JP2007326923A - Resin composition for adhering fluorine resin substrate and metal-clad laminate obtained by using the resin composition for adhering fluorine resin substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology prominently increasing adhesion of a fluorine resin substrate with a non-roughened metal foil by a simpler method and capable of forming fine pitch circuits. <P>SOLUTION: A resin composition for adhering a fluorine resin substrate, characterized by comprising 2-20 pts.wt polymer component soluble in a solvent and having one or more of hydroxy, carboxy and amino in a molecule as a functional group, and ≥50 pts.wt epoxy resin compound comprising an epoxy resin having ≥200°C boiling point and an amine-based epoxy resin curing agent having ≥200°C boiling point, is used as the resin composition for forming an adhesive layer for adhering a metal foil on a fluorine resin substrate. And, an adhesive for fluorine resin substrate and using the resin composition, a metal foil 4 with an adhesive layer in which a metal foil 2 and an adhesive layer 3 form a laminate structure, a copper-clad laminate using the fluorine resin substrate and a method for producing the laminate, are provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The invention according to the present application is obtained using a fluororesin substrate adhesive resin composition, a fluororesin substrate adhesive using the fluororesin substrate adhesive resin, and the fluororesin adhesive. The present invention relates to a metal-clad laminate, a printed wiring board, and a method for producing the metal-clad laminate. In particular, a resin composition for bonding a fluororesin base material, which is an adhesive raw material excellent in adhesiveness with a fluororesin base material, which is said to be difficult to obtain good adhesion even when pasted with a metal foil, The present invention relates to an adhesive for a fluororesin substrate and the like using the resin composition for bonding a fluororesin substrate.

  Electronic devices such as personal computers and mobile phones in recent years tend to increase the clock frequency at the GHz level in order to enable high-speed communication and high-speed computation. Correspondingly, printed wiring boards are also required to have low dielectric loss and low dielectric constant, such as dielectric characteristics, high frequency characteristics such as crosstalk characteristics, and other heat resistance and durability.

  In addition, in electronic devices such as satellite communication devices, due to the development of satellite broadcasting and satellite communication, in antennas, BS converters, etc., in the microwave (30 GHz or less) frequency band, millimeter waves (30 GHz to 300 GHz) used for higher-speed information transmission. ), A printed wiring board excellent in crosstalk characteristics and the like for high frequency circuits has been developed.

  In the above applications, it can be expected that the frequency band to be used will further shift to the high frequency band in the future. As the frequency band increases in this way, the dielectric characteristics are particularly important for the printed wiring board. In such a use, what used the fluororesin base material for the insulating layer of the printed wiring board has been used.

  For example, Patent Document 1 includes a dielectric obtained by combining a glass cloth having a low dielectric constant and a low dielectric loss tangent and a fluororesin, and an electrolytic copper foil formed on at least one main surface of the dielectric. A fluororesin copper-clad laminate having a dielectric constant of 2.3 (12 GHz) or lower and a dielectric loss tangent of 0.001 (12 GHz) or lower is disclosed. From this document, it can be understood that the fluororesin base material has excellent dielectric characteristics and is extremely useful as an insulating layer constituting material of a printed wiring board in a high frequency region.

  However, when a fluororesin base material is used, there is a drawback that the adhesion between the fluororesin base material and the metal foil is weak. In particular, the adhesion after moisture absorption tended to be weakened.

  In order to improve the adhesion between the fluororesin substrate and the metal foil, Patent Document 2 provides a fluororesin adhesion impregnation layer between a fluororesin impregnation layer in which a glass cloth is impregnated with a fluororesin and a metal foil. A printed wiring board is disclosed. The fluororesin adhesion impregnated layer at this time is used to improve the adhesion between the metal foil and the fluororesin impregnated layer immediately below the metal foil by the anchor effect resulting from the resin characteristics, and to enhance the peel strength. The fluororesin adhesion impregnation layer preferably uses PTFE as the fluororesin of the fluororesin impregnation layer and PFA as the fluororesin of the fluororesin adhesion impregnation layer. That is, the fluororesin is combined with both the base material and the adhesive layer.

  Patent Document 3 discloses at least one selected from polyallyl sulfone, aromatic polysulfide, and aromatic polyether for the purpose of providing a wiring board that can be used with high reliability even under high temperature and high humidity conditions. It is disclosed that a fluororesin composition characterized by comprising at least one kind of thermoplastic resin and fluororesin is used as an insulating layer constituting material of a printed wiring board.

  Further, Patent Document 4 does not improve the adhesion between the fluororesin substrate and the metal foil, but in order to improve the adhesion between the fluororesin substrate and the conductor formed by the screen printing method, The surface for forming the conductor wiring is subjected to a roughening treatment, a plasma treatment, a roughening treatment, a plasma treatment, or a roughening treatment and then a metal film coating formation treatment by a sputtering method. A printed wiring board characterized by any one surface treatment is disclosed.

JP 2002-307611 A WO01 / 003478 publication JP 11-199738 A WO2003 / 103352

  However, printed wiring boards obtained from fluororesin copper-clad laminates have been required to have even finer pitch circuits in order to achieve multi-functionality and miniaturization of electronic devices if their use is difficult. .

  And the copper foil manufactured by the electrolytic method or the rolling method has been widely used for the circuit formation. This copper foil is usually subjected to a roughening treatment, an antirust treatment, and a silane coupling agent treatment on the bonding surface. Depending on the level of the roughening treatment at this time, it is difficult to form a required fine pitch circuit by an etching method. In addition, if the adhesion between the fluororesin substrate and the copper foil is low, the chemical resistance performance and the moisture absorption resistance against the etching solution and the like are significantly deteriorated, so that it is impossible to form a fine pitch circuit. In recent years, a copper-clad laminate using an FR-4 base material has been attempted to form a fine pitch circuit, which has been impossible in the past, using a non-roughened copper foil. In contrast, conventional fluororesin substrates have low adhesion between the fluororesin substrate and the metal foil, so almost no adhesion can be obtained when using a non-roughened metal foil. I couldn't even do it.

  In the methods disclosed in Patent Document 2 and Patent Document 3, sufficient adhesion between the fluororesin substrate and the non-roughened copper foil cannot be obtained, and there is a certain limit. As a result, when a heat shock was applied, peeling (delamination phenomenon) occurred between the fluororesin substrate and the circuit formed of the non-roughened copper foil.

  Therefore, in the market, a technique capable of remarkably improving the adhesion between the fluororesin base material and the non-roughened metal foil by a simpler method and forming a fine pitch circuit has been desired.

  Therefore, as a result of earnest research, the inventors of the present invention formed a bonding interface between the fluororesin base material and the metal foil using the resin composition described below, and thereby the circuit of the fluororesin-based printed wiring board. The peel strength was dramatically improved, and it became possible to use a non-roughened metal foil. Therefore, the metal foil described below mainly means a non-roughened metal foil. The present invention will be described below.

Resin composition for fluororesin substrate adhesion: The resin composition for adhesion of a fluororesin substrate according to the present invention is a resin composition for forming an adhesive layer for bonding a metal foil to a fluororesin substrate. The resin composition is soluble in a solvent and has 2 to 50 parts by weight of a polymer component having one or more of hydroxyl group, carboxyl group and amino group in the molecule as a functional group, and having a boiling point of 200 ° C. or more. It contains 50 parts by weight or more of an epoxy resin blend composed of an epoxy resin and an amine epoxy resin curing agent having a boiling point of 200 ° C. or higher.

