JP4768606B2 - Laminate for wiring board - Google Patents

Description

  The present invention is a laminate for a wiring board used for flexible printed wiring boards, HDD suspensions and the like.

  In recent years, high performance, high functionality, and miniaturization of electronic devices have been rapidly progressing, and accordingly, electronic components used in electronic devices and substrates on which they are mounted have higher density and higher performance. The demand for things is increasing. With regard to flexible printed wiring boards (hereinafter referred to as FPC), fine wire processing, multilayer formation, etc. have been carried out, and thinning and dimensional stability have also been strictly demanded for the materials constituting FPC. .

  In general, films made of polyimide resin with excellent properties are widely used for FPC insulation film, and epoxy resin and acrylic resin with excellent low-temperature workability are used for the insulating adhesive layer between the insulation film and metal. It has been. However, these adhesive layers have a problem of causing a decrease in heat resistance and thermal dimensional stability.

  In order to solve such problems, recently, a method in which a polyimide resin layer is directly formed on a metal without forming an adhesive layer has been adopted. Japanese Examined Patent Publication No. 6-93537 discloses a method of providing an FPC having excellent adhesion and thermal dimensional stability by multilayering a polyimide resin layer with a plurality of polyimides having different thermal expansion coefficients. . However, these polyimides have a high hygroscopic property, so problems such as swelling when immersed in a solder bath and poor connection due to dimensional changes after moisture absorption during thin wire processing are induced. Since the expansion coefficient was 0 or close to 0, the dimensional change after moisture absorption was a cause of problems such as warpage, curl, and twist of the laminate.

Prior literature relating to the present invention includes the following literature.
Japanese Patent Publication No. 6-93537 JP-A-2-225522 JP 2001-11177 A JP-A-5-271410

  Against this background, in recent years, there has been an increasing demand for FPC made of a polyimide resin having excellent low hygroscopicity and dimensional stability after moisture absorption, and various studies for improving the polyimide used therefor have been made. For example, in Japanese Patent Application Laid-Open No. 2-225522 and Japanese Patent Application Laid-Open No. 2001-11177, a polyimide that improves hydrophobicity and exhibits low hygroscopicity by introducing a fluorine-based resin is proposed. There is a disadvantage that it is covered and has poor adhesion to metal materials. As for other efforts to reduce moisture absorption, as shown in Japanese Patent Application Laid-Open No. 5-271410, etc., it achieves low moisture absorption while maintaining good characteristics such as high heat resistance and low thermal expansion coefficient. It wasn't.

  Polyimide has a structure in which dicarboxylic acid components and diamine components are alternately bonded. Polyimide using diaminobiphenyl or diaminobiphenyl substituted with methoxy as the diamine is disclosed in JP-A-2001-11177 and Although exemplified in Japanese Patent Application Laid-Open No. 5-271410, specific examples thereof are not shown, and it is impossible to predict what characteristics they have.

  Therefore, the present invention has been made to solve the above problems, and to provide a laminate for a wiring board having a polyimide layer that has excellent heat resistance, thermal dimensional stability, and realizes low moisture absorption. To do.

（式中、Ａｒ₁はピロメリット酸二無水物、ナフタレン−2,3,6,7−テトラカルボン酸二無水物又は3,3',4,4'−ビフェニルテトラカルボン酸二無水物から生じる4価の有機基であり、Rは炭素数３〜６の炭化水素基である。） The present invention provides a laminate having a metal foil on one or both sides of a polyimide resin layer, wherein the polyimide resin layer is composed of only a polyimide resin, and at least one layer contains 10 mol of a structural unit represented by the following general formula (1). %, And the polyimide resin layer has a linear expansion coefficient of 30 ppm / ° C. or less and a humidity expansion coefficient of 10 ppm /% RH or less.

(Wherein Ar ₁ is derived from pyromellitic dianhydride, naphthalene-2,3,6,7-tetracarboxylic dianhydride or 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride. (It is a tetravalent organic group, and R is a hydrocarbon group having 3 to 6 carbon atoms.)

