JP6065407B2 - Circuit connection material, film-like circuit connection material, circuit connection sheet, circuit connection body and circuit member connection method - Google Patents

Description

  The present invention relates to a circuit connection material, a film-like circuit connection material, a circuit connection sheet, a circuit connection body, and a circuit member connection method.

  In the manufacture of semiconductor elements and liquid crystal display elements, various adhesives have been conventionally used for the purpose of bonding various circuit members in the elements. For example, a connection between a liquid crystal display element and TCP (Tape Carrier Package) or COF (Chip On Film), a connection between TCP or COF and a printed wiring board, a connection between an FPC (Flexible Printed Circuit) and a printed wiring board, or An adhesive is used for mounting a semiconductor element on a substrate.

Examples of the adherend include printed wiring boards, polyimides, organic base materials such as polyethylene terephthalate (PET), polycarbonate (PC) and polyethylene naphthalate (PEN), metals such as copper and aluminum, ITO (Indium Tin Oxide: indium and Base materials having various surface states such as composite oxide of tin, Si ₃ N ₄ , and SiO ₂ are used. Therefore, regarding the adhesive, a molecular design tailored to each adherend is required. The properties required for such adhesives are diverse, including adhesiveness and circuit connectivity, heat resistance, reliability in high temperature and high humidity conditions, and the like.

  Conventionally, as an adhesive for a semiconductor element or a liquid crystal display element, a thermosetting resin including an epoxy resin exhibiting high adhesiveness and high reliability has been used (for example, see Patent Document 1). As a component of the thermosetting 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. A thermal latent catalyst is a substance that does not react at a storage temperature such as room temperature and exhibits high reactivity when heated. Thermal latent catalyst is an important factor in determining the curing temperature and curing rate. Various compounds are selected as thermal latent catalysts from the viewpoints of storage stability of the adhesive at room temperature and curing rate during heating. In the actual process, the desired adhesiveness is generally obtained by the curing conditions of heating at a temperature of 170 ° C. to 250 ° C. for 1 to 3 hours.

  On the other hand, with recent high integration of semiconductor elements and high definition of liquid crystal display, the pitch between elements and wirings is narrowed, and the heat during curing tends to adversely affect peripheral members. Is required to be cured. Moreover, since it is necessary to improve the throughput for cost reduction, it is also required to cure the adhesive in a short time.

  In order to achieve low-temperature and short-time curing (low-temperature rapid curability) with a conventional thermosetting resin including an epoxy resin, it is necessary to use a thermal latent catalyst having a low activation energy. However, in that case, there is a problem that the storage stability of the adhesive at room temperature is lowered.

  Instead, as an adhesive having a low temperature fast curing property, a radical curable adhesive using a radical polymerizable compound such as a (meth) acrylate derivative and a peroxide which is a radical polymerization initiator has attracted attention (for example, , See Patent Document 2). According to radical curing, radicals that are reactive species are rich in reactivity, so that curing at a low temperature and in a short time is possible.

  However, in the case of an adhesive using radical curing, since the curing shrinkage at the time of curing is large, the adhesive strength is inferior to that of an adhesive using an epoxy resin, and in particular, the adhesive strength to a base material made of an inorganic material or a metal material. There is a tendency to decrease.

  Further, a semiconductor element or a liquid crystal display element using a glass substrate or the like, or a printed circuit board using an FR4 base material or the like and a flexible wiring board (FPC) having a polymer film such as polyimide or polyester as a base material are connected. In this case, the internal stress based on the difference in thermal expansion coefficient is increased, and there is a possibility that the adhesive is peeled off and the connection reliability is lowered.

  As a method for improving the adhesive strength, a method using an adhesion assistant typified by a silane coupling agent (for example, see Patent Document 3), a method for improving the adhesive strength by imparting flexibility to a cured product by an ether bond. (For example, refer patent document 4), the method (refer patent document 5, 6 etc.) etc. which improve the adhesive strength by disperse | distributing the stress-absorbing particle which consists of rubber-type elastic materials in an adhesive agent are proposed.

  In addition, as an adhesive capable of adhering organic base materials such as polyimide, polyethylene terephthalate, polycarbonate, and polyethylene naphthalate, a compound having an ethylenically unsaturated group and an isocyanate group, and a compound having a maleimide group and an ethylenically unsaturated group There has been proposed a photopolymerization-curable composition containing: (see Patent Document 7).

  In addition, it has been proposed to use a resin paste composition containing a monofunctional imide acrylate, a radical initiator, and a filler in order to bond a semiconductor element to a support member such as a lead frame (see Patent Document 8). According to Patent Document 8, by using such a resin paste composition, it is said that a semiconductor device free from reflow cracks can be provided even when a copper frame and an organic substrate are used.

Japanese Patent Laid-Open No. 1-113480 International Publication No. 98/044067 Japanese Patent No. 3344886 Japanese Patent No. 3503740 Japanese Patent No. 3477367 International Publication No. 09/020005 JP 2011-38088 A JP 2000-239616 A

  When connecting a circuit member having a base material containing a thermoplastic resin having low heat resistance such as polyethylene terephthalate (PET), polycarbonate (PC), polyethylene naphthalate (PEN), etc., the heating during curing is an organic base material. In addition, since the tendency to adversely affect the peripheral members increases, it is required to cure the adhesive at a lower temperature than in the case of the glass substrate. In addition, since the surface of the base material containing PET, PC, PEN, etc. is generally smoother than the glass substrate, the effect of physical anchoring effect (anchor effect) is small, so that high adhesive strength tends to be difficult to obtain. is there.

  Therefore, it is desired to improve the adhesive strength in a radical curable adhesive having low temperature curability. However, it is difficult to form a covalent bond with a silane coupling agent because a base material containing a thermoplastic resin such as PET, PC, PEN or the like easily forms a crystal part due to intermolecular interaction due to a benzene ring or the like. . Therefore, when these base materials are used, the method described in Patent Document 3 cannot provide a sufficient effect of improving the adhesive strength.

  Moreover, the base material containing thermoplastic resins, such as PET, PC, and PEN, has a larger thermal expansion coefficient than a glass substrate, and surface energy is also different from a glass substrate. Therefore, it is desirable to impart sufficient flexibility to the adhesive in order to improve wettability to the adherend and reduce internal stress. However, the method described in Patent Document 4 provides sufficient flexibility. However, further improvement in adhesive strength is desired.

  In the case of the method described in Patent Document 5, there is a problem that performance such as adhesive strength and connection resistance after the high temperature and high humidity test cannot be obtained sufficiently. Even by the method of dispersing the stress-absorbing particles described in Patent Document 6, a sufficient effect of improving the adhesive strength cannot be obtained particularly for a substrate containing a thermoplastic resin such as PET, PC, or PEN.

  Regarding the circuit connection material for connecting the substrate and the circuit member, in addition to sufficient adhesive force, connection characteristics for maintaining electrical connection between the circuit and the substrate are also required. Since the photopolymerization curable composition described in Patent Document 7 does not focus on the connection of circuit members, it is difficult to ensure electrical connectivity. Further, since the circuit member absorbs light, a photopolymerization-curable composition cannot be used in the circuit connection material.

  As described above, conventionally, when connecting circuit members having an organic base material having low heat resistance including PET, PC, PEN, etc., it is impossible to achieve both sufficiently high adhesive strength and connection reliability. Was the actual situation.

  Therefore, one of the objects of the present invention is to obtain excellent adhesive strength even when a circuit member having an organic substrate having low heat resistance such as PET, PC, PEN is connected at a low temperature. And it is providing the circuit connection material which can maintain the stable performance even after the reliability test of high temperature under high humidity for a long time.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have achieved both adhesive strength and connection resistance in connection between an organic base material including a thermoplastic resin having low heat resistance, such as PET, PC, and PEN, and a circuit member. In order to achieve this, it has been found that it is necessary to optimize the fluidity and mechanical strength of the circuit connecting material. As a result of further investigation based on such knowledge, it has been found that by applying a specific monofunctional radical polymerizable compound, the fluidity and mechanical strength of the circuit connecting material are optimized, and both adhesive strength and connection resistance can be achieved. The present invention has been completed.

