JP2018131569A - Resin composition comprising conductive particles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition capable of forming an adhesion part which can be hardened even at a low temperature and has sufficient conductivity and connection reliability.SOLUTION: There is provided a resin composition which comprises conductive particles, an epoxy resin, a phenoxy resin and a curing agent and comprises solder particles as the conductive particles, wherein the epoxy resin is one or more selected from a bisphenol type epoxy resin, a phenol novolac type epoxy resin, a biphenyl type epoxy resin, a naphthalene type epoxy resin, a dicyclopentadiene type epoxy resin, a triglycidyl isocyanurate, a cyclohexane type epoxy resin and an adamantane type epoxy resin and the curing agent is one or more compounds selected from the group consisting of an epoxy resin amine adduct compound, an epoxy resin imidazole adduct compound and a modified aliphatic polyamine compound.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a resin composition containing conductive particles, and in particular, a resin containing conductive particles that can be used as an anisotropic conductive adhesive used for connection between wiring boards or between an electronic component and a wiring board. Relates to the composition.

  In recent years, for example, a connection method using an anisotropic conductive adhesive in a paste state or a film / sheet state has been used to join a flexible substrate and a rigid substrate or to electrically connect an electronic component and a wiring substrate. Yes.

  As an anisotropic conductive adhesive, for example, a thermosetting resin for securing electrical insulation and adhesive strength, a conductive material such as a solder material such as a metal coating such as gold, silver, nickel, etc. The thing etc. which mix | blended particle | grains are proposed (for example, patent document 1). By using such an anisotropic conductive adhesive, for example, by crimping an electronic component and a wiring board, the electrodes are brought into contact with each other by conductive particles, thereby ensuring conductivity. . On the other hand, since the conductive particles exist in the gap between the electrodes of the electronic component and the wiring board, the conductive particles are embedded in the above-described resin. Sufficient adhesion is ensured.

JP 2012-67281 A

  However, in the conventional anisotropic conductive adhesive, for example, when solder particles are used as the conductive particles, the connection can be ensured with a low load by melting the solder particles. A relatively high temperature (for example, 140 to 190 ° C.) was required for curing the resin necessary for ensuring the above. For this reason, for example, a glass substrate, a glass epoxy substrate, a flexible printed circuit board, etc., the amount of distortion and warpage of the substrates to be joined is increased, and the mounting of LCD modules that are becoming larger, narrower and thinner. In such a case, there is a problem that display quality is deteriorated due to such distortion and warpage.

  Therefore, in the present invention, a resin composition containing conductive particles such as solder particles, which can be cured even at a low temperature and can form an adhesive part having sufficient conductivity and connection reliability. An object is to provide a composition.

  In order to achieve the above object, a resin composition containing the conductive particles of the present invention (hereinafter sometimes abbreviated as “resin composition”) includes conductive particles, an epoxy resin, a phenoxy resin, and a curing agent. The epoxy resin is a bisphenol type epoxy resin, a phenol novolac type epoxy resin, a biphenyl type epoxy resin, a naphthalene type epoxy resin, a dicyclopentadiene type epoxy resin, It is at least one epoxy resin selected from the group consisting of glycidyl isocyanurate, cyclohexane type epoxy resin and adamantane type epoxy resin, and the curing agent is an epoxy resin amine adduct compound, an epoxy resin imidazole adduct compound, and a modified aliphatic polyamine Composed of compounds At least one compound selected from the group consisting of: a solder particle content in the range of 1% by mass to 40% by mass with respect to the total mass of the resin composition; and the epoxy resin and the phenoxy resin. When the total mass of the curing agent is 100 parts by mass, the epoxy resin is included at a rate of 12 parts by mass or more, the phenoxy resin is included at a rate of 12 parts by mass or more, and the curing agent is 12 parts by mass. It is characterized by being contained in a proportion of not less than 58 parts by mass.

  In the resin composition of the present invention, the solder particles may be a Bi-In alloy. At this time, the Bi content in the solder particles is in the range of 33% by mass to 85% by mass with respect to the total mass of the solder particles, and the Bi content is 33% with respect to the total mass of the solder particles. It is preferable to be in the range of mass% to 85 mass%.

