TW202316920A - Metal-clad laminate, circuit substrate, electronic device and electronic apparatus - Google Patents

Abstract

The subject of the present invention is to achieve both the suppression of wrinkles when metal foil is hot-pressed onto a single-sided metal clad laminate at high temperatures and the interfacial tightness between the hot-pressed metal foil and the polyimide layer. The metal-clad laminate (100) comprises: a first metal layer (101) and an insulating resin layer (110) laminated on the first metal layer (101). The insulating resin layer (110) has a polyimide layer (A) in contact with the first metal layer (101), and a polyimide layer (B) forming a resin surface on the side opposite to the first metal layer (101). Based on the glass transition temperature Tg of the polyimide layer (B), the storage elastic modulus of the polyimide layer (A) at any temperature within the range from Tg+20 DEG C to Tg+90 DEG C is set to be E'(A) and the storage elastic modulus of the polyimide layer (B) is set to be E'(B), the ratio of storage elastic modulus E'(A)/E'(B) is 2.0 or more.

Description

Metal-clad laminates, circuit substrates, electronic components and electronic equipment

The present invention relates to a metal-clad laminate, a circuit substrate obtained by performing circuit processing thereon, electronic components and electronic equipment using the circuit substrate.

In recent years, with the advancement of miniaturization, weight reduction, and space saving of electronic equipment, flexible printed wiring boards (Flexible Printed Circuits, FPC) that are thin, lightweight, flexible, and have excellent durability even after repeated bending Need to increase. FPC can achieve three-dimensional and high-density installation even in a limited space, so it is used in movable parts of electronic devices such as hard disk drives (HDD), digital video disks (DVD), and smartphones. Its use in wiring or cables, connectors and other parts is gradually expanding.

Typically, an FPC is manufactured by etching a metal layer of a metal-clad laminate (copper clad laminate (CCL) or the like), which is a material, and performing wiring processing. As for metal-clad laminates, laminates using polyimide with a high storage elastic modulus for an insulating resin layer in contact with a metal foil have been proposed (for example, Patent Document 1 and Patent Document 2).

In a single-sided metal-clad laminate including a metal layer on one side of a polyimide layer as an insulating resin layer, thermoplastic polyimide is generally widely used for the polyimide layer in contact with the metal layer. Specifically, a laminated structure of thermoplastic polyimide layer/non-thermoplastic polyimide layer/thermoplastic polyimide layer is often adopted from the metal layer side of the single-sided metal-clad laminate. In the case of producing a double-sided metal-clad laminate by thermocompression-bonding metal foil to the outermost thermoplastic polyimide layer of a single-sided metal-clad laminate with such a structure, in order to ensure that the outermost thermoplastic polyimide To obtain sufficient peel strength between the laminated layer and the metal foil, it is necessary to perform thermocompression bonding at a high temperature of about 200°C to 400°C. However, if thermocompression bonding is performed at a high temperature, the thermoplastic polyimide layer on the side of the single-sided metal-clad laminate that is in contact with the metal layer softens, causing wrinkles to easily form on the adjacent metal layer. The problem can be solved by lowering the thermocompression bonding temperature to suppress the softening of the thermoplastic polyimide layer, but in this case, the adhesion between the thermoplastic polyimide layer on the side of the laminate layer and the thermocompression-bonded metal foil becomes poor. Insufficient, the adhesion reliability after wiring processing cannot be ensured. [Prior art literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2020-104340 [Patent Document 2] Japanese Patent Laid-Open No. 2006-051800

[Problem to be Solved by the Invention] The object of the present invention is to realize the coexistence of suppression of wrinkles when a metal foil is thermocompression-bonded to a single-sided metal-clad laminate at high temperature, and interface adhesion between the thermocompression-bonded metal foil and a polyimide layer. [Technical means to solve the problem]

The inventors of the present invention conducted diligent research and found that the storage elastic modulus of the thermoplastic polyimide layer in contact with the metal layer of the single-sided metal-clad laminate is larger than that of the thermoplastic polyimide layer on the side of the laminated layer. The storage modulus of elasticity can solve the problem, thus completing the present invention.

That is, the metal-clad laminate of the present invention includes: the first metal layer; and An insulating resin layer is laminated on the first metal layer, and the metal-clad laminate is characterized in that, The insulating resin layer has a polyimide layer (A) in contact with the first metal layer, and a polyimide layer (B) having a resin surface formed on a side opposite to the first metal layer. ), When taking the glass transition temperature Tg of the polyimide layer (B) as a reference, the temperature of the polyimide layer (A) at any temperature within the range from Tg+20°C to Tg+90°C When the storage elastic modulus is E'(A) and the storage elastic modulus of the polyimide layer (B) is E'(B), the ratio of the storage elastic modulus E'(A)/E '(B) is 2.0 or more.

In the metal-clad laminate of the present invention, the insulating resin layer may have a polyimide layer (C) laminated between the polyimide layer (A) and the polyimide layer (B). .

In the metal-clad laminate of the present invention, the thickness of the first metal layer may be in the range of 6 μm to 18 μm, and the tensile modulus of elasticity may be in the range of 10 GPa to 100 GPa.

The metal-clad laminate of the present invention may further include a second metal layer laminated in contact with the resin surface of the polyimide layer (B).

In the metal-clad laminate of the present invention, the peel strength between the second metal layer and the polyimide layer (B) may be 0.7 kN/m or more.

The circuit board of the present invention is obtained by performing circuit processing on either or both of the first metal layer and the second metal layer in the metal-clad laminate.

The circuit board of the present invention is a circuit board obtained by performing circuit processing on the first metal layer in the metal-clad laminate.

An electronic component of the present invention may include the circuit substrate.

An electronic device of the present invention may include the circuit substrate. [Effect of the invention]

In the metal-clad laminate of the present invention, the storage elastic modulus E'(A) of the polyimide layer (A) in contact with the first metal layer and the storage modulus E'(A) of the polyimide layer (B) on the side of the laminated layer The ratio E'(A)/E'(B) of the modulus of elasticity E'(B) is 2.0 or more, thereby preventing the first metal layer from generation of wrinkles. Therefore, it is possible to achieve both the interface adhesion between the thermocompression-bonded metal foil and the polyimide layer and the suppression of wrinkles of the first metal layer when the metal foil is thermocompression-bonded to the metal-clad laminate at high temperature. Therefore, by using the metal-clad laminate of the present invention as an FPC material, the reliability and yield of the circuit board can be improved.

Next, embodiments of the present invention will be described with reference to the drawings as appropriate.

<First Embodiment and Second Embodiment> As shown in FIG. 1 , the metal-clad laminate 100 according to the first embodiment of the present invention includes a first metal layer 101 and an insulating resin layer 110 laminated on the first metal layer 101 . The metal-clad laminate 100 is a single-sided metal-clad laminate. In addition, as shown in FIG. 2 , the metal-clad laminate 200 according to the second embodiment of the present invention includes a first metal layer 101 , an insulating resin layer 110 laminated on the first metal layer 101 , and an insulating resin layer laminated on the insulating resin layer 110 . The first metal layer 101 is the second metal layer 102 on the opposite side. The metal-clad laminate 200 is a double-sided metal-clad laminate.

