JP6114557B2 - Conductive material and connection structure manufacturing method - Google Patents

Description

  The present invention relates to a conductive material that can be suitably used to electrically connect electrodes of various connection target members such as a substrate for an organic electroluminescence display element. The present invention also relates to a connection structure using the conductive material and a method for manufacturing the connection structure.

  An organic electroluminescence (hereinafter sometimes referred to as organic EL) display element has a stacked structure in which an organic light emitting material layer is sandwiched between a pair of electrodes corresponding to each other. When electrons are injected from one electrode into the organic light emitting material layer and holes are injected from the other electrode, electrons and holes are combined in the organic light emitting material layer to emit light. Since the organic EL display element emits light by itself, the organic EL display element has better visibility than a liquid crystal display element that requires a backlight, can be reduced in thickness, and can be driven with a low DC voltage. Has the advantage.

  As an example of the organic EL display element, in FIG. 9A of Patent Document 1 below, an organic EL element in which an electrode of an organic EL substrate including the organic EL element and an electrode of a sealing substrate are bonded by an adhesive portion. Is disclosed. In the Example of the said patent document 1, in order to form the said adhesion part, using thermosetting epoxy adhesive containing an anisotropic conductive particle is described.

JP 2009-117214 A

  In the thermosetting epoxy adhesive containing anisotropic conductive particles as described in Patent Document 1, curing is performed when the electrode of the organic EL substrate and the electrode of the sealing substrate are bonded by an adhesive portion. In addition, the viscosity of the adhesive becomes too low, and the adhesive may flow excessively. For this reason, it may not be possible to dispose a conductive material in a specific region, and further, adjacent electrodes that should not be connected may be electrically connected via a plurality of conductive particles.

  An object of the present invention is to use a conductive material capable of obtaining a connection structure with few voids by accurately arranging a cured layer and conductive particles formed of a conductive material in a specific region, and using the conductive material. It is to provide a connection structure and a method for manufacturing the connection structure.

  A limited object of the present invention is to provide a conductive material capable of improving the moisture resistance of a cured product, a connection structure using the conductive material, and a method of manufacturing the connection structure.

  According to a wide aspect of the present invention, a conductive material that is used by being cured by heating to a temperature of 120 ° C. or lower without heating to a temperature exceeding 120 ° C., comprising a curable component, organic particles, and inorganic A conductive material is provided that includes a filler and conductive particles.

  The conductive material according to the present invention is suitably used for electrical connection of electrodes in an organic electroluminescence display element.

  The conductive material which concerns on this invention is used suitably for the electrical connection of the electrode of an organic electroluminescent board | substrate provided with an organic electroluminescent element, and the electrode of a sealing substrate.

  The organic particles are preferably core-shell particles having a core and a shell disposed on the surface of the core. It is preferable that the core is formed of a first (meth) acrylic resin and the shell is formed of a second (meth) acrylic resin.

  The glass transition temperature of the first (meth) acrylic resin is preferably higher than the glass transition temperature of the second (meth) acrylic resin.

  The average particle diameter of the inorganic filler is preferably 0.1 μm or more and 1 μm or less.

  In a specific aspect of the conductive material according to the present invention, the curable component includes a curable compound and a cation generator.

  In a specific aspect of the conductive material according to the present invention, the curable compound includes an epoxy compound that is liquid at 23 ° C. and an epoxy compound that is solid at 23 ° C.

  On the specific situation with the electrically conductive material which concerns on this invention, the said electroconductive particle has a base material particle and the electroconductive layer arrange | positioned on the surface of the said base material particle.

  According to a wide aspect of the present invention, the apparatus includes a first connection target member, a second connection target member, and a connection portion that electrically connects the first and second connection target members, There is provided a connection structure in which the connection portion is formed by heating and curing the above-described conductive material to a temperature of 120 ° C. or lower without heating to 120 ° C. or higher.

  In a specific aspect of the connection structure according to the present invention, the first connection target member has a first electrode on the surface, and the second connection target member has a second electrode on the surface, The first electrode and the second electrode are electrically connected by the conductive particles.

  On the specific situation with the connection structure which concerns on this invention, the said 1st, 2nd connection object member is a board | substrate for organic electroluminescent display elements.

  On the specific situation with the connection structure which concerns on this invention, a said 1st connection object member and a said 2nd connection object member are an organic electroluminescent board | substrate and sealing substrate provided with an organic electroluminescent element.

  According to a wide aspect of the present invention, there is provided a method for manufacturing the connection structure described above, the step of disposing a conductive material layer with the conductive material on the surface of the first connection target member; The step of disposing the second connection target member on the surface opposite to the first connection target member side, and heating to a temperature of 120 ° C. or less without heating to a temperature exceeding 120 ° C., And a step of curing a conductive material layer to form a connection portion that electrically connects the first and second connection target members.

  Since the conductive material according to the present invention contains a curable component, organic particles, inorganic filler, and conductive particles, it is cured by heating to a temperature of 120 ° C. or lower without heating to a temperature exceeding 120 ° C. When this is done, the conductive material disposed on the connection target member becomes difficult to flow greatly, and the cured product layer and conductive particles formed of the conductive material can be accurately disposed in a specific region. . Furthermore, it can suppress that the adjacent electrodes which should not be connected are electrically connected through several electroconductive particle. By this, the conduction | electrical_connection reliability of the connection structure obtained can be improved. Furthermore, the hardened | cured material of an electrically-conductive material becomes difficult to wet and spread the surface of a connection object member excessively, and it can make it difficult to produce a void in the connection structure obtained.

FIG. 1 is a front sectional view schematically showing a connection structure using a conductive material according to an embodiment of the present invention. 2A to 2C are front cross-sectional views for explaining each step of obtaining a connection structure using a conductive material according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing an example of conductive particles.

  Hereinafter, the present invention will be described in detail.

  The conductive material according to the present invention is used by being cured by heating to a temperature of 120 ° C. or lower without heating to a temperature exceeding 120 ° C. The conductive material according to the present invention includes a curable component, organic particles, an inorganic filler, and conductive particles.

  When the conductive material according to the present invention has the above-described composition, it is not heated to a temperature exceeding 120 ° C., but is heated to a temperature of 120 ° C. or lower and cured by a connection portion formed of the conductive material. Contamination can be suppressed. Specifically, for example, when the conductive material according to the present invention is used to electrically connect the electrodes of an organic electroluminescence (organic EL) display element, the viscosity of the conductive material is reduced during the curing of the conductive material. Since it does not become too low, the said connection part can be arrange | positioned in a predetermined position. Furthermore, the hardened | cured material of an electrically-conductive material becomes difficult to wet and spread the surface of a connection object member excessively, and it can make it difficult to produce a void in the connection structure obtained. For this reason, the conduction | electrical_connection reliability of the connection structure in an organic EL display element can be improved, and it can make it hard to produce the malfunctioning of an organic EL display element.

  Furthermore, the moisture resistance of hardened | cured material becomes high because the electrically-conductive material which concerns on this invention has the composition mentioned above.

  As a method of curing the conductive material according to the present invention, a method of heating the conductive material, a method of heating the conductive material after irradiating the conductive material, and a method of heating the conductive material and then irradiating the conductive material with light. The method of doing is mentioned. In addition, when the photocuring speed and the thermosetting speed are different, light irradiation and heating may be performed simultaneously. Especially, the method of heating a conductive material after irradiating light to a conductive material is preferable. By the combined use of photocuring and heat curing, the conductive material can be cured in a short time. When the conductive material according to the present invention is cured, at least heating is performed. That is, the conductive material according to the present invention is used after being thermally cured.

  The conductive material includes a curing agent as the curable component. The conductive material preferably contains a cation generator as the curing agent. The curable component preferably contains a curable compound and a cation generator. The present inventors have found that the use of a cation generator can effectively improve conduction reliability as compared with the case where a thermosetting agent other than the cation generator (such as an imidazole compound) is used.

  The curable compound may be a curable compound (thermosetting compound or light and thermosetting compound) curable by heating, and is curable by irradiation with light (photocurable compound, Or light and thermosetting compounds). The curable compound is preferably a curable compound (thermosetting compound or light and thermosetting compound) that can be cured by heating.

  The conductive material is a conductive material curable by heating, and may include a curable compound (thermosetting compound or light and thermosetting compound) curable by heating as the curable compound. The curable compound curable by heating may be a curable compound (thermosetting compound) that is not cured by light irradiation, and is curable by both light irradiation and heating (light and light). Thermosetting compound).

  The conductive material is a conductive material that can be cured by both light irradiation and heating, and the curable compound is a curable compound that can be cured by light irradiation (a photocurable compound, or light and heat). It is preferable to further contain a curable compound). In this case, the conductive material can be semi-cured (B-staged) by light irradiation to reduce the fluidity of the conductive material, and then the conductive material can be cured by heating. The curable compound that can be cured by light irradiation may be a curable compound (photocurable compound) that is not cured by heating, and is a curable compound that can be cured by both light irradiation and heating (light and light). Thermosetting compound).

