KR102329065B1 - Circuit connection material, circuit connection structure, adhesive film, and wound body - Google Patents

Abstract

The present invention is a circuit connection material for electrically connecting two circuit members facing each other, comprising a thermoplastic resin, a radically polymerizable compound, a radical polymerization initiator, and inorganic fine particles, and the content of the radically polymerizable compound is that of the circuit connection material. 40% by mass or more based on the total amount, the content of the compound having a molecular weight of 1000 or less in the radical polymerizable compound is 15% by mass or less based on the total amount of the circuit connection material, and the content of the inorganic fine particles is 5 to 30 based on the total amount of the circuit connection material It is mass % and it is related with the circuit connection material containing at least the compound represented by following formula (1).
<Formula 1>

Description

Circuit connection material, circuit connection structure, adhesive film and rolled body

The present invention relates to a circuit connection material for electrically connecting two circuit members opposing each other, and a circuit connection structure, an adhesive film, and a rolled body using the same.

DESCRIPTION OF RELATED ART In a semiconductor element and a liquid crystal display element, various circuit connection materials are conventionally used for the purpose of joining various members in an element. The properties required for a circuit connection material cover a wide range of properties, such as adhesiveness, heat resistance, and reliability in a high-temperature, high-humidity state.

Further, as the adherend to be adhered with the circuit connection material, for example, a printed wiring board, an organic substrate such as polyimide, polyethylene terephthalate and polycarbonate, a metal substrate such as copper and aluminum, and ITO, IZO, SiN and there may be mentioned an inorganic base material of SiO ₂ or the like, a base material having a great variety of surface conditions, is used. Therefore, the circuit connection material requires molecular design according to each adherend (for example, Patent Documents 1 and 2).

Conventionally, as a circuit connection material for semiconductor elements or liquid crystal display elements, a thermosetting resin composition using an epoxy resin showing high adhesiveness and high reliability has been used (for example, refer to Patent Document 1). As constituent components of such a thermosetting resin composition, an epoxy resin, a curing agent such as a phenol resin having reactivity with the epoxy resin, and a thermal latent catalyst that promotes the reaction between the epoxy resin and the curing agent are generally used.

In the actual process, the above-mentioned circuit connection material had obtained desired adhesion|attachment by hardening at the temperature of 170-250 degreeC for 1 to 3 hours. However, with the recent high integration of semiconductor devices and high precision of liquid crystal devices, the pitch between devices and between wirings is narrowed, and there is a concern that heating during curing may adversely affect peripheral members.

Moreover, in order to reduce cost, it is necessary to improve a throughput, and hardening at a lower temperature and a shorter time, in other words, adhesion in low-temperature rapid hardening is calculated|required. In order to achieve this low-temperature rapid curing, it is necessary to use a thermal latent catalyst with a low activation energy, and it is very difficult to have storage stability in the vicinity of room temperature.

In recent years, a radical curing adhesive obtained by using an acrylate derivative and/or a methacrylate derivative (hereinafter referred to as a (meth)acrylate derivative) and a peroxide serving as a radical polymerization initiator in combination is attracting attention. Since radical curing adhesives have many reactive radicals as reactive active species, curing for a short period of time is possible (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. Hei1-113480 International Publication No. 98/44067 pamphlet

However, since cure shrinkage of (meth)acrylate is large compared with cure shrinkage of epoxy resins in radical curable adhesives, when the bonded structure is left under a high-temperature, high-humidity environment such as 85°C and 85% RH, for example, circuit members A peeling bubble will generate|occur|produce in the interface of a and circuit connection material in many cases. In order to solve this problem, when the compounding amount of (meth)acrylate is reduced, although peeling at the interface between the circuit member and the circuit connection material can be suppressed, the adhesive strength is lowered, or the electrical connection between the opposing electrodes cannot be maintained. will do

The present invention was made in view of the problems of the prior art, and although it is a radical polymerization type, even when the circuit member is left in a high-temperature, high-humidity environment after connection, it is possible to sufficiently suppress the generation of peeling bubbles at the interface with the circuit member. An adhesive film comprising: a circuit connection material capable of maintaining sufficient connection reliability and maintaining sufficient connection reliability; a circuit connection structure fabricated using the circuit connection material; and a connection material layer comprising the circuit connection material; It aims to provide a body.

The present invention is a circuit connection material for electrically connecting two circuit members facing each other, comprising a thermoplastic resin, a radically polymerizable compound, a radical polymerization initiator and inorganic fine particles, wherein the content of the radically polymerizable compound is 40% by mass or more based on the total amount of the material, the content of the compound having a molecular weight of 1000 or less in the radically polymerizable compound is 15% by mass or less based on the total amount of the circuit connection material, and the content of the inorganic fine particles of the circuit connection material Provided is a circuit connection material containing at least a compound represented by the following formula (1) in an amount of 5 to 30% by mass based on the total amount.

[Wherein, 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, R ¹ , R ^{At least one of 2} and R ³ is an alkoxy group having 1 to 5 carbon atoms, R ⁴ is a (meth)acryloyl group, a vinyl group, an isocyanate group, an imidazole group, a mercapto group, an amino group, a methylamino group, a dimethylamino group, a benzylamino group , a phenylamino group, a cyclohexylamino group, a morpholino group, a piperazino group, a ureido group or a glycidyl group, and n represents an integer of 1 to 10]

Since the circuit connection material of this invention is a radical hardening type, circuit members can be adhere|attached at low temperature and in a short time. Moreover, according to the circuit connection material of this invention, even when a circuit member is left to stand in high-temperature, high-humidity environment after connection, generation|occurrence|production of the peeling bubble in the interface with a circuit member is fully suppressed, and sufficient connection reliability is maintained.

In the circuit connection material of this invention, the said thermoplastic resin may contain at least 1 sort(s) of resin whose glass transition temperature is 25 degreeC or more.

In the circuit connection material of the present invention, the average particle diameter of the inorganic fine particles may be less than 1 µm.

Electroconductive particle may be disperse|distributed to the circuit connection material of this invention. By disperse|distributing electroconductive particle, electroconductivity or anisotropic electroconductivity can be provided to a circuit connection material, and this circuit connection material can be used more suitably for the use etc. for connecting circuit members which have circuit electrodes. Moreover, by connecting with such a circuit connection material, the connection resistance between the connected circuit electrodes can fully be reduced.

That is, the present invention may be an anisotropic conductive adhesive containing the circuit connection material and conductive particles dispersed in the circuit connection material. In addition, electroconductive particle is not contained in "the whole quantity of a circuit connection material" in this specification.

The shape of the circuit connection material of this invention can be made into a film form. Such a circuit connection material is excellent in handleability.

In the present invention, at least one of the two circuit members may be a glass substrate. In addition, at least one of the two circuit members may be a flexible substrate. The circuit connection material of the present invention can be suitably used for connection of such circuit members.

The present invention also includes a pair of circuit members disposed oppositely and a cured product of the circuit connection material, and the circuit electrodes of each circuit member are electrically connected to each other through the pair of circuit members interposed therebetween. The circuit connection structure provided with the connection member which connects the said circuit member as possible is provided.

In the circuit connection structure of the present invention, since circuit members are adhered to each other by a connection member containing a cured product of the circuit connection material, peeling at the interface between the circuit member and the connection member even when left under high temperature and high humidity conditions Generation|occurrence|production of a bubble is fully suppressed, and sufficient connection reliability is maintained.

The present invention also provides an adhesive film comprising a film substrate and a film adhesive comprising the circuit connection material provided on one side of the film substrate. Since such an adhesive film is equipped with the film adhesive containing the said circuit connection material, it can utilize suitably for the connection of circuit members. Moreover, the adhesive film of this invention can be rolled up and stored in the form of a reel.

