KR20120056044A - Composition For Anisotropic Conductive Film And Anisotropic Conductive Film Using the Same - Google Patents

Abstract

PURPOSE: An aniotropically conductive film composition is provided to obtain adhesion while enduring stress generated from both ends of a connection substrate under compression due to heat and pressure. CONSTITUTION: An aniotropically conductive film composition has an elastic modulus of 4,000-10,000 MPa at 50°C after curing, and a glass transition temperature(Tg) of 110-150 °C after curing. The aniotropically conductive film composition comprises an acrylate-modified urethane resin, a diene-based rubber, an elastically reinforced resin, a radically polymerizable material, a polymerization initiator, and conductive particles. The elastically reinforced resin is one or more selected from a cellulose based resin and a styrene based resin. The elastically reinforced resin comprises 20-50 weight% of the cellulose based resin and 50-80 weight% of the styrene based resin.

Description

Composition For Anisotropic Conductive Film And Anisotropic Conductive Film Using The Same {Composition For Anisotropic Conductive Film And Anisotropic Conductive Film Using the Same}

The present invention relates to a composition for an anisotropic conductive film and an anisotropic conductive film using the same. More specifically, the present invention provides a composition for anisotropic conductive films that can withstand the stress generated at both ends of the connection substrate when the elasticity and glass transition temperature of the anisotropic conductive film after curing to a specific range and the pressure caused by heat and pressure and anisotropic using the same It relates to a conductive film.

Anisotropic conductive films are used to electrically connect small electrical components such as semiconductor devices to substrates or to electrically connect between substrates in the manufacture of electronic products such as liquid crystal displays, personal computers, portable communication devices, and the like.

In recent years, as the panel becomes larger and the wiring becomes finer, the connection board becomes thinner and longer, which causes severe shrinkage / expansion of the connection board during crimping due to heat and pressure. The stress becomes large. As the stress increases in this way, internal breakage occurs, which causes adhesion failure.

FIG. 1 is a photograph showing that voids are formed due to internal breakdown caused by stress generated by shrinkage / expansion of a connection substrate during compression using heat and pressure using a conventional adhesive composition.

JP3342703 discloses an anisotropic conductive adhesive material having a modulus of elasticity of 100 to 2000 MPa at 40 ° C. after adhesion in a heat adhesive adhesive that electrically connects a circuit electrode by heat and pressure. However, the patent is also insufficient to solve the problem of poor adhesion due to the internal breakdown caused by stress during the compression by heat and pressure.

In order not to be destroyed by the stress caused by shrinkage / expansion of the connecting substrate during the compression by heat and pressure, the elastic modulus of the anisotropic conductive film after curing should be high, and the glass transition temperature must be high so that the stress expression by the elastic modulus of the anisotropic conductive film after curing This is facilitated. This is because the stress must be greater than the stress due to shrinkage / expansion of the connecting substrate so that internal breakage does not occur and adhesion can be maintained.

In general, the stress is very small because the elastic modulus is low in the rubbery state above the glass transition temperature, but the stress increases as the elastic modulus increases below the glass transition temperature. If the glass transition temperature of the composition is high, but the elastic modulus is low after curing, a problem may occur because the stress is small, and if the glass transition temperature is low, the fracture occurs before the stress due to the increase of the elastic modulus is expressed. The problem cannot be solved.

In addition, when the elastic modulus is high, it is difficult to express the adhesive force due to the ACF characteristics, and thus, it is necessary to adjust the elastic modulus after curing. Accordingly, in order to be able to withstand the stress generated at both ends of the connecting substrate during the compression by heat and pressure, and to develop adhesive force, an anisotropic conductive film satisfying the two characteristics is required.

An object of the present invention is to provide an anisotropic conductive film composition and an anisotropic conductive film using the same that can withstand the stress generated at both ends of the connection substrate when the compression by heat and pressure.

Another object of the present invention is to provide an anisotropic conductive film composition having excellent connection reliability and an anisotropic conductive film using the same.

One aspect of the present invention relates to a composition for an anisotropic conductive film. The composition has an elastic modulus of 4000 MPa to 10000 MPa at 50 ° C. after curing, and a glass transition temperature (Tg) of 110 ° C. to 150 ° C. after curing.

In an embodiment, the composition for the anisotropic conductive film may include an acrylate-modified urethane resin, a diene rubber resin, an elastic reinforcing resin, a radical polymerizable material, a polymerization initiator, and conductive particles.