  The laminate for a wiring board of the present invention has a structure in which a metal foil is laminated on one side or both sides of a single-layer or multilayer polyimide resin layer. At least one of the polyimide resin layers contains 10 mol% or more of the structural unit represented by the general formula (1).

In the structural unit represented by the general formula (1), Ar ₁ is a tetravalent organic group having one or more aromatic rings, and is an aromatic produced from an aromatic tetracarboxylic acid or an acid dianhydride thereof. It can be called a tetracarboxylic acid residue. Therefore, Ar ₁ is understood by describing the aromatic tetracarboxylic acid used. Usually, when synthesizing a polyimide having the above structural unit, an aromatic tetracarboxylic dianhydride is often used, so preferable Ar ₁ is described below using an aromatic tetracarboxylic dianhydride. .

  It does not specifically limit as said aromatic tetracarboxylic dianhydride, A well-known thing can be used. Specific examples include pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 2,2 ′, 3,3′-benzophenone tetracarboxylic dianhydride, 2 , 3,3 ', 4'-benzophenonetetracarboxylic dianhydride, naphthalene-2,3,6,7-tetracarboxylic dianhydride, naphthalene-1,2,5,6-tetracarboxylic dianhydride , Naphthalene-1,2,4,5-tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, naphthalene-1,2,6,7-tetracarboxylic dianhydride 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3 , 5,6,7-hexahydronaphthalene-2,3,6,7-tetracarboxylic dianhydride, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2, 7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3,6,7-tetrachloronaphth Len-1,4,5,8-tetracarboxylic dianhydride, 1,4,5,8-tetrachloronaphthalene-2,3,6,7-tetracarboxylic dianhydride, 3,3 ', 4 , 4'-biphenyltetracarboxylic dianhydride, 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride, 2,3,3', 4'-biphenyltetracarboxylic dianhydride, 3, 3 '', 4,4 ''-p-terphenyltetracarboxylic dianhydride, 2,2``, 3,3 ''-p-terphenyltetracarboxylic dianhydride, 2,3,3 ' ', 4' '-p-terphenyltetracarboxylic dianhydride, 2,2-bis (2,3-dicarboxyphenyl) -propane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) ) -Propane dianhydride, bis (2,3-dicarboxyphenyl) ether dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, bis (3.4-dicarboxyphenyl) methane dianhydride, Bis (2,3-dicarboxyphenyl) sulfone dianhydride, bis (3,4-dicarboxyphenyl) Enyl) sulfone dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, perylene-2,3 , 8,9-tetracarboxylic dianhydride, perylene-3,4,9,10-tetracarboxylic dianhydride, perylene-4,5,10,11-tetracarboxylic dianhydride, perylene-5, 6,11,12-tetracarboxylic dianhydride, phenanthrene-1,2,7,8-tetracarboxylic dianhydride, phenanthrene-1,2,6,7-tetracarboxylic dianhydride, phenanthrene-1 , 2,9,10-Tetracarboxylic dianhydride, cyclopentane-1,2,3,4-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, pyrrolidine -2,3,4,5-tetracarboxylic dianhydride, thiophene-2,3,4,5-tetracarboxylic dianhydride, 4,4'-oxydiphthalic dianhydride, and the like. Moreover, these can be used individually or in mixture of 2 or more types.

  Among these, pyromellitic dianhydride (PMDA), naphthalene-2,3,6,7-tetracarboxylic dianhydride (NTCDA) and 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride Preferred is one selected from products (BPDA). In particular, in order to realize a low thermal expansion coefficient, it is preferable to use PMDA or NTCDA. By mixing and using an appropriate amount of BPDA, the coefficient of thermal expansion can be adjusted to the same level as metal foil, and it can be adjusted to a practically required value of 20 ppm / ° C or less. is there. Thereby, it is possible to suppress the occurrence of warping, curling, and the like of the laminated body. These aromatic tetracarboxylic dianhydrides can be used in combination with other aromatic tetracarboxylic dianhydrides, but may be used in an amount of 50 mol% or more, preferably 70 mol% or more. good. That is, in selecting tetracarboxylic dianhydride, specifically, it is suitable for expressing the properties required for the purpose of use, such as the thermal expansion coefficient, thermal decomposition temperature, and glass transition temperature of polyimide obtained by polymerization and heating. It is preferable to select one.