When a conventional circuit-connecting material is applied onto one side of a film substrate and rolled into a reel, the film-like adhesive may be transferred onto the other side of the film substrate, making it impossible to use effectively. In contrast, in the adhesive film of the present invention, since the film adhesive contains the circuit connection material, transfer of the film adhesive onto the other side of the film substrate is sufficiently suppressed even when it is wound on a reel.

The present invention also provides a rolled body formed by winding the adhesive film in the form of a reel. The rolled body of this invention can be used suitably for the connection of circuit members. Further, in the rolled body of the present invention, transfer of the film adhesive onto the other side of the film substrate is sufficiently suppressed.

The present invention can also be said to be a use of a composition containing a thermoplastic resin, a radically polymerizable compound, a radical polymerization initiator and inorganic fine particles as a circuit connection material for electrically connecting two circuit members facing each other. Here, the content of the radically polymerizable compound is 40% by mass or more based on the total amount of the composition, and the content of the compound having a molecular weight of 1000 or less in the radically polymerizable compound is 15% by mass or less based on the total amount of the composition, The content of the inorganic fine particles is 5 to 30% by mass based on the total amount of the composition, and the composition contains at least the compound represented by the formula (1).

Further, the present invention can also be said to be the use of a composition containing a thermoplastic resin, a radically polymerizable compound, a radical polymerization initiator and inorganic fine particles for the production of a circuit connection material for electrically connecting two circuit members facing each other. . Here, the content of the radically polymerizable compound is 40% by mass or more based on the total amount of the composition, and the content of the compound having a molecular weight of 1000 or less in the radically polymerizable compound is 15% by mass or less based on the total amount of the composition, The content of the inorganic fine particles is 5 to 30% by mass based on the total amount of the composition, and the composition contains at least the compound represented by the formula (1).

According to this use, a circuit that is radical polymerization type and capable of sufficiently suppressing the generation of peeling bubbles at the interface with the circuit member and maintaining sufficient connection reliability even when the circuit member is left under a high-temperature, high-humidity environment after connection. A connection material can be obtained.

According to the present invention, a radical polymerization type circuit capable of sufficiently suppressing the generation of peeling bubbles at the interface with the circuit member and maintaining sufficient connection reliability even when the circuit member is left under a high-temperature, high-humidity environment after connection An adhesive film comprising a connection material, a circuit connection structure produced using the circuit connection material, and a connection material layer containing the circuit connection material, and a rolled body of the adhesive film are provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows one Embodiment of the circuit connection material of this invention.
It is a schematic sectional drawing which shows one Embodiment of the connection structure of this invention.
3A to 3C are process diagrams showing a series of steps for connecting circuit members.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary. In addition, in a figure, the same code|symbol is attached|subjected to the same or substantially similar part, and overlapping description is abbreviate|omitted.

In addition, in this specification, (meth)acrylic acid shows acrylic acid or methacrylic acid corresponding thereto, (meth)acrylate means acrylate or methacrylate corresponding thereto, (meth)acryloyl group means an acryloyl group or a methacryloyl group.

The circuit connection material of this embodiment can be used suitably in order to electrically connect two circuit members which oppose each other, and a thermoplastic resin (Hereinafter, it is called "(a) component" in some cases), and radically polymerizable. A compound (hereinafter referred to as “component (b)” in some cases), a radical polymerization initiator (hereinafter referred to as “component (c)” in some cases), and inorganic fine particles (hereinafter referred to as “(d) component” in some cases) ingredients”).

In the present embodiment, the content of the component (b) is 40% by mass or more based on the total amount of the circuit connection material, and the content of the compound having a molecular weight of 1000 or less in the component (b) is 15% by mass based on the total amount of the circuit connection material. % or less, and content of (d) component is 5-30 mass %.

Further, the circuit connection material of the present embodiment contains a compound represented by the following general formula (1) (hereinafter, sometimes referred to as a "silane coupling agent").

<Formula 1>

In Formula 1, 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, R ¹ , R ^{At least one of 2} and R ³ is an alkoxy group having 1 to 5 carbon atoms, R ⁴ is a (meth)acryloyl group, a vinyl group, an isocyanate group, an imidazole group, a mercapto group, an amino group, a methylamino group, a dimethylamino group, a benzylamino group , a phenylamino group, a cyclohexylamino group, a morpholino group, a piperazino group, a ureido group or a glycidyl group, and n represents an integer of 1 to 10.

The silane coupling agent may be mix|blended with the circuit connection material as a part of the radically polymerizable compound of (b) component, and may be mix|blended with the circuit connection material as components other than (a)-(d) component. For example, when R ⁴ of Formula 1 is a (meth)acryloyl group or a vinyl group, the silane coupling agent is included in component (b).

Since the circuit connection member of this embodiment is a radical hardening type, it can adhere|attach circuit members at low temperature and in a short time. Moreover, according to the circuit connection material of this embodiment, even when a circuit member is left to stand in a high-temperature, high-humidity environment after connection, generation|occurrence|production of the peeling bubble at the interface with a circuit member is fully suppressed, and sufficient connection reliability is maintained.

(a) As a component, a well-known thermoplastic resin in particular can be used without restriction|limiting, You can also mix and use multiple types of well-known thermoplastic resin.

It is preferable that (a) component contains at least 1 sort(s) of resin whose glass transition temperature is 25 degreeC or more from a viewpoint which film-formability improves further. As such resin, polyimide resin, polyamide resin, phenoxy resin, poly(meth)acrylate resin, polyester resin, polyurethane resin, polyvinyl butyral resin, etc. are mentioned. Moreover, (a) component may contain resin whose glass transition temperature is less than 25 degreeC. In addition, the glass transition temperature of a thermoplastic resin can generally be calculated|required by the DSC method or the DVE method, and in this specification, the glass transition temperature shows the value calculated|required using the DSC method.

The thermoplastic resin of component (a) may contain a siloxane bond or a fluorine substituent (eg, a fluorine atom, a fluorinated alkyl group, or a fluorinated aryl group).

When two or more types of thermoplastic resins are mixed and used as the component (a), it is preferable that the thermoplastic resins to be mixed are completely compatible with each other, or microphase separation occurs and becomes cloudy.

The circuit connection material preferably contains, as component (a), at least one resin having a glass transition temperature of 25° C. or higher, and the resin preferably has a weight average molecular weight of 5.0×10 ³ to 2.0×10 ⁵ , It is more preferably 1.0×10 ⁴ to 1.5×10 ^{5 .}

Among the components (a), the resin having a glass transition temperature of 25° C. or higher has a weight average molecular weight of ^{less than 5.0×10 3} , a tendency for the adhesive strength of the circuit connection material to deteriorate, and a tendency for insufficient film formability to be obtained. When the average molecular weight exceeds 2.0×10 ⁵ , the compatibility with other components of the circuit connection material may be poor, and the fluidity of the circuit connection material may be reduced. On the other hand, according to resin whose weight average molecular weight is the said range, the fall of the adhesive force of a circuit connection material and the fall of fluidity|liquidity can fully be suppressed, and connection reliability can be improved further.

In addition, in this specification, a weight average molecular weight shows the weight average molecular weight of polystyrene conversion measured by GPC method.

The circuit connection material may contain a well-known rubber component as (a) component. By adding the rubber component, stress relaxation and improvement in adhesiveness can be expected. Specific examples of the rubber component include acrylic rubber, polyisoprene, polybutadiene, carboxyl-terminated polybutadiene, hydroxyl-terminated polybutadiene, 1,2-polybutadiene, carboxyl-terminated 1,2-polybutadiene, hydroxyl-terminated 1,2-polybutadiene, Styrene-butadiene rubber, hydroxyl-terminated styrene-butadiene rubber, carboxyl group, hydroxyl group, carboxylated nitrile rubber, hydroxyl-terminated poly(oxypropylene), alkoxysilyl-terminated poly(oxypropylene), poly(oxytetramethylene) glycol, polyolefin glycol and poly-ε-caprolactone.