  The cation generator contained in the conductive material according to the present invention may be a cation generator (thermal cation generator or light and thermal cation generator) that generates cations by heating, and is irradiated with light. It may be a photocation generator that generates cations (photocation generator, or light and thermal cation generator). The cation generator is preferably a cation generator that generates cations by heating (thermal cation generator or light and thermal cation generator). The conductive material is preferably thermoset by the action of the cation generator. The conductive material may be photocured by the action of the cation generator, and the conductive material may be thermoset by the action of the cation generator.

  The conductive material according to the present invention may contain a photocuring initiator. The conductive material according to the present invention preferably contains a photoradical generator as the photocuring initiator.

  The conductive material preferably contains a thermosetting compound as the curable compound, and further contains a photocurable compound or light and a thermosetting compound. The conductive material preferably contains a thermosetting compound and a photocurable compound as the curable compound.

  Hereinafter, first, details of each component suitably used for the conductive material according to the present invention will be described.

(Curable compound)
The curable compound contained in the conductive material is not particularly limited. A conventionally known curable compound can be used as the curable compound. As for the said sclerosing | hardenable compound, only 1 type may be used and 2 or more types may be used together.

  The curable compound preferably contains a curable compound having an epoxy group. The curable compound having an epoxy group is an epoxy compound. As for the said curable compound which has an epoxy group, only 1 type may be used and 2 or more types may be used together.

  The curable compound having an epoxy group preferably has an aromatic ring. Examples of the aromatic ring include a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, tetracene ring, chrysene ring, triphenylene ring, tetraphen ring, pyrene ring, pentacene ring, picene ring, and perylene ring. Among these, the aromatic ring is preferably a benzene ring, a naphthalene ring or an anthracene ring, more preferably a benzene ring or a naphthalene ring, and still more preferably a naphthalene ring. Since the naphthalene ring has a planar structure, it can be cured more rapidly.

  From the viewpoint of enhancing the curability of the conductive material, the content of the curable compound having an epoxy group is preferably 10% by weight or more, more preferably 20% by weight or more, in the total 100% by weight of the curable compound. , 100% by weight or less. The total amount of the curable compound may be the curable compound having the epoxy group. When using together the curable compound which has the said epoxy group, and the other curable compound different from the curable compound which has this epoxy group, hardening which has the said epoxy group in the whole 100 weight% of the said curable compound The content of the functional compound is preferably 99% by weight or less, more preferably 95% by weight or less, still more preferably 90% by weight or less, and particularly preferably 80% by weight or less.

  The curable compound preferably contains an epoxy compound that is liquid at 23 ° C, preferably contains an epoxy compound that is solid at 23 ° C, and both an epoxy compound that is liquid at 23 ° C and an epoxy compound that is solid at 23 ° C It is preferable to contain.

  Examples of the epoxy compound include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol O type epoxy compounds, bisphenol S type epoxy compounds, and hydrides of these epoxy compounds. Among them, the curability of the conductive material is further increased, the glass transition temperature of the cured product is further increased and the moisture resistance is further decreased, and further, the cured product is further excellent in heat resistance, UV resistance and adhesiveness. Since it is obtained, the epoxy compound which is liquid at 23 ° C. is preferably a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, a hydrogenated bisphenol A type epoxy compound or a hydrogenated bisphenol F type epoxy compound.

  The weight average molecular weight of the epoxy compound that is liquid at 23 ° C. is preferably 150 or more, more preferably 200 or more, preferably 1200 or less, more preferably 1000 or less. When the weight average molecular weight is not less than the above lower limit, the glass transition temperature of the cured product is further increased, and the moisture resistance of the cured product is further enhanced. When the weight average molecular weight is not more than the above upper limit, the coating property and curability of the conductive material are further improved.

  The content of the epoxy compound which is liquid at 23 ° C. is preferably 30% by weight or more, more preferably 40% by weight or more, preferably 90% by weight or less, more preferably 80% by weight in the total 100% by weight of the curable compound. % Or less. When the content of the liquid epoxy compound is not less than the above lower limit, the coating property of the conductive material is further enhanced. When the content of the liquid epoxy compound is not more than the above upper limit, the coating property of the conductive material is further enhanced, and the moisture resistance of the cured product is further enhanced.

  Examples of the epoxy compound that is solid at 23 ° C. include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol O type epoxy compounds, bisphenol S type epoxy compounds, and hydrides of these epoxy compounds. Among them, since the curability of the conductive material is further increased, the glass transition temperature of the cured product is further increased and the moisture resistance is further decreased, and further, the heat resistance, UV resistance and adhesiveness are excellent. The epoxy compound that is liquid at ° C is preferably a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, a hydrogenated bisphenol A type epoxy compound, or a hydrogenated bisphenol F type epoxy compound.

  The weight average molecular weight of the epoxy compound solid at 23 ° C. is preferably 200 or more, more preferably 250 or more, preferably 5000 or less, more preferably 4500 or less. When the weight average molecular weight is not less than the above lower limit, the moisture resistance and adhesiveness of the cured product are further enhanced. When the weight average molecular weight is not more than the above upper limit, the curability of the conductive material becomes even better, the softening point of the conductive material becomes appropriate, and the compatibility between the liquid epoxy compound and the solid epoxy compound Becomes even higher.

  The weight average molecular weight is a value in terms of polystyrene measured by gel permeation chromatography (GPC). Examples of the column used for the measurement of the weight average molecular weight include “Shodex LF-804” manufactured by Showa Denko KK.

  The content of the epoxy compound that is solid at 23 ° C. is preferably 10% by weight or more, more preferably 15% by weight or more, preferably 40% by weight or less, more preferably 35% by weight in the total 100% by weight of the curable compound. % Or less. When the content of the solid epoxy compound is not less than the above lower limit, the moisture resistance of the cured product is further enhanced. When the content of the solid epoxy compound is not more than the above upper limit, the coating property of the conductive material is further enhanced.

  Moreover, it is preferable that the said sclerosing | hardenable compound contains an alicyclic epoxy compound. The alicyclic epoxy compound is preferably the liquid epoxy compound, preferably the solid epoxy compound, and more preferably both the liquid epoxy compound and the solid epoxy compound. . The weight average molecular weight of the alicyclic epoxy compound is preferably 100 or more, more preferably 150 or more, preferably 1000 or less, more preferably 800 or less. By using an alicyclic epoxy compound or using an alicyclic epoxy compound having a weight average molecular weight of not less than the above lower limit and not more than the above upper limit, the curability of the conductive material is further improved. When the weight average molecular weight of the alicyclic epoxy compound is not less than the above lower limit, the volatility of the alicyclic epoxy compound is lowered, and the problem of gas generation is less likely to occur. When the weight average molecular weight of the alicyclic epoxy compound is not more than the above upper limit, the viscosity of the conductive material becomes appropriate, and the coating property of the conductive material is further enhanced.

  Examples of commercially available alicyclic epoxy resins include Celoxide 2021P, Celoxide 2081P, Celoxide 2000, Celoxide 2083, Celoxide 2085, and Celoxide 3000 (all manufactured by Daicel). Of these, Celoxide 2021P is preferred because of its low viscosity and excellent curability.

  The content of the alicyclic epoxy compound is preferably 5% by weight or more, preferably 30% by weight or less, more preferably 25% by weight or less in the total 100% by weight of the curable compound. When the content of the alicyclic epoxy compound is not less than the above lower limit, the curability of the conductive material is further enhanced. When the content of the alicyclic epoxy compound is not more than the above upper limit, the coating property of the conductive material is further enhanced.

  Moreover, it is preferable that the said sclerosing | hardenable compound contains a phenol novolak-type epoxy compound.

  The curable compound may further contain another curable compound different from the curable compound having an epoxy group. Examples of the other curable compounds include curable compounds having an unsaturated double bond, phenol curable compounds, amino curable compounds, unsaturated polyester curable compounds, polyurethane curable compounds, silicone curable compounds, and polyimide curable compounds. Compounds and the like. As for said other curable compound, only 1 type may be used and 2 or more types may be used together.

  From the viewpoint of easily controlling the curing of the conductive material or further improving the conduction reliability between the electrodes, the curable compound preferably contains a curable compound having an unsaturated double bond. . From the viewpoint of easily controlling the curing of the conductive material and further enhancing the conduction reliability between the electrodes, the curable compound having an unsaturated double bond is a curable compound having a (meth) acryloyl group. A compound is preferred. By using the curable compound having the (meth) acryloyl group, the curing rate is suitable for the entire B-staged conductive material (including the part directly irradiated with light and the part not directly irradiated with light). And the reliability of conduction between the electrodes is further enhanced.