  That is, the present invention includes (a) a thermoplastic resin, (b) a bifunctional or higher functional radical polymerizable compound, and (c) a monofunctional radical polymerizable compound represented by the following general formula (1) or (2). And (d) a radical polymerization initiator.

In formula (1), R ¹ is an aromatic hydrocarbon group which may have a substituent, an aliphatic hydrocarbon group which may have a substituent, or an alicyclic ring which may have a substituent. R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a plurality of R ² and R in the same molecule ⁴ may be the same or different, and n represents an integer of 1 to 20.

In formula (2), R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, a plurality of R ⁴ in the same molecule may be the same or different, and R ⁵ is a substituted group. The aromatic hydrocarbon group which may have a group is shown, and n shows the integer of 1-20.

  Since the circuit connection material contains the specific monofunctional radical polymerizable compound represented by the formula (1) or (2), the fluidity and the mechanical strength after curing are optimized, and as a result, It is possible to achieve both excellent adhesion strength and connection resistance not only in a conventional glass substrate but also in a low-temperature connection between an organic substrate having low heat resistance and a circuit member.

  The thermoplastic resin may contain a resin having a urethane bond and an ester bond. By using such a specific thermoplastic resin, the polarity of the circuit connecting material is increased, and the electrostatic interaction between the circuit connecting material and the glass substrate or the organic substrate is increased. Combined with the effect of the organic compound, the adhesive force is further improved.

  Moreover, the said thermoplastic resin may contain resin which has a glass transition temperature of 60 degreeC or more, and resin which has a glass transition temperature of -5 degreeC-40 degreeC. By using these thermoplastic resins having different glass transition temperatures in combination, the cohesive force and fluidity of the thermoplastic resin are optimized, and the adhesive force and the connection resistance can be compatible at a higher level.

  The circuit connecting material according to the present invention may further contain (f) a vinyl compound having a phosphate group and different from the above-mentioned bifunctional or higher radical polymerizable compound. Thereby, more excellent adhesive strength can be obtained under low temperature and short time curing conditions.

  The circuit connection material according to the present invention may further contain (e) conductive particles.

  The circuit connection material according to the present invention may be formed into a film to obtain a film-like circuit connection material. Moreover, this invention relates also to a circuit connection sheet provided with a base material and the said film-form circuit connection material formed on this base material.

  In another aspect, the present invention provides a first circuit member having a first circuit board and a first circuit electrode provided on the first circuit board, a second circuit board, and the second circuit board. A second circuit member having a second circuit electrode provided on the circuit board; and a first circuit electrode and a second circuit electrode interposed between the first circuit member and the second circuit member. It is related with a circuit connection body provided with the connection part which adhere | attaches a 1st circuit member and a 2nd circuit member so that and may be electrically connected. In the circuit connection body according to the present invention, the connection portion is a cured product of the circuit connection material according to the present invention. At least one of the first circuit board and the second circuit board may be an organic base material including a thermoplastic resin. The glass transition temperature of the thermoplastic resin may be 200 ° C. or less.

  Excellent adhesion strength and long-term reliability test not only when using a conventional glass substrate but also an organic substrate containing a thermoplastic resin because the connection part is a cured product of the circuit connection material according to the present invention. Later stable performance (especially adhesive strength and connection resistance) can be obtained.

  In still another aspect, the present invention provides a first circuit member having a first circuit board and a first circuit electrode provided on the first circuit board, a second circuit board, and the second circuit board. The first circuit electrode and the second circuit electrode are electrically connected by curing the circuit connecting material interposed between the second circuit member and the second circuit member provided on the circuit board. It is related with the connection method of a circuit member provided with the process of adhere | attaching a 1st circuit member and a 2nd circuit member so that it may be connected to. At least one of the first circuit board and the second circuit board may be an organic base material containing a thermoplastic resin. The glass transition temperature of the thermoplastic resin may be 200 ° C. or less.

  By adhering circuit members using the circuit connecting material according to the present invention, excellent adhesion strength and long-term reliability test are possible not only when using a conventional glass substrate but also when using an organic substrate containing a thermoplastic resin. Later stable performance (especially adhesive strength and connection resistance) can be obtained.

  The thermoplastic resin may contain at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. When the circuit board is an organic base material containing these specific thermoplastic resins, the wettability of the circuit connection material to the circuit board is improved, and further excellent adhesive strength and connection reliability can be obtained.

  According to the present invention, it is possible to achieve both excellent adhesive strength and connection resistance even when cured at low temperature on organic substrates with low heat resistance such as PET, PC, PEN, etc., in addition to glass substrates. Circuit connection materials that can maintain stable performance (adhesion strength and connection resistance) even after long-term reliability tests (high temperature and high humidity tests), film-like circuit connection materials using the same, circuit connection sheets, A circuit connection body and a circuit member connection method can be provided.

It is a schematic cross section showing one embodiment of a circuit connection sheet. It is a schematic cross section which shows one Embodiment of a circuit connection body.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as the case may be. However, the present invention is not limited to the following embodiments. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and overlapping descriptions may be omitted as appropriate.

  In the present specification, “(meth) acrylic acid” means acrylic acid or methacrylic acid corresponding to it, “(meth) acrylate” means acrylate or the corresponding methacrylate, and “(meth) acryloyl group” Means an acryloyl group or a corresponding methacryloyl group.

  In this specification, the “glass transition temperature (Tg)” of a thermoplastic resin or a circuit board is determined by using a viscoelasticity analyzer “RSA-3” (trade name) manufactured by TA Instruments, Inc. It means the value of the peak temperature of tan δ in the viscoelastic curve measured under the conditions of 5 ° C./min, frequency 10 Hz, measurement temperature −150 ° C. to 300 ° C.

  The circuit connecting material according to the present embodiment includes (a) a thermoplastic resin, (b) a bifunctional or higher radical polymerizable compound, and (c) a monofunctional compound represented by the following general formula (1) or (2). It contains a radically polymerizable compound, (d) a radical polymerization initiator, and (e) conductive particles as necessary.

In formula (1), R ¹ is an aromatic hydrocarbon group which may have a substituent, an aliphatic hydrocarbon group which may have a substituent, or an alicyclic ring which may have a substituent. R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a plurality of R ² and R in the same molecule ⁴ may be the same or different, and n represents an integer of 1 to 20. In formula (2), R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, a plurality of R ⁴ in the same molecule may be the same or different, and R ⁵ is a substituted group. The aromatic hydrocarbon group which may have a group is shown, and n shows the integer of 1-20.

In the formula (1), R ¹ is, for example, a residue obtained by removing a carboxyl group from a dibasic acid selected from the group consisting of hexahydrophthalic acid, cyclohexene-1,2-dicarboxylic acid, phthalic acid and butanedioic acid. It is preferable. n is preferably 1 to 15, more preferably 1 to 10. As the monofunctional radically polymerizable compound of the formula (1), N-acryloyloxyethyl hexahydrophthalimide, N-acryloyloxyethyl-1,2,3,6-tetrahydrophthalimide, N-acryloyloxyethyl-3, At least one compound selected from the group consisting of 4,5,6-tetrahydrophthalimide and N-acryloyloxyethylmaleimide is used.

In the formula (2), R ⁵ is selected from the group consisting of a phenyl group, a hydroxyl group and an alkyl group, for example. n is preferably 1 to 15, more preferably 1 to 10. The functional radical polymerizable compound of formula (2) is preferably at least one selected from the group consisting of hydroxyethylated o-phenylphenol acrylate, hydroxybutylated o-phenylphenol acrylate and hydroxyhexylated o-phenylphenol acrylate. Seed compounds are used.

