TW202027980A - Metal-clad laminate, circuit board, multilayer circuit board and method of manufacturing the same excellent in dimensional stability of a conductor circuit - Google Patents

Abstract

This invention provides a metal-clad laminate, a circuit board, a multilayer circuit board and a method of manufacturing the same. Provided is a multilayer circuit board which is excellent in dimensional stability of a conductor circuit and has an adhesive layer capable of reducing transmission loss even in transmission of a high-frequency signal. A circuit board (101) includes: an insulating resin layer (10); a conductor circuit layer (50) laminated on one surface of the insulating resin layer (10); and an adhesive layer (30) laminated on the other surface of the insulating resin layer (10). A multilayer circuit board (200) is produced by a method as follows: superimposing an adhesive layer (30) of a first circuit board (101) face to face with a conductor circuit layer (50) of a second circuit board (101), superimposing an adhesive layer (30) of the second circuit board (101) face to face with a conductor circuit layer (50) of any circuit board (110) having no adhesive layer (30), and collectively pressing the same.

Description

Metal-clad laminated board, circuit substrate, multilayer circuit substrate and manufacturing method thereof

The present invention relates to a metal-clad laminated board, a circuit board, a multilayer circuit board with a conductor circuit layer laminated in multiple layers, and a manufacturing method thereof.

In recent years, with the advancement of high-density and high-functionality of electronic equipment, circuit board materials with further dimensional stability or excellent high-frequency characteristics are required. In particular, low dielectric constant and low dielectric loss are important for the characteristics of organic interlayer insulating materials required for high-speed signal processing. In order to cope with the increase in high frequency, a multilayer wiring board in which a liquid crystal polymer (LCP) characterized by a low dielectric constant and a low dielectric loss tangent is used as a dielectric layer has been proposed (for example, Patent Document 1). A multilayer wiring board in which a liquid crystal polymer is used as an insulating layer is manufactured by heating and pressing in a state near the melting point of a liquid crystal polymer base material as a thermoplastic resin. The thermal deformation of the material causes the position of the circuit conductor to shift, and there is a concern that the impedance (impedance) mismatch, etc., will adversely affect the electrical characteristics. In addition, the multilayer wiring board in which the liquid crystal polymer is used as the base layer does not show the anchoring effect when the multilayer bonding interface is smooth, and the interlayer adhesion is insufficient. Therefore, it is necessary to separate the circuit conductor and the liquid crystal polymer base material. The surface roughening treatment also has the problem of complicated manufacturing steps.

Moreover, as a technology related to an adhesive layer mainly composed of polyimide, it has been proposed to apply a cross-linked polyimide resin to the adhesive layer of a coverlay film. The cross-linked polyimide The imine resin is obtained by reacting a polyimide derived from a diamine compound derived from an aliphatic diamine such as a dimer acid with an amino compound having at least two primary amino groups as functional groups (for example, Patent Document 2). The cross-linked polyimide resin of Patent Document 2 has the following advantages: it does not generate volatile components containing cyclic silicone compounds, has excellent solder heat resistance, and is not even in a use environment that is repeatedly exposed to high temperatures. This will reduce the adhesion between the wiring layer and the cover film. However, in Patent Document 2, the possibility of application in high-frequency signal transmission has not been studied. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2005-317953 [Patent Document 2] Japanese Patent Laid-Open No. 2013-1730

[The problem to be solved by the invention] In the future, in multilayer circuit boards, as a directivity to achieve high-frequency signal transmission, it is considered to increase the total thickness of the insulating resin layer or the adhesive layer while maintaining the dimensional stability of the conductor circuit. Realize the improvement of dielectric properties. For this reason, in metal-clad laminates or circuit boards used as materials for multilayer circuit boards, not only these materials but also their structures require different design concepts from those of conventional multilayer circuit boards.

Therefore, an object of the present invention is to provide a multi-layer circuit board having excellent dimensional stability of a conductor circuit and a novel structure capable of reducing transmission loss even in the transmission of high-frequency signals. [Technical means to solve the problem]

The inventors of the present invention conducted diligent studies and found that by using a metal-clad laminate of a specific structure as a material for a multilayer circuit board, the dimensional stability of the conductor circuit can be maintained while maintaining excellent adhesion, while being able to cope with high frequency Signal transmission, thus completing the present invention.

That is, the metal-clad laminated board of the present invention includes: an insulating resin layer; a metal layer laminated on one side of the insulating resin layer; and an adhesive layer laminated on the other side of the insulating resin layer. In addition, the circuit substrate of the present invention includes an insulating resin layer; a conductive circuit layer formed on one side of the insulating resin layer; and an adhesive layer laminated on the other side of the insulating resin layer. Furthermore, in the metal-clad laminate or circuit board of the present invention, the resin constituting the adhesive layer is a thermoplastic resin or a thermosetting resin, and satisfies the following conditions (i) to (iii): (I) The storage elastic modulus at 50°C is below 1800 MPa; (Ii) The maximum storage elastic modulus in the temperature range from 180°C to 260°C is 800 MPa or less; (Iii) The glass transition temperature (Tg) is 180°C or less.

In the metal-clad laminate or circuit board of the present invention, the thermoplastic resin may be an adhesive polyimide containing tetracarboxylic acid residues and diamine residues. In this case, the adhesive polyimide may contain 50 mole parts or more of diamine residues derived from dimer acid type diamines relative to 100 mole parts of the total amount of the diamine residues. The dimer acid type diamine is formed by substituting the two terminal carboxylic acid groups of the dimer acid with a primary aminomethyl group or an amino group.

The metal-clad laminated board of the present invention may be a material of a circuit board obtained by processing the metal layer into wiring.

In the metal-clad laminate or circuit board of the present invention, the adhesive polyimide may contain a total of 90 mol parts or more of the following based on 100 mol parts of the total amount of the tetracarboxylic acid residues. The tetracarboxylic acid residue derived from the tetracarboxylic anhydride represented by the general formula (1) and/or the general formula (2).

[化1]

In the general formula (1), X represents a single bond or a divalent group selected from the following formulae. In the general formula (2), the cyclic moiety represented by Y represents the formation of a 4-membered ring, a 5-membered ring, and 6 A cyclic saturated hydrocarbon group in a ring, a 7-membered ring or an 8-membered ring.

[化2]

In the formula, Z represents -C ₆ H ₄ -, -(CH ₂ )n- or -CH ₂ -CH(-OC(=O)-CH ₃ )-CH ₂ -, and n represents an integer of 1-20 .

In the metal-clad laminate or circuit board of the present invention, the adhesive polyimide may be 50 mol parts or more and 99 mol parts or less with respect to 100 mol parts of the total amount of the diamine residues The diamine residue derived from the dimer acid-type diamine is contained in the range of, and may be contained in the range of 1 mol part or more and 50 mol part or less selected from the following general formulas (B1)~ A diamine residue derived from at least one diamine compound in the diamine compound represented by the general formula (B7).

[化3]

In formulas (B1) to (B7), R ₁ independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, and the linking group A independently represents a group selected from -O-, -S-, -CO-, The divalent group in -SO-, -SO ₂ -, -COO-, -CH ₂ -, -C(CH ₃ ) ₂ -, -NH- or -CONH-, n ₁ independently represents an integer from 0 to 4 ; Among them, from the formula (B3) remove the part that overlaps with the formula (B2), from the formula (B5) remove the part that overlaps with the formula (B4).

The multilayer circuit board of the present invention is formed by stacking a plurality of circuit boards, and is characterized in that it includes at least one of the above-mentioned circuit boards as the circuit board.

The manufacturing method of the multilayer circuit board of the first aspect of the present invention may include: A step of preparing a plurality of circuit substrates, the circuit substrate including an insulating resin layer, a conductive circuit layer formed on one side of the insulating resin layer, and an adhesive layer laminated on the other side of the insulating resin layer; and The step of overlapping and crimping the conductive circuit layer of one circuit substrate and the adhesive layer of the other circuit substrate in an opposing manner.

The manufacturing method of the multilayer circuit board of the second aspect of the present invention may include: A step of preparing a plurality of circuit substrates, the circuit substrate including an insulating resin layer, a conductive circuit layer formed on one side of the insulating resin layer, and an adhesive layer laminated on the other side of the insulating resin layer; and The step of overlapping and crimping the adhesive layer of one circuit substrate and the adhesive layer of the other circuit substrate in an opposing manner. [Effects of the invention]

The metal-clad laminate of the present invention has a structure having a metal layer on one side of the insulating resin layer and an adhesive layer on the other side of the insulating resin layer. Therefore, a multilayer circuit board can be easily manufactured by lamination. It is useful as a material for multilayer circuit boards. In addition, in the case of manufacturing a multilayer circuit board using a metal-clad laminate, it is possible to maintain the dimensional stability of the conductor circuit while ensuring the coating and adhesion to the conductor circuit layer, thereby ensuring the thickness of the entire resin layer. Therefore, by using the metal-clad laminate of the present invention, a multilayer circuit board having good interlayer connections and high reliability can be obtained. In addition, with the multilayer circuit board of the present invention, transmission loss can be reduced even in the transmission of high-frequency signals, and high-density integration or high-density mounting of electronic components can be achieved. In addition, since the multilayer circuit board of the present invention is also excellent in heat resistance, it is also possible to mount a semiconductor wafer with a large amount of heat.

The embodiment of the present invention will be described in detail.

[Metal Clad Laminate] Fig. 1 is a cross-sectional view showing the structure of a metal-clad laminate according to an embodiment of the present invention. The metal-clad laminate 100 of this embodiment includes an insulating resin layer 10; a metal layer 20 laminated on one side of the insulating resin layer 10; and an adhesive layer 30 laminated on the other side of the insulating resin layer 10. That is, the metal-clad laminated board 100 has a structure in which a metal layer 20/insulating resin layer 10/adhesive layer 30 are laminated in this order. If other expressions are used, the metal-clad laminate 100 has an adhesive layer 30 added to the back side (insulation resin layer 10 side) of the single-sided metal-clad laminate 40 formed by laminating the insulating resin layer 10 and the metal layer 20 Structure. In addition, the adhesive layer 30 may be formed on the entire surface of one side of the insulating resin layer 10, or may be formed only on a part.

＜Single-side metal-clad laminated board＞ The structure of the single-sided metal-clad laminate 40 is not particularly limited, and a material that is common as a flexible printed circuit (FPC) material can be used. For example, a commercially available copper-clad laminate can be used. For example, as commercially available copper-clad laminates, R-F705T (trade name) manufactured by Panasonic, Espanex (trade name) manufactured by Nippon Steel Chemical & Materials Co., Ltd., etc. can be used .

(Metal layer) The material of the metal layer 20 is not particularly limited, and examples thereof include copper, stainless steel, iron, nickel, beryllium, aluminum, zinc, indium, silver, gold, tin, zirconium, tantalum, titanium, lead, magnesium, manganese, and these Alloy etc. Among these, copper or copper alloys are particularly preferred. In addition, the material of the wiring layer in the circuit board of this embodiment described later is also the same as that of the metal layer 20.

The thickness of the metal layer 20 is not particularly limited. For example, when a metal foil such as copper foil is used, it is preferably 35 μm or less, and more preferably in the range of 5 μm to 25 μm. From the viewpoint of production stability and handling properties, the lower limit of the thickness of the metal layer is preferably 5 μm. Furthermore, when copper foil is used, it may be rolled copper foil or electrolytic copper foil. In addition, as copper foil, commercially available copper foil can be used.

In addition, the metal foil may be subjected to rust prevention treatment, or surface treatment using, for example, siding, aluminum alcoholate, aluminum chelate, and silane coupling agent for the purpose of improving adhesion.

(Insulating resin layer) The insulating resin layer 10 is not particularly limited as long as it contains a resin having electrical insulating properties. Examples include polyimide, liquid crystal polymer, epoxy resin, phenol resin, polyethylene, polypropylene, and polytetrafluoroethylene. Ethylene, silicone, ethylene tetrafluoroethylene (ETFE), bismaleimide triazine (Bismaleimide Triazine, BT) resin, etc., preferably contain polyimide. Furthermore, the term “polyimine” in the present invention refers to polyimide, polyetherimide, polyesterimide, polysiloxaneimine, in addition to polyimide. , Polybenzimidazole imide and other polymers with imine groups in the molecular structure.

