JP6170211B1 - Thermosetting adhesive composition, coverlay film, adhesive film, metal-clad laminate and flexible printed wiring board - Google Patents

Abstract

[PROBLEMS] To have excellent storage stability and embedding property, capable of sufficiently suppressing leaching during curing by thermocompression bonding, and excellent adhesion to any of polyimide resin, copper and aluminum after curing. A thermosetting adhesive composition, a cover lay film, an adhesive film, a metal-clad laminate, and a flexible printed wiring board capable of having excellent solder heat resistance while having properties. An acrylic resin (B) is blended in an amount of 1 to 50 parts by mass with respect to 100 parts by mass of a polyester urethane resin (A), and an epoxy resin (C) is 5 to 50 parts by mass. Polyester urethane resin (A1) having a glass transition temperature of 30 ° C. or more and 100 ° C. or less and a hydroxyl value of 3 KOH mg / g or more and 18 KOH mg / g or less, Containing polyester urethane resin (A2) having a glass transition temperature of 25 ° C. or higher and lower than 30 ° C., and containing 100% by mass of polyester urethane resin (A1) in total of polyester urethane resin (A1) and polyester urethane resin (A2) The rate is 50% by mass or more and 95% by mass or less, and the acrylic resin (B) is −70 ° C. or more and 50 ° C. or less. Thermosetting adhesive composition having a glass transition temperature of. [Selection figure] None

Description

  The present invention relates to a thermosetting adhesive composition, a coverlay film, an adhesive film, a metal-clad laminate, and a flexible printed wiring board.

  Thermosetting adhesive compositions are widely used as adhesives that are cured by heating and adhere members that constitute wiring boards such as flexible printed wiring boards and contact IC cards.

  As such a thermosetting adhesive composition, for example, a heat-and-moisture resistant hot melt adhesive composition described in Patent Document 1 below is known. Patent Document 1 below discloses a wet heat resistant hot melt adhesive composition in which a polyurethane resin, an epoxy resin, a polyester resin, and an inorganic filler surface-treated with a coupling agent are blended.

JP 2003-27030 A

  By the way, in general, thermosetting adhesive compositions used for wiring boards such as flexible printed wiring boards generally have storage stability, embedding ability in gaps between circuits, and suppression of leaching when cured by thermocompression bonding. It is required to have excellent adhesion to cured resin and metal, and solder heat resistance after curing.

  However, the wet heat resistant hot melt adhesive described in Patent Document 1 has the following problems. That is, although the heat-and-moisture resistant hot melt adhesive described in Patent Document 1 is excellent in adhesiveness with copper constituting the circuit, it may be inferior in adhesiveness with the polyimide resin or aluminum constituting the substrate. When used as an adhesive layer between substrates constituting a wiring board such as a flexible printed wiring board by curing, peeling may occur between the substrate and the adhesive layer during use of the flexible printed wiring board. For this reason, when peeling arises between a board | substrate and an adhesive layer, it was necessary to use another kind of adhesive composition excellent in the adhesiveness with a board | substrate. That is, the heat-and-moisture resistant hot melt adhesive described in Patent Document 1 has room for improvement in terms of versatility.

  The present invention has been made in view of the above circumstances, has excellent storage stability and embedding property, and can sufficiently suppress leaching upon curing by thermocompression bonding, and after curing, a polyimide resin, Thermosetting adhesive composition, cover lay film, adhesive film, metal-clad laminate, and flexible, capable of having excellent solder heat resistance while having excellent adhesion to both copper and aluminum An object is to provide a printed wiring board.

  As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by the following invention.

  That is, in the present invention, the acrylic resin (B) is blended at a ratio of 1 to 50 parts by mass with respect to 100 parts by mass of the polyester urethane resin (A), and the epoxy resin (C) is 5 to 50 parts by mass. Polyester urethane resin (A1) blended in the following proportion, the polyester urethane resin (A) having a glass transition temperature of 30 ° C. or higher and 100 ° C. or lower and having a hydroxyl value of 3 KOH mg / g or higher and 18 KOH mg / g or lower; Polyester urethane resin (A2) having a glass transition temperature of −25 ° C. or more and less than 30 ° C., and the polyester urethane resin in a total of 100 mass% of the polyester urethane resin (A1) and the polyester urethane resin (A2). The content of (A1) is 50% by mass or more and 95% by mass or less, and the acrylic resin (B) A thermosetting adhesive composition having a glass transition temperature of -70 ° C. or higher 50 ° C. or less.

  According to this thermosetting adhesive composition, it is possible to have excellent adhesion to any of polyimide resin, copper and aluminum after curing. That is, the thermosetting adhesive composition of the present invention can have versatility as an adhesive used for manufacturing a wiring board such as a flexible printed wiring board (hereinafter referred to as “FPC”). Further, according to the thermosetting adhesive composition of the present invention, it has excellent storage stability and embedding property, can sufficiently suppress leaching during curing by thermocompression bonding, and is excellent in solder after curing. It is also possible to have heat resistance.

  Moreover, this invention is a coverlay film provided with an insulating film and the adhesive bond layer provided on the said insulating film, and the said adhesive bond layer is obtained using the said thermosetting adhesive composition.

  According to this coverlay film, the adhesive layer is obtained by using a thermosetting adhesive composition having excellent adhesion to any of polyimide resin, copper and aluminum after curing. For this reason, when an FPC is manufactured using the cover lay film of the present invention, if the insulating film is composed of a polyimide film, peeling between the insulating film and the adhesive layer obtained by curing the adhesive layer Can be sufficiently suppressed. Moreover, according to the coverlay film of this invention, when the contact bonding layer is adhere | attached on the metal layer which consists of copper, peeling between a metal layer and an contact bonding layer can also be fully suppressed. Furthermore, the said thermosetting adhesive composition also has the outstanding embedding property. For this reason, when manufacturing the FPC by bonding the metal-clad laminate to the cover lay film of the present invention, an adhesive layer obtained using the thermosetting adhesive composition has a circuit formed on the metal layer, etc. It is possible to be fully embedded in the gap. For this reason, since the contact area of a metal layer and an adhesive bond layer can be enlarged, after hardening an adhesive bond layer to make it an adhesive layer, peeling between an adhesive layer and a metal layer is fully suppressed. be able to. Further, the thermosetting adhesive composition has excellent solder heat resistance after curing. For this reason, when soldering an electronic component etc. with respect to FPC manufactured using the coverlay film of this invention, it can fully suppress that peeling arises in FPC when a swelling occurs in an adhesion layer. . Furthermore, the thermosetting adhesive composition can sufficiently suppress leaching during curing by thermocompression bonding. For this reason, when manufacturing the FPC by bonding the cover lay film of the present invention to a metal-clad laminate by thermocompression bonding, the leaching of the adhesive layer contained in the cover lay film of the present invention can be sufficiently suppressed.

  Moreover, this invention is an adhesive film containing the adhesive bond layer obtained using the said thermosetting adhesive composition.