<Insulating resin layer> The insulating resin layer 110 includes a polyimide layer (A) in contact with the first metal layer 101 , and a polyimide layer (A) having a resin surface formed on the side opposite to the first metal layer 101 . B), and the polyimide layer (C) laminated between the polyimide layer (A) and the polyimide layer (B). The polyimide layer (A) is a thermoplastic polyimide layer obtained by applying a polyamic acid solution to the first metal layer 101 by casting method, drying and imidizing, and has the same A metal layer 101 contacts the polyimide layer of the casting surface. The polyimide layer (B) is a thermoplastic polyimide layer having a build-up layer 110 a for thermocompression-bonding metal foil or the like as the second metal layer 102 . The polyimide layer (C) plays a role of maintaining the mechanical strength of the insulating resin layer 110 as a base resin layer. In the present invention, polyimides having different storage elastic moduli are used for the polyimide layer (A) and the polyimide layer (B) forming the insulating resin layer 110 . Here, the so-called non-thermoplastic polyimide generally refers to a polyimide that does not show softening or adhesiveness even when heated, but in the present invention, it refers to a polyimide that uses a dynamic viscoelasticity measuring device (dynamic thermomechanical A polyamide having a storage elastic modulus of 1.0×10 ⁹ Pa or higher at 30°C measured by a dynamic thermomechanical analyzer (DMA) and a storage elastic modulus of 3.0×10 ⁸ Pa or higher at 320°C amine. In addition, thermoplastic polyimide generally refers to a polyimide whose glass transition temperature (Tg) can be clearly confirmed, but in the present invention, it means that the storage elastic modulus at 30°C measured using DMA is A polyimide that is 1.0×10 ⁹ Pa or more and has a storage elastic modulus at 320° C. of less than 3.0×10 ⁸ Pa.

In addition, the insulating resin layer 110 may include any resin layer other than the polyimide layer (A) to the polyimide layer (C) within the range that does not impair the effect of the invention.

With regard to the insulating resin layer 110, when the polyimide layer (B) at any temperature within the range from Tg+20°C to Tg+90°C is based on the glass transition temperature Tg of the polyimide layer (B), When the storage elastic modulus of (A) is E'(A), and the storage elastic modulus of the polyimide layer (B) is E'(B), the ratio of the storage elastic modulus E'( A)/E'(B) is 2.0 or more. When the metal foil as the second metal layer 102 is thermocompression-bonded to the build-up layer 110a on the side of the polyimide layer (B) at high temperature, the storage elastic modulus E'(B) of the polyimide layer (B) The smaller it is, the better the polyimide can fill the fine unevenness of the metal foil during thermocompression bonding, and the higher the adhesion reliability will be. In addition, tension will be applied during thermocompression bonding, but the storage elastic modulus E'(A) of the polyimide layer (A) is larger. When thermocompression bonding at high temperature, the first metal as a support The polyimide layer (A) that is in contact with the layer 101 is less likely to be softened, and the occurrence of wrinkles in the first metal layer 101 can be suppressed. Therefore, by setting the ratio E'(A)/E'(B) to 2.0 or more, for example, in the range of 200°C to 400°C, especially in the range of 270°C to 400°C, and furthermore in the range of 320°C to 400°C When thermocompression bonding is performed at a high temperature in the range of °C, both the adhesion at the build-up layer 110 a and the suppression of wrinkles of the first metal layer 101 can be achieved. From such a viewpoint, the ratio E'(A)/E'(B) is preferably 3-100, more preferably 5-60, and most preferably 10-40.

In the present invention, the ratio E'(A)/E'(B) should be within the range of Tg+20°C to Tg+90°C relative to the glass transition temperature Tg of the polyimide layer (B). It is sufficient to satisfy the above-mentioned regulation at any temperature, and it is preferable to satisfy the above-mentioned regulation at all temperatures in the range from Tg+20°C to Tg+90°C. Here, the storage elastic modulus of the polyimide layer (B) at any temperature in the range from the glass transition temperature Tg+20°C to Tg+90°C was compared for the following reasons . That is, at the glass transition temperature Tg of the polyimide layer (B), the polyimide layer (B) does not soften, so the temperature range until the polyimide layer (B) is fully softened is estimated, and Tg+20°C is set as the lower limit , On the other hand, Tg+90°C is set as the upper limit so that the practical thermocompression bonding temperature can be covered even when the Tg of the polyimide layer (B) is low.

The glass transition temperature Tg of the polyimide layer (A) is not particularly limited as long as the effect of the invention can be obtained, but in order to ensure the adhesion with the first metal layer 101, it is preferably 200°C or higher and 400°C or lower. range, more preferably in the range of 250°C or more and 380°C or less. In addition, the storage elastic modulus E'(A) of the polyimide layer (A) is not particularly limited as long as the effect of the invention can be obtained, but a relatively high storage elastic modulus E'(A) is not suitable for thermocompression bonding. In this case, the suppression of wrinkles of the first metal layer 101 is effective, and it is preferably in the range of 1×10 ⁷ Pa to 1×10 ¹⁰ Pa, more preferably in the range of 1×10 ⁸ Pa to 1×10 ¹⁰ Pa.

The glass transition temperature Tg of the polyimide layer (B) is not particularly limited as long as the effect of the invention can be obtained, but in order to ensure the adhesion with the second metal layer 102, it is preferably 200°C or higher and 400°C or lower. range, more preferably in the range of 200°C or higher and 350°C or lower. In addition, the storage elastic modulus E'(B) of the polyimide layer (B) is not particularly limited as long as the effect of the invention can be obtained, but a relatively low storage elastic modulus E'(B) improves the adhesiveness. It is advantageous, but if it is too low, thermocompression bonding becomes difficult, so it is preferably in the range of 1×10 ⁵ Pa to 1×10 ⁸ Pa, more preferably in the range of 1×10 ⁶ Pa to 9×10 ⁷ Pa Inside is better.

In addition, Tg and storage elastic modulus of each polyimide layer were measured using a dynamic viscoelasticity measuring device (DMA).

Next, the resin structures of the polyimide layer (A) to the polyimide layer (C) will be described. In the present invention, in order to make the ratio E'(A)/E'(B) 2.0 or more, it is preferable that the polyimide layer (A) and the polyimide layer (B) forming the insulating resin layer 110 Polyimides of different compositions were used. Polyimide is formed by imidizing polyamic acid, and contains acid anhydride residues and diamine residues. Here, an acid anhydride residue means a tetravalent group derived from an acid dianhydride, and a diamine residue means a divalent group derived from a diamine compound. In the case of reacting the acid dianhydride and the diamine compound as a raw material with approximately equimolarity, the types and molar ratios of the acid dianhydride residues and diamine residues contained in the polyimide can be compared The kind of raw material and the molar ratio roughly correspond. In addition, in the case of "polyimide" in the present invention, polyimide, polyetherimide, polyesterimide, polysiloxane, etc. Alkyl imides, polybenzimidazolimides, and other resins containing polymers having imide groups in their molecular structure.

