WO2019193880A1 - Adhesive composition, connection structure, and manufacturing method of connection structure - Google Patents

Abstract

[Problem] To provide an adhesive composition with high adhesion reliability, a connection structure, and a manufacturing method of the connection structure. [Solution] This adhesive composition contains a film forming resin, an acrylate-base compound, a polymerization initiator, and a carbodiimide-base compound, wherein at least one of the film forming resin and acrylate-base compound is a compound having a carboxy group, and the content of the carbodiimide-base compound is 0.1-150 mass% of the total mass of the compounds having a carboxy group.

Description

Adhesive composition, connection structure, and method for manufacturing connection structure

The present invention relates to an adhesive composition, a connection structure, and a method for manufacturing the connection structure.

In recent years, either an adhesive using a polymerization reaction by an epoxy compound or an adhesive using a polymerization reaction by an acrylate compound is generally used for bonding an electronic component and a wiring board. Is common. For example, Patent Document 1 below discloses a film-like adhesive for electronic parts mainly composed of an epoxy compound.

On the other hand, acrylate compounds show higher reactivity even at low temperatures than epoxy compounds. Therefore, an adhesive containing an acrylate compound can be used, for example, when bonding an electronic component that does not want to be heated.

JP 2005-264109 A

However, the adhesive containing an acrylate compound was more likely to deteriorate in a reliability test in a humid heat environment than an epoxy compound. Therefore, it has been required to further improve the adhesion reliability in the adhesive containing the acrylate compound.

Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a new and improved adhesive composition and connection structure having higher adhesion reliability. There is.

In order to solve the above-described problems, according to one aspect of the present invention, a film-forming resin, an acrylate-based compound, a polymerization initiator, and a carbodiimide-based compound are contained, and the film-forming resin or the acrylate-based compound is included. Is a compound having a carboxy group, and the content of the carbodiimide compound is 0.1% by mass or more and 150% by mass or less based on the total mass of the compound having a carboxy group. An adhesive composition is provided.

The content of the carbodiimide compound may be 30% by mass or less based on the total mass of the compound having a carboxy group.

The content of the carbodiimide compound may be 5% by mass or more based on the total mass of the compound having a carboxy group.

The film forming resin may be a polyester resin or a polyurethane resin.

The acid value of the film forming resin may be 1 KOHmg / g or more.

The acrylate compound may be a (meth) acrylate resin.

The polymerization initiator may be a radical polymerization initiator.

The adhesive composition may be provided in the form of a film.

The adhesive composition may further include conductive particles.

Moreover, in order to solve the said subject, according to another viewpoint of this invention, said 1st electronic component and 2nd electronic component which were adhere | attached via said adhesive composition with said adhesive composition A connection structure is provided.

In order to solve the above problem, according to another aspect of the present invention, the adhesive composition is provided between a first electronic component and a second electronic component, and the first electronic component is provided. A method for manufacturing a connection structure is provided in which the first electronic component and the second electronic component are connected by applying pressure from the component or the second electronic component.

In order to solve the above problems, according to another aspect of the present invention, the adhesive composition further including conductive particles, the first electronic component bonded via the adhesive composition, and A connection structure provided with a second electronic component, wherein the terminal included in the first electronic component and the terminal included in the second electronic component are conductively connected by sandwiching the conductive particles. Is done.

Furthermore, in order to solve the above problems, according to another aspect of the present invention, the adhesive composition further including conductive particles is provided between the first electronic component and the second electronic component, A method for manufacturing a connection structure is provided in which the first electronic component and the second electronic component are conductively connected by applying pressure from the first electronic component or the second electronic component.

With the above configuration, it is possible to promote intermolecular crosslinking within the adhesive composition by reacting the carboxy group of the film-forming resin or acrylate compound with the carbodiimide compound.

As described above, according to the present invention, an adhesive composition and a connection structure having higher adhesion reliability can be provided.

It is a schematic diagram explaining the 1st application example of the adhesive composition which concerns on one Embodiment of this invention. It is a mimetic diagram explaining adhesion by the 1st example of application of an adhesive constituent concerning the embodiment. It is a schematic diagram explaining the 2nd application example of the adhesive composition which concerns on the same embodiment. It is a mimetic diagram explaining adhesion by the 2nd application example of an adhesive constituent concerning the embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

<1. Configuration of Adhesive Composition>
First, the structure of the adhesive composition which concerns on one Embodiment of this invention is demonstrated. The adhesive composition according to the present embodiment includes a film-forming resin, an acrylate compound, a polymerization initiator, and a carbodiimide compound.

