JP2013028675A - Circuit connection material, and circuit connection structure using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circuit connection material exhibiting high adhesive strength, and capable of sufficiently suppressing the generation of peeling bubbles at an interface between a circuit member and the circuit connection material in the case of a connected body is left in a high-temperature high humidity environment.SOLUTION: The circuit connection material contains (a) a thermoplastic resin, (b) a radical polymerizable compound, and (c) a radical polymerization initiator, wherein (b) the radical polymerizable compound is represented by formula (1), and satisfies the condition of the following expression (I): 10≤S2/S1≤14, wherein S1 is an integral value of a spectrum measured in the chemical shift value of 2.75 to 3.10 ppm inHNMR with tetramethylsilane as an internal standard; and S2 is an integral value thereof in 3.90 to 4.25 ppm. In the formula (1), Ris a hydrogen atom or a methyl group; j is an integer of 1 to 3; k is an integer of 2 to 7; m is an integer of 4 to 8; and n is an integer of 5 to 7.

Description

  The present invention relates to a circuit connection material for electrically connecting two opposing circuit members and a circuit connection structure using the same.

  In a semiconductor element and a liquid crystal display element, various circuit connection materials have been conventionally used for the purpose of bonding various members in the element. The characteristics required for circuit connection materials are diverse, including adhesiveness, heat resistance, reliability in high temperature and high humidity conditions, and the like.

In addition, the adherends used for bonding include organic substrates such as printed wiring boards, polyimide, polyethylene terephthalate and polycarbonate, metals such as copper and aluminum, ITO, IZO, SiN, SiO _{2 and the} like. Substrates having a wide variety of surface states are used. For this reason, the circuit connection material needs to have a molecular design tailored to each adherend (see, for example, Patent Documents 1 and 2).

  Conventionally, as a circuit connection material for a semiconductor element or a liquid crystal display element, a thermosetting resin using an epoxy resin having high adhesiveness and high reliability has been used (for example, see Patent Document 1). As a constituent component of the resin, a curing agent such as an epoxy resin, 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. The heat latent catalyst is an important factor for determining the curing temperature and the curing rate, and various compounds have been used from the viewpoint of storage stability at room temperature and curing rate during heating. The curing conditions in the actual process were that desired adhesion was obtained by curing at a temperature of 170 to 250 ° C. for 1 to 3 hours. However, with the recent high integration of semiconductor elements and high definition of liquid crystal elements, the pitch between elements and wirings has narrowed, and there has been a risk of adversely affecting peripheral members due to heating during curing. Furthermore, in order to reduce the cost, it is necessary to improve the throughput, and there is a demand for curing at a lower temperature and in a shorter time, in other words, adhesion at a lower temperature and faster curing. In order to achieve this low temperature rapid curing, it is necessary to use a thermal latent catalyst having a low activation energy, and it is known that it is very difficult to combine storage stability near room temperature.

  Recently, a radical curable adhesive using both an acrylate derivative or a methacrylate derivative (hereinafter referred to as “(meth) acrylate derivative”) and a peroxide as a radical polymerization initiator has attracted attention. Radical curing can be cured for a short time because radicals that are reactive species are rich in reactivity (see, for example, Patent Document 2). However, the radical curable adhesive has a problem that the adhesive strength is not always sufficient, and an example using urethane acrylate or urethane methacrylate (hereinafter referred to as “urethane (meth) acrylate”) has been reported to solve this problem. (For example, see Patent Documents 3 to 5). In particular, Patent Documents 4 and 5 have found a urethane (meth) acrylate structure that is particularly effective for properties such as adhesion.

Japanese Patent Laid-Open No. 1-113480 International Publication No. 98/44067 Pamphlet International Publication No. 2001/15505 Pamphlet JP 2006-257200 A JP 2006-257208 A

  However, a connection body (circuit connection structure) is produced using an adhesive composition containing urethane (meth) acrylate described in Patent Document 4 and Patent Document 5, and the connection body is, for example, 85 ° C. and 85% RH. The present inventors have found that exfoliated bubbles are generated at the interface between the circuit member and the circuit connecting material when left in a high temperature and high humidity environment.

  The present invention has been made in view of the above-described problems of the prior art, and exhibits high adhesive strength while being a radical curable adhesive, and when the connection body is left in a high temperature and high humidity environment, a circuit member and a circuit are provided. It is an object of the present invention to provide a circuit connection material that can sufficiently suppress the occurrence of peeling bubbles at the interface with the connection material, and a circuit connection structure using the circuit connection material.

［式（１）中、Ｒ^１は水素原子又はメチル基を示し、ｊは１〜３の整数を示し、ｋは２〜７の整数を示し、ｍは４〜８の整数を示し、ｎは５〜７の整数を示す。］ In order to achieve the above object, the present invention provides [1] a circuit connecting material for electrically connecting two circuit members facing each other, comprising (a) a thermoplastic resin and (b) a radically polymerizable material. A compound and (c) a radical polymerization initiator, wherein the (b) radical polymerizable compound is represented by the following general formula (1), and in ¹ HNMR using tetramethylsilane as an internal standard, the chemical shift value Where S1 is the integral value of the spectrum measured at 2.75 to 3.10 ppm, and S2 is the integral value of the spectrum measured at 3.90 to 4.25 ppm:
10 ≦ S2 / S1 ≦ 14 (I)
The circuit connection material containing the urethane (meth) acrylate which satisfy | fills these conditions is provided.

[In formula (1), R ¹ represents a hydrogen atom or a methyl group, j represents an integer of 1 to 3, k represents an integer of 2 to 7, m represents an integer of 4 to 8, and n represents An integer of 5 to 7 is shown. ]

  According to the circuit connecting material having such a configuration, the circuit member and the circuit are connected even when the connection body is left in a high-temperature and high-humidity environment even though it is a radical curable adhesive and has a high adhesive strength. It is possible to provide a circuit connection material that can sufficiently suppress the generation of peeling bubbles at the interface with the material.

［式（１）中、Ｒ^１は水素原子又はメチル基を示し、ｊは１〜３の整数を示し、ｋは２〜７の整数を示し、ｍは４〜８の整数を示し、ｎは５〜７の整数を示す。］ The present invention also provides [2] a circuit connecting material for electrically connecting two circuit members facing each other, wherein (a) a thermoplastic resin, (b) a radical polymerizable compound, and (c) Provided is a circuit connection material containing a radical polymerization initiator, wherein the (b) radical polymerizable compound contains urethane (meth) acrylate represented by the following general formula (1).

[In formula (1), R ¹ represents a hydrogen atom or a methyl group, j represents an integer of 1 to 3, k represents an integer of 2 to 7, m represents an integer of 4 to 8, and n represents An integer of 5 to 7 is shown. ]

  According to the circuit connecting material having such a configuration, the circuit member and the circuit are connected even when the connection body is left in a high-temperature and high-humidity environment even though it is a radical curable adhesive and has a high adhesive strength. It is possible to provide a circuit connection material that can sufficiently suppress the generation of peeling bubbles at the interface with the material.

  Moreover, this invention provides the circuit connection material as described in said [1] or [2] whose weight average molecular weights of [3] said urethane (meth) acrylate are 11000-25000.

  Moreover, this invention provides the circuit connection material in any one of said [1]-[3] which further contains [4] (d) electroconductive particle. (D) By further containing conductive particles, it is possible to impart conductivity or anisotropic conductivity to the circuit connection material, so that the circuit connection material is more suitable for connection applications between circuit members having circuit electrodes. Can be used. Moreover, the connection resistance between the circuit electrodes electrically connected via the circuit connection material can be sufficiently reduced.

  The present invention also provides [5] the circuit connection material according to any one of [1] to [4], wherein at least one of the two circuit members is a glass substrate or a plastic substrate.

  Furthermore, the present invention provides [6] the circuit connection material according to any one of [1] to [5], wherein at least one of the two circuit members is a flexible substrate.