  According to this adhesive film, the adhesive layer is obtained using a thermosetting adhesive composition having excellent adhesiveness to any of polyimide resin, copper and aluminum after curing. For this reason, when manufacturing FPC using the adhesive film of this invention, when the board | substrate which contacts the contact bonding layer obtained by hardening | curing an adhesive bond layer is comprised with a polyimide film or an aluminum plate, the polyimide film Alternatively, peeling between the aluminum plate and the adhesive layer can be sufficiently suppressed. The thermosetting adhesive composition has excellent solder heat resistance after curing. For this reason, when manufacturing an FPC using the adhesive film of the present invention, when mounting electronic components on the FPC, it is sufficiently suppressed that the adhesive layer is swelled to cause peeling in the FPC. can do. Furthermore, the thermosetting adhesive composition can sufficiently suppress leaching during curing by thermocompression bonding. For this reason, when manufacturing FPC by thermocompression bonding using the adhesive film of the present invention, leaching of the adhesive layer can be sufficiently suppressed.

  The present invention also includes a base film, a metal layer provided on one surface side of the base film, and an adhesive layer provided between the base film and the metal layer, wherein the adhesive layer is the thermoset. It is a metal-clad laminate obtained by using the adhesive composition.

  According to this metal-clad laminate, an adhesive layer is obtained using a thermosetting adhesive composition having excellent solder heat resistance after curing. For this reason, when soldering an electronic component or the like to an FPC manufactured using the metal-clad laminate of the present invention, the adhesive layer obtained by curing the adhesive layer causes swelling to occur in the base film and It is possible to sufficiently suppress the occurrence of peeling between the adhesive layer. Moreover, the said thermosetting adhesive composition has the adhesiveness outstanding with respect to all of polyimide resin, copper, and aluminum after hardening. For this reason, when FPC is manufactured using the metal-clad laminate of the present invention and the adhesive layer is made into an adhesive layer by curing, if the base film of the metal-clad laminate is composed of a polyimide film, it adheres to the base film. Separation between the layers can be sufficiently suppressed. Further, when the metal layer contains copper, peeling between the adhesive layer and the metal layer can be sufficiently suppressed in the FPC. Moreover, the said thermosetting adhesive composition can fully suppress leaching at the time of hardening by thermocompression bonding. For this reason, when manufacturing the FPC by bonding the metal-clad laminate of the present invention and the coverlay film, it is possible to sufficiently suppress the leaching of the adhesive layer.

  The present invention also provides a metal-clad laminate having a metal layer on one side of a base film, the coverlay film, the adhesive layer of the coverlay film, and the metal layer of the metal-clad laminate. Is an FPC that is thermocompression-bonded with the two facing each other.

  This FPC is formed by thermocompression bonding a metal-clad laminate and a coverlay film with the adhesive layer of the coverlay film and the metal layer of the metal-clad laminate facing each other. For this reason, in the FPC of the present invention, the adhesive layer of the coverlay film is cured to form an adhesive layer. At this time, the adhesive layer is obtained using a thermosetting adhesive composition having excellent solder heat resistance after curing. For this reason, when soldering an electronic component etc. with respect to FPC of this invention, it can fully suppress that peeling arises between an insulating film or a base film, and an adhesive layer when a swelling occurs in an adhesive layer. it can. Further, since the adhesive layer is obtained by curing the adhesive layer, it has excellent adhesion to polyimide resin, copper and aluminum. For this reason, FPC of this invention can fully suppress that peeling arises between the polyimide film and an adhesive layer, when an insulating film and / or a base film are comprised with a polyimide film. Further, in the FPC, when the metal layer contains copper, peeling between the adhesive layer and the metal layer can be sufficiently suppressed.

  Further, the present invention provides a reinforcing material, a metal-clad laminate in which a metal layer is provided on one surface side of the base film, the coverlay film, the adhesive layer of the coverlay film, and the metal-clad laminate. The thermosetting adhesive is formed by thermocompression bonding in a state where the metal layer is opposed and an adhesive film is interposed between the reinforcing material and the metal-clad laminate. It is FPC obtained using a composition.

  This FPC has a reinforcing material, a metal-clad laminate, a coverlay film, an adhesive layer of the coverlay film, and a metal layer of the metal-clad laminate, and a reinforcing material and a metal-clad laminate. It is thermocompression bonded with an adhesive film interposed between the plates. As a result, in the FPC of the present invention, the adhesive layer and the adhesive film of the coverlay film are cured to form an adhesive layer. At this time, the adhesive layer is obtained using a thermosetting adhesive composition having excellent solder heat resistance after curing. For this reason, when soldering an electronic component etc. to the FPC of the present invention, it is possible to sufficiently suppress the occurrence of peeling between the insulating film, the base film and the reinforcing material and the adhesive layer due to the swelling of the adhesive layer. can do. Moreover, since an adhesive layer is obtained by hardening | curing the said adhesive bond layer, it has the adhesiveness outstanding with respect to all of a polyimide resin, copper, and aluminum. For this reason, FPC of this invention can fully suppress peeling between the polyimide film and an adhesive layer, when an insulating film and / or a base film are comprised with a polyimide film. Furthermore, when the metal layer contains copper in the FPC, peeling between the adhesive layer and the metal layer can be sufficiently suppressed. Furthermore, when the reinforcing material is composed of a polyimide film or an aluminum plate, peeling between the reinforcing material and the adhesive layer can be sufficiently suppressed.

  In the FPC, it is preferable that the metal-clad laminate includes an adhesive layer between the base film and the metal layer, and the adhesive layer is obtained using the thermosetting adhesive composition.

  In this case, the adhesive strength between the base film and the metal layer can be further improved.

  According to the present invention, it has excellent storage stability and embedding property, and can sufficiently suppress leaching during curing by thermocompression bonding, and can be applied to any of polyimide resin, copper and aluminum after curing. There are provided a thermosetting adhesive composition, a coverlay film, an adhesive film, a metal-clad laminate, and an FPC capable of having excellent solder heat resistance while having excellent adhesiveness.

It is sectional drawing which shows one Embodiment of the coverlay film which concerns on this invention. It is sectional drawing which shows one Embodiment of the adhesive film which concerns on this invention. It is sectional drawing which shows one Embodiment of the metal-clad laminated board which concerns on this invention. It is sectional drawing which shows one Embodiment of FPC which concerns on this invention. It is sectional drawing which shows the process of manufacturing FPC of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as necessary. In all the drawings, the same or identical components are denoted by the same reference numerals, and redundant description is omitted.

<Thermosetting adhesive composition>
First, the thermosetting adhesive composition of the present invention will be described.

  In the thermosetting adhesive composition of the present invention, the acrylic resin (B) is blended at a ratio of 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the polyester urethane resin (A), and the epoxy resin (C) It is blended at a ratio of 5 parts by mass or more and 50 parts by mass or less. The polyester urethane resin (A) has a glass transition temperature of 30 ° C. or more and 100 ° C. or less, and a polyester urethane resin (A1) having a hydroxyl value of 3 KOH mg / g or more and 18 KOH mg / g or less, and −25 ° C. or more and 30 ° C. The polyester urethane resin (A2) having a glass transition temperature of less than 50% by weight of the polyester urethane resin (A1) in a total of 100% by mass of the polyester urethane resin (A1) and the polyester urethane resin (A2). The acrylic resin (B) has a glass transition temperature of −70 ° C. or higher and 50 ° C. or lower.