The weight average molecular weight of the rubber component is preferably ^{2.0×10 5} to 1.0×10 ^{6 .} When the weight average molecular weight of the rubber component is ^{less than 2.0×10 5 , a} sufficient stress relaxation effect may not be obtained, and when ^{it exceeds 1.0×10 6} , the fluidity of the circuit connection material may decrease. That is, according to the rubber component whose weight average molecular weight exists in the said range, the further outstanding stress relaxation effect can be acquired, fully suppressing the fluidity|liquidity fall of a circuit connection material.

As a rubber component, the rubber component which has a cyano group or a carboxyl group which is a highly polar group in a side chain or a terminal from a viewpoint of adhesive improvement is preferable. In addition, a rubber component can be used individually by 1 type or in mixture of 2 or more types.

(a) It is preferable that it is 10-50 mass %, and, as for content of the thermoplastic resin with a glass transition temperature of 25 degreeC or more in a component, it is more preferable that it is 20-40 mass % on the basis of the whole quantity of a circuit connection material.

When content of the thermoplastic resin whose glass transition temperature is 25 degreeC or more among (a) components is less than 10 mass %, film formability may be inferior, and when it exceeds 50 mass %, the fluidity|liquidity of a circuit connection material may fall. On the other hand, if it is the said range, further excellent film formability and connection reliability can be acquired, fully suppressing the fall of the adhesive force of a circuit connection material, and the fall of fluidity|liquidity.

(b) As a component, a well-known radically polymerizable compound can be used. In addition, (b) component can be used individually by 1 type or in mixture of 2 or more types.

In this embodiment, content of (b) component is 40 mass % or more based on the whole quantity of a circuit connection material, Preferably it is 40-70 mass %, More preferably, it is 45-65 mass %.

Further, in the present embodiment, as the component (b), a compound having a molecular weight of more than 1000 (hereinafter, sometimes referred to as “component (b-1)”) is mainly used, and a compound having a molecular weight of 1000 or less (hereinafter referred to as “component (b-1)”) is mainly used. , the content of "(b-2) component" is sometimes called) is 15 mass % or less based on the whole quantity of a circuit connection material. (b-1) By making content of a component into 15 mass % or less, the effect of this invention mentioned above can be acquired remarkably.

(b-2) It is preferable that it is 15 mass % or less, and, as for content of a component, it is more preferable that it is 12.5 mass % or less. Moreover, content of (b-2) component may be 2.5 mass % or more, and may be 5 mass % or more.

(b-1) Content of a component is 25 mass % or more on the basis of the whole quantity of a circuit connection material, Preferably it is 30 mass % or more, More preferably, it is 35 mass % or more. Moreover, 55 mass % or less may be sufficient as content of (b-1) component, and 50 mass % or less may be sufficient as it.

(b-1) The molecular weight of a component becomes like this. Preferably it is 20000 or less, More preferably, it is 15000 or less. In addition, when (b-1) component has molecular weight distribution, the weight average molecular weight of (b-1) component can be regarded as the molecular weight of (b-1).

In the present embodiment, the ratio (mass ratio) C ₂ /C _{1 of the content C 2} of the component (b-2) to _{the content C 1} of the component (b-1) is preferably 0 to 0.6, more preferably Preferably it is 0.05-0.4, More preferably, it is 0.075-0.35.

(b-1) As a component, For example, oligomers, such as an epoxy (meth)acrylate oligomer, a urethane (meth)acrylate oligomer, a polyether (meth)acrylate oligomer, and a polyester (meth)acrylate oligomer; Trimethylolpropane tri(meth)acrylate, polyethylene glycol di(meth)acrylate, polyalkylene glycol di(meth)acrylate, dicyclopentenyl(meth)acrylate, dicyclopentenyloxyethyl(meth)acryl Rate, neopentyl glycol di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, isocyanuric acid-modified bifunctional (meth) acrylate, isocyanuric acid-modified trifunctional (meth) acrylate, bisphenol Epoxy (meth)acrylate obtained by adding (meth)acrylic acid to the glycidyl group of fluorenediglycidyl ether, or a compound obtained by adding ethylene glycol and/or propylene glycol to the glycidyl group of bisphenol fluorenediglycidyl ether Polyfunctional (meth)acrylates, such as the compound which introduce|transduced the (meth)acryloyloxy group to it, are mentioned. These compounds can be used individually by 1 type or in mixture of 2 or more types.

In addition, as a component (b-2), pentaerythritol (meth)acrylate, 2-cyanoethyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclo Pentenyloxyethyl (meth) acrylate, 2-(2-ethoxyethoxy) ethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n- Hexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, isobornyl (meth) acrylate, isodecyl (meth) acrylate, isooctyl (meth) acrylic Rate, n-lauryl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2- (meth) acrylic Royloxyethyl phosphate, N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, (meth)acryloylmorpholine, etc. are mentioned. These compounds can be used individually by 1 type or in mixture of 2 or more types.

The circuit connection material preferably contains at least one compound having two or more (meth)acryloyl groups in the molecule as the component (b), and as the component (b-1), two or more (meth)acryloyl groups in the molecule. ) It is more preferable to contain at least 1 sort(s) of the compound which has an acryloyl group.

As the component (b), a compound having a (meth)acryloyl group is preferable. As the component (b), a compound having a functional group that is polymerized by active radicals such as an allyl group, a maleimide group and a vinyl group can also be used. Specific examples of the component (b) include N-vinylimidazole, N-vinylpyridine, N-vinylpyrrolidone, N-vinylformamide, N-vinylcaprolactam, and 4,4'-vinylidene bis(N ,N-dimethylaniline), N-vinylacetamide, N,N-dimethylacrylamide, N-isopropylacrylamide, N,N-diethylacrylamide, methylolacrylamide, 4,4'-diphenylmethane Bismaleimide, 3,3'-dimethyl-5,5'-4,4'-diphenylmethanebismaleimide, 1,6-bismaleimide-(2,2,4-trimethyl)hexane, etc. are mentioned. have.

Moreover, the circuit connection material may contain the radically polymerizable compound which has a phosphoric acid ester structure as (b) component. As a radically polymerizable compound which has a phosphoric acid ester structure, the radically polymerizable compound which has a phosphoric acid ester structure represented by following General formula (2) - 4 is mentioned, for example. By mix|blending such a compound, the adhesive strength with respect to the surface of inorganic substances, such as a metal, improves further, and the circuit connection material which is more effective for adhesion|attachment of circuit electrodes is obtained.

In formula (2), R ⁵ represents a (meth)acryloyloxy group, R ⁶ represents a hydrogen atom or a methyl group, and w and x each independently represent an integer of 1 to 8. In the formula, R ⁵ , R ⁶ , w, and x may be the same or different from each other.

In Formula 3, R ⁷ represents a (meth)acryloyloxy group, and y and z each independently represent an integer of 1 to 8. In the formula, R ⁷ , y , and z may each be the same or different.

In formula (4), R ⁸ represents a (meth)acryloyloxy group, R ⁹ represents a hydrogen atom or a methyl group, and a and b each independently represent an integer of 1 to 8.

Specific examples of the radically polymerizable compound having a phosphoric acid ester structure include acid phosphooxyethyl methacrylate, acid phosphooxyethyl acrylate, acid phosphooxypropyl methacrylate, and acid phosphooxypolyoxyethylene glycol monomethacrylic. acid phosphooxypolyoxypropylene glycol monomethacrylate, 2,2'-di(meth)acryloyloxydiethyl phosphate, EO-modified phosphoric acid dimethacrylate, phosphoric acid-modified epoxy acrylate, vinyl phosphate, etc. can

It is preferable that it is 0.01-10 mass % on the basis of the whole quantity of a circuit connection material, and, as for content of the radically polymerizable compound which has a phosphoric acid ester structure, it is more preferable that it is 0.5-5 mass %.