  The amount of the monofunctional radically polymerizable compound represented by the formula (1) or (2) is preferably 2 to 30% by mass based on the mass of the thermoplastic resin. When the amount is 2% by mass or more, the fluidity of the circuit connection material is improved, and the increase in connection resistance can be further effectively suppressed. Moreover, the mechanical strength of a circuit connection material increases that this content is 30 mass% or less, and higher adhesive force can be obtained. From the same viewpoint, the lower limit of the amount of the monofunctional radically polymerizable compound represented by the formula (1) or (2) is more preferably 5% by mass, and further preferably 6% by mass. The upper limit of the amount of the radical polymerizable compound represented by the formula (1) or (2) is more preferably 20% by mass, and further preferably 7.5% by mass.

  (A) The weight average molecular weight of the thermoplastic resin of a component becomes like this. Preferably it is 5000-150,000. When the weight average molecular weight is in this range, a particularly excellent effect can be obtained in terms of film forming property of the circuit connecting material and compatibility with other components of the thermoplastic resin. From the same viewpoint, the weight average molecular weight of the thermoplastic resin is more preferably 10,000 to 80,000.

In this specification, a weight average molecular weight means the value measured using the calibration curve by a standard polystyrene from a gel permeation chromatograph (GPC) according to the conditions shown below.
(Measurement condition)
Device: GPC-8020 manufactured by Tosoh Corporation
Detector: RI-8020 manufactured by Tosoh Corporation
Column: Gelpack GL-A-160-S + GL-A150 manufactured by Hitachi Chemical Co., Ltd.
Sample concentration: 120mg / 3ml
Solvent: Tetrahydrofuran Injection volume: 60 μl
Pressure: 30 kgf / cm ²
Flow rate: 1.00 ml / mim

  The thermoplastic resin (a) may be a resin having a urethane bond and an ester bond in the same molecule (hereinafter sometimes referred to as “polyester urethane resin”). The urethane bond has an effect of improving the mechanical strength of the resin. The ester bond has an effect of improving the polarity of the resin. By applying polyester urethane resin having these in the same molecule to circuit connection material, improvement of connection reliability by improving mechanical strength of cured product and further improvement of adhesion to substrate by increasing polarity of resin Can be achieved.

  The polyester urethane resin can be obtained, for example, by a reaction between a polyester polyol and a diisocyanate.

  The polyester polyol used for the synthesis | combination of a polyester urethane resin can be obtained by reaction of dicarboxylic acid and diol, for example. Examples of the dicarboxylic acid include terephthalic acid, isophthalic acid, phthalic acid, adipic acid, and sebacic acid. Examples of the diol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, triethylene glycol and the like. These can be used singly or in combination.

  Examples of the diisocyanate compound used for the synthesis of the polyester urethane resin include 2,4-tolylene diisocyanate, 3,3′-dimethyl-4,4′-biphenylene diisocyanate, 1,6-hexamethylene diisocyanate, and 1,3-phenylene. Diisocyanate, 1,4-phenylene diisocyanate, naphthalene-1,5-diisocyanate, 3,3′-dimethyldiphenylmethane-4,4′-diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, 4,4 ′ -Diphenylmethane diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, toluene-2,6-diisocyanate, toluene-2,4-diisocyanate, triethylhexamethylene diiso Selected from Aneto the group consisting of m- xylene diisocyanate. These can be used singly or in combination.

  Preferable specific examples of the thermoplastic resin that can be included in the circuit connecting material include phenoxy resin, polyurethane resin, butyral resin, acrylic resin, polyimide resin, and the like in addition to the polyester urethane resin.

  The circuit connection material which concerns on this embodiment may contain 2 or more types of thermoplastic resins as (a) component. In particular, it is preferable that the thermoplastic resin includes a first resin having a glass transition temperature (Tg) of 60 ° C. or higher and a second resin having a glass transition temperature (Tg) of −5 ° C. to 40 ° C. . The glass transition temperature of the first resin is more preferably 60 ° C to 90 ° C, and further preferably 65 ° C to 85 ° C. By using two or more types of thermoplastic resins with different glass transition temperatures, the fluidity and mechanical strength of the circuit connection material are further optimized to achieve a higher level of good connection resistance and sufficient adhesion. Can be compatible. When the glass transition temperature of the first resin is 60 ° C. or higher, the heat resistance of the thermoplastic resin is improved, and more excellent connection reliability is obtained. When the glass transition temperature of the first resin is 90 ° C. or lower, the fluidity of the thermoplastic resin is particularly improved, and both the connection resistance and the adhesive force can be achieved at a higher level. On the other hand, when the glass transition temperature of the second resin is −5 ° C. or higher, the heat resistance of the thermoplastic resin is particularly improved, and better connection reliability is obtained. When the glass transition temperature of the second resin is 40 ° C. or lower, the fluidity of the thermoplastic resin is particularly improved, and both the connection resistance and the adhesive force can be achieved at a higher level.

  For example, both of the first resin and the second resin may be a polyester urethane resin, or may be a combination of a polyester urethane resin as the first resin or the second resin and a resin other than the polyester. . The Tg of the polyester urethane resin can be prepared based on the type of raw material.

  Even when one kind of resin is used as the thermoplastic resin, it is possible to control the glass transition temperature of the resin according to the synthesis conditions and improve the fluidity of the thermoplastic resin. However, in this case, the molecular weight of the thermoplastic resin may decrease, and the mechanical strength of the cured product may decrease.

  The thermoplastic resin is composed of 5 to 60% by mass of the second resin having a glass transition temperature of −5 ° C. to 40 ° C. and the remaining first resin based on the mass of the entire thermoplastic resin. Is preferred. If the ratio of the second resin is less than 5% by mass, the adhesive strength tends to decrease after the moisture resistance test. If the ratio of the second resin exceeds 60% by mass, the heat resistance of the circuit connecting material decreases. Tend to. From the same viewpoint, the ratio of the second resin is more preferably 10 to 40% by mass.

  (A) The amount of the thermoplastic resin is 5% by mass or more and 80% by mass or less based on the mass of the adhesive component (components other than the conductive particles and insulating particles used as necessary among the circuit connecting materials). It is preferable that it is 15 mass% or more and 70 mass% or less. When this amount is 5% by mass or more, there is a tendency that a better film-forming property of the circuit connecting material is obtained. When this amount is 80% by mass or less, more excellent fluidity of the film-like circuit connecting material. Tends to be obtained.

  Examples of the (b) component bifunctional or higher radical polymerizable compound contained in the circuit connecting material include two or more radical polymerizable functional groups such as a vinyl group, a (meth) acryloyl group, an aryl group, and a maleimide group. The compound which has can be used suitably.

  The bifunctional or higher-functional radical polymerizable compound includes, for example, epoxy (meth) acrylate, urethane (meth) acrylate, polyether (meth) acrylate, polyester (meth) acrylate, 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 EO-modified bifunctional (meth) acrylate, isocyanuric acid EO-modified trifunctional (meth) acrylate, bisphenoxyethanol fluorene acrylate, bisphenol fluor Epoxy (meth) acrylate obtained by adding (meth) acrylic acid to glycidyl group of range glycidyl ether, epoxy obtained by adding (meth) acrylic acid to glycidyl group of bisphenol fluorenediglycidyl ether (Meth) acrylate, a compound obtained by adding ethylene glycol or propylene glycol to a glycidyl group of bisphenol fluorenediglycidyl ether, a compound obtained by introducing a (meth) acryloyloxy group, and the following general formula (A) or (B) It is selected from the group consisting of compounds represented by:

In formula (A), R ³¹ and R ³² each independently represent a hydrogen atom or a methyl group, and a and b each independently represent an integer of 1 to 8.

In formula (B), R ³³ and R ³⁴ each independently represent a hydrogen atom or a methyl group, and c and d each independently represent an integer of 0 to 8.

