JP2001015877A - Metal base printed wiring board, metal base multilayered printed wiring board and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal base multilayered printed wiring board by using a solder heat resistant thermoplastic insulating layer that can be thermally bonded to a conductor foil and a metal base at a relatively low temperature, and yet can surely accomplish integral bonding. SOLUTION: This metal base multilayered printed wiring board is formed by preparing a thermally bondable film 10 for interlayer connection of a layered electrical circuit by opening holes 8 that penetrate both faces of a filmy insulator 7 and filling these holes with a conductive paste 9, and forming a filmy wiring board 6 by thermally bonding a conductor foil and providing printed circuits 11 on both faces of the film 10, then thermally bonding the filmy wiring board 6 on one or both faces of a metal board 4 via an insulating layer 5. In the multilayered printed wiring board, the heat quantity of crystal fusion ΔHm and the heat quantity of crystallization ΔHc that is generated by crystallization during temperature rise, of a thermoplastic resin composition constituting the insulating layer 5 and the thermally bonded filmy wiring board, having characteristics that satisfy a relation given by the expression (ΔHm-ΔHc)/ΔHm}<=0.5 is thermally bonded so as to satisfy a relation (ΔHm-ΔHc)/ΔHm}>=0.7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a metal-based printed wiring board, a metal-based multilayer printed wiring board, and a method for manufacturing the same.

[0002]

2. Description of the Related Art As a metal-based printed wiring board, a conductor foil is laminated on one or both sides of a metal base (base material or core) such as aluminum, iron, copper, zinc, etc. via an insulating layer and bonded and integrated to form a conductor. It is known that a printed circuit is formed by etching a foil.

[0003] A metal-based printed wiring board is excellent in heat resistance, flame retardancy, shielding effect, mechanical strength, and the like due to the characteristics of the metal base, and has a characteristic that heat dissipation is particularly good. That is, since the metal of the base has a high thermal conductivity, the metal base printed wiring board has good heat dispersion due to conduction, suppresses a local rise in the substrate temperature, and has a high heat dissipation effect.

As a material for forming an insulating layer of a metal-based printed wiring board, an epoxy resin containing a filler having good heat dissipation properties such as alumina is generally used.

[0005] However, there are problems in workability such as a problem of storage stability of the semi-cured epoxy prepreg before pressing and a long time of about 2 hours for pressing.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problem and to use a thermoplastic insulating layer having solder heat resistance at a relatively low temperature with respect to a conductive foil and a metal base. An object of the present invention is to provide a metal-based printed wiring board or a metal-based multilayer printed wiring board that can be heat-fused in a short time and that is securely bonded and integrated.

Another object of the invention according to the manufacturing method of the present invention is to surely heat-bond a conductive foil and a metal base with a thermoplastic insulating layer in a simple process to efficiently produce a metal-based multilayer printed wiring board. Is to manufacture.

[0008]

In the invention relating to the metal-based printed wiring board of the present application, in order to solve the above-mentioned problems, one or both sides of the metal plate are interposed via an insulating layer made of a thermoplastic resin composition. In a metal-based printed wiring board in which a conductive foil is heat-sealed and a printed circuit is formed with the conductive foil, the insulating layer is made of 65 to 35% by weight of a polyarylketone resin having a crystal melting peak temperature of 260 ° C. or higher, and amorphous. And a glass transition temperature of 150 to 230 ° C. measured when the temperature of the thermoplastic resin composition is increased by differential scanning calorimetry. The relationship between the heat of crystal melting .DELTA.Hm and the heat of crystallization .DELTA.Hc generated by crystallization during temperature increase satisfying the relationship represented by the following formula (A) is represented by the following formula (B). It was a metal base printed circuit board, characterized in that is obtained by heat-sealing so as to satisfy the relationship.

Formula (A): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 Formula (B): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 The conductive foil has a roughened surface. Preferably, a conductive foil is used, and as the metal plate, a metal plate having a roughened surface is preferably used.

In the invention according to the metal-based multilayer printed wiring board of the present application, in order to solve the above-mentioned problems, a double-sided through-hole is formed in a film-like insulator made of a thermoplastic resin composition, and the inside of the through-hole is formed. A heat-fusible film for interlayer connection of a laminated electric circuit is provided by filling a conductive paste into the film, and a conductive foil is heat-fused on both sides of the heat-sealing film for interlayer connection and a circuit is formed to form a film-like wiring board. A metal-based multilayer printed wiring board in which a film-shaped wiring board is heat-sealed on one or both sides of a metal plate via an insulating layer made of the thermoplastic resin composition, wherein the heat-sealed insulating layer and heat The thermoplastic resin composition constituting the fused film-shaped wiring board has a crystal melting peak temperature of 2
65-35% by weight of polyarylketone resin at 60 ° C or higher
And 35 to 65% by weight of an amorphous polyetherimide resin, and the thermoplastic resin composition has a glass transition temperature of 150 to 50 when measured by differential scanning calorimetry.
At 230 ° C., a material having a characteristic in which the relationship between the heat of crystal melting ΔHm and the heat of crystallization ΔHc generated by crystallization during temperature increase satisfies the relationship represented by the following formula (A) is heated to obtain the following formula (B)
A metal-based printed wiring board characterized by being heat-sealed so as to satisfy the relationship shown in (1).