Moreover, as a radically polymerizable compound which has a phosphoric acid ester structure, the compound which made phosphoric anhydride and 2-hydroxyethyl (meth)acrylate react can also be used. Examples of the radically polymerizable compound having such a phosphoric acid ester structure include mono(2-methacryloyloxyethyl)acid phosphate, di(2-methacryloyloxyethyl)acid phosphate, and the like. In addition, the compound which has a phosphoric acid ester structure may be used individually by 1 type, or may mix and use 2 or more types.

The radically polymerizable compound having a phosphoric acid ester structure may be a component (b-1) or a component (b-2), and is preferably a component (b-2).

The circuit connection material may further contain, as the component (b), one having radical polymerizability among the silane coupling agents represented by the formula (1) as described above.

(c) As a radical polymerization initiator of a component, the compound which decomposes|disassembles by heating and generate|occur|produces a free radical is mentioned, for example, Well-known compounds, such as a peroxide and an azo compound, can be used.

(c) From the viewpoint of having both stability, reactivity and compatibility, a peroxide having a half-life temperature of 90 to 175°C for 1 minute and a molecular weight of 180 to 1000 can be suitably used as the component (c). Here, "1 minute half-life temperature" refers to the temperature at which the half-life becomes 1 minute, and "half-life" refers to the time until the concentration of the compound decreases to half of the initial value.

(c) Specific examples of the component include 1,1,3,3-tetramethylbutylperoxyneodecanoate, di(4-t-butylcyclohexyl)peroxydicarbonate, di(2-ethylhexyl)per Oxydicarbonate, cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, dilauroyl peroxide, 1-cyclohexyl-1-methylethylperoxyneo Decanoate, t-hexylperoxyneodecanoate, t-butylperoxyneodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexa Noate, 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate , t-butylperoxyneoheptanoate, t-amylperoxy-2-ethylhexanoate, di-t-butylperoxyhexahydroterephthalate, t-amylperoxy-3,5,5-trimethylhexanoate Noate, 3-hydroxy-1,1-dimethylbutylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, t-amylperoxyneodecano ate, t-amylperoxy-2-ethylhexanoate, 3-methylbenzoylperoxide, 4-methylbenzoylperoxide, di(3-methylbenzoyl)peroxide, dibenzoylperoxide, di(4-methylbenzoyl) ) Peroxide, 2,2'-azobis-2,4-dimethylvaleronitrile, 1,1'-azobis (1-acetoxy-1-phenylethane), 2,2'-azobisisobutyro Nitrile, 2,2'-azobis(2-methylbutyronitrile), dimethyl-2,2'-azobisisobutyronitrile, 4,4'-azobis(4-cyanovaleric acid), 1, 1'-azobis(1-cyclohexanecarbonitrile), 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-ethylhexyl monocarbonate, t-hexylperoxy Benzoate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t-butylperoxybenzoate, dibutylperoxytrimethyladipate, t-amylperoxynormaloctoate, t-amylper Oxyisononanoate, t-amylperoxybenzoate, etc. are mentioned. In addition, (c) component may be used individually by 1 type, and may mix and use 2 or more types of compounds.

(c) As a component, the compound which generate|occur|produces a radical by light irradiation (for example, light irradiation with a wavelength of 150 nm - 750 nm) can also be used.

As such a compound, for example, Photoinitiation, Photopolymerization, and Photocuring, J.-P. The ?-acetoaminophenone derivatives and phosphine oxide derivatives described in Fouassier, Hanser Publishers (1995), p17 to p35 are more preferable because of their high sensitivity to light irradiation. These compounds may be used individually by 1 type, and may be used in mixture with the said peroxide or azo compound.

In order to suppress corrosion of the circuit electrode of a circuit member, it is preferable that it is 10000 mass ppm or less, respectively, and, as for the quantity of the chlorine ion and organic acid contained in (c) component, it is more preferable that it is 5000 mass ppm or less. Moreover, since corrosion of a circuit electrode is fully suppressed as it is below this upper limit, the quantity of the chlorine ion and organic acid contained in (c) component may be 500 mass ppm or more.

Moreover, as for (c) component, it is preferable that the mass retention after 24 hours open standing under room temperature (25 degreeC) and normal pressure is 20 mass % or more. According to the component (c) having such a mass retention rate, the storage stability of the circuit connection material is further improved. In addition, mass retention can be measured by measuring the weight before and behind leaving-to-stand.

(c) It is preferable that it is 0.1-30 mass %, and, as for content of a component, it is more preferable that it is 1-20 mass % based on the whole quantity of a circuit connection material. (c) When content of a component is the said range, the reaction rate and long pot life for obtaining sufficient adhesive force can be compatible at a higher level.

As the inorganic fine particles of the component (d), known inorganic fine particles can be used without particular limitation. (d) As a component, metal oxide microparticles|fine-particles, such as silica microparticles|fine-particles, alumina microparticles|fine-particles, silica-alumina microparticles|fine-particles, titania microparticles|fine-particles, and zirconia microparticles|fine-particles, are mentioned, for example. In addition, (d) component can be used individually by 1 type or in mixture of 2 or more types.

(d) It is preferable that it is less than 1 micrometer, and, as for the average particle diameter of a component, it is more preferable that it is 0.1-0.5 micrometer. In addition, the average particle diameter here is a major-axis direction mode diameter when it exists in a circuit connection material. (d) It is preferable that it is 100 nm or less, and, as for the average primary particle diameter of a component, it is more preferable that it is 10-30 nm. In addition, in this specification, an average particle diameter shows the value measured by image analysis.

(d) As a component, since it is excellent in dispersibility, the microparticles|fine-particles which modified the surface with organic groups can be used suitably. As an organic group, a dimethylsiloxane group, a diphenylsiloxane group, etc. are mentioned, for example.

(d) It is preferable that it is 5-30 mass % on the basis of the whole quantity of a circuit connection material, and, as for content of a component, it is more preferable that it is 10-20 mass %. (d) The connection resistance between circuit electrodes to be connected as content of a component is the said range can be reduced further, and the effect of this invention is exhibited still remarkably.

The silane coupling agent represented by the formula (1) may be blended into the circuit connection material as a part of component (b) as described above, or may be blended into the circuit connection material as a component other than the components (a) to (d). have.

<Formula 1>

In Formula 1, 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, R ¹ , R ^{At least one of 2} and R ³ is an alkoxy group having 1 to 5 carbon atoms, R ⁴ is a (meth)acryloyl group, a vinyl group, an isocyanate group, an imidazole group, a mercapto group, an amino group, a methylamino group, a dimethylamino group, a benzylamino group , a phenylamino group, a cyclohexylamino group, a morpholino group, a piperazino group, a ureido group or a glycidyl group, and n represents an integer of 1 to 10.

When R ⁴ of Formula 1 is a (meth)acryloyl group or a vinyl group, the silane coupling agent is included in component (b).

R ¹ , R ^{2 ,} and R ³ are preferably a methyl group, an ethyl group, a methoxy group or an ethoxy group, and more preferably a methoxy group or an ethoxy group.

It is preferable that they are a (meth)acryloyl group, a glycidyl group, a mercapto group, or a vinyl group, and, as for R<^{4>, it is more preferable that they are a (meth)acryloyl group or a glycidyl group.}

It is preferable that it is 0.1-10 mass % on the basis of the whole quantity of a circuit connection material, and, as for content of a silane coupling agent, it is more preferable that it is 0.25-5 mass %. When content of a silane coupling agent is the said range, generation|occurrence|production of the peeling bubble in the interface of a circuit member and a connection member can be suppressed further remarkably, and a longer pot life is securable.