  As the radically polymerizable compound of component (b), a compound that becomes a solid state having no fluidity, such as waxy, waxy, crystalline, glassy, powdery, etc. when left alone at 30 ° C. may be used. it can. Specific examples of such radically polymerizable compounds include N, N′-methylenebisacrylamide, diacetone acrylamide, N-methylolacrylamide, N-phenylmethacrylamide, 2-acrylamido-2-methylpropanesulfonic acid, Tris (2-acryloyloxyethyl) isocyanurate, N-phenylmaleimide, N- (o-methylphenyl) maleimide, N- (m-methylphenyl) maleimide, N- (p-methylphenyl) -maleimide, N- ( o-methoxyphenyl) maleimide, N- (m-methoxyphenyl) maleimide, N- (p-methoxyphenyl) -maleimide, N-methylmaleimide, N-ethylmaleimide, N-octylmaleimide, 4,4′-diphenylmethanebis Maleimide, m-pheny Bismaleimide, 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide, 4-methyl-1,3-phenylenebismaleimide, N-methacryloxymaleimide, N-acryloxymaleimide 1,6-bismaleimide- (2,2,4-trimethyl) hexane, N-methacryloyloxysuccinimide, N-acryloyloxysuccinimide, 2-naphthyl methacrylate, 2-naphthyl acrylate, pentaerythritol tetraacrylate, Divinylethyleneurea, divinylpropyleneurea, 2-polystyrylethyl methacrylate, N-phenyl-N ′-(3-methacryloyloxy-2-hydroxypropyl) -p-phenylenediamine, N-phenyl-N ′-(3-acryloyl) Oxy -Hydroxypropyl) -p-phenylenediamine, tetramethylpiperidyl methacrylate, tetramethylpiperidyl acrylate, pentamethylpiperidyl methacrylate, pentamethylpiperidyl acrylate, octadecyl acrylate, Nt-butylacrylamide, diacetone acrylamide, N- (hydroxymethyl) ) Acrylamide, compounds represented by the following general formula (C), (D), (E), (F), (H), (I), (J), (K) or (L). .

  In formula (C), e represents an integer of 1 to 10.

In formula (E), R ⁷ and R ⁸ each independently represent a hydrogen atom or a methyl group, and g represents an integer of 15 to 30.

In formula (F), each R ⁹ independently represents a hydrogen atom or a methyl group.

In formula (G), each R ¹⁰ independently represents a hydrogen atom or a methyl group, and h represents an integer of 1 to 10.

In formula (H), each R ¹¹ independently represents a hydrogen atom or an organic group represented by the following general formula (i) or (ii), and i represents an integer of 1 to 10.

・・・（Ｉ）

... (I)

In the formula (I), R ¹² represents a hydrogen atom or an organic group represented by the following general formula (iii) or (iv), and j represents an integer of 1 to 10. A plurality of R ¹² in the same molecule may be the same or different.

  As the radically polymerizable compound of component (b), urethane (meth) acrylate can be used alone or in combination with other radically polymerizable compounds. By using urethane (meth) acrylate, the flexibility of the cured product is improved, and the adhesive strength to organic substrates such as PET, PC, PEN and the like can be further improved.

  Although there is no restriction | limiting in particular as urethane (meth) acrylate, The compound represented by the following general formula (J) is preferable. The urethane (meth) acrylate represented by the formula (J) is obtained by a condensation reaction between an aliphatic or alicyclic diisocyanate and at least one aliphatic or alicyclic ester diol or aliphatic or alicyclic carbonate diol. Can be obtained.

In formula (J), R ¹⁵ and R ¹⁶ each independently represent a hydrogen atom or a methyl group, R ¹⁷ represents an ethylene group or a propylene group, R ¹⁸ represents a saturated aliphatic group or a saturated alicyclic group, R ¹⁹ represents a saturated aliphatic group or saturated alicyclic group having an ester group, or a saturated aliphatic group or saturated alicyclic group having a carbonate group, and k represents an integer of 1 to 40. In the formula, a plurality of R ¹⁵ , R ¹⁶ , R ¹⁷ , and R ¹⁸ in the same molecule may be the same or different. R ¹⁸ is a residue of an aliphatic or alicyclic diisocyanate, and R ¹⁹ is a residue of an aliphatic or alicyclic ester diol or an aliphatic or alicyclic carbonate diol.

  The aliphatic diisocyanate constituting the urethane (meth) acrylate is, for example, tetramethylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, 2-methylpentane-1,5-diisocyanate, 3-methylpentane-1,5-diisocyanate, 2, 2,4-trimethylhexamethylene-1,6-diisocyanate, 2,4,4-trimethylhexamethylene-1,6-diisocyanate, isophorone diisocyanate, cyclohexyl diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, and hydrogenation Selected from the group consisting of trimethylxylylene diisocyanate.

  The aliphatic ester diol constituting the urethane (meth) acrylate may be a polyester diol obtained by dehydration condensation of a glycol and a dibasic acid or an acid anhydride thereof, or a cyclic ester compound such as ε-caprolactone. It may be an ester diol obtained by ring-opening polymerization. These are used individually by 1 type or in combination of multiple types.

  The glycols used to obtain the polyester diol are, for example, ethylene glycol, propylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl. Glycol, 1,2-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,4-dimethyl-2,4 -Pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,2-hexanediol, 1,5-hexanediol, 1,6-hexanediol, 2,5-hexanediol, 2-ethyl -1,3-hexanediol, 2,5-dimethyl-2,5-hexanediol, 1,2-octane Diol, 1,8-octanediol, 1,7-heptanediol, 1,9-nonanediol, 1,2-decanediol, 1,10-decanediol, 1,12-decanediol, dodecanediol, pinacol, 1 , 4-butynediol, triethylene glycol, diethylene glycol, dipropylene glycol, cyclohexane dimethanol, and 1,4-cyclohexane dimethanol. Examples of the dibasic acid include adipic acid, 3-methyladipic acid, 2,2,5,5-tetramethyladipic acid, maleic acid, fumaric acid, succinic acid, 2,2-dimethylsuccinic acid, 2-ethyl- 2-methylsuccinic acid, 2,3-dimethylsuccinic acid, oxalic acid, malonic acid, methylmalonic acid, ethylmalonic acid, butylmalonic acid, dimethylmalonic acid, glutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, It is selected from the group consisting of 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, 2,4-dimethylglutaric acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid.

  The polycarbonate diol constituting the urethane (meth) acrylate can be obtained, for example, by a reaction between at least one kind of the above glycols and phosgene. The polycarbonate diol obtained by reaction of glycols and phosgene is used individually by 1 type or in combination of 2 or more types.

  The weight average molecular weight of the urethane (meth) acrylate may be 5000 or more and less than 30000 from the viewpoint of improving the adhesive strength to an organic substrate containing a resin such as PET, PC, or PEN. A urethane (meth) acrylate having a weight average molecular weight within such a numerical range has both moderate flexibility and cohesion. As a result, the adhesive strength with organic substrates such as PET, PC, PEN and the like can be improved, and excellent connection reliability can be obtained. From the same viewpoint, the weight average molecular weight of urethane (meth) acrylate is more preferably 80000 or more and less than 25000, and further preferably 10,000 or more and less than 20000. When the weight average molecular weight of the urethane (meth) acrylate is 5000 or more, more excellent flexibility tends to be obtained. When the weight average molecular weight of the urethane (meth) acrylate is less than 30000, the circuit connection material Good fluidity tends to be obtained.

  In the circuit connecting material, the total amount of the bifunctional or higher functional radical polymerizable compound (b) and the monofunctional radical polymerizable compound (c) is 50 to 250 masses per 100 parts by mass of the thermoplastic resin. Part, preferably 60 to 150 parts by weight. When this amount is 50 parts by mass or more, the heat resistance after curing tends to be further improved, and when this amount is 250 parts by mass or less, better film formability of the circuit connecting material tends to be obtained. is there.