In addition, the insulating resin layer 10 is not limited to a single layer, and a plurality of resin layers may be laminated. In addition, the insulating resin layer 10 preferably includes a non-thermoplastic polyimide layer formed of a non-thermoplastic polyimide. Furthermore, the so-called "non-thermoplastic polyimide" usually refers to a polyimide that does not exhibit adhesiveness even if it is heated and softened. In the present invention, it refers to the use of a dynamic viscoelasticity measuring device (dynamic mechanical analyzer). (Dynamic Mechanical Analyzer, DMA)) Polyimide having a storage elastic modulus of 1.0×10 ⁹ Pa or more at 30°C and a storage elastic modulus of 3.0×10 ⁸ Pa or more at 300°C.

The insulating resin layer 10 can be selected and used from, for example, a commercially available polyimide film, a commercially available liquid crystal polymer film, or a commercially available metal-clad laminate resin used as an insulating substrate. As the polyimide film, Upilex (trade name) manufactured by Ube Industries Co., Ltd., Kapton (trade name) manufactured by Toray Dupont Co., Ltd., card Apical (trade name) manufactured by Kaneka Corporation, Pixeo (trade name) manufactured by Kaneka Corporation, as the liquid crystal polymer film, Kuraray can be used (Kuraray) Vecstar (trade name), BIAC Film (trade name) manufactured by Primatech, etc.

The coefficient of thermal expansion (CTE) of the insulating resin layer 10 is not particularly limited, and may be 10 ppm/K or more, preferably 10 ppm/K or more and 30 ppm/K or less, more preferably 15 ppm /K or more and 25 ppm/K or less. If the CTE is less than 10 ppm/K or more than 30 ppm/K, warpage occurs or dimensional stability is reduced. It can be controlled to a desired CTE by appropriately changing the combination of raw materials used, thickness, and drying/hardening conditions.

Furthermore, the overall coefficient of thermal expansion (CTE) of the resin layer including the insulating resin layer 10 and the adhesive layer 30 is not particularly limited, but is preferably within the range of 10 ppm/K or more and 30 ppm/K or less, and more preferably 15 Within the range of ppm/K or more and 25 ppm/K or less. If the CTE of the entire resin layer is less than 10 ppm/K or exceeds 30 ppm/K, warpage occurs or dimensional stability is reduced.

For example, when the insulating resin layer 10 is applied to a multilayer circuit board, in order to suppress the deterioration of the dielectric loss, the dielectric loss tangent (Tanδ) at 10 GHz may be preferably 0.02 or less, more preferably 0.0005 or more and 0.01 or less Within the range, more preferably within the range of 0.001 or more and 0.008 or less. If the dielectric loss tangent at 10 GHz of the insulating resin layer 10 exceeds 0.02, when it is applied to a multilayer circuit board, defects such as electrical signal loss are likely to occur in the transmission path of high-frequency signals. On the other hand, the lower limit of the dielectric loss tangent at 10 GHz of the insulating resin layer 10 is not particularly limited, and control of the physical properties of the insulating resin layer of the multilayer circuit board can be considered.

For example, when the insulating resin layer 10 is used as an insulating resin layer of a multilayer circuit board, in order to ensure impedance matching, the dielectric constant (ε) at 10 GHz is preferably 4.0 or less. If the dielectric constant of the insulating resin layer 10 at 10 GHz exceeds 4.0, when it is applied to a multilayer circuit board, the dielectric loss of the insulating resin layer 10 is deteriorated and electrical signals are easily generated on the transmission path of high-frequency signals. Loss and other adverse circumstances.

＜Adhesive layer＞ The adhesive layer 30 includes a thermoplastic resin or a thermosetting resin, and satisfies the following conditions: (I) The storage elastic modulus at 50°C is below 1800 MPa; (Ii) The maximum storage elastic modulus from 180°C to 260°C is below 800 MPa; and (Iii) The glass transition temperature (Tg) is 180°C or less. Examples of such resins include polyimide resins, polyimide resins, epoxy resins, phenoxy resins, acrylic resins, polyurethane resins, styrene resins, polyester resins, phenol resins, Polyvinyl resin, polyether resin, polyphenylene sulfide resin, polyethylene resin, polypropylene resin, silicone resin, polyetherketone resin, polyvinyl alcohol resin, polyvinyl butyral resin, styrene-Malay Resins such as amide copolymer, maleimine-vinyl compound copolymer, or (meth)acrylic copolymer, benzoxazine resin, bismaleimide resin and cyanate ester resin, etc. Among these, a resin that satisfies the conditions (i) to (iii) or is designed to satisfy the conditions (i) to (iii) is selected and used in the adhesive layer 30.

When the adhesive layer 30 is a thermosetting resin, it may contain an organic peroxide, a curing agent, a curing accelerator, etc., and a curing agent and a curing accelerator, or a catalyst and a co-catalyst may be used in combination as necessary. What is necessary is just to judge the addition amount of a hardening agent, a hardening accelerator, a catalyst, a co-catalyst, and an organic peroxide, and the presence or absence of addition within the range which can ensure the said conditions (i)-(iii).

As shown in conditions (i) and (ii), the adhesive layer 30 has a storage elastic modulus at 50°C of 1800 MPa or less, and the maximum storage elastic modulus in the temperature range from 180°C to 260°C is Below 800 MPa. The characteristics of the adhesive layer 30 are considered to be the main reason for alleviating the internal stress during thermal compression bonding and maintaining the dimensional stability after circuit processing. In addition, the storage elastic modulus at the upper limit temperature (260° C.) of the temperature range of the adhesive layer 30 is preferably 800 MPa or less, and more preferably in the range of 500 MPa or less. By setting such a storage elastic modulus, even after the solder reflow step after circuit processing, it is difficult to generate warpage.

As shown in the condition (iii), the adhesive layer 30 may have a glass transition temperature (Tg) of 180° C. or lower, preferably 160° C. or lower. By setting the glass transition temperature of the adhesive layer 30 to 180° C. or lower, thermocompression bonding at low temperatures can be performed. Therefore, the internal stress generated during lamination can be alleviated and dimensional changes can be suppressed. If the Tg of the adhesive layer 30 exceeds 180° C., the temperature at the time of bonding interposed between the insulating resin layer 10 and an arbitrary circuit board becomes high, which may impair dimensional stability.

(CTE of bonding layer) Although the thermoplastic resin or thermosetting resin constituting the adhesive layer 30 has high thermal expansion properties, it has low elasticity and a low glass transition temperature. Therefore, even if the CTE exceeds 30 ppm/K, the internal stress generated during lamination can be alleviated. . Therefore, the CTE of the adhesive layer 30 is preferably 35 ppm/K or more, more preferably in the range of 35 ppm/K or more and 200 ppm/K, and still more preferably in the range of 35 ppm/K or more and 150 ppm/K. Inside. By appropriately changing the combination of raw materials used, thickness, and drying/curing conditions, the adhesive layer 30 having a desired CTE can be produced.

(Dielectric loss tangent of bonding layer) For example, when the adhesive layer 30 is applied to a multilayer circuit board, in order to suppress the deterioration of the dielectric loss, the dielectric loss tangent (Tanδ) at 10 GHz may be preferably 0.004 or less, more preferably 0.003 or less, and even more preferably 0.002 or less . If the dielectric loss tangent at 10 GHz of the adhesive layer 30 exceeds 0.004, when it is applied to a multilayer circuit board, defects such as electrical signal loss may easily occur in the transmission path of high-frequency signals. On the other hand, the lower limit of the dielectric loss tangent at 10 GHz of the adhesive layer 30 is not particularly limited.

(The dielectric constant of the bonding layer) For example, when the adhesive layer 30 is applied to a multilayer circuit board, in order to ensure impedance matching, the dielectric constant at 10 GHz is preferably 4.0 or less. If the dielectric constant of the bonding layer 30 at 10 GHz exceeds 4.0, when applied to a multilayer circuit board, the dielectric loss of the bonding layer 30 will deteriorate and electrical signals will easily be generated on the transmission path of high-frequency signals. Loss and other adverse circumstances.

(filler) If necessary, the adhesive layer 30 may also contain fillers. Examples of the filler include silicon dioxide, aluminum oxide, magnesium oxide, beryllium oxide, boron nitride, aluminum nitride, silicon nitride, aluminum fluoride, calcium fluoride, and metal salts of organic phosphinic acid. These can be used singly or in combination of two or more.

(Adhesive polyimide) Next, the resin constituting the adhesive layer 30 is an adhesive thermoplastic polyimide containing tetracarboxylic acid residues and diamine residues (hereinafter, sometimes described as "adhesive The case of "adhesive polyimide") is taken as an example, and a specific configuration example of the adhesive layer 30 will be described. Adhesive polyimide is produced by imidizing the polyimide of the precursor obtained by reacting a specific acid anhydride with a diamine compound. Therefore, the acid anhydride and the diamine compound are explained by Understand specific examples of adhesive polyimides. In addition, in the present invention, the tetracarboxylic acid residue refers to a tetravalent group derived from tetracarboxylic dianhydride, and the diamine residue refers to a divalent group derived from a diamine compound. In addition, the so-called "thermoplastic polyimide" is usually a polyimide whose glass transition temperature (Tg) can be clearly confirmed. In the present invention, it refers to a storage elastic model measured using DMA at 30°C. Polyimide having a number of 1.0×10 ⁸ Pa or more and a storage elastic modulus at 300°C of less than 3.0×10 ⁷ Pa.

(Tetracarboxylic acid residue) The adhesive polyimide preferably contains 90 mol parts or more in total with respect to 100 mol parts of all tetracarboxylic acid residues, which is represented by the following general formula (1) and/or general formula (2) The tetracarboxylic acid residue derived from the tetracarboxylic anhydride (hereinafter, sometimes described as "tetracarboxylic acid residue (1)" and "tetracarboxylic acid residue (2)"). In the present invention, the tetracarboxylic acid residue (1) and/or the tetracarboxylic acid residue (2) are contained in a total of 90 mol parts or more relative to 100 mol parts of all tetracarboxylic acid residues, and It is more preferable to impart solvent solubility to the adhesive polyimide, and it is easy to achieve the coexistence of the flexibility and heat resistance of the adhesive polyimide. If the total of tetracarboxylic acid residues (1) and/or tetracarboxylic acid residues (2) is less than 90 mole parts, the solvent solubility of the adhesive polyimide tends to decrease.

[化4]

In the general formula (1), X represents a single bond or a divalent group selected from the following formulae. In the general formula (2), the cyclic moiety represented by Y represents the formation of a 4-membered ring, a 5-membered ring, and 6 A cyclic saturated hydrocarbon group in a ring, a 7-membered ring or an 8-membered ring.

[化5]

In the formula, Z represents -C ₆ H ₄ -, -(CH ₂ )n- or -CH ₂ -CH(-OC(=O)-CH ₃ )-CH ₂ -, and n represents an integer of 1-20 .

Examples of the tetracarboxylic dianhydride used to derive the tetracarboxylic acid residue (1) include: 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), 3,3', 4,4'-benzophenone tetracarboxylic dianhydride (BTDA), 3,3',4,4'-diphenyl tetracarboxylic dianhydride (DSDA), 4,4'-oxydio Phthalic anhydride (ODPA), 4,4'-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), 2,2-bis[4-(3,4-dicarboxyphenoxy) Phenyl] propane dianhydride (BPADA), p-phenylene bis (trimellitic acid monoester anhydride) (TAHQ), ethylene glycol bis trimellitic anhydride (TMEG), etc.

In addition, examples of the tetracarboxylic dianhydride used to derive the tetracarboxylic acid residue (2) include: 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4- Cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,4,5-cycloheptanetetracarboxylic dianhydride, 1,2,5,6 -Cyclooctane tetracarboxylic dianhydride, etc.

The adhesive polyimide may contain a tetracarboxylic acid residue derived from an acid anhydride other than the tetracarboxylic anhydride represented by the general formula (1) or (2) within a range that does not impair the effect of the invention.

(Diamine residue) Adhesive polyimide is 50 mol parts or more with respect to 100 mol parts of all diamine residues, for example, in the range of 50 mol parts or more and 99 mol parts or less, preferably 80 mol parts or more For example, the dimer acid type diamine residue derived from the dimer acid type diamine is contained in the range of 80 mol parts or more and 99 mol parts or less. By containing the dimer acid-type diamine residue in the above amount, the dielectric properties of the adhesive layer 30 can be improved, and the thermocompression bonding properties can be improved by lowering the glass transition temperature of the adhesive layer 30 and lower Modulus of elasticity is increased to relax internal stress. In addition, by setting the dimer acid-type diamine residue to 50 mole parts or more, solvent solubility and thermoplasticity can be imparted, and the water absorption of the adhesive layer 30 can be reduced, for example, the dimensional change caused by etching can be reduced. If the dimer acid-type diamine residue is less than 50 mol parts with respect to 100 mol parts of all diamine residues, the solvent solubility as an adhesive polyimide decreases.