The circuit connection material of this embodiment may contain components other than the above. For example, you may add a stabilizer to a circuit connection material for reasons, such as control of a curing rate and provision of storage stability. Examples of the stabilizer include quinone derivatives such as benzoquinone and hydroquinone; phenol derivatives such as 4-methoxyphenol and 4-t-butylcatechol; aminooxyl derivatives such as 2,2,6,6-tetramethylpiperidine-1-oxyl and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl; Hindered amine derivatives, such as tetramethylpiperidyl methacrylate, etc. can be used suitably.

When the circuit connection material contains a stabilizer, the content of the stabilizer is preferably 0.01 to 15 mass%, more preferably 0.05 to 10 mass%, based on the total amount of the circuit connection material. When content of a stabilizer is less than 0.01 mass %, the addition effect may not fully be acquired, and when it exceeds 15 mass %, a polymerization reaction may be inhibited and low-temperature rapid hardening may be inferior.

Moreover, you may add organic microparticles|fine-particles to the circuit connection material of this embodiment for the purpose of stress relaxation and the improvement of heat resistance. As the organic fine particles, known organic fine particles can be used without particular limitation.

As organic microparticles|fine-particles, silicone microparticles|fine-particles, methacrylate-butadiene-styrene microparticles|fine-particles, acryl- silicone microparticles|fine-particles, polyamide microparticles|fine-particles, polyimide microparticles|fine-particles, etc. are mentioned, for example. These organic fine particles may have a uniform structure or a core-shell type structure.

When the circuit connection material contains organic fine particles, the content of the organic fine particles is preferably 1.5 to 20 mass%, more preferably 2 to 15 mass%, based on the total amount of the circuit connection material.

Electroconductive particle may be disperse|distributed to the circuit connection material of this embodiment. Thereby, electroconductivity or anisotropic electroconductivity can be provided to a circuit connection material, and such a circuit connection material can be used more suitably for the connection use etc. of circuit members which have circuit electrodes. Moreover, by connecting with such a circuit connection material, the connection resistance between the connected circuit electrodes can fully be reduced.

That is, the present invention may be an anisotropic conductive adhesive containing a circuit connection material and conductive particles dispersed in the circuit connection material. In addition, electroconductive particle is not contained in "the whole quantity of a circuit connection material" in this specification.

As electroconductive particle, the metal particle, carbon particle, etc. in which Au, Ag, Pd, Ni, Cu, a solder, etc. contain a metal are mentioned. Further, the conductive particles may be those in which particles containing a non-conductive material such as glass, ceramic, or plastic are used as a nuclide, and the nuclide is coated with a conductive material such as metal, metal particles, or carbon.

Moreover, as electroconductive particle, a heat fusion metal particle is preferable. Since such electroconductive particle has deformability by heating and pressurization, when connecting circuit members, the contact area of electroconductive particle and an electrode increases, and there exists a tendency for the connection reliability between circuit members to improve.

It is preferable to set it as 0.1-30 volume% with respect to the total volume of an anisotropic conductive adhesive, and, as for the compounding quantity of electroconductive particle, it is more preferable to set it as 0.1-10 volume%. If the compounding quantity of electroconductive particle is less than 0.1 volume%, there exists a tendency for electroconductivity to be inferior, and when it exceeds 30 volume%, there exists a tendency for the short circuit between circuit electrodes to become easy to generate|occur|produce. In addition, the compounding quantity of electroconductive particle is determined based on the volume in 23 degreeC by each component of the circuit connection material before hardening. The volume of each component can be calculated|required by converting mass into volume using specific gravity. In addition, without dissolving or swelling the component whose volume is to be measured, a suitable solvent (water, alcohol, etc.) that can permeate the component is placed in a measuring cylinder, etc., and the component to be measured is added thereto to increase the volume can also be found as the volume of the component.

The circuit connection material of this embodiment can be manufactured by mixing each component mentioned above without using a solvent. In addition, each of the above-mentioned components can also be prepared by mixing with a solvent capable of dissolving or dispersing each of the above-mentioned components.

The circuit connection material of this embodiment can be used as a film form. By setting it as the shape of a film, the handleability of a circuit connection material becomes very favorable.

Specifically, for example, by applying a solution prepared by adding a solvent or the like to a circuit connection material as needed on a releasable substrate such as a fluororesin film, polyethylene terephthalate film, or release paper, and then removing the solvent. , a film-form circuit connection material (hereinafter, sometimes referred to as “film-like adhesive”) can be obtained. In addition, a film adhesive can also be obtained by impregnating a base material, such as a nonwoven fabric, with the solution prepared by adding a solvent etc. to a circuit connection material as needed, placing it on a peelable base material, and removing a solvent. Moreover, electroconductive particle can be disperse|distributed to a film adhesive by mix|blending electroconductive particle at the time of mixing.

As a solvent, methyl ethyl ketone and toluene can be used suitably, for example.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows one Embodiment of the circuit connection material of this invention. The film adhesive 1 shown in FIG. 1 is formed by shape|molding the said circuit connection material into a film shape. The film adhesive 1 is easy to handle and can be easily installed on an adherend. Therefore, according to the film adhesive 1, a connection operation can be performed easily.

The film adhesive 1 may have a multilayer structure (not shown) containing two or more types of layers. In addition, in the film adhesive 1, electroconductive particle (not shown) may be disperse|distributed. The film-form adhesive in which electroconductive particle was disperse|distributed can be used suitably as an anisotropically conductive film-form adhesive agent. That is, an anisotropically conductive film-like adhesive agent containing the said circuit connection material and electroconductive particle may be sufficient as this invention.

As a connection method of the to-be-adhered body using the circuit connection material (for example, the film adhesive 1) of this embodiment, the connection method which used heating and pressurization together is mentioned, for example. In this method, the heating temperature is preferably 100 to 250°C. Further, the pressure is not particularly limited as long as it does not damage the adherend, but is generally preferably 0.1 to 10 MPa. It is preferable to perform this heating and pressurization in the range of 0.5 second - 120 second. Moreover, according to the said circuit connection material, to-be-adhered bodies can fully adhere|attach each other by performing heating and pressurization for 10 second under the conditions of a heating temperature of 150-200 degreeC and a pressure of 3 MPa, for example.

The circuit connection material of the present embodiment can be suitably used as an adhesive for different types of adherends having different coefficients of thermal expansion. Specifically, for example, as a circuit connection material represented by an anisotropic conductive adhesive, silver paste, silver film, etc., or as a semiconductor element adhesive material represented by an elastomer for CSP, underfill material for CSP, LOC tape, etc. Can be used.

The circuit connection material of this embodiment may be formed in the form of a film on one side of a film base material.

That is, the present invention may be an adhesive film comprising a film substrate and a film adhesive provided on one side of the film substrate and containing the circuit connection material. Such an adhesive film can be suitably used as the above-mentioned film adhesive by peeling a film base material.

In the adhesive film, since the film adhesive contains the circuit connection material having the above-described specific configuration, even when wound on a reel so that the other side of the film substrate and the film adhesive come into contact, the film on the other side of the film substrate Transfer of the upper adhesive is sufficiently suppressed.

When the same rolled body is produced with the conventional circuit connection material, the circuit connection material may seep out from between the film substrates. Even when it rolls up in the form of , reel, the seepage of the film adhesive from between film-form base materials is fully suppressed. Therefore, the adhesive film can be suitably stored as a rolled body wound up in the shape of a reel, and it is further excellent in handleability.

Examples of the film substrate include polyethylene terephthalate, polycarbonate, and polypropylene.