In this embodiment, at least one of the film-forming resin or the acrylate compound has a carboxy group. The carboxy group which these compounds have can react with a carbodiimide type compound, and can form many intermolecular bridge | crosslinks inside an adhesive composition. Thereby, the adhesive composition which concerns on this embodiment can implement | achieve higher adhesion reliability.

The film-forming resin imparts film forming properties to the adhesive composition. Thereby, film formation resin can improve the applicability | paintability or film formation property of adhesive composition, and can raise the cohesion force in the whole adhesive composition. Specifically, the film-forming resin may be an organic resin having an average molecular weight of 10,000 or more. The film-forming resin is preferably an organic resin having an average molecular weight of 10,000 or more and 80000 or more from the viewpoint of improving applicability or film-forming property.

For example, the film-forming resin may be a phenoxy resin, a polyester resin, a polyurethane resin, a polyester urethane resin, an acrylic resin, a polyimide resin, a butyral resin, or the like alone or in combination of two or more. The content of the film-forming resin may be, for example, 40% by mass to 90% by mass, and preferably 50% by mass to 80% by mass with respect to the total mass of the adhesive composition. .

As described above, the film-forming resin can have a carboxy group. Examples of such a film-forming resin include polyester resins, polyurethane resins or polyester urethane resins having an ester bond or urethane bond containing a carboxy group in the main chain, and acrylic resins having a carboxy group in the side chain. The film-forming resin may further have a phenolic hydroxy group, an epoxy group, an amino group, or a hydroxy group in order to further increase the reactivity with the carbodiimide compound.

In the present embodiment, the film-forming resin is preferably a polyurethane resin, and more preferably a polyester urethane resin, in order to ensure reactivity with a carbodiimide compound described later. Since the polyurethane resin or the polyester urethane resin has a carboxy group in the urethane bond or ester bond of the main chain, it is possible to form a stronger intermolecular crosslink by reaction with a carbodiimide compound.

In particular, since the polyester urethane resin has low fluidity, sufficient adhesion strength can be secured even when the adherends are pressed at a low pressure during bonding. In such a case, the adhesive composition can suppress the occurrence of warpage due to adhesion in an adherend such as a thin glass substrate or plastic substrate.

Here, the acid value of the film-forming resin is preferably 1 KOH mg / g or more, and more preferably 5 KOH mg / g or more. The acid value represents the number of mg of potassium hydroxide necessary to neutralize free fatty acids present in 1 g of a polymer compound such as resin or oil, and represents the amount of carboxylic acid contained in the polymer compound. It becomes. That is, it can be said that the film-forming resin has more carboxy groups as the acid value is higher. When the acid value of the film-forming resin is 1 KOHmg / g or more, since the film-forming resin contains many carboxy groups that can react with the carbodiimide-based compound and can become a crosslinking point, the adhesive composition has more adhesive reliability. Can be improved.

However, if the acid value of the film-forming resin is excessively high, the liberated carboxylic acid may corrode the metal part or the like of the adherend (also referred to as migration). Accordingly, the acid value of the film-forming resin is preferably 50 KOH mg / g or less. In particular, when an adhesive composition is used for an anisotropic adhesive that connects metal terminals to each other in an anisotropic conductive manner, in order to suppress corrosion of the metal terminals to be connected, the acid value of the film-forming resin is as described above. It is preferable not to exceed the upper limit. In addition, when the acid value of film forming resin is high, it is also possible to suppress corrosion of the connected metal terminal by adding an antioxidant to the adhesive composition. The acid value of the film-forming resin is measured based on, for example, the Japanese Industrial Standard “JIS K 0070-1992: Acid, Saponification, Ester, Iodine, Hydroxyl, and Unsaponifiable Test Methods for Chemical Products”. be able to.