  According to this thermosetting adhesive composition, it is possible to have excellent adhesion to any of polyimide resin, copper and aluminum after curing. That is, the thermosetting adhesive composition of the present invention can have versatility as an adhesive used for manufacturing a wiring board such as an FPC. Further, according to the thermosetting adhesive composition of the present invention, it has excellent storage stability and embedding property, can sufficiently suppress leaching during thermosetting by thermocompression bonding, and has excellent solder after curing. It becomes possible to have heat resistance.

  Next, the polyester urethane resin (A), the acrylic resin (B), and the epoxy resin (C) will be described in more detail.

(A) Polyester urethane resin A polyester urethane resin (A) consists of a polyester urethane resin (A1) and a polyester urethane resin (A2).

  As the polyester urethane resin (A1), a thermosetting resin capable of reacting with the epoxy resin (C) is used.

  The polyester urethane resin (A1) has a glass transition temperature of 30 ° C. or higher and 100 ° C. or lower and a hydroxyl value of 3 KOH mg / g or higher and 18 KOH mg / g or lower. When the glass transition temperature of the polyester urethane resin (A1) is lower than 30 ° C., the solder heat resistance of a cured product (hereinafter simply referred to as “cured product”) obtained by thermosetting the thermosetting adhesive composition is lowered. . On the other hand, when the glass transition temperature of the polyester urethane resin (A1) is higher than 100 ° C., the embedding property of the thermosetting adhesive composition is lowered. Moreover, when the hydroxyl value of the polyester urethane resin (A1) is less than 3 KOH mg / g, the adhesiveness between the cured product and aluminum is lowered. On the other hand, when the hydroxyl value of the polyester urethane resin (A1) is larger than 18 KOHmg / g, the storage stability of the thermosetting adhesive composition is lowered.

  The glass transition temperature of the polyester urethane resin (A1) is preferably 34 ° C. or higher and 73 ° C. or lower.

  The hydroxyl value of the polyester urethane resin (A1) is preferably 5 KOHmg / g or more and 10 KOHmg / g or less.

  As the polyester urethane resin (A2), a thermosetting resin capable of reacting with the epoxy resin (C) is used.

  The polyester urethane resin (A2) has a glass transition temperature of −25 ° C. or higher and lower than 30 ° C. When the glass transition temperature of the polyester urethane resin (A2) is lower than −25 ° C., leaching of the thermosetting adhesive composition at the time of curing by thermocompression bonding cannot be sufficiently suppressed. On the other hand, when the glass transition temperature of the polyester urethane resin (A2) is 30 ° C. or higher, the embedding property of the thermosetting adhesive composition is lowered.

  The glass transition temperature of the polyester urethane resin (A2) is preferably −22 ° C. or higher and 25 ° C. or lower, and more preferably 0 ° C. or higher and 25 ° C. or lower.

  The hydroxyl value of the polyester urethane resin (A2) is not particularly limited, but is preferably 5 KOHmg / g or more and 10 KOHmg / g or less.

  The content of the polyester urethane resin (A1) in the total 100% by mass of the polyester urethane resin (A1) and the polyester urethane resin (A2) is 50% by mass or more and 95% by mass or less. When the content of the polyester urethane resin (A1) in 100% by mass of the polyester urethane resin (A) is higher than 95% by mass, the adhesiveness between the cured product and the polyimide resin is lowered. On the other hand, when the content of the polyester urethane resin (A1) is less than 50% by mass, the adhesiveness between the cured product and aluminum is lowered.

  The content of the polyester urethane resin (A1) in the total 100% by mass of the polyester urethane resin (A1) and the polyester urethane resin (A2) is more preferably 70% by mass to 90% by mass.

(B) Acrylic resin The acrylic resin (B) has a glass transition temperature of −70 ° C. or higher and 50 ° C. or lower. In this case, compared with the case where the glass transition temperature of acrylic resin (B) is less than -70 degreeC, the leaching at the time of hardening by thermocompression bonding can fully be suppressed. Moreover, compared with the case where the glass transition temperature of an acrylic resin (B) exceeds 50 degreeC, the thermosetting adhesive composition has the embedding property which was excellent. The glass transition temperature of the acrylic resin (B) is preferably −40 ° C. or higher and 30 ° C. or lower. In this case, the amount of dyeing of the thermosetting adhesive composition at the time of thermocompression bonding becomes smaller, and the thermosetting adhesive composition has better embedding property.

  Specific examples of the acrylic resin (B) include acrylic acid ester copolymers and methacrylic acid ester copolymers. These acrylic resins (B) may be used alone or in combination of two or more. Of these, acrylic acid ester copolymers are preferred. In this case, the thermosetting adhesive composition has more excellent flexibility.

  The acrylic resin (B) is blended at a ratio of 1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the polyester urethane resin (A). If the compounding quantity of the acrylic resin (B) with respect to 100 mass parts of polyester urethane resins (A) is less than 1 mass part, the embedding property of a thermosetting adhesive composition will fall. On the other hand, when the blending amount of the acrylic resin (B) with respect to 100 parts by mass of the polyester urethane resin (A) exceeds 50 parts by mass, leaching of the thermosetting adhesive composition at the time of curing by thermocompression bonding is sufficiently suppressed. I can't. The blending amount of the acrylic resin (B) with respect to 100 parts by mass of the polyester urethane resin (A) is preferably 5 parts by mass or more and 25 parts by mass or less with respect to 100 parts by mass of the polyester urethane resin (A).

(C) Epoxy resin An epoxy resin (C) should just have two or more epoxy groups in 1 molecule. Specific examples of the epoxy resin (C) include bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, biphenyl type epoxy resin, cresol novolac type epoxy resin, alicyclic epoxy resin, glycidyl ester type epoxy. Resins, glycidylamine type epoxy resins, hydantoin type epoxy resins, isocyanurate type epoxy resins, acrylic acid-modified epoxy resins (epoxy acrylates), phosphorus-containing epoxy resins, and their halides (such as brominated epoxy resins) and hydrogenated products Etc. These may be used alone or in combination of two or more.

  The epoxy resin (C) is blended at a ratio of 5 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the polyester urethane resin (A). When the blending amount of the epoxy resin (C) with respect to 100 parts by mass of the polyester urethane resin (A) is less than 5 parts by mass, the leaching of the thermosetting adhesive composition at the time of curing by thermocompression bonding can be sufficiently suppressed. Can not. On the other hand, when the compounding quantity of the epoxy resin (C) with respect to 100 mass parts of polyester urethane resins (A) becomes larger than 50 mass parts, the solder heat resistance of hardened | cured material will fall.

  Moreover, the thermosetting adhesive composition of the present invention may further contain a solvent and an additive as necessary. Examples of the additive include silica, mica, clay, talc, titanium oxide, calcium carbonate, a silane coupling agent, and imidazole.