The adhesive film can be, for example, 5 mm or less in width (preferably 0.5 to 5.0 mm) and 1 m or more in length (preferably 10 to 500 m). Since it is preferable to roll up and store the adhesive film of such a size in the form of a reel, the effect mentioned above becomes especially effective.

The adhesive film may further be equipped with the protective film provided on the film adhesive. Since a protective film needs to peel before connection of a to-be-adhered body, it is preferable that it is excellent in peelability.

Hereinafter, an example in the case of connecting the circuit members in which the circuit electrode was formed on the main surface of a circuit board using the circuit connection material of this embodiment is demonstrated. In the following description, the case where the conductive particles are dispersed in the circuit connection material to form an anisotropic conductive adhesive is exemplified. have.

By arranging an anisotropic conductive adhesive between opposing circuit electrodes on a circuit board and heating and pressing, electrical connection between opposing circuit electrodes and adhesion between circuit boards can be performed to connect circuit members.

As a circuit board, For example, a glass substrate; The flexible substrate in which a polyimide, polyethylene terephthalate, polycarbonate, etc. contain an organic substance is mentioned. Here, as a circuit board, when one is a glass substrate and the other is a flexible substrate, the effect of this invention is large especially. Moreover, as a circuit board, the board|substrate which combined inorganic substances, such as glass/epoxy, and an organic substance, can also be used.

2 : is a schematic sectional drawing which shows one Embodiment of the circuit connection structure of this invention. The circuit connection structure shown in FIG. 2 is provided with the 1st circuit member 20 and the 2nd circuit member 30 which oppose each other, The 1st circuit member 20 and the 2nd circuit member 30 are interposed. A connecting member 10 for connecting them is provided.

The 1st circuit member 20 is equipped with the circuit board (1st circuit board) 21, and the circuit electrode (1st circuit electrode) 22 formed on the main surface 21a of the circuit board 21. . In addition, an insulating layer (not shown) may be formed on the main surface 21a of the circuit board 21 in some cases.

Meanwhile, the second circuit member 30 includes a circuit board (second circuit board) 31 and a circuit electrode (second circuit electrode) 32 formed on the main surface 31a of the circuit board 31 . are doing In addition, an insulating layer (not shown) may be formed also on the main surface 31a of the circuit board 31 in some cases.

The first and second circuit members 20 and 30 are not particularly limited as long as electrodes that require electrical connection are formed. Specific examples include glass or plastic substrates, printed wiring boards, ceramic wiring boards, flexible wiring boards, semiconductor silicon chips, etc. having electrodes formed with ITO, IZO, etc. used in liquid crystal displays, and these are used in combination as needed. do. In this way, in this embodiment, like printed circuit boards or polyimide, as well as a material including an organic material, copper, metal such as aluminum or ITO (indium tin oxide), silicon nitride (SiN _x), silicon dioxide (SiO _2), etc. It is possible to use circuit members having various surface states, such as inorganic materials of

The connecting member 10 contains an insulating material 11 and conductive particles 7 . The electroconductive particle 7 is arrange|positioned not only between the circuit electrode 22 and the circuit electrode 32 which oppose but also between main surfaces 21a, 31a comrades. In this circuit connection structure, the circuit electrodes 22 and 32 are electrically connected via the electroconductive particle 7 . That is, the electroconductive particle 7 is contacting both the circuit electrodes 22 and 32 directly.

Here, the electroconductive particle 7 is the electroconductive particle demonstrated previously, and the insulating substance 11 is hardened|cured material of the said circuit connection material.

In this circuit connection structure, the circuit electrode 22 and the circuit electrode 32 which oppose are electrically connected via the electroconductive particle 7 as mentioned above. For this reason, the connection resistance between the circuit electrodes 22 and 32 is fully reduced. Therefore, the current flow between the circuit electrodes 22 and 32 can be made smooth, and the function of the circuit can be fully exhibited. In addition, when the connection member 10 does not contain the electroconductive particle 7, the circuit electrode 22 and the circuit electrode 32 are electrically connected by direct contact.

Since the connection member 10 is composed of the cured product of the circuit connection material and conductive particles, the adhesive strength of the connection member 10 to the circuit member 20 or 30 is sufficiently high, and the reliability test (high temperature and high humidity test) ), stable performance (good adhesive strength and connection resistance) can be maintained.

Next, an example of the manufacturing method of the circuit connection structure mentioned above is demonstrated, referring FIG. First, the 1st circuit member 20 and the film adhesive 40 mentioned above are prepared (refer FIG.3(a)). The film adhesive 40 is formed by shape|molding the circuit connection material in which the electroconductive particle was disperse|distributed to the film form, and contains the circuit connection material 5 and the electroconductive particle 7 . Further, even when the conductive particles 7 are not dispersed in the film adhesive 40 (that is, when the film adhesive 40 contains the circuit connection material 5), the film adhesive is an insulating adhesive. It can be used for anisotropic conductive bonding as an anisotropic conductive adhesive, and the circuit connection material is sometimes called NCP (Non-Conductive Paste). In addition, when the conductive particles 7 are dispersed in the circuit connection material 5, the material is sometimes called ACP (Anisotropic Conductive Paste).

It is preferable that the thickness of the film adhesive 40 is 6-50 micrometers. When the thickness of the film adhesive 40 is less than 6 micrometers, there exists a tendency for the circuit connection material 5 to become insufficient filling between the circuit electrodes 22 and 32. On the other hand, when it exceeds 50 micrometers, the circuit connection material 5 between the circuit electrodes 22 and 32 cannot fully be completely excluded, and there exists a tendency for the electrical conduction ensuring between the circuit electrodes 22 and 32 to become difficult.

Next, the film adhesive 40 is mounted on the surface in which the circuit electrode 22 of the 1st circuit member 20 is formed. In addition, when the film adhesive 40 is affixed on a support body (not shown), the film adhesive 40 side is made to face the 1st circuit member 20, and the 1st circuit member 20 put it on top At this time, the film adhesive 40 is in the form of a film, and handling is easy. For this reason, the film adhesive 40 can be easily interposed between the 1st circuit member 20 and the 2nd circuit member 30, and the 1st circuit member 20 and the 2nd circuit member 30 are Connection work can be performed easily.

And the film adhesive 40 is pressed in the arrow A and B directions of Fig.3 (a), and the film adhesive 40 is temporarily connected to the 1st circuit member 20 (FIG.3(b)) Reference). At this time, you may pressurize, heating. However, the heating temperature is set to a temperature lower than the temperature at which the film adhesive 40 (circuit connection material 5 constituting the film adhesive 40) does not cure.

Then, as shown in Fig. 3(c), the second circuit member 30 is placed on the film adhesive 40 with the second circuit electrode 32 facing the first circuit member 20. put on In addition, when the film adhesive 40 is adhered on a support body (for example, the above-mentioned film-form base material (not shown)), after peeling the support body, the 2nd circuit member 30 is attached to the film adhesive ( 40) Put it on top. At this time, the second circuit member 30 may be temporarily fixed by aligning the first and second circuit electrodes 22 and 23 to face each other, and then heating and pressing from above the second circuit member 30 . By doing in this way, the position shift of the electrode at the time of the following main connection can be suppressed. The heating temperature at the time of temporary fixing is set to a temperature lower than the temperature at which the circuit connection material 5 in the film adhesive 40 does not cure, and for shortening throughput, it is preferable that the time from alignment to completion of temporary fixing is 5 seconds or less. do.

And while heating the film adhesive 40, it presses through the 1st and 2nd circuit members 20 and 30 in the arrow A and B directions of FIG.3(c). The heating temperature at this time is set as the temperature at which the polymerization reaction can be started. In this way, the film adhesive 40 is hardened and this connection is performed, and the circuit connection structure as shown in FIG. 2 is obtained.

