WO2016182195A1 - Anisotropic conductive film and display device using same - Google Patents

Abstract

The present invention relates to an anisotropic conductive film comprising: a first layer comprising an epoxy resin and a thiol compound; and a second layer comprising an epoxy resin and an ionic curing catalyst, wherein either the first layer or the second layer further comprises conductive particles. In addition, the present invention relates to an anisotropic conductive film comprising an epoxy resin, a thiol compound, an ionic curing catalyst and conductive particles, and having a heating value change ratio, of 10% or less, in accordance with the following formula 1. [Formula 1] Heating value change ratio in (%) = [(H₀-H₁)/H₀]×100 In formula 1, H₀ represents the heating value in DSC, measured after leaving an anisotropic conductive film alone at 25°C for one day, and H₁ represents the heating value in DSC, measured after leaving the anisotropic conductive film alone at 25°C for seven days. According to one embodiment of the present invention, the anisotropic conductive film comprises a thiol compound and an ionic curing catalyst in different layers, respectively, thereby having advantages of excellent room temperature stability and of allowing ultra-low temperature curing.

Description

Anisotropic conductive film and display device using same

The present invention relates to an anisotropic conductive film and a display device using the same.

Anisotropic conductive film (ACF) generally refers to a film-like adhesive in which conductive particles are dispersed in a resin such as epoxy. The film is electrically conductive in the film thickness direction and insulated in the plane direction. It means a polymer film having anisotropy and adhesion. After placing the film between the circuits to which the anisotropic conductive film is to be connected and subjecting to heating and pressing under a certain condition, the circuit terminals are electrically connected by conductive particles, and an insulating adhesive resin is provided between adjacent electrodes. By filling, the conductive particles are present independently of each other to impart high insulation.

Generally, the anisotropic conductive film which can be connected at low temperature has mainly used the radical reactive acryl-type hardening part or the anion / cationic reactive epoxy hardening part. However, in both cases, when the connection temperature is lowered, there is a problem that the room temperature stability is lowered, and there is a problem that low temperature fast curing cannot be achieved because a latent catalyst must be used for room temperature stability (Korean Patent Application Publication No. 2007-0092639).

Accordingly, the present invention is to provide an anisotropic conductive film that can be connected at a low temperature and at the same time excellent in room temperature stability.

An object of the present invention is to provide an anisotropic conductive film that can be cured at a cryogenic temperature of 130 ° C. or lower, and is excellent in room temperature stability, and has excellent adhesion and reliability.

In one embodiment of the present invention, a first layer comprising an epoxy resin and a thiol compound; And a second layer comprising an epoxy resin and an ionic curing catalyst, wherein the anisotropic conductive film is further provided with conductive particles in either of the first layer or the second layer.

In another embodiment of the present invention, there is provided an anisotropic conductive film comprising an epoxy resin, a thiol compound, an ionic curing catalyst and conductive particles, the rate of change of the calorific value according to the following formula (1) is 10% or less.

[Equation 1]

Calorific value change rate (%) = [(H _0- H ₁ ) / H ₀ ] × 100

In the formula 1, H ₀ represents the DSC the heat generation amount measuring the anisotropic conductive film at 25 ℃ 1 day left, H ₁ represents the DSC the heat value of the anisotropic conductive film was measured at 25 ℃ and then allowed to stand 7 days.

In another embodiment of the present invention, a first connected member containing a first electrode; A second to-be-connected member containing a second electrode; And a display device connected by the anisotropic conductive film described herein, which is located between the first to-be-connected member and the second to-be-connected member to connect the first electrode and the second electrode.

Anisotropic conductive film according to an embodiment of the present invention, by including a thiol compound and an ionic curing catalyst in different layers, there is an advantage that excellent room temperature stability and cryogenic curing is possible.

1 shows a first to-be-connected member 50 including a first electrode 70, a second to-be-connected member 60 including a second electrode 80, and the first to-be-connected member and the first to-be-connected member. 2 is a cross-sectional view of a display device 30 according to an embodiment of the present invention, including an anisotropic conductive film described herein positioned between a member to be connected and connecting the first electrode and the second electrode.

Hereinafter, the present invention will be described in more detail. Content not described herein is omitted because it can be sufficiently recognized and inferred by those skilled in the art or similar fields of the present invention.

One embodiment of the present invention, the first layer comprising an epoxy resin and a thiol compound; And a second layer comprising an epoxy resin and an ionic curing catalyst, and further comprising conductive particles in any one of the first layer and the second layer.

Thiol  compound

As the thiol compound, a compound having a mercapto group (-SH) may be used.