The acrylate compound imparts adhesiveness to the adhesive composition. Specifically, the acrylate-based compound is bonded at the time of bonding, thereby bonding the objects to be bonded together. For example, the acrylate compound may be a (meth) acrylate resin having radical polymerizability. In addition, (meth) acrylate represents containing both acrylic acid ester (namely, acrylate) and methacrylic acid ester (namely, methacrylate). (Meth) acrylate resins are highly reactive even at low temperatures. Therefore, the adhesive composition can reliably adhere objects to be bonded even when the heating temperature at the time of bonding is low. According to this, even if it is a to-be-adhered object which may receive damage with a heat | fever, an adhesive composition can be adhere | attached without a problem. The content of the acrylate compound may be, for example, 5% by mass to 40% by mass, and preferably 10% by mass to 30% by mass with respect to the total mass of the adhesive composition. .

The acrylate compound may be, for example, a monofunctional or polyfunctional monomer or oligomer containing an acrylate residue or a methacrylate residue in the molecule.

As the monofunctional (meth) acrylate monomer, an alkyl (meth) acrylate having a linear or branched alkyl group can be exemplified. For example, as alkyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, sec-butyl (meth) Acrylate, tert-butyl (meth) acrylate, isobutyl (meth) acrylate, n-pentyl (meth) acrylate, isopentyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl acrylate, n-heptyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate Rate, isodecyl (meth) acrylate, n-dodecyl (meth) acrylate, isomyristyl (meth) acrylate, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate, n-stearyl (meth) acrylate, isostearyl ( Examples include meth) acrylate, n-lauryl (meth) acrylate, and the like.

Examples of the polyfunctional (meth) acrylate include tricyclodecane dimethanol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, and neopentanediol. Di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di ( Bifunctional (meth) acrylates such as (meth) acrylate, tripropylene glycol di (meth) acrylate or polypropylene glycol di (meth) acrylate, or trimethylolpropane tri (meth) acrylate, pentaerythritol Tri (meth) acrylate, tris (acryloyloxyethyl) isocyanurate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate or dipentaerythritol hexa (meth) Trifunctional or higher functional (meth) acrylates such as acrylates can be listed.

As described above, the acrylate compound may have a carboxy group. When the acrylate compound has a carboxy group, the carbodiimide compound promotes intermolecular crosslinking of the carboxy group, and thus the adhesive composition can further improve the adhesion reliability. In order to further increase the reactivity with the carbodiimide compound, the acrylate compound may further have a phenolic hydroxy group, an epoxy group, an amino group, or a hydroxy group.

The polymerization initiator is a compound that initiates polymerization of the acrylate compound. Specifically, the polymerization initiator may be a radical polymerization initiator that generates radicals by external stimulation (light, heat, pressure, or the like). The polymerization initiator may be a known radical polymerization initiator, for example, a peroxide radical initiator. Examples of the polymerization initiator include diacyl peroxides such as benzoyl peroxide, alkyl peresters such as t-hexyl peroxypivalate and t-butyl peroxybenzoate, and 1,1-di (t-butylperoxy). Peroxyketals such as cyclohexane may be used alone or in combination of two or more. The content of the polymerization initiator may be, for example, 1% by mass to 50% by mass, and preferably 5% by mass to 30% by mass with respect to the total mass of the adhesive composition. .

The carbodiimide compound is a compound containing a functional group represented by a chemical formula (—N═C═N—). The functional group represented by the chemical formula (—N═C═N—) has a large polarization within the functional group. Therefore, it is expected that the carbodiimide-based compound has the following effects by being included in the adhesive composition.

For example, carbodiimide compounds are expected to improve the adhesive strength of the adhesive composition by electrostatic interaction with the polar surface of the adherend. In addition, carbodiimide compounds are expected to suppress hydrolysis of the film-forming resin and prevent corrosion of the surface of the adherend by capturing free ions such as hydrogen ions or hydroxide ions. Is done. Further, when a carbodiimide compound that functions as an acid scavenger is added to the adhesive composition, an inorganic compound such as a metal oxide or hydrotalcite may not be added to the adhesive composition. According to this, when the adhesive composition is used as an anisotropic adhesive, it is possible to suppress occurrence of a short circuit between the connection terminals due to an inorganic compound such as a metal oxide or hydrotalcite. it can.