Formula (A): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 Formula (B): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 The conductive foil has a roughened surface. Preferably, a conductive foil is used, and as the metal plate, a metal plate having a roughened surface is preferably used.

A metal-based printed wiring board or a metal-based multilayer printed wiring board according to the present invention having the above-described structure has an insulating layer containing a predetermined amount of a crystalline polyarylketone resin and an amorphous polyetherimide resin. Having.

The insulating layer has a glass transition temperature of 150 to 23.
A material having a temperature of 0 ° C. and having a relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during temperature increase satisfying the relationship represented by the above formula (A) is heated under predetermined conditions. After the fusion, the relationship represented by the formula (B) is satisfied. Since the crystallinity of the polyarylketone resin is appropriately advanced by heating at the time of thermal fusion, 26
The insulating layer surely has solder heat resistance to withstand 0 ° C., and has excellent mechanical strength and electrical insulation.

The insulating layer has a high adhesive strength to the conductor foil, and an electric circuit formed by etching the conductor foil is firmly adhered to the insulating layer and hardly peels off. Usually, a conductor foil having a roughened surface or a metal plate having a roughened surface is employed, or a roughened conductor foil and a metal plate are used to increase the adhesive strength.

Further, since the film-like insulator and the conductor foil are bonded by heat without interposing an adhesive such as epoxy resin between the layers, the heat resistance of the metal-based printed wiring board or the metal-based multilayer printed wiring board can be improved. Various properties such as chemical resistance and electrical properties are not governed by the properties of the adhesive, and the excellent properties of the insulating layer are fully utilized.

The heat-fusible film for interlayer connection of the laminated electric circuit is formed of the insulating thermoplastic resin composition, and the opening of the double-sided through-hole is formed by the conductive paste in the double-sided through-hole. It serves as an electrical contact and conducts in a layer thickness direction at a key point of an electric circuit formed on one or both sides of the film.

In the invention according to the method for manufacturing a metal-based multilayer printed wiring board of the present invention, 65-35% by weight of a polyarylketone resin having a crystal melting peak temperature of 260 ° C. or more is used to solve the above-mentioned problems. 35 to 65% by weight of a polyetherimide resin, and has a glass transition temperature of 150 to 2 when measured by differential scanning calorimetry.
Forming a film-like insulator made of a thermoplastic resin composition in which the relationship between the heat of crystal fusion ΔHm at 30 ° C. and the heat of crystallization ΔHc generated by crystallization during temperature increase satisfies the relationship represented by the following formula (I): Then, a double-sided through-hole is formed in the film-shaped insulator and a conductive paste is filled in the through-hole to form a heat-fusible film for interlayer connection of a laminated electric circuit,
After laminating a conductor foil on both sides of the heat-fusible film for interlayer connection and heat-sealing the thermoplastic resin composition so as to satisfy the relationship represented by the following formula (II), a circuit is formed on the conductor foil. Formed and provided a film-like wiring board, the film-like wiring board is overlapped on one or both sides of a metal plate via the film-like insulator, the thermoplastic resin composition constituting each layer is shown in the following (III) Thus, a method of manufacturing a metal-based multilayer printed wiring board, which is performed by heat-sealing so as to satisfy the relationship described above, was adopted.

Formula (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35 Formula (II): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 Formula (III): [(ΔHm−ΔHc) /ΔHm]≧0.7 In the method for producing a multilayer printed wiring board, when the conductor foil is laminated on both sides of the heat-fusible film for interlayer connection and heat-sealed, the heat-sealing of the thermoplastic resin composition is performed. Heat of crystal melting ΔHm and heat of crystallization ΔH generated by crystallization during heating
Thermal fusion is performed so that the relationship with c satisfies the relationship represented by the above formula (II).

Then, a film-like insulator is laminated on one or both sides of the metal plate, and a film-like wiring board formed with a conductive foil on both sides of the above-mentioned heat-fusible film for interlayer connection is laminated thereon. The thermoplastic resin composition having the relationship represented by the formula (II) is thermally fused so as to satisfy the relationship represented by the formula (III).