In an embodiment, the composition for the anisotropic conductive film is 30 to 70% by weight of the acrylate-modified urethane resin, 5 to 25% by weight of the diene rubber resin, 5 to 40% by weight of the elastic reinforcing resin, 10 to 30% by weight of the radical polymerizable material , 1 to 5% by weight of a polymerization initiator, and 1 to 10% by weight of conductive particles.

The elastic reinforcing resin may be at least one of cellulose resin and styrene resin.

In one embodiment, the elastic reinforcing resin may include 20 to 50% by weight of cellulose-based resin and 50 to 80% by weight of styrene-based resin.

In another embodiment the composition may further comprise more than 0% to 15% by weight of the acrylic copolymer or styrene resin.

The acrylate-modified urethane resin may have a hydroxyl group / isocyanate group (NCO) molar ratio of 0.5 to 1.0 and a polyol content of up to 70%.

In a specific embodiment, the diene rubber resin is acrylonitrile-butadiene copolymer, styrene butadiene copolymer, (meth) acrylate-butadiene copolymer, (meth) acrylate-acrylonitrile-butadiene-styrene copolymer, carboxyl group modification Acrylonitrile-butadiene rubber and the like can be used.

The cellulose-based resin may have a weight average molecular weight of 12,000 to 80,000 g / mol.

The radically polymerizable substance may be urethane-based (meth) acrylate, epoxy-based (meth) acrylate, polyester-based (meth) acrylate, fluorine-based (meth) acrylate, fluorene-based (meth) acrylate, or silicone-based (meth) Acrylate, phosphate (meth) acrylate, maleimide modified (meth) acrylate, acrylate (methacrylate), (meth) acrylate monomer and the like can be used.

The polymerization initiator may be used ketone peroxide, peroxy ketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxy ester, peroxy carbonate and the like.

The conductive particles may be metal particles including at least one of Au, Ag, Ni, Cu, Pd, Al, Cr, Sn, Ti, and Pb; Carbon particles; Particles coated with the metals of particles comprising resins containing at least one of benzoguanamine, polyolefins, polyesters, polystyrenes and polyvinyl alcohols or modified resins thereof; And particles insulated from the coated particles may be used.

The styrene resin may have a weight average molecular weight of 90,000 to 150,000 g / mol.

The acrylic copolymer may have a weight average molecular weight of 90,000 to 120,000 g / mol, and a glass transition temperature of 50 ° C. to 120 ° C.

The acrylic copolymer may have an acid value of 1 to 100 mg KOH / g.

The present invention also provides an anisotropic conductive film formed by the composition.

The present invention provides an anisotropic conductive film composition and an anisotropic conductive film composition using the same, which can express adhesive force while being able to withstand the stresses generated at both ends of the connecting substrate when pressed by heat and pressure. Have

1 is a photograph showing that voids are formed due to internal breakdown using a conventional adhesive composition.
2 is a photograph showing the adhesion state in the Examples and Comparative Examples.

Contents mentioned below are based on solids, unless otherwise specified. Acrylic resins also include both acrylate and methacrylate resins.

The composition for anisotropic conductive films of the present invention may have an elastic modulus of 4000 MPa to 10000 MPa, preferably 4500 MPa to 8500 MPa, and more preferably 5000 MPa to 8000 MPa at 50 ° C. after curing. In the elastic modulus range, it is not destroyed by stress caused by shrinkage / expansion of the connecting substrate during compression by heat and pressure.

In addition, the composition is characterized in that the glass transition temperature (Tg) after curing is 110 ℃ ~ 150 ℃, preferably 115 ℃ ~ 145 ℃, more preferably 120 ℃ ~ 140 ℃. After curing in the above range, it becomes easy to express stress by the elastic modulus of the anisotropic conductive film.

The composition for anisotropic conductive films of the present invention having such characteristics may include an acrylate-modified urethane resin, a diene rubber resin, a styrene resin, a cellulose resin, and conductive particles.

In another embodiment, the composition for the anisotropic conductive film may include an acrylate-modified urethane resin, a diene rubber resin, a styrene resin, a cellulose resin, a radical polymerizable material, a polymerization initiator, and conductive particles.

In another embodiment, the composition for the anisotropic conductive film may include an acrylate-modified urethane resin, a diene rubber resin, an acrylic copolymer, a styrene resin, a cellulose resin, a radical polymerizable material, a polymerization initiator, and conductive particles. .