  The (d) radical polymerization initiator contained in the circuit connecting material may be a compound that generates radicals by external energy application, such as an organic peroxide or an azo compound. The radical polymerization initiator is preferably an organic peroxide having a 1 minute half-life temperature of 90 ° C. or more and 175 ° C. or less and a molecular weight of 180 or more and 1000 or less from the viewpoints of stability, reactivity, and compatibility. When the one-minute half-life temperature of the radical polymerization initiator is within this range, a circuit connection material that is excellent in storage stability, sufficiently high in radical polymerization, and cured in a short time can be obtained.

  Examples of the radical polymerization initiator include 1,1,3,3-tetramethylbutylperoxyneodecanoate, di (4-t-butylcyclohexyl) peroxydicarbonate, and di (2-ethylhexyl) peroxydicarbonate. , Cumylperoxyneodecanoate, dilauroyl peroxide, 1-cyclohexyl-1-methylethylperoxyneodecanoate, t-hexylperoxyneodecanoate, t-butylperoxyneodecanoate, t -Butyl peroxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethyl Xanoate, t-butylperoxyneoheptanoate, t-amylperoxy-2-ethylhexanoate, di-t-butylperoxyhexahydroterephthalate, t-amylperoxy-3,5,5-trimethylhexa Noate, 3-hydroxy-1,1-dimethylbutylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, t-amylperoxyneodecanoate , T-amylperoxy-2-ethylhexanoate, di (3-methylbenzoyl) peroxide, dibenzoyl peroxide, di (4-methylbenzoyl) peroxide, t-hexylperoxyisopropyl monocarbonate, t- Butyl peroxymaleic acid, t-butyl peroxy-3,5, -Trimethylhexanoate, t-butylperoxylaurate, 2,5-dimethyl-2,5-di (3-methylbenzoylperoxy) hexane, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexyl Peroxybenzoate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxybenzoate, dibutylperoxytrimethyladipate, t-amylperoxynormal octoate, t-amylperoxyisono Organic peroxides such as nanoate, t-amylperoxybenzoate, and 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), etc. Selected from the group consisting of: These compounds are used alone or in combination of two or more.

  As the radical polymerization initiator, a compound that generates radicals by light irradiation of 150 nm or more and 750 nm or less can be used. Such compounds include, for example, Photoinitiation, Photopolymerization, and Photocuring, J. Mol. -P. The α-acetaminophenone derivative and the phosphine oxide derivative described in Fouassier, Hanser Publishers (1995, p17 to p35) are more preferable because of their high sensitivity to light irradiation. These compounds are used alone or in combination with the above organic peroxides or azo compounds.

  The amount of the radical polymerization initiator is 0.5% by mass or more and 40% by mass or less based on the mass of the adhesive component (components other than the conductive particles and insulating particles used as necessary among the circuit connection materials). It is preferably 1% by mass or more and 30% by mass or less, more preferably 2% by mass or more and 20% by mass or less. When the amount of the radical polymerization initiator is 0.5% by mass or more, the circuit connecting material tends to be sufficiently cured, and when the amount of the radical polymerization initiator is 40% by mass or less, storage stability is obtained. Tend to improve.

  The (e) conductive particles contained in the circuit connecting material may be particles whose whole or surface is composed of a conductive material. When the circuit connection material is used for connection of a circuit member having connection terminals (circuit electrodes), it is preferable that the average particle diameter of the conductive particles is smaller than the distance between the connection terminals.

  Examples of the conductive particles include metal particles such as Au, Ag, Ni, Cu, Pd, and solder, and carbon particles. The conductive particles may be composite particles having particles such as non-conductive glass, ceramic, or plastic as a core and metal layers, metal particles, or carbon particles covering the core. When the conductive particles are the composite particles or the heat-meltable metal particles, the conductive particles are deformed by heating and pressurization, so that the contact area with the electrode is increased at the time of connection, and particularly high reliability is obtained. The conductive particles may be, for example, particles having copper particles and a silver layer that covers the copper particles. As the conductive particles, a metal powder having a shape in which a large number of fine metal particles are connected in a chain shape as described in JP-A-2005-116291 can be used.

  The conductive particle may have an insulating layer made of an insulating material covering the conductive surface, or an insulating particle covering the conductive surface, or a method such as hybridization. By using such conductive particles, short circuit due to contact between adjacent conductive particles is less likely to occur.

  The average particle diameter of the conductive particles is preferably 1 μm or more and 18 μm or less from the viewpoint of dispersibility and conductivity.

  The amount of the conductive particles is not particularly limited, but is preferably 0.1% by volume to 30% by volume based on the total volume of the circuit connecting material, and is 0.1% by volume to 10% by volume. It is more preferable. When the amount of the conductive particles is 0.1% by volume or more, the conductivity tends to be further improved, and when the amount of the conductive particles is 30% by volume or less, a short circuit tends to be less likely to occur. Here, “volume%” is calculated based on the volume of each component before curing at 23 ° C. The volume of each component can be determined by conversion from mass using specific gravity. Alternatively, do not dissolve or swell the component whose volume is to be obtained, put an appropriate solvent (water, alcohol, etc.) that wets the component well into the graduated cylinder, put the component there, and add the increased volume to the component. It can also obtain | require as a volume of.

  The circuit connecting material according to the present embodiment may contain (e) a vinyl compound having one or more phosphate groups in the molecule separately from the component (a) and the component (b). As a vinyl compound which has a phosphoric acid group, the compound represented by the following general formula (N), (O) or (P) is mentioned, for example.

In formula (N), R ²⁰ represents a (meth) acryloyloxy group, R ²¹ represents a hydrogen atom or a methyl group, and l and m each independently represent an integer of 1 to 8. A plurality of R ²⁰ , R ²¹ , l and m in the same molecule may be the same or different.

In the formula (O), R ²² represents a (meth) acryloyloxy group, and s, o and p each independently represent an integer of 1 to 8. A plurality of R ²² s, o and p in the same molecule may be the same or different.

In formula (P), R ²³ represents a (meth) acryloyloxy group, R ²⁴ represents a hydrogen atom or a methyl group, and q and r each independently represents an integer of 1 to 8. A plurality of R ²⁴ and q in the same molecule may be the same or different.

  Specific examples of the vinyl compound (f) include acid phosphooxyethyl (meth) acrylate, acid phosphooxypropyl (meth) acrylate, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, and acid phosphooxypolyoxypropylene. Examples include glycol mono (meth) acrylate, 2,2′-di (meth) acryloyloxydiethyl phosphate, EO-modified phosphoric acid di (meth) acrylate, phosphoric acid-modified epoxy (meth) acrylate, and vinyl phosphate.

  In the circuit connecting material according to the present embodiment, the content of the vinyl compound as the component (f) is preferably 0.1 to 15 parts by mass with respect to 50 parts by mass of the thermoplastic resin. More preferably, it is part by mass. If this content is 0.1 parts by mass or more, an excellent effect of adhesive strength tends to be obtained, and if this content is 15 parts by mass or less, the physical properties of the circuit connection material after curing are reduced. It is difficult to obtain an excellent reliability effect.

  The circuit connecting material according to the present embodiment may contain a coupling agent in order to improve the adhesive force to a glass substrate or the like. As the coupling agent, a normal compound can be used without particular limitation, but a silane compound having one or more alkoxy acid groups in the molecule is preferable. Examples of preferred coupling agents include 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyltriethoxysilane, and the like.

  The amount of the coupling agent is preferably 0.1 to 15 parts by mass and more preferably 0.5 to 10 parts by mass with respect to 50 parts by mass of the thermoplastic resin. When the amount of the coupling agent is 0.1 parts by mass or more, the effect of improving the adhesive strength tends to be larger, and when the amount of the coupling agent is 15 parts by mass or less, the cured circuit connection material There is a tendency that physical properties are hardly lowered and an excellent reliability effect is obtained.

