KR101456396B1 - Anisotropic conductive adhesive film and curing agent - Google Patents

Abstract

{식 (1) 중, Q, A, R₄ 및 Y^-는 명세서에서 규정한 바와 같다.}An organic binder comprising a cationic polymerizable material; A cation generating agent represented by the formula (1) in an amount of 0.01 to 15 parts by mass based on 100 parts by mass of the organic binder containing the cationic polymerizable substance; And 0.1 to 20% by volume of the conductive particles based on the total volume of the organic binder including the cationic polymerizable material.

(In the formula (1), Q, A, R ₄ and Y ^- are as defined in the specification.}

Description

TECHNICAL FIELD [0001] The present invention relates to an anisotropic conductive adhesive film and an anisotropic conductive adhesive film.

The present invention relates to an anisotropically electroconductive adhesive film having excellent low-temperature connectivity and high reliability in peel strength in electrical connection of fine patterns, a method of manufacturing a connection structure using the anisotropic conductive adhesive film, and a curing agent.

The anisotropic conductive adhesive film is a film obtained by dispersing conductive particles in an insulating adhesive, in other words, a connection between a liquid crystal display and an IC chip or a TCP (Tape Carrier Package), a connection between an FPC (Flexible Printed Circuit) and a TCP, And is widely used for connection of a liquid crystal display and a control IC of a notebook computer or a mobile phone. In recent years, a flip chip for directly mounting an IC chip on a printed board or a flexible wiring board It is also used for mounting.

On the other hand, in recent years, in recent years, there has been an increasing demand for connection at a low temperature in order to reduce the warp caused by the temperature difference at the time of connecting and the board becoming thinner and larger.

A thermosetting type binder resin is mainly used from the viewpoint of connection reliability of the anisotropic conductive adhesive film. An epoxy resin as the curable resin, and a tertiary amine or imidazole as the anion polymerization type curing agent are mainly used as the curing agent. Further, it is known that storage stability is improved by microencapsulating tertiary amines or imidazoles. A cationic curing agent has been proposed as a curing agent capable of curing at a lower temperature than such an anion polymerization type curing agent (Patent Document 1). Further, a method of blending a stabilizer to achieve both low-temperature curing properties and storage stability (Patent Document 2) is known. In addition, a method of reducing the influence of impurity ions by using an organic boron compound as a counter ion of a cation curing agent in a cationic curable resin composition has been proposed (Patent Documents 3 and 4).

Patent Document 1: Japanese Patent No. 3907217 Patent Document 2: Japanese Patent No. 3589422 Patent Document 3: Japanese Patent Application Laid-Open No. 2008-303167 Patent Document 4: JP-A-2010-132614

However, even when these cationic curing agents are used, it is difficult to achieve both low-temperature connectivity and reliability of the peel strength, and there is a problem that the peel strength tends to deteriorate when held in a hygroscopic state.

A problem to be solved by the present invention is to provide a highly reliable anisotropic conductive adhesive film which is excellent in low-temperature connectivity and hardly deteriorates in peel strength in electrical connection between opposing wiring circuits. It is another object of the present invention to provide a cationic curing agent that combines storage stability and low temperature curability.

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted intensive studies to solve the above problems and found that an anisotropic conductive adhesive film excellent in low temperature connectivity and peel strength reliability can be obtained by the following composition.

That is, the present invention is as follows.

[1] An organic binder comprising a cationic polymerizable material;

0.01 to 15 parts by mass, relative to 100 parts by mass of the organic binder containing the cationic polymerizable substance,

(In the formula (1), Q is a substituted or unsubstituted naphthylmethyl group or a substituted or unsubstituted benzyl group, A is a phenyl group having 1 to 5 substituents, and when Q is a substituted or unsubstituted naphthylmethyl group, and to 5 of substituents meth (Hammett) is the sum of the constant -0.3~0, when Q is a substituted or unsubstituted benzyl date and the sum of the constant of the mat 1 to 5 substituents is 0~ + 0.5, R ₄ Is an alkyl group having 1 to 6 carbon atoms, and Y < ^- >

[In the formula (2), each X is independently an anion represented by fluorine, chlorine or bromine)]; And

Based on the total volume of the organic binder including the cationic polymerizable material, 0.1 to 20% by volume of the conductive particles

And an anisotropic conductive adhesive film.

[2] The anisotropic conductive adhesive film according to [1], wherein in the formula (1), Q is a substituted or unsubstituted naphthylmethyl group and the sum of Hammett constants of 1 to 5 substituents of A is -0.3 to 0.

[3] The anisotropic conductive adhesive film according to [1], wherein in the formula (1), Q is a substituted or unsubstituted benzyl group, and the sum of Hammett constants of 1 to 5 substituents of A is 0 to +0.5.