  In the resin composition for bonding a fluororesin substrate according to the present invention, the polymer component is one selected from the group consisting of a polyvinyl acetal resin, a phenoxy resin, an aromatic polyamide resin, a polyether sulfone resin, and a polyamideimide resin. It is preferable to mix two or more kinds.

  In the fluororesin substrate adhesive resin composition according to the present invention, the epoxy resin having a boiling point of 200 ° C. or higher is bisphenol A type epoxy resin, bisphenol F type epoxy resin, rubber-modified bisphenol A type epoxy resin, biphenyl type epoxy. It is preferable to use one or a mixture of two or more selected from the group of resins.

  In the fluororesin substrate adhesive resin composition according to the present invention, the amine-based epoxy resin curing agent includes aromatic polyamines, polyamides, and amines obtained by polymerizing or condensing these with epoxy resins or polycarboxylic acids. It is preferable to use one or more selected from the group of adduct bodies.

Adhesive for fluororesin substrate: The adhesive for fluororesin substrate according to the present invention is a resin adhesive used for bonding a metal foil to a fluororesin substrate, and the resin composition for adhering the fluororesin substrate It is obtained by adding an organic solvent to the product and mixing it.

  The adhesive for a fluororesin substrate according to the present invention uses any one solvent of methyl ethyl ketone, cyclopentanone, dimethylformamide, dimethylacetamide, N-methylpyrrolidone or a mixed solvent thereof as the organic solvent. Is preferred.

Metal foil with an adhesive layer: The metal foil with an adhesive layer according to the present invention is a metal foil with an adhesive layer provided on the surface of the metal foil with an adhesive layer to the base material, and the adhesive layer is a resin adhesive for a fluororesin substrate. It is formed using.

  In the metal foil with an adhesive layer according to the present invention, the adhesive layer is preferably a semi-cured resin layer having a thickness of 0.5 μm to 3 μm.

  In the metal foil with an adhesive layer according to the present invention, the adhesive layer of the metal foil with an adhesive layer has a characteristic that the resin flow is within 5% when measured according to MIL-P-13949G in the MIL standard. It is preferable.

  Furthermore, in the metal foil with an adhesive layer according to the present invention, the metal foil is copper foil, nickel foil, tin foil, gold foil, silver foil, platinum foil, iron foil, cobalt foil, copper alloy foil, nickel alloy foil, tin alloy. It is preferable to use any of foil, gold alloy foil, silver alloy foil, platinum alloy foil, iron alloy foil, and cobalt alloy foil.

Metal-clad laminate: The metal-clad laminate according to the present invention is a metal-clad laminate obtained by laminating a metal layer on the surface of a fluororesin substrate via an adhesive layer, and the adhesive layer has the resin composition described above. It is characterized by including things.

  The metal-clad laminate according to the present invention is a metal-clad laminate obtained by attaching a metal layer to the surface of a fluororesin substrate via an adhesive layer, and the adhesive layer is used for the fluororesin substrate. It is formed using an adhesive.

Printed wiring board: The printed wiring board according to the present invention is obtained by etching the metal foil of the metal-clad laminate.

Method for producing metal-clad laminate: The method for producing a metal-clad laminate according to the present invention is characterized by going through the following steps A-1 to C-1, and for convenience of explanation, This is referred to as “first manufacturing method”.

Step A-1: A step of applying an activation treatment to the bonding surface of the fluororesin substrate with the metal foil.
Step B-1: A fluororesin substrate adhesive is prepared, and this fluororesin substrate adhesive is applied to the surface of the metal foil and dried, so that the thickness of the metal foil is 0.5 μm to 3 μm. The process of manufacturing metal foil with an adhesive layer by forming a semi-cured resin layer.
Step C-1: A metal-clad laminate is obtained by hot-pressing the adhesive layer surface of the metal foil with an adhesive layer in contact with the laminated surface subjected to the activation treatment of the fluororesin substrate and laminating it. Process.

  Moreover, the manufacturing method of the metal-clad laminated board which concerns on this invention can also employ | adopt what is characterized by passing through the following process A-2-the process C-2. For convenience of explanation, it is hereinafter referred to as “second manufacturing method”.

Step A-2: A step of performing an activation treatment on the bonding surface of the fluororesin base material with the metal foil.
Step B-2: An adhesive for a fluororesin substrate is prepared, and the adhesive for a fluororesin substrate is applied to the surface of the releasable plastic film and dried, so that the releasable plastic film and thickness A step of producing an adhesive layer with a releasable plastic film in which a semi-cured resin layer of 0.5 μm to 3 μm is in a laminated state.
Step C-2: The semi-cured resin layer of the adhesive layer with a releasable plastic film is brought into contact with the laminated surface subjected to the activation treatment of the fluororesin base material, and is temporarily bonded to each other. The process of peeling off and leaving the semi-cured resin layer on the surface of the fluororesin substrate.
Step D-2: A step of forming a metal-clad laminate by laminating a metal foil on the surface of the semi-cured resin layer provided on the surface of the fluororesin substrate in Step C-2 and hot pressing it.

  Furthermore, the manufacturing method of the metal clad laminated board which concerns on this invention can also employ | adopt what is characterized by passing through the following process A-3-process C-3. For convenience of explanation, it is hereinafter referred to as “third manufacturing method”.

Step A-3: A step of performing activation treatment on the bonding surface of the metal foil of the fluororesin base material.
Process B-3: The process of preparing the adhesive for fluororesin base materials.
Step C-3: Applying the adhesive for the fluororesin substrate prepared in Step B-3 to the activated surface of the fluororesin substrate and drying it, semi-curing 0.5 μm to 3 μm in thickness Forming a resin layer;
Step D-3: Step of forming a metal-clad laminate by laminating a metal foil on the surface of the semi-cured resin layer provided on the surface of the fluororesin substrate in Step C-3 and hot pressing it.

  In the method for producing a metal-clad laminate as described above, it is preferable that the activation treatment is any one of a roughening treatment, a plasma treatment, or a composite treatment combining these.

  The resin composition for bonding a fluororesin base material according to the present invention is suitable for forming an adhesive layer when a non-roughened metal foil is laminated to a fluororesin base material. It is possible to remarkably improve the adhesion to the metal foil and to effectively prevent the delamination phenomenon of the circuit when subjected to a heat shock. When an adhesive layer is to be formed with this fluororesin substrate adhesive resin composition, an organic solvent is added to the fluororesin substrate resin composition to provide an optimal resin flow suitable for layer formation. The resin solid content can be obtained and used as an adhesive for a fluororesin substrate.

  And it is also easy to form an adhesive layer on the surface of the metal foil using the resin adhesive for a fluororesin substrate, and it becomes possible to provide a metal foil with an adhesive layer for a fluororesin substrate. At this time, the best adhesiveness with respect to a fluororesin base material can be obtained by making the thickness of the said adhesive layer into the semi-hardened resin layer of 0.5 micrometer-3 micrometers. In addition, as the metal foil at this time, various non-roughened metal foils can be used, and the present invention is not limited to printed wiring board applications and can be widely used.

