JP2012012525A - Adhesive composition, adhesive film, and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive composition which can realize an adhesive film and also control flow out during press cure while showing outstanding soldering heat resistance, and to provide the adhesive film and a method of manufacturing the same.SOLUTION: The adhesive composition includes (A) an acrylic resin, (B) an epoxy resin, (C) a first curing agent, and (D) a second curing agent, wherein the second curing agent has lower reaction initiating temperature than that of the first curing agent, the epoxy resin (B) is blended at the rate of 12.5-50 parts by mass based on 100 parts by mass of the acrylic resin (A), the first curing agent (C) is blended at the rate of 0.05-0.5 part by mass based on to 100 parts by mass of the acrylic resin, and the second curing agent (D) is blended so as to cause the number of a reactive group to account for 20-70% of the number of a reactive group of the epoxy resin (B).

Description

  The present invention relates to an adhesive composition, an adhesive film, and a method for producing the same.

  A flexible printed circuit (FPC) is often used in an electronic device such as a hard disk device or a mobile phone by taking advantage of its flexibility. As FPC, a metal-clad laminate and a coverlay are thermocompression bonded via an adhesive film, and a reinforcing plate made of polyimide or metal is further provided on the back side of the metal-clad laminate via an adhesive film. FPC is also known.

  In such FPC, as an adhesive film, an adhesive film in which an acrylic adhesive composition excellent in solder heat resistance is made into a semi-cured state is widely used. For example, Patent Document 1 below discloses an acrylic adhesive composition including a curing agent such as an acrylic resin, an epoxy resin, a phenol resin, a polyamidoamine, and diamidoamine as an acrylic adhesive composition.

JP 2002-265906 A

  By the way, as an adhesive film for FPC, an adhesive film that exhibits excellent soldering heat resistance to polyimide and metal and has a small flow of adhesive during press curing is desirable.

  However, the adhesive composition described in Patent Document 1 described above has a problem that even if the adhesive composition is semi-cured to form an adhesive film, the adhesive film easily flows out due to heat and pressure during press curing, and exudes larger than the adhesion site. Had. This oozing-out portion may cause a problem in the electronic device when the FPC is incorporated into the electronic device. For example, when the FPC is incorporated in a hard disk device, the seepage part may be separated from the FPC and adhere to the hard disk, thereby hindering normal operation of the hard disk device.

  Therefore, there has been a demand for an adhesive composition that can realize an adhesive film that exhibits excellent solder heat resistance and can also suppress flow out during press curing.

  The present invention has been made in view of the above circumstances, and can provide an adhesive composition, an adhesive film, and a production thereof that can realize an adhesive film that exhibits excellent solder heat resistance and can also suppress flow out during press curing. It aims to provide a method.

  As a result of intensive studies to solve the above problems, the inventor has found that the ratio of the number of reactive groups of the polyamidoamine to the number of reactive groups of the epoxy resin is small in the adhesive composition described in Patent Document 1 above. It was thought that it might be one of the causes that the adhesive flowed out easily during curing. That is, since the ratio of the reactive group of the polyamidoamine to the number of reactive groups of the epoxy resin is small, the epoxy resin is not sufficiently cured at the time of press curing, and the adhesive composition is not softened. It was thought that the flow-out amount of the adhesive composition would increase. As a result of further earnest research, the inventor made the ratio of the reactive group of the second curing agent to the number of reactive groups of the epoxy resin in the adhesive composition within a predetermined range, and the epoxy resin and the second curing agent. It discovered that the said subject could be solved by mix | blending the 1st hardening | curing agent which has a lower reaction start temperature with a predetermined ratio with respect to an acrylic resin, and came to complete this invention.