[4] In the formula (1), A is a group represented by the formula (4):

(4), R ₁ is a methyl group, an acetyl group, a phenoxycarbonyl group, a benzyloxycarbonyl group, a benzoyl group or a 9-fluorenylcarbonyl group, and R ₂ and R ₃ are each a hydrogen, a halogen, Is an alkyl group having 1 to 10 carbon atoms.

[5] The anisotropic conductive adhesive film according to [4], wherein in Formula (4), R ₁ is an acetyl group, a phenoxycarbonyl group, a benzyloxycarbonyl group or a benzoyl group, and R ₂ and R ₃ are hydrogen or a methyl group.

[6] In the formula (1), Q represents a group represented by the formula (3):

[1] to [5], wherein R ₅ is hydrogen, methyl, methoxy or halogen, a substituted or unsubstituted benzyl group, an? -Naphthylmethyl group or a? And an anisotropic conductive adhesive film.

[7] The anisotropic conductive adhesive film according to [6], wherein R ₅ in the formula (3) is hydrogen or methyl.

[8] The anisotropic conductive adhesive film according to any one of [1] to [7], wherein R ₄ in the formula (1) is a methyl group.

[9] The anisotropic conductive adhesive film according to any one of [1] to [8], wherein X in Formula (2) is fluorine.

[10] An anisotropic conductive film according to any one of [1] to [9], wherein the cationic capturing agent which reacts with the cation species generated from the cation generating agent is contained in an amount of 0.1 to 20 parts by mass based on 100 parts by mass of the cation generating agent Adhesive film.

[11] The anisotropic conductive adhesive film according to [10], wherein the cationic capturing agent is at least one selected from the group consisting of a thiourea compound, a 4-alkylthiophenol compound and a 4-hydroxyphenyl-dialkylsulfonium salt.

[12] The anisotropic conductive adhesive film according to any one of [1] to [11], wherein at least two cationic species are generated from the cation generating agent.

[13] The anisotropic conductive adhesive film according to any one of [1] to [12], wherein the organic binder comprises a resorcinol type epoxy resin.

[14] A method for manufacturing a connection structure, comprising a step of heating and pressing a pair of electronic circuit boards having corresponding electrode arrangements via an anisotropic conductive adhesive film according to any one of [1] to [13].

[15] A connection structure obtained by the manufacturing method according to [14].

[16] A compound represented by the formula (1):

(In the formula (1), Q is a substituted or unsubstituted naphthylmethyl group or a substituted or unsubstituted benzyl group, A is a phenyl group having 1 to 5 substituents, and when Q is a substituted or unsubstituted naphthylmethyl group, the sum of a constant and meth to 5 substituents are -0.3~0 and, when Q is a substituted or unsubstituted benzyl date and the sum of the mat constant of the 1 to 5 substituent is 0~ + 0.5, R ₄ is C 1 And Y < ^- > is an alkyl group of the formula (2):

[In the formula (2), each X is independently an anion represented by fluorine, chlorine or bromine.].

[17] An anisotropic conductive film comprising an organic binder having an epoxy group, a cation generator and conductive particles, wherein the epoxy reaction rate at 80 ° C for 10 seconds is less than 10% and the epoxy reaction rate at 140 ° C for 10 seconds is 80% Or more.

INDUSTRIAL APPLICABILITY The present invention has an effect that electrical connection between opposing circuits is excellent in low-temperature connection property, and deterioration of peeling strength is hard to occur. It is also possible to provide a cationic curing agent that combines storage stability and low temperature curability.

Hereinafter, the present invention will be described in detail.

An embodiment of the present invention relates to an anisotropic conductive film comprising an organic binder having an epoxy group, a cation generator and conductive particles, wherein the reaction rate of the epoxy group at 80 DEG C for 10 seconds is less than 10% Is an anisotropic conductive adhesive film having an epoxy group reaction rate of 80% or more.

The reaction rate of the epoxy group at 80 DEG C for 10 seconds is preferably less than 10%, more preferably less than 5%, and even more preferably less than 2%. When the epoxy group reaction rate is less than 10% at 80 占 폚 and 10 seconds, the storage stability is favorable and it is preferable because it is hardly affected by heat at the time of adhesion to the circuit board.

The reaction rate of the epoxy group at 140 DEG C for 10 seconds is preferably 80% or more, more preferably 85% or more, still more preferably 90% or more, particularly preferably 95% or more. When the epoxy reaction rate at 140 ° C for 10 seconds is 80% or more, the connection resistance value and the peel strength are good and the reliability after connection is also stabilized.

The epoxy group reaction rate can be measured by measuring the epoxy group absorbance ratio by the FT-IR method.