Examples of the thiol compound include ethyl mercaptan, propyl mercaptan, benzyl mercaptan, phenylethyl mercaptan, 4-promobenzyl mercaptan, 1-phenylethyl mercaptan, n-dodecyl mercaptan and t-tert-butylbenzyl Mercaptan, 4-fluorobenzyl mercaptan, 2,4,6-trimethylbenzyl mercaptan, (4-nitrobenzyl) mercaptan, 2-trifluoromethylbenzyl mercaptan, 3,4-difluorobenzyl mer Captan, 3-fluorobenzyl mercaptan, 4-trifluoromethylbenzyl mercaptan, 4-bromo-2-fluorobenzyl mercaptan, trimethylolpropanetris-3-mercaptopropionate, pentaerythritol tetra It can be used alone or a mixture thereof selected from the group consisting of kiss-3-mercaptopropionate and dipentaerythritol hexa-3-mercaptopropionate, but is not limited thereto. Specifically, the thiol compound may be pentaerythritol tetrakis-3-mercaptopropionate.

The connection temperature or the main crimping temperature of the low temperature fast curing type anisotropic conductive film is generally 130 ° C to 160 ° C. The present invention can achieve cryogenic fast curing by using a thiol compound, can be connected or the main compression in a temperature range of less than 130 ℃, specifically 80 ℃ to 120 ℃, more specifically 90 ℃ to 115 ℃ temperature range have.

The thiol compound may be included in an amount of 10 wt% to 40 wt%, specifically 15 wt% to 35 wt%, based on the total weight of solids of the first layer. It can exhibit the cryogenic fastening and excellent adhesion and high connection reliability within the above range.

Ionic curing catalyst

The ionic curing catalyst is a curing catalyst having a cation part and an anion part can be used without limitation a compound capable of reacting with the thiol compound to initiate curing. The ion Examples of curing catalysts include imidazole ryumgye, piperidinyl nyumgye, sulfo nyumgye, ammonium and phosphonium and the cation part is at least one selected from the group consisting of nyumgye compounds, O ^-, COO ^-, S ^- group-containing compound It may be a complex compound of an anion moiety such as. Specifically, as the cationic portion, an ammonium-based, imidazolium-based, or phosphonium-based compound may be used, and more specifically, a phosphonium-based compound may be used.

Examples of the imidazolium-based compound include 1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-n-butyl-3-methylimidazolium, and the like. Examples of the nium compound include ethyl methyl piperidinium, poly-N, N'-dimethyl-3,5-methylene piperidinium, and the like. Examples of the sulfonium compound include aliphatic sulfonium and aromatic sulfonium. Can be mentioned.

In addition, examples of the ammonium-based compound include dimethyldialkylammonium, tetrabutylammonium, tetraethylammonium, tetramethylammonium, triethylbenzylammonium and the like.

Examples of the phosphonium-based compound include tributylhexylphosphonium, tripropylhexylphosphonium, tributylmethylphosphonium, tributylpentylphosphonium, tributylheptylphosphonium, tributyloctylphosphonium, tributylnonylphosphonium, Tributyldecyl phosphonium, tributyl undecyl phosphonium, tributyl dodecyl phosphonium, tributyl tetradecyl phosphonium, etc. are mentioned.

As the anion moiety component, one capable of forming a complex compound with the cation moiety may be used. For example, O ⁻ , COO ⁻ , Compounds having a functional group such as S ⁻ can be used. Examples of the anionic compound having the COO ^- group include acetates or salicylates, and examples of the anionic compound having the O ^- group include compounds having an OH group O ^- of aminophenol, phenylphenol, naphthol or cresol. Can be mentioned. Specifically, a compound in which the OH group of phenylphenol is O ⁻ may be used, and more specifically, a compound in which the OH group of 2-phenylphenol or 2,6-diphenylphenol is each O ⁻ may be used.

Examples of the anionic compound having an S ⁻ group include compounds in which the SH group of sulfatiazole is S ⁻ . In one example, tetrabutylammonium 2-phenylphenol, tetrabutylammonium 2,6-diphenylphenol, tributylhexylphosphonium 2,6-diphenylphenol and the like can be used.

The ionic curing catalyst which is a complex compound of the cation part and the anion part, unlike other curing catalysts that generate cations to promote the ring-opening reaction of the epoxy resin and advance the curing reaction, does not react with the epoxy resin and does not react with the epoxy resin by the thiol compound. It can serve to promote the curing reaction of. By placing the ionic curing catalyst and the thiol compound in a separate layer, it is possible to secure storage stability and to achieve cryogenic fast curing by using a fast curing reaction of the thiol compound.

The ionic curing catalyst may be included in an amount of 1% by weight to 20% by weight, and specifically 1% by weight to 15% by weight, based on the total weight of solids of the second layer composition.

Epoxy resin

The epoxy resin that can be used in the first layer and the second layer is not particularly limited and may be an epoxy resin commonly used in the art. In one example, the epoxy resins of the first and second layers may each be the same or different.