Acrylate  Modified urethane resin

Since the acrylate-modified urethane resin has a low glass transition temperature, it is excellent in flowability and high adhesive force is expressed by the urethane group in the molecular chain. In particular, when used in a conductive film, the curing performance can be improved to lower the temperature of the connection process.

The acrylate-modified urethane resin comprises a component of diisocyanate, polyol, diol and acrylate. As the diisocyanate, aromatic, aliphatic, alicyclic diisocyanates, combinations thereof and the like can be used. Polyols have two or more hydroxyl groups in the molecular chain Polyester polyols, polyether polyols, polycarbonate polyols and the like can be used. Diols include 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, triethylene Glycol, tetraethylene glycol and the like can be used. As the acrylate, hydroxy acrylate or amine acrylate may be used.

The acrylate-modified urethane resin including the above four components has a hydroxy group (OH) / diisocyanate group (NCO) molar ratio of 0.5 to 1.0, and the content of polyol is 70% of the three components except for acrylate. A polyaddition polymerization reaction is carried out so that the hydroxy acrylate or amine acrylate is reacted with any one of diisocyanate groups which are terminal functional groups of the urethane synthesized by the polyaddition polymerization reaction in a molar ratio of 0.1 to 2.1. do. In addition, the residual isocyanate groups may be reacted with alcohols to prepare a final acrylate-modified urethane resin. In this case, the polyaddition polymerization step may use a known polyaddition polymerization method. In this step, the reaction temperature is 90 ℃, the reaction pressure is 1 atm, time is 5 hours and the catalyst can be prepared using a tin-based catalyst, but is not limited thereto.

The acrylate-modified urethane resin prepared as described above has a weight average molecular weight of 1,000 to 50,000 g / mol, one or more of the terminal functional group may be made of acrylate. In addition, at least one of the two glass transition temperatures (Tg) represented by the acrylate-modified urethane resin may be 0 ° C. or more.

That is, the acrylate-modified urethane resin exhibits a glass transition temperature at 0 ° C. or higher at a single glass transition temperature of 0 ° C. or higher by phase mixing of a polyol as a soft segment and diisocyanate as a hard segment. It exhibits a function as a binder that plays a role of film formation at room temperature, and also through the acrylate group present in the terminal functional group, the curing reaction is progressed along with the acrylates of the hardened part to perform the role of the hardened part, thereby providing excellent adhesion and high connection. Reliability is shown.

The acrylate-modified urethane resin of the present invention may be included in 30 to 70% by weight, preferably 40 to 60% by weight of the composition for the anisotropic conductive film. It is possible to implement desirable film properties and increase reliability within the above range.

Diene rubber resin

The diene rubber resin is acrylonitrile-butadiene copolymer, styrene butadiene copolymer, (meth) acrylate-butadiene copolymer, (meth) acrylate-acrylonitrile-butadiene-styrene copolymer, carboxyl group-modified acrylonitrile Butadiene rubber or the like may be used, but is not necessarily limited thereto. These may be used alone or in combination of two or more. Among these, preferred are carboxyl group-modified acrylonitrile butadiene rubbers that increase the stability of the resin mixture, improve adhesion by increasing polarity, and improve physical properties such as moisture resistance and heat resistance.

In specific embodiments, a carboxyl group-modified acrylonitrile butadiene rubber having a weight average molecular weight of 2,000 to 200,000 g / mol, preferably 3,000 to 200,000 g / mol may be used. At this time, the acrylonitrile content may be 10 to 60% by weight, preferably 20 to 50% by weight, and the carboxyl group content may be 1 to 20% by weight.

The diene rubber resin may be included in 5 to 25% by weight, preferably 10 to 20% by weight of the composition. In the above range, the composition is not phase separated and the connection reliability is good.

Elastic reinforced resin

As the elastic reinforcement resin One or more types of styrene resin and cellulose resin can be used. In one embodiment, a styrene resin may be used, and in another embodiment, a cellulose resin may be applied. In another embodiment, styrene resin and cellulose resin may be applied together.

Preferably, 20 to 50% by weight of the cellulose resin and 50 to 80% by weight of the styrene resin may be mixed and applied. In the above range, there is an advantage in that voids are not formed by maintaining stress generated by shrinkage / expansion when pressed.

As the styrene-based resin, polystyrene (GPPS) and styrene-based resin may be preferably applied.

The styrene resin may have a weight average molecular weight of 90,000 to 150,000 g / mol, preferably 100,000 to 135,000 g / mol. When the weight average molecular weight of the styrene-based resin is within the above range, the contact is excellent when ACF compression is not caused to cause a poor contact.