  By using the above resin composition for bonding a fluororesin substrate, a resin adhesive for a fluororesin substrate, and a metal foil with an adhesive layer for a fluororesin substrate, the adhesion between the fluororesin substrate and the metal layer is excellent. A metal-clad laminate can be provided. Therefore, by using this metal-clad laminate, it is possible to provide a high-quality printed wiring board.

  Furthermore, in the method for producing a metal-clad laminate according to the present invention, since the adhesive layer is interposed, the press temperature during hot pressing can be lowered, and the production cost can be reduced. In addition, the adhesiveness between the fluororesin substrate and the metal layer can be more stably improved by applying an activation treatment to the bonding surface of the metal foil of the fluororesin substrate in advance.

  Hereinafter, embodiments relating to the present invention will be described. In the description, each item will be described separately.

Form of resin composition for fluororesin substrate adhesion: The resin composition for fluororesin substrate adhesion according to the present invention is (1) soluble in a solvent and has a hydroxyl group, carboxyl group, amino group as a functional group in the molecule. 2 parts by weight to 50 parts by weight of a polymer component having one kind or two or more kinds, (2) 50 weights of an epoxy resin composition comprising an epoxy resin having a boiling point of 200 ° C. or higher and an amine epoxy resin curing agent having a boiling point of 200 ° C. or higher Part or more. Here, it is a case where the sum total of the said polymer component and an epoxy resin compound is 100 weight part.

  Here, “a polymer component that is soluble in a solvent and has one or more of a hydroxyl group, a carboxyl group, and an amino group in a molecule as a functional group” (hereinafter simply referred to as “polymer component”) means polyvinyl. It is preferable to use one or a mixture of two or more selected from the group of acetal resins, phenoxy resins, aromatic polyamide resins, polyether sulfone resins, and polyamideimide resins. The polymer component here is required to be soluble in a solvent. If not possible, it will be difficult to adjust the solid content using a solvent. And when this polymer component is less than 2 weight part, since the hardness after press molding of a copper clad laminated board is high and it becomes weak, toughness cannot be obtained. On the other hand, when the polymer component exceeds 50 parts by weight, the heat resistance is lowered, and it becomes impossible to withstand the press molding temperature of the copper clad laminate, thereby causing resin deterioration. More preferably, the polymer component is 2 to 30 parts by weight. The heat resistance and flexibility as the cured resin are the best.

  “Epoxy resin having a boiling point of 200 ° C. or higher” is a mixture of one or more selected from the group of bisphenol A type epoxy resin, bisphenol F type epoxy resin, rubber-modified bisphenol A type epoxy resin, and biphenyl type epoxy resin. It is preferable to use it. By using a linear (bifunctional) epoxy resin, the adhesion between the fluororesin substrate and the metal foil can be increased. Therefore, the total of “epoxy resin having a boiling point of 200 ° C. or higher” and “amine-based epoxy resin curing agent having a boiling point of 200 ° C. or higher”, which is the main component of this resin composition, is referred to as an epoxy resin compound, which is 50 parts by weight or more. It is preferable that More preferably, it is used at a blending ratio of 50 to 80 parts by weight. Therefore, when the epoxy resin compound is less than 50 parts by weight, the adhesion between the fluororesin substrate and the metal foil cannot be sufficiently improved. It becomes high, and the range of the resin flow described later cannot be maintained.

  And as an epoxy resin curing agent, if only for the purpose of curing, dicyandiamide, imidazoles, amines such as aromatic amines, phenols such as bisphenol A and brominated bisphenol A, phenol novolac resins and cresols Any curing agent such as novolaks such as novolak resins and acid anhydrides such as phthalic anhydride can be used. However, it is most preferable to use an amine epoxy resin curing agent having a boiling point of 200 ° C. or higher from the viewpoint of significantly improving the adhesion between the fluororesin substrate and the metal foil. If the press molding temperature is around 180 ° C. and the boiling point of the curing agent is near the press molding temperature, the epoxy resin curing agent will boil due to the press molding, and bubbles are likely to be generated in the cured insulating resin layer. The most stable adhesion can be obtained when an amine-based epoxy resin curing agent is used to form an adhesive layer between the fluororesin substrate and the metal foil. That is, the “amine epoxy resin curing agent having a boiling point of 200 ° C. or more” is selected from the group of aromatic polyamines, polyamides, and amine adducts obtained by polymerizing or condensing these with epoxy resins or polyvalent carboxylic acids. The case where one kind or two kinds or more are used. More specifically, 4,4′-diaminodiphenylenesulfone, 3,3′-diaminodiphenylenesulfone, 4,4-diaminodiphenylel, 2,2-bis [4- It is preferable to use either (4-aminophenoxy) phenyl] propane or bis [4- (4-aminophenoxy) phenyl] sulfone. Moreover, since the addition amount with respect to the epoxy resin of the said amine epoxy resin hardening | curing agent is derived from each equivalent naturally, it thinks that it is not necessary to specify the compounding ratio strictly strictly. Therefore, in this invention, the addition amount of a hardening | curing agent is not specifically limited.

  It is also preferable to use a curing accelerator that is added in an appropriate amount as required. The curing accelerator referred to here is a tertiary amine, imidazole, urea curing accelerator or the like. In the present invention, the mixing ratio of the curing accelerator is not particularly limited. This is because the amount of the hardening accelerator can be arbitrarily determined by the manufacturer in consideration of heating conditions during press working.

  And it is also preferable to add rubber-like resin to the resin composition said to this invention. The rubber resin referred to here is described as a concept including natural rubber and synthetic rubber, and the latter synthetic rubber includes styrene-butadiene rubber, butadiene rubber, butyl rubber, ethylene-propylene rubber and the like. Furthermore, when heat resistance is required, it is also useful to selectively use heat-resistant synthetic rubbers such as nitrile rubber, chloroprene rubber, silicon rubber, urethane rubber. Regarding these rubber resins, it is desirable to have various functional groups at both ends so as to react with the polymer component to form a copolymer.

  Furthermore, it is also preferable to add the above-mentioned high-molecular polymer crosslinking agent as necessary. For example, when a polyvinyl acetal resin is used as the polymer, a urethane resin is used as a cross-linking material.

  If all the components of the resin composition described above are included, when the resin composition is 100 parts by weight, the epoxy resin is 50 parts by weight to 80 parts by weight, and the curing agent is 1 part by weight to 15 parts by weight. , 0.01 to 1.0 part by weight of the curing accelerator, 2 to 50 parts by weight of the polymer component, 1 to 5 parts by weight of the crosslinking agent, and 1 to 10 parts by weight of the rubber resin. It is preferable to adopt a composition in the range. As long as it is included in this composition range, good adhesion between the fluororesin substrate and the metal foil is maintained, and variation in product adhesion is reduced.

Form of Adhesive for Fluororesin Substrate: Generally, it is difficult to use the resin composition for adhering a fluororesin substrate as it is to form an adhesive layer. Therefore, an organic solvent is added to and mixed with the resin composition for bonding a fluororesin base material and used as an adhesive for a fluororesin base material. In such a case, it is preferable to adjust the resin solid content to 10 wt% to 40 wt%. When the resin solid content is less than 10 wt%, the viscosity is too low, and even if a resin film for forming an adhesive layer is formed, it flows immediately after coating and it is difficult to ensure film thickness uniformity. On the other hand, when the resin solid content exceeds 40 wt%, the viscosity is high and it is difficult to form a thin resin film.