Polyimide layer (A): The acid dianhydride residue contained in the polyimide constituting the polyimide layer (A) is not particularly limited as long as the storage elastic modulus E'(A) can be controlled. Anhydride residues derived from tetracarboxylic dianhydride (pyromellitic dianhydride, PMDA) (hereinafter, also referred to as "PMDA residues") and/or tetracarboxylic dianhydride derived from 3,3',4,4'-benzophenone (3,3',4,4'-benzophenone tetracarboxylic dianhydride, BTDA) derived anhydride residue (hereinafter, also referred to as "BTDA" residue). It is preferable to contain PMDA residues and/or BTDA residues in a total of preferably 30 mol % or more, more preferably 50 mol % to 100 mol %, with respect to all acid anhydride residues. Both PMDA residues and BTDA residues have the effect of increasing the storage elastic modulus. Therefore, if the total amount of PMDA residues and/or BTDA residues is less than 30 mol%, the storage elastic modulus E'(A) of the polyimide layer (A) cannot be sufficiently improved, and the first metal layer 101 is inhibited. The effect of the folds becomes insufficient.

Examples of other acid dianhydride residues contained in the polyimide constituting the polyimide layer (A) include 4,4'-oxydiphthalic dianhydride, 3,3', 4,4'-Biphenyltetracarboxylic dianhydride, 2,2',3,3'-benzophenone tetracarboxylic dianhydride or 2,3,3',4'-benzophenone tetracarboxylic acid Dianhydride, 2,3',3,4'-diphenyl ether tetracarboxylic dianhydride, bis(2,3-dicarboxyphenyl) ether dianhydride, 3,3'',4,4''- p-terphenyltetracarboxylic dianhydride, 2,3,3'',4''-p-terphenyltetracarboxylic dianhydride or 2,2'',3,3''-p-terphenyltetracarboxylic dianhydride , 2,2-bis(2,3-dicarboxyphenyl)-propane dianhydride or 2,2-bis(3,4-dicarboxyphenyl)-propane dianhydride, bis(2,3-dicarboxyphenyl) base) methane dianhydride or bis(3,4-dicarboxyphenyl)methane dianhydride, bis(2,3-dicarboxyphenyl)pyridine dianhydride or bis(3,4-dicarboxyphenyl)pyridine dianhydride , 1,1-bis(2,3-dicarboxyphenyl)ethanedianhydride or 1,1-bis(3,4-dicarboxyphenyl)ethanedianhydride, 1,2,7,8-phenanthrene -tetracarboxylic dianhydride, 1,2,6,7-phenanthrene-tetracarboxylic dianhydride or 1,2,9,10-phenanthrene-tetracarboxylic dianhydride, 2,3,6,7-anthracene tetracarboxylic Acid dianhydride, 2,2-bis(3,4-dicarboxyphenyl)tetrafluoropropane dianhydride, 2,3,5,6-cyclohexane dianhydride, 1,2,5,6-naphthalene tetracarboxylic Acid dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5, 6,7-Hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride or 2,7-dichloro Naphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3,6,7-(or 1,4,5,8-)tetrachloronaphthalene-1,4,5,8-(or 2 ,3,6,7-)tetracarboxylic dianhydride, 2,3,8,9-perylene-tetracarboxylic dianhydride, 3,4,9,10-perylene-tetracarboxylic dianhydride, 4,5, 10,11-perylene-tetracarboxylic dianhydride or 5,6,11,12-perylene-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' -Aromatic tetracarboxylic acids such as bis(2,3-dicarboxyphenoxy)diphenylmethane dianhydride, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, etc. Acid dianhydride derived acid dianhydride residue.

In addition, the diamine residue contained in the polyimide constituting the polyimide layer (A) is not particularly limited as long as the storage elastic modulus E'(A) can be controlled, but it is preferably composed of the following: The diamine compound, that is, the diamine residue derived from the diamine compound in which the skeleton of the aromatic ring constituting the main chain is linked at the para position (hereinafter, also referred to as "para position linking diamine residue"). It is preferable to contain para-linked diamine residues in a total of preferably 30 mol % or more, more preferably 50 mol % to 100 mol %, with respect to all the diamine residues. Since the para-linked diamine residue has molecular linearity, it has an effect of suppressing a decrease in the storage elastic modulus E'(A) of the polyimide layer (A). Therefore, by containing the para-linked diamine residue in the above range, the storage elastic modulus of the polyimide layer (A) becomes sufficiently large, and the polyimide layer can be suppressed even at high temperatures during thermocompression bonding. softening of layer (A), and generation of wrinkles of the first metal layer can be suppressed. If the content of the para-linked diamine residue is less than 30 mol%, the storage elastic modulus E'(A) of the polyimide layer (A) cannot be sufficiently increased, and the effect of suppressing the wrinkles of the first metal layer 101 become inadequate.

As a representative example of the para-linked diamine residue, 2,2'-dimethyl-4,4'-diaminobiphenyl (2,2'-dimethyl-4,4'-diamino biphenyl, m-TB), 2,2'-diethyl-4,4'-diaminobiphenyl (2,2'-diethyl-4,4'-diamino biphenyl, m-EB), 2,2'- Diethoxy-4,4'-diaminobiphenyl (2,2'-diethoxy-4,4'-diamino biphenyl, m-EOB), 2,2'-dipropoxy-4,4' -diaminobiphenyl (2,2'-dipropoxy-4,4'-diamino biphenyl, m-POB), 2,2'-n-propyl-4,4'-diaminobiphenyl (2,2 '-n-propyl-4,4'-diamino biphenyl, m-NPB), 2,2'-divinyl-4,4'-diaminobiphenyl (2,2'-divinyl-4,4' -diamino biphenyl, VAB), 4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (4,4'-diamino-2 ,2'-bis(trifluoromethyl)biphenyl, TFMB), 4,4'-bis(4-aminophenoxy)biphenyl (4,4'-bis(4-aminophenoxy)biphenyl, BAPB), 2,2 '-bis[4-(4-aminophenoxy)phenyl]propane (2,2'-bis[4-(4-aminophenoxy)phenyl]propane, BAPP), bis[4-(4-aminophenoxy) Phenyloxy)phenyl]ether (bis[4-(4-aminophenoxy)phenyl]ether, BAPE), bis[4-(4-aminophenoxy)phenyl]pyridine, 1,4-bis(4 -aminophenoxy)benzene (1,4-bis(4-aminophenoxy)benzene, TPE-Q), 4,4'-diaminodiphenyl ether (4,4'-diaminodiphenyl ether, DAPE), etc. A diamine residue derived from a diamine compound. Among the para-linked diamine residues, it is particularly preferable to use 2,2′-dimethyl-4,4′- Diaminobiphenyl (m-TB) and 2,2'-bis[4-(4-aminophenoxy)phenyl]propane (BAPP) derived diamine residues.

In addition, in this specification, the hydrogen atoms in the two terminal amine groups of the "diamine compound" may be substituted, for example, -NR ₁ R ₂ (here, R ₁ and R ₂ independently mean an alkyl group and other arbitrary substituents).

Polyimide layer (B): The acid dianhydride residue contained in the polyimide constituting the polyimide layer (B) is not particularly limited as long as the storage elastic modulus E'(B) can be controlled. , to contain PMDA residues in the range of preferably 30 mol% or more, more preferably 50 mol% to 100 mol%, and/or 3,3',4,4'-biphenyltetracarboxylic acid An acid anhydride residue derived from dianhydride (3,3′,4,4′-biphenyl tetracarboxylic dianhydride, BPDA) (hereinafter also referred to as “BPDA residue”) is preferable. BPDA residues can control the storage elastic modulus in the high temperature region by adjusting the content. When the total amount of PMDA residues and/or BPDA residues is less than 30 mol%, sufficient chemical adhesion to the second metal layer 102 may not be obtained in some cases.