Here, as described above, the connection conditions are preferably a heating temperature of 100 to 250° C., a pressure of 0.1 to 10 MPa, and a connection time of 0.5 seconds to 120 seconds. These conditions are suitably selected according to the use to be used, a circuit connection material, and a circuit member, and you may perform post-curing as needed.

In the circuit connection structure obtained by manufacturing a circuit connection structure as mentioned above, it becomes possible to make the electroconductive particle 7 contact both of the circuit electrodes 22 and 32 which oppose, and the circuit electrodes 22 and 32 The connection resistance between them can be sufficiently reduced.

Further, by heating the film adhesive 40, the circuit connection material 5 is cured to form an insulating material 11 in a state where the distance between the circuit electrode 22 and the circuit electrode 32 is sufficiently small, The first circuit member 20 and the second circuit member 30 are firmly connected through the connecting member 10 . That is, in the circuit connection structure obtained, since the connection member 10 is provided with the insulating material 11 containing the circuit connection material described above, the connection member 10 is adhered to the circuit member 20 or 30 . While the intensity|strength becomes high enough, the connection resistance between the electrically connected circuit electrodes can fully be reduced. In addition, even when placed in a high-temperature, high-humidity environment for a long period of time, the generation of peeling bubbles at the interface between the circuit members 20 and 30 and the connection member 10 can be sufficiently suppressed, and the adhesive strength decreases and the connection resistance decreases. growth can be sufficiently suppressed.

As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to the said embodiment.

For example, the present invention is the use of a composition containing the thermoplastic resin, the radical polymerizable compound, the radical polymerization initiator and the inorganic fine particles as a circuit connection material for electrically connecting two circuit members facing each other. You may. The present invention also relates to a use of a composition containing the thermoplastic resin, the radically polymerizable compound, the radical polymerization initiator and the inorganic fine particles for producing a circuit connection material for electrically connecting two circuit members facing each other. You might say

In this use, the content of the radically polymerizable compound is 40% by mass or more based on the total amount of the composition, and the content of the compound having a molecular weight of 1000 or less in the radically polymerizable compound is 15% by mass based on the total amount of the composition Below, the content of the inorganic fine particles is 5 to 30% by mass based on the total amount of the composition, and the composition contains at least the compound represented by the formula (1).

According to this use, although it is a radical polymerization type, even when the circuit member is left under a high-temperature, high-humidity environment after connection, the generation of peeling bubbles at the interface with the circuit member can be sufficiently suppressed and sufficient connection reliability can be maintained. The circuit connection material described above can be obtained.

Example

Hereinafter, the present invention will be described in more detail by way of Examples, but the present invention is not limited to Examples.

(Production Example 1: Synthesis of thermoplastic resin)

To a separable flask equipped with a reflux condenser, a thermometer and a stirrer, 1000 parts by mass of polypropylene glycol (Mn=2000) as a diol having an ether bond and 4000 parts by mass of methyl ethyl ketone as a solvent were added, followed by stirring at 40° C. for 30 minutes. . After heating up this solution to 70 degreeC, 1 mass part of dimethyl tin laurate is added as a catalyst, Then, with respect to this solution, 125 mass parts of 4, 4- diphenylmethane diisocyanate as a diisocyanate compound methyl ethyl ketone 125 The solution dissolved in the mass part was dripped over 1 hour.

Then, stirring was continued at 70 degreeC until the absorption peak of NCO (isocyanate group) was not seen with an infrared spectrophotometer, and the methyl ethyl ketone solution of a polyurethane resin was obtained. This solution was adjusted so that solid content concentration might be set to 30 mass %, and it was used by the Example and the comparative example.

The weight average molecular weight of the obtained polyurethane resin in terms of polystyrene was 320000 as a result of the measurement by GPC. The analysis conditions of GPC are shown in Table 1 below.

(Preparation Example 2: Synthesis of radically polymerizable compound)

To a 2-liter four-neck flask equipped with a thermometer, a stirrer, an inert gas inlet and a reflux condenser, 4000 parts by mass of polycarbonate diol (manufactured by Aldrich, number average molecular weight 2000), 238 parts by mass of 2-hydroxyethyl acrylate , 0.49 parts by mass of hydroquinone monomethyl ether, and 4.9 parts by mass of a tin-based catalyst were put in, heated to 70°C, and 666 parts by mass of IPDI (isophorone diisocyanate) was uniformly added dropwise over 3 hours and reacted. After completion of the dropwise addition, the reaction was continued for 15 hours, the time when NCO% (quantity of the isocyanate group with respect to the urethane group) became 0.2% or less was set as completion|finish of reaction, and the urethane acrylate was obtained. As a result of the analysis by GPC, the weight average molecular weight of the obtained urethane acrylate was 8500. In addition, GPC analysis was performed under the conditions of Table 1.

(Production Example 3: Preparation of conductive particles)

A layer containing nickel having a thickness of 0.2 mu m was provided on the surface of the polystyrene particles, and then a layer containing gold was formed so as to have a thickness of 0.04 mu m on the surface of the layer containing nickel. In this way, the electroconductive particle with an average particle diameter of 5 micrometers was produced.

(Examples 1 to 6 and Comparative Examples 1 to 4)

(a) As the thermoplastic resin of the component, 40 g of phenoxy resin (PKHC, trade name manufactured by Union Carbite Co., Ltd., weight average molecular weight (45000, indicated as "PKHC" in the table)) is dissolved in 60 g of methyl ethyl ketone, a solution having a solid content concentration of 40% by mass; And the solution of 30 mass % of solid content concentration of the polyurethane resin (indicated by "PU" in a table|surface) obtained by manufacture example 1 was used.

In addition, as a radically polymerizable compound of (b) component, the urethane acrylate (represented as "UA" in the table|surface) obtained in Production Example 2, cyclohexyl acrylate (made by Toagosei Co., Ltd., shown as "CHA" in the table) ), 2-(meth)acryloyloxyethyl phosphate (light ester P-2M, manufactured by Kyoesha Corporation, as "P-2M" in the table), and 3-methacryloxypropyltrimethoxy Silane (KBM503, manufactured by Shin-Etsu Chemical Co., Ltd., trade name, silane coupling agent, indicated as "KBM" in the table) was used.

In addition, as a radical polymerization initiator of (c) component, t-hexylperoxy-2-ethylhexanoate (Perhexyl O, the Yushi Sehin Co., Ltd. brand name, it shows as "peroxide" in the table|surface) was used.

Further, as the inorganic fine particles of the component (d), 10 g of R711 (trade name manufactured by Nippon Aerosil Co., Ltd., indicated as "R711" in the table) is dispersed in a mixed solvent of 45 g of toluene and 45 g of ethyl acetate, and a 10% by mass solution was used as

Each of the above components was blended so as to have a solid content weight ratio shown in Table 2, and then, the conductive particles obtained in Production Example 3 were blended and dispersed in an amount of 1.5% by volume with respect to the total volume of the adhesive component to obtain a coating solution. The obtained coating liquid was apply|coated to a 50-micrometer-thick polyethylene terephthalate (PET) film using the coating apparatus, 70 degreeC, hot-air drying for 10 minutes was performed, and the 16-micrometer-thick film adhesive was obtained.

Content of the radically polymerizable compound in the film adhesive of each Example and comparative example, content of the radically polymerizable compound ((b-1) component) whose molecular weight exceeds 1000, the radically polymerizable compound ((b) with molecular weight 1000 or less -2) The content of the component) and the content of the inorganic fine particles were as described in Table 3, calculated from the respective compounding amounts (all are mass % based on the total amount of the circuit connection material (components other than the conductive particles of the film adhesive)). In addition, 3-methacryloxypropyl trimethoxysilane of a silane coupling agent is contained in (b-2) component.

