KR20160006641A - Anisotropic conductive film, connecting method, and joined structure - Google Patents

Abstract

The present invention relates to an anisotropic conductive film which connects a terminal of a substrate and a terminal of an electronic component by using the anisotropic conductive film. The anisotropic conductive film comprises: a film forming resin; a curable resin; a curing agent; acrylic rubber containing a carboxyl group; and conductive particles, wherein the glass transition temperature of the acrylic rubber containing a carboxyl group is 18°C and less, and weight average molecular weight thereof is more than 75,000.

Description

TECHNICAL FIELD [0001] The present invention relates to an anisotropic conductive film, a connection method, and a bonded body,

The present invention relates to an anisotropic conductive film, a connection method, and a bonded body.

Conventionally, a tape-like connecting material (for example, anisotropic conductive film (ACF)) in which a thermosetting resin in which conductive particles are dispersed is applied to a release film is used as a means for connecting electronic components to a substrate.

The anisotropic conductive film is formed by bonding a plurality of terminals, for example, a case of connecting terminals of a flexible printed circuit board (FPC) or an IC (Integrated Circuit) chip and electrodes formed on a glass substrate of an LCD (Liquid Crystal Display) panel And is used in the case of electrically connecting together.

In recent years, there is a problem that after the connection between the substrate and the electronic component, the substrate is warped due to the thinness of the substrate connected by the anisotropic conductive film and the increase in the area of use of the substrate. When the substrate is warped, for example, color irregularity occurs in the LCD panel.

Therefore, in order to reduce warpage of the substrate, it has been proposed to alleviate the stress applied to the substrate.

(A) a thermosetting agent, (B) a thermosetting component, (C) an acrylic rubber containing a hydroxyl group, (D) an organic fine particle, and And (E) conductive particles, wherein the thermosetting component (B) contains phosphorus-containing acrylic ester and the (C) hydroxyl group-containing acrylic rubber has a weight average molecular weight of at least 1,000,000, D) organic fine particles (d1), an anisotropic conductive film containing polybutadiene fine particles has been proposed (see, for example, JP-A-2008-274019).

In addition, in the anisotropic conductive film, acrylic rubber is used for various purposes such as improvement of adhesiveness (see, for example, Japanese Patent Laid-Open Publication No. 2007-80522 and International Publication No. 2001/82363 pamphlet). Since the acrylic rubber is a rubber material, it can be expected that the stress is relaxed.

However, when a material for relieving the stress such as acrylic rubber is used for the anisotropic conductive film, there is a problem that the connection reliability is usually lowered.

It is therefore an object of the present invention to provide an anisotropic conductive film which can prevent warpage of the board and obtain excellent connection reliability, a connection method using the anisotropic conductive film, and a junction body using the anisotropic conductive film.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems and to achieve the following objects. That is, an object of the present invention is to provide an anisotropic conductive film which can prevent warpage of a substrate and obtain excellent connection reliability, a connection method using the anisotropic conductive film, and a junction body using the anisotropic conductive film.

Means for solving the above problems are as follows. In other words,

≪ 1 > An anisotropic conductive film for anisotropic conductive connection between a terminal of a substrate and a terminal of an electronic component,

A film forming resin, a curing resin, a curing agent, a carboxyl group-containing acrylic rubber, and conductive particles,

Wherein the carboxyl group-containing acrylic rubber has a glass transition temperature of 18 DEG C or lower and a weight average molecular weight of 75,000 or higher.

<2> The anisotropic conductive film according to <1>, wherein the acid value of the carboxyl group-containing acrylic rubber is 5 mgKOH / g to 40 mgKOH / g, the glass transition temperature is -30 ° C. to 15 ° C., and the weight average molecular weight is 100,000 to 900,000 to be.

<3> The method according to any one of <1> to <2>, wherein the content of the carboxyl group-containing acrylic rubber is 1% by mass to 15% by mass relative to the total amount of the film forming resin, the curing resin, the curing agent and the carboxyl group- Is an anisotropic conductive film.