As other acid dianhydride residues contained in the polyimide constituting the polyimide layer (B), the same acid dianhydride residues as those listed in the polyimide layer (A) can be used. base.

In addition, the diamine residue contained in the polyimide constituting the polyimide layer (B) is not particularly limited as long as the storage elastic modulus E'(B) can be controlled. Residues, the diamine residue derived from a flexible diamine compound (hereinafter also referred to as "bending Sexual diamine residues") are preferred. Here, the flexible diamine compound means a diamine compound in which the aromatic ring constituting the main chain has a highly flexible linking group such as -O-, -CH ₂ -, and more preferably includes a meta linking group. By containing the flexible diamine residue, the storage elastic modulus at a temperature equal to or higher than Tg can be lowered, and the thermocompression bonding property and adhesiveness with the second metal layer 102 can be improved. If the total amount of flexible diamine residues is less than 50 mol %, the storage elastic modulus of the polyimide layer (B) may become too high, and the thermocompression bonding property and adhesion with the second metal layer 102 may be too high. reduced sex.

Preferred specific examples of flexible diamine residues include 1,3-bis(4-aminophenoxy)benzene (1,3-bis(4-aminophenoxy)benzene, TPE-R), 1, 3-bis(3-aminophenoxy)benzene (1,3-bis(3-aminophenoxy)benzene, APB), 4,4'-[2-methyl-(1,3-phenylene)bis Oxygen]bisaniline, 4,4'-[4-methyl-(1,3-phenylene)dioxy]bisaniline, 4,4'-[5-methyl-(1,3- Phenyl)dioxy]bisaniline, 3,3'-diaminodiphenylmethane, 3,3'-diaminodiphenylpropane, 3,3'-diaminodiphenylsulfide, 3,3'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl Methane, 3,4'-diaminodiphenylpropane, 3,4'-diaminodiphenylsulfide, 3,3'-diaminobenzophenone, (3,3'-diamine base) diphenylamine, 1,4-bis(3-aminophenoxy)benzene, 3-[4-(4-aminophenoxy)phenoxy]aniline, 3-[3-(4 -aminophenoxy)phenoxy]aniline, bis[4-(3-aminophenoxy)phenyl]methane, bis[4-(3-aminophenoxy)phenyl]propane, bis [4-(3-aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)phenyl]pyridine, bis[4-(3-aminophenoxy)]di Benzophenone, bis[4,4'-(3-aminophenoxy)]benzoylaniline, 4-[3-[4-(4-aminophenoxy)phenoxy]phenoxy ]aniline, 4,4'-[oxybis(3,1-phenoxy)]bisaniline, 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP) Diamine residues derived from diamine compounds. Of these, derived from 1,3-bis(4-aminophenoxy)benzene (TPE-R), 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP) The diamine residue of has excellent flexibility, so it can reduce the storage elastic modulus of the polyimide layer (B) and impart flexibility, which is most preferable.

As other diamine residues contained in the polyimide constituting the polyimide layer (B), the same diamine residues as those listed in the polyimide layer (A) can be used. .

In the polyimides constituting the polyimide layer (A) and the polyimide layer (B), by selecting the types of the acid dianhydride residues and diamine residues and using two or more acid di The respective molar ratios in the case of anhydride residues or diamine residues can control the thermal expansion coefficient, storage elastic modulus, tensile elastic modulus, and the like. In addition, in the polyimide constituting the polyimide layer (A) and the polyimide layer (B), in the case of having a plurality of structural units of polyimide, it may exist in the form of a block, They may also be present randomly, but are preferably present randomly.

Polyimide layer (C): The resin structure and storage elastic modulus of the polyimide constituting the polyimide layer (C) are not particularly limited, and known structures can be used. In addition, in order to ensure the dimensional stability of the insulating resin layer 110 as a whole, the coefficient of thermal expansion (coefficient of thermal expansion, CTE) of the polyimide layer (C) is preferably 30 ppm/K or less, more preferably -5 ppm/K～ Low expansion resin layer in the range of 25 ppm/K.

The polyimides constituting the polyimide layer (A) to polyimide layer (C) can be suitably formulated such as plasticizers, other hardening resin components such as epoxy resins, hardeners, hardening accelerators, and organic fillers. , inorganic fillers, coupling agents, flame retardants, etc. as optional components.

(Synthesis of polyimide) In general, polyimide can be produced by reacting tetracarboxylic dianhydride and diamine compound in a solvent, producing polyamic acid, and heating to close the ring. For example, a tetracarboxylic dianhydride and a diamine compound are dissolved in an organic solvent in an approximately equimolar manner, and the polymerization reaction is carried out by stirring at a temperature in the range of 0° C. to 100° C. for 30 minutes to 24 hours, thereby obtaining the Polyamide acid which is the precursor of polyimide. When performing the reaction, the reaction components are dissolved so that the precursor to be produced is in the range of 5% by weight to 30% by weight, preferably 10% by weight to 20% by weight, in the organic solvent. Examples of the organic solvent used in the polymerization reaction include: N,N-dimethylformamide (N,N-dimethyl formamide, DMF), N,N-dimethylacetamide (N,N-dimethyl acetamide, DMAc), N,N-diethylacetamide, N-methyl-2-pyrrolidone (N-methyl-2-pyrrolidone, NMP), 2-butanone, dimethylsulfoxide (dimethylsulfoxide, DMSO), hexamethylphosphoramide, N-methylcaprolactam, dimethyl sulfate, cyclohexanone, dioxane, tetrahydrofuran, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, cresol etc. These solvents may be used in combination of two or more, and aromatic hydrocarbons such as xylene and toluene may further be used in combination. In addition, the usage amount of such an organic solvent is not particularly limited, but it is preferably adjusted so that the concentration of the polyamic acid solution obtained by the polymerization reaction becomes about 5% by weight to 30% by weight.

The synthesized polyamic acid is usually advantageously used as a reaction solvent solution, but it can be concentrated, diluted or replaced with other organic solvents if necessary. In addition, since polyamic acid is generally excellent in solvent solubility, it can be used advantageously. The viscosity of the polyamic acid solution is preferably within a range of 500 cP to 100,000 cP. If it deviates from the above-mentioned range, defects such as thickness unevenness and streaks are likely to occur on the film at the time of coating operation with a coater or the like. The method for imidizing polyamic acid is not particularly limited. For example, the following heat treatment can be preferably adopted: in the solvent, at a temperature in the range of 80° C. to 400° C. for 1 hour to 24 hours. hours for heating etc.

The weight average molecular weight of polyamic acid, which is a precursor of polyimide constituting the polyimide layer (A) to polyimide layer (C), is preferably within the range of, for example, 10,000 to 400,000, more preferably In the range of 50,000 to 350,000. When the weight-average molecular weight is less than 10,000, the strength of the insulating resin layer 110 tends to decrease and become brittle easily. On the other hand, when the weight average molecular weight exceeds 400,000, the viscosity of the polyamic acid solution becomes high, and defects such as uneven thickness and streaks are likely to occur during coating operations.