  The present invention also provides [7] a pair of circuit members arranged opposite to each other and a circuit member provided between the pair of circuit members so that circuit electrodes of the pair of circuit members are electrically connected to each other. And a connection member for bonding the two, wherein the connection member is made of a cured product of the circuit connection material according to any one of [1] to [6].

  In such a circuit connection structure, since the connection member for connecting the pair of circuit members is composed of the cured product of the circuit connection material of the present invention, the circuit connection structure has a high adhesive strength and the circuit after being left in a high temperature and high humidity environment. It is possible to sufficiently suppress the occurrence of peeling bubbles at the interface between the member and the circuit connection material.

  According to the present invention, the interface between the circuit member and the circuit connecting material is a radical curable adhesive capable of reducing the temperature and time of the connection, exhibiting high adhesive strength, and after being left in a high temperature and high humidity environment. It is possible to provide a circuit connection material that can sufficiently suppress the occurrence of peeling bubbles in the substrate, and a circuit connection structure using the circuit connection material.

It is a schematic cross section which shows one Embodiment of the film adhesive which consists of a circuit connection material of this invention. It is a schematic cross section which shows one Embodiment of the connection structure of the circuit member of this invention. (A)-(c) is a series of process drawings which connect a circuit member, respectively.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as the case may be. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios. In the present invention, (meth) acrylic acid means acrylic acid or methacrylic acid corresponding thereto, (meth) acrylate means acrylate or methacrylate corresponding thereto, and (meth) acryloyl group means acryloyl group or The corresponding methacryloyl group is meant.

  The circuit connecting material of the present invention (hereinafter also simply referred to as “adhesive”) is a circuit connecting material for electrically connecting two circuit members facing each other, and includes (a) a thermoplastic resin (hereinafter referred to as “a thermoplastic resin”). Simply (also referred to as “component (a)”), (b) radical polymerizable compound (hereinafter also simply referred to as “(b) component”), and (c) radical polymerization initiator (hereinafter simply referred to as “(c) component”). "). Hereinafter, each component will be described.

  (A) As a thermoplastic resin, a well-known thermoplastic resin can be used without a restriction | limiting in particular. As known thermoplastic resins, polyimide resins, polyamide resins, phenoxy resins, poly (meth) acrylate resins, polyester resins, polyurethane resins, polyvinyl butyral resins, and the like can be used. Further, these thermoplastic resins may contain a siloxane bond or a fluorine substituent. These can be used individually by 1 type or in mixture of 2 or more types. When two or more kinds are mixed and used, the resins to be mixed can be suitably used as long as they are completely compatible with each other or microphase separation occurs and the liquid becomes cloudy.

  (A) Although the molecular weight of the thermoplastic resin is not particularly limited, the general weight average molecular weight is preferably from 5,000 to 200,000, particularly preferably from 10,000 to 150,000. If the weight average molecular weight is less than 5,000, the adhesive force tends to be reduced, and if it exceeds 200,000, the compatibility with other components tends to deteriorate, or the fluidity of the adhesive tends to decrease.

  The content of the (a) thermoplastic resin is preferably 20 to 80% by mass, more preferably 30 to 70% by mass, based on the total amount of the components (a) and (b), and 40 to 40%. It is especially preferable that it is 60 mass%. (A) If the content of the thermoplastic resin is less than 20% by mass, the adhesive strength tends to decrease or the film formability when used as a film tends to decrease. If the content exceeds 80% by mass, the fluidity of the adhesive Tends to decrease.

  Moreover, you may add a well-known rubber component to a circuit connection material for the purpose of stress relaxation and adhesive improvement as said (a) thermoplastic resin. Specific examples of rubber components include acrylic rubber, polyisoprene, polybutadiene, carboxyl group-terminated polybutadiene, hydroxyl-terminated polybutadiene, 1,2-polybutadiene, carboxyl group-terminated 1,2-polybutadiene, hydroxyl-terminated 1,2-polybutadiene, and styrene- Butadiene rubber, hydroxyl-terminated styrene-butadiene rubber, carboxyl group, hydroxyl group, carboxylated nitrile rubber, hydroxyl-terminated poly (oxypropylene), alkoxysilyl group-terminated poly (oxypropylene), poly (oxytetramethylene) glycol, polyolefin glycol, poly -Ε-caprolactone and the like.

  The rubber component is preferably a rubber component containing a cyano group or a carboxyl group, which is a highly polar group, in the side chain or terminal from the viewpoint of improving adhesiveness. These rubber components can be used individually by 1 type or in mixture of 2 or more types.

  (B) The radically polymerizable compound contains urethane (meth) acrylate that satisfies at least one of the following conditions (b1) and (b2).

(B1) Represented by the following general formula (1), in general formula (1), R ¹ represents a hydrogen atom or a methyl group, j represents an integer of 1 to 3, and k represents an integer of 2 to 7. , M represents an integer of 4 to 8, n represents an integer of 5 to 7, and in ¹ HNMR using tetramethylsilane as an internal standard, the chemical shift value is measured at 2.75 to 3.10 ppm. When the integral value is S1, and the integral value of the spectrum measured at 3.90 to 4.25 ppm is S2, the following formula (I):
10 ≦ S2 / S1 ≦ 14 (I)
Urethane (meth) acrylate that satisfies the following conditions.

(B2) Represented by the following general formula (1), in general formula (1), R ¹ represents a hydrogen atom or a methyl group, j represents an integer of 1 to 3, and k represents an integer of 3 to 5. , M represents an integer of 5 to 7, and n represents a urethane (meth) acrylate representing an integer of 5 to 7.

  The urethane (meth) acrylate represented by the general formula (1) has a structure derived from a polycarbonate polyol together with a (meth) acryloyl group in the molecule. In the urethane (meth) acrylate represented by the general formula (1), two (meth) acryloyl groups are present in the molecule from the viewpoint of imparting curability of the circuit connecting material.

  As a method for producing the urethane (meth) acrylate represented by the general formula (1), for example, a polyisocyanate (i) and a polyol (ii) containing a polycarbonate polyol, an isocyanate group having the polyisocyanate (i). The reaction is performed under the condition that the equivalent ratio of (NCO) to the hydroxyl group (OH) of the polyol (ii) is in the range of [NCO / OH] = 2 to 1.25, more preferably 1.6 to 1.25. Step (I) for producing a urethane resin (iii) having an isocyanate group at the molecular end thereof, the urethane resin (iii), one hydroxyl group and one (meth) acryloyl group (meth) Acrylic compound (iv) and (meth) acrylic compound (iv) have hydroxyl groups possessed by urethane resin (iii). And a method consisting of the step (II) is reacted under conditions substantially the equal amount with respect to cyanate groups.

  Here, as said polycarbonate polyol (ii), m in general formula (1) shows the integer of 4-8, and polycarbonate polyol which can obtain the urethane (meth) acrylate in which n shows the integer of 5-7 is obtained. From the viewpoint of the adhesive strength of the circuit connecting material, it is preferable to use 1,6-hexanediol-based polycarbonate. Polycarbonate polyol (ii) may be used individually by 1 type, and may use 2 or more types together.

  Moreover, as polyisocyanate (i) which can react with the said polycarbonate polyol (ii) etc., it is preferable to use isophorone diisocyanate which is isocyanate containing an aliphatic cyclic structure from a viewpoint of the adhesive force of a circuit connection material. Furthermore, 2,4-tolylene diisocyanate, its isomer or a mixture of these isomers, hexamethylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, dicyclohexylmethane diisocyanate, tolidine diisocyanate and the like are used in combination. can do.

  Examples of the (meth) acrylic compound (iv) containing one hydroxyl group and one (meth) acryloyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3 -Methacrylates having one hydroxyl group such as hydroxybutyl (meth) acrylate. Furthermore, mono (meth) acrylates of alcohol having two hydroxyl groups such as polyethylene glycol mono (meth) acrylate and polypropylene glycol mono (meth) acrylate can be used.