In this way, the thermoplastic resin composition after the heat fusion becomes an insulating layer having a solder heat resistance of 260 ° C., in which the crystallinity of the polyarylketone resin proceeds appropriately, and The bonding strength with the conductor foil also increases.

When performing heat fusion by heating and pressurizing, the elastic modulus of the thermoplastic resin is reduced in the temperature range where the thermoplastic resin adheres to the conductive foil, and a thermoplastic resin having a low viscosity suitable for a fine wiring pitch is ensured. It is possible to manufacture a good metal-based multilayer printed wiring board that is filled and has extremely high embedding of the inner layer circuit, that is, extremely high insulation reliability.

Since the film-like insulator and the conductive foil are bonded by heat without interposing an adhesive such as an epoxy resin between the layers, various properties such as heat resistance, chemical resistance, and electric properties are not bonded. The excellent properties of the insulating layer are fully utilized without being influenced by the properties of the agent. Also, since there is no step of applying and drying an adhesive or other liquid laminated material during the manufacturing process, a method of manufacturing a multilayer printed wiring board with high manufacturing efficiency can be achieved.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a metal-based printed wiring board, a metal-based multilayer printed wiring board and a method for manufacturing the same according to the present invention will be described below with reference to the accompanying drawings.

The first embodiment shown in FIG. 1 relates to a metal-based printed wiring board, and has a crystal melting peak temperature of 260 ° C. on one surface of a metal plate 1 such as an aluminum plate whose surface is roughened.
Surface roughening of a roughened copper foil or the like via an insulating layer 2 made of a thermoplastic resin composition containing 65 to 35% by weight of the above polyaryl ketone resin and 35 to 65% by weight of an amorphous polyetherimide resin. A metal-based printed wiring board in which a printed circuit 3 is formed by a subtractive method by heat-sealing a conductive
The heat-fused insulating layer 2 that has the glass transition temperature measured by differential scanning calorimetry has a glass transition temperature of 15
0-230 ° C., the relationship between the heat of crystal melting ΔHm and the heat of crystallization ΔHc generated by crystallization during heating is expressed by the following formula (A).
Heat the material that satisfies the relationship shown by the following formula
It was thermally fused to satisfy the relationship shown in (B).

Formula (A): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 Formula (B): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 As shown by a chain line in FIG. The printed wiring board is formed of a thermoplastic resin composition on both sides of the metal plate 1 having a thickness of, for example, about 1.0 to 1.6 mm.
A metal-based printed wiring board having a two-layer (both sides) structure in which a conductive foil is heat-sealed through an insulating layer 2 having a thickness of μm and a printed circuit 3 is formed with the conductive foil.

The second embodiment shown by the solid line in FIG.
An insulating layer 5 made of a thermoplastic resin composition on one surface of a metal plate 4
This is a metal-based multilayer printed wiring board in which a film-shaped wiring board 6 is heat-sealed through the substrate.

As shown in FIGS. 2 (a) and 2 (b), the heat-fusible film 10 for interlayer connection is provided with a conductive paste 9 in both side through holes 8 of a film insulator 7 made of a thermoplastic resin composition. The printed wiring board 6 is obtained by heat-sealing conductive foils on both surfaces thereof and forming a printed circuit 11 by a subtractive method.

The method for manufacturing a metal-based multilayer printed wiring board according to the second embodiment will be described in detail. First, a film-like insulator 7 made of a thermoplastic resin composition having the above-mentioned predetermined composition and thermal characteristics is formed by laser processing. A double-sided through hole 8 is formed, and a conductive paste 9 is filled therein to form a heat-fusible film 10 for interlayer connection of a laminated electric circuit. A conductor foil such as a roughened copper foil is heat-sealed by a vacuum heat press machine, and the printed circuit 11 is formed by removing the unnecessary portion by a subtractive method. The printed circuit 11 is formed on one side of a metal plate (or a chain line in FIG. 2C). The film-like wiring board 6 is superposed on the film-like insulator 7 on both sides as shown in FIG.

Film insulator 7 to be used as material of insulating layer 5
Is prepared by blending a polyarylketone resin and an amorphous polyetherimide resin, and preparing a resin having a predetermined crystallinity represented by the formula (I) by a method described later.

Formula (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35 When the conductive foil is heat-sealed to the film-like insulator 7, the glass transition point (Tg) of the thermoplastic resin composition is obtained. Is exceeded, but does not exceed the crystal melting peak temperature (Tc), that is, it is heated to a predetermined temperature range where amorphousness is maintained, and preferably, the thermoplastic resin composition maintains the characteristics represented by the formula (II). A film-shaped substrate to which a conductive foil is thermally fused is produced.