&Lt; 4 &gt; A connection method for anisotropic conductive connection between a terminal of a substrate and a terminal of an electronic component,

A first disposing step of disposing an anisotropic conductive film described in any one of &lt; 1 &gt; to &lt; 3 &gt; on a terminal of the substrate;

A second disposing step of disposing the electronic part on the anisotropic conductive film so that the terminal of the electronic part is in contact with the anisotropic conductive film;

And a heating and pressing step of heating and pressing the electronic component with a heating and pressing member.

And a cured product of an anisotropic conductive film for electrically connecting the terminal of the substrate and the terminal of the electronic component interposed between the substrate and the electronic component,

Wherein the anisotropic conductive film is the anisotropic conductive film described in any one of &lt; 1 &gt; to &lt; 3 &gt;.

According to the present invention, there is provided an anisotropic conductive film which can solve the above-mentioned problems of the prior art to achieve the above object, prevent the substrate from warping and obtain excellent connection reliability, and a connection method using the anisotropic conductive film, And a junction body using the anisotropic conductive film.

Fig. 1 is a schematic view for explaining a method of measuring a deflection amount.

 (Anisotropic conductive film)

The anisotropic conductive film of the present invention contains at least a film-forming resin, a curing resin, a curing agent, a carboxyl group-containing acrylic rubber, and conductive particles, and further contains other components as necessary.

The anisotropic conductive film is an anisotropic conductive film that anisotropically conductively connects the terminals of the substrate and the terminals of the electronic component.

<Film Formation Resin>

The film-forming resin is not particularly limited and may be appropriately selected according to the purpose. Examples of the film-forming resin include phenoxy resin, unsaturated polyester resin, saturated polyester resin, urethane resin, butadiene resin, polyimide resin, polyamide resin, polyolefin resin And the like. These film-forming resins may be used alone or in combination of two or more. Of these, phenoxy resins are preferable from the viewpoints of film formability, workability, and connection reliability.

Examples of the phenoxy resin include resins synthesized from bisphenol A and epichlorohydrin.

The phenoxy resin may be appropriately synthesized, or a commercially available phenoxy resin may be used.

The content of the film-forming resin is not particularly limited and may be appropriately selected depending on the purpose.

<Curable resin>

The curable resin is not particularly limited and may be appropriately selected depending on the purpose, and examples thereof include an epoxy resin and an acrylate resin.

- Epoxy resin -

The epoxy resin is not particularly limited and may be appropriately selected depending on the purpose. Examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, modified epoxy resin and alicyclic epoxy resin have. These may be used alone or in combination of two or more.

- acrylate resin -

The acrylate resin is not particularly limited and may be appropriately selected according to the purpose. Examples of the acrylate resin include methyl acrylate, ethyl acrylate, isopropyl acrylate, isobutyl acrylate, epoxy acrylate, ethylene glycol diacrylate, diethylene 2-hydroxy-1, 3-diacryloxypropane, 2,2-bis [4- (4-hydroxyphenyl) acrylic acid] diacrylate, (Acryloxyethoxy) phenyl] propane, 2,2-bis [4- (acryloxyethoxy) phenyl] propane, dicyclopentenyl acrylate, tricyclodecanyl acrylate, tris Urea acrylate, urethane acrylate, and the like. These may be used alone or in combination of two or more.

The acrylate may be methacrylate, and these may be used singly or in combination of two or more kinds.

The content of the curable resin is not particularly limited and can be appropriately selected depending on the purpose.

<Curing agent>

The curing agent is not particularly limited and may be appropriately selected according to the purpose. Examples thereof include imidazoles, organic peroxides, anionic curing agents, cationic curing agents and the like.

The imidazoles include, for example, 2-ethyl 4-methylimidazole and the like.

Examples of the organic peroxide include lauroyl peroxide, butyl peroxide, benzyl peroxide, dilauryl peroxide, dibutyl peroxide, peroxydicarbonate, benzoyl peroxide and the like.

Examples of the anionic curing agent include organic amines and the like.

Examples of the cationic curing agent include sulfonium salts, onium salts, aluminum chelating agents and the like.

The combination of the curable resin and the curing agent is not particularly limited and may be appropriately selected according to the purpose. A combination of the epoxy resin and the cationic curing agent, and a combination of the acrylate resin and the organic peroxide are preferable.