  As the organic solvent at this time, it is preferable to use any one of methyl ethyl ketone, cyclopentanone, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, or a mixed solvent thereof. The solvent said here has selected the thing which can melt | dissolve the said resin composition. However, when methyl ethyl ketone and / or cyclopentanone is used as a solvent, it is easy to efficiently volatilize and remove by heat at the time of press working in the production of a metal laminate, and the purification treatment of volatile gas is easy. The resin solution viscosity suitable for resin film formation can be easily adjusted. In the case of a mixed solvent of methyl ethyl ketone and cyclopentanone, the mixing ratio is not particularly limited, but it is preferable to use methyl ethyl ketone as a co-solvent for cyclopentanone because the speed of devolatilization is increased.

  However, in the case of a polymer component that is difficult to dissolve in methyl ethyl ketone or cyclopentanone, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, or the like is used as a solvent. In particular, when a solvent obtained by mixing a plurality of these solvents is used, the quality stability of the obtained resin solution tends to be ensured for a long period of time. Even when such a solvent is used, the resin solid content of the resin solution is preferably 10 wt% to 40 wt% for the same reason.

Form of Metal Foil with Adhesive Layer: As shown in FIG. 1, the metal foil with an adhesive layer according to the present invention is a metal foil 4 with an adhesive layer provided with an adhesive layer 3 for a substrate on the surface of the metal foil 2. The adhesive layer is formed by using the resin adhesive for a fluororesin substrate. This forming method will be described later.

In the metal foil with an adhesive layer according to the present invention, the adhesive layer is a semi-cured resin layer having a thickness of 0.5 μm to 3 μm. Here, if it is not a semi-cured resin layer, it will not be reflowed by hot pressing, so that the fluororesin substrate and the metal foil cannot be bonded together. The reason why the thin resin layer is formed in this way is to surely create a state in which the resin flow described below hardly occurs during press working. When the thickness of the adhesive layer is less than 0.5 μm, it is difficult to make the thickness uniform, and it is difficult to leave a resin layer having a uniform thickness between the fluororesin substrate and the metal foil. In the surface of a single metal-clad laminate having a workpiece size, the peeling strength varies greatly. On the other hand, when the thickness of the adhesive layer exceeds 3 μm, good electrical characteristics of the fluororesin substrate are deteriorated. In addition, the thickness of this adhesive layer is a converted thickness when it is considered that the resin is applied to a complete plane per 1 m ² .

In the metal foil with an adhesive layer according to the present invention, the adhesive layer of the metal foil with an adhesive layer has a characteristic that the resin flow is within 5% when measured according to MIL-P-13949G in the MIL standard. It is preferable. If this resin flow is not within 5%, good adhesion between the fluororesin substrate and the metal foil cannot be obtained. In addition, although it does not prescribe | regulate especially regarding a minimum, it is about 1%. Regarding the resin flow, the thickness of the adhesive layer and the resin solid content of the resin adhesive for the fluororesin substrate used when forming the adhesive layer are factors that determine the characteristics. Of course it is important. Usually, when laminating a metal foil and a fluororesin base material, air may be jammed at the interface. Therefore, taking the case of producing a copper clad laminate as an example, a resin flow of about 5 mm to 15 mm from the end is intentionally caused by a 1 m ² size copper clad laminate also serving as the air vent. However, in the case of the adhesive layer used in the present invention, the fact that this resin flow hardly occurs is an important factor in securing good adhesion between the fluororesin substrate and the metal foil.

In this specification, the resin flow is determined by a value measured according to MIL-standard MIL-P-13949G. That is, in order to ensure the measurement accuracy of the resin flow, the adhesive layer is intentionally formed on the surface of the electrolytic copper foil with a thickness of 40 μm, and four 10 cm square samples are manufactured. Then, the four 10 cm square samples were stacked and bonded together under the conditions of a press temperature of 171 ° C., a press pressure of 14 kgf / cm ² , and a press time of 10 minutes, and the resin flow at that time was calculated according to Equation 1. In addition, when using a normal prepreg and the resin flow of a normal copper foil with resin (40 μm thick resin layer) is about 20%.

  Furthermore, in the metal foil with an adhesive layer according to the present invention, the metal foil is copper foil, nickel foil, tin foil, gold foil, silver foil, platinum foil, iron foil, cobalt foil, copper alloy foil, nickel alloy foil, tin alloy. It is preferable to use any of foil, gold alloy foil, silver alloy foil, platinum alloy foil, iron alloy foil, and cobalt alloy foil. That is, it describes with the concept of all the metal foils which can be used for an electronic material use. And all of the said metal foil may be obtained by an electrolytic method, obtained by a rolling method, or obtained by a physical vapor deposition method regardless of the production method. Moreover, there is no special limitation regarding the thickness.

  However, it is possible to further improve the adhesion by subjecting the surface of the metal foil to rust prevention treatment, silane coupling agent treatment, and the like. Therefore, the metal foil used in the present invention is intended for the one in which the roughening treatment is omitted. However, there is no problem in using a metal foil that has been subjected to roughening treatment. The roughening treatment is a method in which fine metal particles are adhered and formed on the surface of the metal foil, or the surface of the metal foil is chemically treated to form an uneven shape. . In particular, the generally well-known roughening treatment is a roughening treatment performed by depositing and forming fine copper grains applied to the electrolytic copper foil and the rolled copper foil.

  The antirust treatment referred to here is appropriately selected and used according to the type of the fluororesin base material, and there is no particular limitation. As the rust prevention treatment, any of organic rust prevention using benzotriazole, imidazole or the like, or inorganic rust prevention using zinc, chromate, zinc alloy, nickel alloy or the like may be adopted. In the case of organic rust prevention, techniques such as dip coating, shower ring coating, and electrodeposition of an organic rust preventive agent can be employed. In the case of inorganic rust prevention, it is possible to use a method of depositing a rust-preventive element on the surface of the copper foil by electrolysis or other so-called substitution deposition method. In the drawing, the rust-proofing layer is omitted without being particularly described.

  The silane coupling agent treatment is generally performed using one or more of an amino silane coupling agent, an epoxy silane coupling agent, and a mercapto silane coupling agent. In the silane coupling agent treatment, various types such as an olefin functional silane, an acrylic functional silane, the most common epoxy functional silane coupling agent as a silane coupling agent can be used. However, it is particularly preferable to use an amino-functional silane coupling agent or a mercapto-functional silane coupling agent because the adhesion between the fluororesin substrate and the metal foil can be further increased. It has been said that the higher the peel strength of a printed wiring board circuit, the better. However, in recent years, circuit peeling during etching has been eliminated by improving the precision of etching technology, and a method for handling printed wiring boards in the printed wiring board industry has been established, and the problem of disconnection peeling caused by accidentally hooking a circuit has been solved. It was. Therefore, in recent years, it is said that actual use is possible if the peel strength is at least 0.8 kgf / cm or more, and it is said that there is no problem if it is 1.0 kgf / cm or more.

  These silane coupling agents will be described more specifically. Vinyltrimethoxysilane, vinylphenyltrimethoxylane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, mainly for coupling agents similar to those used for prepreg glass cloth for printed wiring boards 4-glycidylbutyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-3- (4- (3-aminopropoxy) ptoxy) propyl-3 -Aminopropyltrimethoxysilane, imidazolesilane, triazinesilane, γ-mercaptopropyltrimethoxysilane, etc. can be used.

