TW201313858A - Anistropic conductive member - Google Patents

Abstract

Provided is an anistropic conductive member capable of suppressing the deterioration of an epoxy resin and reducing connection resistance. Conductive particles are dispersed in an insulating adhesive resin containing an epoxy resin, a cationic polymerization initiator, and core-shell polymer particles having a glycidyl group in the shell section. As a result, it is possible to improve the affinity of the epoxy resin with the shell section, minimize the deterioration of the epoxy resin, and reduce connection resistance.

Description

Anisotropic conductive material

The present invention relates to an anisotropic conductive material in which conductive particles are dispersed. The present application claims priority on the basis of Japanese Patent Application No. 2011-129294, filed on Jan.

Conventionally, when a liquid crystal panel, a tape reel package (TCP) substrate, a liquid crystal panel and a die-bonded (COF) substrate, a printed wiring board (PWB), a TCP substrate, a PWB, and a COF substrate are connected, an anisotropic direction is used. Conductive film (ACF).

The anisotropic conductive film is formed by forming a resin composition containing an epoxy resin, a polymerization initiator, or conductive particles into a film shape, and can be classified into an anionic polymerization type, a cationic polymerization type, or the like according to a polymerization method for an epoxy resin. .

One of the methods for adding the rubber-like polymer particles, that is, the so-called core-shell polymer particles, to the anisotropic conductive film is known as a method for improving the adhesion strength of the anisotropic conductive film (see, for example, Patent Documents 1 and 2). By adding the core-shell polymer particles, a cured product having high toughness can be obtained, and a cured product excellent in heat resistance and insulation properties can be obtained.

Patent Document 1: Japanese Laid-Open Patent Publication No. 2008-195852

Patent Document 2: Japanese Laid-Open Patent Publication No. 2010-001346

The mechanism of hardening caused by cationic polymerization is inferred as follows: a cationic species or a Lewis acid generated from an initiator due to external stimuli such as heat or light to give an epoxy group The ring is opened and polymerized without interruption by a chain reaction to form a network structure. Thereby, all of the crosslinked portions form an ether bond, and there is no ester bond or a free hydroxyl group which is weak to water. Therefore, it is expected to obtain excellent electrical properties, water resistance, solvent resistance and the like.

However, when a conventional core-shell polymer particle is added to a cationic polymerization type anisotropic conductive film, the affinity between the shell portion and the epoxy resin is insufficient, so that the epoxy resin is deteriorated and the connection resistance is higher. High situation.

The present invention has been made in view of such conventional circumstances, and provides an anisotropic conductive material capable of suppressing deterioration of an epoxy resin and reducing connection resistance.

In order to solve the above problems, the anisotropic conductive material of the present invention is characterized in that an insulating resin containing an epoxy resin, a cationic polymerization initiator, and a core-shell polymer particle having an epoxy group in a shell portion is dispersed. Conductive particles.

Further, in the connector of the present invention, the electrode of the first electronic component and the electrode of the second electronic component are electrically connected to each other by an anisotropic conductive material in which the conductive particles are dispersed in the insulating resin, and the insulating resin is bonded. An epoxy resin, a cationic polymerization initiator, and a core-shell polymer particle having an epoxy group in a shell portion.

According to the present invention, the affinity between the shell portion and the epoxy resin can be improved, and deterioration of the epoxy resin can be suppressed to lower the connection resistance.

Hereinafter, embodiments of the present invention will be described in detail in the following order.

1. Anisotropic conductive material

2. Method for manufacturing anisotropic conductive material

3. Connection method using anisotropic conductive material

4. Examples

<1. Anisotropic conductive material>

The anisotropic conductive material of the present embodiment is one in which an insulating resin containing an epoxy resin, a cationic polymerization initiator, and a core-shell polymer particle having a glycidyl group in a shell portion is dispersed with conductive particles.

As the epoxy resin, a bisphenol epoxy resin, a phenol novolak epoxy resin, an alicyclic epoxy resin, a heterocyclic epoxy resin, a glycidyl ester epoxy resin, or an epoxy resin may be used singly or in combination. A propylamine type epoxy resin, a halogenated epoxy resin, or the like. The content of the epoxy resin is preferably 35 to 95% by mass, more preferably 45 to 75, based on the entire insulating resin (epoxy resin other than the conductive particles, the cationic polymerization initiator, the core-shell polymer particles, etc.). quality%.

