JP5791983B2 - Resin composition, polyimide metal laminate using the same, and substrate for electronic circuit - Google Patents

Description

  The present invention relates to a resin composition having a low dielectric loss tangent, a polyimide metal laminate, and an electronic circuit substrate using the same.

  Conventionally, polyimide resins have been widely used in electronic devices and electronic parts such as circuit boards as insulating members that require high reliability because of their high insulating properties. In recent years, with the increase in the frequency of electrical signals in electronic devices, there has been a demand for low dielectric constant and low dielectric loss tangent of insulating members. In particular, the dielectric loss tangent has a greater contribution to the transmission characteristics than the relative dielectric constant, and the establishment of a method for reducing it is urgently required.

One method for reducing the dielectric loss tangent of a polyimide resin is to combine a polyimide resin and a material having a low dielectric loss tangent. Specifically, it is considered that a polyolefin resin having a low dielectric loss tangent is combined with a polyimide resin because it does not have a polar group.
However, a highly polar polyimide and a nonpolar polyolefin resin are not easily combined due to the difference in polarity. When combined, phase separation occurs and the smoothness of the resin surface decreases, and variations in dielectric properties occur, resulting in an increase in transmission loss of the electronic circuit. Therefore, this method is not realistic.

  Further, a method has been proposed in which a polyimide resin is made porous and the dielectric loss tangent or dielectric constant is lowered by the pores (see, for example, Patent Documents 1 to 3). However, when the polyimide resin is made porous, the mechanical strength of the polyimide resin is significantly reduced. Moreover, in a general manufacturing apparatus, it is difficult to make a polyimide resin porous, and capital investment is required.

In recent years, as a technique for reducing the dielectric constant of a polyimide resin, various techniques have been proposed for introducing caged silsesquioxane (POSS) into the polyimide resin (for example, Non-Patent Documents 1 to 4). . Furthermore, it has also been proposed to introduce POSS into a polyimide resin aiming at effects other than a reduction in dielectric constant, such as an adhesive improvement effect (for example, Patent Documents 4 and 5 and Non-Patent Document 5).
However, in these methods, although there is a report that the relative permittivity of the POSS nanopores is reduced as compared with the polyimide resin alone, there is no report that the dielectric loss tangent is successfully reduced.

JP 2003-201362 A JP 2000-154273 A Japanese Patent No. 3115215 JP 2002-322370 A JP 2005-105011 A

Journal of Applied Polymer Science, Vol. 99, 2226-2232 (2006). Chem. Mater., 2003, 15 (11), 2261-2265. Macromolecules 2007, 40, 5698-5705. Materials Chemistry and Physics 112 (2008) 1040-1046. Acta Materialia 57 (2009) 1112-1119.

There are two possible reasons why the dielectric loss tangent of the resin composition in which POSS is introduced into the polyimide resin does not decrease.
First, it is considered that the introduction of POSS into the polyimide resin reduces the packing property between the polyimide main chains. As a method of introducing POSS into the polyimide resin, a method of introducing a POSS skeleton into the polyimide main chain or grafting the POSS skeleton into the polyimide main chain is employed. According to these methods, since the nanopores possessed by POSS are introduced into the polyimide resin, it is considered that the dielectric loss tangent thereof is lowered. However, since POSS has a three-dimensional structure, when it is introduced into a polyimide resin, packing of polyimide main chains is hindered. Therefore, in the resin composition, the mobility of the polyimide main chain is increased, and the dielectric loss tangent is increased. Therefore, it is considered that the dielectric loss tangent of the resin composition cannot be lowered.

  In addition, when POSS is introduced into the polyimide resin, it is considered that a highly polar functional group is used. There are cases where the compatibility between the polyimide resin and the POSS is low, and in order to increase the compatibility, many techniques for introducing a highly polar functional group into the POSS have been adopted. However, since a polarization site such as a polar group rotates in an electric field, the dielectric loss tangent of the resin composition tends to increase. Furthermore, it is considered that the introduction of a highly polar functional group into the resin composition increases the hygroscopicity of the entire resin composition and increases the dielectric loss tangent due to the influence of water absorbed by the resin composition.

Thus, it has been difficult to achieve a low dielectric loss tangent of the polyimide resin without causing a significant decrease in mechanical strength or a decrease in surface smoothness due to phase separation. Further, even when POSS was introduced into the polyimide resin, the dielectric loss tangent did not decrease.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a resin composition having a low dielectric loss tangent and high surface smoothness, and a metal laminate using the same.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that a resin composition comprising a specific aromatic polyimide and a cage-shaped silsesquioxane partially-cleavage structure having a silanol group and a phenyl group. However, the inventors have found that a polyimide film having a low dielectric loss tangent and high surface smoothness can be formed, and the present invention has been completed.

  That is, according to the present invention, the following resin composition, polyimide metal laminate, and electronic circuit board are provided.

（一般式（Ａ−１）において、ｎは１〜３の整数である。）

（一般式（Ｂ）において、Ｘはフェニル、ビフェニル、トリフェニルより選ばれる４価の芳香族基である。）
［３］前記芳香族ジアミン化合物が、ｐ−フェニレンジアミンを含有し、前記芳香族テトラカルボン酸二無水物が、ピロメリット酸二無水物を含有し、前記芳香族ジアミン化合物と前記芳香族テトラカルボン酸二無水物の合計に対する、ｐ−フェニレンジアミンとピロメリット酸二無水物の合計の割合が５０ｍｏｌ％以上である［１］または［２］に記載の樹脂組成物。
［４］前記ジアミン化合物に含まれる前記芳香族ジアミン化合物以外のジアミン化合物が、その分子内で２以上の芳香環が１以上の原子を介して結合している部位を、少なくとも１以上有する化合物からなり、前記テトラカルボン酸二無水物に含まれる前記芳香族テトラカルボン酸二無水物以外のテトラカルボン酸二無水物が、その分子内で２以上の芳香環が１以上の原子を介して結合している部位を、少なくとも１以上有する化合物からなる、［１］〜［３］のいずれかに記載の樹脂組成物。
［５］１ＧＨｚにおける誘電正接が０．０１以下である［１］〜［４］のいずれかに記載の樹脂組成物。
［６］フィルム状とした際に、空気界面における１０点平均粗さ（Ｒｚ）が１μｍ以下である、［１］〜［５］のいずれかに記載の樹脂組成物。
［７］フィルム状とした際に、１００〜２００℃における熱膨張係数が２５ｐｐｍ／℃以下である［１］〜［６］のいずれかに記載の樹脂組成物。 [1] (a) An aromatic polyimide obtained by reacting a diamine compound containing an aromatic diamine compound and a tetracarboxylic dianhydride containing an aromatic tetracarboxylic dianhydride, the diamine compound and the tetra The ratio of the total of the aromatic diamine compound and the aromatic tetracarboxylic dianhydride to the total of carboxylic dianhydrides is 70 mol% or more, and the aromatic diamine compound or the aromatic tetracarboxylic dianhydride When two or more aromatic rings are linked in the molecule, the aromatic polyimide in which the aromatic rings are linked by a single bond, and (b) a bowl-like shape having a silanol group and a phenyl group A silsesquioxane partial cleavage structure, wherein the dielectric loss tangent is greater than the dielectric loss tangent of (a) the aromatic polyimide. There, the resin composition.
[2] The aromatic diamine compound is a compound represented by the following general formula (A-1), and the aromatic tetracarboxylic dianhydride is a compound represented by the following general formula (B). 1].