  The reaction step (I) is preferably performed in a range of room temperature to about 100 ° C., for example, in a nitrogen atmosphere. Moreover, this reaction process can also be performed under a non-solvent. Moreover, in the said reaction process (I), you may use a catalyst as needed.

  Examples of the catalyst include organic titanium compounds such as tetrabutyl titanate, tetrapropyl titanate, and tetraethyl titanate; organic tin compounds such as tin octylate, dibutyltin oxide, and sibutyltin dilaurate; and further, stannous chloride, bromide Known catalysts such as acids and alkalis such as stannous and stannous iodide can be used. The amount of these catalysts added is preferably 10 to 10,000 ppm with respect to the total charge.

  Moreover, it is preferable to perform the said reaction process (II) in the range of room temperature-about 90 degreeC. Moreover, the said reaction process (II) can also be performed under a non-solvent. Moreover, in the said reaction process (II), you may use the thing similar to the catalyst illustrated as what can be used by the said reaction process (I) as needed.

  Moreover, in order to suppress the radical polymerization of the polymerizable unsaturated double bond of the (meth) acrylic compound (iv), a radical polymerization inhibitor can be used as necessary. As the radical polymerization inhibitor, for example, toluhydroquinone, hydroquinone monomethyl ether, dt-butyl hydroquinone, pt-butyl catechol, phenothiazine and the like can be used. It is preferable that the usage-amount of the said radical polymerization inhibitor is 10-10,000 ppm with respect to the whole preparation amount.

  In the said General formula (1), j is an integer of 1-3, and it is preferable that it is 2 from the surface of the cost of material procurement.

  In the said General formula (1), k is an integer of 2-7, and it is preferable that it is an integer of 3-5. If k is less than 2, sufficient adhesive strength cannot be obtained, or peeling bubbles tend to occur at the interface between the circuit member and the circuit connecting material after leaving in a high temperature and high humidity environment. There is a tendency for the fluidity of the resin to decrease and the adhesive strength to decrease.

  In the said General formula (1), m is an integer of 4-8, and it is preferable that it is an integer of 5-7. When m is less than 4 or exceeds 8, the adhesive strength tends to decrease because the polarity of the adhesive is too high or too low.

  In the said General formula (1), n is an integer of 5-7, and it is especially preferable that it is 6. When n is less than 5 or exceeds 7, the adhesive strength tends to decrease because the polarity of the adhesive is too high or too low.

The urethane (meth) acrylate represented by the general formula (1) is an integral value of a spectrum measured at a chemical shift value of 2.75 to 3.10 ppm in ¹ HNMR using tetramethylsilane as an internal standard. Is S1, and the integrated value of the spectrum measured at 3.90 to 4.25 ppm is S2, the value of S2 / S1 is preferably 10 or more and 14 or less, and 11 or more and 13 or less. Particularly preferred. When S2 / S1 is less than 10 or exceeds 14, the adhesive strength tends to decrease because the polarity of the adhesive is too high or too low.

  The weight average molecular weight of the urethane (meth) acrylate represented by the general formula (1) is preferably 11000 to 25000, and particularly preferably 15000 to 20000. When the weight average molecular weight is less than 11,000, sufficient adhesive strength cannot be obtained, or peeling bubbles tend to occur at the interface between the circuit member and the circuit connecting material after leaving in a high temperature and high humidity environment. The fluidity of the agent tends to decrease and the adhesive strength tends to decrease.

  It is preferable that the compounding quantity of the urethane (meth) acrylate represented by the said General formula (1) is 5-70 mass% on the basis of the total amount of (a) component and (b) component, and 10-60 mass%. It is particularly preferred that When the blending amount is less than 5% by mass, the adhesive strength tends to decrease or the heat resistance tends to decrease. When the blending amount exceeds 70% by mass, air bubbles are peeled off at the interface between the circuit member and the circuit connecting material after being left in a high temperature and high humidity environment. Tends to occur.

  Moreover, in addition to the said urethane (meth) acrylate as a radically polymerizable compound (b) of this invention, a well-known radically polymerizable compound can be especially used without a restriction | limiting. In addition, the radical polymerizable compound can be used in either a monomer or oligomer state, and the monomer and oligomer may be mixed and used.

  Specific examples of the radical polymerizable compound include epoxy (meth) acrylate oligomers, urethane (meth) acrylate oligomers, polyether (meth) acrylate oligomers, polyester (meth) acrylate oligomers, and trimethylolpropane tri (meth) acrylate. , Polyethylene glycol di (meth) acrylate, polyalkylene glycol di (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, neopentyl glycol di (meth) acrylate, dipentaerythritol hexa (Meth) acrylate, isocyanuric acid modified bifunctional (meth) acrylate, isocyanuric acid modified trifunctional (meth) acrylate, bisphenol full orange Introduced (meth) acryloyloxy group into compounds in which ethylene glycol or propylene glycol was added to the glycidyl group of bisphenol fluorenediglycidyl ether, epoxy (meth) acrylate obtained by adding (meth) acrylic acid to the glycidyl group of ricidyl ether And polyfunctional (meth) acrylates such as the above compounds. These compounds can be used individually by 1 type or in mixture of 2 or more types.

  In addition to the above radical polymerizable compounds, pentaerythritol (meth) acrylate, 2-cyanoethyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (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) acrylate, n-lauryl (meth) acrylate, 2-methoxyethyl (meth) acrylate 2-phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2- (meth) acryloyloxyethyl phosphate, N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl ( You may use together (meth) acrylate, (meth) acryloyl morpholine, etc. These compounds can be used individually by 1 type or in mixture of 2 or more types.

  The circuit connecting material preferably contains at least one compound having two or more (meth) acryloyl groups in the molecule as the radical polymerizable compound.

  Furthermore, in addition to the compound having the (meth) acryloyl group, a compound having a functional group that polymerizes by an active radical such as an allyl group, a maleimide group, or a vinyl group is appropriately added to the circuit connection material as a radical polymerizable compound. May be. Specifically, N-vinylimidazole, N-vinylpyridine, N-vinylpyrrolidone, N-vinylformamide, N-vinylcaprolactam, 4,4′-vinylidenebis (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'-diphenylmethane Examples thereof include bismaleimide and 1,6-bismaleimide- (2,2,4-trimethyl) hexane.

  The blending amount of these (b) radical polymerizable compounds is preferably 20 to 80% by mass, more preferably 30 to 70% by mass based on the total amount of the component (a) and the component (b), It is especially preferable that it is 40-60 mass%. When the blending amount is less than 20% by mass, the heat resistance tends to be lowered. When the blending amount is more than 80% by mass, peeling bubbles tend to be generated at the interface between the circuit member and the circuit connecting material after being left in a high temperature and high humidity environment.

  Moreover, it is preferable to use together with the said radically polymerizable compound the radically polymerizable compound which has a phosphate ester structure represented by following General formula (2)-(4). In this case, since the adhesive strength to the surface of an inorganic material such as metal is improved, it is suitable for bonding circuit electrodes.

式（２）中、Ｒ^２は（メタ）アクリロイルオキシ基を示し、Ｒ^３は水素原子又はメチル基を示し、ｗ及びｘは各々独立に１〜８の整数を示す。なお、式中、Ｒ^２同士、Ｒ^３同士、ｗ同士及びｘ同士はそれぞれ同一でも異なっていてもよい。

In Formula (2), R ² represents a (meth) acryloyloxy group, R ³ 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 ^{2 s} , R ^{3 s} , w s, and x s may be the same or different.

式（３）中、Ｒ^４は（メタ）アクリロイルオキシ基を示し、ｙ及びｚは各々独立に１〜８の整数を示す。なお、式中、Ｒ^４同士、ｙ同士及びｚ同士はそれぞれ同一でも異なっていてもよい。

In formula (3), R ⁴ represents a (meth) acryloyloxy group, and y and z each independently represents an integer of 1 to 8. In the formula, R ^{4 s} , y s, and z s may be the same or different.

