JP2015110745A - Photocurable conductive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photocurable conductive composition comprising a photopolymerizable (meth)acrylate ester, a dendritic conductive powder, and a scaly conductive powder, and exhibiting a fast progress of photo-curing.SOLUTION: The photocurable conductive composition comprises (A) a photopolymerizable compound having a group expressed by formula (1):-OC(O)C(R)=CHand (B) a conductive powder satisfying the following conditions: (i) the conductive powder of the (B) component is a silver or silver-coated powder; (ii) the conductive powder of the (B) component is a mixture of (B-1) a dendritic conductive powder and (B-2) a scaly conductive powder; and (iii) the content of the conductive powder of the (B) component is 100 to 600 parts by mass with respect to 100 parts by mass of the photocurable conductive composition excluding the conductive powder of the (B) component. In formula (1), R represents H or a methyl group. The photocurable conductive composition further comprises an organic polymer having a hydrolyzable group bonded to Si and a Si-containing group that forms a siloxane bond to crosslink.

Description

  The present invention relates to a photocurable conductive composition having excellent conductivity, which contains a photopolymerizable (meth) acrylic acid ester, a dendritic conductive powder and a scaly conductive powder.

A conductive adhesive containing a conductive powder such as silver powder in a curable resin is used as a material for forming an electronic circuit, a solder alternative conductive material, or the like for cost reduction. In paragraph [0003] of Patent Document 1, when a conductive powder in which a dendritic (dendritic) conductive powder and a scaly (flaked) conductive powder are used in combination as a conductive powder, the conductivity is excellent. It is disclosed that an adhesive paste is obtained. However, the curable resin described in Patent Document 1 is not a photocurable resin.
Patent Document 2 discloses a photocurable conductive composition comprising a dendritic (dendritic) conductive powder and a flaky conductive powder in combination as a conductive powder. It is used as a material for forming electronic circuits.

  However, since the conductive powder normally does not transmit light, it is difficult to sufficiently cure the conductive powder when a large amount of the conductive powder is added to increase the conductivity. Although it may be possible to cure by increasing the irradiation time, productivity decreases. In addition, when using a photocurable conductive composition as a solder substitute conductive material for fixing an electronic component to an electronic circuit or the like, it is necessary to use the photocurable conductive composition thickly in order to obtain sufficient adhesive strength. There is. In this case, it may be difficult to cure to the inside of the used photocurable conductive composition. Thus, especially when adding a large amount of conductive powder to increase the conductivity, or when using it thickly because it is used like a solder alternative conductive material, the light of the photocurable conductive composition There is a problem that curability is lowered.

  Moreover, it is disclosed that it is preferable to use spherical conductive particles for the photocurable conductive composition in the paragraph [0011] of Patent Document 3 and the third page of Patent Document 4 and the lower 6 lines to the lower 3 lines. There is. However, it is difficult to increase the conductivity of a conductive composition using spherical conductive particles. A photocurable conductive composition in which photocuring proceeds even when a conductive powder in which a dendritic conductive powder and a scaly conductive powder are used in combination is desirable.

JP 11-152458 A JP 2000-219829 A JP 05-271576 A WO 2004-061006

  The present invention has been made in view of the above problems of the prior art, and the problem to be solved by the present invention includes photopolymerizable (meth) acrylic acid ester, dendritic conductive powder and scaly conductive powder. It is a photocurable conductive composition that provides a photocurable conductive composition in which photocuring is more likely to proceed.

  The present inventors have found that the above problem can be solved by using a scaly conductive powder having a small particle size distribution as a scaly conductive powder. That is, the present invention is the following photocurable conductive composition and an electrical product using the photocurable conductive composition.

(1) (A) Photopolymerizable compound having a group represented by the formula (1) —OC (O) C (R) ═CH ₂ (1)
In the formula (1), R represents a hydrogen atom or a methyl group, and (B) a photocurable conductive composition containing a conductive powder,
(I) The conductive powder of component (B) is silver or silver-coated powder,
(Ii) The conductive powder of component (B) is (B-1) dendritic conductive powder, and (B-2) 10% particle size by laser diffraction scattering type particle size distribution measurement method is D10, and 50% particle size is D50. When the 90% particle size is D90 and the standard deviation of the particle size is SD, SD / D50 is 0.5 or less and D90 / D10 is a mixture of flaky conductive powders of 4.0 or less. ,
(Iii) The content of the conductive powder of the component (B) is 100 to 600 parts by mass with respect to 100 parts by mass of the photocurable conductive composition excluding the solvent and the conductive powder of the component (B).
A photocurable conductive composition characterized by the above.
(2) (C) An organic polymer having a hydrolyzable group bonded to a silicon atom and having a silicon-containing group that can be cross-linked by forming a siloxane bond. A photocurable conductive composition.
(3) (C) An organic polymer having a hydrolyzable group bonded to a silicon atom and having a silicon-containing group that can be crosslinked by forming a siloxane bond is a crosslinkable silyl group-containing polyoxyalkylene polymer. And a photocurable conductive composition according to (1) or (2), which is at least one compound selected from the group consisting of a crosslinkable silyl group-containing (meth) acrylic polymer.
(4) The photocurable conductive composition according to any one of (1) to (3), which is used for bonding electronic components.
(5) An electric product using the photocurable conductive composition of (4).

  In addition to electronic devices such as electronic components and electronic circuits, any product that is designed to perform a desired operation by creating a current path is also included in the electrical product of the present invention.

  Since the photocurable conductive composition of the present invention uses a flaky conductive powder and a dendritic conductive powder having a small particle size distribution, light is easily transmitted and a flaky conductive powder having a large particle size distribution is used. Compared to the case, photocuring is more likely to proceed. Moreover, it is excellent also in electroconductivity compared with the case where the scale-like electroconductive powder with a large particle size distribution is used.

It is a schematic explanatory drawing which shows the flow which manufactures an electric product using the photocurable conductive composition which concerns on this invention, When (a) formed the metal wiring in the board | substrate, (b) is on the said metal wiring When an IC chip was placed on the photocurable conductive composition, (c) was applied with a photocurable conductive composition, and (d) was a photocurable conductive composition by irradiating the photocurable conductive composition with ultraviolet rays. When cured, each is shown. It is a schematic explanatory drawing which shows the other flow which manufactures an electric product using the photocurable conductive composition which concerns on this invention, (a) formed the metal wiring in the board | substrate, (b) is the said metal When the photocurable conductive composition was applied on the wiring, (c) developed adhesiveness by irradiating the photocurable conductive composition with ultraviolet rays, and (d) showed the adhesive properties. When IC chip was affixed with the expressed photocurable electroconductive composition, each is shown. It is the isometric view schematic which shows the state by which the metal wiring was given to the board | substrate. It is a perspective schematic diagram showing an example of the electric product manufactured using the photocurable conductive composition concerning the present invention.

The photopolymerizable compound (A) used in the present invention is a photopolymerizable compound having a group represented by the formula (1).
-OC (O) C (R) = CH ₂ (1)
In formula (1), R represents a hydrogen atom or a methyl group. Hereinafter, the group represented by the formula (1) is referred to as a (meth) acryloyloxy group. Methacrylic acid and acrylic acid are referred to as (meth) acrylic acid, methacrylic acid ester and acrylic acid ester are combined as (meth) acrylic acid ester, and acrylate and methacrylate are combined as (meth) acrylate.

  The compound having a (meth) acryloyloxy group as the component (A) preferably has no polar group, for example, an alkyl (meth) acrylate having an alkyl group having 1 to 12 carbon atoms, a branched alkyl having 13 to 20 carbon atoms. Alcohol (meth) acrylic acid esters and alicyclic (meth) acrylate monomers are preferred.

  Examples of the alkyl (meth) acrylate having an alkyl group having 1 to 12 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and n-butyl. (Meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, n-amyl (meth) acrylate, isoamyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) ) Acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate Isodecyl (meth) acrylate, dodecyl (meth) acrylate, lauryl (meth) acrylate. These may be used alone or in combination of two or more.

  Examples of the (meth) acrylic acid ester of the branched alkyl alcohol having 13 to 20 carbon atoms include, for example, isotetradecyl alcohol (also known as isomyristyl alcohol), isopentadecyl alcohol, isohexadecyl alcohol, isoheptadecyl alcohol, Examples include acrylic acid esters and methacrylic acid esters such as isooctadecyl alcohol (also known as isostearyl alcohol) and isonononadecyl alcohol. The branched acrylic acid ester and methacrylic acid ester may be used alone or in combination of two or more.

  As the alicyclic (meth) acrylate monomer, a (meth) acrylic acid ester monomer having a cyclic hydrocarbon group is preferable. For example, the alicyclic (meth) acrylate monomer is known in JP-A Nos. 61-136529 and 2-588529. Specific examples thereof include cyclohexyl (meth) acrylate, norbornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, isobornyl (meth) acrylate, and the like.

  As the component (A), a compound having a polar group can be used. For example, carboxyalkyl (meth) acrylates such as (meth) acrylic acid and carboxyethyl acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, caprolactone modified ( Monomers having a hydroxyl group such as (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate; dimethylaminomethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, diethylaminoethyl Examples thereof include nitrogen-containing compounds such as (meth) acrylates. By using the compound which has a polar group, the cohesion force of the photocurable conductive composition after hardening can be improved, and adhesiveness can be improved.

  Moreover, the (meth) acrylic acid ester which has a crosslinkable silicon group can be used as (A) component. When such a compound is used, the adhesiveness to the base material of the photocurable electrically conductive composition of this invention can be improved. Examples of such compounds include acryloylpropyltrimethoxysilane and methacryloylpropyltrimethoxysilane.

  Furthermore, in order to improve heat resistance, a polyfunctional acrylic monomer can be used as the component (A). As the polyfunctional acrylic monomer, a monomer having a (meth) acryloyl group is preferable. The polyfunctional acrylic monomer is not particularly limited. For example, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6- Bifunctional vinyl monomers such as hexadiol di (meth) acrylate and trimethylolpropane di (meth) acrylate, trifunctional vinyl monomers such as trimethylolpropane tri (meth) acrylate and pentaerythritol tri (meth) acrylate, pentaerythritol Examples include tetra- or higher functional vinyl monomers such as tetra (meth) acrylate and dipentaerythritol hexa (meth) acrylate. A bifunctional vinyl monomer or a trifunctional vinyl monomer is preferred, and a bifunctional vinyl monomer is more preferred.

  Moreover, you may use photopolymerizable oligomers, such as a polyester (meth) acrylate, an epoxy (meth) acrylate, a polyether (meth) acrylate, and a urethane (meth) acrylate oligomer as (A) component.

