KR20180017015A - Adhesive composition and connector - Google Patents

Abstract

The present invention provides an adhesive composition comprising (a) a thermoplastic resin, (b) a radically polymerizable compound, and (c) a radical polymerization initiator, wherein the radical polymerizing compound (b) is a radically polymerizable compound having an isocyanate group And a radically polymerizable compound having a structure in which an isocyanate group is formed by heating.

Description

Adhesive composition and connector

The present invention relates to an adhesive composition and a connecting body.

BACKGROUND ART In a semiconductor device or a liquid crystal display device, various adhesive compositions have conventionally been used as circuit connecting materials for the purpose of bonding various members in the device. This adhesive composition is required to have various properties such as adhesiveness, heat resistance, and reliability in a high temperature and high humidity state.

The adherend to be adhered has various surfaces formed of various materials such as organic materials such as printed wiring boards and polyimide films, metals such as copper and aluminum, and metal compounds such as ITO, SiN and SiO ₂ . Therefore, the adhesive composition is designed in accordance with each adherend.

As an adhesive composition for a semiconductor element or a liquid crystal display element, there is known a thermosetting resin composition comprising a thermosetting resin such as an epoxy resin exhibiting high adhesiveness and high reliability (see, for example, Patent Document 1). Such an adhesive composition generally contains an epoxy resin, a curing agent such as a phenol resin reacting with the epoxy resin, and a thermal latent catalyst for promoting the reaction between the epoxy resin and the curing agent. Among them, the thermal latent catalyst is an important factor for determining the curing temperature and the curing rate. Therefore, various compounds have been used as thermal latent catalysts from the viewpoints of storage stability at room temperature and curing rate upon heating. The adhesive composition is generally cured by heating at a temperature of 170 to 250 DEG C for 1 to 3 hours to exhibit desired adhesiveness.

Further, a radical-curing adhesive containing a (meth) acrylate derivative and a peroxide has attracted attention (see, for example, Patent Document 2). Radical curing type adhesives are advantageous from the viewpoint of short-time curing because the reactive radicals are highly reactive.

Japanese Patent Laid-Open No. 1-113480 WO 98/44067

In recent years, along with the high integration of semiconductor devices and the high-definition of liquid crystal devices, pitches between devices and interconnections have narrowed, and heating during curing for circuit connection has a high possibility of adversely affecting peripheral members.

In addition, in order to achieve low cost, there is a need to improve the throughput, to develop an adhesive composition that is cured at a lower temperature and in a shorter time, in other words, an adhesive composition of " low temperature curing ".

In order to achieve the low-temperature curing of the adhesive composition, for example, in the thermosetting resin composition, a thermal latent catalyst having a low activation energy may be used. In this case, it is very difficult to maintain the storage stability near room temperature it's difficult.

On the other hand, the radical-curing adhesive can attain low-temperature fast curing while having storage stability at a level at which no problem occurs in practical use. However, even in the case of using a radical-curing adhesive, in the case of curing under the condition of a lower temperature (for example, 140 ° C or less) as compared with the conventional one, although the radical polymerizing compound in the adhesive mostly reacts, The adhesive strength of the adhesive may not be obtained. This is presumably because the interaction between the adherend and the adhesive under a low-temperature condition is not sufficiently manifested.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and it is an object of the present invention to provide a radical curing type adhesive which can sufficiently exhibit the adhesive strength between an adherend and an adhesive, even under a condition at a lower temperature (for example, And to provide an adhesive composition which is capable of exhibiting the above properties.

The present invention provides an adhesive composition comprising (a) a thermoplastic resin, (b) a radically polymerizable compound, and (c) a radical polymerization initiator, wherein the radical polymerizing compound (b) is a radically polymerizable compound having an isocyanate group, And a radically polymerizable compound having a structure in which an isocyanate group is formed by a radical polymerization initiator. According to such an adhesive composition, the adhesive strength between an adherend and an adhesive can be sufficiently exhibited even at a lower temperature (for example, 140 DEG C or less) as compared with conventional adhesives.

The content of the radically polymerizable compound having an isocyanate group or the structure in which an isocyanate group is formed by heating is preferably 2 to 2 parts by mass based on 100 parts by mass of the total amount of the thermoplastic resin (a) and the radically polymerizable compound (b) To 12 parts by mass. By setting the content in this range, the above-mentioned effect is further enhanced.

The adhesive composition of the present invention may further contain (d) conductive particles. By further containing conductive particles, it is possible to impart conductivity or anisotropic conductivity to the adhesive composition, so that the adhesive composition can be more suitably used as a circuit connecting material. Further, the connection resistance between the circuit electrodes electrically connected through the adhesive composition can be more easily reduced.

The present invention is also characterized in that a first circuit member having a first circuit electrode formed on the main surface of the first circuit substrate and a second circuit electrode formed on the main surface of the second circuit substrate, And a connecting member which is provided between the first circuit member and the second circuit member and electrically connects the first circuit member and the second circuit member to each other, And a cured product of the adhesive composition of the present invention. It is preferable that one of the first circuit board and the second circuit board is a flexible board.