One embodiment of the present invention relates to an organic binder comprising a cationic polymerizable material; 0.01 to 15 parts by mass, relative to 100 parts by mass of the organic binder containing the cationic polymerizable substance,

(1), A is a substituted phenyl group, Q is a substituted or unsubstituted naphthylmethyl group or a substituted or unsubstituted benzyl group, R ₄ is an alkyl group having 1 to 6 carbon atoms, and Y ^- is a group represented by the formula (2) :

[In the formula (2), each X is independently an anion represented by fluorine, chlorine or bromine)]; And

Is an anisotropic conductive adhesive film comprising 0.1 to 20% by volume of conductive particles with respect to the total volume of the organic binder including the cationic polymerizable substance.

In the above formula (1), A is a phenyl group having 1 to 5 substituents, the sum of the Hammett constants of the 1 to 5 substituents is -0.3 to 0, and Q is substituted or unsubstituted naphthyl And is preferably a methyl group.

In the above formula (1), A is a phenyl group having 1 to 5 substituents, the sum of the Hammett constants of the 1 to 5 substituents is 0 to +0.5, and Q is a substituted or unsubstituted benzyl group .

The Hammett rule is an empirical rule proposed by L. P. Hammett in 1935 to quantitatively discuss the effect of substituents on the reaction or equilibrium of benzene derivatives, but this is now widely accepted. The Hammett constants obtained from the Hammett rule have σp and σm values, which can be found in many general books. See, for example, J. A. Dean, Lange ' s Handbook of Chemistry, 12th Edition, 1979 (McGraw-Hill) or in the section entitled " Chemistry ", 122, 96-103, 1979 (Nankodo), Chem. Rev., 1991, vol. 91, pp. 165-195.

Although each substituent in the present invention is limited or described by Hammett's substituent constant, it does not mean that each substituent is limited only to a substituent having a known value found in the book, It is to be understood that even when not described in the literature, substituents which fall within the range when measured based on the Hammett rule are also included.

(1), Q is a substituted or unsubstituted naphthylmethyl group, and the sum of the Hammett constants of the substituent of the phenyl group is - (-) -, the substituent is an electron donative substituent, and when the Hammett constant is negative, When 0.3 to 0, good cation generation and adequate storage stability can be achieved. The sum of the Hammett constants is more preferably -0.27 to 0, more preferably -0.25 to 0.

(1), Q is a substituted or unsubstituted benzyl group, and the sum of the Hammett constants of the substituents of the phenyl group is 0 to 4. When the Hammett constant is positive, the substituent is an electron withdrawing substituent, +0.5, good cation generation and adequate storage stability can be achieved at the same time. The sum of the Hammett constants is preferably from 0 to +0.4, more preferably from 0 to +0.35, and even more preferably from 0 to +0.3.

When the substituent represented by Q in the formula (1) is a substituted benzyl group, the sum of the Hammett constants of these substituents is preferably in the range of -0.2 to +0.2, more preferably in the range of -0.15 to +0.15 , More preferably in the range of -0.1 to +0.1. When it is in the range of -0.2 to +0.2, both cation generation property and storage stability can be achieved, which is preferable.

More specifically, the sum of the Hammett constants of the substituents of the phenyl group described in Table 2 described later is to be referred to.

One embodiment of the present invention relates to an organic binder comprising a cationic polymerizable material; 0.01 to 15 parts by mass, based on 100 parts by mass of the organic binder component containing the cationic polymerizable substance,

(In the formula (5), R ₁ represents a methyl group, an acetyl group, a phenoxycarbonyl group, a benzyloxycarbonyl group, a benzoyl group or a 9-fluorenylcarbonyl group, R ₂ and R _{3 each} represent a hydrogen, a halogen, , R ₄ is an alkyl group having 1 to 6 carbon atoms, Q is a group represented by the following formula (3):

(In the formula (3), R ₅ is hydrogen, methyl, methoxy or halogen), an α-naphthylmethyl group or a β-naphthylmethyl group, and Y ^-

[In the formula (2), each X is independently an anion represented by fluorine, chlorine or bromine)]; And 0.1 to 20% by volume of the conductive particles with respect to the total volume of the organic binder including the cationic polymerizable substance.

≪ Cation generating agent >

The cation generating agent used in the present invention may have any structure as long as it is represented by the above formula (1) or (5), but from the viewpoint of storage stability, it is preferable to generate cation species at 50 占 폚 or higher.

The cationic species generated by the thermal decomposition of the cation generating agent of the present invention may be any structure as long as the cationic polymerizable substance is sufficiently reactive with the cationic polymerizable substance. However, the cationic species may be a benzyl cation species, an α-naphthyl cation species, Cationic species are preferred. At least one of them is preferably an acyl cationic species in view of connection formability. Further, it is particularly preferable that at least two kinds of cationic species generated include acyl cationic species.

The counter anion of the cation generator may have the structure of the formula (2), but it is particularly preferable that it is a fluorine compound from the viewpoint of the impurity ion.