  That is, the present invention includes (A) an acrylic resin, (B) an epoxy resin, (C) a first curing agent, and (D) a second curing agent, and the second curing agent (D) includes the above-mentioned The epoxy resin (B) has a reaction start temperature lower than that of the first curing agent (C), and is blended at a ratio of 12.5 to 50 parts by mass with respect to 100 parts by mass of the acrylic resin (A). Said 1st hardening | curing agent (C) is mix | blended in the ratio of 0.05-0.5 mass part with respect to 100 mass parts of said acrylic resins (A), and said 2nd hardening | curing agent (D) is said epoxy resin. (B) It is mix | blended so that it may have 20-70% of reactive group number of the reactive group number, It is an adhesive composition characterized by the above-mentioned.

  When this adhesive composition is placed at a temperature equal to or higher than the reaction start temperature of the second hardener and lower than the reaction start temperature of the first hardener, the epoxy resin and the second hardener are sufficiently reacted. It becomes possible to realize a sufficiently hard adhesive film. For this reason, even if it press-cure, the adhesive film which can fully suppress a flow-out is realizable. Moreover, since the adhesive composition of the present invention contains an appropriate amount of the first curing agent having a higher reaction start temperature than the second curing agent, the epoxy resin and the first resin are subjected to press curing at a temperature equal to or higher than the reaction initiation temperature of the first curing agent. It is also possible to realize an adhesive film that can be sufficiently cured by reacting with a curing agent and that can impart excellent solder heat resistance.

  Moreover, this invention arrange | positions the said adhesive composition under the temperature lower than the reaction start temperature of the said 1st hardening | curing agent (C) above the reaction start temperature of the said 2nd hardening | curing agent (D). It is a manufacturing method of an adhesive film including a step of forming an adhesive and a step of applying an adhesive solution containing the adhesive on a substrate and drying it to form an adhesive film.

  According to this production method, the adhesive composition is placed at a temperature equal to or higher than the reaction start temperature of the second curing agent and lower than the reaction start temperature of the first curing agent. It becomes possible to sufficiently react with the curing agent, and it becomes possible to realize a sufficiently hard adhesive film. For this reason, even if it press-cures, the adhesive film which can fully suppress a flow out is realizable. Moreover, since the said adhesive composition contains a suitable amount of 1st hardening | curing agents whose reaction start temperature is higher than a 2nd hardening | curing agent, an epoxy resin and 1st hardening are carried out by the press cure by the temperature beyond the reaction start temperature of a 1st hardening | curing agent. It is possible to obtain an adhesive film that can be sufficiently cured by reacting with an agent and that can impart excellent solder heat resistance.

  Furthermore, this invention is an adhesive film obtained by the manufacturing method of the said adhesive film.

  According to this adhesive film, even if it is press-cured, the flow-out can be sufficiently suppressed. Moreover, since the said adhesive film contains a suitable quantity of 1st hardening | curing agents whose reaction start temperature is higher than a 2nd hardening | curing agent, an epoxy resin and a 1st hardening | curing agent are carried out by the press cure by the temperature beyond the reaction start temperature of a 1st hardening | curing agent. Can be cured sufficiently, and thereby excellent solder heat resistance can be imparted to the resulting adhesive layer.

  In the present invention, “reaction start temperature” refers to a temperature at which heat is generated by the reaction between the first curing agent or the second curing agent and the epoxy resin in the differential scanning calorimetry.

  ADVANTAGE OF THE INVENTION According to this invention, the adhesive composition which can implement | achieve the adhesive film which can also suppress the outflow at the time of press cure while exhibiting the outstanding solder heat resistance, an adhesive film, and its manufacturing method are provided.

It is sectional drawing which shows an example of the flexible printed wiring board manufactured using the adhesive film which concerns on this invention. It is sectional drawing which shows components required for manufacture of the flexible printed wiring board of FIG.

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

  FIG. 1 is a cross-sectional view showing an example of a flexible printed wiring board manufactured using an adhesive film according to the present invention. As shown in FIG. 1, the flexible printed wiring board 100 includes a base film 1. An adhesive layer 2 is provided on the surface 1 a of the base film 1, a metal layer 3 for forming a circuit is provided on the adhesive layer 2, and an adhesive layer is provided on the adhesive layer 2 so as to cover the metal layer 3. 4 is provided, and an insulating film 5 is provided on the adhesive layer 4.