Since the connection member for electrically connecting the first circuit member and the second circuit member to each other is constituted by the cured product of the adhesive composition of the present invention, The adhesive strength of water is sufficiently expressed.

According to the present invention, it is possible to provide an adhesive composition which can sufficiently exhibit the adhesive strength between an adherend and an adhesive even under the condition of a lower temperature (for example, 140 DEG C or less) as compared with conventional adhesives, have. Further, according to such an adhesive composition, the deterioration of the adhesive strength and the connection reliability is sufficiently suppressed even when the adhesive composition is subjected to high temperature and high humidity treatment after bonding to the adherend, and further, the time for use is excellent.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing an embodiment of a film-like adhesive containing an adhesive composition according to the present embodiment. Fig.
Fig. 2 is a schematic cross-sectional view showing an embodiment of a connection member having a connection member including a cured product, according to an embodiment of the present invention. Fig.
Fig. 3 is a process diagram showing an embodiment for manufacturing a connector by an adhesive composition according to the present embodiment, with a schematic sectional view. Fig.

Best Mode for Carrying Out the Invention Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. In the drawings, the same or equivalent portions are denoted by the same reference numerals and redundant explanations are appropriately omitted. Further, in the present specification, (meth) acrylic acid means acrylic acid or the corresponding methacrylic acid. (Meth) acrylate, and the like.

The adhesive composition according to the present embodiment contains (a) a thermoplastic resin, (b) a radically polymerizable compound, and (c) a radical polymerization initiator.

Examples of the thermoplastic resin (a) include polyimide resin, polyamide resin, phenoxy resin, poly (meth) acrylic resin, polyester resin, polyurethane resin, polyester urethane resin, and polyvinyl butyral resin And one kind or two or more kinds of resins selected from the above. Among them, (a) a thermoplastic resin preferably includes a polyimide resin, a polyamide resin, a phenoxy resin, a poly (meth) acrylic resin, a polyurethane resin, a polyester urethane resin or a polyvinyl butyral resin.

The lower limit value of the weight average molecular weight of the thermoplastic resin may be 5000 or more, 10000 or more, and 25000 or more. If the weight average molecular weight of the thermoplastic resin is 5000 or more, the adhesive strength of the adhesive composition tends to be improved. On the other hand, the upper limit of the weight average molecular weight of the thermoplastic resin may be 400000 or less, 200000 or less, or 150000 or less. If the thermoplastic resin has a weight average molecular weight of 400000 or less, good compatibility of other components tends to be obtained, and the fluidity of the adhesive tends to be easily obtained. From the above viewpoint, the weight average molecular weight of the thermoplastic resin is preferably 5000 to 400000, more preferably 5000 to 200000, further preferably 10000 to 150000, and particularly preferably 25000 to 150000.

As the thermoplastic resin, a rubber component may be used for the purpose of stress relaxation and adhesion improvement.

The content of the thermoplastic resin is preferably 20 to 80 parts by mass, more preferably 30 to 70 parts by mass, and more preferably 35 to 65 parts by mass, relative to 100 parts by mass of the total amount of the component (a) and the component (b) desirable. If the content of the thermoplastic resin is 20 parts by mass or more, the adhesive strength tends to be improved or the film-forming property of the adhesive composition tends to be improved. When the content is 80 parts by mass or less, the fluidity of the adhesive tends to be easily obtained.

The adhesive composition according to the present embodiment includes (b) a radically polymerizable compound having an isocyanate group or a radically polymerizable compound having a structure in which an isocyanate group is formed by heating as the radically polymerizable compound.

The radically polymerizable compound preferably contains at least one compound having a structure in which an isocyanate group is produced by an isocyanate group or heating and a compound having a radically polymerizable unsaturated group. The radical polymerizable unsaturated group is preferably a (meth) acryloyl group, more preferably a (meth) acryloyloxy group.

Examples of a method for producing a compound having an isocyanate group and a (meth) acryloyloxy group include a method of reacting a salt of an ester of (meth) acrylic acid and an amino alcohol with phosgene as disclosed in Japanese Patent Application Laid-Open No. 2006-232797 , A method of reacting isopropenyl oxazoline with phosgene, and a method of dehydrochlorinating a 3-chloropropionic acid ester derivative having an isocyanate group.

The molecular weight of the compound having an isocyanate group and a (meth) acryloyloxy group is preferably 150 or more and less than 1,000. If the molecular weight is 150 or more, the compound tends to be less volatile in the process of producing the adhesive composition. If the molecular weight is less than 1000, sufficient fluidity tends to be obtained at the time of heating.

In the compound having an isocyanate group and a (meth) acryloyloxy group, the number of the isocyanate group and the number of the (meth) acryloyloxy group in the molecule is not particularly limited, but it is practically practically each independently about 1 to 5.

Examples of the compound having an isocyanate group and a (meth) acryloyloxy group include 2- (meth) acryloyloxyethyl isocyanate, 2- (meth) acryloyloxymethyl isocyanate, 2- Propyl isocyanate, and 1,1- (bisacryloyloxymethyl) ethyl isocyanate.

The adhesive composition according to the present embodiment may contain (b) a radically polymerizable compound having a structure in which an isocyanate group is formed by heating, as a radical polymerizing compound. By using such a compound, the usable time of the adhesive can be further improved.