  Examples of the polyester (meth) acrylate oligomer include a dehydration condensate of polyester polyol and (meth) acrylic acid. Here, examples of the polyester polyol include a reaction product of a polyol and a carboxylic acid or an anhydride thereof.

  Polyols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, butylene glycol, polybutylene glycol, tetramethylene glycol, hexamethylene glycol, neo Low molecular weight polyols such as pentyl glycol, cyclohexanedimethanol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, trimethylolpropane, glycerin, pentaerythritol and dipentaerythritol, and their alkylene oxide adducts Etc.

  As the carboxylic acid or anhydride thereof, dibasic acids such as orthophthalic acid, isophthalic acid, terephthalic acid, adipic acid, succinic acid, fumaric acid, maleic acid, hexahydrophthalic acid, tetrahydrophthalic acid and trimellitic acid, or anhydrides thereof Thing etc. are mentioned.

  Epoxy (meth) acrylate is a compound obtained by adding (meth) acrylic acid to an epoxy resin. Examples of the epoxy resin include aromatic epoxy resins and aliphatic epoxy resins.

  Specific examples of the aromatic epoxy resin include resorcinol diglycidyl ether; di- or polyglycidyl ether of bisphenol A, bisphenol F, bisphenol S, bisphenol fluorene or an alkylene oxide adduct thereof; phenol novolac type epoxy resin and cresol novolac type Novolak type epoxy resins such as epoxy resins; glycidyl phthalimide; o-phthalic acid diglycidyl ester and the like. In addition to these, the document “Epoxy Resin—Recent Advances” (Shisodo, published in 1990), Chapter 2 and the document “Polymer Processing”, Vol. 9, Volume 22 No. Epoxy Resin [Polymer Publications, Compounds published on pages 4 to 6 and pages 9 to 16 of 1973.

  Specific examples of the aliphatic epoxy resin include diglycidyl ethers of alkylene glycols such as ethylene glycol, propylene glycol, 1,4-butanediol and 1,6-hexanediol; diglycidyl ethers of polyethylene glycol and polypropylene glycol, etc. Diglycidyl ethers of polyalkylene glycols; diglycidyl ethers of neopentyl glycol, dibromoneopentyl glycol and alkylene oxide adducts thereof; di- or triglycidyl ethers of trimethylolethane, trimethylolpropane, glycerin and alkylene oxide adducts thereof; Of polyhydric alcohols such as di-, tri- or tetraglycidyl ethers of pentaerythritol and its alkylene oxide adducts Ether; hydrogenated bisphenol A and di- or polyglycidyl ethers of alkylene oxide adducts; tetrahydrophthalic acid diglycidyl ether; hydroquinone diglycidyl ether, and the like.

  In addition to these, the compounds described on pages 3 to 6 of the above-mentioned document “Polymer Processing”, separate volume epoxy resin, can be mentioned. In addition to these aromatic epoxy resins and aliphatic epoxy resins, epoxy compounds having a triazine nucleus in the skeleton, such as TEPIC (Nissan Chemical Co., Ltd.), Denacol EX-310 (Nagase Kasei Co., Ltd.), etc. can be mentioned. , Compounds described on pages 289 to 296 of the above-mentioned document “Polymer Processing”, separate volume epoxy resin, and the like. In the above, the alkylene oxide of the alkylene oxide adduct is preferably ethylene oxide or propylene oxide.

  Polyether (meth) acrylate oligomers include polyalkylene glycol (meth) diacrylates, such as diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, dipropylene glycol di ( Examples include meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, and polytetramethylene glycol di (meth) acrylate.

  Examples of the urethane (meth) acrylate oligomer include a reaction product obtained by further reacting a hydroxyl group-containing (meth) acrylate with a polyol and an organic polyisocyanate reaction product. Here, examples of the polyol include a low molecular weight polyol, polyethylene glycol, and polyester polyol. Examples of the low molecular weight polyol include ethylene glycol, propylene glycol, cyclohexanedimethanol and 3-methyl-1,5-pentanediol, and examples of the polyether polyol include polyethylene glycol and polypropylene glycol. Is a reaction product of these low molecular weight polyols and / or polyether polyols and acid components such as dibasic acids such as adipic acid, succinic acid, phthalic acid, hexahydrophthalic acid and terephthalic acid, or anhydrides thereof. . Examples of the organic polyisocyanate include tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. Examples of the hydroxyl group-containing (meth) acrylate include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate. These urethane (meth) acrylate oligomers may be produced according to a conventionally known synthesis method. For example, in the presence of an addition catalyst such as dibutyltin dilaurate, an organic isocyanate and a polyol component to be used are heated and stirred to carry out an addition reaction, and further a hydroxyalkyl (meth) acrylate is added, followed by heating and stirring to carry out an addition reaction.

  The molecular weight of the urethane (meth) acrylate oligomer is preferably 500 to 10,000 in terms of number average molecular weight because the cured film of the resulting photocurable conductive composition has excellent durability. More preferably, it is 1,000-10,000.

  As the component (A) which is an oligomer, an oligomer having a (meth) acryloyloxy group whose main chain is a (meth) acrylic acid ester polymer can also be used. Such a polymer is preferably produced by anionic polymerization or radical polymerization, and radical polymerization is more preferable because of the versatility of the monomer or ease of control. Among radical polymerizations, it is preferably produced by living radical polymerization or radical polymerization using a chain transfer agent, more preferably a living radical polymerization method, and particularly preferably an atom transfer radical polymerization method. When the living radical polymerization method is used, a polymer having a (meth) acryloyloxy group at the end of the polymer chain can be obtained.

  The radical polymerization method used in the production of a (meth) acrylic acid ester polymer uses an azo compound, a peroxide, or the like as a polymerization initiator, and simply combines a monomer having a specific functional group and a vinyl monomer. It can be classified into “general radical polymerization method” for polymerization and “controlled radical polymerization method” in which a specific functional group can be introduced at a controlled position such as a terminal.

  The “general radical polymerization method” is a simple method. However, in this method, a monomer having a specific functional group is introduced into the polymer only in a probabilistic manner, so an attempt is made to obtain a polymer having a high functionalization rate. In such a case, it is necessary to use this monomer in a considerably large amount, and conversely, in the case of using a small amount, there is a problem that the proportion of the polymer in which this specific functional group is not introduced becomes large. Moreover, since it is free radical polymerization, there is also a problem that only a polymer having a wide molecular weight distribution and a high viscosity can be obtained.

  The “controlled radical polymerization method” further includes a “chain transfer agent method” in which a vinyl polymer having a functional group at a terminal is obtained by polymerization using a chain transfer agent having a specific functional group, It can be classified as “living radical polymerization method” in which a polymer having a molecular weight almost as designed can be obtained by growing the terminal without causing a termination reaction or the like.

  In the “chain transfer agent method”, a polymer having a high functionalization rate can be obtained, but a chain transfer agent having a considerably large amount of a specific functional group with respect to the initiator is required. There is an economic problem. Further, like the above-mentioned “general radical polymerization method”, there is also a problem that only a polymer having a wide molecular weight distribution and high viscosity can be obtained because of free radical polymerization.

  Unlike these polymerization methods, the “living radical polymerization method” is a radical polymerization that is difficult to control because the polymerization rate is high and a termination reaction due to coupling between radicals is likely to occur. It is difficult to obtain a polymer having a narrow molecular weight distribution (Mw / Mn is about 1.1 to 1.5), and the molecular weight can be freely controlled by the charging ratio of the monomer and the initiator.

  Therefore, the “living radical polymerization method” can obtain a polymer having a narrow molecular weight distribution and a low viscosity, and a monomer having a specific functional group can be introduced at almost any position of the polymer. The production method of the vinyl polymer having the specific functional group is more preferable.

  In the narrow sense, living polymerization refers to polymerization in which the terminal always has activity and the molecular chain grows, but in general, the terminal is inactivated and the terminal is activated. Pseudo-living polymerization in which is grown while in equilibrium. The definition in the present invention is also the latter.

  The “living radical polymerization method” has been actively researched by various groups in recent years. Examples thereof include those using a cobalt porphyrin complex as shown in Journal of the American Chemical Society (J. Am. Chem. Soc.), 1994, 116, 7943, Macro Molecule. Macromolecules, 1994, Vol. 27, p. 7228, using radical scavengers such as nitroxide compounds, etc., “Atom transfer radical polymerization using organic halides as initiators and transition metal complexes as catalysts. (Atom Transfer Radical Polymerization: ATRP).

  Among the “living radical polymerization methods”, the “atom transfer radical polymerization method” for polymerizing vinyl monomers using an organic halide or a sulfonyl halide compound as an initiator and a transition metal complex as a catalyst is the above-mentioned “living radical polymerization method”. In addition to the characteristics of ”, it has a halogen, which is relatively advantageous for functional group conversion reaction, at the end, and has a high degree of freedom in designing initiators and catalysts. Therefore, production of vinyl polymers having specific functional groups The method is more preferable.

  As the atom transfer radical polymerization method, for example, Matyjaszewski et al., Journal of the American Chemical Society (J. Am. Chem. Soc.) 1995, 117, 5614, Macromolecules. 1995, 28, 7901, Science 1996, 272, 866, WO 96/30421 pamphlet, WO 97/18247 pamphlet or Sawamoto et al., Macromolecules 1995, 28, And the method described on page 1721.

  There is no particular restriction as to which of these methods is used, but basically, a controlled radical polymerization method is used, and a living radical polymerization method is preferred from the viewpoint of ease of control, especially an atom transfer radical polymerization method. Is preferred.

  In the atom transfer radical polymerization, the transition metal complex used as a polymerization catalyst is not particularly limited, but is preferably zero-valent copper, monovalent copper, divalent ruthenium, divalent iron, or divalent nickel. A transition metal complex having a central metal as a central metal, particularly preferably a copper complex.

  As a method for introducing a (meth) acryloyloxy group into the polymer, a known method can be used. Examples thereof include the methods described in paragraphs [0080] to [0091] of JP-A No. 2004-203932. Other than these methods, there is a method in which a monomer having an isocyanate group and a (meth) acryloyloxy group is reacted with a (meth) acrylic polymer having a hydroxyl group terminal. For example, 2- (meth) acryloyloxyethyl isocyanate is used. The method to use is mentioned.