式（４）中、Ｒ^５は（メタ）アクリロイルオキシ基を示し、Ｒ^６は水素原子又はメチル基を示し、ａ及びｂは各々独立に１〜８の整数を示す。

In Formula (4), R ⁵ represents a (meth) acryloyloxy group, R ⁶ represents a hydrogen atom or a methyl group, and a and b each independently represent an integer of 1 to 8.

  In addition to the compounds represented by the general formulas (2) to (4), specific examples of the radical polymerizable compound having a phosphate ester structure include acid phosphooxyethyl methacrylate, acid phosphooxyethyl acrylate, and acid phosphooxy. Propyl methacrylate, acid phosphooxypolyoxyethylene glycol monomethacrylate, acid phosphooxypolyoxypropylene glycol monomethacrylate, 2,2'-di (meth) acryloyloxydiethyl phosphate, EO-modified phosphate dimethacrylate, phosphate-modified epoxy acrylate And vinyl phosphate.

  The radically polymerizable compound having a phosphate ester structure can be obtained, for example, by reacting phosphoric anhydride with 2-hydroxyethyl (meth) acrylate. Specific examples of the radical polymerizable compound having a phosphate ester structure include mono (2-methacryloyloxyethyl) acid phosphate, di (2-methacryloyloxyethyl) acid phosphate, and the like. These may be used alone or in combination of two or more compounds.

  The content of the radically polymerizable compound having a phosphate ester structure is preferably 0.01 to 10% by mass based on the total amount of the component (a) and the component (b), and 0.5 to 5% by mass. It is particularly preferred. If the content is less than 0.01% by mass, sufficient effects cannot be obtained, and if it is more than 10% by mass, migration tends to occur when used for connecting electronic materials.

  (C) The radical polymerization initiator is a curing agent that decomposes by heating to generate free radicals, and a known compound such as a conventionally known peroxide or azo compound can be used. However, from the viewpoints of stability, reactivity, and compatibility, a peroxide having a one-minute half-life temperature of 90 to 175 ° C. and a molecular weight of 180 to 1,000 is preferable. Here, “one-minute half-life temperature” refers to the temperature at which the half-life is 1 minute, and “half-life” refers to the time until the concentration of the compound decreases to half of the initial value.

  Specific examples of radical polymerization initiators include 1,1,3,3-tetramethylbutylperoxyneodecanoate, di (4-t-butylcyclohexyl) peroxydicarbonate, and di (2-ethylhexyl) peroxy. Dicarbonate, cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, dilauroyl peroxide, 1-cyclohexyl-1-methylethylperoxyneodecanoate, t -Hexylperoxyneodecanoate, t-butylperoxyneodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2, 5-Dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane, t-hexylpa Oxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyneoheptanoate, t-amylperoxy-2-ethylhexanoate, di-t-butyl Peroxyhexahydroterephthalate, t-amylperoxy-3,5,5-trimethylhexanoate, 3-hydroxy-1,1-dimethylbutylperoxyneodecanoate, 1,1,3,3-tetramethyl Butylperoxy-2-ethylhexanoate, t-amylperoxyneodecanoate, t-amylperoxy-2-ethylhexanoate, 3-methylbenzoyl peroxide, 4-methylbenzoyl peroxide, di ( 3-methylbenzoyl) peroxide, dibenzoyl peroxide, di (4-methylbenzene) Zoyl) peroxide, 2,2'-azobis-2,4-dimethylvaleronitrile, 1,1'-azobis (1-acetoxy-1-phenylethane), 2,2'-azobisisobutyronitrile, 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 monocarbo Nate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxybenzoate, dibutylperoxytrimethyladipate, t-amylperoxynormal octoate, t -Amyl peroxy isononanoate, t-amyl peroxybenzoate, etc. are mentioned. These compounds may be used alone or in combination of two or more compounds.

  Moreover, the compound which generate | occur | produces a radical by light irradiation with a wavelength of 150-750 nm can be used as a radical polymerization initiator. Such compounds include, for example, Photoinitiation, Photopolymerization, and Photocuring, J. Mol. -P. The α-acetaminophenone 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 alone or in combination with the above peroxides or azo compounds.

  Further, in order to suppress corrosion of the connection terminals of the circuit member, the amount of chlorine ions or organic acid contained in the radical polymerization initiator is preferably 5000 ppm or less, and further, less organic acid is generated after thermal decomposition. Those are more preferred. Further, since the stability of the produced circuit connecting material is improved, it is preferable to use a radical polymerization initiator having a mass retention of 20% by mass or more after being left open at room temperature and normal pressure for 24 hours.

  The content of the (c) radical polymerization initiator is preferably in the range of 0.1 to 30 parts by mass, and in the range of 1 to 20 parts by mass with respect to 100 parts by mass of the total amount of the components (a) and (b). It is more preferable that When the content of the radical polymerization initiator is less than 0.1 parts by mass, a sufficient reaction rate cannot be obtained and the adhesive strength tends to decrease. When the content is more than 30 parts by mass, the pot life tends to be shortened.

  The circuit connection material preferably further contains (d) conductive particles. Examples of the conductive particles (d) include metal particles such as Au, Ag, Pd, Ni, Cu, and solder, and carbon particles. Further, the conductive particles may be a non-conductive glass, ceramic, plastic or the like as a core, and the core is covered with the metal, metal particles, carbon or the like. When the conductive particles are made of plastic as a core and the core is coated with the above metal, metal particles, carbon, or the like, or heat-melted metal particles, the circuit members are deformable by heating and pressurization. Is preferable because the contact area between the conductive particles and the electrode increases and the connection reliability of the circuit is improved.

  When such conductive particles are contained, the circuit connection material can be suitably used as an anisotropic conductive circuit connection material.

  The content of the conductive particles is preferably 0.1 to 30% by volume, and more preferably 0.1 to 10% by volume based on the total volume of the solid content of the circuit connecting material. When this content is less than 0.1% by volume, the conductivity tends to be inferior, and when it exceeds 30% by volume, a short circuit between circuit electrodes tends to occur. In addition, content of electroconductive particle is determined based on the volume of each component of the circuit connection material before hardening at 23 degreeC. In addition, the volume of each component can be calculated | required by converting mass into a volume using specific gravity. Also, put an appropriate solvent (water, alcohol, etc.) that can wet the component well without dissolving or swelling the component whose volume is to be measured. It is also possible to obtain the volume increased by charging as the volume of the component.

  In addition, a stabilizer may be added to the circuit connecting material in order to control the curing rate and impart storage stability. Such stabilizers include quinone derivatives such as benzoquinone and hydroquinone, phenol derivatives such as 4-methoxyphenol and 4-t-butylcatechol, 2,2,6,6-tetramethylpiperidine-1-oxyl and 4 Aminoxyl derivatives such as -hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, and hindered amine derivatives such as tetramethylpiperidyl methacrylate are preferred.

  The addition amount of the stabilizer is preferably 0.01 to 15% by mass, more preferably 0.05 to 10% by mass, based on the total amount of the circuit connecting material. When this addition amount is less than 0.01% by mass, the effect of addition tends to be insufficient, and when it exceeds 15% by mass, the polymerization reaction tends to be inhibited.

  Adhesion aids such as coupling agents represented by alkoxysilane derivatives and silazane derivatives, adhesion improvers, and leveling agents may be appropriately added to the circuit connecting material. Specifically, a compound represented by the following general formula (5) is preferable as such an adhesion assistant. These adhesion assistants can be used alone or in combination of two or more.

式（５）中、Ｒ^７、Ｒ^８及びＲ^９は各々独立に、水素原子、炭素数１〜５のアルキル基、炭素数１〜５のアルコキシ基、炭素数１〜５のアルコキシカルボニル基、又は、アリール基を示し、Ｒ^１０は（メタ）アクリロイル基、ビニル基、イソシアナート基、イミダゾール基、メルカプト基、アミノ基、メチルアミノ基、ジメチルアミノ基、ベンジルアミノ基、フェニルアミノ基、シクロヘキシルアミノ基、モルホリノ基、ピペラジノ基、ウレイド基又はグリシジル基を示し、ｃは１〜１０の整数を示す。

In Formula (5), R ⁷ , R ⁸ and R ⁹ are each independently 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, and R ¹⁰ 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 group, a morpholino group, a piperazino group, a ureido group or a glycidyl group, and c represents an integer of 1 to 10.