The diamine used as an essential component in the synthesis of the polyimide resin used in the present invention is an aromatic diamine represented by the following general formula (2).

  Here, R has the same meaning as R in the general formula (1) and is a hydrocarbon group having 1 to 6 carbon atoms, preferably an alkyl group having 1 to 4 or an aryl group having 6 carbon atoms. More preferred are an ethyl group, an n-propyl group, and a phenyl group.

  The polyimide resin used in the present invention is preferably obtained by reacting an aromatic tetracarboxylic dianhydride with a diamine containing 10 mol% or more of the aromatic diamine represented by the general formula (2). it can.

  In the present invention, in addition to the aromatic diamine represented by the general formula (2), other diamines other than the aromatic diamine can be used in a proportion of 90 mol% or less. can do.

  The structural unit represented by the general formula (1) is 10 to 100 mol%, preferably 50 to 100 mol%, more preferably 70 to 100 mol%, still more preferably 90 to 100 mol% in at least one layer of the polyimide resin layer. % Should be included.

  The diamine other than the aromatic diamine represented by the general formula (2) is not particularly limited, but examples include 4,6-dimethyl-m-phenylenediamine and 2,5-dimethyl. -p-phenylenediamine, 2,4-diaminomesitylene, 4,4'-methylenedi-o-toluidine, 4,4'-methylenedi-2,6-xylidine, 4,4'-methylene-2,6-diethylaniline 2,4-toluenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylpropane, 3,3'-diaminodiphenylpropane, 4,4'-diaminodiphenylethane, 3,3'- Diaminodiphenylethane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane 4,4'-diaminodiphenyl sulfide, 3,3 ' -Diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfo 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 3,3-diaminodiphenyl ether, 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene 1,4-bis (4-aminophenoxy) benzene, benzidine, 3,3'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxybenzidine, 4,4 '-Diamino-p-terphenyl, 3,3'-diamino-p-terphenyl, bis (p-aminocyclohexyl) methane, bis (p-β-amino-t-butylphenyl) ether, bis (p-β -Methyl-δ-aminopentyl) benzene, p-bis (2-methyl-4-aminopentyl) benzene, p-bis (1,1-dimethyl-5-aminopentyl) benzene, 1,5-diaminonaphthalene, 2 , 6-Diaminonaphthalene, 2,4-bis (β-amino-t-butyl) toluene, 2,4-diaminotoluene, m-xy Len-2,5-diamine, p-xylene-2,5-diamine, m-xylylenediamine, p-xylylenediamine, 2,6-diaminopyridine, 2,5-diaminopyridine, 2,5-diamino- 1,3,4-oxadiazole, piperazine, 3,4,4'-triaminophenyl ether, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-bis (4-aminophenoxy ) Biphenyl and the like.

  Among these, 4,4'-diaminodiphenyl ether (DAPE), 1,3-bis (4-aminophenoxy) benzene (TPE-R), p-phenyldiamine (p-PDA), 2,2'-dimethyl- 4,4′-diaminobiphenyl (m-TB) and the like are preferably used. Moreover, when using these diamines, the preferable usage rate is the range of 0-50 mol% of all the diamine, More preferably, it is the range of 0-30 mol%.

  The polyamic acid used as the precursor of the polyimide resin is a known polymerized polymer in an organic polar solvent using the aromatic diamine component and the aromatic tetracarboxylic dianhydride component shown above in a molar ratio of 0.9 to 1.1. It can be manufactured by a method. That is, after dissolving an aromatic diamine in an organic solvent such as N, N-dimethylacetamide and N-methyl-2-pyrrolidone under a nitrogen stream, an aromatic tetracarboxylic dianhydride is added, and the mixture is added at room temperature for 3-4. It is obtained by reacting for about an hour. At this time, the molecular terminal may be sealed with an aromatic monoamine or dicarboxylic anhydride.