The structure in which an isocyanate group is generated by heating can be synthesized by chemically blocking an isocyanate group with a block agent or the like. Examples of the blocking agent include dimethyl pyrazole, dimethyl malonate, diethyl malonate, methyl ethyl ketone oxime and caprolactam. These block agents can be used singly or in combination of two or more kinds in accordance with the practical temperature in that the temperature at which the block agent dissociates can be controlled according to the type of the block agent.

As the compound synthesized by the above-mentioned method and having a structure in which an isocyanate group is produced by heating and a (meth) acryloyloxy group, for example, a compound having an isocyanate group and a (meth) acryloyloxy group, Blocked compounds. Specific examples thereof include 2- (0- [1'-methylpropylideneamino] carboxyamino) ethyl (meth) acrylate.

The total content of the radically polymerizable compound having an isocyanate group or the radical polymerizable compound having a structure in which an isocyanate group is formed by heating is preferably from 2 to 12 mass parts based on 100 parts by mass of the total amount of the component (a) and the component (b) More preferably 3.5 to 10 parts by mass, and still more preferably 4 to 9 parts by mass. When the content is 2 parts by mass or more, the bonding strength with an adherend tends to be higher. When the content is 12 parts by mass or less, the time for which the adhesive is used tends to be further improved. Further, generation of bubbles after curing can be suppressed, and better connection reliability can be obtained.

The adhesive composition according to the present embodiment is prepared by adding a radically polymerizable compound having an isocyanate group or a radically polymerizable compound having a structure in which an isocyanate group is formed by heating to a radical polymerizable compound having (b) a radically polymerizable functional group And the like. The other compound may be, for example, any of monomers and oligomers of the compounds described later, or both of them may be used in combination.

As such a compound, one or more polyfunctional (meth) acrylate compounds having two or more (meth) acryloyloxy groups are preferable. Examples of such (meth) acrylate compounds include epoxy (meth) acrylate, urethane (meth) acrylate, polyether (meth) acrylate, polyester (meth) acrylate, trimethylolpropane tri (Meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, neopentyl glycol di (meth) acrylate such as polyethylene glycol di (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, isocyanuric acid-modified bifunctional (meth) acrylate and isocyanuric acid-modified trifunctional (meth) acrylate. Examples of the epoxy (meth) acrylate include epoxy (meth) acrylates obtained by adding (meth) acrylic acid to two glycidyl groups of bisphenol fluorene diglycidyl ether and bisphenol fluorene diglycidyl ether (Meth) acryloyloxy group is introduced into a compound obtained by adding ethylene glycol and / or propylene glycol to two glycidyl groups. These compounds may be used singly or in combination of two or more.

The adhesive composition may also contain a monofunctional (meth) acrylate compound as the radically polymerizable compound (b) for the purpose of controlling the flowability and the like. Examples of the monofunctional (meth) acrylate compound include pentaerythritol (meth) acrylate, 2-cyanoethyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentenyl (meth) (Meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, 2- (2-ethoxyethoxy) ethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, n-hexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, isobornyl Acrylate, 2-methoxyethyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2- Methacryloyloxyethyl phosphate, N, N-dimethylaminoethyl (meth) acrylate, (Meth) acrylate obtained by reacting one glycidyl group of an epoxy resin having a plurality of glycidyl groups with (meth) acrylic acid, and a (meth) acrylate containing a glycidyl group obtained by reacting Meth) acryloylmorpholine. These compounds may be used singly or in combination of two or more.

The adhesive composition may also contain a radically polymerizable compound (b) having a radically polymerizable functional group such as an allyl group, a maleimide group or a vinyl group for the purpose of improving the crosslinking rate or the like.

The adhesive composition preferably contains a radically polymerizable compound having a phosphoric acid group as the radically polymerizable compound (b) for the purpose of improving the adhesive strength. Examples of the radically polymerizable compound having a phosphoric acid group include compounds represented by the following formula (1), (2) or (3).

In the formula (1), R ⁵ represents a hydrogen atom or a methyl group, R ⁶ represents a (meth) acryloyloxy group, and w and x each independently represent an integer of 1 to 8. Further, a plurality of R ⁵ , R ⁶ , w and x in the same molecule may be the same or different.

In the formula (2), R ⁷ represents a (meth) acryloyloxy group, and y and z each independently represent an integer of 1 to 8. A plurality of R ⁷ , y and z in the same molecule may be the same or different.

In the formula (3), R ⁸ represents a hydrogen atom or a methyl group, R ⁹ represents a (meth) acryloyloxy group, and b and c each independently represent an integer of 1 to 8. A plurality of R ⁸ and b in the same molecule may be the same or different.

Examples of the radically polymerizable compound having a phosphoric acid group include acid phosphooxyethyl (meth) acrylate, acid phosphoxypropyl (meth) acrylate, acid phosphoxypolyoxyethylene glycol mono (meth) acrylate, (Meth) acrylate, phosphoric acid modified epoxy (meth) acrylate, phosphoric acid modified epoxy (meth) acrylate, phosphonium oxypropylene glycol mono (meth) acrylate, 2,2'- Acrylate, and vinyl phosphate. These compounds may be used singly or in combination of two or more.