<Carboxyl Group-Containing Acrylic Rubber>

The carboxyl group-containing acrylic rubber is not particularly limited as long as the glass transition temperature is not higher than 18 ° C and the weight average molecular weight is not lower than 75,000, and can be appropriately selected according to the purpose.

The carboxyl group-containing acrylic rubber is an acrylic rubber having a carboxyl group.

The acrylic rubber is a polymer containing a constituent unit derived from a monomer such as acrylic acid, acrylic acid ester, methacrylic acid, methacrylic acid ester, carboxyl group-containing acrylic acid ester, carboxyl group-containing methacrylic acid ester, to be.

Examples of the acrylic rubber include, for example, rubber having acrylic acid ester as a main constituent.

Examples of the copolymerizable monomers constituting the polymer include acrylic acid, methacrylic acid, butyl acrylate, butyl methacrylate, ethyl acrylate, ethyl methacrylate, methyl acrylate, methyl methacrylate, acrylonitrile and the like. .

The carboxyl group in the carboxyl group-containing acrylic rubber may be a carboxyl group derived from acrylic acid or methacrylic acid, or a carboxyl group derived from other carboxyl group-containing copolymerizable monomer. Examples of other carboxyl group-containing copolymerizable monomers include 2-acryloyloxyethylsuccinic acid, 2-methacryloyloxyethylsuccinic acid, 2-acryloyloxyethylphthalic acid, 2-methacryloyloxyethylphthalic acid, 2-acryloyloxyethylhexahydrophthalic acid, 2-methacryloyloxyethylhexahydrophthalic acid, itaconic acid, fumaric acid, and maleic acid.

The acid value of the carboxyl group-containing acrylic rubber is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 3 mgKOH / g or more, more preferably 3 mgKOH / g to 40 mgKOH / g, more preferably 5 mgKOH / g to 40 mgKOH / g is more preferable, and 5 mgKOH / g to 30 mgKOH / g is particularly preferable. When the acid value is within the above-mentioned particularly preferable range, it is advantageous in that the warp prevention of the substrate and the connection reliability can be highly compatible.

The acid value can be measured based on, for example, the Japanese Industrial Standard "JIS K 2501-2003 Petroleum products and lubricating oil-neutralization test method".

The glass transition temperature of the carboxyl group-containing acrylic rubber is not particularly limited as long as the glass transition temperature is 18 ° C or lower and can be appropriately selected according to the purpose. The glass transition temperature is preferably -40 ° C to 15 ° C, more preferably -30 ° C to 15 ° C, Deg.] C to 5 [deg.] C is particularly preferable. When the glass transition temperature is within the above-mentioned particularly preferable range, it is advantageous in that the warp prevention of the substrate and the connection reliability can be highly compatible.

The glass transition temperature can be determined, for example, by using a theoretical glass transition temperature calculation formula (FOX formula). Specifically, Tgn of the homopolymer of each monomer constituting the polymer was used according to the FOX formula (TG Fox, Bull. Am. Physics Soc., Vol. 1, No. 3, page 123 (1956) Is obtained from the following formula (1).

1 / Tg =? (Wn / Tgn) (1)

In the above formula (1), Tgn is the glass transition temperature Tg of the homopolymer of each monomer component, Wn is the weight fraction of each monomer component, and Tg is the glass transition temperature of the copolymer. The temperature in the formula (1) is the absolute temperature.

The weight average molecular weight of the carboxyl group-containing acrylic rubber is not particularly limited as long as it has a weight-average molecular weight of 75,000 or more, and can be appropriately selected according to the purpose, but is preferably 100,000 to 1,000,000, more preferably 100,000 to 900,000, and particularly preferably 700,000 to 900,000. When the weight average molecular weight is within the above-mentioned particularly preferable range, it is advantageous in that the warp prevention of the substrate and the connection reliability can be highly compatible.

The weight average molecular weight can be measured by a gel permeation chromatography (GPC) method. For the measurement, for example, Shodex GPC (manufactured by Showa Denko KK) is used. Standard polystyrene is used for calibration.