(In general formula (A-1), n is an integer of 1 to 3.)

(In the general formula (B), X is a tetravalent aromatic group selected from phenyl, biphenyl, and triphenyl.)
[3] The aromatic diamine compound contains p-phenylenediamine, the aromatic tetracarboxylic dianhydride contains pyromellitic dianhydride, the aromatic diamine compound and the aromatic tetracarboxylic The resin composition according to [1] or [2], wherein the ratio of the total of p-phenylenediamine and pyromellitic dianhydride to the total of acid dianhydride is 50 mol% or more.
[4] From a compound in which the diamine compound other than the aromatic diamine compound contained in the diamine compound has at least one site where two or more aromatic rings are bonded via one or more atoms in the molecule. The tetracarboxylic dianhydride other than the aromatic tetracarboxylic dianhydride contained in the tetracarboxylic dianhydride is bonded to two or more aromatic rings via one or more atoms in the molecule. The resin composition according to any one of [1] to [3], which comprises a compound having at least one site.
[5] The resin composition according to any one of [1] to [4], wherein a dielectric loss tangent at 1 GHz is 0.01 or less.
[6] The resin composition according to any one of [1] to [5], which has a 10-point average roughness (Rz) of 1 μm or less at the air interface when formed into a film.
[7] The resin composition according to any one of [1] to [6], which has a thermal expansion coefficient at 100 to 200 ° C. of 25 ppm / ° C. or less when formed into a film.

［９］難燃剤をさらに含む、［１］〜［８］のいずれかに記載の樹脂組成物。 [8] The partially cleaved silsesquioxane structure (b) having a silanol group and a phenyl group is a compound represented by the following general formula (1-a) [1] to [7] The resin composition in any one of.

[9] The resin composition according to any one of [1] to [8], further including a flame retardant.

[10] A polyimide metal laminate comprising an insulating layer made of the resin composition according to any one of [1] to [9] and a metal layer disposed on at least one surface of the insulating layer.
[11] An electronic circuit board comprising the polyimide metal laminate according to [10].
[12] The electronic circuit board according to [11], wherein the insulating layer is a flexible circuit board having a thickness of 50 μm or less.

  The resin composition of the present invention has a low dielectric loss tangent and high surface smoothness when formed into a film. For this reason, if the resin composition of the present invention is used, a polyimide metal laminate having high dielectric properties can be obtained, and an electronic circuit substrate with low transmission loss can be produced in a high frequency region.

  Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments.

1. Resin Composition The resin composition of the present invention comprises (a) an aromatic polyimide, and (b) a cage-shaped silsesquioxane partial cleavage structure having a silanol group and a phenyl group. The details will be described below.

(A) Aromatic polyimide (a) Aromatic polyimide contained in the resin composition of the present invention includes a diamine compound containing an aromatic diamine compound, a tetracarboxylic dianhydride containing an aromatic tetracarboxylic dianhydride, and It is obtained by reacting.

  (A) Aromatic polyimide has a high packing property of the polyimide main chain due to its structure. Therefore, the dielectric loss tangent can be lowered even though the (b) cage-shaped silsesquioxane partially-cleavage structure having a three-dimensional structure is mixed.

  In addition, the aromatic polyimide has a small amount of polar groups such as heteroatoms contained between two or more aromatic rings and has few polarization sites. For this reason, the dielectric loss tangent of the resin composition is rarely increased, and further, the hygroscopicity of the resin composition can be kept low, so that the increase of the dielectric loss tangent due to moisture absorption hardly occurs. Therefore, the dielectric loss tangent of the resin composition of the present invention can be very low.

上記一般式（Ａ）において、ｎは１〜３の整数である。 (A) The aromatic diamine compound used for the preparation of the aromatic polyimide is a diamine compound having an aromatic ring. However, when two or more aromatic rings are linked in the molecule, the aromatic rings are linked by a single bond. Moreover, it is preferable that the said aromatic ring does not have a substituent from a viewpoint of the packing property of aromatic polyimide. An example of the aromatic diamine compound is represented by the following general formula (A).

In the said general formula (A), n is an integer of 1-3.

  Examples of such an aromatic diamine compound include phenylenediamines such as m-phenylenediamine, o-phenylenediamine, and p-phenylenediamine; 1,3-bis (3-aminophenyl) benzene, 1,3-bis (4 -Aminophenyl) benzene, 1,4-bis (3-aminophenyl) benzene, 1,4-bis (4-aminophenyl) benzene, and other bis (aminophenyl) benzene. These aromatic diamine compounds can be used alone or in combination of two or more.

上記一般式（Ａ−１）において、ｎは１〜３の整数である。 Among these, from the viewpoint of the packing properties of the resulting aromatic polyimide, it is preferable to use a compound represented by the following general formula (A-1) as the aromatic diamine compound. Furthermore, it is preferable to use p-phenylenediamine.

In the said general formula (A-1), n is an integer of 1-3.

  (A) The aromatic tetracarboxylic dianhydride used for the preparation of the aromatic polyimide is a tetracarboxylic dianhydride having an aromatic ring. However, when two or more aromatic rings are connected in the molecule, the aromatic rings are connected by a single bond. Moreover, it is preferable that the said aromatic ring does not have a substituent from a viewpoint of the packing property of aromatic polyimide. Examples of such aromatic tetracarboxylic dianhydrides include aromatic tetracarboxylic dianhydrides represented by the following general formula (B).

上記一般式（Ｂ）において、Ｘはフェニル、ビフェニル、トリフェニルより選ばれる４価の芳香族基である。

In the general formula (B), X is a tetravalent aromatic group selected from phenyl, biphenyl, and triphenyl.

  Examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride, merophanic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′. 4,4'-biphenyltetracarboxylic dianhydride, 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride, and the like. These aromatic tetracarboxylic dianhydrides can be used singly or in combination of two or more.

  Among them, pyromellitic dianhydride and 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride are preferable from the viewpoint of packing properties of the resulting aromatic polyimide. Furthermore, it is preferable to use pyromellitic dianhydride.

  The aromatic diamine compound contains p-phenylenediamine, the aromatic tetracarboxylic dianhydride contains pyromellitic dianhydride, the aromatic diamine compound and the aromatic tetracarboxylic dianhydride. The ratio of the total of p-phenylenediamine and pyromellitic dianhydride to the total of the products is preferably 50 mol% or more, and more preferably 60 mol% or more. Since these compounds have only one aromatic ring and have a flat structure and are easy to pack as compared with a compound having a plurality of aromatic rings, the dielectric loss tangent is most lowered.

  (A) The ratio of the sum total of an aromatic diamine compound and aromatic tetracarboxylic dianhydride with respect to the sum total of the diamine compound and tetracarboxylic dianhydride used for preparation of an aromatic polyimide is 70 mol% or more. All of the diamine compound and the tetracarboxylic dianhydride may be an aromatic diamine compound and an aromatic tetracarboxylic dianhydride, respectively.

  However, in order to obtain the flexibility of (a) aromatic polyimide, a part of the diamine compound may be “other diamine compound” other than the aromatic diamine compound, or a part of the tetracarboxylic dianhydride may be aromatic. It is preferable to use “other tetracarboxylic dianhydrides” other than tetracarboxylic dianhydrides. The total of “other diamine compound” and “other tetracarboxylic dianhydride” is preferably 30 mol% or less with respect to the total of the diamine compound and tetracarboxylic dianhydride.