Examples of the epoxy resin include bisphenol epoxy compounds such as bisphenol A epoxy resin, bisphenol A epoxy acrylate resin, and bisphenol F epoxy resin; Aromatic epoxy compounds such as polyglycidyl ether epoxy resins, polyglycidyl ester epoxy resins and naphthalene epoxy resins; Alicyclic epoxy compounds; Novolak-type epoxy compounds, such as a cresol novolak-type epoxy resin and a phenol novolak-type epoxy resin; Glycidyl amine epoxy compounds; Glycidyl ester epoxy compounds; And biphenyl diglycidyl ether epoxy compounds. Specifically, the epoxy resin may be a bisphenol F type epoxy resin, a propylene oxide epoxy resin, or a naphthalene epoxy resin. The epoxy equivalent of the epoxy resin may be in the range of 300 g / eq or less, specifically 100 to 250 g / eq.

The epoxy resin may be included in an amount of 10 wt% to 40 wt%, and specifically 15 wt% to 35 wt%, based on the total weight of solids of the first layer or the second layer. Within this range, the physical properties such as adhesion, appearance, etc. may be excellent and stable after reliability.

Conductive particles

The conductive particles are not particularly limited and may be used conductive particles commonly used in the art. Non-limiting examples of the conductive particles include metal particles including Au, Ag, Ni, Cu, solder and the like; carbon; Particles coated with a metal containing Au, Ag, Ni, etc., using resins containing polyethylene, polypropylene, polyester, polystyrene, polyvinyl alcohol, and the like, and modified resins thereof as particles; Insulated electroconductive particle etc. which coat | covered the insulating particle further on it are mentioned. The size of the conductive particles may be, for example, in the range of 1 μm to 20 μm, specifically 1 μm to 10 μm, depending on the pitch of the circuit applied.

The conductive particles may be included in either the first layer or the second layer. In one example, the conductive particles may be included in the second layer including the ionic curing catalyst. Since the thiol compound tends to have a low viscosity, it may be preferable to include the conductive particles and the ionic curing catalyst in the same layer in view of the fluidity control of the conductive particles.

The conductive particles may be included in an amount of 1% by weight to 35% by weight, and specifically 1% by weight to 30% by weight, based on the total weight of solids of the first layer or the second layer. In the above range, the conductive particles can be easily pressed between the terminals to ensure stable connection reliability, and the connection resistance can be reduced by improving the conductance.

Binder resin

Each of the first layer or the second layer may further include a binder resin. Non-limiting examples of the binder resin is an olefin resin, butadiene resin, ethylene-vinylacetate copolymer, polyimide resin, polyamide resin, phenoxy resin, polymethacrylate resin, polyacrylate resin, polyurethane Resins, polyester resins, polyester urethane resins, polyvinyl butyral resins, styrene-butyrene-styrene (SBS) resins and epoxy modified materials, styrene-ethylene-butylene-styrene (SEBS) resins and their A modified body or an acrylonitrile butadiene rubber (NBR), its hydrogenated body, etc. are mentioned. These can be used individually or in mixture of 2 or more types. Specifically, the binder resin may use a phenoxy resin.

The binder resin may be included in 10% by weight to 60% by weight relative to the total weight of solids of the first layer or the second layer, specifically, may be included in 25% by weight to 55% by weight. In the above range, the flowability and adhesion of the composition for an anisotropic conductive film can be improved.

Inorganic particles

The anisotropic conductive film may further include inorganic particles in any one or more layers of the first layer and the second layer. By including an inorganic particle further, recognition property can be provided to an anisotropic conductive film and the short between electroconductive particles can be prevented.

Non-limiting examples of the inorganic particles, silica (Si, SiO ₂ ), Al ₂ O ₃ , TiO ₂ , ZnO, MgO, ZrO ₂ , PbO, Bi ₂ O ₃ , MoO ₃ , V ₂ O ₅ , Nb ₂ O ₅ , Ta ₂ O ₅ , WO ₃ or In ₂ O ₃ . Specifically, the inorganic particles may be silica. The silica may be a silica produced by a liquid phase method, such as a sol gel method, a precipitation method, or a gas phase method such as flame oxidation, a non-pulverized silica obtained by pulverizing silica gel, or fumed silica. ), Fused silica may be used, and the shape may be spherical, crushed, edgeless, or the like, and may be used alone or in combination of two or more thereof.

The inorganic particles may be included in an amount of 5 wt% to 30 wt%, and specifically 10 wt% to 25 wt%, based on the total weight of solids of the first layer or the second layer. It is excellent in the effect which prevents the outflow of the electrically-conductive particle to the space part in the said range.

Other additives

In addition, the anisotropic conductive film of the present invention may further include additives such as polymerization inhibitors, antioxidants, heat stabilizers, etc. in the first layer or the second layer in order to provide additional physical properties without impairing the basic physical properties. Can be. Specifically, an additive may be further included in the second layer. The additive is not particularly limited, but may be included in an amount of 0.01% by weight to 10% by weight based on the total weight of solids of the second layer.