  Furthermore, known organic and inorganic fine particles may be added to the circuit connecting material for the purpose of stress relaxation and heat resistance improvement. In this specification, organic and inorganic fine particles are excluded from the component (a).

  Specific examples of the organic fine particles include silicone fine particles, methacrylate-butadiene-styrene fine particles, acryl-silicone fine particles, polyamide fine particles, and polyimide fine particles. These may have a uniform structure or a core-shell structure.

  Specific examples of inorganic fine particles include fine metal oxide particles such as silica fine particles, alumina fine particles, silica-alumina fine particles, titania fine particles, zirconia fine particles, and zinc oxide fine particles.

  The circuit connection material of the present invention can be produced by mixing with or without using a solvent capable of dissolving and dispersing additive components such as a thermoplastic resin, polyurethane resin, radical polymerizable compound, radical polymerization initiator and stabilizer. . The conductive particles may be added as appropriate during the dissolution / dispersion process.

  The circuit connecting material can be used in the form of a film. Apply a solution such as a solvent added to the circuit connection material on a peelable substrate such as a fluororesin film, polyethylene terephthalate film, or release paper, or impregnate a substrate such as a non-woven fabric with the above solution for peeling. It can be used as a film by placing it on a conductive substrate and removing the solvent. Use in the form of a film is more convenient from the viewpoint of handleability.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of a film adhesive (film-like circuit connection material) made of the circuit connection material of the present invention. A film adhesive 1 shown in FIG. 1 is formed by forming the above-described circuit connecting material into a film. According to this film adhesive, it is easy to handle, can be easily installed on the adherend, and can be easily connected. Moreover, the film adhesive 1 may have a multilayer structure (not shown) which consists of 2 or more types of layers. Moreover, when the film adhesive 1 contains the said electroconductive particle (not shown), it can use suitably as an anisotropic conductive film.

  The circuit connection material and the film adhesive of the present invention can usually adhere adherends together 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 damage 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 circuit connection material and the film-like adhesive of the present invention, for example, adherends can be sufficiently bonded to each other even under short-time heating and pressurization for 15 seconds under conditions of 150 to 200 ° C. and 3 MPa. Is possible.

  Moreover, the circuit connection material and film adhesive of the present invention can be used as an adhesive for different types of adherends having different thermal expansion coefficients. Specifically, it is used as a semiconductor element adhesive material typified by anisotropic conductive adhesive, silver paste, silver film, etc., circuit connection material, CSP elastomer, CSP underfill material, LOC tape, etc. Can do.

  Hereinafter, the circuit connecting material and the film-like adhesive of the present invention are used as an anisotropic conductive circuit connecting material and an anisotropic conductive film, respectively, and circuit members having circuit electrodes formed on the main surface of the circuit board are used. An example of connection will be described. That is, an anisotropic conductive circuit connection material or an anisotropic conductive film is disposed between circuit electrodes facing each other on a circuit board, and is heated and pressed to make electrical connection between the circuit electrodes facing each other and between the circuit boards. The circuit members can be connected to each other. Here, as the circuit substrate for forming the circuit electrode, at least one is a substrate made of glass or polyethylene terephthalate or polycarbonate, and at least one is a flexible substrate made of an organic substance such as polyimide, polyethylene terephthalate or polycarbonate. The effect of the present invention is great. Furthermore, the circuit connection material of this invention can also use the board | substrate etc. which combined inorganic substance and organic substance, such as glass / epoxy. Moreover, when using the circuit connection material and film adhesive of this invention for the use as such a circuit connection material, it is preferable to make these contain electroconductive particle.

  FIG. 2 is a schematic cross-sectional view showing an embodiment of the circuit connection structure (circuit member connection structure) of the present invention. As shown in FIG. 2, the circuit member connection structure of the present embodiment includes a first circuit member 20 and a second circuit member 30 that are opposed to each other. A circuit connection member 10 is provided between the circuit member 30 and the circuit member 30.

  The first circuit member 20 includes a circuit board (first circuit board) 21 and a circuit electrode (first circuit electrode) 22 formed on the main surface 21 a of the circuit board 21. Note that an insulating layer (not shown) may be formed on the main surface 21a of the circuit board 21 in some cases.

  On the other hand, 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 31 a of the circuit board 31. In addition, an insulating layer (not shown) may be formed on the main surface 31a of the circuit board 31 according to circumstances.

The first and second circuit members 20 and 30 are not particularly limited as long as electrodes that require electrical connection are formed. Specifically, glass or plastic substrates, printed wiring boards, ceramic wiring boards, flexible wiring boards, semiconductor silicon chips, etc., on which electrodes are formed of ITO, IZO, etc., used for liquid crystal displays, are mentioned. Used in combination as needed. As described above, in the present embodiment, a material made of an organic material such as a printed wiring board or polyimide, a metal such as copper or aluminum, ITO (indium tin oxide), silicon nitride (SiN _x ), silicon dioxide (SiO ₂ ). Circuit members having various surface states such as inorganic materials such as the above can be used.

  The circuit connecting member 10 is made of a cured product of the circuit connecting material or film adhesive of the present invention. The circuit connecting member 10 may be composed of the insulating substance 11 alone or may contain the insulating substance 11 and the conductive particles 7 as shown in FIG. The conductive particles 7 are disposed not only between the circuit electrode 22 and the circuit electrode 32 facing each other but also between the main surfaces 21a and 31a. In the circuit member connection structure, the circuit electrodes 22 and 32 are electrically connected via the conductive particles 7. That is, the conductive particles 7 are in direct contact with both the circuit electrodes 22 and 32.

  Here, the electroconductive particle 7 is the electroconductive particle demonstrated previously, and the insulating substance 11 is the hardened | cured material of each insulating component which comprises the circuit connection material or film adhesive of this invention.

  In the circuit member connection structure, as described above, the circuit electrode 22 and the circuit electrode 32 facing each other are electrically connected via the conductive particles 7. For this reason, the connection resistance between the circuit electrodes 22 and 32 is sufficiently reduced. Therefore, the flow of current between the circuit electrodes 22 and 32 can be made smooth, and the functions of the circuit can be fully exhibited. When the circuit connecting member 10 does not contain the conductive particles 7, the circuit electrode 22 and the circuit electrode 32 are in direct contact with each other to be electrically connected.

  Since the circuit connection member 10 is composed of the circuit connection material of the present invention or a cured product of the film adhesive, the adhesion strength of the circuit connection member 10 to the circuit member 20 or 30 is sufficiently high, and a reliability test is performed. Stable performance (good adhesive strength and connection resistance) can be maintained even after (high temperature and high humidity test).

  Next, an example of a method for manufacturing the circuit member connection structure described above will be described with reference to FIG. First, the first circuit member 20 and the film-like circuit connecting material 40 described above are prepared (see FIG. 3A). The film-like circuit connection material 40 is formed by forming a circuit connection material (circuit connection material) into a film shape, and contains the conductive particles 7 and the adhesive component 5. Even when the circuit connecting material does not contain the conductive particles 7, the circuit connecting material can be used for anisotropic conductive bonding as an insulating adhesive, and is sometimes called NCP (Non-Conductive Paste). Further, when the circuit connecting material contains the conductive particles 7, the circuit connecting material may be referred to as ACP (Anisotropic Conductive Paste).

  The thickness of the film-like circuit connecting material 40 is preferably 6 to 50 μm. If the thickness of the film-like circuit connecting material 40 is less than 6 μm, the circuit connecting material tends to be insufficiently filled between the circuit electrodes 22 and 32. On the other hand, when the thickness exceeds 50 μm, the circuit connection material between the circuit electrodes 22 and 32 cannot be sufficiently removed, and it is difficult to ensure conduction between the circuit electrodes 22 and 32.