<Coverlay film>
Next, an embodiment of the cover lay film of the present invention will be described in detail with reference to FIG. FIG. 1 is a cross-sectional view showing an embodiment of the coverlay film of the present invention.

  As shown in FIG. 1, the coverlay film 10 includes an insulating film 11 and an adhesive layer 12 provided on the insulating film 11, and the adhesive layer 12 uses the thermosetting adhesive composition. It is obtained.

  As the insulating film 11, for example, a resin such as a polyimide resin, a polyethylene terephthalate resin, or an aramid resin can be used. The thickness of the insulating film 11 is not particularly limited, but is usually about 3 μm to 50 μm.

  The adhesive layer 12 may be composed of the thermosetting adhesive composition, or may be composed of the thermosetting adhesive composition in a B stage state. In this specification, the B stage is an intermediate stage of the reaction of the thermosetting adhesive composition, and the thermosetting adhesive composition is softened and expanded by heating. A state in which even if it comes into contact with a liquid, it does not completely melt or dissolve.

  According to this coverlay film 10, the adhesive layer 12 is obtained by using a thermosetting adhesive composition having excellent adhesiveness to any of polyimide resin, copper and aluminum after curing. For this reason, in the case where the FPC is manufactured using the coverlay film 10, when the insulating film 11 is composed of a polyimide film, the insulating film 11 and the adhesive layer obtained by curing the adhesive layer 12 are used. Separation can be sufficiently suppressed. Moreover, according to the coverlay film 10, when the adhesive layer is bonded to the metal layer made of copper, peeling between the metal layer and the adhesive layer can be sufficiently suppressed. Furthermore, the said thermosetting adhesive composition also has the outstanding embedding property. For this reason, when manufacturing an FPC by bonding a metal-clad laminate to the coverlay film 10, the adhesive layer 12 obtained using the thermosetting adhesive composition is sufficiently in the gap formed in the metal layer. It becomes possible to be buried. For this reason, since the contact area between the metal layer and the adhesive layer 12 can be further increased, after the adhesive layer 12 is cured to form an adhesive layer, the separation between the adhesive layer and the metal layer is sufficiently performed. Can be suppressed. Further, the thermosetting adhesive composition has excellent solder heat resistance after curing. For this reason, when soldering an electronic component etc. with respect to FPC manufactured using the coverlay film 10, it can fully suppress that peeling arises in FPC when a swelling occurs in an adhesion layer. Furthermore, the thermosetting adhesive composition can sufficiently suppress leaching during curing by thermocompression bonding. For this reason, when manufacturing FPC by bonding the coverlay film 10 and the metal-clad laminate by thermocompression bonding, the leaching of the adhesive layer contained in the coverlay film 10 can be sufficiently suppressed.

  The coverlay film 10 is obtained by providing an adhesive layer 12 on an insulating film 11 and can be obtained by applying an adhesive solution containing a thermosetting adhesive composition on the insulating film 11 and drying it. it can.

<Adhesive film>
Next, an embodiment of the adhesive film of the present invention will be described in detail with reference to FIG. FIG. 2 is a cross-sectional view showing an embodiment of the adhesive film of the present invention.

  As shown in FIG. 2, the adhesive film 20 includes an adhesive layer 22 obtained by using the thermosetting adhesive composition.

  The adhesive layer 22 may be composed of the thermosetting adhesive composition, or may be composed of the thermosetting adhesive composition in a B stage state.

  As shown in FIG. 2, the adhesive film 20 may be composed of only the adhesive layer 22, and is composed of a laminate having the adhesive layer 22 on the carrier film subjected to the release treatment. It may be.

  As the carrier film, for example, polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate resin, or the like can be used.

  According to this adhesive film 20, the adhesive layer 22 is obtained by using a thermosetting adhesive composition having excellent adhesion to any of polyimide resin, copper and aluminum after curing. For this reason, when manufacturing FPC using the adhesive film 20, when the board | substrate which contacts the contact bonding layer obtained by hardening | curing the adhesive bond layer 22 is comprised with a polyimide film or an aluminum plate, the polyimide film or Peeling between the aluminum plate and the adhesive layer can be sufficiently suppressed. The thermosetting adhesive composition has excellent solder heat resistance after curing. For this reason, when manufacturing FPC using the adhesive film 20, when mounting an electronic component etc. with respect to the FPC, sufficiently suppressing occurrence of peeling in the FPC due to swelling of the adhesive layer. Can do. Furthermore, the thermosetting adhesive composition can sufficiently suppress leaching during curing by thermocompression bonding. For this reason, when manufacturing FPC by thermocompression bonding using the adhesive film 20, the leaching of the adhesive layer 22 can be sufficiently suppressed.

  The adhesive film 20 is obtained by applying an adhesive solution containing a thermosetting adhesive composition on a carrier film made of a polyethylene terephthalate film subjected to a release treatment and drying to obtain an adhesive layer 22. It can be obtained by peeling from the film. Alternatively, the adhesive film 20 is formed by applying an adhesive solution containing a thermosetting adhesive composition on a carrier film made of a polyethylene terephthalate film or the like that has been subjected to a release treatment, and then drying to form the adhesive layer 22. Can also be obtained.

<Metal-clad laminate>
Next, an embodiment of the metal-clad laminate of the present invention will be described in detail with reference to FIG. FIG. 3 is a cross-sectional view showing an embodiment of the metal-clad laminate of the present invention.

  As shown in FIG. 3, the metal-clad laminate 30 includes a base film 31, a metal layer 33 provided on one side of the base film 31, and an adhesive layer 32 provided between the base film 31 and the metal layer 33. And the adhesive layer 32 is obtained using the thermosetting adhesive composition.

  The adhesive layer 32 may be composed of the thermosetting adhesive composition, or may be composed of the thermosetting adhesive composition in the B stage state.

  As the base film 31, a resin film having electrical insulation and flexibility is used. For example, a resin such as polyimide resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyamide resin, polycarbonate resin, or polyethersulfone resin is used. It is done.

  As the metal layer 33, for example, a copper foil or the like is used.

  According to this metal-clad laminate 30, the adhesive layer 32 is obtained using a thermosetting adhesive composition having excellent solder heat resistance after curing. For this reason, when soldering an electronic component or the like to an FPC manufactured using the metal-clad laminate 30, the base film 31 and the base film 31 are formed by swelling of the adhesive layer obtained by curing the adhesive layer 32. It is possible to sufficiently suppress the occurrence of peeling between the adhesive layer. Moreover, the said thermosetting adhesive composition has the adhesiveness outstanding with respect to all of polyimide resin, copper, and aluminum after hardening. For this reason, when FPC is manufactured using the metal-clad laminate 30 and the adhesive layer 32 is made into an adhesive layer by curing, the base film 31 is formed when the base film 31 of the metal-clad laminate 30 is composed of a polyimide film. Can be sufficiently suppressed. Furthermore, when the metal layer 33 contains copper, peeling between the metal layer 33 and the adhesive layer can be sufficiently suppressed in the FPC. Moreover, the said thermosetting adhesive composition can fully suppress leaching at the time of hardening by thermocompression bonding. For this reason, when manufacturing FPC by bonding the metal-clad laminate 30 and the coverlay film, the leaching of the adhesive layer 32 can be sufficiently suppressed.

