KR20100073595A - Double layered anisotropic conductive adhesive - Google Patents

Abstract

PURPOSE: A double layered anisotropic conductive adhesive is provided to secure the conductive particle residue rate on a bump during an adhesion process, and to apply the adhesive to a liquid crystal display and a video display. CONSTITUTION: A double layered anisotropic conductive adhesive(10) comprises the following: an insulating layer(12) containing a thermo active epoxy hardener and an epoxy resin; and a conductive layer(14) including a conductive particle(16), a free radical generating hardener, and a radically polymerizable resin. 5~200 parts of thermo active epoxy hardener by weight is mixed with 100 parts of epoxy resin by weight. 1~50 parts of free radical generating hardener by weight is inserted for 100 parts of radically polymerizable resin by weight.

Description

Double layered anisotropic conductive adhesive

The present invention relates to an anisotropic conductive adhesive, and more particularly, to a multilayer display anisotropic conductive adhesive having a high retention of conductive particles on a bump during adhesion and excellent reworkability as a flat panel display packaging interconnect material.

Anisotropic conductive films used as flat panel display packaging materials such as liquid crystal displays (LCDs) and plasma displays (PDPs) are coated on a polyethylene terephthalate (PET) film which is formed by dispersing conductive fine particles in a thermosetting adhesive and releasing them. It means a z-axis conductive adhesive film prepared in the form of an adhesive film by the method, and has insulation in the XY plane direction. Such anisotropic conductive films have been manufactured by Hitachi Chemical Co., Ltd. (Japanese Patent Laid-Open Nos. 5-21094, 5-226020, 7-3026666, etc.), Sony Chemical Corporation (Japanese Patent Laid-Open Nos. 7-211374, 9-199206, 9-115335, etc.) over the past decade. Although many researches and commercializations have been progressed, there are still many improvements in the LCD process.

As the fine pitch and minimization of the integrated circuit (IC) bump area are progressed, the particle size of the conductive particles contained in the anisotropic conductive adhesive (anisotropic conductive film) should be reduced, and the amount of the conductive particles increased to improve conduction reliability. You have to. However, if the particle diameter of the conductive particles is made small, unevenness of the connection due to secondary aggregation or short between patterns may occur, and if the blending amount is increased, short between patterns may occur. As a countermeasure against this, attempts have been made to coat the surface of the conductive particles with an insulating layer or to multilayer the anisotropic conductive adhesive (anisotropic conductive film) to prevent the outflow of the conductive particles from the electrode. There is a problem that the residual ratio of the conductive particles on the bumps during adhesion decreases and the reworkability of the epoxy-based conductive layer is not good, and thus, when a problem occurs in the bonding process, it cannot be recycled.

Accordingly, it is an object of the present invention to provide a multilayer structure anisotropic conductive adhesive having a high retention of conductive particles on the bump during adhesion and excellent reworkability.

In order to achieve the above object, the present invention, the insulating layer comprising an epoxy resin and a heat activated epoxy curing agent; And an electrically conductive layer adhered to the insulating layer, the conductive layer including a radical polymerizable resin, a free radical generating curing agent, and conductive particles.

Here, the glass transition temperature of the insulating layer is preferably 5 to 20 ℃ lower than the glass transition temperature of the conductive layer, the melt viscosity of the insulating layer is preferably 5 to 20 times lower than the melt viscosity of the conductive layer. Do.

The anisotropically conductive adhesive of the multilayer structure according to the present invention includes a radically polymerizable resin in the conductive layer, and raises the glass transition temperature (Tg) of the conductive layer by 5 to 20 ° C. above the glass transition temperature of the insulating layer and / or the The melt viscosity of the conductive layer is increased by 5 to 20 times higher than the melt viscosity of the insulating layer. When the anisotropic conductive adhesive is used as a flat panel display packaging connection material, the residual ratio of the conductive particles on the bumps is increased, and the reworkability is improved due to the radical polymerizable resin (acrylic resin) of the conductive layer. Therefore, the anisotropic conductive adhesive of the present invention is useful for liquid crystal display devices, video display devices, and the like, which require high connection reliability.