  (A) As an example of the other diamine compound used for preparation of an aromatic polyimide, the diamine compound which has an alicyclic structure, or the diamine compound which has an aromatic ring is mentioned. Examples of the diamine compound having an aromatic ring include a diamine compound containing one or more sites where two or more aromatic rings are bonded via one or more atoms in the molecule. In addition, a hetero atom may be sufficient as the atom which couple | bonds two or more aromatic rings.

  In the present invention, in particular, the “other diamine compound” is composed of a diamine compound having an aromatic ring, and the “other diamine compound” does not contain a diamine compound having an alicyclic structure. To preferred.

  Specific examples of “other diamine compounds” include the following diamine compounds (excluding the above aromatic diamine compounds).

  Examples of diamine compounds having an alicyclic structure include 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, 1,4-diaminomethylcyclohexane, 1,3-diaminomethylcyclohexane, 1,2-diaminomethylcyclohexane, 1,2-di (2-aminoethyl) cyclohexane, 1,3-di (2-aminoethyl) cyclohexane, 1,4-di (2-aminoethyl) cyclohexane, bis (4 -Aminocyclohexyl) methane, 2,6-bis (aminomethyl) bicyclo [2.2.1] heptane, 2,5-bis (aminomethyl) bicyclo [2.2.1] heptane, and the like. Of these, cyclohexanediamine such as 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, and 1,4-diaminocyclohexane is preferable. These diamine compounds having an alicyclic structure can be used singly or in combination of two or more.

  Examples of diamine compounds having an aromatic ring include 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, diaminodiphenyl ethers such as 4,4′-diaminodiphenyl ether; 3,3′-diaminodiphenyl sulfide, Diaminodiphenyl sulfides such as 4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfide; diaminos such as 3,3'-diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, and 4,4'-diaminodiphenylsulfone Diphenyl sulfone; diaminobenzophenone such as 3,3′-diaminobenzophenone; diaminodiphenylmethane such as 3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, and 4,4′-diaminodiphenylmethane;

  Bis (aminophenyl) propane such as 2,2-bis (3-aminophenyl) propane, 2,2-bis (4-aminophenyl) propane; 2,2-bis (3-aminophenyl) -1,1, Bis (aminophenyl) hexafluoropropane such as 1,3,3,3-hexafluoropropane, 2,2-bis (4-aminophenyl) -1,1,1,3,3,3-hexafluoropropane; 3,3′-diaminodiphenyl sulfoxide, 3,4′-diaminodiphenyl sulfoxide, diaminodiphenyl sulfoxide such as 4,4′-diaminodiphenyl sulfoxide; 1,3-bis (3-aminophenoxy) benzene, 1,3-bis Bis (aminophenoxy) benzene such as (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene;

  Bis (aminophenyl sulfide) benzene such as 1,3-bis (3-aminophenyl sulfide) benzene, 1,3-bis (4-aminophenyl sulfide) benzene, 1,4-bis (4-aminophenyl sulfide) benzene Bis (aminophenylsulfone) such as 1,3-bis (3-aminophenylsulfone) benzene, 1,3-bis (4-aminophenylsulfone) benzene, 1,4-bis (4-aminophenylsulfone) benzene; Benzene; bis (aminobenzyl) benzene such as 1,3-bis (3-aminobenzyl) benzene, 1,3-bis (4-aminobenzyl) benzene, 1,4-bis (4-aminobenzyl) benzene; 1 Bis (aminophenoxybenzoyl) benzene such as 1,3-bis (3-amino-4-phenoxybenzoyl) benzene;

  3,3′-bis (3-aminophenoxy) biphenyl, 3,3′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, 4,4′-bis (4 Bis (aminophenoxy) biphenyl such as 2-aminophenoxy) biphenyl; bis [3- (3-aminophenoxy) phenyl] ether, bis [3- (4-aminophenoxy) phenyl] ether, bis [4- (3-amino Bis [(aminophenoxy) phenyl] ether such as phenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ether; bis [3- (3-aminophenoxy) phenyl] ketone, bis [3- ( 4-aminophenoxy) phenyl] ketone, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) phenyl] ketone Bis [(aminophenoxy) phenyl] ketone; bis [3- (3-aminophenoxy) phenyl] sulfide, bis [3- (4-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl ] Bis [(aminophenoxy) phenyl] sulfide such as sulfide, bis [4- (4-aminophenoxy) phenyl] sulfide; bis [3- (3-aminophenoxy) phenyl] sulfone, bis [3- (4-amino Bis [(aminophenoxy) phenyl] sulfone such as phenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] sulfone;

  Bis [3- (3-aminophenoxy) phenyl] methane, bis [3- (4-aminophenoxy) phenyl] methane, bis [4- (3-aminophenoxy) phenyl] methane, bis [4- (4-amino Bis [(aminophenoxy) phenyl] methane such as phenoxy) phenyl] methane; 2,2-bis [3- (3-aminophenoxy) phenyl] propane, 2,2-bis [3- (4-aminophenoxy) phenyl Bis [(aminophenoxy) phenyl] propane such as propane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane; 2,2-bis [3- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [3- (4-aminophenoxy) phenyl]- 1,1,1,3,3, -Hexafluoropropane, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [4- (4-amino Bis [(aminophenoxy) phenyl] hexafluoropropane such as phenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane;

  9,9-bis (4-aminophenyl) fluorene, 9,9-bis (2-methyl-4-aminophenyl) fluorene, 9,9-bis (3-methyl-4-aminophenyl) fluorene, 9,9 -Bis (2-ethyl-4-aminophenyl) fluorene, bis (aminophenyl) fluorene such as 9,9-bis (3-ethyl-4-aminophenyl) fluorene; 9,9-bis (4-aminophenyl) -1-methylfluorene, 9,9-bis (4-aminophenyl) -2-methylfluorene, 9,9-bis (4-aminophenyl) -3-methylfluorene, 9,9-bis (4-aminophenyl) And bis (aminophenyl) methylfluorene such as 4-methylfluorene.

  Among these, 4,4′-diaminodiphenyl ether and 4,4′-bis (3-aminophenoxy) biphenyl are preferable from the viewpoint of flexibility of the resulting polyimide. These diamine compounds having an aromatic ring can be used singly or in combination of two or more.

  (A) Examples of other tetracarboxylic dianhydrides used for the preparation of aromatic polyimide include tetracarboxylic dianhydrides having an alicyclic structure or tetracarboxylic dianhydrides having an aromatic ring. . Examples of tetracarboxylic dianhydrides having aromatic rings include tetracarboxylic dianhydrides containing one or more sites where two or more aromatic rings are bonded via one or more atoms in the molecule. . In addition, a hetero atom may be sufficient as the atom which couple | bonds two or more aromatic rings.

In the present invention, in particular, the “other tetracarboxylic dianhydride” is composed of a tetracarboxylic dianhydride having an aromatic ring, and the “other tetracarboxylic dianhydride” is a tetracarboxylic dianhydride having an alicyclic structure. It is preferable not to contain an anhydride from the viewpoint of polyimide packing properties.
Specific examples of “other tetracarboxylic dianhydrides” include the following tetracarboxylic dianhydrides (excluding the above aromatic tetracarboxylic dianhydrides).