As a non-limiting example, the anti-polymerization agent can be selected from the group consisting of hydroquinone, hydroquinone monomethyl ether, p-benzoquinone, phenothiazine and mixtures thereof. In addition, the antioxidant may be a phenolic or hydroxy cinnamate-based material, and specifically, tetrakis- (methylene- (3,5-di-t-butyl-4-hydroxycinnamate) methane, 3,5 -Bis (1,1-dimethylethyl) -4-hydroxy benzene propanoic acid thiol di-2,1-ethanediyl ester and the like can be used.

Manufacturing method of anisotropic conductive film

No special apparatus or equipment is required to form the anisotropic conductive film according to embodiments of the present invention. For example, a binder resin, an epoxy resin, and a thiol compound are combined in a solvent to prepare a first layer composition, which is coated on a release film to a certain thickness, for example, 1 μm to 50 μm, and then dried for a certain time. The 1st layer film can be manufactured by volatilizing a solvent. In addition, a binder resin, an epoxy resin, an ionic curing catalyst, and conductive particles may be blended in a solvent to prepare a second layer composition, and dried in the same manner as the first layer composition to prepare a second layer film.

The anisotropic conductive film may be obtained by laminating and laminating the prepared first layer and the second layer film.

Since the curing of the anisotropic conductive film is only started when the first layer containing the thiol compound is in contact with the second layer containing the ionic curing catalyst, the curing does not proceed even if left at room temperature, that is, 25 ° C. for a long time. It is characterized by excellent stability.

In another embodiment, the anisotropic conductive film is a two-layered structure in which a first layer comprising an epoxy resin and a thiol compound and a second layer comprising an epoxy resin, a cationic curing catalyst, and conductive particles are laminated or the first layer is formed on the first layer. It may be a three-layered structure in which two layers are stacked and a third layer containing no conductive particles is laminated on the second layer, and a multilayer structure in which the first layer and the second layer are laminated in four or more layers as necessary. It may be. The third layer may include an epoxy resin and a thiol compound like the first layer.

The thickness of each layer may be variously adjusted as necessary, and specifically, the thickness of the film of the first layer not containing conductive particles may be about 1.5 to 3 times thicker than the second layer film including the conductive particles. . In the case of a three-layer structure, a third layer having a thickness thinner than that of the first layer and the second layer can be laminated on the second layer.

The term “lamination” means that another layer is formed on one surface of an arbitrary layer, and may be used in combination with a coating or lamination. In the case of an anisotropic conductive film having a multilayer structure including the first layer and the second layer separately, even if the content of inorganic particles such as silica is high because the layers are separated, it does not affect the conductivity because it does not interfere with the crimping of the conductive particles. Without affecting the flowability of the composition for an anisotropic conductive film, an anisotropic conductive film with controlled fluidity can be produced.

Another embodiment of the present invention relates to an anisotropic conductive film containing an epoxy resin, a thiol compound, an ionic curing catalyst, and conductive particles, wherein the rate of change of the calorific value according to the following formula 1 is 10% or less.

[Equation 1]

Calorific value change rate (%) = [(H _0- H ₁ ) / H ₀ ] × 100

In the formula 1, H ₀ represents the DSC the heat generation amount measuring the anisotropic conductive film at 25 ℃ 1 day left, H ₁ represents the DSC the heat value of the anisotropic conductive film was measured at 25 ℃ and then allowed to stand 7 days.

In the anisotropic conductive film, the calorific value after 1 day and the calorific value change rate after 7 days may be 10% or less at 25 ° C. Specifically, the calorific value change rate may be 7% or less, and more specifically 5% or less. The change rate of the calorific value of 10% or less is related to the improvement of storage stability or storage stability of the anisotropic conductive film. Non-limiting examples of measuring the rate of change in calorific value after 25 ° C., 1 day and 7 days are as follows:

1 mg aliquot of anisotropic conductive film was measured using a differential calorimetry scanning calorimeter at 25 ° C, for example, TA company Q20 model, the initial calorific value measured after 1 day at 10 ° C / 1 min, 25 ° C (H ₀ ), and then After leaving the film at 25 ° C. for 7 days, the calorific value was measured in the same manner (H ₁ ), and the rate of change according to Equation 1 was calculated therefrom.

The anisotropic conductive film according to the above aspect comprises a first layer and a second layer, the first layer comprises an epoxy resin and a thiol compound, and the second layer comprises an epoxy resin, an ionic curing catalyst and conductive particles. It may be to include. In addition, each of the first layer and the second layer may further include a binder resin. The same epoxy resin, thiol compound, ionic curing catalyst, conductive particles, and binder resin can be used.

The anisotropic conductive film according to the present invention may have an adhesive strength of 10 MPa or more when the pressure-sensitive adhesive is pressed at 90 ° C. to 110 ° C., 1 to 5 seconds, and 5 MPa to 70 MPa. In one example, the adhesion may be 10 MPa or more and 20 MPa or less. In the case of an anisotropic conductive film having an adhesive force of less than 10 MPa, there is a problem in that the display device using the same is difficult to use for a long time, thereby shortening the life.