Here, the so-called dimer acid type diamine means that the two terminal carboxylic acid groups (-COOH) of the dimer acid are substituted with primary aminomethyl (-CH ₂ -NH ₂ ) or amino (-NH ₂ ). Into the diamine. Dimer acid is a known dibasic acid obtained by the intermolecular polymerization of unsaturated fatty acids. Its industrial manufacturing process has been roughly standardized in the industry, and it can be used with clay catalysts and the like for unsaturated carbon numbers of 11-22. Fatty acid is obtained by dimerization. The industrially obtained dimer acid is mainly composed of a 36-carbon dibasic acid obtained by dimerizing an unsaturated fatty acid with a carbon number of 18, such as oleic acid or linoleic acid, and may contain any amount depending on the degree of purification. The amount of monomer acid (carbon number 18), trimer acid (carbon number 54), and other polymerized fatty acids with carbon number 20 to 54. In the present invention, the dimer acid is preferably a compound that increases the content of the dimer acid to 90% by weight or more by molecular distillation. In addition, the double bond remains after the dimerization reaction, but in the present invention, the dimer acid also includes a compound that further undergoes a hydrogenation reaction to reduce the degree of unsaturation.

As a characteristic of the dimer acid-type diamine, polyimine can be imparted with characteristics derived from a dimer acid skeleton. That is, the dimer acid type diamine is aliphatic with a huge molecule with a molecular weight of about 560 to 620. Therefore, the molar volume of the molecule can be increased and the polar group of the polyimine can be relatively reduced. It is believed that the characteristics of such dimer acid-type diamines contribute to suppressing the decrease in the heat resistance of polyimine and reducing the dielectric constant and the dielectric loss tangent to improve the dielectric properties. In addition, it contains two freely movable hydrophobic chains with 7-9 carbons and two chain aliphatic amino groups with a length close to 18 carbons. Therefore, it not only imparts flexibility to polyimide, but also Since polyimine has an asymmetric chemical structure or a non-planar chemical structure, it is considered that the low dielectric constant and low dielectric loss tangent of polyimine can be achieved.

Commercial products of dimer acid type diamines are available, such as: PRIAMINE 1073 (trade name) manufactured by CRODA Japan, and generalized products manufactured by CRODA Japan. PRIAMINE 1074 (trade name), PRIAMINE 1075 (trade name) manufactured by CRODA Japan, Versamine 551 manufactured by BASF Japan (Trade name), Versamine 552 (trade name) manufactured by BASF Japan, etc.

In addition, the adhesive polyimide is preferably contained in a range of 1 mol part or more and 50 mol parts or less in total with respect to 100 mol parts of all diamine residues. It is selected from the following general formula (B1 )-The diamine residue derived from at least one diamine compound in the diamine compound represented by general formula (B7) is more preferably contained in the range of 1 mol part or more and 20 mol part or less. The diamine compound represented by general formula (B1) to general formula (B7) contains a flexible molecular structure. Therefore, by using at least one diamine compound selected from these in an amount within the above range, the poly The flexibility of the imine molecular chain imparts solvent solubility and thermoplasticity. In addition, by using the diamine compound represented by the general formula (B1) to the general formula (B7), for example, even when a via hole (through hole) is formed in the adhesive layer 30 by laser processing By increasing the proportion of aromatic rings in the polyimide molecular structure, for example, the absorption in the ultraviolet region can be improved. In addition, the glass transition temperature of the adhesive layer 30 can be increased, thereby increasing the The heat resistance in terms of the temperature rise of the bottom metal due to the incidence of laser light can further improve the laser processability. If the total amount of diamine residues derived from at least one diamine compound selected from the diamine compounds represented by the following general formulas (B1) to (B7) is relative to 100 moles of all diamine residues If the part exceeds 50 mole parts, the flexibility of the adhesive polyimide is insufficient, and the glass transition temperature rises. Therefore, the residual stress due to thermocompression bonding increases and the dimensional change rate after etching tends to deteriorate.

[化6]

In formulas (B1) to (B7), R ₁ independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, and the linking group A independently represents a group selected from -O-, -S-, -CO-, The divalent group in -SO-, -SO ₂ -, -COO-, -CH ₂ -, -C(CH ₃ ) ₂ -, -NH- or -CONH-, n ₁ independently represents an integer from 0 to 4 . Among them, the part that overlaps with formula (B2) is removed from formula (B3), and the part that overlaps with formula (B4) is removed from formula (B5). Furthermore, the term "independently" means that in one or two or more of the above formulas (B1) to (B7), multiple linking groups A, multiple R ₁ or multiple n ₁ may be Same or different. In addition, in formulas (B1) to (B7), the hydrogen atoms in the two terminal amino groups may be substituted, for example, -NR ₂ R ₃ (here, R ₂ and R ₃ independently refer to alkyl groups, etc. Optional substituents).

The diamine represented by the formula (B1) (hereinafter, sometimes referred to as "diamine (B1)") is an aromatic diamine having two benzene rings. It is believed that the diamine (B1) is located in the meta position with the divalent linking group A through the amino group directly bonded to at least one benzene ring, and the polyimide molecular chain has an increased degree of freedom and high flexibility, This contributes to the improvement of the flexibility of the polyimide molecular chain. Therefore, by using diamine (B1), the thermoplasticity of polyimide improves. Here, the linking group A is preferably -O-, -CH ₂ -, -C(CH ₃ ) ₂ -, -CO-, -SO ₂ -, -S-, -COO-.

As diamine (B1), for example, 3,3'-diaminodiphenylmethane, 3,3'-diaminodiphenylpropane, 3,3'-diaminodiphenyl sulfide, 3, 3'-Diaminodiphenyl sulfide, 3,3-Diaminodiphenyl ether, 3,4'-Diaminodiphenyl ether, 3,4'-Diaminodiphenylmethane, 3,4'- Diaminodiphenylpropane, 3,4'-diaminodiphenyl sulfide, 3,3'-diaminobenzophenone, (3,3'-bisamino)diphenylamine, etc.

The diamine represented by the formula (B2) (hereinafter, sometimes described as "diamine (B2)") is an aromatic diamine having three benzene rings. It is believed that the diamine (B2) is located in the meta position with the divalent linking group A through the amino group directly bonded to at least one benzene ring, and the polyimide molecular chain has an increased degree of freedom and high flexibility, This contributes to the improvement of the flexibility of the polyimide molecular chain. Therefore, by using diamine (B2), the thermoplasticity of polyimide is improved. Here, the linking group A is preferably -O-.

As the diamine (B2), for example, 1,4-bis(3-aminophenoxy)benzene, 3-[4-(4-aminophenoxy)phenoxy]aniline, 3-[3- (4-Aminophenoxy)phenoxy]aniline and the like.

The diamine represented by the formula (B3) (hereinafter, sometimes described as “diamine (B3)”) is an aromatic diamine having three benzene rings. It is believed that the diamine (B3) is located in the meta position with each other through two divalent linking groups A directly bonded to a benzene ring, and the polyimide molecular chain has an increased degree of freedom and high flexibility, This contributes to the improvement of the flexibility of the polyimide molecular chain. Therefore, by using diamine (B3), the thermoplasticity of polyimide improves. Here, the linking group A is preferably -O-.

As the diamine (B3), for example, 1,3-bis(4-aminophenoxy)benzene (TPE-R), 1,3-bis(3-aminophenoxy)benzene (APB), 4 ,4'-[2-Methyl-(1,3-phenylene)bisoxy]bisaniline, 4,4'-[4-methyl-(1,3-phenylene)bisoxy] Dianiline, 4,4'-[5-methyl-(1,3-phenylene) bisoxy] bisaniline, etc.

The diamine represented by the formula (B4) (hereinafter, sometimes referred to as “diamine (B4)”) is an aromatic diamine having four benzene rings. It is believed that the diamine (B4) has high flexibility through the amino group directly bonded to at least one benzene ring and the divalent linking group A in the meta position, thereby contributing to the flexibility of the polyimide molecular chain improve. Therefore, by using diamine (B4), the thermoplasticity of polyimide is improved. Here, the linking group A is preferably -O-, -CH ₂ -, -C(CH ₃ ) ₂ -, -SO ₂ -, -CO-, -CONH-.

As the diamine (B4), bis[4-(3-aminophenoxy)phenyl]methane, bis[4-(3-aminophenoxy)phenyl]propane, bis[4-(3 -Aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)phenyl]sulfonate, bis[4-(3-aminophenoxy)]benzophenone, bis[4, 4'-(3-aminophenoxy)]benzaniline and the like.

The diamine represented by the formula (B5) (hereinafter, sometimes referred to as "diamine (B5)") is an aromatic diamine having four benzene rings. It is believed that the diamine (B5) is located in the meta position with each other through two divalent linking groups A directly bonded to at least one benzene ring, while the polyimide molecular chain has an increased degree of freedom and high flexibility , Thereby contributing to the improvement of the flexibility of the polyimide molecular chain. Therefore, by using diamine (B5), the thermoplasticity of polyimide is improved. Here, the linking group A is preferably -O-.

Examples of the diamine (B5) include 4-[3-[4-(4-aminophenoxy)phenoxy]phenoxy]aniline, 4,4'-[oxybis(3,1-a Phenyloxy)] bisaniline and the like.

The diamine represented by the formula (B6) (hereinafter, sometimes referred to as "diamine (B6)") is an aromatic diamine having four benzene rings. It is thought that the diamine (B6) has high flexibility by having at least two ether bonds, thereby contributing to the improvement of the flexibility of the polyimide molecular chain. Therefore, by using diamine (B6), the thermoplasticity of polyimide is improved. Here, as the linking group A, -C(CH ₃ ) ₂ -, -O-, -SO ₂ -, -CO- are preferable.

As the diamine (B6), for example, 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP), bis[4-(4-aminophenoxy)phenyl] Ether (BAPE), bis[4-(4-aminophenoxy)phenyl] sulfide (BAPS), bis[4-(4-aminophenoxy)phenyl] ketone (BAPK), etc.

The diamine represented by the formula (B7) (hereinafter, may be described as "diamine (B7)") is an aromatic diamine having four benzene rings. It is considered that the diamine (B7) has a highly flexible divalent linking group A on both sides of the diphenyl skeleton, and therefore contributes to the improvement of the flexibility of the polyimide molecular chain. Therefore, by using diamine (B7), the thermoplasticity of polyimine is improved. Here, the linking group A is preferably -O-.

Examples of diamine (B7) include bis[4-(3-aminophenoxy)]biphenyl, bis[4-(4-aminophenoxy)]biphenyl, and the like.

The adhesive polyimide may include a diamine residue derived from the dimer acid-type diamine and diamine compounds other than the diamine (B1) to the diamine (B7) within a range that does not impair the effect of the invention.

In addition, regarding the adhesive polyimide, by selecting the types of the tetracarboxylic acid residues and diamine residues, or the respective mols when two or more tetracarboxylic acid residues or diamine residues are contained Ratio, can control thermal expansion coefficient, tensile elastic modulus, glass transition temperature, etc. In addition, in the case of having a plurality of polyimide structural units, they may exist in the form of blocks, or may exist randomly, and preferably exist randomly.

The concentration of the imine group of the adhesive polyimide is preferably 20% by weight or less. Here, the "imine group concentration" refers to the value obtained by dividing the molecular weight of the polyimine group (-(CO) ₂ -N-) by the molecular weight of the entire structure of the polyimide . If the concentration of the imine group exceeds 20% by weight, the molecular weight of the resin itself becomes small, and the low hygroscopicity also deteriorates due to the increase of the polar group, and the elastic modulus increases.

The weight average molecular weight of the adhesive polyimide is, for example, preferably in the range of 10,000 to 400,000, and more preferably in the range of 20,000 to 350,000. If the weight average molecular weight is less than 10,000, the strength of the adhesive layer 30 decreases and there is a tendency for it to become brittle. On the other hand, if the weight average molecular weight exceeds 400,000, the viscosity increases excessively, and defects such as uneven thickness of the adhesive layer 30 and streaks tend to occur during the coating operation.

When the adhesive polyimide is formed into a multilayer circuit board, it covers the conductor circuit layer of an arbitrary circuit board. Therefore, in order to suppress the diffusion of copper, it is most preferably a structure that has been completely imidized. Among them, a part of the polyimide may be amide acid. Regarding the imidization rate, it is possible to use a Fourier transform infrared spectrophotometer (commercial product: FT/IR620 manufactured by JASCO Corporation) and use the primary reflection ATR (Attenuated Total Reflectance) method The infrared absorption spectrum of the polyimide film was measured, and it was calculated based on the absorbance of the C=O stretching and contraction derived from the amide group at 1780 cm ^-1 based on the benzene ring absorber in the vicinity of 1015 cm ^-1 .