  Next, the film-like circuit connecting material 40 is placed on the surface of the first circuit member 20 on which the circuit electrodes 22 are formed. When the film-like circuit connecting material 40 is attached on a support (not shown), the film-like circuit connecting material 40 side is directed to the first circuit member 20 so that the first circuit is connected. Place on member 20. At this time, the film-like circuit connecting material 40 is film-like and easy to handle. For this reason, the film-like circuit connecting material 40 can be easily interposed between the first circuit member 20 and the second circuit member 30, and the first circuit member 20 and the second circuit member 30 Connection work can be performed easily.

  And the film-form circuit connection material 40 is pressurized to the arrow A and B direction of Fig.3 (a), and the film-form circuit connection material 40 is temporarily connected to the 1st circuit member 20 (refer FIG.3 (b)). . At this time, you may pressurize, heating. However, the heating temperature is lower than the temperature at which the circuit connecting material in the film-like circuit connecting material 40 is not cured.

  Subsequently, as shown in FIG. 3C, the second circuit member 30 is placed on the film-like circuit connection material 40 so that the second circuit electrode faces the first circuit member 20. In addition, when the film-form circuit connection material 40 has adhered on the support body (not shown), after peeling a support body, the 2nd circuit member 30 is mounted on the film-form circuit connection material 40. FIG. At this time, the second circuit member can be temporarily fixed by positioning so that the first and second circuit electrodes face each other and then heating and pressurizing from above the second circuit member. By doing so, it is possible to suppress the positional deviation of the electrodes during the subsequent main connection. The heating temperature at the time of temporary fixing is set to a temperature lower than the temperature at which the circuit connecting material in the film-like circuit connecting material 40 is not cured, and the time from the alignment to the completion of temporary fixing is preferably 5 seconds or less for shortening the throughput. .

  And it heats through the 1st and 2nd circuit members 20 and 30 to the arrow A and B direction of FIG.3 (c), heating the film-form circuit connection material 40. FIG. The heating temperature at this time is set to a temperature at which the polymerization reaction can be started. In this way, the film-like circuit connecting material 40 is cured to perform the main connection, and a circuit member 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 to 120 seconds. These conditions are appropriately selected depending on the intended use, circuit connection material, and circuit member, and may be post-cured as necessary.

  By manufacturing the circuit member connection structure as described above, in the circuit member connection structure obtained, the conductive particles 7 can be brought into contact with both of the circuit electrodes 22 and 32 facing each other. , 32 can be sufficiently reduced.

  Further, by heating the film-like circuit connecting material 40, the adhesive component 5 is cured to become the insulating substance 11 in a state where the distance between the circuit electrode 22 and the circuit electrode 32 is sufficiently small, and the first circuit member is obtained. 20 and the second circuit member 30 are firmly connected via the circuit connection member 10. That is, in the circuit member connection structure obtained, since the circuit connection member 10 is made of a cured product of the circuit connection material made of the circuit connection material of the present invention, the circuit connection member 10 is connected to the circuit member 20 or 30. Adhesive strength can be sufficiently increased, and connection resistance between electrically connected circuit electrodes can be sufficiently reduced. Moreover, even when kept in a high temperature and high humidity environment for a long time, it can sufficiently suppress the decrease in adhesive strength and increase in connection resistance, and peels off at the interface between the circuit member and the circuit connection material. It is possible to sufficiently suppress the generation of bubbles.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

(Synthesis of urethane acrylate resin)
<Synthesis Example 1: Synthesis of urethane acrylate resin (UA-1) having acryloyl group and polycarbonate skeleton>
A 2-liter four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet, and a reflux condenser was charged with 531 parts by mass of methyl ethyl ketone, and polycarbonate diol (manufactured by Ube Industries, Ltd., trade name: ETERNACOLL UH-) 100, number average molecular weight: 1000) was added by 900 parts by mass, then isophorone diisocyanate (hereinafter abbreviated as “IPDI”) was added by 266 parts by mass, and the reaction was carried out at 70 ° C. for 3 hours while suppressing heat generation. After confirming that the NCO equivalent became 1944 which is almost the same as the theoretical value with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction solution was cooled to 40 ° C., and a polymerization inhibitor was obtained. And 0.062 parts by mass of toluhydroquinone, 73 parts by mass of 2-hydroxyethyl acrylate, and 0.062 parts by mass of a tin-based catalyst as a reaction promoting catalyst were added and reacted at 70 ° C. for 5 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less using an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated, and urethane acrylate resin (UA-1 )

<Synthesis Example 2: Synthesis of urethane acrylate resin (UA-2) having acryloyl group and polycarbonate skeleton>
Into the same reactor as in Synthesis Example 1, 499 parts by weight of methyl ethyl ketone was charged, and 800 parts by weight of polycarbonate diol (manufactured by Ube Industries, trade name: ETERRNACOLL UH-100, number average molecular weight: 1000) was added thereto, 266 parts by mass of IPDI was added and reacted at 70 ° C. for 3 hours while suppressing heat generation. After confirming that the NCO equivalent was 1333 which was almost the same as the theoretical value with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction solution was cooled to 40 ° C. and a polymerization inhibitor. And 0.058 parts by mass of tolhydroquinone, 97 parts by mass of 2-hydroxyethyl acrylate, and 0.058 parts by mass of a tin-based catalyst as a reaction promoting catalyst were added and reacted at 70 ° C. for 5 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less using an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated, and urethane acrylate resin (UA-2 )

<Synthesis Example 3: Synthesis of urethane acrylate resin (UA-3) having acryloyl group and polycarbonate skeleton>
Into the same reactor as in Synthesis Example 1, 564 parts by mass of methyl ethyl ketone was charged, and polycarbonate diol (manufactured by Ube Industries, trade name: ETERRNACOLL UH-100, number average molecular weight: 1000) was added thereto in an amount of 1000 parts by mass. 266 parts by mass of IPDI was added and reacted at 70 ° C. for 3 hours while suppressing heat generation. After confirming that the NCO equivalent was 3166 which was almost the same as the theoretical value with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction liquid was cooled to 40 ° C., and a polymerization inhibitor was obtained. And 0.066 parts by mass of tolhydroquinone, 49 parts by mass of 2-hydroxyethyl acrylate, and 0.066 parts by mass of a tin-based catalyst as a reaction promoting catalyst were added and reacted at 70 ° C. for 5 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less using an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated, and urethane acrylate resin (UA-3 )

<Comparative Synthesis Example 1: Synthesis of urethane acrylate resin (UA-4) having acryloyl group and polycarbonate skeleton>
In the same reactor as in Synthesis Example 1, 526 parts by mass of methyl ethyl ketone was charged, and polycarbonate diol (manufactured by Ube Industries, trade name: ETERRNACOLL UH-200, number average molecular weight: 2000) was added thereto in an amount of 1000 parts by mass. 167 parts by mass of IPDI was added and reacted at 70 ° C. for 4 hours while suppressing heat generation. After confirming that the NCO equivalent was 2333 which was almost the same as the theoretical value with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction solution was cooled to 40 ° C. and a polymerization inhibitor. 0.061 parts by mass of toluhydroquinone, 61 parts by mass of 2-hydroxyethyl acrylate, and 0.061 parts by mass of a tin-based catalyst as a reaction promoting catalyst were added and reacted at 70 ° C. for 6 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less using an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated, and urethane acrylate resin (UA-4 )