Further, in order to improve film formability, it is preferred to mix a phenoxy resin which is a high molecular weight epoxy resin made of epichlorohydrin and bisphenol. When the content of the phenoxy resin is too small, no film is formed, and if it is too large, the repellent property of the resin for obtaining electrical connection tends to be low. Therefore, the resin is preferably 15 to 60% by mass based on the entire insulating resin. Good is 25~45% by mass.

The cationic species of the cationic hardener will open the epoxy group at the end of the epoxy resin and cause the epoxy resins to self-crosslink with each other. Examples of such a cationic hardener include an onium salt such as an aromatic onium salt, an aromatic diazonium salt, a phosphonium salt, a phosphonium salt, and a selenium salt. Especially aromatic sulfonium salts, excellent in reactivity at low temperatures Since it has a long pot life, it is preferred as a cationic hardener.

The core-shell polymer particles are composed of a core portion and a shell portion forming an outer layer of the core portion. The core portion is not particularly limited as long as it does not inhibit the polymerization of the epoxy group to the shell portion. For example, an acrylic rubber polymer, a diene rubber polymer, or an olefin system may be used alone or in combination of two or more. Rubber polymer, etc.

The core portion preferably has a theoretical glass transition temperature of -30 ° C or less as shown by the following formula (1) (FOX formula). If the theoretical glass transition temperature exceeds -30 ° C, it is difficult to obtain a good adhesion strength of the cured product.

1/Tg=W ₁ /T ₁ +W ₂ /T ₂ +...W _n /T _n ...(1)

In the formula (1), W ₁ , W ₂ ... W _n are the mass fractions of the respective monomers, and the glass transition temperatures (K) of the respective monomers of T ₁ and T ₂ ... T _n are.

Specific examples of the monomer forming the core portion include ethyl acrylate (Tg = -22 ° C, only the temperature in parentheses below), n-propyl acrylate (-37 ° C), and n-butyl acrylate (-54). °C), isobutyl acrylate (-24 ° C), butyl acrylate (-21 ° C), n-hexyl acrylate (-57 ° C), 2-ethylhexyl acrylate (-85 ° C), methacrylic acid Octyl ester (-25 ° C), isooctyl acrylate (-45 ° C), n-decyl methacrylate (-35 ° C), n-decyl methacrylate (-45 ° C) and other alkyl (meth) acrylate a conjugated diene monomer composed of carbon atoms of 4 to 6 carbon atoms such as butadiene; vinyl methyl ether (-31 ° C), vinyl ether (-33 ° C), vinyl propyl ether Vinyl ethers such as (-49 ° C). These monomers may be used singly or in combination of two or more kinds. However, from the viewpoints of adjustment of glass transition temperature, adhesion, economy, and the like, a (meth) acrylate monomer is preferably used.

The shell portion has a glycidyl group introduced by polymerization with a core portion. For example, when the core portion is composed of an acrylic rubber polymer, as a polymerizable monomer having a shell portion having a propylene group, a glycidyl methacrylate or a β-methyl methacrylate can be used. Glycidyl acrylate, glycidyl acrylate, and the like.

Preferably, the shell portion of the core-shell polymer particles has an epoxy value of 0.2 eq/kg or more. If the epoxy value is less than 0.2 eq/kg, it is difficult to obtain a good connection resistance as an anisotropic conductive material.

Here, the epoxy value of the shell portion is a ratio of a monomer having an epoxy group contained in the polymerizable monomer composition forming the shell portion. For example, if 1% of glycidyl (meth)acrylate (GMA) is contained in the polymerizable monomer composition, 0.01/142 (GMA molecular weight) = 0.00007 [mol/g], if it is replaced by an equivalent amount The unit becomes 0.07 [eq/kg].

Moreover, it is preferable that the content of the core-shell polymer particles is 20 to 50% by mass based on the entire insulating resin. If the content of the core-shell polymer particles is less than 20% by mass, a good adhesion strength of the cured product cannot be obtained. Further, when the content of the core-shell polymer particles exceeds 5% by mass, it is difficult to obtain a good connection resistance as an anisotropic conductive material.

Further, it is preferred to add a decane coupling agent as another additive composition of the insulating binder resin. As a decane coupling agent, an epoxy group, an amine group, or a fluorenyl group can be used. A sulfide system, a urea group, etc., in the present embodiment, an epoxy decane coupling agent is preferably used. Thereby, the adhesion of the interface between the organic material and the inorganic material can be improved. Further, an inorganic filler may be added. As the inorganic filler, cerium oxide, talc, titanium oxide, calcium carbonate, magnesium oxide can be used. The type of the inorganic filler is not particularly limited. The fluidity can be controlled and the particle capture rate can be improved by the content of the inorganic filler. Further, when blending the respective components of the binder resin, toluene, ethyl acetate, or a mixed solvent thereof can be preferably used.