  On the other hand, a reinforcing plate 7 is provided on the back surface 1 b of the base film 1 via an adhesive layer 6. The reinforcing plate 7 is made of stainless steel, polyimide, or the like.

  Next, a method for manufacturing the flexible printed wiring board 100 will be described with reference to FIG. FIG. 2 is a cross-sectional view showing components necessary for manufacturing the flexible printed wiring board of FIG.

  First, as shown in FIG. 2, a cover lay 10, a metal-clad laminate 20, a reinforcing plate 7, and an adhesive film 30 for bonding the metal-clad laminate 20 and the reinforcing plate 7 are prepared.

  The coverlay 10 is formed by providing an adhesive layer 14 on the insulating film 5 and can be obtained by applying an adhesive solution containing an adhesive composition on the insulating film 5 and drying it. For this reason, the adhesive layer 14 is in a state where a part of the adhesive composition is cured, for example, in a semi-cured state. As the insulating film 5, for example, a film made of polyimide resin, polyethylene terephthalate resin, aramid resin or the like and having a thickness of about 3 μm to 50 μm can be used.

  The metal-clad laminate 20 is obtained by sequentially providing an adhesive layer 22 and a metal layer 3 on the base film 1, and applying an adhesive solution containing an adhesive composition on the base film 1 and drying it. It can be obtained by sticking the metal layer 3 on the formed adhesive layer 22. Here, the adhesive layer 22 is in a state where a part of the adhesive composition is cured, for example, in a semi-cured state. As the base film 1, a resin film having electrical insulation and flexibility is used, and examples thereof include films made of resins such as polyimide, polyethylene terephthalate, polybutylene terephthalate, polyamide, polycarbonate, and polyethersulfone. The metal layer 3 is made of copper foil or the like.

  The adhesive film 30 can be obtained as follows.

  First, an adhesive composition is prepared. As an adhesive composition, what contains (A) acrylic resin, (B) epoxy resin, (C) 1st hardening | curing agent, and (D) 2nd hardening | curing agent is prepared. Here, what has a reaction start temperature lower than a 1st hardening | curing agent (C) is used as a 2nd hardening | curing agent (D), and an epoxy resin (B) is 100 mass parts of acrylic resins (A). 12.5 to 50 parts by mass, the first curing agent (C) is compounded at a rate of 0.05 to 0.5 parts by mass with respect to 100 parts by mass of the acrylic resin (A). 2 The curing agent (D) is blended so as to have a reactive group number of 20 to 70% of the reactive group number of the epoxy resin (B).

  And this adhesive composition is melt | dissolved in a solvent, and it arrange | positions under the temperature lower than the reaction start temperature of the 1st hardening | curing agent (C) above the reaction start temperature of a 2nd hardening | curing agent (D). For this purpose, for example, an adhesive composition dissolved in a solvent may be heated to reflux. Thereby, the 2nd hardening | curing agent (D) in an adhesive composition and an epoxy resin (B) are made to react, and the adhesive agent solution containing an adhesive agent is obtained.

  Next, this adhesive solution is applied onto a substrate made of a polyethylene terephthalate film or the like that has been subjected to a release treatment and dried. Thus, the adhesive film 30 is obtained on the substrate.

  Next, the adhesive film 30, the metal-clad laminate 20, and the coverlay 10 are sequentially stacked on the reinforcing plate 7. At this time, the base film 1 of the metal-clad laminate 20 and the adhesive film 30 are made to face each other, and the adhesive layer 14 of the coverlay 10, the adhesive layer 22 and the metal layer 3 of the metal-clad laminate 20 are combined. It is in a state of facing each other. When the adhesive film 30 is superimposed on the reinforcing plate 7, the substrate is peeled after the adhesive film with the substrate is superimposed on the reinforcing plate 7. However, the adhesive film 30 may be peeled off from the adhesive film with the substrate and may be superposed on the reinforcing plate 7.