  From the viewpoint of easily controlling the curing rate of the B-staged conductive material layer and further enhancing the conduction reliability between the electrodes, the curable compound having the (meth) acryloyl group includes a (meth) acryloyl group. It is preferable to have one or two.

  The curable compound having the (meth) acryloyl group has no epoxy group and has a (meth) acryloyl group, and has a epoxy group and a curable compound having a (meth) acryloyl group. Compounds.

  As the curable compound having the (meth) acryloyl group, an ester compound obtained by reacting a (meth) acrylic acid and a compound having a hydroxyl group, an epoxy obtained by reacting (meth) acrylic acid and an epoxy compound ( A (meth) acrylate, a urethane (meth) acrylate obtained by reacting a (meth) acrylic acid derivative having a hydroxyl group with an isocyanate, or the like is preferably used. The “(meth) acryloyl group” refers to an acryloyl group and a methacryloyl group. The “(meth) acryl” refers to acryl and methacryl. The “(meth) acrylate” refers to acrylate and methacrylate.

  The curable compound preferably contains an epoxy (meth) acrylate. The said epoxy (meth) acrylate is a compound which made all the epoxy groups in an epoxy compound react with (meth) acrylic acid.

  Commercially available epoxy (meth) acrylates include EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3703, EBECRYL3703, EBECRYL3703, EBECRYL3703, -1020, EA-5323, EA-5520, EA-CHD and EMA-1020 (all manufactured by Shin-Nakamura Chemical Co., Ltd.), epoxy ester M-600A, epoxy ester 40EM, epoxy ester 70PA, epoxy ester 200PA, epoxy ester 80MFA , Epoxy ester 3 02M, Epoxy ester 3002A, Epoxy ester 1600A, Epoxy ester 3000M, Epoxy ester 3000A, Epoxy ester 200EA and Epoxy ester 400EA (all manufactured by Kyoeisha Chemical Co., Ltd.), and Denacol acrylate DA-141, Denacol acrylate DA-314 and Dena Examples include coal acrylate DA-911 (all manufactured by Nagase ChemteX Corporation).

  The ester compound obtained by making the said (meth) acrylic acid and the compound which has a hydroxyl group react is not specifically limited. As the ester compound, any of a monofunctional ester compound, a bifunctional ester compound, and a trifunctional or higher functional ester compound can be used.

  The curable compound having an epoxy group and a (meth) acryloyl group is obtained by converting a part of the epoxy group of the compound having two or more epoxy groups into a (meth) acryloyl group. A compound is preferred. This curable compound is a partially (meth) acrylated epoxy compound.

  The curable compound preferably contains a reaction product of a compound having two or more epoxy groups and (meth) acrylic acid. This reaction product is obtained by reacting a compound having two or more epoxy groups with (meth) acrylic acid in the presence of a catalyst according to a conventional method. It is preferable that 20% or more of the epoxy group is converted (conversion rate) to a (meth) acryloyl group. The conversion is more preferably 30% or more, preferably 80% or less, more preferably 70% or less. Most preferably, 40% or more and 60% or less of the epoxy groups are converted to (meth) acryloyl groups.

  Examples of the partial (meth) acrylated epoxy compound include a bisphenol type epoxy part (meth) acrylate, a cresol novolac type epoxy part (meth) acrylate, a carboxylic anhydride modified epoxy part (meth) acrylate, and a phenol novolac type epoxy part ( And (meth) acrylate.

  As the curable compound, a modified phenoxy resin in which a part of the epoxy group of the phenoxy resin having two or more epoxy groups is converted to a (meth) acryloyl group may be used. That is, a modified phenoxy resin having an epoxy group and a (meth) acryloyl group may be used.

  The curable compound may be a crosslinkable compound or a non-crosslinkable compound.

  Specific examples of the crosslinkable compound include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, (poly ) Ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, glycerol methacrylate acrylate, pentaerythritol tri (meth) acrylate, tri Examples include methylolpropane trimethacrylate, allyl (meth) acrylate, vinyl (meth) acrylate, divinylbenzene, polyester (meth) acrylate, and urethane (meth) acrylate.

  Specific examples of the non-crosslinkable compound include ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) ) Acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, decyl (Meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, and the like.

  When a thermosetting compound and a photocurable compound are used in combination, the blending ratio of the photocurable compound and the thermosetting compound is appropriately adjusted according to the type of the photocurable compound and the thermosetting compound. The The conductive material preferably contains a photocurable compound and a thermosetting compound in a weight ratio of 1:99 to 90:10, more preferably 5:95 to 60:40, and more preferably 10:90. More preferably, it is included at -40: 60.

(Curing agent)
The conductive material includes a curing agent. The curing agent includes a thermosetting agent and may further include a photocuring initiator. The curing agent includes a cation generator. Conventionally known cation generators can be used as the cation generator. In the present invention, the cation generator is preferably used as a thermal cation generator for at least thermally curing the conductive material, not as a photo cation generator for only photocuring the conductive material. Furthermore, in the present invention, the cation generator is more preferably used as a thermal cation generator for thermosetting the conductive material, not as a photo cation generator for photocuring the conductive material. As for the said cation generator, only 1 type may be used and 2 or more types may be used together.

  As the cation generator, iodonium salts and sulfonium salts are preferably used. For example, commercially available products of the cation generator include San-Aid SI-45L, SI-60L, SI-80L, SI-100L, SI-110L, SI-150L manufactured by Sanshin Chemical Co., Ltd., and Adekatop manufactured by ADEKA. MER SP-150, SP-170 and the like.

Preferred anion moieties of the cation generator include PF ₆ , BF ₄ , and B (C ₆ F ₅ ) ₄ .

  Other specific examples of the cation generator include 2-butenyldimethylsulfonium tetrakis (pentafluorophenyl) borate, 2-butenyldimethylsulfonium tetrafluoroborate, 2-butenyldimethylsulfonium. Hexafluorophosphate, 2-butenyltetramethylenesulfonium tetrakis (pentafluorophenyl) borate, 2-butenyltetramethylenesulfonium tetrafluoroborate, 2-butenyltetramethylenesulfonium hexafluorophosphate, 3-methyl 2-butenyldimethylsulfonium tetrakis (pentafluorophenyl) borate, 3-methyl-2-butenyldimethylsulfonium tetrafluoroborate, 3-methyl-2-butenyldimethylsulfo Um hexafluorophosphate, 3-methyl-2-butenyltetramethylenesulfonium tetrakis (pentafluorophenyl) borate, 3-methyl-2-butenyltetramethylenesulfonium tetrafluoroborate, 3-methyl-2-but Tenenyltetramethylenesulfonium hexafluorophosphate, 4-hydroxyphenylcinnamylmethylsulfonium tetrakis (pentafluorophenyl) borate, 4-hydroxyphenylcinnamylmethylsulfonium tetrafluoroborate, 4-hydroxyphenylcinnamylmethylsulfate Phonium hexafluorophosphate, α-naphthylmethyltetramethylenesulfonium tetrakis (pentafluorophenyl) borate, α-naphthylmethyltetramethylenes Phonium tetrafluoroborate, α-naphthylmethyltetramethylenesulfonium hexafluorophosphate, cinnamyldimethylsulfonium tetrakis (pentafluorophenyl) borate, cinnamyldimethylsulfonium tetrafluoroborate, cinnamyldimethylsulfonium hexa Fluorophosphate, cinnamyltetramethylenesulfonium tetrakis (pentafluorophenyl) borate, cinnamyltetramethylenesulfonium tetrafluoroborate, cinnamyltetramethylenesulfonium hexafluorophosphate, biphenylmethyldimethylsulfonium tetrakis (pentafluoro) Phenyl) borate, biphenylmethyldimethylsulfonium tetrafluoroborate, biphe Nylmethyldimethylsulfonium hexafluorophosphate, biphenylmethyltetramethylenesulfonium tetrakis (pentafluorophenyl) borate, biphenylmethyltetramethylenesulfonium tetrafluoroborate, biphenylmethyltetramethylenesulfonium hexafluorophosphate, phenylmethyldimethyl Sulfonium tetrakis (pentafluorophenyl) borate, phenylmethyldimethylsulfonium tetrafluoroborate, phenylmethyldimethylsulfonium hexafluorophosphate, phenylmethyltetramethylenesulfonium tetrakis (pentafluorophenyl) borate, phenylmethyltetramethylene Sulfonium tetrafluoroborate, phenyl methyl ester Ramethylene sulfonium hexafluorophosphate, fluorenylmethyldimethylsulfonium tetrakis (pentafluorophenyl) borate, fluorenylmethyldimethylsulfonium tetrafluoroborate, fluorenylmethyldimethylsulfonium hexafluorophosphate, full Examples include oleenylmethyltetramethylenesulfonium tetrakis (pentafluorophenyl) borate, fluorenylmethyltetramethylenesulfonium tetrafluoroborate, and fluorenylmethyltetramethylenesulfonium hexafluorophosphate.