(Crosslink formation) When the adhesive polyimide has a ketone group, the ketone group reacts with the amino group of an amino compound having at least two primary amino groups as functional groups to form a C=N bond, thereby forming a crosslink structure. By forming a cross-linked structure, the heat resistance of the adhesive polyimide can be improved. Examples of preferred tetracarboxylic anhydrides for forming polyimides having ketone groups include 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA), and examples of preferred diamine compounds include 4,4'-bis(3-aminophenoxy)benzophenone (BABP), 1,3-bis[4-(3-aminophenoxy)benzyl]benzene (BABB) and other aromatics Diamine.

Examples of the amino compound that can be used in the crosslinking formation of the adhesive polyimide include dihydrazine compounds, aromatic diamines, and aliphatic amines. Among these, dihydrazine compounds are preferred. Aliphatic amines other than the dihydrazine compound tend to form a crosslinked structure even at room temperature, and there is a concern about the storage stability of the varnish. On the other hand, the aromatic diamine needs to be set to a high temperature in order to form a crosslinked structure. When the dihydrazine compound is used, the storage stability of the varnish and the shortening of the curing time can be coexisted. As the dihydrazine compound, for example, dihydrazine oxalate, dihydrazine malonate, dihydrazine succinate, dihydrazine glutarate, dihydrazine adipate, dihydrazine pimelate, Dihydrazine suberate, dihydrazine azelate, dihydrazine sebacate, dihydrazine dodecanedioate, dihydrazine maleate, dihydrazine fumarate, diglycolic acid dihydrazide Hydrazine, dihydrazine tartrate, dihydrazine malate, dihydrazine phthalate, dihydrazine isophthalate, dihydrazine terephthalate, dihydrazine 2,6-naphthoate, 4,4 -Diphenyl dihydrazine, 1,4-naphthoic acid dihydrazine, 2,6-pyridine diacid dihydrazine, itaconic acid dihydrazine and other dihydrazine compounds. The above dihydrazine compounds may be used alone or in combination of two or more kinds.

Adhesive polyimide can be produced by reacting the tetracarboxylic dianhydride and diamine compound in a solvent to generate polyimide and then heating the ring to close it. For example, the tetracarboxylic dianhydride and the diamine compound are dissolved in an organic solvent at approximately equal moles and stirred at a temperature in the range of 0°C to 100°C for 30 minutes to 24 hours to carry out the polymerization reaction, thereby obtaining Polyamide as the precursor of adhesive polyimide. During the reaction, the reaction component is dissolved so that the generated precursor is in the range of 5 wt% to 50 wt% in the organic solvent, preferably in the range of 10 wt% to 40 wt%. As the organic solvent used in the polymerization reaction, for example, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N,N-diethylacetamide (DMAc) Amine, N-methyl-2-pyrrolidone (NMP), 2-butanone, dimethyl sulfide (DMSO), hexamethylphosphatidamide, N-methylcaprolactam, dimethyl sulfate, cyclic Hexanone, dioxane, tetrahydrofuran, diethylene glycol dimethyl ether (diglyme), triglyme (triglyme), cresol, etc. These solvents may be used in combination of two or more types, and aromatic hydrocarbons such as xylene and toluene may be used in combination. In addition, the usage amount of such an organic solvent is not particularly limited, but it is preferably adjusted to a usage amount such that the concentration of the polyamide acid solution obtained by the polymerization reaction is about 5% to 50% by weight.

The synthesized polyamide acid is generally advantageously used as a reaction solvent solution, and can be concentrated, diluted or replaced with other organic solvents as necessary. In addition, polyamide acid is generally used advantageously because of its excellent solvent solubility. The viscosity of the polyamide acid solution is preferably in the range of 500 cps to 100,000 cps. If it deviates from the above range, defects such as thickness unevenness and streaks are likely to occur in the film during coating work using a coater or the like.

There is no particular limitation on the method of forming polyimide by the imidization of polyamide. For example, it can be carried out in the above-mentioned solvent under temperature conditions in the range of 80°C to 400°C for 1 hour to 24 hours. Heat treatment such as heating.

When the adhesive polyimide obtained as above is crosslinked and formed, the amino compound is added to the resin solution containing the polyimide having a ketone group, and the adhesive polyimide The ketone group and the primary amino group of the amino compound undergo condensation reaction. Through the condensation reaction, the resin solution hardens to become a hardened product. In this case, the amount of the amino compound added may be 0.004 mol to 1.5 mol in total, preferably 0.005 mol to 1.2 mol, more preferably 0.03 mol, based on 1 mol of the ketone group. The amino compound is added in a manner of -0.9 mol, and most preferably 0.04 mol to 0.5 mol. Regarding the addition amount of the amino compound whose primary amino group is less than 0.004 mol in total with respect to 1 mol of the ketone group, the crosslinking of the polyimide chain using the amino compound is insufficient, so there is a hardened adhesive layer In 30, the heat resistance tends to be hardly expressed. If the addition amount of the amino compound exceeds 1.5 mol, the unreacted amino compound functions as a thermoplastic agent, and the heat resistance of the adhesive layer 30 tends to decrease.

The conditions for the condensation reaction for cross-linking are not special if the ketone group in the adhesive polyimine reacts with the primary amino group of the amino compound to form an imine bond (C=N bond). limit. Regarding the temperature of the heating condensation, the reason is that the water produced by the condensation is released to the outside of the system, or the condensation step is simplified in the case of the heating condensation reaction after the synthesis of the adhesive polyimide, etc. For example, it is preferably in the range of 120°C to 220°C, and more preferably in the range of 140°C to 200°C. The reaction time is preferably about 30 minutes to 24 hours. The end point of the reaction can be measured, for example, by using a Fourier transform infrared spectrophotometer (commercial product: FT/IR620 manufactured by JASCO Corporation) to measure the infrared absorption spectrum using 1670 cm ^-1 It was confirmed that the nearby absorption peak derived from the ketone group in the polyimide resin decreased or disappeared, and the absorption peak derived from the imine group near 1635 cm ^-1 appeared.

The heating condensation of the ketone group of the adhesive polyimide and the primary amino group of the amino compound can be carried out, for example, by the following method: (a) The amino group is added immediately after the synthesis of the adhesive polyimide (imination) (B) Preliminarily put an excessive amount of amino compound as a diamine component, followed by the synthesis of adhesive polyimide (imidization), and it does not participate in the imidization or hydration A method of heating the aminated residual amino compound and the adhesive polyimide together; or (c) after processing the adhesive polyimide composition with the amino compound added into a predetermined shape (for example, A method of heating after coating on any substrate or after forming into a film.

In order to impart heat resistance to the adhesive layer 30, the formation of an imine bond was described in the formation of a cross-linked structure in the adhesive polyimide, but it is not limited to this, as a curing method of the adhesive layer 30 For example, epoxy resin, epoxy resin hardener, etc. can also be formulated for hardening.

＜Thickness of resin layer＞ Regarding the metal-clad laminate 100, when the total thickness of the thickness T3 of the insulating resin layer 10 and the thickness T2 of the adhesive layer 30 is set to T1, the total thickness T1 is in the range of 50 μm to 250 μm, preferably 70 Within the range of μm～150 μm. If the total thickness T1 is less than 50 μm, the effect of reducing the transmission loss when manufacturing a multilayer circuit board using the metal-clad laminate 100 is insufficient, and if it exceeds 250 μm, there is a concern that productivity may decrease.

In addition, the thickness T2 of the adhesive layer 30 is preferably in the range of 20 μm to 200 μm, and more preferably in the range of 20 μm to 100 μm, for example. If the thickness T2 of the adhesive layer 30 is less than the lower limit, the transmission loss of the high-frequency substrate may increase. On the other hand, if the thickness T2 of the adhesive layer 30 exceeds the upper limit, problems such as a decrease in dimensional stability may occur.

In addition, the ratio (T2/T1) of the thickness T2 of the adhesive layer 30 to the total thickness T1 is in the range of 0.5 to 0.8, and preferably in the range of 0.5 to 0.7. If the ratio (T2/T1) is less than 0.5, it is difficult to make the total thickness T1 50 μm or more, and if it exceeds 0.8, disadvantages such as reduced dimensional stability may occur.

The thickness T3 of the insulating resin layer 10 is, for example, preferably in the range of 12 μm to 100 μm, and more preferably in the range of 12 μm to 50 μm. If the thickness T3 of the insulating resin layer 10 is less than the lower limit, problems such as warpage of the metal-clad laminate 100 may occur. If the thickness T3 of the insulating resin layer 10 exceeds the upper limit, defects such as a decrease in productivity will occur.

In the metal-clad laminate 100 of the present embodiment, in order to achieve a low dielectric loss tangent of the entire resin layer and to be able to cope with high-frequency transmission, the thickness T2 of the adhesive layer 30 itself is increased. However, in general, a material with a low elastic modulus shows a high coefficient of thermal expansion, and therefore, an increase in layer thickness may lead to a decrease in dimensional stability. Here, it is considered that the dimensional change that occurs when the metal-clad laminate 100 is circuit-processed and multi-layer circuitized is mainly caused by the following mechanisms a) to c). The total amount of b) and c) is the result after etching. The size changes. a) When manufacturing the metal-clad laminate 100, internal stress is accumulated in the resin layer. b) During circuit processing, the metal layer 20 is etched to release the internal stress accumulated in a), and the resin layer expands or contracts. c) During circuit processing, by etching the metal layer 20, the exposed resin absorbs moisture and expands.

The main causes of the internal stress in a) are: 1) the difference in the thermal expansion coefficient between the metal layer 20 and the resin layer; 2) the internal strain of the resin generated by filming. Here, the magnitude of the internal stress caused by 1) is not only affected by the difference in thermal expansion coefficient, but also by the temperature difference ΔT from the bonding temperature (heating temperature) to the cooling solidification temperature during multilayer circuitization. That is, the internal stress becomes larger in proportion to the temperature difference ΔT. Therefore, even if the difference in thermal expansion coefficient between the metal layer 20 and the resin layer is small, the higher the resin that requires high temperature for bonding, the larger the internal stress. In the metal-clad laminate 100 of this embodiment, by adopting the adhesive layer 30 that satisfies the above-mentioned conditions (i) to (iii), internal stress is reduced and dimensional stability is ensured. In addition, since the adhesive layer 30 is laminated on the insulating resin layer 10, when a multilayer circuit board is formed, it functions as an intermediate layer and suppresses warpage and dimensional changes.

[Method of manufacturing metal-clad laminate] The metal-clad laminate 100 can be manufactured by the following method 1 or method 2, for example. [method 1] The resin composition used as the adhesive layer 30 is formed into a film shape and made into an adhesive film, and the adhesive film is arranged and bonded so as to face the insulating resin layer 10 of the single-sided metal-clad laminate 40, and Method of thermal compression. [Method 2] A method of applying a solution of the resin composition to be the adhesive layer 30 on the insulating resin layer 10 of the single-sided metal-clad laminate 40 with a predetermined thickness and drying. In this case, treatments such as heating for the curing reaction or the crosslinking reaction may be performed as necessary.

The adhesive film used in the method 1 can be manufactured by, for example, applying a solution of the resin composition that becomes the adhesive layer 30 to an arbitrary supporting substrate and drying, and then peeling from the supporting substrate. As the adhesive film, an adhesive polyimide film formed by forming the adhesive polyimide into a film shape can also be used. As a form of the manufacturing method of the adhesive polyimide film, for example, the following method can be cited: [1] A solution of polyamide acid is applied to a supporting substrate and dried, heat-treated to be imidized, and then A method of manufacturing an adhesive film by peeling a supporting substrate; [2] A solution of polyamic acid is applied to the supporting substrate and dried, and then the gel film of polyamic acid is peeled off from the supporting substrate and subjected to heat treatment. A method of manufacturing an adhesive film by imidization; [3] A method of manufacturing an adhesive film by peeling off the self-supporting substrate after coating a solution of adhesive polyimide on a supporting substrate and drying. Among the above [1] to [3], it is preferable to use a solution of [3] that is coated with a solution of adhesive polyimide in a polyamide acid solution to complete imidization on a support substrate and dried. Method to form. Since the adhesive polyimide is solvent-soluble, it is advantageous to imidize the polyamide acid in a solution state and directly use it as a coating solution for the adhesive polyimide. In addition, the adhesive polyimide constituting the adhesive film can also be formed by cross-linking by the above-mentioned method.