  The molecular weight distribution of the (meth) acryloyloxy group-containing oligomer (ratio of mass average molecular weight (Mw) and number average molecular weight (Mn) measured by gel permeation chromatography (GPC)) is not particularly limited, but preferably Is less than 1.8, more preferably 1.7 or less, even more preferably 1.6 or less, particularly preferably 1.5 or less, particularly preferably 1.4 or less, and most preferably 1.3 or less.

  The lower limit of the number average molecular weight of the (meth) acryloyloxy group-containing oligomer is preferably 500, more preferably 3,000, and the upper limit is preferably 100,000, more preferably 40,000. When the molecular weight is less than 500, the original characteristics of the polymer tend to be hardly expressed, and when it exceeds 100,000, handling tends to be difficult.

  In the (meth) acryloyloxy group-containing oligomer, an oligomer having two or more (meth) acryloyl groups may be used, and a part of the ends are capped with an alkoxy group such as an ethoxy group or a phenoxy group or an aryloxy group (meth) An oligomer having one acryloyl may be used.

  (A) A component may be used independently and may use 2 or more types together. As the component (A), it is desirable to select the component (A) so that the polymer after polymerization has a low glass transition temperature (Tg). It is desirable to select the component (A) so that a polymer having a Tg of 0 ° C. or lower, further −20 ° C. or lower is produced. For this purpose, the (A) component has an alcohol having an alkyl group having 4 or more carbon atoms with an ester of (meth) acrylic acid, an ester of polypropylene glycol with (meth) acrylic acid or an alkyl group having 4 or more carbon atoms. It is preferable to use an oligomer having a (meth) acryloyl group which is a polymer of (meth) acrylic acid ester. Of these three components, two components may be used in combination as component (A), or three components may be used in combination as component (A). Tg is measured by differential scanning calorimetry (DSC method).

  In the present invention, a photopolymerizable dendrimer compound having a group represented by the formula (1) may be used as the component (A). Dendrimer compounds are compounds having a dendritic structure, but unlike conventional linear polymers and branched polymers, they are highly branched by repeating a three-dimensional branched structure. Therefore, it is possible to introduce a large number of reactive functional groups on the outermost surface, the curability is excellent, and the viscosity can be suppressed lower than that of a linear polymer having the same molecular weight. As dendritic polymers, dendrimers, linear-dendritic polymers, dendrigraft polymers, hyperbranched polymers, star hyperbranched polymers, and hypergraft polymers are known. Of these, dendrimers or hyperbranched polymers are preferred.

  Specific examples of the dendritic polymer having a (meth) acryloyl group include Biscote # 1000 (manufactured by Osaka Organic Chemical Industry Co., Ltd.). This “Biscoat # 1000” is a dendrimer-based compound having a functional group branched with a pentaerythritol-based compound as a core, and has an acryloyloxy group on the outermost surface, and can be suitably used.

  The amount of the photopolymerizable dendrimer compound used is preferably 0.1 to 10% by mass relative to the photopolymerizable compound of component (A). More preferably, it is 0.5-5 mass%.

In the present invention, conductive powder is used as the component (B). As the conductive powder, silver powder or silver-coated powder is used. Silver-coated copper powder is preferred as the silver-coated powder. In the present invention, a mixture of (B-1) dendritic (dendritic) conductive powder and (B-2) scaly (flaky) conductive powder is used as the component (B). (B-1) Dendritic conductive powder has a 50% particle diameter (D50) of 3 to 30 μm, more preferably 4.0 to 25.0 μm, and a specific surface area of 0.3 to 1.5 m ^2. / G, further 0.4 to 1.40 m ² / g and tap density of 0.3 to 2.0 g / cm ³ are preferable. Such a dendritic conductive powder is described in JP-A-2004-068111. The specific surface area is measured by the BET single point method.

(B-2) The flaky (scale-like) conductive powder has a 10% particle size of D10, a 50% particle size of D50, a 90% particle size of D90 and a standard particle size by a laser diffraction scattering particle size distribution measurement method. When the deviation is SD, a scaly conductive powder having SD / D50 of 0.5 or less and D90 / D10 of 4.0 or less is used. The preferable range of D90 / D10 is 3.0 or less. The component (B-2) preferably has a 50% particle size (D50) of 1.0 to 10.0 μm, a specific surface area of 0.3 to 1.5 m ² / g, and a tap density of 1.0 to 7. 0 g / cm ³ is preferred.

  The (B-1) component and the (B-2) component preferably have a mass ratio of 30/70 to 95/5. In addition, in order to improve the affinity with the organic component in the photocurable conductive composition and improve the dispersibility of the conductive powder in the photocurable conductive composition, a process for producing the conductive powder It is also preferable to treat the powder surface during or after production. As the surface treatment agent, a surfactant or an organic compound can be used.

  (B) The usage-amount of the electroconductive powder of a component is 100-600 mass parts with respect to 100 mass parts of photocurable conductive compositions except the solvent and the electroconductive powder of the (B) component. 100-500 mass parts is preferable, 100-400 mass parts is more preferable, 100-200 mass parts is especially preferable. If it is less than 100 parts by mass, the conductivity will be low, and if it exceeds 600 parts by mass, the viscosity of the photocurable conductive composition will increase and workability will decrease. Furthermore, in order to adjust the resistance value, other conductive metals such as gold, platinum, palladium, rhodium and the like may be added. These conductive powders may be used by mixing two or more kinds of powders having various shapes such as a shape, an average particle diameter, a specific surface area, and a tap density in order to adjust conductivity.

  In the photocurable conductive composition of the present invention, (C) an organic polymer having a crosslinkable silicon group may be used. When such a polymer is used, the adhesion strength to the adherend is improved, or the tackiness of the photocurable conductive composition is exhibited after light irradiation as described in JP-T-2009-530441. An adherend such as an electronic component can be temporarily fixed.

  The crosslinkable silicon group is a group having a hydrolyzable group bonded to a silicon atom and capable of crosslinking by forming a siloxane bond. As a representative example, the formula (2):

(In the formula, R ¹ represents an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or R ² ₃ SiO— ^{(R 2} is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, ^{R 2} three aryl group or an aralkyl group having 7 to 20 carbon atoms of 6 to 20 carbon atoms with the same And may be different, and when two or more R ¹ are present, they may be the same or different, and X is a hydrolysis. When two or more X are present, they may be the same or different, a is 0, 1, 2 or 3, b is 0, 1 or 2; Also, n formulas (3):

B in need not be the same. n shows the integer of 0-19. However, a + (sum of b) ≧ 1 is satisfied. ).
The hydrolyzable group can be bonded to one silicon atom in the range of 1 to 3, and a + (sum of b) is preferably in the range of 1 to 5.
The number of silicon atoms forming the crosslinkable silicon group may be one or two or more, but in the case of silicon atoms linked by a siloxane bond or the like, there may be about 20 silicon atoms.
Formula (4):

A crosslinkable silicon group represented by the formula (wherein R ¹ , X and a are the same as described above) is preferable from the viewpoint of easy availability. In the crosslinkable silicon group of the formula (4), a is preferably 2 or 3. When a is 3, the curing rate is higher than when a is 2.

Specific examples of R ¹ include an alkyl group such as a methyl group and an ethyl group, a cycloalkyl group such as a cyclohexyl group, an aryl group such as a phenyl group, an aralkyl group such as a benzyl group, and R ² ₃ SiO—. And triorganosiloxy group. Of these, a methyl group is preferred.

  It does not specifically limit as a hydrolysable group shown by said X, What is necessary is just a conventionally well-known hydrolysable group. Specific examples include a hydrogen atom, a halogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, a mercapto group, and an alkenyloxy group. Among these, a hydrogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an aminooxy group, a mercapto group, and an alkenyloxy group are preferable, and an alkoxy group, an amide group, and an aminooxy group are more preferable. An alkoxy group is particularly preferred from the viewpoint of mild hydrolysis and easy handling. Among the alkoxy groups, those having a smaller number of carbon atoms have higher reactivity, and the reactivity increases as the number of carbon atoms increases in the order of methoxy group> ethoxy group> propoxy group. Although it can be selected according to the purpose and application, a methoxy group or an ethoxy group is usually used.

Specific examples of the crosslinkable silicon group include trialkoxysilyl groups such as a trimethoxysilyl group and a triethoxysilyl group, dialkoxy such as —Si (OR ′) ₃ , a methyldimethoxysilyl group, and a methyldiethoxysilyl group. And a silyl group, —SiR ¹ (OR ′) ₂ . Here, R ¹ is the same as described above, and R ′ is an alkyl group such as a methyl group or an ethyl group.
Further, the crosslinkable silicon group may be used alone or in combination of two or more. The crosslinkable silicon group can be present in the main chain, the side chain, or both. It is preferable that a crosslinkable silicon group is present at the end of the molecular chain from the viewpoint of excellent cured product properties such as tensile properties of the cured product.

  Crosslinkable silicon groups should be present in an average of 1.0 to 5 and preferably 1.1 to 3 in one molecule of the polymer. When the number of crosslinkable silicon groups contained in the molecule is less than one, the curability is insufficient, and when the number is too large, the network structure becomes too dense, and good mechanical properties are not exhibited.

  The main chain skeleton of the organic polymer having a crosslinkable silicon group as component (C) is not particularly limited, and those having various main chain skeletons can be used. Specifically, polyoxyalkylene polymers, poly (meth) acrylic acid alkyl ester polymers, ethylene-propylene copolymers, polyisobutylene, copolymers of isobutylene and isoprene, polychloroprene, polyisoprene, Copolymers of isoprene or butadiene and acrylonitrile and / or styrene, polybutadiene, copolymers of isoprene or butadiene and acrylonitrile, and / or styrene, and hydrogenation obtained by hydrogenating these polyolefin polymers Hydrocarbon polymers such as polyolefin polymers; condensation polymers of polybasic acids such as adipic acid, terephthalic acid, and succinic acid and polyhydric alcohols such as bisphenol A, ethylene glycol, and neopentyl glycol, and the opening of lactones. Polymers such as ring polymers Ester polymer: nylon 6 by ring-opening polymerization of ε-caprolactam, nylon 6.6 by condensation polymerization of hexamethylenediamine and adipic acid, nylon 6.10 by condensation polymerization of hexamethylenediamine and sebacic acid, ε-aminoundecane Nylon 11 by acid condensation polymerization, nylon 12 by ring-opening polymerization of ε-aminolaurolactam, polyamide polymer such as copolymer nylon having two or more components among the above nylons; polysulfide polymer; for example, bisphenol Examples thereof include polycarbonate polymers and diallyl phthalate polymers produced by condensation polymerization from A and carbonyl chloride.