  It is preferable that the cation generator release inorganic acid ions by heating or release organic acid ions containing boron atoms by heating. The cation generator is preferably a component that releases inorganic acid ions by heating, and is also preferably a component that releases organic acid ions containing boron atoms by heating.

The cation generator that releases inorganic acid ions by heating is preferably a compound having SbF ⁶⁻ or PF ⁶⁻ as the anion moiety. The cation generator is preferably a compound having SbF ⁶⁻ as the anion moiety, and is preferably a compound having PF ⁶⁻ as the anion moiety.

Anionic portion of the cation generator is _{B (C 6 X 5) 4} - is preferably represented by. The cation generator that releases an organic acid ion containing a boron atom is preferably a compound having an anion moiety represented by the following formula (1).

  In the above formula (1), X represents a halogen atom. X in the formula (1) is preferably a chlorine atom, a bromine atom or a fluorine atom, and more preferably a fluorine atom.

It is preferable that the anion portion of the cation generator is represented by B (C ₆ F ₅ ) ₄ ^— . The cation generator that releases an organic acid ion containing a boron atom is more preferably a compound having an anion moiety represented by the following formula (1A).

  The kind of the cation generator may be an ionic photoacid generating type or a nonionic photoacid generating type. The cation generator is preferably an antimony complex, a salt having phosphorus hexafluoride ion, or a salt represented by the following formula (2).

  In the above formula (2), n represents an integer of 1 to 12, m represents an integer of 1 to 5, and Rf is a fluoroalkyl group in which all or part of the hydrogen atoms of the alkyl group are substituted with fluorine atoms. Represents.

  The antimony complex is not particularly limited, but is preferably a sulfonium salt. Examples of the sulfonium salt that is the antimony complex include tetraphenyl (diphenyl sulfide-4,4′-diyl) bissulfonium di (antimony hexafluoride), tetra (4-methoxyphenyl) [diphenyl sulfide-4,4 ′. -Diyl] bissulfonium di (antimony hexafluoride), diphenyl (4-phenylthiophenyl) sulfonium hexamonium fluoride, and di (4-methoxyphenyl) [4-phenylthiophenyl] sulfonium hexamonium hexafluoride Etc.

  As a commercial item of the said antimony complex, Adeka optomer SP170 (made by ADEKA) etc. are mentioned, for example.

  As a commercial item of the salt which has the said hexafluoride phosphorus ion, WPI-113 (made by Wako Pure Chemical Industries), CPI-100P (made by San Apro), etc. are mentioned, for example.

  The content of the cation generator is not particularly limited. The content of the cation generator is preferably 0.01 parts by weight or more, more preferably 0.05 parts by weight or more, still more preferably 5 parts by weight or more, particularly preferably 100 parts by weight of the curable compound. It is 10 parts by weight or more, preferably 40 parts by weight or less, more preferably 30 parts by weight or less, and still more preferably 20 parts by weight or less. When the content of the cation generator relative to the curable compound is not less than the above lower limit and not more than the above upper limit, the conductive material is sufficiently cured.

  The content of the cation generator is preferably 0.01 parts by weight or more, more preferably 0.05 parts by weight or more, and still more preferably 5 parts by weight with respect to 100 parts by weight of the curable compound curable by heating. Above, particularly preferably 10 parts by weight or more, preferably 40 parts by weight or less, more preferably 30 parts by weight or less, and still more preferably 20 parts by weight or less. When the content of the cation generator relative to the curable compound curable by heating is not less than the above lower limit and not more than the above upper limit, the conductive material is sufficiently thermally cured.

  From the viewpoint of further improving the connection reliability between electrodes and the connection reliability under high humidity such as an organic EL display element, the conductive material includes both the cation generator and the thermal radical generator. Is preferred. The thermal radical generator is not particularly limited. As the thermal radical generator, a conventionally known thermal radical generator can be used. As for the said thermal radical generator, only 1 type may be used and 2 or more types may be used together. Here, the “thermal radical generator” means a compound that generates radical species by heating.

  The thermal radical generator is not particularly limited, and examples thereof include azo compounds and peroxides. Examples of the peroxide include diacyl peroxide compounds, peroxyester compounds, hydroperoxide compounds, peroxydicarbonate compounds, peroxyketal compounds, dialkyl peroxide compounds, and ketone peroxide compounds.

  Other examples of the thermosetting agent include hydrazide compounds, imidazole compounds, acid anhydrides, dicyandiamides, guanidine compounds, modified aliphatic polyamines, addition products of amine compounds and epoxy compounds, and the like.

  The hydrazide compound is not particularly limited, and examples thereof include 1,3-bis [hydrazinocarbonoethyl-5-isopropylhydantoin].

  The imidazole compound is not particularly limited. For example, 1-cyanoethyl-2-phenylimidazole, N- [2- (2-methyl-1-imidazolyl) ethyl] urea, 2,4-diamino-6- [2 ′ -Methylimidazolyl- (1 ')]-ethyl-s-triazine, N, N'-bis (2-methyl-1-imidazolylethyl) urea, N, N'-(2-methyl-1-imidazolylethyl)- Examples include adipamide, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and 2-phenyl-4,5-dihydroxymethylimidazole.

  The acid anhydride is not particularly limited, and examples thereof include tetrahydrophthalic anhydride and ethylene glycol-bis (anhydro trimellitate).

  The content of the thermosetting agent is not particularly limited. The content of the thermosetting agent is preferably 0.01 parts by weight or more, more preferably 0.05 parts by weight or more, with respect to 100 parts by weight of the curable compound curable by heating in the curable compound. More preferably 5 parts by weight or more, particularly preferably 10 parts by weight or more, preferably 40 parts by weight or less, more preferably 30 parts by weight or less, still more preferably 20 parts by weight or less. When the content of the thermosetting agent is not less than the above lower limit and not more than the above upper limit, the conductive material can be sufficiently thermoset. When the thermosetting agent is only a thermal cation generator, the content of the thermosetting agent indicates the content of the cation generator, and the thermosetting agent is a cation generator and another thermosetting agent (heat In the case of including both a radical generator and the like, the total content of the cation generator and the other thermosetting agent is shown.

  When the curing agent contains a thermal radical generator, the content of the thermal radical generator is preferably 0.01 with respect to 100 parts by weight of the curable compound curable by heating in the curable compound. Part by weight or more, more preferably 0.05 part by weight or more, preferably 10 parts by weight or less, more preferably 5 parts by weight or less. When the content of the thermal radical generator is not less than the above lower limit and not more than the above upper limit, the conductive material can be sufficiently thermoset.

  The conductive material may contain a photocuring initiator as the curing agent. The photocuring initiator includes the above-described photocation generator (photocation generator or light and thermal cation generator). The photocuring initiator is not particularly limited. A conventionally known photocuring initiator can be used as the photocuring initiator. From the viewpoint of further improving the connection reliability between the electrodes and the connection reliability of the organic EL display element or the like, the conductive material preferably contains a photo radical generator. As for the said photocuring initiator, only 1 type may be used and 2 or more types may be used together.

  The photocuring initiator other than the cation generator is not particularly limited, and is not limited to acetophenone photocuring initiator (acetophenone photoradical generator), benzophenone photocuring initiator (benzophenone photoradical generator), thioxanthone, ketal light. Examples thereof include a curing initiator (ketal photo radical generator), halogenated ketone, acyl phosphinoxide, and acyl phosphonate.

  The content of the photocuring initiator is not particularly limited. The content of the photocuring initiator is preferably 0.1 parts by weight or more, more preferably 0.2 parts by weight with respect to 100 parts by weight of the curable compound that can be cured by light irradiation in the curable compound. Part or more, preferably 2 parts by weight or less, more preferably 1 part by weight or less. When the content of the photocuring initiator is not less than the above lower limit and not more than the above upper limit, the conductive material can be appropriately photocured. By irradiating the conductive material with light and forming a B stage, the flow of the conductive material can be suppressed. When the photocuring initiator is only a cation generator, the content of the photocuring initiator indicates the content of the cation generating agent, and the photocuring initiator is a cation generator and another photocuring initiator. When both are included, the total content of the cation generator and the other photocuring initiator is shown.

(Organic particles)
The organic particles contained in the conductive material act as a gelling agent. The organic particles swell in the conductive material at room temperature and moderately improve the viscosity of the conductive material. Furthermore, the organic particles have an effect of suppressing a decrease in viscosity during curing of the conductive material. In addition, by using the organic particles in combination with an inorganic filler, voids are less likely to occur in the cured product even when the substrates are bonded together under a reduced pressure atmosphere. As for the said organic particle, only 1 type may be used and 2 or more types may be used together.

  The organic particles are more preferably core-shell particles having a core and a shell disposed on the surface of the core. The core is preferably formed of a first (meth) acrylic resin. The (meth) acrylic resin is a general term for resins mainly composed of (meth) acrylic acid ester, and the (meth) acrylic resin includes acrylic rubber and the like. The shell is preferably formed of a second acrylic resin. The glass transition temperature of the second (meth) acrylic resin is preferably higher than the glass transition temperature of the first (meth) acrylic resin.