The content of the radical polymerizing compound having a phosphoric acid group is preferably 0.1 to 15 parts by mass, more preferably 0.5 to 10 parts by mass, and more preferably 1 to 5 parts by mass, relative to 100 parts by mass of the total amount of the component (a) Mass part is more preferable. When the content of the radically polymerizable compound having a phosphoric acid group is 0.1 parts by mass or more, a high adhesive strength tends to be obtained. When the content is 15 parts by mass or less, the physical properties of the adhesive composition after curing are hardly lowered, .

The total content of the radically polymerizable compound (b) contained in the adhesive composition is preferably 20 to 80 parts by mass, more preferably 30 to 70 parts by mass per 100 parts by mass of the total amount of the components (a) and (b) And more preferably 35 to 65 parts by mass. When the total content is 20 parts by mass or more, heat resistance tends to be improved. When the total content is 80 parts by mass or less, the effect of suppressing peeling after leaving in a high temperature and high humidity environment tends to increase.

The radical polymerization initiator (c) may be selected from compounds such as peroxides and azo compounds. From the viewpoints of stability, reactivity and compatibility, peroxides having a half-life temperature for one minute of 90 to 175 DEG C and a molecular weight of 180 to 1000 are preferred. The "one-minute half-life temperature" means a temperature at which the half-life of peroxide is one minute. The term " half-life period " means a period of time until the concentration of the compound decreases to half of the initial value at a predetermined temperature.

Examples of the radical polymerization initiator include 1,1,3,3-tetramethylbutyl peroxyneodecanoate, di (4-t-butylcyclohexyl) peroxydicarbonate, di (2-ethylhexyl) 1,1,3,3-tetramethylbutyl peroxyneodecanoate, dilauryl peroxide, 1-cyclohexyl-1-methylethyl peroxyneodecane, 1,1,3,3-tetramethylbutyl peroxyneodecanoate, T-butyl peroxyneodecanoate, t-butyl peroxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate Butyl peroxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane, t-butylperoxy neoheptanoate, t-amylperoxy-2-ethylhexanoate, di-t-butylperoxyhexahydroterephthalate, t-amylperoxy-3,5,5-trimethylhexano 3-hydroxy-1,1-di T-butylperoxy neodecanoate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, t-amylperoxy neodecanoate, t-amylperoxy-2-ethylhexa (3-methylbenzoyl) peroxide, dibenzoyl peroxide, di (4-methylbenzoyl) peroxide, 2,2'-azobis- Azobis (1-acetoxy-1-phenylethane), 2,2'-azobisisobutyronitrile, 2,2'-azobis (2- Azobis (4-cyanobalenoic acid), 1,1'-azobis (1-cyclohexanecarbonitrile), dimethyl- ), t-hexylperoxyisopropyl monocarbonate, t-butylperoxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, 2,5 -Dimethyl-2,5-di (3-methylbenzoylperoxy) hexane, t-butylperoxy-2-ethylhexylmonocar Hexylperoxybenzoate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxybenzoate, dibutylperoxytrimethyladipate, t- Octoate, t-amyl peroxyisonanoate and t-amyl peroxybenzoate.

The content of the radical polymerization initiator is preferably 1 to 15 parts by mass, more preferably 2.5 to 10 parts by mass, and more preferably 3 to 8 parts by mass, relative to 100 parts by mass of the total amount of the components (a) and (b) desirable.

The adhesive composition according to the present embodiment may contain a silane coupling agent. The silane coupling agent is preferably a compound represented by the following formula (4).

In formula (4), R ¹ , R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkoxycarbonyl group having 1 to 5 carbon atoms, or an aryl group. At least one of R ¹ , R ² and R ³ is an alkoxy group. R ⁴ represents an amino group optionally substituted with a (meth) acryloyl group, a (meth) acryloyloxy group, a vinyl group, an isocyanato group, an imidazole group, a mercapto group or an aminoalkyl group, a methylamino group, a dimethylamino group, , A phenylamino group, a cyclohexylamino group, a morpholino group, a piperazino group, a ureide group, a glycidyl group, or a glycidoxy group. a represents an integer of 0 to 10;

Examples of the silane coupling agent of the formula (4) include vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3- ( (Meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropylmethyldiethoxysilane, 3- Aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, and 3-aminopropyltrimethoxysilane. 3-isocyanatopropyltriethoxysilane. These compounds may be used singly or in combination of two or more.

The content of the silane coupling agent is preferably 0.1 to 10 parts by mass, more preferably 0.25 to 5 parts by mass, per 100 parts by mass of the total amount of the component (a) and the component (b). When the content of the silane coupling agent is 0.1 parts by mass or more, the effect of suppressing the interface separation between the circuit member and the circuit connecting material and the generation of air bubbles tends to become greater. When the content of the silane coupling agent is 10 parts by mass or less, The usable time of the battery pack tends to be longer.

The adhesive composition according to the present embodiment may further contain (d) conductive particles. The adhesive composition containing conductive particles can be particularly preferably used as the anisotropic conductive adhesive.