  And the reinforcement board 7, the adhesive film 30, the metal-clad laminated board 20, and the coverlay 10 are thermocompression-bonded. Thereby, the adhesive layer 14 of the coverlay 10, the adhesive layer 22 of the metal-clad laminate 20, and the adhesive film 30 are press-cured. At this time, the temperature of the press cure is set to be equal to or higher than the reaction start temperature of the first curing agent. In addition, the adhesive film 30 is sufficiently hard because the epoxy resin and the second curing agent are sufficiently reacted before press curing. For this reason, even if it press-cure, the flow-out of the adhesive film 30 can fully be suppressed. In addition, since the adhesive film 30 contains an appropriate amount of the first curing agent having a higher reaction start temperature than the second curing agent, the epoxy resin and the first curing agent are subjected to press curing at a temperature equal to or higher than the reaction initiation temperature of the first curing agent. Can be reacted. As a result, the adhesive film 30 is sufficiently cured, and the obtained adhesive layer 6 has excellent solder heat resistance.

  Thus, the adhesive layer 14 of the cover lay 10 is further cured to become the adhesive layer 4, the adhesive layer 22 of the metal-clad laminate 20 is further cured to become the adhesive layer 2, and the adhesive film 30 is further cured to adhere. Layer 6 is formed. Thus, the flexible printed wiring board 100 is obtained. In the flexible printed wiring board 100, the adhesive layer 6 has excellent solder heat resistance. For this reason, even if an electronic component or the like is mounted, swelling or the like hardly occurs in the adhesive layer 6. Moreover, the flexible printed wiring board 100 is manufactured using the adhesive film 30 which can suppress the flow-out at the time of press curing. For this reason, even if such a flexible printed wiring board 100 is incorporated in an electronic device such as a hard disk device, the protruding portion of the adhesive layer 6 sufficiently prevents the normal operation of the electronic device from being hindered.

  Next, the adhesive composition used for manufacturing the adhesive sheet 30 will be described in more detail.

(A) Acrylic resin The acrylic resin can be used without particular limitation as long as it has an acrylic ester as a monomer unit and can impart flexibility to the epoxy resin. As such an acrylic resin, for example, a homopolymer of alkyl (meth) acrylate, a copolymer of at least one alkyl (meth) acrylate and acetonitrile, or a functional group such as a carboxyl group or an epoxy group is introduced into them. An acrylic resin etc. are mentioned. Here, examples of the alkyl (meth) acrylate include ethyl acrylate, butyl acrylate, and methyl methacrylate. The said acrylic resin may be used independently and may use 2 or more types together. Among them, an acrylic resin into which a carboxyl group is introduced is preferable because it has reactivity with an epoxy resin. Examples of the acrylic resin having a carboxyl group introduced include acrylic resins modified with an acid such as maleic acid and maleic anhydride. The acrylic resin into which the carboxyl group has been introduced may be one containing a carboxyl group, and may be further introduced with another functional group such as a hydroxyl group. Examples of the acrylic resin introduced with a carboxyl group include WS-023 (manufactured by Nagase ChemteX Corporation), SG-700-AS (manufactured by Nagase ChemteX Corporation), and the like. Examples of the acrylic resin into which an epoxy group is introduced include SG-P3 (manufactured by Nagase ChemteX Corporation).

(B) Epoxy resin The epoxy resin can be used without particular limitation as long as it is an epoxy resin having two or more epoxy groups in one molecule. Examples of such epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, alicyclic epoxy resins, glycidyl ester type epoxy resins, and glycidyl amine type epoxy resins. Hydantoin type epoxy resin, isocyanurate type epoxy resin, acrylic acid-modified epoxy resin (epoxy acrylate), phosphorus-containing epoxy resin, and halides thereof (brominated epoxy resin etc.) and hydrogenated products. These epoxy resins may be used independently and may use 2 or more types together. Among these, novolak type epoxy resins such as phenol novolak type epoxy resin and cresol novolak type epoxy resin are preferable from the viewpoint of low hygroscopicity. Note that brominated epoxy resins and the like are particularly effective when flame resistance is required for the adhesive. Since acrylic acid-modified epoxy resin (epoxy acrylate) has photosensitivity, it is effective for imparting photocurability to the adhesive composition.