  The metal-clad laminate 30 is formed by sequentially providing an adhesive layer 32 and a metal layer 33 on a base film 31, and an adhesive solution containing a thermosetting adhesive composition is applied onto the base film 31 and dried. It can obtain by sticking the metal layer 33 on the adhesive bond layer 32 formed by doing.

<FPC>
Next, an embodiment of the FPC of the present invention will be described in detail with reference to FIG. FIG. 4 is a cross-sectional view showing a preferred embodiment of the FPC according to the present invention. As shown in FIG. 4, the FPC 100 includes a base film 31. An adhesive layer 132 is provided on the surface 31 a of the base film 31, a metal layer 33 that forms a circuit is provided on the adhesive layer 132, and an adhesive layer is provided on the adhesive layer 132 so as to cover the metal layer 33. 112 is provided, and the insulating film 11 is provided on the adhesive layer 112.

  On the other hand, a reinforcing material 40 is provided on the back surface 31 b of the base film 31 via an adhesive layer 122. The reinforcing material 40 is made of, for example, aluminum or polyimide resin.

  Next, a method for manufacturing the FPC 100 will be described with reference to FIG. FIG. 5 is a cross-sectional view showing a process of manufacturing the FPC of FIG.

  First, as shown in FIG. 5, first, a coverlay film 10, a metal-clad laminate 30, a reinforcing material 40, and an adhesive film 20 for bonding the metal-clad laminate 30 and the reinforcing material 40 together are prepared. .

  Then, the adhesive film 20, the metal-clad laminate 30, and the coverlay film 10 are sequentially disposed on the reinforcing material 40. At this time, the base film 31 of the metal-clad laminate 30 and the adhesive film 20 are made to face each other, and the adhesive layer 12 of the coverlay film 10, the adhesive layer 32 and the metal layer 33 of the metal-clad laminate 30, Are in a state of facing each other.

  And the reinforcing material 40, the adhesive film 20, the metal-clad laminated board 30, and the coverlay film 10 are laminated | stacked, a laminated body is formed, and this laminated body is thermocompression-bonded. As a result, the adhesive layer 12 of the coverlay film 10 is cured to become the adhesive layer 112, the adhesive layer 32 of the metal-clad laminate 30 is cured to become the adhesive layer 132, and the adhesive layer 22 of the adhesive film 20 is The adhesive layer 122 is cured. Thus, the FPC 100 is obtained.

  At this time, the adhesive layer 12 of the coverlay film 10, the adhesive layer 32 of the metal-clad laminate 30, and the adhesive layer 22 of the adhesive film 20 are thermosetting adhesive compositions having excellent solder heat resistance after curing. It is obtained using a product. For this reason, when soldering an electronic component or the like to the FPC 100, the adhesive layers 112, 122, 132 are swollen so that the insulating film 11, the base film 31, the reinforcing material 40, and the adhesive layers 112, 122, 132 It is possible to sufficiently suppress the occurrence of peeling. Moreover, since the adhesive layers 112, 122, and 132 are obtained by curing the adhesive layers 12, 22, and 32, they have excellent adhesion to any of polyimide resin, copper, and aluminum. For this reason, when the insulating film 11 and / or the base film 31 are composed of a polyimide film, the FPC 100 can sufficiently suppress the occurrence of peeling between the polyimide film and the adhesive layers 12, 22, and 32. it can. Furthermore, when the metal layer 33 includes copper in the FPC 100, peeling between the metal layer 33 and the adhesive layer can be sufficiently suppressed. Furthermore, when the reinforcing material 40 is comprised with a polyimide film or an aluminum plate, it can also fully suppress that peeling arises between the reinforcing material 40 and an contact bonding layer.

  Further, in the FPC 100, the metal-clad laminate 30 includes an adhesive layer 32 between the base film 31 and the metal layer 33, and the adhesive layer 32 is obtained using the thermosetting adhesive composition. . For this reason, the adhesive strength between the base film 31 and the metal layer 33 can be further improved.

  The present invention is not limited to the above embodiment. For example, in the said embodiment, although FPC100 is manufactured using the reinforcing material 40 and the adhesive film 20, these are not necessarily required and can be abbreviate | omitted. The adhesive layer 32 used for the metal-clad laminate 30 can also be omitted.

  In the above manufacturing method, the reinforcing material 40, the adhesive film 30, the metal-clad laminate 30, and the coverlay 10 are overlapped and the adhesive layers 12, 22, and 32 are cured together. The adhesive layer layers 12, 22, and 32 do not necessarily need to be cured at once. For example, the reinforcing material 40, the adhesive film 20, and the metal-clad laminate 30 are overlapped, and the adhesive layer 32 and the adhesive layer 22 of the adhesive film 20 are cured by thermocompression to obtain a laminate, and then the lamination is performed. The FPC 100 can also be obtained by overlapping the body and the coverlay film 10 and curing the adhesive layer 12.

  Hereinafter, the content of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

(Examples 1 to 21 and Comparative Examples 1 to 14)
A thermosetting adhesive composition was prepared as follows.

  That is, the polyester urethane resin (A), the acrylic resin (B), and the epoxy resin (C) are dissolved or dispersed in an organic solvent at a blending ratio shown in Tables 1 to 7 to obtain a solid content (polyester urethane resin (A), acrylic resin). An adhesive solution having a concentration of resin (B) and epoxy resin (C)) of 20% by mass was prepared. In addition, as an organic solvent, in each Example and the comparative example, at least 1 sort (s) was suitably selected and used among methyl ethyl ketone, xylene, and cyclohexanone 1-methoxy-2-propanol.

  In Tables 1 to 7, unless otherwise specified, the numerical unit represents parts by mass. Moreover, as the polyester urethane resin (A), the acrylic resin (B), and the epoxy resin (C), the following were specifically used. Further, the glass transition temperatures (hereinafter referred to as “Tg”) of the polyester urethane resin (A) and the acrylic resin (B) are measured in accordance with JIS K7121, and the hydroxyl value of the polyester urethane resin (A) is measured. Is measured according to JIS K0070.