The content of the cation generating agent in the anisotropic conductive adhesive film of the present invention is 0.01 to 15 parts by mass, preferably 0.5 to 5 parts by mass, based on 100 parts by mass of the organic binder including the cationic polymerizable substance. When the content of the cation generating agent is less than 0.01 part by mass, curing becomes insufficient and sufficient electrical connectivity can not be obtained. When the content of the cation generating agent exceeds 15 parts by mass, the storage property is lowered.

≪ Cation capture agent >

The cationic capturing agent used in the present invention may have any structure as long as it is capable of reacting with cationic species generated by pyrolysis of the cation generating agent. However, the thiourea compound, 4-alkylthiophenol compound and 4-hydroxyphenyl- And at least one member selected from the group consisting of ammonium salts.

Specific examples of the cationic capturing agent are shown below. Examples of thiourea compounds include ethylenethiourea, N, N'-dibutylthiourea, and trimethylthiourea. Examples of the 4-alkylthiophenol compound include 4-methylthiophenol, 4-ethylthiophenol, 4-butylthiophenol and the like. Examples of the 4-hydroxyphenyl dialkylsulfonium salt include 4-hydroxyphenyldimethylsulfonium methylsulfate and 4-hydroxyphenyl-dibutylsulfonium methylsulfate.

The content of the cationic capturing agent in the anisotropic conductive adhesive film of the present invention is 0.1 to 20 parts by mass based on 100 parts by mass of the cation generating agent.

Preferably, the content of the cation scavenger is 0.5 to 10 parts by mass based on 100 parts by mass of the cation generator. When the content of the cationic capturing agent is less than 0.1 part by mass, the connection reliability is deteriorated. When the content is more than 20 parts by mass, the connectivity is deteriorated.

<Conductive Particle>

The conductive particles contained in the anisotropically conductive adhesive film of the present invention are 0.1 to 20% by volume, preferably 0.5 to 15% by volume, more preferably 1 to 10% by volume, based on the total volume of the organic binder. When the content of the conductive particles exceeds 20% by volume, the insulating property between the adjacent terminals becomes insufficient, and when the content is less than 0.1% by volume, the connectivity deteriorates. The conductive particles include metal particles such as gold, silver, copper, nickel, silver, lead, and tin, or alloys of these metals such as solder, particles of silver and copper alloy, conductive particles such as carbon, Glass, ceramics, and plastic particles are used as nuclei to cover the surface with a conductive material. Particles of metal plated with plastic particles are particularly preferable because they are excellent in connection reliability due to elastic deformation.

Examples of the plastic particles include polymers such as epoxy resin, styrene resin, silicone resin, acrylic resin, polyolefin resin, melamine resin, benzoguanamine resin, urethane resin, phenol resin, polyester resin, crosslinked divinylbenzene, NBR and SBR One or a combination of two or more kinds of nuclei can be used. These plastic particles may contain an inorganic substance such as silicon oxide. These plastics particles can be formed with Ni plating by electroless plating or the like to obtain conductive particles. It is also possible to further form a metal layer other than Ni such as gold on the Ni plating. It is also effective to coat the surface of the core with an insulating material and to allow the inner conductive particles to remove the insulating layer on the surface and make contact with the circuit to be connected when the conductive particles are used as nuclei . When such conductive particles are used, it is easy to prevent short-circuiting between adjacent terminals, and can be used also in the case of a connection circuit with a narrow terminal interval.

The particle diameter of the conductive particles is preferably 0.1 to 20 占 퐉, more preferably 1 to 10 占 퐉, and even more preferably 2 to 8 占 퐉. When the particle size is less than 0.1 탆, the connection tends to become unstable due to the fluctuation of the surface roughness of the connected terminal. When the particle diameter exceeds 20 탆, shorting between adjacent terminals tends to occur. The standard deviation of the average particle diameter of the conductive particles is preferably as small as possible, and is preferably 50% or less, more preferably 20% or less, further preferably 10% or less, particularly preferably 5% or less of the average particle diameter. The average particle diameter of the conductive particles can be measured by a known method such as a Coulter counter. In order to prevent short-circuiting between adjacent terminals, insulating particles may be used in combination within a range that does not impair the connection resistance.

Further, in order to prevent a short circuit, the conductive particles may be localized in the thickness direction of the anisotropic conductive adhesive film by a method of laminating a plurality of layers or the like.

In order to enhance storage stability, it is also effective to microencapsulate the cation generating agent in the organic binder component in advance. As a method for microencapsulation, a known method can be used, but it is preferable to use a solvent evaporation method, a spray drying method, a coacervation method, or an interfacial polymerization method.

&Lt; Organic binder containing cationic polymerizable substance >

The cationic polymerizable substance in the organic binder component is an acid-synthesized or acid-curable substance such as epoxy resin, polyvinyl ether, polystyrene and the like. The cationic polymerizable substance may be used singly or in combination of two or more.