<Thickness and ratio of each layer> The thicknesses of the polyimide layer (A) and the polyimide layer (B) are not particularly limited, but are each preferably 1 μm or more, more preferably 2 μm to 10 μm in order to ensure adhesion to the metal foil Inside.

In order to suppress wrinkles in the first metal layer 101 during thermocompression bonding, the ratio of the thickness of the polyimide layer (A) to the entire thickness of the insulating resin layer 110 is preferably in the range of 3% to 45%, more preferably In the range of 4% to 20%. If the thickness ratio is less than 3%, the effect of suppressing wrinkles of the first metal layer 101 may not be sufficiently obtained during thermocompression bonding, and if the thickness ratio exceeds 45%, the ratio of the low-expansion resin layer in the insulating resin layer 110 will decrease. , so there is a tendency for the dimensional stability of the insulating resin layer 110 to deteriorate.

In addition, in order to ensure the adhesion with the second metal layer 102, the ratio of the thickness of the polyimide layer (B) to the entire thickness of the insulating resin layer 110 is preferably in the range of 3% to 45%, more preferably 4%. %~20% range. When the thickness ratio is less than 3%, the adhesiveness by thermocompression bonding may become insufficient, and if the thickness ratio exceeds 45%, the ratio of the low-expansion resin layer in the insulating resin layer 110 decreases, so the insulating resin layer 110 exists. Tendency to deteriorate dimensional stability.

The thickness of the polyimide layer (C) is not particularly limited, and can be appropriately set according to the purpose of use. For example, it is preferably within a range of 3 μm to 75 μm, more preferably within a range of 8 μm to 50 μm. In addition, in order to ensure the dimensional stability of the insulating resin layer 110, the ratio of the thickness of the polyimide layer (C) to the overall thickness of the insulating resin layer 110 is preferably 30% or more, more preferably 60% to 92%. In the range.

Regarding the insulating resin layer 110, in order to reduce the dielectric loss during high-frequency signal transmission, the dielectric loss tangent at 10 GHz measured with a split post dielectric resonator (SPDR) as the entire insulating resin layer (Df) is preferably 0.004 or less. In order to improve the transmission loss of the circuit board, it is particularly important to control the dielectric loss tangent of the insulating resin layer, and by setting the dielectric loss tangent within the above-mentioned range, the effect of reducing transmission loss increases. Therefore, when the metal-clad laminate of the present invention is used as a material for a circuit board for high-frequency applications, transmission loss can be efficiently reduced. If the dielectric loss tangent at 10 GHz exceeds 0.004, problems such as increased loss of electrical signals on the transmission path of high-frequency signals are likely to occur. The lower limit of the dielectric loss tangent at 10 GHz is not particularly limited, but control of the physical properties of the insulating resin layer 110 needs to be considered.

<The first metal layer and the second metal layer> The metals constituting the first metal layer 101 and the second metal layer 102 are not particularly limited as long as they can be used as a material for the wiring layer of the FPC, for example, copper, aluminum, stainless steel, iron, silver, palladium, Metals in nickel, chromium, molybdenum, tungsten, zirconium, gold, cobalt, titanium, tantalum, zinc, lead, tin, silicon, bismuth, indium, or alloys of these, etc. From the viewpoint of adhesiveness, metal foil is preferably used for the first metal layer 101 and the second metal layer 102 . Copper foil is particularly preferable in terms of conductivity. In addition, when the metal-clad laminate 100 and the metal-clad laminate 200 are continuously produced, as the metal foil, a metal foil having a predetermined thickness wound into a roll can be used.

The thickness of the first metal layer 101 is not particularly limited, but it is preferably within a range of 6 μm to 18 μm, and more preferably within a range of 9 μm to 12 μm for use as an FPC material. In addition, the tensile modulus of the first metal layer 101 is not particularly limited, but it is preferably in the range of 10 GPa to 100 GPa, more preferably in the range of 15 GPa to 70 GPa in the application as an FPC material. Moreover, when the thickness and tensile elastic modulus of the 1st metal layer 101 are less than the said range, when conveying by a roll-to-roll system, mechanical strength may become insufficient and handleability may fall. On the other hand, when the thickness and tensile elastic modulus of the first metal layer 101 are larger than the above-mentioned range, the handleability becomes good, but on the other hand, the flexibility is lowered. Wrinkles hardly occur on the first metal layer 101 at this time. However, when the thickness and tensile elastic modulus of the first metal layer 101 are set within the above-mentioned ranges in order to balance the mechanical strength and flexibility required for use as an FPC material, when thermocompression bonding at high temperature Wrinkles are likely to occur, and therefore, the effects of the present invention are remarkably exhibited.

The thickness of the second metal layer 102 is not particularly limited, but it is preferably within a range of 6 μm to 18 μm, and more preferably within a range of 9 μm to 12 μm for use as an FPC material. In addition, the tensile modulus of the second metal layer 102 is not particularly limited, but it is preferably in the range of 10 GPa to 100 GPa, more preferably in the range of 15 GPa to 70 GPa in the application as an FPC material.

＜Manufacturing method of metal-clad laminate＞ Examples of the method of manufacturing the metal-clad laminate 100 include: [1] A method of applying a polyamic acid solution on a metal foil as the first metal layer 101, drying it, and performing imidization (hereinafter referred to as a casting method); [2] On the metal foil as the first metal layer 101, a polyamic acid solution is applied in a state of simultaneously laminating multiple layers by multi-layer extrusion, dried, and then imidized (hereinafter referred to as for multi-layer extrusion) wait.

The method of [1] includes the following steps, for example: (1a) a step of applying a solution of polyamic acid on the metal foil as the first metal layer 101 and drying it; and (1b) A step of forming a polyimide layer by heat-treating polyamic acid on a metal foil for imidization. By repeating step 1a and step 1b, layers can be sequentially stacked on the first metal layer 101 A polyimide layer (A), a polyimide layer (C), and a polyimide layer (B) are formed. In addition, after performing step 1a repeatedly, in step 1b, imidization may be performed batchwise for a plurality of layers.

The method of [2] can be combined with the method of [1] except that the polyamic acid laminated structure is simultaneously coated and dried by multilayer extrusion in step 1a of the method [1]. The method is implemented in the same way.

In this embodiment, it is preferable to complete the imidization of polyamic acid on the first metal layer 101 . Since the polyimide resin layer is imidized while being fixed to the first metal layer 101, it is possible to suppress the expansion and contraction change of each polyimide layer during the imidization process, and maintain thickness and dimensional accuracy. .

As shown in FIG. 3 , the metal-clad laminate 200 can be manufactured by thermocompression bonding the metal foil 102A as the second metal layer 102 to the build-up layer 110 a of the insulating resin layer 110 of the metal-clad laminate 100 . As a temperature condition of thermocompression bonding, it is preferable to perform it in the range of Tg+20 degreeC to Tg+90 degreeC with respect to the glass transition temperature Tg of a polyimide layer (B).

In the metal-clad laminate 200 having the above structure, in order to ensure the reliability after being processed into a circuit board such as FPC, the peel strength between the second metal layer 102 and the polyimide layer (B) is preferably 0.7 kN/m or more, More preferably, it is 1.0 kN/m or more.