  When using an aromatic tetracarboxylic dianhydride component containing a naphthalene skeleton, for example, after dissolving the aromatic diamine component in m-cresol under a nitrogen stream, the catalyst and the aromatic tetracarboxylic dianhydride component are added. In addition, it can be obtained by heating at about 190 ° C. for about 10 hours and then reacting for about 8 hours after returning to room temperature.

  The polyamic acid solution obtained by the above reaction is applied onto a metal foil serving as a support or an adhesive layer formed on the metal foil using an applicator, and imide is obtained by a thermal imidization method or a chemical imidization method. The laminated body for a wiring board of the present invention is obtained. Thermal imidization is performed by pre-drying at a temperature of 150 ° C. or lower for 2 to 60 minutes and then heat-treating at a temperature of about 130 to 360 ° C. for about 2 to 30 minutes. Chemical imidization is performed by adding a dehydrating agent and a catalyst to polyamic acid. The metal foil used is preferably a copper foil or a SUS foil, and its preferred thickness range is also 50 μm or less, advantageously 5 to 40 μm. A thinner copper foil is suitable for forming a fine pattern. From such a viewpoint, a range of 8 to 15 μm is preferable.

  The polyimide resin layer may be a single layer or a multilayer. In the case of a multilayer polyimide resin layer, after repeating the operation of applying and drying a polyamic acid solution, the solvent is removed by heat treatment, and this is further heat treated at a high temperature to imidize to obtain a polyimide structure having a multilayer structure. A resin layer can be formed. At this time, the total thickness of the formed polyimide resin layer is preferably in the range of 3 to 75 μm. In the case of a multilayer, at least one of the layers must be a polyimide resin layer (hereinafter also referred to as the present polyimide resin layer) containing 10 mol% or more of the structural unit represented by the general formula (1), and its thickness Is 30% or more of the entire polyimide resin layer, preferably 50% or more.

Moreover, when manufacturing the laminated body for wiring boards which has metal foil on both surfaces, after forming a metal foil directly or after forming an adhesive layer on the polyimide resin layer of the laminated body for single-sided wiring boards obtained by the said method, It is obtained by thermocompression bonding. The hot pressing temperature at the time of the thermocompression bonding is not particularly limited, but it is desirable to be not lower than the glass transition temperature of the polyimide resin used. The hot press pressure is preferably in the range of 1 to 500 kg / cm ² , although it depends on the type of press equipment used. Furthermore, the preferable metal foil used at this time can use the thing similar to the above-mentioned metal foil, The preferable thickness is also 50 micrometers or less, More preferably, it is the range of 5-40 micrometers.

  The polyimide resin layer constituting the laminate for a wiring board of the present invention comprises an aromatic diamine represented by the general formula (2) and other aromatic diamines and aromatic tetracarboxylic acids used in combination with the aromatic diamines. Properties can be controlled by various combinations with acid dianhydrides. A preferred polyimide resin layer has a linear expansion coefficient of 30 ppm / ° C. or less, a storage elastic modulus at 23 ° C. of 6 GPa or less, and a moisture absorption rate of 0.8 wt% or less. From the viewpoint of heat resistance, the glass transition temperature is 350 ° C or higher, and 5% weight loss temperature (Td5%) in thermogravimetric analysis should be in the range of 500-600 ° C. Furthermore, humidity expansion coefficient is 10ppm /% RH in both TD and MD directions. The following are good. The 5% weight loss temperature is also referred to as the thermal decomposition temperature.

  EXAMPLES Hereinafter, although the content of this invention is demonstrated concretely based on an Example, this invention is not limited to the range of these Examples.

Abbreviations used in Examples and the like are shown below.
-PMDA: pyromellitic dianhydride-BPDA: 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride-m-MOB: 2,2'-dimethoxybenzidine-m-EOB: 2,2' -Diethoxybenzidine, m-POB: 2,2'-di-n-propyloxybenzidine, m-PHOB: 2,2'-diphenyloxybenzidine, DAPE: 4,4'-diaminodiphenyl ether, m-TB: 2 , 2'-dimethylbenzidine, TPE-R: 1,3-bis (4-aminophenoxy) benzene, BAPP: 2,2-bis (4-aminophenoxyphenyl) propane, DMAc: N, N-dimethylacetamide

In addition, measurement methods and conditions for various physical properties in the examples are shown below.
[Glass transition temperature (Tg), storage elastic modulus (E ')]
The dynamic viscoelasticity was measured when the polyimide film (10mm × 22.6mm) obtained in each example was heated from 20 ° C to 500 ° C at 5 ° C / min with a dynamic thermomechanical analysis (DMA) device. The glass transition temperature (tan δ maximum value) and the storage elastic modulus (E ′ ₂₃ and E ′ ₁₀₀ ) at 23 ° C. and 100 ° C. were determined.