  In the resin composition of the present invention, when the total mass of the epoxy resin, the phenoxy resin and the curing agent is 100 parts by mass, the epoxy resin is preferably contained in a proportion of 15 parts by mass or more and 55 parts by mass or less. Moreover, it is preferable at this time that a phenoxy resin is contained in the ratio of 12 to 76 mass parts. Furthermore, when the total mass of the epoxy resin, the phenoxy resin, and the curing agent is 100 parts by mass, the curing agent is preferably included in a proportion of 15 parts by mass or more and 55 parts by mass or less.

  According to the present invention, a resin composition containing conductive particles such as solder particles, which can be cured even at a low temperature, and an adhesive portion having sufficient conductivity and connection reliability can be formed. A resin composition is provided. Since it can be cured at low temperatures, the amount of distortion and warpage of the substrate is reduced in the manufacture of LCD modules, etc., and good electrical connection with less distortion is possible, thus providing a high-quality product. Will be able to.

It is a schematic cross section of the resin composition containing the electroconductive particle in embodiment of this invention. It is a schematic cross section of the joined body of the glass substrate and flexible substrate produced using the resin composition containing the electroconductive particle in embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view of a resin composition containing conductive particles in an embodiment of the present invention. In FIG. 1, the resin composition 1 includes conductive particles 2 and a resin component 3, and the conductive particles 2 are dispersed in the resin component 3. The resin composition 1 preferably has a film-like or sheet-like shape having a cross section as illustrated. Solder particles are used as the conductive particles 2, and the resin component 3 contains an epoxy resin, a phenoxy resin, and a curing agent. The insulating property and adhesiveness of the resin composition 1 are brought about by the resin component 3, and the conductive particles 2 are preferably dispersed uniformly in the resin component 3. Hereinafter, each component will be described in detail.

[Conductive particles]
Solder particles are used for the conductive particles 2. By using solder particles as the conductive particles 2, it is possible to reduce the load applied during bonding by heating the solder particles to a melting point or higher to melt the solder particles. For the solder particles, any material having electrical conductivity can be used. For example, a pure metal such as Sn, In, Bi, or an alloy containing these elements can be used, but it is not limited thereto. As the solder particles, it is preferable to use a Bi—In alloy containing Bi and In or a Sn—In alloy containing Sn and In, and it is particularly preferable to use a Bi—In alloy. . Since a Bi—In alloy has a melting point of 85 ° C. or higher and 100 ° C. or lower, bonding can be performed at a low temperature of 130 ° C. or lower. In addition, the manufacturing cost can be reduced by using a Bi-In alloy for the solder particles.

  The composition of the solder powder in this specification is expressed by connecting element symbols of elements contained in the solder powder with hyphens. In the present specification, to describe the metal composition of the solder powder, a numerical value or a numerical range may be indicated immediately before the metal element, and this is a common practice in the art. The mass% (=% by weight) of each element in the composition is indicated by a numerical value or a numerical range. The solder powder may contain trace metals that are inevitably mixed as long as the solder powder is substantially composed of the listed elements.

  The Bi content in the solder particles which are Bi-In alloys may be in the range of 33% by weight to 85% by weight, preferably 40% by weight to 85% by weight, based on the total weight of the solder particles. % Or less. When the content of the solder particles is within the above range, the solder particles can be melted at a temperature sufficiently lower than the curing temperature of the resin component. In addition, when manufacturing an LCD module or the like, the load applied to the resin composition can be reduced, and as a result, the stress on the substrate can be greatly reduced.

  The average particle size of the solder particles is in the range of 1 μm to 20 μm, preferably 3 μm to 10 μm. When the average particle size of the solder particles is 1 μm or more, the reliability of the electrical connection between the solder particles is increased, and when the solder particle is 20 μm or less, the solder particles are interposed between the adjacent electrodes, thereby causing a short circuit. The possibility of being caused can be significantly reduced.

  In the present specification, the average particle size is a particle size (D50) at which the cumulative value is 50% in a cumulative curve obtained by obtaining a particle size distribution on a volume basis and setting the total volume to 100%. The average particle diameter can be measured using a laser diffraction / scattering particle diameter / particle size distribution measuring apparatus or an electronic scanning microscope.