The cationic polymerizable material is preferably an epoxy resin. The epoxy resin is preferably a compound having two or more epoxy groups in one molecule. Specifically, a compound having a glycidyl ether group, a glycidyl ester group, an alicyclic epoxy group, a compound obtained by epoxidizing a double bond in a molecule, or a compound having two or more of these substituents is more preferable. In order to improve the environmental resistance, a resorcinol type epoxy resin may also be used.

In the present invention, the organic binder component includes a binder resin and a cationic polymerizable substance, but the binder resin that can be mixed with the cationic polymerizable substance is a thermoplastic resin or a thermosetting resin reactive with an epoxy resin. The thermoplastic resin which can be mixed with the cationic polymerizable substance is a cationic polymerizable substance such as a phenoxy resin, a polyvinyl acetal resin, a polyvinyl butyral resin, an alkylated cellulose resin, a polyester resin, an acrylic resin, a urethane resin and a polyethylene terephthalate resin It is a resin with compatibility. Of these resins, a resin having a polar group such as a hydroxyl group or a carboxyl group is preferable because it is excellent in compatibility with a cationic polymerizable resin. Further, the cationic polymerizable substance is polymerized or cured by a cation to function together with the binder resin as an organic binder component.

&Lt; Other components >

The organic binder component used in the present invention may further contain other components. Other components include insulating particles, fillers, softeners, accelerators, anti-aging agents, colorants, flame retarding agents, thixotropic agents, coupling agents, and ion trap agents. In the case of solid components such as insulating particles and filler, the maximum diameter thereof is preferably less than the average particle diameter of the conductive particles. As the coupling agent, a silane coupling agent containing a ketimine group, a vinyl group, an acryl group, an amino group, an epoxy group or an isocyanate group is preferable from the viewpoint of improving the adhesion.

The content of the other components is preferably 50 parts by mass or less, more preferably 20 parts by mass or less, based on 100 parts by mass of the organic binder component.

In the case where components such as a cation generator, a cation scavenger and conductive particles are mixed with the organic binder, a solvent may be used if necessary. Examples of the solvent include methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, ethyl acetate, butyl acetate, ethylene glycol monoalkyl ether acetate and propylene glycol monoalkyl ether acetate.

<Anisotropically Conductive Adhesive Film>

The anisotropic conductive adhesive film of the present invention may be a single layer film or a film obtained by laminating a plurality of films. When a plurality of films are laminated, it is also possible to laminate films that do not contain conductive particles.

The anisotropic conductive adhesive film may be produced by previously mixing conductive particles, a cation generator, an organic binder and, if necessary, a cationic capturing agent in a solvent to prepare a coating liquid, and then applying the coating liquid on the separator by means of an applicator coating or the like , And volatilizing the solvent in an oven.

When a plurality of layers are laminated, a lamination method is preferable. In the case of laminating, there is exemplified a method of laminating using hot roll. In the case of laminating using hot roll, the temperature of the hot roll is preferably lower than the temperature at which the cation generator generates a cation species.

Examples of the separator used in the anisotropic conductive adhesive film include films such as polyethylene, polypropylene, polystyrene, polyester, PET, PEN, nylon, vinyl chloride, polyvinyl alcohol and the like. Preferable resins for the protective film include polypropylene and PET. It is preferable that the separator is subjected to surface treatment such as fluorine treatment, Si treatment, alkyd treatment or the like. The film thickness of the separator is preferably 20 占 퐉 or more and 100 占 퐉 or less.

The anisotropic conductive adhesive film of the present invention is slit to a desired width as required and wound in a reel shape.

The anisotropic conductive adhesive film of the present invention can be suitably used for connection of a liquid crystal display with TCP, TCP and FPC, connection of an FPC and a printed wiring board, or flip chip mounting in which an IC chip is directly mounted on a substrate.

&Lt; Connection method and connection structure using anisotropic conductive adhesive film >

The manufacturing method of the connection structure using the anisotropic conductive adhesive film includes a step of heating and pressing a pair of electronic circuit boards having the corresponding electrode arrangement through the anisotropic conductive adhesive film of the present invention. For example, the connection method using the anisotropic conductive adhesive film of the present invention includes a circuit board such as a glass substrate on which circuits and electrodes are formed by ITO wiring or metal wiring, and a circuit substrate on which electrodes are formed A circuit member such as an IC chip is prepared, the anisotropic conductive adhesive film of the present invention is adhered to a position where the circuit member on the circuit board is placed, and then the circuit board and the circuit member are positioned Followed by thermocompression bonding.

Upon adhering the anisotropically conductive adhesive film, the separator can be heated and pressed to peel off. The heating and pressurizing conditions are preferably, for example, heating and pressurization at a temperature of 30 DEG C or more and 80 DEG C or less and a pressure of 0.1 MPa or more and 1 MPa or less for 0.5 seconds or more and 3 seconds or less.