The cellulose resin is Cellulose-acetate-butylate resins, cellulose-acetate resins, cellulose-acetate-propionate resins, and the like.

The cellulose-based resin may have a weight average molecular weight of 12,000 to 80,000 g / mol. Preferably from 20,000 to 75,000 g / mol. When the weight average molecular weight of the cellulose-based resin is in the above range, the crude liquid stability is excellent, and it is easy to adhere to the contact substrate during compression.

The elastic resin may be included in 5 to 40% by weight, preferably 10 to 35% by weight of the composition. In the above composition, the elastic modulus is increased to maintain the stress generated by shrinkage / expansion during press bonding, thereby preventing void formation.

Radical Polymerizable  matter

The radically polymerizable material is a component of the hardened portion, and a radical curing reaction occurs to serve to ensure adhesion and connection reliability between the connection layers.

The radically polymerizable material in the connecting material of the present invention is a radically polymerizable material having at least one vinyl group in a molecule, and includes a (meth) acrylate oligomer, a (meth) acrylate monomer or a mixture thereof.

As the (meth) acrylate oligomer, conventional (meth) acrylate oligomers can be used, for example, urethane-based (meth) acrylates having an average molecular weight of about 1,000 to 100,000, epoxy-based (meth) acrylates, polyesters (Meth) acrylate, fluorine (meth) acrylate, fluorene (meth) acrylate, silicone (meth) acrylate, phosphoric acid (meth) acrylate, maleimide modified (meth) acrylate, acrylate ( Methacrylate) and the like.

Specifically, the urethane-based (meth) acrylate is the intermediate structure of the molecule is a polyester polyol (polyester polyol), polyether polyol (polyether polyol), polycarbonate polyol (polycarbonate polyol), polycaprolactone polyol (polycarprolactone polyol), ring Ring-opening tetrahydrofurane-propyleneoxide ring opening copolymer, polybutadiene diol, polydimethylsiloxane diol, ethylene glycol, propylene glycol, 1, 4-butanediol (1,4-butanediol), 1,5-pentanediol (1,5-pentanediol), 1,6-hexanediol (1,6-hexanediol), neopentyl glycol, 1,4 1,4-cyclohexane dimethanol, bisphenol A, hydrogenated bisphenol A, 2,4-toluene diisocyanate, 1, 3-gile Diisocyanate (1,3-xylene diisocyanate), 1,4-xylene diisocyanate, 1,5-naphthalene diisocyanate, 1,6-hexane di What is synthesize | combined from isocyanate (1, 6-hexan diisocyanate), isophorone diisocyanate, bisphenol a propylene oxide modified diacrylate, etc. can be used. As said epoxy (meth) acrylate type, the intermediate molecular structure is bisphenol, such as 2-bromohydroquinone, resorcinol, catechol, bisphenol A, bisphenol F, bisphenol AD, bisphenol S, 4,4'- dihydride Consisting of an alkyl group, an aryl group, a methylol group, an allyl group, a cyclic aliphatic group, a halogen (such as tetrabromobisphenol A), a nitro group, or the like having a skeleton such as oxybiphenyl or bis (4-hydroxyphenyl) ether ( The thing chosen from the group of the meth) acrylate oligomers can be used. In addition, for example, 1-methyl-2,4-bismaleimidebenzene, N, N'-m-phenylenebis containing at least two maleimide groups in a molecule as the (meth) acrylate oligomer of the present invention Maleimide, N, N'-p-phenylenebismaleimide, N, N'-m-toylene bismaleimide, N, N'-4,4-biphenylene bismaleimide, N, N'- 4,4- (3,3'-dimethylbiphenylene) bismaleimide, N, N'-4,4- (3,3'- dimethyl diphenyl methane) bismaleimide, N, N'-4, 4- (3,3'-diethyl diphenyl methane) bismaleimide, N, N'-4,4-diphenylmethane bismaleimide, N, N'-4,4-diphenyl propane bismaleimide, N, N'-4,4- diphenyl ether bismaleimide, N, N'-3,3'- diphenyl thrubis bismaleimide, 2,2-bis (4- (4-maleimide phenoxy) phenyl ) Propane, 2,2-bis (3-s-butyl-4-8 (4-maleimidephenoxy) phenyl) propane, 1,1-bis (4- (4-maleimidephenoxy) ) Phenyl) decane, 4,4'- cyclohexyridenebis (1- (4 maleimide phenoxy) 2-cyclohexyl benzene, 2,2-bis (4- (4 maleimide phenoxy) phenyl)) Hexafluoro propane and the like can be used.

