process.

The phenoxy resin contained in the resin material is not particularly limited. As the phenoxy resin, conventionally known phenoxy resins can be used. The phenoxy resin can be used alone in 1 kind, also can be combined with more than 2 kinds.

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

Examples of commercially available products of the phenoxy resin include "YP 50", "YP 55" and "YP 70" manufactured by neisseria chemical corporation, and "1256B 40", "4250", "4256H 40", "4275", "YX 6954BH 30" and "YX 8100BH 30" manufactured by mitsubishi chemical corporation.

The thermoplastic resin is preferably a polyimide resin (polyimide compound) from the viewpoint of improving workability, plating peel strength at low roughness, and adhesion between the insulating layer and the metal layer.

The polyimide compound is preferably a polyimide compound obtained by a method of reacting tetracarboxylic dianhydride with dimer diamine, from the viewpoint of satisfactory solubility.

Examples of the tetracarboxylic dianhydride include: pyromellitic dianhydride, 3',4,4' -benzophenonetetracarboxylic dianhydride, 3',4,4' -biphenylsulfonetetracarboxylic dianhydride, 1,4,5, 8-naphthalenetetracarboxylic dianhydride, 2,3,6, 7-naphthalenetetracarboxylic dianhydride, 3',4,4' -biphenylethertetracarboxylic dianhydride, 3',4,4' -dimethyldiphenylsilanetetracarboxylic dianhydride, 3',4,4' -tetraphenylsilanetetracarboxylic dianhydride, 1,2,3, 4-furantetracarboxylic dianhydride, 4,4' -bis (3, 4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 4,4' -bis (3, 4-dicarboxyphenoxy) diphenyl sulfone dianhydride, 4,4' -bis (3, 4-dicarboxyphenoxy) diphenyl propane dianhydride, 3,3',4,4' -perfluoroisopropylidenedicarboxylic dianhydride, 3',4,4' -biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4 '-diphenylether dianhydride, bis (triphenylphthalic acid) -4,4' -diphenylmethane dianhydride, and the like.

Examples of the dimer diamine include: versamine 551 (trade name: BASF Japan K.K., 3, 4-bis (1-aminoheptyl) -6-hexyl-5- (1-octenyl) cyclohexene), Versamine552 (trade name: Cognis Japan K.K., hydride of Versamine 551), PRIAMINE1075, PRIAMINE 1074 (trade name: all of Croda Japan K.K.), and the like.

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

From the viewpoint of obtaining a resin material having still more excellent storage stability, the weight average molecular weight of the thermoplastic resin, the polyimide resin, and the phenoxy resin is preferably 5000 or more, more preferably 10000 or more, and is preferably 100000 or less, more preferably 50000 or less.

The weight average molecular weight of the thermoplastic resin, the polyimide resin, and the phenoxy resin represents a weight average molecular weight in terms of polystyrene measured by Gel Permeation Chromatography (GPC).

The contents of the thermoplastic resin, the polyimide resin and the phenoxy resin are not particularly limited. The content of the thermoplastic resin (in the case where the thermoplastic resin is a polyimide resin or a phenoxy resin, the content of the polyimide resin or the phenoxy resin) is preferably 1 wt% or more, more preferably 2 wt% or more, and preferably 30 wt% or less, more preferably 20 wt% or less, in 100 wt% of the components other than the inorganic filler and the solvent in the resin material. If the content of the thermoplastic resin is not less than the lower limit and not more than the upper limit, the resin material can be favorably embedded in the hole or the unevenness of the circuit board. When the content of the thermoplastic resin is not less than the lower limit, a resin film can be further easily formed, and a further excellent insulating layer can be obtained. When the content of the thermoplastic resin is not more than the upper limit, the thermal expansion coefficient of the cured product is further decreased. When the content of the thermoplastic resin is not more than the upper limit, the surface roughness of the surface of the cured product is further reduced, and the adhesive strength between the cured product and the metal layer is further improved.

[ solvent ]

The resin material may or may not contain a solvent. By using the solvent, the viscosity of the resin material can be controlled to an appropriate range, and the coatability of the resin material can be improved. In addition, the solvent may be used to obtain a slurry containing the inorganic filler material. The solvent can be used alone in 1, also can be combined with more than 2.