Formula (II): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 As a method of forming a conductive circuit on the conductive foil, a well-known subtractive method can be employed, but an additive method can also be employed. . Incidentally, as a specific example of the subtractive method, a dry film made of an ultraviolet curable resin is laminated on a copper foil, and then a pattern film formed with a cutout mold of a conductive circuit is exposed to ultraviolet light in a state where the pattern film is in close contact with the dry film. Exposure, then remove the pattern film and uncured dry film, perform etching with a ferric chloride solution to remove the copper foil in unnecessary portions of the conductive circuit, and then immerse in a sodium hydroxide solution The remaining dry film on the copper foil is removed to form a conductive circuit.

When the insulating layer 5 (film-like insulator 7) is superimposed on one or both sides of the metal plate 4 and the film-like wiring board 6 is further superimposed and heat-sealed at once, the thermoplastic layers constituting the respective layers are formed. The relationship between the heat of crystallization ΔHm of the resin composition and the heat of crystallization ΔHc generated by crystallization during heating is expressed by the formula (II)
Thermal fusion is performed to satisfy the relationship shown in (I).

Formula (III): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 In this manner, the thermoplastic resin composition is heated to around the crystal melting peak temperature (Tc) (for example, 230 to 250 ° C.). As a result, reliable heat fusion becomes possible and crystallization of the thermoplastic resin composition proceeds, so that a metal-based multilayer printed wiring board excellent in solder heat resistance can be manufactured.

In the present invention, the polyaryl ketone resin as the first component constituting the film-like insulator is a thermoplastic resin having an aromatic nucleus bond, an ether bond and a ketone bond in its structural unit, that is, phenyl ketone. And a phenyl ether.

Typical examples of the polyarylketone resin include polyetherketone, polyetheretherketone, and polyetherketoneketone. In the present invention, polyetheretherketone represented by the following formula 1 is used. It can be used as suitable.

[0036]

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The amorphous polyetherimide resin as the second component constituting the film-shaped insulator is an amorphous thermoplastic resin having an aromatic nucleus bond, an ether bond and an imide bond in its structural unit. In the present invention, a polyetherimide resin represented by the following formula 2 can be applied.

[0038]

Embedded image

The film-like insulator used in the present invention is composed of a composition obtained by blending the above two kinds of heat-resistant resins at a predetermined ratio, that is, the thermoplastic resin composition has a crystal melting peak temperature of 260 ° C. It is composed of 65 to 35% by weight of the above-mentioned polyarylketone resin and 35 to 65% by weight of the amorphous polyetherimide resin, and has a glass transition temperature of 150 to 2 as measured when the temperature is raised by differential scanning calorimetry.
30 ° C.

The reason for limiting the above blending ratio is that the polyarylketone resin is blended in a large amount exceeding 65% by weight or the blending ratio of the polyetherimide resin is less than 35% by weight. The crystallization speed is too fast and the crystallinity is too high, making it difficult to multi-layer the substrate by heat fusion, and increasing the volume shrinkage (dimensional change) due to the crystallization and the reliability of the circuit board. Is reduced.

When the content of the crystalline polyallyl ether ketone resin is less than 35% by weight or the content of the amorphous polyetherimide resin exceeds 65% by weight, the crystallization speed of the composition becomes too slow, and , And even if the crystal melting peak temperature is 260 ° C. or higher, the solder heat resistance decreases, which is not preferable.

The thermal characteristics of the film-like insulator before thermal fusion, which is an important control factor in the present invention, are represented by the heat of crystal fusion Δ
Hm and heat of crystallization ΔHc generated by crystallization during heating
Is to satisfy the relationship represented by the following formula (I).

Equation (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35 (ΔHm−ΔHc) / ΔHm
The measured values of two heats of transition appearing on the DSC curve when the temperature is raised by differential scanning calorimetry according to S K 7121 and JIS K 7122, the heat of crystal fusion ΔHm (J / g) and the heat of crystallization ΔHc (J / g) Is calculated from the value of

The value of the equation (ΔHm−ΔHc) / ΔHm also depends on the type and molecular weight of the raw material polymer and the compounding ratio of the composition, but greatly affects the molding and processing conditions of the film-shaped insulator. I do. That is, when the film is formed into a film, the raw material polymer is melted and then cooled immediately, whereby the value of the above formula can be reduced.
Further, these numerical values can be controlled by adjusting the heat history in each step. The heat history here refers to the temperature of the film-shaped insulator and the time during which the temperature has been reached, and the higher the temperature, the larger the numerical value tends to be.