  The circuit connecting material can contain insulating particles for the purpose of improving the stress relaxation effect or improving the mechanical strength of the circuit connecting material. As the insulating fine particles, ordinary particles can be used without particular limitation. For example, silicone fine particles, boron nitride, mica, alumina, organic fine particles, rubber particles and the like can be suitably used.

  The amount of the insulating fine particles in the circuit connecting material is preferably 0.5 to 30 parts by mass and more preferably 1 to 25 parts by mass with respect to 50 parts by mass of the thermoplastic resin. When the amount of the insulating fine particles is 0.5 parts by mass or more, there is a tendency to obtain an excellent adhesive strength effect, and when the amount of the insulating fine particles is 30 parts by mass or less, the cured circuit connection material There is a tendency that physical properties are hardly lowered and an excellent reliability effect is obtained.

  The circuit connection material may contain a stabilizer for control of the curing rate and storage stability. As the stabilizer, ordinary compounds can be used without any particular limitation. 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, 4-hydroxy- Aminoxyl derivatives such as 2,2,6,6-tetramethylpiperidine-1-oxyl, hindered amine derivatives such as tetramethylpiperidyl methacrylate, and the like are preferable.

  The amount of the stabilizer is preferably 0.01 to 30% by mass, and more preferably 0.05 to 10% by mass based on the mass of the thermoplastic resin. If the amount of the stabilizer is 0.01% by mass or more, the effect due to the addition tends to be easily obtained, and if the amount of the stabilizer is 30% by mass or less, compatibility with other components is improved. Tend to.

  The circuit connecting material may be in the form of a paste when it is liquid at room temperature. The circuit connection material that is solid at room temperature may be made into a paste by heating or adding a solvent. As the solvent that can be used, a solvent that is not reactive with each component constituting the circuit connecting material and exhibits sufficient solubility is preferable. The boiling point of the solvent at normal pressure is preferably 50 ° C. or higher and 150 ° C. or lower. If the boiling point of the solvent is less than 50 ° C., the tendency to volatilize when the circuit connecting material is allowed to stand at room temperature tends to be difficult to use in an open system. When the boiling point of the solvent exceeds 150 ° C., it is difficult to volatilize the solvent, and the effect of improving reliability after bonding may be reduced.

  The circuit connection material can be formed into a film and used as a film adhesive. A solution obtained by adding a solvent or the like to the circuit connection material as necessary is applied on a peelable substrate such as a fluororesin film, a polyethylene terephthalate film, or a release paper, or a substrate such as a nonwoven fabric is impregnated with the above solution. It is made to mount on a peelable base material, a solvent etc. are removed and it can be used as a film adhesive. Use in the form of a film is more convenient from the viewpoint of handleability.

  The circuit connection material which concerns on this embodiment can be used as an anisotropic conductive adhesive, a silver paste, or a silver film, for example.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of a circuit connection sheet including a film-like circuit connection material. A circuit connection sheet 100 shown in FIG. 1 includes a sheet-like base material 12 and a film-like circuit connection material 10 provided in close contact with the main surface of the base material 12.

  The film-like circuit connection material 10 is obtained by forming the circuit connection material according to the above-described embodiment into a film shape. The thickness of the film-like circuit connecting material is not particularly limited, but is, for example, 3 to 50 μm.

  As the substrate 12, for example, a peelable substrate such as a fluororesin film, a polyethylene terephthalate film, or a release paper can be used. Although the thickness in particular of the base material 12 is not restrict | limited, For example, it is 10-100 micrometers.

  FIG. 2 is a schematic cross-sectional view showing an embodiment of a circuit connector. The circuit connection body 200 shown in FIG. 2 includes a first circuit member 20, a second circuit member 30, and a connection portion 16 formed between the first circuit member 20 and the second circuit member 30. Composed.

  The connection part 16 is, for example, a cured product formed by curing the circuit connection material according to the above-described embodiment by heating. The connecting portion 16 does not have to reach full curing (the highest degree of curing that can be achieved under predetermined curing conditions), and may be in a partially cured state as long as there is no practical problem.

  The first circuit member 20 includes a first circuit board 21 and a first circuit electrode 22 provided on the main surface 21 a of the first circuit board 21. The second circuit member 30 includes a second circuit board 31 and a second circuit electrode 32 provided on the main surface 31 a of the second circuit board 31. The first circuit board 21 and the second circuit board 31 are connected via the connection portion 16 so that the first circuit electrode 22 and the second circuit electrode 32 face each other. An insulating layer may be formed on the main surfaces 21a and 31a of the first circuit board 21 and the second circuit board 31, respectively.

  At least one of the first circuit board 21 and the second circuit board 31 may be an organic base material including a thermoplastic resin having a glass transition temperature of 200 ° C. or lower. The thermoplastic resin having a glass transition temperature of 200 ° C. or less includes, for example, at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. Even when a circuit member having an organic base material containing such a thermoplastic resin is connected, the circuit connection material according to the present embodiment can obtain sufficiently excellent adhesive strength and connection reliability. it can. One of the reasons is considered that the circuit connection material according to the present embodiment has high wettability with respect to the organic base material containing these thermoplastic resins. From the same viewpoint, at least one of the first circuit board 21 and the second circuit board 31 may be an organic base material having a glass transition temperature of 200 ° C. or less.

  One of the first circuit board 21 and the second circuit board 31 includes at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate, and the other circuit board is polyimide. It is preferable to contain resin and / or polyethylene terephthalate. By using such a combination of circuit boards, adhesion strength and connection reliability can be further improved.

  In addition to the above, an inorganic substrate such as a semiconductor, glass, or ceramic, or an organic substrate such as polyimide or polycarbonate can be used in combination.

  The circuit connection body 100 hardens the circuit connection material (for example, the film-like circuit connection material 10) interposed between the first circuit member 20 and the second circuit member 30, and the first circuit electrode 22 is cured. And the second circuit electrode 32 can be manufactured by a method including a step of bonding the first circuit member 20 and the second circuit member 30 so as to be electrically connected.

  In the circuit connection step, it is preferable to cure the circuit connection material by heating and pressing. The heating temperature is preferably 100 ° C. or higher and 200 ° C. or lower. The pressure is preferably in a range that does not damage the adherend (first and second circuit members), and is generally 0.1 MPa or more and 10 MPa or less. These heating and pressurization are preferably performed in a range of 0.5 seconds to 120 seconds. According to the circuit connection material according to the present embodiment, it is possible to perform circuit connection with high reliability even under low temperature conditions such as 110 ° C. or higher and 190 ° C. or lower, or 90 ° C. or higher and 150 ° C. or lower. From the same viewpoint, the heating and heating time are more preferably 0.5 seconds or more and 60 seconds or less, and the pressure is more preferably 0.1 MPa or more and 5 MPa or less. The connection conditions may be, for example, 110 ° C., 3 MPa, and 10 seconds.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

1. Material (a) Thermoplastic resin Polyester urethane resin A
Using isophthalic acid (manufactured by Aldrich) as the dicarboxylic acid, neopentyl glycol (manufactured by Aldrich) as the diol, and 4,4′-diphenylmethane diisocyanate (manufactured by Aldrich) as the isocyanate, A polyester urethane resin A having a mass ratio of neopentyl glycol / 4,4′-diphenylmethane diisocyanate of 48/37/15 was synthesized. The number average molecular weight of the obtained polyester urethane resin A was 25000, and the glass transition temperature was 73 ° C. Polyester urethane resin A (PEU-A) was dissolved in a mixed solvent prepared by mixing methyl ethyl ketone and toluene at 1: 1 (mass ratio) to obtain a 40% by mass polyester urethane resin solution.