As the solvent, there may be mentioned: acetone, methanol, ethanol, butanol, 2-propanol, 2-methoxyethanol, 2-ethoxyethanol, 1-methoxy-2-propanol, 2-acetoxy-1-methoxypropane, toluene, xylene, methyl ethyl ketone, N-dimethylformamide, methyl isobutyl ketone, N-methylpyrrolidone, N-hexane, cyclohexane, cyclohexanone, and naphtha as a mixture.

The solvent is preferably removed in many cases when the resin composition is formed into a film. Therefore, the boiling point of the solvent is preferably 200 ℃ or less, more preferably 180 ℃ or less. The content of the solvent in the resin composition is not particularly limited. The content of the solvent may be appropriately changed in consideration of coatability of the resin composition and the like.

In the case where the resin material is a B-staged film, the content of the solvent is preferably 1 wt% or more, more preferably 2 wt% or more, and preferably 10 wt% or less, more preferably 5 wt% or less, in 100 wt% of the B-staged film.

[ other ingredients ]

The resin material may contain a leveling agent, a flame retardant, a coupling agent, a colorant, an antioxidant, an ultraviolet degradation inhibitor, a defoaming agent, a thickener, a thixotropy-imparting agent, and a thermosetting resin other than an epoxy compound, for the purpose of improving impact resistance, heat resistance, compatibility of the resin, workability, and the like.

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

Examples of the other thermosetting resin include: polyphenylene ether resins, divinyl benzyl ether resins, polyarylate resins, diallyl phthalate resins, benzoxazole resins, acrylate resins, and the like.

(resin film)

By forming the resin composition into a film shape, a resin film (B-staged material/B-staged film) can be obtained. The resin material is preferably a resin film. The resin film is preferably a B-stage film.

As a method for obtaining a resin film by molding the resin composition into a film shape, the following method can be mentioned. The extrusion molding method is a method in which the resin composition is melt kneaded using an extruder, extruded, and then molded into a film shape by a T-die, a circular die, or the like. A casting method in which a resin composition containing a solvent is cast into a film shape. Other film forming methods are known. Extrusion molding or casting molding is preferable because it can cope with the reduction in thickness. The membrane comprises a sheet.

The resin composition is formed into a film shape, and is dried by heating at 50 to 150 ℃ for 1 to 10 minutes, for example, to such an extent that curing by heat does not proceed excessively, whereby a resin film as a B-stage film can be obtained.

The film-like resin composition obtainable by the drying step as described above is referred to as a B-stage film. The B-stage film is in a semi-cured state. The semi-cured product is not completely cured, and curing may be further performed.

The resin film may be a non-prepreg. In the case where the resin film is a non-prepreg, migration (migration) along a glass cloth or the like does not occur. Further, when the resin film is laminated or precured, unevenness due to the glass cloth does not occur on the surface. The resin film may be used in the form of a laminate film including a metal foil or a substrate and a resin film laminated on the surface of the metal foil or the substrate. The metal foil is preferably a copper foil.

As the substrate of the laminated film, there may be mentioned: polyester resin films such as polyethylene terephthalate films and polybutylene terephthalate films, olefin resin films such as polyethylene films and polypropylene films, and polyimide resin films. The surface of the substrate may be subjected to a release treatment as required.

From the viewpoint of further uniformly controlling the degree of curing of the resin film, the thickness of the resin film is preferably 5 μm or more, and preferably 200 μm or less. When the resin film is used as an insulating layer of a circuit, the thickness of the insulating layer formed of the resin film is preferably equal to or greater than the thickness of a conductor layer (metal layer) forming the circuit. The thickness of the insulating layer is preferably 5 μm or more, and preferably 200 μm or less.

(semiconductor device, printed Wiring Board, copper-clad laminate, and multilayer printed Wiring Board)

The resin material can be suitably used for forming a mold resin embedding a semiconductor chip in a semiconductor device.

The resin material can be suitably used for forming an insulating layer in a printed wiring board.

The printed wiring board can be obtained by, for example, heating and pressing the resin material.

The resin film is laminated on one or both surfaces thereof with a member to be laminated having a metal layer on the surface thereof. Preferably, a laminated structure is obtained which comprises a member to be laminated having a metal layer on a surface thereof and a resin film laminated on the surface of the metal layer, wherein the resin film is the resin material. The method for laminating the resin film and the member to be laminated having the metal layer on the surface is not particularly limited, and a known method can be used. For example, the resin film can be laminated on a member to be laminated having a metal layer on the surface thereof by heating and pressing or by pressing without heating using a device such as a parallel plate press or a roll laminator.