Hereinafter, with reference to the accompanying drawings, the present invention will be described in detail.

1 is a cross-sectional view of the anisotropic conductive adhesive 10 according to an embodiment of the present invention, as shown in FIG. 1, the anisotropic conductive adhesive 10 according to the present invention includes an insulating layer 12 and It has a multilayer structure of the conductive layer 14. Here, the insulating layer 12 contains an epoxy resin and a heat-activated epoxy curing agent, and the conductive layer 14 includes a radical polymerizable resin, a free radical generating curing agent, and conductive particles 16. The insulating layer 12 and the conductive layer 14 may further include a film forming resin to help maintain the insulating layer 12 and the conductive layer 14 in the form of a film, if necessary.

The glass transition temperature of the insulating layer 12 may be 5 to 20 ° C., preferably 10 to 15 ° C. lower than the glass transition temperature of the conductive layer 14. When the glass transition temperature of the insulating layer 12 is lower than 5 ° C. compared to the glass transition temperature of the conductive layer 14, the residual ratio on the bumps of the conductive particles 16 may be lowered and exceeds 20 ° C. If low, there is a risk of problems in flowability during the bonding (bonding) process. In addition, the melt viscosity of the insulating layer 12 may be 5 to 20 times lower, preferably 5 to 15 times lower than the melt viscosity of the conductive layer 14. If the difference in the melt viscosity is out of the above range, there is a fear that the residual ratio of the conductive particles 16 (between the bump 22 and the electrode 32) on the bump 22 may be reduced. The thickness of the insulating layer 12 and the conductive layer 14 may vary depending on the height of the bump 22 and the size of the conductive particles 16, and is usually 5 to 30 μm. The thickness ratio of the said insulating layer 12 and the conductive layer 14 is 1: 0.3-3 (insulating layer: conductive layer), Preferably it is 1: 0.5-2.5, If the said ratio is less than 1: 0.3, electroconductive particle If the residual ratio on the bump 22 of (16) decreases and is 1: 3 or more, the amount of the conductive particles 16 used increases, and the raw material cost increases.

(a) epoxy resin

The epoxy resin is cured by a heat-activated epoxy curing agent to function as an insulating adhesive, and one or more epoxy resins may be used alone or in combination of two or more thereof. Although not particularly limited, the molecular weight is 200 or more, preferably Is a molecule having an aliphatic, alicyclic, aromatic cyclic or linear main chain of 250 to 5000, and a divalent or more epoxy resin having two or more glycidyl groups in one molecule can be used. Preferred examples of the epoxy resins include bisphenol A type epoxy resins having a molecular weight of 300 or more, bisphenol F type epoxy resins, bisphenol AD type epoxy resins, bisphenol S type epoxy resins, alkylene oxide adducts of the above epoxy resins, and halides (e.g., For example, tetrabromo bisphenol-type epoxy), hydrogen reactant (for example, hydrogenated bisphenol-type epoxy), cycloaliphatic epoxy resin, cycloaliphatic chain epoxy resin and their halides, hydrogen reactant, phenol novolak epoxy resin, Epoxy resins having glycidyl groups in a single backbone, epihalohydrin modified epoxy resins, acrylic modified epoxy resins, vinyl modified, such as cresol novolac epoxy resins, naphthalene epoxy resins, florene epoxy resins, and imide epoxy resins Epoxy resin, elastomer modified epoxy resin or amine modified epoxy resin, etc. As it may be used eoteonaen epoxy resin by reacting the resin or rubber in the other physical properties of the main chain. The epihalo hydrin-modified epoxy resin may be obtained by reacting epihalo hydrin with a hydroxyl group present in an epoxy resin molecule. The epoxy resins that can be modified with epihalo hydrin are bisphenol A type and bisphenol F. Type, bisphenol AD type, bisphenol S type and alkylene oxide adducts thereof, halides (e.g., tetrabromo bisphenol type epoxy), hydrogen reactants (e.g., hydrogenated bisphenol type epoxy), or alicyclic Group epoxy resins, cycloaliphatic chain epoxy resins, halides or hydrogen reactants thereof, and the like, and epihalohydrin may include epichlorohydrin, epibromohydrin, epiiod hydrin, and the like. have. The acrylic modified epoxy resin may be obtained by reacting hydroxyl groups in a molecule with an acrylic monomer, and the vinyl modified epoxy resin may be obtained by reacting hydroxyl groups in a molecule with a vinyl monomer. The elastomer used in the modification of the elastomer-modified epoxy resin may be a butadiene polymer, an acrylic polymer, a polyether rubber, a polyester rubber, a polyamide rubber, a silicone rubber, a dimer acid or a silicone resin.