  The content of the solder particles is in the range of, for example, 1% by mass to 40% by mass, preferably 3% by mass to 30% by mass, based on the total mass of the resin composition (as 100% by mass). When the solder particle content is 1% by mass or more, sufficient electrical conductivity of the resin composition and reliability of electrical connection can be secured, and when the solder particle content is 40% by mass or less, contact between adjacent solder particles is achieved. In addition, the possibility that a short circuit or the like is caused by the presence of solder particles between adjacent electrodes can be significantly reduced.

[Epoxy resin]
By including an epoxy resin in the resin component 3, the adhesiveness of the resin composition is improved, the resin fluidity during heating is improved, and the ease of handling (handling) during formation is improved. As the epoxy resin, for example, various epoxy resins such as glycidyl ether type, glycidyl amine type, glycidyl ester type, and olefin oxidation type (alicyclic) can be used. For example, phenol novolac type epoxy resin, alkylphenol novolak type epoxy resin, naphthalene-containing novolak type epoxy resin, bisphenol A novolak type epoxy resin, triphenylmethane type (trisphenolmethane type) epoxy resin, tetrakisphenolethane type epoxy resin, dicyclo Pentadiene type epoxy resin, phenol biphenyl type epoxy resin, novolac type epoxy resin such as mixture of crystalline epoxy resin and novolak type epoxy resin, bisphenol type epoxy resin, biphenyl type epoxy resin, stilbene type epoxy resin, naphthalene type epoxy resin, Alicyclic epoxy resin, bromine-containing epoxy resin, cyclohexane type epoxy resin, adamantane type epoxy resin and triglycidyl isocyanate It can be used rates. These epoxy resins can be used singly, and a plurality of types of epoxy resins can be arbitrarily combined and used as necessary. Those exhibiting fluidity at the time of overheating and high adhesiveness after heat curing are preferably used. Among them, for example, bisphenol type A type resin and bisphenol F type, bisphenol type epoxy resin, phenol novolac type epoxy resin, biphenyl type Epoxy resins, naphthalene type epoxy resins, dicyclopentadiene type epoxy resins, cyclohexane type epoxy resins, adamantane type epoxy resins, glycidyl ether group-containing type epoxy resins and triglycidyl isocyanurate are particularly preferably used.

  The equivalent of the epoxy resin used in the present invention is, for example, 150 or more, preferably 160 or more and 250 or less, more preferably 170 or more and 200 or less. When the equivalent amount of the epoxy resin is within the above range, the adhesiveness of the resin composition is effectively improved, the resin fluidity during heating is further improved, and the formability to a film or sheet is improved.

  The content of the epoxy resin is 12 parts by mass or more, preferably 15 parts by mass or more and 55 parts by mass or less, more preferably 20 parts when the total mass of the epoxy resin, the phenoxy resin and the curing agent is 100 parts by mass. It may be in the range of not less than 55 parts by mass. When content of an epoxy resin exists in such a range, the adhesiveness of a resin composition is improved effectively, and the formability to a film or a sheet improves.

[Phenoxy resin]
By including a phenoxy resin in the resin component 3, flexibility is imparted to the resin composition, and adhesion to the substrate can be improved. As the phenoxy resin, for example, a phenoxy resin having a skeleton such as a bisphenol A skeleton, a bisphenol F skeleton, a bisphenol S skeleton, a biphenyl skeleton, a novolak skeleton, a naphthalene skeleton, and an imide skeleton can be used. It is preferable to use one or more phenoxy resins containing any of the skeletons described above.

  The weight average molecular weight of the phenoxy resin is, for example, 30000 or more, preferably 35,000 to 100,000, more preferably 38,000 to 70,000. When the weight average molecular weight of the phenoxy resin is within the above range, a stable film can be formed. Moreover, since the softening point is in the range of about 80 ° C. to about 160 ° C., it is solid at ordinary temperature and behaves as a thermoplastic resin, the film and sheet formability of the resin composition can be improved.

  The content of the phenoxy resin is 12 parts by mass or more, preferably 12 parts by mass or more and 76 parts by mass or less when the total mass of the epoxy resin, the phenoxy resin, and the curing agent is 100 parts by mass. When the mass part of the epoxy resin is within the above range, it is easy to produce a solid anisotropic conductive material from the resin composition, and for example, it is easy to form a sheet, a film, or the like. In addition, it is possible to prevent a decrease in adhesive strength due to insufficient curing of the resin component and to suppress instability of connection resistance.