  Other tetracarboxylic dianhydrides are preferably tetracarboxylic dianhydrides having an aromatic ring, and examples of tetracarboxylic dianhydrides having an aromatic ring include 3,3 ′, 4,4′-benzophenone. Tetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (2,3-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) sulfide dianhydride , Bis (3,4-dicarboxyphenyl) sulfone dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, 1,3-bis (3,4-dicarboxyphenoxy) benzene Dianhydride, 1,4-bis (3, -Dicarboxyphenoxy) benzene dianhydride, 1,4-bis (3,4-dicarboxyphenoxy) biphenyl dianhydride, 2,2-bis [(3,4-dicarboxyphenoxy) phenyl] propane dianhydride Etc. These tetracarboxylic dianhydrides having an aromatic ring can be used singly or in combination of two or more.

(B) Partially-cleavage structure of silsesquioxane The partially-cleavage structure of a cage-like silsesquioxane contained in the resin composition of the present invention has a silanol group and a phenyl group. The partially cleaved structure is a silicon compound formed by cleaving a part of silicon (Si) -oxygen (O) bond in a cage-like silsesquioxane.

More specifically, a part of silicon (Si) -oxygen (O) of the cage-shaped silsesquioxane represented by the general formula [XSiO _3/2 ] _n (n represents an integer of 6 to 14). Silicon represented by the general formula [XSiO _3/2 ] _nm (O _1/2 H) _{2 + m} (n represents an integer of 6 to 14, and m represents 0 or 1) formed by cleavage of the bond A compound.

(B) As a partial cleavage structure of silsesquioxane, a trisilanol body represented by the general formula [XSiO _3/2 ] ₇ (O _1/2 H) ₃ (the following general formula (1)), a general formula A trisilanol body represented by [XSiO _3/2 ] ₉ (O _1/2 H) ₃ (the following general formula (4)), represented by a general formula [XSiO _3/2 ] ₁₁ (O _1/2 H) ₃ A trisilanol body (the following general formula (5)), a disilanol body represented by the general formula [XSiO _3/2 ] ₈ (O _1/2 H) ₂ (the following general formulas (2) and (3)). Further preferred is a trisilanol body represented by the general formula [XSiO _3/2 ] ₇ (O _1/2 H) ₃ (the following general formula (1)). In the following general formulas (1) to (5), “X” and “OH” bonded to the same silicon atom (Si) may exchange positions with each other. These partial cleavage structures of silsesquioxane can be used singly or in combination of two or more.

  X in the general formulas (1) to (5) each independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or carbon. They are an aralkyl group having 7 to 20 carbon atoms and an aryl group having 6 to 20 carbon atoms. However, at least 1 or more X is a phenyl group. By having a phenyl group as X, the compatibility with the above-mentioned (a) aromatic polyimide is improved.

  Specific examples of the “alkyl group having 1 to 20 carbon atoms” include methyl group, ethyl group, propyl group, n-butyl group, i-butyl group, t-butyl group, pentyl group, i-pentyl group and neopentyl group. N-hexyl group, i-hexyl group, n-heptyl group, i-heptyl group, n-octyl group, i-octyl group, n-nonyl group, i-nonyl group, n-decyl group, i-decyl group N-undecyl group, i-undecyl group, n-dodecyl group, i-dodecyl group and the like.

  Specific examples of the “C6-C20 cycloalkyl group” include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a methylcyclopentyl group, a methylcyclohexyl group, and the like.

  Specific examples of the “alkenyl group having 2 to 20 carbon atoms” include vinyl group, propenyl group, butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, undecenyl group, dodecenyl group, cyclohexane A hexenyl group, a cyclohexenylethyl group, a norbornenylethyl group, etc. can be mentioned.

  Specific examples of the “aralkyl group having 7 to 20 carbon atoms” include benzyl group, phenethyl group, 2-methylbenzyl group, 3-methylbenzyl group, 4-methylbenzyl group, 2,6-dimethylbenzyl group, 2, 4-dimethylbenzyl group, 2,5-dimethylbenzyl group, 2-ethylbenzyl group, 3-ethylbenzyl group, 4-ethylbenzyl group, 2-methylphenethyl group, 3-methylphenethyl group, 4-methylphenethyl group, 2-propylbenzyl group, 3-propylbenzyl group, 4-propylbenzyl group, 2-ethyl-6-methylbenzyl group, 2-ethyl-5-methylbenzyl group, 2-ethyl-4-methylbenzyl group, 6- Ethyl-2-methylbenzyl group, 5-ethyl-2-methylbenzyl group, 4-ethyl-2-methylbenzyl group, 2,6-dimethylphenethyl group, 2,5-dimethylphenethyl group, 2,4-dimethylphene Group, 2-ethylphenethyl group, 3-ethylphenethyl group, 4-ethylphenethyl group, 2,6-diethylbenzyl group, 2,5-diethylbenzyl group, 2,4-diethylbenzyl group, 2-ethyl-6 -Methylphenethyl group, 2-ethyl-5-methylphenethyl group, 2-ethyl-4-methylphenethyl group, 6-ethyl-2-methylphenethyl group, 5-ethyl-2-methylphenethyl group, 4-ethyl-2 -Methylphenethyl group, 2,6-diethylphenethyl group, 2,5-diethylphenethyl group, 2,4-diethylphenethyl group and the like can be mentioned.

  Specific examples of the “C6-C20 aryl group” include a phenyl group, a phenyl group mono- or multi-substituted with an alkyl group having 1 to 14 carbon atoms (preferably 1 to 8 carbon atoms), and the like. it can.

  X in the general formulas (1) to (5) is preferably an ethyl group, a cyclohexyl group, a cyclopentyl group, a phenyl group, an isobutyl group, or an isooctyl group, and more preferably all Xs are phenyl groups.

Further, a compound represented by the following general formula (1-a), in which all Xs in the general formula (1) are phenyl groups, is particularly preferable.

  The (b) silsesquioxane partially-cleavage structure may be a dimer or higher multimer formed by a condensation reaction between silanol groups, and is represented by the general formulas (1) to (5). You may use it in combination with the monomer represented by these.

  Generally, when preparing a composite material of silsesquioxane (non-cleavable structure) and polyimide, the dispersibility of silsesquioxane in polyimide is low, and silsesquioxane is uniformly dispersed in polyimide. It is difficult to do. On the other hand, the partially cleaved structure of (b) silsesquioxane used in the present invention has high dispersibility in the above-mentioned (a) aromatic polyimide.

  (B) The silsesquioxane partially-cleavage structure is formed by cleavage of a part of the silicon (Si) -oxygen (O) covalent bond of the silsesquioxane, and has a silanol group in its molecular structure. Furthermore, the partial cleavage structure of (b) silsesquioxane has a phenyl group. It is estimated that the dispersibility with respect to the above-mentioned (a) aromatic polyimide is improved by the silanol group and the phenyl group.

  In addition, (b) the silsesquioxane partially cleaved structure is a compound in which only a part of the silicon (Si) -oxygen (O) covalent bond of silsesquioxane is cleaved. Nano-sized voids are retained. For this reason, the resin composition of this invention containing the partial cleavage structure of (b) silsesquioxane has a low dielectric loss tangent. The resin composition of the present invention has (b) a silsesquioxane partially-cleavage structure relatively uniformly dispersed, so that the surface smoothness is high, and transmission loss when used as an electronic circuit board. The remarkable effect that it is possible to reduce is shown.