As the conductive particles, for example, metal particles such as gold particles, silver particles, and nickel particles can be used, and a metal such as a benzoguanamine resin or a styrene resin can be coated with a metal such as gold, nickel or zinc. Coating resin particles and the like. The conductive particles have an average particle diameter of from 1 to 10 μm, more preferably from 2 to 6 μm.

Further, from the viewpoint of connection reliability and insulation reliability, the average particle density of the conductive particles in the insulating adhesive resin is preferably from 1,000 to 50,000/mm ² , more preferably from 3,000 to 30,000/mm ² .

Since the anisotropic conductive material having such a configuration is improved in affinity between the shell portion of the core-shell polymer particles and the epoxy resin, deterioration of the epoxy resin can be suppressed and the connection resistance can be lowered. Moreover, the toughness of the epoxy resin can be enhanced by the core-shell polymer particles to obtain excellent bonding strength.

<2. Method for producing anisotropic conductive material>

Next, a method of producing the above anisotropic conductive material will be described. Here, a method of producing an anisotropic conductive film in which an anisotropic conductive material is formed into a film shape will be described. The method for producing an anisotropic conductive film includes the steps of: preparing a particle-forming step of a core-shell polymer particle having an epoxy group in a shell portion, comprising an epoxy resin, a cationic polymerization initiator, a core-shell polymer particle, And a drying step of applying a composition of the conductive particles to the release substrate to dry the composition on the release substrate.

In the particle production step, first, a solution containing a polymerization initiator is heated and stirred, and a monomer (separate or a combination of two or more) is added dropwise to obtain a core particle (core portion) as a polymer. Then, a solution of a polymerizable monomer composition for forming a shell portion having an epoxy propyl group and a chain transfer agent is added dropwise to a solution for obtaining core particles, and stirred and cooled to prepare core-shell polymer particles. The emulsion is obtained to obtain core-shell polymer particles.

In the coating step, the composition containing the epoxy resin, the cationic polymerization initiator, the core-shell polymer particles, and the conductive particles is adjusted so as to have the above-described configuration, and then a bar coater or a coating device is used. The coating is applied to the release substrate. The release substrate is applied, for example, to a PET (Poly Ethylene Terephthalate, polyethylene terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methylpentene-). 1, a poly-4-methylpentene-1), a PTFE (polytetrafluoroethylene) or the like formed of a laminated structure, while maintaining the shape of the composition while preventing drying of the composition. Further, the composition is obtained by dissolving the above composition in an organic solvent, and the organic solvent may be toluene, ethyl acetate, a mixed solvent thereof, or various other organic solvents.

In the next drying step, the composition on the release substrate is dried by a hot oven, a heating and drying device or the like. Thereby, an anisotropic conductive film in which an electrically conductive particle is dispersed in an insulating binder resin containing an epoxy resin, a cationic polymerization initiator, and core-shell polymer particles can be obtained.

<3. Connection method using an anisotropic conductive material>

Then, the connecting party of the electronic component using the above anisotropic conductive material The method is as follows: an anisotropic conductive material containing an epoxy resin, a cationic polymerization initiator, and a core-shell polymer particle in which an insulating conductive resin is dispersed with a conductive particle is sandwiched between an electrode of the first electronic component and a second electron The first electronic component and the second electronic component are heated and pressurized between the electrodes of the component, and the electrode of the first electronic component is electrically connected to the electrode of the second electronic component. Further, since the anisotropic conductive material in the present embodiment is a cation hardening type, ultraviolet rays and heat can be used singly or in combination.

The anisotropic conductive material of the present embodiment can be used in various cases, but is preferably applied to a first electronic component such as a liquid crystal panel or a printed wiring board (PWB), and the second electronic component is a flexible printed wiring board. A tape-and-reel package (TCP) substrate, a die-bonded film (COF) substrate, or the like.

Since the anisotropic conductive material of the present embodiment is added with the core-shell polymer particles having an epoxy group in the shell portion, deterioration of the epoxy resin of the anisotropic conductive material can be suppressed. Therefore, the connection body in which the electrode of the first electronic component and the electrode of the second electronic component are electrically connected can obtain a stable connection resistance even in a high-temperature and high-humidity reliability test. Further, since the connecting body strengthens the toughness of the epoxy resin by the core-shell polymer particles, excellent bonding strength can be obtained.