(A) Polyester urethane resin (A1) Polyester urethane resin (A1-1) Polyester urethane resin: Trade name “UR-4410”, manufactured by Toyobo Co., Ltd., Tg = 56 ° C., hydroxyl value = 11 KOHmg / g
(A1-2) Polyester urethane resin: trade name “UR-5537”, manufactured by Toyobo Co., Ltd., Tg = 34 ° C., hydroxyl value = 18 KOHmg / g
(A1-3) Polyester urethane resin: Trade name “UR-1350”, manufactured by Toyobo Co., Ltd., Tg = 46 ° C., hydroxyl value = 3 KOHmg / g
(A1-4) Polyester urethane resin: Trade name “UR-8200”, manufactured by Toyobo Co., Ltd., Tg = 73 ° C., hydroxyl value = 5 KOHmg / g
(A2) Polyester urethane resin (A2-1) Polyester urethane resin: Trade name “UR-3500”, manufactured by Toyobo Co., Ltd., Tg = 10 ° C., hydroxyl value = 10 KOHmg / g
(A2-2) Polyester urethane resin: Trade name “UR-8700”, manufactured by Toyobo Co., Ltd., Tg = −22 ° C., hydroxyl value = 3 KOHmg / g
(A2-3) Polyester urethane resin: Trade name “UR-3200”, manufactured by Toyobo Co., Ltd., Tg = −3 ° C., hydroxyl value = 2 KOHmg / g
(A2-4) Polyester urethane resin: trade name “UR-3575”, manufactured by Toyobo Co., Ltd., Tg = 25 ° C., hydroxyl value = 5 KOHmg / g
(A2-5) Polyester urethane resin: Trade name “UR-8300”, manufactured by Toyobo Co., Ltd., Tg = 23 ° C., hydroxyl value = 3 KOHmg / g
(A3) Polyester urethane resin (A3-1) Polyester urethane resin: Trade name “UR-1400”, manufactured by Toyobo Co., Ltd., Tg = 83 ° C., hydroxyl value = 2 KOHmg / g
(A3-2) Polyester urethane resin: Trade name “UR-1700”, manufactured by Toyobo Co., Ltd., Tg = 92 ° C., hydroxyl value = 19 KOHmg / g
(A3-3) Polyester urethane resin: Trade name “UR-4800”, manufactured by Toyobo Co., Ltd., Tg = 106 ° C., hydroxyl value = 5 KOHmg / g
(A3-4) Polyester urethane resin: Trade name “UR-6100”, manufactured by Toyobo Co., Ltd., Tg = −30 ° C., hydroxyl value = 5 KOHmg / g

(B) Acrylic resin (B-1) Acrylic resin: Trade name “UP-1010”, manufactured by Toagosei Co., Ltd., Tg = −31 ° C.
(B-2) Acrylic resin: Trade name “UP-1080”, manufactured by Toagosei Co., Ltd., Tg = −61 ° C.
(B-3) Acrylic resin: Trade name “BR-1122”, manufactured by Mitsubishi Rayon Co., Ltd., Tg = 20 ° C.
(B-4) Acrylic resin: Trade name “BR-117”, manufactured by Mitsubishi Rayon Co., Ltd., Tg = 34 ° C.
(B-5) Acrylic resin: Trade name “UP-1020”, manufactured by Toagosei Co., Ltd., Tg = −80 ° C.
(B-6) Acrylic resin: Trade name “BR-90”, manufactured by Mitsubishi Rayon Co., Ltd., Tg = 65 ° C.

(C) Epoxy resin o-cresol novolac type epoxy resin, trade name “YDCN-704”, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.

[Evaluation]
About the thermosetting adhesive composition obtained in Examples 1-21 and Comparative Examples 1-14, adhesiveness to polyimide resin (PI) after curing, copper (Cu) and aluminum (Al), solder after curing The heat resistance, storage stability, embedding property, and leachability upon curing by thermocompression bonding were evaluated as follows.

<Production of metal-clad laminate>
First, a metal-clad laminate (hereinafter referred to as “CCL”) used for the following evaluation was produced as follows.

  That is, on the polyimide film having a thickness of 25 μm, the thermosetting adhesive compositions obtained in Examples 1 to 21 and Comparative Examples 1 to 14 were applied and dried so that the thickness after drying was 10 μm. After obtaining the adhesive layer, a rolled copper foil having a thickness of 18 μm was bonded to the adhesive layer to obtain CCL.

<Adhesiveness>
(Adhesive strength to PI)
The adhesive film comprised by the 25-micrometer-thick adhesive layer formed by apply | coating and drying the thermosetting adhesive composition obtained in Examples 1-21 and Comparative Examples 1-14 was prepared. On the other hand, a polyimide sheet having a thickness of 125 μm was prepared. And the said adhesive film is pinched | interposed between the said polyimide film of CCL, and the said polyimide sheet, a laminated body is formed, and this laminated body is thermocompression bonded at 160 degreeC and 55 kg / cm < ² > for 60 minutes, and adhesive layer Was cured by thermocompression bonding to form an adhesive layer. In this way, a sample for evaluation was produced.

  In this evaluation sample, the CCL polyimide film was pulled in a direction perpendicular to the polyimide sheet, and the peel strength (90 ° peel strength) at this time was measured as the adhesive strength to PI (adhesive strength (vs. PI)). did. The results are shown in Tables 1-7.

(Peeling resistance test (vs. PI))
In order to investigate the significance of the above-described adhesive strength (vs. PI), the peel resistance test (vs. PI) of the thermosetting adhesive compositions obtained in Examples 1 to 21 and Comparative Examples 1 to 14 was as follows. )

That is, first, the thermosetting adhesive compositions obtained in Examples 1 to 21 and Comparative Examples 1 to 14 were applied on a polyimide film having a thickness of 25 μm so that the thickness after drying was 20 μm, and dried to be bonded. An agent layer was formed to obtain a coverlay film. Then, the cover lay film and the CCL are bonded together so that the adhesive layer of the cover lay film and the copper foil of the CCL face each other to form a laminate, and this laminate is 160 ° C., 55 kg. After thermocompression bonding at / cm ² for 60 minutes, a 10 mm × 50 mm × 108 μm test piece was cut out.

  On the other hand, the thermosetting adhesive compositions obtained in Examples 1 to 21 and Comparative Examples 1 to 14 were applied so as to have a thickness of 25 μm after drying and dried to form an adhesive layer having a thickness of 25 μm. An adhesive film was prepared.

  On the other hand, a polyimide sheet of 10 mm × 20 mm × 125 μm was prepared.

And the said adhesive film was pinched | interposed in the state which faced the said polyimide sheet and the polyimide film of the said test piece between the said polyimide sheet and the said test piece, and formed the laminated body. At this time, the polyimide sheet and the test piece were laminated so that their longitudinal directions coincided. Moreover, the said polyimide sheet laminated | stacked on the part of 10 mm x 20 mm of one side from the line | wire of the direction orthogonal to the longitudinal direction of the said polyimide film, when the said test piece is seen from the polyimide film side. And this laminated body was thermocompression bonded at 160 degreeC and 55 kg / cm < ² > for 60 minutes, the adhesive bond layer was hardened, and it was set as the contact bonding layer. In this way, a sample for evaluation was produced.

  When the sample for evaluation is viewed from the polyimide sheet side, at the boundary line between the polyimide sheet and the test piece, the test piece is 180 ° so that the curvature radius r becomes 1 mm and overlaps the test piece. Bent. At that time, it was examined whether peeling occurred between the polyimide sheet and the test piece. The results are shown in Tables 1-7. In Tables 1 to 7, for the thermosetting adhesive composition where peeling did not occur, “◯” was indicated as being excellent in adhesion to PI after curing, and the thermosetting adhesive composition where peeling occurred. Was marked as “x” because it was not excellent in adhesion to PI after curing.

  From the results of the above peel resistance test, the thermosetting adhesive composition having a 90 ° peel strength of 15 N / cm or more after curing has excellent adhesiveness to PI after curing, and 90 ° It was found that the thermosetting adhesive composition having a peel strength of less than 15 N / cm does not have excellent adhesiveness to PI after curing.