The thermocompression bonding at the connection is preferably performed at a temperature of not less than 120 ° C. and not more than 180 ° C. (more preferably not less than 130 ° C. and not more than 170 ° C., most preferably not less than 140 ° C. and not more than 160 ° C.) It is preferable to heat and pressurize for 3 seconds or more and 15 seconds or less (more preferably 4 seconds or more and 12 seconds or less) in a pressure range of not more than 50 MPa (more preferably not less than 0.5 MPa and not more than 40 MPa)

It is preferable that the temperature difference of the opposing connecting board is 120 占 폚 or less, more preferably 100 占 폚 or less, and even more preferably 70 占 폚 or less.

The temperature difference of each substrate can be measured by placing a thermocouple on the opposing connecting substrate.

By maintaining the temperature range, the pressure range, the bonding or thermocompression bonding time, and the temperature difference between the substrates, high connection reliability can be obtained and it is advantageous to connect the substrate with low heat resistance, It is possible to provide an electrical connection of the circuit board advantageous to shortening of the circuit board.

Example

Hereinafter, the present invention will be described in more detail by way of examples.

Example 1

30 g of an alicyclic epoxy resin composed of an ester of 1,2,3,4-butanetetracarboxylic acid and 3-cyclohexane oxide-1-methanol, 15 g of a bisphenol A type liquid epoxy resin, 3,4-epoxycyclohexylmethyl 5 g of 3,4-epoxycyclohexanecarboxylate and 50 g of a phenoxy resin having an average molecular weight of 25,000 were dissolved in a toluene-ethyl acetate mixed solvent (1: 1) to obtain a solution having a solid content of 50%.

100 parts by weight of 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium tetrakis (pentafluorophenyl) borate and 5 parts by weight of N, N'-diethylthiourea were blended and mixed with? -Butyrolactone To obtain a solution of 50 parts by mass. And the total amount of resin component 100, 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium tetrakis (pentafluorophenyl) borate and N, N'-diethylthio urea was 2 in solid mass ratio , A nickel layer having a thickness of 0.2 탆 was formed on the surface of a particle made of a benzoguanamine resin as a nucleus and a gold layer having a thickness of 0.03 탆 was formed on the outside of the nickel layer and conductive particles having an average particle size of 3.2 탆 3 volume% with respect to the volume, and dispersed to obtain a dispersion. Thereafter, the above dispersion was applied onto a polyethylene terephthalate film having a thickness of 50 占 퐉 and blow-dried at 40 占 폚 to obtain an anisotropic conductive adhesive film having a thickness of 20 占 퐉.

Example 2

Benzyl-methylsulfonium tetrakis (pentafluorophenyl) borate instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, An anisotropic conductive film was obtained in the same manner as in Example 1 except that borate was used.

Example 3

(Pentafluorophenyl) borate instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, 4-benzoyloxyphenyl- (Phenylphenyl) borate was used as the anisotropic conductive film, an anisotropic conductive film was obtained in the same manner as in Example 1.

Example 4

Instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, 4-phenoxycarbonyloxyphenyl-benzyl-methylsulfonium tetrakis (pentafluoro (Phenylphenyl) borate was used as the anisotropic conductive film, an anisotropic conductive film was obtained in the same manner as in Example 1.

Example 5

Instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzyl-methylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, 4-methoxyphenyl-β-naphthylmethylsulfonium tetrakis Fluorophenyl) borate was used and 4-hydroxyphenyldimethylsulfonium methyl sulfate was used instead of N, N'-diethyl thiourea, an anisotropic conductive film was obtained in the same manner as in Example 1.

Example 6

Except that 4-acetyloxyphenylbenzylmethylsulfonium tetrakis (pentafluorophenyl) borate was used instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzyl-methylsulfonium tetrakis (pentafluorophenyl) And 15 g of a resorcinol-type epoxy resin was used instead of 15 g of the bisphenol A-type liquid epoxy resin, an anisotropic conductive film was obtained in the same manner as in Example 1.

Example 7

Instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzyl-methylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, 4-acetyloxy 2-methylphenylbenzylmethylsulfonium tetrakis (pentafluorophenyl) ) Borate was used, an anisotropic conductive film was obtained in the same manner as in Example 1.

Comparative Example 1

Instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, p-hydroxyphenyl-benzyl-methylsulfonium tetrakis (pentafluorophenyl) An anisotropic conductive film was obtained in the same manner as in Example 1 except that borate was used and no N, N'-diethyl thiourea was added.

Comparative Example 2

(Pentafluorophenyl) borate instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, 4-methoxycarbonyloxyphenyl-benzyl-methylsulfonium tetrakis (Phenylphenyl) borate was used instead of the N, N'-diethyl thiourea, and an anisotropic conductive film was obtained in the same manner as in Example 1 except that N, N'-diethyl thiourea was not added.