  Examples of commercially available organic particles include “Metablene W-5500, W-450A” manufactured by Mitsubishi Rayon Co., “F-351” manufactured by Gantz Kasei.

  The average particle diameter of the organic particles is preferably 0.1 μm or more, more preferably 0.2 μm or more, preferably 1 μm or less, more preferably 0.9 μm or less. The average particle size of the organic particles is a volume average particle size. The average particle size can be measured using a laser diffraction / scattering particle size distribution measuring device or the like.

  The content of the organic particles is not particularly limited. The content of the organic particles is preferably 1 part by weight or more, more preferably 5 parts by weight or more, preferably 30 parts by weight or less, more preferably 20 parts by weight or less with respect to 100 parts by weight of the curable compound. When the content of the organic particles is not less than the above lower limit, the viscosity of the conductive material becomes appropriate, and voids are hardly generated in the cured product. When the content of the organic particles is not more than the above upper limit, the coating property of the conductive material is further enhanced.

(Inorganic filler)
The inorganic filler contained in the conductive material has an effect of suppressing a decrease in viscosity during curing of the conductive material and further improving the moisture resistance of the cured product. As for the said inorganic filler, only 1 type may be used and 2 or more types may be used together.

  The average particle diameter of the inorganic filler is preferably 0.1 μm or more, more preferably 0.2 μm or more, preferably 1 μm or less, more preferably 0.9 μm or less. The inorganic filler whose average particle diameter is not less than the above lower limit and not more than the above upper limit further improves the moisture resistance of the cured product. When the average particle diameter of the inorganic filler is not more than the above upper limit, voids are further hardly generated in the cured product. In addition, the average particle diameter of the said inorganic filler is a volume average particle diameter. The average particle size can be measured using a laser diffraction / scattering particle size distribution measuring device or the like.

  Examples of the inorganic filler include talc, asbestos, silica, smectite, bentonite, calcium carbonate, magnesium carbonate, alumina, montmorillonite, diatomaceous earth, magnesium oxide, titanium oxide, magnesium hydroxide, aluminum hydroxide, glass beads, barium sulfate, gypsum, Examples thereof include calcium silicate and sericite activated clay. Among these, talc is preferable because blocking properties are improved and moisture resistance is improved.

  The inorganic filler is preferably plate-shaped. The average aspect ratio of the inorganic filler is 1 or more, preferably 2 or more, more preferably 3 or more, preferably 100 or less, more preferably 50 or less. When the average aspect ratio of the inorganic filler is not more than the above upper limit, the inorganic filler is less likely to be sandwiched between the electrode and the conductive particles, and as a result, the connection resistance between the electrodes is further reduced. Furthermore, as a result of being able to satisfactorily orient the inorganic filler even at a low pressure, the thickness of the connecting portion formed by the conductive particles becomes even more uniform. The average aspect ratio means an average value of the major axis of the inorganic filler / the minor axis of the inorganic filler.

  The content of the inorganic filler is not particularly limited. The content of the inorganic filler is preferably 1 part by weight or more, more preferably 2 parts by weight or more, preferably 30 parts by weight or less, more preferably 28 parts by weight or less with respect to 100 parts by weight of the curable compound. When the content of the inorganic filler is equal to or more than the lower limit, voids are further hardly generated in the cured product. When the content of the inorganic filler is not more than the above upper limit, the coating property of the conductive material is further enhanced.

(Conductive particles)
The said electroconductive particle should just have an electroconductive part on the electroconductive surface. The conductive part is preferably a conductive layer. As shown in a sectional view of an example of the conductive particles in FIG. 3, the conductive particles 11 may include a base particle 12 and a conductive layer 13 disposed on the surface of the base particle 12. . The conductive particles may be metal particles whose entirety is a conductive portion. Among these, from the viewpoint of reducing the cost and increasing the flexibility of the conductive particles to increase the conduction reliability between the electrodes, the base particles and the conductive material disposed on the surface of the base particles are used. Conductive particles having a layer are preferred.

  Examples of the substrate particles include resin particles, inorganic particles excluding metal particles, organic-inorganic hybrid particles, and metal particles. The substrate particles are preferably substrate particles excluding metal particles, and are preferably resin particles, inorganic particles excluding metal particles, or organic-inorganic hybrid particles.

  The substrate particles are preferably resin particles formed of a resin. When connecting between electrodes using electroconductive particle, after arrange | positioning electroconductive particle between electrodes, electroconductive particle is compressed by crimping | bonding. When the substrate particles are resin particles, the conductive particles are likely to be deformed during the pressure bonding, and the contact area between the conductive particles and the electrode is increased. For this reason, the conduction | electrical_connection reliability between electrodes becomes still higher.

  Examples of the resin for forming the resin particles include polyolefin resin, acrylic resin, phenol resin, melamine resin, benzoguanamine resin, urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polyethylene terephthalate, polysulfone, and polyphenylene. Examples thereof include oxide, polyacetal, polyimide, polyamideimide, polyetheretherketone, polyethersulfone, divinylbenzene polymer, and divinylbenzene copolymer. Examples of the divinylbenzene copolymer include divinylbenzene-styrene copolymer and divinylbenzene- (meth) acrylic acid ester copolymer. Since the hardness of the resin particles can be easily controlled within a suitable range, the resin for forming the resin particles is a polymer obtained by polymerizing one or more polymerizable monomers having an ethylenically unsaturated group. It is preferably a coalescence.

  Examples of the inorganic substance for forming the inorganic particles include silica and carbon black. Examples of the organic / inorganic hybrid particles include organic / inorganic hybrid particles formed of a crosslinked alkoxysilyl polymer and an acrylic resin.

  When the substrate particles are metal particles, examples of the metal for forming the metal particles include silver, copper, nickel, silicon, gold, and titanium.

  The metal for forming the conductive part is not particularly limited. Furthermore, in the case where the conductive particles are metal particles that are conductive parts as a whole, the metal for forming the metal particles is not particularly limited. Examples of the metal include gold, silver, palladium, copper, platinum, zinc, iron, tin, lead, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, thallium, germanium, cadmium, silicon, and these. And the like. Examples of the metal include tin-doped indium oxide (ITO) and solder. Especially, since the connection resistance between electrodes becomes still lower, an alloy containing tin, nickel, palladium, copper or gold is preferable, and nickel or palladium is preferable.

  The conductive layer may be formed of a single layer. The conductive layer may be formed of a plurality of layers. That is, the conductive layer may have a stacked structure of two or more layers. When the conductive layer is formed of a plurality of layers, the outermost layer is preferably a gold layer, a nickel layer, a palladium layer, a copper layer, or an alloy layer containing tin and silver, and is a gold layer. Is more preferable. When the outermost layer is these preferred conductive layers, the connection resistance between the electrodes is further reduced. Moreover, when the outermost layer is a gold layer, the corrosion resistance is further enhanced.

  The method for forming the conductive layer on the surface of the substrate particles is not particularly limited. As a method for forming the conductive layer, for example, a method by electroless plating, a method by electroplating, a method by physical vapor deposition, and a method of coating the surface of base particles with metal powder or a paste containing metal powder and a binder Etc. Especially, since formation of a conductive layer is simple, the method by electroless plating is preferable. Examples of the method by physical vapor deposition include methods such as vacuum vapor deposition, ion plating, and ion sputtering.

  The average particle diameter of the conductive particles is preferably 0.5 μm or more, more preferably 1 μm or more, preferably 500 μm or less, more preferably 100 μm or less, still more preferably 50 μm or less, and particularly preferably 20 μm or less. When the average particle diameter of the conductive particles is not less than the above lower limit and not more than the above upper limit, when the electrodes are connected using the conductive particles, the contact area between the conductive particles and the electrode becomes sufficiently large and the conductive Aggregated conductive particles are less likely to be formed when the layer is formed. Further, the distance between the electrodes connected via the conductive particles does not become too large, and the conductive layer is difficult to peel from the surface of the base material particles.

  The “average particle size” of the conductive particles indicates a number average particle size. The average particle diameter of the conductive particles can be obtained by observing 50 arbitrary conductive particles with an electron microscope or an optical microscope and calculating an average value.

  The thickness of the conductive layer is preferably 0.005 μm or more, more preferably 0.01 μm or more, preferably 10 μm or less, more preferably 1 μm or less, and still more preferably 0.3 μm or less. When the thickness of the conductive layer is not less than the above lower limit and not more than the above upper limit, sufficient conductivity is obtained, and the conductive particles do not become too hard, and the conductive particles are sufficiently deformed when connecting the electrodes. .