The material of the metal layer is preferably copper.

The member to be laminated having a metal layer on the surface may be a metal foil such as a copper foil.

The resin material can be suitably used for obtaining a copper-clad laminate. As an example of the copper-clad laminate, there is a copper-clad laminate including a copper foil and a resin film laminated on one surface of the copper foil.

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. In order to improve the adhesion strength between the cured product of the resin material and the copper foil, the copper foil preferably has fine irregularities on the surface. The method for forming the unevenness is not particularly limited. Examples of the method for forming the irregularities include a known method for forming by a treatment using a chemical solution.

The resin material can be suitably used to obtain a multilayer substrate.

As an example of the multilayer substrate, there is a multilayer substrate including a circuit board and an insulating layer laminated on the circuit board. The insulating layer of the multilayer substrate is formed by the resin material. In addition, the insulating layer of the multilayer substrate may be formed using a laminate film and the resin film of the laminate film. The insulating layer is preferably laminated on the surface of the circuit substrate on which the circuit is provided. A portion of the insulating layer is preferably embedded between the circuits.

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

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

In addition, the multilayer substrate preferably further includes a copper plating layer laminated on the roughened surface of the insulating layer.

In addition, another example of the multilayer substrate includes a circuit board, an insulating layer laminated on a surface of the circuit board, and a copper foil laminated on a surface of the insulating layer opposite to the surface on which the circuit board is laminated. Preferably, the insulating layer is formed by curing a copper-clad laminate including a copper foil and a resin film laminated on one surface of the copper foil. The copper foil is preferably etched and used as a copper circuit.

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

A multilayer printed wiring board in a multilayer substrate is required to have a low dielectric loss tangent and high insulation reliability by an insulating layer. Therefore, the resin material of the present invention can be suitably used for forming an insulating layer in a multilayer printed wiring board.

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

Fig. 1 is a cross-sectional view schematically showing a multilayer printed wiring board using a resin material according to an embodiment of the present invention.

In the multilayer printed wiring board 11 shown in fig. 1, a plurality of insulating layers 13 to 16 are laminated on an upper surface 12a of a circuit board 12. The insulating layers 13 to 16 are cured layers. A metal layer 17 is formed on a partial region of the upper surface 12a of the circuit board 12. In the multilayer insulating layers 13 to 16, a metal layer 17 is formed in a partial region of the upper surfaces of the insulating layers 13 to 15 excluding the insulating layer 16 located on the outer surface opposite to the circuit board 12 side. The metal layer 17 is a circuit. A metal layer 17 is disposed between the circuit board 12 and the insulating layer 13 and between the stacked insulating layers 13 to 16. The lower metal layer 17 and the upper metal layer 17 are connected to each other by at least one of a via connection and a via connection, not shown.

In the multilayer printed wiring board 11, the insulating layers 13 to 16 are formed by a cured product of the resin material. In the present embodiment, the surfaces of the insulating layers 13 to 16 are roughened, so that fine holes, not shown, are formed in the surfaces of the insulating layers 13 to 16. The metal layer 17 reaches the inside of the fine pores. In the multilayer printed wiring board 11, the width direction dimension (L) of the metal layer 17 and the width direction dimension (S) of the portion where the metal layer 17 is not formed can be reduced. In addition, in the multilayer printed wiring board 11, good insulation reliability is provided between the upper metal layer and the lower metal layer to which via connection and via connection, not shown, are not connected.

(roughening treatment and swelling treatment)

The resin material is preferably used to obtain a cured product to be subjected to roughening treatment or desmear treatment. The cured product includes a pre-cured product that can be further cured.

In order to form fine irregularities on the surface of a cured product obtained by precuring the resin material, it is preferable to subject the cured product to roughening treatment. Before the roughening treatment, the cured product is preferably subjected to swelling treatment. The cured product is preferably subjected to swelling treatment after the precuring and before the roughening treatment, and is cured after the roughening treatment. However, the cured product is not necessarily subjected to swelling treatment.

As the swelling treatment method, for example, a method of treating a cured product with an aqueous solution or an organic solvent dispersion solution of a compound containing ethylene glycol or the like as a main component can be used. The swelling liquid used for the swelling treatment usually contains an alkali as a pH adjuster or the like. The swelling liquid preferably contains sodium hydroxide. Specifically, for example, the swelling treatment is performed by treating the cured product at a treatment temperature of 30 to 85 ℃ for 1 to 30 minutes using a 40 wt% ethylene glycol aqueous solution or the like. The temperature of the swelling treatment is preferably in the range of 50 to 85 ℃. If the temperature of the swelling treatment is too low, the swelling treatment takes a long time, and the bonding strength between the cured product and the metal layer tends to decrease.