  The method for treating the silane coupling agent is not particularly limited, such as a commonly used dipping method, showering method, spraying method, and the like. In accordance with the process design, a method that allows the metal foil and the solution containing the silane coupling agent to be brought into contact and adsorbed most uniformly may be arbitrarily employed. The silane coupling agent is used at a temperature of room temperature by dissolving 0.5 to 10 g / l in water as a solvent. When the silane coupling agent concentration is less than 0.5 g / l, the adsorption rate of the silane coupling agent is slow, which is not suitable for general commercial profitability, and the adsorption is not uniform. Moreover, even if the concentration exceeds 10 g / l, the adsorption rate is not particularly increased, which is uneconomical. In the drawings, the silane coupling agent-treated layer is not particularly described and is omitted.

Form of metal-clad laminate: The metal-clad laminate according to the present invention is a metal-clad laminate obtained by attaching a metal layer to the surface of a fluororesin substrate via an adhesive layer, wherein the adhesive layer is the resin described above. It is characterized by including a composition. Further, the adhesive layer is formed using the fluororesin substrate adhesive. FIG. 2 shows a cross-sectional configuration of the metal-clad laminate according to the present invention. 2 (a) shows a single-sided metal-clad laminate 1a, FIG. 2 (b) shows a double-sided metal-clad laminate 1b, and FIG. 2 (c) shows a 4-layer metal-clad laminate with an inner layer circuit 9 inside. 1c is shown. Therefore, the metal-clad laminate according to the present invention is a state in which the metal foil 2 is bonded to the outer layer regardless of the layer configuration, and the inner layer includes the fluororesin base layer 5 and is a metal A laminate having a configuration in which the adhesive layer 3 is provided between the foil 2 and the fluororesin substrate layer 5 is referred to.

  Here, FIG. 2C briefly describes a method for manufacturing the four-layer metal-clad laminate 1c having the inner layer circuit 9 therein. For example, the double-sided printed wiring board 21 is formed by etching the metal layers on both sides of the double-sided metal-clad laminate 1b shown in FIG. Then, using the two double-sided printed wiring boards 21 and the prepregs 22 such as FR-4, etc., the four-layer metal-clad laminate 1c is obtained by laminating as shown in FIG. Further, using two double-sided printed wiring boards 21 and a fluororesin substrate 5 provided with an adhesive layer 3 using a fluororesin material adhesive according to the present invention on both sides, as shown in FIG. A four-layer metal-clad laminate 1c is obtained by hot pressing.

  The fluororesin base material referred to here is PTFE (polytetrafluoroethylene (tetrafluoroethylene)), PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer), FEP (tetrafluoroethylene / hexafluoropropylene copolymer). Polymer (4.6 fluoride)), ETFE (tetrafluoroethylene / ethylene copolymer), PVDF (polyvinylidene fluoride (difluoride)), PCTFE (polychlorotrifluoroethylene (trifluoride)), In addition, a group using a fluororesin composed of at least one thermoplastic resin and fluororesin selected from polyallyl sulfone, aromatic polysulfide and aromatic polyether as disclosed in Patent Document 3 It is a material, and even if it contains skeletal materials such as glass cloth It does not matter. Moreover, there is no special limitation also about the thickness of this fluororesin base material.

Form of printed wiring board: The printed wiring board according to the present invention is obtained by etching the metal foil of the metal-clad laminate. The etching process at this time is not particularly limited, but an etching resist layer is provided on the surface of the metal foil, the etching pattern is exposed and developed, a resist pattern is formed, and an etching solution that can dissolve the constituent metal components of the metal foil. It is common to perform circuit etching.

Form of manufacturing method of metal-clad laminate: A first method of manufacturing a metal-clad laminate according to the present invention will be described. Hereinafter, step A-1 to step C-1 will be sequentially described.

Step A-1: In this step, an activation treatment is performed on the bonding surface of the metal foil of the fluororesin base material. The activation treatment referred to here is performed in order to improve the adhesion between the fluororesin substrate and the adhesive layer, and as a result, improve the adhesion of the metal foil to the surface of the fluororesin substrate. More specifically, this activation process is a roughening process, a plasma process, or a combined process combining them. For the roughening treatment of the fluororesin substrate, a wet or dry blast method, a wet etching method, a dry etching method, or the like can be used. In particular, a wet etching roughening process performed using a chemical technique often employs a technique called sodium etching. The roughened surface formed by this roughening treatment preferably has an average roughness (Ra) of 20 nm to 100 nm. When this average roughness (Ra) is less than 20 nm, the adhesion between the fluororesin substrate and the adhesive layer cannot be improved. On the other hand, even if the average roughness (Ra) exceeds 100 nm, the effect of improving the adhesion between the fluororesin substrate and the adhesive layer due to the roughening does not increase further.

The plasma treatment is a treatment in which a plasma stream is generated with an inert gas such as nitrogen gas or argon gas, and the surface of the fluororesin substrate is brought into contact with the plasma stream. The inert gas is decompressed and introduced into the atmosphere, a pair of flat plate electrodes are arranged in parallel, a voltage is applied between the electrodes to generate a plasma stream, and a fluororesin substrate is placed in the plasma stream. Put in and process for a certain time. Alternatively, a plasma stream is generated between the high-frequency electrodes and the like, and a fluororesin substrate is placed in the plasma stream and processed for a certain period of time. Is no particular limitation to the plasma treatment conditions at this time, but the power density is calculated from the input power (W) and the electrode area as ^{(cm 2) (W / cm} 2) is 0.05W ^/ cm 2 ~1W ^/ cm Assuming ² , a processing time of about 30 seconds to 1 minute is adopted. This is because even if this plasma treatment time is unnecessarily long, the adhesion between the fluororesin substrate and the metal foil is not significantly improved.

  Moreover, when performing the combined process which combined the said roughening process and the plasma process, any process may be performed first. FIG. 5A conceptually shows the activated fluororesin substrate 5.

Step B-1: In this step, an adhesive for a fluororesin substrate is prepared, and this adhesive for a fluororesin substrate is applied to the surface of the metal foil and dried, so that the surface of the metal foil has a thickness of 0.5 μm. A metal foil with an adhesive layer is produced by forming a semi-cured resin layer having a thickness of ˜3 μm. The preparation of the fluororesin substrate adhesive is as described above.

  And by apply | coating this adhesive for fluororesin base materials to the surface of the metal foil 2, and drying, the semi-hardened resin layer (in the drawing, " By forming the adhesive layer 3 ", the metal foil 4 with an adhesive layer shown in FIG. 5B is manufactured.

Step C-1: In this step, as shown in FIG. 5 (c), the adhesive layer obtained in Step B-1 is applied to the bonded surface subjected to the activation treatment of the fluororesin substrate in Step A-1. The metal-clad laminate 1a shown in FIG. 5 (d) is obtained by laminating the adhesive layer 3 of the attached metal foil 4 in contact with each other and performing hot press molding. There is no particular limitation on the hot pressing conditions at this time. However, in the case of the manufacturing method according to the present invention, a press temperature of about 260 ° C. to 400 ° C. has been adopted for press processing using a conventional fluororesin substrate, but around 200 ° C. (190 ° C. to 220 ° C.). Can be pressed at low temperatures. Therefore, there is an advantage that the heat energy required for the press working is low and the manufacturing cost can be reduced. The same applies hereinafter.