  (C) The organic polymer having a crosslinkable silicon group is at least one selected from the group consisting of a crosslinkable silyl group-containing polyoxyalkylene polymer and a crosslinkable silyl group-containing (meth) acrylic polymer. Compounds are preferred.

  When a poly (meth) acrylic acid alkyl ester polymer is used as the component (C), the weather resistance of the cured product, the adhesion to the substrate or the chemical resistance can be improved. Further, when a poly (meth) acrylic acid alkyl ester polymer having a high Tg as the component (C), for example, a polymer having a Tg of 10 ° C. or higher is used, when the photocurable conductive composition of the present invention is photopolymerized, There is an advantage that tackiness is easily developed. This tendency is particularly great when the component (A) is selected so that the polymer after polymerization has a low glass transition temperature (Tg). In order to obtain a polymer having a high Tg, a monomer such as methyl methacrylate known to give a polymer having a high Tg may be used. Moreover, Tg can be adjusted by making it copolymerize with another acrylic monomer. A preferred Tg is 50 ° C. or higher. The poly (meth) acrylic acid alkyl ester polymer is essentially a polymer having a repeating unit represented by the formula (5).

(Wherein R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents an alkyl group)
R ⁴ in Formula (5) is an alkyl group, and an alkyl group having 1 to 30 carbon atoms is preferable. R ⁴ may be linear or branched. Moreover, the substituted alkyl group which has a halogen atom, a phenyl group, an amino group, or a glycidyl group may be sufficient. Examples of R ⁴ include methyl group, ethyl group, propyl group, n-butyl group, t-butyl group, 2-ethylhexyl group, lauryl group, tridecyl group, cetyl group, stearyl group, and behenyl group. it can.

  The molecular chain of the (meth) acrylic acid alkyl ester polymer consists essentially of the monomer unit of the formula (5), and the term “essentially” as used herein means that of the formula (5) present in the polymer. It means that the total of monomer units exceeds 50% by mass. The total of the monomer units of the formula (5) is preferably 70% by mass or more.

  Examples of monomer units other than formula (5) include (meth) acrylic acid such as acrylic acid and methacrylic acid; amide groups such as acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, and aminoethyl Monomers containing amino groups such as vinyl ether; and other monomer units derived from acrylonitrile, styrene, α-methylstyrene, alkyl vinyl ether, vinyl chloride, vinyl acetate, vinyl propionate, ethylene and the like.

  The (meth) acrylic acid alkyl ester polymer having a crosslinkable silicon group can usually be obtained by radical copolymerization of a (meth) acrylic acid alkyl ester and a (meth) acrylic acid alkyl ester having a crosslinkable silicon group. . Further, when an initiator having a crosslinkable silicon group or a chain transfer agent having a crosslinkable silicon group is used, the crosslinkable silicon group can be introduced into the molecular chain terminal.

  JP 2001-040037 A, JP 2003-048923 A and JP 2003-048924 A have a crosslinkable silicon group (meth) obtained by using a mercaptan having a crosslinkable silicon group and a metallocene compound. Acrylic acid alkyl ester polymers are described. Moreover, the synthesis example of Unexamined-Japanese-Patent No. 2005-026881 describes the (meth) acrylic-acid alkylester type polymer which has a crosslinkable silicon group by high temperature continuous polymerization.

  As disclosed in JP-A-2000-086999, a (meth) acrylic acid alkyl ester-based polymer having a crosslinkable silicon group, in which a crosslinkable silicon group is introduced at a high ratio at the molecular chain terminal, Are known. Since such a polymer is produced by living radical polymerization, a crosslinkable silicon group can be introduced into the molecular chain terminal at a high rate. In the present invention, a (meth) acrylic acid alkyl ester polymer as described above can be used.

  When the component (C) is a polyoxyalkylene polymer, the polyoxyalkylene polymer is essentially a polymer having a repeating unit represented by the formula (6).

(Wherein R ⁵ is a divalent organic group)
R ⁵ in Formula (6) is preferably a linear or branched alkylene group having 1 to 14 carbon atoms, and more preferably 2 to 4 carbon atoms.
Specific examples of the repeating unit represented by the formula (6) include, for example,

Etc. The main chain skeleton of the polyoxyalkylene polymer may be composed of only one type of repeating unit, or may be composed of two or more types of repeating units. In particular, it is preferably made of a polymer mainly composed of oxypropylene.

  The molecular weight of the polyoxyalkylene polymer having a crosslinkable silicon group is preferably 5,000 to 50,000. In addition, the number average molecular weight as used in the field of this invention means the polystyrene conversion molecular weight by gel permeation chromatography. When the number average molecular weight is less than 5,000, the adhesive strength may not be sufficient, and when it exceeds 50,000, the viscosity of the photocurable conductive composition may increase and workability may decrease.

  The polyoxyalkylene polymer having a crosslinkable silicon group may be linear or branched.

  As a method for synthesizing a polyoxyalkylene polymer, for example, a polymerization method using an alkali catalyst such as KOH, for example, JP-A Nos. 61-197631, 61-215622, 61-215623, and 61-215623 can be used. Polymerization methods using an organoaluminum-porphyrin complex catalyst obtained by reacting an organoaluminum compound with porphyrin as shown, for example, double metal cyanide complexes shown in JP-B-46-27250 and JP-B-59-15336 Examples of the polymerization method using a catalyst include, but are not limited to, a polymerization method. A polyoxyalkylene system having a high molecular weight with a number average molecular weight of 6,000 or more and Mw / Mn of 1.6 or less and a narrow molecular weight distribution according to a polymerization method using an organoaluminum-porphyrin complex catalyst or a polymerization method using a double metal cyanide complex catalyst A polymer can be obtained.

  The main chain skeleton of the polyoxyalkylenes may contain other components such as a urethane bond component. Examples of the urethane bond component include aromatic polyisocyanates such as toluene (tolylene) diisocyanate, diphenylmethane diisocyanate and xylylene diisocyanate; aliphatic polyisocyanates such as isophorone diisocyanate and hexamethylene diisocyanate and polyoxyalkylenes having a hydroxyl group; What can be obtained from this reaction can be mentioned.

  The introduction of a crosslinkable silicon group into a polyoxyalkylene polymer can be performed on a polyoxyalkylene polymer having a functional group such as an unsaturated group, a hydroxyl group, an epoxy group or an isocyanate group in the molecule. The reaction can be carried out by reacting a compound having a reactive functional group and a crosslinkable silicon group. This method (hereinafter referred to as polymer reaction method) is also suitably used for polyester polymers, polyamide polymers, and polymers of unsaturated monomers obtained by living polymerization. This is because these polymers have a functional group such as a hydroxyl group at the end of the molecular chain, and therefore it is easy to introduce a crosslinkable silicon group at the end.

  As a specific example of the polymer reaction method, a hydrosilane or mercapto compound is produced by reacting an unsaturated group-containing oxyalkylene polymer with a hydrosilane having a crosslinkable silicon group or a mercapto compound having a crosslinkable silicon group to form a crosslinkable silicon group. The method of obtaining the oxyalkylene type polymer which has is mentioned. The unsaturated group-containing oxyalkylene polymer has an active group and an unsaturated group which are reactive to the functional group, such as an unsaturated halogen compound, in the oxyalkylene polymer having a functional group such as a hydroxyl group. By reacting an organic compound, an oxyalkylene polymer containing an unsaturated group can be obtained.

  Other specific examples of the polymer reaction method include a method of reacting a polyoxyalkylene polymer having a hydroxyl group at a terminal with a compound having an isocyanate group and a crosslinkable silicon group, or an oxyalkylene polymer having an isocyanate group at a terminal. A method of reacting a compound with a compound having an active hydrogen group such as a hydroxyl group or an amino group and a crosslinkable silicon group can be given. When an isocyanate compound is used, an oxyalkylene polymer having a crosslinkable silicon group can be easily obtained. The polymer reaction method can be applied to polymers other than polyoxyalkylene polymers.

  Specific examples of the polyoxyalkylene polymer having a crosslinkable silicon group include JP-B Nos. 45-36319, 46-12154, JP-A Nos. 50-156599, 54-6096, and 55-13767. JP-A-57-164123, JP-B-3-2450, JP-A-2005-213446, JP-A-2005-306871, International Publication Patent WO2007-040143, US Patents 3,632,557, 4,345,053. , 4,960,844, etc., can be mentioned.

  In the present invention, as described above, when a poly (meth) acrylic acid alkyl ester polymer having a Tg of 10 ° C. or higher is used as the component (C), there is an advantage that tackiness is easily developed. When a polyoxyalkylene polymer having a crosslinkable silicon group having a Tg of 0 ° C. or less and / or a poly (meth) acrylic acid alkyl ester polymer is added to this polymer, the tackiness is easily exhibited when photopolymerized. And there is an advantage that the adhesion of the final cured product to the substrate is improved. Mixing ratio of poly (meth) acrylic acid alkyl ester polymer having Tg of 10 ° C. or higher and polyoxyalkylene polymer having a crosslinkable silicon group having Tg of 0 ° C. or lower and / or poly (meth) acrylic acid alkyl ester polymer Is from 1: 5 to 5: 1 by weight, preferably from 1: 3 to 1: 1. (C) As for the usage-amount of the organic polymer which has a crosslinkable silicon group of a component, 40-200 mass parts is preferable with respect to 100 mass parts of photopolymerizable compounds of a (A) component.

  The photocurable conductive composition of the present invention further includes a photo radical initiator, a silanol condensation catalyst, a resin filler, a dehydrating agent, a light shielding material, a filler other than the resin filler and the light shielding material, an antioxidant, a plasticizer, Reactive diluent, light stabilizer, adhesion promoter, solvent, photosensitizer, flame retardant, radical inhibitor, metal deactivator, ozone degradation inhibitor, phosphorus peroxide decomposer, lubricant, foaming An agent may be added. These various additives may be used alone or in combination of two or more. Specific examples of such additives include, for example, each specification of JP-B-4-69659, JP-B-7-108928, JP-A-63-254149, JP-A-64-22904, and the like. It is described in.

  As the photo radical initiator, known photo radical initiators can be widely used and are not particularly limited. For example, benzoin ethers such as benzoin ethyl ether, benzoin butyl ether and benzoin isopropyl ether; 4,4′-bis Benzophenones such as dimethylaminobenzophenone and 4,4′-bisdiethylaminobenzophenone; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1- Hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl-]-2-hydroxy-2-methyl-1-propane -1- 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one, 2-methyl-1- [4- (Methylthio) phenyl] -2-morpholino-propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-dimethylamino-2- (4-methylbenzyl) ) -1- (4-morpholin-4-yl-phenyl) -butan-1-one and acetophenones such as N, N-dimethylaminoacetophenone; 2,4-diethylthioxanthone, 2-chlorothioxanthone and 2-isopropyl Thioxanthones such as thioxanthone; Ketals such as benzyl dimethyl ketal and acetophenone dimethyl ketal; 2, 4, -Phosphine oxides such as trimethylbenzoyldiphenylphosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; ethyl-p-dimethylaminobenzoate, (2-dimethylamino) ethylbenzoate, bis- Examples include amine synergists such as 4,4′-dimethylaminobenzophenone.