Moreover, as said (meth) acrylate, a normal (meth) acrylate monomer can be used as a monomer, For example, 1, 6- hexanediol mono (meth) acrylate and 2-hydroxy ethyl (meth) acryl Latex, 2-hydroxy propyl (meth) acrylate, 2-hydroxy butyl (meth) acrylate, 2-hydroxy-3-phenyl oxypropyl (meth) acrylate, 1,4-butanediol (meth) acrylate , 2-hydroxyalkyl (meth) acryloyl phosphate, 4-hydroxy cyclohexyl (meth) acrylate, neopentylglycol mono (meth) acrylate, trimethylol-epan di (meth) acrylate, trimethylolpropane Di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, pentaerythritol hexa (meth) acrylate, dipentaerythritol hexa (meth) acrylate , Glycerin di (meth) acrylate, t-hydroperfuryl (meth) acrylate, iso-decyl (meth) acrylate, 2- (2-ethoxyethoxy) ethyl (meth) acrylate, stearyl (meth ) Acrylate, lauryl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, tridecyl (meth) acrylate, ethoxy addition type nonylphenol (meth) acrylate, Ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, t-ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1 , 3-butylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, ethoxy addition bisphenol-A di (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, phenoxy- t-glycol (meth (3) acrylate, 2-methacryloyloxyethyl phosphate, dimethylol tricyclo decaine di (meth) acrylate, trimethylolpropanebenzoate acrylate, fluorene (meth) acrylate, acid phosphoxy ethyl ( Meta) acrylate and the like can be used.

The radically polymerizable material may be included in 10 to 30% by weight of the connection material composition of the present invention. In the case of the above content, it is excellent in reliable characteristics and overall flowability after the compression of the process, and the connection resistance does not increase.

Polymerization initiator

The polymerization initiator used in the present invention serves as a curing agent for generating free radicals by heating or light, and an organic peroxide can be preferably applied.

The organic peroxide is not particularly limited, and various kinds such as ketone peroxide, peroxy ketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxy ester, peroxy carbonate can be used, and connection temperature and time, You may select from a viewpoint of the storage stability of a product, and use a some peroxide together.

In an embodiment, t-butyl peroxylaurate, 1,1,3,3-t-methylbutylperoxy-2-ethyl hexanonate, 2,5-dimethyl-2,5-di (2-ethylhexanoyl Peroxy) hexane, 1-cyclohexyl-1-methylethyl peroxy-2-ethyl hexanonate, 2,5-dimethyl-2,5-di (m-toluoyl peroxy) hexane, t-butyl peroxy Isopropyl monocarbonate, t-butyl peroxy-2-ethylhexyl monocarbonate, t-hexyl peroxy benzoate, t-butyl peroxy acetate, dicumyl peroxide, 2,5, -dimethyl-2,5-di (t-butyl peroxy) hexane, t-butyl cumyl peroxide, t-hexyl peroxy neodecanoate, t-hexyl peroxy-2-ethyl hexanonate, t-butyl peroxy-2-2-ethyl Hexanonate, t-butyl peroxy isobutylate, 1,1-bis (t-butyl peroxy) cyclohexane, t-hexyl peroxy isopropyl monocarbonate, t-butyl peroxy-3,5,5- Trimethyl hexanonate, t-butyl peroxy pivalate, cumyl Oxy neodecanoate, di-isopropyl benzene hydroperoxide, cumene hydroperoxide, isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethyl hexanoyl peroxide, octanoyl peroxide , Lauroyl peroxide, stearoyl peroxide, succinic peroxide, benzoyl peroxide, 3,5,5-trimethyl hexanoyl peroxide, benzoyl peroxy toluene, 1,1,3,3-tetramethyl butyl peroxide Oxy neodecanoate, 1-cyclohexyl-1-methyl ethyl peroxy nodecanoate, di-n-propyl peroxy dicarbonate, di-isopropyl peroxy carbonate, bis (4-t-butyl cyclohexyl ) Peroxy dicarbonate, di-2-ethoxy methoxy peroxy dicarbonate, di (2-ethylhexyl peroxy) dicarbonate, dimethoxy butyl peroxy dicarbonate, di (3-methyl-3-methoxy butyl Peroxy) dicarbonate, 1,1- Bis (t-hexyl peroxy) -3,3,5-trimethyl cyclohexane, 1,1-bis (t-hexyl peroxy) cyclohexane, 1,1-bis (t-butyl peroxy) -3,3 , 5-trimethyl cyclohexane, 1,1- (t-butyl peroxy) cyclododecane, 2,2-bis (t-butyl peroxy) decane, t-butyl trimethyl silyl peroxide, bis (t-butyl) Dimethyl silyl peroxide, t-butyl triallyl silyl peroxide, bis (t-butyl) diallyl silyl peroxide, tris (t-butyl) aryl silyl peroxide, and the like.