In particular, when the film-forming resin is a polyurethane resin or a polyester urethane resin, the urethane bond or ester bond contained in the main chain of the film-forming resin is easily hydrolyzed using an acid as a catalyst. Therefore, the hydrolysis reaction in a polyurethane resin or a polyester urethane resin can be effectively suppressed by including in the adhesive composition a carbodiimide compound that functions as an acid scavenger. Moreover, the carbodiimide-type compound can improve the adhesive strength of adhesive composition by reacting with the carboxy group which a polyurethane resin or a polyester urethane resin has, and promoting intermolecular crosslinking.

In addition, the intermolecular crosslinking reaction promoted by the above-described carbodiimide compound does not occur at the time of adhesion of the adherend, but occurs in a high temperature and high humidity environment after adhesion. Therefore, since the adhesive composition can maintain or improve the adhesive strength even after a long period of time, higher adhesive reliability can be realized. That is, since the adhesive composition can maintain sufficient adhesion reliability even in a harsh environment such as high temperature and high humidity, it can have high weather resistance.

Note that the above-described effects can occur when the carbodiimide compound includes a functional group represented by the chemical formula (—N═C═N—). Therefore, the carbodiimide compound described in this specification has a functional group represented by a chemical formula (—N═C═N—) such as a modified body, a reaction product, or a derivative starting from carbodiimide as a molecule. Does not contain compounds that do not have it inside.

When the functional group represented by the chemical formula (-N = C = N-) is extremely small in the molecule, for example, the functional group represented by the chemical formula (-N = C = N-) is inevitably mixed. In this case, the functional group represented by the chemical formula (—N═C═N—) may not be included.

Such carbodiimide compounds may be monomers, oligomers or polymers. For example, as the carbodiimide compound, polyvalent carbodiimide (for example, polycarbodiimide) or carbodiimide-modified isocyanate can be preferably used. The carbodiimide compound is preferably a polymer having a relatively large molecular weight.

The carbodiimide compound is contained in the adhesive composition in an amount of 0.1% by mass or more and 150% by mass or less based on the total mass of the film-forming resin or acrylate compound having a carboxy group. When content of a carbodiimide type compound is less than 0.1 mass% with respect to the total mass of the compound which has a carboxy group, the effect which improves the adhesive reliability of adhesive composition is not acquired. Therefore, the lower limit of the content of the carbodiimide compound is 0.1% by mass, preferably 5% by mass with respect to the total mass of the compound having a carboxy group. On the other hand, when the content of the carbodiimide compound is more than 150% by mass with respect to the total mass of the compound having a carboxy group, it becomes difficult to uniformly disperse the carbodiimide compound in the adhesive composition. Therefore, the upper limit of the content of the carbodiimide-based compound is 150% by mass, preferably 30% by mass, based on the total mass of the compound having a carboxy group.

As described above, the adhesive composition according to this embodiment can improve the adhesion reliability by including a carbodiimide compound. Moreover, when the adhesive composition according to the present embodiment is used as an anisotropic adhesive, it can further improve the corrosion resistance of the adherend and the reliability of the conductive connection.

In addition, the adhesive composition may further include additives such as a silane coupling agent, an inorganic filler, a colorant, or an antioxidant, as necessary, in addition to the above-described compounds. Furthermore, the adhesive composition may contain a general compound described in JP2010-232191A or JP2010-242101 in addition to or in place of the above-described compounds.

<2. Application example of adhesive composition>
(2.1. First application example)
Next, with reference to FIG.1 and FIG.2, the 1st application example of the adhesive composition which concerns on this embodiment is demonstrated. FIG. 1 is a schematic diagram illustrating a first application example of the adhesive composition, and FIG. 2 is a schematic diagram illustrating adhesion according to the first application example of the adhesive composition.

As shown in FIG. 1, the first application example of the adhesive composition is an adhesive film 11 in which an adhesive layer 100 including an adhesive composition 101 is formed on a base film 110. The adhesive film 11 includes a base film 110 and an adhesive layer 100, and is stored, for example, in a roll form wound around a reel member or the like.

The base film 110 is a resin film that supports the adhesive layer 100, and is composed of, for example, polyethylene terephthalate (PET). The adhesive layer 100 is a layer including the adhesive composition 101 according to the present embodiment, and is provided on one surface of the base film 110 in a film shape.