(b) Heat Activated Epoxy Curing Agent

The heat-activated epoxy curing agent is stable at room temperature and does not react with the epoxy functional group and starts to react with the epoxy functional group at a predetermined temperature or higher, for example, 70 ° C. or higher, more preferably encapsulated imidazole, encapsulation One or more kinds of the amine, dicyandiamide, solid amine, solid acid anhydride, solid amide, isoisanate, solid phenol and the like can be used. Liquid epoxy curing agents cannot be used because they have high reactivity with epoxy resins at room temperature and are very low in storage stability, whereas solid epoxy curing agents have high storage stability because they have no activity up to phase changing temperature and are very active at temperatures above melting point. The low adhesion temperature and the fast curing speed is preferable because there is an advantage that the adhesion time is shortened.

The content of the heat activated epoxy curing agent is 5 to 200 parts by weight, preferably 10 to 150 parts by weight based on 100 parts by weight of the epoxy resin. If the content is less than 5 parts by weight, the curing reaction is insufficient due to the excess epoxy resin, the physical properties may be lowered. If the content is more than 200 parts by weight, the residual curing agent is left due to the excess curing agent, deteriorating the physical properties There is a fear.

(c) radically polymerizable resin

The radically polymerizable resin is a vinyl, acrylate, methacrylate, acrylic having a functional group which is cured by a free radical generating curing agent and serves as an insulating adhesive function and a matrix of conductive particles, and polymerized by radicals. A rate (methacrylate), a maleimide compound, etc. can be used individually or in mixture of 2 or more types. The said radically polymerizable resin can be used in any state of a monomer and an oligomer, and can also use together a monomer and an oligomer.

Non-limiting examples of the acrylate (methacrylate), methyl acrylate, ethyl acrylate, isopropyl acrylate, isobutyl acrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, trimethylol propane tree Acrylate, tetramethylol methanetetraacrylate, 2-hydroxy-1,3-diacryloxypropane, 2,2-bis [4- (acryloxymethoxy) phenyl] propane, 2,2-bis [ 4- (acryloxypolyethoxy) phenyl] propane, dicyclopentenyl acrylate, tricyclodecanyl acrylate, tris (acryloyloxyethyl) isocyanurate, and the like, each of which is single or two or more. It can use together and can use, and if necessary, polymerization inhibitors, such as hydroquinone and methyl ether hydroquinones, can be used suitably. Moreover, when it has a dicyclopentenyl group and / or a tricyclo decanyl group, and / or a triazine ring, since heat resistance improves, it is preferable.