The content of the carboxyl group-containing acrylic rubber is not particularly limited and may be appropriately selected depending on the purpose. The content of the carboxyl group-containing acrylic rubber is preferably 1% by mass to 15% by mass relative to the sum of the film forming resin, the curing resin, the curing agent and the carboxyl group- , More preferably from 3% by mass to 10% by mass, and particularly preferably from 3% by mass to 5% by mass. When the content is within the above-mentioned particularly preferable range, it is advantageous in that the warp prevention of the substrate and the connection reliability can be highly compatible.

<Conductive Particle>

The conductive particles are not particularly limited and may be appropriately selected according to the purpose. Examples thereof include metal particles and metal-coated resin particles.

The metal particles are not particularly limited and may be appropriately selected according to the purpose. Examples thereof include nickel, cobalt, silver, copper, gold, palladium, and solder. These may be used alone or in combination of two or more.

Of these, nickel, silver and copper are preferable. These metal particles may be coated with gold or palladium on the surface thereof for the purpose of preventing surface oxidation. It is also possible to use a metal substrate with a metal protrusion or an insulating film coated with an organic material.

The metal-coated resin particle is not particularly limited as long as the surface of the resin particle is covered with a metal, and can be appropriately selected according to the purpose. For example, the surface of the resin particle is coated with nickel, silver, solder, copper, gold, Or a metal coated with at least one of these metals. It is also possible to use a metal substrate with a metal protrusion or an insulating film coated with an organic material. In the case of a connection considering a low resistance, particles in which the surface of the resin particle is coated with silver are preferable.

The method of coating the metal with respect to the resin particles is not particularly limited and may be appropriately selected depending on the purpose, and examples thereof include electroless plating and sputtering.

The material of the resin particles is not particularly limited and may be appropriately selected according to the purpose. Examples of the resin particles include styrene-divinylbenzene copolymer, benzoguanamine resin, crosslinked polystyrene resin, acrylic resin, styrene- have.

The conductive particles may have conductivity at the time of anisotropic conductive connection. For example, even if the surface of the metal particle is coated with an insulating coating, it is the conductive particle if the particle is deformed during the anisotropic conductive connection to expose the metal particle.

The average particle diameter of the conductive particles is not particularly limited and may be appropriately selected according to the purpose. The average particle diameter is preferably 1 탆 to 50 탆, more preferably 2 탆 to 25 탆, and particularly preferably 2 탆 to 10 탆.

The average particle diameter is an average value of the particle diameters measured for 10 conductive particles.

The particle diameter can be measured by, for example, scanning electron microscope observation.

&Lt; Other components &gt;

The other components are not particularly limited and may be appropriately selected depending on the purpose. Examples of the other components include a silane coupling agent, a filler, a softener, a curing accelerator, an antioxidant, a colorant (pigment, dye), an organic solvent, .

The content of the other components is not particularly limited and may be appropriately selected depending on the purpose.

<Substrate>

The substrate is not particularly limited as long as it is a substrate to be subjected to anisotropic conductive connection using the anisotropic conductive film and can be appropriately selected according to the purpose. For example, a glass substrate having terminals, a plastic substrate having terminals, .

Examples of the glass substrate having the terminals include ITO (Indium Tin Oxide) glass substrates, IZO (Indium Zinc Oxide) glass substrates, and other glass pattern substrates. Of these, an ITO glass substrate and an IZO glass substrate are preferable.

The material and the structure of the plastic substrate having the terminal are not particularly limited and can be appropriately selected according to the purpose. Examples thereof include a rigid substrate having terminals, and a flexible substrate having terminals.

The average thickness of the substrate is not particularly limited and may be appropriately selected according to the purpose. The thickness is preferably 0.1 mm to 1.0 mm, and more preferably 0.2 mm to 0.8 mm.

The average thickness is an average value when the thickness of any 10 points of the substrate is measured.

<Electronic parts>

The electronic component is not particularly limited and may be appropriately selected depending on the purpose as long as it is an electronic component to be subjected to anisotropic conductive connection using the anisotropic conductive film and has terminals. Examples of the electronic component include IC (Integrated Circuit), TAB Bonding tape, liquid crystal panel, and the like. Examples of the IC include an IC chip for liquid crystal display control in a flat panel display (FPD).

The shape of the electronic component is not particularly limited and can be appropriately selected according to the purpose. For example, when viewed from the top, a rectangular shape, a square shape, and the like can be given.