  An epoxy resin is mix | blended in the ratio of 12.5-50 mass parts with respect to 100 mass parts of acrylic resins. If the compounding amount of the epoxy resin with respect to 100 parts by mass of the acrylic resin is less than 12.5 parts by mass, the adhesive film 30 becomes too soft, and the flow of the adhesive film 30 cannot be sufficiently suppressed. On the other hand, when the compounding amount of the epoxy resin with respect to 100 parts by mass of the acrylic resin exceeds 50 parts by mass, the adhesive film 30 becomes too hard, and excellent soldering heat resistance cannot be imparted to the adhesive layer 6. In addition, since the compounding quantity of the epoxy resin with respect to 100 mass parts of acrylic resins does not show excessive adhesiveness in a semi-hardened state, and loses adhesiveness after hardening, it is preferable that it is 20-30 mass parts.

(C) 1st hardening | curing agent As a 1st hardening | curing agent, if it can be used for hardening of an epoxy resin and has a reaction start temperature higher than a 2nd hardening | curing agent, it can be especially used without a restriction | limiting. It is. Examples of such first curing agents include aliphatic amine curing agents, alicyclic amine curing agents, secondary or tertiary amine curing agents, aromatic amine curing agents, and acid anhydrides. Examples thereof include a curing agent, dicyandiamide, boron trifluoride amine complex salt, imidazole compound, phenol novolak resin having a triazine structure, and melamine resin. These may be used alone or in combination of two or more. However, the reaction start temperature of the first curing agent is preferably 80 ° C. or higher because the curing reaction is not caused in the step of reacting the second curing agent. However, since it is necessary to show sufficient reaction at the temperature of press cure, it is preferable that it is 100 degrees C or less.

  A 1st hardening | curing agent is mix | blended in the ratio of 0.05-0.5 mass part with respect to 100 mass parts of acrylic resins. When the blending amount of the first curing agent is less than 0.05 parts by mass, the flow of the adhesive film 30 during press curing cannot be sufficiently suppressed, and excellent solder heat resistance cannot be imparted to the adhesive layer 6. In addition, it is preferable that the compounding quantity of the 1st hardening | curing agent with respect to 100 mass parts of acrylic resins is 0.2-0.4 mass part from the reason of making the reaction at the time of press cure fully advance.

(D) 2nd hardening | curing agent A 2nd hardening | curing agent can be used without a restriction | limiting especially if it can be used for hardening of an epoxy resin and has a reaction start temperature lower than a 1st hardening | curing agent. is there. As such a 2nd hardening | curing agent, it is possible to use a polyamidoamine, an aliphatic polyamine, etc., for example. However, the reaction start temperature of the second curing agent is preferably 30 ° C. or less because the reaction can be sufficiently distinguished from the first curing agent. However, it is preferably 20 ° C. or higher for the reason that the pot life of the varnish is kept long or the storage stability of the varnish is increased.

A 2nd hardening | curing agent is mix | blended so that it may have the reactive group number of 20 to 70% of the reactive group number of an epoxy resin. Here, the ratio of the number of reactive groups of the second curing agent to the number of reactive groups of the epoxy resin can be calculated based on the epoxy equivalent and blending amount of the epoxy resin, and the active hydrogen equivalent and blending amount of the second curing agent. . For example, the epoxy equivalent of the epoxy resin is 190 (g / eq), the blending amount is 25 parts by mass, the active hydrogen equivalent of the second curing agent is 114 (g / eq), and the blending amount is 5 parts by mass. Then, the ratio of the reactive group number of the second curing agent to the reactive group number of the epoxy resin is calculated as follows.
100 × [(1/114) × 5] / [(1/190) × 25] = 33%

  When the number of reactive groups of the second curing agent is less than 20% of the number of reactive groups of the epoxy resin, the adhesive film 30 becomes too soft, and the flow of the adhesive film 30 cannot be sufficiently suppressed. On the other hand, when the number of reactive groups of the second curing agent exceeds 70% of the number of reactive groups of the epoxy resin, the adhesive film 30 becomes too hard, and excellent soldering heat resistance cannot be imparted to the adhesive layer 6. In addition, the ratio of the reactive group number of the second curing agent to the reactive group number of the epoxy resin may be 20 to 40% of the reactive group number of the epoxy resin because the reaction state of the epoxy resin is maintained in an appropriate semi-cured state. preferable.