Non-limiting examples of the maleimide compound include at least two maleimide groups in the molecule, for example, 1-methyl-2,4-bismaleimidebenzene, N, N'-m-phenylene Bismaleimide, N, N'-p-phenylenebismaleimide, N, N'-m-toluylenebismaleimide, N, N'-4,4-biphenylenebismaleimide, N, N ' -4,4- (3,3'-dimethyl-biphenylene) bismaleimide, N, N'-4,4- (3,3'-dimethyldiphenylmethane) bismaleimide, N, N'- 4,4- (3,3'-diethyldiphenylmethane) bismaleimide, N, N'-4,4-diphenylmethanebismaleimide, N, N'-4,4-diphenylpropanebismaleimide Mead, N, N'-4,4-diphenyletherbismaleimide, N, N'-3,3'-diphenylsulfonbismaleimide, 2,2-bis (4- (4-maleimidephenoxy ) Phenyl) propane, 2,2-bis (3-s-butyl-4-8 (4-maleimidephenoxy) phenyl) propane, 1,1-bis (4- (4-maleimidephenoxy) phenyl) Decane, 4,4'-cyclohexylidene-bis (1- (4-maleimidephenoxy) -2 -Cyclohexyl benzene, 2,2-bis (4- (4-maleimidephenoxy) phenyl) hexafluoropropane, etc. can be used.

(d) free radical generating curing agents

As the free radical (free radical) generating curing agent, peroxide compounds, azo compounds, and the like, which are decomposed by heating to generate free radicals, can be widely used, and in the case of packaging such as flat panel displays, the desired connection temperature and connection time Although it can select suitably according to the availability time etc., from the viewpoint of high reactivity and a usable time, Preferably the temperature of the 10-hour half life is 40 degreeC or more, and the temperature of 1 minute of half life is 180 degrees C or less, More preferably, The organic peroxide whose temperature of 10 hours of half life is 60 degreeC or more, and the temperature of 1 minute of half life is 170 degrees C or less can be used. When the temperature of the half-life of 10 hours is less than 40 ° C, when left at room temperature for a long time or when exposed to 40 ° C or more conditions, decomposition of the free radical generating curing agent may be started and physical properties may be degraded. When the temperature of 1 minute of said half-life exceeds 180 degreeC, there exists a possibility that a usable time may become too long and productivity may fall. Specific examples of the organic peroxide include benzoyl peroxide, diacyl peroxide, peroxydicarbonate, peroxy ester, peroxy ketal, dialkyl peroxide, hydroperoxide, and the like.

Content of the said free radical hardening | curing agent is 1-50 weight part with respect to 100 weight part of said radically polymerizable resins, Preferably it is 2-30 weight part. If the content is less than 1 part by weight, the curing reaction is insufficient due to the excess radically polymerizable resin, which may lower the physical properties. If the content exceeds 50 parts by weight, the remaining curing agent remains due to the excess amount of the curing agent. There is a risk of deterioration.

(e) conductive particles

The conductive particles 16 can be widely used conventional conductive particles 16, which can be deformed particle shape by pressing, for example, metal particles such as gold, silver, nickel, copper and / or One or more types of particles coated with metals such as gold and silver on organic or inorganic particles may be selected and used. It is preferable that the said electroconductive particle 16 exhibits electroconductivity by carrying out the insulation coating process with the insulation particle, deform | transforms the form of the electroconductive particle 16 by pressurization, and breaks the insulation film.

The size of the conductive particles 16 may be selected according to the width of the circuit and the width of the space to be applied, and may be used according to the width of the circuit to which 1 to 30㎛, preferably 2 to 20㎛ Can be. When the magnitude | size of the said electroconductive particle 16 is in the said range, it becomes excellent in electrical connection and insulation. The content of the conductive particles 16 is 1 to 90 parts by weight, preferably 1 to 50 parts by weight based on 100 parts by weight of the epoxy resin and the free radical curing agent. If the content is less than 1 part by weight, the adhesive formed from the composition of the present invention may not exhibit sufficient electrical conductivity, and if it exceeds 90 parts by weight, insulation reliability between the connection circuits is difficult to be secured and there is a fear that the anisotropic conductivity may not be exhibited.

(f) film-forming resin

The said film formation resin can use a conventional film formation resin widely, For example, a hydroxyl group or carboxylic acid containing resin, a phenoxy resin, an acrylonitrile resin, butadiene resin, an acrylic resin, a urethane resin, Polyamide resin, olefin resin, silicone resin, etc. can be used individually or in mixture of 2 or more types, respectively. Preferably, a resin having an average molecular weight of 10 to 2 million, and having a lower viscosity than the radically polymerizable resin at the same temperature, is advantageous for increasing the residual ratio on the bumps 22 of the conductive particles 16.