In the above method 1 and method 2, there is no particular limitation as to the method of applying the solution of the resin composition to be the adhesive layer 30 on the support substrate or the insulating resin layer 10, and for example, a missing angle wheel or a mold can be used. , Doctor blade, die lip and other coating machines for coating. In the forming step of the adhesive layer 30, it is preferable to form the surface of the formed adhesive layer 30 into a flat shape. In addition, it is preferable that the thickness of the adhesive layer 30 is also uniformly formed. By forming the surface of the adhesive layer 30 into a flat shape and making the thickness uniform, the adhesiveness in the manufacturing process of the multilayer circuit board is improved.

The metal-clad laminate 100 of the present embodiment obtained as described above can be manufactured by performing wiring circuit processing on the metal layer 20 to produce a single-sided FPC or a double-sided FPC. In addition, the adhesiveness of the adhesive layer 30 or the use of By stacking multiple single-sided FPC or double-sided FPC with arbitrary bonding sheets, etc., a multilayer circuit board can be manufactured.

[Circuit Board] Fig. 2 is a cross-sectional view showing the structure of a circuit board according to an embodiment of the present invention. The circuit substrate 101 includes an insulating resin layer 10; a conductive circuit layer 50 laminated on one side of the insulating resin layer 10; and an adhesive layer 30 laminated on the other side of the insulating resin layer 10. That is, the circuit board 101 has a structure in which a conductive circuit layer 50/insulating resin layer 10/adhesive layer 30 are laminated in this order. The circuit board 101 of this embodiment is obtained by performing wiring circuit processing on the metal layer 20 of the metal-clad laminate 100.

(Conductor circuit layer) The conductive circuit layer 50 is a layer in which a conductive circuit is formed in a predetermined pattern on one side of the insulating resin layer 10. For example, a photosensitive resist is coated on the metal layer 20 of the metal-clad laminate 100, exposed and developed to form a predetermined photomask pattern, and after the metal layer 20 is etched through the photomask pattern, the photomask pattern is removed Thus, the conductor circuit layer 50 of a predetermined pattern can be formed. In addition, the "conductor circuit layer" refers to the in-plane connection electrode (land electrode) formed in the surface direction of the insulating resin layer 10 and the interlayer connection electrode (via electrode). the difference.

Regarding the conductor circuit layer 50, from the viewpoint of reducing transmission loss in high-frequency transmission, the maximum height roughness (Rz) of the surface in contact with the insulating resin layer 10 is preferably 1.0 μm or less. The transmission loss includes the sum of the conductor loss and the dielectric loss. If the Rz of the conductor circuit layer 50 is large, the conductor loss will increase and the transmission loss will be adversely affected. Therefore, it is preferable to control Rz.

The structure of the insulating resin layer 10 and the adhesive layer 30 in the circuit board 101 of this embodiment is as explained in the metal-clad laminate 100.

[Multilayer Circuit Board] Next, referring to FIGS. 3 to 6, a multilayer circuit board according to an embodiment of the present invention will be described. Generally, the multilayer circuit board has a laminate including a plurality of insulating resin layers, and two or more conductor circuit layers embedded in the laminate, and preferably has at least two or more insulating resin layers and at least two Layer above the conductor circuit layer. Here, regarding the multilayer circuit board, two preferred embodiments will be described. The multilayer circuit board 200 and the multilayer circuit board 201 of this embodiment include at least one of the above-mentioned circuit boards 101. In addition, the multilayer circuit board 200 and the multilayer circuit board 201 of the present embodiment may include any circuit board other than the circuit board 101 laminated on the circuit board 101.

<The first embodiment> 3 is a cross-sectional view in the stacking direction showing the structure of the multilayer circuit board 200 according to the first embodiment of the present invention. The multilayer circuit board 200 of the first embodiment has a structure in which a plurality of circuit boards 101 and an arbitrary circuit board 110 are stacked in the same direction. That is, from top to bottom in FIG. 3, the adhesive layer 30 of the first circuit board 101 is connected and laminated so as to cover the conductor circuit layer 50 of the second circuit board 101, and further, the second circuit board 101 The adhesive layer 30 of φ is connected and laminated so as to cover the conductor circuit layer 50 of any circuit board 110 that does not have the adhesive layer 30. Here, the structure or material of any circuit substrate 110 is not limited. For example, the conductive circuit layer 50 may be formed of a patterned metal layer 20, or may have a damascene structure. In addition, the conductor circuit layer 50 of any circuit board 110 can be formed on the insulating resin layer 10 by inkjet, sputtering, plating, or the like. Furthermore, the thickness, material, physical properties, etc. of the conductive circuit layer 50 or the insulating resin layer 10 of the arbitrary circuit board 110 are also not particularly limited.

In FIG. 3, a laminated structure of two circuit boards 101 and one arbitrary circuit board 110 is shown, and three or more circuit boards 101 may be laminated. In addition, the adhesive layer 30 may cover the entire conductor circuit layer 50 of the adjacent circuit board 101 or any circuit board 110, or may cover a part of it. Furthermore, in the multilayer circuit board 200, the conductive circuit layer 50 is exposed on the surface of the uppermost circuit board 101, and an arbitrary protective film covering the uppermost conductive circuit layer 50 may be provided. In addition, in FIG. 3, as an arbitrary circuit board 110, a case where the conductor circuit layer 50 is formed on one side of the insulating resin layer 10 is illustrated. The conductor circuit layer 50 may be formed on both sides of the insulating resin layer 10.

4 is a manufacturing process diagram of the multilayer circuit board 200 of the first embodiment. First, a plurality of circuit boards 101 and arbitrary circuit boards 110 are prepared. Furthermore, the adhesive layer 30 of the first circuit substrate 101 is arranged so as to overlap with the conductor circuit layer 50 of the second circuit substrate 101, and the adhesive layer 30 of the second circuit substrate 101 is not The conductive circuit layer 50 of the arbitrary circuit board 110 of the adhesive layer 30 is overlapped and arrange|positioned so that it may oppose, and these are crimped together, and it can manufacture (crimping process). In addition, FIG. 4 shows an example in which two circuit boards 101 are laminated, but three or more circuit boards 101 may be laminated at a time. In addition, the arbitrary circuit board 110 is not limited to one, and multiple layers may be laminated.

Since the adhesive layer 30 of the circuit substrate 101 is flattened on its surface, no voids or the like are generated in the adhesive layer 30 during the crimping step, and the adhesive resin can be filled between the conductor circuits of the conductor circuit layer 50 Laminate under the state. In addition, if necessary, the multilayer circuit board 200 obtained by stacking is pressed from both sides with a pressing roller, a pressing device, or the like, so that a thickness adjustment step of adjusting the thickness of the adhesive layer 30 may also be performed. Through the thickness adjustment step, the thickness accuracy of the entire adhesive layer 30 and the multilayer circuit substrate 200 can be improved. Furthermore, at the time of pressure bonding, for example, a heat treatment of heating at a temperature of 60°C to 220°C may be performed. Thereby, a multilayer circuit board 200 in which a plurality of circuit boards are integrally laminated can be manufactured. During the heat treatment, in the adhesive layer 30, for example, the adhesive polyimide may be heated and condensed to form a crosslinked structure of imine bonds.

In this embodiment, the adhesive layer 30 of each circuit board 101 has a function as an adhesive sheet for bonding the circuit boards to each other, and a function as a protective film for protecting the conductor circuit. Therefore, it is not necessary to separately prepare a bonding sheet or a protective layer for a conductive circuit and to intervene between the circuit substrates, so that the simplification of the manufacturing process and equipment for forming the multilayer circuit, the simplification of materials, and the cost reduction can be realized.

The multilayer circuit board 200 obtained as described above includes a configuration in which an adhesive layer 30 having a sufficient thickness is provided between the conductive circuit layer 50 and the insulating resin layer 10 to ensure insulation, flexibility, and low dielectric properties. Furthermore, in the multilayer circuit board 200 of the present embodiment, if necessary, a layer such as a cover film or a solder resist may be provided as a protective layer. In addition, although illustration is omitted, chip-type electronic components such as IC chips, chip capacitors, chip coils, and chip resistors may be built in the multilayer circuit board 200 of this embodiment. In addition, in the multilayer circuit board 200 of this embodiment, interlayer connection electrodes (via electrodes) not shown may be formed. The interlayer connection electrode can be formed by forming a via hole in the insulating resin layer 10 by laser processing or drilling processing, and then filling it with a conductive paste by printing or the like. As the conductive paste, for example, a conductive paste obtained by mixing an organic solvent, an epoxy resin, or the like with a conductive powder containing tin as a main component can be used. In addition, the interlayer connection electrode may form a plated portion on the inner surface of the via hole and a part of the surface of the conductive circuit layer 50 after the via hole is formed.

<The second embodiment> 5 is a cross-sectional view in the stacking direction showing the structure of the multilayer circuit board 201 according to the second embodiment of the present invention. In the multilayer circuit board 201 of the second embodiment, a structure in which a pair of circuit boards 101 are bonded such that these adhesive layers 30 face each other is set as one circuit board unit 102, and includes at least one述circuit board unit 102. That is, from top to bottom in FIG. 5, the first metal-clad laminate 100, the circuit board unit 102, and the second metal-clad laminate 100 are sequentially arranged (wherein, the first metal-clad laminate 100 is opposite Direction), and laminated in the form of sandwiching the circuit board unit 102 between the adhesive layers 30 of two metal-clad laminated boards 100. The adhesive layer 30 of the first metal-clad laminate 100 is laminated so as to be in contact with the conductor circuit layer 50 on the single side (upper side in the figure) of the circuit board unit 102, and further, on the other side of the circuit board unit 102 The conductive circuit layer 50 on the single side (the lower side in the figure) and the adhesive layer 30 of the second metal-clad laminate 100 are laminated so as to be in contact with the conductive circuit layer 50. Furthermore, in FIG. 5, a laminated structure including only one circuit board unit 102 is shown, and it can also be made to include a plurality of circuit board units 102 by interposing an adhesive sheet or circuit board 101 or any circuit board 110. The layered structure. In addition, as one or both of the two upper and lower metal-clad laminates 100, the circuit board 101 can also be used.

FIG. 6 is a manufacturing process diagram of the multilayer circuit board 201 of the second embodiment. First, one circuit board unit 102 and two metal-clad laminated boards 100 are prepared. Here, the circuit substrate unit 102 can be manufactured by preparing a pair of circuit substrates 101 and bonding the adhesive layer 30 of one circuit substrate 101 and the adhesive layer 30 of the other circuit substrate 101 together. Furthermore, the multilayer circuit board 201 can be manufactured by the following method: the adhesive layer 30 of the first metal-clad laminate 100 is arranged so as to face the conductor circuit layer 50 on the upper surface side of the circuit board unit 102, and further, on the circuit board The conductive circuit layer 50 on the lower surface side of the cell 102 and the adhesive layer 30 of the second metal-clad laminated board 100 are arranged so as to face the conductive circuit layer 50, and these are crimped together (crimping step).

Furthermore, the circuit board unit 102 may not be produced, but the adhesive layer 30 of the first metal-clad laminate 100 is arranged so as to face the conductor circuit layer 50 of the upper circuit board 101, and the adhesive layer of the upper circuit board 101 The bonding layer 30 and the bonding layer 30 of the lower circuit board 101 are arranged to face each other, and further, on the conductive circuit layer 50 of the lower circuit board 101, the bonding layer 30 of the second metal-clad laminate 100 is opposite to The conductor circuit layers 50 are arranged so as to face each other, and these are all crimped together.

If necessary, the multilayer circuit board 201 obtained by stacking is pressed from both sides using a pressing roller, a pressing device, or the like, and thereby the thickness adjustment step of adjusting the thickness of the adhesive layer 30 may also be performed. Through the thickness adjustment step, the thickness accuracy of the entire adhesive layer 30 and the multilayer circuit substrate 201 can be improved. Furthermore, at the time of pressure bonding, for example, a heat treatment of heating at a temperature of 60°C to 220°C may be performed. Thereby, a multilayer circuit board 201 in which a plurality of circuit boards are integrally laminated can be manufactured. During the heat treatment, in the adhesive layer 30, for example, the adhesive polyimide may be heated and condensed to form a crosslinked structure of imine bonds.

In this embodiment, the adhesive layer 30 of each circuit board 101 also has a function as an adhesive sheet for bonding the circuit boards to each other. Therefore, there is no need to separately prepare the bonding sheet and make it exist between the circuit substrates. The simplification of the manufacturing process and equipment for forming the multilayer circuit, the simplification of materials, and the cost reduction can be realized.