  When the conductive layer is formed of a plurality of layers, the thickness of the outermost conductive layer is preferably 0.001 μm or more, more preferably the thickness of the gold layer when the outermost layer is a gold layer. It is 0.01 μm or more, preferably 0.5 μm or less, more preferably 0.1 μm or less. When the thickness of the outermost conductive layer is not less than the above lower limit and not more than the above upper limit, the coating with the outermost conductive layer becomes uniform, corrosion resistance is sufficiently high, and the connection resistance between the electrodes is sufficiently high. Lower. Further, the thinner the gold layer when the outermost layer is a gold layer, the lower the cost.

  The thickness of the conductive layer can be measured, for example, by observing a cross section of the conductive particles or the conductive particles using a transmission electron microscope (TEM).

  From the viewpoint of increasing the contact area between the electrode and the conductive particle and further enhancing the conduction reliability between the electrodes, the conductive particle is composed of a resin particle and a conductive layer (on the surface of the resin particle ( First conductive layer).

  The surface of the conductive portion in the conductive particles may be insulated with an insulating material such as an insulating layer or insulating particles, a flux, or the like. It is preferable that the insulating material, the flux, and the like are removed from the connection portion by being softened and flowed by heat at the time of connection. Thereby, the short circuit between electrodes can be suppressed.

  The content of the conductive particles is not particularly limited. The content of the conductive particles in 100% by weight of the conductive material is preferably 0.1% by weight or more, more preferably 0.5% by weight or more, still more preferably 1% by weight or more, preferably 40% by weight or less. More preferably, it is 30 wt% or less, and further preferably 19 wt% or less. A conductive particle can be easily arrange | positioned between the upper and lower electrodes which should be connected as content of the said electroconductive particle is more than the said minimum and below the said upper limit. Furthermore, it becomes difficult to electrically connect adjacent electrodes that should not be connected via a plurality of conductive particles. That is, a short circuit between adjacent electrodes can be further prevented.

(Other ingredients)
The conductive material preferably contains a sensitizer. The sensitizer is preferably a benzophenone derivative represented by the following formula (11). The sensitizer has a role of further improving the polymerization initiation efficiency by the cation generator and appropriately promoting the curing reaction of the conductive material.

  In the formula (11), R1 and R2 each represent a hydrogen atom, a substituent represented by the following formula (11a), or a substituent represented by the following formula (11b). R1 and R2 may be the same or different.

  In the formula (11a) and the formula (11b), R3 is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxyl group having 1 to 20 carbon atoms, a halogen atom, a hydroxyl group, a carboxyl group, or 1 carbon atom. Represents -20 alkyl ester groups of carboxylic acid. The alkyl group may be linear or branched.

  Examples of the benzophenone derivative represented by the above formula (11) include benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, 4,4′-bis (dimethylamino) benzophenone and 4-benzoyl-4′-methyl. Examples thereof include diphenyl sulfide.

  The content of the sensitizer is not particularly limited. The content of the sensitizer is preferably 0.05 parts by weight or more, more preferably 0.1 parts by weight or more, preferably 3 parts by weight or less, more preferably 1 part by weight with respect to 100 parts by weight of the curable compound. Or less. A sensitizing effect is sufficiently obtained when the content of the sensitizer is not less than the above lower limit. When the content of the sensitizer is less than or equal to the above upper limit, light absorption is moderate and light is easily transmitted to the deep part of the conductive material layer.

  The conductive material preferably contains a silane coupling agent. The said silane coupling agent improves the adhesiveness by the hardened | cured material of an electroconductive material.

  Examples of the silane coupling agent include γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-isocyanatopropyltrimethoxysilane.

  The content of the silane coupling agent is not particularly limited. The content of the silane coupling agent is preferably 0.1 parts by weight or more, more preferably 0.5 parts by weight or more, preferably 10 parts by weight or less, more preferably 5 parts by weight with respect to 100 parts by weight of the curable compound. Less than parts by weight. When the content of the silane coupling agent is not less than the above lower limit, an effect of improving adhesiveness can be effectively obtained. When the content of the silane coupling agent is not more than the above upper limit, it is difficult for the excess silane coupling agent to bleed out.

  The conductive material may contain a curing retardant. Use of the curing retarder increases the pot life of the conductive material.

  It does not specifically limit as said hardening retarder, A polyether compound etc. are mentioned. It does not specifically limit as said polyether compound, Polyethylene glycol, polypropylene glycol, polytetramethylene glycol, a crown ether compound, etc. are mentioned. Of these, crown ether compounds are preferred.

  The crown ether compound is not particularly limited, and examples thereof include 12-crown-4, 15-crown-5, 18-crown-6, 24-crown-8, and compounds represented by the following formula (12). .

  In said formula (12), R1-R12 represents a hydrogen atom or a C1-C20 substituted or unsubstituted alkyl group, respectively. However, at least one of R1 to R12 represents an alkyl group having 1 to 20 carbon atoms. The substituted or unsubstituted alkyl group is one or more functional groups selected from the group consisting of an alkoxyl group having 1 to 20 carbon atoms, a halogen atom, a hydroxyl group, a carboxyl group, and a carboxylic acid alkyl ester group having 1 to 20 carbon atoms. It may be substituted with a group, and adjacent Rn and Rn + 1 (where n represents an even number of 1 to 12) may together form a cyclic alkyl skeleton. The C1-C20 alkoxyl group may be linear or branched.

  Of the compounds represented by the formula (12), a compound having at least one cyclohexyl group is preferable. The presence of the cyclohexyl group stabilizes the skeleton of the crown ether and increases the delay effect.

  Specific examples of the compound having a cyclohexyl group and represented by the above formula (12) include a compound represented by the following formula (12A).

  The compound represented by the chemical formula (12A) has two cyclohexyl groups at positions that are axisymmetric with respect to a line passing through the center of the 18-crown-6-ether molecule. For this reason, it is considered that the delay effect is enhanced without causing distortion or the like in the skeleton of the 18-crown-6-ether molecule.

  The content of the curing retarder is not particularly limited. The content of the curing retardant is preferably 0.05 parts by weight or more, more preferably 0.1 parts by weight or more, preferably 5 parts by weight or less, more preferably 3 parts by weight with respect to 100 parts by weight of the curable compound. Or less. When the content of the curing retarder is not less than the above lower limit, a retarding effect can be sufficiently obtained. When the content of the curing retarder is not more than the above upper limit, outgas hardly occurs when the conductive material is cured.

  The conductive material may contain a compound or an ion exchanger that reacts with an acid generated in the cured product in order to improve durability of the device electrode and the like.

  Examples of the compound that reacts with the generated acid include substances that neutralize the acid, such as carbonates or bicarbonates of alkali metals or alkaline earth metals. Specific examples of the compound that reacts with the generated acid include calcium carbonate, calcium hydrogen carbonate, sodium carbonate, sodium hydrogen carbonate and the like.

  As the ion exchanger, any of a cation exchange type, an anion exchange type, and a both ion exchange type can be used. In particular, a cation exchange type or a double ion exchange type capable of adsorbing chloride ions is preferable.

  The conductive material may contain a solvent. By using the solvent, the viscosity of the conductive material can be easily adjusted. Examples of the solvent include ethyl acetate, methyl cellosolve, toluene, acetone, methyl ethyl ketone, cyclohexane, n-hexane, tetrahydrofuran, and diethyl ether.

  The conductive material may contain various known additives such as a reinforcing agent, a softening agent, a plasticizer, an ultraviolet absorber, and an antioxidant as necessary.

(Other details of conductive material)
The method for producing the conductive material is not particularly limited. For example, using a mixer such as a homodisper, a homomixer, a universal mixer, a planetarium mixer, a kneader, or a three roll, the curable component and the conductive particles are necessary. Depending on the case, a method of mixing with other components may be mentioned.

  The conductive material is a paste-like or film-like conductive material, and is preferably a paste-like conductive material. The paste-like conductive material is a conductive paste. The film-like conductive material is a conductive film. When the conductive material is a conductive film, a film that does not include conductive particles may be laminated on the conductive film that includes the conductive particles.

  The conductive material according to the present invention is a conductive paste, and is preferably a conductive paste applied on a connection target member in a paste state.

  In addition, the conductive material according to the present invention is suitably used for electrical connection of electrodes in an organic EL display element. The conductive material according to the present invention is suitably used for electrical connection between the electrodes of the organic EL display element substrate. Examples of the organic EL display element substrate include an organic EL substrate including an organic EL element and a sealing substrate. The sealing substrate is a substrate for sealing the organic EL element. The conductive material according to the present invention is suitably used for electrical connection between an electrode of an organic EL substrate including an organic EL element and an electrode of a sealing substrate.

  The conductive material according to the present invention can be used for bonding various connection target members. The conductive material is preferably used for obtaining a connection structure in which the first and second connection target members are electrically connected. The conductive material is more preferably used to obtain a connection structure in which the electrodes of the first and second connection target members are electrically connected.

  FIG. 1 is a front sectional view schematically showing an example of a connection structure using a conductive material according to an embodiment of the present invention.