[Examples] <2. Example>

Hereinafter, the present invention will be specifically described by way of examples. Here, first, a plurality of core particles A to F having different theoretical glass transition temperatures are prepared, and the core particles A to F are used to form a plurality of core-shell polymer particles having different epoxy values. The samples (samples 1 to 12) were prepared, and an anisotropic conductive material of the examples and comparative examples using the core-shell polymer particles was produced. Then, a connector was produced using the anisotropic conductive materials of the examples and the comparative examples, and the connection resistance and the bonding strength of the connector were evaluated. Furthermore, the invention is not limited by the embodiments.

<Production of nuclear particles> [nuclear particle A]

To a 1 liter round bottom flask, 400 parts by mass of pure water and 0.02 parts by mass of sodium dodecylbenzenesulfonate were added, and the mixture was heated to 80 ° C while stirring. Then, using 0.3 parts by mass of potassium persulfate as a starter, 10% by mass of butyl acrylate and 90% by mass of 2-ethyl acrylate as a polymerizable monomer composition for forming a core portion were added dropwise over 100 minutes. The hexyl ester solution was further stirred for 30 minutes after completion of the dropwise addition to obtain core particles A.

The theoretical glass transition temperature (Tg) of the core particle A was calculated by the following formula (1) (FOX formula) and found to be -82 °C.

1/Tg=W ₁ /T ₁ +W ₂ /T ₂ +...W _n /T _n ...(1)

In the formula (1), W ₁ , W ₂ ... W _n are the mass fractions of the respective monomers, and the glass transition temperatures (K) of the respective monomers of T ₁ and T ₂ ... T _n are.

[nuclear particle B]

The core particles B were obtained in the same manner as in the production method of the core particles A except that a solution containing 90% by mass of butyl acrylate and 10% by mass of ethyl acrylate was used as the polymerizable monomer composition forming the core portion. The theoretical glass transition temperature (Tg) of the core particle B was calculated by the FOX formula and found to be -51.2 °C.

[nuclear particle C]

The core particles C were obtained in the same manner as in the production method of the core particles A, except that a solution containing 30% by mass of butyl acrylate and 70% by mass of ethyl acrylate was used as the polymerizable monomer composition forming the core portion. The theoretical glass transition temperature (Tg) of the core particle C was calculated by the FOX formula and found to be -32.5 °C.

[nuclear particle D]

The core particles D were obtained in the same manner as in the production method of the core particles A, except that a solution containing 100% by mass of ethyl acrylate was used as the polymerizable monomer composition forming the core portion. The theoretical glass transition temperature (Tg) of the core particle D was calculated by the FOX formula and found to be -22.0 °C.

[nuclear particle E]

A core particle E was obtained in the same manner as in the production method of the core particle A except that a solution containing 80% by mass of ethyl acrylate and 20% by mass of methyl methacrylate was used as the polymerizable monomer composition forming the core portion. . The theoretical glass transition temperature (Tg) of the core particle E was calculated by the FOX formula and found to be -3.9 °C.

[nuclear particle F]

A core particle F was obtained in the same manner as in the production method of the core particle A except that a solution containing 60% by mass of ethyl acrylate and 40% by mass of methyl methacrylate was used as the polymerizable monomer composition forming the core portion. . The theoretical glass transition temperature (Tg) of the core particle F was calculated by the FOX formula and found to be 17.0 °C.

The composition of the core particles A to F and the theoretical glass transition temperature (Tg) are shown in Table 1. Further, the average particle diameter of the core particles A to F was measured, and the results were all 0.15. Mm. Further, it was confirmed that the coefficient of variation of the particle diameter was 6%, and the distribution of the particle diameter was extremely small.

<Production of Core-shell Polymer Particles> [sample 1]

After stirring to obtain a solution of the core particle B, 0.2 part by mass of a chain transfer agent was added dropwise to the solution containing 100% by mass of methyl methacrylate as a polymerizable monomer composition forming a shell portion over 100 minutes. a mixture of octyl thioglycolate. After the dropwise addition, the mixture was further stirred for 2 hours, and then cooled to prepare an emulsion of core-shell polymer particles to obtain core-shell polymer particles of Sample 1.