For the roughening treatment, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfate compound is used. The chemical oxidizing agent is used in the form of an aqueous solution or an organic solvent dispersion solution after adding water or an organic solvent. The roughening solution used for the roughening treatment usually contains an alkali as a pH adjuster or the like. The roughening liquid 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 arithmetic average roughness Ra of the surface of the cured product is preferably 10nm or more, and is preferably less than 300nm, more preferably less than 200nm, and still more preferably less than 150 nm. In this case, the adhesive strength between the cured product and the metal layer is improved, and further fine wiring is formed on the surface of the insulating layer. Further, the conductor loss can be suppressed, and the signal loss can be suppressed to be low. The arithmetic average roughness Ra is measured in accordance with JIS B0601: 1994, to perform the assay.

(treatment of desmearing)

A through hole may be formed in a cured product obtained by precuring the resin material. In the multilayer substrate and the like, via holes, through holes, and the like are formed as through holes. For example, the via hole can be irradiated with CO₂Laser light such as laser light. The diameter of the via hole is not particularly limited, and is about 60 μm to 80 μm. By forming the through hole, a residue of the resin, which is a resin component contained in the cured product, is often formed at the bottom of the through hole.

In order to remove the smear, it is preferable to perform desmear treatment on the surface of the cured product. The desmear treatment may be performed as the roughening treatment.

In the desmear treatment, for example, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfate compound can be used in the same manner as in the roughening treatment. These chemical oxidizing agents are used in the form of an aqueous solution or an organic solvent dispersion solution after adding water or an organic solvent. The desmear treatment solution used for desmear treatment usually contains an alkali. The desmear treatment solution preferably contains sodium hydroxide.

By using the resin material, the surface roughness of the surface of the cured product subjected to desmear treatment is sufficiently reduced.

The present invention will be specifically described below with reference to examples and comparative examples. The present invention is not limited to the following examples.

The following materials were prepared.

(Maleimide Compound)

< Maleimide A >)

Maleimide compound A1 (molecular weight 9000) synthesized according to Synthesis example 1 described below

Maleimide compound A2 (molecular weight 4500) synthesized according to synthetic example 2 described below

< Maleimide Compound B >

N-alkylbismaleimide Compound 1 ("BMI-3000" manufactured by Designer Molecules Inc., molecular weight exceeding 3000)

N-alkylbismaleimide Compound 2 ("BMI-689" manufactured by Designer Molecules Inc., molecular weight less than 1000)

N-phenylmaleimide compound ("MIR-3000" manufactured by Nippon Kagaku K.K., molecular weight of less than 1000)

(Synthesis example 1)

55g of pyromellitic dianhydride (molecular weight 254.15, manufactured by Tokyo chemical Co., Ltd.) and 300g of toluene were added to a reaction vessel equipped with a stirrer, a water separator, a thermometer, and a nitrogen gas inlet tube, and the solution in the reaction vessel was heated to 60 ℃. Then, 26.7g of bis (aminomethyl) norbornane (molecular weight: 154.26, manufactured by Tokyo chemical industries, Ltd.) was dissolved in toluene to obtain a reaction product having acid anhydrides at both ends, which was added dropwise to the reaction vessel. Then, 46.0g of dimer diamine ("PRIAMINE 1075" manufactured by Croda Japan K.K.) was slowly added to the reaction vessel, a dean-Stark separator and a condenser were attached to the flask, and the mixture was heated under reflux for 2 hours to obtain an imide compound having an amine structure at both ends. Next, 8.7g of maleic anhydride was added, and the resulting mixture was refluxed for 12 hours to perform maleimide-addition. Subsequently, isopropyl alcohol was injected to precipitate the product, which was then recovered, and the product was dried in a vacuum oven, thereby obtaining a maleimide compound a1 having a dimer diamine-derived skeleton only at both ends of the main chain. The yield of the maleimide compound A1 was 83%.