The other structures and effects of the multilayer circuit board 201 of this embodiment are the same as those of the multilayer circuit board 200 of the first embodiment. [Example]

Examples are shown below, and the features of the present invention will be described 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.

[Measurement of dimensional change rate] The measurement of the dimensional change rate is performed in the following procedure. First, a test piece of 150 mm square was used to expose and develop the dry film resist at intervals of 100 mm, thereby forming a target for position measurement. In an environment with a temperature of 23±2°C and a relative humidity of 50±5%, the size before etching (normal) is measured, and then the copper outside the target of the test piece is removed by etching (liquid temperature below 40°C, time within 10 minutes) . After standing for 24±4 hours in an environment with a temperature of 23±2°C and a relative humidity of 50±5%, the size after etching was measured. The dimensional change rate from the normal state of each of the three locations in the MD direction (long side direction) and TD direction (width direction) was calculated, and the average value of each was used as the dimensional change rate after etching. The dimensional change rate after etching is calculated by the following formula.

Dimensional change rate after etching (%)=(B-A)/A×100 A: Distance between targets before etching B: Distance between targets after etching

Next, this test piece was heat-treated in an oven at 250°C for 1 hour, and the distance between the subsequent position targets was measured. The dimensional change rate after etching was calculated for each of three locations in the MD direction (long side direction) and TD direction (width direction), and the average value of each was used as the dimensional change rate after the heat treatment. The heating dimensional change rate is calculated by the following formula.

Dimensional change rate after heating (%)=(C-B)/B×100 B: Distance between targets after etching C: Distance between targets after heating

[Determination of viscosity] An E-type viscometer (manufactured by Brookfield, trade name: DV-II+Pro) was used to measure the viscosity at 25°C. Set the number of revolutions with a torque of 10% to 90%, and read the value when the viscosity is stable 2 minutes after the start of the measurement.

[Determination of Coefficient of Thermal Expansion (CTE)] Use a thermomechanical analyzer (manufactured by Bruker, trade name: 4000SA) on a 3 mm×20 mm polyimide film with a size of 3 mm×20 mm, and apply a load of 5.0 g from 30°C at a constant heating rate The temperature was raised to 300°C, and the temperature was maintained at the temperature for 10 minutes, and then cooled at a rate of 5°C/min. The average thermal expansion coefficient (thermal expansion coefficient) from 250°C to 100°C was determined.

[Measurement of storage elastic modulus and glass transition temperature (Tg)] A dynamic viscoelasticity measuring device (DMA: manufactured by UBM Corporation, trade name: E4000F) is used for a resin sheet with a size of 5 mm×20 mm, and the temperature rise rate from 30°C to 400°C is 4°C/min and the frequency is 11 Hz. Measure under the conditions. In addition, the temperature at which the change in elastic modulus (tan δ) is the largest is defined as the glass transition temperature.

[Measurement of dielectric constant and dielectric loss tangent] Use Vector Network Analyzer (Agilent (Agilent) company, trade name E8363C) and split dielectric resonator (Split Post Dielectric Resonator, SPDR) to measure the dielectric constant and the dielectric constant of the resin sheet at 10 GHz Dielectric loss tangent. In addition, the material used in the measurement was left for 24 hours under the conditions of temperature: 24°C to 26°C and humidity 45% to 55% RH.

[Measurement of surface roughness of copper foil] Atomic Force Microscope (AFM) (manufactured by Bruker AXS, trade name: Dimension Icon Scanning Probe Microscope (SPM)), probe (Bruker AXS) AXS) company, trade name: TESPA (NCHV), tip curvature radius 10 nm, spring constant 42 N/m), in tapping mode (tapping mode) to measure the copper foil surface of 80 μm × 80 μm range, And find the ten-point average roughness (Rzjis).

The abbreviations used in the synthesis examples indicate the following compounds. ○BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride ○BPADA: 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride ○PMDA: Pyromellitic dianhydride ○BTDA: 3,3',4,4'-benzophenone tetracarboxylic dianhydride ○m-TB: 2,2'-dimethyl-4,4'-diaminobiphenyl ○TPE-R: 1,3-bis(4-aminophenoxy)benzene ○Dianiline-M: 1,3-bis[2-(4-aminophenyl)-2-propyl]benzene ○BAPP: 2,2-bis[4-(4-aminophenoxy)phenyl]propane ○DDA: aliphatic diamine with 36 carbon atoms (manufactured by CRODA Japan Co., Ltd., trade name: PRIAMINE 1074, amine value: 205 mgKOH/g, cyclic structure and chain The structure of the dimer diamine mixture, the content of the dimer component: 95% by weight or more) ○DMAc: N,N-Dimethylacetamide ○NMP: N-methyl-2-pyrrolidone ○N-12: Dihydrazine dodecanedioic acid ○OP935: Organic aluminum phosphinate (manufactured by Clariant Japan, trade name: Exolit OP935) ○R710: (trade name, manufactured by Printec (stock), bisphenol epoxy resin, epoxy equivalent 170, liquid at room temperature, weight average molecular weight: about 340) ○VG3101L: (trade name, manufactured by Printec (Stock), multifunctional epoxy resin, epoxy equivalent: 210, softening point 39℃～46℃) ○SR35K: (trade name, manufactured by Printec Co., Ltd., epoxy resin, epoxy equivalent: 930～940, softening point: 86℃～98℃) ○YDCN-700-10: (trade name, manufactured by Nippon Steel Chemical & Materials Co., Ltd., cresol novolac epoxy resin, epoxy equivalent 210, softening point 75℃～85℃) ○Milex XLC-LL: (trade name, manufactured by Mitsui Chemicals Co., Ltd., phenol resin, hydroxyl equivalent: 175, softening point: 77°C, water absorption: 1% by mass, heating mass reduction rate: 4 quality%) ○HE200C-10: (trade name, manufactured by AIR WATER (stock), phenol resin, hydroxyl equivalent: 200, softening point: 65℃～76℃, water absorption: 1 mass%, heating mass reduction rate: 4 quality%) ○HE910-10: (trade name, manufactured by AIR WATER (stock), phenol resin, hydroxyl equivalent: 101, softening point: 83°C, water absorption: 1 mass%, heating mass reduction rate: 3 mass%) ○SC1030-HJA: (trade name, manufactured by Admatechs (stock), silica filler dispersion, average particle size: 0.25 μm) ○Aerosil R972: (trade name, manufactured by Aerosil Japan (stock), silicon dioxide, average particle size: 0.016 μm) ○Acrylic gum HTR-860P-30B-CHN: (Sample name, manufactured by Teikoku Chemical Industry Co., Ltd., weight average molecular weight: 230,000, glycidyl functional monomer ratio: 8%, Tg: -7 ℃) ○Acrylic gum HTR-860P-3CSP: (Sample name, manufactured by Teikoku Chemical Industry Co., Ltd., weight average molecular weight: 800,000, glycidyl functional monomer ratio: 3%, Tg: -7°C) ○A-1160: (trade name, manufactured by GE Toshiba Co., Ltd., γ-ureidopropyltriethoxysilane) ○A-189: (trade name, manufactured by GE Toshiba Co., Ltd., γ-mercaptopropyl trimethoxysilane) ○Curezol 2PZ-CN: (trade name, manufactured by Shikoku Chemical Co., Ltd., 1-cyanoethyl-2-phenylimidazole) ○RE-810NM: (trade name, manufactured by Nippon Kayaku Co., Ltd., diallyl bisphenol A diglycidyl ether (property: liquid)) ○phoret SCS: (trade name: manufactured by Soken Chemical Co., Ltd., acrylic polymer containing styrene groups (Tg: 70°C, weight average molecular weight: 15000)) ○BMI-1: (trade name, manufactured by Tokyo Kasei Co., Ltd., 4,4'-bismaleimide diphenylmethane) ○TPPK: (trade name: manufactured by Tokyo Kasei Co., Ltd., tetraphenylphosphonium tetraphenylborate) ○HP-P1: (trade name, manufactured by Mizushima Alloy Iron Co., Ltd., boron nitride filler)

(Synthesis example 1) <Preparation of Resin Solution A for Adhesive Layer> Cyclohexanone was added to a composition containing (a) epoxy resin and phenol resin as thermosetting resin and (c) inorganic filler as the product name and composition ratio (unit: parts by mass) in Table 1, and stirred and mixed . (B) Acrylic rubber as a high molecular weight component shown in Table 1 was added thereto and stirred, and then (e) coupling agent and (d) hardening accelerator shown in Table 1 were added, and stirred until each component became Until it is uniform, resin solution A for the adhesive layer is obtained.

[Table 1] classification name Synthesis example 1 Epoxy resin R710 twenty four VG3101L twenty one SR35K 20 YDCN-700-10 1.4 Phenol resin Milex (milex) XLC-LL 1.2 HE910-10 17 HE200C-10 15 Inorganic filler Aerosil R972 0.82 SC1030-HJA 61 Coupling agent A-189 0.29 A-1160 0.59 Hardening accelerator Curezol 2PZ-CN 0.025 Acrylic rubber HTR-860P-30B-CHN 27 HTR-860P-3CSP 12

(Synthesis example 2) ＜Synthesis of polyimide resin (PI-1) and preparation of resin solution B for adhesive layer＞ Put 1,3-bis(3-aminopropyl)tetramethyldisiloxane (manufactured by Shin-Etsu Chemical Co., Ltd., product) into a 300 mL flask equipped with a thermometer, agitator, cooling tube, and nitrogen inlet tube Name: LP-7100) 15.53 g, polyoxypropylene diamine (manufactured by BASF Co., Ltd., trade name: D400, molecular weight: 450) 28.13 g, and NMP 100.0 g and stirred to prepare a reaction liquid. After the diamine was dissolved, while cooling the flask in an ice bath, 4,4'-oxydiphthalic dianhydride, which was previously purified by recrystallization from anhydrous acetic acid, was added to the reaction liquid in small amounts at a time 32.30 g. After reacting at room temperature (25°C) for 8 hours, 67.0 g of xylene was added, and heating was performed at 180°C while blowing in nitrogen gas, thereby removing xylene and water azeotropically. The reaction liquid was poured into a large amount of water, and the precipitated resin was collected by filtration, and dried to obtain a polyimide resin (PI-1). The molecular weight of the obtained polyimide resin (PI-1) was measured by gel permeation chromatography (GPC). As a result, in terms of polystyrene conversion, the number average molecular weight Mn=22,400, and the weight average molecular weight Mw =70200. Using the obtained polyimide resin (PI-1), the components were blended in the composition ratio (unit: parts by mass) shown in Table 2 to obtain a resin solution B for the adhesive layer.

[Table 2] classification name Synthesis Example 2 Thermoplastic resin PI-1 100 Reactive plasticizer RE-810NM 40 Styryl compounds Phoret SCS 40 Compounds with maleimide groups BMI-1 40 Hardening accelerator TPPK 0.2 Inorganic filler HP-P1 twenty two Solvent NMP 270

(Synthesis example 3) <Preparation of Resin Solution C for Adhesive Layer> Put 44.92 g of BTDA (0.139 mol) into a 500 mL four-necked flask with a nitrogen inlet tube, agitator, thermocouple, Dean-Stark trap, and cooling tube. 75.08 g of DDA (0.141 mol), 168 g of NMP, and 112 g of xylene were mixed at 40° C. for 30 minutes to prepare a polyamide acid solution. The polyamide acid solution was heated to 190°C, heated and stirred for 4 hours, and the distilled water and xylene were removed to the outside of the system. Thereafter, it was cooled to 100°C, 112 g of xylene was added and stirred, and then cooled to 30°C to complete the imidization, and a resin solution C (solid content: 29.5% by weight, weight average molecular weight) for the adhesive layer was obtained. : 75,700).

(Synthesis example 4) <Preparation of Resin Solution D for Adhesive Layer> 42.51 g of BPADA (0.082 mol), 34.30 g of DDA (0.066 mol), 6.56 g of BAPP (0.016 mol), 208 g of NMP, and 112 g of xylene were used as the raw material composition. In the same manner as in Synthesis Example 3, a polyamic acid solution was prepared. The polyamide acid solution was processed in the same manner as in Synthesis Example 3 to obtain a resin solution D for an adhesive layer (solid content: 30.0% by weight, weight average molecular weight: 65,000).

(Synthesis example 5) ＜Preparation of polyamide acid solution 1 for insulating resin layer＞ Under nitrogen flow, 64.20 g of m-TB (0.302 mol) and 5.48 g of bisaniline-M (0.016 mol) and DMAc with a solid content concentration of 15% by weight after polymerization were put into the reaction tank. Stir and dissolve at room temperature. Next, 34.20 g of PMDA (0.157 mol) and 46.13 g of BPDA (0.157 mol) were added. After that, stirring was continued for 3 hours at room temperature to carry out the polymerization reaction to prepare polyamide acid solution 1 (viscosity: 26,500 cps) ).