[Curing agent]
By including a curing agent in the resin component 3, the resin composition can be cured at a low temperature. Examples of the curing agent include an epoxy resin amine adduct compound, an epoxy resin imidazole adduct compound, and a modified aliphatic polyamine compound. The epoxy resin amine adduct compound is a reaction product of an epoxy compound and an amine compound (generally called an epoxy compound amine adduct). Specifically, the substituent has at least one active hydrogen capable of undergoing an addition reaction with an epoxy group of a monofunctional or polyfunctional epoxy compound, and is selected from primary, secondary, and tertiary amino groups. Is a reaction product (namely, epoxy compound amine adduct) with an amine compound having at least one in a molecule. An epoxy resin imidazole adduct compound is a curing agent that is stable even in a mixed system with an epoxy resin, and can obtain a cured product having a high heat distortion temperature by heat treatment at 80 ° C. or more and 120 ° C. or less together with the epoxy resin. Yes, it is a solid that is insoluble in general epoxy resins that are liquid near room temperature, but is solubilized by heating and exhibits its original function. A modified aliphatic polyamine compound is a curing agent that is stable even in a mixed system with an epoxy resin, and that provides a cured product exhibiting a high heat distortion temperature by heat treatment at 80 to 120 ° C., and is a general epoxy resin that is liquid near room temperature Although it is an insoluble solid, it is a compound that is solubilized by heating and exhibits its original function. The basis is a reaction product of an amine compound and an isocyanate compound (generally called an aliphatic polyamine modified product). Specifically, it is a dialkylaminoalkylamine compound, a cyclic amine compound having one or more nitrogen atoms having active hydrogen in the molecule, and a reaction product of a diisocyanate compound (that is, a modified aliphatic polyamine). In the present invention, an epoxy resin amine adduct compound, an epoxy resin imidazole adduct compound, a modified aliphatic polyamine compound or the like may be used alone, or two or more kinds may be selected and used, and in particular, an epoxy resin amine adduct compound is used. Thus, sufficient curability at a temperature of 130 ° C. or less can be secured.

  The content of the curing agent is 12 parts by mass or more and 58 parts by mass or less, preferably 15 parts by mass or more and 55 parts by mass or less when the total mass of the epoxy resin, the phenoxy resin, and the curing agent is 100 parts by mass. Preferably, it exists in the range of 20 to 50 mass parts. When the content of the curing agent is within the above range, it is easy to produce a solid anisotropic conductive material from the resin composition, and for example, it is easy to form into a sheet or a film. In addition, it is possible to prevent a decrease in adhesive strength due to insufficient curing of the resin component and to suppress instability of connection resistance.

[Other ingredients]
The resin composition of the present embodiment may contain any component other than those described above, for example, a coupling agent or the like. For example, the adhesiveness of the resin composition can be improved by including a coupling agent.

  FIG. 2 is a schematic cross-sectional view of a joined body of a glass substrate and a flexible substrate manufactured using a resin composition containing conductive particles according to an embodiment of the present invention. In FIG. 2, the flexible substrate 4 having the Au plating portion 5 and the glass substrate 7 on which ITO 6 is deposited are bonded by the resin composition of the present invention. In FIG. 2, the flexible substrate 4 and the glass substrate 7 are pressure-bonded so that they are in contact with each other via the conductive particles 2 contained in the resin composition therebetween, and the conductivity is ensured. The production method and use method of the resin composition of the present invention used in this manner will be further described below.

[Method for Producing Resin Composition]
The resin composition of the said embodiment of this invention can be manufactured by mixing the electroconductive particle mentioned above, an epoxy resin, a phenoxy resin, and a hardening | curing agent with a mixer etc., for example. At this time, the phenoxy resin may be previously dissolved in a solvent and then mixed with other components. In this case, as the solvent, any solvent capable of dissolving the phenoxy resin can be used. For example, from the viewpoint of moldability, the solvent has a low vapor pressure and a boiling point of 100 ° C. or less. Specifically, it is preferable to use toluene, methyl ethyl ketone, ethyl acetate or the like alone or in combination.

  Furthermore, you may shape | mold a resin composition in shapes, such as a film form or a sheet form, using a bar coater etc. At this time, the thickness of the resin composition after molding can be appropriately set according to the use, but it is usually preferably in the range of 10 μm to 30 μm. In addition, although the resin composition containing the electroconductive particle of this invention can take arbitrary shapes, for example, it can be used by a paste form, a film form, and a sheet form, However, It is not limited to these.