Regarding the thermal characteristics of the conductor foil and the film-like insulator before thermal fusion, it is preferable that the value represented by the above formula (I) is as small as possible. 0.35 before thermal fusion with conductor foil
If the ratio exceeds, the crystallinity is already high, and the crystallization further proceeds during the heat-sealing for multi-layering, and the adhesive strength is undesirably reduced.

The relationship represented by the above formula (II) is related to the measurement after thermal fusion in a copper-clad laminate in which a conductor foil is thermally fused to the surface of a film-like insulator in the process of manufacturing a multilayer printed wiring board. It is based on

When the value represented by the formula (II) exceeds 0.5, the crystallinity is already high, and the crystallization proceeds further at the time of heat-sealing for multi-layering, whereby the adhesive strength decreases. Further, it is necessary to perform heat fusion with the conductor foil at a high temperature, which is not preferable in terms of manufacturing efficiency.

Then, the thermal characteristics of the film-like insulator after the thermal fusion after the multilayering satisfy the relation of the following formula (III).

Formula (III): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 Because the value of the above formula (III) is lower than 0.7, the crystallization of the insulating layer is insufficient. This is because solder heat resistance (usually 260 ° C.) cannot be maintained.

The film-like insulator used in the present invention generally has a thickness of 25 to 300 μm, and its production method is, for example, a known film-forming method such as an extrusion casting method using a T-die or a calendering method. What is necessary is just to employ | adopt and it is not necessary to employ | adopt a manufacturing method especially limited. In addition, it is preferable to employ the extrusion casting method using a T-die from the viewpoint of film forming property and stable productivity. The molding temperature of the extrusion casting method is appropriately adjusted depending on the flow characteristics and film forming characteristics of the composition, but is generally from the melting point of the composition to 430 ° C. or less.

The resin composition constituting the film-like insulator used in the present invention may contain other resins and other additives to such an extent that the effects of the present invention are not impaired. Examples include a heat stabilizer, an ultraviolet absorber, a light stabilizer, a colorant, a lubricant, a flame retardant, and an inorganic filler.
Further, the surface of the film-shaped insulator may be subjected to embossing or corona treatment for improving the handling properties and the like.

The metal plate used in the present invention is a well-known metal plate selected according to the purpose of improving heat dissipation and mechanical strength of a metal-based printed wiring board or a metal-based multilayer printed wiring board. For example, aluminum,
Examples include iron, copper, and zinc. The board thickness is 0.1 to 3.0
mm can be suitably used, and is usually 1.0 to 1.6.
mm.

When a metal plate having a roughened surface is used as a metal plate, the method of roughening (roughening) includes sand blasting, shot blasting, dry honing, chemical etching, electrolytic etching, and the like. And the like.

Examples of the conductor foil used in the present invention include metal foils having a thickness of about 8 to 70 μm, such as copper, gold, silver, aluminum, nickel, and tin. Among them, the metal foil to be applied is particularly preferably a copper foil whose surface has been subjected to a chemical conversion treatment such as a black oxidation treatment. The conductor foil is
In order to enhance the bonding effect, it is preferable to use a material whose contact surface (overlapping surface) with the film-shaped insulator is chemically or mechanically roughened in advance. The roughening method is the same as in the case of the above-described metal plate, and specific examples of the conductor foil having a roughened surface include a roughened copper foil that has been electrochemically treated when producing an electrolytic copper foil. Is mentioned.

When the conductor foil is superimposed on one or both surfaces of the film-like insulator and heat-sealed under heating and pressing conditions, for example, a hot pressing method, a heat laminating roll method, a method combining these methods, or other well-known methods Can be adopted.

[0056]

EXAMPLES AND COMPARATIVE EXAMPLES First, Production Examples 1 to 3 of a film insulator satisfying the conditions of the film insulator of the present invention.
The production methods of Reference Examples 1 and 2 and the physical properties thereof will be described below.

[Production Example 1 of Film Insulator] Polyetheretherketone resin (Victrex: PEE)
K381G) (in the following text or in Tables 1 and 2, P
Abbreviated as EEK. ) 60% by weight and a polyetherimide resin (manufactured by General Electric Company: Ultem-1)
000) (PEI in the following text or in Tables 1 and 2)
Abbreviated. ) 40% by weight was melt mixed. This mixed composition was extruded to produce a film insulator having a thickness of 25 μm.

[Production Example 2 of Film Insulator] Production Example 1
, A film-like insulator was produced in the same manner except that the mixing ratio of the mixed composition was 40% by weight of PEEK and 60% by weight of PEI.