(Synthesis example 2)

250mL of toluene was placed in a 500mL round bottom flask, and 13.2g (32mmol) of dimer diamine ("PRIAMINE 1075" manufactured by Croda Japan K.K.) and 24.9g (128mmol) of tricyclodecanediamine were added thereto. Next, 35.3g (120mmol) of biphenylic acid dianhydride was added stepwise in small amounts. The eggplant-shaped flask was set in a dean-stark apparatus, and heated under reflux for 2 hours. This gives a compound having an amine at both ends and having a plurality of imide skeletons. After the water discharged during the condensation was removed and the reaction mixture was returned to room temperature, 8.83g (90mmol) of maleic anhydride was added thereto, followed by stirring and heating in the same manner to effect a reaction. This gives a compound having maleimide skeletons at both ends. The resultant was reprecipitated by adding isopropyl alcohol. Thereafter, drying was performed by a vacuum oven, to obtain a maleimide compound a2 having a skeleton derived from dimer diamine. The maleimide compound a2 has the following formula (a 2).

[ chemical formula 3]

The molecular weights of the maleimide compounds a1 and a2 synthesized in synthesis examples 1 and 2 were determined in the following manner.

GPC (gel permeation chromatography) assay:

the measurement was performed using a high performance liquid chromatography system manufactured by Shimadzu corporation using Tetrahydrofuran (THF) as a developing solvent under conditions of a column temperature of 40 ℃ and a flow rate of 1.0 ml/min. "SPD-10A" was used as a detector, and 2 columns were used by connecting "KF-804L" (excluding the limiting molecular weight of 400000) manufactured by Shodex Co., Ltd in series. As the Standard Polystyrene, "TSK Standard Polystyrene" manufactured by tokyo corporation was used, and calibration curves were prepared using materials having weight average molecular weights Mw of 354000, 189000, 98900, 37200, 17100, 9830, 5870, 2500, 1050, and 500, and the molecular weights were calculated.

(epoxy compound)

Biphenyl epoxy Compound (NC-3000 manufactured by Nippon Kabushiki Kaisha)

Resorcinol diglycidyl ether ("EX-201" manufactured by Nagase chemteX Co.)

Multi-branched aliphatic epoxy Compound ("FoldiE 101" manufactured by Nissan chemical Co., Ltd.)

Naphthalene type epoxy Compound (HP-4032D, manufactured by DIC corporation)

Naphthol aralkyl type epoxy Compound ("ESN-475V" manufactured by Nippon iron Japan chemical Co., Ltd.)

(inorganic Filler)

Silica-containing slurry (silica 75 wt%; manufactured by Admatechs corporation "SC 4050-HOA", average particle diameter 1.0 μm, aminosilane-treated, cyclohexanone 25 wt%)

(curing agent)

Component X:

cyanate ester Compound-containing liquid ("BA-3000S" manufactured by Lonza Japan K.K., solid content: 75 wt%)

Active ester Compound 1-containing liquid ("EXB-9416-70 BK" manufactured by DIC corporation, solid content 70 wt%)

Active ester Compound 2 ("EXB-8" manufactured by DIC corporation, solid content: 100% by weight)

Active ester Compound 3-containing solution ("HPC-8150-62T" manufactured by DIC corporation, solid content 62 wt%)

Phenol compound-containing solution ("LA-1356" manufactured by DIC corporation, solid content 60 wt%)

Carbodiimide Compound-containing liquid ("V-03" manufactured by Nisshinbo Chemical Co., Ltd., "solid content: 50% by weight)

Benzoxazine compound synthesized according to synthesis example 3 (benzoxazine compound having a skeleton derived from dimer diamine)

(Synthesis example 3)

100mL of toluene was added to a 250mL reaction vessel, and 10.25g (25mmol) of dimer diamine ("PRIAMINE 1075" manufactured by Croda Japan K.K.) was sufficiently dissolved. Next, 11.25g (130mmol to 140mmol) of formalin and 7.06g (75mmol) of phenol were added in small amounts stepwise, and the mixture was heated to 120 ℃ with stirring to remove the formed water and allowed to react for 3 hours. Thereafter, the reaction solution was cooled to room temperature. The cooled reaction solution was washed with methanol and then dried to obtain 8.3g of a benzoxazine compound which was a viscous liquid.

(curing accelerators)

Dimethylaminopyridine (DMAP available from Wako pure chemical industries, Ltd.)

2-phenyl-4-methylimidazole ("2P 4 MZ" manufactured by Siguo Kagaku Kogyo Co., Ltd., "anionic curing accelerator)

Dicumyl peroxide (Tokyo chemical industry Co., Ltd.)