Examples of the conductive particles include metal particles such as Au, Ag, Pd, Ni, Cu, and solder, and carbon particles. The conductive particles may be composite particles having core particles containing non-conductive materials such as glass, ceramics, and plastics, and conductive layers such as metal, metal particles, and carbon covering the core particles. The metal particles may be copper particles and particles having a silver layer covering the copper particles. The core particle of the composite particle is preferably a plastic particle.

Since the composite particles comprising the plastic particles as core particles have deformability that is deformed by heating and pressing, when the circuit members are bonded to each other, the contact area between the circuit electrodes of the circuit member and the conductive particles can be increased. Therefore, according to the adhesive composition containing these composite particles as the conductive particles, a connecting material having a better connection reliability can be obtained.

The adhesive composition may contain an insulating coating conductive particle having an insulating layer or insulating particles covering the conductive particles and at least a part of the surface of the conductive particles. The insulating layer can be provided by a method such as hybridization. The insulating layer or insulating particles are formed of an insulating material such as a polymer resin. By using such insulating coated conductive particles, it is difficult for short-circuiting between adjacent conductive particles to occur.

The average particle diameter of the conductive particles is preferably 1 to 18 mu m from the viewpoint of obtaining good dispersibility and conductivity.

The content of the conductive particles is preferably 0.1 to 30% by volume, more preferably 0.1 to 10% by volume, and still more preferably 0.5 to 7.5% by volume based on the total volume of the adhesive composition. When the content of the conductive particles is 0.1% by volume or more, the conductivity tends to be improved. When the content of the conductive particles is 30% by volume or less, short circuit between the circuit electrodes tends to be less likely to occur. The content (volume%) of the conductive particles is determined based on the volume of each component constituting the adhesive composition before curing at 23 캜. The volume of each component can be obtained by converting mass to volume using specific gravity. A suitable solvent (water, alcohol, or the like) for sufficiently wetting the component is put into a measuring cylinder without dissolving or swelling the component whose volume is to be measured, It can also be obtained as a volume.

The adhesive composition may contain insulating organic or inorganic fine particles in addition to the conductive particles. Examples of the inorganic fine particles include nitride fine particles and the like as well as metal oxide fine particles such as silica fine particles, alumina fine particles, silica-alumina fine particles, titania fine particles and zirconia fine particles. Examples of the organic fine particles include silicon fine particles, methacrylate-butadiene-styrene fine particles, acrylic-silicon fine particles, polyamide fine particles, and polyimide fine particles. These fine particles may have a uniform structure or may have a core-shell type structure.

The content of the organic fine particles and the inorganic fine particles is preferably 5 to 30 parts by mass, more preferably 7.5 to 20 parts by mass, per 100 parts by mass of the total amount of the components (a) and (b). When the content of the organic fine particles and the inorganic fine particles is 5 parts by mass or more, it is relatively easy to maintain the electrical connection between the electrodes. When the content is 30 parts by mass or less, the fluidity of the adhesive composition tends to be improved.

The adhesive composition may contain various additives.

The adhesive composition according to the present embodiment can be used as a paste-like adhesive when it is liquid at room temperature (25 캜). When the adhesive composition is a solid at room temperature, it may be heated or may be used as a paste by adding a solvent. The solvent used for paste-making is not particularly limited as long as it has substantially no reactivity of the adhesive composition (including additives) and can sufficiently dissolve the adhesive composition.

The adhesive composition according to the present embodiment may be molded into a film and used as an adhesive on a film. The film-like adhesive can be obtained, for example, by applying a solution obtained by adding a solvent or the like to the adhesive composition as required, for example, on a releasable support such as a fluororesin film, a polyethylene terephthalate film or a release paper, Can be obtained by the method. The film-like adhesive is more convenient in terms of handling and the like.

1 is a schematic cross-sectional view showing one embodiment of a film-like adhesive containing the adhesive composition according to the present embodiment. The laminated film 100 shown in Fig. 1 has a support 8 and a film-like adhesive 40 that is peelably laminated on the support 8. The film adhesive 40 is composed of an insulating adhesive layer 5 and conductive particles 7 dispersed in the insulating adhesive layer 5. [ The insulating adhesive layer 5 is composed of components other than the conductive particles in the above-mentioned adhesive composition. According to this film-like adhesive, it is easy to handle, can be easily installed on an adherend, and can be easily connected. The film-like adhesive may have a multilayer structure including two or more layers. When the film-like adhesive contains conductive particles, a film-like adhesive may be suitably used as the anisotropic conductive film.

According to the adhesive composition and the film-like adhesive according to the present embodiment, adherends can be adhered to each other by commonly using heating and pressurization. The heating temperature is preferably 100 to 250 ° C. The pressure is not particularly limited as long as it does not cause damage to the adherend, but it is generally preferably 0.1 to 10 MPa. These heating and pressurization are preferably performed in the range of 0.5 to 120 seconds. According to the adhesive composition and the film-like adhesive according to the present embodiment, it is possible to sufficiently adhere adherends even under short-term heating and pressurization for 5 seconds at, for example, 140 deg. C and 3 MPa or so.