  The amount of the (b) silsesquioxane partially-cleavage structure contained in the resin composition of the present invention is preferably 10 to 300 parts by weight with respect to 100 parts by weight of (a) polyimide. More preferably, it is 200 parts by weight.

(C) Other components In addition to (a) aromatic polyimide and (b) silsesquioxane partially-cleavage structure, the resin composition of the present invention includes other components as necessary within the range not impairing the object of the present invention. The component may be contained.
Examples of other components include various additives such as fillers, flame retardants, heat stabilizers, oxidation stabilizers, and light stabilizers.

  Examples of the flame retardant include an organic halogen flame retardant; a combination of an organic halogen flame retardant and one or more selected from the group consisting of antimony oxide, zinc borate, zinc stannate, and iron oxide; Combination of flame retardant and silicone compound; inorganic phosphorus such as red phosphorus; combination of organopolysiloxane and organometallic compound; hindered amine flame retardant; inorganic flame retardant such as magnesium hydroxide, alumina, calcium borate, and low-melting glass Etc. are included. These flame retardants may be used alone or in combination of two or more.

  Examples of the organic halogen flame retardant include at least one compound selected from the group consisting of a halogenated bisphenol compound, a halogenated epoxy compound, and a halogenated triazine compound. The halogen atom contained in the organic halogen flame retardant is preferably at least one of bromine and chlorine from the viewpoint of effectively increasing the flame retardancy of the resin. Examples of such halogenated bisphenol compounds include tetrabromobisphenol A, dibromobisphenol A, tetrachlorobisphenol A, dichlorobisphenol A, tetrabromobisphenol F, dibromobisphenol F, tetrachlorobisphenol F, dichlorobisphenol F, tetrabromo. Bisphenol S, dibromobisphenol S, tetrachlorobisphenol S, dichlorobisphenol S and the like are included.

  The organophosphorus flame retardant is preferably at least one of a phosphate compound and a phosphazene compound. Examples of phosphate compounds include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, triphenyl phosphate, tricresyl phosphate, trixyl phosphate, cresyl diphenyl phosphate, xylyl diphenyl phosphate, tolyl dixyl phosphate, tris ( Norylphenyl) phosphate and phosphate esters such as (2-ethylhexyl) diphenyl phosphate; Resorcinol diphenyl phosphate and hydroxyl group-containing phosphate esters such as hydroquinone diphenyl phosphate; Resorcinol bis (diphenyl phosphate), hydroquinone bis (diphenyl phosphate), bisphenol -A bis (diphenyl phosphate), bisphenol -S bis (diphenyl phosphate), resorcinol bis (dixyl phosphate), hydroquinone bis (dixyl phosphate), bisphenol-A bis (ditolyl phosphate), biphenol-A bis (dixyl phosphate), and bisphenol-S bis ( Condensed phosphate ester compounds such as dixylyl phosphate; phosphine or phosphine oxide compounds such as trilauryl phosphine, triphenyl phosphine, tolyl phosphine, triphenyl phosphine oxide, and tolyl phosphine oxide.

  Examples of phosphazene compounds include hexaphenoxycyclotriphosphazene, monophenoxypentakis (4-cyanophenoxy) cyclotriphosphazene, diphenoxytetrakis (4-cyanophenoxy) cyclotriphosphazene, triphenoxytris (4-cyanophenoxy) cyclo Triphosphazene, tetraphenoxybis (4-cyanophenoxy) cyclotriphosphazene, pentaphenoxy (4-cyanophenoxy) cyclotriphosphazene, monophenoxypentakis (4-methoxyphenoxy) cyclotriphosphazene, diphenoxytetrakis (4-methoxyphenoxy) ) Cyclotriphosphazene, triphenoxytris (4-methoxyphenoxy) cyclotriphosphazene, tetraphenoxybis (4-methoxyphenoxy) cyclo Riphosphazene, pentaphenoxy (4-methoxyphenoxy) cyclotriphosphazene, monophenoxypentakis (4-methylphenoxy) cyclotriphosphazene, diphenoxytetrakis (4-methylphenoxy) cyclotriphosphazene, triphenoxytris (4-methylphenoxy) ) Cyclotriphosphazene, tetraphenoxybis (4-methylphenoxy) cyclotriphosphazene, pentaphenoxy (4-methylphenoxy) cyclotriphosphazene, triphenoxytris (4-ethylphenoxy) cyclotriphosphazene, triphenoxytris (4-propyl) Phenoxy) cyclotriphosphazene, monophenoxypentakis (4-cyanophenoxy) cyclotriphosphazene, diphenoxytetrakis (4-hydroxypheno) C) Cyclotriphosphazene, triphenoxytris (4-hydroxyphenoxy) cyclotriphosphazene, tetraphenoxybis (4-hydroxyphenoxy) cyclotriphosphazene, pentaphenoxy (4-hydroxyphenoxy) cyclotriphosphazene, triphenoxytris (4- Phenylphenoxy) cyclotriphosphazene, triphenoxytris (4-methacrylphenoxy) cyclotriphosphazene, triphenoxytris (4-acrylphenoxy) cyclotriphosphazene, and the like.

  Examples of heat stabilizers and oxidation stabilizers include trade names “Irganox” and trade names “Irgaphos” manufactured by Ciba Specialty Chemicals. Examples of the light-resistant stabilizer include trade name “TINUVIN” and trade name “CHIMASSORB” manufactured by Ciba Specialty Chemicals.

(D) Physical property of resin composition The dielectric loss tangent of the resin composition of this invention is low compared with the dielectric loss tangent of the (a) aromatic polyimide contained in the resin composition. The dielectric loss tangent of the resin composition is lower than the dielectric loss tangent of (a) aromatic polyimide means that the dielectric loss tangent of the resin composition is lower than the dielectric loss tangent of (a) aromatic polyimide by 0.0001 or more, It is preferably 0.0005 or lower, and more preferably 0.001 or lower.

  The dielectric loss tangent is a value (tan δ) measured at a temperature of 23 ° C., a relative humidity of 60%, and a measurement frequency of 1 GHz by the perturbation type cavity resonator method.

  The dielectric loss tangent at 1 GHz of the resin composition of the present invention is preferably 0.01 or less, more preferably 0.008 or less, and still more preferably 0.007 or less. By setting the dielectric loss tangent of the resin composition to 0.01 or less, the resin composition of the present invention can be used as an insulating material for various electronic devices and electronic components.

  The resin composition of the present invention preferably has a thermal expansion coefficient at 100 to 200 ° C. of 25 ppm / ° C. or less, more preferably 20 ppm / ° C. or less, and further preferably 15 ppm / ° C. or less when it is formed into a film. . Thus, since the thermal expansion coefficient of the film (polyimide film) made of the resin composition of the present invention is small, for example, a metal layer and a laminate made of a metal such as copper (thermal expansion coefficient: about 17 ppm / ° C.) were formed. In such a case, warpage and distortion based on the difference in thermal expansion hardly occur, and the temperature stability is excellent. In addition, although it does not specifically limit about the lower limit of the thermal expansion coefficient at the time of using a resin composition as a film, Usually, it is about 5 ppm / degreeC. The thermal expansion coefficient is measured in the range of 100 to 200 ° C. in a dry air atmosphere using a thermal analyzer. The thermal expansion coefficient can be adjusted by the functional group of (a) an aromatic polyimide skeleton and (a) a partial cleavage structure of (a) aromatic polyimide and (b) silsesquioxane.