[Usage method of resin composition]
The resin composition of the present invention can be cured by heating, and by applying pressure at the same time, the conductive particles can be exposed at both end surfaces to provide conductivity. The heating temperature at this time is 80 degreeC-150 degreeC, for example, Preferably it is 90 degreeC-130 degreeC, More preferably, it is 90 degreeC-110 degreeC. The pressure applied at this time is, for example, 0.5 MPa or more and 5 MPa or less, preferably 0.5 MPa or more and 3 MPa or less. The time of heating and / or pressurization may be, for example, 5 seconds to 20 seconds, preferably 8 seconds to 15 seconds.

  The resin composition of the above embodiment of the present invention exhibits excellent conductivity and connection reliability after the heating and pressurization described above. EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in more detail, this invention is not limited to a following example.

  Conductive particles, an epoxy resin, a phenoxy resin, and a curing agent were mixed in an arbitrary amount and kneaded by a rotation / revolution mixer to prepare pastes of Examples 1 to 10 and Comparative Examples 1 to 6. Here, the phenoxy resin was dissolved in advance using toluene and ethyl acetate, and added to the paste so as to have a predetermined solid content and kneaded. Subsequently, the paste prepared as described above was applied using a bar coater so as to have a film thickness of 15 μm to 20 μm, and dried at room temperature, whereby Examples 1 to 10 and Comparative Examples 1 to 6 were used. A sheet-like resin composition was obtained. In Examples 1 to 10 and Comparative Examples 1 to 6, the types of components to be kneaded are not changed, but the blending amounts are changed. As the epoxy resin, jER828, which is a bisphenol A type epoxy resin manufactured by Mitsubishi Chemical Corporation, and EP-4088L, which is a dicyclopentadiene type epoxy resin manufactured by ADEKA Corporation, were used. As the phenoxy resin, PKHC manufactured by Sakai Kogyo Co., Ltd. having a bisphenol FA type skeleton was used. As the curing agent, EH-5030S, which is an epoxy resin amine adduct compound manufactured by ADEKA Corporation, was used. As the conductive particles, Bi-In (55Bi-45In) solder particles having an average particle size in the range of 3 μm to 5 μm were used.

  The compounding amounts of the components of the resin compositions in Examples 1 to 10 and Comparative Examples 1 to 6 of the present invention are shown in Tables 1 and 2 below. In the table, the blending amounts of epoxy resin, phenoxy resin, curing agent and solder particles represent the ratio when the total mass of the entire resin component is 100 parts by mass, and the unit is mass parts. In the table, the ratio of the mass of the resin component and the conductive particles to the mass of the entire resin composition is shown in units of percent (%).

  For the purpose of evaluating the peel adhesion strength and connection resistance value of the resin compositions prepared in Examples and Comparative Examples, as shown in FIG. 2, a glass substrate 7 on which ITO 6 is deposited and a polyimide having an Au plating portion 5 are used. The flexible substrate 4 was prepared. The size of the glass substrate 7 was 30 mm × 30 mm × 0.3 mm, and the thickness of the ITO 6 was 2000-2500 mm (200-250 nm). The size of the flexible substrate 4 made of polyimide was 35 mm × 16 mm × 0.08 mm, and the film thickness of the Au plating part 5 was 0.03 to 0.5 μm.

  The sheet-shaped resin compositions (1.5 mm × 15 mm) prepared in the examples and comparative examples were respectively placed between a glass substrate and a flexible substrate and heated at 100 ° C. for 10 seconds at a pressure of 1 MPa. The bonded body as shown in FIG. 2 was formed by pressing and bonding, and the formed bonded body was evaluated by the following method.

<Connection resistance value evaluation method>
The connection resistance value of each joined body was measured with a tester (Multi Instrument Co., Ltd., MCD008). The measurement results are shown in Tables 3 and 4. In the table, a connection resistance value of 3 kΩ or more and less than 6 kΩ was evaluated as “◎”, 6 kΩ or more and less than 10 kΩ was evaluated as “◯”, 10 kΩ or more and less than 30 kΩ was evaluated as “Δ”, and 30 kΩ or more was evaluated as “X”. If the connection resistance value is less than 10 kΩ, the junction state is very good and can provide stable conduction. However, if the connection resistance value is 30 kΩ or more, the connection state becomes unstable and reliability is poor. .