The adhesive composition and the film-like adhesive according to the present embodiment can be used as different kinds of adherend adhesives having different thermal expansion coefficients. Specifically, the adhesive composition and the film-like adhesive according to the present embodiment can be used not only as an anisotropic conductive adhesive but also as a semiconductor device adhesive material such as a circuit connecting material such as silver paste and silver film, an elastomer for CSP, an underfill material for CSP, Can be used.

Hereinafter, an example in which the film-like adhesive according to the present embodiment is used as an anisotropic conductive film, circuit members having circuit electrodes and circuit electrodes formed on the main surface of a circuit board are connected to each other as an adherend, Explain.

Fig. 2 is a schematic cross-sectional view showing an embodiment of a connection body in which the adhesive composition according to the embodiment is provided with a connection member including a cured product. Fig. The connector 1 shown in Fig. 2 is provided with a first circuit member 20 and a second circuit member 30 arranged to face each other. Between the first circuit member 20 and the second circuit member 30, a connecting member 10 for bonding and connecting them is provided.

The first circuit member 20 includes a first circuit substrate 21 and a first circuit electrode 22 formed on the main surface 21a of the first circuit substrate 21. The first circuit member 21 has a first circuit electrode 22, An insulating layer may be formed on the main surface 21a of the first circuit substrate 21. [

The second circuit member 30 has a second circuit board 31 and a second circuit electrode 32 formed on the main surface 31a of the second circuit board 31. [ An insulating layer may also be formed on the main surface 31a of the second circuit board 31. [

The first circuit member 20 and the second circuit member 30 are not particularly limited as long as they have circuit electrodes that require electrical connection. Examples of the first circuit substrate 21 and the second circuit substrate 31 include substrates of inorganic materials such as semiconductor, glass and ceramics, substrates of organic materials such as polyimide and polycarbonate, glass / epoxy And a substrate including an inorganic material and an organic material. The first circuit substrate 21 may be a glass substrate and the second circuit substrate 31 may be a flexible substrate (preferably, a resin film such as a polyimide film).

Specific examples of the circuit member to be connected include a glass or plastic substrate on which an electrode such as an indium tin oxide (ITO) film is formed, a printed wiring board, a ceramic wiring board, a flexible wiring board, and a semiconductor silicon chip used in a liquid crystal display . These are used in combination as needed. As described above, according to the adhesive composition of this embodiment, in addition to members having a surface formed from organic materials such as printed wiring boards and polyimide films, metals such as copper, aluminum, ITO, silicon nitride (SiN _x ), silicon dioxide ₂ ), or the like having a surface formed of an inorganic material such as a polyimide resin or a polyimide resin.

For example, when one circuit member is a solar cell having electrodes such as finger electrodes and bus bar electrodes, and the other circuit member is a tap line, the connecting member obtained by connecting them is a solar cell, a tab line, (A cured product of an adhesive composition) to be adhered to each other.

The connecting member 10 includes the cured product of the adhesive composition according to the present embodiment. The connecting member 10 contains the insulating layer 11 and the conductive particles 7 dispersed in the insulating layer 11. The conductive particles 7 are disposed not only between the first circuit electrode 22 and the second circuit electrode 32 but also between the main surfaces 21a and 31a. Since the first circuit electrode 22 and the second circuit electrode 32 are electrically connected through the conductive particles 7, the connection resistance between the first circuit electrode 22 and the second circuit electrode 32 Is sufficiently reduced. Thus, the current flow between the first circuit electrode 22 and the second circuit electrode 32 can be smoothly performed, and the function of the circuit can be sufficiently exhibited. When the connecting member does not contain conductive particles, the first circuit electrode 22 and the second circuit electrode 32 are brought into contact with each other to be electrically connected.

The bonding strength of the connecting member 10 to the first circuit member 20 and the second circuit member 30 is set to be higher than that of the connecting member 10 in that the connecting member 10 is formed of the cured product of the adhesive composition of the present embodiment It is high enough. Therefore, even after the reliability test (high temperature and high humidity test), the decrease of the bonding strength and the increase of the connection resistance can be sufficiently suppressed.

The connection member 1 includes, for example, a step of arranging a pair of circuit members disposed opposite to each other with a circuit electrode therebetween through a film-like adhesive containing an adhesive composition, a pair of circuit members and a film- (A connecting step) of adhering a pair of circuit members to each other through a cured product of an adhesive composition, while heating the adhesive in a thickness direction of the film-like adhesive and curing the adhesive.

Fig. 3 is a process diagram showing an embodiment in which a connector is manufactured by the adhesive composition according to the present embodiment, with a schematic sectional view. 3 (a), a film-like adhesive 40 is stacked on the main surface of the first circuit member 20 on the first circuit electrode 22 side. When the film-like adhesive 40 is provided on the above-mentioned support, in the direction in which the film-like adhesive 40 is located on the first circuit member 20 side, a laminate of the film- do. The film-like adhesive 40 is easy to handle since it is in the form of a film. This makes it possible to easily interpose the film adhesive 40 between the first circuit member 20 and the second circuit member 30 and to prevent the adhesive between the first circuit member 20 and the second circuit member 30 The connection operation can be easily performed.