  Among these, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 And α-aminoacetophenones such as 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one; 2,4,6-trimethylbenzoyl Acylphosphine oxides such as diphenylphosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; and photoradicals having light absorption at long wavelengths (for example, wavelength 300 nm) such as amine synergists Initiators are preferred in terms of deep curability, and acyl phosphine oxides and amine synergists are more preferred.

  Also, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl-]-2-hydroxy-2-methyl Α such as -1-propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one, etc. -Hydroxyacetophenones are preferred because they can improve surface curability.

  Although there is no restriction | limiting in particular in the mixture ratio of a photoradical initiator, 0.01-40 mass parts is preferable with respect to 100 mass parts of (A) component photopolymerizable compounds, and 0.1-30 mass parts is more preferable. . A radical photoinitiator may be used independently and may use 2 or more types together.

  The silanol condensation catalyst is a catalyst for crosslinking and curing the organic polymer having a crosslinkable silicon group as the component (C). Cross-linking cure proceeds by the action of moisture. As the silanol condensation catalyst, a metal alkoxide or a chelate compound thereof can be used. Mention may be made, for example, of alkoxides of metals such as aluminum, titanium, zirconium or cerium, or of the above metals chelated by eg acetoacetic esters or acetylacetone. Among these, an aluminum chelate compound (aluminum complex) is preferable because the pot life required for using the photocurable conductive composition of the present invention can be secured.

  Acids and photoacid generators are also known as silanol condensation catalysts, but since acids corrode metals, they are not particularly suitable for use in electronic circuits and the like. In addition, a tin catalyst often used as a silanol condensation catalyst is too active and it is difficult to obtain a sufficient pot life by screen printing or the like. Therefore, the silanol condensation catalyst is preferably a metal alkoxide such as aluminum, titanium, zirconium or cerium or a chelate compound thereof. Chelate compounds are particularly preferable.

  An aluminum complex is a complex having an Al—O bond, and examples of such a compound include a compound in which an alkoxy group, a phenoxy group, an acyloxy group, an o-carbonylphenolate group, a β-diketonato group, and the like are bonded to an aluminum atom. It is done.

  Here, the alkoxy group is preferably one having 1 to 10 carbon atoms, more specifically, methoxy, ethoxy, isopropoxy, butoxy, pentyloxy, etc., and the phenoxy group includes phenoxy group, o-methylphenoxy. Group, o-methoxyphenoxy group, 2,6-dimethylphenoxy group and the like. Acyloxy groups include ligands such as acetate, propionate, isopropionate, butyrate, stearato, ethylacetoacetate, propylacetoacetate, butylacetoacetate, diethylmalato, dipivaloylmethanato, and the like. Examples of the carbonylphenolate group include salicylaldehyde. Examples of the β-diketonato group include acetylacetonato, trifluoroacetylacetonato, hexafluoroacetylacetonate, and ligands represented by the following formulas (7) to (8).

  Specifically, trismethoxyaluminum, trisethoxyaluminum, trisisopropoxyaluminum, trisphenoxyaluminum, trisparamethylphenoxyaluminum, isopropoxydiethoxyaluminum, trisbutoxyaluminum, tris-2-ethylhexoxyaluminum, trisacetoxyaluminum, Tris stearato aluminum, tris butyrate aluminum, tris propionate aluminum, tris isopropionate aluminum, tris acetyl acetonato aluminum, tris trifluoro acetyl acetonato aluminum, tris hexafluoro acetyl acetonato aluminum, tris ethyl acetoaceto aluminum, tris Salicylaldehyde aluminum, Triszier Lumalolato aluminum, trispropyl acetoacetium aluminum, trisbutyl acetoacetate aluminum, trisdibivaloylmethanato aluminum, cyclohexyloxy diisopropoxyaluminum, diisopropoxy trichloroacetato aluminum, isopropoxy distearate aluminum , Diisopropoxy-acetylacetonatoaluminum, diisopropoxy-ethylacetoacetatoaluminum, diacetylacetonatobivaloylmethanatoaluminum, and compounds represented by the following chemical formula.

  An aluminum complex can be used individually or in mixture of 2 or more types. Of these, trisacetylacetonatoaluminum and trisethylacetoacetonatoaluminum are particularly preferred because of their solubility and their activity is unlikely to decrease when stored for a long time.

  Examples of titanium, zirconium or cerium complexes include tetraisopropyl titanate, tetraisobutyl titanate or triisopropyl acetylacetonyl titanate; tetraisopropyl zirconate or triisopropyl acetylacetonyl zirconate; or cerium triisopropoxy Or cerium acetylacetonate diisopropoxide.

  The blending ratio of the silanol condensation catalyst is not particularly limited, but is preferably 0.01 to 30 parts by weight, and 0.1 to 20 parts by weight with respect to 100 parts by weight of the organic polymer having a silicon-containing group as component (C). Is more preferable. A radical photoinitiator may be used independently and may use 2 or more types together.

  The photocurable conductive composition of the present invention can further contain a resin filler having an average particle diameter of 1 to 150 μm.

The resin filler is a particulate filler made of an organic resin or the like, and known organic fine particles such as polyethyl acrylate, polyurethane, polyethylene, and polypropylene can be used.
For example, as the urea resin-based filler, “PERGOPAK series” manufactured by ALBEMARLE may be used. Examples of the melamine resin filler include “Eposter M30” manufactured by Nippon Shokubai Co., Ltd. Examples of the urethane resin filler include crosslinked urethane resin fillers such as “Art Pearl C-200, C-300, C-400, C-800” manufactured by Negami Kogyo Co., Ltd. Examples of the benzoguanamine resin filler include “Eposter M05, MS” manufactured by Nippon Shokubai Co., Ltd. Examples of the phenol resin filler include “PR-RES-5” manufactured by Sumitomo Bakelite Co., Ltd., “Shonol PMB-1010” manufactured by Showa Polymer Co., Ltd., and the like. As the acrylic resin filler, “Tech Polymer MBX Series” manufactured by Sekisui Plastics Co., Ltd., Art Pearl G-400, G-800, GR-400, GR-800, J-4PY, J manufactured by Negami Kogyo Co., Ltd. -4P, J-4PY, J-5P, J-7P, J7PY, S-5P and the like. Examples of the styrene resin filler include “Techpolymer SBX series” manufactured by Sekisui Plastics Co., Ltd.

  The resin filler (resin fine powder) used in the present invention is preferably a spherical material that can be easily obtained by suspension polymerization of a monomer (for example, methyl methacrylate). Moreover, since the resin filler used by this invention is contained suitably as a filler in a solution composition, Preferably it is a spherical crosslinked resin filler.

  As the resin filler, a urethane resin filler and an acrylic resin filler are preferable, and a urethane resin filler is more preferable in terms of good compatibility with the component (A) and the component (C).

  The average particle size of the resin filler is preferably 1 to 150 μm, more preferably 5 to 30 μm. In the present invention, the average particle diameter is a 50% cumulative particle diameter measured by a laser diffraction scattering method. When the average particle size is smaller than 1 μm, it may be difficult to disperse in the system of the photocurable conductive composition. On the other hand, if it is larger than 150 μm, it tends to be clogged with an application nozzle.

  The Tg of the resin filler is preferably 130 ° C to -60 ° C, more preferably 120 ° C to -50 ° C. Tg is measured by differential scanning calorimetry (DSC method). Although there is no restriction | limiting in particular in the mixture ratio of a resin filler, 0.5-200 mass parts is preferable with respect to 100 mass parts of (A) component, and 1-50 mass parts is more preferable. A resin filler may be used independently and may use 2 or more types together.

  The photocurable conductive composition of the present invention can further contain a moisture absorbent. The moisture absorbent is particularly useful when the present invention contains the component (C). As the moisture absorbent, a silane coupling agent and silicate described later are suitable. The silicate is not particularly limited, and examples thereof include tetraalkoxysilane or a partial hydrolysis condensate thereof. More specifically, tetramethoxysilane, tetraethoxysilane, ethoxytrimethoxysilane, dimethoxydiethoxysilane, methoxy Tetraalkoxysilanes (tetraalkyl silicates) such as triethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, tetra-n-butoxysilane, tetra-i-butoxysilane, tetra-t-butoxysilane, and , And their partial hydrolysis condensates.

  The silane coupling agent used as the moisture absorbent is not particularly limited as long as it acts as a moisture absorbent, but vinyl groups other than (meth) acryloyl groups such as vinyltrimethoxysilane and vinyltriethoxysilane. Preferred are vinyl-type unsaturated group-containing silanes containing alkyl; alkyl silanes such as hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane; and phenyl group-containing silanes.

  Although there is no restriction | limiting in particular in the mixture ratio of a moisture absorber, 0.1-20 mass parts is preferable with respect to 100 mass parts of (B) component, and 0.2-10 mass parts is more preferable. A water | moisture-content absorber may be used independently and may use 2 or more types together.

  The photocurable conductive composition of the present invention can further contain a light-shielding material. The light shielding material imparts light shielding properties to the photocurable conductive composition, and a black pigment is preferable. In order to maintain the workability of the photocurable conductive composition, the light-shielding material preferably imparts light-shielding properties with a small amount of addition. Examples of the light shielding material include inorganic or organic pigments. Examples of the inorganic pigment include carbon powder, ivory black, mars black, peach black, lamp black, inorganic black containing titanium, copper, iron, chromium, manganese, cobalt, and the like. Carbon powder is preferred, carbon black, acetylene black, ketjen black, carbon nanotube, natural graphite powder, artificial graphite powder, etc. are more preferred, and light-curing conductive composition after curing with a small amount of addition Carbon black, acetylene black, and ketjen black are particularly preferable from the viewpoint of imparting. Examples of the organic pigment include aniline black and perylene black, and perylene black is preferable. Examples of commercially available products include black pigments (product name: NBD-0744) manufactured by Nihongo Bix Corporation.

  Although there is no restriction | limiting in particular in the mixture ratio of light-shielding material, 0.001-20 mass parts is preferable with respect to 100 mass parts of (A) component, and 0.01-10 mass parts is more preferable. A light-shielding material may be used independently and may use 2 or more types together.