[Measurement of linear expansion coefficient (CTE)]
A tensile test was performed on a polyimide film having a size of 3 mm × 15 mm in a temperature range from 30 ° C. to 260 ° C. at a constant temperature increase rate while applying a 5.0 g load with a thermomechanical analysis (TMA) apparatus. The linear expansion coefficient was determined from the amount of elongation of the polyimide film with respect to temperature.

[Measurement of thermal decomposition temperature (Td5%)]
Measure the change in weight of a 10-20 mg polyimide film when heated from 30 ° C to 550 ° C at a constant rate using a thermogravimetric analysis (TG) device to obtain a 5% weight loss temperature (Td5%). It was.

[Measurement of moisture absorption rate (RMA)]
4cm x 20cm polyimide films (3 sheets each) are dried at 120 ° C for 2 hours, then left in a constant temperature and humidity chamber at 23 ° C / 50% RH for 24 hours or more. Asked.
RMA (%) = [(weight after moisture absorption-weight after drying) / weight after drying] × 100

[Measurement of humidity expansion coefficient (CHE)]
An etching resist layer was provided on a copper foil of a polyimide / copper foil laminate of 35 cm × 35 cm, and this was formed into a pattern in which 12 points with a diameter of 1 mm were arranged at 10 cm intervals on four sides of a 30 cm square. The exposed portion of the copper foil in the opening portion of the etching resist was etched to obtain a polyimide film for CHE measurement having 12 copper foil remaining points. After drying this film at 120 ° C for 2 hours, leave it at 23 ° C / 50% RH constant temperature and humidity chamber for more than 24 hours, and measure the dimensional change (0-50% RH) between the copper foil points with a two-dimensional measuring machine. ) Was measured to determine the humidity expansion coefficient.

Synthesis Examples 1-18
Polyamic acid used in Examples and Comparative Examples was synthesized.
Under a nitrogen stream, the diamine shown in Table 1 was dissolved in 43 g of solvent DMAc with stirring in a 100 ml separable flask. Subsequently, the tetracarboxylic dianhydride shown in Table 1 was added. Thereafter, the solution was stirred at room temperature for 3 to 4 hours to carry out a polymerization reaction to obtain a yellow-brown viscous solution of 18 kinds of polyamic acids (PA) A to R to be polyimide precursors. The reduced viscosity (η _sp / C) of each polyamic acid solution was in the range of 3-6. The weight average molecular weight Mw is shown in Table 1.

Example 1
Before applying the solutions of polyamic acids (PA) A to R obtained in Synthesis Examples 1 to 18, DMAc was added to adjust the viscosity to about 250 pois. Then, using an applicator on each 35 μm thick copper foil, the film thickness after drying is about 15 μm, dried at 50 to 130 ° C. for 2 to 60 minutes, then further 130 ° C., 160 Stepwise heat treatment was performed at 2 ° C. for 2 to 30 minutes at 200 ° C., 200 ° C., 230 ° C., 280 ° C., 320 ° C. and 360 ° C., and a polyimide layer was formed on the copper foil to obtain 18 kinds of laminates. The laminate obtained from the polyamic acid A solution obtained in Synthesis Example 1 is designated as laminate A, and so on. The laminate J obtained using the polyamic acid J solution obtained in Synthesis Example 10 is a comparative example. Further, the laminate R obtained by using the solution of the polyamic acid R obtained in Synthesis Example 18 is for evaluating the characteristics of one polyimide layer of the laminates M1 to M3 in Examples described later.