  Moreover, the 2nd manufacturing method of the metal clad laminated board which concerns on this invention passes through the following process A-2-the process C-2, It is characterized by the above-mentioned.

Step A-2: In this step, the activation surface is applied to the bonding surface of the metal foil of the fluororesin substrate, which is the same as in the case of the first manufacturing method. Therefore, the description is omitted. FIG. 6A conceptually shows the activated fluororesin substrate 5.

Step B-2: In this step, the fluororesin substrate adhesive is prepared by the above-described method, and this fluororesin substrate adhesive is applied to the surface of the releasable plastic film 7 and dried. As shown in FIG. 6 (b), the release plastic film and a semi-cured resin layer having a thickness of 0.5 μm to 3 μm (in the drawing, simply indicated as “adhesive layer 3”) are in a laminated state. The adhesive layer with moldable plastic film 8 is manufactured.

  Here, the releasable plastic film is used in the sense of selectively using a film having releasability, and there is no particular limitation on the material, thickness, and the like. Specifically, it is preferable to use a PET film, a thermoplastic fluororesin film, a polyimide resin film, or the like. The method for applying the adhesive for the fluororesin substrate to the releasable plastic film at this time is not particularly limited, and an edge coater, comma coater, gravure coater, or the like can be used.

Step C-2: In this step, as shown in FIG. 6C, the semi-cured resin layer of the adhesive layer 8 with the releasable plastic film (on the bonded surface subjected to the activation treatment of the fluororesin substrate 5 ( In the drawing, it is simply shown as “adhesive layer 3”), and they are brought into contact with each other to be temporarily bonded, and the releasable plastic film 7 is peeled and removed.

Step D-2: In this step, hot pressing is performed by laminating the metal foil 2 on the surface of the semi-cured resin layer provided on the surface of the fluororesin substrate in Step C-2 as shown in FIG. By doing so, the metal-clad laminate 1a shown in FIG.

  And the 3rd manufacturing method of the metal-clad laminated board which concerns on this invention passes through the following process A-3-process C-3, It is characterized by the above-mentioned.

Step A-3: In this step, activation treatment is performed on the bonding surface of the metal foil of the fluororesin base material, which is the same as in the case of the first manufacturing method. Therefore, the description is omitted. FIG. 7A conceptually shows the activated fluororesin base material 5.

Step B-3: In this step, an adhesive for a fluororesin substrate is prepared. Therefore, since the description regarding this adjustment is as above-mentioned, the overlapping description here is abbreviate | omitted.

Step C-3: In this step, the surface of the fluororesin substrate 5 subjected to the activation treatment is coated with the adhesive for fluororesin substrate prepared in Step B and dried, as shown in FIG. 7B. In this manner, a semi-cured resin layer (indicated as simply “adhesive layer 3” in the drawing) having a thickness of 0.5 μm to 3 μm is formed. The method for applying the adhesive for the fluororesin substrate at this time is not particularly limited, and an edge coater, a comma coater, a gravure coater, or the like can be used.

Step D-3: In this step, the metal foil 2 is applied to the surface of the semi-cured resin layer (shown as “adhesive layer 3” in the drawing) provided on the surface of the fluororesin substrate 5 in Step C-3. By laminating and hot press forming, a metal-clad laminate 1a shown in FIG.

  In the above description of the method for manufacturing a metal-clad laminate, only a single-sided metal-clad laminate has been described as an example. However, those skilled in the art can easily perform a double-sided copper-clad laminate on the basis of the same technical idea. It is possible to produce a multilayer copper-clad laminate.

  In this example, a copper clad laminate was produced using the first production method, and the peel strength of the copper foil was measured. Hereinafter, it demonstrates for every process.

Step A-1: In this step, an activation treatment was performed on the bonding surface of the metal foil of the PTFE fluororesin base material (manufactured by Yodogawa Hutec Co., Ltd.) having a thickness of 0.6 mm. This activation treatment includes three types of metal treatment, plasma treatment, and composite treatment in which metal sodium treatment and plasma treatment are sequentially performed. Three types of fluororesin base materials, Sample 1, Sample 2, and Sample 3 were manufactured.

  Metal sodium treatment at this time is the activity of the surface of the fluororesin substrate by drawing out fluorine atoms from the surface of the fluororesin substrate by the action of metal sodium or sodium complex, and generating hydroxyl, carbonyl or carboxyl groups on the surface. Here, a tetra-etch treatment solution manufactured by Junkosha Co., Ltd. was used.

In the plasma treatment, a pair of plate-like electrodes are disposed in parallel in the vacuum chamber, the vacuum degree is evacuated to the order of 1 × 10 ⁻³ Pa, nitrogen gas is slowly leaked into the vacuum chamber, and the vacuum treatment is performed. The temperature was adjusted to 0.2 Pa, and a low-temperature plasma stream was generated at a power density of 0.12 W / cm ² . And the plasma processing was performed by putting a fluororesin base material into this low-temperature plasma stream for 1 minute.

  Further, in the combined treatment in which the metal sodium treatment and the plasma treatment were sequentially performed, the metal sodium treatment and the plasma treatment under the above conditions were sequentially performed.

  The activation treatment described above was performed to obtain an activated fluorine resin base material 5 schematically shown in FIG.

Step B-1: Here, fluorine resin of 69 parts by weight of epoxy resin, 11 parts by weight of curing agent, 0.25 part by weight of curing accelerator, 15 parts by weight of polymer component, 3 parts by weight of crosslinking agent, and 3 parts by weight of rubber resin A resin composition for substrate adhesion was prepared. Specifically, it is shown in Table 1 below.

  And the resin composition shown in Table 1 was made into the adhesive for fluororesin base materials by adjusting resin solid content to 30 weight% using methyl ethyl ketone and dimethylacetamide. And this adhesive agent for fluororesin base materials is a roughened electrolytic copper foil (thickness: 18 μm, rust prevention treatment layer: zinc-nickel alloy layer, silane coupling agent treatment: γ-) using a gravure coater. Aminopropyltriethoxysilane) was applied to the bonding surface. Then, it is air-dried for 5 minutes, and then subjected to a drying process for 3 minutes in a heated atmosphere at 140 ° C. to form a semi-cured 1.5 μm-thick semi-cured resin layer (adhesive layer). The metal foil 4 with an adhesive layer shown in b) was produced.

  The resin flow of the semi-cured resin layer (adhesive layer) obtained at this time was measured by providing a 40 μm-thick semi-cured resin layer on one side of an 18 μm-thick copper foil with the above-mentioned adhesive for fluororesin substrate. A product was manufactured and used as a resin flow measurement sample. And four 10 cm square samples were extract | collected from this resin flow measurement sample, and the resin flow was measured based on MIL-P-13949G mentioned above. As a result, the resin flow was 1.5%.

Step C-1: In this step, as shown in FIG. 5C, the activation treatment of the fluororesin base material of the three samples (sample 1, sample 2, sample 3) obtained in step A-1 is performed. The adhesive layer 3 of the metal foil 4 with an adhesive layer obtained in Step B-1 is laminated on the laminated surface thus applied, and hot press-molded at 200 ° C. for 60 minutes at a pressure of 32 kgf / cm ^2. As a result, three types (CL1-1, CL1-2, CL1-3) of the metal-clad laminate 1a shown in FIG. 5D were obtained.