  The adhesive composition of this invention may contain an additive etc. as needed. Examples of the additive include fillers such as silica, mica, clay, talc, titanium oxide, calcium carbonate, and aluminum hydroxide, and dispersants such as a silane coupling agent.

  The present invention is not limited to the above embodiment. For example, in the said embodiment, although only the adhesive film 30 is manufactured using the adhesive composition which has said (A)-(D), the adhesive bond layer 14 of the coverlay 10, the metal-clad laminate 20 The adhesive layer 22 may also be manufactured using the adhesive composition having the above (A) to (D).

  Moreover, in the said manufacturing method, although the reinforcement board 7, the adhesive film 30, the metal-clad laminated board 20, and the coverlay 10 are piled up, the adhesive bond layers 14 and 22 and the adhesive film 30 are hardened collectively, flexible In order to obtain the printed circuit board 100, the adhesive layers 14 and 22 and the adhesive film 30 do not necessarily have to be cured at once. For example, the reinforcing plate 7, the adhesive film 30 and the metal-clad laminate 20 are overlaid, the adhesive layer 22 and the adhesive film 30 are cured to obtain a laminated body, and then the laminated body and the coverlay 10 are overlaid. In addition, the flexible printed wiring board 100 can be obtained even if the adhesive layer 14 is cured.

  Hereinafter, although the content of the present invention will be described more specifically with reference to examples and comparative examples, the present invention is not limited to the following examples. In Tables 1 to 3, unless otherwise specified, numerical units represent parts by mass.

(Examples 1-4 and Comparative Examples 1-7)
First, (A) acrylic resin, (B) epoxy resin, (C) first curing agent, (D) second curing agent, (E) filler, and (F) dispersant are blended in the proportions shown in Tables 1 to 3. Thus, an adhesive composition was obtained. Then, the adhesive composition is dissolved in a solvent composed of methyl ethyl ketone, heated and stirred at the “reaction temperature of the adhesive composition” shown in Tables 1 to 3 for 8 hours, and the second curing agent and the epoxy resin are mixed. It was made to react and the adhesive solution containing an adhesive agent was obtained.

  The obtained adhesive solution was applied to the surface of a PET film which was subjected to a release treatment with a non-silicon material, and heated at 120 ° C. for 4 minutes to form an adhesive film. At this time, the thickness of the adhesive film was set to 25 μm.

Specific examples of the (A) acrylic resin, (B) epoxy resin, (C) first curing agent, (D) second curing agent, (E) filler, and (F) dispersant are as follows. used.
(A) Acrylic resin (A-1) Ethyl acrylate-butyl acrylate-acetonitrile copolymer having a carboxyl group introduced (WS-023 manufactured by Nagase ChemteX Corporation)
(A-2) Ethyl acrylate-butyl acrylate-acetonitrile copolymer having a carboxyl group introduced (SG-700-AS manufactured by Nagase ChemteX Corporation)
(B) Epoxy resin bisphenol A type epoxy resin (JER828EL manufactured by JER)
Phenol novolac type epoxy resin (JER152 manufactured by JER)
(C) a first curing agent (C-1) 3 boron trifluoride (manufactured by Wako Pure Chemical Industries, Ltd. _BF 3-MEA)
Reaction start temperature: 80 ° C
(C-2) Imidazole (C11Z-CN manufactured by Shikoku Chemicals)
Reaction start temperature: 130 ° C
(D) Second curing agent (D-1) Polyamidoamine (DIC-EA-2020)
Reaction start temperature: 20 ° C
Active hydrogen equivalent (g / eq): 114
(D-2) Polyamidoamine (HR-11 manufactured by Fuji Kasei)
Reaction start temperature: 20 ° C
Active hydrogen equivalent (g / eq): 110
(D-3) Phenol resin (PSM-4326 manufactured by Gunei Chemical Co., Ltd.)
Reaction start temperature: 120 ° C
Active hydrogen equivalent (g / eq): 120
(E) Filler aluminum hydroxide (H-43S manufactured by Showa Denko KK)
(F) Dispersant unsaturated fatty acid polyamine amide and acidic ester (BYK-980 manufactured by Big Chemie Japan)