For the laminates A to R of Example 1, the copper foil was etched away using an aqueous ferric chloride solution to create 18 types of polyimide films, glass transition temperature (Tg), storage elastic modulus (E ′), The coefficient of thermal expansion (CTE), 5% weight loss temperature (Td5%), moisture absorption rate (RMA), and humidity expansion coefficient (CHE) were measured.
Table 2 shows the measurement results.

Example 2
The solution of polyamic acid R prepared in Synthesis Example 18 was uniformly applied to a thickness of 25 μm on a copper foil having a thickness of 18 μm, and then dried by heating at 130 ° C. to remove the solvent. Next, the polyamic acid E solution prepared in Synthesis Example 5 was uniformly applied to a thickness of 195 μm so as to be laminated thereon, and dried by heating at 70 ° C. to 130 ° C. to remove the solvent. Further, the polyamic acid R solution prepared in Synthesis Example 18 was uniformly applied on the polyamic acid E layer in a thickness of 37 μm, and dried by heating at 135 ° C. to remove the solvent. Thereafter, heat treatment was performed from room temperature to 360 ° C. for about 5 hours to imidize, and thus a laminate M1 in which an insulating resin layer composed of three polyimide resin layers and having a total thickness of about 25 μm was formed on a copper foil was obtained. The thickness of the polyamic acid resin layer applied on the copper foil after drying is about 2.5 μm / about 19 μm / about 3.5 μm in the order of R / E / R.

Examples 3-4
In the same manner as in Example 2, laminates M2 and M3 in which an insulating resin layer having a total thickness of about 25 μm composed of three polyimide resin layers was formed on a copper foil were obtained. The type of polyamic acid solution applied on the copper foil and the thickness after drying are, in order, M2 about R 2.5μm / O about 19μm / R about 3.5μm, M3 about R about 2.5μm / Q about 19μm / R about 3.5 μm.

The adhesive strength of the laminates M1 to M3 obtained in Examples 2 to 4 was measured. Moreover, the copper foil was etched away using a ferric chloride aqueous solution to prepare a polyimide film, and the thermal expansion coefficient (CTE) of the three polyimide layers was measured.
Table 3 shows the measurement results.

  In the laminate for a wiring board of the present invention, the polyimide resin layer serving as an insulating layer has excellent heat resistance, low moisture absorption, and excellent dimensional stability, and is free from warping due to humidity without causing problems due to the adhesive layer. It also has an inhibitory effect. In addition, the polyimide resin layer of the insulating layer has a feature that there is no in-plane anisotropy because the difference in humidity expansion coefficient between the TD direction and the MD direction is small, and it is widely applied to parts in the electronic material field be able to. It is particularly useful for applications such as FPC and HDD suspension substrates.

Claims (6)

In a laminate having a metal foil on one or both sides of a polyimide resin layer, the polyimide resin layer is composed of only a polyimide resin, and at least one layer contains 10 mol% or more of a structural unit represented by the following general formula (1). A laminate for a flexible wiring board, wherein the polyimide resin layer has a linear expansion coefficient of 30 ppm / ° C. or less and a humidity expansion coefficient of 10 ppm /% RH or less.

Where Ar ₁ is derived from pyromellitic dianhydride, naphthalene-2,3,6,7-tetracarboxylic dianhydride or 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride 4 R is a hydrocarbon group having 3 to 6 carbon atoms.   The laminate for a wiring board according to claim 1, wherein the polyimide resin layer has a storage elastic modulus at 23 ° C of 6 GPa or less and a moisture absorption of 0.8 wt% or less.   The laminate for a wiring board according to claim 1, wherein the polyimide resin layer has a 5% weight reduction temperature (Td 5%) in a range of 500 to 600 ° C. in thermogravimetric analysis.   The laminate for a wiring board according to any one of claims 1 to 3, wherein the polyimide resin layer comprises one layer. In General formula (1), R is a propyl group or a phenyl group, The laminated body for wiring boards in any one of Claims 1-3.   The laminate for a wiring board according to claim 1, wherein at least one of the polyimide resin layers contains 50 to 100 mol% of a structural unit represented by the general formula (1).