Manufacture of peel strength measurement sample: An etching resist layer is formed on a copper foil layer of the metal-clad laminate 1a (CL1-1, CL1-2, CL1-3) using a dry film, and this etching resist layer By exposing and developing the etching pattern for forming a linear circuit for measuring the peel strength, forming a resist pattern, etching the circuit with the copper etching solution with the metal component of the metal foil, and peeling the resist Then, a circuit for measuring the peel strength was formed. A 0.2 mm wide linear circuit is used for measuring normal and hydrochloric acid resistance, and a 0.8 mm wide linear circuit is used for measuring moisture resistance.

  And the peeling strength measurement of a fluororesin base material and a copper foil circuit was performed. The results are shown in Table 2. The peel strength referred to in this specification is the strength when the copper foil circuit is peeled from the base material in the 90 ° direction (perpendicular to the substrate). Among them, the normal peel strength is the peel strength measured without performing any treatment immediately after the circuit is manufactured by etching as described above. The peeling strength after heating is the peeling strength measured after floating in a solder bath at 260 ° C. for 20 seconds and then cooled to room temperature.

  The hydrochloric acid resistance deterioration rate was determined by preparing a test circuit and measuring the normal peel strength immediately after the hydrochloric acid treatment described in each table (hydrochloric acid: water = 1: 1 after immersion for 60 minutes at room temperature). ) Shows how much the peel strength is deteriorated, [Hydrochloric acid resistance deterioration rate (%)] = ([Normal peel strength] − [Peel strength after hydrochloric acid treatment] ) / [Normal peel strength] × 100.

  In addition, the moisture resistance deterioration rate is determined from the normal peel strength measured immediately after creating a test circuit, after the moisture absorption treatment described in each table (after holding in boiling ion exchange water for 2 hours). This indicates whether or not the peel strength has deteriorated. [Deterioration rate of moisture resistance (%)] = ([Normal peel strength]-[Peel strength after moisture absorption]) / [Normal pull Peeling strength] × 100. Therefore, the smaller the deterioration rate, the better the adhesion between the fluororesin substrate and the copper foil circuit.

  In this example, a copper clad laminate was produced using the second production method, and the peel strength of the copper foil was measured. Hereinafter, it demonstrates for every process.

Step A-2: Since this step is the same as that of the first embodiment, a description thereof will be omitted. Therefore, three types of fluororesin base materials, Sample 1, Sample 2, and Sample 3 were also produced here. FIG. 6A conceptually shows the activated fluororesin substrate 5.

Step B-2: This step uses the same adhesive for a fluororesin substrate as prepared in Example 1, and uses this adhesive for a fluororesin substrate as a releasable plastic film 7 using a PET film. Then, the surface is coated with a gravure coater, air-dried for 5 minutes, and then dried in a heated atmosphere at 140 ° C. for 3 minutes, as shown in FIG. An adhesive layer 8 with a releasable plastic film in which a plastic film and a 1.5 μm semi-cured resin layer (indicated as simply “adhesive layer 3” in the drawing) are in a laminated state was produced.

Step C-2: In this step, as shown in FIG. 6C, the semi-cured resin layer of the adhesive layer 8 with the releasable plastic film (on the bonded surface subjected to the activation treatment of the fluororesin substrate 5 ( In the drawing, it is simply shown as “adhesive layer 3”), and they are brought into contact with each other and are temporarily bonded by gentle pressure, and the releasable plastic film 7 is peeled and removed.

Step D-2: In this step, the same non-roughened copper foil (metal foil) 2 used in Example 1 is applied to the surface of the semi-cured resin layer provided on the surface of the fluororesin substrate in Step C-2. 6 (d) are laminated, and are subjected to hot press molding at a pressure of 32 kgf / cm ² at 200 ° C. for 60 minutes, so that three kinds of layers (CL2− 1, CL2-2, CL2-3) metal-clad laminate 1a.

  Hereinafter, the sample for peeling strength measurement was manufactured like Example 1, and the peeling strength measurement of a fluororesin base material and a copper foil circuit was performed. The results are shown in Table 3.

  In this example, a copper clad laminate was produced using the third production method, and the peel strength of the copper foil was measured. Hereinafter, it demonstrates for every process.

Process A-3: Since this process is the same as that of Example 1, it abbreviate | omits. Therefore, three types of fluororesin base materials, Sample 1, Sample 2, and Sample 3 were also produced here. FIG. 7A conceptually shows the activated fluororesin base material 5.

Step B-3: In this step, the same adhesive for a fluororesin substrate as that prepared in Example 1 was prepared.

Step C-3: In this step, the fluororesin substrate adhesive prepared in Step B-3 is applied to the activated surface of the fluororesin substrate 5 and air-dried for 5 minutes, and then 140 ° C. By drying in a heated atmosphere for 3 minutes, a semi-cured resin layer having a thickness of 1.5 μm (shown as “adhesive layer 3” in the drawing) as shown in FIG. Formed. Application of the adhesive for a fluororesin substrate at this time was performed using an edge coater.

Step D-3: Here, on the surface of the semi-cured resin layer (in the drawing, simply indicated as “adhesive layer 3”) provided on the surface of the fluororesin substrate 5 in Step C-3, a thickness of 18 μm is provided. By laminating the same copper foil (metal foil) 2 as used in Example 1 and hot pressing at a pressure of 32 kgf / cm ² at 200 ° C. for 60 minutes, the layer structure shown in FIG. Three types (CL3-1, CL3-2, CL3-3) of the metal-clad laminate 1a were used.

  Hereinafter, the sample for peeling strength measurement was manufactured like Example 1, and the peeling strength measurement of a fluororesin base material and a copper foil circuit was performed. This result is shown in Table 4.

  As seen from the examples described above, in all embodiments, a non-roughened metal foil is used, but the normal peel strength and the peel strength after heating are all 1.0 kgf / cm. Over. This can be said to be drastically increased considering that the peel strength between the conventional fluororesin substrate and the metal foil is around 0.8 kgf / cm.

  In all the embodiments, the hydrochloric acid resistance deterioration rate is within 5%, and the moisture resistance deterioration rate is within 10%. In the case of conventional fluororesin printed wiring boards, considering that the hydrochloric acid resistance deterioration rate is around 10% and the moisture resistance deterioration rate is 15% or more, even when using a non-roughened metal foil, It can be said that the adhesion between the fluororesin substrate and the metal foil is improved.

  With the contents according to the present invention as described above, the non-roughened metal foil and the fluororesin base material exhibit extremely high adhesion, and effectively prevent the delamination phenomenon of the circuit when subjected to a heat shock. It is possible to provide a fluororesin copper-clad laminate and a fluororesin printed wiring board. In addition, since a non-roughened metal foil can be used, the fine pitch pattern can be easily formed even when the circuit is formed by an etching method. Therefore, it has good dielectric properties such as low dielectric loss and low dielectric constant, good high-frequency characteristics related to crosstalk characteristics, etc., other heat resistance and durability, excellent adhesion between circuit and substrate, and fine pitch pattern A high-quality fluororesin printed wiring board equipped with can be supplied to the market at a low cost. In addition, the method for manufacturing a metal-clad laminate according to the present invention does not require a new apparatus, can use conventional equipment, and can be pressed at a low temperature, so that the manufacturing cost is low. It is.