In the first application example, as shown in FIG. 2, the adhesive layer 100 including the adhesive composition 101 is peeled off from the base film 110 and attached to the adherends 20 and 30, and heated and pressed. The adherends 20 and 30 are bonded. The adherends 20 and 30 are, for example, various substrates such as a glass substrate, a rigid substrate, a plastic substrate or a ceramic substrate, a semiconductor element such as an FPC (Flexible Printed Circuit) or an IC (Integrated Circuit) chip, or a TAB (Tape Automated Bonding). It may be an electronic component such as a tape or a functional module.

According to the first application example of the adhesive composition, it is possible to perform highly reliable bonding between objects to be bonded. As another example of use, the adhesive composition may be used to fill a space provided in the structure.

(2.2. Second application example)
Subsequently, a second application example of the adhesive composition according to this embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a schematic diagram for explaining a second application example of the adhesive composition, and FIG. 4 is a schematic diagram for explaining adhesion by the second application example of the adhesive composition.

As shown in FIG. 3, the second application example of the adhesive composition is an anisotropic conductive connection film 12 in which an adhesive layer 100 including an adhesive composition 101 and conductive particles 102 is formed on a base film 110. It is. The anisotropic conductive connection film 12 includes a base film 110 and an adhesive layer 100 and is stored, for example, in a roll form wound around a reel member or the like. Note that the description of the second application example includes a state in which the adhesive composition 101 does not include the conductive particles 102 or a state in which the adhesive composition 101 is not formed as the adhesive layer 100. It is not excluded from.

The base film 110 is a resin film that supports the adhesive layer 100, and is composed of, for example, polyethylene terephthalate (PET). The adhesive layer 100 is a layer including the adhesive composition 101 and the conductive particles 102 according to the present embodiment, and is provided in a film shape on one surface of the base film 110.

The conductive particles 102 may be particles made of a metal such as nickel, iron, copper, aluminum, tin, lead, chromium, cobalt, silver, or gold, or particles made of a metal alloy thereof. Alternatively, the conductive particles 102 may be particles obtained by coating the surfaces of the resin particles with the metal or alloy described above. Furthermore, the conductive particles 102 may be particles in which the surface of the metal particles, alloy particles, or metal-coated particles described above is coated with an insulating thin film. The average particle diameter of the conductive particles 102 may be, for example, 1 μm or more and 30 μm or less, and preferably 2 μm or more and 10 μm or less, from the viewpoint of ensuring conduction reliability between the adherends. The content of the conductive particles 102 may be, for example, 2% by mass or more and 50% by mass or less with respect to the total mass of the adhesive layer 100, from the viewpoint of securing conduction reliability and insulation reliability between objects to be bonded. Preferably, it may be 3% by mass or more and 20% by mass or less.

In the second application example, as shown in FIG. 4, the adhesive layer 100 including the adhesive composition 101 and the conductive particles 102 is peeled off from the base film 110 and provided with terminals 210 and 310 on the adhesive surface. Affixed to the adhesives 20 and 30. The terminals 210 and 310 are connected to circuits formed on the adherends 20 and 30, respectively. Here, the adhesive layer 100 is heated and pressed to adhere the adherends 20 and 30, and the conductive particles 102 are sandwiched between terminals 210 and 310 provided on the adhesion surfaces of the adherends 20 and 30. Thus, the terminals 210 and 310 are electrically connected to each other.

The adherends 20 and 30 are, for example, various circuit boards such as a glass substrate, a rigid substrate, a plastic substrate, or a ceramic substrate, a semiconductor element such as an FPC (Flexible Printed Circuit) or an IC chip, a TAB (Tape Automated Bonding) tape or a function. It may be an electronic component such as a sex module.

According to the second application example of the adhesive composition, it is possible to perform highly reliable adhesion between adherends and to electrically connect circuits formed on the adherends.

Hereinafter, the manufacturing method of the adhesive composition and the connection structure according to the present embodiment will be described in more detail with reference to examples. In addition, the Example shown below is an example for showing the feasibility and the effect of the manufacturing method of the adhesive composition and the connection structure according to the present embodiment, and the present invention is limited to the following example. It is not a thing.