(Examples 6 to 10 and Comparative Examples 6 to 10)

The bonded structures of Examples 6-10 and Comparative Examples 6-10 were produced using each film adhesive of Examples 1-5 and Comparative Examples 1-5.

Specifically, the film adhesive was transferred to a glass substrate (thickness 1.1 mm) on which a thin film of indium oxide (ITO) having a thickness of 0.2 μm was formed under conditions of 1 MPa and 2 seconds at a temperature of 70°C. Next, this glass substrate and a flexible circuit board (FPC substrate) in which 500 copper circuits having a line width of 75 μm, a pitch of 150 μm and a thickness of 18 μm were wired on polyimide with an epoxy resin adhesive were placed to face each other through a film adhesive, , a thermocompression bonding apparatus (heating method: constant heat type, manufactured by Toray Engineering, Ltd.) was used to heat and press at a temperature of 160°C at 3 MPa for 10 seconds. Thereby, the connection body (circuit connection structure) in which the FPC board|substrate and the glass substrate (ITO board|substrate) were connected by the hardened|cured material (connection member) of a film adhesive over 2 mm was obtained.

(Evaluation of circuit connection structure 1: evaluation of initial connection resistance)

About the circuit connection structure obtained by the Example and the comparative example, the resistance value (connection resistance) between adjacent circuits was measured with a multimeter, respectively. The average of 37 resistance points between adjacent circuits was made into the evaluation result of initial stage connection resistance. Table 4 shows the evaluation results.

(Evaluation of circuit connection structure 2: evaluation of initial adhesive force)

For the circuit connection structures obtained in Examples and Comparative Examples, the adhesive force between the connecting member and the FPC board was measured by a 90 degree peeling method according to JIS-Z0237, respectively, and the measured value was used as the evaluation result of the initial adhesive force. In addition, the Toyo Baldwin Co., Ltd. product Tensilon UTM-4 (peel rate 50 mm/min, 25 degreeC) was used as the measuring apparatus of adhesive force. Table 4 shows the evaluation results.

(Evaluation of circuit connection structure 3: Characteristic evaluation after high-temperature, high-humidity test)

The circuit connection structure obtained by the Example and the comparative example was hold|maintained on 85 degreeC and 85 %RH conditions for 250 hours, and the measurement sample was obtained. About the obtained sample, the method similar to the said evaluation 1 and 2 evaluated connection resistance and adhesive force. Table 4 shows the evaluation results.

Further, the obtained sample was examined for the presence or absence of peeling at the interface between the connecting member and the FPC substrate and at the interface between the connecting member and the glass substrate using a microscope (trade name: ECLIPSE L200, manufactured by Nikon Corporation). A thing with no interfacial peeling was evaluated as "A", a thing with some interfacial peeling as "B", and a thing in which interfacial peeling had generate|occur|produced to such an extent that there existed a problem practically was evaluated as "C". Table 4 shows the evaluation results.

As is clear from the results shown in Table 4, the circuit connection structures obtained in Examples 6 to 10 exhibited a resistance value of 3 Ω or less in the initial stage and after the high-temperature, high-humidity test, and peeling bubbles were formed at the interface between the connection member and the circuit member. etc. did not occur.

On the other hand, the circuit-connected structure of Comparative Example 6 obtained by using the film adhesive of Comparative Example 1 not containing inorganic fine particles and Comparative Example obtained using the film adhesive of Comparative Example 2 in which the content of inorganic fine particles is less than 5% by mass In the circuit connection structure of 7, after a high temperature, high humidity test, connection resistance rose remarkably, adhesive force fell, and peeling was seen at the interface of a connection member and a circuit member. Moreover, the circuit connection structure of the comparative example 8 obtained using the film adhesive of the comparative example 3 in which content of (b-2) exceeds 15 mass %, and the film form of the comparative example 5 which do not contain a silane coupling agent In the circuit connection structure of Comparative Example 10 obtained using the adhesive, peeling occurred remarkably at the interface between the connection member and the circuit member after the high-temperature, high-humidity test. Further, in the circuit bonded structure of Comparative Example 9 obtained by using the film adhesive of Comparative Example 4 in which the content of the component (b-2) exceeds 15% by mass without containing inorganic fine particles, the connection resistance increases, The adhesive force fell, and peeling generate|occur|produced remarkably at the interface of a connection member and a circuit member.

(Examples 11 to 15 and Comparative Examples 11 to 15))

Each of the coating solutions used for the production of the film adhesives of Examples 1 to 5 and Comparative Examples 1 to 5 were coated for 10 m on a polyethylene terephthalate (PET) film having a thickness of 50 μm, followed by hot air drying at 70° C. for 10 minutes. was performed, a film adhesive having a thickness of 16 µm was formed on the PET film, and an adhesive film comprising a PET film and a film adhesive was obtained.

The obtained adhesive film was cut out to 2 mm in width, it wound up on the reel shape with an inner diameter of 66 mm, and the roll body of the adhesive film was obtained.

(Evaluation of the rolled body of the adhesive film)

A load of 75 g was fixed to the tip of the rolled body of the obtained adhesive film, and the load was left to hang for 6 hours in an atmosphere of 30°C. The roll body after leaving-to-stand was observed, and the presence or absence of the seepage of the film adhesive from between PET films was confirmed. Moreover, the adhesive film was taken out from the roll body after leaving-to-stand, and the presence or absence of transcription|transfer to the PET film back surface of the film adhesive was confirmed. The case where both exudation and transcription were not seen was evaluated as "A", the case where transcription was not seen but exudation was seen was evaluated as "B", and the case where both exudation and transcription were seen was evaluated as "C". Table 5 shows the evaluation results.

As is apparent from the results shown in Table 5, in the adhesive films obtained in Examples 11 to 15, seepage of the film adhesive was not seen even after leaving it to stand for 6 hours at 30°C under a load of 75 g, and the transfer to the back side of the PET film was not seen. didn't On the other hand, in Comparative Examples 11-13, the seepage of the film-form base material from between PET films was seen in the roll body. Moreover, in Comparative Examples 11 and 14, not only seepage but transfer of the film adhesive to the back surface of a PET film was seen.

1: Film adhesive
5: circuit connection material
7: conductive particles
10: connection member
11: insulating material
20: first circuit member
21: circuit board (first circuit board)
21a: Give
22: circuit electrode (first circuit electrode)
30: second circuit member
31: circuit board (second circuit board)
31a: give
32: circuit electrode (second circuit electrode)
40: film adhesive

Claims (1)

A circuit connection material for electrically connecting two circuit members opposing each other of a composition containing a thermoplastic resin, a radically polymerizable compound, a radical polymerization initiator, and inorganic fine particles, comprising:
The thermoplastic resin comprises at least one selected from a polyimide resin, a polyamide resin, a polyester resin, and a polyurethane resin,
The content of the radically polymerizable compound is 40% by mass or more based on the total amount of the composition,
The content of the compound having a molecular weight of 1000 or less in the radically polymerizable compound is 15% by mass or less based on the total amount of the composition,
The content of the inorganic fine particles is 5 to 30% by mass based on the total amount of the composition,
A circuit connection material, wherein the composition contains at least a compound represented by the following formula (1).
<Formula 1>

[Wherein, 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, R ¹ , R ^{At least one of 2} and R ³ is an alkoxy group having 1 to 5 carbon atoms, R ⁴ is a (meth)acryloyl group, a vinyl group, an isocyanate group, an imidazole group, a mercapto group, an amino group, a methylamino group, a dimethylamino group, a benzylamino group , a phenylamino group, a cyclohexylamino group, a morpholino group, a piperazino group, a ureido group or a glycidyl group, and n represents an integer of 1 to 10]

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