<High temperature and high humidity reliability test method>
After measuring the resistance value of the test piece prepared for measuring the connection resistance value, the resistance value was measured again after being held at 85 ° C. for 1000 hours under the condition of 85% humidity. The resistance values measured again (connection resistance values after the high-temperature and high-humidity reliability test) are shown in Tables 3 and 4 together with the resistance values (initial connection resistance values) before being exposed to high-temperature and high-humidity conditions. Similarly to the initial connection resistance value, the connection resistance value was evaluated as “◎” when the connection resistance value was 3 kΩ or more and less than 6 kΩ, “◯” when 6 kΩ or more and less than 10 kΩ, and “B” when 30 kΩ or more.

  The resin composition was comprehensively evaluated from the evaluation results of the initial connection resistance value and the connection resistance value after the high-temperature and high-humidity reliability test, and these are collectively shown in Tables 3 and 4 as comprehensive judgment. When at least one of the initial connection resistance value and the connection resistance value after the high-temperature and high-humidity reliability test is ×, at least one is △, and when both are ◎, both are ◎ In all other cases, it was determined as ○. Those judged as ◎ or ○ in the above comprehensive judgment can be said to be excellent in both the initial connection resistance value and the connection resistance value after the high temperature and high humidity reliability test.

  In Example 1, with respect to the total mass of the resin component, the compounding amount of the epoxy resin is 38 parts by mass, the compounding amount of the phenoxy resin is 26 parts by mass, the compounding amount of the curing agent is 36 parts by mass, and the compounding amount of the solder particles is And 7.4% by mass relative to the total mass of the resin composition (Table 1). As a result, due to the adhesion with epoxy resin, the flexibility with phenoxy resin, and the low temperature curability of the curing agent, the result of the initial connection resistance value is ◎, and the result of the connection resistance value after the high temperature and high humidity reliability test is also ◎. Both were good (Table 3).

  In Example 2, the amount of the epoxy resin is 48 parts by mass, the amount of the phenoxy resin is 20 parts by mass, the amount of the curing agent is 32 parts by mass, and the amount of the solder particles is based on the total mass of the resin component. And 7.4% by mass relative to the total mass of the resin composition (Table 1). As a result, due to the adhesion with epoxy resin, the flexibility with phenoxy resin, and the low temperature curability of the curing agent, the result of the initial connection resistance value is ◎, and the result of the connection resistance value after the high temperature and high humidity reliability test is also ◎. Both were good (Table 3).

  In Example 3, the compounding amount of the epoxy resin is 30 parts by mass, the compounding amount of the phenoxy resin is 21 parts by mass, the compounding amount of the curing agent is 48 parts by mass, and the compounding amount of the solder particles is based on the total mass of the resin component. And 7.4% by mass relative to the total mass of the resin composition (Table 1). As a result, due to the adhesion with epoxy resin, the flexibility with phenoxy resin, and the low temperature curability of the curing agent, the result of the initial connection resistance value is ◎, and the result of the connection resistance value after the high temperature and high humidity reliability test is also ◎. Both were good (Table 3).

  In Example 4, with respect to the total mass of the resin component, the amount of the epoxy resin is 40 parts by mass, the amount of the phenoxy resin is 16 parts by mass, the amount of the curing agent is 44 parts by mass, and the amount of the solder particles is And 7.4% by mass relative to the total mass of the resin composition (Table 1). As a result, due to the adhesion with epoxy resin, the flexibility with phenoxy resin, and the low temperature curability of the curing agent, the result of the initial connection resistance value is ◎, and the result of the connection resistance value after the high temperature and high humidity reliability test is also ◎. Both were good (Table 3).

  In Example 5, each component was mixed in the same amount as the resin composition of Example 1 except that the amount of solder particles was 1.0% by mass (Table 1). As a result, due to the adhesion with epoxy resin, the flexibility with phenoxy resin, and the low temperature curability of the curing agent, the result of the initial connection resistance value is ◎, and the result of the connection resistance value after the high temperature and high humidity reliability test is also ◎. Both were good (Table 3).