In particular, the organic peroxide is preferably used having a half-life temperature of 5 hours to 15 hours at 40 ℃ to 100 ℃. There is no problem in room temperature storage in the above range, it is suitable for fast curing type.

The polymerization initiator may be included in 1 to 5% by weight, preferably 1.5 to 3% by weight of the composition. Excellent compression properties and reworkability in the above range and no bubbles occur.

Conductive particles

The anisotropic conductive film composition of this invention contains electroconductive particle in order to improve the electroconductive performance at the time of a circuit connection.

Such conductive particles may include metal particles including at least one of Au, Ag, Ni, Cu, Pd, Al, Cr, Sn, Ti, and Pb; Carbon particles; Particles coated with the metal particles of particles comprising a resin containing at least one of benzoguanamine, polyethylene, polyester, polystyrene, and polyvinyl alcohol or modified resins thereof; Insulated particles coated with the coated particles with insulating particles; It is preferable that it is one or more selected from.

The size of the said electroconductive particle can be selected and used according to a use in 0.1-30 micrometers range by the pitch of the circuit applied. Preferably it is 0.5-15 micrometers.

In the present invention, the conductive particles are used in the range of 1 to 10% by weight based on the total composition (solid content). Insulation defects and conductivity are not generated in the above range. Preferably it can be used in 2 to 8% by weight, more preferably 3 to 6% by weight.

Acrylic Copolymer

The acrylic copolymer may be optionally included.

Specific examples include acrylate, acrylic acid, metaacrylic acid, methyl methacrylate, vinyl acetate, An acrylic copolymer made by polymerizing an acrylic monomer such as an acrylic monomer modified therefrom can be used, but is not necessarily limited thereto. The acrylic copolymer preferably has a glass transition temperature (Tg) of 50 to 120 ° C. When the glass transition temperature of the acrylic copolymer is in the above range, the connection reliability is excellent and the film is formed well.

In addition, the acrylic copolymer has an acid value of 1 to 100 mgKOH / g by essentially containing a hydroxyl group or a carboxyl group, and may optionally further contain an epoxy group or an alkyl group. Sufficient adhesive force can be expressed in the said range, and connection reliability is excellent.

In particular, the acrylic copolymer has a glass transition temperature of 90 ° C. and an acid value of 3.4 mgKOH / g in order to implement a strong film property, and preferably serves as a binder. Since the urethane binder has a relatively low glass transition temperature, the acrylic copolymer as a binder to be blended together is advantageous in connection reliability as the glass transition temperature is higher. However, when the glass transition temperature of the acrylic copolymer is too high, the breakage characteristic appears due to the properties of the acrylic, the film is not made properly.

The acrylic copolymer is 0 to 15% by weight, preferably 5 to 10% by weight of the total composition.

The composition for anisotropic conductive films of this invention can further mix | blend a coloring pigment, dye, a polymerization inhibitor, a silane coupling agent, etc. in consideration of the property at the time of productization and workability, in order to acquire the target hardened | cured material characteristic. These amounts of addition are well known to those skilled in the art.

The anisotropic conductive film of this invention can be manufactured easily using the composition for anisotropic conductive films of this invention, without a special apparatus or installation. For example, after dissolving the composition of the present invention in an organic solvent such as toluene and liquefying, the conductive particles are stirred for a predetermined time within a speed range in which the conductive particles are not crushed, and then applied to a release film at a thickness of 10 to 50 μm, and then The anisotropic conductive film can be obtained by drying for evaporating time and evaporating an organic solvent.

The invention can be better understood by the following examples, which are intended to illustrate the invention and are not intended to limit the scope of protection defined by the appended claims.