[Production Example 3 of Film Insulator] Production Example 1
, A film-like insulator was produced in the same manner except that the mixing ratio of the mixed composition was 30% by weight of PEEK and 70% by weight of PEI.

[Reference Examples 1 and 2 of Film Insulator] In Production Example 1, the mixing ratio of the mixed composition was changed to PEEK100.
Each film-shaped insulator was manufactured in the same manner except that the weight% (Reference Example 1) or the PEI 100% by weight (Reference Example 2) was used.

In order to examine the physical properties of the film-like insulator obtained in the above Production Examples and Reference Examples, the following (1) and (2)
The following items were measured or calculated values were calculated from the measured values.
These results are summarized in Table 1.

(1) Glass transition temperature (° C.), crystallization temperature (° C.), crystal melting peak temperature (° C.) Heating using a 10 mg sample according to JIS K7121 using Perkin Elmer: DSC-7 Speed 1
Each of the above temperatures when the temperature was raised at 0 ° C./min was determined from a thermogram.

(2) (ΔHm−ΔHc) / ΔHm According to JIS K7122, 10 mg of a sample was used, and the heating rate was set to 1 using DSC-7 manufactured by Perkin Elmer.
The heat of crystal fusion ΔHm (J / g) and the heat of crystallization ΔHc (J / g) were determined from the thermogram when the temperature was raised at 0 ° C./min, and the value of the above equation was calculated.

[0064]

[Table 1]

Example 1 Thickness 25 obtained in Production Example 1
The film-shaped insulator having a thickness of μm was subjected to an opening process for an inner via hole using a laser, and the hole was filled with a conductive paste agent using a screen printer. After the conductive paste was sufficiently dried, an electrolytic copper foil having a 12 μm-thick electrochemically roughened surface was laminated on both surfaces of the film-like insulator, and 760 mm in a vacuum atmosphere.
Pressing temperature 200 ° C, pressing pressure 30kg / cm in Hg
^{2. A} double-sided copper-clad laminate was prepared by heat fusion under the conditions of a press time of 10 minutes.

The above-mentioned measurement test of (2) (ΔHm−ΔHc) / ΔHm was performed on the film-like insulator of the double-sided copper-clad laminate by the same method as described above.

The adhesive strength of the obtained double-sided copper-clad laminate was examined by the method (3) described later, and the results are shown in Table 2.

A circuit pattern was formed on the obtained double-sided copper-clad laminate by a subtractive method, and two wiring boards were formed by etching a conductive circuit. The thickness 2 obtained in Production Example 1 between the two wiring boards
A 5052 series (JISH-0012) aluminum plate (1.5 mm thick) is stacked as a core plate with two 5 μm film-shaped insulators sandwiched in between as shown in FIG. 2C, and pressed at 760 mmHg in a vacuum atmosphere. Temperature 220
° C., press pressure 30kg / cm ^2, and heat-sealed by a pin lamination method under the conditions of press time 20 minutes, a multilayer printed circuit board was manufactured in four layers.

The obtained aluminum-based multilayer printed wiring board was subjected to the above (2) (ΔHm−ΔHc) / ΔHm measurement test, and the adhesive strength between the copper foil circuit and the film-like insulator at room temperature was determined as follows. Check by the test method of (3), and check for delamination by a scanning electron microscope (see below).
(Method (5)), and the solder heat resistance was examined by the following test method (4). The results are shown in Table 2.

(3) Adhesive strength The peel strength of the copper foil was measured in accordance with the normal peel strength of JIS C6481, and the average value was measured in kg.
f / cm.

(4) Solder heat resistance According to the normal solder heat resistance of JIS C6481,
After floating in a solder bath at 60 ° C. for 10 seconds with the copper foil side of the test piece in contact with the solder bath, take out from the bath and allow it to cool to room temperature, and visually observe the presence or absence of swelling or peeling,
The quality was evaluated.

(5) The multilayer printed wiring board is embedded in epoxy resin, and a sample for section observation is prepared by a precision cutting machine.
The cut surface was observed with a scanning electron microscope (SEM), and the presence or absence of delamination between the film-like insulator and the conductive circuit made of copper foil was evaluated.

[0073]

[Table 2]

Example 2 In Example 1, the production temperature was set to 225 ° C. when a double-sided copper-clad laminate was produced by using Production Example 2 as a film-like insulator, and the heat was applied when a 4-layer substrate was produced. A four-layer printed wiring board was prepared in the same manner as in Example 1 except that the pressing conditions were changed to a temperature of 240 ° C. and a breath time to 30 minutes, and the evaluations of Tests (3) to (5) are shown in Table 2. Also described.