  In Example 6, each component was mixed in the same amount as the resin composition of Example 1 except that the amount of solder particles was 40% by mass (Table 1). As a result, due to the adhesion with epoxy resin, the flexibility with phenoxy resin, and the low temperature curability of the curing agent, the result of the initial connection resistance value is ◎, and the result of the connection resistance value after the high temperature and high humidity reliability test is also ◎. Both were good (Table 3).

  In Example 7, the compounding amount of the epoxy resin in the resin component was 15 parts by mass, and the compounding amount of the solder particles in the resin composition was 7.4% by mass (Table 1). As a result, the result of the initial connection resistance value was ◎, and the result of the connection resistance value after the high temperature and high humidity reliability test was ◯ (Table 3). This is presumably because the adhesiveness under high temperature and high humidity cannot be ensured due to the small amount of epoxy resin, and the electrical connection becomes slightly unstable.

  In Example 8, the compounding amount of the epoxy resin in the resin component was 55 parts by mass, and the compounding amount of the solder particles in the resin composition was 7.4% by mass (Table 1). As a result, the adhesion was improved by increasing the compounding amount of the epoxy resin, but because of insufficient curing, the result of the initial connection resistance value was ○, and the result of the connection resistance value after the high temperature and high humidity reliability test was ○. (Table 3).

  In Example 9, the compounding amount of the curing agent in the resin component was 15 parts by mass, and the compounding amount of the solder particles in the resin composition was 7.4% by mass (Table 1). As a result, since the curing was insufficient, the result of the initial connection resistance value was ◯, and the result of the connection resistance value after the high temperature and high humidity reliability test was ◯ (Table 3).

  In Example 10, the compounding amount of the curing agent in the resin component was 55 parts by mass, and the compounding amount of the solder particles in the resin composition was 7.4% by mass (Table 1). As a result, the result of the initial connection resistance value was ◎, but the electrical connection became unstable due to moisture absorption under high temperature and high humidity due to excessive curing agent, so the connection resistance value after the high temperature and high humidity reliability test was The result was (circle) (Table 3).

  The connection resistance values of Examples 1 to 10 described above were both below 10 kΩ before and after the high-temperature and high-humidity reliability test, and the overall judgments shown in Table 3 were all “◎” or “◯”. From the above Examples 1 to 10, it was revealed that the resin composition of the present invention can be cured at a low temperature of 120 ° C. or less and can provide a sufficient peel adhesive strength and connection resistance value.

  In Comparative Example 1, a joined body was produced using only the resin component of Example 1. Therefore, no solder particles are blended (Table 2). As a result, since it is composed only of resin components, electrical connection is not secured, and the results of the initial connection resistance value and the connection resistance value after the high-temperature and high-humidity reliability test cannot be measured (−). X (Table 4).

  In Comparative Example 2, the solder particle content in the resin composition of Comparative Example 1 was set to 50% by mass (Table 2). As a result, since the amount of solder particles is large, insulation by the resin is not ensured, and neither the initial connection resistance value nor the connection resistance value after the high-temperature, high-humidity reliability test is measurable (-), and comprehensive judgment Is x (Table 4).

  In Comparative Example 3, the compounding amount of the epoxy resin in the resin component was 10 parts by mass, and the compounding amount of the solder particles in the resin composition was 7.4% by mass (Table 2). As a result, adhesion could not be secured due to insufficient epoxy resin, the result of the initial connection resistance value was Δ, and the result of the connection resistance value after the high temperature and high humidity reliability test was also Δ (Table 4).

  In Comparative Example 4, the compounding amount of the epoxy resin in the resin component was 60 parts by mass, and the compounding amount of the solder particles in the resin composition was 7.4% by mass (Table 2). As a result, curing was insufficient due to excessive epoxy resin, and adhesion could not be secured, so the result of the initial connection resistance value was △, and the result of the connection resistance value after the high temperature and high humidity reliability test was also △ ( Table 4).

  In Comparative Example 5, the compounding amount of the curing agent in the resin component was 10 parts by mass, and the compounding amount of the solder particles in the resin composition was 7.4% by mass (Table 2). As a result, the curability of the resin component was low due to insufficient curing agent, and adhesion could not be secured, so the result of the initial connection resistance value was △, and the result of the connection resistance value after the high temperature and high humidity reliability test was × (Table 4).