Example

The specification of each component used for the following Example and the comparative example is as follows:

* Acrylate modified urethane resin 1: 50% by volume of methyl ethyl ketone as a solvent, polyol content of 60%, hydroxy / isocyanate molar ratio = 0.5 temperature 90 ℃, pressure 1 atmosphere, reaction time 5 hours, dibutyl tin Polyurethane acrylate synthesized by polyaddition polymerization using ilaurate as a catalyst (weight average molecular weight 25,000 g / mol)

* Acrylate modified urethane resin 2: 50% by volume of methyl ethyl ketone as solvent, polyol content of 60%, hydroxy / isocyanate molar ratio = 1, temperature 90 DEG C, pressure 1 atm, reaction time 5 hours, dibutyl tin Polyurethane acrylate synthesized by polyaddition polymerization using ilaurate as a catalyst (weight average molecular weight 28,000 g / mol)

Rubber component: Acrylonitrile butadiene copolymer dissolved in toluene / methyl ethyl ketone at 25% by volume (1072CGX, Zeon Chemical)

* Acrylic copolymer: Acrylic resin having a weight average molecular weight of 100,000 g / mol dissolved in toluene / methyl ethyl ketone at 40% by volume (AOF7003, Aekyung Chemical)

* Styrene-based resin: Acrylonitrile-alpha-methylstyrene resin (AP-TJ, Cheil Industries) with a weight average molecular weight of 133,000 g / mol dissolved in toluene / methyl ethyl ketone at 40% by volume.

* Cellulose resin: Cellulose-acetate-butylate resin having a weight average molecular weight of 57,000 g / mol dissolved in toluene / methyl ethyl ketone at 25% by volume (CAB-500, Eastman)

* Radical polymerizable material: epoxy acrylate polymer (SP1509, Showa polymer)

Organic Peroxide: Benzoyl Peroxide (Hansol)

* Conductive particle: Conductive particle (Ni particle) of 5㎛ size

Example  1 to 6

Each compounding material was added to the content of Table 1 and stirred for 60 minutes at room temperature (25 ℃) within the speed range in which the conductive particles are not crushed. The combination solution was formed into a 35 μm thick film on a silicone release surface treated polyethylene base film using a casting knife, and dried at 60 ° C. for 5 minutes.

Samples for measuring the elastic modulus and Tg were obtained by placing a 35 μm thick anisotropic conductive film on a heat press, placing a 0.2 mm thick silicone rubber thereon, heating / pressing 190 ° C.-30 MPa-15 min to cure the connecting material, and then releasing the release film. Removed and used.

Comparative Example  1-2

Each blending material was carried out in the same manner as in Example except that the contents of Table 2 were added.

Property measurement method

(1) Elastic modulus: The elastic modulus of the cured sample was measured by TA's Dynamic Mechanical Analyzer (DMA). The measurement sample was cured by using a hot press, it was confirmed that the cured sufficiently by DSC, the elastic modulus was observed while increasing the temperature from -40 ℃ to 200 ℃ at a rate of 10 ℃ / min.

(2) Glass transition temperature: TA TMA (Thermal Mechanical Analyzer) was used to measure the Tg of the cured sample. The measurement sample was cured by using a hot press, it was confirmed that the cured sufficiently by DSC, Tg was measured while increasing the temperature from -40 ℃ to 200 ℃ at a rate of 10 ℃ / min.

(3) Adhesion and poor adhesion: Each film is printed on PCB (Pitch 200㎛, Terminal width 100㎛, Distance between terminals 100㎛, Terminal height 35㎛) and COF film (Pitch 200㎛, Terminal width 100㎛, between terminals Distance 100 µm and terminal height 8 µm) were used under the following conditions.

1) pressurized condition; 70 ° C, 1 second, 1.0 MPa

2) main compression conditions; Five specimens of 150 ° C., 4 seconds, 4.0 MPa (condition 1), 200 ° C., 4 seconds, and 4.0 MPa (condition 2) were prepared. Adhesion was measured with the specimens prepared under condition 1 and shown in the tables, respectively. In addition, the specimen prepared under the condition 2, the adhesion was observed under a microscope.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Acrylate modified urethane resin 1 40 40 30 30 40 30 Acrylate modified urethane resin 2 - - - - - - Rubber components 20 10 10 10 10 10 Acrylic Copolymer 10 10 5 - 5 - Styrenic resin 10 15 20 25 - 40 Cellulose resin 5 5 10 10 15 - Radically polymerizable material 10 15 20 20 20 15 Organic peroxide 2 2 2 2 2 2 Conductive particles 3 3 3 3 3 3 Sum 100 100 100 100 100 100 Modulus of elasticity (MPa) 5000 7000 8000 8500 10000 7500 Tg 115 130 140 140 150 135 Adhesive force (gf / cm) 1100 920 750 720 680 700 Poor adhesion 0/5 0/5 0/5 0/5 0/5 0/5