Comparative Example 1 A multilayer printed wiring board having four layers was produced in the same manner as in Example 1 except that the pressing temperature at the time of producing the double-sided copper-clad laminate was 215 ° C. Table 2 also shows the evaluations of the tests (3) to (5).

Comparative Example 2 The procedure of Example 2 was repeated, except that the pressing temperature of the multilayer printed wiring board having four layers was changed to 230 ° C. and the pressing time was changed to 10 minutes.
A multilayer printed wiring board having a plurality of layers was produced, and the evaluations of Tests (3) to (5) are also shown in Table 2.

COMPARATIVE EXAMPLE 3 In Example 1, the production temperature was changed to 240 ° C. and the press time was changed to 20 minutes when producing the double-sided copper-clad laminate using Production Example 3 as the film-like insulator. Except for the above, a four-layered multilayer printed wiring board was produced in the same manner as in Example 1, and tests (3) to (5) for the multilayer printed wiring board were performed.
Are also shown in Table 2.

As is clear from the results in Table 2, the adhesive strength of the double-sided copper-clad laminate of Example 1 was 0.7 kgf / 10
cm, which is (ΔHm−ΔHc) / ΔH
The value of m was also an appropriate value of 0.31. The value of (ΔHm−ΔHc) / ΔHm when laminating four multilayer printed wiring boards is 0.96, which is an appropriate value, and the adhesive strength is 1.5 kg.
It was a good value of f / 10 cm. As a result of the solder heat resistance test, no swelling or peeling was observed on the substrate, no delamination was observed even by SEM observation of the four-layered multilayer printed wiring board, and the resin wrapped around the circuit pattern (filling). Amount) was good, and generation of voids was not observed at all.

The adhesive strength of the double-sided copper-clad laminate of Example 2 was also a good value of 1.3 kgf / 10 cm, the result of the solder heat resistance test was good, and the S
No delamination was observed at all by EM observation, and the resin wrapping around the circuit pattern was good.

On the other hand, the four-layer printed wiring board of Comparative Example 1 was inferior in the adhesion between the layers, and the solder heat resistance was poor because swelling and peeling were observed.

The four-layer printed wiring board of Comparative Example 2
Although there was adhesion between the layers, the solder heat resistance was poor.

In Comparative Example 3, the adhesive strength between the copper foil and the film of the double-sided copper-clad laminate was as low as 0.2 kgf / 10 cm, and the circuit peeled off in the etching step.

[0083]

As described above, the metal-based printed wiring board according to the present invention heats the conductive foil through the insulating layer made of a thermoplastic resin composition having predetermined thermal characteristics on one or both sides of the metal plate. Since the printed circuit is formed with this conductive foil, it can be heat-fused to the conductive foil and metal base at a relatively low temperature, and is a metal base that is securely bonded and integrated and has solder heat resistance. There is an advantage that it is a printed wiring board.

Further, the metal-based multilayer printed wiring board of the present invention forms a film-shaped wiring board having a crystalline thermoplastic resin composition having predetermined thermal characteristics as an insulating layer, and the above-mentioned metal-based multilayer printed wiring board is formed on one or both sides of the metal plate. Since the film-like wiring board is integrated by thermal fusion via an insulating layer made of a thermoplastic resin composition, the thermoplastic resin composition of each layer exhibits excellent adhesive strength, and has four or more layers. Even with a metal-based multilayer printed wiring board, there is no delamination between layers, and the required solder heat resistance is exhibited.

Further, the insulating material is filled even between the fine wiring pitches at the time of thermal fusion of the respective layers, so that a metal-based multilayer printed wiring board having good insulating properties of the inner layer circuit formed with high wiring density can be obtained.

The method of manufacturing a multilayer printed wiring board of the present invention is a method of manufacturing a metal-based multilayer printed wiring board using a film-like insulator made of a crystalline thermoplastic resin having predetermined thermal characteristics. The embedding property of the inner layer circuit with high wiring density is improved, so that a circuit with high insulation reliability can be manufactured. In addition, the conductor foil and metal base laminated in multiple layers via the insulating layer are subjected to a single heating and pressing process. Therefore, since lamination can be surely performed by heat fusion, there is an advantage that the manufacturing method is efficient.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a main part of a metal-based printed wiring board.