The film-like adhesive 40 is the above-described adhesive composition (circuit connecting material) formed in a film form, and has the conductive particles 7 and the insulating adhesive layer 5. The adhesive composition can be used as a circuit connecting material for electrical connection by directly connecting the circuit electrodes to each other even when the conductive particles are not contained. A circuit connecting material not containing conductive particles may be referred to as NCF (Non-Conductive-FILM) or NCP (Non-Conductive-Paste). When the adhesive composition has conductive particles, the circuit connecting material using the conductive particles may be referred to as ACF (Anisotropic Conductive FILM) or ACP (Anisotropic Conductive Paste).

The thickness of the film-like adhesive 40 is preferably 10 to 50 mu m. If the thickness of the adhesive agent 40 on the film is 10 m or more, the gap between the first circuit electrode 22 and the second circuit electrode 32 tends to be easily filled with the adhesive. The adhesive composition between the first circuit electrode 22 and the second circuit electrode 32 can be sufficiently removed and the thickness of the first circuit electrode 22 and the second circuit electrode 32 Can be easily ensured.

The film adhesive 40 is temporarily connected to the first circuit member 20 by applying the pressures A and B in the thickness direction of the film adhesive 40 as shown in Figure 3 (a) 3 (b)). At this time, it may be pressurized while heating. However, the heating temperature is set at a temperature at which the adhesive composition in the film-like adhesive 40 is not cured, that is, a temperature sufficiently lower than a temperature at which the radical polymerization initiator abruptly generates radicals.

Subsequently, as shown in Fig. 3 (c), the second circuit member 30 is placed on the film-like adhesive 40 in the direction in which the second circuit electrode is positioned on the first circuit member 20 side Load. When the film-like adhesive 40 is provided on the support, the second circuit member 30 is placed on the adhesive 40 on the film after the support is peeled off.

Thereafter, the film-like adhesive 40 is heated while applying pressure A and pressure B in the thickness direction thereof. The heating temperature at this time is set to a temperature at which the radical polymerization initiator sufficiently generates radicals. As a result, radicals are generated from the radical polymerization initiator and polymerization of the radical polymerizable compound is initiated. By this connection, the connection body shown in Fig. 2 is obtained. The insulating adhesive 11 is formed by heating the adhesive agent 40 on the film so that the distance between the first circuit electrode 22 and the second circuit electrode 32 is sufficiently small. As a result, the first circuit member 20 and the second circuit member 30 are firmly connected through the connecting member 10 including the insulating layer 11.

The connection is preferably performed under the conditions of a heating temperature of 100 to 250 DEG C, a pressure of 0.1 to 10 MPa, and a pressing time of 0.5 to 120 seconds. These conditions are appropriately selected depending on the application to be used, the adhesive composition, and the circuit member. According to the adhesive composition of this embodiment, it is possible to obtain a connector having sufficient reliability even under a low-temperature condition such as 140 占 폚 or less. After the connection, post curing may be performed as necessary.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the following examples.

<Synthesis of urethane acrylate>

4000 parts by mass of a polycarbonate diol (number-average molecular weight Mn = 2000, manufactured by Aldrich Co.) was added to a 2-liter four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet and a reflux condenser, and 2-hydroxyethyl acrylate , 0.49 parts by mass of hydroquinone monomethyl ether, and 4.9 parts by mass of a tin catalyst were added. 666 parts by mass of isophorone diisocyanate (IPDI) was uniformly added dropwise to the reaction liquid heated at 70 占 폚 over 3 hours and reacted. After completing the dropwise addition, the reaction was continued for 15 hours. When the NCO content was confirmed to be 0.2 mass% in the potentiometric automatic titration apparatus (trade name: AT-510, manufactured by Kyoto Denshi Kogyo K.K.), the reaction was terminated and the urethane acrylate . As a result of analysis by GPC (gel permeation chromatography), the weight average molecular weight of the urethane acrylate was 8500 (in terms of standard polystyrene). The analysis by GPC was carried out under the conditions shown in Table 1 below.

&Lt; Preparation of conductive particles &

A nickel layer having a thickness of 0.2 占 퐉 was formed on the surface of polystyrene particles and a gold layer having a thickness of 0.04 占 퐉 was formed on the outside of these nickel layers. Thus, conductive particles having an average particle diameter of 4 탆 were produced.

&Lt; Preparation of film-like adhesive &

The raw materials shown in Table 2 were mixed at a mass ratio shown in Table 2. The conductive particles were dispersed therein in a proportion of 1.5% by volume to obtain a coating solution for forming a film-like adhesive agent. This coating solution was applied to a polyethylene terephthalate (PET) film having a thickness of 50 탆 by using a coating apparatus. The coated film was hot-air dried at 70 캜 for 10 minutes to form a film-like adhesive having a thickness of 18 탆.

Each numerical value shown in Table 2 represents the mass part of the solid content. Specific materials of the respective materials shown in Table 2 are as follows.