In the present invention, the measuring method of the adhesive force is not particularly limited, and a method commonly used in the art may be used. Non-limiting examples of methods of measuring adhesion are as follows:

The prepared anisotropic conductive film is placed between the first and second to-be-connected members and press-bonded at 60 ° C., 1 second, and 1 MPa and under conditions of 90 ° C. to 110 ° C., 1 to 5 seconds, and 5 MPa to 70 MPa. After crimping, connect. Next, the film is measured for adhesion using a peel strength meter (H5KT, Tinius Olsen, Inc.) at a peel angle of 90 ° and a peel rate of 50 mm / min.

In addition, the anisotropic conductive film, the curing rate according to the following formula 2 may be 70% or more. Specifically, it may be 80% or more.

[Equation 2]

Cure Rate (%) = [H ₃ / H ₂ ] × 100

In Equation 2, H ₂ is an anisotropic conductive film is measured by the area under the curve at 10 ℃ / min, -50 ℃ to 250 ℃ temperature range using a DSC (thermodifferential scanning calorimeter, TA instruments, Q20) One initial heating value, H ₃ represents the calorific value measured by the same method after leaving the anisotropic conductive film at 100 ℃ for 5 seconds.

In addition, the anisotropic conductive film may have a connection resistance of 0.5 Ω or less when the main compression is performed at 90 ° C to 110 ° C, 1 to 5 seconds, and 5 MPa to 70 MPa. Non-limiting examples of the connection resistance measurement method are as follows:

An anisotropic conductive film was placed between the first to-be-connected member and the second to-be-connected member and press-bonded at 60 ° C., 1 second, 1 MPa, and main compression under conditions of 90 ° C. to 110 ° C., 1 to 5 seconds, and 5 MPa to 70 MPa. Then connect. Next, several specimens are prepared using a film, and the average value is calculated by measuring the connection resistance (according to the ASTM F43-64T method) using the four-terminal measuring method.

Another embodiment of the present invention, the first to-be-connected member containing a first electrode; A second to-be-connected member containing a second electrode; And a display device connected between the first to-be-connected member and the second to-be-connected member to connect the first electrode and the second electrode by the anisotropic conductive film according to the present specification.

The first to-be-connected member may be, for example, a chip on film (COF) or a flexible printed circuit board (fPCB), and the second to-be-connected member may be, for example, a glass panel, a printed circuit board (PCB) or It may be a flexible printed circuit board (fPCB).

Referring to FIG. 1, the display device 30 will be described. The first connected member 50 including the first electrode 70 and the second connected member 60 including the second electrode 80 And mutually via an anisotropic conductive film 10 including conductive particles 3 described herein, which are located between the first to-be-connected member and the second to-be-connected member to connect the first electrode and the second electrode. Can be glued.

Hereinafter, the configuration and operation of the present invention through the preferred embodiment of the present invention will be described in more detail. However, this is presented as a preferred example of the present invention and in no sense can be construed as limiting the present invention.

Details that are not described herein will be omitted since those skilled in the art can sufficiently infer technically.

Example

Conductive layer Production Example  One

Based on the solid weight of the conductive layer composition, the binder resin portion serving as the matrix for forming the film is 30 wt% of Kupphenoxy resin (PKHH, Inchemrez, USA), and the naphthalene epoxy resin (EPICLON HP) as the curing portion accompanied by the curing reaction. 4032D, DIC Co., Epoxy Equivalent: 136 to 148 g / eq) 30 wt%, 10 wt% of cationic polymerization catalyst, electrically insulated conductive particles (AUL-704, average as filler for imparting conductive performance to anisotropic conductive films) A particle diameter of 4 µm, SEKISUI, Japan) 30% by weight was mixed and dissolved using PGMEA in an amount equivalent to that of a phenoxy resin to prepare a conductive layer composition.

After apply | coating the said conductive layer composition on a release film, the solvent was volatilized for 5 minutes in the 60 degreeC dryer, and the dried conductive layer of 9 micrometers thickness was obtained.

Non-conductive layer Production Example One

Based on the solid weight of the non-conductive layer composition, the binder resin portion is 42% by weight of phenoxy resin (PKHH, Inchemrez, USA), and the naphthalene epoxy resin (EPICLON HP 4032D, DIC, epoxy equivalent) : 136 ~ 148 g / eq) 40% by weight, 18% by weight of pentaerythritol tetrakis-3-mercaptopropionate was mixed and dissolved using PGMEA equivalent to the phenoxy resin to prepare a non-conductive layer composition. .

After applying the non-conductive layer composition on the release film, a solvent was volatilized for 5 minutes in a 60 ℃ dryer to prepare a non-conductive layer of 9 ㎛ thickness including pentaerythritol tetrakis-3-mercaptopropionate.