The combination of the substrate and the electronic component is not particularly limited and may be appropriately selected according to the purpose. For example, a combination of Flex-on-Glass (FOG), Chip-on-Glass (Chip on Glass, COG) Board and electronic components according to various mounting methods such as chip-on-flex (COF), Flex-on-Board (FLEX), and Flex-on-Flex (FLEX) And combinations thereof.

The average thickness of the anisotropic conductive film is not particularly limited and may be appropriately selected depending on the purpose. The thickness is preferably 5 占 퐉 to 100 占 퐉, more preferably 10 占 퐉 to 60 占 퐉, and particularly preferably 15 占 퐉 to 30 占 퐉.

The method for producing the anisotropic conductive film is not particularly limited and may be appropriately selected according to the purpose. For example, the anisotropic conductive film obtained by mixing the film forming resin, the curing resin, the curing agent, the carboxyl group- A method of applying the composition on a peeled polyethylene terephthalate (PET) film, and the like.

 (Connection method)

The connecting method of the present invention includes at least a first batch process, a second batch process, and a heating and pressing process, and further includes other processes as necessary.

The connection method is a method of anisotropic conductive connection of a terminal of a substrate and a terminal of an electronic part.

The substrate and the electronic part are not particularly limited and can be appropriately selected according to the purpose. For example, the substrate and the electronic part exemplified in the description of the anisotropic conductive film of the present invention are respectively included.

&Lt; First batch process &gt;

The first disposing step is not particularly limited as long as the step of disposing the anisotropic conductive film of the present invention on the terminals of the substrate can be appropriately selected according to the purpose.

<Second Arrangement Process>

The second disposing step is not particularly limited as long as it is a step of disposing the electronic part on the anisotropic conductive film and the terminal of the electronic part in contact with the anisotropic conductive film, and can be appropriately selected according to the purpose.

<Heating and pressing step>

The heating and pressing step is not particularly limited as long as it is a step of heating and pressing the electronic component with a heating and pressing member, and can be appropriately selected according to the purpose.

The heating and pressing member may be, for example, a pressing member having a heating mechanism. As a pressing member having the heating mechanism, for example, a heat tool and the like can be mentioned.

The heating temperature is not particularly limited and may be appropriately selected depending on the purpose, and is preferably 100 占 폚 to 180 占 폚.

The pressurizing pressure is not particularly limited and may be appropriately selected depending on the purpose, and is preferably from 0.5 MPa to 100 MPa.

The heating and pressurizing time is not particularly limited and may be appropriately selected depending on the purpose, and is preferably 0.5 seconds to 10 seconds.

 (Bonded body)

The junction body of the present invention has at least a substrate, a cured product of the electronic component and the anisotropic conductive film, and further includes other members as necessary.

The substrate and the electronic part are not particularly limited and can be appropriately selected according to the purpose. For example, the substrate and the electronic part exemplified in the description of the anisotropic conductive film of the present invention are respectively included.

The anisotropic conductive film is the anisotropic conductive film of the present invention.

The cured product of the anisotropic conductive film is interposed between the substrate and the electronic component to electrically connect the terminal of the substrate and the terminal of the electronic component.

The above bonded body can be produced, for example, by the above connection method of the present invention.

Example

EXAMPLES Hereinafter, examples of the present invention will be described, but the present invention is not limited to these examples at all.

(Production Examples 1 to 15)

&Lt; Carboxyl group-containing acrylic rubber No. &lt; Synthesis of 1-15>

(Meth) acrylate ester monomer having a carboxyl group such as 2- (meth) acryloyloxyethylsuccinic acid, 2- (meth) acryloyloxyethylphthalic acid and 2- (meth) acryloyloxyethylhexahydrophthalic acid, ) Acrylic acid ester and water were mixed at a predetermined mixing mass ratio so that the obtained acrylic rubber would have a desired acid value and a glass transition temperature, and the mixture was charged into a reaction vessel and thoroughly purged with nitrogen while stirring. Then, a predetermined amount of peroxide (initiator) was supplied to the mixture so that the resulting acrylic rubber had a desired weight average molecular weight, and polymerization was carried out.