  The resin composition of the present invention has a high surface smoothness when formed into a film because the partially cleaved structure of (b) silsesquioxane is relatively uniformly dispersed in (a) aromatic polyimide. . Specifically, when the resin composition of the present invention is formed into a film, the 10-point average roughness (Rz) at the air interface of this film can be 1 μm or less, more preferably 0.5 μm or less. And By setting the 10-point average roughness when made into a film to 1 μm or less, it can be applied to an electronic circuit substrate with a small transmission loss of electric signals.

  The 10-point average roughness (Rz) at the air interface of the film is measured by the method defined in JIS B-0601. The cut-off value is 0.20 mm and the measurement length is 2.0 mm. This is a value obtained by measurement.

(E) Method for Producing Resin Composition The method for producing the resin composition of the present invention is not particularly limited. For example, a diamine compound containing an aromatic diamine compound and a tetracarboxylic dianhydride containing an aromatic tetracarboxylic dianhydride. The product is reacted in a solvent to form a polyamic acid varnish. This polyamic acid varnish, (b) a silsesquioxane partially-cleavage structure, and, if necessary, other components are mixed and heated to polyimidize the polyamic acid.

  The molar ratio (preparation ratio) of tetracarboxylic dianhydride and diamine compound to be reacted when preparing the polyamic acid is M1: M2 = 0.000-0.999: 1.00 (M1: tetracarboxylic acid). The number of moles of the dianhydride component, M2: the number of moles of the diamine compound) is preferable. Thereby, the main chain of the polyamic acid obtained can be made into an amine terminal. M1: M2 is more preferably 0.92 to 0.995: 1.00, particularly preferably 0.95 to 0.995: 1.00, and 0.97 to 0.995: A value of 1.00 is particularly preferable.

  The diamine compound and tetracarboxylic dianhydride may be reacted in a solvent. Although the kind of solvent is not particularly limited, a solvent capable of dissolving a monomer or the like used for preparing polyimide acid or polyamic acid is preferable, an aprotic polar solvent is more preferable, and an aprotic amide solvent is particularly preferable. Specific examples of the aprotic amide solvent include N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazo. Lysinone and the like can be mentioned. These solvents can be used alone or in combination of two or more.

  In addition, “other solvents” other than the above aprotic amide solvents can be used as necessary. Specific examples of “other solvents” include benzene, toluene, o-xylene, m-xylene, p-xylene, o-chlorotoluene, m-chlorotoluene, p-chlorotoluene, o-bromotoluene, m-bromo. Examples include toluene, p-bromotoluene, chlorobenzene, bromobenzene, methanol, ethanol, n-propanol, isopropyl alcohol, and n-butanol.

  The amount of the solvent contained in the polyamic acid varnish is preferably such that the concentration of the resin solid content (polyamic acid) is 1 to 40% by weight, and more preferably 10 to 30% by weight. .

  Further, as a method of mixing the polyamic acid varnish, (b) a silsesquioxane partial cleavage structure, and other components as necessary, (b) partial cleavage of silsesquioxane in polyamic acid The method is not particularly limited as long as the structure can be uniformly dispersed, and can be kneaded using a general kneader.

  There is no restriction | limiting in particular also about the polyimidation method of polyamic acid. For example, after applying a mixture of the above-mentioned polyamic acid and the (b) silsesquioxane partially-cleavage structure to the surface of a glass substrate or the like to form a thin film, it is heated to imidize (ring-close) and solvent It can be produced by removing or the like. The heating temperature may be equal to or higher than the temperature at which imidization proceeds, but (b) it is preferably heated to the melting point or higher of the partial cleavage structure of silsesquioxane, specifically 250 to 400 ° C. Is preferred. (B) By heating the silsesquioxane partially-cleavage structure to the melting point or higher, silanol groups react with each other to form a silica bond, so that the dielectric loss tangent of the resin composition can be reduced.

  The imidization of the polyamic acid is usually performed under atmospheric pressure conditions, but may be performed under pressurized conditions. The atmosphere for imidizing the polyamic acid is not particularly limited, but is usually air, nitrogen, helium, neon, or an argon atmosphere, and preferably imidized in an inert gas nitrogen or argon atmosphere.

  The shape in particular of the resin composition of this invention is not restrict | limited, According to the use etc. of a resin composition, it selects suitably, According to the above-mentioned method, although it can be set as a film form, it is not limited to this. By using a film shape, it can be used as an insulating layer or the like in a metal laminate described later.

2. Polyimide metal laminate and electronic circuit board The polyimide laminate of the present invention comprises an insulating layer made of the resin composition described above and a metal layer (conductor layer) disposed on at least one surface of the insulating layer. . In addition, the metal layer may be arrange | positioned on both surfaces of an insulating layer, and may be provided with several insulating layers. The polyimide metal laminate of the present invention includes an insulating layer having a high surface smoothness, which is made of a resin composition having a low dielectric loss tangent and a high heat resistance. For this reason, the polyimide metal laminate of the present invention is preferably used as various electronic circuit substrates, particularly as high-frequency circuit substrates.

  Specific examples of the metal constituting the metal layer include copper, aluminum, nickel, gold, silver, and stainless steel. Among these, copper is preferable from the viewpoint of high conductivity. Although the thickness of a metal layer is not specifically limited, Usually, it is 2-150 micrometers, Preferably it is 3-50 micrometers. Moreover, although it does not specifically limit about the thickness of an insulating layer, Usually, 5-100 micrometers, Preferably it is 10-50 micrometers.

The polyimide metal laminate of the present invention can be produced by, for example, the following methods (1) to (3).
(1) A method of thermocompression bonding a film made of the above resin composition and a metal foil (2) A method of forming a metal layer on the surface of the film made of the above resin composition by sputtering, vapor deposition or the like (3) ) After applying a mixture of the above-mentioned polyamic acid varnish, (b) silsesquioxane partially-cleavage structure, and other components as required on the surface of the metal foil, the polyamide is heated Method of imidizing acid to form polyimide film

  In addition, although the thermocompression bonding temperature in the method (1) depends on the combination of the polyimide and the metal foil contained in the resin composition, it is preferably not less than the glass transition temperature of the polyimide, specifically 130- It is preferable that the temperature is about 400 ° C.

The electronic circuit board of the present invention has an insulating layer having high heat resistance and low dielectric constant. For this reason, the electronic circuit board of the present invention is widely used in various applications using high frequency such as electronic components having a high frequency circuit, for example, a built-in antenna of a mobile phone, an antenna of a vehicle-mounted radar, and a high-speed wireless communication for home use. Applicable.
In particular, by setting the thickness of the insulating layer to 50 μm or less, a flexible circuit board can be obtained, which can be widely applied to the various uses described above.

  EXAMPLES Next, although this invention is demonstrated in detail based on an Example, this invention is not limited to these Examples.