[sample 2]

A core-shell polymer particle of the sample 1 was used, except that a solution containing 98.6% by mass of methyl methacrylate and 1.4% by mass of glycidyl methacrylate was used as the polymerizable monomer composition forming the shell portion. The core-shell polymer particles of Sample 2 were obtained in the same manner as in the production method. The epoxy value of the shell portion is a ratio of a monomer having an epoxy group contained in the polymerizable monomer composition forming the shell portion, and the epoxy group is introduced into the shell portion at the same ratio. In the sample 2, the polymerizable monomer composition contained 1.4% by mass of (meth) propyl group. Glycidyl acrylate (GMA), therefore 0.014/142 (GMA molecular weight) = 0.0001 [mol/g], and 0.1 [eq/kg] if replaced with equivalent units.

[sample 3]

A core-shell polymer particle of the sample 1 was used, except that a solution containing 97.1% by mass of methyl methacrylate and 2.9% by mass of glycidyl methacrylate was used as the polymerizable monomer composition forming the shell portion. The core-shell polymer particles of Sample 3 were obtained in the same manner as in the production method. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 3, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 0.2 [eq/kg].

[Sample 4]

A core-shell polymer particle of the sample 1 was used, except that a solution containing 99.7% by mass of methyl methacrylate and 4.3% by mass of glycidyl methacrylate was used as the polymerizable monomer composition forming the shell portion. The core-shell polymer particles of Sample 4 were obtained in the same manner as in the production method. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 4, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 0.3 [eq/kg].

[Sample 5]

A core-shell polymer particle of the sample 1 was used, except that a solution containing 91.4% by mass of methyl methacrylate and 8.6% by mass of glycidyl methacrylate was used as the polymerizable monomer composition forming the shell portion. The core-shell polymer particles of Sample 5 were obtained in the same manner as in the production method. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 5, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 0.6 [eq/kg].

[Sample 6]

A core-shell polymer particle of the sample 1 was used, except that a solution containing 85.7 mass% of methyl methacrylate and 14.3 mass% of glycidyl methacrylate was used as the polymerizable monomer composition forming the shell portion. The core-shell polymer particles of Sample 6 were obtained in the same manner as in the production method. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 6, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 1.0 [eq/kg].

[sample 7]

The core of the sample 7 was obtained in the same manner as the method of producing the core-shell polymer particles of the sample 1, except that a solution containing 100% by mass of glycidyl methacrylate was used as the polymerizable monomer composition forming the shell portion. Shell polymer particles. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 7, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 7.0 [eq/kg].

[Sample 8]

A sample obtained by obtaining a core particle A and using a solution containing 91.4% by mass of methyl methacrylate and 8.6% by mass of glycidyl methacrylate as a polymerizable monomer composition forming a shell portion, and a sample The core-shell polymer particles of Sample 8 were obtained in the same manner as in the preparation of the core-shell polymer particles of 1. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 8, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 0.6 [eq/kg].

[Sample 9]

A solution containing the core particle C was used and a solution containing 91.4% by mass of methyl methacrylate and 8.6% by mass of glycidyl methacrylate was used. The core-shell polymer particles of the sample 9 were obtained in the same manner as in the production method of the core-shell polymer particles of the sample 1, as the polymerizable monomer composition forming the shell portion. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 9, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 0.6 [eq/kg].

[Sample 10]

A sample obtained by obtaining a core particle D and using a solution containing 91.4% by mass of methyl methacrylate and 8.6% by mass of glycidyl methacrylate as a polymerizable monomer composition forming a shell portion, and a sample The core-shell polymer particles of Sample 10 were obtained in the same manner as in the preparation of the core-shell polymer particles of 1. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 10, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 0.6 [eq/kg].

[Sample 11]

A sample obtained by obtaining a core particle E and using a solution containing 91.4% by mass of methyl methacrylate and 8.6% by mass of glycidyl methacrylate as a polymerizable monomer composition forming a shell portion, and a sample The core-shell polymer particles of Sample 11 were obtained in the same manner as in the preparation of the core-shell polymer particles of 1. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 11, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 0.6 [eq/kg].

[Sample 12]

A solution containing the core particle F was used and a solution containing 91.4% by mass of methyl methacrylate and 8.6% by mass of glycidyl methacrylate was used. The core-shell polymer particles of the sample 12 were obtained in the same manner as in the production method of the core-shell polymer particles of the sample 1, as the polymerizable monomer composition forming the shell portion. With respect to the epoxy value of the shell portion of the core-shell polymer particles of the sample 12, the ratio of GMA contained in the polymerizable monomer composition forming the shell portion was calculated and found to be 0.6 [eq/kg].

The composition and epoxy value of the core-shell particles of Samples 1 to 12 are shown in Table 2. Further, the particle size of the core-shell polymer particles of the samples 1 to 12 finally obtained was all 0.19 μm, and the coefficient of variation was 6%.