(thermoplastic resin)

Polyimide compound (polyimide resin):

according to the following synthesis example 4, a solution containing a polyimide compound (nonvolatile content 26.8 wt%) as a reaction product of tetracarboxylic dianhydride and dimer diamine was synthesized.

(Synthesis example 4)

A reaction vessel equipped with a stirrer, a water separator, a thermometer, and a nitrogen gas inlet was charged with 300.0g of tetracarboxylic dianhydride ("BisDA-1000" manufactured by SABIC Japan K.K.) and 665.5g of cyclohexanone, and the solution in the reaction vessel was heated to 60 ℃. Next, 89.0g of dimer diamine ("PRIAMINE 1075" manufactured by Croda Japan K.K.) and 54.7g of 1, 3-bisaminomethylcyclohexane (manufactured by Mitsubishi Gas Chemical) were added dropwise to the reaction vessel. Then, 121.0g of methylcyclohexane and 423.5g of ethylene glycol dimethyl ether were added to the reaction vessel, and imidization was carried out at 140 ℃ for 10 hours. This gave a solution containing a polyamideimide compound (nonvolatile content: 26.8% by weight). The molecular weight (weight average molecular weight) of the obtained polyimide compound was 20000. The molar ratio of the acid component/the amine component was 1.04.

The molecular weight of the polyimide compound synthesized in synthesis example 4 was determined as follows.

GPC (gel permeation chromatography) assay:

the measurement was performed using a high performance liquid chromatography system manufactured by Shimadzu corporation using Tetrahydrofuran (THF) as a developing solvent under conditions of a column temperature of 40 ℃ and a flow rate of 1.0 ml/min. "SPD-10A" was used as a detector, and 2 columns were used by connecting "KF-804L" (excluding the limiting molecular weight of 400000) manufactured by Shodex Co., Ltd in series. As the Standard Polystyrene, "TSK Standard Polystyrene" manufactured by tokyo corporation was used, and calibration curves were prepared using materials having weight average molecular weights Mw of 354000, 189000, 98900, 37200, 17100, 9830, 5870, 2500, 1050, and 500, and the molecular weights were calculated.

(examples 1 to 14 and comparative examples 1 and 2)

The components shown in tables 1 to 4 below were mixed in the mixing amounts (in units of solid matter weight parts) shown in tables 1 to 4 below, and stirred at room temperature until a uniform solution was obtained, to obtain a resin material.

Preparation of resin film:

the obtained resin material was coated on a release-treated surface of a release-treated PET film ("XG 284" manufactured by Toray corporation, thickness 25 μm) by using a coater, and then dried in a gear oven at 100 ℃ for 2 minutes and 30 seconds to volatilize the solvent. Thus, a laminated film (laminated film of a PET film and a resin film) was obtained in which a resin film (B-stage film) having a thickness of 40 μm was laminated on a PET film.

(evaluation)

(1) Glass transition temperature of maleimide compound

Heating was performed from-30 ℃ to 200 ℃ at a heating rate of 3 ℃/min under a nitrogen atmosphere using a differential scanning calorimeter ("Q2000" manufactured by TA Instruments), and the glass transition temperature was determined from the inflection point of the reverse heat flow. The glass transition temperatures of the maleimide compounds A of examples 7 to 9 and 14 are shown in the tables.

(2) Embeddability into a concave-convex surface and prevention of protrusion (prevention of excessive wet diffusion)

Only the copper foil of a 100mm square copper-clad laminate (a laminate of a glass epoxy substrate having a thickness of 400 μm and a copper foil having a thickness of 25 μm) was etched, and recesses (openings) having a diameter of 100 μm and a depth of 25 μm were formed in a region 30mm square from the center of the substrate so as to be linear and that the center-to-center spacing between adjacent holes became 900 μm. Thus, an evaluation substrate having a total of 900 depressions was prepared.

The resin film side of the obtained laminated film was superposed on an evaluation substrate, and the film was heated and pressed at a lamination temperature of 90 ℃ and a lamination pressure of 0.4MPa for 20 seconds and at a lamination temperature of 90 ℃ and a pressing pressure of 0.8MPa for 20 seconds, by using "batch type vacuum laminator MVLP-500-IIA" manufactured by Kabushiki Kaisha. The PET film was peeled off after cooling at room temperature. Thus, an evaluation sample in which a resin film was laminated on an evaluation substrate was obtained.

The resulting evaluation sample was observed for voids in the pits using an optical microscope. The embeddability of the uneven surface was determined by evaluating the ratio of the observed depressions of the voids, according to the following criteria.