Comparative Example 3

Instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium hexafluoro Anisotropic conductive film was obtained in the same manner as in Example 1, except that phosphate was used.

Comparative Example 4

Instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzyl-methylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, 4-hydroxyphenyl-a-naphthylmethyl-methylsulfonium tetrakis Pentafluorophenyl) borate was used as the anisotropic conductive film, an anisotropic conductive film was obtained in the same manner as in Example 1.

Comparative Example 5

Instead of 4-benzyloxycarbonyloxyphenyl-o-methylbenzyl-methylsulfonium tetrakis (pentafluorophenyl) borate of Example 1, 4-acetyloxyphenyl- alpha -naphthylmethyl-methylsulfonium tetrakis Pentafluorophenyl) borate was used as the anisotropic conductive film, an anisotropic conductive film was obtained in the same manner as in Example 1.

Comparative Example 6

Except that 4-cyanophenyl-benzyl-methylsulfonium tetrakis (pentafluorophenyl) borate was used in place of 4-benzyloxycarbonyloxyphenyl-o-methylbenzylmethylsulfonium tetrakis (pentafluorophenyl) An anisotropic conductive film was obtained in the same manner as in Example 1 except that the borate was used.

(Connection resistance value measurement method)

An anisotropic conductive film having a width of 2 mm was adhered on a polycarbonate film substrate (surface resistance: 200? / Sq) having a thickness of 200 占 퐉 and a thin film of indium oxide-zinc oxide (IZO) formed on the entire surface, Width compression press at 50 DEG C, 0.3 MPa and 3 seconds, and then the base film of polyethylene terephthalate is peeled off. A flexible printed wiring board (material polyimide resin, thickness 25 占 퐉) having 200 circuits made of a gold-plated copper wiring (gold-plated thickness 0.3 占 퐉) having a wiring width of 80 占 퐉, a wiring pitch of 150 占 퐉 and a thickness of 18 占 퐉 was connected After that, using a compression head having a width of 1.5 mm, press at 130 캜 for 8 seconds and 0.9 MPa for compression. After the crimping, the resistance value between the adjacent terminals is measured by a resistance meter of a divisional method to obtain a connection resistance value.

(Peel strength)

The crimped flexible printed wiring board was cut into a width of 10 mm, and a 90 ° peel strength was measured using an Instron. And a tensile speed of 50 mm / min. The measured value is taken as the peel strength. The judgment criteria are shown below.

?: Peel strength of not less than 700 g / cm

?: Peel strength of 500 g / cm or more and less than 700 g / cm

?: The peel strength is less than 500 g / cm

(Peel strength after environmental test)

The pressed printed wiring board was held for 100 hours under the environment of 85 占 폚 and 85% relative humidity, followed by 100 cycles of cycle test (-40 占 폚, 100 占 폚, 30 minutes, 1 cycle, 1 hour) And the peel strength is measured.

The evaluation criteria for environmental resistance are shown below.

α: Peel strength not less than 70% of initial value

β: The peel strength is 50% or more but less than 70% of the initial value

γ: The peel strength is less than 50% of the initial value

(Storage stability)

The anisotropic conductive film is put in a hermetically sealed container and stored at 25 DEG C for 2 weeks, and then the peel strength is measured. The criteria for the storage stability are shown below.

α: Peel strength not less than 70% of initial value

β: The peel strength is 50% or more but less than 70% of the initial value

γ: The peel strength is less than 50% of the initial value

(Measurement of reaction rate)

The epoxy group reactivity is measured by measuring the epoxy group absorbance ratio by the FT-IR method. A 2 mm wide and 20 mm long anisotropic conductive adhesive film formed on the film substrate was sandwiched between Teflon (registered trademark) tapes having a thickness of 30 탆 and pressed for 10 seconds at 0.3 MPa using a pressure heating head having a width of 2.5 mm A sample is made. FT-IR measurement is performed before and after the compression, and the epoxy reaction rate is calculated from the absorbance ratio before and after compression. The method of calculating the absorbance ratio of the epoxy group uses the methyl group absorption intensity as an internal standard and calculates the reaction rate by the following calculation formula.

Reaction rate (%) = (1 - ((a / b) / (A / B))) 100

A: Absorption strength of epoxy group before compression

B: Methyl group absorption intensity before compression

a: Absorption strength of epoxy group after compression

b: Methyl group absorption intensity after pressing

Epoxy group reaction rate at 140 占 폚 and 10 seconds

α: More than 80%

β: 50% or more and less than 80%

γ: Less than 50%

The reaction rate of the epoxy group at 80 占 폚 and 10 seconds

α: Less than 10%

β: 10% or more and less than 20%

γ: 20% or more

Table 1 shows the above results. The sum of the Hammett constants of the substituent of the phenyl group in the above formula (1) is shown in Table 2.