Comparative Example 1 Comparative Example 2 Acrylate modified urethane resin 1 40 40 Acrylate modified urethane resin 2 30 Rubber components 10 10 Acrylic Copolymer - 30 Styrenic resin - Cellulose resin - Radically polymerizable material 15 15 Organic peroxide 2 2 Conductive particles 3 3 Sum 100 100 Modulus of elasticity (MPa) 300 4500 Tg 65 98 Adhesive force (gf / cm) 1300 980 Poor adhesion 4/5 2/5

As shown in Table 1 and 2 and Figure 2 and in the case of Examples 1 to 6 according to the present invention, the adhesive state is good, and satisfies the adhesive force of 600gf / cm or more. In Comparative Example 1, the elastic modulus and the Tg value are not satisfactory, so that the number of poor adhesive strength due to the stress decreases. In the case of Comparative Example 2, the elastic modulus is good, but the Tg value is low so that the shrinkage of the PCB after crimping cannot be prevented. Lifting between adhesives occurs, resulting in poor adhesion.

Claims (13)

The composition for anisotropic conductive films whose elasticity modulus is 4000 MPa-10000 MPa in 50 degreeC after hardening, and glass transition temperature (Tg) is 110 degreeC-150 degreeC after hardening.

The composition for anisotropic conductive film of claim 1, wherein the composition for anisotropic conductive film comprises an acrylate-modified urethane resin, a diene rubber resin, an elastic reinforcing resin, a radical polymerizable material, a polymerization initiator, and conductive particles. .
The composition for anisotropic conductive film of claim 2, wherein the elastic reinforcing resin is selected from at least one of a cellulose resin and a styrene resin.

The composition of claim 2, wherein the elastic reinforcing resin is made of 20 to 50% by weight of cellulose resin and 50 to 80% by weight of styrene resin.
According to claim 2, wherein the composition for the anisotropic conductive film is 30 to 70% by weight of the acrylate-modified urethane resin, 5 to 25% by weight of the diene rubber resin, 5 to 40% by weight of the elastic reinforcing resin, 10 to 30 radically polymerizable material A composition for an anisotropic conductive film comprising a weight percent, 1 to 5 weight percent of a polymerization initiator, and 1 to 10 weight percent of conductive particles.
According to claim 5, wherein the composition is an anisotropic conductive film composition, characterized in that it further comprises more than 0% to 15% by weight of the acrylic copolymer.
The composition of claim 2, wherein the acrylate-modified urethane resin has a hydroxy group / isocyanate group (NCO) molar ratio of 0.5 to 1.0 and a polyol content of up to 70%.
The method of claim 2, wherein the diene rubber resin is acrylonitrile-butadiene copolymer, styrene butadiene copolymer, (meth) acrylate-butadiene copolymer, (meth) acrylate-acrylonitrile-butadiene-styrene copolymer At least one selected from the group consisting of carboxyl group-modified acrylonitrile-butadiene rubber, composition for anisotropic conductive films.
The composition of claim 2, wherein the cellulose resin has a weight average molecular weight of 12,000 to 80,000 g / mol.

The method of claim 2, wherein the radically polymerizable material is urethane-based (meth) acrylate, epoxy-based (meth) acrylate, polyester-based (meth) acrylate, fluorine-based (meth) acrylate, fluorene-based (meth) acryl Anisotropy which is at least one selected from the group consisting of latex, silicone-based (meth) acrylate, phosphoric acid-based (meth) acrylate, maleimide modified (meth) acrylate, acrylate (methacrylate) and (meth) acrylate monomers Composition for conductive films.
The method of claim 2, wherein the polymerization initiator is at least one member selected from the group consisting of ketone peroxide, peroxy ketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxy ester and peroxycarbonate. Composition for anisotropic conductive film.
The method of claim 2, wherein the conductive particles include metal particles including at least one of Au, Ag, Ni, Cu, Pd, Al, Cr, Sn, Ti, and Pb;
Carbon particles;
Particles coated with the metals of particles comprising resins containing at least one of benzoguanamine, polyolefins, polyesters, polystyrenes and polyvinyl alcohols or modified resins thereof; And
Particles coated with the coated particles;
Composition for anisotropic conductive film, characterized in that at least one selected from.
Anisotropic conductive film formed by the composition of any one of claims 1 to 12.

Images