The acid value, the glass transition temperature, and the weight average molecular weight of the carboxyl group-containing acrylic rubber synthesized are shown in Tables 1 to 4. The acid value, the glass transition temperature, and the weight average molecular weight were determined as follows.

<Acid value>

Acid value was measured based on the Japanese Industrial Standard "JIS K 2501-2003 Petroleum Products and Lubricating Oil - Neutralization Test Method".

<Glass transition temperature>

The glass transition temperature (Tg) was determined using the theoretical glass transition temperature equation (FOX equation).

Specifically, Tgn of a homopolymer of each monomer constituting the polymer is calculated according to FOX formula (TG Fox, Bull. Am. Physics Soc., Vol. 1, No. 3, page 123 (1956) Was obtained from the formula (1).

1 / Tg =? (Wn / Tgn) (1)

In the above formula (1), Tgn is the glass transition temperature Tg of the homopolymer of each monomer component, Wn is the weight fraction of each monomer component, and Tg is the glass transition temperature of the copolymer. The temperature in the formula (1) is the absolute temperature.

&Lt; Weight average molecular weight &

The weight average molecular weight was measured by a gel permeation chromatography (GPC) method. Shodex GPC (manufactured by Showa Denko KK) was used for the measurement. Standard polystyrene was used for calibration.

(Example 1)

&Lt; Fabrication of anisotropic conductive film &

A phenol resin (trade name: YP-50, film forming resin, manufactured by Shinnetsu Chemical Co., Ltd.), a bisphenol A type epoxy resin (trade name: EP-828, manufactured by Mitsubishi Chemical Corporation, curable resin) 403, manufactured by Shin-Etsu Chemical Co., Ltd.), a cationic curing agent (trade name: SI-60L, manufactured by Sanxin Chemical Industry Co., Ltd.) and the carboxyl group-containing acrylic rubber No. 1 were mixed in the amounts shown in Table 1 to obtain a composition. To the obtained composition, conductive particles (trade name: AUL704, manufactured by Sekisui Chemical Co., Ltd.) were dispersed to obtain an anisotropic conductive composition. The dispersion was carried out so that the particle density of the conductive particles in the resulting anisotropic conductive film was 50,000 / mm 2.

The resulting anisotropic conductive composition was coated on a polyethylene terephthalate film so as to have an average thickness of 20 占 퐉 to obtain an anisotropic conductive film.

&Lt; Preparation of the conjugate and evaluation of the conjugate &

A bonded body was produced by the following method, and the evaluation shown below was carried out. The results are shown in Table 1.

An ITO wiring board having an average thickness of 0.5 mm, in which an ITO (Indium Tin Oxide) film was patterned as a glass substrate, was used.

An IC chip (1.8 mm x 20 mm, t (thickness) = 0.5 mm, Au-plated bump 30 m x 85 m, h (height) = 15 m) was used as an electronic component.

The anisotropic conductive film was slit to a predetermined width and attached to the ITO wiring board. The IC chip was temporarily fixed thereon, and then bonded using Teflon (registered trademark) coated with an average thickness of 50 mu m as a buffer material at a bonding condition of 160 DEG C - 60 MPa - 5 sec to form a bonded body Completed.

<< Connection reliability (conduction resistance) >>

The initial resistance value of the obtained bonded body and the resistance value after a TH test (thermal humidity test) at 85 DEG C and 85% RH for 500 hours were measured by the following methods. The results are shown in Table 1.

The resistance value when a current of 1 mA was passed through a 4-terminal method was measured using a digital multimeter (product number: Digital Multimeter 7555, manufactured by Yokogawa Electric Corporation).

<< Bending amount >>

A surface-touched surface roughness tester (trade name: SE-3 H, Kosaka Laboratory Co., Ltd.) was used to measure the amount of deflection. As shown in Fig. 1, the surface of the glass substrate 1, to which the electronic component 3 is not connected by the cured product 2 of the anisotropic conductive film, The junction was placed so that the plane was horizontal. 1, the surface of the glass substrate 1 opposite to the surface to which the electronic component 3 was connected was scanned with the stylus 4 of a stylus surface roughness meter. The stylus 4 is provided on the surface of the electronic component 3 in the longitudinal direction of the electronic component 3 so as to extend from the point where one side of the electronic component 3 is located to the point where the other side opposite to the one side is located, The distance was injected. Then, the displacement in the vertical direction at the time of scanning by the stylus 4 was measured, and this was regarded as a deflection amount. The amount of warpage was measured for ten samples, and the amount of warpage was determined from the average value. The results are shown in Table 1.