Example  And Comparative example  : Production of Anisotropic Conductive Film

Example  One

In the conductive layer preparation example 1, a conductive layer was prepared using tetraphenylphosphonium 2,6-dimethyl phenol as the cationic polymerization catalyst, and the non-conductive layer prepared in the non-conductive layer preparation example 1 was laminated on the conductive layer and subjected to lamination. , The anisotropic conductive film of Example 1 having a low-temperature curing type two-layer structure was prepared.

Example  2

The anisotropic conductive film of Example 2 in Example 1, except that tetrabutylammonium 2-phenylphenol was used instead of tetraphenylphosphonium 2,6-dimethyl phenol as the cationic polymerization catalyst. Was prepared.

Example  3

The anisotropic conductivity of Example 3 according to the same conditions and methods as in Example 1, except that tetraphenylphosphonium 2-phenylphenol was used instead of tetraphenylphosphonium 2,6-dimethyl phenol as the cationic polymerization catalyst. A film was prepared.

Example  4

In Example 1, the anisotropic conductive film of Example 4 was manufactured under the same conditions and methods as in Example 1, except that the weight ratio of the binder resin and the epoxy resin was adjusted from 2: 1 to 4: 1.

Example  5

In Example 1, the anisotropic conductive film of Example 5 was manufactured under the same conditions and methods as in Example 1, except that the weight ratio of the binder resin and the epoxy resin was adjusted from 2: 1 to 1: 1.

Example  6

The non-conductive layer prepared in the same manner as in the non-conductive layer Preparation Example 1 was laminated on the conductive layer manufactured by the same method except that the thickness of the conductive layer in the conductive layer preparation example 1 was 6 μm, and the two-layer structure The anisotropic conductivity of Example 6 having a low-temperature hardening type three-layer structure by laminating and laminating again the non-conductive layer prepared in the same manner as in the non-conductive layer Preparation Example 1, except that the conductive layer was manufactured to have a thickness of 3 μm. A film was prepared.

Comparative example  1: Manufacture of anisotropic conductive film

In the conductive layer preparation example 1, HX3941HP (manufactured by Asahi Kasei Co., Ltd.), which is an imidazole-based curing agent, was added instead of the cationic polymerization catalyst as the conductive layer curing agent, and the thickness thereof was changed to 6 µm. A conductive layer was prepared by the method, except that HX3941HP was added instead of pentaerythritol tetrakis-3-mercaptopropionate as a curing agent in the non-conductive layer preparation example 1, and the thickness was changed to 12 µm. A non-conductive layer prepared in the same manner as in Example 1 was laminated and laminated to prepare an anisotropic conductive film of Comparative Example 1 having a two-layer structure.

Comparative example  2: Preparation of Anisotropic Conductive Film

Based on the solid weight of the anisotropic conductive film, the binder resin portion is 25 wt% of phenoxy resin (PKHH, Inchemrez, USA), and the naphthalene epoxy resin (EPICLON HP 4032D, DIC, epoxy equivalent) : 136 ~ 148) 25% by weight, 10% by weight of pentaerythritol tetrakis-3-mercaptopropionate, 10% by weight of tetraphenylphosphonium 2,6-dimethyl phenol, for imparting conductive performance to the anisotropic conductive film As a filler, 30% by weight of insulated conductive particles (AUL-704, average particle size of 4um, SEKISUI, Japan) were mixed and dissolved using PGMEA in an amount equivalent to phenoxy resin, and then coated with a thickness of 18 μm. Then, it manufactured on the same conditions as the conductive layer manufacture example 1, and produced the anisotropic conductive film of single layer structure.

Experimental Example  : Evaluation of Physical Properties of Anisotropic Conductive Film

For the anisotropic conductive films of Examples 1 to 6 and Comparative Examples 1 to 2 prepared above, storage stability, curing rate, low temperature curability, pressure adhesion and indentation after bonding were measured, uniformity and adhesion were measured. The results are shown in Table 1 below.

Storage stability

The storage stability was measured by the rate of change of the calorific value at 25 ° C., 1 day and the calorific value at 7 day of the anisotropic conductive film, and the anisotropic prepared in each of Examples and Comparative Examples, which were left at 25 ° C. for 1 day and at 25 ° C. for 7 days. A 1 mg aliquot of the conductive film was placed in a range of 25 ° C., 10 ° C./1 min, -50 ° C. to 250 ° C. for 1 day using DSC (thermodifferential scanning calorimeter, TA instruments, Q20), and then a calorific value (H ₀ ) And the calorific value (H ₁ ) after leaving for 7 days at 25 ° C. was calculated according to Equation 1 below.

[Equation 1]

Calorific value change rate (%) = [(H _0- H ₁ ) / H ₀ ] × 100

In the formula 1, H ₀ represents the DSC the heat generation amount measuring the anisotropic conductive film at 25 ℃ 1 day left, H ₁ represents the DSC the heat value of the anisotropic conductive film was measured at 25 ℃ and then allowed to stand 7 days.