When the film forming resin is used, the content of the film forming resin contained in the conductive layer 14 and the insulating layer 12 is 10 to 500 weight, respectively, based on 100 parts by weight of the epoxy resin or the radical polymerizable resin. Parts, preferably 20 to 400 parts by weight. If the content is less than 10 parts by weight, the film may not be formed from the composition. If the content is more than 500 parts by weight, the curing reaction may not be sufficient and the physical properties may be lowered.

Next, the manufacturing method of the anisotropic conductive film 10 which concerns on this invention is demonstrated. The anisotropic conductive film 10 is produced by laminating the insulating layer 12 and the conductive layer 14 and bonding them by an adhesive method such as a laminating method. Here, the insulating layer 12 is formed by forming a film by applying and drying the insulating layer 12 composition consisting of the epoxy resin, a heat-activated epoxy curing agent and a film forming resin to a release film (release film), and peeling It can be obtained by separating the film formed from the film. The said conductive layer 14 apply | coats and dries the conductive layer 14 composition which consists of the said radically polymerizable resin, a free radical generating hardening | curing agent, electroconductive particle, and film formation resin to a peeling film, forms it as a film, and from a peeling film It can be obtained by separating the formed film.

When the resin component of the said insulating layer 12 and the conductive layer 14 composition is solid, with respect to 100 weight part of said compositions, it is 5 weight part or less normally, for example, it is made to melt | dissolve in the solvent of 0.01-5 weight part Use as a liquid. The conductive layer 14 and the insulating layer 12 can be manufactured. The solvent may be used a conventional solvent, for example, benzene (tozene), toluene (xylene), acetate (Acetate) solvent, ether (Ether) solvent, etc. may be used, A solvent can be used individually or in mixture of 2 or more types.

The release film may be used to prevent the insulating layer 12 and the conductive layer 14 from being contaminated from external foreign substances, and to easily peel off. For example, paper, polyolefin resin, polyethylene terephthalate ( Polyethylene terephthalate PET) resin and the like can be used, preferably a PET resin film is used. The drying is not particularly limited, but is preferably performed at a temperature of 80 to 100 ° C. for 1 to 10 minutes.

A method of using the anisotropic conductive film according to the present invention will be described with reference to FIG. 2. As shown in FIG. 2, the anisotropic conductive film 10 is positioned between the bump 22 of the integrated circuit 20 and the electrode 32 of the indium tin oxide (ITO) glass 30. Through the bonding process of heating and pressurizing, the anisotropic conductive adhesive 10 bonds the integrated circuit 20 and the indium tin oxide glass 30 so that the bumps 22 and the electrodes 32 are conductive. To be connected by the particles 16.

Hereinafter, the present invention will be described in more detail with reference to specific examples. The following examples are intended to illustrate the invention, and the invention is not limited by the following examples.

Production Example 1 Preparation of Insulation Layer

30 parts by weight of an epoxy resin (product name: Epicote-630, manufactured by JER, Japan), 18 parts by weight of a heat activated epoxy curing agent (product name: HXA-3941HP, manufactured by Asahi Kasei, Japan) and a phenoxy resin as a film forming resin. (Product Name: YP-70, Manufacture: Tokyo Chemical, Japan) After mixing 52 parts by weight, toluene was added to 5 parts by weight to prepare an insulation layer composition, and the insulation layer composition was a white polyethylene terephthalate (PET) film treated with silicon. It applied on it and dried, and obtained the film-form insulating layer of 12 micrometers thickness. The glass transition temperature (Tg) of the insulating layer was measured by a differential scanning calorimeter (DSC) manufactured by TA, and the melt viscosity was measured by using an ARES rheometer at 200 ° C, which is the temperature of the bonding process. It is shown in Table 1.