  A connection structure 1 shown in FIG. 1 includes a first connection target member 2, a second connection target member 4, and a connection portion that electrically connects the first and second connection target members 2 and 4. 3. The connecting portion 3 is a cured product layer and is formed by curing a conductive material including the conductive particles 5.

  The first connection target member 2 has a plurality of first electrodes 2a on the surface (upper surface). The second connection target member 4 has a plurality of second electrodes 4a on the surface (lower surface). The first electrode 2 a and the second electrode 4 a are electrically connected by one or a plurality of conductive particles 5. Therefore, the first and second connection target members 2 and 4 are electrically connected by the conductive particles 5.

  The connection between the first and second electrodes 2a and 4a is usually performed by connecting the first connection target member 2 and the second connection target member 4 with the first and second electrodes 2a and 4a through a conductive material. Is carried out by applying pressure when the conductive material is cured after being overlapped so as to face each other. Generally, the conductive particles 5 are compressed by pressurization.

  The first and second connection target members are not particularly limited. Specific examples of the first and second connection target members include electronic components such as semiconductor chips, capacitors, and diodes, and electronic components such as printed boards, flexible printed boards, and glass boards. . The conductive material is preferably a conductive material used for connecting electronic components.

  The method for manufacturing a connection structure according to the present invention includes a step of disposing a conductive material layer with the conductive material on the surface of the first connection target member, the first connection target member side of the conductive material layer, A step of disposing the second connection target member on the opposite surface; and a connection part for thermally connecting the conductive material layer to electrically connect the first and second connection target members. And forming it. In this case, the connection portion is formed by heating the conductive material layer by heating to a temperature of 120 ° C. or less without heating to a temperature exceeding 120 ° C. More preferably, the conductive material layer is heated to a temperature of 100 ° C. or lower without being heated to a temperature exceeding 100 ° C.

  Moreover, the connection structure 1 shown in FIG. 1 can be obtained as follows, for example, through the states shown in FIGS.

  As shown in FIG. 2A, a first connection target member 2 having a first electrode 2a on the surface (upper surface) is prepared. Next, a conductive material including a plurality of conductive particles 5 is disposed on the surface of the first connection target member 2, and the conductive material layer 3 </ b> A is formed on the surface of the first connection target member 2. At this time, it is preferable that one or a plurality of conductive particles 5 be disposed on the first electrode 2a.

  Next, the conductive material layer 3A is cured by irradiating the conductive material layer 3A with light. 2A to 2C, the conductive material layer 3A is B-staged by irradiating the conductive material layer 3A with light to advance the curing of the conductive material layer 3A. That is, as shown in FIG. 2B, the B-staged conductive material layer 3B is formed on the surface of the first connection target member 2. By the B-stage, the first connection target member 2 and the B-staged conductive material layer 3B are temporarily bonded. The B-staged conductive material layer 3B is a semi-cured product in a semi-cured state. The B-staged conductive material layer 3B is not completely cured, and thermal curing can further proceed. However, the conductive material layer 3A may be cured at once without irradiating the conductive material layer 3A with light or heating the conductive material layer 3A without forming the conductive material layer 3A into a B-stage. It is preferable to heat the conductive material layer 3A to thermally cure the conductive material layer 3A.

In order to effectively advance the curing of the conductive material layer 3A, the light irradiation intensity when irradiating with light is preferably in the range of 0.1 to 8000 mW / cm ² . The integrated light quantity is preferably 0.1 to 20000 J / cm ² . The light source used when irradiating light is not specifically limited. Examples of the light source include a light source having a sufficient light emission distribution at a wavelength of 420 nm or less. Specific examples of the light source include, for example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a chemical lamp, a black light lamp, a microwave excitation mercury lamp, a metal halide lamp, and an LED lamp.

  Next, as shown in FIG.2 (c), the 2nd connection object member 4 is laminated | stacked on the surface opposite to the 1st connection object member 2 side of the conductive material layer 3B made into B stage. The second connection target member 4 is laminated so that the first electrode 2a on the surface of the first connection target member 2 and the second electrode 4a on the surface of the second connection target member 4 face each other.

  Further, when the second connection target member 4 is laminated, the conductive material layer 3 </ b> B that has been B-staged is heated to further cure the conductive material layer 3 </ b> B that has been B-staged to form the connection portion 3. . However, the B-staged conductive material layer 3B may be heated before the second connection target member 4 is laminated. Furthermore, you may heat the conductive material layer 3B made into B stage after the lamination | stacking of the 2nd connection object member 4. FIG.

  The heating temperature for curing the conductive material layer 3A or the B-staged conductive material layer 3B by heating is preferably 50 ° C. or higher, more preferably 80 ° C. or higher. When the conductive material according to the present invention is used for electrical connection of electrodes in an organic EL display element, the heating temperature for curing the conductive material layer 3A or the B-staged conductive material layer 3B is 120. It is preferable that it is 100 degrees C or less.

  It is preferable to apply pressure when the B-staged conductive material layer 3B is cured. By compressing the conductive particles 5 between the first electrode 2a and the second electrode 4a by pressurization, the contact area between the first and second electrodes 2a, 4a and the conductive particles 5 can be increased. it can. For this reason, conduction reliability can be improved. Further, by compressing the conductive particles 5, even if the distance between the first and second electrodes 2a and 4a increases, the particle diameter of the conductive particles 5 increases so as to follow this expansion.

  By curing the B-staged conductive material layer 3 </ b> B, the first connection target member 2 and the second connection target member 4 are connected via the connection portion 3. In addition, the first electrode 2 a and the second electrode 4 a are electrically connected through the conductive particles 5. In this way, the connection structure 1 shown in FIG. 1 using a conductive material can be obtained. Here, since photocuring and thermosetting are used in combination, the conductive material can be cured in a short time.

  The conductive material according to the present invention includes, for example, a connection between a flexible printed circuit board and a glass substrate (FOG (Film on Glass)), a connection between a semiconductor chip and a flexible printed circuit board (COF (Chip on Film)), and a semiconductor chip and glass. It can be used for connection to a substrate (COG (Chip on Glass)) or connection between a flexible printed circuit board and a glass epoxy substrate (FOB (Film on Board)). Especially, the said electrically-conductive material is suitable for a FOG use or a COG use, and is more suitable for a COG use. The conductive material according to the present invention is preferably a conductive material used for connection between a flexible printed circuit board and a glass substrate or a connection between a semiconductor chip and a glass substrate, and is used for connection between the flexible printed circuit board and the glass substrate. More preferably, it is a conductive material.

  In the connection structure according to the present invention, it is preferable that the second connection target member and the first connection target member are a flexible printed circuit board and a glass substrate, or a semiconductor chip and a glass substrate. More preferably, they are a flexible printed circuit board and a glass substrate.

  The connection structure according to the present invention is preferably an organic EL display element. The electrodes in the organic EL display element may be electrically connected by conductive particles contained in the conductive material.

  The first and second connection target members are each preferably an organic EL display element substrate. The first and second connection target members are preferably first and second substrates which are substrates for organic EL display elements. It is preferable that the first connection target member and the second connection target member are an organic EL substrate and a sealing substrate including an organic EL element. In this case, the first connection target member may be the organic EL substrate and the second connection target member may be the sealing substrate, and the first connection target member may be the sealing substrate. In addition, the second connection target member may be the organic EL substrate. The connection structure is preferably an organic EL display element.

  The electrode width (first electrode width and second electrode width) is preferably 5 μm or more, more preferably 10 μm or more, preferably 500 μm or less, more preferably 300 μm or less. The inter-electrode width (the first inter-electrode width and the second inter-electrode width) is preferably 3 μm or more, more preferably 10 μm or more, preferably 500 μm or less, more preferably 300 μm or less. Further, L / S (line / space) as electrode width / interelectrode width is preferably 5 μm / 5 μm or more, more preferably 10 μm / 10 μm or more, preferably 500 μm / 500 μm or less, more preferably 300 μm / 300 μm or less. is there.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The present invention is not limited only to the following examples.

Example 1
(1) Preparation of conductive material:
Cations are generated in 50 parts by weight of a polyfunctional epoxy resin (“1032H60” manufactured by Mitsubishi Chemical Corporation) solid at 23 ° C. and 50 parts by weight of a bisphenol F epoxy resin (“EXA-835LV” manufactured by DIC) liquid at 23 ° C. SI-60L (San-Aid manufactured by Sanshin Chemical Co., Ltd.) 3 parts by weight and core-shell type acrylic rubber particles (“Metblene W-5500” manufactured by Mitsubishi Rayon Co., Ltd., average particle size 0.4 μm) 10 Part by weight, 10 parts by weight of silica (average particle diameter of 0.25 μm) as an inorganic filler, and 4 parts by weight of conductive particles A (average particle diameter of 10 μm) are added, and 5 minutes at 2000 rpm using a planetary stirrer. A conductive paste was obtained by stirring.