Polyester urethane resin B
Using terephthalic acid (manufactured by Aldrich) and adipic acid (manufactured by Aldrich) as the dicarboxylic acid, using neopentyl glycol (manufactured by Aldrich) as the diol, and using 4,4′-diphenylmethane diisocyanate (manufactured by Aldrich) as the isocyanate Thus, polyester urethane resin B having a molar ratio of terephthalic acid / adipic acid / neopentyl glycol / 4,4′-diphenylmethane diisocyanate in the starting material of 11/25/38/26 was synthesized. The number average molecular weight of the obtained polyester urethane resin B was 40000, and the glass transition temperature was 10 ° C. Polyester urethane resin B (PEU-B) was dissolved in a mixed solvent prepared by mixing methyl ethyl ketone and toluene at 0.82: 0.18 (mass ratio) to obtain a polyester urethane resin solution having a concentration of 40 mass%. Obtained.

Polyester urethane resin C
Using terephthalic acid (manufactured by Aldrich) and adipic acid (manufactured by Aldrich) as the dicarboxylic acid, using neopentyl glycol (manufactured by Aldrich) as the diol, and using 4,4′-diphenylmethane diisocyanate (manufactured by Aldrich) as the isocyanate Thus, a polyester urethane resin C having a molar ratio of terephthalic acid / adipic acid / neopentyl glycol / 4,4′-diphenylmethane diisocyanate in the starting material of 34/14/38/14 was synthesized. The number average molecular weight of the obtained polyester urethane resin C was 32000, and the glass transition temperature was 18 ° C. Polyester urethane resin C (PEU-C) was dissolved in a mixed solvent prepared by mixing methyl ethyl ketone and toluene at 1: 1 (mass ratio) to obtain a polyester urethane resin solution having a concentration of 30% by mass.

Phenoxy resin Phenoxy resin (trade name: YP-50 (manufactured by Tohto Kasei Co., Ltd.), weight average molecular weight: 60000, glass transition temperature: 80 ° C.) 40 parts by mass is dissolved in 60 parts by mass of methyl ethyl ketone to obtain a solid content of 40% by mass. A phenoxy resin solution was prepared.

(B) Bifunctional or higher radical polymerizable compound UA1: Urethane acrylate 1
Poly (1,6-hexanediol carbonate) with a number average molecular weight of 1000 (trade name: DURANOL T5652, Asahi Kasei) in a reaction vessel equipped with a stirrer, thermometer, reflux condenser with calcium chloride drying tube, and nitrogen gas introduction tube Chemicals Co., Ltd.) 2500 parts by mass (2.50 mol) and isophorone diisocyanate (Sigma Aldrich) 666 parts by mass (3.00 mol) were uniformly added dropwise over 3 hours. After sufficiently introducing nitrogen gas into the reaction vessel, the reaction solution was heated to 70 to 75 ° C. to advance the reaction.

  Subsequently, 0.53 parts by mass of hydroquinone monomethyl ether (manufactured by Sigma Aldrich) and 5.53 parts by mass of dibutyltin dilaurate (manufactured by Sigma Aldrich) were added, and further 238 masses of 2-hydroxyethyl acrylate (manufactured by Sigma Aldrich). Part (2.05 mol) was added, and the reaction was allowed to proceed for 6 hours at 70 ° C. in an air atmosphere to produce urethane acrylate 1 (UA1).

UA2: Urethane acrylate 2
In a reaction vessel equipped with a stirrer, thermometer, reflux condenser with calcium chloride drying tube, and nitrogen gas introduction tube, 1000 parts by mass of methyl ethyl ketone and polycaprolactone diol having a number average molecular weight of 1000 (trade name: Plaxel 210N, Daicel Chemical Industries) 2500 parts by mass (manufactured by Co., Ltd.) and 666 parts by mass (3.00 mol) of isophorone diisocyanate (manufactured by Sigma-Aldrich) were uniformly added dropwise over 3 hours. After sufficiently introducing nitrogen gas into the reaction vessel, the reaction solution was heated to 70 to 75 ° C. to advance the reaction.

  Subsequently, 0.53 parts by mass of hydroquinone monomethyl ether (manufactured by Sigma Aldrich) and 5.53 parts by mass of dibutyltin dilaurate (manufactured by Sigma Aldrich) were added, and further 238 masses of 2-hydroxyethyl acrylate (manufactured by Sigma Aldrich). Part (2.05 mol) was added, and the reaction was allowed to proceed at 70 ° C. for 6 hours in an air atmosphere to produce urethane acrylate 2 (UA2).

M-215
Isocyanuric acid EO-modified diacrylate (manufactured by Toagosei Co., Ltd.)

(C) Monofunctional radically polymerizable compound MAC1
In a reaction vessel equipped with a stirrer, thermometer, reflux condenser with calcium chloride drying tube, and water separator, 310 parts by mass (2.00 mol) of hexahydrophthalic anhydride (manufactured by Sigma-Aldrich) was toluene. A reaction solution was prepared by dissolving in 500 parts by mass. While heating the reaction solution at 70 ° C., 130 parts by mass (2.00 mol) of ethanolamine (manufactured by Nippon Shokubai Co., Ltd.) was added dropwise over 30 minutes, and then the reaction solution was stirred at 120 ° C. for 5 hours to produce. The water was separated. After cooling, 160 parts by mass (2.20 mol) of acrylic acid (manufactured by Sigma Aldrich), 0.2 part by mass of hydroquinone monomethyl ether (manufactured by Sigma Aldrich), and 12 parts by mass of sulfuric acid were added, and further 5 at 120 ° C. The reaction solution was stirred for a period of time, and the generated water was azeotropically dehydrated. After cooling, the reaction solution is washed with water using a separatory funnel, and the residual toluene is removed by distillation under reduced pressure to obtain a monofunctional radical polymerizable compound (MAC1, N-acryloyl) represented by the following formula (1a). Oxyethylhexahydrophthalimide) was obtained.

MAC2
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser with a calcium chloride drying tube, and a water separator, 340 parts by mass (2.00 mol) of orthophenylphenol (manufactured by Sanko Co., Ltd.) was added to 500 parts by mass of ethanol. To prepare a reaction solution. While heating the reaction solution at 70 ° C., 12 parts by mass of sulfuric acid was added dropwise over 30 minutes. Thereafter, the reaction solution was further stirred at 120 ° C. for 5 hours to separate the produced water. After cooling, 160 parts by mass (2.20 mol) of acrylic acid (manufactured by Sigma Aldrich), 0.2 part by mass of hydroquinone monomethyl ether (manufactured by Sigma Aldrich) and 12 parts by mass of sulfuric acid were added, and further at 120 ° C. for 5 hours. The reaction solution was stirred, and the produced water was azeotropically dehydrated. After cooling, the reaction solution is washed with water using a separatory funnel, and the residual ethanol is removed by distillation under reduced pressure to obtain a monofunctional radical polymerizable compound (MAC2, hydroxyethylated) represented by the following formula (2a). o-phenylphenol acrylate) was obtained.

(D) Radical polymerization initiator Dilauroyl peroxide (Perroyl L, manufactured by NOF Corporation)

(E) Conductive particles An average particle composed of polystyrene particles as nuclei, a 0.2 μm thick nickel layer covering the surface of the polystyrene particles, and a 0.02 μm thick gold layer provided outside the nickel layer. Conductive particles having a diameter of 4 μm and a specific gravity of 2.5 were prepared.

(F) Vinyl compound having a phosphate group 2-Methacryloyloxyethyl phosphate (trade name: Light Ester P-2M, manufactured by Kyoeisha Chemical Co., Ltd.)

(Insulating fine particles)
Core-shell type silicone fine particles (trade name: KMP-600, average particle size: 5 μm, manufactured by Shin-Etsu Chemical Co., Ltd.)