<Preparation of anisotropic conductive material, fabrication of a connector, measurement of connection resistance, and measurement of adhesion strength> [Example 1]

30 parts by mass of phenoxy resin (product name: YP-50, manufactured by Nippon Steel Chemical Co., Ltd.), 30 parts by mass of epoxy resin (product name: EP-828, manufactured by Mitsubishi Chemical Corporation), 30 parts by mass Core-shell polymer particles of sample 2, 1 part by mass of decane coupling agent (product name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) and 4 parts by mass of hardener (product name: SI-60L, manufactured by Sanshin Chemical Co., Ltd.) In the adhesive agent, the conductive particles (product name: AUL704, manufactured by Sekisui Chemical Co., Ltd.) were dispersed so as to have a particle density of 10,000 particles/mm ² to prepare a cationic hardening of Example 1 having a thickness of 20 μm. The tie electrode is then used with a sheet.

[Production of connector]

COF (50 μmP, Cu 8 μmt-plated Sn, 38 μm-Sperflex substrate) and IZO coated glass (IZO coated on the entire surface, glass thickness 0.7 mm) were bonded as an evaluation substrate. The above cationic hardening electrode was then cut into a sheet of 1.5 mm width and attached to an IZO coated glass. After the COF was temporarily fixed thereto, the joint was completed by bonding using a heating tool of 1.5 mm width and using a buffer material of 100 μm Teflon at a bonding condition of 190 ° C - 3 MPa - 5 sec.

[Measurement of connection resistance of connector]

The connection resistance after the initial test and the reliability test at 85 ° C / 85% / 500 hr was measured. For the measurement, a digital multimeter (product number: digital multimeter 7555, manufactured by Yokogawa Electric Co., Ltd.) was used, and the connection resistance at a current of 1 mA was measured by a 4-terminal method. As a result, the initial connection resistance of the connector to which the anisotropic conductive material of Example 1 was used was 2.1 Ω, and the connection resistance after the reliability test was 5.5 Ω.

[Measurement of the bonding strength of the connector]

The adhesion strength after the initial test and the reliability test at 85 ° C / 85% / 500 hr was measured for each of the mounts. The test system uses a tensile tester (product number: RTC1201, manufactured by AND Corporation) The subsequent strength at which the COF was pulled at a measurement rate of 50 mm/sec was measured. As a result, the initial strength of the joined body to which the anisotropic conductive material of Example 1 was bonded was 7.0 N/cm, and the adhesive strength after the reliability test was 4.3 N/cm.

[Embodiment 2]

A cation hardening electrode of Example 2 was used in the same manner as in Example 1 except that the core-shell polymer particles of Sample 3 were used. The initial connection resistance of the connecting body to which the anisotropic conductive material of Example 2 was used was 2.0 Ω, and the connection resistance after the reliability test was 4.3 Ω. Further, the initial strength of the joined body was 7.1 N/cm, and the adhesion strength after the reliability test was 5.0 N/cm.

[Example 3]

A cation hardening electrode of Example 3 was used in the same manner as in Example 1 except that the core-shell polymer particles of Sample 4 were used. The initial connection resistance of the connector to which the anisotropic conductive material of Example 3 was used was 2.1 Ω, and the connection resistance after the reliability test was 4.0 Ω. Further, the initial strength of the joined body was 7.0 N/cm, and the subsequent strength after the reliability test was 5.5 N/cm.

[Example 4]

A cation hardening electrode of Example 4 was used in the same manner as in Example 1 except that the core-shell polymer particles of Sample 5 were used. The initial connection resistance of the connector to which the anisotropic conductive material of Example 4 was used was 2.1 Ω, and the connection resistance after the reliability test was 3.7 Ω. Moreover, the initial strength of the joint was 7.3 N/cm, after the reliability test The subsequent strength is 6.2 N/cm.

[Example 5]

A cation hardening electrode of Example 5 was used in the same manner as in Example 1 except that the core-shell polymer particles of Sample 6 were used. The initial connection resistance of the bonded body to which the anisotropic conductive material of Example 5 was used was 2.0 Ω, and the connection resistance after the reliability test was 4.1 Ω. Further, the initial strength of the joined body was 7.0 N/cm, and the adhesive strength after the reliability test was 6.0 N/cm.