(Synthesis example 6) <Preparation of polyamide acid solution 2 for insulating resin layer> 69.56 g of m-TB (0.328 mol), 542.75 g of TPE-R (1.857 mol), DMAc with a solid content concentration of 12% by weight after polymerization, 194.39 g of PMDA (0.891 mol), and Except having 393.31 g of BPDA (1.337 mol) as a raw material composition, it carried out similarly to the synthesis example 3, and prepared the polyamide acid solution 2 (viscosity: 2,650 cps).

(Production example 1) <Preparation of Resin Sheet A for Adhesive Layer> Apply the resin solution A for the adhesive layer to the silicone-treated surface of the release substrate (length×width×thickness=320 mm×240 mm×25 μm) so that the thickness after drying is 50 μm, and then , Heating and drying at 80° C. for 15 minutes, and further drying at 120° C. for 15 minutes, and then peeling from the release substrate, thereby preparing a resin sheet A. In addition, regarding the resin sheet A, in order to evaluate the physical properties after curing, it was heated in an oven at 120°C for 2 hours, and heated at 170°C for 3 hours. At this time, regarding the cured resin sheet A, the Tg was 95°C, the storage elastic modulus at 50°C was 960 MPa, and the maximum storage elastic modulus in the range of 180°C to 260°C was 7 MPa.

(Production example 2) <Preparation of resin sheet B for adhesive layer> Apply the resin solution B for the adhesive layer to the silicone-treated surface of the release substrate (length×width×thickness=320 mm×240 mm×25 μm) so that the thickness after drying is 50 μm, and then , Heating and drying at 80° C. for 15 minutes, and further drying at 120° C. for 15 minutes, and then peeling from the release substrate, thereby preparing a resin sheet B. In addition, regarding the resin sheet B, in order to evaluate the physical properties after curing, it was heated in an oven at 120°C for 2 hours, and heated at 170°C for 3 hours. At this time, regarding the cured resin sheet B, the Tg is 100°C or less, the storage elastic modulus at 50°C is 1800 MPa or less, and the maximum storage elastic modulus in the range of 180°C to 260°C is 70 MPa.

(Production example 3) <Preparation of resin sheet C for adhesive layer> Mix 1.8 g of N-12 (0.0036 mol) and 12.5 g of OP935 in 169.49 g of resin solution C for the adhesive layer (50 g in terms of solid content), and add 6.485 g of NMP and 19.345 g of OP935 Xylene was diluted to prepare polyimide varnish 1.

The polyimide varnish 1 was applied to the silicone-treated surface of the release substrate (length×width×thickness=320 mm×240 mm×25 μm) so that the thickness after drying was 50 μm. It was heated and dried at 80°C for 15 minutes, and peeled off from the release substrate, thereby preparing a resin sheet C. The Tg of the resin sheet C is 78°C, the storage elastic modulus at 50°C is 800 MPa, and the maximum storage elastic modulus in the range of 180°C to 260°C is 10 MPa. In addition, the dielectric constant (Dk) and the dielectric loss tangent (Df) are 2.68 and 0.0028, respectively.

(Production example 4) <Preparation of Resin Sheet D for Adhesive Layer> Apply the resin solution D for the adhesive layer to the silicone-treated surface of the release base material (length×width×thickness=320 mm×240 mm×25 μm) so that the thickness after drying is 50 μm, and then , Heating and drying at 80° C. for 15 minutes, and peeling from the release substrate, thereby preparing a resin sheet D. The Tg of the resin sheet D is 82°C, the storage elastic modulus at 50°C is 1800 MPa or less, and the maximum storage elastic modulus in the range of 180°C to 260°C is 2 MPa or less. In addition, the dielectric constant (Dk) and the dielectric loss tangent (Df) are 2.80 and 0.0026, respectively.

(Production example 5) ＜Preparation of single-sided metal-clad laminates＞ On copper foil 1 (electrolytic copper foil, thickness: 12 μm, surface roughness Rz on the resin layer side: 0.6 μm), the polyamide acid solution is uniformly coated so that the cured thickness is about 2 μm to 3 μm 2. After that, heat and dry at 120°C to remove the solvent. Next, the polyamide acid solution 1 was uniformly applied thereon so that the thickness after curing was about 21 μm, and it was heated and dried at 120°C to remove the solvent. Furthermore, the polyamide acid solution 2 was uniformly coated thereon so that the thickness after curing was about 2 μm to 3 μm, and then heated and dried at 120° C. to remove the solvent. Furthermore, stepwise heat treatment was performed from 120°C to 360°C to complete the imidization, and a single-sided metal-clad laminate 1 was prepared. The dimensional change rate of the single-sided metal-clad laminate 1 is as follows. Dimensional change rate after etching in MD direction (long side direction): 0.01% Dimensional change rate after etching in the TD direction (width direction): -0.04% Dimensional change rate in MD direction (long side direction) after heating: -0.03% Dimensional change rate in the TD direction (width direction) after heating: -0.01% In addition, the polyimide film 1 (thickness: 25 μm) prepared by etching and removing the copper foil 1 of the single-sided metal-clad laminate 1 using ferric chloride aqueous solution has a CTE of 20.0 ppm/K and a dielectric constant (Dk) And the dielectric loss tangent (Df) are 3.40 and 0.0029 respectively.

[Example 1] The resin solution A for the adhesive layer was applied to the resin surface of the single-sided metal-clad laminate 1 so that the thickness after drying was 50 μm, and then heated and dried at 80°C for 15 minutes, and then at 120°C Drying was performed for 15 minutes, thereby preparing a single-sided metal-clad laminated board 1 with an adhesive layer. In addition, regarding the single-sided metal-clad laminate 1 with an adhesive layer, in order to evaluate the physical properties of the adhesive layer after hardening, it was heated in an oven at 120°C for 2 hours and at 170°C for 3 hours. The evaluation results of the heated single-sided metal-clad laminated sheet 1 with an adhesive layer are as follows. Dimensional change rate after etching in MD direction: -0.05% Dimensional change rate after etching in TD direction: -0.02% Dimensional change rate in MD direction after heating: -0.01% Dimensional change rate after heating in TD direction: -0.03% There is no problem in the dimensional change of the single-sided metal-clad laminate 1 with an adhesive layer after heating. In addition, the CTE of the resin laminate 1 (thickness: 75 μm) prepared by etching away the copper foil 1 of the single-sided metal-clad laminate 1 with an adhesive layer after heating was 26.2 ppm/K.

[Example 2] The resin solution B for the adhesive layer was applied to the resin surface of the single-sided metal-clad laminate 1 so that the thickness after drying was 50 μm, and then heated and dried at 80°C for 15 minutes, and then at 120°C Drying was performed for 15 minutes, thereby preparing a single-sided metal-clad laminated board 2 with an adhesive layer. In addition, regarding the single-sided metal-clad laminate 2 with an adhesive layer, in order to evaluate the physical properties of the adhesive layer after hardening, it was heated in an oven at 120°C for 2 hours and at 170°C for 3 hours. The evaluation results of the heated single-sided metal-clad laminate 2 with an adhesive layer are as follows. Dimensional change rate after etching in MD direction: -0.08% Dimensional change rate after etching in TD direction: -0.06% Dimensional change rate in MD direction after heating: -0.03% Dimensional change rate in the TD direction after heating: -0.06% There is no problem in the dimensional change of the single-sided metal-clad laminate 2 with an adhesive layer after heating. In addition, the CTE of the resin laminate 2 (thickness: 75 μm) prepared by etching away the copper foil 1 of the single-sided metal-clad laminate 2 with an adhesive layer after heating was 25.0 ppm/K.

[Example 3] The polyimide varnish 1 was applied to the resin surface of the single-sided metal-clad laminate 1 so that the thickness after drying was 50 μm, and then heated and dried at 80°C for 15 minutes to prepare an adhesive layer The single-sided metal-clad laminate 3. In addition, the single-sided metal-clad laminate 3 with an adhesive layer was evaluated after heating in an oven at 180°C for 1 minute and at 150°C for 30 minutes. The results are as follows. Dimensional change rate after etching in MD direction: -0.05% Dimensional change rate after etching in TD direction: -0.04% Dimensional change rate in MD direction after heating: 0.05% Dimensional change rate after heating in TD direction: 0.01% There is no problem with the dimensional change of the single-sided metal-clad laminate 3 with an adhesive layer after heating. In addition, the resin laminate 3 (thickness: 75 μm) prepared by etching and removing the copper foil 1 of the heated single-sided metal-clad laminate 3 with an adhesive layer had a CTE of 25.6 ppm/K and a dielectric constant (Dk ) And the dielectric loss tangent (Df) are 2.92 and 0.0028 respectively.

[Example 4] The resin solution D for the adhesive layer was applied to the resin surface of the single-sided metal-clad laminate 1 so that the thickness after drying was 50 μm, and then heated and dried at 80°C for 15 minutes, thereby preparing a tape adhesive Layered single-sided metal-clad laminated board 4. In addition, the single-sided metal-clad laminate 4 with an adhesive layer was evaluated after heating in an oven at 180°C for 1 minute and at 150°C for 30 minutes. As a result, there was no problem with the dimensional change, and the dielectric constant ( Dk) and dielectric loss tangent (Df) are 3.00 and 0.0027 respectively.

[Example 5] A liquid crystal polymer film (manufactured by Kuraray, trade name: CT-Z, thickness: 25 μm, CTE: 18 ppm/K, heat distortion temperature: 300°C, Dk: 3.40, Df: 0.0022) was set as As the insulating base material, a double-sided metal-clad laminate 1 having copper foils 1 provided on both surfaces of the insulating base material is prepared. The copper foil 1 on one side of the double-sided metal-clad laminated board 1 is etched away to prepare a single-sided metal-clad laminated board 2.

The polyimide varnish 1 was applied to the resin surface of the single-sided metal-clad laminate 2 so that the thickness after drying was 50 μm, and then heated and dried at 80°C for 15 minutes, thereby preparing an adhesive layer The single-sided metal-clad laminate5. In addition, the single-sided metal-clad laminate 5 with an adhesive layer was evaluated after being heated in an oven at 180°C for 1 minute and at 150°C for 30 minutes. As a result, there was no problem with the dimensional change, and the dielectric constant ( Dk) and dielectric loss tangent (Df) are 2.92 and 0.0026 respectively.

[Example 6] The resin solution D for the adhesive layer was applied to the resin surface of the single-sided metal-clad laminate 2 so that the thickness after drying was 50 μm, and then heated and dried at 80°C for 15 minutes, thereby preparing a tape adhesive Layered single-sided metal-clad laminated board 6. In addition, the single-sided metal-clad laminate 6 with an adhesive layer was evaluated after heating in an oven at 180°C for 1 minute and at 150°C for 30 minutes. As a result, there was no problem with dimensional changes, and the dielectric constant ( Dk) and dielectric loss tangent (Df) are 3.00 and 0.0025 respectively.

[Example 7] The copper foil 1 of the single-sided metal-clad laminate 1 is subjected to circuit processing by a subtractive method to prepare a single-sided wiring board 1 on which a conductor circuit layer is formed. The two copper foils 1 of the single-sided metal-clad laminate 3 with adhesive layers are subjected to circuit processing by the subtractive method to prepare two single-sided wiring boards 1 with adhesive layers on which conductor circuit layers are formed.

The conductive circuit layer of the single-sided wiring board 1 and the adhesive layer of a single-sided wiring board 1 with an adhesive layer, the conductive circuit layer of a single-sided wiring board 1 with an adhesive layer and the other with an adhesive layer After the adhesive layers of the single-sided wiring board 1 were overlapped so as to face each other, they were subjected to thermocompression bonding under the conditions of 160° C. and 4 MPa for 60 minutes, thereby preparing the multilayer circuit board 1. In the crimping surface of the multilayer circuit board 1, the adhesive is sufficiently filled into the conductive circuit layer, and there is no disturbance of the conductive circuit caused by the thermal compression bonding step.

[Example 8] Prepare two single-sided wiring substrates 1 with adhesive layers, and place the adhesive layer of one single-sided wiring substrate 1 with adhesive layer and the adhesive layer of the other single-sided wiring substrate 1 with adhesive layer facing each other After superposing the method, the thermocompression bonding was performed at 160° C. and 4 MPa for 60 minutes, thereby preparing a double-sided circuit board 1. In the crimping surface of the double-sided circuit board 1, the adhesive layers are sufficiently bonded to each other, and there is no disturbance of the conductor circuit caused by the thermal compression bonding step.