<Third Embodiment> A third embodiment as an application example of the present invention will be described with reference to FIGS. 4 and 5 . As shown in FIG. 4 and FIG. 5 , a metal-clad laminate can be produced by arranging two metal-clad laminates 100 so that the polyimide layers (B) face each other, and thermocompression-bonding the laminated layers 110 a 300. The metal-clad laminate 300 of this embodiment has the structure of first metal layer 101/polyimide layer (A)/polyimide layer (C)/polyimide layer (B)/polyimide layer laminated in this order. A double-sided metal-clad laminate with a structure of amine layer (B)/polyimide layer (C)/polyimide layer (A)/first metal layer 101 .

<Fourth Embodiment> A fourth embodiment as an application example of the present invention will be described with reference to FIGS. 6 and 7 . As shown in FIGS. 6 and 7 , the metal-clad laminate 400 can be produced by arranging two metal-clad laminates 100 so that the polyimide layers (B) face each other, and The bonding sheet BS is sandwiched between the metal-clad laminates 100, and the bonding sheet BS is bonded to the two build-up layers 110a by thermocompression. The metal-clad laminate 400 is laminated sequentially with the first metal layer 101/polyimide layer (A)/polyimide layer (C)/polyimide layer (B)/bonding sheet BS/polyimide A double-sided metal-clad laminate with a structure of amine layer (B)/polyimide layer (C)/polyimide layer (A)/first metal layer 101 .

＜Circuit board＞ The metal-clad laminate 100 , the metal-clad laminate 200 , the metal-clad laminate 300 , and the metal-clad laminate 400 of the above embodiment are mainly used as materials for circuit boards such as FPC. That is, it is formed by processing the first metal layer 101 and/or the second metal layer 102 of the metal-clad laminate 100, the metal-clad laminate 200, the metal-clad laminate 300, and the metal-clad laminate 400 into a pattern by a conventional method. As the wiring layer, a circuit board such as an FPC which is one embodiment of the present invention can be manufactured. Although not shown, the circuit board according to the preferred embodiment has the first metal layer 101 and the second metal layer 102 in the metal-clad laminate 100 , the metal-clad laminate 200 , the metal-clad laminate 300 , and the metal-clad laminate 400 . Either or both of the two first metal layers 101 are replaced with wiring layers.

＜Electronic Components/Electronic Equipment＞ An electronic component and an electronic device according to the present embodiment include the circuit board. Examples of the electronic component of this embodiment include liquid crystal displays, organic electroluminescence (EL) displays, display devices such as electronic paper, organic EL lighting, solar cells, touch panels, camera modules, and inverters. , converters and their components, etc. In addition, examples of electronic devices include HDDs, DVDs, mobile phones, smart phones, tablet terminals, electronic control units (electronic control units, ECUs) and power control units (power control units, PCUs) of automobiles. In these electronic components or electronic devices, the circuit board can be preferably used as parts such as wiring of movable parts, cables, connectors, and the like. [Example]

Examples are shown below to describe the features of the present invention in more detail. However, the scope of the present invention is not limited to the examples. In addition, in the following examples, unless otherwise specified, various measurements and evaluations are based on the following contents.

[Measurement of viscosity] The viscosity at 25° C. was measured using an E-type viscometer (manufactured by Brookfield, trade name: DV-II+Pro). The rotation speed was set so that the torque became 10% to 90%, and after 2 minutes from the start of the measurement, the value when the viscosity was stable was read.

[Measurement of weight average molecular weight] The measurement was performed with a gel permeation chromatography (manufactured by Tosoh Corporation, trade name: HLC-8420GPC). Polystyrene was used as a standard substance, and N,N-dimethylacetamide was used as an eluent.

[Measurement of Coefficient of Thermal Expansion (CTE)] For a polyimide film with a size of 3 mm×20 mm, a thermomechanical analyzer (manufactured by Hitachi High-Tech Science, trade name: TMA6100) was used to apply a load of 5.0 g while Raise the temperature from 30°C to 270°C at a certain heating rate, and then keep at the temperature for 10 minutes, then cool at a rate of 5°C/min, and obtain the average thermal expansion coefficient (thermal expansion coefficient) from 250°C to 100°C.

[Measurement of glass transition temperature (Tg) and storage elastic modulus] For a polyimide film with a size of 5 mm × 20 mm, using a dynamic viscoelasticity measurement device (DMA: manufactured by TA Instruments (TA Instruments), trade name: RSA3), the heating rate will be from 30 ° C to 400 ° C The measurement was performed under the conditions of 5° C./min and a frequency of 1 Hz. The glass transition temperature was determined from the maximum temperature of tan δ based on the main dispersion.

[Measurement of Peel Strength] Etch and remove the copper foil (first copper foil layer) on the coated side of the flexible copper-clad laminate to obtain a single-sided copper-clad laminate, and the copper foil (second copper foil) of the single-sided copper-clad laminate layer) with a width of 1.0 mm for circuit processing to prepare samples, the surface of the polyimide layer was fixed to the aluminum plate with double-sided tape, and Tensilon (Tensilon) testing machine (manufactured by Toyo Seiki Seisakusho Co., Ltd., trade name: Ste Graf (Strograph) VE-1D) for determination. The copper foil was stretched at a speed of 50 mm/min in a direction of 180 degrees, and the median strength at the time of peeling 10 mm was obtained. The case where the peel strength is 1.3 kN/m or more is judged as "◎", the case where the peel strength is 1.0 kN/m or more and less than 1.3 kN/m is judged as "○", and the peel strength is 0.7 kN/m or more and The case where it was less than 1.0 kN/m was judged as "Δ", and the case where the peel strength was less than 0.7 kN/m was judged as "×".

[Evaluation of appearance shape] The appearance evaluation of the copper foil (1st copper foil layer) on the coating surface side in a flexible copper-clad laminated board was performed. Cut out the laminated sample into a sheet with a size of 350 mm × 250 mm, and observe it visually. If the appearance shape is good and no wrinkles occur, it is judged as "◎", and if there is a local defect that does not affect the circuit processing. The case of horizontal wrinkles is judged as "○", the case of horizontal wrinkles that do not affect circuit processing is judged as "△" on the entire surface, and the case of horizontal wrinkles that affect circuit processing is generated on the entire surface The case of is judged as "×".

[Measurement of tensile modulus of elasticity] After the copper foil was cut out to a width of 12.7 mm, it was annealed at 380°C for 15 minutes, and then measured using a tensile compression tester (manufactured by Toyo Seiki Seisakusho Co., Ltd., trade name: Strograph R-1) . Stretching was carried out at a chuck spacing of 101.6 mm and a scanning speed of 10 mm/min, and the tensile modulus of elasticity was calculated according to the slope of the obtained stress-displacement curve at 0.2% displacement.

[Measurement of dielectric loss tangent] The dielectric of the polyimide film at a frequency of 10 GHz was measured using a vector network analyzer (manufactured by Agilent, trade name: E8363C) and a separated column dielectric resonator (SPDR resonator). Loss tangent. In addition, the material used in the measurement is a polyimide film prepared by etching and removing the copper foil layer of the flexible copper-clad laminate. The material after standing for 24 hours.