Urethane acrylate: a composition synthesized as described above,

Radical polymerizable compound A: Methacryloyloxyethyl isocyanate (molecular weight 155.15, purity 99%),

Radical polymerizable compound B: 2- (0- [1'-methylpropylideneamino] carboxyamino) ethyl methacrylate (molecular weight 240.00, purity 99%),

Radical Polymerizable Compound C: monofunctional acrylate compound (trade name: ARIX CHA, manufactured by TOAGOSEI CO., LTD .: cyclohexyl acrylate),

Phenoxy resin: 40% by mass of a solution prepared by dissolving 40 g of PKHC (trade name, manufactured by Union Carbide, average molecular weight: 45000) in 60 g of methyl ethyl ketone,

Phosphoric ester: 2-methacryloyloxyethyl acid phosphate (trade name: LIGHT ESTER P-2M, manufactured by Kyoeisha Chemical Co., Ltd.)

Silane coupling agent: 3-methacryloxypropyltrimethoxysilane (trade name: KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.)

Peroxide: Lauroyl peroxide (product name: Peroyl L, manufactured by Nippon Oil Co., Ltd., molecular weight: 398.6)

10% by mass dispersion prepared by dispersing 10 g of silica fine particles (trade name: R104, manufactured by Nippon Aerosil Co., Ltd.) in a mixed solvent of 45 g of toluene and 45 g of ethyl acetate.

<Fabrication of Connecting Body>

(FPC) having 2200 copper circuits each having a line width of 75 mu m, a pitch of 150 mu m and a thickness of 18 mu m using the film-like adhesive as a circuit connecting material, and a flexible circuit board An ITO substrate (thickness: 1.1 mm, surface resistance: 20? /?) Having a thin layer of indium oxide (ITO) was connected. The connection was performed by heating and pressing at 140 DEG C and 3 MPa for 5 seconds using a thermocompression bonding apparatus (heating method: Constant heat type, manufactured by Toray Engineering Co., Ltd.). As a result, a connection body in which an FPC and an ITO substrate were connected to each other by a cured product of a film-like adhesive over a width of 1.5 mm was produced.

&Lt; Measurement of connection resistance and adhesive strength >

The resistance value (connection resistance) between adjacent circuits of the obtained connecting member was measured by a multimeter. The resistance value was expressed as an average of 37 points of resistance between adjacent circuits. Further, the adhesive strength of the connector was measured by a 90 degree peeling method in accordance with JIS-Z0237. Tensilon UTM-4 (trade name, manufactured by Toyo Baldwin Co., Ltd., peeling strength: 50 mm / min, 25 캜) was used as a measuring device for the adhesive strength. The connection resistance and the bonding strength were measured for the connection body immediately after connection and after holding for 250 hours in a constant temperature and humidity bath at 85 DEG C and 85% RH. The evaluation results are shown in Table 3.

&Lt; Evaluation of available time &

The above-mentioned film-like adhesive treated at 40 占 폚 for 3 days was used as a circuit connecting material, and a connection member was prepared by the same method as above, and the connection resistance and the adhesive strength were measured by the above method. The evaluation results are shown in Table 3.

With the film-like adhesive of each of the examples, a good connection resistance (5 Ω or less) and an adhesive strength (6N / cm) were obtained in all the cases immediately after the connection, after the high temperature and high humidity test, Cm or more). Particularly, in Example 5 using a film-like adhesive containing a radical polymerizable compound having a structure in which an isocyanate group was formed by heating, the adhesive strength after treatment at 40 占 폚 for 3 days was more excellent and the usable time was further improved The work was confirmed.

On the other hand, in the case of the film-type adhesive of Comparative Example 1 which does not completely contain a radically polymerizable compound having an isocyanate group or a radically polymerizable compound having a structure in which an isocyanate group is formed by heating as a radically polymerizable compound, It was confirmed that sufficient adhesion strength could not be obtained in all the cases after the high humidity test and after 3 days of treatment at 40 占 폚 as compared with the respective examples.

1:
5: Insulating adhesive layer
7: conductive particles
8: Support
10:
11: Insulating layer
20: first circuit member
21: first circuit board
21a:
22: first circuit electrode
30: second circuit member
31: second circuit board
31a:
32: second circuit electrode
40: adhesive on film
100: laminated film

Claims (5)

(a) a thermoplastic resin,
(b) a radical polymerizing compound, and
(c) a radical polymerization initiator
&Lt; / RTI &gt;
(B) the radically polymerizable compound comprises a radically polymerizable compound having an isocyanate group or a radically polymerizable compound having a structure in which an isocyanate group is formed by heating. The thermosetting resin composition according to claim 1, wherein the radical polymerizing compound having an isocyanate group or the radical polymerizing compound having a structure in which an isocyanate group is formed by heating is contained in the total amount of the thermoplastic resin (a) and the radical polymerizing compound (b) Is 2 to 12 parts by mass relative to 100 parts by mass of the adhesive composition. The adhesive composition according to claim 1 or 2, further comprising (d) conductive particles. A first circuit member having a first circuit electrode formed on a main surface of the first circuit board,
A second circuit member having a second circuit electrode formed on a main surface of the second circuit board, the second circuit electrode being disposed so as to face the first circuit electrode,
A connecting member provided between the first circuit member and the second circuit member for electrically connecting the first circuit member and the second circuit member;
And,
Wherein the connecting member is a cured product of the adhesive composition according to any one of claims 1 to 3. 5. The connector according to claim 4, wherein one of the first circuit board and the second circuit board is a flexible board.

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