[ criterion for determining embeddability in a concave-convex surface ]

O: the ratio of the depression of the pores was observed to be 0%

And (delta): the ratio of dishing of the pores was observed to be more than 0% and less than 5%

X: the ratio of the observed voids to the depressions was 5% or more

The obtained evaluation sample was observed by using an optical microscope to see whether or not the resin film protruded from a specific region on the substrate, and the protrusion prevention property was judged by the following criteria.

[ determination criterion for prevention of protrusion ]

O: the protrusion of the resin film from the periphery of the evaluation substrate after lamination is 2mm or less

And (delta): the protrusion of the resin film after lamination from the peripheral portion of the evaluation substrate was more than 2mm and 3mm or less

X: the protrusion of the resin film from the peripheral portion of the evaluation substrate after lamination exceeded 3mm

(3) Thermal dimensional stability (average coefficient of linear expansion (CTE))

The obtained resin film (B-stage film) having a thickness of 40 μm was heated at 190 ℃ for 90 minutes to obtain a cured product, and the obtained cured product was cut into a size of 3mm × 25 mm. The average linear expansion coefficient (ppm/. degree. C.) of the cut cured product at 25 to 150 ℃ under the conditions of a tensile load of 33mN and a temperature rise rate of 5 ℃/min was calculated using a thermomechanical analyzer ("EXSTAR TMA/SS 6100" manufactured by SIInanotechnology Co., Ltd.).

[ criterion for determining average linear expansion coefficient ]

O ^ O: the average linear expansion coefficient is below 25 ppm/DEG C

O: the average linear expansion coefficient is more than 25 ppm/DEG C and less than 30 ppm/DEG C

X: the average linear expansion coefficient exceeds 30 ppm/DEG C

(4) Surface roughness after etching (surface roughness) and uniformity of surface roughness

Laminating and semi-curing:

a double-sided copper-clad laminate (CCL substrate) (E679 FG manufactured by hitachi chemical corporation) was prepared. Both surfaces of the copper foil surface of the double-sided copper-clad laminate were immersed in "Cz 8101" manufactured by Mec corporation, and the surface of the copper foil was roughened. On both sides of the roughened copper-clad laminate, the resin film (B-stage film) side of the laminate film was laminated on the copper-clad laminate by using "batch vacuum laminator MVLP-500-IIA" manufactured by the company name mechanism to obtain a laminated structure. The lamination conditions were reduced in pressure for 30 seconds to make the atmospheric pressure 13hPa or less, and then increased in pressure at 100 ℃ and 0.4MPa for 30 seconds. Thereafter, the resin film was semi-cured by heating at 180 ℃ for 30 minutes. This gives a laminate in which a semi-cured product of a resin film is laminated on a CCL substrate.

Roughening treatment:

(a) swelling treatment:

the obtained laminate was put into a Swelling solution ("spinning Dip Securigant P" manufactured by Atotech Japan corporation) at 60 ℃ and shaken for 10 minutes. Thereafter, the film was washed with pure water.

(b) Permanganate treatment (roughening treatment and desmearing treatment):

the laminate after the swelling treatment was put into a roughening aqueous solution of potassium permanganate ("Concentrate Compact CP" manufactured by Atotech Japan corporation) at 80 ℃ and shaken for 30 minutes. Next, the sample was treated with a 25 ℃ washing solution ("Reduction Securigint P" manufactured by Atotech Japan K.K.) for 2 minutes and then washed with pure water to obtain an evaluation sample.

Measurement of surface roughness:

on the surface of the evaluation sample (cured product subjected to roughening treatment), a region of 94 μm × 123 μm at 10 points was arbitrarily selected. For each of the 10 regions, the arithmetic mean roughness Ra was measured using a non-contact three-dimensional surface shape measuring apparatus ("WYKOnT 1100" manufactured by Veeco corporation). The following surface roughness was evaluated from the average value of the measured 10-point arithmetic average roughness Ra, and the uniformity of the following surface roughness was evaluated from the absolute value of the difference between the maximum value and the minimum value of the measured 10-point arithmetic average roughness Ra. The arithmetic average roughness Ra is measured in accordance with JIS B0601: 1994, to perform the assay.