The codes used in Examples and Comparative Examples represent the following compounds. PMDA: pyromellitic dianhydride BTDA: 3,3',4,4'-Benzophenone tetracarboxylic dianhydride BPDA: 3,3',4,4'-Biphenyltetracarboxylic dianhydride m-TB: 2,2'-dimethyl-4,4'-diaminobiphenyl TPE-R: 1,3-bis(4-aminophenoxy)benzene BAPP: 2,2-bis[4-(4-aminophenoxy)phenyl]propane DMAc: N,N-Dimethylacetamide Copper foil 1: Rolled copper foil, thickness 9 μm, tensile elastic modulus after annealing treatment 36 GPa Copper foil 2: rolled copper foil, thickness 12 μm, tensile elastic modulus after annealing treatment 36 GPa Copper foil 3: rolled copper foil, thickness 18 μm, tensile elastic modulus after annealing treatment 36 GPa Copper foil 4: rolled copper foil, thickness 18 μm, tensile elastic modulus after annealing treatment 18 GPa

(Synthesis Example 1) 21.43 parts by weight of m-TB (100.92 parts by mole) was added to 255.0 parts by weight of DMAc, and stirred at room temperature for 30 minutes or more to completely dissolve it. Next, 16.26 parts by weight of PMDA (74.56 parts by mole) and 7.31 parts by weight of BPDA (24.85 parts by mole) were added, and stirred at room temperature for 4 hours to obtain a polyamic acid with a viscosity of 27,400 cP and a weight average molecular weight of 117,000. Solution 1.

On the substrate, the polyamic acid solution 1 was uniformly applied so that the thickness after curing was about 25 μm, and then heat-dried at 140° C. or lower to remove the solvent. Furthermore, heat treatment was performed by raising the temperature stepwise from 140° C. to 360° C. to complete the imidization, and the thus obtained polyimide film 1 was produced. The obtained polyimide film 1 had a CTE of 23 ppm/K and was non-thermoplastic.

(Synthesis Example 2) 10.55 parts by weight of TPE-R (36.10 parts by mole) and 7.66 parts by weight of m-TB (33.10 parts by mole) were added to 264.0 parts by weight of DMAc, and stirred at room temperature for more than 30 minutes to completely dissolve. Next, add 10.89 parts by weight of PMDA (49.93 parts by mole) and 6.90 parts by weight of BTDA (21.40 parts by mole), and stir at room temperature for 4 hours to obtain a polyamic acid with a viscosity of 3,800 cP and a weight average molecular weight of 180,000. Solution 2.

Polyimide film 2 produced in the same manner as in Synthesis Example 1 had a Tg of 300°C and a storage elastic modulus of 1.2×10 ⁹ Pa (270°C), 1.2×10 ⁹ Pa (275°C), and 2.0×10 ⁸ Pa (350°C) and 1.3×10 ⁸ Pa (400°C).

(Synthesis Example 3) 23.20 parts by weight of BAPP (56.53 parts by mole) was added to 264.0 parts by weight of DMAc, and stirred at room temperature for 30 minutes or more to completely dissolve it. Next, 11.95 parts by weight of PMDA (54.77 parts by mole) and 0.85 parts by weight of BPDA (2.88 parts by mole) were added, and stirred at room temperature for 4 hours to obtain a polyamic acid with a viscosity of 1,700 cP and a weight average molecular weight of 200,000. Solution 3.

Polyimide film 3 produced in the same manner as in Synthesis Example 1 had a Tg of 320°C and a storage elastic modulus of 1.5×10 ⁹ Pa (270°C), 1.0×10 ⁸ Pa (275°C), and 6.3×10 ⁷ Pa (350°C) and 1.9×10 ⁷ Pa (400°C).

(Synthesis Example 4) 17.94 parts by weight of TPE-R (61.36 parts by mole) and 0.69 parts by weight of m-TB (3.23 parts by mole) were added to 264.0 parts by weight of DMAc, and stirred at room temperature for more than 30 minutes to completely dissolve. Next, 11.63 parts by weight of BPDA (39.53 parts by mole) and 5.75 parts by weight of PMDA (26.35 parts by mole) were added, and stirred at room temperature for 4 hours to obtain a polyamic acid with a viscosity of 2,500 cP and a weight average molecular weight of 121,000. Solution 4.

The polyimide film 4 produced in the same manner as in Synthesis Example 1 had a Tg of 225° C. and a storage elastic modulus of 1.0×10 ⁸ Pa (275° C.).

(Synthesis Example 5) 15.33 parts by weight of TPE-R (52.43 parts by mole) and 2.78 parts by weight of m-TB (13.11 parts by mole) were added to 264.0 parts by weight of DMAc, and stirred at room temperature for more than 30 minutes to completely dissolve. Next, 12.79 parts by weight of BPDA (43.45 parts by mole) and 5.10 parts by weight of PMDA (23.40 parts by mole) were added, and stirred at room temperature for 4 hours to obtain a polyamic acid with a viscosity of 2,300 cP and a weight average molecular weight of 118,000. Solution 5.

The polyimide film 5 prepared in the same manner as in Synthesis Example 1 had a Tg of 220° C. and a storage elastic modulus of 4.4×10 ⁷ Pa (270° C.).

[Example 1] The polyamic acid solution 2 was applied on the copper foil 1 so that the thickness after curing was 2 μm, and then heat-dried at 140° C. or lower to remove the solvent. Polyamic acid solution 1 was applied thereon so that the thickness after curing was 21 μm, and then heat-dried at 140° C. or lower to remove the solvent. Further, the polyamic acid solution 3 was applied thereon so that the thickness after curing became 2 μm, and then heat-dried at 140° C. or lower to remove the solvent. Then, the temperature was increased stepwise from 140° C. to 360° C. for imidization, and a single-sided copper-clad laminate 1 was prepared. Copper foil 2 was placed on the polyimide layer side of the obtained single-sided copper-clad laminate 1, and thermal lamination was performed continuously at a lamination pressure of 1 kN/cm ² and a lamination temperature of 350°C using a hot roll lamination machine. , to obtain a flexible copper-clad laminate 1 . Table 1 shows the evaluation results of the flexible copper-clad laminate 1.

[Example 2] Except having used the copper foil 2 instead of the copper foil 1, it carried out similarly to Example 1, and obtained the flexible copper clad laminated board 2. Table 1 shows the evaluation results of the flexible copper-clad laminate 2.

[Example 3] Except having used the copper foil 3 instead of the copper foil 1, it carried out similarly to Example 1, and obtained the flexible copper clad laminated board 3. Table 1 shows the evaluation results of the flexible copper-clad laminate 3 .

[Example 4] Except having used the copper foil 4 instead of the copper foil 1, it carried out similarly to Example 1, and obtained the flexible copper clad laminated board 4. Table 1 shows the evaluation results of the flexible copper-clad laminate 4 .

[Example 5] The flexible copper-clad laminated board 5 was obtained like Example 1 except having used the copper foil 3 instead of the copper foil 1, and having made lamination temperature 400 degreeC. Table 1 shows the evaluation results of the flexible copper-clad laminate 5 .