2. Production of Film-like Circuit Connection Material Each component shown in Table 1 is blended at a solid mass ratio shown in Table 1, and further, the above conductive particles are blended and dispersed, so that the circuit connection materials of each Example and Comparative Example are prepared. Was prepared. The amount of the conductive particles was 1.5% by volume based on the total volume of the circuit connecting material. Each of the obtained circuit connecting materials is applied onto a fluororesin film (base material) having a thickness of 80 μm using a coating apparatus, and the coating film is dried with hot air at 70 ° C. for 10 minutes, whereby a fluororesin as a base material is obtained. An adhesive sheet having an adhesive layer (film-like circuit connecting material) having a thickness of 16 μm provided on the film and the substrate was obtained.

3. Measurement of connection resistance and adhesive strength Flexible circuit board (FPC) having a polyimide film (Tg 350 ° C.) and 80 copper circuits (line width 25 μm, pitch 50 μm, thickness 8 μm) arranged in a certain direction on the polyimide film And a circuit member (surface resistance 20Ω / □) having a circuit made of a thin layer of indium oxide (ITO) having a thickness of 0.2 μm formed on the glass substrate (thickness 1.1 mm), and these The film-like circuit connecting materials of each Example and Comparative Example were interposed between the two. Next, using a thermocompression bonding apparatus (heating method: constant heat type, manufactured by Toray Engineering Co., Ltd.), FPC is bonded to a circuit member having a glass substrate over a width of 3 mm by heating and pressing at 140 ° C. and 4 MPa for 10 seconds. Thus, a circuit connection body was obtained.

  The resistance value between adjacent circuits of the obtained circuit connection body was measured with a multimeter immediately after bonding and after being held in a high-temperature and high-humidity bath at 85 ° C. and 85% RH for 240 hours (after the test). The resistance value was shown as an average of 37 resistances between adjacent circuits. The measurement results are shown in Table 2.

  Further, between the FPC and the circuit member having a 100 μm-thick PET film (Tg = 67 ° C.), PC film (Tg = 150 ° C.), PEN film (Tg = 113 ° C.), or glass substrate, The film-like circuit connecting materials of Examples and Comparative Examples were interposed. Next, using the same thermocompression bonding apparatus as described above, the FPC was bonded over a width of 1 mm by heating and pressurizing at 140 ° C. and 4 MPa for 10 seconds to prepare a connection body.

  The adhesive strength of the obtained connection body was measured by a 90-degree peeling method according to JIS-Z0237. As a measuring device for adhesion strength, “Tensilon UTM-4” (trade name) (peeling speed 50 mm / min, 25 ° C.) manufactured by Toyo Baldwin Co., Ltd. was used. The measurement results are shown in Table 2.

  The circuit connector produced using the film-like adhesive of each example has a good connection resistance of about 2.4Ω or less immediately after bonding and after the test under a heating temperature of 140 ° C. Even in the case of a thermoplastic resin substrate such as a PET film, a good adhesive strength of 640 N / m or more was exhibited.

  On the other hand, the circuit connection body produced using the film-like circuit connection material of the comparative example not containing the monofunctional radical polymerizable compound represented by the formula (1) or (2) exhibits good adhesive strength. However, the connection resistance showed a high value of 2.2Ω or more immediately after bonding.

  From the above results, according to the circuit connection material according to the present invention, connection of circuit members having an organic base material having low heat resistance such as polyethylene terephthalate (PET), polycarbonate (PC), polyethylene naphthalate (PEN), etc. It was confirmed that excellent adhesion strength can be obtained even when the test is performed with a stable performance (adhesion strength and connection resistance) even after a long-term reliability test under high temperature and high humidity. .

  According to the circuit connection material according to the present invention, not only a glass substrate but also an organic base material containing a thermoplastic resin having a glass transition temperature of 200 ° C. or less, excellent connection resistance and adhesive strength by curing at a low temperature. Can be obtained. Therefore, the circuit connection material according to the present invention is suitably used in connection between a semiconductor element and an FPC using an organic base material having low heat resistance such as PET, PC, PEN and the like.

  DESCRIPTION OF SYMBOLS 10 ... Film-like circuit connection material, 12 ... Base material, 14 ... Adhesive component, 16 ... Connection part, 17 ... Conductive particle, 20 ... First circuit member, 21 ... First circuit board, 21a ... First The main surface of the circuit board, 22 ... the first circuit electrode, 30 ... the second circuit member, 31 ... the second circuit board, 31a ... the main surface of the second circuit board, 32 ... the second circuit electrode, 200 ... circuit connections.

Claims (13)

(A) a thermoplastic resin;
(B) a bifunctional or higher functional radical polymerizable compound;
(C) a monofunctional radically polymerizable compound represented by the following general formula (1) or (2);
(D) a radical polymerization initiator;
Containing
The thermoplastic resin includes a first resin having a glass transition temperature of 60 ° C. or higher and a second resin having a glass transition temperature of −5 ° C. to 40 ° C., and the first resin and the second resin One or both of the resins are resins having a urethane bond and an ester bond ,
A first circuit member having a first circuit board and a first circuit electrode provided on the first circuit board; a second circuit board; and a second circuit board provided on the second circuit board. The first circuit member so that the first circuit electrode and the second circuit electrode are electrically connected by being interposed between and cured with a second circuit member having the circuit electrode; A circuit connection material used for bonding the second circuit member.

[In Formula (1), R ¹ is an aromatic hydrocarbon group that may have a substituent, an aliphatic hydrocarbon group that may have a substituent, or an oil that may have a substituent. A group consisting of a cyclic hydrocarbon group or a combination thereof, wherein R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a plurality of R ² and R ² in the same molecule; R ⁴ may be the same or different, and n represents an integer of 1 to 20. ]

[In Formula (2), R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a plurality of R ⁴ in the same molecule may be the same or different, and R ⁵ is The aromatic hydrocarbon group which may have a substituent is shown, n shows the integer of 1-20. ] The circuit connection material according to claim 1, further comprising (f) a vinyl compound having a phosphate group and different from the bifunctional or higher-functional radical polymerizable compound. (E) further contains conductive particles electrically, the circuit connecting material according to claim 1 or 2. The film-form circuit connection material which consists of a circuit connection material as described in any one of Claims 1-3 shape | molded in the film form. A circuit connection sheet comprising a substrate and the film-like circuit connection material according to claim 4 formed on the substrate. A first circuit member having a first circuit board and a first circuit electrode provided on the first circuit board;
A second circuit member having a second circuit board and a second circuit electrode provided on the second circuit board;
The first circuit member is interposed between the first circuit member and the second circuit member so that the first circuit electrode and the second circuit electrode are electrically connected to each other. A connecting portion for bonding the second circuit member;
The circuit connection body in which the connection part is a cured product of the circuit connection material according to any one of claims 1 to 3 . The circuit connector according to claim 6 , wherein at least one of the first circuit board and the second circuit board is an organic base material including a thermoplastic resin having a glass transition temperature of 200 ° C. or lower. The circuit connector according to claim 7 , wherein the thermoplastic resin having a glass transition temperature of 200 ° C. or less includes at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. At least one of the first circuit board and the second circuit board is an organic base material including a thermoplastic resin including at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. Item 7. The circuit connector according to Item 6 . A first circuit member having a first circuit board and a first circuit electrode provided on the first circuit board; a second circuit board; and a second circuit board provided on the second circuit board. The first circuit electrode and the second circuit electrode are cured by curing the circuit connecting material according to any one of claims 1 to 4 interposed between the second circuit member having the circuit electrode. And connecting the first circuit member and the second circuit member so that they are electrically connected to each other. The circuit member connection method according to claim 10 , wherein at least one of the first circuit board and the second circuit board is an organic base material including a thermoplastic resin having a glass transition temperature of 200 ° C. or less. . The circuit member connection method according to claim 11 , wherein the thermoplastic resin having a glass transition temperature of 200 ° C. or lower includes at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. At least one of the first circuit board and the second circuit board is an organic base material including a thermoplastic resin including at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. Item 11. A method for connecting circuit members according to Item 10 .

Images