It is a schematic cross section which shows the layer structure of the metal foil with an adhesive layer which concerns on this invention. It is a schematic cross section which shows an example of the variation of the layer structure of the metal-clad laminated board which concerns on this invention. It is a schematic diagram which shows the image of multilayer printed wiring board manufacture. It is a schematic diagram which shows the image of multilayer printed wiring board manufacture. It is a flowchart for demonstrating the manufacturing process of the metal-clad laminated board which concerns on this invention. It is a flowchart for demonstrating the manufacturing process of the metal-clad laminated board which concerns on this invention. It is a flowchart for demonstrating the manufacturing process of the metal-clad laminated board which concerns on this invention.

Explanation of symbols

1a, 1b, 1c Metal-clad laminate 2 Metal foil 3 Adhesive layer 4 Metal foil with adhesive layer 5 Fluororesin substrate layer 7 Releasable plastic film 8 Adhesive layer with releasable plastic film 9 Inner layer circuit 20 Circuit 21 Double-sided printing Wiring board 22 prepreg

Claims (17)

In the resin composition for forming an adhesive layer for bonding the metal foil to the fluororesin substrate,
The resin composition is 2 to 50 parts by weight of a polymer component that is soluble in a solvent and has one or more of hydroxyl group, carboxyl group, and amino group in the molecule as a functional group,
50 parts by weight or more of an epoxy resin compound comprising an epoxy resin having a boiling point of 200 ° C. or higher and an amine epoxy resin curing agent having a boiling point of 200 ° C. or higher,
A resin composition for adhering a fluororesin base material, comprising: The said polymer component is what mixed 1 type, or 2 or more types chosen from the group of polyvinyl acetal resin, phenoxy resin, aromatic polyamide resin, polyether sulfone resin, and polyamide-imide resin. Resin composition for fluororesin substrate adhesion. The epoxy resin having a boiling point of 200 ° C. or higher is a mixture of one or more selected from the group of bisphenol A type epoxy resin, bisphenol F type epoxy resin, rubber-modified bisphenol A type epoxy resin, and biphenyl type epoxy resin. A resin composition for adhering a fluororesin substrate according to claim 1 or 2. The amine-based epoxy resin curing agent is an aromatic polyamine, polyamides, and one or more selected from the group of amine adducts obtained by polymerizing or condensing these with an epoxy resin or a polyvalent carboxylic acid. Item 4. The resin composition for bonding a fluororesin substrate according to any one of Items 1 to 3. A resin adhesive used for laminating a metal foil to a fluororesin substrate,
An adhesive for a fluororesin substrate obtained by adding an organic solvent to the resin composition for a fluororesin substrate according to any one of claims 1 to 4 and mixing them. 6. The adhesive for a fluororesin substrate according to claim 5, wherein the organic solvent is any one of methyl ethyl ketone, cyclopentanone, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, or a mixed solvent thereof. In the metal foil with an adhesive layer provided with an adhesive layer for the substrate on the surface of the metal foil,
The said adhesive layer is formed using the resin adhesive for fluororesin substrates of the said Claim 5 or Claim 6, The metal foil with the adhesive layer for fluororesin base materials characterized by the above-mentioned. The metal foil with an adhesive layer for a fluororesin substrate according to claim 7, wherein the adhesive layer of the metal foil with an adhesive layer is a semi-cured resin layer having a thickness of 0.5 μm to 3 μm. The adhesive layer of the metal foil with an adhesive layer has a characteristic that the resin flow is within 5% when measured according to MIL-P-13949G in the MIL standard. Metal foil with adhesive layer for fluororesin substrate. The metal foil is copper foil, nickel foil, tin foil, gold foil, silver foil, platinum foil, iron foil, cobalt foil, copper alloy foil, nickel alloy foil, tin alloy foil, gold alloy foil, silver alloy foil, platinum alloy foil The metal foil with an adhesive layer for a fluororesin substrate according to any one of claims 7 to 9, wherein any one of iron alloy foil and cobalt alloy foil is used. A metal-clad laminate obtained by laminating a metal layer on the surface of a fluororesin substrate via an adhesive layer,
The said adhesion layer contains the resin composition in any one of Claims 1-4, The metal-clad laminated board characterized by the above-mentioned. A metal-clad laminate obtained by laminating a metal layer on the surface of a fluororesin substrate via an adhesive layer,
The metal-clad laminate, wherein the adhesive layer is formed using the fluororesin substrate adhesive according to claim 5. A printed wiring board obtained by etching a metal foil of the metal-clad laminate according to claim 11 or 12. It is a manufacturing method of the metal-clad laminated board of Claim 11 or Claim 12, Comprising: It passes through the following process A-1-process C-1, The manufacturing method of the metal-clad laminated board characterized by the above-mentioned.
Step A-1: A step of applying an activation treatment to the bonding surface of the fluororesin substrate with the metal foil.
Step B-1: A fluororesin substrate adhesive is prepared, and this fluororesin substrate adhesive is applied to the surface of the metal foil and dried, so that the thickness of the metal foil is 0.5 μm to 3 μm. The process of manufacturing metal foil with an adhesive layer by forming a semi-cured resin layer.
Step C-1: A metal-clad laminate is obtained by hot-pressing the adhesive layer surface of the metal foil with an adhesive layer in contact with the laminated surface subjected to the activation treatment of the fluororesin substrate and laminating it. Process. It is a manufacturing method of the metal-clad laminated board of Claim 11 or Claim 12, Comprising: The manufacturing method of the metal-clad laminated board which passes through following process A-2-process C-2.
Step A-2: A step of performing an activation treatment on the bonding surface of the fluororesin base material with the metal foil.
Step B-2: An adhesive for a fluororesin substrate is prepared, and the adhesive for a fluororesin substrate is applied to the surface of the releasable plastic film and dried, so that the releasable plastic film and thickness A step of producing an adhesive layer with a releasable plastic film in which a semi-cured resin layer of 0.5 μm to 3 μm is in a laminated state.
Step C-2: The semi-cured resin layer of the adhesive layer with a releasable plastic film is brought into contact with the laminated surface subjected to the activation treatment of the fluororesin base material, and is temporarily bonded to each other. The process of peeling off and leaving the semi-cured resin layer on the surface of the fluororesin substrate.
Step D-2: A step of forming a metal-clad laminate by laminating a metal foil on the surface of the semi-cured resin layer provided on the surface of the fluororesin substrate in Step C-2 and hot pressing it. It is a manufacturing method of the metal-clad laminated board of Claim 11 or Claim 12, Comprising: It passes through the following process A-3-process D-3, The manufacturing method of the metal-clad laminated board characterized by the above-mentioned.
Step A-3: A step of performing activation treatment on the bonding surface of the metal foil of the fluororesin base material.
Process B-3: The process of preparing the adhesive for fluororesin base materials.
Step C-3: Applying the adhesive for the fluororesin substrate prepared in Step B-3 to the activated surface of the fluororesin substrate and drying it, semi-curing 0.5 μm to 3 μm in thickness Forming a resin layer;
Step D-3: Step of forming a metal-clad laminate by laminating a metal foil on the surface of the semi-cured resin layer provided on the surface of the fluororesin substrate in Step C-3 and hot pressing it. The method for producing a metal-clad laminate according to any one of claims 14 and 15, wherein the activation treatment is any one of a roughening treatment, a plasma treatment, or a composite treatment combining these.

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