(Adhesive strength to Cu)
On the polyimide film having a thickness of 25 μm, the thermosetting adhesive compositions obtained in Examples 1 to 21 and Comparative Examples 1 to 14 were applied so that the thickness after drying was 25 μm, and dried to be bonded. An agent layer was obtained. Thus, a coverlay film (hereinafter referred to as “CL”) was produced. Next, the CL and the CCL are bonded together so that the CL adhesive layer and the CCL copper foil face each other to form a laminate, and the laminate is heated at 160 ° C. and 55 kg / cm ² . The CL adhesive layer and the CCL adhesive layer were cured by thermocompression bonding for 60 minutes to form an adhesive layer. In this way, a sample for evaluation was produced.

  In this evaluation sample, the CCL was pulled in a direction perpendicular to the CL, and the peel strength (90 ° peel strength) at this time was measured as the adhesive strength to Cu (adhesive strength (vs. Cu)). The results are shown in Tables 1-5.

(Peeling resistance test (vs. Cu))
In order to investigate the significance of the above-described adhesive strength (vs. Cu), the peel resistance test (vs. Cu) of the thermosetting adhesive compositions obtained in Examples 1 to 21 and Comparative Examples 1 to 14 was performed as follows. )

  That is, first, a test piece used in the peel resistance test (vs. PI) was prepared.

  On the other hand, the adhesive film comprised by the 25-micrometer-thick adhesive layer formed by apply | coating and drying the thermosetting adhesive composition obtained in Examples 1-21 and Comparative Examples 1-14 was produced.

  On the other hand, a 10 mm × 20 mm × 35 μm copper plate was prepared.

And the said adhesive film was pinched | interposed in the state which faced the said copper plate and the polyimide film of the said test piece between the said copper plate and the said test piece, and the laminated body was formed. At this time, the copper plate and the test piece were laminated so that their longitudinal directions coincided. Moreover, the said copper plate was laminated | stacked on the part of 10 mm x 20 mm of one side from the line | wire of the direction orthogonal to the longitudinal direction of the polyimide film, when the said test piece is seen from the polyimide film side. And this laminated body was thermocompression bonded at 160 degreeC and 55 kg / cm < ² > for 60 minutes, the adhesive bond layer was hardened, and it was set as the contact bonding layer. In this way, a sample for evaluation was produced.

  When the sample for evaluation is viewed from the copper plate side, the test piece is bent by 180 ° so that the curvature radius r becomes 1 mm and overlaps the test piece at the boundary line between the copper plate and the test piece. . At that time, it was examined whether peeling occurred between the copper plate and the test piece. The results are shown in Tables 1-7. In Tables 1 to 7, for the thermosetting adhesive composition in which peeling did not occur, “◯” was indicated as being excellent in adhesion to Cu after curing, and the thermosetting adhesive composition in which peeling occurred. Was marked as “x” because it was not excellent in adhesion to Cu after curing.

  From the results of the above peel resistance test, the thermosetting adhesive composition having a 90 ° peel strength of 15 N / cm or more after curing has excellent adhesiveness to Cu after curing, and 90 ° It was found that the thermosetting adhesive composition having a peel strength of less than 15 N / cm does not have excellent adhesion to Cu after curing.

(Adhesive strength to Al)
The adhesive film comprised by the 25-micrometer-thick adhesive layer formed by apply | coating and drying the thermosetting adhesive composition obtained in Examples 1-21 and Comparative Examples 1-14 was prepared. On the other hand, an aluminum plate having a thickness of 100 μm was prepared. Then, a laminate is formed by sandwiching the adhesive film between the CCL polyimide film and the aluminum plate, and the laminate is thermocompression bonded at 160 ° C. and 55 kg / cm ² for 60 minutes to obtain an adhesive. The layer was cured by thermocompression bonding to form an adhesive layer. In this way, a sample for evaluation was produced.

  In this evaluation sample, the CCL polyimide film was pulled in a direction perpendicular to the aluminum plate, and the peel strength (90 ° peel strength) at this time was measured as the adhesive strength to Al (adhesive strength (vs. Al)). . The results are shown in Tables 1-7.

(Peeling resistance test (vs. Al))
In order to investigate the significance of the above-described adhesive strength (vs. Al), the thermosetting adhesive compositions obtained in Examples 1 to 21 and Comparative Examples 1 to 14 were peeled off as described below (vs. Al). )

  That is, first, a test piece used in the peel resistance test (vs. PI) was prepared.

  On the other hand, the adhesive film comprised by the 25-micrometer-thick adhesive layer formed by apply | coating and drying the thermosetting adhesive composition obtained in Examples 1-21 and Comparative Examples 1-14 was produced.

  On the other hand, an aluminum plate of 10 mm × 20 mm × 100 μm was prepared.

And the said adhesive film was pinched | interposed in the state which faced the said aluminum plate and the polyimide film of the said test piece between the said aluminum plate and the said test piece, and the laminated body was formed. At this time, the aluminum plate and the test piece were laminated so that their longitudinal directions coincided. Moreover, the said aluminum plate laminated | stacked on the part of 10 mm x 20 mm of one side from the line | wire of the direction orthogonal to the longitudinal direction of the polyimide film, when the said test piece is seen from the polyimide film side. And this laminated body was thermocompression bonded at 160 degreeC and 55 kg / cm < ² > for 60 minutes, the adhesive bond layer was hardened, and it was set as the contact bonding layer. In this way, a sample for evaluation was produced.

  When the sample for evaluation is viewed from the aluminum plate side, at the boundary line between the aluminum plate and the test piece, the test piece is 180 ° so that the curvature radius r is 1 mm and overlaps the test piece. Bent. And it was investigated whether peeling had arisen between the said aluminum plate and the said test piece at that time. The results are shown in Tables 1-7. In Tables 1 to 7, for the thermosetting adhesive composition in which peeling did not occur, “◯” was indicated as being excellent in adhesion to Al after curing, and the thermosetting adhesive composition in which peeling occurred. Is marked as “x” because the adhesiveness to Al is not excellent after curing.

  From the results of the above peel resistance test, the thermosetting adhesive composition having a 90 ° peel strength of 15 N / cm or more after curing has excellent adhesiveness to Al after curing, and 90 ° It was found that the thermosetting adhesive composition having a peel strength of less than 15 N / cm does not have excellent adhesiveness to Al after curing.

<Solder heat resistance>
First, the thermosetting adhesive composition obtained in Examples 1 to 21 and Comparative Examples 1 to 14 was applied on a polyimide film having a thickness of 25 μm and dried to form an adhesive layer having a thickness of 20 μm. Thus, CL was prepared. Then, the CL and the CCL are bonded together so that the CL adhesive layer and the copper foil face each other to form a laminated body, and the laminated body is thermocompression bonded at 160 ° C. and 55 kg / cm ² for 60 minutes. The CL adhesive layer and the CCL adhesive layer were cured by thermocompression bonding to form an adhesive layer, and then cut into 25 mm squares as sample for evaluation.