[Characteristic evaluation]
The adhesive film was roll-laminated on the CCL base surface (surface opposite to the circuit), and then the PET film was peeled off. Then, a polyimide (PI) plate or a mirror-finished stainless steel (SUS) plate is placed on the adhesive film, press cured at a pressure of 55 kgf / cm ² for 1 hour at 160 ° C., and the PI plate or SUS plate is applied to the CCL. Were bonded to obtain a sample for characteristic evaluation. And the following characteristics were evaluated about this sample.

(Adhesive layer flow-out)
About the sample which adhered the PI board to CCL among the said samples, the maximum value of the flow-out amount of the adhesive film from the edge part was measured visually. The results are shown in Tables 1-3. In addition, if the flow-out amount of the adhesive is 60 μm or less, the flow-out of the adhesive is sufficiently “accepted”, and if it exceeds 60 μm, the flow-out of the adhesive is not sufficiently suppressed. “Fail”.

(Solder heat resistance after moisture absorption)
The sample obtained as described above was placed in a constant temperature bath at 40 ° C. and 90% RH for 96 hours, then floated in a solder bath melted at 260 ° C. for 3 minutes, and the presence or absence of swelling was observed. Samples that do not swell for more than 3 minutes are indicated as “A” as being excellent in solder heat resistance, and samples that are swelled in less than 3 minutes for more than 10 seconds are indicated as “B” as being inferior in solder heat resistance. It was decided to. Samples that were swollen in 10 seconds or less were labeled “C” as being inferior in solder heat resistance. The results are shown in Tables 1-3.

(Peel strength)
The 90 ° peel strength was measured for the sample obtained as described above. The results are shown in Tables 1-3. In Tables 1 to 3, samples having a peel strength of 10 N / cm or more are particularly excellent in adhesion.

  From the results shown in Tables 1 to 3, it was found that the adhesive compositions of Examples 1 to 4 reached the acceptance criteria for the flowability of the adhesive film during press curing and the solder heat resistance after moisture absorption. On the other hand, it was found that the adhesive compositions of Comparative Examples 1 to 7 did not reach the acceptance criteria for at least one of the flowability of the adhesive film during press curing and the solder heat resistance after moisture absorption.

  From the above, it was confirmed that according to the adhesive composition of the present invention, it is possible to realize an adhesive film that exhibits excellent solder heat resistance and can also suppress flow out during press curing.

  30 ... Adhesive film

Claims (3)

(A) an acrylic resin;
(B) an epoxy resin;
(C) a first curing agent;
(D) a second curing agent,
The second curing agent (D) has a lower reaction initiation temperature than the first curing agent (C);
The said epoxy resin (B) is mix | blended in the ratio of 12.5-50 mass parts with respect to 100 mass parts of said acrylic resins (A),
Said 1st hardening | curing agent (C) is mix | blended in the ratio of 0.05-0.5 mass part with respect to 100 mass parts of said acrylic resins (A),
The second curing agent (D) is blended so as to have a reactive group number of 20 to 70% of the reactive group number of the epoxy resin (B),
An adhesive composition characterized by the above. The adhesive composition according to claim 1 is disposed at a temperature equal to or higher than a reaction start temperature of the second curing agent (D) and lower than a reaction start temperature of the first curing agent (C). Forming an adhesive; and
Applying the adhesive solution containing the adhesive on the substrate and drying it to form an adhesive film.   The adhesive film obtained by the manufacturing method of the adhesive film of Claim 2.

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