[Embodiment 6]

A cation hardening electrode of Example 6 was used in the same manner as in Example 1 except that the core-shell polymer particles of Sample 7 were used. The initial connection resistance of the connector to which the anisotropic conductive material of Example 6 was used was 2.1 Ω, and the connection resistance after the reliability test was 3.8 Ω. Further, the initial strength of the joined body was 7.1 N/cm, and the adhesion strength after the reliability test was 6.0 N/cm.

[Embodiment 7]

A cation hardening electrode of Example 7 was used in the same manner as in Example 1 except that the core-shell polymer particles of Sample 8 were used. The initial connection resistance of the connecting body to which the anisotropic conductive material of Example 7 was used was 2.0 Ω, and the connection resistance after the reliability test was 4.0 Ω. Further, the initial strength of the joined body was 7.5 N/cm, and the adhesion strength after the reliability test was 6.2 N/cm.

[Embodiment 8]

Except that the core-shell polymer particles of sample 9 were used, and Example 1 The cation hardening electrode of Example 8 was produced in the same manner as the sheet. The initial connection resistance of the connector to which the anisotropic conductive material of Example 8 was used was 2.1 Ω, and the connection resistance after the reliability test was 3.8 Ω. Further, the initial strength of the joined body was 6.9 N/cm, and the adhesion strength after the reliability test was 5.1 N/cm.

[Embodiment 9]

A cation hardening electrode of Example 9 was used in the same manner as in Example 1 except that the core-shell polymer particles of Sample 10 were used. The initial connection resistance of the bonded body to which the anisotropic conductive material of Example 9 was used was 2.0 Ω, and the connection resistance after the reliability test was 3.7 Ω. Further, the initial strength of the joined body was 6.9 N/cm, and the adhesion strength after the reliability test was 4.7 N/cm.

[Embodiment 10]

A cation hardening electrode of Example 10 was used in the same manner as in Example 1 except that the core-shell polymer particles of Sample 11 were used. The initial connection resistance of the connector to which the anisotropic conductive material of Example 10 was used was 2.1 Ω, and the connection resistance after the reliability test was 3.8 Ω. Further, the initial strength of the joined body was 6.0 N/cm, and the adhesion strength after the reliability test was 4.5 N/cm.

[Example 11]

A cation hardening electrode of Example 11 was used in the same manner as in Example 1 except that the core-shell polymer particles of Sample 12 were used. The initial connection resistance of the connector to which the anisotropic conductive material of Example 11 was used was 2.1 Ω, and the connection resistance after the reliability test was 3.7 Ω. Further, the initial strength of the joined body was 5.5 N/cm, and the adhesive strength after the reliability test was 3.0 N/cm.

[Embodiment 12]

Example 12 was produced in the same manner as in Example 1 except that the phenoxy resin was 50 parts by mass, the epoxy resin was 35 parts by mass, and the core-shell polymer particles of the sample 5 were 10 parts by mass. The cation hardening electrode is followed by a sheet. The initial connection resistance of the connecting body to which the anisotropic conductive material of Example 12 was used was 2.0 Ω, and the connection resistance after the reliability test was 3.4 Ω.

Further, the initial strength of the joined body was 6.0 N/cm, and the adhesion strength after the reliability test was 4.0 N/cm.

[Example 13]

A cationic hardening electrode of Example 13 was produced in the same manner as in Example 1 except that 45 parts by mass of phenoxy resin, 30 parts by mass of epoxy resin, and 20 parts by mass of core-shell polymer particles of Sample 5 were used. Then use a sheet. The initial connection resistance of the connecting body to which the anisotropic conductive material of Example 13 was used was 2.2 Ω, and the connection resistance after the reliability test was 3.6 Ω.

Further, the initial strength of the joined body was 6.9 N/cm, and the adhesive strength after the reliability test was 5.0 N/cm.

[Embodiment 14]

Example 14 was produced in the same manner as in Example 1 except that the phenoxy resin was 25 parts by mass, the epoxy resin was 20 parts by mass, and the core-shell polymer particles of the sample 5 were 50 parts by mass. The cation hardening electrode is followed by a sheet. Using the anisotropic conductive material of the embodiment 14 to connect The initial connection resistance of the connector was 2.1 Ω, and the connection resistance after the reliability test was 4.4 Ω.

Further, the initial strength of the joined body was 7.5 N/cm, and the adhesion strength after the reliability test was 6.2 N/cm.

[Example 15]

Example 15 was produced in the same manner as in Example 1 except that the phenoxy resin was 15 parts by mass, the epoxy resin was 20 parts by mass, and the core-shell polymer particles of the sample 5 were 60 parts by mass. The cation hardening electrode is followed by a sheet. The initial connection resistance of the connector to which the anisotropic conductive material of Example 15 was used was 2.0 Ω, and the connection resistance after the reliability test was 4.7 Ω.