1. Various ingredients used (abbreviations)
(1) Component of polyamic acid (1-1) Diamine compound CHDA: trans 1,4-diaminocyclohexane mBP: 4,4′-bis (3-aminophenoxy) biphenyl PDA: p-phenylenediamine ODA: 4, 4 '-Diaminodiphenyl ether

(1-2) Tetracarboxylic dianhydride BPDA: 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride PMDA: pyromellitic dianhydride

(2) Silsesquioxane and its partial cleavage structure (POSS)
SO1458 (manufactured by Hybrid Plastic Co.): compound represented by the following general formula (1) (X = phenyl group)
SO1450 (manufactured by Hybrid Plastics): Compound represented by the following general formula (1) (X = i-butyl group)
MS0840 (manufactured by Hybrid Plastics): compound represented by the general formula [XSiO _3/2 ] ₈ (X = phenyl group)

(3) Solvent DMAc: N, N-dimethylacetamide NMP: N-methyl-2-pyrrolidone

2. Preparation of polyamic acid (Preparation of polyamic acid A)
To a container equipped with a stirrer and a nitrogen introduction tube, 261.0 g of DMAc was added as a solvent, and 20.44 g of ODA and 16.12 g of mBP were further added thereto, followed by stirring at 20 to 30 ° C. Dissolved. Next, 30.84 g of PMDA was added, and the material adhering to the inside of the flask was washed off with 11.0 g of DMAc, heated to 50 to 60 ° C., and stirred for about 1 hour. Thereafter, 0.44 g of PMDA was further added, and the mixture was stirred for about 4 hours while maintaining the temperature at 60 ° C. to obtain a varnish of polyamic acid A1.

  On the other hand, 263.0 g of NMP was added as a solvent to a container equipped with another stirrer and a nitrogen introduction tube, 19.62 g of PDA was added, and the mixture was stirred and dissolved at 20 to 30 ° C. Thereafter, 37.0 g of BPDA and 11.06 g of PMDA were further added, and the raw material adhering to the inside of the flask was washed off with 10.0 g of NMP, heated to 50 to 60 ° C., stirred for about 4 hours, and polyamic acid A2 The varnish was obtained.

  Then, in a container equipped with another stirrer and a nitrogen introduction tube, the varnish of the polyamic acid A2 and the varnish of the polyamic acid A1 are mixed in a weight ratio of (A2) :( A1) = 93: 7, The mixture was heated to 50 to 60 ° C. and stirred for about 4 hours to obtain a polyamic acid A varnish. The resulting varnish of polyamic acid A had a polyamic acid A content of 20% by weight and an E-type viscosity at 25 ° C. of 30000 mPa · s. The ratio of the sum total of the aromatic diamine compound and aromatic tetracarboxylic dianhydride of Claim 1 with respect to the sum total of a diamine compound and tetracarboxylic dianhydride is 97 mol%.

(Preparation of polyamic acid B)
A container equipped with a stirrer and a nitrogen introduction tube was charged with 20.55 g of PDA and 301 g of NMP as a solvent, and the temperature of the solution was raised to 50 ° C. and stirred until PDA was dissolved. After the temperature of the solution was lowered to room temperature, 55.34 g of BPDA was added over about 30 minutes, 129 g of NMP was further added, and the mixture was stirred for 20 hours to obtain a polyamic acid B varnish. The solid content of the polyamic acid B was 15% by weight, and the logarithmic viscosity was 1.3 dl / g. The ratio of the sum total of the aromatic diamine compound and aromatic tetracarboxylic dianhydride of Claim 1 with respect to the sum total of a diamine compound and tetracarboxylic dianhydride is 100 mol%.

(Preparation of polyamic acid C)
A container equipped with a stirrer and a nitrogen introduction tube was charged with 24.03 g of ODA and 139.5 g of DMAc as a solvent, and stirred until ODA was dissolved. Next, 25.78 g of PMDA was added to this solution over about 30 minutes, and 103.7 g of DMAc was further added thereto, followed by stirring for 20 hours to obtain a polyamic acid C varnish. The polyamic acid C had a solid content of 17% by weight and a logarithmic viscosity of 1.2 dl / g. The ratio of the sum total of the aromatic diamine compound and aromatic tetracarboxylic dianhydride of Claim 1 with respect to the sum total of a diamine compound and tetracarboxylic dianhydride is 49.6 mol%.

(Preparation of polyamic acid D)
CHDA (14.84 g) was placed in a reaction vessel equipped with a stirrer and a nitrogen introducing tube, dissolved in 341 g of NMP, and then 37.87 g of BPDA powder was added with stirring to obtain a white suspension. The obtained suspension was vigorously stirred at 100 ° C. for 12 minutes in an oil bath, whereby the solid content in the container was dissolved to obtain a transparent viscous liquid. After removing the reaction vessel from the oil bath, 85 g of NMP was added and stirred at room temperature for 10 hours to obtain a varnish of polyamic acid D. The solid content of the polyamic acid solid content D was 11% by weight, and the logarithmic viscosity was 1.50 dl / g. The ratio of the sum total of the aromatic diamine compound and aromatic tetracarboxylic dianhydride of Claim 1 with respect to the sum total of a diamine compound and tetracarboxylic dianhydride is 49.8 mol%.

3. Preparation of polyimide film (Example 1)
A varnish of polyamic acid A and SO1458 were charged into a plastic container so that SO1458 was 100 parts by weight with respect to 100 parts by weight of polyamic acid solids. Furthermore, 400 parts by weight of NMP was added so that the solid content of the polyamic acid composition was 20% by weight. These were mixed using a kneader to prepare a polyamic acid composition.
The prepared polyamic acid composition was applied on a glass plate with a baker applicator so that the dry film thickness was about 30 μm. The temperature of the coating film was raised to 300 ° C. over 2 hours in an inert oven over 2 hours and further heated at 300 ° C. for 2 hours for imidization. The glass plate on which the coating film was formed was immersed in water at about 40 ° C., and the coating film was peeled off from the glass plate to obtain a polyimide film (film made of the resin composition of the present invention) having a thickness of about 30 μm.

(Example 2)
In a plastic container, a varnish of polyamic acid A, SO1458 and a flame retardant (RABITOL FP-300 manufactured by Fushimi Pharmaceutical Co., Ltd.), SO1458 and a flame retardant of 36 wt. Part and 18 parts by weight. Further, 216 parts by weight of NMP was added so that the solid content of the polyamic acid composition was 20% by weight. These were mixed using a kneader to prepare a polyamic acid composition. This was imidized in the same manner as in Example 1 to obtain a polyimide film (film comprising the resin composition of the present invention).

(Example 3)
A polyimide film (film made of the resin composition of the present invention) was obtained in the same manner as in Example 1 except that the polyamic acid varnish was changed from polyamic acid A to polyamic acid B.

(Comparative Example 1)
A polyimide film was obtained in the same manner as in Example 1 except that the polyamic acid varnish was changed from polyamic acid A to polyamic acid C.

(Comparative Example 2)
A polyimide film was obtained in the same manner as in Example 1 except that the polyamic acid varnish was changed from polyamic acid A to polyamic acid D.

(Comparative Example 3)
A polyimide film was obtained in the same manner as in Example 1 except that SO1458 was not added.

(Comparative Example 4)
A polyimide film was obtained in the same manner as in Example 3 except that SO1458 was not added.

(Comparative Example 5)
A polyimide film was obtained in the same manner as in Comparative Example 1 except that SO1458 was not added.

(Comparative Example 6)
A polyimide film was obtained in the same manner as in Comparative Example 2 except that SO1458 was not added.

(Comparative Example 7)
A polyimide film was obtained in the same manner as in Example 1 except that SO1458 was changed to SO1450.

(Comparative Example 8)
A polyimide film was obtained in the same manner as in Example 1 except that SO1458 was changed to MS0840.