  Examples of the filler other than the resin filler and the light shielding material include fillers described in paragraph [0158] of JP-A-2005-232419. Of these fillers, crystalline silica, fused silica, dolomite, calcium carbonate, titanium oxide, talc and the like are preferable.

In particular, when it is desired to obtain a cured product having high strength with these fillers, mainly crystalline silica, fused silica, anhydrous silicic acid, hydrous silicic acid, surface-treated fine calcium carbonate, calcined clay, clay, activated zinc white, etc. A filler selected from can be added. Among them, the specific surface area (according to BET adsorption method) of ^{50 m} 2 / g or more, usually 50 to 400 m ² / g, is preferably 100 to 300 m ² / g approximately ultrafine powdery silica preferred. Further, silica whose surface has been previously hydrophobically treated with an organosilicon compound such as organosilane, organosilazane, diorganopolysiloxane, etc. is more preferred.

  Moreover, when it is desired to obtain a cured product having low strength and large elongation, a filler selected mainly from titanium oxide, calcium carbonate, talc, ferric oxide, zinc oxide, shirasu balloon and the like can be added. In general, when calcium carbonate has a small specific surface area, the effect of improving the breaking strength and breaking elongation of the cured product may not be sufficient. The larger the value of the specific surface area, the larger the breaking strength and breaking elongation of the cured product.

  Furthermore, it is more preferable that the calcium carbonate is subjected to a surface treatment using a surface treatment agent. When surface-treated calcium carbonate is used, the storage stability of the photocurable conductive composition of the present invention is further improved as compared to the case where calcium carbonate that has not been surface-treated is used.

  As the surface treatment agent, known ones can be used, and examples include surface treatment agents described in paragraph [0161] of JP-A-2005-232419. It is preferable to process in the range of 0.1-20 mass% with respect to a calcium carbonate, and, as for the processing amount of this surface treating agent, it is more preferable to process in the range of 1-5 mass%. When the treatment amount is less than 0.1% by mass, the workability improvement effect may not be sufficient, and when it exceeds 20% by mass, the storage stability of the photocurable conductive composition may be lowered. . Although there is no particular limitation, when calcium carbonate is used, colloidal calcium carbonate is preferably used when the thixotropy of the blend, the breaking strength of the cured product, and the elongation at break are particularly expected. On the other hand, when heavy calcium carbonate is added for the purpose of increasing the amount of the compound, reducing costs, etc., those described in paragraph [0163] of JP-A-2005-232419 can be used.

  The said filler may be used independently according to the objective and necessity, and may use 2 or more types together. When the filler is used, the addition amount is preferably 5 to 1000 parts by mass and preferably 20 to 500 parts by mass with respect to 100 parts by mass of component (A). It is more preferable to use in the range of 40 to 300 parts by mass. If the blending amount is less than 5 parts by mass, the effect of improving the breaking strength, elongation at break, adhesion and weather resistance of the cured product may not be sufficient, and if it exceeds 1000 parts by mass, the photocurable conductive composition Workability may be reduced.

  Examples of the antioxidant include p-phenylenediamine-based antioxidants, amine-based antioxidants, hindered phenol-based antioxidants, and secondary antioxidants such as phosphorus-based antioxidants and sulfur-based antioxidants. It is done.

  Although the addition amount of antioxidant is not specifically limited, Preferably it is 0.1-10 mass parts with respect to 100 mass parts of (A) component, More preferably, it can be used in 0.5-5 mass parts.

  Although it does not specifically limit as a plasticizer, For example, the plasticizer of Unexamined-Japanese-Patent No. 2005-232419 Paragraph [0173] is mentioned by the objectives, such as adjustment of a physical property and adjustment of a property. Among these, a polyester plasticizer and a vinyl polymer are preferable because the effect of reducing the viscosity is remarkable and the volatilization rate at a high temperature is low. Moreover, the polymer plasticizer which is a polymer having a number average molecular weight of 500 to 15000 adjusts the mechanical properties such as the viscosity of the photocurable conductive composition and the tensile strength and elongation of the cured product of the photocurable conductive composition. This is preferable because the initial physical properties can be maintained over a long period of time compared to the case where a low molecular plasticizer is used. The polymer plasticizer may or may not have a functional group.

  The number average molecular weight of the polymer plasticizer is preferably 500 to 15,000, preferably 800 to 10,000, and more preferably 1000 to 8,000. If the molecular weight is too low, the plasticizer may flow out over time when exposed to heat or in contact with a liquid, and the initial physical properties may not be maintained over a long period of time. Moreover, when molecular weight is too high, a viscosity will become high and there exists a tendency for workability | operativity to fall.

  Of the polymeric plasticizers, those compatible with the vinyl polymer are preferred. Of these, vinyl polymers are preferred from the viewpoints of compatibility, weather resistance, and heat aging resistance. Among the vinyl polymers, (meth) acrylic polymers are preferable, and acrylic polymers are more preferable. Examples of the method for synthesizing the acrylic polymer include those obtained by conventional solution polymerization and solvent-free acrylic polymers. The latter acrylic plasticizer does not use a solvent or a chain transfer agent, and is a high-temperature continuous polymerization method (USP 4414370, JP 59-6207, JP-B-5-58005, JP 1-331522, USP 5010166). It is more preferable because it is manufactured by. Examples include the Toagosei UP series (see the October 1999 issue of industrial materials). Of course, the living radical polymerization method can also be mentioned as another synthesis method. According to this method, the molecular weight distribution of the polymer is narrow and the viscosity can be lowered, and the atom transfer radical polymerization method is more preferable, but it is not limited thereto.

  The molecular weight distribution of the polymer plasticizer is not particularly limited, but is preferably narrow and is preferably less than 1.8. 1.7 or less is more preferable, 1.6 or less is still more preferable, 1.5 or less is more preferable, 1.4 or less is especially preferable, and 1.3 or less is the most preferable.

  The plasticizer containing the above-mentioned polymer plasticizer may be used alone or in combination of two or more, but is not necessarily required. Further, if necessary, a high molecular plasticizer may be used, and a low molecular plasticizer may be further used in a range that does not adversely affect the physical properties. These plasticizers can also be blended at the time of polymer production.

  Although the usage-amount in the case of using a plasticizer is not limited, Preferably it is 1-100 mass parts with respect to 100 mass parts of (A) component, More preferably, it is 5-50 mass parts. If the amount is less than 1 part by mass, the effect as a plasticizer tends to be hardly exhibited, and if it exceeds 100 parts by mass, the mechanical strength of the cured product tends to be insufficient.

  If a low-boiling compound that can be volatilized during curing is used as a reactive diluent, it will change shape before and after curing, or it may adversely affect the environment due to volatiles. An organic compound having a boiling point of 100 ° C. or higher is particularly preferable.

  Specific examples of the reactive diluent include 1-octene, 4-vinylcyclohexene, allyl acetate, 1,1-diacetoxy-2-propene, methyl 1-undecenoate, 8-acetoxy-1,6-octadiene and the like. However, it is not limited to these.

  The addition amount of the reactive diluent is preferably 0.1 to 100 parts by mass, more preferably 0.5 to 70 parts by mass, and further preferably 1 to 50 parts by mass with respect to 100 parts by mass of the component (A). .

  Various types of light stabilizers are known, and are described in, for example, “Antioxidant Handbook” issued by Taiseisha, “Degradation and Stabilization of Polymer Materials” (235-242) issued by CM Chemical Co., Ltd. Although various things are mentioned, it is not necessarily limited to these.

  Among the light stabilizers, ultraviolet absorbers are preferable, and specifically, Tinuvin P, Tinuvin 234, Tinuvin 320, Tinuvin 326, Tinuvin 327, Tinuvin 329, Tinuvin 213 (all of which are manufactured by Ciba Geigy Japan), etc. Examples include benzotriazole compounds, triazine compounds such as Tinuvin 1577, benzophenone compounds such as CHIMASSORB 81, and benzoate compounds such as Tinuvin 120 (manufactured by Ciba Geigy Japan).

  Further, hindered amine compounds are also preferable, and specific examples of such compounds include those described in JP-A-2006-274084, but are not limited thereto. Furthermore, since the combination of the ultraviolet absorber and the hindered amine compound may exhibit more effect, it is not particularly limited, but may be used in combination, and it is preferable to use in combination.

The light stabilizer may be used in combination with the above-described antioxidant, and it is particularly preferable because the effect is further exhibited and the weather resistance may be improved. Tinuvin C353, Tinuvin B75 (all of which are manufactured by Ciba Geigy Japan, Inc.) in which a light stabilizer and an antioxidant are mixed in advance may be used.

  It is preferable that the usage-amount of a light stabilizer is the range of 0.1-10 mass parts with respect to 100 mass parts of (A) component. If it is less than 0.1 parts by mass, the effect of improving the weather resistance is small, and if it exceeds 10 parts by mass, there is no great difference in the effect, which is economically disadvantageous.

  By blending an adhesion-imparting agent, it is possible to improve adhesion to general adherends such as metals, plastics, and glass. As the adhesion-imparting agent, known silane coupling agents are preferable. For example, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, N- (β-aminoethyl)- γ-aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltriethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, 1,3-diaminoisopropyltrimethoxy Amino group-containing silanes such as silane; N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, N- (1,3-dimethylbutylidene) -3- (tri Ketimine type silanes such as methoxysilyl) -1-propanamine; γ-glycidoxypropyltrime Epoxy group-containing silanes such as xysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane; γ-mercaptopropyltrimethoxy Mercapto group-containing silanes such as silane and γ-mercaptopropylmethyldimethoxysilane; (meth) acryloyl group-containing silanes such as γ-methacryloyloxypropyltrimethoxysilane and γ-acryloyloxypropylmethyldimethoxysilane; γ-chloropropyltri Chlorine atom-containing silanes such as methoxysilane; Isocyanate-containing silanes such as γ-isocyanatopropyltriethoxysilane and γ-isocyanatopropylmethyldimethoxysilane; Cycloalkenyl triethoxysilane, diphenyldimethoxysilane, but phenyl group-containing silanes such as diphenyl diethoxy silane, etc., but is not limited thereto. Further, modified amino group-containing silanes modified by reacting the amino group-containing silanes with an epoxy group-containing compound, an isocyanate group-containing compound, and a (meth) acryloyl group-containing compound containing the silanes. It may be used.