[Example 6] Except that copper foil 2 was used instead of copper foil 1, polyamic acid solution 4 was used instead of polyamic acid solution 3, and the lamination temperature was set to 275°C, a flexible copper clad laminate was obtained in the same manner as in Example 1. board6. Table 1 shows the evaluation results of the flexible copper-clad laminate 6 .

[Example 7] Except that copper foil 2 was used instead of copper foil 1, polyamic acid solution 5 was used instead of polyamic acid solution 3, and the lamination temperature was set to 270°C, a flexible copper clad laminate was obtained in the same manner as in Example 1. plate 7. Table 1 shows the evaluation results of the flexible copper-clad laminate 7 .

[Example 8] In addition to using copper foil 2 instead of copper foil 1, using polyamic acid solution 3 instead of polyamic acid solution 2; using polyamic acid solution 5 instead of polyamic acid solution 3; and setting the lamination temperature to 270 Except for ℃, it carried out similarly to Example 1, and the flexible copper-clad laminated board 8 was obtained. Table 1 shows the evaluation results of the flexible copper-clad laminate 8 .

Comparative example 1 A flexible copper-clad laminate 9 was obtained in the same manner as in Example 1, except that copper foil 2 was used instead of copper foil 1 and polyamic acid solution 2 was used instead of polyamic acid solution 3 . Table 1 shows the evaluation results of the flexible copper-clad laminate 9 .

Comparative example 2 In addition to using copper foil 2 instead of copper foil 1, using polyamic acid solution 5 instead of polyamic acid solution 2; using polyamic acid solution 5 instead of polyamic acid solution 3; and setting the lamination temperature to 270 Except for ℃, it carried out similarly to Example 1, and the flexible copper-clad laminated board 10 was obtained. Table 1 shows the evaluation results of the flexible copper-clad laminate 10 .

In addition, "layer (A)" and "layer (B)" in Table 1 mean "polyimide layer (A)" and "polyimide layer (B)", respectively. In addition, both E'(A) and E'(B) in Table 1 mean the storage elastic modulus at the lamination temperature.

[Table 1] polyamide solution first copper foil layer Tg of layer (B) [°C] Lamination temperature [°C] E'(A) [Pa] E'(B) [Pa] E'(A)/E'(B) Appearance shape Peel strength Layer (A) Layer (B) Example 1 2 3 copper foil 1 320 350 2.0E+08 6.3E+07 3.2 △ 〇 Example 2 2 3 Copper foil 2 320 350 2.0E+08 6.3E+07 3.2 〇 〇 Example 3 2 3 Copper foil 3 320 350 2.0E+08 6.3E+07 3.2 ◎ 〇 Example 4 2 3 Copper foil 4 320 350 2.0E+08 6.3E+07 3.2 〇 〇 Example 5 2 3 Copper foil 3 320 400 1.3E+08 1.9E+07 6.8 〇 ◎ Example 6 2 4 Copper foil 2 225 275 1.2E+09 1.0E+08 12.0 ◎ ◎ Example 7 2 5 Copper foil 2 220 270 1.2E+09 4.4E+07 27.3 ◎ ◎ Example 8 3 5 Copper foil 2 220 270 1.5E+09 4.4E+07 34.1 〇 ◎ Comparative example 1 2 2 Copper foil 2 300 350 2.0E+08 2.0E+08 1.0 ◎ x Comparative example 2 5 5 Copper foil 2 220 270 4.4E+07 4.4E+07 1.0 x ◎

The polyimide films 1 to 1 prepared by etching and removing the copper foil layers of the flexible copper-clad laminates 1 to 10 obtained in Examples 1 to 8 and Comparative Examples 1 to 2 The dielectric loss tangent (Df) of the polyimide film 10 at a frequency of 10 GHz is shown in Table 2.

[Table 2] Polyimide membrane Dielectric loss tangent (Df) Example 1 1 0.0035 Example 2 2 0.0035 Example 3 3 0.0035 Example 4 4 0.0035 Example 5 5 0.0034 Example 6 6 0.0038 Example 7 7 0.0038 Example 8 8 0.0039 Comparative example 1 9 0.0035 Comparative example 2 10 0.0037

As mentioned above, although the embodiment of this invention was demonstrated in detail for the purpose of illustration, this invention is not limited to the said embodiment, Various deformation|transformation is possible.

100, 200, 300, 400: Metal-clad laminates 101: The first metal layer 102: Second metal layer 102A: metal foil 110: insulating resin layer 110a: stacking layer (A): polyimide layer (A) (B): polyimide layer (B) (C): polyimide layer (C) BS: Bonding piece

FIG. 1 is a schematic cross-sectional view showing the structure of a metal-clad laminate according to a first embodiment of the present invention. 2 is a schematic cross-sectional view showing the structure of a metal-clad laminate according to a second embodiment of the present invention. 3 is an explanatory view showing a method of manufacturing a metal-clad laminate according to a second embodiment of the present invention. 4 is an explanatory view showing a method of manufacturing a metal-clad laminate according to a third embodiment of the present invention. 5 is a schematic cross-sectional view showing the structure of a metal-clad laminate according to a third embodiment of the present invention. Fig. 6 is an explanatory view showing a method of manufacturing a metal-clad laminate according to a fourth embodiment of the present invention. 7 is a schematic cross-sectional view showing the structure of a metal-clad laminate according to a fourth embodiment of the present invention.

100: metal clad laminate

101: The first metal layer

110: insulating resin layer

110a: stacking layer

(A): polyimide layer (A)

(B): polyimide layer (B)

(C): Polyimide layer (C)

Claims (9)

A metal-clad laminate comprising: a first metal layer; and An insulating resin layer is laminated on the first metal layer, and the metal-clad laminate is characterized in that, The insulating resin layer has a polyimide layer (A) in contact with the first metal layer, and a polyimide layer (B) having a resin surface formed on a side opposite to the first metal layer. ), When taking the glass transition temperature Tg of the polyimide layer (B) as a reference, the temperature of the polyimide layer (A) at any temperature within the range from Tg+20°C to Tg+90°C When the storage elastic modulus is E'(A) and the storage elastic modulus of the polyimide layer (B) is E'(B), the ratio of the storage elastic modulus E'(A)/ E'(B) is 2.0 or more. The metal-clad laminate according to claim 1, wherein the insulating resin layer has polyimide laminated between the polyimide layer (A) and the polyimide layer (B). layer (C). The metal-clad laminate according to claim 1 or claim 2, wherein the thickness of the first metal layer is in the range of 6 μm to 18 μm, and the tensile modulus of elasticity is in the range of 10 GPa to 100 GPa . The metal-clad laminate according to claim 1, further comprising a second metal layer laminated in contact with the resin surface of the polyimide layer (B). The metal-clad laminate according to claim 4, wherein the peel strength between the second metal layer and the polyimide layer (B) is 0.7 kN/m or more. A circuit substrate, which is obtained by performing circuit processing on either or both of the first metal layer and the second metal layer in the metal-clad laminate according to Claim 4. A circuit substrate, which is obtained by performing circuit processing on the first metal layer in the metal-clad laminate according to Claim 1. An electronic component, characterized by comprising the circuit substrate as described in Claim 6 or Claim 7. An electronic device, characterized by comprising the circuit substrate as described in Claim 6 or Claim 7.

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