(Manufacture of adhesive composition)
The materials shown in Table 1 below were mixed to prepare an adhesive composition. Thereafter, conductive particles (average particle diameter 4 μm, AUL 704 manufactured by Sekisui Chemical Co., Ltd.) were dispersed in the adjusted adhesive composition. The adhesive composition in which the conductive particles were dispersed was applied to a PET film and dried so that the average film thickness of the adhesive composition after drying was 10 μm. Thereby, the adhesive composition and adhesive film which function as an anisotropic adhesive agent and an anisotropic conductive film were manufactured. For example, when the average film thickness of the adhesive composition after drying is 10 μm, the conductive particles may be blended in the adhesive composition so that the number density is 8000 / mm ² . The number density of the conductive particles can be obtained by observing the number density of 10 conductive particles at 10 points in a 200 μm × 200 μm square arbitrarily extracted with a metal microscope and calculating an average value.

In Table 1, “UR8200” (manufactured by Toyobo Co., Ltd.), “UR1700” (manufactured by Toyobo Co., Ltd.), and “UR3500” (manufactured by Toyobo Co., Ltd.) correspond to a film-forming resin having a carboxy group. The acid value of “UR8200” is less than 0.5 KOHmg / g, the acid value of “UR1700” is 26 KOHmg / g, and the acid value of “UR3500” is 35 KOHmg / g. In addition, “EB-600” (manufactured by Daicel Cytec Co., Ltd.) corresponds to an acrylate compound having no carboxy group, and “Perhexa C” (manufactured by NOF Corporation) corresponds to a polymerization initiator. ) P ”(manufactured by Rhein Chemie) corresponds to a carbodiimide compound, and“ KBM-503 ”(manufactured by Shin-Etsu Chemical Co., Ltd.) corresponds to a silane coupling agent.

In addition, the unit of the ratio shown in Table 1 is “part by mass”. Furthermore, in Table 1, the mass ratio of the carbodiimide-type compound (Stabaxol P) with respect to resin ("UR8200", "UR1700", and "UR3500") containing a carboxy group was also shown.

(Manufacture of connection structure)
Then, the connection structure was manufactured using the adhesive composition manufactured above. Specifically, first, an FPC (Flexible Printed Circuit) (thickness: 38 μm) formed of 8 μm-thick Cu and plated with Sn is arranged at a pitch of 50 μm, and indium tin oxide (ITO) over the entire surface. ) Coated glass substrate (thickness 0.7 mm).

The adhesive composition produced above was cut into a 1.5 mm wide slit and attached to the ITO coated glass substrate. Then, FPC was mounted on the adhesive composition so that the ITO coated glass substrate and the terminal face each other, and temporarily fixed. Subsequently, using a Teflon (registered trademark) material having a thickness of 100 μm as a buffer material, the temporarily fixed ITO coated glass substrate, the adhesive composition, and the FPC were subjected to main pressure bonding with a pressure bonding tool having a width of 1.5 mm. Thereby, the connection structure was manufactured. The conditions for the main pressure bonding were 180 ° C. and 3.5 MPa for 6 seconds, and the temperature of the pressure bonding stage was 40 ° C.

(Evaluation methods)
About the connection structure manufactured above, conduction resistance, adhesive strength, and indentation reliability were evaluated. The conduction resistance and the adhesive strength were evaluated at the initial stage and after the reliability test, respectively. The reliability test was performed by using the temperature 85 ° C./humidity 85% RH as environmental test conditions and leaving the connection structure for 500 hours under the above-described high temperature and high humidity. For the reliability test, an environmental testing machine (a constant temperature and humidity chamber, PR series manufactured by Espec) was used.

The conduction resistance was measured using a digital multimeter (Yokogawa Digital Multimeter 7555). Specifically, the connection resistance measured when a current of 1 mA was passed by the four-terminal method was defined as a conduction resistance. Specifically, the case where the conduction resistance was less than 2Ω was evaluated as A (very preferable), the case where the resistance was 2Ω or more and 4Ω or less was B (no problem), and the case where the conduction resistance was more than 4Ω was evaluated as C (NG).