FIG. 2 is an enlarged sectional view of a main part showing a manufacturing process of a metal-based multilayer printed wiring board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 4 Metal plate 2, 5 Insulating layer 3, 11 Printed circuit 6 Film-shaped wiring board 7 Film-shaped insulator 8 Double-sided through-hole 9 Conductive paste 10 Heat-fusible film for interlayer connection

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 3/46 H05K 3/46 S (72) Inventor Jun Takagi 5-8, Mitsuyacho, Nagahama-shi, Shiga Mitsubishi Resin Co., Ltd. Nagahama Plant (72) Inventor Koichiro Taniguchi 5-8 Miyayacho, Nagahama City, Shiga Prefecture Mitsubishi Plastics Co., Ltd. Nagahama Plant (72) Inventor Toshihiro Miya 1-1-1 Showacho, Kariya City, Aichi Prefecture Co., Ltd. Within DENSO (72) Inventor Makoto Toya 1-1-1 Showa-cho, Kariya-shi, Aichi F-term within DENSO Corporation (reference) 5E315 AA01 BB01 CC14 DD20 GG01 GG05 5E343 AA07 AA16 AA18 AA22 BB23 BB24 BB25 BB28 BB44 BB67 BB72 GG16 5E346 AA42 CC08 EE13 FF18 FF23 GG28 HH08 HH17

Claims (7)

[Claims] 1. A metal-based printed wiring board in which a conductive foil is heat-sealed on one or both sides of a metal plate via an insulating layer made of a thermoplastic resin composition to form a printed circuit with the conductive foil. The layer is composed of a thermoplastic resin composition containing 65 to 35% by weight of a polyarylketone resin having a crystal melting peak temperature of 260 ° C. or higher and 35 to 65% by weight of an amorphous polyetherimide resin. The composition has a glass transition temperature of 150 to 230 ° C. measured when heated by differential scanning calorimetry, and the relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during the temperature rise is represented by the following formula: The characteristic satisfying the relationship shown in (A) is calculated by the following formula.
A metal-based printed wiring board which is heat-sealed so as to satisfy the relationship shown in (B). Equation (A): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 Equation (B): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 2. The metal-based printed wiring board according to claim 1, wherein the conductive foil is a surface-roughened conductive foil. 3. The metal-based printed wiring board according to claim 1, wherein the metal plate is a surface-roughened metal plate. 4. A heat insulating film for interlayer connection of a laminated electric circuit is formed by forming a through hole on both sides of a film-shaped insulator made of a thermoplastic resin composition and filling a conductive paste in the through hole. Conductive foil is heat-sealed on both sides of this heat-sealing film for interlayer connection and a circuit is formed to provide a film-like wiring board, and on one or both sides of a metal plate via an insulating layer made of the thermoplastic resin composition. In a metal-based multilayer printed wiring board obtained by heat-sealing a film-shaped wiring board, the thermoplastic resin composition constituting the heat-sealed insulating layer and the heat-sealed film-shaped wiring board has a crystal melting peak temperature of 260. Polyarylketone resin 65 ° C or higher
35% by weight, and amorphous polyetherimide resin 35-6
This thermoplastic resin composition has a glass transition temperature of 150 to 230 ° C. measured when the temperature is raised by differential scanning calorimetry, a heat of crystal fusion ΔHm, and is generated by crystallization during the temperature rise. Is heat-fused so as to satisfy the relationship represented by the following formula (B) by heating a material having a relationship with the crystallization heat quantity ΔHc that satisfies the relationship represented by the following formula (A). A metal-based multilayer printed wiring board, characterized in that: Equation (A): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 Equation (B): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 5. The metal-based multilayer printed wiring board according to claim 4, wherein the conductive foil is a surface-roughened conductive foil. 6. The metal-based multilayer printed wiring board according to claim 4, wherein the metal plate is a metal plate having a roughened surface. 7. It contains 65 to 35% by weight of a polyaryl ketone resin having a crystal melting peak temperature of 260 ° C. or more and 35 to 65% by weight of an amorphous polyetherimide resin, and when heated by differential scanning calorimetry. The glass transition temperature to be measured is 150 to 230 ° C., and the relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during temperature rise is as follows:
(I) forming a film-like insulator made of a thermoplastic resin composition satisfying the relationship shown in (I), forming a double-sided through hole in the film-like insulator, and filling a conductive paste in the through-hole to form a laminated electric insulator. A heat-fusible film for interlayer connection of a circuit is formed, and the thermoplastic resin composition satisfies the relationship represented by the following formula (II) by superposing a conductive foil on both sides of the heat-fusible film for interlayer connection. After heat-sealing as described above, a circuit is formed on the conductive foil to provide a film-like wiring board, and the film-like wiring board is stacked on one or both sides of a metal plate via the film-like insulator to form each layer. A method for producing a metal-based multilayer printed wiring board, comprising: thermally bonding the resulting thermoplastic resin composition so as to satisfy the following relationship (III). Formula (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35 Formula (II): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 Formula (III): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7