[ criterion for determining surface roughness after etching ]

O ^ O: the average value of the arithmetic average roughness Ra is less than 80nm

O: the average value of the arithmetic average roughness Ra is more than 80nm and less than 120nm

X: the average value of the arithmetic average roughness Ra is 120nm or more

[ criterion for determining uniformity of surface roughness (surface roughness) after etching ]

O: the absolute value of the difference between the maximum value and the minimum value of the arithmetic average roughness Ra is less than 20nm

And (delta): the absolute value of the difference between the maximum value and the minimum value of the arithmetic average roughness Ra is more than 20nm and less than 30nm

X: the absolute value of the difference between the maximum value and the minimum value of the arithmetic average roughness Ra is 30nm or more

(5) Peel strength of plating

And (3) electroless plating treatment:

(4) the surface of the roughened cured product obtained in the evaluation of the surface roughness after etching (surface roughness) and the uniformity of the surface roughness was treated with an alkaline cleaning solution (Cleaner Securigant 902 manufactured by Atotech Japan K.K.) at 60 ℃ for 5 minutes, and then degreased and cleaned. After washing, the cured product was treated with a 25 ℃ Pre-dip solution ("Pre-dipneogenant B" manufactured by Atotech Japan K.K.) for 2 minutes. Thereafter, the cured product was treated with an activating solution ("activitornegagenant 834" manufactured by Atotech Japan K.K.) at 40 ℃ for 5 minutes, and a palladium catalyst was added thereto. Next, the cured product WAs treated with a reducing solution ("Reducerneogant WA" manufactured by Atotech Japan K.K.) at 30 ℃ for 5 minutes.

Next, the cured product was put into a chemical Copper solution ("Basic Printganth MSK-DK", "Copper Printganth MSK", "Stabilizer Printganth MSK", and "Reducer Cu" manufactured by Atotech Japan K.K.) and subjected to electroless plating until the plating thickness became about 0.5. mu.m. After the electroless plating, annealing treatment was performed at a temperature of 120 ℃ for 30 minutes in order to remove residual hydrogen. All steps before the step of electroless plating were performed while shaking the cured product by setting the volume of the treatment solution to 2L using a graduated beaker.

Plating treatment:

next, the cured product subjected to the electroless plating treatment was subjected to electroplating until the plating thickness became 25 μm. For electrolytic copper plating, a copper sulfate solution (copper sulfate pentahydrate manufactured by Wako pure chemical industries, Ltd., "sulfuric acid manufactured by Wako pure chemical industries, Ltd.," Basic leveler curracid HL manufactured by Atotech Japan K.K., "correction agent curracid GS manufactured by Atotech Japan K.K.) was used, and the flow rate was 0.6A/cm²The plating is performed with the current of (2) until the plating thickness becomes about 25 μm. After the copper plating treatment, the cured product was heated at 190 ℃ for 90 minutes to further cure the cured product. Thereby obtaining a cured product having a copper plating layer laminated on the upper surface.

Measurement of plating peel strength:

a short stripe-shaped cut having a width of 0.5cm was cut out on the surface of the obtained copper plating layer on which the cured product of the copper plating layer was laminated. The cured product having the copper plating layer laminated on the upper surface thereof was placed in a 90 ° peel TESTER ("TE-3001" manufactured by TESTER SANGYO corporation), the edge of the copper plating layer with the cut was pinched with a jig, and the copper plating layer was peeled 15mm to measure the peel strength (plating peel strength).

[ criterion for determining peeling Strength of plating ]

O ^ O: the plating peel strength is more than 0.5kgf

O: the plating peel strength is more than 0.3kgf and less than 0.5kgf

X: plating peel strength of less than 0.3kgf

(6) Dielectric loss tangent

The obtained resin film was cut into a size of 2mm in width and 80mm in length, and 5 sheets were stacked to obtain a laminate having a thickness of 200 μm. The obtained laminate was heated at 190 ℃ for 90 minutes to obtain a cured product. The resulting cured product was measured for dielectric loss tangent at a frequency of 1.0GHz at room temperature (23 ℃ C.) and at a high temperature (110 ℃ C.) by the cavity resonance method using "dielectric constant measuring apparatus CP521 by cavity resonance method" manufactured by Kanto electronics applications and "Network Analyzer 5224A PNA" manufactured by Keysit technologies. The dielectric loss tangent at high temperature (110 ℃ C.) was measured by placing the measurement site in a thermostatic bath.

The components and results are shown in tables 1 to 4 below.

Description of the symbols

A multilayer printed wiring board

12.. a circuit substrate

Upper surface 12a

13-16

A metal layer