  The adhesiveness imparting agent is preferably blended in an amount of 0.01 to 20 parts by mass with respect to 100 parts by mass of the component (A). If it is less than 0.01 part by mass, the effect of improving the adhesiveness is small, and if it exceeds 20 parts by mass, the physical properties of the cured product tend to be lowered. Preferably it is 0.1-10 mass parts, More preferably, it is 0.5-5 mass parts. Only one type of adhesiveness-imparting agent may be used, or two or more types may be used in combination.

  Examples of the solvent include aromatic hydrocarbon solvents such as toluene and xylene; ester solvents such as ethyl acetate, butyl acetate, amyl acetate, and cellosolve; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and diisobutyl ketone. Is mentioned.

  Examples of the photosensitizer include 9,10-dibutoxyanthracene, anthracene, perylene, coronene, tetracene, benzanthracene, phenothiazine, flavin, acridine, ketocoumarin, thioxanthone derivative, benzophenone, acetophenone, 2-chlorothioxanthone, Examples include 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, isopropylthioxanthone, and the like.

  The photocurable conductive composition of the present invention can be prepared as a one-pack type in which all the blending components are blended and sealed in advance, and the A liquid from which only the initiator such as a photoradical initiator is removed and the initiator are filled. It can also be prepared as a two-component type in which the B liquid mixed with a material, a plasticizer, a solvent and the like is mixed immediately before molding.

The photocurable conductive composition of the present invention can be suitably used for the conductive bonding method 1 including the following steps.
(1) A step of placing a second member such as an electronic component such as an IC chip on a part of the first member such as a circuit board. (2) Photocuring at the joint between the first member and the second member. (3) The applied photocurable conductive composition is irradiated with light, photopolymerized and cured, and the electronic components are electrically and mechanically joined by the photocurable conductive composition. Process

  FIG. 1 schematically shows a flow of manufacturing an electrical product by the conductive bonding method 1 using the photocurable conductive composition of the present invention.

  As shown in FIG. 1, a metal wiring 12 is formed on a substrate 10 (FIG. 1A), and an IC chip 16 is placed on the metal wiring 12 (FIG. 1B). The photocurable conductive composition 14 is applied so that the metal wiring 12 and the IC chip 16 are joined (FIG. 1C). Then, the photocurable conductive composition is cured by irradiating the photocurable conductive composition 14 with ultraviolet rays so that the metal wiring 12 and the IC chip 16 (FIG. 1C) are mechanically and electrically joined. And the electric product 18 is completed.

  More specifically, an example in which a copper electrode is formed as the metal wiring 12 on the substrate 10 is shown in FIG. Further, when the IC chip 16 is placed, the photocurable conductive composition 14 is applied, and the resin is cured by irradiation with ultraviolet rays, an electrical product 18 is completed as shown in FIG.

When the photocurable conductive composition of the present invention is a photocurable conductive composition containing the component (C), it can be used for the conductive bonding method 2 including the following steps.
(1) Step of applying a photocurable conductive composition to a part of a first member such as a circuit board (2) Irradiating the applied photocurable conductive composition with light, First curing step (3) for photopolymerizing and curing the acrylic compound to impart adhesiveness to the photocurable conductive composition (3) Second member such as an IC chip on the photocurable conductive composition application portion of the first member (4) The second curing step in which the first member and the second member are bonded and cured by moisture curing of the organic polymer having a crosslinkable silicon group as the component (C) after the bonding. In order to impart adhesiveness to the photocurable conductive composition in the first curing step, the second member is temporarily fixed without using a fixing jig or the like when the second member such as an IC chip is joined. it can.

  FIG. 2 schematically shows a flow of manufacturing an electrical product by the conductive bonding method 2 using the photocurable conductive composition of the present invention.

  As shown in FIG. 2, a metal wiring 12 is formed on a substrate 10 (FIG. 2A), and a photocurable conductive composition 14 is applied on the metal wiring 12 (FIG. 2B). Application | coating can be performed by screen printing, for example. Then, the photocurable conductive composition 14 is exposed to ultraviolet rays to develop adhesiveness (FIG. 2 (c)), and the IC chip 16 is formed using the photocurable conductive composition 14 exhibiting the adhesiveness. Is pasted (FIG. 2D). Then, the electrical product 18 is completed by being cured by moisture in the air.

  An example in which a copper electrode is formed as the metal wiring 12 on the substrate 10 is shown in FIG. Moreover, when the photocurable conductive composition 14 is applied, ultraviolet light is irradiated to develop adhesiveness, and the IC chip 16 is attached and cured, an electrical product 18 is completed as shown in FIG.

In irradiating the electromagnetic wave, the electromagnetic wave is preferably light having a wavelength range of 200 to 450 nm, and more preferably light having a wavelength range of 250 to 430 nm. The light source is not particularly limited, and for example, a high pressure mercury lamp, an ultra high pressure mercury lamp, a carbon arc lamp, a mercury vapor arc, a fluorescent lamp, an argon glow lamp, a halogen lamp, an incandescent lamp, a low pressure mercury lamp, a flash UV lamp, deep UV A lamp, a xenon lamp, a tungsten filament lamp, an LED lamp, sunlight, etc. are mentioned. With these light sources, integrated light quantity 500 mJ / cm ² or more, preferably by irradiation with light so that the 1500 mJ / cm ² or more, it is possible to cure the photo-curable electroconductive composition of the present invention.

  Examples of electromagnetic waves include rays of far ultraviolet rays, ultraviolet rays, near ultraviolet rays, infrared rays and the like, electromagnetic rays such as X-rays and γ rays, electron beams, proton beams, and neutron rays. In view of the curing speed, the availability of the irradiation device, the price, etc., curing by ultraviolet irradiation is preferable.

  The photocurable conductive composition of the present invention can also be suitably used as a conductive adhesive that can replace solder. It can also be used to form a conductive circuit of a printed board by screen printing or a photo resist method. When the photocurable conductive composition of the present invention is used, an electrical product that does not use solder can be manufactured at low cost.

  The present invention will be described more specifically with reference to the following examples. However, it is needless to say that these examples are shown by way of illustration and should not be construed in a limited manner.

Synthesis Example 1 Synthesis of Bifunctional Acrylic Oligomer Polymer A1 having an acryloyl group was synthesized using an atom transfer radical method. 100 parts of n-butyl acrylate were deoxygenated. The inside of the reaction vessel was deoxygenated, 0.42 parts of cuprous bromide, 20 parts of deoxygenated n-butyl acrylate, 4.4 parts of acetonitrile, diethyl 2,5-dipromodidipate 1.8 Part was added and mixed at 80 ° C., and 0.018 part of pentamethyldiethylenetriamine (hereinafter abbreviated as triamine) was added to initiate the polymerization reaction. The remaining 80 parts of n-butyl acrylate was sequentially added to proceed the polymerization reaction. During the polymerization, triamine was appropriately added to adjust the polymerization rate, and the polymerization was allowed to proceed while adjusting the internal temperature to about 80 ° C to about 90 ° C. When the monomer conversion rate (polymerization reaction rate) was about 95% or more, oxygen-nitrogen mixed gas was introduced into the gas phase of the reaction vessel, and the mixture was heated and stirred while maintaining the internal temperature at about 80 ° C to about 90 ° C. Volatiles were removed under reduced pressure and concentrated. This was diluted with butyl acetate, filtered and added with a filter aid. Adsorbents (KYOWARD 700SEN, KYOWARD 500SH manufactured by Kyowa Chemical Industry Co., Ltd.) were added to the filtrate, heated and stirred, and then filtered to concentrate the filtrate. This is dissolved in N, N-dimethylacetamide, potassium acrylate (about 2 molar equivalents relative to the terminal Br group), heat stabilizer (H-TEMPO: 4-hydroxy-2,2,6,6-tetramethyl). Piperidine-n-oxyl) and an adsorbent (KYOWARD 700SEN) were added, and the mixture was heated and stirred at about 70 ° C. Volatile components were distilled off under reduced pressure, diluted with butyl acetate, filtered and added with a filter aid. The filtrate was concentrated to obtain a polymer A1 having acryloyl groups as ultraviolet crosslinking groups at both ends. The number average molecular weight of the polymer A1 was 22500, the molecular weight distribution was 1.25, and the average number of acryloyl groups introduced per polymer molecule was 1.9.

(Synthesis Example 2) Synthesis of acrylate-based polymer having a crosslinkable silicon group In a nitrogen atmosphere, CuBr (1.09 kg), acetonitrile (11.4 kg), butyl acrylate (26.0 kg) and 250 L reactor were used. Diethyl 2,5-dibromoadipate (2.28 kg) was added and stirred at 70-80 ° C. for about 30 minutes. To this was added pentamethyldiethylenetriamine to initiate the reaction. 30 minutes after the start of the reaction, butyl acrylate (104 kg) was continuously added over 2 hours. During the reaction, pentamethyldiethylenetriamine was appropriately added so that the internal temperature became 70 ° C to 90 ° C. The total amount of pentamethyldiethylenetriamine used so far was 220 g. Four hours after the start of the reaction, volatile components were removed by heating and stirring at 80 ° C. under reduced pressure. Acetonitrile (45.7 kg), 1,7-octadiene (14.0 kg) and pentamethyldiethylenetriamine (439 g) were added thereto, and stirring was continued for 8 hours. The mixture was heated and stirred at 80 ° C. under reduced pressure to remove volatile components. Toluene is added to this concentrate to dissolve the polymer, diatomaceous earth is added as a filter aid, aluminum silicate and hydrotalcite are added as adsorbents, and an oxygen-nitrogen mixed gas atmosphere (oxygen concentration 6%) is set to an internal temperature of 100. The mixture was heated and stirred at ° C. The solid content in the mixed solution was removed by filtration, and the filtrate was heated and stirred at an internal temperature of 100 ° C. under reduced pressure to remove volatile components.

  Furthermore, aluminum silicate, hydrotalcite, and a heat deterioration inhibitor were added as adsorbents to this concentrate, and the mixture was heated and stirred under reduced pressure (average temperature of about 175 ° C., reduced pressure of 10 Torr or less). Further, aluminum silicate and hydrotalcite were added as adsorbents, an antioxidant was added, and the mixture was heated and stirred at an internal temperature of 150 ° C. in an oxygen-nitrogen mixed gas atmosphere (oxygen concentration 6%). Toluene was added to this concentrate to dissolve the polymer, and then the solid content in the mixed solution was removed by filtration. The filtrate was heated and stirred under reduced pressure to remove volatile matter, and the polymer having an alkenyl group was removed. Obtained. Polymer having this alkenyl group, dimethoxymethylsilane (2.0 molar equivalents relative to alkenyl group), methyl orthoformate (1.0 molar equivalents relative to alkenyl group), platinum catalyst [bis (1,3-divinyl (-1,1,3,3-tetramethyldisiloxane) Platinum complex catalyst xylene solution 10 mg of 1 kg of polymer was mixed, and the mixture was heated and stirred at 100 ° C. in a nitrogen atmosphere. After confirming disappearance of the alkenyl group, the reaction mixture was concentrated to obtain a poly (acrylic acid-n-butyl) polymer C1 having a dimethoxysilyl group at the terminal. The number average molecular weight of the obtained polymer C1 was about 26000, Mw / Mn was 1.3, and Tg was −56.0 ° C. When the average number of silyl groups introduced per molecule of the polymer was determined by 1H NMR analysis, it was about 1.8.