The adhesive strength was measured using a tensile tester (AMC RTC1201). Specifically, the bonded FPC was pulled up at an angle of 90 ° with respect to the ITO-coated glass substrate at a speed of 50 mm / second, and the tensile strength measured when the FPC peeled was defined as the adhesive strength. Specifically, those having an adhesive strength of more than 8 N / cm are A (very preferable), those having 5 N / cm or more and 8 N / cm or less are B (no problem), and those having an adhesion strength of less than 5 N / cm are C ( NG).

Indentation reliability was evaluated by observing the connection structure using a differential interference microscope (MX51 manufactured by Olympus Corporation). Specifically, based on the indentation observed in the connection structure according to Comparative Example 1, A is a case where the indentation is observed more clearly, B is a case where the indentation is observed equally, and the indentation is clear. The case where it was not observed was evaluated as C. In addition, A shows that evaluation is better than C.

The comprehensive judgment was evaluated by comprehensively judging the initial evaluation results of the conduction resistance and the adhesive strength, the evaluation results after the reliability test, and the indentation reliability. A shows that evaluation is better than C. In addition, it is preferable that the evaluation is B or more in practical use of the connection structure.

The above results are shown in Table 2 below. In Comparative Examples 2 and 4, since the adhesive composition could not be formed into a film, conduction resistance and adhesive strength were not evaluated.

Referring to the results in Table 2, the connection structures according to Examples 1 to 9 do not have a large increase in the conduction resistance after the reliability test and have a large adhesive strength as compared with Comparative Examples 1 to 4. It turns out that it has not fallen.

Further, it can be seen that Examples 7 to 9, in which the acid value of the film-forming resin having a carboxy group is higher, have a higher evaluation of the adhesive strength after the reliability test than Examples 1 to 6. Therefore, it can be seen that Examples 7 to 9 have higher weather resistance than Examples 1 to 6.

From the above results, it can be seen that the adhesive composition according to the present embodiment has high adhesion reliability because it can maintain high adhesion strength even after the reliability test.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 11 Adhesive film 12 Anisotropic conductive connection film 20, 30 Bonded object 100 Adhesive layer 101 Adhesive composition 102 Conductive particle 110 Base film 210, 310 Terminal

Claims (13)

A film-forming resin;
An acrylate compound;
A polymerization initiator;
A carbodiimide compound,
Containing
At least one or more of the film-forming resin or the acrylate compound is a compound having a carboxy group,
Content of the said carbodiimide type compound is an adhesive composition which is 0.1 to 150 mass% with respect to the total mass of the compound which has the said carboxy group. The adhesive composition according to claim 1, wherein a content of the carbodiimide compound is 30% by mass or less based on a total mass of the compound having a carboxy group. The adhesive composition according to claim 1 or 2, wherein the content of the carbodiimide compound is 5% by mass or more based on the total mass of the compound having a carboxy group. The adhesive composition according to any one of claims 1 to 3, wherein the film-forming resin is a polyester resin or a polyurethane resin. The adhesive composition according to claim 4, wherein the acid value of the film-forming resin is 1 KOHmg / g or more. The adhesive composition according to any one of claims 1 to 5, wherein the acrylate compound is a (meth) acrylate resin. The adhesive composition according to any one of claims 1 to 6, wherein the polymerization initiator is a radical polymerization initiator. The adhesive composition according to any one of claims 1 to 7, wherein the adhesive composition is provided in a film form. The adhesive composition according to any one of claims 1 to 8, wherein the adhesive composition further includes conductive particles. An adhesive composition according to any one of claims 1 to 8;
A first electronic component and a second electronic component bonded via the adhesive composition;
A connection structure comprising: An adhesive composition according to any one of claims 1 to 8 is provided between a first electronic component and a second electronic component, and the first electronic component or the second electronic component A method for manufacturing a connection structure, wherein the first electronic component and the second electronic component are connected by applying pressure from the side. An adhesive composition according to claim 9;
A first electronic component and a second electronic component bonded via the adhesive composition;
With
A connection structure in which a terminal included in the first electronic component and a terminal included in the second electronic component are conductively connected by sandwiching the conductive particles. By providing the adhesive composition according to claim 9 between the first electronic component and the second electronic component, and pressurizing from the first electronic component or the second electronic component side, A method for manufacturing a connection structure, wherein the first electronic component and the second electronic component are conductively connected.

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