Production Example 2 Preparation of Insulation Layer

The above production was carried out except that 52 parts by weight of a phenoxy resin (product name: YP-50, manufacturer: Dongdo Chemical, Japan) was used instead of the phenoxy resin (product name: YP-70, manufactured by Dongdo Chemical, Japan) as the film forming resin. In the same manner as in Example 1, a film-like insulating layer having a thickness of 12 μm was obtained. In the same manner as in Preparation Example 1, the glass transition temperature (Tg) and the melt viscosity of the insulating layer were measured and shown in Table 1.

Production Example 3 Preparation of Insulation Layer

As the film-forming resin, 68 parts by weight of a phenoxy resin (product name: YP-50, manufacturer: Dongdo Chemical, Japan) was used instead of 52 parts by weight of a phenoxy resin (product name: YP-70, manufactured by Dongdo Chemical, Japan), and the epoxy A 12-micrometer-thick film-like insulating layer was obtained in the same manner as in Production Example 1, except that 20 parts by weight of the resin and 12 parts by weight of the thermally activated epoxy curing agent were used. In the same manner as in Preparation Example 1, the glass transition temperature (Tg) and the melt viscosity of the insulating layer were measured and shown in Table 1 below.

Production Example 4 Preparation of Conductive Layer

As the radical polymerizable resin, 30 parts by weight of bisphenoxy ethanol fluorene diacrylate (product name: BPEF-A, manufactured by Osaka Gas, Japan) and an epoxy acrylate oligomer (product name: EB-600, manufactured by SK Cytec) 15 parts by weight, 5 parts by weight of benzoyl peroxide (BPO) manufactured by Aldrich as a free radical generating curing agent, and 35 parts by weight of phenoxy resin (product name: YP-50, manufactured by Dongwha Chemical, Japan) as a film-forming resin. After mixing 15 parts by weight of the secondary and conductive particles (product name: AUL-704, manufactured by SEKISUI, Japan), 5 parts by weight of toluene is added to prepare a conductive layer composition, and the conductive layer composition is a white polyethylene tere treated with silicon. It applied on the phthalate (PET) film, it dried, and obtained the film-form conductive layer of 12 micrometers thickness. In the same manner as in Preparation Example 1, the glass transition temperature (Tg) and the melt viscosity of the conductive layer were measured and shown in Table 1 below.

Production Example 5 Preparation of Conductive Layer

Epoxy resin (product name: Epicote-630, manufacturer: JER, Japan) 26 parts by weight, heat activated epoxy curing agent (product name: HXA-3941HP, manufacturer: Asahi Kasei, Japan) 15 parts by weight, phenoxy resin as film forming resin (Product name: YP-50, manufacturer: Dongdo Chemical, Japan) 44 parts by weight and conductive particles (product name: AUL-704, manufactured by SEKISUI, Japan) were mixed, and then 5 parts by weight of toluene was added to the conductive layer composition. It prepared, and apply | coated the said conductive layer composition on the silicon-treated white polyethylene terephthalate (PET) film, and dried, and obtained the film-form conductive layer of 12 micrometers thickness. In the same manner as in Preparation Example 1, the glass transition temperature (Tg) and the melt viscosity of the conductive layer were measured and shown in Table 1 below.

Examples 1 to 3 Preparation of Anisotropic Conductive Adhesive

Each insulating layer prepared in Production Examples 1 to 3 and the conductive layer prepared in Production Example 4 were laminated to obtain an anisotropic conductive adhesive.

Comparative Example Preparation of Anisotropic Conductive Adhesive

The insulating layer manufactured in Production Example 1 and the conductive layer prepared in Production Example 5 were laminated to obtain an anisotropic conductive adhesive.