5% or less: ●, more than 5% and less than 10%: ◎, more than 10% and less than 15%: ○, more than 15%: △

Hardening rate

The anisotropic conductive films prepared in Examples and Comparative Examples were subjected to DSC (thermal differential scanning calorimeter, TA instruments, Q20) using a nitrogen gas atmosphere under nitrogen gas atmosphere at 10 ℃ / min, -50 ℃ to 250 ℃ temperature interval curve Measured by the bottom area (H ₂ ), and then leaving the film at 100 ℃ for 5 seconds and then measured the calorific value in the same way (H ₃ ) to calculate the rate of change according to Equation 2 from the results below Table 1 Shown in

[Equation 2]

Cure Rate (%) = [H ₃ / H ₂ ] × 100

●: 80% or more

◎: 70% or more and less than 80%

○: 60% or more but less than 70%

 △: less than 60%

Low temperature curability

The anisotropic conductive films prepared in Examples and Comparative Examples were placed on a glass substrate (manufactured by Neoview Kolon) with an indium tin oxide circuit having a thickness of 5000 kPa, and pressed at 1 MPa for 1 second at 60 ° C. After the pressure bonding, the release film was removed and the driver IC chip (manufacturer: Samsung LSI) having a bump area of 1430 μm was placed thereon, and then pressurized and heated at 100 ° C., 130 ° C. and 150 ° C. for 5 seconds and 50 MPa, respectively. After pressing, the case where the chip is stuck without shaking is evaluated as hardenable (○) and the case of chip falling or being pushed as non-hardenable (×) to determine whether it is hardenable.

Adhesion Bonding  after Indentation  Uniformity

The anisotropic conductive films prepared in Examples and Comparative Examples were placed on a glass substrate (manufactured by Neoview Kolon) with an indium tin oxide circuit having a thickness of 5000 kPa, and pressed at 1 MPa for 1 second at 60 ° C. After the pressing, the release film was removed and the presence or absence of bubbles between the terminals was observed under a microscope (manufacturer: Olympus). Very good image (○) when the area ratio of bubble formation in the compressed areas is 0% to 5% or less for three observation positions, good image (△) when more than 5% to less than 10%, and bad image (at 10% or more) X).

After bonding, the indentation uniformity was evaluated by pressing and heating a sample on which the driver IC chip (Samsung LSI) having a bump area of 1430 µm was pressed on the press-bonded substrate under a condition of 50 MPa for 5 seconds at 100 ° C. The uniformity of the indentation was visually observed and determined. Specifically, when the indentations on both sides of the driver IC chip are clear to the same extent as the indents of the center part, the indentation is judged to be uniform and is good (○). When it was cloudy or unclear, it was evaluated as nonuniformity (×).

Adhesion

The anisotropic conductive films prepared in Examples and Comparative Examples were placed on a glass substrate (manufactured by Neoview Kolon) having an indium tin oxide circuit having a thickness of 5000 kPa, and pressed at 1 MPa for 1 second at 60 ° C. After the pressure bonding, the release film was removed and the driver IC chip (manufacturer: Samsung LSI) having a bump area of 1430 μm was placed thereon, and then, the resultant was press-bonded under conditions of 50 MPa for 5 seconds at 100 ° C., and the maximum load: 200kgf, Test speed: 100um / sec was measured by a peel strength tester (Bond tester Dage Series-4000) a total of three or more times for each specimen to calculate their average. The measured adhesive force evaluated 10 MPa or more as ((circle)), 5 MPa or more and less than 10 MPa as ((triangle | delta)), and the impossibility of adhesive force measurement as (x).

Connection resistance

The anisotropic conductive films prepared in Examples and Comparative Examples were placed on a glass substrate (manufactured by Neoview Kolon) having an indium tin oxide circuit having a thickness of 5000 kPa, and pressed at 1 MPa for 1 second at 60 ° C. After pressing, the release film was removed and the driver IC chip (manufacturer: Samsung LSI) having a bump area of 1430 μm was placed thereon, and the specimens were pressed by pressing at 50 ° C. for 5 seconds at 100 ° C. to prepare a specimen. The resistance between 4 points was measured using. The resistance measuring instrument applies 1mA and calculates the average of the resistance by using the measured voltage. After measuring the connection resistance of the prepared specimen was evaluated as good (○) when less than 0.5Ω, poor (×) when more than 0.5Ω.