<Comparative Synthesis Example 2: Synthesis of urethane acrylate resin (UA-5) having acryloyl group and polycarbonate skeleton>
Into the same reactor as in Synthesis Example 1, 491 parts by mass of methyl ethyl ketone was charged, and polycarbonate diol (manufactured by Ube Industries, trade name: ETERRNACOLL UH-200, number average molecular weight: 2000) was added thereto in an amount of 600 parts by mass. 400 parts by mass of IPDI was added and reacted at 70 ° C. for 3 hours while suppressing heat generation. After confirming that the NCO equivalent was almost equal to the theoretical value of 833 with a potentiometric automatic titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction liquid was cooled to 40 ° C., and a polymerization inhibitor was obtained. And 0.057 parts by mass of tolhydroquinone, 146 parts by mass of 2-hydroxyethyl acrylate, and 0.057 parts by mass of a tin-based catalyst as a reaction promoting catalyst were added and reacted at 70 ° C. for 5 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated, and urethane acrylate resin (UA-5 )

<Comparative Synthesis Example 3: Synthesis of urethane acrylate resin (UA-6) having an acryloyl group but not a polycarbonate skeleton>
563 parts by mass of methyl ethyl ketone was charged into the same reactor as in Synthesis Example 1, 842 parts by mass of a polyester polyol (number average molecular weight: 560) composed of isophthalic acid and polyethylene glycol was added thereto, and then 400 parts by mass of IPDI. In addition, the reaction was carried out at 70 ° C. for 3 hours while suppressing exotherm. After confirming that the NCO equivalent was almost the same as the theoretical value 2068 with a potentiometric automatic titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction liquid was cooled to 40 ° C., and a polymerization inhibitor was obtained. And 0.066 parts by mass of tolhydroquinone, 73 parts by mass of 2-hydroxyethyl acrylate, and 0.066 parts by mass of a tin-based catalyst as a reaction promoting catalyst were added and reacted at 70 ° C. for 5 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less using an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated, and urethane acrylate resin (UA-6 )

<Comparative Synthesis Example 4: Synthesis of urethane acrylate resin (UA-7) having an acryloyl group but no polycarbonate skeleton>
Into the same reactor as in Synthesis Example 1, 539 parts by mass of methyl ethyl ketone was charged, 918 parts by mass of polypropylene glycol (number average molecular weight: 1000) was added thereto, and then 266 parts by mass of IPDI was added to suppress the generation of heat. The reaction was carried out at 3 ° C for 3 hours. After confirming that the NCO equivalent was 1974 which was almost the same as the theoretical value with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction liquid was cooled to 40 ° C., and a polymerization inhibitor was obtained. And 0.063 parts by mass of tolhydroquinone, 73 parts by mass of 2-hydroxyethyl acrylate, 0.063 parts by mass of a tin-based catalyst as a reaction promoting catalyst, and reacted at 70 ° C. for 5 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated, and urethane acrylate resin (UA-7 )

<Comparative Synthesis Example 5: Synthesis of urethane acrylate resin (UA-8) having acryloyl group and polycarbonate skeleton>
506 parts by mass of methyl ethyl ketone was charged into the same reactor as in Synthesis Example 1, and 700 parts by mass of polycarbonate diol (Ube Industries, trade name: ETERRNACOLL UH-100, number average molecular weight: 1000) was added thereto, 311 parts by mass of IPDI was added and reacted at 70 ° C. for 3 hours while suppressing heat generation. After confirming that the NCO equivalent was almost the same as the theoretical value 505 and stabilized with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction solution was cooled to 40 ° C. And 0.059 parts by mass of tolhydroquinone, 171 parts by mass of 2-hydroxyethyl acrylate, 0.059 parts by mass of a tin-based catalyst as a reaction promoting catalyst, and reacted at 70 ° C. for 5 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less using an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated, and urethane acrylate resin (UA-8 )

<Comparative Synthesis Example 6: Synthesis of urethane acrylate resin (UA-9) having acryloyl group and polycarbonate skeleton>
Into the same reactor as in Synthesis Example 1, 521 parts by mass of methyl ethyl ketone was charged, and 1040 parts by mass of polycarbonate diol (Ube Industries, trade name: ETERRNACOLL UH-200, number average molecular weight: 2000) was added thereto, 144 parts by mass of IPDI was added and reacted at 70 ° C. for 4 hours while suppressing heat generation. After confirming that the NCO equivalent was 4676 which was almost the same as the theoretical value with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction solution was cooled to 40 ° C., and a polymerization inhibitor was obtained. And 0.061 parts by mass of toluhydroquinone, 32 parts by mass of 2-hydroxyethyl acrylate, 0.061 parts by mass of a tin-based catalyst as a reaction promoting catalyst, and reacted at 70 ° C. for 5 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less with an automatic potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated, and urethane acrylate resin (UA-9 )

<Comparative Synthesis Example 7: Synthesis of urethane acrylate resin (UA-10) having acryloyl group and polycarbonate skeleton>
In the same reactor as in Synthesis Example 1, 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 a tin-based catalyst 4.9 parts by mass was charged and heated to 70 ° C., and 666 parts by mass of IPDI was uniformly dropped over 3 hours to be reacted. After completion of dropping, the reaction was continued for 15 hours, and when the NCO content was confirmed to be 0.2% by mass or less using a potentiometric automatic titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was performed. And urethane acrylate resin (UA-10) was obtained. This urethane acrylate resin UA-10 corresponds to the urethane acrylate described in Example 3 of JP-A-2006-257208.

<Comparative Synthesis Example 8: Synthesis of urethane acrylate resin (UA-11) having acryloyl group and polycarbonate skeleton>
Charge 614 parts by mass of methyl ethyl ketone, 1120 parts by mass of polycarbonate diol (ETERNACOLL UH-100 manufactured by Ube Industries, average molecular weight 1000) in the same reactor as in Synthesis Example 1, and then add 279 parts by mass of IPDI. While maintaining at 70 ° C. for 3 hours. After confirming that the NCO equivalent was 4999 which was almost the same as the theoretical value with a potentiometric titrator (trade name: AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction liquid was cooled to 40 ° C. and used as a polymerization inhibitor. 0.072 parts by mass of tolhydroquinone, 34 parts by mass of 2-hydroxyethyl acrylate, and 0.070 parts by mass of a tin-based catalyst as a reaction promoting catalyst were added and reacted at 70 ° C. for 5 hours in an air atmosphere. When it was confirmed that the NCO content was 0.2% by mass or less with a potentiometric titrator (AT-510, manufactured by Kyoto Electronics Co., Ltd.), the reaction was terminated to obtain a urethane acrylate resin (UA-11).

(Measurement of ¹ HNMR of urethane acrylate resin)
The urethane acrylate resin samples synthesized in the synthesis examples and comparative synthesis examples were dissolved in deuterated chloroform (containing tetramethylsilane), and the chemical shift value was measured using an NMR apparatus (trade name: AV-300) manufactured by Bruker BioSpin. The integral value (S1) of the spectrum measured at 2.75 to 3.10 ppm and the integral value (S2) of the spectrum measured at the chemical shift value of 3.90 to 4.25 ppm were measured.

(Measurement of molecular weight of urethane acrylate resin)
The weight average molecular weights of the urethane acrylate resins synthesized in the synthesis examples and comparative synthesis examples were measured using a standard polystyrene calibration curve by gel permeation chromatography (GPC) under the conditions shown in Table 1 below.

  About the urethane acrylate resin synthesized in the synthesis examples and comparative synthesis examples, the weight average molecular weight (Mw) and those having the structure represented by the general formula (1) (UA-1 to 5 and 8 to 10) The values of j, k, m and n and the value of S2 / S1 in the formula are shown in Table 2 below.

(Preparation of conductive particles)
A layer made of nickel was provided on the surface of the polystyrene particles so as to have a thickness of 0.2 μm, and a layer made of gold was provided on the surface of the layer made of nickel so as to have a thickness of 0.04 μm. . Thus, conductive particles having an average particle diameter of 5 μm were produced.