  The conductive particles A used are conductive particles having a conductive layer in which a nickel plating layer is formed on the surface of divinylbenzene resin particles and a gold plating layer is formed on the surface of the nickel plating layer. is there.

(2) Production of organic EL display element:
An organic EL substrate (first substrate) having an organic EL element and having an aluminum electrode pattern with an L / S of 50 μm / 50 μm and a length of 1 mm formed on the upper surface was prepared. In addition, a sealing substrate (second substrate) in which an aluminum electrode pattern having an L / S of 50 μm / 50 μm and a length of 2 mm was formed on the lower surface was prepared.

  A conductive paste layer was formed on the first substrate by applying the conductive paste immediately after fabrication to a width of 1.5 mm and a thickness of 40 μm using a dispenser. Next, the second substrate was laminated on the conductive paste layer so that the electrodes were opposed to each other to obtain a laminated body. The laminated body was cured by applying a pressure of 0.3 MPa at 100 ° C. for 15 minutes using a bonding apparatus to obtain an organic EL display element.

( Reference example 2 of organic EL display element )
An organic EL display element was obtained in the same manner as in Example 1 except that the heating temperature of the conductive paste layer was changed from 100 ° C. to 120 ° C.

(Example 3)
A conductive paste was obtained in the same manner as in Example 1 except that the organic particles were changed to core-shell structured fine particles (“F351” manufactured by Ganz Kasei Co., Ltd., average particle size: 0.3 μm). Using the obtained conductive paste, an organic EL display element was obtained in the same manner as in Example 1.

Example 4
A conductive paste was obtained in the same manner as in Example 1 except that the inorganic filler was changed to talc (“D-800” manufactured by Nippon Talc Co., Ltd., average particle diameter: 0.8 μm). Using the obtained conductive paste, an organic EL display element was obtained in the same manner as in Example 1.

(Example 5)
Except for changing 50 parts by weight of bisphenol F epoxy resin (“EXA-835LV” manufactured by DIC) to 50 parts by weight of liquid bisphenol E epoxy resin (“EPOX-MK R1710” manufactured by Printec) at 23 ° C. In the same manner as in Example 1, a conductive paste was obtained. Using the obtained conductive paste, an organic EL display element was obtained in the same manner as in Example 1.

(Example 6)
Except having changed the kind of cation generator from SI-60L (Sun Shin Aid made by Sanshin Chemical Co., Ltd.) to CXC-1612 ("K-pure CXC" made by K-pure), it carried out similarly to Example 1. A conductive paste was obtained. Using the obtained conductive paste, an organic EL display element was obtained in the same manner as in Example 1.

( Reference Example 7)
Except for adding 15 parts by weight of a thermosetting agent (imidazole compound, “2P-4MZ” manufactured by Shikoku Kasei Kogyo Co., Ltd.) without adding SI-60L, which is a cation generator, A conductive paste was obtained. Using the obtained conductive paste, an organic EL display element was obtained in the same manner as in Example 1.

(Comparative Example 1)
A conductive paste was obtained in the same manner as in Example 1 except that the organic particles and the inorganic filler were not blended. Using the obtained conductive paste, an organic EL display element was obtained in the same manner as in Example 1.

(Comparative Example 2)
A conductive paste was obtained in the same manner as in Example 1 except that no organic particles were blended. Using the obtained conductive paste, an organic EL display element was obtained in the same manner as in Example 1.

(Comparative Example 3)
A conductive paste was obtained in the same manner as in Example 1 except that the inorganic filler was not blended. Using the obtained conductive paste, an organic EL display element was obtained in the same manner as in Example 1.

(Evaluation)
(1) Minimum melt viscosity during curing of conductive material Using a rotary rheometer (STRESSTECH, manufactured by REOLOGICA), the minimum melt viscosity during curing of the conductive material is measured using a gap of 500 um, a frequency of 1 Hz, a strain amount of 1 rad, and a heating rate. Evaluation was made by setting the value at which the complex viscosity was the lowest at 10 ° C./min and the measurement temperature range of 30 ° C. to 120 ° C. as the lowest melt viscosity. The viscosity during curing of the conductive material was determined according to the following criteria.

[Minimum melt viscosity during curing of conductive material]
○: Minimum melt viscosity is 2 Pa · s or more and 10 Pa · s or less ×: Minimum melt viscosity is less than 2 Pa · s or exceeds 10 Pa · s (2) Moisture resistance The obtained conductive paste has a thickness of 100 μm. Then, it was coated on a constant temperature plate with a Baker type applicator (manufactured by Tester Sangyo Co., Ltd.). The film was obtained by heating at 100 ° C. for 30 minutes. The moisture permeability of the obtained film was measured by exposing it to conditions of 60 ° C. and 90% RH for 24 hours in accordance with JIS Z0208.

  The moisture permeability is generally measured by a moisture permeable cup as in JIS Z 0208, but can also be measured using PERMATRAN W3 / 33 manufactured by American Mocon.

  The moisture resistance was determined from the measured values of moisture permeability according to the following criteria.

[Criteria for moisture resistance]
○: Moisture permeability is 25 g / m ² or less Δ: Moisture permeability exceeds 25 g / m ² , 50 g / m ² or less ×: Moisture permeability exceeds 50 g / m ² (3) Presence of void In the device, it was observed whether or not a void was generated in the connection portion where the conductive material layer was cured. The presence or absence of voids was determined according to the following criteria.

[Criteria for the presence or absence of voids]
○: No void △: There is a void, but there is no void larger than the electrode width and interelectrode width ×: There is a void larger than the electrode width or interelectrode width (4) Conduction reliability (connection resistance value)
The connection resistance between the upper and lower electrodes of the obtained organic EL display element was measured by a four-terminal method. The average value of the connection resistance at 100 locations was calculated. Note that the connection resistance can be obtained by measuring the voltage when a constant current is passed from the relationship of voltage = current × resistance. The conduction reliability between the electrodes in the obtained organic EL display element was determined according to the following criteria.

[Judgment criteria for conduction reliability]
○○: Less than 3Ω ○: 3Ω or more, less than 4Ω △: 4Ω or more, less than 5Ω ×: 5Ω or more

DESCRIPTION OF SYMBOLS 1 ... Connection structure 2 ... 1st connection object member 2a ... 1st electrode 3 ... Connection part 3A ... Conductive material layer 3B ... Conductive material layer made into B stage 4 ... 2nd connection object member 4a ... 2nd 5 ... conductive particles 11 ... conductive particles 12 ... substrate particles 13 ... conductive layer

Claims (10)

Without heating to temperatures above 100 ° C., 100 ° C. is used is cured by heating to a temperature below and a Rushirubeden material used for electrical connection of the electrode in the organic electroluminescent display device,
A curable component, and organic particles, and an inorganic filler, and conductive particles seen including,
The curable component comprises a curable compound capable of being cured by heating, including a cation generator which generates cations by heating, conductive material. The conductive material according to claim 1, which is used for electrical connection between an electrode of an organic electroluminescence substrate including an organic electroluminescence element and an electrode of a sealing substrate. The conductive material according to claim 1 or 2 , wherein the organic particles are core-shell particles having a core and a shell disposed on a surface of the core. The core is formed of a first (meth) acrylic resin;
The conductive material according to claim 3 , wherein the shell is formed of a second (meth) acrylic resin. The conductive material according to claim 4 , wherein a glass transition temperature of the first (meth) acrylic resin is higher than a glass transition temperature of the second (meth) acrylic resin. The average particle diameter of the inorganic filler is 0.1μm or more and 1μm or less, a conductive material according to any one of claims 1-5. The conductive material according to any one of claims 1 to 6 , wherein the curable compound includes an epoxy compound that is liquid at 23 ° C and an epoxy compound that is solid at 23 ° C. The conductive particles, and the substrate particles, wherein and a base conductive layer disposed on the surface of the particles, the conductive material according to any one of claims 1-7. A first connection target member having a first electrode; a second connection target member having a second electrode; and a connection part electrically connecting the first and second connection target members. The first and second connection target members are substrates for organic electroluminescence display elements, and the first electrode and the second electrode are electrically connected by the conductive particles. a method of manufacturing a connection structure that,
A step of disposing a conductive material layer with the conductive material according to any one of claims 1 to 8 on the surface of the first connection target member;
Disposing the second connection target member on the surface opposite to the first connection target member side of the conductive material layer;
The connection part which does not heat to the temperature exceeding 100 degreeC, heats to the temperature of 100 degrees C or less, hardens the said conductive material layer, and electrically connects the said 1st, 2nd connection object member And a step of electrically connecting the first electrode and the second electrode with the conductive particles. The manufacturing method of the connection structure of Claim 9 whose said 1st connection object member and said 2nd connection object member are an organic electroluminescent board | substrate provided with an organic electroluminescent element, and a sealing substrate.

Images