4). Measurement of various physical property values Table 1 shows the measurement results of thermal expansion coefficient, surface roughness (10-point average roughness (Rz)) and dielectric loss tangent of the polyimide films prepared in Examples and Comparative Examples. Moreover, the measuring method of these physical property values is shown below.

(1) Coefficient of thermal expansion Using a thermal analyzer (trade name “TMA50 series”, manufactured by Shimadzu Corporation), the coefficient of thermal expansion (ppm / K) of the polyimide film is measured in the range of 100 to 200 ° C. in a dry air atmosphere. It was measured.

(2) Surface roughness (10-point average roughness (Rz))
Using a stylus type surface shape measuring device (trade name “DEKTAK3”, manufactured by Nippon Vacuum Technology Co., Ltd.), the 10-point average roughness (Rz) of the polyimide film was measured. The measurement conditions were a measurement length of 2 mm, a measurement speed of 8 mm / min, and a high pass filter of 200 μm.

(3) Dielectric loss tangent The dielectric loss tangent (tan δ) of the polyimide film at a temperature of 23 ° C., a relative humidity of 60%, and a measurement frequency of 1 GHz was measured and calculated using the perturbation type cavity resonator method (measuring device: Vector Network Analyzer Anritsu 37225C). .

(A) an aromatic polyimide in which the total ratio of the aromatic diamine compound and the aromatic tetracarboxylic dianhydride to the total of the diamine compound and the tetracarboxylic dianhydride is 70 mol%; and (b) silanol. Examples 1 to 3, which are resin compositions comprising a cage-shaped silsesquioxane partially-cleavage structure having a phenyl group and a phenyl group, are (a) a polyimide film comprising only an aromatic polyimide (comparison) Compared to Examples 3 and 4), the dielectric loss tangent was low, and the absolute value thereof was particularly low.

  Also, Comparative Example 7 using a cage-shaped silsesquioxane partially-cleavage structure having an isobutyl group instead of a phenyl group, or a non-cleavable cage-shaped silsesquioxane having no silanol group was used. In Comparative Example 8, the result that the dielectric loss tangent was higher than that in Example 3 consisting of the same kind of (a) aromatic polyimide alone was obtained.

  Moreover, in the example (Examples 1-3 and Comparative Examples 1 and 2) containing the cage | basket-like silsesquioxane partial cleavage structure which has a silanol group and a phenyl group, when the said silsesquioxane is not included ( Compared with Comparative Examples 3 to 6), while the surface roughness is not substantially changed, Comparative Example 7 using a partially cleaved silsesquioxane structure having an isobutyl group and silanol In Comparative Example 8 using a non-cleavable cage-like silsesquioxane having no group, the surface roughness was rough. This is presumably because the silanol group and the phenyl group of the partially cleaved silsesquioxane structure having a silanol group and a phenyl group have high affinity for polyimide.

  In addition, the resin composition with low surface smoothness such as Comparative Examples 7 and 8 is likely to cause variations in dielectric characteristics and causes an increase in transmission loss when used as a circuit board. On the other hand, the resin compositions of Examples 1 to 3 having high surface smoothness and extremely low dielectric loss tangent are suitable for circuit boards and the like.

Since the resin composition of the present invention has a low dielectric loss tangent and high surface smoothness, it is suitable as a material for constituting various electronic circuit substrates, particularly high-frequency circuit substrates. The electronic circuit board of the present invention can be widely applied to various applications using high frequency such as a built-in antenna of a mobile phone, an antenna of an in-vehicle radar of an automobile, and a high-speed wireless communication for home use.

Claims (13)

(A) an aromatic polyimide obtained by reacting a diamine compound containing an aromatic diamine compound with a tetracarboxylic dianhydride containing an aromatic tetracarboxylic dianhydride,
The aromatic diamine compound or the aromatic tetracarboxylic dianhydride has only one aromatic ring or two or more aromatic rings connected by a single bond,
To the total of the tetracarboxylic dianhydride and the diamine compound, the total proportion of the said aromatic diamine compounds the aromatic tetracarboxylic acid dianhydride Ru der least 70 mol%, and an aromatic polyimide,
(B) a resin composition comprising a cage-shaped silsesquioxane partially-cleavage structure having a silanol group and a phenyl group,
Resin composition whose dielectric loss tangent is low compared with the dielectric loss tangent of said (a) aromatic polyimide. The aromatic diamine compound is a compound represented by the following general formula (A-1),
The resin composition according to claim 1, wherein the aromatic tetracarboxylic dianhydride is a compound represented by the following general formula (B).

(In general formula (A-1), n is an integer of 1 to 3.)

(In the general formula (B), X is a tetravalent aromatic group selected from phenyl, biphenyl, and triphenyl.)   The aromatic diamine compound contains p-phenylenediamine, the aromatic tetracarboxylic dianhydride contains pyromellitic dianhydride, the aromatic diamine compound and the aromatic tetracarboxylic dianhydride. The resin composition according to claim 1 or 2, wherein the ratio of the total of p-phenylenediamine and pyromellitic dianhydride to the total of the products is 50 mol% or more. The diamine compound other than the aromatic diamine compound contained in the diamine compound includes a compound having at least one site where two or more aromatic rings are bonded via one or more atoms in the molecule,
Tetracarboxylic dianhydrides other than the aromatic tetracarboxylic dianhydride contained in the tetracarboxylic dianhydride have two or more aromatic rings bonded through one or more atoms in the molecule. The resin composition as described in any one of Claims 1-3 containing the compound which has at least 1 or more site | parts.   The resin composition according to any one of claims 1 to 4, wherein a dielectric loss tangent at 1 GHz is 0.01 or less.   The resin composition according to any one of claims 1 to 5, wherein, when formed into a film, the 10-point average roughness (Rz) at the air interface is 1 µm or less.   The resin composition according to any one of claims 1 to 6, wherein, when formed into a film, the coefficient of thermal expansion at 100 to 200 ° C is 25 ppm / ° C or less. The partially-branched silsesquioxane structure (b) having a silanol group and a phenyl group is a compound represented by the following general formula (1-a). The resin composition described in 1.

  The resin composition according to any one of claims 1 to 8, further comprising a flame retardant.   The polyimide metal laminated body provided with the insulating layer which consists of a resin composition as described in any one of Claims 1-9, and the metal layer arrange | positioned on the at least one surface of the said insulating layer.   The board | substrate for electronic circuits provided with the polyimide metal laminated body of Claim 10.   The electronic circuit board according to claim 11, wherein the insulating layer is a flexible circuit board having a thickness of 50 μm or less. (A) an aromatic polyamic acid obtained by reacting a diamine compound containing an aromatic diamine compound with a tetracarboxylic dianhydride containing an aromatic tetracarboxylic dianhydride,
The aromatic diamine compound or the aromatic tetracarboxylic dianhydride has only one aromatic ring or two or more aromatic rings connected by a single bond,
An aromatic polyamic acid, wherein the ratio of the total of the aromatic diamine compound and the aromatic tetracarboxylic dianhydride to the total of the diamine compound and the tetracarboxylic dianhydride is 70 mol% or more;
(B) a cage-shaped silsesquioxane partially-cleavage structure having a silanol group and a phenyl group;
Obtaining a mixture of
Heating the mixture to a temperature at which the imidization of the aromatic polyamic acid proceeds to a temperature or higher.