(Examples 1-7, Comparative Examples 1-8)
(A) Phenoxy resin and urethane resin were used as the thermoplastic resin. 40 g of phenoxy resin (trade name: PKHC, weight average molecular weight: 45000, manufactured by Union Carbide) was dissolved in 60 g of methyl ethyl ketone to obtain a solution having a solid content of 40% by mass. The urethane resin is composed of 450 parts by weight of polybutylene adipate diol having a weight average molecular weight of 2000, 450 parts by weight of polyoxytetramethylene glycol having a weight average molecular weight of 2000, and 100 parts by weight of 1,4-butylene glycol. A urethane resin having a weight average molecular weight of 150,000 obtained by adding 390 parts by mass of diphenylmethane diisocyanate and reacting at 70 ° C. was added. (B) As radically polymerizable compounds, the urethane acrylates UA-1 to UA-10, cyclohexyl acrylate (manufactured by Toagosei Co., Ltd., trade name: CHA), and 2- (meth) acryloyloxyethyl phosphate ( Kyoeisha Chemical Co., Ltd., trade name: Light Ester P-2M) was used. (C) As a radical polymerization initiator, t-hexyl peroxy-2-ethylhexanoate (manufactured by NOF Corporation, trade name: perhexyl O) was used. The above components are blended in a solid mass ratio as shown in Table 3 below, and the conductive particles are further mixed and dispersed by 1.5% by volume on the basis of the total volume of the solid content of the circuit connection material. Prepared. This circuit connecting material is applied to a polyethylene terephthalate (PET) film having a thickness of 50 μm using a coating apparatus, and dried with hot air at 70 ° C. for 10 minutes, whereby a film-like circuit connecting material having a thickness of 15 μm is formed on the PET film. Was made.

(Production of circuit connection structure)
The film-like circuit connecting material is formed on a glass (thickness 1.1 mm, surface resistance 20Ω / □) on which a thin layer of indium oxide (ITO) having a thickness of 0.2 μm is formed in 1 MPa at a temperature of 70 ° C. for 2 seconds. Transcribed. Next, this ITO substrate and a flexible circuit board (FPC) having 500 copper circuits having a line width of 25 μm, a pitch of 50 μm and a thickness of 18 μm are combined with a thermocompression bonding apparatus (heating method: constant heat type, manufactured by Toray Engineering Co., Ltd.). ) At 160 ° C. and 3 MPa for 10 seconds. Thereby, the connection body (circuit connection structure) which connected the FPC board and the ITO board | substrate with the hardened | cured material of the film-form circuit connection material over width 2mm was produced.

(Measurement of connection resistance and adhesive strength)
The resistance value (connection resistance) between adjacent circuits of the obtained connection body was measured with a multimeter. The resistance value was shown as an average of 37 resistances between adjacent circuits. Moreover, the adhesive strength of the connection body was measured and evaluated by a 90-degree peeling method in accordance with JIS-Z0237. Here, Tensilon UTM-4 (peeling speed 50 mm / min, 25 ° C.) manufactured by Toyo Baldwin Co., Ltd. was used as an adhesive force measuring apparatus. The connection resistance and adhesive force were measured immediately after connection (initial stage) and after being held in a high-temperature and high-humidity tank at 85 ° C. and 85% RH for 250 hours. The results are shown in Table 4.

(Observation of connection appearance)
After holding the connected body in a high-temperature and high-humidity tank at 85 ° C. and 85% RH for 250 hours, using a microscope (made by Nikon Corporation, trade name: ECLIPSE L200), a cured product of the film-like circuit connecting material and FPC And the presence or absence of peeling at the interface with the glass was examined. When there is no interfacial debonding in both FPC and glass, “◯”, when there is slight interfacial debonding in at least one of FPC and glass (to the extent that there is no practical problem), “△”, at least one interface between FPC and glass The case where there was peeling (there was a problem in practice) was evaluated as “x”. The evaluation results are shown in Table 4.

  As is apparent from the results shown in Table 4, the film-like circuit connecting materials obtained in Examples 1 to 5 were 4Ω or less both at the initial stage and after being held at 85 ° C. and 85% RH for 250 hours. Good connection resistance and good adhesive strength of 700 N / m or more were obtained. On the other hand, the film-like circuit connecting material of Comparative Example 1 using a urethane acrylate resin having a S2 / S1 value greater than 14 and the film shape of Comparative Example 2 using a urethane acrylate resin having a S2 / S1 value of less than 10 It was confirmed that the adhesive strength of the circuit connecting material was lowered. Moreover, it was confirmed that the adhesive force of the film-like circuit connecting materials of Comparative Examples 3 and 4 using a urethane acrylate resin having a structure different from that of the general formula (1) is low. Further, in Comparative Example 5 in which k in the general formula (1) is less than 2 and the weight average molecular weight is less than 13000, the adhesive strength is lowered, and interfacial peeling occurs after holding at 85 ° C. and 85% RH for 250 hours. It was confirmed that it occurred. Further, in Comparative Example 6 and Comparative Example 8 in which m in the general formula (1) is larger than 8, the value of S2 / S1 is larger than 14, and the weight average molecular weight is larger than 25000, the adhesive force is lowered and 85 ° C. It was confirmed that the connection resistance significantly increased after holding at 85% RH for 250 hours. Furthermore, the film-like circuit connection material of Comparative Example 7 using urethane acrylate produced by the same method as in Example 3 of JP-A-2006-257208, which is a known example, showed good connection resistance and adhesive strength. However, it was confirmed that interfacial peeling occurred after holding at 85 ° C. and 85% RH for 250 hours.

DESCRIPTION OF SYMBOLS 1 ... Film adhesive, 2 ... Semiconductor device, 5 ... Adhesive component, 7 ... Conductive particle, 10 ... Circuit connection member, 11 ... Insulating substance, 20 ... First circuit member, 21 ... Circuit board (first One circuit board), 21a ... main surface, 22 ... circuit electrode (first circuit electrode), 30 ... second circuit member, 31 ... circuit board (second circuit board), 31a ... main surface, 32 ... Circuit electrode (second circuit electrode), 40: film-like circuit connecting material.

Claims (7)

A circuit connecting material for electrically connecting two circuit members facing each other,
(A) a thermoplastic resin, (b) a radical polymerizable compound, and (c) a radical polymerization initiator,
The (b) radical polymerizable compound is represented by the following general formula (1), and in ¹ HNMR using tetramethylsilane as an internal standard, the integral of a spectrum measured at a chemical shift value of 2.75 to 3.10 ppm. When the value is S1, and the integral value of the spectrum measured at 3.90 to 4.25 ppm is S2, the following formula (I):
10 ≦ S2 / S1 ≦ 14 (I)
Circuit connection material containing urethane (meth) acrylate that satisfies the following conditions.

[In formula (1), R ¹ represents a hydrogen atom or a methyl group, j represents an integer of 1 to 3, k represents an integer of 2 to 7, m represents an integer of 4 to 8, and n represents An integer of 5 to 7 is shown. ] A circuit connecting material for electrically connecting two circuit members facing each other,
(A) a thermoplastic resin, (b) a radical polymerizable compound, and (c) a radical polymerization initiator,
The said (b) radically polymerizable compound is a circuit connection material containing the urethane (meth) acrylate represented by following General formula (1).

[In formula (1), R ¹ represents a hydrogen atom or a methyl group, j represents an integer of 1 to 3, k represents an integer of 2 to 7, m represents an integer of 4 to 8, and n represents An integer of 5 to 7 is shown. ]   The circuit connection material of Claim 1 or 2 whose weight average molecular weights of the said urethane (meth) acrylate are 11000-25000.   (D) The circuit connection material according to any one of claims 1 to 3, further comprising conductive particles.   The circuit connection material according to any one of claims 1 to 4, wherein at least one of the two circuit members is a glass substrate or a plastic substrate.   The circuit connection material according to claim 1, wherein at least one of the two circuit members is a flexible substrate. A pair of circuit members disposed opposite to each other;
A connecting member that is provided between the pair of circuit members, and that bonds the circuit members such that the circuit electrodes of the pair of circuit members are electrically connected;
With
The circuit connection structure which the said connection member consists of the hardened | cured material of the circuit connection material as described in any one of Claims 1-6.

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