Further, the initial strength of the joined body was 7.5 N/cm, and the adhesion strength after the reliability test was 6.3 N/cm.

[Comparative Example 1]

The cation of Comparative Example 1 was produced in the same manner as in Example 1 except that the core-shell polymer particles (0 parts by mass) were not used, and the phenoxy resin was 60 parts by mass, and the epoxy resin was 35 parts by mass. The hardened electrode is then a sheet. The initial connection resistance of the bonded body to which the anisotropic conductive material of Comparative Example 1 was used was 2.0 Ω, and the connection resistance after the reliability test was 3.3 Ω. Further, the initial strength of the joined body was 5.1 N/cm, and the subsequent strength after the reliability test was 0.7 N/cm.

[Comparative Example 2]

A cation hardening electrode of Comparative Example 2 was produced in the same manner as in Example 1 except that the core-shell polymer particles of Sample 1 were used. material. The initial connection resistance of the connector to which the anisotropic conductive material of Comparative Example 2 was connected was 2.1 Ω, and the connection resistance after the reliability test was 7.0 Ω. Further, the initial strength of the joined body was 7.2 N/cm, and the adhesion strength after the reliability test was 4.0 N/cm.

Table 3 shows the blending amount of the core-shell polymer particles in the sheet of the cation hardening electrode of the above Examples and Comparative Examples, the epoxy value, the theoretical glass transition temperature, and the connection resistance and the subsequent strength of the joined body.

<evaluation>

Examples 1 to 15 containing core-shell polymer particles having a carboxyl group having a shell portion were superior to Comparative Example 1 containing no core-shell polymer particles, and were excellent in the initial stage of the linker and after the reliability test. strength.

Further, in Examples 1 to 15 including the core-shell polymer particles having a glycidyl group in the shell portion, compared with Comparative Example 2 containing the core-shell polymer particles having no epoxy group in the shell portion, in the initial stage of the bonded body Excellent connection resistance is obtained after the reliability test.

The reason is considered to be that the affinity between the shell portion and the epoxy resin is improved, and the deterioration of the epoxy resin is suppressed.

Further, by setting the epoxy value of the shell portion of the core-shell polymer particles to 0.2 eq/kg or more as in Examples 2 to 6, a stable connection resistance can be obtained even after the reliability test.

Further, by subjecting the core glass transition temperature of the core portion of the core-shell polymer particles to -30 ° C or lower as in Example 4 and Examples 7 and 8, stable post-strength strength was obtained even after the reliability test.

Further, by including 20 to 50% by mass of the core-shell polymer particles in the insulating adhesive resin as in Example 4 and Examples 13 and 14, stable connection resistance and subsequent strength can be obtained even after the reliability test. .

Claims (9)

An anisotropic conductive material in which an electrically conductive particle is dispersed in an insulating binder resin containing an epoxy resin, a cationic polymerization initiator, and a core-shell polymer particle having an epoxy group in a shell portion. The anisotropic conductive material of claim 1, wherein the core portion of the core-shell polymer particles is composed of an acrylic rubber polymer and has a ring derived from glycidyl (meth)acrylate in the shell portion. Oxypropyl. The anisotropic conductive material according to claim 1 or 2, wherein the shell portion of the core-shell polymer particles has an epoxy value of 0.2 eq/kg or more. The anisotropic conductive material according to claim 1 or 2, wherein the core glass transition temperature of the core portion of the core-shell polymer particles is -30 ° C or lower. The anisotropic conductive material according to claim 3, wherein the core glass transition temperature of the core portion of the core-shell polymer particles is -30 ° C or lower. The anisotropic conductive material according to claim 1 or 2, wherein the core-shell polymer particles are contained in the insulating binder resin in an amount of 20 to 50% by mass. The anisotropic conductive material according to claim 3, wherein the content of the core-shell polymer particles in the insulating binder resin is 20 to 50% by mass. The anisotropic conductive material of claim 4, wherein the core-shell polymer particles are contained in the insulating binder resin in an amount of 20 to 50% by mass. A connector for electrically connecting an electrode of a first electronic component to an electrode of a second electronic component, wherein the insulating resin comprises an epoxy resin or a cation, by using an anisotropic conductive material in which an insulating resin is dispersed with a conductive particle. A polymerization initiator and a core-shell polymer particle having an epoxy group at a shell portion.