[Example 9] The two copper foils 1 of the single-sided metal-clad laminates 4 with adhesive layers are subjected to circuit processing by the subtractive method to prepare two single-sided wiring boards 2 with adhesive layers on which conductor circuit layers are formed.

The conductor circuit layer of a single-sided wiring board 1 and an adhesive layer of a single-sided wiring board 2 with an adhesive layer, a conductive circuit layer of a single-sided wiring board 2 with an adhesive layer and another adhesive layer After the adhesive layers of the single-sided wiring board 2 were overlapped so as to face each other, they were subjected to thermocompression bonding under the conditions of 160° C. and 4 MPa for 60 minutes, thereby preparing the multilayer circuit board 2. In the crimping surface of the multilayer circuit board 2, the adhesive is sufficiently filled into the conductor circuit layer, and there is no disturbance of the conductor circuit caused by the thermal compression step.

[Example 10] Prepare two single-sided wiring substrates 2 with adhesive layers, and place the adhesive layer of one single-sided wiring substrate 2 with adhesive layer and the adhesive layer of the other single-sided wiring substrate 2 with adhesive layer facing each other After superposing the method, the thermocompression bonding is performed at 160° C. and 4 MPa for 60 minutes, thereby preparing a double-sided circuit board 2. In the crimping surfaces of the double-sided circuit board 2, the adhesive layers are sufficiently bonded to each other, and there is no disturbance of the conductor circuit caused by the thermal compression bonding step.

[Example 11] The copper foil 1 of the single-sided metal-clad laminate 2 is subjected to circuit processing by the subtractive method to prepare a single-sided wiring board 2 on which a conductor circuit layer is formed. The two copper foils 1 of the single-sided metal-clad laminate 5 with adhesive layers are subjected to circuit processing by the subtractive method to prepare two single-sided wiring substrates 3 with adhesive layers on which conductor circuit layers are formed.

The conductive circuit layer of the single-sided wiring board 2 and the adhesive layer of a single-sided wiring board 3 with an adhesive layer, the conductive circuit layer of a single-sided wiring board 3 with an adhesive layer and the other with an adhesive layer After the adhesive layers of the single-sided wiring board 3 were overlapped so as to face each other, they were subjected to thermocompression bonding at 160° C. and 4 MPa for 60 minutes, thereby preparing a multilayer circuit board 3. In the crimping surface of the multilayer circuit board 3, the adhesive is sufficiently filled into the conductor circuit layer, and there is no disturbance of the conductor circuit caused by the thermal compression bonding step.

[Example 12] Prepare two single-sided wiring boards 3 with adhesive layers, and place the adhesive layer of one single-sided wiring board 3 with adhesive layer and the adhesive layer of the other single-sided wiring board 3 with adhesive layer facing each other After the methods were superimposed, thermocompression bonding was performed at 160° C. and 4 MPa for 60 minutes, thereby preparing a double-sided circuit board 3. In the crimping surfaces of the double-sided circuit board 3, the adhesive layers are sufficiently bonded to each other, and there is no disturbance of the conductor circuit caused by the thermal compression step.

[Example 13] The two copper foils 1 of the single-sided metal-clad laminate 6 with adhesive layers are subjected to circuit processing by the subtractive method to prepare two single-sided wiring boards 4 with adhesive layers on which conductor circuit layers are formed.

The conductive circuit layer of the single-sided wiring board 2 and the adhesive layer of a single-sided wiring board 4 with an adhesive layer, the conductive circuit layer of a single-sided wiring board 4 with an adhesive layer and the other with an adhesive layer After the adhesive layers of the single-sided wiring board 4 were overlapped so as to face each other, they were subjected to thermocompression bonding under the conditions of 160° C. and 4 MPa for 60 minutes, thereby preparing the multilayer circuit board 4. In the crimping surface of the multilayer circuit board 4, the adhesive is sufficiently filled into the conductor circuit layer, and there is no disturbance of the conductor circuit caused by the thermal compression step.

[Example 14] Prepare two single-sided wiring boards 4 with adhesive layers, and place the adhesive layer of one single-sided wiring board 4 with adhesive layer and the adhesive layer of the other single-sided wiring board 4 with adhesive layer facing each other After superposing the method, the thermocompression bonding was performed at 160° C. and 4 MPa for 60 minutes, thereby preparing a double-sided circuit board 4. In the crimping surface of the double-sided circuit board 4, the adhesive layers are sufficiently bonded to each other, and there is no disturbance of the conductor circuit caused by the thermal compression bonding step.

As mentioned above, the embodiment of the present invention has been described in detail for the purpose of illustration, but the present invention is not restricted by the foregoing embodiment and can be variously modified.

10: Insulating resin layer 20: Metal layer 30: Adhesive layer 40: Single-sided metal-clad laminate 50: Conductor circuit layer 100: metal clad laminate 101: Circuit board 102: Circuit board unit 110: Arbitrary circuit board 200, 201: Multilayer circuit board T1: Total thickness T2, T3: thickness

Fig. 1 is a cross-sectional view showing the structure of a metal-clad laminate according to an embodiment of the present invention. Fig. 2 is a cross-sectional view showing the structure of a circuit board according to an embodiment of the present invention. Fig. 3 is a cross-sectional view showing the structure of the multilayer circuit board according to the first embodiment of the present invention. Fig. 4 is an explanatory diagram showing a manufacturing process of the multilayer circuit board according to the first embodiment of the present invention. Fig. 5 is a cross-sectional view showing the structure of a multilayer circuit board according to a second embodiment of the present invention. Fig. 6 is an explanatory diagram showing a manufacturing process of a multilayer circuit board according to a second embodiment of the present invention.

10: Insulating resin layer

30: Adhesive layer

50: Conductor circuit layer

101: Circuit board

110: Arbitrary circuit board

200: Multilayer circuit board

Claims (12)

A metal-clad laminated board includes: Insulating resin layer; A metal layer, laminated on one side of the insulating resin layer; and Adhesive layer, laminated on the other side of the insulating resin layer, and The resin constituting the adhesive layer is a thermoplastic resin or a thermosetting resin, and satisfies the following conditions (i) to (iii): (I) The storage elastic modulus at 50°C is below 1800 MPa; (Ii) The maximum storage elastic modulus in the temperature range from 180°C to 260°C is 800 MPa or less; (Iii) The glass transition temperature (Tg) is 180°C or less. The metal-clad laminate as described in item 1 of the patent application, wherein the thermoplastic resin is an adhesive polyimide containing tetracarboxylic acid residues and diamine residues, and The adhesive polyimide contains more than 50 mol parts of diamine residues derived from dimer acid-type diamines relative to 100 mol parts of the total amount of the diamine residues, and the dimerization The acid-type diamine is formed by substituting the two terminal carboxylic acid groups of the dimer acid with a primary aminomethyl or amino group. The metal-clad laminate according to the first item of the patent application, wherein the metal-clad laminate is a material of a circuit board formed by processing the metal layer into wiring. The metal-clad laminate according to item 2 of the scope of patent application, wherein the adhesive polyimide is contained in a total of 90 mol parts or more with respect to 100 mol parts of the total amount of the tetracarboxylic acid residues The tetracarboxylic acid residue derived from the tetracarboxylic anhydride represented by the following general formula (1) and/or general formula (2):

In the general formula (1), X represents a single bond or a divalent group selected from the following formulae. In the general formula (2), the cyclic moiety represented by Y represents the formation of a 4-membered ring, a 5-membered ring, and 6 Cyclic saturated hydrocarbon group in a ring, a 7-membered ring or an 8-membered ring,

In the formula, Z represents -C ₆ H ₄ -, -(CH ₂ )n- or -CH ₂ -CH(-OC(=O)-CH ₃ )-CH ₂ -, and n represents an integer of 1-20 . The metal-clad laminate as described in item 2 of the scope of the patent application, wherein the adhesive polyimide is 100 mole parts and more than 50 mole parts and 99 mole parts relative to the total amount of the diamine residues. The diamine residue derived from the dimer acid-type diamine is contained in the range of ear parts or less, and the diamine residue derived from the dimer acid-type diamine is contained in the range of 1 mol part or more and 50 mol part or less selected from the following general formula (B1) ~Diamine residue derived from at least one diamine compound in the diamine compound represented by the general formula (B7):

In formulas (B1) to (B7), R ₁ independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, and the linking group A independently represents a group selected from -O-, -S-, -CO-, The divalent group in -SO-, -SO ₂ -, -COO-, -CH ₂ -, -C(CH ₃ ) ₂ -, -NH- or -CONH-, n ₁ independently represents an integer from 0 to 4 ; Among them, from the formula (B3) remove the part that overlaps with the formula (B2), from the formula (B5) remove the part that overlaps with the formula (B4). A circuit substrate, including: Insulating resin layer; A conductive circuit layer formed on one side of the insulating resin layer; and The adhesive layer is laminated on the other side of the insulating resin layer, and in the circuit substrate, The resin constituting the adhesive layer is a thermoplastic resin or a thermosetting resin, and satisfies the following conditions (i) to (iii): (I) The storage elastic modulus at 50°C is below 1800 MPa; (Ii) The maximum storage elastic modulus in the temperature range from 180°C to 260°C is 800 MPa or less; (Iii) The glass transition temperature (Tg) is 180°C or less. The circuit board as described in item 6 of the scope of patent application, wherein the thermoplastic resin is an adhesive polyimide containing a tetracarboxylic acid residue and a diamine residue, and The adhesive polyimide contains more than 50 mol parts of diamine residues derived from dimer acid-type diamines relative to 100 mol parts of the total amount of the diamine residues, and the dimerization The acid-type diamine is formed by substituting the two terminal carboxylic acid groups of the dimer acid with a primary aminomethyl or amino group. The circuit board according to item 7 of the scope of patent application, characterized in that the adhesive polyimide is contained in a total of 90 mol parts with respect to 100 mol parts of the total amount of the tetracarboxylic acid residues The above tetracarboxylic acid residue derived from the tetracarboxylic anhydride represented by the following general formula (1) and/or general formula (2):

In the general formula (1), X represents a single bond or a divalent group selected from the following formulae. In the general formula (2), the cyclic moiety represented by Y represents the formation of a 4-membered ring, a 5-membered ring, and 6 A cyclic saturated hydrocarbon group in a ring, a 7-membered ring or an 8-membered ring;

In the formula, Z represents -C ₆ H ₄ -, -(CH ₂ )n- or -CH ₂ -CH(-OC(=O)-CH ₃ )-CH ₂ -, and n represents an integer of 1-20 . The circuit substrate according to item 7 of the scope of the patent application, wherein the adhesive polyimide is 100 mol parts and more than 50 mol parts and 99 mol parts relative to the total amount of the diamine residues The diamine residue derived from the dimer acid type diamine is contained in the following range, and the diamine residue is contained in the range of 1 mol part or more and 50 mol part or less selected from the following general formula (B1) to general Diamine residue derived from at least one diamine compound in the diamine compound represented by formula (B7):

In formulas (B1) to (B7), R ₁ independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, and the linking group A independently represents a group selected from -O-, -S-, -CO-, The divalent group in -SO-, -SO ₂ -, -COO-, -CH ₂ -, -C(CH ₃ ) ₂ -, -NH- or -CONH-, n ₁ independently represents an integer from 0 to 4 ; Among them, from the formula (B3) remove the part that overlaps with the formula (B2), from the formula (B5) remove the part that overlaps with the formula (B4). A multilayer circuit substrate, which is a multilayer circuit substrate in which a plurality of circuit substrates are laminated, and is characterized in that: At least one circuit board as described in any one of items 6 to 9 of the scope of patent application is included as the circuit board. A manufacturing method of a multilayer circuit substrate includes: A step of preparing a plurality of circuit substrates, the circuit substrate including an insulating resin layer, a conductive circuit layer formed on one side of the insulating resin layer, and an adhesive layer laminated on the other side of the insulating resin layer; and The step of overlapping and crimping the conductive circuit layer of one circuit substrate and the adhesive layer of the other circuit substrate in an opposing manner. A manufacturing method of a multilayer circuit substrate includes: A step of preparing a plurality of circuit substrates, the circuit substrate including an insulating resin layer, a conductive circuit layer formed on one side of the insulating resin layer, and an adhesive layer laminated on the other side of the insulating resin layer; and The step of overlapping and crimping the adhesive layer of one circuit substrate and the adhesive layer of the other circuit substrate in an opposing manner.

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