Further, when the warp is convex, the amount of warp is represented by a positive number, and when warp is concave, the amount of warp is represented by a negative number.

(Examples 2 to 24 and Comparative Examples 1 to 3)

An anisotropic conductive film was produced in the same manner as in Example 1 except that the anisotropic conductive composition in Example 1 was changed to the formulations shown in Tables 1 to 4.

The obtained anisotropic conductive film was evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 4.

The relative ratios of the compounding amounts in Tables 1 to 4 coincide with the relative ratios of the contents of the respective components in the anisotropic conductive film.

The film-forming resin used in Example 22 was Epikote 1256 (manufactured by Shin-Nittsu Chemical Co., Ltd.).

The curable resin used in Example 23 is YD-128 (manufactured by Mitsubishi Chemical Corporation).

The curing agent used in Example 24 is SI-100 L (manufactured by Sanshin Chemical Industry Co., Ltd.).

In Examples 1 to 24, the deflection of the substrate was 15.0 占 퐉 or less, and the conduction resistance after 500 hours at 85 占 폚 and 85% RH was 10.0? Or less.

Particularly when the carboxyl group-containing acrylic rubber has an acid value of 5 mgKOH / g to 30 mgKOH / g, a glass transition temperature of -30 ° C to 5 ° C and a weight average molecular weight of 700,000 to 900,000 and the content of the carboxyl group- Of the total amount of the curing resin, the curing agent and the carboxyl group-containing acrylic rubber is 3% by mass to 5% by mass, the warpage of the substrate is 13.0 占 퐉 or less, and when the electric resistance after 500 hours at 85 占 폚 and 85% (For example, see Examples 2 to 6, 10, and 12).

On the other hand, in the case where the glass transition temperature of the carboxyl group-containing acrylic rubber is 20 ° C (Comparative Example 1), the case where the weight average molecular weight is 50,000 (Comparative Example 2), or when the anisotropic conductive film contains no carboxyl group- Example 3), the warpage of the substrate exceeded 15.0 占 퐉, and the continuity resistance after 500 hours at 85 占 폚 and 85% RH exceeded 10.0?, Which prevented both warping of the substrate and excellent connection reliability.

The anisotropic conductive film of the present invention can be suitably used for connection between a substrate and an electronic component in that warpage of the substrate can be prevented and excellent connection reliability can be obtained.

1 glass substrate
2 A cured product of an anisotropic conductive film
3 Electronic components
4 pointer

Claims (3)

An anisotropic conductive film for anisotropic conductive connection between a terminal of a substrate and a terminal of an electronic component,
A film forming resin, a curing resin, a curing agent, a carboxyl group-containing acrylic rubber, and conductive particles,
Wherein the carboxyl group-containing acrylic rubber has an acid value of 5 mgKOH / g to 30 mgKOH / g, a glass transition temperature of -30 to 5 ° C, a weight average molecular weight of 700,000 to 900,000,
Wherein the content of the carboxyl group-containing acrylic rubber is 3% by mass to 5% by mass relative to the total of the film-forming resin, the curing resin, the curing agent and the carboxyl group-containing acrylic rubber. A connection method for anisotropic conductive connection between a terminal of a substrate and a terminal of an electronic component,
A first disposing step of disposing the anisotropic conductive film according to claim 1 on a terminal of the substrate;
A second arranging step of disposing the electronic part on the anisotropic conductive film so that the terminal of the electronic part is in contact with the anisotropic conductive film;
And a heating and pressing step of heating and pressing the electronic component with a heating and pressing member. An electronic component having a terminal and a cured product of an anisotropic conductive film electrically connecting the terminal of the substrate and the terminal of the electronic component interposed between the substrate and the electronic component,
Characterized in that the anisotropic conductive film is the anisotropic conductive film according to any one of claims 1 to 6. The bonding body according to claim 1,

Images