  Then, this sample for evaluation was placed in an oven at 105 ° C. for 1 hour, and immediately after taking out from the oven, it was floated in a solder bath at 260 ° C. for 60 seconds to examine whether the adhesive layer was swollen or peeled off. The results are shown in Tables 1-7. In Tables 1 to 7, an evaluation sample in which no swelling or peeling occurs in the adhesive layer is indicated as “◯” as being excellent in solder heat resistance, and the evaluation sample in which swelling or peeling occurs in the adhesive layer “X” is indicated as not having excellent solder heat resistance.

<Storage stability>
The thermosetting adhesive compositions obtained in Examples 1 to 21 and Comparative Examples 1 to 14 were refrigerated (5 ° C. or lower) and applied to a polyimide film having a thickness of 25 μm after 7 days. At this time, it was examined whether there was any problem in coating property. The results are shown in Tables 1-7. In Tables 1 to 7, the thermosetting adhesive composition having no problem in coating property is indicated as “◯” as being excellent in storage stability, and the thermosetting adhesion that is difficult to apply by gelation. The agent composition was indicated as “x” because it was not excellent in storage stability.

<Embedding property>
A comb pattern of L (line) / S (space) = 50 μm / 50 μm was formed on the CCL copper foil. On the other hand, the thermosetting adhesive composition obtained in Examples 1 to 21 and Comparative Examples 1 to 14 was applied on a polyimide film having a thickness of 25 μm and dried to form an adhesive layer having a thickness of 20 μm. In this way, CL was prepared. Then, the CCL and the CL are bonded together so that the copper foil of the CCL and the adhesive layer of the CL face each other to form a laminated body. The laminated body is 60 ° C. at 160 ° C. and 55 kg / cm ² . Thermocompression bonding was performed for a minute. Thus, an evaluation sample was obtained. The sample for evaluation was observed with a microscope, and it was examined whether bubbles were observed between the lines of the comb pattern. The results are shown in Tables 1-7. At this time, the microscopic observation of the evaluation sample was performed by observing the evaluation sample in the thickness direction. In Tables 1 to 7, the thermosetting adhesive composition in which bubbles were observed is indicated as “x” as being inferior in embedding property, and the thermosetting adhesive composition in which bubbles were not observed is embedded. “○” is indicated as being excellent in performance.

<Leachability when cured by thermocompression bonding>
On the polyimide film having a thickness of 25 μm, the thermosetting adhesive compositions obtained in Examples 1 to 21 and Comparative Examples 1 to 14 were applied and dried so that the thickness after drying was 20 μm. After obtaining the layer, 10 punch holes with a diameter of 5 mm were made. A laminated body was formed by laminating a rolled copper foil having a thickness of 18 μm on the adhesive layer. The laminate was subjected to thermocompression bonding at 160 ° C. and 55 kg / cm ² for 60 minutes to obtain an evaluation sample. Then, the maximum leaching distance of the adhesive layer into the punch hole was measured for all 10 places in the obtained sample for evaluation, and the average distance was defined as the adhesive flow distance. The results are shown in Tables 1-7. In addition, if the adhesive flow distance at the time of thermocompression bonding was 0.10 mm or less, it was evaluated that the leaching of the adhesive layer at the time of curing by thermocompression bonding was sufficiently suppressed, and was regarded as acceptable. Moreover, when the adhesive flow distance at the time of thermocompression bonding was larger than 0.10 mm, it judged that the leaching of the adhesive layer at the time of curing by thermocompression bonding was not sufficiently suppressed, and was rejected.

  From the results shown in Tables 1 to 7, the thermosetting adhesive compositions obtained in Examples 1 to 21 are storage stability, embedding property, cured polyimide resin, adhesion to copper and aluminum, and after curing. It has been found that the soldering heat resistance and the leaching control property during curing by thermocompression bonding have passed the acceptance standards. On the other hand, the thermosetting adhesive compositions obtained in Comparative Examples 1 to 14 are storage stability, embedding property, cured polyimide resin, adhesion to copper and aluminum, solder heat resistance after curing, In addition, it has been found that the acceptance criteria are not reached in at least one point of leaching suppression during curing by thermocompression bonding.

  From the above, according to the thermosetting adhesive composition of the present invention, it has excellent storage stability and embedding property, can sufficiently suppress leaching during curing by thermocompression bonding, and after curing It was confirmed that it was possible to have excellent solder heat resistance while having excellent adhesion to any of polyimide resin, copper and aluminum.

DESCRIPTION OF SYMBOLS 10 ... Cover-lay film 11 ... Insulating film 12, 22, 32 ... Adhesive layer 20 ... Adhesive film 30 ... Metal-clad laminate 31 ... Base film 33 ... Metal layer 40 ... Reinforcement material 100 ... FPC
112, 122, 132 ... adhesive layer

Claims (7)

For 100 parts by mass of polyester urethane resin (A),
The acrylic resin (B) is blended at a ratio of 1 part by mass or more and 50 parts by mass or less,
The epoxy resin (C) is blended at a ratio of 5 parts by mass or more and 50 parts by mass or less,
The polyester urethane resin (A) is
A polyester urethane resin (A1) having a glass transition temperature of 30 ° C. or more and 100 ° C. or less and having a hydroxyl value of 3 KOH mg / g or more and 18 KOH mg / g or less;
A polyester urethane resin (A2) having a glass transition temperature of −25 ° C. or higher and lower than 30 ° C.,
The content of the polyester urethane resin (A1) in a total of 100% by mass of the polyester urethane resin (A1) and the polyester urethane resin (A2) is 50% by mass to 95% by mass,
A thermosetting adhesive composition in which the acrylic resin (B) has a glass transition temperature of from -70 ° C to 50 ° C. An insulating film;
An adhesive layer provided on the insulating film,
The coverlay film obtained by using the thermosetting adhesive composition according to claim 1, wherein the adhesive layer.   The adhesive film containing the adhesive bond layer obtained using the thermosetting adhesive composition of Claim 1. A base film,
A metal layer provided on one side of the base film;
An adhesive layer provided between the base film and the metal layer;
A metal-clad laminate obtained by using the thermosetting adhesive composition according to claim 1, wherein the adhesive layer is used.   A metal-clad laminate in which a metal layer is provided on one surface side of the base film; and the coverlay film according to claim 2; the adhesive layer of the coverlay film; and the metal layer of the metal-clad laminate. A flexible printed circuit board that is thermocompression-bonded with the two facing each other.   A reinforcing material, a metal-clad laminate in which a metal layer is provided on one surface side of the base film, and a coverlay film according to claim 2, wherein the adhesive layer of the coverlay film and the metal-clad laminate The heat of claim 1, wherein the adhesive film is thermocompression-bonded with an adhesive film interposed between the reinforcing material and the metal-clad laminate, with the metal layer facing each other. A flexible printed wiring board obtained using a curable adhesive composition.   The metal-clad laminate is provided with an adhesive layer between the base film and the metal layer, and the adhesive layer is obtained using the thermosetting adhesive composition according to claim 1. The flexible printed wiring board according to 5 or 6.

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