Evaluation of Physical Properties of Anisotropic Conductive Adhesive

An anisotropic conductive adhesive prepared in Examples 1 to 3 and Comparative Examples was used between an integrated circuit (IC) chip (product name: R61505V, manufactured by RENESAS) and a transparent indium tin oxide (ITO) glass having a bump area of 1,500 µm 2. 10 samples were prepared by heat-pressing at 200 degreeC for 5 second at the pressure of 50 Mpa per bump area at 200 degreeC. After fabrication, 180 bumps in the integrated circuit (IC) chip were selected and the number of conductive particles on the bumps was counted and averaged. In addition, in order to evaluate reworkability, the time taken to remove the anisotropic conductive adhesive from the sample using a knife made of acetone solvent and a soft material at room temperature was measured. The measured results are shown in Table 1 below.

product name Example 1 Example 2 Example 3 Comparative Example 3 Insulation layer YP-70 (parts by weight) 52 0 68 52 YP-50 (parts by weight) 0 52 0 0 Epicote-630 (parts by weight) 30 30 20 30 HXA-3941 (parts by weight) 18 18 12 18 Conductive layer BPEF-A (parts by weight) 30 30 30 - EB-600 (part by weight) 15 15 15 - Epicote-630 (parts by weight) - - - 26 BPO (parts by weight) 5 5 5 - HXA-3941 (parts by weight) - - - 15 YP-50 (parts by weight) 35 35 35 44 AUL-704 (part by weight) 15 15 15 15 evaluation Insulation layer Tg (℃) 80 90 80 80 Insulation layer viscosity (Pas) 1 X 10 ² 2 X 10 ² 1 X 10 ³ 1 X 10 ² Conductive Layer Tg (℃) 90 90 90 90 Conductive Layer Viscosity (Pas) 1 X 10 ³ 1 X 10 ³ 1 X 10 ³ 2 X 10 ² Conductive Particle Count (Number / Bump) 17 11 12 14 Reworkability (seconds) 60 60 60 230

From the above Table 1, in the anisotropic conductive adhesive of the present invention, when the viscosity of the insulating layer is lower than the viscosity of the conductive layer (Examples 1 and 2) and / or the glass transition temperature (Tg) of the insulating layer is the glass transition of the conductive layer. When the temperature is lower than the temperature Tg (Examples 1 and 3), the fluidity of the adhesive is improved and the number of conductive particles (residual ratio) on the bumps is 10 or more, indicating that it is useful as an anisotropic conductive adhesive, in particular, an insulating layer. It can be seen that when the glass transition temperature (Tg) is lower than the glass transition temperature (Tg) of the conductive layer and the viscosity of the insulating layer is lower than the viscosity of the conductive layer (Example 1), the effect is increased. In addition, it can be seen that the reworkability (removal time for anisotropic conductive adhesive removal) is drastically reduced in Examples 1 to 3 in which the structure of the conductive layer is acrylic resin, compared to the comparative example in which the structure of the conductive layer is epoxy resin.

1 is a cross-sectional view of the anisotropic conductive adhesive prepared in the embodiment of the present invention.

Figure 2 is a cross-sectional view after the adhesion of the anisotropic conductive adhesive and the adherend produced in the embodiment of the present invention.

Claims (5)

An insulation layer comprising an epoxy resin and a heat activated epoxy curing agent; And The anisotropically conductive adhesive agent adhere | attached to the said insulating layer and containing the electrically conductive layer containing a radically polymerizable resin, a free radical generating hardening | curing agent, and electroconductive particle. The amount of the heat-activated epoxy curing agent is 5 to 200 parts by weight, and based on 100 parts by weight of the epoxy resin, the content of the free radical generating curing agent is 100 parts by weight of the epoxy resin. 1 to 50 parts by weight, the content of the conductive particles is 1 to 90 parts by weight, anisotropic conductive adhesive. The anisotropic conductive adhesive according to claim 1, further comprising 10 to 500 parts by weight of film-forming resin, respectively, relative to 100 parts by weight of the epoxy resin and 100 parts by weight of the radically polymerizable resin. The anisotropic conductive adhesive according to claim 1, wherein the glass transition temperature of the insulating layer is 5 to 20 ° C lower than the glass transition temperature of the conductive layer. The anisotropic conductive adhesive according to claim 1, wherein a melt viscosity of the insulating layer is 5 to 20 times lower than a melt viscosity of the conductive layer.

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