  In Comparative Example 6, the compounding amount of the curing agent in the resin component was 60 parts by mass, and the compounding amount of the solder particles in the resin composition was 7.4% by mass (Table 2). As a result, the result of the initial connection resistance value was ○, but the electrical connection became particularly unstable due to moisture absorption under high temperature and high humidity due to excessive curing agent, so the connection resistance value after the high temperature and high humidity reliability test The result was Δ (Table 4).

  In the above Comparative Examples 1 to 6, the comprehensive judgments shown in Table 4 are all x or Δ, and the resin compositions obtained by kneading the components with the blending amounts of the comparative examples are all sufficiently connected. It became clear that it could not have resistance value and connection resistance value after high temperature and high humidity reliability test.

  From the above results, at least an epoxy resin that uses 1% to 40% by mass of solder particles based on the total mass of the resin composition to secure adhesiveness and resin fluidity during heating, and flexible The resin composition prepared by using a phenoxy resin that is a property-imparting material and a curing agent such as an epoxy resin amine adduct compound, an epoxy resin imidazole adduct compound, and a modified aliphatic polyamine compound is a low temperature (for example, 130 ° C. or less, It is preferably 110 ° C. or less) and can be cured in a short time (for example, 20 seconds or less, preferably about 10 seconds) to form an adhesive portion having a desired initial connection resistance and a connection resistance value after a hot and humid reliability test. I knew it could be. The use of an epoxy resin that has fluidity when heated and has a rigid skeleton can increase the conduction area through the solder during melting of the solder, and its rigidity and molecular structure. This is thought to be because the micro brown motion of the investigator segment in the three-dimensional network structure due to steric hindrance is hindered and strong adhesiveness can be secured. In addition to such characteristics, the cured product has low hygroscopicity due to its low hydroxyl group concentration, and thus the bonded portion has high temperature and high humidity reliability. Furthermore, by using a curing agent composed of a highly reactive epoxy resin adduct compound, the cured product as described above can be obtained at a low temperature and in a short time.

  The resin composition of the present invention is useful as an anisotropic conductive adhesive, and can be suitably used for, for example, a technique for connecting an electronic component and a wiring board. More specifically, an LCD module, a camera module, It can be used in various electronic devices such as a hard disk, electronic paper, touch panel, printer head, IC card, tag, and mobile phone.

DESCRIPTION OF SYMBOLS 1 Resin composition containing electroconductive particle 2 Conductive particle 3 Resin component 4 Flexible substrate 5 Au plating part 6 ITO
7 Glass substrate

Claims (6)

  A resin composition comprising conductive particles, an epoxy resin, a phenoxy resin, and a curing agent, the solder particles being included as the conductive particles, wherein the epoxy resin is a bisphenol type epoxy resin, a phenol novolac type epoxy resin, or a biphenyl type epoxy. Resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, triglycidyl isocyanurate, cyclohexane type epoxy resin and adamantane type epoxy resin, and the curing agent is an epoxy. It is at least one compound selected from the group consisting of a resin amine adduct compound, an epoxy resin imidazole adduct compound, and a modified aliphatic polyamine compound, and the content of the solder particles is based on the total mass of the resin composition When the total of the mass of the epoxy resin, the phenoxy resin and the curing agent is 100 parts by mass, the epoxy resin is included at a ratio of 12 parts by mass or more. The resin composition in which the phenoxy resin is contained in a proportion of 12 parts by mass or more and the curing agent is contained in a proportion of 12 parts by mass or more and 58 parts by mass or less.   The resin composition according to claim 1, wherein the solder particles are a Bi—In alloy.   The resin composition according to claim 2, wherein a content of Bi in the solder particles is in a range of 33% by mass to 85% by mass with respect to a total mass of the solder particles.   The said epoxy resin is contained in the ratio of 15 mass parts or more and 55 mass parts or less when the sum total of the mass of the said epoxy resin, the said phenoxy resin, and the said hardening | curing agent is 100 mass parts. The resin composition according to item.   The said phenoxy resin is contained in the ratio of 12 mass parts or more and 76 mass parts or less when the sum total of the mass of the said epoxy resin, the said phenoxy resin, and the said hardening | curing agent is 100 mass parts. The resin composition according to item.   The said hardening | curing agent is contained in the ratio of 15 mass parts or more and 55 mass parts or less, when the sum total of the mass of the said epoxy resin, the said phenoxy resin, and the said hardening | curing agent is 100 mass parts. The resin composition according to item.

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