As is clear from Table 1, the examples using the present invention exhibit a lower deterioration in peel strength after storage and a lower deterioration in peel strength after the environmental test, as compared with the comparative example, and exhibit good connection resistance.

Claims (17)

An organic binder comprising a cationic polymerizable material;
A cation generating agent represented by the formula (1) in an amount of 0.01 to 15 parts by mass based on 100 parts by mass of the organic binder containing the cationic polymerizable substance; And
Based on the total volume of the organic binder including the cationic polymerizable material, 0.1 to 20% by volume of the conductive particles
And an anisotropic conductive adhesive film.

(In the formula (1), Q is a substituted or unsubstituted naphthylmethyl group or a substituted or unsubstituted benzyl group, A is a phenyl group having 1 to 5 substituents, and when Q is a substituted or unsubstituted naphthylmethyl group, and to 5 of substituents meth (Hammett) is the sum of the constant -0.3~0, when Q is a substituted or unsubstituted benzyl date and the sum of the constant of the mat 1 to 5 substituents is 0~ + 0.5, R ₄ Is an alkyl group having 1 to 6 carbon atoms, and Y &lt; ^- &gt;

[Wherein X in each formula (2) is independently an anion represented by fluorine, chlorine or bromine]. The anisotropic conductive adhesive film according to claim 1, wherein in the formula (1), Q is a substituted or unsubstituted naphthylmethyl group, and the sum of Hammett constants of 1 to 5 substituents of A is -0.3 to 0. The anisotropic conductive adhesive film according to claim 1, wherein in the formula (1), Q is a substituted or unsubstituted benzyl group, and the sum of Hammett constants of 1 to 5 substituents of A is 0 to +0.5. The anisotropic conductive adhesive film according to claim 1, wherein A in the formula (1) is a group represented by the formula (4).

(4), R ₁ is a methyl group, an acetyl group, a phenoxycarbonyl group, a benzyloxycarbonyl group, a benzoyl group or a 9-fluorenylcarbonyl group, and R ₂ and R ₃ are each a hydrogen, a halogen, Alkyl group. The anisotropic conductive adhesive film according to claim 4, wherein R ₁ in the formula (4) is an acetyl group, a phenoxycarbonyl group, a benzyloxycarbonyl group or a benzoyl group, and R ₂ and R ₃ are hydrogen or a methyl group. 6. The compound according to any one of claims 1 to 5, wherein Q is a substituted or unsubstituted benzyl group represented by the formula (3),? -Naphthylmethyl group or? -Naphthyl group An anisotropic conductive adhesive film which is a tilethyl group.

(In the formula (3), R ₅ is hydrogen, a methyl group, a methoxy group or a halogen.) The anisotropic conductive adhesive film according to claim 6, wherein R ₅ in the formula (3) is hydrogen or a methyl group. The anisotropic conductive adhesive film according to claim 6, wherein R ₄ in the formula (1) is a methyl group. The anisotropic conductive adhesive film according to claim 6, wherein X in the formula (2) is fluorine. The positive ion generator according to any one of claims 1 to 5, wherein an anionic conductive adhesive containing 0.1 to 20 parts by mass of a cationic capturing agent which reacts with the cation species generated from the cation generating agent with respect to 100 parts by mass of the cation generating agent film. The anisotropic conductive adhesive film according to claim 10, wherein the cationic capturing agent is at least one selected from the group consisting of a thio urea compound, a 4-alkylthiophenol compound and a 4-hydroxyphenyl-dialkylsulfonium salt. The anisotropic conductive adhesive film according to any one of claims 1 to 5, wherein at least two cationic species are generated from the cation generating agent. The anisotropic conductive adhesive film according to any one of claims 1 to 5, wherein the organic binder comprises a resorcinol type epoxy resin. Comprising the step of heating and pressing a pair of electronic circuit boards having corresponding electrode arrangements through the anisotropic conductive adhesive film according to any one of claims 1 to 5. A method for manufacturing a connection structure, A connection structure obtained by the manufacturing method according to claim 14. The cation generator represented by the formula (1).

(In the formula (1), Q is a substituted or unsubstituted naphthylmethyl group or a substituted or unsubstituted benzyl group, A is a phenyl group having 1 to 5 substituents, and when Q is a substituted or unsubstituted naphthylmethyl group, the sum of a constant and meth to 5 substituents are -0.3~0 and, when Q is a substituted or unsubstituted benzyl date and the sum of the constant of the mat 1 to 5 substituents is 0~ + 0.5, R ₄ is C 1 And Y &lt; ^- &gt; is an alkyl group of the formula (2):

[Wherein X in each formula (2) is independently an anion represented by fluorine, chlorine or bromine]. delete