		Example 1	Example 2	Example 3	Example 4	Example 5	Example 6	Comparative Example 1	Comparative Example 2
Rate of change of heat generation (storage stability)		●	◎	●	●	●	◎	●	△
Hardening rate		●	●	●	◎	●	◎	△	●
Low temperature curability	100 ℃	○	○	○	○	○	○	×	○
	130 ℃	○	○	○	○	○	○	×	○
	150 ℃	○	○	○	○	○	○	○	○
Pressure adhesion		○	○	○	○	○	○	×	△
Indentation Uniformity		○	○	○	○	○	○	×	○
Adhesion		○	○	○	○	○	○	×	△
Connection resistance		○	○	○	○	○	○	×	×

As shown in Table 1, Examples 1 to 6, the rate of change of the calorific value was all 10% or less, it was shown that the storage stability is excellent. In addition, even when pressed at low temperature, the adhesion was excellent, and in addition, low temperature curability, curing rate, pressure adhesion, indentation uniformity and connection resistance were all good. On the other hand, Comparative Example 1 containing an imidazole-based curing catalyst in both the conductive layer and the non-conductive layer was unable to cure at low temperatures, and insufficient results were obtained in all of the pressure adhesion, indentation uniformity, adhesion, and connection resistance. The storage stability of Comparative Example 2 containing the curing catalyst in the same layer was particularly reduced.

Having described the specific parts of the present invention in detail, it will be apparent to those skilled in the art that such specific descriptions are merely preferred embodiments, and thus the scope of the present invention is not limited thereto. will be. Thus, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

Claims (15)

1. A first layer comprising an epoxy resin and a thiol compound; And

   A second layer comprising an epoxy resin and an ionic curing catalyst,

   The anisotropic conductive film which electroconductive particle is further contained in any one of the said 1st layer or the 2nd layer.
2. The anisotropic conductive film of claim 1, wherein the thiol compound is included in an amount of 10 wt% to 40 wt% based on the total weight of solids of the first layer.
3. The anisotropic conductive film of claim 1, wherein the ionic curing catalyst is included in an amount of 1 wt% to 20 wt% based on the total weight of solids of the second layer.
4. The anisotropic conductive film according to claim 1, further comprising a binder resin in each of the first layer and the second layer.
5. The thiol compound according to claim 1, wherein the thiol compound is trimethylolpropanetris-3-mercaptopropionate, pentaerythritol tetrakis-3-mercaptopropionate, dipentaerythritol hexa-3-mercaptopropionate An anisotropic conductive film which is 1 or more types chosen from the group which consists of.
6. The anisotropic conductive film according to claim 1, wherein the ionic curing catalyst is a complex compound of at least one cation part and an anion part selected from the group consisting of ammonium, phosphonium, sulfonium, imidazolium and piperidinium.
7. 7. The method of claim 6, wherein the anionic portion O ^-, COO ^-, An anisotropic conductive film having at least one functional group selected from the group consisting of S ⁻ .
8. The anisotropically conductive film of Claim 1 which is 10 Mpa or more of adhesive force with a to-be-connected member, when the anisotropically conductive film is crimped | bonded by 90 degreeC-110 degreeC, 1 to 5 second, and 5 MPa-70 MPa.
9. The anisotropic conductive film of Claim 1 whose hardening rate of following formula 2 is 70% or more.

   [Equation 2]

   Cure Rate (%) = [H ₃ / H ₂ ] × 100

   In Equation 2, H ₂ is an anisotropic conductive film is measured by the area under the curve at 10 ℃ / min, -50 ℃ to 250 ℃ temperature range using a DSC (thermodifferential scanning calorimeter, TA instruments, Q20) One initial calorific value and H ₃ represents the calorific value measured by the same method after being left at 100 ° C. for 5 seconds.
10. The anisotropic conductive film of Claim 1 whose connection resistance is 0.5 ohm or less when crimping | bonding the said anisotropic conductive film at 90 degreeC-110 degreeC, 1 to 5 second, and 5 MPa-70 MPa.
11. An anisotropic conductive film containing an epoxy resin, a thiol compound, an ionic curing catalyst, and conductive particles, wherein the rate of change of the calorific value according to the following formula 1 is 10% or less.

    [Equation 1]

    Heat generation rate change (%) = [(H ₀ -H ₁ ) / H ₀ ] × 100

    In the formula 1, H ₀ represents the DSC the heat generation amount measuring the anisotropic conductive film at 25 ℃ 1 day left, H ₁ represents the DSC the heat value of the anisotropic conductive film was measured at 25 ℃ and then allowed to stand 7 days.
12. The anisotropically conductive film of Claim 11 whose adhesive force with a to-be-connected member is 10 Mpa or more when the said anisotropic conductive film is crimped | bonded by 90 degreeC-110 degreeC, 1 to 5 second, and 5 MPa-70 MPa.
13. The method of claim 11, wherein the anisotropic conductive film comprises a first layer and a second layer,

    The first layer comprises an epoxy resin and a thiol compound,

    The second layer is an anisotropic conductive film containing an epoxy resin, an ionic curing catalyst and conductive particles.
14. The anisotropic conductive film of Claim 11 in which the said anisotropic conductive film further contains binder resin.
15. A first to-be-connected member containing a first electrode;

    A second to-be-connected member containing a second electrode; And

    The connection by the anisotropic conductive film of any one of Claims 1-14 which is located between the said 1st to-be-connected member and the said 2nd to-be-connected member, and connects the said 1st electrode and the said 2nd electrode. Display device.

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