(Synthesis Example 3) Synthesis of Acrylic Ester Polymer Having Crosslinkable Silicon Group 40 parts by mass of ethyl acetate as a solvent, 59 parts by mass of methyl methacrylate, 25 parts by mass of 2-ethylhexyl methacrylate, γ-methacryloxypropylmethyl 21 parts by mass of dimethoxysilane and 0.1 parts by mass of ruthenocene dichloride as a metal catalyst were charged and heated to 80 ° C. while introducing nitrogen gas. Next, 7.5 parts by mass of 3-mercaptopropylmethyldimethoxysilane was added to the flask and reacted at 80 ° C. for 6 hours. After cooling to room temperature, 20 parts by mass of a benzoquinone solution (95% THF solution) was added to terminate the polymerization. Acrylic ester polymer having a dimethoxysilyl group having a polystyrene-reduced mass average molecular weight of about 6000, Mw / Mn of 1.6, and Tg of about 60 ° C. C2 was obtained.

Example 1
In a mixture ratio (weight basis) shown in Table 1, in a flask equipped with a stirrer and a thermometer, lauryl acrylate, isostearyl acrylate, phenoxy-polyethylene glycol acrylate, polymer A1 obtained in Synthesis Example 1, Synthesis Example 2 Polymer C1 obtained in Example 1, Polymer C2 obtained in Synthesis Example 3, dendritic silver-coated copper and scaly silver-coated copper (1400YP (10%): 1400YP (copper powder) manufactured by Mitsui Mining & Smelting Co., Ltd.) Silver plated copper powder silver-plated at a weight ratio of 10%, 50% particle diameter (D50) 5.81 μm, standard deviation (SD) 2.74 μm, 10% particle diameter (D10) 3.58 μm, 90% particle diameter ( D90) 9.03 μm, SD / D50 value 0.47, D90 / D10 value 2.52). The mixture was kneaded and dehydrated by heating (100 ° C.), degassing and stirring for 2 hours.

  After cooling, 1,6-hexanediol diacrylate, 3-acryloxypropyltrimethoxysilane, and a photopolymerizable dendrimer compound were added to the mixture, followed by mixing and stirring.

  Further, Darocur 1173 (manufactured by BASF Japan, 2-hydroxy-2-methyl-1-phenyl-propan-1-one), Irgacure 651 (manufactured by BASF Japan, 2,2-dimethoxy-1,2-diphenyl) are used as photoinitiators. Ethane-1-one), Irgacure 819 (manufactured by BASF Japan, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide) as a silanol condensation catalyst, aluminum chelate D (manufactured by Kawaken Fine Chemical Co., Ltd.), aluminum A photocurable conductive composition was prepared by adding a mixture of monoacetylacetonate bis (ethylacetoacetate)) and mixing and stirring.

  The obtained photocurable conductive composition was evaluated for tack immediately after UV irradiation, lateral pressing shear adhesive strength of the chip, and volume resistivity. The test results are shown in Table 1. In Example 1, the integrated light amount was adjusted to such an extent that tack was developed after UV irradiation. However, when the integrated light amount was further increased, tack was reduced and the photocurable conductive composition was further cured. Further, by increasing the amount of the photopolymerizable compound (A) or using a photopolymerizable compound having high reactivity, the photocurable conductive composition is sufficiently cured to the extent that there is no tack. Can be made.

(Comparative Example 1)
Instead of the flaky silver-coated copper (1400 YP (10%)) of Example 1, the flaky silver-coated copper (Silcoat AgB: manufactured by Fukuda Metal Co., Ltd.), silver powder, 50% particle size 4.19 μm, standard deviation (SD) Example 1 except that 4.31 μm, 10% particle size (D10) 1.50 μm, 90% particle size (D90) 9.94 μm, SD / D50 value 1.03, D90 / D10 value 6.63) were used. In the same manner as above, a photocurable conductive composition was prepared, and the tack immediately after UV irradiation, the lateral pressing shear adhesive strength of the chip, and the volume resistivity were evaluated. The evaluation results are shown in Table 1.

  The evaluation method of tack immediately after UV irradiation, lateral pressing shear adhesive strength of the chip and volume resistivity is as follows.

1) Tack (initial adhesion) test immediately after UV irradiation A photocurable conductive composition was applied to a thickness of about 100 μm on a PET film (100 mm × 100 mm × 0.1 mm), and UV irradiation (irradiation conditions: metal halide lamp ( intensity 770mW / ^cm 2), integrated light quantity: 3000 mJ / cm ^2), and a sample of tackiness (tack) was evaluated by the following evaluation criteria by finger touch.
○: Adhesive, △: Adhesive somewhat (between adhesive and liquid), ×: Liquid

2) Test of lateral pressing shear adhesive strength of chip First, as shown in FIG. 3, a printed circuit board (FR4) having a copper electrode 12 formed thereon was prepared. Then, in the same manner as the flow shown in FIG. 2, screen (stencil) printing is performed on the copper electrode of the printed circuit board (FR4) using a 100 μm-thick mask as a photocurable conductive composition as an adhesive, and UV. irradiation (irradiation conditions: a metal halide lamp (illuminance 770mW / ^cm 2), integrated light quantity: 3000 mJ / cm ²⁾ and then, crimped tin plated chip (2012 size), a test piece as shown in FIG. 2 (d) Produced. Then, after curing at 23 ° C. and 50% RH for 24 hours, or curing at 80 ° C. for 1 hour and 23 ° C. and 50% RH for 12 hours, the chip was subjected to a transverse shear test. The lateral push shear test of the chip was performed using a pull push meter at a test speed of 30 mm / sec.

3) Measurement of volume resistivity A photocurable conductive composition is applied to a PET film (100 mm × 100 mm × 0.1 mm) to a thickness of about 100 μm, and UV irradiation (irradiation conditions: metal halide lamp (illuminance 770 mW / cm ² )) , Integrated light quantity: 3000 mJ / cm ² ) to produce a cured product sheet. The volume resistivity was measured by a four-end needle method using Lorester MCP-T360 manufactured by Mitsubishi Chemical Corporation. The volume resistivity is not less than 1 × 10 ⁷ Ω · cm, which is the upper limit value determined at the time of measurement. D. It was.

* 1 Light acrylate P-200A, manufactured by Kyoeisha Chemical Co., Ltd. * 2 KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd. * 3 Biscoat # 1000: manufactured by Osaka Organic Chemical Industry Co., Ltd. * 4 ACAX-3: manufactured by Mitsui Kinzoku Mining Co., Ltd. Silver-plated copper powder silver-plated on dendritic (dendritic) copper powder at a weight ratio of 20%, 50% average particle diameter (D50) 16.4 μm, specific surface area 0.41 m ² / g, tap density 1.05 g / cm ³ .
* 5 1400YP (10%): manufactured by Mitsui Mining & Smelting Co., Ltd. 1400YP (copper powder), silver-plated copper powder silver-plated at a weight ratio of 10%, 50% particle diameter (D50) 5.81 μm, standard deviation (SD ) 2.74 μm, 10% particle size (D10) 3.58 μm, 90% particle size (D90) 9.03 μm, SD / D50 value 0.47, D90 / D10 value 2.52.
* 6 Silcote AgB: Fukuda Metal Co., Ltd., silver powder, 50% particle size 4.19 μm, standard deviation (SD) 4.31 μm, 10% particle size (D10) 1.50 μm, 90% particle size (D90) 9 .94 μm, SD / D50 value 1.03, D90 / D10 value 6.63.
* 7 Darocur 1173 (BASF Japan, 2-hydroxy-2-methyl-1-phenyl-propan-1-one),
* 8 Irgacure 651 (manufactured by BASF Japan, 2,2-dimethoxy-1,2-diphenylethane-1-one),
* 9 Irgacure 819 (manufactured by BASF Japan, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide)
* 10 Aluminum chelate D: Trade name, aluminum monoacetylacetonate bis (ethyl acetoacetate), manufactured by Kawaken Fine Chemical Co., Ltd.

10: substrate, 12: metal wiring, 14: photocurable conductive composition of the present invention, 16: IC chip, 18: electrical product.

Claims (5)

(A) a photopolymerizable compound having a group represented by formula (1),
-OC (O) C (R) = CH ₂ (1)
(In the formula (1), R represents a hydrogen atom or a methyl group), and (B) a photocurable conductive composition containing a conductive powder,
(I) The conductive powder of component (B) is silver or silver-coated powder,
(Ii) The conductive powder of component (B) is (B-1) dendritic conductive powder, and (B-2) 10% particle size by laser diffraction scattering type particle size distribution measurement method is D10, and 50% particle size is D50. When the 90% particle size is D90 and the standard deviation of the particle size is SD, SD / D50 is 0.5 or less and D90 / D10 is a mixture of flaky conductive powders of 4.0 or less. ,
(Iii) The content of the conductive powder of the component (B) is 100 to 600 parts by mass with respect to 100 parts by mass of the photocurable conductive composition excluding the solvent and the conductive powder of the component (B).
A photocurable conductive composition characterized by the above.   The photocurable type according to claim 1, further comprising (C) an organic polymer having a hydrolyzable group bonded to a silicon atom and having a silicon-containing group capable of crosslinking by forming a siloxane bond. Conductive composition.   (C) An organic polymer having a hydrolyzable group bonded to a silicon atom and having a silicon-containing group that can be crosslinked by forming a siloxane bond is a crosslinkable silyl group-containing polyoxyalkylene polymer and a crosslinkable polymer. The photocurable conductive composition according to claim 2, which is at least one compound selected from the group consisting of a silyl group-containing (meth) acrylic polymer.   It uses for adhesion | attachment of an electronic component, The photocurable conductive composition of any one of Claims 1-3 characterized by the above-mentioned.   An electrical product using the photocurable conductive composition according to claim 4.

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